U.S. patent application number 15/467880 was filed with the patent office on 2017-07-13 for curable composition and polymer.
This patent application is currently assigned to MITSUBISHI RAYON CO., LTD.. The applicant listed for this patent is MITSUBISHI RAYON CO., LTD.. Invention is credited to Fuminori Nakaya, Tetsuya NODA, Hajime Okutsu.
Application Number | 20170198076 15/467880 |
Document ID | / |
Family ID | 47259373 |
Filed Date | 2017-07-13 |
United States Patent
Application |
20170198076 |
Kind Code |
A1 |
NODA; Tetsuya ; et
al. |
July 13, 2017 |
CURABLE COMPOSITION AND POLYMER
Abstract
An object of the invention is to provide a curable composition
having a HALS skeleton and capable of producing polymers having
excellent weather resistance and outer appearance. The present
invention provides a curable composition including at least a
monomer component that contains a monomer (A) represented by a
certain formula and a monomer (B) polymerizable with the monomer
(A). In the curable composition, the content of the monomer (A) is
0.01 to 35 mol % in the monomer component, and the content of the
monomer (B) is 65 to 99.99 mol % in the monomer component.
Inventors: |
NODA; Tetsuya; (Hiroshima,
JP) ; Nakaya; Fuminori; (Hiroshima, JP) ;
Okutsu; Hajime; (Aichi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
MITSUBISHI RAYON CO., LTD. |
CHIYODA-KU |
|
JP |
|
|
Assignee: |
MITSUBISHI RAYON CO., LTD.
CHIYODA-KU
JP
|
Family ID: |
47259373 |
Appl. No.: |
15/467880 |
Filed: |
March 23, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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14123147 |
Nov 29, 2013 |
9663603 |
|
|
PCT/JP2012/064024 |
May 31, 2012 |
|
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15467880 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08F 220/36 20130101;
C08F 220/14 20130101; C08F 2/46 20130101; C08F 220/14 20130101;
C09D 133/16 20130101; C08L 2312/00 20130101; C09D 133/12 20130101;
C08F 226/06 20130101; C08F 2/38 20130101; C08F 2/54 20130101; C08F
220/14 20130101; C08F 220/14 20130101; C08F 2/48 20130101; C08F
2/50 20130101; C08F 26/06 20130101; C08J 5/18 20130101; C08F
222/1006 20130101; C08F 222/1006 20130101; C09D 139/04 20130101;
C08F 220/60 20130101; C08J 2333/12 20130101; C08F 226/06 20130101;
C08F 220/36 20130101; C08F 226/06 20130101; C08F 220/36
20130101 |
International
Class: |
C08F 220/14 20060101
C08F220/14; C09D 133/12 20060101 C09D133/12; C08J 5/18 20060101
C08J005/18 |
Foreign Application Data
Date |
Code |
Application Number |
May 31, 2011 |
JP |
2011-121776 |
Claims
1. A resin sheet produced by polymerizing an active energy ray
curable composition, the curable composition comprising: a monomer
component comprising a monomer (A) of formula (1) and a monomer (B)
polymerizable with the monomer (A), wherein a content of the
monomer (A) is 0.01 to 35 mol % in the monomer component, and a
content of the monomer (B) is 65 to 99.99 mol % in the monomer
component, ##STR00013## wherein R.sup.1 is a hydrogen atom or a
methyl group; X is an imino group, a compound of formula (2) or a
compound of formula (3); and R.sup.2, R.sup.3 and R.sup.4 each
independently are a hydrogen atom, a linear alkyl group comprising
from 1 to 8 carbon atoms, a branched linear alkyl group comprising
from 1 to 8 carbon atoms, a substituted or unsubstituted cycloalkyl
group comprising from 6 to 8 carbon atoms, or a substituted or
unsubstituted aryl group comprising 6 to 12 carbon atoms; and a
combination of R.sup.2 and R.sup.3, R.sup.2 and R.sup.4, R.sup.3
and R.sup.4, or R.sup.2, R.sup.3 and R.sup.4 optionally form a ring
structure and the ring structure optionally has a substituted
group, ##STR00014## wherein n is an integer of 1 to 10; R.sup.5 and
R.sup.6 each are a hydrogen atom or a methyl group; and at least
one of R.sup.5 and R.sup.6 represents a hydrogen atom, ##STR00015##
wherein n is an integer of 1 to 10.
2. The resin sheet according to claim 1, wherein the curable
composition further comprises a polymer comprising a monomer (C)
polymerizable with the monomer (A).
3. The resin sheet according to claim 1, wherein the monomer (B)
contains methyl methacrylate at content of 50 mol % or more.
4. The resin sheet according to claim 1, wherein the curable
composition further comprises at least one polymerization initiator
(D) selected from the group consisting of benzoin, benzoin
monomethyl ether, benzoin isopropyl ether, acetoin, benzophenone,
p-methoxybenzophenone, diethoxyacetophenone, benzyl dimethyl ketal,
1-hydroxycyclohexyl phenyl ketone, methyl phenyl glyoxylate,
2-hydroxy-2-methyl-1-phenylpropane-1-on, tetramethyl thiuram
monosulphide, tetramethyl thiuram disulphide,
2,4,6-trimethylbenzoyl diphenylphosphine oxide,
2,4,6-trimethylbenzoyl phenylethoxy phosphine oxide,
bis(2,4,6-trimethylbenzoyl)-phenyl phosphine oxide,
bis(2,6-dimethoxybenzoyl)-2,4,4-trimethyl-pentylphosphine oxide,
2-benzyl-2-dimethylamino-1-(4-morpholino phenyl) butanone-1 and
camphorquinone.
5. The resin sheet according to claim 1, wherein the curable
composition further comprises at least one ultraviolet absorber (E)
selected from the group consisting of
2-hydroxy-4-octoxybenzophenone, 2,4-dihydroxybenzophenone,
2-(2-hydroxy-tert-butylphenyl) benzotriazole, and
2-[4-(octyl-2-methylethanoate)oxy-2-hydroxyphenyl]-4,6-[bis(2,4-dimet-
hylphenyl)]-1,3,5-triazine.
6. The resin sheet according to claim 1, wherein a total light
transmittance is from 85 to 100%, and a haze value is less than
5%.
7. The resin sheet according to claim 2, wherein a total light
transmittance is from 85 to 100%, and a haze value is less than
5%.
8. The resin sheet according to claim 3, wherein a total light
transmittance is from 85 to 100%, and a haze value is less than
5%.
9. The resin sheet according to claim 4, wherein a total light
transmittance is from 85 to 100%, and a haze value is less than
5%.
10. The resin sheet according to claim 5, wherein a total light
transmittance is from 85 to 100%, and a haze value is less than
5%.
11. A cured coating film produced by applying an active energy ray
curable composition comprising a monomer component comprising a
monomer (A) of formula (1) and a monomer (B) polymerizable with the
monomer (A) on a substrate, and subsequently polymerizing the
curable composition, thereby obtaining the cured coating film,
wherein a content of the monomer (A) is 0.01 to 35 mol % in the
monomer component, and a content of the monomer (B) is 65 to 99.99
mol % in the monomer component, ##STR00016## wherein R.sup.1 is a
hydrogen atom or a methyl group; X is an imino group, a compound of
formula (2) or a compound of formula (3); and R.sup.2, R.sup.3 and
R.sup.4 each independently are a hydrogen atom, a linear alkyl
group comprising from 1 to 8 carbon atoms, a branched linear alkyl
group comprising from 1 to 8 carbon atoms, a substituted or
unsubstituted cycloalkyl group comprising from 6 to 8 carbon atoms,
or a substituted or unsubstituted aryl group comprising 6 to 12
carbon atoms; and a combination of R.sup.2 and R.sup.3, R.sup.2 and
R.sup.4, R.sup.3 and R.sup.4, or R.sup.2, R.sup.3 and R.sup.4
optionally form a ring structure and the ring structure optionally
has a substituted group, ##STR00017## wherein n is an integer of 1
to 10; R.sup.5 and R.sup.6 each are a hydrogen atom or a methyl
group; and at least one of R.sup.5 and R.sup.6 represents a
hydrogen atom, ##STR00018## wherein n is an integer of 1 to 10.
12. The cured coating film according to claim 11, wherein the
curable composition further comprises a polymer comprising a
monomer (C) polymerizable with the monomer (A).
13. The cured coating film according to claim 11, wherein the
monomer (B) comprises methyl methacrylate at content of 50 mol % or
more.
14. The cured coating film according to claim 11, wherein the
curable composition further comprises at least one polymerization
initiator (D) selected from the group consisting of benzoin,
benzoin monomethyl ether, benzoin isopropyl ether, acetoin,
benzophenone, p-methoxybenzophenone, diethoxyacetophenone, benzyl
dimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, methyl phenyl
glyoxylate, 2-hydroxy-2-methyl-1-phenylpropane-1-on, tetramethyl
thiuram monosulphide, tetramethyl thiuram disulphide,
2,4,6-trimethylbenzoyl diphenylphosphine oxide,
2,4,6-trimethylbenzoyl phenylethoxy phosphine oxide,
bis(2,4,6-trimethylbenzoyl)-phenyl phosphine oxide,
bis(2,6-dimethoxybenzoyl)-2,4,4-trimethyl-pentylphosphine oxide,
2-benzyl-2-dimethylamino-1-(4-morpholino phenyl) butanone-1 and
camphorquinone. [0058]
15. The cured coating film according to claim 11, wherein the
curable composition further comprises at least one ultraviolet
absorber (E) selected from the group consisting of
2-hydroxy-4-octoxybenzophenone, 2,4-dihydroxybenzophenone,
2-(2-hydroxy-tert-butylphenyl) benzotriazole, and
2-[4-(octyl-2-methylethanoate)oxy-2-hydroxyphenyl]-4,6-[bis(2,4-dimet-
hylphenyl)]-1,3,5-triazine. [0061]
16. The cured coating film according to claim 11, wherein a total
light transmittance is from 85 to 100%, and a haze value is less
than 5%.
17. The cured coating film according to claim 12, wherein a total
light transmittance is from 85 to 100%, and a haze value is less
than 5%.
18. The cured coating film according to claim 13, wherein a total
light transmittance is from 85 to 100%, and a haze value is less
than 5%.
19. The cured coating film according to claim 14, wherein a total
light transmittance is from 85 to 100%, and a haze value is less
than 5%.
20. The cured coating film according to claim 15, wherein a total
light transmittance is from 85 to 100%, and a haze value is less
than 5%.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional application of U.S.
application Ser. No. 14/123,147, filed on Nov. 29, 2013, which is a
national stage entry application of PCT/JP2012/064024, filed on May
31, 2012, the text of which is incorporated by reference, and
claims foreign priority to JP 2011-121776, filed on May 31, 2011,
the entire contents of which are incorporated herein by
reference.
TECHNICAL FIELD
[0002] The present invention relates to a curable composition.
BACKGROUND ART
[0003] As has been well known, ultraviolet rays in the sunlight
degrades polymers by breaking the chemical bonds in the polymers.
