U.S. patent application number 10/515420 was filed with the patent office on 2005-10-27 for dispersion and process for production of moldings by using the same.
This patent application is currently assigned to Daicel Chemical Industries, Ltd.. Invention is credited to Ito, Hisayoshi.
Application Number | 20050239925 10/515420 |
Document ID | / |
Family ID | 29586011 |
Filed Date | 2005-10-27 |
United States Patent
Application |
20050239925 |
Kind Code |
A1 |
Ito, Hisayoshi |
October 27, 2005 |
Dispersion and process for production of moldings by using the
same
Abstract
A shaped article (e.g., a porous material, and a spherical
particle) comprising (A) a resin component is produced by kneading
the resin component (A) (e.g., a thermoplastic resin) and a
water-soluble auxiliary component (B) to prepare a dispersed
composition, and eluting the auxiliary component (B) from the
dispersed composition. The auxiliary component (B) may comprise 100
parts by weight of an oligosaccharide (B.sub.1) and 0.5 to 100
parts by weight of a water-soluble plasticizing component (B.sub.2)
for plasticizing the oligosaccharide. The oligosaccharide (B.sub.1)
may comprise a tetrasaccharide. The plasticizing component
(B.sub.2) may comprise a saccharide or a sugar alcohol. Use of the
dispersed composition ensures to form a shaped article having a
given shape industrially with advantage even in the case of using a
wide variety of resin components.
Inventors: |
Ito, Hisayoshi; (Himeji-shi,
JP) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Assignee: |
Daicel Chemical Industries,
Ltd.
Sakai-shi
JP
|
Family ID: |
29586011 |
Appl. No.: |
10/515420 |
Filed: |
November 23, 2004 |
PCT Filed: |
May 16, 2003 |
PCT NO: |
PCT/JP03/06171 |
Current U.S.
Class: |
524/27 ;
264/333 |
Current CPC
Class: |
C08K 5/0016 20130101;
C08J 2201/0422 20130101; C08J 9/26 20130101 |
Class at
Publication: |
524/027 ;
264/333 |
International
Class: |
C08J 003/00; C08L
005/00; B28B 003/00 |
Foreign Application Data
Date |
Code |
Application Number |
May 29, 2002 |
JP |
2002-156112 |
Jan 31, 2003 |
JP |
2003-023536 |
Claims
1. A dispersed composition comprising (A) a resin component and (B)
a water-soluble auxiliary component, wherein the auxiliary
component (B) comprises at least (B.sub.1) an oligosaccharide.
2. A dispersed composition according to claim 1, wherein the
auxiliary component (B) forms a continuous phase in an
islands-in-the-sea structure or in a bicontinuous phase.
3. A dispersed composition according to claim 1, wherein the resin
component (A) comprises a thermoplastic resin.
4. A dispersed composition according to claim 1, wherein the resin
component (A) comprises at least one member selected from the group
consisting of a polyester-series resin, a polyamide-series resin, a
polyurethane-series resin, a poly(thio)ether-series resin, a
polycarbonate-series resin, a polysulfone-series resin, a
polyolefinic resin, a (meth)acrylic resin, a styrenic resin, a
vinyl-series resin, a cellulose derivative, and a thermoplastic
elastomer.
5. A dispersed composition according to claim 1, wherein the
oligosaccharide (B.sub.1) has a melting point or a softening point
at a temperature higher than a heat distortion temperature of the
resin component (A), or is decomposed at a temperature higher than
the heat distortion temperature of the resin component (A).
6. A dispersed composition according to claim 1, wherein the
oligosaccharide (B.sub.1) comprises at least one member selected
from the group consisting of a disaccharide, a trisaccharide, a
tetrasaccharide, a pentasaccharide, a hexasaccharide, a
heptasaccharide, an octasaccharide, a nonasaccharide, and a
decasaccharide.
7. A dispersed composition according to claim 1, wherein the
oligosaccharide (B.sub.1) comprises at least a tetrasaccharide.
8. A dispersed composition according to claim 1, wherein the
oligosaccharide (B.sub.1) comprises at least one tetrasaccharide
selected from the group consisting of (1) maltotetraose, (2)
isomaltotetraose, (3) stachyose, (4) cellotetraose, (5) scorodose,
(6) lychnose, and (7) a tetraose having a sugar or sugar alcohol
attached to a reducing end of panose.
9. A dispersed composition according to claim 1, wherein the
oligosaccharide (B.sub.1) comprises at least one member selected
from the group consisting of a starch sugar, a
galactooligosaccharide, a coupling sugar, a fructooligosaccharide,
a xylooligosaccharide, a soybean oligosaccharide, a chitin
oligosaccharide and a chitosan oligosaccharide.
10. A dispersed composition according to claim 9, wherein the
oligosaccharide (B.sub.1) contains a tetrasaccharide in a
proportion of not less than 60% by weight.
11. A dispersed composition according to claim 1, wherein the
viscosity of the 50% by weight aqueous solution of the
oligosaccharide (B.sub.1) is not less than 1 Pa.multidot.s as
measured at a temperature of 25.degree. C. by a B-type
viscometer.
12. A dispersed composition according to claim 1, wherein the
auxiliary component (B) further comprises a water-soluble
plasticizing component (B.sub.2) for plasticizing the
oligosaccharide (B.sub.1).
13. A dispersed composition according to claim 12, wherein the
melting point or softening point of the plasticizing component
(B.sub.2) is not higher than the heat distortion temperature of the
resin component (A).
14. A dispersed composition according to claim 12, wherein the
plasticizing component (B.sub.2) comprises at least one member
selected from the group consisting of a saccharide and a sugar
alcohol.
15. A dispersed composition according to claim 14, wherein the
saccharide comprises at least one member selected from the group
consisting of a monosaccharide and a disaccharide.
16. A dispersed composition according to claim 14, wherein the
saccharide comprises a reducing sugar.
17. A dispersed composition according to claim 15, wherein the
monosaccharide comprises at least one member selected from the
group consisting of a triose, a tetrose, apentose, a hexose, a
heptose, a octose, a nonose, a decose and a dodecose, and the
disaccharide comprises at least one member selected from the group
consisting of a homodisaccharide of one of said monosaccharides and
a heterodisaccharide of two of said monosaccharides.
18. A dispersed composition according to claim 14, wherein the
sugar alcohol comprises at least one member selected from the group
consisting of a tetrytol, a pentitol, a hexitol, a heptitol, an
octitol, a nonitol, a decitol and a dodecitol.
19. A dispersed composition according to claim 14, wherein the
sugar alcohol comprises at least one member selected from the group
consisting of erythritol, pentaerythritol, arabitol, ribitol,
xylitol, sorbitol, dulcitol and mannitol.
20. A dispersed composition according to claim 12, wherein the
resin component (A) has a Vicat softening point defined by JIS K
7206 of 60 to 300.degree. C.; the viscosity of the 50% by weight
aqueous solution of the oligosaccharide (B.sub.1) is 3 to 100
Pa.multidot.s as measured at a temperature of 25.degree. C. by a
B-type viscometer; a melt flow rate defined by JIS K 7210 of the
auxiliary component (B) comprising the oligosaccharide (B.sub.1)
and the plasticizing component (B.sub.2) is not less than 1 as
measured at a temperature 30.degree. C. higher than said Vicat
softening point.
21. A dispersed composition according to claim 1, wherein the ratio
(weight ratio) of the resin component (A) relative to the auxiliary
component (B) [the resin component (A)/the auxiliary component (B)]
is 99/1 to 1/99.
22. A dispersed composition according to claim 12, wherein the
ratio (weight ratio) of the oligosaccharide (B.sub.1) relative to
the plasticizing component (B.sub.2) [the oligosaccharide
(B.sub.1)/the plasticizing component (B.sub.2)] is 99/1 to
50/50.
23. A dispersed composition according to claim 12, wherein the
resin component (A) comprises at least one member selected from the
group consisting of a polyamide-series resin, a styrenic resin, a
polyolefinic resin, a vinyl alcohol-series resin, a cellulose
derivative, a halogen-containing resin, an aliphatic
polyester-series resin and a thermoplastic elastomer; the
oligosaccharide (B.sub.1) constituting the auxiliary component (B)
comprises at least one member selected from the group consisting of
a starch sugar, a galactooligosaccharide, a coupling sugar, a
fructooligosaccharide, a xylooligosaccharide, a soybean
oligosaccharide, a chitin oligosaccharide and a chitosan
oligosaccharide; the plasticizing component (B.sub.2) comprises at
least one member selected from the group consisting of erythritol,
pentaerythritol, xylitol and sorbitol; the ratio (weight ratio) of
the resin component (A) relative to the auxiliary component (B)
[the resin component (A)/the auxiliary component (B)] is 90/10 to
5/95; and the ratio (weight ratio) of the oligosaccharide (B.sub.1)
relative to the plasticizing component (B.sub.2) [the
oligosaccharide (B.sub.1)/the plasticizing component (B.sub.2)] is
95/5 to 60/40.
24. A water-soluble auxiliary agent used in combination with a
resin to form a dispersed composition, wherein the water-soluble
auxiliary agent comprises at least an oligosaccharide
(B.sub.1).
25. A process for producing a shaped article comprising a resin
component (A) comprising: eluting an auxiliary component (B) from a
dispersed composition recited in claim 1.
26. A process according to claim 25, wherein the shaped article is
a porous material or particles.
27. A process according to claim 26, wherein the average pore size
of the porous material is 0.1 to 100 .mu.m, and the coefficient of
variation of the pore size is not greater than 60.
28. A process according to claim 26, wherein the average particle
size of the particle is 0.1 to 100 .mu.m, and the coefficient of
variation of the particle size is not greater than 60.
Description
TECHNICAL FIELD
[0001] The present invention relates to a dispersed composition (or
a resin composition forming a disperse system) which comprises a
resin component and a water-soluble auxiliary component and is
useful for shaping the resin component into a figure such as a
porous material or a particulate, a process for producing a shaped
article by using the dispersed composition, and a water-soluble
auxiliary agent to be used in combination with a resin to form a
dispersed composition.
BACKGROUND ART
[0002] For producing a resinous shaped article having a desired
shape such as a porous material or a particle, various processes
have been utilized. For example, Japanese Patent Application
Laid-Open No. 2825/2001 (JP-2001-2825A) discloses a process for
producing a porous material, comprising melt-kneading a
pore-forming agent fusible at a molding temperature and a high
molecular substance such as a resin, molding the kneaded matter to
make a full (non-porous) shaped article containing the pore-forming
agent, and then washing out the pore-forming agent from the full
shaped article with a solvent. This document mentions
pentaerythritol, L-erythritol and others as a pore-forming agent,
and water or an organic solvent such as an alcohol compound as a
solvent for eluting the pore-forming agent (auxiliary component).
According to this process, a porous material having uniform fine
pores can be produced.
[0003] However, in the case where a proportion of a pore-forming
agent (erythritol having a low melting point or pentaerythritol
having a high melting point) in a resin composition is increased,
the resin composition is deteriorated in melt-kneading property and
the size uniformity of the generated pores is decreased. More
specifically, in kneading of the resin and erythritol, melting of
erythritol having a low melting point induces decrease in viscosity
of the resin composition and remarkable deterioration in
melt-kneading property of the resin composition. Moreover, a resin
composition containing pentaerythritol at a high proportion can be
melt-kneaded, however, part of pentaerythritol remains as an
unmelted matter and it is impossible to obtain a porous material
having a uniform pore size.
[0004] Japanese Patent Application Laid-Open No. 176065/1998
(JP-10-176065A) discloses a process for obtaining a spherical fine
particle of a thermoplastic resin (a), which comprises
melt-kneading the thermoplastic resin (a) to be powdered with other
one or more of thermoplastic resins (b) to give a resin composition
comprising the resin (a) constituting the dispersed phase and the
resin (b) constituting the continuous phase, and washing the resin
composition with a solvent capable of dissolving the resin (a) and
incapable of dissolving the resin (b).
