U.S. patent application number 14/672635 was filed with the patent office on 2015-10-01 for curable composition and shaped product.
This patent application is currently assigned to DAICEL CORPORATION. The applicant listed for this patent is DAICEL CORPORATION. Invention is credited to Nobuhiko HARADA, Shinji KIKUCHI.
Application Number | 20150275043 14/672635 |
Document ID | / |
Family ID | 54161207 |
Filed Date | 2015-10-01 |
United States Patent
Application |
20150275043 |
Kind Code |
A1 |
KIKUCHI; Shinji ; et
al. |
October 1, 2015 |
CURABLE COMPOSITION AND SHAPED PRODUCT
Abstract
A curable composition comprises a cationic curable silicone
resin and a leveling agent, the cationic curable silicone resin
comprises a silsesquioxane unit, has a monomer unit having an epoxy
group in a proportion of not less than 50% by mol in a total
monomer unit, and has a number average molecular weight of 1000 to
3000.
Inventors: |
KIKUCHI; Shinji;
(Amagasaki-shi, JP) ; HARADA; Nobuhiko;
(Amagasaki-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
DAICEL CORPORATION |
Osaka |
|
JP |
|
|
Assignee: |
DAICEL CORPORATION
Osaka
JP
|
Family ID: |
54161207 |
Appl. No.: |
14/672635 |
Filed: |
March 30, 2015 |
Current U.S.
Class: |
428/220 ;
428/447; 524/858 |
Current CPC
Class: |
Y10T 428/31663 20150401;
C09D 183/04 20130101; C09D 5/16 20130101; C09D 183/06 20130101;
C09D 7/47 20180101; C09D 5/00 20130101; C08G 77/14 20130101 |
International
Class: |
C09D 183/04 20060101
C09D183/04; C09D 7/06 20060101 C09D007/06; C09D 5/00 20060101
C09D005/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 31, 2014 |
JP |
2014-072693 |
Claims
1. A curable composition comprising a cationic curable silicone
resin and a leveling agent, wherein the cationic curable silicone
resin comprises a silsesquioxane unit, has a monomer unit having an
epoxy group in a proportion of not less than 50% by mol in a total
monomer unit, and has a number average molecular weight of 1000 to
3000.
2. A curable composition according to claim 1, wherein the cationic
curable silicone resin has a silsesquioxane unit represented by the
formula (1): R.sup.1SiO.sub.3/2 wherein R.sup.1 represents a group
comprising an epoxy group; a hydrogen atom; or a hydrocarbon group;
in a proportion of not less than 50% by mol in the total monomer
unit constituting the cationic curable silicone resin.
3. A curable composition according to claim 1, wherein the cationic
curable silicone resin further comprises a unit represented by the
formula (2): R.sup.1SiO(OR.sup.2) wherein R.sup.1 represents a
group comprising an epoxy group; a hydrogen atom; or a hydrocarbon
group; and R.sup.2 represents a hydrogen atom or a C.sub.1-4alkyl
group; and has a molar ratio of the silsesquioxane unit relative to
the unit represented by the formula (2) of not less than 5.
4. A curable composition according to claim 1, wherein the
silsesquioxane unit comprises a unit represented by the formula
(3): R.sup.3SiO.sub.3/2 wherein R.sup.3 represents a group
comprising an alicyclic epoxy group, and a unit represented by the
formula (4): R.sup.4SiO.sub.3/2 wherein R.sup.4 represents an aryl
group which may have a substituent.
5. A curable composition according to claim 1, wherein the cationic
curable silicone resin has a molecular weight distribution Mw/Mn of
1 to 3.
6. A curable composition according to claim 1, wherein the leveling
agent comprises at least one of a silicone-series leveling agent
and a fluorine-containing leveling agent, and the leveling agent
has at least one of a reactive group to an epoxy group, and a
hydrolytically condensable group.
7. A curable composition according to claim 1, wherein the leveling
agent has a proportion of 0.1 to 10 parts by weight relative to 100
parts by weight of the cationic curable silicone resin.
8. A curable composition according to claim 1, wherein the leveling
agent comprises a silicone-series leveling agent having a hydroxyl
group, and the leveling agent has a proportion of 0.5 to 5 parts by
weight relative to 100 parts by weight of the cationic curable
silicone resin.
9. A shaped product comprising a hardcoat layer, wherein the
hardcoat layer is a cured product of a curable composition recited
in claim 1.
10. A shaped product according to claim 9, which comprises the
hardcoat layer alone and has an average thickness of 10 to 200
.mu.m.
11. A shaped product according to claim 9, which further comprises
a transparent substrate layer, wherein the transparent layer has a
side provided with the hardcoat layer.
12. A shaped product according to claim 10, which is produced by a
roll-to-roll system.
13. A shaped product according to claim 9, which comprises the
hardcoat layer and a three-dimensional base.
Description
TECHNICAL FIELD
[0001] The present invention relates to a curable composition (a
hardcoat liquid or a hardcoat agent) useful for a hardcoat film
having desired abrasion resistance, transparency, or other
properties or a hardcoat sheet as a glass substitute. The present
invention also relates to a shaped product obtainable by curing the
composition.
BACKGROUND ART
[0002] Glass is known as a material having a very large surface
hardness. For example, a glass having a surface pencil hardness
increased to 9H by an alkali ion exchange treatment is also known.
Unfortunately, the alkali ion exchange treatment of glass, which
produces alkali waste fluids in large quantities, has a large
burden on the environment. Further, the glass is fragile due to a
large specific gravity and a low flexibility thereof. Thus since
the glass fails to be produced or processed by a roll-to-roll
system and is necessarily produced or processed in the form of a
sheet, the production efficiency is low.
[0003] A plastic material, such as a polyester, has an excellent
flexibility, although the plastic material has a small surface
hardness. Thus the plastic material is easily scratched and has a
low abrasion resistance. In order to protect the plastic material
from scratches, a curable resin (such as a photo-curable resin) is
applied on a surface of a plastic substrate and cured to form a
hardcoat layer having a large hardness. The applications of the
hardcoat film having a hardcoat layer are now expanding. According
to the purposes, the hardcoat film may be required to have a
surface hardness or a heat resistance equivalent to a glass.
[0004] Japanese Patent Application Laid-Open Publication No.
2005-262597 (JP-2005-262597A, Patent Document 1) discloses a
hardcoat film that is excellent in abrasion resistance and sliding
property and is used for a pen input side of a pen input
transparent touch panel. The hardcoat film has a substrate film and
a coat layer on at least one side of the substrate film; the coat
layer consists of a resin composition containing 0.1 to 10 parts by
weight of an ultraviolet-curable silicone resin having a molecular
weight of 500 to 20000 relative to 100 parts by weight of an
ultraviolet-curable acrylate resin. In this document, as the
ultraviolet-curable silicone resin, a radical-polymerization type
resin and a cationic polymerization type resin are described; as
the cationic polymerization type resin, a polydimethylsiloxane
having an epoxypropoxypropyl end and an
(epoxycyclohexylethyl)methylsiloxane-dimethylsiloxane copolymer are
exemplified. This document also discloses that the
ultraviolet-curable silicone resin preferably has a molecular
weight of 500 to 20000 in order to express a pen-sliding property.
In Examples of this document, the hardcoat layer formed has a
pencil hardness of 3H.
[0005] Japanese Patent Application Laid-Open Publication No.
2009-279840 (JP-2009-279840A, Patent Document 2) discloses a
laminate containing a first cured resin layer having a pencil
hardness of not higher than HB and a thickness of 10 to 200 .mu.m
and a second cured resin layer having a pencil hardness of not
lower than H and a thickness of 2 to 50 .mu.m, wherein the first
cured resin layer is obtained by curing a first radiation-curable
resin composition, and the second cured resin layer is obtained by
curing a second radiation-curable resin composition. This document
discloses a radical-polymerizable monomer and a
radical-polymerizable oligomer as a radiation-curable resin. In
Examples of this document, the second cured resin layer formed has
a pencil hardness of 4H.
[0006] Unfortunately, these cured resin layers have insufficient
abrasion resistance. Generally, a hardcoat layer obtained by
radical polymerization of a polyfunctional acrylic monomer has a
pencil hardness of about 3H, although a higher hardness is required
depending on applications. In order to increase the hardness of the
hardcoat layer, it is possible to make the crosslinking density
higher by increasing the number of functional groups in the curable
resin or to increase the thickness of the hardcoat layer.
Unfortunately, the resulting hardcoat layer curls or cracks due to
contraction generated by hardening. Moreover, although there is
also a method for increasing the hardness of the hardcoat layer by
addition of an inorganic fine particle, it is difficult to prepare
a layer having specific properties according to applications. For
example, it is difficult to select a material for a hardcoat layer
to be used in an optical application that requires a high
transparency. For optical and other applications, it is also known
that a fluorine-containing leveling agent is added in order to
improve the surface smoothness or the antifouling property.
Unfortunately, the addition of the fluorine-containing material
tends to decrease the abrasion resistance.
RELATED ART DOCUMENTS
Patent Documents
[0007] Patent Document 1: JP-2005-262597A (claim 1, paragraphs
[0016], [0023], and [0024], and Examples)
[0008] Patent Document 2: JP-2009-279840A (claim 1, paragraph
[0018], Examples)
SUMMARY OF INVENTION
Technical Problem
[0009] It is therefore an object of the present invention to
provide a curable composition (a hardcoat liquid or a hardcoat
agent) for obtaining a cured product having improved surface
hardness and abrasion resistance, and a shaped product obtainable
by curing the composition.
[0010] Another object of the present invention is to provide a
curable composition for obtaining a cured product having an
excellent surface smoothness, a high transparency, and an improved
external appearance, and a shaped product obtainable by curing the
composition.
[0011] It is still another object of the present invention to
provide a curable composition of which even a thick cured product
can be prevented from curling or cracking and can be produced
efficiently, and a shaped product obtainable by curing the
composition.
[0012] It is a further object of the present invention to provide a
curable composition for obtaining a cured product having improved
heat resistance, antifouling property, and sliding property, and a
shaped product obtainable by curing the composition.
Solution to Problem
[0013] The inventors of the present invention made intensive
studies to achieve the above objects and finally found that the
combination use of a specific cationic curable silicone resin and a
leveling agent improves surface hardness and abrasion resistance of
a cured product thereof. The present invention was accomplished
based on the above findings.
