JP7028172B2 - Thermosetting composition - Google Patents

Description

The present invention relates to a thermosetting composition, and can be particularly preferably used for producing a resin sheet. The obtained resin sheet can be preferably used for an optical substrate such as a liquid crystal display (LCD) and an organic EL, and the touch panel is transparent and conductive. It can be preferably used by a resin sheet for forming a film, and belongs to these technical fields.
In the present specification, an acryloyl group or a methacryloyl group is referred to as a (meth) acryloyl group, and an acrylate or methacrylate is referred to as a (meth) acrylate.

In recent years, a touch panel integrated liquid crystal display device or a touch panel integrated organic EL display device has been widely applied to mobile devices such as smartphones, tablet terminals, and car navigation systems.
Conventionally, as a transparent conductive thin film of a touch panel, conductive glass in which a thin film of indium tin oxide (hereinafter referred to as "ITO") is formed on glass is well known, but it is possible because the base material is glass. Inferior in flexibility and workability. Therefore, depending on the application, a transparent conductive sheet based on a polyethylene terephthalate sheet is used because of its advantages such as excellent flexibility, workability, impact resistance, and light weight.

On the other hand, since it is expected to contribute to making the touch panel thinner and lighter, improving the transmittance, and reducing the cost of the member, a cover-integrated touch panel that directly forms a touch sensor such as ITO on the cover glass, so-called OGS (One Glass). Solution) is partially adopted. However, the OGS type has a problem that the touch panel cannot be operated if the cover glass is broken.

Therefore, as a cover material having excellent impact resistance, a so-called OPS (One Plastic Solution), in which a touch sensor such as ITO is directly formed on a resin sheet, has been proposed. However, the conventional acrylic resin-based or polycarbonate-based resin sheet has a low surface hardness and is easily damaged, and the toughness may be insufficient, so that the resin sheet may be cracked by an external impact force.

Patent Document 1 discloses a plastic member for forming a transparent conductive film obtained by photocuring a photocurable composition containing a bismethacrylate having an alicyclic skeleton and a mercapto compound.

In Patent Document 2, a photocurable composition containing a polyfunctional urethane (meth) acrylate having an alicyclic structure, a bifunctional (meth) acrylate having an alicyclic structure, and a photopolymerization initiator is photocured. A transparent resin molded body having a thickness of 50 to 500 μm is disclosed.

Japanese Unexamined Patent Publication No. 2002-161113 Japanese Unexamined Patent Publication No. 2007-56180

However, although the plastic member described in Patent Document 1 imparts appropriate toughness to the cured product by blending a mercapto compound, there is a problem that the pot life of the composition is shortened. There is also a problem that the surface hardness and scratch resistance are lowered.
Further, since it is not possible to exhibit the same rigidity as the transparent resin molded body and glass described in Patent Document 2, there is a problem that an appearance defect occurs in the heating step in the transparent conductive film or the metal electrode forming process.
As described above, a resin sheet having satisfactory physical properties as an OPS resin has not been found so far, and it is particularly difficult to achieve both hardness and toughness, and scratch resistance is also insufficient.

In the production of resin sheets, there are cases where the photocurable composition as described above is used and cases where the thermosetting composition is used, and each of them is used properly according to the purpose and characteristics.
The feature of the thermosetting composition is that it can be manufactured by a simple device and a plurality of sheets can be manufactured at the same time by one heating device. However, when a conventional thermosetting composition is used, it is heated. There is a problem that the resin sheet obtained by the above method is deformed or colored.
Further, even when the photocurable composition as described above is applied to the thermosetting composition, it has the same problem.

The present inventors have found that the obtained cured product is not easily cracked when used for producing a thermosetting composition, particularly a resin sheet, which has no problem of deformation or coloring and also has excellent mechanical properties such as hardness and bending characteristics. In order to find a thermosetting composition having excellent impact resistance and surface physical properties such as surface hardness and scratch resistance, a diligent study was conducted.

As a result of diligent studies to solve the above-mentioned problems, the present inventors have found that a composition containing a di (meth) acrylate having an isocyanurate ring and other polyfunctional (meth) acrylates can solve the above-mentioned problems. The headline has led to the completion of the present invention.

The present invention comprises the following component (A), component (B) and component (D), and optionally the component (C) below.
The total amount of the components (A) to (C) is 100% by weight, and the component (A) is contained in an amount of 20 to 60% by weight, the component (B) is contained in an amount of 80 to 40% by weight, and the component (C) is contained in an amount of 0 to 40% by weight. The present invention relates to a thermosetting composition containing 20 to 60 mol% of methacryloyl groups in 100 mol% of the total amount of ethylenically unsaturated groups contained in the components (A) to (C).
(A) Component: A compound having an isocyanurate ring and having two or more (meth) acryloyl groups (B) Component: A compound having two or more (meth) acryloyl groups and other than the component (A). A compound containing di (meth) acrylate (B-1) having a linear or branched alkylene group having 4 to 20 carbon atoms.
(C) Component: Compound having one ethylenically unsaturated group (D) Component: Thermal polymerization initiator Further, it may be paraphrased as follows.
The thermosetting composition of the present invention contains the above-mentioned component (A), (B) and (D), and may contain the above-mentioned component (C).
When the component (C) is contained, the component (A) is 20 to 60% by weight, the component (B) is 80 to 40% by weight, and (C) is contained in 100% by weight of the total amount of the components (A) to (C). ) Contains 40% by weight in excess of 0% by weight, and contains 20-60 mol% of methacryloyl groups in 100 mol% of the total amount of ethylenically unsaturated groups contained in the components (A) to (C). ,
When the component (C) is not contained, 20 to 60% by weight of the component (A) and 80 to 40% by weight of the component (B) are contained in 100% by weight of the total amount of the component (A) and the component (B). In addition, 20 to 60 mol% of methacryloyl groups are contained in 100 mol% of the total amount of ethylenically unsaturated groups contained in the component (A) and the component (B).