[0005] In this process, however, it is necessary not only that the
dispersed phase and the continuous phase are incompatible with each
other, but also that an applicable combination of the resin
constituting the continuous phase with the solvent is selected
depending on the kind of the resin of the dispersed phase.
Therefore, the combination of the resins should be limited to a
specific one, and in addition, the combination of the resin with
the solvent should be limited to a specific one. Further, in a step
of cooling the dispersed composition, the resins incompatible with
each other tend to form a large phase in the separation. Therefore,
if the dispersed composition is not carefully solidified, the once
produced dispersed phases will be gathered or aggregated again, and
as a result, it is impossible to obtain a spherical fine particle
having a given shape.
[0006] Furthermore, the resin constituting the continuous phase is
finally recovered, or discarded in a dissolved state, because of
being uninvolved in the resin fine particle as a product. However,
recovery of the resin in the solution not only is very difficult
but also is a caused factor of increase in the production cost of
the resin particle. Moreover, in the case of discarding the resin
solution directly as a waste fluid, there is concern about adverse
effects on the environment.
[0007] Japanese Patent Application Laid-Open No. 13816/1985
(JP-60-13816A) proposes a process for producing a thermoplastic
resin particle, which comprises melting a polyethylene glycol and a
thermoplastic resin with stirring, then putting the molten mixture
in water to solidify the both polymers, and then removing the
polyethylene glycol from the resulting matter with water. Japanese
Patent Application Laid-Open No. 9433/1986 (JP-61-9433A) discloses
a process for producing a thermoplastic resin particle, which
comprises melting a thermoplastic resin and a polyethylene oxide
with stirring, then cooling the molten mixture, and removing the
polyethylene oxide from the mixture with water. Japanese Patent
Application Laid-Open No. 165457/1997 (JP-9-165457A) discloses a
process for producing a resin fine particle, which comprises mixing
a melt-formable and water-soluble polymer (such as a polyvinyl
alcohol-series resin, a denatured starch, or a polyethylene oxide)
and a thermoplastic resin to give a melt-shaped product, and then
removing the water-soluble polymer from the shaped product with
water.
[0008] Even in these processes, however, since it is necessary that
a resin and a water-soluble polymer are incompatible with each
other, a selectable combination of the resin is limited, and in
addition, the particle size distribution of thus resulting resin
particle is insufficient in uniformity. Further, these
water-soluble polymers having small solubilities to water need a
large amount of water for dissolution, and in addition,
significantly deteriorate productivity of resin particles due to
the slow velocity of dissolution. Furthermore, since such
water-soluble polymers are often derived from unnatural products, a
waste fluid containing such a water-soluble polymer dissolved
therein adversely affects on the environment.
[0009] It is therefore an object of the present invention to
provide a water-soluble auxiliary component (or a water-soluble
auxiliary agent) being a saccharide yet kneadable with a resin
component uniformly, and a dispersed composition (or a resin
composition forming a disperse system) obtained by using the
water-soluble auxiliary component.
[0010] It is another object of the present invention to provide a
water-soluble auxiliary component (or a water-soluble auxiliary
agent) capable of forming a given shaped article industrially with
advantage even in the case of using a wide range of a resin
component, and a dispersed composition (or a resin composition
forming a disperse system) obtained by using the water-soluble
auxiliary component.
[0011] It is still another object of the present invention to
provide a water-soluble auxiliary component (or a water-soluble
auxiliary agent) capable of being kneaded even if contained in a
high proportion relative to a resin component and capable of
forming a uniform phase-separation structure with the resin
component, and a dispersed composition (or a resin composition for
forming a disperse system) obtained by using the water-soluble
auxiliary component.
[0012] It is a further object of the present invention to provide a
process for producing a shaped article by using a dispersed
composition (or a resin composition forming a disperse system)
comprising a water-soluble auxiliary component (or a water-soluble
auxiliary agent) and a resin component, wherein the water-soluble
auxiliary component can not only be easily eluted with water but
also reduce the burden on the environment.
[0013] It is a still further object of the present invention to
provide a process for producing a shaped article having a uniform
pore size or a uniform particle size.
DISCLOSURE OF THE INVENTION
[0014] The inventor of the present invention made intensive studies
to achieve the above objects and finally found that a dispersed
composition formed by using an auxiliary component comprising at
least an oligosaccharide, which is a saccharide and yet kneadable
with a resin uniformly in combination with a resin component can
provide a shaped article having a uniform pore size or a uniform
particle size by using a wide range of a resin component. The
present invention was accomplished based on the above finding.
[0015] That is, the dispersed composition (or dispersion) of the
present invention comprises (A) a resin component and (B) a
water-soluble auxiliary component, and the auxiliary component (B)
comprises at least (B.sub.1) an oligosaccharide. The auxiliary
component (B) may form a continuous phase in an islands-in-the-sea
structure or in a bicontinuous phase. The resin component (A) may
comprise a thermoplastic resin [for example, a polyester-series
resin (e.g., an aliphatic polyester-series resin), a
polyamide-series resin, a polyurethane-series resin, a
poly(thio)ether-series resin, a polycarbonate-series resin, a
polysulfone-series resin, a polyolefinic resin, a (meth)acrylic
resin, a styrenic resin, a vinyl-series resin, a cellulose
derivative, and a thermoplastic elastomer]. The oligosaccharide
(B.sub.1) may have a melting point or a softening point at a
temperature higher than a heat distortion temperature of the resin
component (A), or may be decomposed at a temperature higher than
the heat distortion temperature of the resin component (A). For
example, the melting point or softening point of the
oligosaccharide (B.sub.1) may be higher than the heat distortion
temperature of the resin component (A), and may for example be
about 90 to 290.degree. C. Moreover, the oligosaccharide (B.sub.1)
may be thermally decomposed without having an obvious melting point
or softening point at a temperature higher than the heat distortion
temperature of the resin component (A). The heat distortion
temperature of the resin may be, for example, determined as a Vicat
softening point defined by Japanese Industrial Standards (JIS) K
7206. The heat distortion temperature (Vicat softening point) of
the resin may be, for example, about 60 to 300.degree. C., and
preferably about 80 to 260.degree. C. The oligosaccharide (B.sub.1)
may comprise a disaccharide, a trisaccharide, a tetrasaccharide, a
pentasaccharide, a hexasaccharide, a heptasaccharide, an
octasaccharide, a nonasaccharide, a decasaccharide, and others, or
may comprise at least a tetrasaccharide. The oligosaccharide
(B.sub.1) may comprise maltotetraose, isomaltotetraose, stachyose,
cellotetraose, scorodose, lychnose, and a tetraose having a sugar
or sugar alcohol attached to a reducing end of panose. Moreover,
the oligosaccharide (B.sub.1) may comprise an oligosaccharide
composition such as a starch sugar, a galactooligosaccharide, a
coupling sugar, a fructooligosaccharide, a xylooligosaccharide, a
soybean oligosaccharide, a chitin oligosaccharide or a chitosan
oligosaccharide. The content of the tetrasaccharide in such an
oligosaccharide (B.sub.1) may be not less than 60% by weight. The
viscosity of the 50% by weight aqueous solution of the
oligosaccharide (B.sub.1) may be not less than 1 Pa.multidot.s
(e.g., about 3 to 100 Pa.multidot.s) as measured at a temperature
of 25.degree. C. by a B-type viscometer.
[0016] Further, the auxiliary component (B) may contain a
water-soluble plasticizing component (or plasticizer) (B.sub.2) for
plasticizing the oligosaccharide (B.sub.1). The combination use of
the oligosaccharide (B.sub.1) and the plasticizing component
(B.sub.2) ensures to plasticize or soften the oligosaccharide
(B.sub.1) effectively even when the oligosaccharide (B.sub.1) is of
thermally decomposable. The melting point or softening point of the
plasticizing component (B.sub.2) may be not higher than the heat
distortion temperature (the above Vicat softening point) of the
resin component (A). Moreover, the melt flow rate defined by JIS K
7210 of the auxiliary component (B) comprising the oligosaccharide
(B.sub.1) and the plasticizing component (B.sub.2) may be not less
than 1 (e.g., about 1 to 40) as measured at a temperature
30.degree. C. higher than the heat distortion temperature of the
resin component (A). The plasticizing component (B.sub.2) may
comprise a saccharide (e.g., a monosaccharide and a disaccharide)
and a sugar alcohol, and others. Such a saccharide may comprise a
reducing sugar. The monosaccharide may comprise a triose, a
tetrose, apentose, ahexose, aheptose, anoctose, anonose, adecose
and a dodecose, and the disaccharide may comprise a
homodisaccharide of the above monosaccharide and a
heterodisaccharide of the above monosaccharides. The sugar alcohol
may comprise a tetrytol (e.g., erythritol), a pentitol (e.g.,
pentaerythritol, arabitol, ribitol, and xylitol), a hexitol (e.g.,
sorbitol, dulcitol and mannitol), a heptitol, an octitol, a
nonitol, a decitol and a dodecitol. Moreover, the ratio (weight
ratio) of the resin component (A) relative to the auxiliary
component (B) [the resin component (A)/the auxiliary component (B)]
may be about 99/1 to 1/99. In the auxiliary component (B), the
ratio (weight ratio) of the oligosaccharide (B.sub.1) relative to
the plasticizing component (B.sub.2) [the oligosaccharide
(B.sub.1)/the plasticizing component (B.sub.2)] may be about 99/1
to 50/50.
[0017] The present invention also includes a water-soluble
auxiliary agent used in combination with a resin to form a
dispersed composition, wherein the water-soluble auxiliary agent
comprises at least an oligosaccharide (B.sub.1). Further, the
present invention also includes a process for producing a shaped
article comprising a resin component (A), comprising eluting an
auxiliary component (B) from the dispersed composition, and the
shaped article may include a porous material having an average pore
size of 0.1 to 100 .mu.m and a coefficient of variation of the pore
size of not greater than 60, and a particle having an average
particle size of 0.1 to 100 m and a coefficient of variation of the
particle size of not greater than 60.
[0018] Incidentally, in the present invention, the dispersed
composition may be a resin composition forming a disperse system
containing a resin component and an auxiliary component, and may be
used synonymously with the term "resin composition" accordingly.
Moreover, the water-soluble auxiliary component may be referred to
as a pore-forming agent.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a scanning electron micrograph of a cross section
of a porous material obtained in Example 2.
[0020] FIG. 2 is a scanning electron micrograph of particles
obtained in Example 13.
DETAILED DESCRIPTION OF THE INVENTION
[0021] [Resin Component (A)]
[0022] Examples of a resin constituting the resin component include
a thermoplastic resin [for example, a condensation-series
thermoplastic resin such as a polyester-series resin (e.g., an
aromatic polyester-series resin, and an aliphatic polyester-series
resin), a polyamide-series resin, a polyurethane-series resin, a
poly(thio)ether-series resin (e.g., a polyacetal-series resin, a
polyphenylene ether-series resin, a polysulfide-series resin, and a
polyether ketone-series resin), a polycarbonate-series resin, a
polysulfone-series resin, or a polyimide-series resin; a vinyl
polymerization-series thermoplastic resin such as a polyolefinic
resin, a (meth)acrylic resin, a styrenic resin, or a vinyl-series
resin (e.g., a halogen-containing resin, a vinyl ester-series
resin, and a vinyl alcohol-series resin); and a resin derived from
a natural product, such as a cellulose derivative], and a
thermosetting resin (e.g., an epoxy resin, an unsaturated polyester
resin, a diallyl phthalate resin, and a silicone resin). These
resins may be used singly or in combination. As the resin
component, a thermoplastic resin, or a water-insoluble resin (e.g.,
a water-insoluble thermoplastic resin) is usually employed.
[0023] (Thermoplastic Resin)
[0024] (1) Polyester-Series Resin
[0025] The polyester-series resin includes, for example, a
homopolyester or copolyester obtained by a polycondensation of a
dicarboxylic acid component and a diol component; a homopolyester
or copolyester obtained by a polycondensation of a
hydroxycarboxylic acid; and a homopolyester or copolyester obtained
by a ring opening polymerization of a lactone. These
polyester-series resins may be used singly or in combination.