[0014] That is, an aspect of the present invention provides a
curable composition (or a coating composition) comprising a
cationic curable silicone resin and a leveling agent. The cationic
curable silicone resin comprises a silsesquioxane unit, has a
monomer unit having an epoxy group in a proportion of not less than
50% by mol in a total monomer unit, and has a number average
molecular weight of 1000 to 3000. The cationic curable silicone
resin may have a silsesquioxane unit represented by the formula
(1): R.sup.1SiO.sub.3/2 (wherein R.sup.1 represents a group
containing an epoxy group; a hydrogen atom; or a hydrocarbon group)
in a proportion of not less than 50% by mol in the total monomer
unit constituting the cationic curable silicone resin. The cationic
curable resin may further comprise a unit represented by the
formula (2): R.sup.1SiO(OR.sup.2) (wherein R.sup.1 represents a
group containing an epoxy group; a hydrogen atom; or a hydrocarbon
group; R.sup.2 represents a hydrogen atom or a C.sub.1-4alkyl
group), and may have a molar ratio of the silsesquioxane unit
relative to the unit represented by the formula (2) of not less
than 5. The silsesquioxane unit may comprise a unit represented by
the formula (3): R.sup.3SiO.sub.3/2 (wherein R.sup.3 represents a
group containing an alicyclic epoxy group) and a unit represented
by the formula (4): R.sup.4SiO.sub.3/2 (wherein R.sup.4 represents
an aryl group which may have a substituent). The cationic curable
silicone resin may have a molecular weight distribution Mw/Mn of
about 1 to 3. The leveling agent may comprise a silicone-series
leveling agent and/or a fluorine-containing leveling agent and have
at least one of a reactive group to an epoxy group, and a
hydrolytically condensable group. The leveling agent may have a
proportion of about 0.1 to 10 parts by weight relative to 100 parts
by weight of the cationic curable silicone resin. The leveling
agent may comprise a silicone-series leveling agent having a
hydroxyl group. The silicone-series leveling agent may have a
proportion of about 0.5 to 5 parts by weight relative to 100 parts
by weight of the cationic curable silicone resin.
[0015] Another aspect of the present invention provides a shaped
product comprising a hardcoat layer that is a cured product of the
curable composition. The shaped product may comprise the hardcoat
layer alone and have an average thickness of 10 to 200 .mu.m. The
shaped product may further comprise a transparent substrate layer,
and the transparent substrate layer may have a side provided with
the hardcoat layer. The sheet-like shaped product (or shaped
product sheet) may be produced by a roll-to-roll system. The shaped
product may comprise the hardcoat layer and a three-dimensional
base (or shaped article).
Advantageous Effects of Invention
[0016] According to the present invention, the combination use of a
specific cationic curable silicone resin and a leveling agent
improves surface hardness and abrasion resistance of a cured
product thereof. The resin composition imparts an excellent surface
smoothness, a high transparency, and an improved external
appearance to a cured product of the composition. Moreover, even if
the cured product is thick, the cured product, which has an
excellent flexibility, is preventable from curling or cracking and
producible by a roll-to-roll system; the production efficiency is
improvable. Further, the cured product allows improvement in heat
resistance, antifouling property, and sliding property. Thus, the
cured product has an excellent durability even in a case where the
cured product is used for an electric machine that generates heat.
In addition, in a case where the cured product is stained with
fingerprints or ink (pen mark), the stain is easily removed (wiped
off) from the cured product.
DESCRIPTION OF EMBODIMENTS
[0017] [Curable Composition]
[0018] The curable composition of the present invention contains a
cationic curable silicone resin and a leveling agent.
[0019] (Cationic Curable Silicone Resin)
[0020] The cationic curable silicone resin contains a
silsesquioxane unit (a trifunctional T unit generally represented
by RSiO.sub.3/2). More specifically, the cationic curable silicone
resin contains a silsesquioxane unit represented by the formula
(1): R.sup.1SiO.sub.3/2 (wherein R.sup.1 represents a group
containing an epoxy group; a hydrogen atom; or a hydrocarbon
group).
[0021] In the formula (1), the group containing an epoxy group,
represented by R.sup.1, may include a group containing a glycidyl
group, or a group containing an alicyclic epoxy group.
[0022] The group containing a glycidyl group may include, for
example, glycidyl group; and a glycidyloxyC.sub.1-10alkyl group,
such as glycidyloxymethyl, 2-glycidyloxyethyl, 3-glycidyloxypropyl,
or 4-glycidyloxybutyl (in particular, a glycidyloxyC.sub.1-4alkyl
group).
[0023] As the group containing an alicyclic epoxy group, there may
be mentioned an epoxyC.sub.5-12cycloalkyl-straight- or
branched-chain C.sub.1-10alkyl group, for example, an
epoxycyclopentylC.sub.1-10alkyl group, such as
2,3-epoxycyclopentylmethyl, 2-(2,3-epoxycyclopentyl)ethyl,
2-(3,4-epoxycyclopentyl)ethyl, or 3-(2,3-epoxycyclopentyl)propyl;
an epoxycyclohexylC.sub.1-10alkyl group, such as
3,4-epoxycyclohexylmethyl, 2-(3,4-epoxycyclohexyl)ethyl,
3-(3,4-epoxycyclohexyl)propyl, or 4-(3,4-epoxycyclohexyl)butyl; and
an epoxycyclooctylC.sub.1-10alkyl group, such as
4,5-epoxycyclooctylmethyl, 2-(4,5-epoxycyclooctyl)ethyl, or
3-(4,5-epoxycyclooctyl)propyl.
[0024] In the group containing an alicyclic epoxy group, the
C.sub.5-12 cycloalkane ring may have a C.sub.1-4alkyl group [such
as methyl or ethyl (in particular, methyl group)] as a substituent.
The group containing an alicyclic epoxy group having a substituent
may include, for example, a C.sub.1-4alkyl-epoxyC.sub.5-12
cycloalkyl-straight- or branched-chain C.sub.1-10alkyl group, such
as 4-methyl-3,4-epoxycyclohexylmethyl,
2-(3-methyl-3,4-epoxycyclohexyl)ethyl,
2-(4-methyl-3,4-epoxycyclohexyl)ethyl,
3-(4-methyl-3,4-epoxycyclohexyl) propyl, or
4-(4-methyl-3,4-epoxycyclohexyl)butyl.
[0025] These groups, each containing an epoxy group, may be used
alone or in combination. Among them, in light of the hardness of
the cured product, a preferred one includes a group containing an
alicyclic epoxy group, particularly an epoxycyclohexyl-straight- or
branched-chain C.sub.1-4alkyl group which may have a C.sub.1-4alkyl
group (in particular, an epoxycyclohexylC.sub.2-4alkyl group, such
as 3,4-epoxycyclohexylethyl).
[0026] In the formula (1), the hydrocarbon group represented by
R.sup.1 may include an alkyl group, an alkenyl group, a cycloalkyl
group, a cycloalkenyl group, an aryl group, an aralkyl group, and
others.
[0027] As the alkyl group, there may be mentioned, for example, a
straight- or branched-chain C.sub.1-10alkyl group, such as methyl,
ethyl, propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, or
isopentyl.
[0028] The alkenyl group may include, for example, a straight- or
branched-chain C.sub.2-10alkenyl group, such as vinyl, allyl, or
isopropenyl.
[0029] As the cycloalkyl group, there may be mentioned, for
example, a C.sub.4-12cycloalkyl group, such as cyclobutyl,
cyclopentyl, or cyclohexyl.
[0030] The cycloalkenyl group may include a C.sub.5-12cycloalkenyl
group, such as cyclopentenyl or cyclohexenyl, and others.
[0031] As the aryl group, there may be mentioned, for example, a
C.sub.6-20aryl group, such as phenyl or naphthyl.
[0032] The aralkyl group may include a
C.sub.6-20aryl-C.sub.1-4alkyl group, such as benzyl, phenethyl, or
phenylpropyl, and others.
[0033] Each one of these hydrocarbon groups may have a substituent.
The substituent may include, but should not be limited to, these
hydrocarbon groups, an ether group, an ester group, a carbonyl
group, a siloxane group, a halogen atom (such as a fluorine atom),
a (meth)acryl group, a mercapto group, an amino group, and a
hydroxyl group. Each one of the ether group, the ester group, the
carbonyl group, and the siloxane group may be a linkage group.
Among these substituents, a C.sub.1-4alkyl group (such as methyl)
and a C.sub.6-20 aryl group (such as phenyl) are practically
used.
[0034] These hydrocarbon groups may be used alone or in
combination. Among these hydrocarbon groups, a preferred one
includes an alkyl group, an alkenyl group, and an aryl group,
particularly a C.sub.6-20aryl group. The C.sub.6-20aryl group may
be a phenyl group which may have a substituent, such as
methylphenyl (tolyl) or dimethylphenyl (xylyl). As the
C.sub.6-20aryl group, phenyl group is practically used.
[0035] Moreover, in the formula (1), R.sup.1 may be a combination
of a plural kind of groups, for example, a combination of the group
having an epoxy group and the hydrocarbon group.
[0036] Generally, a silsesquioxane having a complete cage structure
(or a fully condensed silsesquioxane) is formed from only the
above-mentioned silsesquioxane unit, designated as T3 unit.
According to the present invention, it is preferred to use a
cationic curable silicone resin further containing a unit
represented by the formula (2): R.sup.1SiO(OR.sup.2) (wherein
R.sup.1 represents a group containing an epoxy group; a hydrogen
atom; or a hydrocarbon group; R.sup.2 represents a hydrogen atom or
a C.sub.1-4alkyl group). The unit (2) is designated as T2 unit.
According to the present invention, the combination of the T3 unit
and the T2 unit in a specific ratio can form a silsesquioxane
having an incomplete cage structure, and the resulting cured
product has an improved hardness probably due to the incomplete
cage structure.
[0037] In the formula (2), the group containing an epoxy group and
the hydrocarbon group, each represented by R.sup.1, may include the
same epoxy group and hydrocarbon group as those in the formula (1).
Preferred epoxy group and hydrocarbon group are also the same as
those of the formula (1).
[0038] The C.sub.1-4alkyl group represented by R.sup.2 may include,
for example, a C.sub.1-4alkyl group, such as methyl, ethyl, propyl,
or butyl. These alkyl groups may be used alone or in combination.
Among these alkyl groups, a C.sub.1-2alkyl group, such as methyl or
ethyl (in particular, methyl group), is preferred.
[0039] The molar quantity of the T3 silsesquioxane unit (1) may be
5 times or more (for example, 5 to 20 times) as large as that of
the T2 unit (2). For example, the molar quantity of the T3
silsesquioxane unit (1) is about 5 to 18 times, preferably about 6
to 16 times, and more preferably about 7 to 15 times (in
particular, about 8 to 14 times) as large as that of the T2 unit
(2). In a case where the molar ratio (the T3 unit/the T2 unit) is
too small, the cured product may have a low hardness.
[0040] According to the present invention, for example, the molar
ratio (the T3 unit/the T2 unit) can be determined by .sup.29Si-NMR
spectroscopy. Specifically, in .sup.29Si-NMR spectrum, the signal
(peak) of the silicon atom of the T3 unit and that of the T2 unit
are shown at different positions (chemical shifts), and the
integration (relative area) of the signal for each peak can give
the above-mentioned ratio, the T3 unit/the T2 unit. More
specifically, for example, in a case where the group R.sup.1 of the
formula (1) in the cationic curable silicone resin is
2-(3',4'-epoxycyclohexyl)ethyl group, the signal of the silicon
atom of the T3 unit is shown in -64 to -70' ppm and the signal of
the silicon atom of the T2 unit is shown in -54 to -60 ppm. Thus in
this case, the above-mentioned ratio (the T3 unit/the T2 unit) can
be given by calculating the ratio of the integration of the signal
in -64 to -70 ppm (the T3 unit) relative to the integration of the
signal in -54 to -60 ppm (the T2 unit).