In order to prevent such degradation, light stabilizers,
ultraviolet absorbers, or the like are added to polymer products
such as plastics, fibers, and paints. In particular, a hindered
amine light stabilizer (hereinafter referred to as HALS) is said to
have a function of preventing a polymer material from being
degraded because the HALS hardly absorb the ultraviolet ray while
efficiently scavenging harmful free radicals generated by
ultraviolet rays.
[0004] A typical HALS, however, is not chemically bonded to a
polymer material. Thus, the HALS may bleed out from the polymer
material if exposed outdoors for a long time. Therefore, it has
been pointed out that such bleeding out of the HALS may lead to the
loss of the original functions of the HALS. For suppressing the
bleeding out of the HALS from the polymer material, a high
molecular weight HALS prepared from methacrylic acid piperidyl
ester has been studied (see, Patent Documents 1 to 3).
CITATION LIST
Patent Literature
Patent Document 1: JP-A-10-176016
Patent Document 2: JP-A-2008-56906
Patent Document 3: JP-T-2000-509082
SUMMARY OF INVENTION
Technical Problem
[0005] However, when the compounds disclosed in Patent Documents 1
to 3 are applied to active energy ray-curable resins, phase
separation may be caused depending on the amounts of the compounds
added as well as the types of the resins. In addition, when such
compounds are applied to active energy ray-curable resins, such
compounds may not effectively provide the effects as the HALS in
the presence of acids.
[0006] Hence, the present invention intends to provide a curable
composition capable of producing a polymer having a HALS skeleton
with excellent weather resistance and outer appearance.
Solutions to Problem
[0007] The following aspects of the invention [1] to [8] are
solutions to the above problem.
[1] A curable composition that contains a monomer component
containing: a monomer (A) represented by formula (1) below; and a
monomer (B) polymerizable with the monomer (A), in which
[0008] the content of the monomer (A) is 0.01 to 35 mol % in the
monomer component, and
[0009] the content of the monomer (B) is 65 to 99.99 mol % in the
monomer component.
##STR00001##
[0010] In the formula (1), R.sup.1 represents a hydrogen atom or a
methyl group; X represents an oxygen atom, an imino group, a
compound represented by formula (2) below or a compound represented
by formula (3) below; and R.sup.2, R.sup.3 and R.sup.4 each
represent a hydrogen atom, a linear alkyl group having 1 to 8
carbon atoms, a branched linear alkyl group having 1 to 8 carbon
atoms, a substituted or unsubstituted cycloalkyl group having 6 to
8 carbon atoms, or a substituted or unsubstituted aryl group having
6 to 12 carbon atoms, where R.sup.2, R.sup.3 and R.sup.4 may be the
same or different from one another, a combination of R.sup.2 and
R.sup.3, R.sup.2 and R.sup.4, R.sup.3 and R.sup.4, or R.sup.2,
R.sup.3 and R.sup.4 may form a ring structure and the ring
structure may have a substituted group.
##STR00002##
[0011] In the formula (2), n representing an integer of 1 to 10;
R.sup.5 and R.sup.6 each represents a hydrogen atom or a methyl
group; and at least one of R.sup.5 and R.sup.6 represents a
hydrogen atom.
##STR00003##
[0012] In the formula (3), n represents an integer of 1 to 10.
[2] The curable composition according to the above [1], further
including a polymer containing a monomer (C) polymerizable with the
monomer (A). [3] The curable composition according to the above [1]
or [2], in which the monomer (B) contains methyl methacrylate at
the content of 50 mol % or more. [4] A method of manufacturing a
polymer, including: polymerizing the curable composition according
to any one of the above [1] to [3] with irradiation of active
energy ray. [5] A resin sheet produced by polymerizing the curable
composition according to any one of the above [1] to [3]. [6] The
resin sheet according to the above [5], in which the total light
transmittance is 85 to 100%, and haze value is less than 5%. [7] A
cured coating film produced by applying the curable composition
according to any one of the above [1] to [3] to a substrate and
subsequently polymerizing the curable composition. [8] The cured
coating film according to the above [7], in which the total light
transmittance is 85 to 100%, and haze value is less than 5%.
Effects of Invention
[0013] Using the curable composition according to any aspect of the
invention, a polymer with excellent weather resistance and outer
appearance can be obtained.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a schematic diagram illustrating an exemplary
apparatus for producing a resin sheet.
DESCRIPTION OF EMBODIMENTS
[0015] The curable composition according to the invention includes
at least a monomer component that includes: a polymerizable monomer
(A) having a HALS skeleton serving as a light stabilizer; and a
monomer (B) polymerizable with the monomer (A). The curable
composition may further contain a radical polymerization initiator
(C). The polymerization of the curable composition may be initiated
by active energy rays.
[0016] Since the polymer obtained from the curable composition
according to the invention includes the polymerizable monomer unit
having the HALS skeleton, the polymer can be prevented from
bleeding out even after experiencing a weather resistant test for a
long time. In addition, since the monomer (A) is favorably
compatible with the monomer (B) added to the composition, the
obtained polymer can be highly transparent and excellent in outer
appearance.
[0017] In the description made below, the invention will be
described in detail.
[0018] <Monomer (A)>
[0019] The polymerizable monomer (A) having the HALS skeleton
(hereinafter abbreviated as monomer (A)) is represented by the
following formula (1).
##STR00004##
[0020] In the formula (1), R.sup.1 represents a hydrogen atom or a
methyl group. X represents an oxygen atom, an imino group, a
compound represented by formula (2) below or a compound represented
by formula (3) below. R.sup.2, R.sup.3 and R.sup.4 each represent a
hydrogen atom, a linear alkyl group having 1 to 8 carbon atoms, a
branched linear alkyl group having 1 to 8 carbon atoms, a
substituted or unsubstituted cycloalkyl group having 6 to 8 carbon
atoms, or a substituted or unsubstituted aryl group having 6 to 12
carbon atoms. R.sup.2, R.sup.3 and R.sup.4 may be the same or
different from one another. Further, a combination of R.sup.2 and
R.sup.3, R.sup.2 and R.sup.4, R.sup.3 and R.sup.4, or R.sup.2,
R.sup.3 and R.sup.4 may form a ring structure. Such ring structure
may have a saturated group.
##STR00005##
[0021] In the formula (2), n represents an integer of 1 to 10.
R.sup.5 and R.sup.6 each represent a hydrogen atom or a methyl
group. At least one of R.sup.5 and R.sup.6 represents a hydrogen
atom.
##STR00006##
[0022] In the formula (3), n represents an integer of 1 to 10.
[0023] In the formula (1), X preferably represents an oxygen atom.
With such configuration, the synthesis of the monomer (A) is
facilitated. Further, in the formula (2), R.sup.5 and R.sup.6 both
preferably represent hydrogen atoms respectively because of ease of
synthesis of the monomer (A).
[0024] In the formula (1), X is represented such that an oxygen
atom at the right end of the compound represented by any of the
formulae (2) and (3) is bonded to the carbon atom of the piperidine
ring in the formula (1).
[0025] In the above formula (1), it is preferred that (i) R.sup.2
to R.sup.4 all represent hydrogen atoms, and alternatively (ii) any
two of R.sup.2 to R.sup.4 preferably represent hydrogen atoms while
one of the remainder represents a linear alkyl group having 1 to 8
carbon atoms or a branched linear alkyl group having 1 to 8 carbon
atoms. With this configuration, the coloring at the time of the
polymerization or the molding is reduced, and the obtained products
have favorable weather resistance.
[0026] When the monomer (B) contains methyl methacrylate at the
content of 50 mol % or more and the polymer (C) contains methyl
methacrylate unit at the content of 50 mass % or more, the number
of the carbon atoms contained in the linear or branched linear
alkyl group is preferably 1 to 6 and more preferably 1 to 4. With
this configuration, favorable compatibility is obtained.
[0027] Examples of the substitute are a linear or branched linear
alkyl group having 1 to 4, a hydroxyl group, a phosphate ester
group or a halogen atom.
[0028] Examples of the monomer (A) are
1-octyloxy-2,2,6,6-tetramethyl-4-(meth) acryloyloxy piperidine,
1-octyloxy-2,2,6,6-tetramethyl-4-(meth) acrylamide piperidine,
1-propyloxy-2,2, 6, 6-tetramethyl-4-(meth)acryloyloxy piperidine,
1-propyloxy-2,2,6,6-tetramethyl-4-(meth)acrylamide piperidine,
1-cyclohexyloxy-2,2,6,6-tetramethyl-4-(meth)acryloyloxy piperidine,
1-cyclohexyloxy-2,2,6,6-tetramethyl-4-(meth)acrylamide piperidine,
1-methyloxy-2,2, 6, 6-tetramethyl-4-(meth)acryloyloxy piperidine,
1-methyloxy-2,2,6,6-tetramethyl-4-(meth)acrylamide piperidine,
1-octyloxy-2,2, 6,6-tetramethyl-4-(2-(2-(meth)acryloyl
oxy)ethoxy)ethoxy piperidine, and
1-octyloxy-2,2,6,6-tetramethyl-4-(4-(2-(meth)acryloyloxy)ethoxy-1,4-dioxo-
) butoxy piperidine.
[0029] Among the above compounds, the preferable compounds are
1-methyloxy-2,2,6,6-tetramethyl-4-(meth)acryloyloxy piperidine,
1-propyloxy-2,2,6,6-tetramethyl-4-methacryloyloxy piperidine,
1-octyloxy-2,2,6,6-tetramethyl-4-(2-(2-methacryloyloxy)ethoxy)ethoxy
piperidine, 1-octyloxy-2,2,6, 6-tetramethyl-4-(4-(2-methacryloyl
oxy)ethoxy-1,4-dioxo) butoxy piperidine, and
1-octyloxy-2,2,6,6-tetramethyl-4-(meth) acryloyloxy piperidine.
Thus, the obtained products can have favorable weather
resistance.
[0030] The monomer (A) may be a single compound or a combination of
two or more compounds.
[0031] In this description, (meth) acryl means acryl or methacryl.
In addition, (meth) acryloyl means acryloyl or methacryloyl.
[0032] The monomer (A) can be synthesized by a known method.
[0033] For instance,
1-octyloxy-2,2,6,6-tetramethyl-4-methacryloyloxy piperidine
(hereinafter referred to as "monomer unit (A-1)") is synthesized in
the following manner. Specifically, in the presence of sodium
tungstate, 4-hydroxy-2,2,6,6-tetramethyl piperidine is oxidized
using hydrogen peroxide solution of 30% concentration. Then, the
hydroxyl group contained in the obtained
4-hydroxy-2,2,6,6-tetramethyl piperidine-N-oxide is protectively
acetylated with acetic acid anhydride. By using octane as the
solvent and the reactant, the 4-hydroxy-2,2,6,6-tetramethyl
piperidine-N-oxide is reacted with t-butyl hydroperoxide, so that
the acetyl protection is deprotected. Subsequently, the
4-hydroxy-2,2,6,6-tetramethyl piperidine-N-oxide is reacted with
methacryloyl chloride, and the monomer (A-1) is synthesized.
[0034] Further, the synthesis of the monomer (A-1) can be conducted
by a method disclosed in JP-T-2008-519003.