[0026] The dicarboxylic acid component includes, for example, an
aromatic dicarboxylic acid [e.g., an aromatic dicarboxylic acid
having about 8 to 20 carbon atoms, such as terephthalic acid,
isophthalic acid, phthalic acid; an alkyl-substituted phthalic acid
such as methylterephthalic acid or methylisophthalic acid; a
naphthalenedicarboxylic acid (e.g., 2,6 -naphthalenedicarboxylic
acid, 2,7-naphthalenedicarboxylic acid, and
1,5-naphthalenedicarboxylic acid); a diphenyldicarboxylic acid such
as 4,4'-diphenyldicarboxylic acid or 3,4'-diphenyldicarboxylic
acid; a diphenoxyethanedicarboxylic acid such as
4,4'-diphenoxyethanedicarboxylic acid; a diphenyl
ether-dicarboxylic acid such as diphenyl ether-4,4'-dicarboxylic
acid; a diphenylalkanedicarboxylic acid such as
diphenylmethanedicarboxylic acid or diphenylethanedicarboxylic
acid; or a diphenylketonedicarboxylic acid], an aliphatic
dicarboxylic acid (e.g., an aliphatic dicarboxylic acid having
about 2 to 40 carbon atoms, such as oxalic acid, succinic acid,
adipic acid, azelaic acid, sebacic acid, dodecanoic diacid,
hexadecanedicarboxylic acid, or dimeric acid), and an alicyclic
dicarboxylic acid (e.g., an alicyclic dicarboxylic acid having
about 8 to 12 carbon atoms, such as cyclohexanedicarboxylic acid,
hexahydrophthalic acid, hexahydroisophthalic acid,
hexahydroterephthalic acid, or himic acid). These dicarboxylic acid
components may be used singly or in combination.
[0027] Incidentally, the dicarboxylic acid component also includes
an ester-formable derivative, e.g., a lower alkyl ester such as a
dimethyl ester, an acid anhydride, and an acid halide such as an
acid chloride.
[0028] Examples of the diol component include an aliphatic
C.sub.2-12diol (e.g., a C.sub.2-12alkanediol such as ethylene
glycol, propylene glycol, trimethylene glycol, 1,4-butanediol,
1,3-butanediol, neopentyl glycol, or hexanediol; and a
(poly)oxyC.sub.2-4alkylene glycol such as diethylene glycol,
triethylene glycol, or dipropylene glycol); and an alicyclic
C.sub.6-12diol (e.g., cyclohexanediol, and cyclohexanedimethanol);
an aromatic C.sub.6-20diol (e.g., a benzenediol compound such as
resorcinol or hydroquinone; a naphthalenediol compound; a bisphenol
compound such as bisphenol A, F, or AD; and an adduct of a
bisphenol compound with an alkylene oxide). These diol components
may be used singly or in combination.
[0029] The hydroxycarboxylic acid includes, for example, an
aliphatic C.sub.2-6hydroxycarboxylic acid such as glycolic acid,
lactic acid, hydroxypropionic acid, hydroxybutyric acid, glyceric
acid, or tartronic acid; and an aromatic hydroxycarboxylic acid
such as hydroxybenzoic acid, or hydroxynaphthoic acid. These
hydroxycarboxylic acids may be used singly or in combination.
[0030] Examples of the lactone include a C.sub.3-12lactone such as
propiolactone, butyrolactone, valerolactone, or caprolactone. These
lactones may be used singly or in combination. Among these
lactones, a C.sub.4-10lactone, in particular caprolactone (e.g.,
.epsilon.-caprolactone), is preferred.
[0031] The polyester-series resin includes an aromatic
polyester-series resin, an aliphatic polyester-series resin, and
others.
[0032] Examples of the aromatic polyester-series resin include a
homopolyester or copolyester obtained by polycondensation of the
aromatic dicarboxylic acid (preferably, e.g., an aromatic
dicarboxylic acid having about 8 to 20 carbon atoms, such as
terephthalic acid, isophthalic acid, phthalic acid or
naphthalenedicarboxylic acid) and the aliphatic diol (preferably,
e.g., an aliphatic C.sub.2-12diol such as ethylene glycol,
propylene glycol, 1,4-butanediol or 1,3-butanediol) or the
alicyclic diol (preferably, e.g., an alicyclic C.sub.6-20diol such
as cyclohexanedimethanol), and preferably include a homopolyester
or copolyester having an alkylene arylate unit such as an alkylene
terephthalate or an alkylene naphthalate as a main unit (e.g., not
less than 50% by weight). The copolymerizable component may include
a polyoxyC.sub.2-4alkylene glycol having a repeating oxyalkylene
unit of about 2 to 4 [e.g., a glycol compound containing a
poly(oxyC.sub.2-4alkylene) unit such as diethylene glycol], or an
aliphatic dicarboxylic acid having about 6 to 12 carbon atoms
(e.g., adipic acid, pimelic acid, suberic acid, azelaic acid, and
sebacic acid).
[0033] More specifically, as the aromatic polyester-series resin,
there may be exemplified a polyalkylene terephthalate [e.g., a
polycycloalkanediC.sub.1-4alkylene terephthalate such as a
poly(1,4-cyclohexyldimethylene terephthalate) (PCT); and a
polyC.sub.2-4alkylene terephthalate such as a polyethylene
terephthalate (PET) or a polybutylene terephthalate (PBT)], a
polyC.sub.2-4alkylene naphthalate corresponding to the polyalkylene
terephthalate (e.g., polyethylene naphthalate), a polyethylene
terephthalate copolyester containing an ethylene terephthalate unit
as a main unit, and a polybutylene terephthalate copolyester
containing a butylene terephthalate unit as a main unit. The
aromatic polyester-series resin may be a liquid crystalline
polyester.
[0034] Examples of the aliphatic polyester-series resin include a
homopolyester or copolyester obtained by a polycondensation of the
aliphatic dicarboxylic acid component (e.g., an aliphatic
dicarboxylic acid having about 2 to 6 carbon atoms, such as oxalic
acid, succinic acid or adipic acid, and preferably oxalic acid or
succinic acid) and the aliphatic diol component (e.g., an aliphatic
C.sub.2-6diol such as ethylene glycol, propylene glycol,
1,4-butanediol, 1,3-butanediol, neopentyl glycol or hexanediol, and
preferably an aliphatic C.sub.2-4diol such as ethylene glycol,
1,4-butanediol or neopentyl glycol), a homopolyester or copolyester
of the aliphatic hydroxycarboxylic acid (e.g., an aliphatic
C.sub.2-6hydroxycarboxylic acid such as glycolic acid, lactic acid,
hydroxypropionic acid or hydroxybutyric acid, and preferably an
aliphatic C.sub.2-4hydroxycarboxylic acid such as glycolic acid or
lactic acid), and a homopolylactone or copolylactone obtained by a
ring opening polymerization of the lactone (preferably, a
C.sub.4-10lactone such as caprolactone) with an initiator (a
bifunctional or trifunctional initiator, e.g., an active
hydrogen-containing compound such as an alcohol compound). The
copolymerizable component may include a polyoxyC.sub.2-4alkylene
glycol having a repeating oxyalkylene unit number of about 2 to 4
[e.g., a glycol compound containing a poly(oxyC.sub.2-4alkylene)
unit such as diethylene glycol], or an aliphatic dicarboxylic acid
having about 6 to 12 carbon atoms (e.g., adipic acid, pimelic acid,
suberic acid, azelaic acid, and sebacic acid).
[0035] More specifically, the aliphatic polyester-series resin
includes, for example, a polyester-series resin obtained by a
polycondensation of a dicarboxylic acid component and a diol
component (for example, a polyC.sub.2-6alkylene oxalate such as a
polyethylene oxalate, a polybutylene oxalate or a polyneopentylene
oxalate; a polyC.sub.2-6alkylene succinate such as a polyethylene
succinate, a polybutylene succinate or a polyneopentylene
succinate; and a polyC.sub.2-6alkylene adipate such as a
polyethylene adipate, a polybutylene adipate or a polyneopentylene
adipate), a polyhydroxycarboxylic acid-series resin (e.g., a
polyglycolic acid, and a polylactic acid), and a polylactone-series
resin [e.g., a polyC.sub.3-12lactone-series resin such as a
polycaprolactone (e.g., "PCLH7", "PCLH4" and "PCLH1" manufactured
by Daicel Chemical Industries, Ltd.)]. The concrete examples of the
copolyester include a copolyester containing two kinds of
dicarboxylic acid components (e.g., a polyC.sub.2-4alkylene
succinate-adipate copolymer resin such as a polyethylene
succinate-adipate copolymer resin or a polybutylene
succinate-adipate copolymer resin), and a copolyester obtained from
a dicarboxylic acid component, a diol component and a lactone
(e.g., a polycaprolactone-polybutylene succinate copolymer
resin).
[0036] The polyester-series resin used in the present invention may
be a polyester-series resin containing a urethane bond (for
example, an aliphatic polyester-series resin containing a urethane
bond). The polyester-series resin containing a urethane bond
preferably includes a resin obtained from the above
polyester-series resin (e.g., a polyester diol having a low
molecular weight) and having a high molecular weight increased by a
diisocyanate compound (e.g., an aliphatic diisocyanate).
[0037] The diisocyanate compound may includes an aromatic
diisocyanate (e.g., a phenylene diisocyanate, a tolylene
diisocyanate, and diphenylmethane-4,4'-diisocyanate), an
araliphatic diisocyanate compound (e.g., a xylylene diisocyanate),
an alicyclic diisocyanate compound (e.g., isophorone diisocyanate),
an aliphatic diisocyanate compound (e.g., trimethylene
diisocyanate, tetramethylene diisocyanate, pentamethylene
diisocyanate, hexamethylene diisocyanate, lysine diisocyanatemethyl
ester, and trimethylhexamethylene diisocyanate), and others. These
diisocyanate compounds may be used singly or in combination. Among
these diisocyanate compounds, the aliphatic diisocyanate compound,
e.g., hexamethylene diisocyanate, may be preferably used.
[0038] Examples of the polyester-series resin containing a urethane
bond (e.g., an aliphatic polyester-series resin) include "BIONOLLE
#1000" series, "BIONOLLE #3000" series and "BIONOLLE #6000" series
manufactured by Showa Highpolymer Co., Ltd.
[0039] (2) Polyamide-Series Resin
[0040] The polyamide-series resin includes, for example, an
aliphatic polyamide-series resin, an alicyclic polyamide-series
resin, and an aromatic polyamide-series resin, and the aliphatic
polyamide-series resin is usually employed. These polyamide-series
resins may be used singly or in combination.
[0041] Examples of the aliphatic polyamide-series resin include a
condensate (or condensed product) of an aliphatic diamine component
(a C.sub.4-10alkylenediamine such as tetramethylenediamine or
hexamethylenediamine) and an aliphatic dicarboxylic acid component
(e.g., a C.sub.4-20alkylenedicarboxylic acid such as adipic acid,
sebacic acid or dodecanoic diacid) (for example, a polyamide 46, a
polyamide 66, a polyamide 610, a polyamide 612, a polyamide 1010, a
polyamide 1012, and a polyamide 1212); a homo- or copolymer of a
lactam (e.g., a C.sub.4-20lactam such as .epsilon.-caprolactam or
.omega.-laurolactam) or an aminocarboxylic acid (e.g., a
C.sub.4-20aminocarboxylic acid such as .omega.-aminoundecanoic
acid) (for example, a polyamide 6, a polyamide 11, and a polyamide
12); and a copolyamide having these polyamide components
copolymerized therein (for example, a polyamide 6/11, a polyamide
6/12, a polyamide 66/11, and a polyamide 66/12).
[0042] Further, the polyamide-series resin may have
biodegradability. The biodegradable polyamide-series resin may
include a polyester amide as a condensate of the aliphatic diamine
component (a C.sub.4-10alkylenediamin- e such as
tetramethylenediamine or hexamethylenediamine), the aliphatic
dicarboxylic acid component (e.g., a C.sub.4-20alkylenedicarboxylic
acid such as adipic acid, sebacic acid or dodecanoic diacid) and
the aliphatic diol component (e.g., a C.sub.2-12alkanediol such as
ethylene glycol, propylene glycol or butanediol).