As the component (A), a compound having an isocyanurate ring and having two (meth) acryloyl groups and / or a compound having an isocyanurate ring and having three (meth) acryloyl groups is preferable.

The component (B) includes di (meth) acrylate (B-1) having a linear or branched alkylene group having 4 to 20 carbon atoms.
Further, as the component (B-1), 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate , 1,9-nonanediol di (meth) acrylate , and neopentyl One or more selected from glycol di (meth) acrylate is preferable.
Further, as the component (B), a compound further containing a compound having three or more (meth) acryloyl groups is preferable.

As the components (A) to (C), those containing no compound having a urethane bond are preferable.

As the ratio of the component (D), it is preferable to contain 0.1 to 5 parts by weight of the component (D) with respect to 100 parts by weight of the total amount of the components (A) to (C).

The cured product of the composition preferably has a flexural modulus of 2.5 GPa or more in the bending test, and preferably has a total light transmittance of 90% or more.

As the composition of the present invention, it is preferable to use it as a thermosetting composition for producing a resin sheet.
Further, the obtained resin sheet preferably has a cured product having a thickness of 100 μm to 5 mm.

As a method for producing a resin sheet, a method of pouring the thermosetting composition of the present invention into a molding mold composed of a base material, a base material for providing a weir, and a base material in this order and then heating the resin sheet is used. preferable.
Hereinafter, the present invention will be described in detail.

According to the composition of the present invention, the obtained cured product has no problems of deformation and coloring, has excellent mechanical properties such as hardness and bending characteristics, and is not easily cracked when used for producing a resin sheet. It has excellent impact resistance and surface physical properties such as surface hardness and scratch resistance.

FIG. 1 is a diagram showing an example of a molding mold used when producing a resin sheet using the composition of the present invention.

The present invention is a composition containing the components (A) to (D).
The total amount of the components (A) to (C) is 100% by weight, and the component (A) is contained in an amount of 20 to 60% by weight, the component (B) is contained in an amount of 80 to 40% by weight, and the component (C) is contained in an amount of 0 to 40% by weight. The present invention relates to a thermosetting composition containing 20 to 60 mol% of methacryloyl groups in 100 mol% of the total amount of ethylenically unsaturated groups contained in the components (A) to (C).
Hereinafter, the details of each component and composition will be described.

1. 1. Component (A ) Component (A) is a compound having an isocyanurate ring and having two or more (meth) acryloyl groups.
As the component (A), various compounds can be used as long as they have an isocyanurate ring and have two or more (meth) acryloyl groups.
As the component (A), a compound having an isocyanurate ring and having two (meth) acryloyl groups and / or a compound having three (meth) acryloyl groups is preferable.
Specific examples include di (meth) acrylate of isocyanuric acid alkylene oxide adduct, tri (meth) acrylate of isocyanuric acid alkylene oxide adduct, and di (meth) acrylate of ε-caprolactone adduct for isocyanuric acid alkylene oxide adduct. Examples thereof include tri (meth) acrylates of ε-caprolactone adducts with respect to isocyanuric acid alkylene oxide adducts.
Here, examples of the alkylene oxide in the alkylene oxide adduct include ethylene oxide and propylene oxide, and ethylene oxide is preferable. The number of moles of alkylene oxide added is preferably 1 to 3 mol in one molecule.
The number of moles of ε-caprolactone added is preferably 1 to 3 mol in one molecule.

As the component (A), only one kind of the above-mentioned compound may be used, or two or more kinds thereof may be used in combination.

The component (A) is commercially available, and examples thereof include the following products.
-Diacrylate of 3 mol of ethylene oxide isocyanuric acid adduct: Aronix M-215 manufactured by Toagosei Co., Ltd.
-Trichloroisocyanuric acid ethylene oxide 3 mol adduct triacrylate: A-9300 manufactured by Shin Nakamura Chemical Industry Co., Ltd., Funkrill FA-731A manufactured by Hitachi Chemical Co., Ltd.
・ Mixture of di and tri (meth) acrylate of 3 mol adduct of ethylene oxide isocyanuric acid: Aronix M-315 manufactured by Toagosei Co., Ltd.
-Triacrylate of 1 mol adduct of ε-caprolactone with respect to 3 mol adduct of ethylene oxide of isocyanuric acid: A-9300-1CL manufactured by Shin Nakamura Chemical Industry Co., Ltd. and the like can be mentioned.
-Triacrylate of ε-caprolactone 3 mol adduct with respect to isocyanuric acid ethylene oxide 3 mol adduct: Aronix M-327 manufactured by Toagosei Co., Ltd.

