U.S. patent application number 13/632289 was filed with the patent office on 2013-01-31 for polycarbonate resin composition, method for producing same and molded article of this resin composition.
The applicant listed for this patent is Tatsuya HITOMI, Michio NAKATA, Ryouhei NISHIHARA, Tetsurou NOBUYASU, Kazuyuki TAKAHASHI, Kenji TSURUHARA, Ryuuji UCHIMURA, Masanori YAMAMOTO, Tomonari YOKOYAMA. Invention is credited to Tatsuya HITOMI, Michio NAKATA, Ryouhei NISHIHARA, Tetsurou NOBUYASU, Kazuyuki TAKAHASHI, Kenji TSURUHARA, Ryuuji UCHIMURA, Masanori YAMAMOTO, Tomonari YOKOYAMA.
Application Number | 20130030112 13/632289 |
Document ID | / |
Family ID | 44762841 |
Filed Date | 2013-01-31 |
United States Patent
Application |
20130030112 |
Kind Code |
A1 |
HITOMI; Tatsuya ; et
al. |
January 31, 2013 |
POLYCARBONATE RESIN COMPOSITION, METHOD FOR PRODUCING SAME AND
MOLDED ARTICLE OF THIS RESIN COMPOSITION
Abstract
To provide a polycarbonate resin composition excellent in the
surface hardness, the heat resistance, the moldability and the
flame retardancy. A polycarbonate resin composition comprising at
least a polycarbonate resin (a) and a polycarbonate resin (b)
having structural units different from the polycarbonate resin (a),
which satisfies the following requirements: (i) the pencil hardness
of the polycarbonate resin (a) as specified by ISO 15184 is higher
than the pencil hardness of the polycarbonate resin (b) as
specified by ISO 15184; (ii) the glass transition point Tg(a) of
the polycarbonate resin (a) and the glass transition point Tg(b) of
the polycarbonate resin (b) satisfy the relation of the following
(Formula 1): Tg(b)-45.degree. C.<Tg(a)<Tg(b)-10.degree. C.
(Formula 1) and (iii) the pencil hardness of the polycarbonate
resin composition as specified by ISO 15184 is higher by at least
two ranks than the pencil hardness of the polycarbonate resin (b)
as specified by ISO 15184.
Inventors: |
HITOMI; Tatsuya;
(Kitakyushu-shi, JP) ; NISHIHARA; Ryouhei;
(Kitakyushu-shi, JP) ; YAMAMOTO; Masanori;
(Kitakyushu-shi, JP) ; NAKATA; Michio;
(Kitakyushu-shi, JP) ; NOBUYASU; Tetsurou;
(Kitakyushu-shi, JP) ; UCHIMURA; Ryuuji;
(Kitakyushu-shi, JP) ; TAKAHASHI; Kazuyuki;
(Kitakyushu-shi, JP) ; TSURUHARA; Kenji;
(Kitakyushu-shi, JP) ; YOKOYAMA; Tomonari;
(Hiratsuka-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
HITOMI; Tatsuya
NISHIHARA; Ryouhei
YAMAMOTO; Masanori
NAKATA; Michio
NOBUYASU; Tetsurou
UCHIMURA; Ryuuji
TAKAHASHI; Kazuyuki
TSURUHARA; Kenji
YOKOYAMA; Tomonari |
Kitakyushu-shi
Kitakyushu-shi
Kitakyushu-shi
Kitakyushu-shi
Kitakyushu-shi
Kitakyushu-shi
Kitakyushu-shi
Kitakyushu-shi
Hiratsuka-shi |
|
JP
JP
JP
JP
JP
JP
JP
JP
JP |
|
|
Family ID: |
44762841 |
Appl. No.: |
13/632289 |
Filed: |
October 1, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
PCT/JP2011/058336 |
Mar 31, 2011 |
|
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13632289 |
|
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Current U.S.
Class: |
524/537 ;
264/176.1; 264/328.1; 525/462 |
Current CPC
Class: |
C08L 2205/02 20130101;
B29K 2105/0094 20130101; B29B 9/06 20130101; B29K 2995/0046
20130101; B29C 48/022 20190201; B29K 2995/002 20130101; B29B 9/12
20130101; B32B 5/145 20130101; C08L 69/00 20130101; B29K 2995/0089
20130101; B32B 27/365 20130101; B29L 2007/002 20130101; C08K 3/016
20180101; B29L 2007/008 20130101; C08L 69/00 20130101; B29K
2105/0067 20130101; B29K 2995/0088 20130101; B29K 2995/007
20130101; C08L 69/00 20130101; B29C 48/08 20190201; B29C 45/0001
20130101; C08L 69/00 20130101; C08L 2666/18 20130101; C08L 2205/02
20130101; B29B 7/46 20130101; B29K 2069/00 20130101 |
Class at
Publication: |
524/537 ;
264/328.1; 264/176.1; 525/462 |
International
Class: |
C08L 69/00 20060101
C08L069/00; B29C 47/00 20060101 B29C047/00; B29C 45/00 20060101
B29C045/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 31, 2010 |
JP |
2010-083181 |
Nov 25, 2010 |
JP |
2010-262055 |
Nov 25, 2010 |
JP |
2010-262056 |
Jan 31, 2011 |
JP |
2011-018525 |
Jan 31, 2011 |
JP |
2011-018526 |
Mar 4, 2011 |
JP |
2011-047877 |
Mar 30, 2011 |
JP |
2011-076450 |
Claims
1. A polycarbonate resin composition comprising at least a
polycarbonate resin (a) and a polycarbonate resin (b) having
structural units different from the polycarbonate resin (a), which
satisfies the following requirements: (i) the pencil hardness of
the polycarbonate resin (a) as specified by ISO 15184 is higher
than the pencil hardness of the polycarbonate resin (b) as
specified by ISO 15184; (ii) the glass transition point Tg(a) of
the polycarbonate resin (a) and the glass transition point Tg(b) of
the polycarbonate resin (b) satisfy the relation of the following
(Formula 1): Tg(b)-45.degree. C.<(a)<Tg(b)-10.degree. C.
(Formula 1) and (iii) the pencil hardness of the polycarbonate
resin composition as specified by ISO 15184 is higher by at least
two ranks than the pencil hardness of the polycarbonate resin (b)
as specified by ISO 15184.
2. A polycarbonate resin composition comprising at least a
polycarbonate resin (a) and a polycarbonate resin (b) having
structural units different from the polycarbonate resin (a), which
satisfies the following requirements: (i) the pencil hardness of
the polycarbonate resin (a) as specified by ISO 15184 is higher
than the pencil hardness of the polycarbonate resin (b) as
specified by ISO 15184; and (ii) the ratio of the intrinsic
viscosity [.eta.](a) of the polycarbonate resin (a) to the
intrinsic viscosity [.eta.](b) of the polycarbonate resin (b),
[.eta.](a)/[.eta.](b), is at least 0.1 and at most 0.65.
3. The polycarbonate resin composition according to claim 1,
wherein the ratio of the viscosity average molecular weight Mv(a)
of the polycarbonate resin (a) to the viscosity average molecular
weight Mv(b) of the polycarbonate resin (b), Mv(a)/Mv(b), is at
least 0.1 and at most 2.0.
4. The polycarbonate resin composition according to claim 1,
wherein the weight ratio of the polycarbonate resin (a) to the
polycarbonate resin (b) in the polycarbonate resin composition is
within a range of from 1:99 to 45:55.
5. The polycarbonate resin composition according to claim 1,
wherein the pencil hardness of the polycarbonate resin (a) as
specified by ISO 15184 is at least F.
6. The polycarbonate resin composition according to claim 1,
wherein the pencil hardness of the polycarbonate resin composition
as specified by ISO 15184 is at least HB.
7. The polycarbonate resin composition according to claim 1,
wherein the above Tg(a) and Tg(b) satisfy the relation of the
following (Formula 2): Tg(b)-30.degree.
C.<Tg(a)<Tg(b)-15.degree. C. (Formula 2)
8. The polycarbonate resin composition according to claim 1,
wherein the polycarbonate resin (a) is a polycarbonate resin having
at least structural units derived from a compound represented by
the following formula (1): ##STR00018## wherein each of R.sup.1 and
R.sup.2 which are independent of each other, is a substituted or
non-substituted C.sub.1-20 alkyl group or a substituted or
non-substituted aryl group, each of R.sup.3 and R.sup.4 which are
independent of each other, is a hydrogen atom, a substituted or
non-substituted C.sub.1-20 alkyl group or a substituted or
non-substituted aryl group, and X is a single bond, a carbonyl
group, a substituted or non-substituted alkylidene group, an
oxidized or non-oxidized sulfur atom, or an oxygen atom.
9. The polycarbonate resin composition according to claim 1,
wherein the polycarbonate resin (a) is a polycarbonate resin having
at least structural units derived from at least one compound
selected from the group consisting of the following formulae (1a)
to (1c): ##STR00019##
10. The polycarbonate resin composition according to claim 1,
wherein the polycarbonate resin (b) is a polycarbonate resin having
mainly structural units derived from a compound represented by the
following formula (2): ##STR00020##
11. The polycarbonate resin composition according to claim 1, which
has a yellowness index (YI) of at most 4.0.
12. The polycarbonate resin composition according to claim 1, which
further contains a flame retardant.
13. A method for producing the polycarbonate resin composition as
defined in claim 1, which comprises melt-kneading the polycarbonate
resin (a) and the polycarbonate resin (b).
14. A method for producing the polycarbonate resin composition as
defined in claim 1, which comprises dry-blending the polycarbonate
resin (a) and the polycarbonate resin (b).
15. An injection-molded article, which is obtained by
injection-molding the polycarbonate resin composition as defined in
claim 1.
16. An extruded article, which is obtained by extruding the
polycarbonate resin composition as defined in claim 1.
17. The extruded article according to claim 16, which is a sheet or
a film.
18. A molded article of polycarbonate resin, comprising the
polycarbonate resin composition as defined in claim 8, wherein the
ratio of the content [S] of the structural units (a) derived from a
compound represented by the following formula (1) on the surface of
the molded article of polycarbonate resin to the content [T] in the
entire molded article of polycarbonate resin ([S]/[T]) is higher
than 1.00 and at most 2.00: ##STR00021## wherein each of R.sup.1
and R.sup.2 which are independent of each other, is a substituted
or non-substituted C.sub.1-20 alkyl group or a substituted or
non-substituted aryl group, each of R.sup.3 and R.sup.4 which are
independent of each other, is a hydrogen atom, a substituted or
non-substituted C.sub.1-20 alkyl group or a substituted or
non-substituted aryl group, and X is a single bond, a carbonyl
group, a substituted or non-substituted alkylidene group, an
oxidized or non-oxidized sulfur atom, or an oxygen atom.
19. The molded article of polycarbonate resin according to claim
18, which is an injection-molded article.
20. The molded article of polycarbonate resin according to claim
18, wherein the ratio of the content [S] of the structural units
(a) on the surface of the molded article of polycarbonate resin to
the content [T] in the entire molded article of polycarbonate resin
([S]/[T]) is at least 1.01 and at most 1.50.
21. The molded article of polycarbonate resin according to claim
18, wherein the pencil hardness on the surface of the molded
article of polycarbonate resin as specified by ISO 15184 is at
least HB.
22. The molded article of polycarbonate resin according to claim
18, wherein the structural units (a) are structural units derived
from at least one compound selected from the group consisting of
the following formulae (1a) to (1c): ##STR00022##
23. The molded article of polycarbonate resin according to claim
18, wherein the polycarbonate resin (b) is a polycarbonate resin
having mainly structural units (b) derived from a compound
represented by the following formula (2): ##STR00023##
24. The molded article of polycarbonate resin according to claim
18, which comprises at least a polycarbonate resin (a) having
structural units (a) derived from a compound represented by the
formula (1) and a polycarbonate resin (b) having structural units
(b) different from the structural units (a) and having a structure
different from the polycarbonate resin (a).
25. The molded article of polycarbonate resin according to claim
18, wherein the pencil hardness of the polycarbonate resin (a) as
specified by ISO 15184 is higher than the pencil hardness of the
polycarbonate resin (b) as specified by ISO 15184.
26. The molded article of polycarbonate resin according to claim
18, wherein the pencil hardness of the polycarbonate resin (a) as
specified by ISO 15184 is at least F.
27. The molded article of polycarbonate resin according to claim
18, wherein the viscosity average molecular weight of the
polycarbonate resin (a) is higher than the viscosity average
molecular weight of the polycarbonate resin (b).
28. A method for producing the molded article of polycarbonate
resin as defined in claim 18, comprising at least a polycarbonate
resin (a) having structural units (a) derived from a compound
represented by the following formula (1) and a polycarbonate resin
(b) having structural units (b) different from the structural units
(a), which comprises melt-kneading or dry-blending the
polycarbonate resin (a) and the polycarbonate resin (b), followed
by molding, wherein the viscosity average molecular weight of the
polycarbonate resin (a) is higher than the viscosity average
molecular weight of the polycarbonate resin (b): ##STR00024##
wherein each of R.sup.1 and R.sup.2 which are independent of each
other, is a substituted or non-substituted C.sub.1-20 alkyl group
or a substituted or non-substituted aryl group, each of R.sup.3 and
R.sup.4 which are independent of each other, is a hydrogen atom, a
substituted or non-substituted C.sub.1-20 alkyl group or a
substituted or non-substituted aryl group, and X is a single bond,
a carbonyl group, a substituted or non-substituted alkylidene
group, an oxidized or non-oxidized sulfur atom, or an oxygen
atom.
29. The method for producing the molded article of polycarbonate
resin according to claim 28, wherein the structural units (a) are
structural units derived from at least one compound selected from
the group consisting of the following formulae (1a) to (1c):
##STR00025##
30. The method for producing the molded article of polycarbonate
resin according to claim 28, wherein the structural units (b) are
mainly structural units derived from a compound of the following
formula (2): ##STR00026##
31. The method for producing the molded article of polycarbonate
resin according to claim 28, wherein the molding is
injection-molding.
Description
TECHNICAL FIELD
[0001] The present invention relates to a polycarbonate resin
composition and a method for producing it, and a molded article of
the resin composition. More particularly, it relates to a
polycarbonate resin composition comprising at least two types of
polycarbonate resins differing in structural units, and a method
for producing it.
BACKGROUND ART
[0002] A polycarbonate resin is excellent in the mechanical
strength, the electrical properties, the transparency and the like,
and is widely used as an engineering plastic in various fields such
as electric and electronic equipment fields and automobile fields.
In recent years, in such application fields, reduction in
thickness, downsizing and weight saving of molded articles are in
progress, and further improvement in the performance of materials
to be molded is required. However, a conventional polycarbonate
resin made of bisphenol A as a raw material has not necessarily
been sufficiently excellent in the surface hardness. Accordingly,
development of a polycarbonate resin having a high surface hardness
has been desired, and several proposals have been made.
[0003] For example, Patent Documents 1 and 2 propose a method for
producing a polycarbonate or a copolycarbonate excellent in the
surface hardness by using a bisphenol different from bisphenol A as
a monomer. However, by this method, even though a polycarbonate
resin composition excellent in the surface hardness is obtained, it
is necessary to sacrifice other physical properties.
[0004] Further, Patent Document 3 proposes a method of bonding
different types of polymers on a molded specimen such as hard
coating treatment, to form a multilayered structure. However, this
method has such a problem that the shape of the molded article is
limited to a sheet shape or the like, and the application is
limited. Further, it has drawbacks of low productivity such that
the number of steps increases so as to achieve a multilayered
structure, a complicated treatment is required at the time of
molding, and defective articles are molded at the time of hard
coating.
[0005] Further, Patent Document 4 proposes to improve the surface
hardness of a blended material of a polycarbonate resin derived
from dimethyl bisphenol cyclohexane and a bisphenol A type
polycarbonate resin.
PRIOR ART DOCUMENTS
Patent Documents
[0006] Patent Document 1: JP-A-64-69625 [0007] Patent Document 2:
JP-A-8-183852 [0008] Patent Document 3: JP-A-2010-188719 [0009]
Patent Document 4: WO2009/083933
DISCLOSURE OF INVENTION
Technical Problem
[0010] With materials obtained by conventional methods, a
polycarbonate resin composition which has high strength even though
it is thin, which has excellent heat resistance, moldability, flame
retardancy and the like, which has a high surface hardness and
which is excellent in the color, could not be obtained.
[0011] Under these circumstances, the object of the present
invention is to provide a polycarbonate resin composition being
particularly excellent in the surface hardness and having excellent
heat resistance, moldability (fluidity), color, impact resistance
and flame retardancy.
Solution to Problem
[0012] The present inventors have conducted extensive studies to
achieve the above objects and as a result, they have found that a
polycarbonate resin composition which attains the above objects can
be achieved by a polycarbonate resin composition containing
specific two types of polycarbonate resins, and accomplished the
present invention. Specifically, it was found that a polycarbonate
resin composition having an excellent surface hardness and having
excellent heat resistance, moldability, color and impact
resistance, can be obtained by a polycarbonate resin composition
comprising a polycarbonate resin (b) and a polycarbonate resin (a)
having a pencil hardness higher than the polycarbonate resin (b)
and having a specific glass transition temperature (Tg(a)).
[0013] More specifically, it was found that by mixing a resin
having Tg in a specific range, physical properties, particularly
the surface hardness of a polycarbonate resin composition are
specifically improved. Further, it was found that a polycarbonate
resin composition of the present invention having a flame retardant
incorporated in the polycarbonate resin has favorable flame
retardancy.
[0014] That is, the present invention provides the following.
<1> A polycarbonate resin composition comprising at least a
polycarbonate resin (a) and a polycarbonate resin (b) having
structural units different from the polycarbonate resin (a), which
satisfies the following requirements:
[0015] (i) the pencil hardness of the polycarbonate resin (a) as
specified by ISO 15184 is higher than the pencil hardness of the
polycarbonate resin (b) as specified by ISO 15184;
[0016] (ii) the glass transition point Tg(a) of the polycarbonate
resin (a) and the glass transition point Tg(b) of the polycarbonate
resin (b) satisfy the relation of the following (Formula 1):
Tg(b)-45.degree. C.<Tg(a)<Tg(b)-10.degree. C. (Formula 1)
and
[0017] (iii) the pencil hardness of the polycarbonate resin
composition as specified by ISO 15184 is higher by at least two
ranks than the pencil hardness of the polycarbonate resin (b) as
specified by ISO 15184.
<2> A polycarbonate resin composition comprising at least a
polycarbonate resin (a) and a polycarbonate resin (b) having
structural units different from the polycarbonate resin (a), which
satisfies the following requirements:
[0018] (i) the pencil hardness of the polycarbonate resin (a) as
specified by ISO 15184 is higher than the pencil hardness of the
polycarbonate resin (b) as specified by ISO 15184; and
[0019] (ii) the ratio of the intrinsic viscosity [.eta.](a) of the
polycarbonate resin (a) to the intrinsic viscosity [.eta.](b) of
the polycarbonate resin (b), [.eta.](a)/[.eta.](b), is at least 0.1
and at most 0.65.
<3> The polycarbonate resin composition according to the
above <1> or <2>, wherein the ratio of the viscosity
average molecular weight Mv(a) of the polycarbonate resin (a) to
the viscosity average molecular weight Mv(b) of the polycarbonate
resin (b), Mv(a)/Mv(b), is at least 0.1 and at most 2.0. <4>
The polycarbonate resin composition according to any one of the
above <1> to <3>, wherein the weight ratio of the
polycarbonate resin (a) to the polycarbonate resin (b) in the
polycarbonate resin composition is within a range of from 1:99 to
45:55. <5> The polycarbonate resin composition according to
any one of the above <1> to <4>, wherein the pencil
hardness of the polycarbonate resin (a) as specified by ISO 15184
is at least F. <6> The polycarbonate resin composition
according to any one of the above <1> to <5>, wherein
the pencil hardness of the polycarbonate resin composition as
specified by ISO 15184 is at least HB. <7> The polycarbonate
resin composition according to any one of the above <1> to
<6>, wherein the above Tg(a) and Tg(b) satisfy the relation
of the following (Formula 2):
Tg(b)-30.degree. C.<Tg(a)<Tg(b)-15.degree. C. (Formula 2)
<8> The polycarbonate resin composition according to any one
of the above <1> to <7>, wherein the polycarbonate
resin (a) is a polycarbonate resin having at least structural units
derived from a compound represented by the following formula
(1):
##STR00001##
wherein each of R.sup.1 and R.sup.2 which are independent of each
other, is a substituted or non-substituted C.sub.1-20 alkyl group
or a substituted or non-substituted aryl group, each of R.sup.3 and
R.sup.4 which are independent of each other, is a hydrogen atom, a
substituted or non-substituted C.sub.1-20 alkyl group or a
substituted or non-substituted aryl group, and X is a single bond,
a carbonyl group, a substituted or non-substituted alkylidene
group, an oxidized or non-oxidized sulfur atom, or an oxygen atom.