[0035] Specifically, in the presence of sodium tungstate dehydrate,
triacetonamine is oxidized using hydrogen peroxide solution of 30%
concentration, and converted into triacetoneamine-N-oxide. Then,
the triacetoneamine-N-oxide is reacted with 1-octane and t-butyl
hydroperoxide, and reduced by Ru-supported charcoal and hydrogen.
The thus-obtained mixture of
4-hydroxy-1-(1-octyloxy)-2,2,6,6-tetramethyl piperidine and
4-hydroxy-1-(3-octyloxy)-2,2,6,6-tetramethyl piperidine is reacted
with methacryloyl chloride, and the monomer (A-1) is
synthesized.
[0036] In addition,
1-propyloxy-2,2,6,6-tetramethyl-4-methacryloyloxy piperidine
(hereinafter referred to as "monomer (A-2)") can be synthesized
according to the method disclosed in JP-T-2008-519003, using
propylene in place of 1-octane.
[0037] Further,
1-octyloxy-2,2,6,6-tetramethyl-4-(2-(2-methacryloyloxy)ethoxy)
ethoxy piperidine (hereinafter referred to as "monomer (A-3)") is
synthesized in the following manner. Specifically, the hydroxyl
group contained in 2,2,6,6-tetramethyl-4-(2-(2-hydroxy
ethoxy)ethoxy piperidine-N-oxide is protectively acetylated using
acetic acid anhydride. By using octane as the solvent and the
reactant, the 2,2,6,6-tetramethyl-4-(2-(2-hydroxy ethoxy)ethoxy
piperidine-N-oxide is reacted with t-butyl hydroperoxide, so that
the acetyl protection is deprotected. Subsequently, the
2,2,6,6-tetramethyl-4-(2-(2-hydroxy ethoxy)ethoxy
piperidine-N-oxide is reacted with methacryloyl chloride, and the
monomer (A-3) is synthesized.
[0038] Further,
1-octyloxy-2,2,6,6-tetramethyl-4-(4-(2-methacryloyloxy)ethoxy-1,4-dioxy)
butoxy piperidine (hereinafter referred to as "monomer (A-4)") is
synthesized in the following manner. Specifically, in the presence
of sodium tungstate, 4-hydroxy-2,2,6,6-tetramethyl piperidine is
oxidized using hydrogen peroxide solution of 30% concentration.
Then, the hydroxyl group in the obtained
4-hydroxy-2,2,6,6-tetramethyl piperidine-N-oxide is protectively
acetylated using acetic acid anhydride. By using octane as the
solvent and the reactant, the 4-hydroxy-2,2,6,6-tetramethyl
piperidine-N-oxide is reacted with t-butyl hydroperoxide, so that
the acetyl protection is deprotected. Subsequently, succinic
anhydride is added. By subjecting the obtained carboxylic acid and
2-hydroxyethyl methacrylate to dehydration condensation, the
monomer (A-4) is synthesized.
[0039] In addition,
1-methyloxy-2,2,6,6-tetramethyl-4-methacryloyloxy piperidine
(hereinafter referred to as "monomer unit (A-5)") is synthesized in
the following manner. Specifically, according to the method
disclosed in JP-T-2009-541428,
1-methyloxy-2,2,6,6-tetramethyl-4-hydroxy piperidine is
synthesized. Then, the obtained
1-methyloxy-2,2,6,6-tetramethyl-4-hydroxy piperidine is reacted
with methacryloyl chloride, and the monomer (A-5) is
synthesized.
[0040] More specifically, in the presence of copper chloride (I),
2,2,6,6-tetramethyl-4-hydroxy piperidine-N-oxide is reacted with
acetone and hydrogen peroxide solution of 30% concentration. Then,
the obtained 1-methyloxy-2,2,6,6-tetramethyl-4-hydroxy piperidine
is reacted with methacryloyl chloride, and the monomer (A-5) is
synthesized.
[0041] The content of the monomer (A) in the monomer component is
0.01 to 35 mol %, preferably 0.05 to 20 mol %, and more preferably
0.05 to 5 mol %. When the content of the monomer (A) is 0.01 mol %
or more, the cured coating film has sufficient weather resistance.
As the result, the degradation of the cured coating film is
effectively prevented. When the content of the monomer (A) is 35
mol % or less, the insufficient curing of the coating is
effectively prevented. As the result, the toughness, heat
resistance and wear resistance of the cured coating film are
further enhanced.
[0042] <Monomer (B)>
[0043] The monomer (B) is a polymerizable monomer other than the
monomer (A). The monomer (B) is not limited to a specific one as
long as it is polymerizable with the monomer (A). Examples of the
monomer (B) are monofunctional (meth)acrylate or polyfunctional
(meth)acrylate. The monomer (B) may be suitably selected according
to the required specifications of the coating. Other examples of
the polymerizable monomer usable as the monomer (B) are urethane
(meth)acrylate, epoxy (meth)acrylate, polyester (meth)acrylate, or
a monomer having a polymerizable unsaturated bond such as
organic-inorganic hybrid (meth)acrylate obtained by condensing
colloidal silica and (meth) acryloyloxy alkoxysilane.
[0044] Examples of monofunctional (meth)acrylate applicable as the
monomer (B) are mono(meth)acrylate such as methyl (meth)acrylate,
ethyl (meth)acrylate, butyl (meth)acrylate, propyl (meth)acrylate,
n-butyl (meth)acrylate, i-butyl (meth)acrylate, t-butyl
(meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate,
lauryl (meth)acrylate, stearyl (meth)acrylate, morpholyl
(meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl
(meth)acrylate, 4-hydroxybutyl (meth)acrylate, glycidyl
(meth)acrylate, dimethylaminoethyl (meth)acrylate,
diethylaminoethyl (meth)acrylate, tricyclodecane (meth)acrylate,
polyethyleneglycol mono (meth)acrylate, cyclohexyl (meth)acrylate,
tetrahydrofurfuryl (meth)acrylate, dicyclopentanyl (meth)acrylate,
dicyclopentenyl (meth)acrylate, isobornyl (meth)acrylate, allyl
(meth)acrylate, 2-ethoxyethyl (meth)acrylate, benzyl
(meth)acrylate, phenoxyethyl (meth)acrylate or phenyl
(meth)acrylate, or mono(meth)acrylate compound such as an adduct of
acid phthalic anhydride and 2-hydroxyethyl (meth)acrylate.
[0045] Examples of polyfunctional (meth)acrylate applicable as the
monomer (B) are neopentyl glycol di(meth)acrylate, ethylene glycol
di(meth)acrylate, polyethylene glycol (repeating unit number
(hereinafter referred to as "n") is 2 to 15) di(meth)acrylate,
polypropylene glycol (n=2 to 15) di(meth)acrylate, polybutylene
glycol (n=2 to 15) di(meth)acrylate, 2,2-bis(4-(meth)acryloxyethoxy
phenyl) propane, 2,2-bis (4-(meth)acryloxydiethoxy phenyl) propane,
trimethylolpropane diacrylate, bis (2-(meth)acryloxyethyl) hydroxy
ethyl isocyanurate, trimethylolpropane tri(meth)acrylate,
tris(2-(meth)acryl oxyethyl) isocyanurate, pentaerythritol
tri(meth)acrylate, pentaerythritol tetra(meth)acrylate,
dipentaerythritol tetra(meth)acrylate, dipentaerythritol
penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, epoxy
poly(meth)acrylate such as epoxy di(meth)acrylate formed by
reacting bisphenol A diepoxy with (meth) acrylic acid, urethane
poly(meth)acrylate such as urethane tri(meth)acrylate formed by
reacting trimer of 1, 6-hexamethylene diisocyanate with 2-hydroxy
ethyl (meth)acrylate, urethane di(meth)acrylate formed by reacting
isophorone diisocyanate with 2-hydroxy propyl (meth)arylate,
urethane hexa(meth)acrylate formed by reacting isophorone
diisocyanate with pentaerythritol tri(meth)acrylate, urethane
di(meth)acrylate formed by reacting dicyclo methane diisocyanate
with 2-hydroxy ethyl (meth)acrylate, or urethane di(meth)acrylate
formed by reacting 2-hydroxy ethyl (meth)acrylate with an urethane
reactant of dicyclo methane diisocyanate and poly(n=6 to 15)
tetramethylene glycol, polyester (meth)acrylate formed by reacting
trimethylolethane with succinic acid and (meth) acrylic acid, or
polyester poly(meth)acrylate such as polyester (meth)acrylate
formed by reacting trimethylol propane with succinic acid, ethylene
glycol and (meth) acrylic acid.
[0046] Organic-inorganic hybrid (meth)acrylate obtained by
condensing colloidal silica with, for instance, (meth)acryloyloxy
alkoxysilane is also used for raising, for example, the hardness of
the coating. Examples therefor are an organic-inorganic hybrid
vinyl compound or an organic-inorganic hybrid (meth)acrylate
compound containing a combination of, for instance, colloidal
silica with any one selected from: vinyltrimethoxysilane,
vinyltriethoxysilane, p-styryltrimethoxysilane, 3-(meth)acryloxy
propyl methyldimethoxy silane, 3-(meth)acryloxy propyl
trimethoxysilane, 2-(meth)acryloxy ethyl trimethoxysilane,
2-(meth)acryloxy ethyl triethoxysilane, 3-(meth)acryloxy
propylmethyl diethoxysilane and 3-(meth)acryloxy propyl
triethoxysilane.
[0047] Among the above compounds, in view of dynamics
characteristics of the cured product after the curing with active
energy or the like, the preferable compositions are monofunctional
(meth)acrylate or polyfunctional (meth)acrylate having
polymerizable unsaturated bond. Monofunctional (meth)acrylate is
more preferable. Further, in view of the transparency of the
obtained polymer, methyl methacrylate is particularly
preferable.
[0048] The content of the monomer (B) in the monomer component is
65 to 99.99 mol %, more preferably 80 to 99.9 mol %. When the
content of the monomer (B) is 65 mol % or more, the cured coating
film has sufficient weather resistance and transparency. When the
content of the monomer (B) is 99.99 mol % or less, the insufficient
curing of the coating is suppressed. As the result, the toughness,
heat resistance and wear resistance of the cured coating film are
enhanced.
[0049] The monomer for the monomer (B) may be made of a single one
of the above materials or a combination of two or more of the above
materials.
[0050] Further, in view of the dynamics characteristics,
transparency and weather resistance of the cured product after the
curing, the monomer (B) preferably contains methyl methacrylate at
the content of 50 mol % or more of the entire monomer (B), and the
content is more preferably 60 to 100 mol %. When the content of
methyl methacrylate is 60 mol % or more, the cured coating film has
more sufficient weather resistance and transparency. When the
content of methyl methacrylate is 99.9 mol % or less, the
insufficient curing of the coating is further suppressed. As the
result, the toughness, heat resistance and wear resistance of the
cured coating film are further enhanced.
[0051] <Monomer (C)>
[0052] The curable composition according to the invention may
further contain, in addition to the monomer (A) and the monomer
(B), a polymer (C) containing a monomer (C) polymerizable with the
monomer (A). The monomer (C) is a polymerizable monomer other than
the monomer (A). The monomer (C) is not limited to a specific one
as long as it is polymerizable with the monomer (A). The monomer
(C) is preferably soluble in a mixture of the monomers (A) and (B).