[0043] (3) Polyurethane-Series Resin
[0044] The polyurethane-series resin may be obtained by a reaction
between a diisocyanate compound and a polyol compound (e.g., a diol
compound) and, if necessary, a chain-extension agent. As the
diisocyanate compound, there are exemplified an aliphatic
diisocyanate compound such as hexamethylene diisocyanate or
2,2,4-trimethylhexamethylene diisocyanate; an alicyclic
diisocyanate compound such as 1,4-cyclohexane diisocyanate or
isophorone diisocyanate; an aromatic diisocyanate compound such as
a phenylene diisocyanate, a tolylene diisocyanate,
diphenylmethane-4,4'-dii- socyanate or 1,5-naphthalene
diisocyanate; an araliphatic diisocyanate compound such as a
xylylene diisocyanate; and others.
[0045] The polyol compound includes, for example, a polyester
polyol, a polyether polyol, and a polycarbonate polyol. Among the
polyol compounds, a diol compound (e.g., a polyester diol, a
polyether diol, and a polycarbonate diol) is particularly
preferred. These polyol compounds may be used singly or in
combination.
[0046] Examples of a compound available as the diol compound
include a polyester diol (e.g., a polyester diol derived from a
C.sub.4-12aliphatic dicarboxylic acid component such as succinic
acid, adipic acid or azelaic acid, and a C.sub.2-12aliphatic diol
component ethylene glycol, propylene glycol, butanediol or
neopentyl glycol; a polyester diol derived from a C.sub.4-12lactone
component such as .epsilon.-caprolactone; and a polyester diol
derived from the aliphatic dicarboxylic acid component and/or the
aliphatic diol component, and the lactone component), a polyether
diol (e.g., a polyethylene glycol, a polypropylene glycol, a
polyoxyethylene-polyoxypropylene block copolymer, a
polyoxytetramethylene glycol, and a bisphenol A-alkylene oxide
adduct), and a polyester ether diol (e.g., a polyester diol
obtained by using the polyether diol as part of the diol
component).
[0047] Further, as the chain-extension agent, there may be used a
C.sub.2-10alkylene glycol such as ethylene glycol or propylene
glycol, and, in addition, a diamine compound [for example, an
aliphatic diamine compound (a linear or branched alkylenediamine
such as ethylenediamine, trimethylenediamine or
tetramethylenediamine; and a linear or branched
polyalkylenepolyamine such as diethylenetriamine,
triethylenetetramine, tetraethylenepentamine or
dipropylenetriamine), an alicyclic diamine compound (e.g.,
isophoronediamine), and an aromatic diamine compound (e.g.,
phenylenediamine, and xylylenediamine)]. These polyurethane-series
resins may be used singly or in combination.
[0048] (4) Poly(thio)ether-Series Resin
[0049] Examples of the poly(thio)ether-series resin include a
polyoxyalkylene-series resin, a polyphenylene ether-series resin,
and a polysulfide-series resin (polythioether-series resin). The
polyoxyalkylene-series resin includes, for example, a
polyoxyC.sub.1-4alkylene glycol such as a polyoxymethylene glycol,
a polyoxypropylene glycol, a polyoxytetramethylene glycol, or a
polyoxyethylene-polyoxypropylene block copolymer. These
poly(thio)ether-series resins may be used singly or in
combination.
[0050] (5) Polycarbonate-Series Resin
[0051] The polycarbonate-series resin includes, for example, an
aromatic polycarbonate containing a bisphenol compound (e.g.,
bisphenol A) as a base unit, and an aliphatic polycarbonate such as
diethylene glycol bisallyl carbonate. These polycarbonate-series
resins may be used singly or in combination.
[0052] (6) Polysulfone-Series Resin
[0053] Examples of the polysulfone-series resin include a
polysulfone resin obtained by polycondensation of a
dihalogenodiphenyl sulfone (e.g., dichlorodiphenyl sulfone) and a
bisphenol compound (e.g., bisphenol A or a metal salt thereof), a
polyether sulfone resin, and a polyallyl sulfone resin. These
polysulfone-series resins may be used singly or in combination.
[0054] (7) Polyolefinic Resin
[0055] The polyolefinic resin may include a homo- or copolymer of
an .alpha.-C.sub.2-6olefin, for example, a homo- or copolymer of an
olefin such as a polyethylene, a polypropylene, an
ethylene-propylene copolymer or a poly(methylpentene-1), and a
copolymer of an olefin and a copolymerizablemonomer (e.g., an
ethylene-vinylacetate copolymer, an ethylene-(meth)acrylic acid
copolymer, and an ethylene-(meth)acrylate copolymer). These
polyolefinic resins may be used singly or in combination.
[0056] (8) (Meth)acrylic Resin
[0057] As the (meth)acrylic resin, there may be mentioned a homo-
or copolymer of a (meth)acrylic monomer [e.g., (meth)acrylic acid,
a C.sub.1-18alkyl(meth)acrylate, a hydroxyalkyl(meth)acrylate, a
glycidyl(meth)acrylate, and (meth)acrylonitrile], for example, a
poly(meth)acrylate such as a poly(methyl(meth)acrylate), a methyl
methacrylate-(meth)acrylic acid copolymer, a methyl
methacrylate-acrylate-(meth)acrylic acid copolymer, a methyl
methacrylate-(meth)acrylate copolymer, and a
(meth)acrylate-styrenecopoly- mer (e.g., an MS resin). The
preferred (meth)acrylic resin includes a C.sub.1-5alkyl
poly(meth)acrylate, a methyl methacrylate-acrylate copolymer, a
(meth)acrylate-styrene copolymer (e.g., an MS resin), and others.
These (meth)acrylic resins may be used singly or in
combination.
[0058] (9) Styrenic Resin
[0059] Examples of the styrenic resin include a homo- or copolymer
of a styrenic monomer (e.g., styrene, .alpha.-methylstyrene, and
vinyl toluene) (for example, a polystyrene, a styrene-vinyl toluene
copolymer, and a styrene-.alpha.-methylstyrene copolymer), a
copolymer of a styrenic monomer and copolymerizable monomer(s) [for
example, a copolymer such as a styrene-acrylonitrile copolymer (an
AS resin), a (meth)acrylate-styrene copolymer (e.g., an MS resin),
a styrene-maleic anhydride copolymer, or a styrene-butadiene block
copolymer; a styrenic graft copolymer such as an
acrylonitrile-acrylate-styrene copolymer (an AAS resin), an
acrylonitrile-chlorinated polyethylene-styrene copolymer (an ACS
resin), or an acrylonitrile-vinyl acetate-styrene copolymer (e.g.,
an AXS resin); and a graft polymer obtained by a graft
polymerization of at least a styrenic monomer in the presence of a
rubber component, for example, a high impact polystyrene (HIPS, or
rubber-grafted polystyrenic resin), an
acrylonitrile-butadiene-styrene copolymer (an ABS resin), and an
acrylonitrile-ethylene propylene rubber-styrene copolymer (an AES
resin)]. These styrenic resins may be used singly in
combination.
[0060] (10) Vinyl-Series Resin
[0061] Examples of the vinyl-series resin include a homo- or
copolymer of a vinyl-series monomer, or a copolymer of a
vinyl-series monomer and other copolymerizable monomer. The
vinyl-series monomer includes, for example, a halogen-containing
vinyl monomer [for example, chlorine atom-containing vinyl monomer
(e.g., vinyl chloride, vinylidene chloride, and chloroprene), and a
fluorine atom-containing vinyl monomer (e.g., fluoroethylene)], and
a vinyl carboxylate [for example, a vinyl ester such as vinyl
acetate, vinyl propionate, vinyl crotonate or vinyl benzoate].
These vinyl-series resins may be used singly or in combination.
[0062] As the vinyl-series resin, for example, there may be
mentioned a vinyl chloride-series resin (e.g., a polyvinyl
chloride, a polyvinylidene chloride, a vinyl chloride-vinyl acetate
copolymer, and a vinylidene chloride-vinyl acetate copolymer), a
folurocarbon resin (e.g., a polyvinyl fluoride, a polyvinylidene
fluoride, a polychlorotrifuloroethyl- ene, a
tetrafluoroethylene-hexafluoropropylene copolymer, a
tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, and a
tetrafluoroethylene-ethylene copolymer), and a vinyl ester-series
resin (e.g., a polyvinyl acetate, a vinyl acetate-ethylene
copolymer, an ethylene-vinyl acetate copolymer, a vinyl
acetate-vinyl chloride copolymer, and a vinyl
acetate-(meth)acrylate copolymer).
[0063] As the vinyl ester-series resin, a derivative of the vinyl
ester-series resin may be also used [for example, a vinyl
alcohol-series resin (e.g., such as a polyvinyl alcohol, a
polyvinyl acetal such as a polyvinyl formal or a polyvinyl butyral,
and an ethylene-vinyl alcohol copolymer)]. Among these vinyl
alcohol-series resins, the ethylene-vinyl alcohol copolymer is
preferred. In the case of using the ethylene-vinyl alcohol
copolymer, an excessively high ethylene content of the copolymer
decreases interaction between the copolymer and the auxiliary
component (B) due to deterioration in hydrophilicity of the resin
(i.e., the copolymer). The ethylene content of the copolymer is
therefore preferred to be 10 to 40% by weight.
[0064] (11) Cellulose Derivative
[0065] Examples of the cellulose derivative include a cellulose
ester compound (e.g., a cellulose acetate, and a cellulose
phthalate), a cellulose carbamate compound (e.g., a cellulose
phenylcarbamate), and a cellulose ether compound (e.g., a
cyanoethyl cellulose). These cellulose derivatives may be used
singly or in combination.
[0066] As the cellulose ester, for example, there may be mentioned
an organic acid ester of a cellulose (or an acyl cellulose), e.g.,
a cellulose acetate (an acetyl cellulose) such as a cellulose
diacetate or a cellulose triacetate, a cellulose propionate, a
cellulose butyrate, a cellulose acetate propionate, and a cellulose
acetate butyrate; an inorganic acid ester of a cellulose such as a
cellulose nitrate, a cellulose sulfate or a cellulose phosphate;
and a mixed acid ester of a cellulose such as a cellulose nitrate
acetate.
[0067] The cellulose ether includes, for example, an alkyl
cellulose (e.g., a C.sub.2-6alkyl cellulose such as an ethyl
cellulose, an isopropyl cellulose or a butyl cellulose), an aralkyl
cellulose (e.g., a benzyl cellulose), a hydroxyalkyl cellulose
(e.g., a hydroxyC.sub.4-6alkyl cellulose such as a hydroxybutyl
cellulose), a carboxyalkyl cellulose (e.g., a carboxyC.sub.2-6alkyl
cellulose such as a carboxyethyl cellulose), and a cyanoethyl
cellulose.
[0068] In view of biodegradability, it is preferred that the
substitution degree of the cellulose derivative is low. For
example, the average substitution degree is not more than 2.5,
preferably not more than 2 (e.g., about 0.1 to 2), and more
preferably not more than 1.5 (e.g., about 0.1 to 1.5).
[0069] (12) Thermoplastic Elastomer
[0070] Examples of the thermoplastic elastomer include a
polyamide-series elastomer, a polyester-series elastomer, a
polyurethane-series elastomer, a polystyrenic elastomer, a
polyolefinic elastomer, a polyvinyl chloride-series elastomer, and
a fluorine-containing thermoplastic elastomer. These thermoplastic
elastomers may be used singly or in combination.
[0071] In the case where the thermoplastic elastomer is a block
copolymer, the block structure is not particularly limited to a
specific one, and may be a triblock structure, a multiblock
structure, a star-shaped (or astral) block structure, and
others.