The content ratio of the component (A) is 20 to 60% by weight, preferably 30 to 55% by weight, based on 100% by weight of the total amount of the components (A) to (C).
When the content ratio of the component (A) is less than 20% by weight, the breaking strain and 50% impact breaking height are low, and the resin sheet becomes brittle. Scratch resistance is reduced.

2. 2. Component (B ) Component (B) is a compound having two or more (meth) acryloyl groups and is a compound other than the component (A).
As the component (B), a compound having two (meth) acryloyl groups [hereinafter, referred to as “bifunctional (meth) acrylate”] and a compound having three or more (meth) acryloyl groups [hereinafter, “3”. More than sensory (meth) acrylate "] and the like.

2-1.2 Functional (meth) acrylate Examples of the bifunctional (meth) acrylate include di (meth) acrylate having an alkylene group and polyalkylene glycol di (meth) acrylate.

A preferred example of the di (meth) acrylate having an alkylene group is a di (meth) acrylate having a linear or branched alkylene group having 4 to 20 carbon atoms [hereinafter referred to as “(B-1) component”]. preferable.
The component (B-1) is a di (meth) acrylate having a linear or branched alkylene group having 4 to 20 carbon atoms. In the present invention, the alkylene group means a divalent substituent obtained by removing two hydrogen atoms from an alkane.
These di (meth) acrylates are superior in hardness and scratch resistance of the cured product to di (meth) acrylates having a linear or branched alkylene group having 3 or less carbon atoms, and have a carbon number of 3 or less. The cured product has excellent rigidity and heat resistance with respect to 21 or more compounds.
The divalent linear alkylene group having 4 to 20 carbon atoms in the component (B-1) includes a 1,4-butylene group, a 1,6-hexylene group or a 1,9-nonylene having bonds at both ends. Groups are preferred.
Specific examples of the compound include 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, and 1,9-nonanediol di (meth) acrylate.

The divalent branched alkylene group having 4 to 20 carbon atoms in the component (B-1) includes a neopentylene group (2,2-dimethyl-1,3-propylene group) and 2-methyl having bonds at both ends. A -1,3-propylene group and an isobutylene group having a degree of polymerization of 5 or less are preferable.
Specific examples of the compound include neopentyl glycol di (meth) acrylate, which are most preferably used.

Among these compounds, the component (B-1) includes 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate and One or more selected from the group consisting of neopentyl glycol di (meth) acrylate is preferable.
As the component (B-1), one or more of these compounds are further selected from the group consisting of 1,6-hexanediol di (meth) acrylate and 1,9-nonanediol di (meth) acrylate. preferable.

As the polyalkylene glycol di (meth) acrylate, di (meth) acrylate having a total number of carbon atoms constituting the polyoxyalkylene group of 4 to 20 is preferable.
Specific examples of the polyalkylene glycol di (meth) acrylate include diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, and dipropylene glycol. Di (meth) acrylate, tripropylene glycol di (meth) acrylate, tetrapropylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, polybutylene glycol di (meth) acrylate and poly (1-methylbutylene glycol) di. Examples thereof include (meth) acrylate.

As the polyalkylene glycol di (meth) acrylate, one or more of these compounds selected from the group consisting of polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate and polybutylene glycol di (meth) acrylate are used. preferable.
Among these compounds, the polyalkylene glycol di (meth) acrylate is more preferably one or more selected from the group consisting of polyethylene glycol di (meth) acrylate and polypropylene glycol di (meth) acrylate.

Examples of the bifunctional (meth) acrylate other than the above include bifunctional (meth) acrylates having an aromatic skeleton such as di (meth) acrylate of bisphenol A alkylene oxide adduct and bisphenol A di (meth) acrylate;
Bifunctional (meth) acrylates with an aliphatic skeleton such as ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, and neopentyl glycol di (meth) acrylate;
Neopentyl glycol di (meth) acrylate hydroxypivalate;
Bifunctional (meth) acrylates with an alicyclic skeleton such as dimethyloltricyclodecanedi (meth) acrylate, cyclohexanedimethanol di (meth) acrylate and spiroglycol di (meth) acrylate;
In the above, examples of the alkylene oxide adduct include ethylene oxide adducts and propylene oxide adducts.

Examples of the bifunctional (meth) acrylate include polyester (meth) acrylate, epoxy (meth) acrylate, and polyether (meth) acrylate, in addition to the above-mentioned compounds.
Hereinafter, these compounds will be described.

2-1-1. Polyester (meth) acrylate Examples of the polyester (meth) acrylate include a dehydration condensate of a polyester diol and (meth) acrylic acid.
Here, examples of the polyester diol include a reaction product of the diol and a dicarboxylic acid or an anhydride thereof.
Examples of the diol include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, butylene glycol, polybutylene glycol, tetramethylene glycol, hexamethylene glycol, and neo. Examples thereof include low molecular weight diols such as pentylene glycol, cyclohexanedimethanol, 3-methyl-1,5-pentanediol and 1,6-hexanediol, and alkylene oxide adducts of these compounds.
Examples of the dicarboxylic acid or its anhydride include dicarboxylic acids such as orthophthalic acid, isophthalic acid, terephthalic acid, adipic acid, succinic acid, fumaric acid, maleic acid, hexahydrophthalic acid, tetrahydrophthalic acid and trimellitic acid, and compounds thereof. Anhydrous and the like.