<9> The polycarbonate resin composition according to any one
of the above <1> to <8>, wherein the polycarbonate
resin (a) is a polycarbonate resin having at least structural units
derived from at least one compound selected from the group
consisting of the following formulae (1a) to (1c):
##STR00002##
<10> The polycarbonate resin composition according to any one
of the above <1> to <9>, wherein the polycarbonate
resin (b) is a polycarbonate resin having mainly structural units
derived from a compound represented by the following formula
(2):
##STR00003##
<11> The polycarbonate resin composition according to any one
of the above <1> to <10>, which has a yellowness index
(YI) of at most 4.0. <12> The polycarbonate resin composition
according to any one of the above <1> to <11>, which
further contains a flame retardant. <13> A method for
producing the polycarbonate resin composition as defined in any one
of the above <1> to <12>, which comprises melt-kneading
the polycarbonate resin (a) and the polycarbonate resin (b).
<14> A method for producing the polycarbonate resin
composition as defined in any one of the above <1> to
<12>, which comprises dry-blending the polycarbonate resin
(a) and the polycarbonate resin (b). <15> An injection-molded
article, which is obtained by injection-molding the polycarbonate
resin composition as defined in any one of the above <1> to
<12>. <16> An extruded article, which is obtained by
extruding the polycarbonate resin composition as defined in any one
of the above <1> to <12>. <17> The extruded
article according to the above <16>, which is a sheet or a
film. <18> A molded article of polycarbonate resin,
comprising the polycarbonate resin composition as defined in any
one of the above <8> to <12>, wherein the ratio of the
content [S] of the structural units (a) derived from a compound
represented by the following formula (1) on the surface of the
molded article of polycarbonate resin to the content [T] in the
entire molded article of polycarbonate resin ([S]/[T]) is higher
than 1.00 and at most 2.00:
##STR00004##
wherein each of R.sup.1 and R.sup.2 which are independent of each
other, is a substituted or non-substituted C.sub.1-20 alkyl group
or a substituted or non-substituted aryl group, each of R.sup.3 and
R.sup.4 which are independent of each other, is a hydrogen atom, a
substituted or non-substituted C.sub.1-20 alkyl group or a
substituted or non-substituted aryl group, and X is a single bond,
a carbonyl group, a substituted or non-substituted alkylidene
group, an oxidized or non-oxidized sulfur atom, or an oxygen atom.
<19> The molded article of polycarbonate resin according to
the above <18>, which is an injection-molded article.
<20> The molded article of polycarbonate resin according to
the above <18> or <19>, wherein the ratio of the
content [S] of the structural units (a) on the surface of the
molded article of polycarbonate resin to the content [T] in the
entire molded article of polycarbonate resin ([S]/[T]) is at least
1.01 and at most 1.50. <21> The molded article of
polycarbonate resin according to any one of the above <18> to
<20>, wherein the pencil hardness on the surface of the
molded article of polycarbonate resin as specified by ISO 15184 is
at least HB. <22> The molded article of polycarbonate resin
according to any one of the above <18> to <21>, wherein
the structural units (a) are structural units derived from at least
one compound selected from the group consisting of the following
formulae (1a) to (1c):
##STR00005##
<23> The molded article of polycarbonate resin according to
any one of the above <18> to <22>, wherein the
polycarbonate resin (b) is a polycarbonate resin having mainly
structural units (b) derived from a compound represented by the
following formula (2):
##STR00006##
<24> The molded article of polycarbonate resin according to
any one of the above <18> to <23>, which comprises at
least a polycarbonate resin (a) having structural units (a) derived
from a compound represented by the formula (1) and a polycarbonate
resin (b) having structural units (b) different from the structural
units (a) and having a structure different from the polycarbonate
resin (a). <25> The molded article of polycarbonate resin
according to any one of the above <18> to <24>, wherein
the pencil hardness of the polycarbonate resin (a) as specified by
ISO 15184 is higher than the pencil hardness of the polycarbonate
resin (b) as specified by ISO 15184. <26> The molded article
of polycarbonate resin according to any one of the above <18>
to <25>, wherein the pencil hardness of the polycarbonate
resin (a) as specified by ISO 15184 is at least F. <27> The
molded article of polycarbonate resin according to any one of the
above <18> to <26>, wherein the viscosity average
molecular weight of the polycarbonate resin (a) is higher than the
viscosity average molecular weight of the polycarbonate resin (b).
<28> A method for producing the molded article of
polycarbonate resin as defined in any one of the above <18>
to <27>, comprising at least a polycarbonate resin (a) having
structural units (a) derived from a compound represented by the
following formula (1) and a polycarbonate resin (b) having
structural units (b) different from the structural units (a), which
comprises melt-kneading or dry-blending the polycarbonate resin (a)
and the polycarbonate resin (b), followed by molding, wherein the
viscosity average molecular weight of the polycarbonate resin (a)
is higher than the viscosity average molecular weight of the
polycarbonate resin (b):
##STR00007##
wherein each of R.sup.1 and R.sup.2 which are independent of each
other, is a substituted or non-substituted C.sub.1-20 alkyl group
or a substituted or non-substituted aryl group, each of R.sup.3 and
R.sup.4 which are independent of each other, is a hydrogen atom, a
substituted or non-substituted C.sub.1-20 alkyl group or a
substituted or non-substituted aryl group, and X is a single bond,
a carbonyl group, a substituted or non-substituted alkylidene
group, an oxidized or non-oxidized sulfur atom, or an oxygen atom.
<29> The method for producing the molded article of
polycarbonate resin according to the above <28>, wherein the
structural units (a) are structural units derived from at least one
compound selected from the group consisting of the following
formulae (1a) to (1c):
##STR00008##
<30> The method for producing the molded article of
polycarbonate resin according to the above <28> or
<29>, wherein the structural units (b) are mainly structural
units derived from a compound of the following formula (2):
##STR00009##
<31> The method for producing the molded article of
polycarbonate resin according to any one of the above <28> to
<30>, wherein the molding is injection-molding.
Advantageous Effects of Invention
[0020] According to the present invention, it is possible to obtain
a polycarbonate resin composition having a particularly excellent
surface hardness, having favorable flame retardancy, and having
excellent heat resistance, moldability (fluidity), color, impact
resistance and the like. That is, by a polycarbonate resin
composition comprising a polycarbonate resin (b) and a
polycarbonate resin (a) having a specific glass transition point,
effects of increasing the surface hardness and the like can be
obtained, without impairing the physical properties of the
polycarbonate resin (b). For example, in a case where a bisphenol A
type polycarbonate resin is used as the polycarbonate resin (b),
the surface hardness which is a disadvantage of the bisphenol A
type polycarbonate resin can be improved while minimizing a
decrease in the impact resistance, the transparency, the color and
the like which are characteristics of the bisphenol A type
polycarbonate resin.
DESCRIPTION OF EMBODIMENTS
[0021] The polycarbonate resin composition of the present invention
is a polycarbonate resin composition comprising at least a
polycarbonate resin (a) and a polycarbonate resin (b) having
structural units different from the polycarbonate resin (a), which
satisfies the after-mentioned requirements (i) to (iii).
[0022] First, the requirement (i) is that the pencil hardness of
the polycarbonate resin (a) constituting the polycarbonate resin
composition of the present invention as specified by ISO 15184 is
higher than the pencil hardness of the polycarbonate resin (b) as
specified by ISO 15184.
[0023] The pencil hardness of the polycarbonate resin or the
polycarbonate resin composition specified in the present invention
is the pencil hardness measured in the form of an injection-molded
article, as described in the evaluation method "(1) pencil hardness
of molded article" in Examples in detail. Hereinafter, in this
specification, "the pencil hardness" means this pencil hardness of
an injection-molded article, unless otherwise specified.
[0024] If the pencil hardness of the polycarbonate resin (a) is
equal to or lower than the pencil hardness of the polycarbonate
resin (b), the pencil hardness of the polycarbonate resin
composition may be low, and the surface of a molded article is
likely to be scarred.
[0025] A favorable pencil hardness of the polycarbonate resin (a)
is at least F by the pencil hardness as specified by ISO 15184. If
the pencil hardness of the polycarbonate resin (a) is less than F,
the pencil hardness of the polycarbonate resin composition may not
sufficiently be improved in some cases.
[0026] As the requirement (ii), it is required that the glass
transition point Tg(a) of the polycarbonate resin (a) and the glass
transition point Tg(b) of the polycarbonate resin (b) satisfy the
relation of the following (Formula 1):
Tg(b)-45.degree. C.<Tg(a)<Tg(b)-10.degree. C. (Formula 1)
[0027] Here, if Tg(a) is equal to or lower than Tg(b)-45.degree.
C., the glass transition temperature of the obtainable
polycarbonate resin composition tends to be too low, thus lowering
the heat resistance in some cases. On the other hand, if Tg(a) is
equal to or higher than Tg(b)-10.degree. C., the effect of
increasing the surface hardness of the obtainable polycarbonate
resin composition tends to be small, and as a result, the surface
may easily be scarred. Further, the melt viscosity of the
obtainable polycarbonate resin composition may be high, whereby the
fluidity tends to be low, the moldability tend to be poor, and no
favorable molded article may be obtained.
[0028] Particularly from the viewpoint of the balance between the
heat resistance and the moldability, Tg(a) and Tg(b) preferably
satisfy the relation of the following (Formula 2):
Tg(b)-30.degree. C.<Tg(a)<Tg(b)-15.degree. C. (Formula 2)
[0029] As the requirement (iii), it is essential that the pencil
hardness of the polycarbonate resin composition of the present
invention as specified by ISO 15184 is higher by at least two ranks
than the pencil hardness of the polycarbonate resin (b) as
specified by ISO 15184, and it is preferably higher by at least
three ranks.
[0030] The pencil hardness ranks are, from lower ranks, 2B, B, HB,
F, H, 2H, 3H and 4H, and the pencil hardness of the polycarbonate
resin composition as specified by ISO 15184 being higher by at
least two ranks than the pencil hardness of the polycarbonate resin
(b) as specified by ISO 15184 means, for example, a pencil hardness
of at least HB when the pencil hardness of the polycarbonate resin
(b) as specified by ISO 15184 is 2B, a pencil hardness of at least
F when the pencil hardness of the polycarbonate resin (b) is B, and
a pencil hardness of at least H when the pencil hardness of the
polycarbonate resin (b) as specified by ISO 15184 is HB.
[0031] If the pencil hardness of the polycarbonate resin
composition as specified by ISO 15184 is not higher by at least two
ranks than the pencil hardness of the polycarbonate resin (b) as
specified by ISO 15184, the pencil hardness of the polycarbonate
resin composition as specified by ISO 15184 may be low, and the
surface of the molded article is likely to be scarred in some
cases.
[0032] Further, the polycarbonate resin composition of the present
invention is a polycarbonate resin composition comprising at least
a polycarbonate resin (a) and a polycarbonate resin (b) having
structural units different from the above polycarbonate resin,
which satisfies the after-mentioned requirements (1) and (2).
[0033] First, the requirement (1) is that the pencil hardness of
the polycarbonate resin (a) constituting the polycarbonate resin
composition of the present invention as specified by ISO 15184 is
higher than the pencil hardness of the polycarbonate resin (b) as
specified by ISO 15184.
[0034] If the pencil hardness of the polycarbonate resin (a) is
equal to or lower than the pencil hardness of the polycarbonate
resin (b), the pencil hardness of the polycarbonate resin
composition may be low, and the surface of a molded article is
likely to be scarred.
[0035] A favorable pencil hardness of the polycarbonate resin (a)
is at least F by the pencil hardness as specified by ISO 15184. If
the pencil hardness of the polycarbonate resin (a) is less than F,
the pencil hardness of the polycarbonate resin composition may not
sufficiently be improved in some cases.
[0036] As the requirement (2), the ratio of the intrinsic viscosity
[.eta.](a) of the polycarbonate resin (a) to the intrinsic
viscosity [.eta.](b) of the polycarbonate resin (b),
[.eta.](a)/[.eta.](b), is required to be within a range of at least
0.1 and at most 0.65, preferably within a range of at least 0.15
and at most 0.6.
[0037] If [.eta.](a)/[.eta.](b) is too low, the surface hardness of
the polycarbonate resin composition may not sufficiently be
improved, and if [.eta.](a)/[.eta.](b) is too high, the melt
viscosity of the polycarbonate resin composition may be too high,
whereby the fluidity may be decreased, and the moldability may be
low.
[0038] In the present invention, "having different structural
units" means [I] "having different types of structural units" in a
case where each of the polycarbonate resin (a) and the
polycarbonate resin (b) is a homopolymer, and means [II] (A) having
different types of structural units or (B) having the same type of
structural units and having a different compositional ratio of the
structural units in a case where at least one of the polycarbonate
resin (a) and the polycarbonate resin (b) is a copolymer.
[0039] That is, a specific example of the above [I] is a case where
the polycarbonate resin (a) is a homopolymer comprising structural
units (a) and the polycarbonate resin (b) is a homopolymer
comprising structural units (b).
[0040] A specific example of [II] (A) is a case where the
polycarbonate resin (a) is a copolymer comprising structural units
(a) and structural units (c), and the polycarbonate resin (b) is a
copolymer comprising structural units (b) and structural units
(c).
[0041] A specific example of the above [II] (B) is a case where
each of the polycarbonate resin (a) and the polycarbonate resin (b)
comprises structural units (a) and structural units (b), however,
the polycarbonate resin (a) and the polycarbonate resin (b) are
different in the ratio of the structural units (a) to the
structural units (b).
[0042] Further, the structural units (c) are structural units
different from both the structural units (a) and the structural
units (b).
[0043] The present invention relates to a molded article of
polycarbonate resin having structural units (a) derived from a
compound represented by the following formula (1) and structural
units (b) different from the structural units (a), wherein the
ratio of the content [S] of the structural units (a) on the surface
of the molded article of polycarbonate resin to the content [T] in
the entire molded article of polycarbonate resin ([S]/[T]) is
higher than 1.00 and at most 2.00:
##STR00010##
wherein each of R.sup.1 and R.sup.2 which are independent of each
other, is a substituted or non-substituted C.sub.1-20 alkyl group
or a substituted or non-substituted aryl group, each of R.sup.3 and
R.sup.4 which are independent of each other, is a hydrogen atom, a
substituted or non-substituted C.sub.1-20 alkyl group or a
substituted or non-substituted aryl group, and X is a single bond,
a carbonyl group, a substituted or non-substituted alkylidene
group, an oxidized or non-oxidized sulfur atom, or an oxygen
atom.
[0044] The present invention is characterized in that in the molded
article of polycarbonate resin having the above two types of
structural units, the ratio of the content [S] of the structural
units (a) on the surface of the molded article of polycarbonate
resin to the content [T] in the entire molded article of
polycarbonate resin ([S]/[T]) is higher than 1.00 and at most 2.00,
preferably at least 1.01 and at most 1.50, further preferably at
least 1.10 and at most 1.20.
[0045] That is, in the molded article of polycarbonate resin of the
present invention, the content of the structural units (a) on the
surface of the molded article of polycarbonate resin is higher than
the content of the structural units (a) in the entire molded
article of polycarbonate resin.
[0046] As mentioned above, a molded article of polycarbonate resin
containing a larger amount of the structural units (a) on the
surface of the molded article of polycarbonate resin, has a
remarkably improved surface hardness, has a favorable color, and
has improved impact resistance.
[0047] Particularly when the above [S]/[T] is at least 1.01 and at
most 1.50, a molded article of polycarbonate resin which is more
excellent in the surface hardness and the impact resistance will be
obtained.
[0048] The content [S] of the structural units (a) on the surface
of the molded article of polycarbonate resin and the content [T] of
the structural units (a) in the entire molded article of
polycarbonate resin can be obtained by an NMR method. More
specifically, the molar composition of each structural units can be
obtained by the integrated intensity ratio of signals
characteristics of a dihydroxy compound observed by .sup.1H-NMR
measurement of a deuterochloroform solution of the molded article
of polycarbonate resin using a nuclear magnetic resonance apparatus
(NMR apparatus). The weight ratio of each structural units is
determined from the obtained molar composition and the formula
weight of each structural units.
[0049] Specific methods of obtaining the content [S] of the
structural units (a) on the surface of the molded article of
polycarbonate resin and the content [T] of the structural units (a)
in the entire molded article of polycarbonate resin are as
follows.
(I) Content [S] of Structural Units (a) on the Surface of Molded
Article of Polycarbonate Resin
[0050] The entire molded article of polycarbonate resin is immersed
in methylene chloride at room temperature (25.degree. C.). 5
Seconds after initiation of immersion, the molded article of
polycarbonate resin is taken out from methylene chloride to obtain
a methylene chloride solution. Methylene chloride is removed from
the methylene chloride solution to obtain a residue. The residue is
dissolved in deuterochloroform, and the obtained solution is
subjected to measurement by .sup.1H-NMR method.
[0051] From the signal intensity of the structural units (a) and
the signal intensities of other structural units in the obtained
.sup.1H-NMR spectrum, the proportion of the structural units (a) to
all the structural units obtained in total is calculated and
regarded as the content [S] (wt %) of the structural units (a) on
the surface of the molded article of polycarbonate resin.
(II) Content [T] of Structural Units (a) in the Entire Molded
Article of Polycarbonate Resin
[0052] The entire molded article of polycarbonate resin is immersed
in methylene chloride at room temperature (25.degree. C.) and
completely dissolved to obtain a methylene chloride solution. About
50 g of the methylene chloride solution is taken, and methylene
chloride is removed from the methylene chloride solution to obtain
a residue. The residue is dissolved in deuterochloroform, and the
obtained solution is subjected to measurement by .sup.1H-NMR
method.
[0053] From the signal intensity of the structural units (a) and
the signal intensities of other structural units in the obtained
.sup.1H-NMR spectrum, the proportion of the structural units (a) to
all the structural units obtained in total is calculated and
regarded as the content [T] (wt %) of the structural units (a) in
the entire molded article.
[0054] The molded article of polycarbonate resin of the present
invention is preferably an injection-molded article.
[0055] An injection-molded article has advantages in that molded
articles having a complicated shape can be molded in a high cycle
rate.
[0056] The Charpy impact strength of the molded article of
polycarbonate resin of the present invention is properly determined
depending upon the shape, the purpose of use and the like of a
final article, and is usually at least 8 kJ/m.sup.2, preferably at
least 10 kJ/m.sup.2. If the Charpy impact strength is less than 8
kJ/m.sup.2, the molded article of polycarbonate resin tends to be
easily broken. The Charpy impact strength of the molded article of
polycarbonate resin can be determined by a measurement method based
on JIS K7111. The specific measurement method will be described in
detail in Examples.
(Content of Structural Units in Molded Article of Polycarbonate
Resin)
[0057] The content (average content) of the structural units (a) in
the molded article of polycarbonate resin of the present invention
is not particularly limited, and is usually less than 50 wt %,
preferably at most 20 wt %, based on 100 wt % of all the structural
units (the total of the structural units (a), the structural units
(b) and other structural units) constituting the polycarbonate
resin. Further, the lower limit of the content of the structural
units (a) is 1 wt %.
[0058] The content of the structural units in the molded article of
polycarbonate resin can be obtained by the NMR method, as described
above.
[0059] The molded article of polycarbonate resin of the present
invention is preferably a molded article of polycarbonate resin
comprising at least a polycarbonate resin (a) having structural
units (a) derived from a compound represented by the above formula
(1) and a polycarbonate resin (b) having structural units (b)
different from the structural units (a) and having a structure
different from the polycarbonate resin (a), in view of easy
production.
[0060] The polycarbonate resin (b) is a polycarbonate resin having
structural units (b) different from the structural units (a) and
having a structure different from the polycarbonate resin (a). That
is, the polycarbonate resin (b) has "a structure different" from
the polycarbonate resin (a) not only when the polycarbonate resin
(a) is a homopolymer comprising structural units (a) and the
polycarbonate resin (b) is a homopolymer comprising structural
units (b), but also when the polycarbonate resin (b) is a copolymer
having structural units (a) as structural units other than the
structural units (b).
[0061] Further, in a case where the molded article of polycarbonate
resin of the present invention comprises the above polycarbonate
resin (a) and polycarbonate resin (b), the viscosity average
molecular weight of the polycarbonate resin (a) is preferably
higher than the viscosity average molecular weight of the
polycarbonate resin (b). It is estimated that a molded article of
polycarbonate resin having a different content of the structural
units between on the surface of the molded article of polycarbonate
resin and in the interior of the molded article of polycarbonate
resin can be obtained by such a difference in the viscosity average
molecular weight.
[0062] Further, in the polycarbonate resin composition of the
present invention, the ratio of the viscosity average molecular
weight Mv(a) of the polycarbonate resin (a) to the viscosity
average molecular weight Mv(b) of the polycarbonate resin (b),
Mv(a)/Mv(b), is preferably at least 0.1 and at most 2.0, more
preferably at least 0.4 and at most 1.8. If Mv(a)/Mv(b) is low, the
impact resistance may be decreased. Further, if Mv(a)/Mv(b) is
high, the effect of improving the surface hardness tends to be
small, and the surface hardness of the polycarbonate resin
composition may be low. Further, the melt viscosity tends to be
very high, whereby the fluidity will be deteriorated and the
moldability is poor in some cases.
[0063] The viscosity average molecular weight Mv(a) of the
polycarbonate resin (a) is usually within a range of from 1,000 to
100,000, preferably from 3,000 to 50,000, more preferably from
5,000 to 30,000, further preferably from 5,000 to 20,000, most
preferably from 6,000 to 15,000. If Mv(a) is too high, the melt
viscosity of the polycarbonate resin composition tends to be high,
and the effect of improving the surface hardness may be small, such
being unfavorable. Further, if Mv(a) is too low, the effect of
improving the surface hardness of the polycarbonate resin
composition tends to be small, and the impact resistance, the
strength and the like may be low in some cases, such being
unfavorable.