[0072] The heat distortion temperature of the resin component
(e.g., a Vicat softening point defined by JIS K 7206) may be
selected from the range of 60 to 300.degree. C., and for example,
may be about 80 to 260.degree. C., preferably about 100 to
240.degree. C. (e.g., about 110 to 240.degree. C.), and more
preferably about 120 to 230.degree. C. (e.g., about 130 to
220.degree. C.). The preferred resin includes, for example, a
polyamide-series resin, a polyolefinic resin, a styrenic resin, a
vinyl-series resin (e.g., a halogen-containing resin, a vinyl
ester-series resin, and a vinyl alcohol-series resin), and a
biodegradable resin [for example, an aliphatic polyester-series
resin (e.g., a polylactic acid-series resin, and a
polyC.sub.3-12lactone-series resin), a biodegradable
polyester-series resin such as a polyesteramide, a vinyl
alcohol-series resin, and the cellulose derivative]. Incidentally,
in order to facilitate melt-kneading of the resin component with an
auxiliary component (B), a resin having a hydrophilic group such as
an amino group, a hydroxyl group or a carboxyl group may be used as
the resin component.
[0073] Since the shaped article comprising the biodegradable resin
is excellent in biodegradability, the shaped article may be useful
for example in the field of being used in natural environments
(e.g., materials for agriculture, forestry and fisheries, civil
engineering materials, construction materials, and products for
outdoor leisure activity), in the field (application) having
difficulty in recovery after use and recycle (e.g., food packaging
films, food packaging containers (or trays), sanitary goods, and
articles for everyday use), and in the field of taking advantage of
special functions of the resin (e.g., medical materials requiring
biodegradation and bioabsorbability, and covering materials
requiring sustained release).
[0074] [Water-Soluble Auxiliary Agent]
[0075] The water-soluble auxiliary agent comprises a water-soluble
auxiliary component (B) comprising at least an oligosaccharide
(B.sub.1), and is used in combination with a resin to form a
dispersed composition. Further, in order to adjust a thermal
melting property of the oligosaccharide, it is preferred that the
water-soluble auxiliary agent further comprises a plasticizing
component (B.sub.2).
[0076] (B.sub.1) Oligosaccharide
[0077] The oligosaccharide (B.sub.1) is classified broadly into two
groups: a homooligosaccharide condensed by dehydration of 2 to 10
monosaccharide molecules through glycoside linkage(s), and an
heterooligosaccharide condensed by dehydration of 2 to 10 molecules
of at least not less than two kinds of monosaccharides and/or sugar
alcohols through glycoside linkage(s). The oligosaccharide
(B.sub.1) includes, for example, a disaccharide to a
decasaccharide, and usually, an oligosaccharide of a disaccharide
to a hexasaccharide is employed. The oligosaccharide is usually a
solid at room temperatures. Incidentally, these oligosaccharides
may be an anhydrate. Moreover, in the oligosaccharide, a
monosaccharide may bond with a sugar alcohol. These
oligosaccharides may be used singly or in combination.
Incidentally, the oligosaccharide may be an oligosaccharide
composition comprising a plurality of sugar components. Such an
oligosaccharide composition is sometimes simply referred to as an
oligosaccharide.
[0078] Examples of the disaccharide include a homooligosaccharide
such as a trehalose (e.g., .alpha.,.alpha.-trehalose,
.beta.,.beta.-trehalose, and .alpha.,.beta.-trehalose), kojibiose,
nigerose, maltose, isomaltose, sophorose, laminaribiose, cellobiose
or gentiobiose; and a heterooligosaccharide such as lactose,
sucrose, palatinose, melibiose, rutinose, primeverose or
turanose.
[0079] As the trisaccharide, there may be mentioned a
homooligosaccharide such as maltotriose, isomaltotriose, panose or
cellotriose; a heterooligosaccharide such as manninotriose,
solatriose, melezitose, planteose, gentianose, umbelliferose,
lactosucrose or raffinose; and others.
[0080] Examples of the tetrasaccharide include a
homooligosaccharide such as maltotetraose or isomaltotetraose; and
a heterooligosaccharide such as stachyose, cellotetraose,
scorodose, lychnose, or a tetraose having a sugar or sugar alcohol
attached to a reducing end of panose.
[0081] Among these tetrasaccharides, the tetraose having a sugar or
sugar alcohol attached to a reducing end of panose is disclosed in,
for example, Japanese Patent Application Laid-Open No. 215892/1998
(JP-10-215892A), and includes a tetraose having a monosaccharide
(such as glucose, fructose, mannose, xylose or arabinose) or a
sugar alcohol (such as sorbitol, xylitol or erythritol) attached to
a reducing end of panose.
[0082] The pentasaccharide may include a homooligosaccharide such
as maltopentaose or isomaltopentaose; and a heterooligosaccharide
such as a pentaose having a disaccharide attached to a reducing end
of panose.
[0083] The pentaose having a disaccharide attached to a reducing
end of panose is also disclosed in, for example, Japanese Patent
Application Laid-Open No. 215892/1998 (JP-10-215892A), and includes
a pentaose having a disaccharide (such as sucrose, lactose,
cellobiose or trehalose) attached to a reducing end of panose.
[0084] Examples of the hexasaccharide include a homooligosaccharide
such as maltohexaose or isomaltohexaose.
[0085] The oligosaccharide preferably comprises at least a
tetrasaccharide from the viewpoint of a melt-kneading property with
the resin component.
[0086] The oligosaccharide may be an oligosaccharide composition
produced by decomposition of a polysaccharide. The oligosaccharide
composition usually contains a tetrasaccharide. The oligosaccharide
composition includes, for example, a starch sugar (a
saccharification product of a starch (or a saccharified starch)), a
galactooligosaccharide, a coupling sugar, a fructooligosaccharide,
a xylooligosaccharide, a soybean oligosaccharide, a chitin
oligosaccharide, and a chitosan oligosaccharide. These
oligosaccharide compositions may be used singly or in
combination.
[0087] For example, the starch sugar is an oligosaccharide
composition obtained by making an acid or glucoamylase or the like
act on a starch, and may be an oligosaccharide mixture obtained by
bonding a plurality of glucoses to each other. The starch sugar
includes, for example, a reduced starch-saccharified manufactured
by Towa Chemical Industry Co., Ltd. (brand name "PO-10", the
tetrasaccharide content is not less than 90% by weight).
[0088] The galactooligosaccharide is an oligosaccharide composition
obtained by making .beta.-galactosidase or the like act on lactose,
and may be a mixture of galactosyllactose and a
galactose-(glucose).sub.n ("n" denotes an integer of 1 to 4).
[0089] The coupling sugar is an oligosaccharide composition
obtained by making cyclodextrin synthetase (CGTase) act on a starch
and sucrose, and may be a mixture of a (glucose).sub.n-sucrose ("n"
denotes an integer of 1 to 4).
[0090] The fructooligosaccharide is an oligosaccharide composition
obtained by making fructofuranosidase act on sucrose, and may be a
mixture of a sucrose-(fructose).sub.n ("n" denotes an integer of 1
to 4).
[0091] Concerning these oligosaccharide compositions, in order to
inhibit rapid decrease of the viscosity in melt-kneading, the
content of the trisaccharide or the tetrasaccharide (in particular,
the tetrasaccharide) in the oligosaccharide composition is, for
example, not less than 60% by weight (about 60 to 100% by weight),
preferably not less than 70% by weight (about 70 to 100% by
weight), more preferably not less than 80% by weight (about 80 to
100% by weight), and particularly not less than 90% by weight
(about 90 to 100% by weight).
[0092] The oligosaccharide may be a reducing-type (maltose-type),
or a non-reducing-type (trehalose-type). The reducing-type
oligosaccharide is preferred because of excellence in heat
resistance.
[0093] The reducing-type oligosaccharide is not particularly
limited to a specific one as far as the oligosaccharide has a free
aldehyde group or ketone group to exhibit a reducing property. For
example, the reducing-type oligosaccharide includes a disaccharide
such as kojibiose, nigerose, maltose, isomaltose, sophorose,
laminaribiose, cellobiose, gentiobiose, lactose, palatinose,
melibiose, rutinose, primeverose or turanose; a trisaccharide such
as maltotriose, isomaltotriose, panose, cellotriose, manninotriose
or solatriose; a tetrasaccharide such as maltotetraose,
isomaltotetraose, cellotetraose or lychnose; a pentasaccharide such
as maltopentaose or isomaltopentaose; and a hexasaccharide such as
maltohexaose or isomaltohexaose.
[0094] Since the oligosaccharide is generally a natural
polysaccharide derivative, or a product derived from natural
product being manufactured by reducing the derivative, the
oligosaccharide can reduce the burden on the environment.
[0095] In order to disperse the resin component and the auxiliary
component effectively by kneading, it is desirable that the
oligosaccharide has a high viscosity. More specifically, in the
case where the viscosity of the 50% by weight aqueous solution of
the oligosaccharide is measured at a temperature of 25.degree. C.
by using a B-type viscometer, the viscosity is not less than 1
Pa.multidot.s (e.g., about 1 to 500 Pa.multidot.s), preferably not
less than 2 Pa.multidot.s (e.g., about 2 to 250 Pa.multidot.s, and
in particular about 3 to 100 Pa.multidot.s), more preferably not
less than 4 Pa.multidot.s (e.g., about 4 to 50 Pa.multidot.s), and
particularly not less than 6 Pa.multidot.s (e.g., about 6 to 50
Pa.multidot.s), and it is preferred to use an oligosaccharide
having a high viscosity.
[0096] Moreover, the melting point or softening point of the
oligosaccharide (B.sub.1) is preferably higher than the heat
distortion temperature (e.g., a Vicat softening point defined by
JIS K 7206) of the resin component (A). Incidentally, depending on
the kind or species of the oligosaccharide (e.g., in the case of a
starch sugar such as a reduced starch-saccharified), the
oligosaccharide is sometimes thermally decomposed without having a
melting point or softening point. In such a case, the decomposition
temperature may be considered as the "melting point or softening
point" of the oligosaccharide (B.sub.1).
[0097] The temperature difference between the melting point or
softening point of the oligosaccharide (B.sub.1) and the heat
distortion temperature of the resin component (A) is, for example,
not less than 1.degree. C. (e.g., about 1 to 80.degree. C.),
preferably not less than 10.degree. C. (e.g., about 10 to
70.degree. C.), and more preferably not less than 15.degree. C.
(e.g., about 15 to 60.degree. C.). The melting point or softening
point of the oligosaccharide (B.sub.1) may be selected from the
range of 70 to 300.degree. C. depending on the kind of the resin
component (A) and other factor(s), and may be, for example, about
90 to 290.degree. C., preferably about 100 to 280.degree. C. (e.g.,
about 110 to 270.degree. C.), and more preferably about 120 to
260.degree. C. (e.g., about 130 to 260.degree. C.). Incidentally,
an anhydride of an oligosaccharide generally has a high melting
point or softening point. For example, in the case of a trehalose,
the melting point of the dihydrate is 97.degree. C. and that of the
anhydride is 203.degree. C. In the case where the melting point or
softening point of the oligosaccharide is higher than the heat
distortion temperature of the resin component (A), the
oligosaccharide can be not only prevented from rapid deterioration
of the viscosity in melt-kneading but also inhibited from thermal
degradation.
[0098] Further, according to the present invention, the combination
of the oligosaccharide (B.sub.1) and the water-soluble plasticizing
component (B.sub.2) for plasticizing the oligosaccharide (B.sub.1)
in the water-soluble auxiliary component (B) ensures to adjust the
viscosity of the water-soluble auxiliary component (B) in kneading
with the resin component (A).
[0099] (B.sub.2) Plasticizing Component
[0100] The plasticizing component (B.sub.2) should just express a
phenomenon that the oligosaccharide (B.sub.1) hydrates to turn into
a syrup state, and may include, for example, a saccharide, and a
sugar alcohol. These plasticizing components may be used singly or
in combination.
[0101] (Saccharide)
[0102] As the saccharide, a monosaccharide and/or a disaccharide is
usually employed for plasticizing the oligosaccharide (B.sub.1)
effectively. These saccharides may be used singly or in
combination.
[0103] Examples of the monosaccharide include a triose, a tetrose,
a pentose, a hexose, a heptose, an octose, a nonose, and a decose.