2-1-2. Epoxy (meth) acrylate Epoxy (meth) acrylate is a compound obtained by addition-reacting (meth) acrylic acid to an epoxy resin. Examples of the epoxy resin include aromatic epoxy resins and aliphatic epoxy resins.

Specific examples of the aromatic epoxy resin include diglycidyl ethers having a benzene skeleton such as resorcinol diglycidyl ether and hydroquinone diglycidyl ether; bisphenol A, bisphenol F, bisphenol S, bisphenol fluorene or a diglycide adduct thereof. Examples thereof include bisphenol-type diglycidyl ether such as glycidyl ether; novolak-type epoxy resin such as phenol novolac-type epoxy resin and cresol novolak-type epoxy resin; glycidyl phthalimide; and o-phthalic acid diglycidyl ester.

Specific examples of the aliphatic epoxy resin include diglycidyl ethers of alkylene glycols such as ethylene glycol, propylene glycol, 1,4-butanediol and 1,6-hexanediol; diglycidyl ethers of polyethylene glycol and polypropylene glycol. Diglycidyl ether of polyalkylene glycol; diglycidyl ether of neopentyl glycol, dibromoneopentyl glycol and its alkylene oxide adduct; diglycidyl ether of hydrogenated bisphenol A and its alkylene oxide adduct; and tetrahydrophthalic acid diglycidyl ester. And so on.
In the above, as the alkylene oxide of the alkylene oxide adduct, ethylene oxide, propylene oxide and the like are preferable.

2-1-3. Polyether (meth) acrylate Polyether (meth) acrylate oligomers include polyalkylene glycol (meth) diacrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, and polytetramethylene glycol di (meth). ) Examples include acrylate.

2-3-functional or higher (meth) acrylate Trifunctional or higher (meth) acrylate includes trimethylolpropane tri (meth) acrylate, pentaerythritol tri or tetra (meth) acrylate, dimethylolpropane tri or tetra (meth) acrylate. , And polyol poly (meth) acrylates such as dipentaerythritol tri, tetra, penta or hexa (meth) acrylate; and trimethylolpropane alkylene oxide tri (meth) acrylate, pentaerythritol alkylene oxide adduct tri or tetra. Poly of polyol alkylene oxide adducts such as tri or tetra (meth) acrylates of (meth) acrylates, trimethylolpropane propanealkylene oxide adducts, and tri, tetra, penta or hexa (meth) acrylates of dipentaerythritol alkylene oxide adducts. Examples thereof include (meth) acrylate.
In the poly (meth) acrylate of the polyol alkylene oxide adduct, ethylene oxide and propylene oxide are preferable as the alkylene oxide.

2-3. As the preferred embodiment (B) component, only one kind of the above-mentioned compound may be used, or two or more kinds thereof may be used in combination.
The component (B) is preferably one containing the above-mentioned component (B-1), and the component (B-1) is 1,4-butanediol di (meth) acrylate or 1,6-hexanediol di. One or more selected from the group consisting of (meth) acrylate and 1,9-nonanediol di (meth) acrylate is preferable.
In this case, the content ratio of the component (B-1) is preferably 30 to 70% by weight in the total amount of the component (B) of 100% by weight.
Further, it is preferable that the component (B) contains a compound having three or more (meth) acryloyl groups.
In this case, as the content ratio of the compound having 3 or more (meth) acryloyl groups, 30 to 70 of the compounds having 3 or more (meth) acryloyl groups are contained in 100% by weight of the total amount of the component (B). % By weight is preferred.

2-4. Content ratio The content ratio of the component (B) is 40 to 80% by weight, preferably 45 to 75% by weight, based on 100% by weight of the total amount of the components (A) to (C). be.
If the content of the component (B) is less than 40% by weight, the surface hardness such as pencil hardness and scratch resistance are lowered, and if it exceeds 80% by weight, the breaking strain and the 50% impact breaking height are low. , The resin sheet becomes brittle.
Further, the preferable content ratio of the component (B-1) is 30 to 70% by weight in the total amount of the component (B) of 100% by weight.

3. 3. Component (C ) Component (C) is a compound having one ethylenically unsaturated group. The component (C) is a component to be blended for the purpose of adjusting the viscosity of the composition and adjusting various physical properties of the cured product according to the purpose.
Examples of the ethylenically unsaturated group in the component (C) include a (meth) acryloyl group, a vinyl group and a vinyl ether group, and a (meth) acryloyl group is preferable.