[0064] The viscosity average molecular weight Mv(b) of the
polycarbonate resin (b) is usually within a range of from 1,000 to
100,000, preferably from 5,000 to 50,000, more preferably from
10,000 to 40,000, further preferably from 15,000 to 30,000. If
Mv(b) is too high, the melt viscosity of the polycarbonate resin
composition tends to be high, and the fluidity may be decreased,
such being unfavorable. Further, if Mv(b) is too low, the effect of
improving the surface hardness of the resin composition tends to be
small, and the impact resistance, the strength and the like may be
low in some cases, such being unfavorable.
[0065] The weight ratio of the polycarbonate resin (a) to the
polycarbonate resin (b) in the polycarbonate resin composition is
preferably from 1:99 to 99:1, more preferably from 1:99 to 45:55,
further preferably from 5:95 to 40:60, particularly preferably from
10:90 to 30:70. If the proportion of the polycarbonate resin (a) is
high, a decrease in the impact resistance, a decrease in the heat
resistance and deterioration of the color may occur, and if the
proportion of the polycarbonate resin (a) is low, the pencil
hardness may be decreased.
[0066] The yellowness index (YI) of the polycarbonate resin
composition of the present invention is usually at most 4.0,
preferably at most 3.5, further preferably at most 3.0,
particularly preferably at most 2.5. If YI is too high, the color
tends to be deteriorated, the design as a molded article tends to
be poor, and particularly in a molded article which is required to
be colored, the brightness may be insufficient, and the color may
be smoky.
[0067] The melt viscosity of the polycarbonate resin composition of
the present invention is preferably at most 15,000 Poise, more
preferably at most 11,000 Poise, further preferably at most 8,000
Poise, particularly preferably at most 5,000 Poise, at a
temperature of 280.degree. C. at a shear rate of 122 sec.sup.-1. If
the melt viscosity is at least 15,000 poise, the fluidity may
remarkably be decreased, and the moldability may be impaired. The
melt viscosity is a value measured by a capillary rheometer
"Capirograph 1C" (manufactured by Toyo Seiki Seisaku-sho,
Ltd.).
[0068] The pencil hardness of the polycarbonate resin composition
of the present invention as specified by ISO 15184 is usually at
least HB, preferably at least F, more preferably at least H. If the
pencil hardness is low, the surface hardness tends to be low, and
when the polycarbonate resin composition is molded into a molded
article, it is easily scarred in some cases.
[0069] The Charpy impact strength of the polycarbonate resin
composition is properly determined by e.g. the shape and the
application of a final article, and is usually at least 8. If it is
less than 8, the final article may easily be broken.
[0070] The polycarbonate resin (a) and the polycarbonate resin (b)
having structural units different from the polycarbonate resin (a)
are not particularly limited so long as the above requirements are
satisfied. As described above, the polycarbonate resin (a) is a
resin having a relatively high pencil hardness, and the
polycarbonate resin (b) is a resin having a relatively low pencil
hardness.
[0071] Now, polycarbonate resins suitable as the polycarbonate
resin (a) and the polycarbonate resin (b) having structural units
different from the polycarbonate resin (a), constituting the
polycarbonate resin composition of the present invention, will be
described.
<Polycarbonate Resin (a)>
[0072] As the polycarbonate resin (a), first, a polycarbonate resin
having at least structural units derived from a compound
represented by the following formula (1) may be mentioned as a
suitable example:
##STR00011##
wherein each of R.sup.1 and R.sup.2 which are independent of each
other, is a substituted or non-substituted C.sub.1-20 alkyl group
or a substituted or non-substituted aryl group, each of R.sup.3 and
R.sup.4 which are independent of each other, is a hydrogen atom, a
substituted or non-substituted C.sub.1-20 alkyl group or a
substituted or non-substituted aryl group, and X is a single bond,
a carbonyl group, a substituted or non-substituted alkylidene
group, an oxidized or non-oxidized sulfur atom, or an oxygen
atom.
[0073] In the above formula (1), as each of R.sup.1 and R.sup.2,
the substituted or non-substituted C.sub.1-20 alkyl group may, for
example, be a methyl, ethyl, n-propyl, isopropyl, n-butyl,
isobutyl, sec-butyl, tert-butyl, n-pentyl, sec-pentyl, n-hexyl,
n-heptyl or n-octyl group, and the substituted or non-substituted
aryl group may, for example, be a phenyl, benzyl, tolyl,
4-methylphenyl or naphthyl group.
[0074] As each of R.sup.3 and R.sup.4, the substituted or
non-substituted C.sub.1-20 alkyl group may, for example, be a
methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl,
tert-butyl, n-pentyl, sec-pentyl, n-hexyl, n-heptyl or n-octyl
group, and the substituted or non-substituted aryl group may, for
example, be a phenyl, benzyl, tolyl, 4-methylphenyl or naphthyl
group.
[0075] Among them, each of R.sup.1 and R.sup.2 is preferably a
methyl, ethyl, n-propyl or 4-methylphenyl group, particularly
preferably a methyl group. Each of R.sup.3 and R.sup.4 is
preferably a hydrogen atom, a methyl, ethyl, n-propyl or
4-methylphenyl group, particularly preferably a hydrogen atom.
Here, the bonding positions of R.sup.1, R.sup.2, R.sup.3 and
R.sup.4 in the formula (1) are optional positions selected from 2-,
3-, 5- and 6-positions relative to X on the phenyl rings, and are
preferably 3-position or 5-position.
[0076] Further, in the formula (1), in a case where X is a
substituted or non-substituted alkylidene group or a carbonyl
group, it is represented by the following structural formulae. As
X, the oxidized or not-oxidized sulfur atom may, for example, be
--S-- or --SO.sub.2--.
##STR00012##
wherein each of R.sup.5 and R.sup.6 which are independent of each
other, is a hydrogen atom, a substituted or non-substituted
C.sub.1-20 alkyl group or a substituted or non-substituted aryl
group, Z is a substituted or non-substituted C.sub.4-20 alkylene
group or a polymethylene group, and n is an integer of from 1 to
10.
[0077] As each of R.sup.5 and R.sup.6, the substituted or
non-substituted C.sub.1-20 alkyl group may, for example, be a
methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl,
tert-butyl, n-pentyl, sec-pentyl, n-hexyl, n-heptyl or n-octyl
group, and the substituted or non-substituted aryl group may, for
example, be a phenyl, benzyl, tolyl, 4-methylphenyl or naphthyl
group.
[0078] Among them, each of R.sup.5 and R.sup.6 is preferably a
methyl, ethyl, n-propyl or 4-methylphenyl group, particularly
preferably a methyl group. It is particularly preferred that both
of R.sup.5 and R.sup.6 are methyl groups and n is 1, that is, X in
the formula (1) is an isopropylidene group.
[0079] Z in the formula (1) is bonded to the carbon atom bonded to
the two phenyl groups, and forms a substituted or non-substituted
bivalent carbon ring. The bivalent carbon ring may, for example, be
a (preferably C.sub.4-12) cycloalkylidene group such as a
cyclopentylidene, cyclohexylidene, cycloheptylidene,
cyclododecylidene or adamantylidene group, and the substituted
carbon ring may, for example, be such a group having a methyl
substituent or an ethyl substituent. Among them, preferred is a
cyclohexylidene group, a methyl-substituted cyclohexylidene group
or a cyclododecylidene group.
[0080] Among polycarbonate resins (a) having at least structural
units derived from a compound represented by the above formula (1),
a polycarbonate resin having structural units derived from at least
one compound selected from the group consisting of the following
formulae (1a) to (1i) is suitably used.
##STR00013## ##STR00014##
[0081] Among the above compounds, a polycarbonate resin having
structural units derived from at least one compound selected from
the group consisting of the above formulae (1a) to (1c) is more
suitably used.
[0082] The polycarbonate resin (a) may contain structural units
other than the structural units derived from the compound
represented by the above formula (1), within a range not to impair
the performance.
[0083] Such structural units are not particularly limited and may,
for example, be specifically structural units derived from an
alicyclic dihydroxy compound such as
2,2-bis(4-hydroxyphenyl)propane (hereinafter sometimes referred to
as "bisphenol A") or absolute sugar alcohol, or a cyclic ether
compound such as spiroglycol.
[0084] From the viewpoint of easiness of production of the molded
article of polycarbonate resin of the present invention, the
content of the structural units (a) in the polycarbonate resin (a)
is preferably at least 50 wt %, more preferably at least 75 wt %,
particularly preferably at least 95 wt % (including 100 wt %) based
on 100 wt % of all the structural units in the polycarbonate resin
(a).
[0085] The content of the structural units in the polycarbonate
resin (a) can be obtained by the NMR method described in the above
molded article of polycarbonate resin.
<Polycarbonate Resin (b)>
[0086] Then, as the polycarbonate resin (b), a polycarbonate resin
having structural units derived from at least one compound selected
from the group consisting of the following formulae (2) to (13) is
suitably used, and a bisphenol A type polycarbonate resin having
mainly structural units derived from bisphenol A represented by the
following formula (2) is more suitably used.
[0087] Here, "having mainly structural units derived from bisphenol
A" means that among the structural units constituting the
polycarbonate resin (b), at least 50 wt %, preferably at least 80
wt %, more preferably at least 90 wt % are structural units derived
from bisphenol A.
[0088] Here, the polycarbonate resin (b) contains the structural
units (b) which are structural units other than the structural
units (a) and may have structural units other than the structural
units (b). Accordingly, the polycarbonate resin (b) may have
structural units (a) (that is, the polycarbonate resin (b) is a
copolymer having the structural units (a) and the structural units
(b)).
[0089] On the other hand, if the polycarbonate resin (b) contains a
large amount of the structural units (a), the color may be
deteriorated, or the impact strength may be decreased, and
accordingly, the proportion of the structural units (a) contained
in the polycarbonate resin (b) is preferably less than 50 wt %,
more preferably less than 25 wt %, and preferably less than 5 wt %
(including 0 wt %), based on 100 wt % of all the structural units
constituting the polycarbonate resin (b).
[0090] The content of the structural units in the polycarbonate
resin (b) can be obtained by the NMR method. Specifically, the
molar composition of each structural units can be obtained from the
integrated intensity ratio of signals characteristics of a
dihydroxy compound used when the polycarbonate resin (b) is
prepared, observed by .sup.1H-NMR measurement of a
deuterochloroform solution of the polycarbonate resin (b) using a
nuclear magnetic resonance apparatus (NMR apparatus). The weight
ratio of each structural units is determined from the obtained
molar composition and the formula weight of each structural
units.
##STR00015## ##STR00016##
<Method for Producing Polycarbonate Resin>
[0091] Now, the method for producing the polycarbonate resin (a)
and the polycarbonate resin (b) of the present invention will be
described below (hereinafter "the polycarbonate resin (a) and the
polycarbonate resin (b)" will generally be referred to as
"polycarbonate resin" in some cases.)
[0092] The polycarbonate resin of the present invention is
obtainable by polymerization by using a dihydroxy compound and a
carbonyl compound. Specifically, there are an interfacial
polycondensation method (hereinafter sometimes referred to as
"interfacial method") for producing a polycarbonate resin by
reacting a dihydroxy compound and carbonyl chloride (hereinafter
sometimes referred to as "CDC" or "phosgene" at an interface
between an organic phase and an aqueous phase which are not
miscible optionally, and a melt polycondensation method
(hereinafter sometimes referred to as "melt method") for producing
a polycarbonate resin by subjecting a dihydroxy compound and a
carbonyl compound to an ester exchange reaction in a molten state
in the presence of an ester exchange reaction catalyst.
[0093] Now, each of the interfacial method and the melt method may
specifically be described.
<Interfacial Method>
[0094] The polycarbonate resin of the present invention by the
interfacial method is usually obtained in such a manner that an
alkaline aqueous solution of a dihydroxy compound is prepared (raw
material preparation step), the interfacial polycondensation
reaction of the dihydroxy compound and phosgene (COCl.sub.2) is
carried out in an organic solvent in the presence of, for example,
an amine compound, as a condensation catalyst, followed by steps of
neutralization, washing with water and drying to obtain the
polycarbonate resin. Specifically, the polycarbonate resin
production process by the interfacial method comprises at least a
raw material preparation step of preparing raw materials such as a
monomer component, an oligomerization step to carry out an
oligomerization reaction, a polycondensation step of carrying out a
polycondensation reaction using the oligomer, a washing step of
washing the reaction liquid after the polycondensation reaction by
alkali washing, acid washing and water washing, a polycarbonate
resin isolation step of pre-concentrating the washed reaction
liquid and isolating the polycarbonate resin after granulation, and
a drying step of drying isolated polycarbonate resin particles.
[0095] In the interfacial method, usually an organic solvent is
used.
[0096] Now, the respective steps will be described.
(Raw Material Preparation Step)
[0097] In the raw material preparation step, in a raw material
preparation tank, a raw material of e.g. an alkaline aqueous
solution of a dihydroxy compound containing a dihydroxy compound,
an aqueous solution of a metal compound such as sodium hydroxide
(NaOH) or magnesium hydroxide (Mg(OH).sub.2), demineralized water
(DMW) and further as the case requires, a reducing agent such as
hydrosulfite (HS) is prepared.
(Dihydroxy Compound)
[0098] As the dihydroxy compound which is a raw material of the
polycarbonate resin of the present invention, specifically,
dihydroxy compounds represented by the formulae (1a) to (1i)
represented by the above formula (1) and the formulae (2) to (13)
may, for example, be mentioned.
(Metal Compound)
[0099] The metal compound is usually preferably a hydroxide, such
as sodium hydroxide, lithium hydroxide, potassium hydroxide,
magnesium hydroxide or calcium hydroxide. Among them, sodium
hydroxide is particularly preferred.
[0100] The proportion of the metal compound to the dihydroxy
compound is usually from 1.0 to 1.5 (equivalent ratio), preferably
from 1.02 to 1.04 (equivalent ratio). If the proportion of the
metal compound is excessively high or excessively low, such may
influence the terminal groups of the carbonate oligomer obtainable
in the after-mentioned oligomerization step, and as a result, the
polycondensation reaction tends to be abnormal.
(Oligomerization Step)
[0101] Then, in the oligomerization step, in a predetermined
reactor, the alkaline aqueous solution of the dihydroxy compound
prepared in the raw material preparation step and phosgene (CDC)
are subjected to a phosgene reaction of the dihydroxy compound in
the presence of an organic solvent such as methylene chloride
(CH.sub.2Cl.sub.2).
[0102] Then, to the mixed liquid after the phosgene reaction of the
dihydroxy compound, a condensation catalyst such as triethylamine
(TEA) and a chain stopper such as p-t-butylphenol (pTBP) are added,
to carry out an oligomerization reaction of the dihydroxy
compound.
[0103] Then, after further oligomerization reaction is allowed to
proceed, the oligomerization reaction liquid of the dihydroxy
compound is introduced into a predetermined static separation tank,
an organic phase containing the carbonate oligomer and an aqueous
phase are separated, and the separated organic phase is supplied to
a polycondensation step.
[0104] Here, the retention time in the oligomerization step after
the alkaline aqueous solution of the dihydroxy compound is supplied
to the reactor in which the phosgene reaction of the dihydroxy
compound is carried out until the oligomerization reaction liquid
enters the static separation tank, is usually at most 120 minutes,
preferably from 30 to 60 minutes.
(Phosgene)
[0105] Phosgene used in the oligomerization step is usually used in
the form of liquid or gas. The preferred amount of use of CDC in
the oligomerization step is properly selected depending upon the
reaction conditions, particularly the reaction temperature and the
concentration of the dihydroxy compound in the aqueous phase and is
not particularly limited. Usually, the amount of CDC is from 1 to 2
mol, preferably from 1.05 to 1.5 mol, per 1 mol of the dihydroxy
compound. If the amount of use of CDC is excessively large,
unreacted CDC tends to increase, and the units may remarkably be
deteriorated. Further, if the amount of use of CDC is excessively
small, the chloroformate group amount tends to be insufficient, and
no appropriate molecular weight elongation tends to be
conducted.
(Organic Solvent)
[0106] In the oligomerization step, usually an organic solvent is
used. The organic solvent may be any optional inert organic solvent
in which phosgene and reaction products such as the carbonate
oligomer and the polycarbonate resin are dissolved under the
reaction temperature and the reaction pressure in the
oligomerization step, and which is not miscible with water (or
which does not form a solution with water).
[0107] Such an inert organic solvent may, for example, be an
aliphatic hydrocarbon such as hexane or n-heptane; a chlorinated
aliphatic hydrocarbon such as dichloromethane, chloroform, carbon
tetrachloride, dichloroethane, trichloroethane, tetrachloroethane,
dichloropropane or 1,2-dichloroethylene; an aromatic hydrocarbon
such as benzene, toluene or xylene, a chlorinated aromatic
hydrocarbon such as chlorobenzene, o-dichlorobenzene or
chlorotoluene; or a substituted aromatic hydrocarbon such as
nitrobenzene or acetophenone.
[0108] Among them, a chlorinated hydrocarbon such dichloromethane
or chlorobenzene is suitably used. Such an inert organic solvent
may be used alone or as a mixture with another solvent.
(Condensation Catalyst)
[0109] The oligomerization reaction may be carried out in the
presence of a condensation catalyst. The timing of addition of the
condensation catalyst is preferably after CDC is consumed. The
condensation catalyst may optionally be selected among many
condensation catalysts which have been used for a two-phase
interfacial condensation method. It may, for example, be
trialkylamine, M-ethylpyrrolidone, N-ethylpiperidine,
N-ethylmorpholine, N-isopropylpiperidine or N-isopropylmorpholine.
Among them, triethylamine or N-ethylpiperidine is preferred.
(Chain Stopper)
[0110] In this embodiment, in the oligomerization step, usually a
monophenol is used as the chain stopper. The monophenol may, for
example, be phenol; a C.sub.1-20 alkylphenol such as
p-t-butylphenol or p-cresol; or a halogenated phenol such as
p-chlorophenol or 2,4,6-tribromophenol. The amount of use of the
monophenol is properly selected depending upon the molecular weight
of the obtainable carbonate oligomer, and is usually from 0.5 to 10
mol % based on the dihydroxy compound.
[0111] In the interfacial method, the molecular weight of the
polycarbonate resin is determined by the amount of addition of the
chain stopper such as the monophenol. Accordingly, the timing of
addition of the chain stopper is preferably between immediately
after completion of consumption of the carbonate-forming compound
and before the molecular weight elongation starts, with a view to
controlling the molecular weight of the polycarbonate resin.
[0112] If the monophenol is added when the carbonate-forming
compound coexists, a condensate of the monophenol (a diphenyl
carbonate) forms in a large amount, and no polycarbonate resin
having a desired molecular weight tends to be obtained. If the
timing of addition of the monophenol is too late, there may be such
drawbacks that the molecular weight control tends to be difficult,
the obtainable resin may have a specific shoulder on the low
molecular side in the molecular weight distribution, and sagging
may occur at the time of molding.
(Branching Agent)
[0113] Further, in the oligomerization step, an optional branching
agent may be used. Such a branching agent may, for example, be
2,4-bis(4-hydroxyphenylisopropyl)phenol,
2,6-bis(2-hydroxy-5-methylbenzyl)-4-methylphenol,
2-(4-hydroxyphenyl)-2-(2,4-dihydroxyphenyl)propane or
1,4-bis(4,4'-dihydroxytriphenylmethyl)benzene. Further,
2,4-dihydroxybenzoic acid, trimesic acid, cyanuric chloride or the
like may also be used. Among them, a branching agent having at
least three phenolic hydroxy groups is suitable. The amount of use
of the branching agent is properly selected depending upon the
degree of branching of the obtainable carbonate oligomer, and is
usually from 0.05 to 2 mol % based on the dihydroxy compound.
[0114] In the oligomerization step, in a case where the two-phase
interfacial condensation method is employed, it is preferred that
prior to contact of the alkali metal compound aqueous solution or
the alkaline earth metal compound aqueous solution of the dihydroxy
compound with phosgene, the organic phase containing the dihydroxy
compound and the aqueous phase containing the metal compound are
brought into contact with an organic phase not optionally mixed
with water, to form an emulsion.
[0115] As a means of forming such an emulsion, it is preferred to
use, for example, a mixing machine such as a stirring machine
having a predetermined stirring blade, a dynamic mixer such as a
homogenizer, a homomixer, a colloid mill, a flow jet mixer or an
ultrasonic emulsifier, or a static mixer. The emulsion usually has
a droplet size of from 0.01 to 10 .mu.m, and has emulsion
stability.
[0116] The emulsified state of the emulsion is usually represented
by the Weber number or P/q (driver power per unit volume). The
Weber number is preferably at least 10,000, more preferably at
least 20,000, most preferably at least 35,000. Further, as the
upper limit, at a level of at most 1,000,000 is enough. Further,
P/q is preferably at least 200 kgm/L, more preferably at least 500
kgm/L, most preferably at least 1,000 kg-m/L.
[0117] Contact of the emulsion with CDC is preferably carried out
under mixing conditions weaker than the above-described emulsifying
conditions, with a view to suppressing dissolution of CDC in the
organic phase. The Weber number is less than 10,000, preferably
less than 5,000, more preferably less than 2,000. Further, P/q is
less than 200 kgm/L, preferably less than 100 kgm/L, more
preferably less than 50 kgm/L. Contact with CDC can be achieved by
introducing CDC into a tubular reactor or a tank-form reactor.