These compounds may be an aldose or ketose compound, a dialdose
compound (for example, a compound which is a saccharide derivative
and has aldehyde groups in both ends of the carbon chain, such as
tetraacetylgalacto-hexod- ialdose, ido-hexodialdose or
xylo-pento-dialdose), a monosaccharide having a plurality of
carbonyl groups (e.g., an aldoalko-ketose such as osone or onose),
a monosaccharide having a methyl group (e.g., a methyl sugar such
as altromethylose), a monosaccharide having an acyl group (in
particular, e.g., a C.sub.2-4acyl group such as acetyl group) (for
example, an acetylated product of the above-mentioned aldose
compound, e.g., a acetylated product such as a pentaacetylated
product of an aldehyde glucose), a saccharide having an introduced
carboxyl group (e.g., a saccharic acid or an uronic acid), a
thiosugar, an amino sugar, a deoxy sugar, or others.
[0104] Concrete examples of such a monosaccharide include atetrose
(e.g., erythrose, and threorose), apentose (e.g., arabinose,
ribose, lyxose, deoxyribose, and xylose), and a hexose (e.g.,
allose, altrose, glucose, mannose, gulose, idose, galactose,
fructose, sorbose, fucose, rhamnose, talose, galacturonic acid,
glucuronic acid, mannuronic acid, and glucosamine).
[0105] Moreover, the monosaccharide may be a cyclic isomer having a
cyclic structure formed through a hemiacetal linkage. It is not
necessary that the monosaccharide has an optical activity (or
rotatory polarization), and the monosaccharide may be any one of
D-form, L-form, or DL-form. These monosaccharides may be used
singly or in combination.
[0106] The disaccharide is not particularly limited to a specific
one as far as the disaccharide can plasticize the oligosaccharide
(B.sub.1). For example, among the above-mentioned disaccharides,
there may be exemplified a disaccharide having a low melting point
or low softening point (e.g., gentiobiose, melibiose, and trehalose
(dehydrate)), and a disaccharide corresponding to a homo- and
heterodisaccharide of the above-mentioned monosaccharide (e.g., an
aldobiouronic acid such as glucuronoglucose in which glucuronic
acid binds to glucose through an .alpha.-1,6-glycoside
linkage).
[0107] The saccharide is, in terms of thermal stability, preferably
a reducing sugar [for example, a free monosaccharide, and in
addition, a reducing sugar having a low melting point or low
softening point (e.g., gentiobiose, and melibiose) among the
disaccharides].
[0108] (Sugar Alcohol)
[0109] As the sugar alcohol (or water-soluble polyhydric alcohol),
a linear (or chain) sugar alcohol such as an alditol (glycitol) or
a cyclic sugar alcohol such as an inositol may be used, and
usually, the linear sugar alcohol may be employed. These sugar
alcohols may be used singly or in combination.
[0110] Examples of the linear sugar alcohol include a tetrytol
(e.g., threitol, and erythritol), a pentitol [e.g.,
pentaerythritol, arabitol, ribitol (adonitol), xylitol, and
lyxitol], a hexitol [e.g., sorbitol, mannitol, iditol, gulitol,
talitol, dulcitol (galactitol), allo-dulcitol (allitol), and
altritol], a heptitol, an octitol, a nonitol, a decitol, and a
dodecitol.
[0111] Among these sugar alcohols, the preferred sugar alcohol
includes erythritol, pentaerythritol, arabitol, ribitol, xylitol,
sorbitol, dulcitol and mannitol. The sugar alcohol often comprises
at least one sugar alcohol selected from the group consisting of
erythritol, pentaerythritol and xylitol.
[0112] The plasticizing component (B.sub.2) may be a liquid (or in
a syrup state) at room temperatures (e.g., about 15 to 20.degree.
C.), and from the viewpoint of handleability and others, the
plasticizing component (B.sub.2) is usually a solid in many cases.
In the case where the auxiliary component (B) comprises the
oligosaccharide (B.sub.1) and the plasticizing component (B.sub.2),
the plasticizing component (B.sub.2) can plasticize or soften the
oligosaccharide (B.sub.1) effectively even when the oligosaccharide
(B.sub.1) is a thermally decomposable oligosaccharide not having a
clear melting point or softening point.
[0113] The melting point or softening point of the plasticizing
component (B.sub.2) is usually not more higher than the heat
distortion temperature of the resin component (A) (e.g., a Vicat
softening point defined by JIS K 7206). Incidentally, some
plasticizing components are molten at a temperature lower than the
actual melting point while having a high melting point (e.g., a
melting point of not lower than 200.degree. C.) when coexisting
with the oligosaccharide. For example, pentaerythritol exerts a
plasticizing effect on the oligosaccharide and melts at a
temperature (e.g., at about 160 to 180.degree. C.) lower than the
actual melting point (260.degree. C.). The plasticizing component
having such a high melting point cannot be utilized on its own
because of being not molten at the heat distortion temperature of
the resin component. However, such a plasticizing component can be
utilized effectively in combination with the oligosaccharide.
Incidentally, in the plasticizing component exerting a plasticizing
effect on the oligosaccharide (e.g., pentaerythritol) at a
temperature lower than the actual melting point, the temperature at
which a plasticizing effect on the oligosaccharide is exerted may
be regarded as the "melting point or softening point" of the
plasticizing component (B.sub.2).
[0114] The melting point or softening point of the auxiliary
component (B) may be not higher or lower than the heat distortion
temperature of the resin component (A). It is sufficient that the
resin component (A) and the auxiliary component (B) are molten or
soften at a temperature of at least a kneading temperature (or
fabrication temperature). For example, the temperature difference
between the melting point or softening point of the auxiliary
component (B) and the heat distortion temperature of the resin
component (A) may be selected from the range of 0 to 100.degree. C.
For example, the temperature difference may be about 3 to
80.degree. C. (e.g., about 3 to 55.degree. C.), preferably about 5
to 60.degree. C. (e.g., about 5 to 45.degree. C.), and more
preferably about 5 to 40.degree. C. (e.g., about 10 to 35.degree.
C.). Incidentally, in the case where the temperature difference
between the melting point or softening point of the auxiliary
component (B) and the heat distortion temperature of the resin
component (A) is small (e.g., in the case where the temperature
difference is about 0 to 20.degree. C.), there is an advantage that
the dispersion shape can be fixed in a short time by an auxiliary
component (B) having a high solidification rate (e.g., a sugar
component).
[0115] Further, the melt flow rate of the auxiliary component (B)
(e.g., an auxiliary component comprising the oligosaccharide
(B.sub.1) and the plasticizing component (B.sub.2)) may be, for
example, when measured is the melt flow rate defined by JIS K 7210
at a temperature 30.degree. C. higher than the heat distortion
temperature of the resin component (A) (e.g., the Vicat softening
point), not less than 1 (e.g., about 1 to 40), preferably not less
than 5 (e.g., about 5 to 30), and more preferably not less than 10
(e.g., about 10 to 20).
[0116] In the auxiliary component (B), the ratio (weight ratio) of
the plasticizing component (B.sub.2) is selected from the range
that the plasticizing component can plasticize the oligosaccharide
(B.sub.1) efficiently without localizing by aggregation or other
reason accompanying melt-kneading. For example, the ratio of the
oligosaccharide (B.sub.1) relative to the plasticizing component
(B.sub.2) [the oligosaccharide (B.sub.1)/the plasticizing component
(B.sub.2)] may be selected from 99/1 to 50/50, and may be
preferably about 95/5 to 60/40 and more preferably about 90/10 to
70/30.
[0117] The compatibility between the resin component (A) and the
auxiliary component (B) is not particularly limited to a specific
one. The resin component (A) and the auxiliary component (B) may be
incompatible or compatible with each other. In the case where the
resin component and the auxiliary component are compatible with
each other, the resin component and the auxiliary component can be
phase-separated from each other due to differences in surface
tension and solidification rate between the resin component and the
auxiliary component in a cooling process after kneading even when
the resin component and the auxiliary component forms a uniform and
single phase at a kneading temperature. The resin component and the
auxiliary component can be phase-separated from each other even in
the case of having compatibility because the auxiliary component of
the present invention has a low surface tension and can maintain a
relatively high viscosity even at a temperature for kneading with
the resin component, and in addition has a unique property that is
extremely high solidification rate on cooling compared with the
resin component because of low in the molecular weight.
[0118] The ratio (weight ratio) of the resin component (A) relative
to the auxiliary component (B) may be selected depending on the
kinds or viscosities of the resin component and the auxiliary
component, the compatibility between the resin component and the
auxiliary component, or other factor(s), and is not particularly
limited to a specific one. The ratio [the resin component (A)/the
auxiliary component (B)] may be usually selected from the range
that formability of the dispersed composition is not impaired, for
example, a broad range such as about 99/1 to 1/99. For example, the
ratio is about 90/10 to 5/95, preferably about 80/20 to 10/90
(e.g., about 80/20 to 15/85), and more preferably 75/25 to 25/75
(in particular, about 60/40 to 25/75).
[0119] Incidentally, in the case where a shaped article (resinous
shaped article) obtained from the dispersed composition is a porous
one, the ratio (weight ratio) of the resin component (A) relative
to the auxiliary component (B) [the resin component (A)/the
auxiliary component (B)] may be selected from the range of 75/25 to
10/90. For example, in view of keeping a balance between porosity
and mechanical strength, the ratio is preferably about 60/40 to
15/85 (e.g., about 50/50 to 15/85), and more preferably about 40/60
to 25/75. For example, when the ratio [(A)/(B)] (weight ratio) is
about 40/60 to 25/75, the porous resinous shaped article is useful
as a separation membrane.
[0120] Moreover, in the case where a shaped article (resinous
shaped article) obtained from the dispersed composition is a
particulate, the ratio (weight ratio) of the resin component (A)
relative to the auxiliary component (B) [the resin component
(A)/the auxiliary component (B)] is usually about 55/45 to 1/99,
preferably about 50/50 to 5/95, and more preferably about 45/55 to
10/90.
[0121] [Other Additive]
[0122] The dispersed composition or the resin composition may
comprise, if necessary, various additives, for example, a filler, a
plasticizer or a softener, a lubricant, a stabilizer (e.g., a heat
stabilizer, an antioxidant, and an ultraviolet ray absorbing
agent), a thickener, a coloring agent (e.g., a titanium oxide, and
a carbon black), a dispersing agent, a flame retardant, and a
antistatic agent.
[0123] The filler (or reinforcer) includes, for example, a
particulate filler or reinforcer (e.g., a mica, a clay, a talc, a
silicate compound, a silica, calcium carbonate, magnesium
carbonate, a carbon black, and a ferrite), and a fibrous filler or
reinforcer (e.g., an organic fiber such as a rayon, a nylon, a
vinylon or an aramid, and an inorganic fiber such as a carbon
fiber, a glass fiber, a metal fiber or a whisker).
[0124] In these additives, the amount of each additive may be an
effective amount, and for example, the total amount of the
additives may be about 0 to 50 parts by weight, preferably about
0.1 to 20 parts by weight and more preferably about 0.5 to 10 parts
by weight, relative to 100 parts by weight of the resin. Moreover,
relative to 100 parts by weight of the resin, the amount of each
additive may be about 0 to 30 parts by weight, preferably about
0.05 to 20 parts by weight, and more preferably about 0.1 to 10
parts by weight.
[0125] In the dispersed composition or the resin composition of the
present invention, the phase separation structure or the dispersion
structure is not particularly limited to a specific one, and the
resin component and the auxiliary component may form an
islands-in-the-sea structure or a complex structure of the
dispersed phase, or the both components may form a continuous
phase, respectively. In the case where the auxiliary component (B)
forms a continuous phase in an islands-in-the-sea structure (a
phase separation structure having an independent resin phase) or in
a bicontinuous phase, the auxiliary component can be eluted
quickly.