Examples of the component (C) include compounds having one (meth) acryloyl group [hereinafter referred to as “monofunctional (meth) acrylate”] and the like.
Specific examples of the monofunctional (meth) acrylate include isobornyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentanyl (meth) acrylate, cyclohexyl (meth) acrylate, trimethylcyclohexyl (meth) acrylate, 1-. Adamanthyl (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, t-butyl (meth) acrylate, hexyl ( Meta) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, glycidyl (meth) acrylate, dimethylaminoethyl (Meta) acrylate, diethylaminoethyl (meth) acrylate, benzyl (meth) acrylate, allyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, phenoxyethyl (meth) acrylate, о-phenylphenol ethylene oxide adduct (1) ~ 4 mol adduct) (meth) acrylate, p-cumylphenol ethylene oxide adduct (1-4 mol adduct) (meth) acrylate, phenyl (meth) acrylate, о-phenylphenyl (meth) acrylate, and p. -Cumylphenyl (meth) acrylate and the like can be mentioned.

The monofunctional (meth) acrylate may be a compound having various functional groups.
Examples of compounds having a carboxyl group are (meth) acrylic acid, polycaprolactone modified (meth) acrylic acid, Michael-added multimer of (meth) acrylic acid, 2-hydroxyethyl (meth) acrylate and phthal anhydride. Examples thereof include acid adducts and carboxyl group-containing (meth) acrylates such as 2-hydroxyethyl (meth) acrylate and anhydrous succinic acid adducts.

Examples of compounds having a hydroxyl group include (meth) acrylates having a hydroxyl group.
Examples of the (meth) acrylate having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, hydroxypentyl (meth) acrylate, hydroxyhexyl (meth) acrylate and hydroxy. Examples thereof include hydroxyalkyl (meth) acrylates such as octyl (meth) acrylates.

Examples of the compound having an amide group include N-vinylformamide, N-vinylacetamide, N-vinylpyrrolidone, and (meth) acrylamide-based compounds.
Specific examples of (meth) acrylamide compounds include N-alkyls such as N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N-isopropyl (meth) acrylamide and Nt-butyl (meth) acrylamide. Acrylamide;
N, N-dialkylacrylamides such as N, N-dimethyl (meth) acrylamide and N, N-diethyl (meth) acrylamide;
N-alkoxyalkyl (N-alkoxyalkyl) such as N-hydroxyethyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide and N-butoxymethyl (meth) acrylamide, N-methoxyethyl (meth) acrylamide. Examples include (meth) acrylamide; and (meth) acryloylmorpholin.

Examples of the compound having a carbamate group include (meth) acrylate having an oxazolidone group, and specific examples thereof include 2- (2-oxo-3-oxazolidinyl) ethyl acrylate.

Examples of the compound having an imide group include a compound having a maleimide group. Examples of the compound having a maleimide group include (meth) acrylate having a hexahydrophthalimide group and (meth) acrylate having a tetrahydrophthalimide group. Specific examples of the (meth) acrylate having a hexahydrophthalimide group include N- (meth) acryloyloxyethyl hexahydrophthalimide and the like. Examples of (meth) acrylates having a tetrahydrophthalimide group include N- (meth) acryloyloxyethyl tetrahydrophthalimide and the like.

Examples of the compound other than the monofunctional (meth) acrylate in the component (C) include aromatic vinyl compounds and the like.
Examples of the aromatic vinyl compound include styrene, alkyl styrene, halogenated styrene and the like.
Specific examples of alkyl styrene include methyl styrene, ethyl styrene, propyl styrene and the like.
Specific examples of the halogenated styrene include fluorostyrene, chlorostyrene, bromostyrene and the like.
As the aromatic vinyl compound, styrene is preferable among the above-mentioned compounds.

As the component (C), only one kind of the above-mentioned compound may be used, or two or more kinds thereof may be used in combination.

The content ratio of the component (C) is 0 to 40% by weight, preferably 0 to 20% by weight, based on 100% by weight of the total amount of the components (A) to (C).
If the content ratio of the component (C) exceeds 40% by weight, the unreacted component remains in the cured resin sheet, which plasticizes the resin sheet and lowers the flexural modulus.

4. Component (D ) Component (D) is a thermal polymerization initiator.
As the component (D), various compounds can be used, and organic peroxides and azo-based initiators are preferable. Further, among these, organic peroxide is more preferable because it has excellent polymerization initiator efficiency, can reduce outgas derived from the polymerization initiator decomposition product, and further makes the composition excellent in impact resistance.

Specific examples of the organic peroxide include 1,1-bis (t-butylperoxy) 2-methylcyclohexane and 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane, 1 , 1-bis (t-hexylperoxy) cyclohexane, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-butylperoxy) cyclohexane, 2, , 2-bis (4,4-di-butylperoxycyclohexyl) propane, 1,1-bis (t-butylperoxy) cyclododecane, dilauroyl peroxide, t-hexylperoxyisopropyl monocarbonate, t-butyl Peroxymaleic acid, t-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxylaurate, t-butylperoxypivalate, t-hexylperoxypivalate, 2,5- Dimethyl-2,5-di (m-tol oil peroxy) hexane, t-butyl peroxyisopropyl monocarbonate, t-butyl peroxy2-ethylhexyl monocarbonate, t-hexyl peroxybenzoate, 2,5-dimethyl- 2,5-Di (benzoylperoxy) hexane, t-butylperoxyacetate, 2,2-bis (t-butylperoxy) butane, t-butylperoxybenzoate, n-butyl-4,4-bis ( t-Butylperoxy) Valerate, Di-t-butylperoxyisophthalate, α, α'-bis (t-butylperoxy) diisopropylbenzene, dicumyl peroxide, 2,5-dimethyl-2,5-di (T-butylperoxy) hexane, t-butylcumyl peroxide, di-t-butyl peroxide, p-menthan hydroperoxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexine -3, diisopropylbenzene hydroperoxide, t-butyltrimethylsilyl peroxide, 1,1,3,3-tetramethylbutylhydroperoxide, cumenehydroperoxide, t-hexylhydroperoxide, and t-butylhydroperoxide. And so on.