Examples of the monomer (C) are those materials enumerated in the
description of the monomer (B). Among such materials, the monomer
(C) preferably contains the methyl methacrylate units at the
content of 50 mass % or more of the monomer (C).
[0053] The content of the polymer (C) is preferably 10 to 100 parts
by mass when the monomer component is 100 parts by mass, more
preferably 10 to 80 parts by mass.
[0054] The molecular weight of the polymer (C) is, but not limited
thereto, preferably in the range of 10,000 to 1,000,000, more
preferably 20,000 to 300,000 in terms of weight-average molecular
weight (Mw) because the polymer (C) can be easily mixed and
dissolved with the monomer.
[0055] The manufacturing method of the polymer (C) is not subject
to any limitation. The polymer (C) is preferably manufactured by
radical polymerization of the monomers. The monomers may be
polymerized in the presence of solvent, or the monomers alone may
be polymerized by mass polymerization.
[0056] When the polymer (C) is obtained by radical polymerization
of the monomers containing at least the monomer (A), the
polymerization temperature of the radical polymerization is
preferably 210.degree. C. or less. When the temperature is
210.degree. C. or less, the HALS skeleton is stably incorporated
into the cured product, and a transparent cured product is
obtained.
[0057] <Radical Polymerization Initiator (D)>
[0058] The curable composition according to the invention may
contain the radical polymerization initiator (D) as described
above. The radical polymerization initiator (D), which may be
suitably selected in view of the solubility of the initiator in the
curable composition, is not subject to any limitation.
[0059] Concrete examples of the radical polymerization initiator
(D) are preferably polymerization initiators activated by
irradiation of active energy rays, and among them photo
polymerization initiators are preferable. Examples of such radical
polymerization initiator (D) are carbonyl compounds such as
benzoin, benzoin monomethyl ether, benzoin isopropyl ether,
acetoin, benzyl, benzophenone, p-methoxybenzophenone,
diethoxyacetophenone, benzyl dimethyl ketal, 2,2-di
ethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, methyl
phenyl glyoxylate, and 2-hydroxy-2-methyl-1-phenylpropane-1-on;
sulfur compounds such as tetramethyl thiuram monosulphide and
tetramethyl thiuram disulphide; phosphorus compounds such as
2,4,6-trimethylbenzoil diphenylphosphine oxide,
2,4,6-trimethylbenzoil phenyl ethoxy phosphine oxide,
bis(2,4,6-trimethyl benzoil)-phenyl phosphine oxide and bis
(2,6-dimethoxy benzoil)-2,4,4-trimethyl-pentylphosphine oxide;
2-benzyl-2-dimethylamino-1-(4-morpholino phenyl) butanone-1; or
camphorquinone. These inhibitors may be used alone or in
combination of two or more of them. These photo polymerization
initiators may be optionally combined according to the required
film performance.
[0060] The content of the radical polymerization initiator (D) is
preferably in the range of 0.1 to 10 parts by mass when the summed
amount of the monomer (A) and the monomer (B) is 100 parts by mass,
more preferably in the range of 0.2 to 6 parts by mass. When the
content of the radical polymerization initiator (D) is 0.1 parts by
mass or more, the curing speed of the coated cured product tends to
be sufficiently increased. As the result, the obtained cured
coating film tends to have excellent hardness (wear resistance) and
weather resistance, and tends to be closely attached to the
substrate. When the content of the radical polymerization initiator
(D) is 10 parts by mass or less, the coloring of the cured coating
film and the reduction in the weather resistance thereof are
prevented.
[0061] <Ultraviolet Absorber (E)>
[0062] The curable composition according to the invention may
contain an ultraviolet absorber (E). The ultraviolet absorber (E)
is, but not limited thereto. The ultraviolet absorber (E) is
preferably selected in the light of its uniform solubility ability
of facilitating curing by active energy rays, and ability of
providing the obtained cured product with the desired weather
resistance. Ultraviolet absorbers particularly preferable for the
ultraviolet absorber (E) are compounds: that are derived from
materials based on benzophenone, benzotriazole, phenyl salicylate,
phenyl benzoate or hydroxyphenyl triazine; and whose wavelength of
maximum absorption is in the range of 240 to 380 nm. In particular,
benzophenone-based ultraviolet absorbers, benzotriazole-based
ultraviolet absorbers and hydroxyphenyl triazine-based ultraviolet
absorbers are preferable for the ultraviolet absorber (E). Further,
a combination of two or more of the above compounds in use is the
most preferable.
[0063] Among the above compounds, preferably, concrete examples of
the ultraviolet absorber (E) are 2-hydroxy-4-octoxybenzophenone and
2,4-dihydroxy benzophenone (i.e., benzophenone-based materials),
2-(2-hydroxy-tert-butylphenyl) benzotriazole (i.e.,
benzotriazole-based material), and
2-[4-(octyl-2-methylethanoate)oxy-2-hydroxyphenyl]-4,6-[bis(2,4-dimethylp-
henyl)]-1,3,5-triazine (i.e., hydroxyphenyl triazine-based
material). A combination of two or more of the above in use is more
preferable. The content of the ultraviolet absorber (E) is
preferably 0.01 to 10 parts by mass when the summed amount of the
monomer (A) and the monomer (B) is 100 parts by mass, more
preferably 0.05 to 1 parts by mass. When the content of the
ultraviolet absorber (E) is 2 parts by mass or more, the cured
coating film has sufficient weather resistance. When the content of
the ultraviolet absorber (E) is 30 parts by mass or less, the
insufficient curing of the coating is further suppressed. Further,
the hardness, heat resistance and wear resistance of the cured
coating film are not reduced.
[0064] The curable composition preferably contains the above
components (A), (B) and (D) as the primary components, and may
further preferably contain the component (E).
[0065] If required, the curable composition may further contain a
variety of additives such as organic solvent, antioxidant, yellow
turning inhibitor, bluing agent, colorant, leveling agent,
antifoaming agent, thickener, antisettling agent, antistatic agent,
and surfactant. The antioxidant may be a phenol-based antioxidant
such as IRGANOX 1010, IRGANOX 1076 or IRGANOX 1035 (each
manufactured by BASF Ltd. (previously known as CIBA Limited)),
sulfur-based antioxidant such as SUMILIZER TP-D (manufactured by
Sumitomo Chemical Company, Limited) or Adekastab AO series
(manufactured by ADEKA Corporation) or phosphorus-based
antioxidant. The organic solvent is suitably selected according to
the coating method. Specifically, when the curable composition is
applied to spray coating, the organic solvent is preferably a
suitable combination of alcohol-based solvent such as isobutanol,
ester-based solvent such as n-butyl acetate, ketone-based solvent
such as methyl isobutyl ketone and aromatic-based solvent such as
toluene. Further, the active energy ray-curable composition
(hereinafter also referred to as a coating material) preferably has
a viscosity of 20 mPas or less. When the curable composition is
used in coating such as shower flow coating or dip coating, the
viscosity of the coating material is preferably set at 100 mPas or
less. On the other hand, when the curable composition is used in a
high-solid coating material having a solid content of more than 80
mass %, it is desired that the solvent for the curable composition
be suitably selected in the view of the solubility of the additives
such as ultraviolet absorbers.
[0066] <Polymerization>
[0067] Polymerization of the curable composition is not subject to
any limitation. In polymerizing the curable composition, active
energy ray is usable. Examples of the active energy ray are X-ray,
ultraviolet and electron ray. The active energy ray is preferably
ultraviolet.
[0068] Ultraviolet is irradiated by a variety of ultraviolet
irradiators. Examples of the irradiating source are high-pressure
mercury lamps, low-pressure mercury lamps, metal-halide lamps,
Xenon lamps, chemical lamps, bacterial lamps, black lighting
devices and ultraviolet LEDs.
[0069] The irradiation intensity of the active energy ray is
suitably determined based on the relationship between the
concentration of the polymerization initiator contained in the
curable composition and dissolvable by active energy rays and the
irradiation time. Further, in the above polymerizable liquid
polymerizable with the active energy ray, the irradiation intensity
is preferably in the range of 1 mW/cm.sup.2 to 30 mw/cm.sup.2, in
view of the monomer growth speed. Too low irradiation intensity is
not preferable. Specifically, when the irradiation intensity is too
low, the polymerization initiator may not sufficiently dissolve,
and the polymerization speed may be decreased. On the other hand,
too high irradiation intensity is not preferable. Specifically,
when the irradiation intensity is too high, no matter how much the
initiator is increased, the monomer growth speed is not
sufficiently increased in the polymerizable liquid polymerizable
with active energy rays according to this method. Thus, much of the
initiator is consumed in the termination reaction. When the
irradiation intensity is too high, the reduction in the molecular
amount of the product sheet and the excessive irradiation of active
energy rays may cause the product to turn yellow.
[0070] The curable composition is polymerized into a cured coating
film by irradiation with active energy rays after being applied to
a substrate, a plastic product. Examples of the plastic are
preferably a variety of thermoplastic resins and heat curing
resins. These resins have been thus far demanded to, for instance,
improve their weather resistance. Examples of the thermoplastic
resins and heat curing resins are polymethyl methacryl resins,
polycarbonate resins, polyester resins, poly(polyester) carbonate
resins, polystylene resins, ABS resins, AS resins, polyamide
resins, polyarylate resins, polymethacrylimide resins, polyallyl
diglycol carbonate resins, polyolefin resins and amorphous
polyolefin resins. In particular, polymethyl methacryl resins,
polycarbonate resins, polystylene resins, polymethacrylimide resins
and amorphous polyolefin resins are excellent in transparency, and
improvement of the wear resistance in these resins has been
strongly demanded. Accordingly, the coating composition according
to the invention is effectively applicable to these resins in
particular. When the coating material is cured with the irradiation
of the active energy ray, the coating composition is applied to the
substrate to have a predetermined thickness, and the solvent is
thereafter volatilized. Then, using, for instance, a high pressure
mercury lamp or metal-halide lamp, ultraviolet or electron ray is
irradiated. The atmosphere under which the irradiation is conducted
may be air atmosphere or may be atmosphere of inert gas such as
nitrogen or argon.
[0071] The polymer obtained by polymerizing the curable
compositions according to the invention may be added as a light
stabilizer to a polymerizable composition intended to be used
outdoor in particular. Such a polymerizable composition is mainly
applicable to the exterior of automobile headlamp lenses and
vehicle sensors. The exterior substrate of the headlamp lenses or
the vehicle sensors are made of polycarbonate. Polycarbonate has
high impact resistance, heat resistance, transparency and
lightness. Therefore, polycarbonate is used as the material for
headlamp lenses or vehicle sensors. However, polycarbonate may not
have characteristics such as chemical resistance, weather
resistance and excoriation resistance. Thus, polycarbonate is
preferably applied with a coating material containing the polymer
obtained by polymerizing the curable composition according to the
invention. In other words, the polymerizable composition contains
at least the polymer obtained by polymerizing the curable
composition according to the invention and the polymerizable
monomers.