[0126] In the case where the auxiliary component (B) forms the
continuous phase in an islands-in-the-sea structure, the
conformation (or shape) of the dispersed phase comprising the resin
component may be a particle shape (e.g., a spherical shape, an
elliptical shape, a polyhedral shape, a prismatic shape, a columnar
(or cylindrical) shape, a rod-like shape, and an amorphous shape),
and others. The preferred shape of the dispersed phase is a
spherical shape. Incidentally, the average particle size of the
dispersed phase is not particularly limited to a specific one, and
may be selected from the range of about 0.1 .mu.m to 1 mm as usage.
For example, the average particle size is about 0.1 to 800 .mu.m
(e.g., about 0.1 to 500 .mu.m), preferably about 0.1 to 100 .mu.m
(e.g., about 0.5 to 80 .mu.m), and more preferably about 0.5 to 50
.mu.m (e.g., about 1 to 40 .mu.m).
[0127] When the auxiliary component (B) and the resin component (A)
form a bicontinuous phase, the conformation (or shape) of a
continuous phase comprising the auxiliary component (pore-forming
agent) may be a lamellar structure, an OBDD (Ordered Bicontinuous
Double Diamond) structure, a cylinder structure, and others. In the
case of measuring the size of the continuous phase having such a
structure, a conventional measuring method such as a conversion
into the size of a circle cannot be used due to absence of an
independent unit (such as a particle unit). In such a case, the
size of the continuous phase comprising the auxiliary component can
be determined, for example, by measuring the minimum length (X) in
the width direction of the phase in one continuous phase (or
tetrapod-shaped base unit) for one cross section of the dispersed
composition. Further, by measuring the length (X) in each of a
plurality of the phases (or base units) selected at random, the
average value of the length (X) can be calculated. The average
length (X) is not particularly limited to a specific one, and may
be selected from the range of about 0.1 .mu.m to 1 mm as usage. For
example, the average length (X) is about 0.1 to 800 .mu.m (e.g.,
about 0.1 to 500 .mu.m), preferably about 0.1 to 100 .mu.m (e.g.,
about 0.5 to 80 .mu.m), and more preferably about 0.5 to 50 .mu.m
(e.g., about 1 to 40 .mu.m).
[0128] [Production Process of Shaped Article]
[0129] The present invention also includes a process comprising
eluting the auxiliary component (B) from the dispersed composition
for producing a shaped article (e.g., a porous material, or a
particle) comprising a resin component (A).
[0130] The dispersed composition may be prepared by kneading the
resin component (A) with auxiliary component (B), and usually, the
kneaded composition is often shaped to prepare a preliminary shaped
article. The kneading operation may be carried out by using a
conventional kneading machine (e.g., a uniaxial or biaxial screw
extruder, a kneader, and a calender roll). The kneading time may
be, for example, selected from the range of 10 seconds to one hour,
and is usually about 30 seconds to 45 minutes, and preferably about
1 to 30 minutes (e.g., 1 to 10 minutes). Moreover, in advance of
kneading, the resin component and the auxiliary component may be
preliminarily converted into a powder form by a machine such as a
freeze grinder or may be preliminarily kneaded by a Henschel mixer,
a tumbler mixer, a ball mill or others.
[0131] Examples of the shaping (or molding) method include an
extrusion molding, an injection molding, a blow molding, and a
calender molding. In view of productivity or easiness of
processing, an extrusion molding or an injection molding is usually
applied. The shape of the preliminary shaped article is not
particularly limited to a specific one, and may be a
zero-dimensional shape (e.g., a particle shape, and a pellet
shape), a one-dimensional shape (e.g., a strand shape, and a rod or
bar shape), a two-dimensional shape (e.g., a plate shape, a sheet
shape, and a film shape), a three-dimensional shape (e.g., a
tubular shape, and a block shape), and others. Considering the
elution property (or elution capability) of the auxiliary
component, it is desirable to process (or shape) the dispersed
composition into a strand shape, a rod or bar shape, a sheet shape,
or a film shape. Moreover, the preliminary shaped article may be
processed by laminating other base material in the shaping (or
molding) process.
[0132] Incidentally, it is possible to set the kneading temperature
or processing (shaping) temperature (or fabrication temperature)
appropriately depending on a raw material to be used (e.g., the
resin component and the auxiliary component). For example, the
kneading temperature or processing temperature is about 90 to
300.degree. C., preferably about 110 to 260.degree. C., more
preferably about 140 to 240.degree. C. (e.g., about 170 to
240.degree. C.), and particularly about 170 to 230.degree. C.
(e.g., about 180 to 220.degree. C.). In order to avoid thermal
decomposition of the auxiliary component (the oligosaccharide and
the plasticizing component), the kneading temperature or the
processing temperature may be set to a temperature not higher than
230.degree. C.
[0133] The disperse system (a form in which the resin component and
the auxiliary component are dispersed) may be formed by cooling a
molten mixture (e.g., a kneaded matter, and a preliminary shaped
article) of the resin component and the auxiliary component
appropriately after kneading and/or processing (shaping or
fabrication). For example, the cooling temperature may be at least
about 10.degree. C. lower than the heat distortion temperature of
the resin component, or the melting point or softening point of the
auxiliary component, and e.g., may be about 10 to 100.degree. C.
lower than the above temperature (the heat distortion temperature
of the resin component, or the melting point or softening point of
the auxiliary component), preferably about 15 to 80.degree. C.
lower than the above temperature, and more preferably about 20 to
60.degree. C. lower than the above temperature. Specifically, for
example, the cooling temperature may be selected from the range of
5 to 150.degree. C. depending on the kind of the resin component or
the auxiliary component, and may be, e.g., about 10 to 120.degree.
C. (e.g., about 10 to 60.degree. C.), preferably about 15 to
100.degree. C. (e.g., about 15 to 50.degree. C.), and more
preferably about 20 to 80.degree. C. (e.g., about 20 to 40.degree.
C.). The cooling time may be suitably set according to the kind of
the resin component or the auxiliary component, the cooling
temperature, and others, and may be selected, for example, from the
broad range of 30 seconds to 20 hours. For example, the cooling
time may be about 45 seconds to 10 hours, preferably about one
minute to 5 hours (e.g., about one minute to one hour), and more
preferably about 1.5 to 30 minutes. Even in the case where the
resin component and the auxiliary component are compatible with
each other, the disperse system can be formed by cooling due to
differences in surface tension and solidification (such as
crystallization) rate between the resin component and the auxiliary
component in the cooling step, and a dispersed composition can be
obtained.
[0134] For example, in the case of producing a porous material or a
particle, the average pore size of the porous material or the
average particle size of the particle may be changed by adjusting
the compatibility between the resin component and the auxiliary
component, the melt viscosity of the resin component and the
auxiliary component, the kneading conditions (e.g., the kneading
time, and the kneading temperature), the processing (or shaping)
temperature, and the cooling conditions (e.g., the cooling time,
and the cooling temperature), so that a porous material having not
only a high porosity but also a very high uniformity in pore size
(in particular, a porous material having an open pore (or cell)),
or a particle having a narrow particle size distribution range and
a uniform particle size can be obtained conveniently. Moreover, the
form of the object matter can be changed by adjusting the
above-mentioned conditions (e.g., the viscosity, and the cooling
conditions). For example, even a system having a determined
formulation in the resin component and the auxiliary component may
selectively form a porous material or a particle depending on these
conditions.
[0135] The average pore size of the porous material or the average
particle size of the particle may be selected from the range of
about 0.1 .mu.m to 1 mm as usage without being limited to a
specific one, and is, for example, about 0.1 to 800 .mu.m (e.g.,
about 0.1 to 500 .mu.m), preferably about 0.1 to 100 m (e.g., about
0.5 to 80 .mu.m), and more preferably about 0.5 to 50 .mu.m (e.g.,
about 1 to 40 .mu.m).
[0136] Moreover, the coefficient of variation of the pore size
([the standard deviation of the pore size/the average pore
size].times.100) or the coefficient of variation of the particle
size ([the standard deviation of the particle size/the average
particle size].times.100) is not more than 60 (e.g., about 5 to
60), and more preferably not more than 50 (e.g., about 10 to
50).
[0137] The preliminary shaped article (or dispersed composition)
obtained by the above-mentioned manner may be immersed in a solvent
[for example, water, a water-soluble solvent (e.g., an alcohol
compound (such as methanol, ethanol, propanol, isopropanol, or
butanol), and an ether compound (such as a cellosolve or a butyl
cellosolve))] to elute or wash out the auxiliary component, and a
shaped article may be obtained accordingly. The preferred solvent
is water because of the low burden on the environment and the
industrial cost reduction. The elution of the auxiliary component
may be conducted by a conventional manner, for example under an
atmospheric pressure (e.g., about one atom or 100,000 Pa), a
reduced pressure, or an elevated pressure. The elution temperature
of the auxiliary component may be appropriately set depending on
the resin component and the auxiliary component, and is, for
example, about 10 to 100.degree. C., preferably about 25 to
90.degree. C., and more preferably 30 to 80.degree. C. (e.g., about
40 to 80.degree. C.). Since the water-soluble auxiliary component
of the present invention is easily soluble in water, a large amount
of water is not required.
[0138] The shaped article may be collected by a collecting method
such as filtration or centrifugation. It is desirable that the
obtained shaped article has no residual auxiliary component.
However, the small amount of the residual auxiliary component in
the shaped article does not significantly affect the shaped article
because the auxiliary component is a compound derived from a
natural product, in view of cost reduction of the washing
process.
[0139] Incidentally, the auxiliary component extracted with the
solvent may be conveniently collected by a conventional separating
means (e.g., distillation, concentration, and
recrystallization).
[0140] The above-mentioned shaped article is not particularly
limited to a specific one as far as the shaped article is obtained
by eluting the auxiliary component from the resin component, and
for example, includes a porous material (e.g., a porous material
having a two-dimensional structure such as a sheet shape or a film
shape) or a particle (e.g., a particle having a spherical (or round
or ball-like) shape or a fine spherical shape). Incidentally, the
obtained shaped article may be processed by laminating other base
material by a thermal fusing or other means.
[0141] According to the present invention, the use of a
water-soluble auxiliary component (or a water-soluble auxiliary
agent) being a saccharide yet kneadable with a resin uniformly
ensures to produce a dispersed composition comprising the
water-soluble auxiliary component and the resin component (or a
resin composition for forming a disperse system). Moreover, even in
the case of using a wide kind of the resin component, the present
invention ensures not only to form a shaped article having a given
shape with industrial advantage, but also to form a dispersed
composition kneadable even in containing an auxiliary component in
a high proportion relative to a resin component and having a
uniform phase-separation structure. Further, the water-soluble
auxiliary component can be eluted from the dispersed composition
with water, and additionally, even in the case of discarding the
eluted liquid eluate as a waste fluid, the water-soluble auxiliary
component has no adverse affect on the environment because of being
derived from a natural product.
INDUSTRIAL APPLICABILITY
[0142] The shaped article obtained by the production process of the
present invention may be used for various applications depending on
the given shape. For example, the porous material may be utilized
for a separation membrane for liquid, a filter, a moisture
absorbent, an adsorbent, a humectant, or an image-receiving layer
(or image-receiver) for recording sheet (e.g., a receiver for an
image of ink).
[0143] Moreover, with respect to the particle obtained by the
present invention, since the wide-ranging kind of resin can be
applied for the particle, the present invention can be used for
improving the easiness of a particle to be mixed with other fine
particle (e.g., an inorganic fine particle). In addition, the
particle may be used as a coating material or a coating agent
(e.g., a powdered paint), a blocking inhibitor (e.g., a blocking
inhibitor for a shaped article), a spacer, a toner, and others.
Further, the particle may be also used as an additive for daily
commodity (such as a cosmetic preparation), an additive for sheet
or film, and others.
EXAMPLES
[0144] The following examples are intended to describe this
invention in further detail and should by no means be interpreted
as defining the scope of the invention.
Examples 1 to 5 and Comparative Examples 1 to 3
[0145] In each Examples or Comparative Examples, a resin
composition comprising a resin component and an auxiliary component
in formulation shown in Table 1 was melt-kneaded at a preset
temperature of 200.degree. C. for 5 minutes by using a brabender
(manufactured by Toyo Seiki Seisaku-sho, Ltd., laboplastmill), and
then was allowed to stand at 30.degree. C. for 10 minutes.