Specific examples of the azo compound include 1,1'-azobis (cyclohexane-1-carbonitrile), 2- (carbamoylazo) isobutyronitrile, 2-phenylazo-4-methoxy-2,4-dimethylvaleronitrile. , Azodi-t-octane, azodi-t-butane and the like.
These may be used alone or in combination of two or more. Further, the organic peroxide can be subjected to a redox reaction by combining with a reducing agent.

The content ratio of the component (D) is preferably 0.1 to 5 parts by weight with respect to 100 parts by weight of the total amount of the components (A) to (C).
By setting the ratio of the component (D) to 0.1 parts by weight or more, the entire resin sheet can be uniformly cured, and by setting the ratio to 5 parts by weight or less, the residual low molecular weight polymerization initiator decomposition product is derived. It is possible to reduce the outgas.

5. Thermosetting composition The present invention comprises the component (A), the component (B) and the component (D), and optionally the component (C).
The total amount of the components (A) to (C) is 100% by weight, and the component (A) is contained in an amount of 20 to 60% by weight, the component (B) is contained in an amount of 80 to 40% by weight, and the component (C) is contained in an amount of 0 to 40% by weight. The present invention relates to a thermosetting composition containing 20 to 60 mol% of methacryloyl groups in 100 mol% of the total amount of ethylenically unsaturated groups contained in the components (A) to (C).

As the components (A) to (C), which are curable components that are cured by heating in the present invention, the above-mentioned compounds can be appropriately combined and used, but it is preferable that the compounds having a urethane bond are not contained. A composition containing a compound having a urethane bond, for example, urethane (meth) acrylate, causes the cured product to be colored.

The composition of the present invention needs to contain 20 to 60 mol% of methacryloyl groups in 100 mol% of the total amount of ethylenically unsaturated groups contained in the components (A) to (C), preferably 30. ~ 60 mol%.
If the proportion of the methacryloyl group is less than 20 mol%, the strain of the resin sheet after thermosetting becomes large, and if it exceeds 60 mol%, the coloring before and after the heat resistance test becomes large.
The ratio of methacryloyl groups in the present invention means the number of moles of all methacryloyl groups in the components (A) to (C) divided by the number of moles of total ethylenically unsaturated groups and multiplied by 100. In addition, since the compound having two or more (meth) acryloyl groups is often a mixture of compounds having different numbers of (meth) acryloyl groups in commercial products, the ratio of (meth) acryloyl groups is inaccurate. There may be. In this case, the (meth) acryloyl group equivalent of the raw material compound is measured in advance based on the iodine value or the like, and the calculation is performed based on this value.

As a method for producing the composition, a conventional method may be followed. For example, the component (A), the component (B) and the component (D), and, if necessary, the component (C) and other components are stirred and mixed. Can be manufactured.

The viscosity of the composition may be appropriately set according to the intended purpose, and is preferably 50 to 10,000 mPa · s.
In the present invention, the viscosity means a value measured at 25 ° C. using an E-type viscometer.

The composition of the present invention contains the above-mentioned (A) component, (B) component and (D) component as essential components, but various components such as (C) component may be blended depending on the purpose. Can be done.
Specific examples of the other components include an organic solvent, a plasticizer, a polymerization inhibitor and / or an antioxidant, a light resistance improver, and a compound having two or more mercapto groups [hereinafter, "polyfunctional mercaptan"]. ] Etc. can be mentioned.
Hereinafter, these components will be described. As the component described later, only one kind may be used, or two or more kinds may be used in combination.

5-1. Other ingredients
1) Organic solvent The composition of the present invention can be blended with an organic solvent for the purpose of improving the coatability on a substrate.
However, when the obtained resin sheet is used for a transparent conductive film, it is preferably one that does not contain an organic solvent.