[0041] For example, the .sup.29 Si-NMR spectrum can be measured by
the following apparatus and conditions.
[0042] Measuring apparatus: trade name "JNM-ECA500NMR"
(manufactured by JEOL Ltd.)
[0043] Solvent: deuterochloroform
[0044] Number of integrations: 1800
[0045] Measuring temperature: 25.degree. C.
[0046] According to the present invention, the silsesquioxane unit
contains the unit (1). The silsesquioxane unit may contain a unit
represented by the formula (3): R.sup.3 SiO.sub.3/2 (wherein
R.sup.3 represents a group containing an alicyclic epoxy group) and
a unit represented by the formula (4): R.sup.4 SiO.sub.3/2 (wherein
R.sup.4 represents an aryl group which may have a substituent) in
combination.
[0047] The cationic curable silicone resin may contain other
monomer units (constitutional units of polyorganosiloxane) in
addition to the T unit (i.e., the silsesquioxane unit (1) and the
unit (2)). Examples of other monomer units may include a
monofunctional M unit (a unit generally represented by R.sup.3
SiO.sub.1/2), a difunctional D unit (a unit generally represented
by R.sup.2SiO.sub.2/2), and a tetrafunctional Q unit (a unit
generally represented by SiO.sub.4/2). In each one of the M unit
and the D unit, the organic group represented by R may include the
same groups as those represented by R.sup.1 of the formulae (1) and
(2).
[0048] The cationic curable silicone resin contains the unit having
an epoxy group (epoxy-containing unit) of not less than 50% by mol
(e.g., about 50 to 100% by mol), preferably about 55 to 100% by mol
(e.g., about 65 to 99.9% by mol), and more preferably about 80 to
99% by mol (e.g., about 90 to 98% by mol) in the total monomer unit
[the total (100% by mol in total) of the M unit, the D unit, the T
unit, and the Q unit constituting a polyorganosiloxane structure].
In a case where the ratio of the unit having an epoxy group is
excessively small, the cured product has a low hardness.
[0049] The proportion of the T3 silsesquioxane unit (1) in the
total monomer unit may be not less than 50% by mol, for example,
about 60 to 99% by mol, preferably about 70 to 98% by mol, and more
preferably about 80 to 95% by mol (particularly about 85 to 92% by
mol). In a case where the proportion of the silsesquioxane unit is
too small, the cured product may have a low hardness probably
because it is difficult to form a silsesquioxane having an
incomplete cage structure with a moderate molecular weight.
[0050] The total proportion of the silsesquioxane unit (1) and the
unit (2) (the total proportion of the difunctional T3 and T2 units)
in the total monomer unit is, for example, about 60 to 100% by mol,
preferably about 70 to 100% by mol, and more preferably about 80 to
100% by mol (particularly about 90 to 100% by mol). In a case where
the proportion of these units is too small, the cured product may
have a low hardness probably because it is difficult to form a
silsesquioxane having an incomplete cage structure with a moderate
molecular weight.
[0051] The cationic curable silicone resin may have a cage
structure (in particular, an incomplete cage structure). Whether
the cationic curable silicone resin has a cage (in particular, an
incomplete cage) silsesquioxane structure or not can be determined
by FT-IR spectroscopy [reference: R. H. Raney, M. Itoh, A.
Sakakibara and T. Suzuki, Chem. Rev. 95, 1409 (1995)].
Specifically, a cationic curable silicone resin having no intrinsic
absorption peak at or near 1050 cm.sup.-1 or at or near 1150
cm.sup.-1 and having one intrinsic absorption peak at or near 1100
cm.sup.-1 is identifiable as a resin having a cage (in particular,
an incomplete cage) silsesquioxane structure; a cationic curable
silicone resin having an absorption peak at or near 1050 cm.sup.-1
and an absorption peak at or near 1150 cm.sup.-1 is identifiable as
a resin having a ladder i silsesquioxane structure. According to
the present invention, the FT-IR spectrum can be measured by the
following apparatus and conditions.
[0052] Measuring apparatus: trade name "FT-720" (manufactured by
Horiba, Ltd.)
[0053] Measuring method: transmission method
[0054] Resolution: 4 cm.sup.-1
[0055] Measuring wave number range: 400 to 4000 cm.sup.-1
[0056] Number of integrations: 16
[0057] For the molecular weight of the cationic curable silicone
resin, the resin has a number average molecular weight (Mn) of
about 1000 to 3000, preferably about 1000 to 2800, and more
preferably about 1100 to 2600 (particularly about 1500 to 2500) in
terms of standard polystyrene in a gel permeation chromatography. A
cured product obtainable from a cationic curable silicone resin
having an excessively small molecular weight has low abrasion
resistance and a low heat resistance. A cationic curable silicone
resin having an excessively large molecular weight has a low
compatibility with other components in the composition, and thus a
cured product obtainable from the resin has a low heat
resistance.
[0058] For the molecular weight distribution (Mw/Mn) of the
cationic curable silicone resin, for example, the resin has a
molecular weight distribution (molecular weight dispersity) of
about 1 to 3, preferably about 1.1 to 2, and more preferably about
1.2 to 1.9 (particularly about 1.3 to 1.8) in terms of standard
polystyrene in a gel permeation chromatography. Ina case where the
molecular weight distribution is too large, the cured product may
have a low hardness. In contrast, a cationic curable silicone resin
having an excessively small molecular weight distribution may be
hard to handle, because the resin has an increased viscosity or is
in the solid state.
[0059] According to the present invention, the number average
molecular weight and the molecular weight distribution of the
cationic curable silicone resin can be measured by the following
apparatus and conditions.
[0060] Measuring apparatus: trade name "LC-20AD" (manufactured by
Shimadzu Corporation)
[0061] Column: Shodex KF-801 (two columns), KF-802, and KF-803
(manufactured by Showa Denko K.K.)
[0062] Measuring temperature: 40.degree. C.
[0063] Eluent: THF, sample concentration of 0.1 to 0.2% by
weight
[0064] Flow volume: 1 mL/minute
[0065] Detector: UV-VIS detector (trade name "SPD-20A",
manufactured by Shimadzu Corporation)
[0066] Molecular weight: in terms of standard polystyrene
[0067] The 5% weight loss temperature (T.sub.d5) of the cationic
curable silicone resin under an atmosphere of air is not
particularly limited to a specific one, and may be not lower than
330.degree. C. (e.g., about 330 to 450.degree. C.). The 5% weight
loss temperature (T.sub.d5) is preferably not lower than
340.degree. C. (e.g., about 340 to 420.degree. C.) and more
preferably not lower than 350.degree. C. (e.g., about 350 to
400.degree. C.). In a case where the 5% weight loss temperature is
too low, the cured product may have a low heat resistance. In
particular, the 5% weight loss temperature can be adjusted to not
lower than 330.degree. C. by providing a cationic curable silicone
resin having a T3/T2 unit molar ratio of not less than 5, a number
average molecular weight of 1000 to 3000, a molecular weight
distribution of 1 to 3, and one intrinsic peak at or near 1100
cm.sup.-1 in FT-IR spectrum. The 5% weight loss temperature, at
which 5% of the initial weight is lost under a constant rate of
heating, is used as an index of the heat resistance. According to
the present invention, the 5% weight loss temperature can be
measured under an atmosphere of air at a heating rate of 5.degree.
C./minute by TGA (thermogravimetric analysis).
[0068] (Process for Producing Cationic Curable Silicone Resin)
[0069] The cationic curable silicone resin can be produced by a
commonly used process for producing a polyorganosiloxane. The
process is not particularly limited to a specific one. For example,
the cationic curable silicone resin may be produced by
hydrolytically condensing one or more monomers (hydrolyzable silane
compounds). As each one of the hydrolyzable silane compounds, there
may be used a compound corresponding to each one of the units
described above.
[0070] Specifically, a monomer represented by R.sup.1SiX.sub.3 may
be used as a monomer corresponding to the T unit represented by the
formula (1) or (2); a monomer represented by (R.sup.1).sub.3SiX may
be used as a monomer corresponding to the M unit; a monomer
represented by (R.sup.1).sub.2SiX.sub.2 may be used as a monomer
corresponding to the D unit; a monomer represented by SiX.sub.4 may
be used as a monomer corresponding to the Q unit. Among these
monomers, at least the monomer corresponding to the T unit is used.
According to an object structure, the monomer may be used in
combination with other monomers.
[0071] In the formulae of the monomers described above, R.sup.1 is
the same as R.sup.1 of the formula (1), and X represents a
hydrolytically condensable group. The hydrolytically condensable
group represented by X may include, for example, a halogen atom
(such as fluorine, chlorine, bromine, or iodine atom) and an alkoxy
group (e.g., a C.sub.1-4alkoxy group, such as methoxy or ethoxy).
Among them, a C.sub.1-2alkoxy group (in particular, methoxy group)
is practically used.
[0072] In a case where two or more monomers are used in
combination, these hydrolyzable silane compounds may be
hydrolytically condensed simultaneously or consecutively. For the
consecutive reaction, the order of reactions is not particularly
limited to a specific one.
[0073] The hydrolytic condensation of each one of the hydrolyzable
silane compounds may be carried out in the absence of a solvent.
The hydrolytic condensation is preferably carried out in the
presence of a solvent. The solvent may include, for example, an
aromatic hydrocarbon (such as benzene, toluene, xylene, or
ethylbenzene); an ether (such as diethyl ether, dimethoxyethane,
tetrahydrofuran, or dioxane); a ketone (such as acetone, methyl
ethyl ketone, or methyl isobutyl ketone); an ester (such as methyl
acetate, ethyl acetate, isopropyl acetate, or butyl acetate); an
amide (such as N, N-dimethylformamide or N, N-dimethylacetamide); a
nitrile (such as acetonitrile, propionitrile, or benzonitrile; and
an alcohol (such as methanol, ethanol, isopropyl alcohol, or
butanol). These solvents may be used alone or in combination. Among
these solvents, a ketone (such as acetone) and an ether (such as
dioxane) are preferred.
[0074] The amount of the solvent is not particularly limited to a
specific one. The amount of the solvent can be selected from the
range of about 0 to 2000 parts by weight (for example, about 100 to
1000 parts by weight) relative to 100 parts by weight of the total
monomer according to the reaction time or other factors.
[0075] The hydrolytic condensation of the hydrolyzable silane
compound may proceed in the presence of a catalyst and water. The
catalyst may be an acid catalyst or may be an alkaline catalyst.