[0072] The curable composition according to the invention is
applicable as a coating material. Polycarbonate whose surface is
applied with the coating material formed of the polymer obtained
from the curable composition according to the invention has the
characteristics comparative to glass, and is light in weight and
easy to mold. Therefore, the polycarbonate whose surface is applied
with the coating material is favorably applicable not only to
automobile headlamp lenses and vehicle sensors but also in other
fields. The polycarbonate whose surface is applied with the coating
material is widely applicable to, for instance, outdoor signs,
greenhouses, window glasses of outdoor buildings, roofs and
balconies of terraces and garage and gauge covers.
[0073] Besides the above usage, the curable composition may be
applied to a variety of resin sheets or resin films to have a
predetermined thickness. After being applied thereto, the solvent
is volatilized, and then irradiated by, for example, ultraviolet or
electron rays using a high pressure mercury lamp or metal-halide
lamp. The atmosphere under which the irradiation is conducted may
be air atmosphere or may be atmosphere of inert gas such as
nitrogen or argon.
[0074] The polymer obtained from the curable composition according
to the invention is also applicable as resin sheets.
[0075] When the resin sheets are manufactured from the curable
composition according to the invention, the content of the methyl
methacrylate unit in the obtained polymer is preferably 50 mol % or
more. In the above, the curable composition preferably uses
polymethyl methacrylate as the polymer (C) described above, in view
of the optical characteristics.
[0076] The polymer used according to the invention preferably has a
weight-average molecular weight Mw of 30,000 to 500,000. When the
polymer has the weight-average molecular weight of 30,000 or more,
the heat resistance of the manufactured products is further
enhanced. On the other hand, when the polymer has the
weight-average molecular weight of 500,000 or less, the time for
dissolving various components into the polymer during the
preparation of the curable composition is shortened.
[0077] The curable composition preferably has a viscosity of 5000
mPas or more, more preferably 10000 mPas or more at 20.degree. C.
With this configuration, when the curable composition is fed to an
endless belt, the curable composition is formed into products
having a predetermined thickness. Alternatively, by covering either
surface of the composition with a material having low rigidity
(e.g., film), the surface of the composition has favorable outer
appearance.
[0078] The method of feeding the curable composition to the endless
belt is not subject to any limitation. Examples of the methods are
a method to feed the composition through a typical piping or hose,
and a variety of coating methods. The curable composition is fed to
the endless belt and formed into continuous sheet. Accordingly, the
curable composition is preferably fed by a feeding die to form a
sheet shape. Examples of the method to form the curable composition
into sheet shape are a method of feeding the curable composition
via the feeding die as described above, and a method of spreading
the curable composition fed to the endless belt using a roll and a
roll mediated by the endless belt. In addition, the above methods
may be combined to form the curable compositions into sheet
shape.
[0079] The material of the belt in use is not limited to a specific
one. The material may be freely selected (e.g., a metal or a
resin), as long as the belt holds the curable composition. In order
to manufacture the resin sheet in a continuous form, the belt is
preferably an endless belt. Since the polymerization and curing of
the composition involves polymerization shrinkage, the endless belt
is more preferably a metal endless belt having high rigidity. In
view of corrosion of the monomers, the endless belt is further
preferably a stainless endless belt. The surface of the resin sheet
transcribes the surface of the endless belt. Therefore, the endless
belt is the most preferably a stainless endless belt whose surface
is processed with mirror finishing.
[0080] The curable composition fed to the belt is covered with
active energy ray-transmissive film.
[0081] The active energy ray-transmissive film in use is made of a
transparent flexible synthetic resin film. The active energy
ray-transmissive film is preferably made of film deformed at
100.degree. C. or more to prevent the film from being deformed by
heat during the polymerization. Examples of the film are film of
synthetic resin such as polyethylene telephthalate, polyethylene
naphthalate or polycarbonate. Among the above materials,
polyethylene telephthalate film is preferably usable, in view of
its high permeability of the active energy ray and its high surface
texture. In view of the rigidity, the thickness of the film is
preferably 10 .mu.m or more, more preferably 50 .mu.m or more. In
view of the cost, the thickness is preferably 300 .mu.m or less,
more preferably 200 .mu.m or less.
[0082] The surface of the active energy ray-transmissive film in
contact with the active energy ray-curable composition is
transcribed in the surface of the resin sheet obtained as the
product. Therefore, the surface roughness (Ra) provided in JIS
B0601 is preferably 100 nm or less, more preferably 10 nm or
less.
[0083] The width of the active energy ray-transmissive film is set
to be equal to or more than the width of the active energy
ray-curable composition spread on the belt. The "width" herein
means the length extending in the direction perpendicular to the
direction in which the belt is transported.
[0084] The widthwise ends of the active energy ray-transmissive
film are preferably both attached to the belt by adhesive tapes.
With this configuration, the active energy ray-transmissive film
serves similarly to a gasket. In other words, by closing the both
ends of the active energy ray-transmissive film, the active energy
ray-curable composition is prevented from leaking through the
ends.
[0085] The adhesive tapes to be used are not subject to any
limitations, as long as the adhesive tapes close the ends. The
width of the adhesive tapes may be suitably determined. Examples of
the material for the adhesive tapes are polyester-based resin such
as PET, polyolefin-based resin such as polypropylene,
polyimide-based resin, fluorine-based resin such as PTFE, cloth
such as cotton cloth, staple fiber and non-woven textile fabrics,
and aluminum foil. Examples of the adhesive for use in the adhesive
tapes are acryl-based adhesive, silicone-based adhesive or
rubber-based adhesive. The adhesive tapes may be one-sided adhesive
tapes or double-sided adhesive tapes. When the ends are closed
using one-sided adhesive tapes, such one-sided adhesive tapes are
exemplarily attached as illustrated in FIG. 1. When the ends are
closed using double-sided adhesive tapes, such double-sided
adhesive tapes are exemplarily attached as illustrated in FIG.
2.
[0086] When one-sided adhesive tapes are utilized, the widthwise
ends of the active energy ray-transmissive film each are preferably
located at positions interior with respect to the widthwise ends of
the belt, spaced apart respectively from the widthwise ends of the
belt by 5 mm or more. With this configuration, the tapes are easily
attached.
[0087] When the adhesive tapes are removed from the belt, the belt
is preferably free from adhesive of the adhesive tapes. More
preferably, the adhesive of the adhesive tapes does not remain on
the belt when the adhesive tapes are removed from the belt after
the adhesive tapes are heat-treated under the condition 1 described
below. Further preferably, the adhesive of the adhesive tapes does
not remain on the belt when the adhesive tapes are removed from the
belt after the adhesive tapes are heat-treated under the condition
2 described below. With this configuration, contamination during
the manufacturing process is prevented. Alternatively, the belt is
prevented from having adhesive residual spots formed by repeatedly
attaching the tapes to the belt.
[0088] Condition 1: heat treatment under the atmosphere of
100.degree. C. for 20 minutes
[0089] Condition 2: heat treatment under the atmosphere of
150.degree. C. for 10 minutes
[0090] Examples of the adhesive tapes that do not leave their
adhesive on the belt after being heat-treated under the above
condition 1 are No. 31B manufactured by Nitto Denko Corporation,
No. 644 manufactured by Teraoka Seisakusho Co., Ltd., and No. 754
and No. 4734 manufactured by Sumitomo 3M Limited. Further, examples
of the adhesive tapes that do not leave their adhesive on the belt
after being heat-treated under the above condition 2 are No. 609
manufactured by Teraoka Seisakusho Co., Ltd., No. 923UL
manufactured by Nitto Denko Corporation, and No. 5434 manufactured
by Sumitomo 3M Limited.
[0091] The transportation speed of the belt is preferably 0.5 to 15
m/min, more preferably 1 to 10 m/min. Too low speed is not
preferable. Specifically, when the speed is too low, the production
amount of the resin sheet obtained as the products may be reduced.
Too high speed is not preferable. Specifically, when the speed is
too high, the section irradiated with the active energy ray for
obtaining the time for polymerization may be increased.
[0092] The temperature condition during the curing may be suitably
determined based on, for instance, the polymerization speed or the
viscosity condition. However, the temperature when the active
energy ray is irradiated is preferably the boiling point of the
polymerizable monomer or less. For instance, when methyl
methacrylate is used, the temperature is preferably 100.degree. C.
or less. In addition, it is known that when methyl methacrylate is
contained, the lower the temperature during the polymerization is,
the more the syndiotactic component is increased by the location of
the bonds between the polymerizable monomer units in the polymer.
The more the syndiotactic component is, the higher the glass
transition temperature Tg of the polymer tends to be, which leads
to higher heat resistance. Accordingly, the polymerization
temperature when the active energy ray is irradiated is more
preferably 50.degree. C. or less. With this configuration, the heat
resistance is enhanced.
[0093] The resin cured with the irradiation of the active energy
ray may be further suitably subjected to a heat treatment at a
temperature equal to or more than the glass transition temperature
Tg obtained by the combination of the polymerizable monomer in use
and the obtained polymer. With this configuration, the amount of
the residue polymerizable monomers is reducible. When methyl
methacrylate is used, the heat treatment is preferably conducted at
100.degree. C. or more.
[0094] The thickness of the resin sheet is not specifically
limited, but it is preferably 0.01 mm or more and 5 mm or less,
more preferably 0.1 mm or more and 5 mm or less. When the thickness
of the resin sheet is 5 mm or less, polymerization heat is easily
eliminated. With this configuration, boiling of the non-polymerized
monomers and the foaming within the resin sheets caused by such
boiling are prevented. When the thickness of the resin sheet is
0.01 mm or more, the sheet is easily handled, and the advantageous
effects of the invention are easily obtained.
[0095] The cured coating film or the resin sheet obtained from the
curable composition according to the invention is excellent in
transparency. The total light transmittance of the cured coating
film or the resin sheet obtained by curing the curable composition
is preferably 85 to 100%, more preferably 90 to 100%. The haze
value thereof is preferably 5% or less, more preferably less than
5%. The cured coating film obtained from the curable composition
according to the invention has reduced yellowness. The yellowness
of the cured coating film is preferably 10 or less, more preferably
5 or less.
EXAMPLES
[0096] In the following description, the invention will be
described further in details, by describing synthesis examples,
examples and Comparative Examples. The invention is not
specifically limited to such synthesis examples or examples.
[0097] In the following description, the formulation and number
average molecular weight of the polymers synthesized in the
synthesis examples, examples, and comparative examples were
evaluated by the following method.
[0098] In the description of the examples, the "parts" and "%"
respectively mean "parts by mass" and "mass %."
(1) Identification of Monomer (A)
[0099] Identification of the monomer (A) structure was conducted
using 1H-NMR JNM-EX270 (a product name, manufactured by JEOL
Ltd.).
[0100] The monomer (A) was dissolved in deuterated chloroform. The
compound was identified based on the peak integrated intensity and
the peak position. The measurement temperature was 25.degree. C.,
and the cumulative number was 16.
(2) Polymerization Conversion
[0101] The polymerization conversion of the monomer component was
identified using 1H-NMR JNM-EX270 (a product name, manufactured by
JEOL Ltd.).
[0102] In the copolymerization of the monomer (A) and methyl
methacrylate, the polymerization conversion was calculated based on
the integral ratio between: the peak attributed to the hydrogen in
the alkoxyl group originating from the monomer and the polymer; and
the peak attributed to the hydrogen in the C--C double bonds
originating from the monomer.