[0118] The reaction temperature in the oligomerization step is
usually at most 80.degree. C., preferably at most 60.degree. C.,
further preferably within a range of from 10 to 50.degree. C. The
reaction time is properly selected depending upon the reaction
temperature, and is usually from 0.5 minute to 10 hours, preferably
from 1 minute to 2 hours. If the reaction temperature is
excessively high, the side reaction cannot be controlled, and the
CDC units tend to be deteriorated. If the reaction temperature is
excessively low, although such is preferred with a view to
controlling the reaction, the refrigeration load tends to increase,
thus leading to the cost increases.
[0119] The carbonate oligomer concentration in the organic phase
may be such a range that the obtainable carbonate oligomer is
soluble, and specifically, it is at a level of from 10 to 40 wt %.
The proportion of the organic phase is preferably from 0.2 to 1.0
by the volume ratio based on the aqueous phase containing the
aqueous solution of the metal compound salt of the dihydroxy
compound.
(Polycondensation Step)
[0120] Then, in the polycondensation step, the organic phase
containing the carbonate oligomer separated from the aqueous phase
in the static separation tank is transferred to an oligomer tank
having a stirring machine. In the oligomer tank, a condensation
catalyst such as triethylamine (TEA) is further added.
[0121] Then, the organic phase stirred in the oligomer tank is
introduced into a predetermined polycondensation reaction tank, and
then to the polycondensation reaction tank, demineralized water
(DMW), an organic solvent such as methylene chloride
(CH.sub.2Cl.sub.2) and a sodium hydroxide aqueous solution are
supplied, stirred and mixed to carry out a polycondensation
reaction of the carbonate oligomer.
[0122] The polycondensation reaction liquid in the polycondensation
reaction tank is then continuously introduced successively to a
plurality of polycondensation reaction tanks, whereby the
polycondensation reaction of the carbonate oligomer is
completed.
[0123] Here, in the polycondensation step, the retention time in
the polycondensation reaction tanks in which the polycondensation
reaction of the carbonate oligomer is continuously carried out is
usually at most 12 hours, preferably from 0.5 to 5 hours.
[0124] As a preferred embodiment of the polycondensation step,
first, the organic phase containing the carbonate oligomer and the
aqueous phase are separated, and as the case requires, an inert
organic solvent is added to the separated organic phase to adjust
the concentration of the carbonate oligomer. In such a case, the
amount of the inert organic solvent is adjusted so that the
concentration of the polycarbonate resin in the organic phase
obtainable by the polycondensation reaction is from 5 to 30 wt %.
Then, water and an aqueous solution containing a metal compound are
newly added, and further, to adjust the polycondensation
conditions, preferably a condensation catalyst is added, and the
polycondensation reaction is carried out in accordance with the
interfacial polycondensation method. The ratio of the organic phase
to the aqueous phase in the polycondensation reaction is preferably
such that the organic phase:the aqueous phase=1:0.2 to 1:1 by the
volume ratio.
[0125] As the metal compound, the same compound as one used in the
above-described oligomerization step may be mentioned.
Particularly, sodium hydroxide is industrially preferred. The
amount of use of the metal compound may be at least an amount with
which the reaction system is always alkaline during the
polycondensation reaction, and the entire amount may be added all
at once at the start of the polycondensation reaction, or the metal
compound may be added as properly divided during the
polycondensation reaction.
[0126] If the amount of use of the metal compound is excessively
large, a hydrolysis reaction as a side reaction tends to proceed.
Accordingly, the concentration of the metal compound contained in
the aqueous phase after completion of the polycondensation reaction
is preferably adjusted to be at least 0.05 N, preferably from 0.05
to 0.3 N.
[0127] The temperature of the polycondensation reaction in the
polycondensation step is usually in the vicinity of room
temperature. The reaction time is from 0.5 to 5 hours, preferably
at a level of from 1 to 3 hours.
(Washing Step)
[0128] Then, after completion of the polycondensation reaction in
the polycondensation reaction tanks, the polycondensation reaction
liquid is subjected to alkali washing with an alkaline washing
liquid, acid washing with an acid washing liquid and water washing
with washing water by a known method. The entire retention time in
the washing step is usually at most 12 hours, preferably from 0.5
to 6 hours.
(Polycarbonate Resin Isolation Step)
[0129] In the polycarbonate resin isolation step, first, the
polycondensation reaction liquid containing the polycarbonate resin
washed in the washing step is concentrated to a predetermined solid
content concentration to prepare a concentrated liquid. The solid
content concentration of the polycarbonate resin in the
concentrated liquid is usually from 5 to 35 wt %, preferably from
10 to 30 wt %.
[0130] Then, the concentrated liquid is continuously supplied to a
predetermined granulation tank, and stirred and mixed with
demineralized water (DMW) of a predetermined temperature. Further,
a granulation treatment of evaporating the organic solvent while
maintaining the suspended state in water is carried out to form a
water slurry containing polycarbonate resin granules.
[0131] Here, the temperature of demineralized water (DMW) is
usually from 37 to 67.degree. C., preferably from 40 to 50.degree.
C. Further, the solidification temperature of the polycarbonate
resin by the granulation treatment carried out in the granulation
tank is usually from 37 to 67.degree. C., preferably from 40 to
50.degree. C.
[0132] The water slurry containing a polycarbonate resin powder
continuously discharged from the granulation tank is then
continuously introduced into a predetermined separator, and water
is separated from the water slurry.
(Drying Step)
[0133] In the drying step, the polycarbonate resin powder after
water is separated from the water slurry in the separator, is
continuously supplied to a predetermined drying machine, made to
stay in a predetermined retention time and then continuously
withdrawn. The drying machine may, for example, be a fluidized bed
drying machine. Further, a plurality of fluidized bed drying
machines may be connected in series to carry out the drying
treatment continuously.
[0134] Here, the drying machine usually has a heating means such as
a heat medium jacket, and is maintained usually at from 0.1 to 1.0
MPa-G, preferably from 0.2 to 0.6 MPa-G, for example, by water
vapor, whereby the temperature of nitrogen (N.sub.2) which flows in
the drying machine is maintained usually at from 100 to 200.degree.
C., preferably from 120 to 180.degree. C.
<Melt Method>
[0135] Now, the melt method will be described.
(Dihydroxy Compound)
[0136] The dihydroxy compound as a raw material of the
polycarbonate resin of the present invention may be specifically
the same dihydroxy compound as described in the interfacial
method.
(Carbonic Diester)
[0137] The carbonic diester as the material of the polycarbonate
resin of the present invention may be a compound represented by the
following formula (14).
##STR00017##
[0138] In the formula (14), A' is a C.sub.1-10 linear, branched or
cyclic monovalent hydrocarbon group which may be substituted. Two
A's may be the same or different.
[0139] Furthermore, examples of a substituent in the A' include a
halogen atom, a C.sub.1-10 alkyl group, a C.sub.1-10 alkoxy group,
a phenyl group, a phenoxy group, a vinyl group, a cyano group, an
ester group, an amide group and a nitro group.
[0140] Specific examples of the carbonic diester compound include
diphenyl carbonate, a substituted diphenyl carbonate such as
ditolyl carbonate, a dialkyl carbonate such as dimethyl carbonate,
diethyl carbonate and di-t-butyl carbonate.
[0141] Among them, diphenyl carbonate (hereinafter sometimes
referred to as "DPC") and a substituted diphenyl carbonate are
preferred. Those carbonic diesters may be used alone or as a
mixture of two or more of them.
[0142] Furthermore, the carbonic diester compound may be replaced
by a dicarboxylic acid or a dicarboxylic ester in an amount of
preferably at most 50 mol %, more preferably at most 30 mol %. The
representative examples of the dicarboxylic acid or dicarboxylic
ester include terephthalic acid, isophthalic acid, diphenyl
terephthalate and diphenyl isophthalate. When the carbonic diester
is replaced by such a dicarboxylic acid or a dicarboxylic ester, a
polyester carbonate is obtained.
[0143] In the process for producing the polycarbonate resin of the
present invention by the melt method, as the amount of use of those
carbonic diesters (including the above substitutional dicarboxylic
acid or dicarboxylic ester; the same applies hereinafter), the
carbonic diester compound is used in a molar ratio of usually from
1.01 to 1.30 mol, preferably from 1.02 to 1.20 mol per 1 mol of the
dihydroxy compound. If the molar ratio of the carbonic diester is
excessively low, the ester exchange reaction rate tends to be
lowered, whereby production of a polycarbonate resin having a
desired molecular weight is difficult, or the terminal hydroxy
group concentration of the obtainable polycarbonate resin tends to
be high, thus deteriorating the thermal stability. Further, if the
molar ratio of the carbonic diester is excessively high, the ester
exchange reaction rate tends to be decreased, and production of a
polycarbonate resin having a desired molecular weight tends to be
difficult, and in addition, an amount of the carbonic diester
compound remaining in the resin becomes so large as to produce an
unpleasant odor during the molding process or from a molded
article, which is undesirable.
(Ester Exchange Catalyst)
[0144] The ester exchange catalyst used in the process for
producing the polycarbonate resin of the present invention by the
melt method, may be one of catalysts generally used in producing a
polycarbonate resin by an ester exchange method, and is not
particularly limited.
[0145] In general, examples of the catalyst include basic compounds
such as an alkali metal compound, an alkaline earth metal compound,
a beryllium compound, a magnesium compound, a basic boron compound,
a basic phosphorus compound, a basic ammonium compound, and an
amine compound. Among them, an alkali metal compound or an alkaline
earth metal compound is practically preferred. Those ester exchange
catalysts may be used alone or as a mixture of two or more of
them.
[0146] The amount of use of the ester exchange catalyst is usually
within a range of from 1.times.10.sup.-9 to 1.times.10.sup.-3 mol
per 1 mol of the entire dihydroxy compound. In order to obtain a
polycarbonate resin excellent in the moldability and the hue, the
amount of the ester exchange catalyst is, when an alkali metal
compound and/or an alkaline earth metal compound is used,
preferably from 1.0.times.10.sup.-8 to 1.times.10.sup.-4 mol, more
preferably from 1.0.times.10.sup.-8 mol to 1.0.times.10.sup.-5 mol,
particularly preferably from 1.0.times.10.sup.-7 mol to
5.0.times.10.sup.-6 mol, per 1 mol of all the dihydroxy compounds.
If the amount is smaller than the above lower limit, no
polymerization activity necessary to produce a polycarbonate resin
having a desired molecular weight will be obtained, and if it is
larger than the above upper limit, the polymer hue may be
deteriorated, or the amount of branching tends to be too large,
thus leading to a decrease in the fluidity, whereby no desired
polycarbonate resin having excellent melt properties will be
obtained.
[0147] Examples of the alkali metal compound include inorganic
alkali metal compounds such as hydroxides, carbonates and hydrogen
carbonate compounds of alkali metals; and organic alkali metal
compounds such as salts of alkali metals with alcohols, phenols or
organic carboxylic acids. Examples of the alkali metals include
lithium, sodium, potassium, rubidium and cesium.
[0148] Among such alkali metal compounds, a cesium compound is
preferred, and cesium carbonate, cesium hydrogen carbonate and
cesium hydroxide are particularly preferred.
[0149] Examples of the alkaline earth metal compound include
inorganic alkaline earth metal compounds such as hydroxides or
carbonates of alkaline earth metals; and salts of alkaline earth
metals with alcohols, phenols or organic carboxylic acids. Examples
of the alkaline earth metals include calcium, strontium and
barium.
[0150] Further, examples of the beryllium compound and magnesium
compound include inorganic metal compounds such as hydroxides or
carbonates of the metals; and salts of those metals with alcohols,
phenols or organic carboxylic acids.
[0151] Examples of the basic boron compound include a sodium salt,
a potassium salt, a lithium salt, a calcium salt, a magnesium salt,
a barium salt and a strontium salt of a boron compound. Examples of
the boron compound include tetramethyl boron, tetraethyl boron,
tetrapropyl boron, tetrabutyl boron, trimethylethyl boron,
trimethylbenzyl boron, trimethylphenyl boron, triethylmethyl boron,
triethylbenzyl boron, triethylphenyl boron, tributylbenzyl boron,
tributylphenyl boron, tetraphenyl boron, benzyltriphenyl boron,
methyltriphenyl boron and butyltriphenyl boron.
[0152] Examples of the basic phosphorus compound include trivalent
phosphorus compounds such as triethylphosphine,
tri-n-propylphosphine, triisopropylphosphine, tri-n-butylphosphine,
triphenylphosphine and tributylphosphine; and quaternary
phosphonium salts derived from those compounds.
[0153] Examples of the basic ammonium compound include
tetramethylammonium hydroxide, tetraethylammonium hydroxide,
tetrapropylammonium hydroxide, tetrabutylammonium hydroxide,
trimethylethylammonium hydroxide, trimethylbenzylammonium
hydroxide, trimethylphenylammonium hydroxide,
triethylmethylammonium hydroxide, triethylbenzylammonium hydroxide,
triethylphenylammonium hydroxide, tributylbenzylammonium hydroxide,
tributylphenylammonium hydroxide, tetraphenylammonium hydroxide,
benzyltriphenylammonium hydroxide, methyltriphenylammonium
hydroxide and butyltriphenylammonium hydroxide.
[0154] Examples of the amine compound include 4-aminopyridine,
2-aminopyridine, N,N-dimethyl-4-aminopyridine,
4-diethylaminopyridine, 2-hydroxypyridine, 2-methoxypyridine,
4-methoxypyridine, 2-dimethylaminoimidazole, 2-methoxyimidazole,
imidazole, 2-mercaptoimidazole, 2-methylimidazole and
aminoquinoline.
(Catalyst Deactivating Agent)
[0155] In the present invention, after completion of the ester
exchange reaction, a catalyst deactivating agent to neutralize and
deactivate the ester exchange catalyst may be added. The heat
resistance and the hydrolysis resistance of a polycarbonate resin
obtained by such a treatment will be improved.
[0156] Such a catalyst deactivating agent is preferably an acidic
compound having pKa of at most 3, such as sulfonic acid or a
sulfonate, and it may, for example, be specifically benzenesulfonic
acid, p-toluenesulfonic acid, methyl benzenesulfonate, ethyl
benzenesulfonate, propyl benzenesulfonate, butyl benzenesulfonate,
methyl p-toluenesulfonate, ethyl p-toluenesulfonate, propyl
p-toluenesulfonate or butyl p-toluenesulfonate.
[0157] Among them, p-toluenesulfonic acid or butyl
p-toluenesulfonate is suitably used.
[0158] The process for producing the polycarbonate resin by the
melt method is conducted by preparing a material mixture melt
containing the dihydroxy compound and the carbonic diester as
materials (raw material preparation step) and subjecting the
material mixture melt to a multi-stage polycondensation reaction in
a molten state in the presence of an ester exchange reaction
catalyst using a plurality of reaction tanks (polycondensation
step). The reaction method may be any of a batchwise method, a
continuous method and a combination of a batchwise method and a
continuous method. As the reaction tanks, a plurality of vertical
reaction tanks and as the case requires, at least one horizontal
stirring reaction tank successive thereto are used. Usually, these
reaction tanks are connected in series to carry out the treatment
continuously.
[0159] After the polycondensation step, a step of terminating the
reaction and evaporating and removing unreacted materials and
reaction by-products in the polycondensation reaction liquid, a
step of adding a thermal stabilizer, a mold release agent, a
colorant or the like, a step of forming the polycarbonate resin
into a predetermined particle size, or the like may properly be
added.
[0160] Now, the respective steps in the production process will be
described below.
[0161] (Raw Material Preparation Step)
[0162] The dihydroxy compound and the carbonic diester compound
used as raw materials of the polycarbonate resin are generally
prepared as a material mixture melt using a batchwise,
semibatchwise or continuous stirring tank type apparatus in an
atmosphere of an inert gas such as nitrogen or argon. In the case
of using bisphenol A as the dihydroxy compound and diphenyl
carbonate as the carbonic diester compound, for example, a
temperature of the molten mixture is selected from a range of
usually from 120 to 180.degree. C., preferably from 125 to
160.degree. C.
[0163] Now, a case of using bisphenol A as the dihydroxy compound
and diphenyl carbonate as the carbonic diester compound as
materials will be described as an example.
[0164] In this case, the ratio of the dihydroxy compound to the
carbonic diester compound is adjusted so that the carbonic diester
compound is in excess, and the carbonic diester compound is in a
proportion of usually from 1.01 to 1.30 mol, preferably from 1.02
to 1.20 mol, per 1 mol of the dihydroxy compound.
(Polycondensation Step)
[0165] Polycondensation of an ester exchange reaction between the
dihydroxy compound and the carbonic diester compound is
continuously conducted by a multiple-stage method of generally at
least two stages, preferably from 3 to 7 stages. Specific reaction
conditions of each stage are as follows: the temperature is from
150 to 320.degree. C., the pressure is from ordinary pressure to
0.01 Torr (1.3 Pa), and the average residence time is from 5 to 150
minutes.
[0166] The temperature and vacuum are generally set to become
higher stepwise within the above reaction conditions in each of the
reaction tanks of the multi-stage method, in order to effectively
discharge the monohydroxy compound such as phenol produced as a
by-product with the progress of the ester exchange reaction.
[0167] When the polycondensation step is conducted by the
multi-stage method, it is preferred to provide a plurality of
reaction tanks including vertical stirring reaction tanks to
increase the average molecular weight of the polycarbonate resin.
The number of reaction tanks is usually from 2 to 6, preferably
from 4 to 5.
[0168] Here, the reaction tanks may, for example, be stirring tank
type reaction tanks, thin-film reaction tanks, centrifugal
thin-film evaporation reaction tanks, surface renewal type twin
screw kneading reaction tanks, twin screw horizontal stirring
reaction tanks, wet wall type reaction tanks, porous plate type
reaction tanks in which polycondensation proceeds during a free
fall, and porous plate type reaction tanks provided with a wire, in
which polycondensation proceeds during a fall along a wire.
[0169] Examples of the type of the stirring blade in the vertical
stirring reaction tanks include a turbine blade, a paddle blade, a
Pfaudler blade, an anchor blade, a FULLZONE blade (manufactured by
Kobelco Eco-Solutions Co., Ltd.), a SANMELLER blade (manufactured
by MITSUBISHI HEAVY INDUSTRIES, LTD.), a MAXBLEND blade
(manufactured by SHI Mechanical & Equipment Inc.), a
helicalribbon blade, and a lattice type twisting blade
(manufactured by Hitachi Plant Technologies, Ltd.).
[0170] Further, the horizontal stirring reaction tank refers to a
reaction tank with a stirring blade a revolution axis of which is
horizontal (horizontal direction). Examples of the stirring blade
in the horizontal reaction tank include single shaft stirring
blades such as a disk type and a paddle type, and two shaft
stirring blades such as HVR, SCR and N-SCR (manufactured by
MITSUBISHI HEAVY INDUSTRIES, LTD.), Bivolak (manufactured by SHI
Mechanical & Equipment Inc.), and a spectacle-shaped blade and
a lattice type blade (manufactured by Hitachi Plant Technologies,
Ltd.).
[0171] Further, the ester exchange catalyst used for the
polycondensation of the dihydroxy compound and the carbonic diester
compound may be generally previously prepared as a solution. The
concentration of the catalyst solution is not particularly limited,
and it is adjusted to an optional concentration according to the
solubility of the catalyst in the solvent. As the solvent, acetone,
an alcohol, toluene, phenol, water or the like may properly be
selected.
[0172] In a case where water is selected as the solvent of the
catalyst, the properties of the water are not particularly limited
so long as kinds and concentrations of impurities contained therein
are constant. Usually, distilled water, deionized water or the like
is preferably used.
<Method for Producing Polycarbonate Resin Composition>
[0173] The method for producing the polycarbonate resin composition
comprising the polycarbonate resin (a) and the polycarbonate resin
(b) of the present invention is not particularly limited and may,
for example, be
[0174] (1) a method of melt-kneading the polycarbonate resin (a)
and the polycarbonate resin (b);
[0175] (2) a method of melt-kneading the polycarbonate resin (a) in
a molten state and the polycarbonate resin (b) in a molten
state;
[0176] (3) a method of mixing the polycarbonate resin (a) and the
polycarbonate resin (b) in a solution state, or
[0177] (4) a method of dry-blending the polycarbonate resin (a) and
the polycarbonate resin (b).
[0178] Now, the respective methods will be described.
(1) Method of Melt-Kneading Polycarbonate Resin (a) and
Polycarbonate Resin (b)
[0179] Pellets or granules of the polycarbonate resin (a) and
pellets or granules of the polycarbonate resin (b) are melt-kneaded
by using a mixing apparatus such as a kneader, a twin screw
extruder or a single screw extruder. The pellets or granules of the
polycarbonate resin (a) and the pellets or granules of the
polycarbonate resin (b) may preliminarily be mixed in a solid state
and then kneaded, or either one of them is preliminarily melted in
the above mixing apparatus, and the other polycarbonate resin is
added and kneaded. The temperature at which they are kneaded is not
particularly limited, and is preferably a temperature higher than
Tg of the polycarbonate resin (a), more preferably a temperature
higher than Tg of the polycarbonate resin (b). Usually, it is
preferably at least 240.degree. C., more preferably at least
260.degree. C., further preferably at least 280.degree. C. Further,
it is preferably at most 350.degree. C., particularly preferably at
most 320.degree. C. If the kneading temperature is too low, mixing
of the polycarbonate resin (a) and the polycarbonate resin (b) will
not be complete, and when a molded article is produced, there may
be dispersion of the hardness or the impact resistance, such being
unfavorable. Further, if the kneading temperature is too high, the
color of the polycarbonate resin composition may be deteriorated,
such being unfavorable.