The acid catalyst may include, for example, a mineral acid (such as
hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, or
boric acid); a phosphate ester; a carboxylic acid (such as formic
acid, acetic acid, or trifluoroacetic acid); a sulfonic acid (such
as methanesulfonic acid, trifluoromethanesulfonic acid, or
p-toluenesulfonic acid); a solid acid (such as active clay); and a
Lewis acid (such as iron chloride). The alkaline catalyst may
include, for example, an alkali metal hydroxide (such as sodium
hydroxide or potassium hydroxide); an alkaline earth metal
hydroxide (such as magnesium hydroxide or calcium hydroxide); an
alkali metal carbonate (such as sodium carbonate or potassium
carbonate); an alkaline earth metal carbonate (such as magnesium
carbonate); an alkali metal hydrogencarbonate (such as sodium
hydrogencarbonate or potassium hydrogencarbonate); a salt of an
organic acid with an alkali metal (such as sodium acetate or
potassium acetate); a salt of an organic acid with an alkaline
earth metal (such as magnesium acetate); an alkali metal alkoxide
(such as sodium methoxide or sodium ethoxide); an alkali metal
phenoxide (such as sodium phenoxide); an amine (such as
triethylamine, N-methylpiperidine,
1,8-diazabicyclo[5.4.0]undeca-7-ene, or
1,5-diazabicyclo[4.3.0]nona-5-ene); and a nitrogen-containing
aromatic heterocyclic compound (such as pyridine, 2,2'-bipyridyl,
or 1,10-phenanthroline). These catalysts may be used alone or in
combination. These catalysts may be used in a state dissolved or
dispersed in water or a solvent.
[0076] The amount to be used of the solvent is not particularly
limited to a specific one. The amount of the solvent may selected
from the range of about 0.002 to 0.2 mol (in particular, about
0.005 to 0.1 mol) relative to 1 mol of the total amount of the
hydrolyzable silane compound.
[0077] The amount to be used of water is not particularly limited
to a specific one. The amount of water may be selected from the
range of about 0.5 to 20 mol (for example, about 1 to 15 mol)
relative to 1 mol of the total amount of the hydrolyzable silane
compound. The method of adding water is not particularly limited to
a specific one. The total amount (the total amount to be used) of
water may be added at a time or stepwise. The stepwise addition may
be continuous or intermittent.
[0078] For the reaction conditions of the hydrolytic condensation,
it is preferred to select the reaction conditions by which a
cationic curable silicone resin having the above-mentioned
constitutional units is obtainable. The reaction temperature of the
hydrolytic condensation is not particularly limited to a specific
one and, for example, is about 40 to 100.degree. C. (in particular,
about 45 to 80.degree. C.). The control of the reaction temperature
within this range efficiently allows easy adjustment of the
constitutional unit of the resin to the above-mentioned range. The
reaction time is not particularly limited to a specific one and,
for example, is about 0.1 to 10 hours (in particular, about 1.5 to
8 hours). The reaction may be carried out under an atmospheric
pressure or may be carried out under an applied pressure or a
reduced pressure. The atmosphere of the reaction may include, but
should not be limited to, an active gas atmosphere containing
oxygen (such as air), preferably an inactive gas atmosphere (such
as nitrogen or argon).
[0079] The hydrolytic condensation of the hydrolyzable silane
compound provides a polyorganosiloxane (silicone resin) containing
a polyorganosilsesquioxane unit. After the completion of the
hydrolytic condensation, the catalyst is preferably neutralized in
order to inhibit the opening of the epoxy group of the resin.
Moreover, the resulting silicone resin may be separated and
purified by, for example, a separation means, such as water
washing, acid washing, alkali washing, filtration, concentration,
distillation, extraction, crystallization, recrystallization, or
column chromatography, or a combination thereof.
[0080] (Leveling Agent)
[0081] As the leveling agent, there may be used a commonly used
leveling agent (e.g., an ethylene oxide adduct of acetylene glycol)
as far as the leveling agent has a capability to reduce a surface
tension. In light of an excellent capability to reduce a surface
tension, the leveling agent may preferably include a
silicone-series leveling agent and a fluorine-containing leveling
agent. According to the present invention, the combination use of
the cationic curable silicone resin and the leveling agent allows
the improvement of the surface smoothness, the transparency or
luster (external appearance), the sliding property, and others. Not
only does the use of a specific leveling agent allow the
maintenance of the hardness or abrasion resistance, but the control
of the blending ratio also allows the improvement of the hardness
or abrasion resistance.
[0082] The silicone-series leveling agent includes a leveling agent
having a polyorganosiloxane skeleton. As the polyorganosiloxane
skeleton, there may be used a polyorganosiloxane having the M unit,
the D unit, the T unit, and/or the Q unit, as with the cationic
curable silicone resin. Generally, a polyorganosiloxane having the
D unit is used. The polyorganosiloxane may have an organic group
(R) selected from among the hydrocarbon groups exemplified as the
group R.sup.1 of the formula (1) of the cationic curable silicone
resin. The organic group R usually includes a C.sub.1-4alkyl group
and/or an aryl group, preferably methyl group and/or phenyl group
(in particular, methyl group). The repeating number of siloxane
units (the degree of polymerization) is, for example, about 2 to
3000, preferably about 3 to 2000, and preferably about 5 to
1000.
[0083] The fluorine-containing leveling agent includes a leveling
agent having a fluoroaliphatic hydrocarbon skeleton. As the
fluoroaliphatic hydrocarbon skeleton, for example, there may be
mentioned a fluoroC.sub.1-10alkane, such as fluoromethane,
fluoroethane, fluoropropane, fluoroisopropane, fluorobutane,
fluoroisobutane, fluoro-t-butane, fluoropentane, or
fluorohexane.
[0084] Each one of these fluoroaliphatic hydrocarbon skeletons has
one or more fluorine atoms substituted in place of one or more
hydrogen atoms on the parent skeleton. In order to improve the
abrasion resistance, the sliding property, and the antifouling
property, a perfluoroaliphatic hydrocarbon skeleton, in which all
hydrogen atoms on the parent skeleton are replaced with fluorine
atoms, is preferred.
[0085] The fluoroaliphatic hydrocarbon skeleton may have a
polyfluoroalkylene ether skeleton, which is a repeating unit
through an ether bond. The fluoroaliphatic hydrocarbon group as the
repeating unit may be at least one member selected from the group
consisting of fluoroC.sub.1-4alkylene groups, for example,
fluoromethylene, fluoroethylene, fluoropropylene, and
fluoroisopropylene. These fluoroaliphatic hydrocarbon groups may be
the same or different from each other. The repeating number of
fluoroalkylene ether units (the degree of polymerization) may be,
for example, about 10 to 3000, preferably about 30 to 1000, and
more preferably about 50 to 500.
[0086] Among these skeletons, the polyorganosiloxane skeleton is
preferred in light of the excellent affinity with the cationic
curable silicone resin.
[0087] In order to impart various functions to the cationic curable
silicone resin, the leveling agent having such a skeleton may have
a functional group (such as a hydrolytically condensable group, or
a reactive group to an epoxy group), a radical-polymerizable group,
a polyether group, a polyester group, and/or a polyurethane group.
The silicone-series leveling agent may have a fluoroaliphatic
hydrocarbon group, or the fluorine-containing leveling agent may
have a polyorganosiloxane group.
[0088] The hydrolysable group may include, for example,
hydroxysilyl group; a trihalosilyl group (such as trichlorosilyl);
a dihaloC.sub.1-4alkylsilyl group (such as dichloromethylsilyl); a
dihaloaryl group (such as dichlorophenylsilyl); a
halodiC.sub.1-4alkylsilyl group (e.g., a
chlorodiC.sub.1-4alkylsilyl, such as chlorodimethylsilyl); a
triC.sub.1-4alkoxysilyl group (such as trimethoxysilyl or
triethoxysilyl); a diC.sub.1-4alkoxyC.sub.1-4alkylsilyl group (such
as dimethoxymethylsilyl or diethoxymethylsilyl); a
diC.sub.1-4alkoxyarylsilyl group (such as dimethoxyphenylsilyl or
diethoxyphenylsilyl); a C.sub.1-4alkoxydiC.sub.1-4alkylsilyl group
(such as methoxydimethylsilyl or ethoxydimethylsilyl); a
C.sub.1-4alkoxydiarylsilyl group (such as methoxydiphenylsilyl or
ethoxydiphenylsilyl); and a C.sub.1-4alkoxyC.sub.1-4alkylarylsilyl
group (such as methoxymethylphenylsilyl or
ethoxymethylphenylsilyl). Among them, a preferred one includes a
triC.sub.1-4alkoxysilyl group, such as trimethoxysilyl group, in
light of the reactivity or others.
[0089] The reactive group to an epoxy group may include, for
example, a hydroxyl group, an amino group, a carboxyl group, an
acid anhydride group (such as maleic anhydride group), and an
isocyanate group. Among them, a group to be widely used includes a
hydroxyl group, an amino group, an acid anhydride group, and an
isocyanate group in light of the reactivity or others. In view of
easiness of handling or obtaining, a hydroxyl group is
preferred.
[0090] The radical-polymerizable group may include, for example, a
(meth)acryloyloxy group and a vinyl group. Among them, a
(meth)acryloyloxy group is practically used.
[0091] As the polyether group, for example, there may be mentioned
a polyoxyC.sub.2-4alkylene group, such as a polyoxyethylene group,
a polyoxypropylene group, a polyoxybutylene group, or a
polyoxyethylene-polyoxypropylene group. In the polyether group, the
repeating number of oxyalkylene groups (the mole number of
oxyalkylene groups added) is, for example, about 2 to 1000,
preferably about 3 to 100, and preferably about 5 to 50. Among
them, a preferred one includes a polyoxyC.sub.2-3alkylene group,
such as a polyoxyethylene or a polyoxypropylene (in particular, a
polyoxyethylene group).
[0092] The polyester group may include, for example, a polyester
group obtainable by a reaction of a dicarboxylic acid [e.g., an
aromatic carboxylic acid (such as terephthalic acid) or an
aliphatic carboxylic acid (such as adipic acid)] and a diol (e.g.,
an aliphatic diol, such as ethylene glycol) and a polyester group
obtainable by a ring opening polymerization of a circular ester
(e.g., a lactone, such as caprolactone).
[0093] The polyurethane group may include, for example, a commonly
used polyester-based polyurethane group and a polyether-based
polyurethane group.
[0094] Each one of these functional groups may be introduced into
the polyorganosiloxane skeleton or the fluoroaliphatic hydrocarbon
skeleton by a direct bonding or through a linkage group (for
example, an alkylene group, a cycloalkylene group, an ether group,
an ester group, an amide group, a urethane group, or a linkage
group having a plurality of the above-mentioned groups).
[0095] Among these functional groups, a preferred one includes a
hydrolytically condensable group and a reactive group to an epoxy
group in the respect that the functional group can be allowed to
react with the cationic curable silicone resin to improve the
hardness of the cured product. The reactive group to an epoxy group
(in particular, hydroxyl group) is particularly preferred.
[0096] The hydroxyl group may be a terminal hydroxyl group of a
(poly)oxyalkylene group [such as a (poly)oxyethylene group]. The
leveling agent having a hydroxyl group may include, for example, a
silicone-series leveling agent (e.g., a
polydimethylsiloxanepolyoxyethylene) having a
(poly)oxyC.sub.2-3alkylene group (such as a (poly)oxyethylene
group) on a side chain of a polyorganosiloxane skeleton (such as a
polydimethylsiloxane); and a fluorine-containing leveling agent
(e.g., a fluoroalkylpolyoxyethylene) having a fluoroaliphatic
hydrocarbon group on a side chain of a (poly)oxyC.sub.2-3alkylene
skeleton (such as a (poly)oxyethylene).