Specific examples of the organic solvent include hydrocarbon solvents such as n-hexane, benzene, toluene, xylene, ethylbenzene and cyclohexane;
Methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutyl alcohol, 2-methoxyethanol, 2-ethoxyethanol, 2- (methoxymethoxy) ethanol, 2-isopropanolethanol, 2-butoxy Ethanol, 2-isopentyloxyethanol, 2-hexyloxyethanol, 2-phenoxyethanol, 2-benzyloxyethanol, furfuryl alcohol, tetrahydrofurfuryl alcohol, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, 1 -Alcohol-based solvents such as methoxy-2-propanol, 1-ethoxy-2-propanol and propylene glycol monomethyl ether;
Ethereal solvents such as tetrahydrofuran, dioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, bis (2-methoxyethyl) ether, bis (2-ethoxyethyl) ether and bis (2-butoxyethyl) ether;
Acetone, methyl ethyl ketone, methyl-n-propyl ketone, diethyl ketone, butyl methyl ketone, methyl isobutyl ketone, methylpentyl ketone, di-n-propyl ketone, diisobutyl ketone, holon, isophorone, cyclopentanone, cyclohexanone, methylcyclohexanone, etc. Ketone-based solvent;
Ester solvents such as ethyl acetate, butyl acetate, isobutyl acetate, methyl glycol acetate, propylene glycol monomethyl ether acetate, cellosolve acetate; and N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, N-methyl-2. -Aprotonic polar solvents such as pyrrolidone and γ-butyrolactone can be mentioned.

The ratio of the organic solvent may be appropriately set, but is preferably 90% by weight or less, more preferably 80% by weight or less in the composition.

2) Plasticizer A plasticizer can be added for the purpose of imparting flexibility to the cured product and improving brittleness.
Specific examples of the plasticizer include phthalic acid dialkyl esters such as dioctyl phthalate and diisononyl phthalate, adipic acid dialkyl esters such as dioctyl adipate, sevacinic acid esters, azelaic acid esters, phosphoric acid esters such as tricresyl phosphate, and polypropylene. Examples thereof include liquid polyether polyols such as glycol, polycaprolactone diols, and liquid polyester polyols such as 3-methylpentanediol adipate. Further, a soft acrylic polymer having a number average molecular weight of 10,000 or less can be mentioned.
The blending ratio of these plasticizers may be appropriately set, but is preferably 30 parts by weight or less with respect to a total of 100 parts by weight of the components (A) to (C) (hereinafter referred to as "curable components"). More preferably, it is 20 parts by weight or less.
By reducing the weight to 30 parts by weight or less, the strength and heat resistance can be improved.

3) Polymerization inhibitor and / and antioxidant The composition of the present invention may be added with a polymerization inhibitor and / and an antioxidant in order to improve storage stability.
As the polymerization inhibitor, hydroquinone, hydroquinone monomethyl ether, 2,6-di-tert-butyl-4-methylphenol, and various phenolic antioxidants are preferable, but sulfur-based secondary antioxidants and phosphorus-based secondary antioxidants are preferable. It is also possible to add a secondary antioxidant or the like.
The total compounding ratio of these polymerization inhibitors and / and antioxidants is preferably 3 parts by weight or less, more preferably 0.5 parts by weight or less, based on 100 parts by weight of the total amount of the curable components.

4) Light resistance improver A light resistance improver such as an ultraviolet absorber or a light stabilizer may be added to the composition of the present invention.
Examples of the ultraviolet absorber include 2- (2'-hydroxy-5-methylphenyl) benzotriazole, 2- (2'-hydroxy-3', 5'-di-t-butylphenyl) benzotriazole, and 2- ( Benzotriazole compounds such as 2'-hydroxy-3'-t-butyl-5'-methylphenyl) benzotriazole;
Triazine compounds such as 2,4-bis (2,4-dimethylphenyl) -6- (2-hydroxy-4-iso-octyloxyphenyl) -s-triazine;
2,4-Dihydroxy-benzophenone, 2-hydroxy-4-methoxy-benzophenone, 2-hydroxy-4-methoxy-4'-methylbenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2, 4, 4' -Trihydroxybenzophenone, 2,2', 4,4'-tetrahydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone, 2,3', 4,4'-tetrahydroxybenzophenone, or 2,2 (3) Benzophenone compounds such as -dihydroxy-4,4'-dimethoxybenzophenone can be mentioned.
Examples of the photostabilizer include N, N'-bis (2,2,6,6-tetramethyl-4-piperidyl) -N, N'-diformylhexamethylenediamine and bis (1,2,6,6). -) Pentamethyl-4-piperidyl) -2- (3,5-ditercious butyl-4-hydroxybenzyl) -2-n-butylmalonate, bis (1,2,2,6,6-pentamethyl-4-) Low molecular weight hindered amine compounds such as piperidinyl) sevacate; N, N'-bis (2,2,6,6-tetramethyl-4-piperidyl) -N, N'-diformylhexamethylenediamine, bis (1,2) , 2,6,6-Pentamethyl-4-piperidinyl) Hinderdamine-based photostabilizers such as high molecular weight hinderedamine compounds such as sevacate can be mentioned.
The blending ratio of the light resistance improver is preferably 0 to 5 parts by weight, more preferably 0 to 1 part by weight, based on 100 parts by weight of the total amount of the curable components.

5) Polyfunctional mercaptan The polyfunctional mercaptan can be blended as needed for the purpose of preventing curing shrinkage of the cured composition and for the purpose of imparting toughness.
As the polyfunctional mercaptan, various compounds can be used as long as they are compounds having two or more mercapto groups.
For example, pentaerythritol tetrakisthioglycolate, pentaerythritol tetrakisthiopropionate and the like can be mentioned.
The ratio of the polyfunctional mercaptan is preferably 20 parts by weight or less, more preferably 10 parts by weight or less, and particularly preferably 5 parts by weight or less with respect to 100 parts by weight of the curable component. By setting this ratio to 20 parts by weight or less, it is possible to prevent a decrease in heat resistance and rigidity of the obtained cured product.