(2) Method of Melt-Kneading Polycarbonate Resin (a) in Molten State
and Polycarbonate Resin (b) in Molten State
[0180] The polycarbonate resin (a) in a molten state and the
polycarbonate resin (b) in a molten state are mixed by means of a
mixing apparatus such as a stirring tank, a static mixer, a
kneader, a twin screw extruder or a single screw extruder. In this
case, for example, a polycarbonate resin obtained by the melt
polymerization method may be introduced into the above mixing
apparatus in a molten state without cooling and solidification. The
mixing temperature is not particularly limited, and is preferably
at a temperature higher than the glass transition temperature Tg(a)
of the polycarbonate resin (a), more preferably a temperature
higher than the glass transition temperature Tg(b) of the
polycarbonate resin (b). Usually, it is preferably at least
150.degree. C., more preferably at least 180.degree. C., further
preferably at least 200.degree. C. Further, it is preferably at
most 300.degree. C., particularly preferably at most 250.degree. C.
If the mixing temperature is low, mixing of the polycarbonate resin
(a) and the polycarbonate resin (b) will not be complete, and when
a molded article is produced, there may be dispersion of the
hardness or the impact resistance, such being unfavorable. Further,
if the mixing temperature is too high, the color of the
polycarbonate resin composition may be deteriorated, such being
unfavorable.
(3) Method of Mixing Polycarbonate Resin (a) and Polycarbonate
Resin (b) in Solution State
[0181] The polycarbonate resin (a) and the polycarbonate resin (b)
are dissolved in an appropriate solvent to form solutions, they are
mixed in a solution state and then a polycarbonate resin
composition is isolated. Such a proper solvent may, for example, be
an aliphatic hydrocarbon such as hexane or n-heptane; a chlorinated
aliphatic hydrocarbon such as dichloromethane, chloroform, carbon
tetrachloride, dichloroethane, trichloroethane, tetrachloroethane,
dichloropropane or 1,2-dichloroethylene; an aromatic hydrocarbon
such as benzene, toluene or xylene; or a substituted aromatic
hydrocarbon such as nitrobenzene or acetophenone. Among them, a
chlorinated hydrocarbon such as dichloromethane or chlorobenzene is
suitably used. Such a solvent may be used alone or as a mixture
with another solvent.
[0182] The mixing apparatus may, for example, be a stirring tank or
a static mixer. Further, the mixing temperature is not particularly
limited so long as the polycarbonate resin (a) and the
polycarbonate resin (b) are soluble, and is usually at most the
boiling point of the solvent used.
(4) Method of Dry-Blending Polycarbonate Resin (a) and
Polycarbonate Resin (b)
[0183] Pellets or granules of the polycarbonate resin (a) and
pellets or granules of the polycarbonate resin (b) are dry-blended
by using a tumbler, a super mixer, a Henschel mixer, a nauta mixer
or the like.
[0184] Among the above methods (1) to (4), preferred are the
methods (1) and (2) of melt-kneading the polycarbonate resin (a)
and the polycarbonate resin (b) and the method (4) of dry-blending
the polycarbonate resin (a) and the polycarbonate resin (b).
[0185] In production of the polycarbonate resin composition, in any
of the above methods, a pigment, a dye, a mold release agent, a
thermal stabilizer or the like may properly be added within a range
not to impair the objects of the present invention.
(Flame Retardant)
[0186] The flame retardant used in this embodiment may, for
example, be at least one member selected from the group consisting
of a metal sulfonate type flame retardant, a halogen-containing
compound type flame retardant, a phosphorus-containing compound
type flame retardant and a silicon-containing compound type flame
retardant. Among them, a metal sulfonate type flame retardant is
preferred.
[0187] The blending amount of the flame retardant used in this
embodiment is usually from 0.01 to 1 part by weight, preferably
from 0.05 to 1 part by weight per 100 parts by weight of the
polycarbonate.
[0188] The metal sulfonate type flame retardant may, for example,
be a metal aliphatic sulfonate or a metal aromatic sulfonate. The
metal of such a metal salt may, for example, be an alkali metal
such as sodium, lithium, potassium, rubidium or cesium; beryllium
or a magnesium such as magnesium; or an alkaline earth metal such
as calcium, strontium or barium. The metal sulfonate may be used
alone or as a mixture of two or more.
[0189] The metal sulfonate may, for example, be a metal aromatic
sulfone sulfonate or a metal perfluoroalkane sulfonate.
[0190] The metal aromatic sulfone sulfonate may, for example, be
specifically sodium diphenylsulfone-3-sulfonate, potassium
diphenylsulfone-3-sulfonate, sodium
4,4'-dibromodiphenyl-sulfone-3-sulfonate, potassium
4,4'-dibromodiphenyl-sulfone-3-sulfone, calcium
4-chloro-4'-nitrodiphenylsulfone-3-sulfonate, disodium
diphenylsulfone-3,3'-disulfonate or dipotassium
diphenylsulfone-3,3'-disulfonate.
[0191] The metal perfluoroalkane sulfonate may, for example, be
sodium perfluorobutane sulfonate, potassium perfluorobutane
sulfonate, sodium perfluoromethylbutane sulfonate, potassium
perfluoromethylbutane sulfonate, sodium perfluorooctane sulfonate,
potassium perfluorooctane sulfonate or a tetraethylammonium salt of
perfluorobutane sulfonate.
[0192] The halogen-containing compound type flame retardant may,
for example, be specifically tetrabromobisphenol A, tribromophenol,
brominated aromatic triazine, a tetrabromobisphenol A epoxy
oligomer, a tetrabromobisphenol A epoxy polymer, decabromodiphenyl
oxide, tribromoallyl ether, a tetrabromobisphenol A carbonate
oligomer, ethylenebistetrabromophthalimide,
decabromodiphenylethane, brominated polystyrene or
hexabromocyclododecane.
[0193] The phosphorus-containing compound type flame retardant may,
for example, be red phosphorus, covered red phosphorus, a
polyphosphate compound, a phosphate compound or a phosphazene
compound. Among them, the phosphate compound may, for example, be
specifically trimethyl phosphate, triethyl phosphate, tributyl
phosphate, trioctyl phosphate, tributoxyethyl phosphate, triphenyl
phosphate, tricresyl phosphate, cresyldiphenyl phosphate,
octyldiphenyl phosphate, diisopropylphenyl phosphate,
tris(chloroethyl)phosphate, tris(dichloropropyl)phosphate,
tris(chloropropyl)phosphate,
bis(2,3-dibromopropyl)-2,3-dichloropropyl phosphate,
tris(2,3-dibromopropyl)phosphate, bis(chloropropyl)monooctyl
phosphate, bisphenol A bisphosphate, hydroquinone bisphosphate,
resorcin bisphosphate or trioxybenzene triphosphate.
[0194] The silicon-containing compound type flame retardant may,
for example, be silicone varnish, a silicone resin wherein
substituents bonded to silicon atoms are an aromatic hydrocarbon
group and an aliphatic hydrocarbon group having at least 2 carbon
atoms, a silicone compound having a branched main chain and having
an aromatic group in the organic functional group contained, a
silicone powder having a polydiorganosiloxane polymer which may
have functional groups supported on the surface of a silica powder,
or an organopolysiloxane-polycarbonate copolymer.
[0195] The polycarbonate resin composition to which this embodiment
is applicable, which comprises a combination of the polycarbonate
resin having structural units represented by the above formula (1)
and the flame retardant, has flame retardancy improved as compared
with a resin composition using a polycarbonate resin obtainable by
using bisphenol A as a raw material monomer (hereinafter referred
to as "A-PC") for example.
[0196] The reason why the flame retardancy of the polycarbonate
resin composition to which this embodiment is applicable is
improved is not clearly understood, but is considered to be as
follows, with reference to a case of using a polycarbonate resin
obtained by using 2,2-bis(3-methyl-4-hydroxyphenyl)propane which is
an aromatic dihydroxy compound as the raw material monomer
(hereinafter referred to as "C-PC") as the polycarbonate resin
component, as an example.
[0197] That is, C-PC has a low thermal decomposition starting
temperature as compared with A-PC and is likely to be decomposed.
Thus, C-PC is quickly decomposed and graphitized, thus forming a
heat insulating layer (char), whereby flame retardancy is easily
attained. The low thermal decomposition starting temperature of
C-PC as compared with A-PC is influenced by the difference in the
structure of the bisphenol structure that "the 3-position of each
of the two benzene rings is substituted by a methyl group".
Particularly in a case where C-PC is produced by the
above-described melt method, when the polymerization reaction
proceeds in a molten state at high temperature and at high shear
strength, a branch is likely to form from the 3-position of each of
the phenyl rings of the bisphenol compound. Accordingly, the flame
retardancy is improved such that in a flame test, flaming drips are
suppressed.
[0198] Further, C-PC has a lowered packing density of molecular
chains as compared with A-PC and has molecular chains which are
rigid and hardly move, and thus the molded article of resin tends
to have a low shrinkage and a low linear expansion coefficient.
Thus, high dimensional stability of the molded article of resin is
expected.
[0199] The polycarbonate resin composition to which this embodiment
is applicable, which has such properties, is suitable for resin
members for which high dimensional accuracy is required, such as
chassis for precision instruments such as cellular phones and PCs;
housing for home electric appliances such as TVs; screen films;
exterior members of a multicolor molded article of resin of two or
more colors, such as glazing; and multilayered extruded articles
having at least two surface layers of building materials such as
carports, agricultural greenhouses and acoustic insulation
boards.
[0200] Further, the polycarbonate resin composition to which this
embodiment is applicable, with which a molded article of resin
having high hardness and improved flame retardancy can be obtained,
is suitable for applications of e.g. molded articles of resin
related to illumination such as LED, such as lamp lenses,
protective covers and diffusers; lenses for glasses, vending
machine buttons, and keys of e.g. mobile devices.
[0201] With the polycarbonate resin composition to which this
embodiment is applicable, various additives are blended as the case
requires. The additives may, for example, be a stabilizer, an
ultraviolet absorber, a mold release agent, a colorant, an
antistatic agent, a thermoplastic resin, a thermoplastic elastomer,
glass fibers, glass flakes, glass beads, carbon fibers,
Wollastonite, calcium silicate and aluminum borate whiskers.
[0202] The method of mixing the polycarbonate resin and the flame
retardant and the additives or the like blended as the case
requires is not particularly limited. In this embodiment, for
example, a method of mixing the polycarbonate resin in a solid
state such as pellets or a powder with the flame retardant and the
like, followed by kneading e.g. by an extruder, a method of mixing
the polycarbonate resin in a molten state and the flame retardant
and the like, and a method of adding the flame retardant and the
like during the polymerization reaction of the raw material monomer
by the melt method or the interfacial method, or when the
polymerization reaction is completed, may be mentioned.
<Method for Producing Molded Article of Polycarbonate
Resin>
[0203] The method for producing the molded article of polycarbonate
resin of the present invention is not particularly limited, and it
is suitable to employ a production method using the polycarbonate
resin (a) and the polycarbonate resin (b) each having a specific
viscosity average molecular weight, so as to improve the surface
hardness of the molded article of polycarbonate resin.
[0204] That is, the production method of the present invention is a
method for producing the molded article of polycarbonate resin,
comprising at least a polycarbonate resin (a) having structural
units (a) derived from a compound represented by the above formula
(1) and a polycarbonate resin (b) having structural units (b)
different from the structural units (a), which comprises
melt-kneading or dry-blending the polycarbonate resin (a) and the
polycarbonate resin (b), followed by molding, wherein the viscosity
average molecular weight (Mv(a)) of the polycarbonate resin (a) is
higher than the viscosity average molecular weight (Mv(b)) of the
polycarbonate resin (b).
<Method for Producing Molded Article>
[0205] To produce a molded article of resin from the polycarbonate
resin composition of the present invention, a conventional extruder
or injection molding machine is used. The molded article of
polycarbonate resin of the present invention is preferably molded
by injection molding using an injection molding machine, in view of
advantages such that molded articles of polycarbonate resins having
a complicated shape can be molded with a high cycle rate.
[0206] The barrel temperature in molding is preferably a
temperature higher than Tg(a), more preferably a temperature higher
than Tg(b). Usually, it is preferably at least 200.degree. C., more
preferably at least 250.degree. C., most preferably at least
280.degree. C. Further, it is preferably at most 350.degree. C.,
particularly preferably at most 320.degree. C. If the molding
temperature is too low, the melt viscosity tends to be high, the
fluidity tends to be decreased, the moldability may be decreased,
the effect of improving the surface hardness may be decreased, and
the surface hardness of the obtainable resin composition may be
decreased. If the molding temperature is too high, the
polycarbonate resin will be colored, whereby the color of the
polycarbonate resin composition is also deteriorated in some cases,
such being unfavorable.
<Method for Producing Injection-Molded Article>
[0207] To produce an injection-molded article from the
polycarbonate resin composition of the present invention, a
conventional injection molding machine is used.
[0208] When an injection molding machine or the like is used, the
mold temperature is preferably a temperature lower than Tg(b), more
preferably a temperature lower than Tg(a). Usually, it is
preferably at most 150.degree. C., more preferably at most
120.degree. C., most preferably at most 100.degree. C. Further, it
is preferably at least 30.degree. C., particularly preferably at
least 50.degree. C. If the mold temperature is too high, the
cooling time at the time of molding is required to be long, whereby
the cycle of production of the molded article tends to be long,
thus decreasing the productivity in some cases. If the mold
temperature is too low, the melt viscosity of the resin composition
tends to be too high, whereby no uniform molded article may be
obtained, and problems may arise such that the molded article
surface is non-uniform, such being unfavorable.
<Method for Producing Extruded Article>
[0209] To produce an extruded article from the polycarbonate resin
composition of the present invention, a conventional extruder is
used. The extruder is usually provided with a T-die, a round die or
the like, and extruded articles of various shapes can be obtained.
The shape of the obtained extruded article may, for example, be a
sheet, film, plate, tube or pipe shape. Among them, a sheet or a
film is preferred.
[0210] In order to improve the adhesion, coating properties,
printing properties and the like of the extruded article of the
polycarbonate resin composition of the present invention, a hard
coating layer may be laminated on both sides or one side of the
extruded article, a weather resistance and/or scratch resistance
improving film may be heat-laminated on both sides or one side of
the extruded article, or embossing or translucent or opaque
treatment may be applied to the surface.
[0211] Further, when injection molding or extrusion is carried out,
a pigment, a dye, a mold release agent, a thermal stabilizer or the
like may properly be added within a range not to impair the objects
of the present invention.
[0212] The above-mentioned molded article may be used in various
fields of buildings, vehicles, electric/electronic devices,
machines and others.
<Flame Retardancy of Molded Article of Polycarbonate
Resin>
[0213] A molded article of polycarbonate resin is prepared by using
the polycarbonate resin composition to which this embodiment is
applicable as described above. The method of molding the molded
article of polycarbonate resin is not particularly limited, and for
example, a molding method using a conventional molding machine such
as an injection molding machine may be mentioned. The molded
article of polycarbonate resin to which this embodiment is
applicable has a decrease in the surface hardness and the
transparency suppressed and has favorable flame retardancy, as
compared with a case of using, for example, a polycarbonate resin
obtainable by using e.g. bisphenol A having no substituent on the
phenyl ring as a monomer.
[0214] Specifically, the molded article of polycarbonate resin to
which this embodiment is applicable, with respect to the flame
retardancy, preferably satisfies the classification V-0 in a
flammability test of UL94 with respect to a test specimen having a
thickness of at most 2 mm. With respect to the transparency, the
haze is preferably at most 1.0 with respect to a test specimen
having a thickness of 3 mm in accordance with JIS K7136.
EXAMPLES
[0215] Now, the present invention will be described in further
detail with reference to Examples. However, it should be understood
that the present invention is not limited to the following
Examples.
[0216] Physical properties of polycarbonate resins and
polycarbonate resin compositions used in Examples were evaluated by
the following methods.
(1) Pencil Hardness of Molded Article
[0217] Using an injection molding machine J50E2 (manufactured by
Japan Steel Works, Ltd.), a plate (molded article) of a
polycarbonate resin or a plate (molded article) of a polycarbonate
resin composition of 60 mm.times.60 mm.times.3 mm in thickness was
molded by injection-molding under conditions of a barrel
temperature of 280.degree. C. and a mold temperature of 90.degree.
C. With respect to each molded article, in accordance with ISO
15184 using a pencil hardness tester (manufactured by Toyo Seiki
Seisaku-sho, Ltd.), the pencil hardness measured at a load of 750 g
was obtained.
(2) Melt Viscosity
[0218] It was measured with respect to a polycarbonate resin or a
polycarbonate resin composition dried at 120.degree. C. for 5 hours
by using a capillary rheometer "Capirograph 1C" (manufactured by
Toyo Seiki Seisaku-sho, Ltd.) equipped with a die of 1 mm in
diameter.times.30 mm at 280.degree. C. at a shear rate of 122
(sec.sup.-1). If this melt viscosity is too high, the fluidity
tends to be low, and the moldability will be deteriorated, and
accordingly it is required to be within an appropriate range.
(3) Intrinsic Viscosity [.eta.]
[0219] A polycarbonate resin or a polycarbonate resin composition
was dissolved in methylene chloride (concentration: 6.0 g/L
(liter)) to form a solution. Then, with respect to this solution,
the intrinsic viscosity was measured by an Ubbelohde viscosity tube
at a temperature of 20.degree. C.
(4) Glass Transition Temperature (Tg)
[0220] Using a differential scanning calorimeter DSC6220
(manufactured by Seiko Instruments Inc.), about 10 mg of a
polycarbonate resin sample was heated at a heating rate of
20.degree. C./min and the calorie is measured, and in accordance
with JIS K7121, an extrapolated glass transition starting
temperature which is a temperature at the intersection of a line
obtained by extending the base line on the low temperature side to
the high temperature side and a tangent drawn at a point where the
gradient of a curve of the stepwise change portion of glass
transition was maximum, was obtained. This extrapolated glass
transition temperature was regarded as the glass transition
temperature (Tg).
(5) Viscosity Average Molecular Weight (Mv)
[0221] A polycarbonate resin was dissolved in methylene chloride
(concentration: 6.0 g/L), the specific viscosity (.eta.sp) at
20.degree. C. was measured by using an Ubbelohde viscosity tube,
and the viscosity average molecular weight (Mv) was calculated in
accordance with the following formula.
.eta.sp/C=[.eta.](1+0.28.eta.sp)
[.eta.]=1.23.times.10.sup.-4Mv.sup.0.83
(6) Yellowness Index (YI) of Polycarbonate Resin or Polycarbonate
Resin Composition
[0222] Using the molded article molded in the above (1), the
yellowness index (YI) was measured by a spectral colorimeter
CM-3700d (manufactured by KONICA MINOLTA HOLDINGS, INC.). The
smaller the value, the brighter the color and the better the
transparency.
(7) Charpy Impact Strength of Polycarbonate Resin or Polycarbonate
Resin Composition
[0223] Using an injection molding machine J50E2 (manufactured by
Japan Steel Works, Ltd.), a polycarbonate resin or a polycarbonate
resin composition was molded to obtain a molded specimen under
conditions of a barrel temperature of 280.degree. C. and a mold
temperature of 90.degree. C. Using this molded specimen, in
accordance with JIS K7111, the impact strength was measured with a
notch of 0.25 mmR.
(8) Pencil Hardness of Extruded Article
[0224] A polycarbonate resin or a polycarbonate resin composition
having a thickness of 240 .mu.m and a width of 140.+-.5 mm was
extruded into a sheet (extruded article) by using a 25 mm.phi.
single screw extruder (manufactured by ISUZU KAKOKI K.K.) under
conditions of a barrel temperature of 280.degree. C. and a roll
temperature of 90.degree. C. With respect to this extruded article,
in accordance with ISO 15184, using a pencil hardness tester
(manufactured by Toyo Seiki Seisaku-sho, Ltd.), the pencil hardness
measured at a load of 750 g was obtained.
(9) Yellowness Index (YI) of Extruded Article
[0225] With respect to the extruded article molded in the above
(7), the yellowness index (YI) was measured by a spectral
colorimeter CM-3700d (manufactured by KONICA MINOLTA HOLDINGS,
INC.). The smaller the value, the brighter the color and the better
the transparency.
(10) Pencil Hardness of Polycarbonate Resin Cast Article
[0226] In a case where the molecular weight of the polycarbonate
resin is low and a molded article for evaluation of the pencil
hardness cannot be molded by the above-described method (1), an
evaluation sample was prepared as follows.
[0227] 100 g of a polycarbonate resin was added in a glass vessel
equipped with a stirring blade, followed by replacement with
nitrogen, and the pressure in the glass vessel was maintained at
101.3 kPa (760 Torr) by the absolute pressure. The glass vessel was
immersed in an oil bath heated at 280.degree. C. to melt the
polycarbonate resin. After the polycarbonate resin was uniformly
melted, the molten polycarbonate resin was taken out from the glass
vessel into a stainless steel vat in a thickness of about 3 mm and
cooled to room temperature. With respect to the cooled
polycarbonate resin, in accordance with ISO 15184, using a pencil
hardness tester (manufactured by Toyo Seiki Seisaku-sho, Ltd.), the
pencil hardness at a load of 750 g was measured.