[0097] As the silicone-series leveling agent, there may be used a
commercially available silicone-series leveling agent. The
commercially available silicone-series leveling agent may include,
for example, a BYK series leveling agent manufactured by BYK Japan
KK (e.g., "BYK-300", "BYK-301/302", "BYK-306", "BYK-307",
"BYK-310", "BYK-315", "BYK-313", "BYK-320", "BYK-322", "BYK-323",
"BYK-325", "BYK-330", "BYK-331", "BYK-333", "BYK-337", "BYK-341",
"BYK-344", "BYK-345/346", "BYK-347", "BYK-348", "BYK-349",
"BYK-370", "BYK-375", "BYK-377", "BYK-378", "BYK-UV3500",
"BYK-UV3510", "BYK-UV3570", "BYK-3550", "BYK-SILCLEAN3700", and
"BYK-SILCLEAN3720"), an AC series leveling agent manufactured by
Algin Chemie (e.g., "AC FS180", "AC FS360", and "AC S20"), a
POLYFLOW series leveling agent manufactured by Kyoeisha Chemical
Co., Ltd. (e.g., "POLYFLOW KL-400X", "POLYFLOW KL-400HF", "POLYFLOW
KL-401", "POLYFLOW KL-402", "POLYFLOW KL-403", and
"POLYFLOWKL-404"), aKP series levelingagentmanufactured by
Shin-Etsu Chemical Co., Ltd. (e.g., "KP-323", "KP-326", "KP-341",
"KP-104", "KP-110", and"KP-112") and a leveling agent manufactured
by Dow Corning Toray Co., Ltd. (e.g., "LP-7001", "LP-7002",
"8032ADDITIVE", "57ADDITIVE", "L-7604", "FZ-2110", "FZ-2105",
"67ADDITIVE", "8618ADDITIVE", "3ADDITIVE", and "56ADDITIVE").
[0098] As the fluorine-containing leveling agent, there may be used
a commercially available fluorine-containing leveling agent. The
commercially available fluorine-containing leveling agent may
include, for example, an OPTOOL series leveling agent manufactured
by Daikin Industries, Ltd. ("DSX", "DAC-HP"), a SURFLON series
leveling agent manufactured by AGC Seimi Chemical Co., Ltd. (e.g.,
"S-242", "S-243", "S-420", "S-611", "S-651", and "S-386"), a BYK
series leveling agent manufactured by BYK Japan KK (e.g.,
"BYK-340"), an AC series leveling agent manufactured by Algin
Chemie (e.g., "AC 110a" and "AC 100a"), a MEGAFACE series leveling
agent manufactured by DIC Corporation (e.g., "MEGAFACE F-114",
"MEGAFACE F-410", "MEGAFACE F-444", "MEGAFACE EXP TP-2066",
"MEGAFACE F-430", "MEGAFACE F-472SF", "MEGAFACE F-477", "MEGAFACE
F-552", "MEGAFACE F-553", "MEGAFACE F-554", "MEGAFACE F-555",
"MEGAFACE R-94", "MEGAFACE RS-72-K", "MEGAFACE RS-75", "MEGAFACE
F-556", "MEGAFACE EXP TF-1367", "MEGAFACE EXP TF-1437", "MEGAFACE
F-558", and "MEGAFACE EXP TF-1537", a FC series leveling agent
manufactured by Sumitomo 3M Limited (e.g., "FC-4430" and
"FC-4432"), a FTERGENT series leveling agent manufactured by Neos
Company Limited (e.g., "FTERGENT 100", "FTERGENT 100C", "FTERGENT
110", "FTERGENT 150", "FTERGENT 150CH", "FTERGENT A-K", "FTERGENT
501", "FTERGENT 250", "FTERGENT 251", "FTERGENT 222F", "FTERGENT
208G", "FTERGENT 300", "FTERGENT 310", and "FTERGENT 400SW"), and a
PF series leveling agent manufactured by Kitamura Chemicals Co.,
Ltd. (e.g., "PF-136A", "PF-156A", "PF-151N", "PF-636", "PF-6320",
"PF-656", "PF-6520", "PF-651", "PF-652", and "PF-3320").
[0099] These leveling agents may be used alone or in combination.
For example, a plural kind of the silicone-series leveling agents
may be used in combination, a plural kind of the
fluorine-containing leveling agents may be used in combination, or
the silicone-series leveling agent and the fluorine-containing
leveling agent may be used in combination. Among these leveling
agents, a silicone-series leveling agent having a hydroxyl group is
preferred, since the leveling agent has an excellent affinity with
the cationic curable silicone resin, can be allowed to react with
an epoxy group, and can improve the hardness or external appearance
of the cured product.
[0100] The silicone-series leveling agent having a hydroxyl group
may include, for example, a polyether-modified polyorganosiloxane,
in which a main chain or side chain of a polyorganosiloxane
skeleton (such as a polydimethylsiloxane) has a polyether group; a
polyester-modified polyorganosiloxane, in which a main chain or
side chain of a polyorganosiloxane skeleton has a polyester group;
and a silicone-modified (meth)acrylic resin, in which a
(meth)acrylic resin is modified with a polyorganosiloxane. For each
one of these leveling agents, the polyorganosiloxane skeleton may
have a hydroxyl group, or the polyether group, the polyester group,
or the (meth)acryloyl group may have a hydroxyl group. As the
leveling agent, for example, there may be used "BYK-370",
"BYK-SILCLEAN3700", "BYK-SILCLEAN3720" manufactured by BYK Japan
KK.
[0101] The ratio of the leveling agent relative to 100 parts by
weight of the cationic curable silicone resin can be selected from
the range of about 0.01 to 20 parts by weight, and, for example, is
about 0.05 to 15 parts by weight, preferably about 0.1 to 10 parts
by weight, and more preferably about 0.2 to 5 parts by weight. The
leveling agent in an excessively small ratio may decrease the
surface smoothness of the cured product. The leveling agent in an
excessively large ratio may decrease the hardness of the cured
product.
[0102] In particular, the ratio of the silicone-series leveling
agent relative to 100 parts by weight of the cationic curable
silicone resin may be, for example, about 0.1 to 10 parts by
weight, preferably about 0.2 to 5 parts by weight (e.g., about 0.3
to 3 parts by weight), and more preferably about 0.5 to 2 parts by
weight (particularly about 0.8 to 1.5 parts by weight). The ratio
of the fluorine-containing leveling agent relative to 100 parts by
weight of the cationic curable silicone resin may be, for example,
about 0.05 to 5 parts by weight, preferably about 0.1 to 3 parts by
weight (e.g., about 0.15 to 2 parts by weight), and more preferably
about 0.2 to 1 part by weight (particularly about 0.3 to 0.8 parts
by weight). The ratio adjustment of the leveling agent within such
a range can improve not only the surface smoothness of the cured
product but also the hardness of the cured product; it has not been
expected before that the leveling agent improves the hardness of
the cured product.
[0103] (Cationic Polymerization Initiator)
[0104] The curable composition of the present invention preferably
further contains a cationic polymerization initiator (an acid
generator) in order to promote the polymerization and improve the
hardness of the cured product. As the cationic polymerization
initiator, there may be used a commonly used photoacid generator or
a commonly used thermal acid generator, according to the kind of
the polymerization.
[0105] The photoacid generator may include, for example, a
sulfonium salt (a salt of a sulfonium ion and an anion), an
iodonium salt (a salt of an iodonium ion and an anion), a selenium
salt (a salt of a selenium ion and an anion), an ammonium salt (a
salt of an ammonium ion and an anion), a phosphonium salt (a salt
of a phosphonium ion and an anion), and a salt of a transition
metal complex ion and an anion. These photoacid generators may be
used alone or in combination. Among these photoacid generators, an
acid generator having a high acidity, e.g., a sulfonium salt, is
preferred in light of the improvement of the reactivity and the
improvement of the hardness of the cured product.
[0106] The sulfonium salt may include, for example, a
triarylsulfonium salt [such as a triphenylsulfonium salt, a
tri-p-tolylsulfonium salt, a tri-o-tolylsulfonium salt, a
tris(4-methoxyphenyl)sulfonium salt, a 1-naphthyldiphenylsulfonium
salt, a 2-naphthyldiphenylsulfonium salt, a
tris(4-fluorophenyl)sulfonium salt, a tri-1-naphthylsulfonium salt,
a tri-2-naphthylsulfonium salt, a tris(4-hydroxyphenyl)sulfonium
salt, a diphenyl[4-(phenylthio)phenyl]sulfonium salt, or a
4-(p-tolylthio)phenyldi-(p-phenyl)sulfonium salt]; a
diarylsulfonium salt (such as a diphenylphenacylsulfonium salt, a
diphenyl-4-nitrophenacylsulfonium salt, a diphenylbenzylsulfonium
salt, or a diphenylmethylsulfonium salt); a monoarylsulfonium salt
(such as a phenylmethylbenzylsulfonium salt, a
4-hydroxyphenylmethylbenzylsulfonium salt, or a
4-methoxyphenylmethylbenzylsulfonium salt); and a trialkylsulfonium
salt (such as a dimethylphenacylsulfonium salt, a
phenacyltetrahydrothiophenium salt, or a
dimethylbenzylsulfoniumsalt). These sulfoniumsaltsmay be used alone
or in combination. Among these sulfonium salts, a triarylsulfonium
salt is preferred.
[0107] The anion (counter ion) for forming a salt with a cation may
include, for example, SbF.sup.6-, PF.sup.6-, BF.sup.4-, a
fluoroalkylfluorophosphate ion [such as
(CF.sub.3CF.sub.2).sub.3PF.sup.3- or
(CF.sub.3CF.sub.2CF.sub.2).sub.3PF.sup.3],
(C.sub.6F.sub.5).sub.4B.sup.-, (C.sub.6F.sub.5).sub.4Ga.sup.-, a
sulfonate anion (such as trifluoromethanesulfonate anion,
pentafluoroethanesulfonate anion, nonafluorobutanesulfonate anion,
methanesulfonate anion, benzenesulfonate anion, or
p-toluenesulfonate anion), (CF.sub.3SO.sub.2).sub.3C.sup.-,
(CF.sub.3SO.sub.2).sub.2N.sup.-, a perhalogenate ion, a
halosulfonate ion, a sulfate ion, a carbonate ion, an aluminate
ion, a hexafluorobismuthate ion, a carboxylate ion, an arylborate
ion, a thiocyanate ion, and a nitrate ion. Among these anions, a
fluoroalkylfluorophosphate ion is preferred in light of solubility
and others.
[0108] As the photoacid generator, a commercially available
photoacid generator may be used. The commercially available
photoacid generator may include, for example, a photoacid generator
manufactured by San-Apro Ltd., such as "HS-1", "HS-1A", "HS-1P",
"HS-1N", "HS-1TF", "HS-1NF", "HS-1MS", "HS-1CS", "HS-1PC", "LW-S1",
"LW-S1NF", "K1-S", "CPI-101A", "CPI-100P", or"CPI300PG".