(3) Outer Appearance (Coloring)
[0103] By visually observing the product, whether or not the
product was colored was determined.
(4) Weather Resistance Test
[0104] The product was cut into a size of 40 mm.times.40 mm. After
the surface of the product was cleaned with neutral detergent, a
weather resistance test was conducted using a Metal Weather
KU-R5N-A (manufactured by Daipla Wintes Co., Ltd.) with an
irradiation intensity of 80 mW/cm.sup.2 at a temperature of
63.degree. C. for 344 hours.
[0105] The total light transmittance and haze value of the product
were measured using a Haze Meter HM-65W Type (manufactured by
Murakami Color Research Laboratory Co., Ltd.) according to the
method described in JIS-K7105.
[0106] Yellowness was measured by measuring the transmission
spectrums before and after the weather resistance test using a
spectrophotometer MCPD-3000 (manufactured by Otsuka Electronics
Co., Ltd.). The measured values were corrected according to the
following formula, based on the thickness of the sample.
Yellowness (corrected value)=Yellowness (measured value)/Plate
Thickness (mm)
[0107] In addition, a difference between the yellowness (corrected
value) before the weather resistance test and the yellowness
(corrected value) after the weather resistance test was obtained,
and the difference was then used as the displacement of the
yellowness.
(Synthesis Example 1) Synthesis of
1-octyloxy-2,2,6,6-tetramethyl-4-methacryloyloxy Piperidine
(Monomer (A-1))
[0108] A solution prepared by dissolving 30.3 g (330 mmol) of
triethylamine and 34.4 g (200 mmol) of
4-hydroxy-2,2,6,6-tetramethyl piperidine-N-oxide (TEMPOL) in 200 ml
of tetrahydrofuran (THF) was added with 25.5 g (250 mmol) of acetic
anhydride at 0.degree. C.
[0109] The solution was warmed up to 25.degree. C. and left for
reaction for 12 hours, and concentrated using a rotary evaporator.
The residue was put into 1 litter of iced water. By filtering the
precipitated orange solid, 33.8 g of
4-acetyloxy-2,2,6,6-tetramethyl piperidine-N-oxide was
obtained.
[0110] In 200 ml of octane, 21.4 g (100 mmol) of
4-acetyloxy-2,2,6,6-tetramethyl piperidine-N-oxide was dissolved.
Subsequently, 0.9 g (6 mmol) of molybdenum oxide (VI) was added to
the resulting solution, and the solution was then dehydrated by
heating under reflux. While the solution was being dehydrated by
azeotropy, 19.2 g (150 mmol) of the 70% t-butyl hydroperoxide
aqueous solution was dropped therein for 9 hours, and left so that
reactions took place. Then, the solution was cooled to room
temperature. Subsequently, by gradually adding 30 ml of saturated
aqueous solution of sodium bisulphites thereto, non-reacted
peroxides were deactivated. The organic layers were concentrated
using a rotary evaporator. Then, the residue was dissolved in 100
ml of ethanol, added with 6.7 g (150 mmol) of potassium hydroxide,
and left for reaction at 25.degree. C. for 2 hours.
[0111] The mixture was concentrated using a rotary evaporator.
Then, 200 ml of water was added to the residue, and extraction was
conducted using 200 ml of dichloromethane in total. After the
organic layers were concentrated using a rotary evaporator, the
organic layers were dissolved in 20 ml of dichloromethane and 10 ml
of triethylamine. The solution was added with 10.5 g (100 mmol) of
methacryloyl chloride at 0.degree. C., and left for reaction for 1
hour. The mixture was concentrated using a rotary evaporator. Then,
200 ml of water was added to the residue, and extraction was
conducted using 200 ml of acetic ether in total. The organic layers
were concentrated using a rotary evaporator. The residue was
refined by column chromatography (silica gel, hexane/acetic
ether=20/1 in volume ratio). With this operation, 26.3 g of
colorless liquid was obtained (the yield was 74.4%).
[0112] By 1H-NMR measurement, the obtained product was identified
as the monomer (A-1) represented by the formula (101) as
follows.
[0113] 1H-NMR (CDCl.sub.3): .delta. (ppm): 0.89 (m, 6H), 1.17 (m,
10H), 1.18 (s, 6H), 1.21 (s, 6H), 1.61 (m, 2H), 1.85 (m, 2H), 1.92
(s, 3H), 3.60-3.93 (m, 1H), 5.07 (m, 1H), 5.53 (s, 1H), 6.03 (s,
1H)
##STR00007##
[0114] In the formula, Oc represents any one of the structures
represented by the following formulae (I) to (III). In the
following description, the structures represented by the following
formulae (I) to (III) will be referred to as "Oc."
##STR00008##
(Synthesis Example 2) Synthesis of
1-propyloxy-2,2,6,6-tetramethyl-4-methacryloyloxy Piperidine
(Monomer (A-2))
[0115] A solution prepared by dissolving 48.6 g (480 mmol) of
triethylamine and 68.9 g (400 mmol) of
4-hydroxy-2,2,6,6-tetramethyl piperidine-N-oxide (TEMPOL) in 100 ml
of dichloromethane was added with 47.8 g (440 mmol) of
trimethylsilyl chloride at 0.degree. C.
[0116] The solution was warmed up to 25.degree. C. and left for
reaction for 2 hours. Then, the solution was concentrated using a
rotary evaporator. 500 ml of water was added to the residue, and
extraction was conducted using 500 ml of acetic ether in total. The
organic layers were concentrated using a rotary evaporator, and the
residue was dissolved in hexane. By recrystallization, 96.2 g of
4-trimethylsilyloxy-2,2,6,6-tetramethyl piperidine-N-oxide was
obtained.
[0117] 4.6 g (190 mmol) of chipped magnesium, 100 ml of dehydrated
THE and 10 mg of iodine were put into the reaction container. The
atmosphere in the container was replaced with argon. Subsequently,
23.4 g (190 mmol) of 1-bromopropane was dropped into the container
while the temperature within the container was kept at 55.degree.
C. to 65.degree. C., and Grignard reactant was prepared.
[0118] In another reaction container, 96.2 g (394 mmol) of
4-trimethylsilyloxy-2,2,2,6-tetramethyl piperidine-N-oxide was
dissolved in 100 ml of dehydrated THF. The prepared Grignard
reactant was dropped thereinto at 0.degree. C. After being left for
reaction for 3 hours, the solution was concentrated using a rotary
evaporator. 500 ml of water was added to the residue, and
extraction was conducted using 500 ml of acetic ether in total. The
organic layers were concentrated using a rotary evaporator. The
residue was refined by column chromatography (silica gel,
hexane/acetic ether=20/1 in volume ratio), and 38.5 g of
1-(1-propyl)oxy-2,2,6,6-tetramethyl-4-trimethylsilyloxy piperidine
was obtained.
[0119] 38.5 g of
1-(1-propyl)oxy-2,2,6,6-tetramethyl-4-trimethylsilyloxy piperidine
was dissolved in 300 ml of methanol. The solution was added with
0.14 g (0.1 mmol) of potassium carbonate and left for reaction for
3 hours. Then, the solution was concentrated using a rotary
evaporator. 300 ml of water was added to the residue, and
extraction was conducted using 300 ml of acetic ether in total. The
organic layers were concentrated using a rotary evaporator. The
residue was dissolved in 20 ml of dichloromethane and 20 ml of
triethylamine. The solution was added with 14.1 g (135 mmol) of
methacryloyl chloride at 0.degree. C. After the solution was left
for reaction for 1 hour, the precipitated triethylamine
hydrochloride was filtered. The solution was concentrated using a
rotary evaporator. The residue was refined by column chromatography
(silica gel, hexane/acetic ether=20/1 in volume ratio), and 29.7 g
of colorless liquid was obtained (the yield was 26.2%).
[0120] By 1H-NMR measurement, the obtained product was identified
as the monomer (A-2) represented by the formula (102) as
follows.
[0121] 1H-NM (CDCl.sub.3): .delta. (ppm): 0.94 (t, 3H), 1.21 (s,
12H), 1.53 (m, 2H), 1.61 (m, 2H), 1.86 (m, 2H), 1.92 (s, 3H), 3.70
(t, 2H), 5.07 (m, 1H), 5.53 (s, 1H), 6.06 (s, 1H)
##STR00009##
(Synthesis Example 3) Synthesis of
1-octyloxy-2,2,6,6-tetramethyl-4-(2-(2-methacryloyloxy) ethoxy)
ethoxy Piperidine (Monomer (A-3))
[0122] 17.8 g (100 mmol) of 2,2,6,6-tetramethyl-4-hydroxy
piperidine-N-oxide was dissolved in 100 ml of acetone. 34 g (300
mmol) of 30% hydrogen peroxide aqueous solution was slowly added
thereto for 10 minutes or more. While the solution was cooled to
5.degree. C., 0.49 g (5.0 mol %) of copper chloride (I) was added
thereto. The temperature of the reaction mixture was kept at
5.degree. C. to 55.degree. C. In 15 minutes later, 0.5 g of 35%
acidum hydrochloricum was added thereto, and the reaction mixture
was stirred for 2 hours at the room temperature. In 2 hours later,
the reaction mixture was added with 50 ml of sodium bisulfite
aqueous solution (4 mol/L) and 100 ml of saturated aqueous solution
of potassium bicarbonate, and extraction was conducted using 300 ml
of acetic ether. By concentrating the organic layers using a rotary
evaporator, 1-methyloxy-2,2,6,6-tetramethyl-4-hydroxy piperidine
was obtained.
[0123] The obtained 1-methyloxy-2,2,6,6-tetramethyl-4-hydroxy
piperidine was dissolved in 50 ml of dichloromethane and 50 ml of
triethylamine. The solution was slowly added with 10.4 g (100 mmol)
of methacryloyl chloride at 0.degree. C. The solution was gradually
warmed up to the room temperature and left for reaction for 1 hour.
In 1 hour later, the reaction mixture was concentrated using a
rotary evaporator. 300 ml of water was added to the residue, and
extraction was conducted using 300 ml of acetic ether. The organic
layers were concentrated using a rotary evaporator. The residue was
refined by column chromatography (silica gel, hexane/acetic
ether=10/1 in volume ratio), and 19.0 g of colorless liquid was
obtained (the yield was 74.3%).
[0124] By 1H-NMR measurement, the obtained product was identified
as the monomer (A-3) represented by the formula (103) as
follows.
[0125] 1H-NMR (CDCl.sub.3): .delta. (ppm): 0.89 (m, 6H), 1.15 (s,
6H), 1.18 (s, 6H), 1.29 (m, 10H), 1.30-1.41 (m, 2H), 1.59-1.82 (m,
2H), 1.95 (s, 3H), 2.62 (m, 4H), 3.73 (m, 1H), 4.35 (s, 4H), 5.02
(m, 1H), 5.60 (s, 1H), 6.13 (s, 1H)
##STR00010##
(Synthesis Example 4) Synthesis of
1-octyloxy-2,2,6,6-tetramethyl-4-(4-(2-methacryloyloxy) ethoxy-1,
4-dioxo)butoxy Piperidine (Monomer (A-4))
[0126] A solution prepared by dissolving 20.2 g (200 mmol) of
triethylamine and 26.0 g (100 mmol) of
2,2,6,6-tetramethyl-4-(2-(2-hydroxy) ethoxy) ethoxy piperidine in
100 ml of THF was added with 12.3 g (120 mmol) of acetic anhydride
at 0.degree. C.