(11) Content [S] of Structural Units (a) on the Surface of Molded
Article of Polycarbonate Resin.
[0228] A polycarbonate resin or a polycarbonate resin composition
was molded into a molded article of polycarbonate resin of 60
mm.times.60 mm.times.3 mm in thickness by an injection molding
machine J50E2 (manufactured by Japan Steel Works, Ltd.) under
conditions of a barrel temperature of 280.degree. C. and a mold
temperature of 90.degree. C. Then, the molded article of
polycarbonate resin was immersed in methylene chloride (about 400
g) at room temperature (25.degree. C.). Five seconds after the
start of immersion, the molded article of polycarbonate resin was
taken out from methylene chloride to obtain a methylene chloride
solution. By means of an evaporator, methylene chloride was removed
under reduced pressure from the methylene chloride solution to
obtain a residue. The residue was dissolved in deuterochloroform,
and the solution was subjected to measurement by .sup.1H-NMR
method. From the signal intensity of structural units (a) and
signal intensities of other structural units in the obtained
.sup.1H-NMR spectrum, the content [S] (wt %) of the structural
units (a) on the surface of the molded article of polycarbonate
resin was calculated.
(12) Content [T] of Structural Units (a) in the Entire Molded
Article of Polycarbonate Resin
[0229] In the same manner as the above (6), a molded article of
polycarbonate resin of 60 mm.times.60 mm.times.3 mm in thickness
was molded. Then, the molded article of polycarbonate resin was
immersed in methylene chloride (about 400 g) at room temperature
(25.degree. C.) and was completely dissolved, to obtain a methylene
chloride solution. About 50 g of the methylene chloride solution
was taken, methylene chloride was removed under reduced pressure by
means of an evaporator to obtain a residue. The residue was
dissolved in deuterochloroform, and the solution was subjected to
measurement by .sup.1H-NMR method. From the signal intensity of
structural units (a) and the signal intensities of other structural
units in the obtained .sup.1H-NMR spectrum, the content [T] (wt %)
of the structural units (a) in the entire molded article was
calculated.
[0230] The polycarbonate resins used in Examples are shown
below.
A. Polycarbonate Resin:
(1) Polycarbonate Resin (a):
Reference Example 1
Preparation of PC(a1)
[0231] To 37.6 kg (about 147 mol) of
2,2-bis(4-hydroxy-3-methylphenyl)propane (hereinafter sometimes
referred to as "BPC") (manufactured by HONSHU CHEMICAL INDUSTRY
CO., LTD.) and 32.2 kg (about 150 mol) of diphenyl carbonate (DPC),
an aqueous solution of cesium carbonate was added so that cesium
carbonate would be 2 .mu.mol per 1 mol of BPC to prepare a mixture.
Then, the mixture was charged into a first reactor having an
internal volume of 200 L equipped with a stirring machine, a heat
medium jacket, a vacuum pump and a reflux condenser.
[0232] Then, an operation of reducing the pressure in the first
reactor to 1.33 kPa (10 Torr) and then recovering it to the
atmospheric pressure by nitrogen was repeatedly carried out five
times, and then the interior in the first reactor was replaced with
nitrogen. After replacement with nitrogen, a heat medium at a
temperature of 230.degree. C. was passed through the heat medium
jacket to gradually increase the internal temperature in the first
reactor thereby to dissolve the mixture. Then, the stirring machine
was rotated at 300 rpm, and the temperature in the heat medium
jacket was controlled to keep the internal temperature of the first
reactor at 220.degree. C. Then, while phenol formed as a by-product
by an oligomerization reaction of BPC and DPC conducted in the
interior of the first reactor was distilled off, the pressure in
the first reactor was reduced from 101.3 kPa (760 Torr) to 13.3 kPa
(100 Torr) by the absolute pressure over a period of 40
minutes.
[0233] Then, the pressure in the first reactor was maintained at
13.3 kPa, and while phenol was further distilled off, an ester
exchange reaction was carried out for 80 minutes. Then, the
polycarbonate resin was withdrawn from the bottom of the tank.
[0234] The obtained polycarbonate resin (PC(a1) had a viscosity
average molecular weight of 1,900, and a glass transition
temperature (Tg) of at most 100.degree. C.
Reference Example 2
Preparation of PC(a2)
[0235] In the same manner as in Reference Example 1, an ester
exchange reaction in the first reactor was carried out for 80
minutes. Then, the pressure in the system was recovered to 101.3
kPa by the absolute pressure with nitrogen, and then the pressure
was elevated to 0.2 MPa by the gauge pressure, and by means of a
transfer pipe preliminarily heated to at least 200.degree. C., the
oligomer in the first reactor was pumped to a second reactor. The
second reactor had an internal volume of 200 L, was equipped with a
stirring machine, a heat medium jacket, a vacuum pump and a reflux
condenser, and had the internal pressure and the internal
temperature controlled to the atmospheric pressure and 240.degree.
C.
[0236] Then, the oligomer pumped to the second reactor was stirred
at 38 rpm, the internal temperature was raised by the heat medium
jacket, and the pressure in the second reactor was reduced from
101.3 kPa to 13.3 kPa by the absolute pressure over a period of 40
minutes. Then, the temperature-raising was continued, and the
internal pressure was reduced from 13.3 kPa to 399 Pa (3 Torr) by
the absolute pressure further over a period of 40 minutes, and
distilled phenol was removed out of the system. Further, the
temperature raising was continued, and after the absolute pressure
in the second reactor reached 70 Pa (about 0.5 Torr), the pressure
was maintained at 70 Pa, and a polycondensation reaction was
carried out. The final internal temperature in the second reactor
was 285.degree. C. When the stirring machine of the second reactor
achieved a preliminarily described predetermined stirring power,
the polycondensation reaction was completed.
[0237] The obtained polycarbonate resin (PC(a2) had a viscosity
average molecular weight of 6,700 and a glass transition
temperature (Tg) of 101.degree. C.
Reference Examples 3 and 4
Preparation of PC(a3) and PC(a4)
[0238] A reaction was carried out in accordance with Reference
Example 2 except that the preliminarily determined stirring power
of the stirring machine of the second reactor at the time of
completion was changed. Then, the pressure in the second reactor
was recovered to 101.3 kPa by the absolute pressure with nitrogen,
and then the pressure was elevated to 0.2 MPa by the gauge
pressure, the polycarbonate resin was withdrawn from the bottom of
the second reactor in the form of strands, which were pelletized by
using a rotary cutter while cooling in a water tank.
[0239] That is, by changing the preliminarily determined stirring
power of the stirring machine of the second reactor at the time of
completion, a polycarbonate resin (PC(a3)) and a polycarbonate
resin (PC(a4)) were respectively obtained. The viscosity average
molecular weight, the glass transition temperature (Tg) and the
pencil hardness are as shown in Table 1.
Reference Example 5
Preparation of PC(a5)
[0240] The same operation as in Reference Example 3 was carried out
except that 43.5 kg of 1,1-bis(4-hydroxy-3-methylphenyl)cyclohexane
(hereinafter sometimes referred to as "Bis-OCZ") (manufactured by
HONSHU CHEMICAL INDUSTRY CO., LTD.) was used instead of BPC as the
material dihydroxy compound, and the aqueous solution of cesium
carbonate was added so that cesium carbonate would be 5 .mu.mol per
1 mol of Bis-OCZ. Of the obtained polycarbonate resin (PC(a5)), the
viscosity average molecular weight was 10,200, the glass transition
temperature (Tg) was 132.degree. C., and the pencil hardness was
3H.
Reference Example 6
Preparation of PC(a6)
[0241] 100 Parts by weight of Bis-OCZ (manufactured by HONSHU
CHEMICAL INDUSTRY CO., LTD.), 272.1 parts by weight of a 25 wt %
sodium hydroxide (NaOH) aqueous solution and 411.3 parts by weight
of water, in the presence of 0.339 part by weight of hydrosulfite,
were dissolved at 60.degree. C. and then cooled to room temperature
to obtain a Bis-OCZ aqueous solution. This Bis-OCZ aqueous solution
in a rate of 8.87 kg/hour (the amount per one hour, the same
applies hereinafter) and methylene chloride in a rate of 4.37
kg/hour were introduced into a 1.8 L glass first reactor equipped
with a reflux condenser, a stirring machine and a coolant jacket,
and were brought into contact with phosgene at room temperature
separately supplied thereto in a rate of 0.775 kg/hour. The
reaction temperature at this time reached 38.degree. C. Then, the
reaction liquid/reaction gas mixture was introduced into a
subsequent second reactor (1.8 L) having the same shape as the
first reactor by means of an overflow tube attached to the reactor
and reacted. Into the second reactor, separately, p-t-butylphenol
(16 wt % methylene chloride solution) as a molecular weight
adjusting agent was introduced in a rate of 0.037 kg/hour. Then,
the reaction liquid/reaction gas mixture was introduced into an
oligomerization tank (4.5 L) having the same shape as the first
reactor through an overflow tube attached to the second reactor.
Into the oligomerization tank, separately, a 2 wt % trimethylamine
aqueous solution as a catalyst was introduced in a rate of 0.016
kg/hour (0.00083 mol per 1 mol of Bis-OCZ). Then, the oligomerized
emulsion thus obtained was further introduced into a separation
tank (settler) having an internal volume of 5.4 L to separate an
aqueous phase and an oil phase, thereby to obtain a methylene
chloride solution of the oligomer.
[0242] 2.44 kg of the above methylene chloride solution of the
oligomer was charged into a reaction tank having an internal volume
of 6.8 L equipped with a paddle blade, and 2.60 kg of methylene
chloride for dilution was added, and further 0.245 kg of a 25 wt %
sodium hydroxide aqueous solution, 0.953 kg of water and 8.39 g of
a 2 wt % triethylamine aqueous solution were added, followed by
stirring at 10.degree. C. to carry out a polycondensation reaction
for 180 minutes.
[0243] 3.12 kg of the polycondensation reaction liquid was charged
into a reaction tank having an internal volume of 5.4 L equipped
with a paddle blade, and 2.54 kg of methylene chloride and 0.575 kg
of water were added, followed by stirring for 15 minutes, and then
stirring was stopped, and an aqueous phase and an organic phase
were separated. To the separated organic phase, 1.16 kg of 0.1 N
hydrochloric acid was added, followed by stirring for 15 minutes,
to extract triethylamine and an alkali component remaining in a
small amount, and then stirring was stopped, and an aqueous phase
and an organic phase were separated. Further, to the separated
organic phase, 1.16 kg of pure water was added, followed by
stirring for 15 minutes, and then stirring was stopped, and an
aqueous phase and an organic phase were separated. This operation
was repeated three times. The obtained polycarbonate solution was
transferred (fed) into warm water of from 60 to 75.degree. C. to
powder the polycarbonate resin, followed by drying to obtain a
powdery polycarbonate resin (PC(a6)). The viscosity average
molecular weight, the glass transition temperature (Tg) and the
pencil hardness are as shown in Table 1.
Reference Example 2-1
PC(a2-1)
[0244] 100 Parts by weight of Bis-OCZ as the material dihydroxy
compound, 272.1 parts by weight of a 25 wt % sodium hydroxide
(NaOH) aqueous solution and 411.3 parts by weight of water, in the
presence of 0.339 part by weight of hydrosulfite, were dissolved at
60.degree. C. and then cooled to room temperature to obtain a
Bis-OCZ aqueous solution. This Bis-OCZ aqueous solution in a rate
of 8.87 kg/hour and methylene chloride in a rate of 4.37 kg/hour
were introduced into a 1.8 L glass first reactor equipped with a
reflux condenser, a stirring machine and a coolant jacket, and
brought into contact with phosgene at room temperature separately
supplied thereto in a rate of 0.775 kg/hour. The reaction
temperature at this time reached 38.degree. C. Then, the reaction
liquid/reaction gas mixture was introduced into a subsequent second
reactor (1.8 L) having the same shape as the first reactor through
an overflow tube attached to the reactor, and reacted. To the
second reactor, separately, p-t-butylphenol (16 wt % methylene
chloride solution) as a molecular weight adjusting agent was
introduced in a rate of 0.037 kg/hour. Then, the reaction
liquid/reaction gas mixture was introduced into an oligomerization
tank (4.5 L) having the same shape as the first reactor through an
overflow tube attached to the second reactor. To the
oligomerization tank, separately, a 2 wt % trimethylamine aqueous
solution as a catalyst was introduced in a rate of 0.016 kg/hour
(0.00083 mol per 1 mol of Bis-OCZ). Then, the oligomerized emulsion
thus obtained was further introduced into a separation tank
(settler) having an internal volume of 5.4 L to separate an aqueous
phase and an oil phase, thereby to obtain a methylene chloride
solution of the oligomer.
[0245] 2.44 kg of the above methylene chloride solution of the
oligomer was charged into a reaction tank having an internal volume
of 6.8 L equipped with a paddle blade, and 2.60 kg of methylene
chloride for dilution was added, and further 0.245 kg of a 25 wt %
sodium hydroxide aqueous solution, 0.953 kg of water, 8.39 g of a 2
wt % triethylamine aqueous solution and 25.8 g of p-t-butylphenol
(16 wt % methylene chloride solution) as a molecular weight
adjusting agent were added, followed by stirring at 10.degree. C.
to carry out a polycondensation reaction for 180 minutes.
[0246] 3.12 kg of the above polycondensation reaction liquid was
charged into a reaction tank having an internal volume of 5.4 L
equipped with a paddle blade, and 2.54 kg of methylene chloride and
0.575 kg of water were added, followed by stirring for 15 minutes,
and then stirring was stopped to separate an aqueous phase and an
organic phase. To the separated organic phase, 1.16 kg of 0.1 N
hydrochloric acid was added, followed by stirring for 15 minutes,
to extract triethylamine and an alkali component remaining in a
small amount, and then stirring was stopped to separate an aqueous
phase and an organic phase. Further, to the separated organic
phase, 1.16 kg of pure water was added, followed by stirring for 15
minutes, and then stirring was stopped and an aqueous phase and an
organic phase were separated. This operation was repeated three
times. The obtained polycarbonate solution was transferred to warm
water of from 60 to 75.degree. C., to powder the polycarbonate
resin, followed by drying to obtain a powdery polycarbonate resin.
The intrinsic viscosity was 0.23, and the pencil hardness was
3H.
Reference Example 2-2
Preparation of PC(a2-2)
[0247] To 43.5 kg (about 147 mol) of Bis-OCZ (manufactured by
HONSHU CHEMICAL INDUSTRY CO., LTD.) as the material dihydroxy
carbonate and 32.2 kg (about 150 mol) of diphenyl carbonate (DPC),
an aqueous solution of cesium carbonate was added so that cesium
carbonate would be 5 .mu.mol per 1 mol of the dihydroxy compound to
prepare a mixture. Then, the mixture was charged into a first
reactor having an internal capacity of 200 L equipped with a
stirring machine, a heat medium jacket, a vacuum pump and a reflux
condenser.
[0248] Then, an operation of reducing the pressure in the first
reactor to 1.33 kPa (10 Torr) and then recovering it to the
atmospheric pressure with nitrogen was repeatedly carried out five
times, and the interior in the first reactor was replaced with
nitrogen. After replacement with nitrogen, a heat medium at a
temperature of 230.degree. C. was passed through the heat medium
jacket to gradually increase the internal temperature in the first
reactor to dissolve the mixture. Then, the stirring machine was
rotated at 300 rpm, and the temperature in the heat medium jacket
was controlled to maintain the internal temperature of the first
reactor at 220.degree. C. Then, while phenol formed as a by-product
by an oligomerization reaction of Bis-OCZ and DPC carried out in
the interior of the first reactor was distilled off, the pressure
in the first reactor was reduced from 101.3 kPa (760 Torr) to 13.3
kPa (100 Torr) by the absolute pressure over a period of 40
minutes.
[0249] Then, the pressure in the first reactor was maintained at
13.3 kPa, and while phenol was further distilled off, an ester
exchange reaction was carried out for 80 minutes. Then, the
polycarbonate resin was withdrawn from the bottom of the tank.
[0250] The obtained polycarbonate resin had an intrinsic viscosity
of 0.07.
Reference Example 2-3
Preparation of PC(a2-3)
[0251] In the same manner as in Reference Example 2-2, an ester
exchange reaction in the first reactor was carried out for 80
minutes. Then, the pressure in the system was recovered to 101.3
kPa by the absolute pressure with nitrogen, and then the pressure
was elevated to 0.2 MPa by the gauge pressure, and the oligomer in
the first reactor was pumped to a second reactor by means of a
transfer pipe preliminarily heated to at least 200.degree. C. The
second reactor had an internal volume of 200 L, was provided with a
stirring machine, a heat medium jacket, a vacuum pump and a reflux
condenser, and had the internal pressure and the internal
temperature controlled to be the atmospheric pressure and
240.degree. C.
[0252] Then, the oligomer pumped to the second reactor was stirred
at 38 rpm, the internal temperature was raised by the heat medium
jacket, and the pressure in the second reactor was reduced from
101.3 kPa to 13.3 kPa by the absolute pressure over a period of 40
minutes. Then, the temperature raising was continued, and the
internal pressure was reduced from 13.3 kPa to 399 Pa (3 Torr) by
the absolute pressure further over a period of 40 minutes, and the
distilled phenol was removed out of the system. Further, the
temperature raising was continued, and after the absolute pressure
in the second reactor reached 70 Pa (about 0.5 Torr), a pressure of
70 Pa was maintained, and a polycondensation reaction was carried
out. The final internal temperature in the second reactor was
285.degree. C. When the stirring machine of the second reactor
achieved a preliminarily determined stirring power, the
polycondensation reaction was completed.
[0253] The obtained polycarbonate resin had an intrinsic viscosity
of 0.26 and a pencil hardness of 3H.
Reference Example 2-4
Preparation of PC(a2-4)
[0254] A polycarbonate resin was obtained in the same manner as in
Reference Example 2-3 except that to 37.6 kg (about 147 mol) of BPC
(manufactured by HONSHU CHEMICAL INDUSTRY CO., LTD.) as the
material dihydroxy compound and 32.2 kg (about 150 mol) of diphenyl
carbonate (DPC), an aqueous solution of cesium carbonate was added
in an amount of 2 .mu.mol per 1 mol of the dihydroxy compound to
prepare a mixture. The obtained polycarbonate resin had an
intrinsic viscosity of 0.06.
Reference Example 2-5
Preparation of PC(a2-5)
[0255] 360 Parts by weight of BPC (manufactured by HONSHU CHEMICAL
INDUSTRY CO., LTD.), 585.1 parts by weight of a 25 wt % sodium
hydroxide (NaOH) aqueous solution and 1,721.5 parts by weight of
water, in the presence of 0.41 part by weight of hydrosulfite, were
dissolved at 40.degree. C. and then cooled to 20.degree. C. to
obtain a BPC aqueous solution. This BPC aqueous solution in a rate
of 8.87 kg/hour and methylene chloride in a rate of 4.50 kg/hour
were introduced into a 1.8 L glass first reactor equipped with a
reflux condenser, a stirring machine and a coolant jacket, and
brought into contact with phosgene at room temperature separately
supplied thereto in a rate of 0.672 kg/hour. The reaction
temperature at this time reached 35.degree. C. Then, the reaction
liquid/reaction gas mixture was introduced into a subsequent second
reactor (1.8 L) having the same shape as the first reactor through
an overflow tube attached to the reactor, and reacted. To the
second reactor, separately, p-t-butylphenol (8 wt % methylene
chloride solution) as a molecular weight adjusting agent was
introduced in a rate of 0.097 kg/hour. Then, the reaction
liquid/reaction gas mixture was introduced into an oligomerization
tank (4.5 L) having the same shape as the first reactor through an
overflow tube attached to the second reactor. To the
oligomerization tank, separately, a 2 wt % trimethylamine aqueous
solution as a catalyst was introduced in a rate of 0.020 kg/hour.
Then, the oligomerized emulsion thus obtained was further
introduced into a separation tank (settler) having an internal
volume of 5.4 L to separate an aqueous phase and an oil phase,
thereby to obtain a methylene chloride solution of the
oligomer.
[0256] 2.60 kg of the above methylene chloride solution of the
oligomer was charged into a reaction tank having an internal volume
of 6.8 L equipped with a paddle blade, and 2.44 kg of methylene
chloride for dilution was added, and further 0.278 kg of a 25 wt %
sodium hydroxide aqueous solution, 0.927 kg of water, 8.37 g of a 2
wt % triethylamine aqueous solution and 25.8 g of p-t-butylphenol
(8 wt % methylene chloride solution) were added, followed by
stirring at 10.degree. C. to carry out a polycondensation reaction
for 180 minutes.