[0109] The thermal acid generator may include, for example, an
arylsulfonium salt, an aryliodonium salt, an allene-ion complex, a
quaternary ammonium salt, an aluminum chelate, and a boron
trifluoride amine complex. These thermal acid generators may be
used alone or in combination. Among these thermal acid generators,
an acid generator having a high acidity, e.g., an arylsulfonium
salt, is preferred in light of the improvement of the reactivity
and the improvement of the hardness of the cured product. As the
anion, there may be mentioned anions as described in the photoacid
generator. The anion may be an antimony fluoride ion, such as
SbF.sup.6-.
[0110] As the thermal acid generator, a commercially available
thermal acid generator may be used. The commercially available
thermal acid generator may include, for example, a thermal acid
generator manufactured by Sanshin Chemical Industry Co., Ltd. (such
as "SAN-AID SI-60L", "SAN-AID SI-60S", "SAN-AID SI-80L", or
"SAN-AID SI-100L") and a thermal acid generator manufactured by
ADEKA Corporation (such as "SP-66" or "SP-77").
[0111] The ratio of the cationic polymerization initiator relative
to 100 parts by weight of the cationic curable silicone resin can
be selected from the range of about 0.01 to 10 parts by weight, and
is, for example, about 0.05 to 5 parts by weight, preferably about
0.1 to 3 parts by weight, and more preferably about 0.3 to 2 parts
by weight (particularly about 0.5 to 1.5 parts by weight). An
excessively small ratio of the cationic polymerization initiator
may decelerate the progress of the curing reaction, resulting in a
low hardness of the cured product. An excessively large ratio of
the cationic polymerization initiator may decrease the storage
stability of the composition or may cause the coloration of the
cured product.
[0112] (Other Additives)
[0113] The curable composition may contain another curable resin.
Another curable resin may include, for example, an epoxy resin, an
oxetane resin, and a vinyl ether resin. These curable resins may be
used alone or in combination. Among these curable resins, an epoxy
resin is preferred in view of reactivity, miscibility, and others.
As the epoxy resin, there may be mentioned, for example, a glycidyl
ether-based epoxy resin, a glycidyl ester-based epoxy resin, an
alicyclic epoxy resin, a glycidylamine-based epoxy resin, and a
long-chain aliphatic epoxy resin. Among these epoxy resins, an
alicyclic epoxy resin is particularly preferred in light of a low
viscosity and an excellent sliding property. The ratio of another
curable resin relative to 100 parts by weight of the cationic
curable silicone resin is about not more than 100 parts by weight,
for example, about not more than 50 parts by weight (e.g., about 1
to 50 parts by weight), preferably about not more than 30 parts by
weight (e.g., about 5 to 30 parts by weight).
[0114] The curable composition may contain a commonly used additive
as far as the additive does not have a bad influence on abrasion
resistance or transparency. The commonly used additive may include,
for example, a curing agent (or a hardener) (e.g., an amine-series
curing agent, a polyaminoamide-series curing agent, an acid
anhydride-series curing agent, and a phenol-series curing agent), a
curing accelerator (e.g., an imidazole compound, an alkali metal or
alkaline earth metal alkoxide, a phosphine compound, an amide
compound, a Lewis acid complex compound, a sulfur compound, a boron
compound, and a condensable organic metal compound), a filler
(e.g., an inorganic filler, such as titanium oxide or alumina), a
stabilizer (e.g., an antioxidant, an ultraviolet absorber, a light
stabilizer, and a heat stabilizer), a plasticizer, a lubricant, an
antifoaming agent, an antistatic agent, and a flame retardant.
These additives may be used alone or in combination. The ratio of
the additive(s) relative to 100 parts by weight of the cationic
curable silicone resin is about not more than 100 parts by weight,
for example, about not more than 30 parts by weight (e.g., about
0.01 to 30 parts by weight) and preferably about not more than 10
parts by weight (e.g., about 0.1 to 10 parts by weight).
[0115] The curable composition may further contain an organic
solvent, for example, a ketone (such as acetone, methyl ethyl
ketone, methyl isobutyl ketone, or cyclohexanone), an ether (such
as dioxane or tetrahydrofuran), an aliphatic hydrocarbon (such as
hexane), an alicyclic hydrocarbon (such as cyclohexane), an
aromatic hydrocarbon (such as benzene), a halocarbon (such as
dichloromethane or dichloroethane), an ester (such as methyl
acetate or ethyl acetate), water, an alcohol (such as ethanol,
isopropanol, butanol, or cyclohexanol), a cellosolve (such as
methyl cellosolve or ethyl cellosolve), a cellosolve acetate, and
an amide (such as dimethylformamide or dimethylacetamide).
[0116] The curable composition may have a solid content weight of,
for example, about 1 to 80% by weight, preferably about 5 to 50% by
weight, and more preferably about 10 to 30% by weight.
[0117] [Shaped Product]
[0118] The shaped product of the present invention contains a
hardcoat layer containing (or formed from) the cured product of the
curable composition.
[0119] The shaped product of the present invention may contain the
hardcoat layer alone. For example, the shaped product may be a
thick sheet (a hardcoat sheet), which may be used as a substitute
for glass. The hardcoat sheet may be used as a light-guiding sheet
(a substitute for glass) useful for various optical applications
due to excellent transparency and heat resistance, and others.
Examples of the optical applications may include a television; a
personal computer; a display (such as a liquid crystal display or
an organic electroluminescent (EL) display) for a personal digital
assistance (e.g., a game machine, a tablet computer, a smart phone,
and a mobile phone); a solar cell; and a window of a vehicle (such
as an automobile) or a building. The shaped product sheet may have
an average thickness of, for example, not less than 10 .mu.m (e.g.,
about 10 to 1000 .mu.m), e.g., about 100 to 900 .mu.m, preferably
about 200 to 800 .mu.m, and more preferably about 300 to 700 .mu.m
(particularly about 400 to 600 .mu.m).
[0120] The shaped product of the present invention may comprise a
two-dimensional or three-dimensional base (or shaped article)
having the hardcoat layer directly or indirectly formed on a
surface thereof.
[0121] The two-dimensional base (or shaped article) may be in the
form of a film or a sheet. The film (or film-like base or substrate
film) may have the hardcoat layer on at least one side thereof. The
film may have the hardcoat layer on one side thereof or may have
the hardcoat layer on each side thereof. The two-dimensional base
may be formed from an organic material (such as a thermoplastic
resin or a thermosetting resin) or an inorganic material (such as a
metal, a glass, or a ceramics). As the base, a transparent
substrate film (a transparent substrate layer) is preferred, since
the hardcoat layer, which is a cured product of the curable
composition of the present invention, has an excellent
transparency.
[0122] The transparent substrate film is formed from a plastic. The
plastic may be a thermosetting resin. The transparent substrate
film for which the hardcoat layer is necessary is usually formed
from a thermoplastic resin in practical cases. The thermoplastic
resin may include, for example, an olefinic resin, a styrenic
resin, a polyester-series resin, a polyamide-series resin, a vinyl
chloride-series resin, a polycarbonate-series resin, a poly(vinyl
alcohol)-series resin, a polyimide-series resin, a
polysulfone-series resin, a poly(phenylene ether)-series resin, a
poly(phenylene sulfide)-series resin, a cellulose ester-series
resin, and a fluorine-containing resin. These plastics may be used
alone or in combination. Among these plastics, in light of
well-balanced properties, such as transparency and mechanical
properties, a preferred one includes a polyester-series resin
[e.g., a homo- or co-poly(alkylene arylate)-series resin containing
a C.sub.2-4alkyleneC.sub.6-12arylate unit, such as a poly(ethylene
terephthalate) (PET), a poly(butylene terephthalate) (PBT), or a
poly(ethylene naphthalate) (PEN)] and a polycarbonate-series resin
(e.g., a bisphenol A-based polycarbonate).
[0123] The transparent substrate film may be a single-layer film or
may be a laminate film. The laminate film may have a plurality of
the same type resin layers or may have a plurality of layers
different in type from each other.
[0124] The transparent substrate film may be a non-stretched film
or may be a stretched (monoaxially or biaxially stretched)
film.
[0125] The transparent substrate film may have an adhesive layer
(an adhesion layer), such as an anchor coat layer, on a surface
thereof in order to improve the adhesion to the hardcoat layer. The
transparent substrate film may be subjected to a surface treatment,
e.g., a discharge treatment (such as corona discharge or glow
discharge), an acid treatment, and a flame treatment. It is
preferred that the surface of the transparent substrate film have
an anchor coat layer formed from an adhesive or an agglutinant
(such as an acrylic resin, a urethane-series resin, or a
silicone-series resin) or be treated with a corona discharge. The
transparent substrate film may further contain an adhesion improver
in order to improve the adhesion.
[0126] The transparent substrate film may optionally contain an
additive as far as the additive does not decrease the transparency
of the transparent substrate film. The additive may include a
stabilizer (such as an antioxidant, an ultraviolet absorber, a
light stabilizer, or a heat stabilizer), a nucleation agent, a
flame retardant, a flame-retardant auxiliary, a filler, a
plasticizer, an impact modifier, a reinforcer, a coloring agent, a
dispersing agent, an antistatic agent, a foaming agent, an
antibacterial agent, and others. These additives may be used alone
or in combination.
[0127] It is sufficient that the two-dimensional shaped article has
a thickness of about not less than 1 .mu.m without particular
limitation. For example, the two-dimensional shaped article may
have a thickness of about 1 .mu.m to 100 mm, preferably about 20
.mu.m to 10 mm, and more preferably about 50 to 1000 .mu.m. The
thickness of the transparent substrate film is not particularly
limited to a specific one, and may be, for example, about 1 to 300
.mu.m, preferably about 20 to 250 .mu.m, and more preferably about
40 to 200 .mu.m (particularly about 50 to 150 .mu.m).
[0128] The hardcoat layer to be laminated on the two-dimensional
shaped article has a thickness of, for example, about 0.1 to 100
.mu.m (e.g., about 5 to 50 .mu.m), preferably about 1 to 30 .mu.m,
and more preferably about 3 to 20 .mu.m (particularly about 4 to 10
.mu.m). A laminated product of a soft two-dimensional shaped
article (such as a transparent substrate layer) and a hardcoat
layer having such a thickness has an excellent flexibility, and
thus the product can be produced by a roll-to-roll system. The
product is therefore producible with a high production
efficiency.
[0129] The shaped product having the hardcoat layer laminated on
the surface of the transparent substrate film, which also has an
excellent transparency, can be used for optional applications in
the same manner as in the above-mentioned product having the
hardcoat layer alone.
[0130] Each one of these shaped products (the sheet-like product
formed from the hardcoat layer alone, and the laminate of the
transparent substrate layer and the hardcoat layer) has an
excellent transparency.
[0131] The shaped product (the hardcoat layer alone, or the
laminate of the hardcoat layer and the transparent substrate layer)
has a low haze (e.g., at a thickness of 50 .mu.m) due to a high
surface smoothness. The shaped product has a haze, for example,
about 0.05 to 5%, preferably about 0.1 to 3% (e.g., about 0.15 to
2%), and more preferably about 0.2 to 1% (particularly about 0.3 to
0.8%) in accordance with Japanese Industrial Standards (JIS)
K7136.