[0127] The solution was warmed up to 25.degree. C. and left for
reaction for 12 hours. Then, the solution was concentrated using a
rotary evaporator. 500 ml of water was added to the residue, and
extraction was conducted using 500 ml of acetic ether in total. The
organic layers were concentrated using a rotary evaporator. The
residue was refined by column chromatography (silica gel,
hexane/acetic ether=1/1 in volume ratio), and 5.6 g (22 mmol) of
2,2,6,6-tetramethyl-4-(2-(2-acetyloxy) ethoxy) ethoxy piperidine
was obtained.
[0128] In 100 ml of octane, 3.0 g (10 mmol) of
2,2,6,6-tetramethyl-4-(2-(2-acetyloxy) ethoxy) ethoxy piperidine
was dissolved. After being added with 0.07 g (0.5 mmol) of
molybdenum oxide (VI), the solution was dehydrated by heating under
reflux. While the solution was being dehydrated by azeotropy, 12.8
g (100 mmol) of the 70% t-butyl hydroperoxide aqueous solution was
dropped therein for 6 hours, left so that reactions took place.
Then, the solution was cooled to the room temperature.
Subsequently, by gradually adding 20 ml of saturated aqueous
solution of sodium bisulphites thereto, non-reacted peroxides were
deactivated. The organic layers were concentrated using a rotary
evaporator. Then, the residue was dissolved in 15 ml of ethanol.
The solution was added with 0.6 g (15 mmol) of sodium hydroxide,
and left for reaction for 2 hours at 25.degree. C.
[0129] The mixture was concentrated using a rotary evaporator. 100
ml of water was added to the residue, and extraction was conducted
using 100 ml of dichloromethane in total. The organic layers were
concentrated using a rotary evaporator. Then, the organic layers
were dissolved in 10 ml of triethylamine, and the solution was
added with 1.1 g (10 mmol) of methacryloyl chloride at 0.degree.
C., and left for reaction for 1 hour. The mixture was concentrated
using a rotary evaporator. 50 ml of water was added to the residue,
and extraction was conducted using 50 ml of acetic ether in total.
The organic layers were concentrated using a rotary evaporator. The
residue was refined by column chromatography (silica gel,
hexane/acetic ether=3/1 in volume ratio), and 1.9 g (3.1 mmol) of
colorless liquid was obtained (the yield was 3.1%).
[0130] By 1H-NMR measurement, the obtained product was identified
as the vinyl monomer (A-4) represented by the formula (104) as
follows.
[0131] 1H-NMR (CDCl.sub.3): .delta. (ppm): 0.89 (m, 6H), 1.14 (s,
12H), 1.28 (m, 10H), 1.35-1.47 (m, 2H), 1.63-1.84 (m, 2H), 1.95 (s,
3H), 3.54-3.87 (m, 2H), 3.61 (m, 4H), 3.75 (t, 2H), 4.30 (t, 2H),
5.57 (s, 1H), 6.14 (s, 1H)
##STR00011##
(Synthesis Example 5) Synthesis of
1-methyloxy-2,2,6,6-tetramethyl-4-methacryloyloxy Piperidine
(Monomer (A-5))
[0132] In 100 ml of octane, 6.4 g (30 mmol) of
4-acetyloxy-2,2,6,6-tetramethyl piperidine-N-oxide, which was
synthesized according to the method described in Synthesis Example
1 above, was dissolved. After being added with 0.1 g (0.7 mmol) of
molybdenum oxide (VI), the solution was dehydrated by heating under
reflux. While the solution was being dehydrated by azeotropy, 12.8
g (100 mmol) of the 70% t-butyl hydroperoxide aqueous solution was
dropped therein for 6 hours, left so that reactions took place.
Then, the solution was cooled to the room temperature.
Subsequently, by gradually adding 50 ml of saturated aqueous
solution of sodium bisulphites thereto, non-reacted peroxides were
deactivated. The organic layers were concentrated using a rotary
evaporator. Then, the residue was dissolved in 50 ml of ethanol.
The solution was added with 2.8 g (50 mmol) of sodium hydroxide,
and left for reaction for 4 hours at 25.degree. C.
[0133] The mixture was concentrated using a rotary evaporator. 100
ml of water was added to the residue, and extraction was conducted
using 100 ml of dichloromethane in total. The organic layers were
concentrated using a rotary evaporator. The residue was added with
20 ml of tetrahydrofuran, 4.0 g (40 mmol) of triethylamine and 3.0
g (30 mmol) of succinic anhydride. The solution was stirred
continuously for 4 hours at 70.degree. C. In 4 hours later, the
solution was concentrated using a rotary evaporator. 100 ml of
saturated aqueous solution of ammonium chloride was added to the
residue, and extraction was conducted using 100 ml of acetic ether
in total.
[0134] The organic layers were concentrated using a rotary
evaporator. The residue was added with 3.9 g (30 mmol) of
2-hydroxyethyl methacrylate, 0.24 g (2 mmol) of N,
N'-dimethyl-4-aminopyridine and 5 ml of dichloromethane. A solution
prepared by dissolving 6.2 g (30 mmol) of N,
N'-dicyclohexylcarbodiimide in 20 ml of dichloromethane was dropped
thereinto at 0.degree. C., and left for reaction for 4 hours. In 4
hours later, the precipitated solid was filtered. The filtrate was
concentrated using a rotary evaporator. The residue was refined by
column chromatography (silica gel, hexane/acetic ether=5/1 in
volume ratio), and 5.58 g of colorless liquid was obtained (the
yield was 56.1%).
[0135] By 1H-NMR measurement, the obtained product was identified
as the vinyl monomer (A-5) represented by the formula (105) as
follows.
[0136] 1H-NMR (CDCl.sub.3): .delta. (ppm): 1.19 (s, 6H), 1.23 (s,
6H), 1.60 (m, 2H), 1.87 (m, 2H), 1.92 (s, 3H), 3.62 (s, 3H), 5.07
(m, 1H), 5.53 (s, 1H), 6.06 (s, 1H)
##STR00012##
Example 1
[0137] A monomer component was prepared by mixing 60 parts of
methyl methacrylate (MMA) with 0.35 parts of the monomer (A-1). The
resulting monomer component (100 mol %) contained 0.10 mol % of the
monomer (A-1).
[0138] To the monomer component, 0.30 parts of
1-hydroxycyclohexyl-phenyl ketone (IRGACURE 184 manufactured by
Ciba Specialty Chemicals Inc.) as a polymerization initiator and
0.05 parts of di(2-ethylhexyl) sodium sulfosuccinate (AEROSOL
OT-100 manufactured by Mitsui Cyanamid Ltd.) as a release agent
were added. The resulting mixture was then dissolved at normal
temperature. Subsequently, 40 parts of polymethylmethacrylate
(BR-83 manufactured by Mitsubishi Rayon Co., Ltd., 40,000 in
weight-average molecular weight) was heat-melted at 80.degree. C.
for 30 minutes to give the active energy ray-curable composition
(1). Subsequently, the resulting composition (1) was left at
50.degree. C. for 2 hours, and naturally cooled to normal
temperature.
[0139] Using apparatus similar to that the apparatus illustrated in
FIG. 1, resin sheets were manufactured. A stainless endless belt
having a width of 500 mm was used as an endless belt 3. A
ultraviolet transmissive film 5 was a polyethylene terephthalate
film of 450 mm in width and 188 .mu.m in thickness (COSMOSHINE
A4100 manufactured by Toyobo Co., Ltd.). A ultraviolet irradiator 4
was an FL30S-BL Lamp (product name) manufactured by Toshiba
Corporation. A pre-heating mechanism 9 and a post-heating mechanism
10 were hot-air heaters, respectively.
[0140] The transportation speed of the endless belt 3 was set at
1.5 m/min. The active energy ray-curable composition (1) was fed
from a feeding die 1 so that the composition (1) formed a sheet of
400 mm in width and 1 mm in thickness. The ultraviolet transmissive
film 5 was covered thereon. Then, with the pre-heating mechanism,
the composition was controlled to be 60.degree. C. before being
irradiated with the ultraviolet. Using the ultraviolet irradiator
4, ultraviolet was irradiated thereto for 10 minutes at an
irradiation intensity of 5 mW/cm.sup.2. The composition was then
heat treated by the post-heating mechanism 10 for 5 minutes at
130.degree. C. Thereafter, the composition was air-cooled to
90.degree. C., and the resin sheet was removed from the ultraviolet
transmissive film 5 and the endless belt 3.
[0141] The upper and lower surfaces of the obtained transparent
resin sheet (product (1)) were flat and smooth, and the product had
good outer appearance. The obtained transparent resin sheet had a
slightly reduced thickness at its edges, due to flux before the
irradiation of ultraviolet or the like.
[0142] The polymer conversion, outer appearance and yellowness (due
to the weather resistance test) of the product (1) are shown in
Table 1.
Examples 2 to 5
[0143] Products (2) to (5) were obtained through the same
operations as in Example 1 except that the types and amounts of the
monomer (A) were changed to those shown in Table 1. The polymer
conversion, outer appearance and yellowness (due to the weather
resistance test) of the products (2) to (5) are shown in Table
1.
Comparative Examples 1 to 4
[0144] Products (6) to (9) were obtained through the same
operations as in Example 1 except that: the monomer (A-1) was not
used. The HALS shown in Table 2 was used in the amount as shown in
Table 2). The polymer conversion, outer appearance and yellowness
(due to the weather resistance test) of the products (6) to (9) are
shown in Table 2.
Comparative Example 5
[0145] A product (10) was obtained through the same operations as
in Example 1 (except that the monomer (A-1) was not used). The
polymer conversion, outer appearance and yellowness (due to the
weather resistance test) of the product (10) are shown in Table
2.
TABLE-US-00001 TABLE 1 Total Light Transmittance Yellowness
(corrected) Monomer Outer [%] Haze (%) Weather Resistance Test MMA
(A) Conversion Appearance before after before after before after
Product [parts] [parts] [mol %] [%] [color] test test test test
test test displacement Example 1 1 60 A-1 0.35 0.10 99.3 colorless
92.2 91.8 0.35 0.39 0.22 1.02 0.80 Example 2 2 60 A-2 0.28 0.10
99.2 colorless 92.1 91.2 0.26 0.41 0.22 1.15 0.93 Example 3 3 60
A-3 0.21 0.10 99.4 colorless 92.2 91.8 0.59 0.65 0.20 1.19 0.99
Example 4 4 60 A-4 0.46 0.10 99.1 colorless 91.8 91.9 0.29 0.42
0.21 1.18 0.97 Example 5 5 60 A-5 0.49 0.10 99.2 colorless 91.8 --
0.48 -- 0.24 -- --
TABLE-US-00002 TABLE 2 Total Light Transmittance Yellowness
(corrected) Outer [%] Haze (%) Weather Resistance Test MMA HALS
Conversion Appearance before after before after before after dis-
Product [parts] [parts] [mol %] [%] [color] test test test test
test test placement Comparative 6 60 LA-87 0.23 0.10 99.3 colorless
91.9 90.2 0.52 0.96 0.23 1.43 1.20 Example 1 Comparative 7 60 LA-82
0.24 0.10 99.3 colorless 92.1 91.6 0.48 1.01 0.23 1.36 1.13 Example
2 Comparative 8 60 LS770 0.24 0.05* 99.3 colorless 92.3 91.2 0.48
1.03 0.21 1.47 1.26 Example 3 Comparative 9 60 TV-292 0.25 0.05*
99.3 colorless 92.0 91.8 0.65 1.02 0.23 1.33 1.10 Example 4
Comparative 10 60 -- -- -- 99.3 colorless 92.4 91.6 0.32 0.89 0.23
1.58 1.35 Example 5
Abbreviation in Tables:
[0146] LA-87: 2,2,6,6-tetramethyl-4-methacryloyloxy piperidine
(LA-87 manufactured by ADEKA Corporation)
[0147] LA-82: 1,2,2,6-pentamethyl-4-methacryloyloxy piperidine
(LA-82 manufactured by ADEKA Corporation)
[0148] LS770: bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate
(manufactured by ADEKA Corporation)
[0149] TV-292: bis(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate
(TV-292 manufactured by Ciba Japan K.K.)