[0257] 3.12 kg of the above polycondensation reaction liquid was
charged into a reaction tank having an internal volume of 5.4 L
equipped with a paddle blade, and 2.54 kg of methylene chloride and
0.575 kg of water were added, followed by stirring for 15 minutes,
and then stirring was stopped to separate an aqueous phase and an
organic phase. To the separated organic phase, 1.16 kg of 0.1 N
hydrochloric acid was added, followed by stirring for 15 minutes,
to extract triethylamine and an alkali component remaining in a
small amount, and then stirring was stopped to separate an aqueous
phase and an organic phase. Further, to the separated organic
phase, 1.16 kg of pure water was added, followed by stirring for 15
minutes, and then stirring was stopped and an aqueous phase and an
organic phase were separated. This operation was repeated three
times. The obtained polycarbonate solution was transferred to warm
water of from 60 to 75.degree. C., to powder the polycarbonate
resin, followed by drying to obtain a powdery polycarbonate resin.
The obtained polycarbonate resin had an intrinsic viscosity of 0.25
and a pencil hardness of 2H.
Reference Example 2-6
Preparation of PC(a2-6)
[0258] In the same manner as in Reference Example 2-4, an ester
exchange reaction in the first reactor was carried out for 80
minutes. Then, the pressure in the system was recovered to 101.3
kPa by the absolute pressure with nitrogen, and then the pressure
was elevated to 0.2 MPa by the gauge pressure, and the oligomer in
the first reactor was pumped to a second reactor by means of a
transfer pipe preliminarily heated to at least 200.degree. C. The
second reactor had an internal volume of 200 L, was provided with a
stirring machine, a heat medium jacket, a vacuum pump and a reflux
condenser, and had the internal pressure and the internal
temperature controlled to be the atmospheric pressure and
240.degree. C.
[0259] Then, the oligomer pumped to the second reactor was stirred
at 38 rpm, the internal temperature was raised by the heat medium
jacket, and the pressure in the second reactor was reduced from
101.3 kPa to 13.3 kPa by the absolute pressure over a period of 40
minutes. Then, the temperature raising was continued, and the
internal pressure was reduced from 13.3 kPa to 399 Pa (3 Torr) by
the absolute pressure further over a period of 40 minutes, and the
distilled phenol was removed out of the system. Further, the
temperature raising was continued, and after the absolute pressure
in the second reactor reached 70 Pa (about 0.5 Torr), a pressure of
70 Pa was maintained, and a polycondensation reaction was carried
out. The final internal temperature in the second reactor was
285.degree. C. When the stirring machine of the second reactor
achieved a preliminarily determined stirring power, the
polycondensation reaction was completed. The obtained polycarbonate
resin had an intrinsic viscosity of 0.18 and a pencil hardness of
2H.
Reference Example 2-7
Preparation of PC(a2-7)
[0260] A reaction was carried out in accordance with Reference
Example 2-6 except that the preliminarily determined stirring power
of the stirring machine of the second reactor at the time of
completion was changed. Then, the pressure in the second reactor
was recovered to 101.3 kPa by the absolute pressure with nitrogen,
and the pressure was elevated to 0.2 MPa by the gauge pressure, and
the polycarbonate resin was withdrawn from the bottom of the second
reactor in the form of strands, which were pelletized by using a
rotary cutter while cooling in a water tank. The obtained
polycarbonate resin had an intrinsic viscosity of 0.69 and a pencil
hardness of 2H.
Reference Example 2-8
Preparation of PC(a2-8)
[0261] A polycarbonate resin was obtained in the same manner as in
Reference Example 2-5 except that when the methylene chloride
solution was charged into the reaction tank having an internal
volume of 6.8 L equipped with a paddle blade, p-t-butylphenol as a
molecular weight adjusting agent was not introduced. The intrinsic
viscosity was 0.97, and the pencil hardness was 2H.
Reference Example 2-9
Preparation of PC(a2-9)
[0262] A polycarbonate resin was obtained in the same manner as in
Reference Example 2-1 except that when the methylene chloride
solution was charged into the reaction tank having an internal
volume of 6.8 L equipped with a paddle blade, no molecular weight
adjusting agent was added. The intrinsic viscosity was 0.98, and
the pencil hardness was 3H.
Reference Example 2-10
Preparation of PC(a2-10): Preparation of CDOBC/BPA (50/50 wt %)
Copolymer (Melt Method)
[0263] The same operation as in Reference Example 2-7 was carried
out except that 20.62 kg (about 90 mol) of BPA and 20.62 kg (about
54 mol) of CDOBC (manufactured by Taoka Chemical Co., Ltd.) were
used as the dihydroxy compounds, and the aqueous solution of cesium
carbonate was added so that cesium carbonate would be 1 .mu.mol per
1 mol of the dihydroxy compounds to prepare a mixture. The obtained
polycarbonate resin had an intrinsic viscosity of 0.29 and a pencil
hardness of H.
Reference Example 3-1
Preparation of PC(a3-1) (BPC Homopolymer, Melt Method)
[0264] To 37.60 kg (about 147 mol) of BPC (manufactured by HONSHU
CHEMICAL INDUSTRY CO., LTD.) as the material dihydroxy compound and
32.20 kg (about 150 mol) of diphenyl carbonate (DPC), an aqueous
solution of cesium carbonate was added so that cesium carbonate
would be 2 .mu.mol per 1 mol of the dihydroxy compound to prepare a
mixture. The mixture was charged into a first reactor having an
internal volume of 200 L equipped with a stirring machine, a heat
medium jacket, a vacuum pump and a reflux condenser.
[0265] Then, an operation of reducing the pressure in the first
reactor to 1.33 kPa (10 Torr) and then recovering it to the
atmospheric pressure with nitrogen was repeatedly carried out five
times, and the interior in the first reactor was replaced with
nitrogen. After replacement with nitrogen, a heat medium at a
temperature of 230.degree. C. was passed through the heat medium
jacket to gradually increase the internal temperature in the first
reactor to dissolve the mixture. Then, the stirring machine was
rotated at 300 rpm, and the temperature in the heat medium jacket
was controlled to maintain the internal temperature of the first
reactor at 220.degree. C. Then, while phenol formed as a by-product
by an oligomerization reaction of BPC and DPC carried out in the
interior of the first reactor was distilled off, the pressure in
the first reactor was reduced from 101.3 kPa (760 Torr) to 13.3 kPa
(100 Torr) over a period of 40 minutes.
[0266] Then, the pressure in the first reactor was maintained at
13.3 kPa, and while phenol was further distilled off, an ester
exchange reaction was carried out for 80 minutes.
[0267] Then, the pressure in the system was recovered to 101.3 kPa
by the absolute pressure with nitrogen, and then the pressure was
elevated to 0.2 MPa by the gauge pressure, and the oligomer in the
first reactor was pumped to a second reactor by means of a transfer
pipe preliminarily heated to at least 200.degree. C. The second
reactor had an internal volume of 200 L, was provided with a
stirring machine, a heat medium jacket, a vacuum pump and a reflux
condenser, and had the internal pressure and the internal
temperature controlled to be the atmospheric pressure and
240.degree. C.
[0268] Then, the oligomer pumped to the second reactor was stirred
at 38 rpm, the internal temperature was raised by the heat medium
jacket, and the pressure in the second reactor was reduced from
101.3 kPa to 13.3 kPa by the absolute pressure over a period of 40
minutes. Then, the temperature raising was continued, and the
internal pressure was reduced from 13.3 kPa to 399 Pa (3 Torr) by
the absolute pressure further over a period of 40 minutes, and the
distilled phenol was removed out of the system. Further, the
temperature raising was continued, and after the absolute pressure
in the second reactor reached 70 Pa (about 0.5 Torr), a pressure of
70 Pa was maintained, and a polycondensation reaction was carried
out. The final internal temperature in the second reactor was
285.degree. C. When the stirring machine of the second reactor
achieved a preliminarily determined stirring power, the
polycondensation reaction was completed.
[0269] Then, the pressure in the second reactor was recovered to
101.3 kPa by the absolute pressure with nitrogen, and then the
pressure was elevated to 0.2 MPa by the gauge pressure, and the
polycarbonate resin was withdrawn from the bottom of the second
reactor in the form of strands, which were pelletized by using a
rotary cutter while cooling in a water tank. The viscosity average
molecular weight of the obtained polycarbonate resin was
17,200.
[0270] The polycarbonate resin was evaluated in accordance with the
above items. The results are shown in Table 3-1.
Reference Example 3-2
Preparation of PC(a3-2) (BPC Homopolymer, Melt Method)
[0271] The same operation as in Reference Example 3-1 was carried
out except that the preliminarily determined stirring power of the
stirring machine of the second reactor was changed. The obtained
polycarbonate resin had a viscosity average molecular weight of
18,500.
[0272] The results of evaluation in the same manner as in Reference
Example 3-1 are shown in Table 3-1.
Reference Example 3-3
Preparation of PC(a3-3) (BPC Homopolymer, Melt Method)
[0273] The same operation as in Reference Example 3-1 was carried
out except that the preliminarily determined stirring power of the
stirring machine of the second reactor was changed. The obtained
polycarbonate resin had a viscosity average molecular weight of
30,300.
[0274] The results of evaluation in the same manner as in Reference
Example 3-1 are shown in Table 3-1.
Reference Example 3-4
Preparation of PC(a3-4) (Bis-OCZ Homopolymer, Melt Method)
[0275] The same operation as in Reference Example 3-1 was carried
out except that 43.48 kg of Bis-OCZ (manufactured by HONSHU
CHEMICAL INDUSTRY CO., LTD.) was used instead of BPC as the
material dihydroxy compound, and the aqueous solution of cesium
carbonate was added so that cesium carbonate would be 5 .mu.mol per
1 mol of the dihydroxy compound. The obtained polycarbonate resin
had a viscosity average molecular weight of 10,200.
[0276] The results of evaluation in the same manner as in Reference
Example 3-1 are shown in Table 3-1.
Reference Example 3-5
Preparation of PC(a3-5) (BPC/BPA (30/70 wt %) Copolymer, Melt
Method)
[0277] A polycarbonate resin was obtained in the same manner as in
Reference Example 3-1 except that 10.05 kg of BPC (manufactured by
HONSHU CHEMICAL INDUSTRY CO., LTD.) and 23.45 kg of BPA
(manufactured by Mitsubishi Chemical Corporation) were used instead
of BPC as the material dihydroxy compounds. The obtained
polycarbonate resin had a viscosity average molecular weight of
25,200.
[0278] The results of evaluation in the same manner as in Reference
Example 3-1 are shown in Table 3-1.
Reference Example 3-6
Preparation of PC(a3-6) (BPC/BPA (10/90 wt %) Copolymer, Melt
Method)
[0279] A polycarbonate resin was obtained in the same manner as in
Reference Example 3-1 except that 3.35 kg of BPC (manufactured by
HONSHU CHEMICAL INDUSTRY CO., LTD.) and 30.15 kg of BPA
(manufactured by Mitsubishi Chemical Corporation) were used as the
material dihydroxy compounds. The obtained polycarbonate resin had
a viscosity average molecular weight of 24,700.
[0280] The results of evaluation in the same manner as in Reference
Example 3-1 are shown in Table 3-1.
(2) Polycarbonate Resin (b)
Reference Example 7
Preparation of PC(b1) (BPA/BPC Copolymer)
[0281] A polycarbonate resin (PC(b1)) was obtained in the same
manner as in Reference Example 2 except that 30.5 kg of
(2,2-bis(4-hydroxyphenyl)propane (BPA) (manufactured by Mitsubishi
Chemical Corporation) and 3.4 kg of BPC (manufactured by HONSHU
CHEMICAL INDUSTRY CO., LTD.) were used instead of BPC as the
material dihydroxy compounds. The viscosity average molecular
weight, the glass transition temperature (Tg) and the pencil
hardness are as shown in Table 1.
Reference Example 8
Preparation of PC(b2) (BPA/BPC Copolymer)
[0282] A polycarbonate resin (PC(b2)) was obtained in the same
manner as in Reference Example 2 except that 24.2 kg of BPA
(manufactured by Mitsubishi Chemical Corporation) and 10.4 kg of
BPC (manufactured by HONSHU CHEMICAL INDUSTRY CO., LTD.) were used
instead of BPC as the material dihydroxy compounds. The viscosity
average molecular weight, the glass transition temperature (Tg) and
the pencil hardness are as shown in Table 1.
Reference Example 9
PC(b3)
[0283] As PC(b3), a commercially available polycarbonate resin
constituted only by structural units derived from BPA, formed by
the melt method, was used. It had a viscosity average molecular
weight of 20,600 and a melt viscosity of 9,010 poise. Further, it
had an intrinsic viscosity of 0.47 and a pencil hardness of 2B.
Reference Example 2-11
PC(b2-1) (M7027J (BPA Homopolymer) Manufactured by Mitsubishi
Engineering-Plastics Corporation)
[0284] As PC(b2-1), a commercially available polycarbonate resin
constituted only by structural units derived from BPA, formed by
the melt method, was used. It had a viscosity average molecular
weight of 25,600 and a melt viscosity of 22,120 poise. Further, it
had an intrinsic viscosity of 0.56 and a pencil hardness of 2B.
Reference Example 2-12
PC(b2-2) (BPA/BPC Copolymer (Melt Method))
[0285] A polycarbonate resin was obtained in the same manner as in
Reference Example 2-7 except that 27.4 kg of BPA (manufactured by
Mitsubishi Chemical Corporation) and 6.8 kg of BPC (manufactured by
HONSHU CHEMICAL INDUSTRY CO., LTD.) were used instead of BPC as the
material dihydroxy compounds. It had an intrinsic viscosity of 0.48
and a pencil hardness of HB.
Reference Example 3-7
PC(b3-1) (BPA Homopolymer, Melt Method)
[0286] As PC(b3-1), a commercially available polycarbonate resin
(M7022J manufactured by Mitsubishi Engineering-Plastics
Corporation) constituted only by structural units derived from BPA,
formed by the melt method, was used. The viscosity average
molecular weight of PC(b3-1) was 20,000.
[0287] The results of evaluation in the same manner as in Reference
Example 3-1 are shown in Table 3-1.
[0288] The glass transition point (Tg), the viscosity average
molecular weight (Mv) and the pencil hardness of the polycarbonate
resins (a) and (b) used as the materials of the polycarbonate resin
compositions in Examples and Comparative Examples are shown in
Table 1.
TABLE-US-00001 TABLE 1 PC resin Blend ratio (wt %) (abbreviated of
dihydroxy Pencil name) compound Tg (.degree. C.) Mv hardness PC(a1)
BPC(100) .ltoreq.100 1,900 PC(a2) BPC(100) 101 6,700 PC(a3)
BPC(100) 119 18,500 2H PC(a4) BPC(100) 122 33,000 2H PC(a5)
Bis-OCZ(100) 132 10,200 3H PC(a6) Bis-OCZ(100) 138 49,900 3H PC(b1)
BPA/BPC 144 21,700 B (90/10) PC(b2) BPA/BPC 138 20,300 F (70/30)
PC(b3) BPA(100) 145 20,600 2B
Examples 1 to 9 and Comparative Examples 1 to 5
[0289] Using the above polycarbonate resins, by a twin screw
extruder (LABOTEX 30HSS-32) manufactured by Japan Steel Works, Ltd.
having one vent port, the respective polycarbonate resin
compositions were prepared.
Example 1
[0290] As the polycarbonate resin (a) and the polycarbonate resin
(b), PC(a2) and PC(b3) in a ratio as identified in Table 2 were
melt-kneaded in the above twin screw extruder, extruded from the
outlet of the twin screw extruder in the form of strands,
solidified by cooling with water, and pelletized by a rotary cutter
to obtain a polycarbonate resin composition. On that occasion, the
barrel temperature of the twin screw extruder was 280.degree. C.,
and the polycarbonate resin temperature at the outlet of the twin
screw extruder was 300.degree. C. At the time of melt-kneading, the
vent port of the twin screw extruder was connected to a vacuum
pump, and the pressure at the vent port was controlled to be 500
Pa.
[0291] The polycarbonate resin composition was subjected to
evaluation with respect to the surface hardness, the glass
transition temperature (Tg), the melt viscosity and the Charpy
impact strength, in accordance with methods as described in the
above evaluation items. The results are shown in Table 2 together
with the amount of the polycarbonate resin used.
Examples 2 to 9
[0292] Polycarbonate resin compositions were obtained in the same
manner as in Example 1 except that two types of polycarbonate
resins as identified in Table 2 were employed.
[0293] The polycarbonate resin compositions were subjected to
evaluation with respect to the surface hardness, the glass
transition temperature (Tg), the melt viscosity and the Charpy
impact strength, in accordance with methods as described in the
above evaluation items. The results are shown in Table 2 together
with the amount of the polycarbonate resins used.
[0294] Further, the polycarbonate resin compositions in Examples 3
to 6 were molded into extruded articles (sheets) by the above
method, which were subjected to evaluation with respect to the
pencil hardness and the yellowness index (YI). The results are
shown in Table 2.
Example 10
[0295] As the polycarbonate resin (a) and the polycarbonate resin
(b), pellets of PC(a3) and pellets of PC(b3) were dry-blended in a
ratio as identified in Table 2 to obtain a polycarbonate resin
composition.
[0296] The polycarbonate resin composition was subjected to
evaluation with respect to the surface hardness, the melt viscosity
and the Charpy impact strength in accordance with methods as
described in the above evaluation items. The results are shown in
Table 2 together with the amount of the polycarbonate resin
used.
Comparative Examples 1 to 2
[0297] Polycarbonate resin compositions in Comparative Examples 1
and 2 were obtained in the same manner as in Example 1 except that
two types of polycarbonate resins as identified in Table 2 were
employed.
[0298] The polycarbonate resin compositions were subjected to
evaluation with respect to the surface hardness, the glass
transition temperature (Tg), the melt viscosity and the Charpy
impact strength in accordance with methods as described in the
above evaluation items. The results are shown in Table 2 together
with the amount of the polycarbonate resins used.
[0299] Further, the polycarbonate resin composition in Comparative
Example 1 was molded into an extruded article (sheet) by the above
method, which was subjected to evaluation with respect to the
pencil hardness and the yellowness index (YI). The results are
shown in Table 2.
Comparative Examples 3 to 5
[0300] The surface hardness, the glass transition temperature (Tg),
the melt viscosity and the Charpy impact strength of PC(b2) in
Comparative Example 3, PC(b1) in Comparative Example 4 and PC(b3)
in Comparative Example 5 by themselves were evaluated. The results
are shown in Table 2.
[0301] Further, the polycarbonate resin compositions in Comparative
Examples 3 to 5 were molded into extruded articles (sheets) by the
above method, which were subjected to evaluation with respect to
the pencil hardness and the yellowness index (YI). The results are
shown in Table 2.
TABLE-US-00002 TABLE 2 Ex. PC resin 1 2 3 4 5 6 7 8 PC(a) PC(a1) --
-- -- -- -- -- -- -- parts by weight PC(a2) 10 20 -- -- -- -- -- --
PC(a3) -- -- 10 20 30 -- -- -- PC(a4) -- -- -- -- -- 10 20 30
PC(a5) -- -- -- -- -- -- -- -- PC(a6) -- -- -- -- -- -- -- -- PC(b)
PC(b1) -- -- -- -- -- -- -- -- parts by weight PC(b2) -- -- -- --
-- -- -- -- PC(b3) 90 80 90 80 70 90 80 70 Mv (a)/Mv (b) 0.335
0.335 0.925 0.925 0.925 1.65 1.65 1.65 Pencil hardness of PC
composition HB F F F H HB F F Difference in pencil hardness between
2 3 3 3 4 2 3 3 PC composition and PC(b) Tg (.degree. C.) 138 134
142 139 136 143 140 138 Melt viscosity (poise) 5,747 3,506 7,846
6,915 5,978 9,417 10,340 11,140 Charpy impact strength (kJ/m.sup.2)
11 9 14 11 8 12 11 10 YI (--) 2.5 2.3 2.3 2.5 2.8 2.8 2.8 3.3
Pencil hardness of PC sheet -- -- F F H F -- -- Thickness (.mu.m)
of PC sheet -- -- 240 240 240 240 -- -- YI (--) of PC sheet -- --
0.86 0.86 0.87 0.87 -- -- Ex. Comp. Ex. PC resin 9 10 1 2 3 4 5
PC(a) PC(a1) -- -- 20 -- -- -- -- parts by weight PC(a2) -- -- --
-- -- -- -- PC(a3) -- 30 -- -- -- -- -- PC(a4) -- -- -- -- -- -- --
PC(a5) 10 -- -- -- -- -- -- PC(a6) -- -- -- 20 -- -- -- PC(b)
PC(b1) -- -- -- -- -- 100 -- parts by weight PC(b2) -- -- -- -- --
-- 100 PC(b3) 90 70 80 80 100 -- -- Mv (a)/Mv (b) 0.51 0.925 0.095
2.495 -- -- -- Pencil hardness of PC composition HB H F F 2B B F
Difference in pencil hardness between 2 4 3 3 0 0 0 PC composition
and PC(b) Tg (.degree. C.) 144 -- 122 143 145 144 138 Melt
viscosity (poise) 7,930 6,080 1,920 17,570 9,010 8,830 9,210 Charpy
impact strength (kJ/m.sup.2) 12 8 5 11 72 14 8 YI (--) 1.9 2.7 3.5
3.8 1.9 2.4 2.9 Pencil hardness of PC sheet -- -- B -- B HB F
Thickness (.mu.m) of PC sheet -- -- 240 -- 240 240 240 YI (--) of
PC sheet -- -- 0.93 -- 0.88 0.95 0.99
[0302] By comparison between Examples 1, 3 and 6 and Comparative
Example 4, as the blend ratio of the dihydroxy compound is the
same, the content of structural units derived from each dihydroxy
compound is estimated to be the same. Nevertheless, it is found
that the pencil hardness as specified by ISO 15184 in Examples 1, 3
and 6 is higher than the pencil hardness in Comparative Example 4.