Thereafter, the kneaded matter was pressed at 200.degree. C. for 3
minutes under a pressure of 200 kg/cm (about 20 MPa) by using a
pressing machine to produce a plate-like dispersed composition
having a thickness of 1 mm. The dispersed composition was quickly
cooled at 30.degree. C. for 3 minutes under a pressure of 200 kg/cm
(about 20 MPa), and then immersed in hot water of 60.degree. C. The
dispersed composition was allowed to stand until the content of the
auxiliary component was reduced to about 5% by weight of the
initial content, and a porous material was finally produced.
Incidentally, each component used and evaluation methods of the
obtained porous material are described below. The results are shown
in Table 1.
[0146] (Resin Component)
[0147] Resin-1: Ethylene-vinyl alcohol copolymer resin
(manufactured by Kuraray Co., Ltd., "EP-L101B", ethylene content:
19.8% by weight)
[0148] Resin-2: Polystyrene resin (manufactured by Toyo Styrene
Co., Ltd., "GPPS HRM63C")
[0149] Resin-3: Polypropylene resin (manufactured by Grand Polymer
Co., Ltd., "F219D")
[0150] (Auxiliary Component)
[0151] Auxiliary component-1 (oligosaccharide): Starch sugar
(manufactured by Towa Chemical Industry Co., Ltd., a reduced
starch-saccharified "PO-10", a viscosity of a 50% by weight aqueous
solution measured at 25.degree. C. by a B-type viscometer: 6.5
Pa.multidot.s)
[0152] Auxiliary component-2 (plasticizing component): Sugar
alcohol (manufactured by Wako Pure Chemical Industries, Ltd.,
pentaerythritol)
[0153] Auxiliary component-3 (plasticizing component): Sugar
alcohol (manufactured by Mitsubishi-Kagaku Foods Corporation,
erythritol)
[0154] (Measurement Method of Pore Size)
[0155] FIG. 1 shows a SEM photograph of cross section of a porous
material obtained in Example 2. As shown in FIG. 1, in the case
where the cross sectional structure of the porous material is a
pore structure having a three-dimensional continuity of the pores,
there is no closed pore and accordingly a conventional pore-size
measuring method such as a conversion into the size of a circle
cannot be adopted. Therefore, in an area corresponding to one pore
in a photograph of the cross section of the porous material taken
at 100 to 10000 magnifications by a scanning electron microscope
(SEM: manufactured by JEOL Ltd.), the minimum length in the width
direction of the pore was considered as a pore size. In the
obtained pore material, 100 pores were selected at random and
respective pore sizes were measured to calculate the average pore
size, the standard deviation, and the coefficient of variation.
Further, the presence or absence of a pore having a pore size over
100 .mu.m was inspected.
1 TABLE 1 Comparative Examples Examples 1 2 3 4 5 1 2 3 Resin
component 1 30 30 30 -- -- 30 30 -- (% by weight) 2 -- -- -- 30 --
-- -- 30 3 -- -- -- -- 30 -- -- -- Auxiliary 1 70 50 49 50 50 -- --
-- component 2 -- 20 19 20 20 70 50 70 (% by weight) 3 -- -- 2 --
-- -- 20 -- Average pore size 2 12 28 22 24 48 -- 96 (.mu.m)
Standard deviation 0.8 4.7 9.8 10.7 11.4 42 -- 120 (.mu.m)
Coefficient of 40 39 35 49 48 88 -- 125 variation Pore having pore
size none none none none none present -- present over 100 .mu.m
[0156] As apparent from Table 1, in each of Examples 1 to 5, a
porous material having a coefficient of variation of not more than
60 and a high uniformity in pore size was obtained.
[0157] In Comparative Examples 1 and 3, the presence of aggregated
massive pentaerythritol was visually confirmed apparently in the
resinous shaped article after melt-kneading, and pores having a
pore size over 100 .mu.m were scattered over the obtained porous
material. Moreover, in Comparative Example 2, erythritol molten
during the melt-kneading step was separated from the resin
component completely. Therefore, it was impossible to obtain a
uniform mixing state and give a porous material.
Examples 6 to 19 and Comparative Examples 4 and 5
[0158] A dispersed composition was produced from a resin component
and an auxiliary component having a formulation shown in Table 2 in
the same manner as in Example 1. The obtained dispersed composition
was quickly cooled at 30.degree. C. for 3 minutes under a pressure
of 200 kg/cm (about 20 MPa), and then immersed in hot water of
60.degree. C. to give a suspension of a resin particle. The
insoluble matter was separated from the suspension by using a
membrane (pore size: 0.45 .mu.m) made of a polyvinylidene fluoride
to collect the fine particle of the resin. Incidentally, each
component used, compatibility, and evaluation methods of the
obtained porous material are described below. The results are shown
in Table 2.
[0159] (Resin Component)
[0160] Resin-4: Nylon 12 (polyamide 12) resin (manufactured by
Daicel-Degussa Ltd., "DIAMID L1600")
[0161] Resin-5: Polystyrene resin (manufactured by Toyo Styrene
Co., Ltd., "GPPS HRM63C")
[0162] Resin-6: Cellulose acetate butyrate resin (manufactured by
Eastman Chemical Company, "CAB171-15S")
[0163] Resin-7: Styrene-butadiene copolymer resin (manufactured by
Phillips Petroleum International Ltd., "K RESIN KK38")
[0164] Resin-8: Polyvinylidene fluoride resin (manufactured by
Solvay Advanced Polymers K.K., "PVDF6008")
[0165] Resin-9: Polylactic acid (manufactured by Mitsui Chemicals,
Inc., "LACEA H-100PL")
[0166] Resin-10: Polycaprolactone-polybutylene succinate copolymer
resin (manufactured by Daicel Chemical Industries, Ltd., "CELLGREEN
CBS201")
[0167] Resin-11: Ethylene-vinyl alcohol copolymer resin
(manufactured by Kuraray Co., Ltd., "EP-L101B", ethylene content:
19.8% by weight)
[0168] (Auxiliary Component)
[0169] Auxiliary component-4 (oligosaccharide): Starch sugar
(manufactured by Towa Chemical Industry Co., Ltd., a reduced
starch-saccharified "PO-10", a viscosity of a 50% by weight aqueous
solution measured at 25.degree. C. by a B-type viscometer: 6.5
Pa.multidot.s)
[0170] Auxiliary component-5 (a) (plasticizing component): Sugar
alcohol (manufactured by Wako Pure Chemical Industries, Ltd.,
pentaerythritol)
[0171] Auxiliary component-5 (b) (plasticizing component): Sugar
alcohol (manufactured by Wako Pure Chemical Industries, Ltd.,
D(-)sorbitol)
[0172] (Evaluation of Compatibility Between Resin Component and
Auxiliary Component)
[0173] In order to evaluate whether or not the resin component and
the auxiliary component were compatible with each other at the
kneading temperature, a thermal analysis by a differential scanning
calorimetry (DSC) was used. The method is detailed below.
[0174] As a measuring apparatus, a differential scanning
calorimeter (DSC: manufactured by Shimadzu Corporation, "DSC600E")
was used. A resin component and an auxiliary component having a
mixing ratio shown in Table 2 were pre-kneaded at a kneading
temperature (200.degree. C.) for 5 minutes by using a brabender
(manufactured by Toyo Seiki Seisaku-sho, Ltd., laboplastmill) to
give a sample. The sample was subjected to the measuring apparatus,
and once heated to 200.degree. C., allowed to stand for 5 minutes.
Then, based on JIS K7121, a temperature at the peak top of the
exothermic peak upon crystallization of the resin component
obtained at a cooling rate of 10.degree. C./minute was read to
determine a crystallization temperature of the resin component.
Moreover, the same operation was conducted to the resin component,
and the crystallization temperature of the resin component alone
was determined.
[0175] In a crystalline resin component, when the crystallization
temperature of the resin component alone was compared with that of
the resin component determined by using the mixture of the resin
component and the auxiliary component and the temperature
difference was not more than 1.degree. C., it was judged that the
resin component and the auxiliary component had compatibility with
each other.
[0176] In the case where the resin component was an amorphous
resin, it was impossible to measure the crystallization temperature
of the resin component. Therefore, the crystallization temperature
of the oligosaccharide determined by the above-mentioned manner for
the auxiliary component was compared with the crystallization
temperature of the oligosaccharide determined for a mixture of the
resin component and the auxiliary component. The temperature
difference of the resin component and the auxiliary component was
not more than 1.degree. C., it was judged that the resin component
and the auxiliary component had compatibility with each other.
[0177] (Number Average Particle Size of Resin Particle)
[0178] The collected resinous fine particle was dried, and then the
configuration (or shape) of the fine particle was observed by using
a scanning electron microscope. Moreover, the appropriate amount of
the dry resin fine particle was dispersed in pure water again to
prepare a suspension. Then, the number average particle size of the
resinous fine particle was determined by using a laser diffraction
particle size analyzer (manufactured by Shimadzu Corporation,
"SALD-2000J"). Moreover, concerning the resinous fine particle, the
standard deviation and the coefficient of variation relative to 100
particles selected at random were calculated.
[0179] (Effect on Environment)
[0180] The effect on environment was evaluated on the basis of the
following criteria.
[0181] "A": auxiliary component comprises only a compound derived
from a natural product.
[0182] "B": the auxiliary component comprises a compound derived
from a natural product and an industrial product having a low
molecular weight.
2 TABLE 2 Resin Auxiliary Auxiliary Number average Coefficient
Effect component component 4 component 5 particle size of on
Examples (wt %) (wt %) (wt %) Compatibility (.mu.m) variation
environment Example 6 4 (30%) 50% a (20%) compatible 11 47 B
Example 7 4 (40%) 48% a (12%) compatible 6.2 38 B Example 8 4 (30%)
50% b (20%) compatible 28 58 A Example 9 4 (20%) 60% b (20%)
compatible 7.6 41 A Example 10 5 (30%) 50% a (20%) incompatible 34
53 B Example 11 5 (30%) 50% b (20%) incompatible 48 58 A Example 12
5 (30%) 55% b (15%) incompatible 12 45 A Example 13 6 (30%) 50% a
(20%) incompatible 5.8 29 B Example 14 7 (30%) 50% a (20%)
incompatible 18 47 B Example 15 8 (30%) 50% a (20%) incompatible 56
55 B Example 16 9 (30%) 50% a (20%) incompatible 3.3 28 B Example
17 10 (30%) 50% a (20%) incompatible 8.2 32 B Example 18 10 (30%)
50% b (20%) incompatible 24 34 A Example 19 11 (15%) 65% b (20%)
compatible 22 33 A Comparative 5 (30%) -- a (70%) incompatible --
-- B Example 4 Comparative 4 (30%) -- b (70%) compatible -- -- A
Example 5 Auxiliary component 5: (a: pentaerythritol, b:
D(-)sorbitol)
[0183] In Examples 6 to 19, whether the resin component and the
auxiliary component were compatible or incompatible with each
other, a spherical resinous fine particle having a fine spherical
shape could be obtained. For the purpose of reference, FIG. 2 shows
an electron micrograph of a spherical fine particle of a cellulose
acetate butyrate resin obtained in Example 13.
[0184] Moreover, in Comparative Example 4 using pentaerythritol, as
an auxiliary component, which was a sugar alcohol not plasticized
completely at the heat distortion temperature of the resin
component, even when the dispersed composition obtained by
melt-kneading was immersed in water to remove the auxiliary
component, the resin component was not made into a fine particle
and a sponge-like massive product possessing a pore having a pore
size over 100 .mu.m was obtained.
[0185] Further, in Comparative Example 5 using sorbitol, as an
auxiliary component, which was a sugar alcohol having a melting
point lower than the heat distortion temperature of the resin
component, it was impossible to knead the auxiliary component with
the resin component because of a too low viscosity of the auxiliary
component in melt-kneading.
* * * * *