[0150] LS 770 and TV-292 have hindered amine structures with
piperidine skeletons in their molecules (hereinafter referred to as
"HALS portions"). Thus, they were added as HALS portions in amount
of 0.10 mol %.
[0151] As is clear from Table 1, the product (Examples 1 to 5)
obtained from the manufacturing method according to the invention
had small yellowness displacement and favorable weather resistance.
Comparative Examples 1 to 5, which contained no monomer (A), had
great yellowness displacement and inferior weather resistance.
[0152] Next, cured coating films obtained from the manufacturing
method according to the invention will be described with reference
to examples and Comparative Examples, through which the invention
will be described in further detail. The invention is not limited
by such synthesis examples and examples.
Examples 6 to 15, Comparative Examples 6 to 10
Method of Forming Cured Coating Film Test Piece
[0153] Polycarbonate resin plates of 3 mm in thickness (product
name "Lexan LS-2" manufactured by General Electric Company) were
coated with the curable compositions composed as in Tables 3 and 4
by bar coating to give a cured coating film of 8 .mu.m in
thickness. The coated plates were heated in a heating furnace of
60.degree. C. for 90 seconds, and the organic solvents were
volatilized. Then, using a high-pressure mercury lamp in the air,
energy having a wavelength of 340 to 380 nm and a light integral of
3000 mJ/cm.sup.2 was irradiated to cure the curable compositions.
In this manner, products 11 to 25 in the form of the cured coating
film were obtained.
<Weather Resistance Test of Cured Coating Film>
[0154] The method of the weather resistance test of the cured
coating film was as described below. Using a Sunshine Carbon
Weather Meter (WEL-SUN-HC-B type weather resistance tester
manufactured by Suga Test Instruments Co., Ltd.), the cured coating
film on the test pieces was tested. The black panel temperature of
the weather resistance tester is 63.+-.3.degree. C. Changes of the
cured coating film after exposed to cycles of rainfall of 12
minutes and irradiation of 48 minutes for 3500 hours were observed
in the following manner.
<Evaluation Method of Samples Before and after Weather
Resistance Test>
(1) Outer Appearance
[0155] The outer appearance of the test pieces after the weather
test was visually evaluated. The test samples whose surfaces were
free from cracks and natural separation were rated as "G" The test
samples whose surfaces had cracks or natural separation were rated
as "NG"
(2) Measurement of Transparency of Test Sample
[0156] The total light transmittance and haze value of the test
pieces were measured using a Haze Meter HM-65W Type (manufactured
by Murakami Color Research Laboratory Co., Ltd.) according to the
method described in JIS-K7105. When the measured haze value after
the weather resistance test was 0% or more and less than 5%, such
test pieces were rated as good (1). When the haze value was 5% or
more and less than 10%, such test pieces were rated as medium (2).
When the haze value was 10% or more, such test pieces were rated as
bad (3).
(3) Measurement of Yellowness (Yellow Index) of Test Sample
[0157] Yellowness (yellow index) of the test pieces were measured
using a Multi Channel Photo Detector MCPD-3000 (manufactured by
Otsuka Electronics Co., Ltd.) according to the method described in
JIS-K7105. When the measured yellow index value after the weather
resistance test was 0 or more and less than 5, such test pieces
were rated as good (1). When the yellow index value was 5 or more
and less than 10, such test pieces were rated as medium (2). When
the yellow index was 10 or more, such test pieces were rated as bad
(3).
[0158] Table 3 shows the compositions of the active energy
ray-curable compositions according to Examples 6 to 15 Table 4
shows the compositions of the active energy ray-curable
compositions according to Comparative Examples 6 to 10. The results
of the weather resistance test conducted on the prepared
compositions are also shown. The numeric values in Tables 3 and 4
are represented in parts by mass.
TABLE-US-00003 TABLE 3 Monomer DPHA TAIC CA1 BNP MPG MAPO HBPB
Product (A) [parts] [parts] [parts] [parts] [parts] [parts] [parts]
[parts] Example 6 11 A-1 1 33 40 27 1 1 1 10 Example 7 12 A-2 1 33
40 27 1 1 1 10 Example 8 13 A-3 1 33 40 27 1 1 1 10 Example 9 14
A-4 1 33 40 27 1 1 1 10 Example 10 15 A-5 1 33 40 27 1 1 1 10
Example 11 16 A-1 2 33 40 27 1 1 1 10 Example 12 17 A-2 2 33 40 27
1 1 1 10 Example 13 18 A-3 2 33 40 27 1 1 1 10 Example 14 19 A-4 2
33 40 27 1 1 1 10 Example 15 20 A-5 2 33 40 27 1 1 1 10 Results of
Weather Resistance Test Total Light Solvent Transmittance n-butyl
Outer (%) Haze (%) Yellowness acetate ECA Appear- before after
before after before after [parts] [parts] ance test test test test
Rating test test Rating Example 6 15 13 G 89.1 87.2 1.3 1.4 1 1.2
1.5 1 Example 7 15 13 G 88.9 86.9 1.1 1.5 1 1.2 1.8 1 Example 8 15
13 G 89.6 87.9 0.9 1.3 1 1.1 1.3 1 Example 9 15 13 G 88.9 87.1 1.1
1.3 1 1.2 1.3 1 Example 10 15 13 G 90.0 86.9 1.0 1.2 1 1.3 1.6 1
Example 11 15 13 G 89.2 88.3 1.0 1.3 1 1.4 1.8 1 Example 12 15 13 G
90.1 88.6 0.9 1.6 1 1.3 1.4 1 Example 13 15 13 G 88.9 88.1 0.8 1.9
1 1.5 1.8 1 Example 14 15 13 G 89.8 88.8 0.8 1.8 1 1.8 2.0 1
Example 15 15 13 G 90.2 87.9 1.3 2.0 1 1.7 2.1 1
TABLE-US-00004 TABLE 4 Monomer DPHA TAIC CA1 BNP MPG MAPO HBPB
Product (A) [parts] [parts] [parts] [parts] [parts] [parts] [parts]
[parts] Comparative 21 LS- 1 33 40 27 1 1 1 10 Example 6 292
Comparative 22 T-152 1 33 40 27 1 1 1 10 Example 7 Comparative 23
LS- 1 33 40 27 1 1 1 10 Example 8 3410 Comparative 24 PR-31 1 33 40
27 1 1 1 10 Example 9 Comparative 25 -- -- 33 40 27 1 1 1 10
Example 10 Results of Weather Resistance Test Total Light Solvent
Transmittance n-butyl Outer (%) Haze (%) Yellowness acetate ECA
Appear- before after before after before after [parts] [parts] ance
test test test test Rating test test Rating Comparative 15 13 G
89.2 87.2 3.2 12.3 3 1.8 6.9 2 Example 6 Comparative 15 13 G 90.2
86.9 1.0 8.6 2 1.5 3.5 1 Example 7 Comparative 15 13 G 88.6 86.5
1.9 12.1 3 1.6 3.8 1 Example 8 Comparative 15 13 G 89.5 85.9 2.1
6.9 2 1.6 2.9 1 Example 9 Comparative 15 13 G 88.9 86.9 2.3 10.8 3
1.8 2.8 1 Example 10
[0159] In Tables 3 and 4, the following signs represent the
following compounds.
[0160] DPHA: di-pentaerythritol hexaacrylate
[0161] UA1: urethane acrylate having a molecular weight of 2500 and
synthesized from 2 mol of dicyclohexyl methanediol, 1 mol of
nonabutylene glycol and 2 mol of 2-hydroxyethyl acrylate
[0162] TAIC: tris (2-acryloyloxyethyl)isocyanurate
[0163] HBPB: 2-(2-hydroxy-5-tert-butylphenyl) benzotriazole
[0164] BNP: benzophenone
[0165] MPG: methyl phenylglyoxylate
[0166] MAPO: 2,4,6-trimethylbenzoyl diphenyl phosphine oxide
[0167] ECA: ethyl diglycol acetate
[0168] LS-292: Product name "Sanol LS-292" manufactured by Sankyo
Kasei Co., Ltd. (a mixture of bis
(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate and methyl
(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate)
[0169] T-152: Product name "TINUVIN 152" manufactured by Ciba
Specialty Chemicals Inc.
(2,4-bis[N-butyl-N-(1-cyclohexyloxy-2,2,6,6-tetramethyl
piperidine-4-yl)amino]-6-(2-hydroxyethylamine)-1,3,5-triazin)
[0170] LS-3410: Product name "Sanol LS-3410" manufactured by Sankyo
Kasei Co., Ltd. (N-methyl-2,2,6,6-tetramethyl piperidyl
methacrylate) PR-31: Product name "SANDUVOR PR-31" manufactured by
Clariant (Japan) K.K. (propanedioic acid
[{4-methoxyphenyl}methylene]-bis(1,2,2,6,6-pentamethyl-4-piperidyl)
ester)
[0171] In the cured coating film according to Examples 6 to 15, the
monomer (A) was used. Accordingly, the cured coating film according
to Examples 6 to 15 had good outer experience, good transparency,
and yellowness after the weather resistance test.
[0172] In the cured coating film according to Comparative Examples
6 to 10, only a known light stabilizer (i.e., other than the
monomer (A)) was used, or no HALS portion was included. Therefore,
in the cured coating film according to Comparative Examples 6 to
10, either haze value after the weather resistance test after the
weather resistance test or the yellowness was not good.
REFERENCE SIGNS LIST
[0173] 1 Feeding die [0174] 2 Curable composition [0175] 2'
Transparent resin sheet [0176] 3 Endless belt [0177] 4 Active
energy ray irradiator [0178] 5 Active energy ray-transmissive film
[0179] 6 Active energy ray-transmissive film feeding device [0180]
7 Active energy ray-transmissive film winding device [0181] 8
Upper-side pressing roll [0182] 8' Lower-side pressing roll [0183]
9 Pre-heating mechanism [0184] 10 Post-heating mechanism [0185] 11
Main pulley [0186] 12 Main pulley
* * * * *