A difference in the pencil hardness even with the same amount of
structural units contained is also shown in Examples 5 and 10 and
Comparative Example 5. Further, in Comparative Examples 1 and 2,
polycarbonate resin compositions by combination of polycarbonate
resins having no specific glass transition temperature are
employed, and in Comparative Example 1, it is found that the Charpy
impact strength is deteriorated, and the glass transition
temperature (Tg) is very low. Further, in Comparative Example 2, it
is found that although there are no problems in the pencil hardness
and the Charpy impact strength, the melt viscosity is very high,
the fluidity is not favorable, and the moldability is poor.
Example 2-1
[0303] A polycarbonate resin composition was obtained by
pelletizing in the same manner as in Example 1 except that as the
polycarbonate resin (a) and the polycarbonate resin (b), PC(a1) and
PC(b1) were melt-kneaded in a ratio as identified in Table 2-1.
[0304] The polycarbonate resin composition was subjected to
evaluation with respect to the surface hardness, the yellowness
index (YI), the glass transition temperature (Tg), the melting
viscosity and the Charpy impact strength in accordance with methods
as described in the above evaluation items. The results are shown
in Table 2-1.
Examples 2-2 to 2-7
[0305] Polycarbonate resin compositions in Examples 2-2 to 2-7 were
obtained in the same manner as in Example 1 except that two types
of polycarbonate resins as identified in Table 2-1 were
employed.
[0306] The polycarbonate resin compositions are subjected to
evaluation with respect to the surface hardness, the glass
transition temperature (Tg), the yellowness index (YI), the melt
viscosity and the Charpy impact strength in accordance with methods
as described in the above evaluation items. The results are shown
in Table 2-1.
[0307] Further, the polycarbonate resin compositions in Examples
2-6 and 2-7 were molded into extruded articles (sheets) by the
above method, which were subjected to evaluation with respect to
the pencil hardness and the yellowness index (YI). The results are
shown in Table 2-1.
Example 2-8
[0308] As the polycarbonate resin (a) and the polycarbonate resin
(b), pellets of PC(a2-6) and pellets of PC(b3) were dry-blended in
a ratio as identified in Table 2-1 to obtain a polycarbonate resin
composition in Example 2-8.
[0309] The polycarbonate resin composition was subjected to
evaluation with respect to the surface hardness, the yellowness
index (YI) and the Charpy impact strength in accordance with
methods as described in the above evaluation items. The results are
shown in Table 2-1 together with the amount of the polycarbonate
resin used.
[0310] Further, the polycarbonate resin composition was molded into
an extruded article (sheet) by the above method, which was
subjected to evaluation with respect to the pencil hardness and the
yellowness index (YI). The results are shown in Table 2-1.
Comparative Example 2-1
[0311] A polycarbonate resin composition in Comparative Example 2-1
was obtained in the same manner as in Example 2-1 except that
PC(b3) and the BPC monomer as identified in Table 2-1 were
employed.
[0312] The polycarbonate resin composition was subjected to
evaluation with respect to the surface hardness, the glass
transition temperature (Tg), the yellowness index (YI), the melt
viscosity and the Charpy impact strength in accordance with methods
as described in the above evaluation items. The results are shown
in Table 2-1.
Comparative Examples 2-2 to 2-5 and 2-8
[0313] Polycarbonate resin compositions in Comparative Examples 2-2
to 2-5 and 2-8 were obtained in the same manner as in Example 2-1
except that two types of polycarbonate resins as identified in
Table 2-1 were employed.
[0314] The polycarbonate resin compositions were subjected to
evaluation with respect to the surface hardness, the glass
transition temperature (Tg), the yellowness index (YI), the melt
viscosity and the Charpy impact strength. The results are shown in
Table 2-1.
[0315] Further, the polycarbonate resin compositions in Comparative
Examples 2-2 and 2-8 were molded into extruded articles (sheets) by
the above method, which were subjected to evaluation with respect
to the pencil hardness and the yellowness index (YI). The results
are shown in Table 2-1.
Comparative Examples 2-6, 2-7 and 2-9
[0316] The surface hardness, the glass transition temperature (Tg),
the yellowness index (YI), the melt viscosity and the Charpy impact
strength of PC(b3) in Comparative Example 2-6, PC(b2-1) in
Comparative Example 2-7 and PC(b2-2) in Comparative Example 2-9 by
themselves were evaluated. The results are shown in Table 2-1.
[0317] Further, the polycarbonate resin composition in Comparative
Example 2-6 was molded into an extruded article (sheet) by the
above method, which was subjected to evaluation with respect to the
pencil hardness and the yellowness index (YI). The results are
shown in Table 2-1.
TABLE-US-00003 TABLE 2-1 Polycarbonate resin (a) Polycarbonate
resin (b) Glass Glass transition Blending transition Blending temp.
amount Pencil temp. amount Pencil Type (.degree. C.) (wt %)
[.eta.]a hardness Type (.degree. C.) (wt %) [.eta.]b hardness Ex.
2-1 PC(a2-1) A1* 132 20 0.23 3H PC(b3) A6* 145 80 0.47 2B Ex. 2-2
PC(a2-2) A2* 125 20 0.07 3H PC(b3) A6* 145 80 0.47 2B Ex. 2-3
PC(a2-3) A2* 138 20 0.26 3H PC(b3) A6* 145 80 0.47 2B Ex. 2-4
PC(a2-4) A3* <100 20 0.06 2H PC(b3) A6* 145 80 0.47 2B Ex. 2-5
PC(a2-5) A4* 110 20 0.25 2H PC(b3) A6* 145 80 0.47 2B Ex. 2-6
PC(a2-6) A3* 101 20 0.18 2H PC(b3) A6* 145 80 0.47 2B Ex. 2-7
PC(a2-6) A3* 101 20 0.18 2H PC(b2-1) A6* 147 80 0.56 2B Ex. 2-8
PC(a2-6) A3* 101 20 0.18 2H PC(b3) A6* 145 80 0.47 2B Ex. 2-9
PC(a2-10) A5* 161 30 0.29 H PC(b3) A6* 145 70 0.47 2B Polycarbonate
resin composition Polycarbonate sheet Yellow- Glass Charpy
Comparison Yellow- Melt ness transition impact of pencil ness
Monomer unit (wt %) [.eta.]a/ Pencil viscosity index temp. strength
hardness Pencil Thickness index BPC BisOCZ BPA [.eta.]b hardness
(poise) (--) (.degree. C.) (kJ/m.sup.2) with PC(b) hardness (.mu.m)
(--) Ex. 2-1 -- 20 80 0.5 F 6,811 2.3 143 9 Three ranks -- -- -- up
(2B.fwdarw.F) Ex. 2-2 -- 20 80 0.15 F 2,546 1.9 126 6 Three ranks
-- -- -- up (2B.fwdarw.F) Ex. 2-3 -- 20 80 0.56 F 6,801 2.0 142 9
Three ranks -- -- -- up (2B.fwdarw.F) Ex. 2-4 20 -- 80 0.14 HB
5,013 2.4 128 8 Two ranks up -- -- -- (2B.fwdarw.HB) Ex. 2-5 20 --
80 0.53 F 5,161 3.2 138 8 Three ranks -- -- -- up (2B.fwdarw.F) Ex.
2-6 20 -- 80 0.39 F 3,506 2.3 134 9 Three ranks F 240 0.85 up
(2B.fwdarw.F) Ex. 2-7 20 -- 80 0.26 F 7,320 2.3 142 11 Three ranks
HB 240 0.85 up (2B.fwdarw.F) Ex. 2-8 20 -- 80 0.39 F 3,457 2.2 -- 9
Three ranks F 240 0.85 up (2B.fwdarw.F) Ex. 2-9 15 85 0.20 F -- 2.5
149 9 Three ranks -- -- -- up (2B.fwdarw.F) Polycarbonate resin (a)
Polycarbonate resin (b) Glass Glass transition Blending transition
Blending temp. amount Pencil temp. amount Pencil Type (.degree. C.)
(wt %) [.eta.]a hardness Type (.degree. C.) (wt %) [.eta.]b
hardness Comp. -- A7* -- 0.1 0.01 -- PC(b3) A6* 145 99.9 0.47 2B
Ex. 2-1 Comp. PC(a2-7) A3* 122 10 0.69 2H PC(b3) A6* 145 90 0.47 2B
Ex. 2-2 Comp. PC(a2-7) A3* 122 20 0.69 2H PC(b3) A6* 145 80 0.47 2B
Ex. 2-3 Comp. PC(a2-8) A4* 125 20 0.97 2H PC(b3) A6* 145 80 0.47 2B
Ex. 2-4 Comp. PC(a2-9) A1* 138 20 0.98 3H PC(b3) A6* 145 80 0.47 2B
Ex. 2-5 Comp. -- -- -- -- -- -- PC(b3) A6* 145 100 0.47 2B Ex. 2-6
Comp. -- -- -- -- -- -- PC(b2-1) A6* 147 100 0.56 2B Ex. 2-7 Comp.
PC(a2-7) A3* 122 20 0.69 2H PC(b2-1) A6* 147 80 0.56 2B Ex. 2-8
Comp. -- -- -- -- -- -- PC(b2-2) A8* 142 100 0.48 HB Ex. 2-9
Polycarbonate resin composition Polycarbonate sheet Yellow- Glass
Charpy Comparison Yellow- Melt ness transition impact of pencil
ness Monomer unit (wt %) [.eta.]a/ Pencil viscosity index temp.
strength hardness Pencil Thickness index BPC BisOCZ BPA [.eta.]b
hardness (poise) (--) (.degree. C.) (kJ/m.sup.2) with PC(b)
hardness (.mu.m) (--) Comp. 0.1 -- 99.9 0.01 2B 8,900 1.9 145 72 No
change -- -- -- Ex. 2-1 Comp. 10 -- 90 1.48 HB 9,417 2.8 143 12 Two
ranks F 240 0.86 Ex. 2-2 up (2B.fwdarw.HB) Comp. 20 -- 80 1.48 F
10,340 3.0 140 11 Three ranks -- -- -- Ex. 2-3 up (2B.fwdarw.F)
Comp. 20 -- 80 2.08 F 14,260 1.9 141 10 Three ranks -- -- -- Ex.
2-4 up (2B.fwdarw.F) Comp. -- 20 80 2.08 F 17,570 3.8 146 11 Three
ranks -- -- -- Ex. 2-5 up (2B.fwdarw.F) Comp. -- -- 100 -- 2B 9,010
1.9 145 72 No change B 240 0.88 Ex. 2-6 Comp. -- -- 100 -- 2B
19,200 2.0 146 75 No change -- -- -- Ex. 2-7 Comp. 20 -- 80 1.23 F
18,830 2.7 143 14 Three ranks F 240 0.86 Ex. 2-8 up (2B.fwdarw.F)
Comp. 20 -- 80 -- HB -- 2.7 142 6 -- -- -- -- Ex. 2-9 A1*: Bis-OCZ
homopolymer (interfacial method) A2*: Bis-OCZ homopolymer (melt
method) A3*: BPC homopolymer (melt method) A4*: BPC homopolymer
(interfacial method) A5*: CDOBC/BPA (50/50 wt %) copolymer A6*: BPA
homopolymer (melt method) A7*: BPC monomer A8*: BPA/BPC copolymer
(melt method)
[0318] By comparison between Examples 2-1 to 2-3 and Comparative
Example 2-6, it is found that in Examples 2-1 to 2-3, the pencil
hardness as specified by ISO 15184 is higher by three ranks than in
Comparative Example 2-6, the melt viscosity is lower than in
Comparative Example 2-6, and the moldability is improved. By
comparison between Example 2-4 and Comparative Example 2-1, it is
found that in Example 2-4, the pencil hardness as specific by ISO
15184 is high, and the melt viscosity is low. In Examples 2-5 to
2-7 and Comparative Example 2-9, as the blend ratio of the
dihydroxy compound is the same, the content of structural units
derived from each dihydroxy compound is estimated to be the same.
Nevertheless, it is found that the pencil hardness as specific by
ISO 15184 in Examples 2-5 to 2-7 is higher than the pencil hardness
in Comparative Example 2-9, the melt viscosity in Examples 2-5 to
2-7 is lower than the melt viscosity in Comparative Example 2-9,
and the moldability is improved. Further, by comparison between
Example 2-7 and Comparative Example 2-8, it is found that although
there is no difference in the pencil hardness, in Example 2-7, the
melt viscosity is low, and the yellowness index (YI) is
favorable.
[0319] The blending amount (wt %) of the dihydroxy compound of the
polycarbonate resins (a) and (b) used as materials of the
polycarbonate resin compositions in Examples and Comparative
Examples, the viscosity average molecular weight (Mv) and the
pencil hardness are shown in Table 3-1.
TABLE-US-00004 TABLE 3-1 Blend ratio (wt %) of Intrinsic
Abbreviated dihydroxy viscosity Pencil name compound Mv (.eta.)
hardness Ref. Ex. 3-1 BPC BPC (100) 17200 0.4 2H homopolymer (a3-1)
Ref. Ex. 3-2 BPC BPC (100) 18500 0.43 2H homopolymer (a3-2) Ref.
Ex. 3-3 BPC BPC (100) 30300 0.69 2H homopolymer (a3-3) Ref. Ex. 3-4
BisOC-Z BisOC-Z(100) 10200 0.23 3H homopolymer (a3-4) Ref. Ex. 3-5
BPC/BPA BPC/BPA 25200 0.55 F copolymer (30/70) (a3-5) Ref. Ex. 3-6
BPC/BPA BPC/BPA 24700 0.55 B copolymer (10/90) (a3-6) Ref. Ex. 3-7
BPA BPA (100) 20000 0.46 2B homopolymer (b3-1) Ref. Ex. 9 BPA BPA
(100) 20600 0.47 2B homopolymer (b3) Ref. Ex. 2-11 BPA BPA (100)
25600 0.56 2B homopolymer (b2-1)
Example 3-1
[0320] As the polycarbonate resin (a) and the polycarbonate resin
(b), PC(a3-1) and PC(b3-1) in a ratio as identified in Table 3-2
were melt-kneaded in a twin screw extruder (LABOTEX 30HSS-32)
manufactured by Japan Steel Works, Ltd. having one vent port,
extruded from the outlet of the twin screw extruder in the form of
strands, solidified by cooling with water, and pelletized by a
rotary cutter to obtain a molded article of polycarbonate resin. On
that occasion, the barrel temperature was 280.degree. C., and the
polycarbonate resin temperature at the outlet of the twin screw
extruder was 300.degree. C. At the time of melt-kneading, the vent
port of the twin screw extruder was connected to a vacuum pump, and
the pressure at the vent port was controlled to be 500 Pa.
[0321] This molded article of polycarbonate resin was subjected to
evaluation with respect to the surface hardness, the Charpy impact
strength, the yellowness index (YI), the content ([S]) of
structural units (a) on the surface of the molded article of
polycarbonate resin and the content ([T]) of structural units (a)
in the entire molded article of polycarbonate resin in accordance
with methods as disclosed in the above-described evaluation
items.
[0322] The results are shown in Table 3-2. In Example 3-1, the
structural units (a) are structural units derived from BPC.
Examples 3-2 to 3-4
[0323] Molded articles of polycarbonate resin in Examples 3-2 to
3-4 were obtained in the same manner as in Example 3-1 except that
two types of polycarbonate resins as identified in Table 3-2 were
employed. Further, the results of evaluation in the same manner as
in Example 3-1 are shown in Table 3-2. In Examples 3-2 and 3-3, the
structural units (a) are structural units derived from BPC, and in
Example 3-4, the structural units (a) are structural units derived
from Bis-OCZ.
Comparative Examples 3-1 to 3-4
[0324] Molded articles of polycarbonate resin in Comparative
Examples 1 to 4 were obtained in the same manner as in Example 1
except that two types of polycarbonate resins as identified in
Table 3-2 were employed. Further, the results of evaluation in the
same manner as in Example 3-1 are shown in Table 3-2. In
Comparative Examples 3-1 and 3-4, the structural units (a) are
structural units derived from BPC.
Comparative Examples 3-5 to 3-8
[0325] Molded articles of polycarbonate resin in Comparative
Examples 3-5 to 3-8 were obtained by using PC(a3-2) in Comparative
Example 3-5, PC(b3) in Comparative Example 3-6, PC(a3-5) in
Comparative Example 3-7 and PC(a3-6) in Comparative Example 3-8 by
themselves as shown in Table 3-2. Further, the results of
evaluation in the same manner as in Example 3-1 are shown in Table
3-2. In Comparative Examples 3-5, 3-7 and 3-8, the structural units
(a) are structural units derived from BPC, and in Comparative
Example 3-6, the structural units (a) are structural units derived
from BPA.
TABLE-US-00005 TABLE 3-2 Molded article of polycarbonate resin
Content of Content of Structural units Pencil Polycarbonate resin
(a) Polycarbonate resin (b) structural units structural units (a)
content ratio hardness on Blend- Blend- (a) on the (a) in the
between surface the surface Charpy ing ing Struc- surface of entire
molded layer/the entire of molded impact amount amount tural molded
article article [S]/[T] article strength Type wt % Type wt % units
(a) wt % wt % -- -- kJ/m.sup.2 Ex. 3-1 BPC 20 BPA 80 BPC 23 20 1.15
F 11 homopolymer homopolymer (a3-1) (b3-1) Ex. 3-2 BPC 10 BPA 90
BPC 11 10 1.1 F 14 homopolymer homopolymer (a3-2) (b3) Ex. 3-3 BPC
10 BPA 90 BPC 10.5 10 1.05 HB 17 homopolymer homopolymer (a3-2)
(b2-1) Ex. 3-4 BisOC-Z 20 BPA 10 BisOC-Z 22 20 1.1 F 9 homopolymer
homopolymer (a3-4) (b1) Comp. BPC 50 BPA 50 BPC 49 50 0.98 H 7 Ex.
3-1 homopolymer homopolymer (a3-2) (b1) Comp. BPC 20 BPA 80 BPC 20
20 1.0 HB 11 Ex. 3-2 homopolymer homopolymer (a3-3) (b4-1) Comp.
BPC 10 BPA 90 BPC 10 10 1.0 HB 14 Ex. 3-3 homopolymer homopolymer
(a3-3) (b1) Comp. BPC 10 BPA 80 BPC 10 10 1.0 B 10 Ex. 3-4
homopolymer homopolymer (a3-3) (b2-1) Comp. BPC 100 -- -- BPC 100
100 1.0 2H 6 Ex. 3-5 homopolymer (a3-2) Comp. -- -- BPA 100 -- 100
100 1.0 2B 72 Ex. 3-6 homopolymer (b3) Comp. BPA/BPC 70/30 -- --
BPC 30 30 1.0 F 8 Ex. 3-7 copolymer (a3-5) Comp. BPA/BPC 90/10 --
-- BPC 10 10 1.0 B 14 Ex. 3-8 copolymer (a3-6)
[0326] By comparison between Example 3-1 and Comparative Example
3-2, although the content ([T]) of the structural units (a)
(structural units derived from BPC) in the entire molded article of
polycarbonate resin is the same, it is found that in Example 3-1,
the content ([S]) of the structure units (a) on the surface of the
molded article of polycarbonate resin is high, and the pencil
hardness as specified by ISO 15184 in Example 3-1 is higher than
the pencil hardness in Comparative Example 3-2.
[0327] Likewise, by comparison between Example 3-2 and Comparative
Examples 3-3 and 3-8, although the content ([T]) of the structural
units (a) (structural units derived from BPC) in the entire molded
article of polycarbonate resin is the same, it is found that in
Example 3-2, the content ([S]) of the structural units (a)
(structural units derived from BPC) on the surface of the molded
article of polycarbonate resin is high, and the pencil hardness as
specified by ISO 15184 is high, as compared with Comparative
Examples 3-3 and 3-8.
INDUSTRIAL APPLICABILITY
[0328] According to the present invention, it is possible to obtain
a polycarbonate resin composition and a molded article, which have
a particularly excellent surface hardness and which have excellent
heat resistance, moldability (fluidity), color, impact resistance,
flame retardancy and the like, by a simple method. This molded
article is applicable particularly to applications for which the
surface hardness is required, such as electric/electronic equipment
fields such as cellular phones and personal computers, automobile
fields such as headlamp lenses and windows for vehicles, and
building material fields such as illumination and exterior.
[0329] This application is a continuation of PCT Application No.
PCT/JP2011/058336, filed on Mar. 31, 2011, which is based upon and
claims the benefit of priority from Japanese Patent Application No.
2010-083181 filed on Mar. 31, 2010, Japanese Patent Application No.
2010-262055 filed on Nov. 25, 2010, Japanese Patent Application No.
2010-262056 filed on Nov. 25, 2010, Japanese Patent Application No.
2011-018525 filed on Jan. 31, 2011, Japanese Patent Application No.
2011-018526 filed on Jan. 31, 2011, Japanese Patent Application No.
2011-047877 filed on Mar. 4, 2011 and Japanese Patent Application
No. 2011-076450 filed on Mar. 30, 2011. The contents of those
applications are incorporated herein by reference in its
entirety.
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