[0132] The shaped product has a total light transmittance (at a
thickness of 50 .mu.m) of, for example, about 70 to 100%,
preferably about 80 to 100%, more preferably about 85 to 100%
(e.g., about 85 to 98%), and particularly about 90 to 100% (e.g.,
about 90 to 95%) in accordance with JIS K7361.
[0133] The three-dimensional base (or shaped article) is not
particularly limited to a specific one and may be a variety of
three-dimensional bases (or shaped articles), each formed from an
organic material or an inorganic material. The curable composition
of the present invention has an excellent coating property and can
form a uniform hardcoat layer on a complicated three-dimensional
base. In order to improve the adhesion to the hardcoat layer, the
surface of the three-dimensional base may also be subjected to a
surface treatment in the same manner as in the transparent
substrate film. The hardcoat layer has a thickness of, for example,
about 0.1 to 100 .mu.m (e.g., about 5 to 70 .mu.m), preferably
about 1 to 60 .mu.m (e.g., about 1 to 30 .mu.m), and more
preferably about 10 to 50 .mu.m (particularly about 30 to 40
.mu.m).
[0134] In the shaped product, the hardcoat layer (the cured product
of the curable composition) has a high surface hardness. The
hardcoat layer has a pencil hardness (under 750 g load) of not
lower than 3H (e.g., about 3H to 9H), preferably not lower than 4H
(e.g., about 4H to 9H), and more preferably not lower than 5H
(particularly about 5H to 9H) in accordance with JIS K5600. In
particular, the hardcoat layer can have a pencil hardness of not
lower than 7H (e.g., about 7H to 9H) and preferably not lower than
8H (e.g., about 8H to 9H) by regulating an aging step or others.
The hardcoat layer can obtain a pencil hardness of 9H, which is
equivalent to that of a glass. A hardcoat layer with an excessively
small pencil hardness has a low abrasion resistance.
[0135] The hardcoat layer also has a high abrasion resistance. Even
in a case where a #0000 steel wool with which a stick 1 cm in
diameter is covered is allowed to go back and forth on the surface
of the hardcoat layer 100 times under a load of 1.3 kg/cm.sup.2,
scratches do not result on the surface of the hardcoat layer.
[0136] The hardcoat layer has an excellent surface smoothness. The
hardcoat layer has an arithmetic average roughness Ra of about 0.1
to 20 nm, preferably about 0.1 to 10 nm, and more preferably about
0.1 to 5 nm in accordance with JIS B0601.
[0137] The hardcoat layer also has an excellent surface sliding
property. The hardcoat layer has a contact angle of water against a
surface thereof is not less than 60.degree., for example, about 60
to 110.degree., preferably about 70 to 110.degree., and more
preferably about 80 to 110.degree.. A hardcoat layer having an
excessively small contact angle of water against a surface thereof
may a low abrasion resistance probably due to a low sliding
property. The contact angle of water can be measured by an
automatic dynamic contact angle meter ("Type DCA-UZ" manufactured
by Kyowa Interface Science Co., Ltd.) or other means.
[0138] [Process for Producing Shaped Product]
[0139] The shaped product (coated shaped product or laminate) of
the present invention is produced through a step of applying the
curable composition on a support (a releasable support, or a
two-dimensional or three-dimensional base (or shaped article)) and
a step of curing the coated composition.
[0140] For the applying step, the method for applying the curable
composition may include a conventional manner, for example, a roll
coater, an air knife coater, a blade coater, a rod coater, a
reverse coater, a bar coater, a comma coater, a dip and squeeze
coater, a die coater, a gravure coater, a microgravure coater, a
silkscreen coater, a dipping method, a spraying method, and a
spinner method. Among these methods, a bar coater or a gravure
coater is used widely.
[0141] In a case where the curable composition contains an organic
solvent, or other cases, the curable composition may optionally be
dried after applying. The curable composition may be dried at a
temperature of about 40 to 150.degree. C., preferably about 50 to
120.degree. C., and more preferably about 60 to 100.degree. C.
(particularly about 60 to 80.degree. C.). The drying time is not
particularly limited to a specific one and can be selected from the
range of about 30 seconds to one hour. In order to prepare a
hardcoat layer having a pencil hardness equivalent to that of a
glass, the drying time may be adjusted. The drying time may be not
shorter than 3 minutes (e.g., about 3 minutes to one hour),
preferably not shorter than 5 minutes (e.g., about 5 to 30
minutes), and more preferably not shorter than 8 minutes (e.g.,
about 8 to 20 minutes).
[0142] In the curing step, the curable composition may be cured by
irradiation with active energy ray (or actinic ray) or by heating,
depending on the species of the cationic polymerization initiator.
Among them, the curable composition may usually be cured by
irradiation with an active energy ray.
[0143] As the active energy ray, heat and/or a light energy ray may
be used. In particular, the irradiation with the light energy ray
is usable. As the light energy ray, there may be used a radioactive
ray (such as gamma ray or X-ray), an ultraviolet ray, a visible
ray, an electron beam (EB), and others. The light energy ray is
usually an ultraviolet ray or an electron beam in practical cases.
In particular, in a case where a sheet having a high weather
resistance is produced, the electron beam irradiation may be used
because of polymerization without any polymerization initiator.
[0144] For the ultraviolet ray, the light source may include, for
example, a Deep UV lamp, a low-pressure mercury lamp, a
high-pressure mercury lamp, a superhigh-pressure mercury lamp, a
halogen lamp, and a laser light source (a light source, such as a
helium-cadmium laser or an excimer laser). The quantity of the
irradiation light (irradiation energy) varies depending on the
thickness of the coated layer. The quantity of the irradiation
light may for example be about 50 to 10000 mJ/cm.sup.2, preferably
about 70 to 5000 mJ/cm.sup.2, and more preferably about 100 to 1000
mJ/cm.sup.2. In order to improve the adhesion to the two- or
three-dimensional base, the quantity of light or the irradiation
time may be increased. The quantity of the irradiation light may
for example be about 300 to 10000 mJ/cm.sup.2 (particularly about
500 to 5000 mJ/cm.sup.2).
[0145] For the electron beam, an exposure source (e.g., an electron
beam irradiation apparatus) can be used for the electron beam
irradiation. The radiation dose (dose) varies depending on the
thickness of the coated layer. The radiation dose is, for example,
about 1 to 200 kGy (kilogray), preferably about 5 to 150 kGy, and
more preferably about 10 to 100 kGy (particularly about 20 to 80
kGy). The acceleration voltage is, for example, about 10 to 1000
kV, preferably about 50 to 500 kV, and more preferably about 100 to
300 kV.
[0146] The irradiation with the active energy ray (in particular,
the electron beam) may optionally be conducted in an atmosphere of
an inactive gas (for example, nitrogen gas, argon gas, and helium
gas).
[0147] As the succeeding step after the curing step by the active
energy ray, an aging step may be provided in which the cured
hardcoat layer is heat-treated (annealed). In the aging step, the
heating temperature is, for example, about 30 to 200.degree. C.,
preferably about 50 to 190.degree. C., and more preferably about 60
to 180.degree. C. The heating time is, for example, about 10
minutes to 10 hours, preferably about 30 minutes to 5 hours, and
more preferably 45 minutes to 3 hours. In particular, in a case
where a hardcoat layer having a pencil hardness equivalent to that
of a glass is prepared, it is preferred that the heating
temperature be a lower temperature, for example, about 30 to
150.degree. C., preferably about 50 to 120.degree. C., more
preferably about 60 to 100.degree. C. (particularly about 65 to
90.degree. C.) and the heating time be a longer time, for example,
about 0.5 to 5 hours, preferably about 1 to 3 hours, and more
preferably about 1.5 to 2.5 hours.
[0148] Meanwhile, in a case where the curable resin composition is
thermally cured using a thermal cationic polymerization initiator,
the heating temperature is, for example, about 30 to 200.degree.
C., preferably about 50 to 190.degree. C., and more preferably
about 60 to 180.degree. C.
[0149] As the curing step, a curing step by the active energy ray
(such as an ultraviolet ray) is preferred in view of applicability
to various supports.
[0150] In particular, since the curable composition of the present
invention and the cured product thereof each have an excellent
flexibility, the combination use of the curable composition or
cured product and a support having an excellent flexibility (such
as a soft transparent substrate layer) allows the production of the
shaped product by a roll-to-roll system. For example, the method of
the roll-to-roll system may continuously conduct the following
steps: a step of paying out a rolled support; a step of applying a
curable composition on at least one side of the paid-out support,
optionally removing a solvent by drying, and then curing the
curable composition; and winding the resulting hardcoat film onto a
roller.
[0151] The hardcoat sheet composed of the hardcoat layer alone can
be obtained through a step of releasing a releasable support from
the hardcoat layer.
EXAMPLES
[0152] 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. Raw materials used for
Examples and Comparative Examples are as follows. The hardcoat
layers obtained in Examples and Comparative Examples were evaluated
for the following items.
[0153] [Abbreviated Name of Raw Material]
[0154] (Curable Resin)
[0155] DPHA: dipentaerythritol hexaacrylate, "DPHA" manufactured by
Daicel-Allnex Ltd.
[0156] IRR214K: tricyclodecanedimethanol diacrylate, "IRR214K"
manufactured by Daicel-Allnex Ltd.
[0157] TA-100: acrylic silicone resin, "SQ TA-100" manufactured by
Toagosei Co., Ltd.
[0158] SI-20: acrylic silicone resin, "SQ SI-20" manufactured by
Toagosei Co., Ltd.
[0159] (Leveling Agent)
[0160] SILCLEAN3720: hydroxyl group-containing polyether-modified
polydimethylsiloxane, "BYK SILCLEAN3720" manufactured by BYK Japan
KK
[0161] SILCLEAN3700: hydroxyl group-containing silicone-modified
acrylic resin, "BYK SILCLEAN3700" manufactured by BYK Japan KK
[0162] BYK370: polyester-modified hydroxyl group-containing
polydimethylsiloxane, "BYK370" manufactured by BYK Japan KK
[0163] OPTOOL DSX: fluorine compound having hydrolytically
condensable group, "OPTOOL DSX" manufactured by Daikin Industries,
Ltd.
[0164] SURFLON S-242: ethylene oxide adduct of fluorine compound,
"SURFLON S-242" manufactured by AGC Seimi Chemical Co., Ltd.
[0165] SURFLON S-243: ethylene oxide adduct of fluorine compound,
"SURFLON S-243" manufactured by AGC Seimi Chemical Co., Ltd.
[0166] SURFLON S-386: polymer of fluorine compound, "SURFLON S-386"
manufactured by AGC Seimi Chemical Co., Ltd.
[0167] SURFLON S-651: polymer of fluorine compound, "SURFLON S-651"
manufactured by AGC Seimi Chemical Co., Ltd.
[0168] (Polymerization Initiator)
[0169] CPI300PG: photoacid generator, a solution of
triarylsulfonium fluoroalkylfluorophosphate in propylene glycol
methyl ether acetate, "CPI300PG" manufactured by San-Apro Ltd.
[0170] SAN-AID SI-60S: thermal acid generator, arylsulfonium salt,
"SAN-AID SI-60S" manufactured by Sanshin Chemical Industry Co.,
Ltd.
[0171] IRGACURE 184: photopolymerization initiator, "IRGACURE 184"
manufactured by BASF Japan Ltd.
[0172] (Substrate)
[0173] PET film: poly(ethylene terephthalate) film having a
hardcoat layer on a back side thereof, "0321E188 (WE98-)"
manufactured by Mitsubishi Plastics, Inc.
[0174] [Heat Resistance (5% Weight Loss Temperature
(T.sub.d5))]
[0175] A hardcoat film was obtained in the same manner as in
Examples except that a glass plate was used in place of a PET film.
From the hardcoat film, about 5 mg of a hardcoat layer was cut with
a cutter to give a sample. The sample was examined for the 5%
weight loss temperature using a differential thermogravimetric
analyzer ("TG/DTA6300" manufactured by Seiko Instruments Inc.)
under the following conditions.
[0176] Measuring temperature range: 25 to 550.degree. C.
[0177] Heating rate: 10.degree. C./minute
[0178] Gas atmosphere: nitrogen
[0179] [Haze and Total Light Transmittance]
[0180] The haze and the total light transmittance were measured
using a haze meter (trade name "NDH-5000W" manufactured by Nippon
Denshoku Industries Co., Ltd.).
[0181] [Pencil Hardness]
[0182] The pencil hardness of the surface of the hardcoat layer
obtained was measured under a load of 750 g in accordance with JIS
K5600-5-4.
[0183] [Abrasion Resistance]
[0184] Using a durability tester provided with a stick 1.0 cm in
diameter covered with a #0000 steel wool, the steel wool was
allowed to go back and forth on the surface of the hardcoat layer
100 times (at velocity: 10 cm/s) under a load of 1.3 kgf/cm.sup.2.
Then the hardcoat film was pasted on a black acrylic plate with an
optical agglutinant. The state of the surface was observed by a
fluorescent tube provided with a three-band fluorescent lamp, and
the number of scratches was counted.
[0185] [External Appearance]
[0186] The external appearance of the hardcoat film obtained was
visually observed and evaluated on the basis of the following
criteria.
[0187] A: The surface is smooth and highly lustrous.
[0188] B: The surface has a somewhat uneven thickness.
[0189] C: The surface has a significantly uneven thickness and is
poorly lustrous.
Reference Example 1
Preparation of Cationic Curable Silicone Resin
[0190] In a 300-mL flask (reactor) equipped with a thermometer, a
stirrer, a reflux condenser, and a nitrogen-introducing tube, 161.5
mmol (39.79 g) of 2-(3,4-epoxy)cyclohexylethyltrimethoxysialne, 9
mmol (1.69 g) of phenyltrimethoxysilane, and 165.9 g of acetone
were put under a nitrogen flow and heated to 50.degree. C. To the
resulting mixture, 4.70 g of a 5% by weight aqueous solution of
potassium carbonate (potassium carbonate: 1.7 mmol) was added
dropwise over 5 minutes, and then 1700 mmol (30.60 g) of water was
added dropwise thereto over 20 minutes. During the dropping, a
marked increase in temperature did not occur. Thereafter, the
polycondensation reaction was carried out for 4 hours under a
nitrogen flow at a temperature of 50.degree. C.
[0191] The analysis of the product in the reaction solution after
the polycondensation reaction showed that the product had a number
average molecular weight of 1911 and a degree of molecular weight
dispersion (molecular weight distribution Mw/Mn) of 1.47. The ratio
[the T3 unit/the T2 unit] of the T3 unit relative to the T2 unit in
the product obtained was calculated by .sup.29 Si-NMR spectrometry
and was determined to be 10.3.
[0192] Thereafter, the reaction solution was cooled, and washed
with water until the lower layer solution was neutralized. The
upper layer solution was separated and then distilled out the
solvent under the conditions of 1 mmHg and 40.degree. C. to give a
colorless and transparent liquid product (a cationic curable
silicone resin containing a silsesquioxane unit having an epoxy
group). The product (ESQ) had a T.sub.d5 of 370.degree. C.
[0193] (Production of Hardcoat Film)
[0194] A mixture of 100 parts by weight of the cationic curable
silicone resin (ESQ) obtained and 1 part by weight of a photoacid
generator (CPI300PG) was prepared and used as a hardcoat liquid
(curable composition).
[0195] The hardcoat liquid obtained was cast-coated on a PET film
with the use of a wire bar #30 and then allowed to stand for one
minute in an oven at 70.degree. C. (prebaking). Then, the coated
film was irradiated with an ultraviolet ray at a radiation dose of
400 mJ/cm.sup.2 for 5 seconds with a high-pressure mercury lamp
(manufactured by Eyegraphics Co., Ltd.). Finally, the coating of
the hardcoat liquid was cured by heat-treating (aging) the film at
150.degree. C. for one hour to give a hardcoat film having a
hardcoat layer. The hardcoat layer had a thickness of 38 .mu.m.
Reference Example 2
[0196] A hardcoat film was produced in the same manner as in
Reference Example 1 except that the cast-coated hardcoat liquid was
prebaked for 10 minutes in an oven at 70.degree. C. and
heat-treated (aged) at 80.degree. C. for 2 hours. The hardcoat
layer had a thickness of 36 .mu.m.
Examples 1 to 4
[0197] As shown in Table 1, a hardcoat film was produced in the
same manner as in Reference Example 2 except that a leveling agent,
as a raw material, was further added for the preparation of the
cationic curable silicone resin.
Examples 5 to 11
[0198] As shown in Table 1, a hardcoat film was produced in the
same manner as in Reference Example 1 except that a leveling agent,
as a raw material, was further added for the preparation of the
cationic curable silicone resin.
Example 12
[0199] A mixture of 100 parts by weight of the curable silicone
resin (ESQ) obtained in Reference Example 1, 0.3 parts by weight of
a thermal acid generator (SAN-AID SI-60S), and 0.5 parts by weight
of a leveling agent (SURFLON S-243) was prepared and used as a
hardcoat liquid.
[0200] The hardcoat liquid obtained was cast-coated on a PET film
with the use of a wire bar #30 and then allowed to stand for one
minute in an oven at 70.degree. C. (prebaking). Then, the coating
of the hardcoat liquid was cured by heat-treating the film at
150.degree. C. for one hour to give a hardcoat film having a
hardcoat layer. The hardcoat layer had a thickness of 36 .mu.m.
Comparative Examples 1 to 4
[0201] As shown in Table 1, a hardcoat film was produced in the
same manner as in Reference Example 1 except that a curable resin
and a polymerization initiator were mixed to prepare a hardcoat
liquid.
[0202] The evaluation of the hardcoat films obtained in Examples,
Reference Examples, and Comparative Examples are shown in Table
1.
TABLE-US-00001 TABLE 1 Reference Examples Examples 1 2 1 2 3 4 5 6
7 8 Composition Curable ESQ 100 100 100 100 100 100 100 100 100 100
(parts by weight) resin PETIA -- -- -- -- -- -- -- -- -- -- IRR214K
-- -- -- -- -- -- -- -- -- -- TA-100 -- -- -- -- -- -- -- -- -- --
SI-20 -- -- -- -- -- -- -- -- -- -- Leveling SILCLEAN3720 -- -- --
-- -- -- 1 -- -- -- agent SILCLEAN3700 -- -- 1 -- -- -- -- 1 -- --
BYK300 -- -- -- -- -- -- -- -- 1 -- OPTOOL DSX -- -- -- -- -- -- --
-- -- 0.5 SURFLON S-242 -- -- -- -- -- -- -- -- -- -- SURFLON S-243
-- -- -- 0.5 -- -- -- -- -- -- SURFLON S-386 -- -- -- -- 0.5 -- --
-- -- -- SURFLON S-651 -- -- -- -- -- 0.5 -- -- -- -- Initiator
CPI-300PG 1 1 1 1 1 1 1 1 1 1 SAN-AID SI-60S -- -- -- -- -- -- --
-- -- -- IRGACURE 184 -- -- -- -- -- -- -- -- -- -- Thickness
(.mu.m) 38 36 34 33 30 35 35 37 35 38 Haze (%) 0.5 0.5 0.5 0.4 0.2
0.2 0.5 0.6 0.4 0.3 Total light transmittance (%) 91.3 91 91 91
91.1 91.1 91.2 91.1 91.2 91 Pencil hardness 4H 9H 8H 8H 9H 8H 5H 5H
5H 5H Abrasion resistance about about 0 0 0 0 0 0 0 0 (Number of
scratches) 10 10 External appearance B B A A A A A A A A Examples
Comparative Examples 9 10 11 12 1 2 3 4 Composition Curable ESQ 100
100 100 100 -- -- -- -- (parts by weight) resin PETIA -- -- -- --
100 -- -- -- IRR214K -- -- -- -- -- 100 -- -- TA-100 -- -- -- -- --
-- 100 -- SI-20 -- -- -- -- -- -- -- 100 Leveling SILCLEAN3720 --
-- -- -- -- -- -- -- agent SILCLEAN3700 -- -- -- -- -- -- -- --
BYK300 -- -- -- -- -- -- -- -- OPTOOL DSX -- -- -- -- -- -- -- --
SURFLON S-242 0.5 -- -- -- -- -- -- -- SURFLON S-243 -- 0.5 -- 0.5
-- -- -- -- SURFLON S-386 -- -- 0.5 -- -- -- -- -- SURFLON S-651 --
-- -- -- -- -- -- -- Initiator CPI-300PG 1 1 1 -- -- -- 3 3 SAN-AID
SI-60S -- -- -- 0.3 -- -- -- -- IRGACURE 184 -- -- -- -- 5 5 -- --
Thickness (.mu.m) 36 34 35 36 35 32 40 37 Haze (%) 0.5 0.3 0.3 0.5
0.4 0.4 1.2 0.8 Total light transmittance (%) 91.1 91 91.2 90.8 90
90.2 90.5 91.5 Pencil hardness 5H 5H 5H 5H 3H H 2H 2H Abrasion
resistance 0 0 0 0 large large large large (Number of scratches)
number number number number External appearance A A A B C C C C
[0203] As apparent from the results shown in Table 1, the hardcoat
films obtained in Examples were excellent transparency, hardness,
abrasion resistance, and external appearance. In contrast, the
hardcoat films obtained in Comparative Examples had small hardness
and low abrasion resistance and external appearance.
INDUSTRIAL APPLICABILITY
[0204] The cured hardcoat layer of the curable composition of the
present invention is utilizable as a hardcoat layer for coating
various bases (or shaped articles) (two-dimensional or
three-dimensional bases (or shaped articles)) that require
properties including abrasion resistance, heat resistance, surface
smoothness, and antifouling property. The cured hardcoat layer,
which has an excellent optical properties including transparency,
is also utilizable for a display unit of various optical displays
[for example, electric or electronic equipment or precision
equipment (e.g., a personal computer, a television, a portable
telephone (e.g., a smart phone), a tablet computer, a game machine,
a mobile device, a clock or a watch, and an electronic
calculator)], an automobile windshield, and a window of a
building.
* * * * *