6) Other components other than the above In addition to the above-mentioned other components, a mold release agent, a filler, a soluble polymer and the like can be added to the composition of the present invention.
The mold release agent is blended with the obtained resin sheet for the purpose of facilitating mold release from the base material. As the mold release agent, various surfactants can be used as long as the mold can be released from the base material and the compounding liquid and the cured product do not become turbid. For example, anionic surfactants such as alkylbenzene sulfonic acid, cationic surfactants such as alkylammonium salts, nonionic surfactants such as polyoxyethylene alkyl ethers, amphoteric surfactants such as alkylcarboxybetaine, and fluorine and silicon. Examples thereof include surfactants and the like.
The filler is blended for the purpose of improving the mechanical properties of the obtained resin sheet. As the filler, either an inorganic compound or an organic compound can be used. Examples of the inorganic compound include silica and alumina. A polymer can be used as the organic compound. As the filler, when the resin sheet obtained from the composition of the present invention is used for optical purposes, it is preferable that the filler does not deteriorate the optical physical characteristics.
The soluble polymer is blended for the purpose of improving the mechanical properties of the obtained resin sheet. The soluble polymer means a polymer that dissolves in the composition. In the present invention, polymers that are insoluble in the composition are referred to as fillers to distinguish them.
The blending ratio of these other compounds is preferably 20 parts by weight or less, more preferably 10 parts by weight or less, based on 100 parts by weight of the curable component.

5-2. Physical characteristics of the cured product The composition of the present invention has the effect of not causing deformation of the cured product after heat curing.
As a method for evaluating the physical properties, a method of evaluating by the average value of the in-plane phase difference is preferable.
The average value of the in-plane phase difference of the cured product of the present invention is preferably 10 nm or less, more preferably 8 or less.
In the present invention, the in-plane phase difference means the phase difference generated in the X direction and the Y direction due to the birefringence generated when the linearly polarized light is incident on the resin sheet.

As the physical properties of the cured product of the composition in the present invention, the flexural modulus in the bending test is preferably 2.5 GPa or more, more preferably 3.0 GPa or more. If the cured product of the composition has the elastic modulus, the rigidity is excellent.
The elastic modulus in the bending test in the present invention means a value calculated from stresses of 0.1% and 1% in a bending test conducted at a distance between fulcrums of 30 mm and a bending speed of 0.2 mm / min.

Further, when the cured product of the composition of the present invention is used for optical applications, the total light transmittance is preferably 90% or more, more preferably 91% or more.
In the present invention, the total light transmittance means the result of measuring a test piece having a thickness of 1 mm in accordance with JIS K7375.

Further, as the physical properties of the cured product of the composition in the present invention, those having a pencil hardness of 3H or more are preferable.
The pencil hardness in the present invention means a value measured by a method according to JIS K-5600.

5-3. Film thickness When the composition of the present invention is used for a resin sheet, the film thickness of the resin sheet may be appropriately set according to the purpose.
In particular, when it is used as a glass substitute application such as OPS, it is preferably 100 μm to 5 mm, more preferably 200 μm to 3 mm, and particularly preferably 300 μm to 2 mm.

6. Applications The composition of the present invention can be used for various purposes, and can be particularly preferably used as a molding material.
Examples of the molding material include a resin sheet and three-dimensional molding by an inkjet method, which can be preferably used for the resin sheet.
Hereinafter, the resin sheet will be described.

6-1. Method for Producing Resin Sheet As a method for producing a resin sheet using the composition of the present invention, various methods can be adopted, and examples thereof include the following four production methods.
1) Manufacturing method 1
A method of applying a composition to a substrate and heating it to cure the composition.
2) Manufacturing method 2
A method in which a composition is applied to a base material, bonded to another base material, and then heated to cure the composition.
3) Manufacturing method 3
A method in which a composition is poured into a substrate having a space and heated to cure the composition.
4) Manufacturing method 4
A method in which a composition is poured into a substrate having a space, bonded to another substrate, and then heated to cure the composition. When the resin sheet obtained from the composition of the present invention is used as a glass substitute. , The above-mentioned production method 4 is preferable.
As the polymerization method, either a batch method or a continuous method can be adopted.
Examples of the continuous type include a method of continuously supplying a belt-shaped base material by using the composition as a coating or pouring base material.

As another example of the continuous method, there is a method called a continuous cast method other than the above. That is, two continuous mirror-finished stainless steel belts are arranged one above the other in a caterpillar shape, the composition is poured between the belts, and the belts are slowly moved to continuously polymerize between the belts to form a resin. Examples include a method of manufacturing a sheet.
For glass replacement applications, the batch type is preferable.

6-1-1. Base material As the base material, either a peelable base material or a base material having no releasability (hereinafter referred to as “non-releaseable base material”) can be used.
Examples of the peelable base material include metal, glass, a release-treated film, and a surface-untreated film having a release property (hereinafter collectively referred to as "release material").
Examples of the mold release material include a silicone-treated polyethylene terephthalate film, a surface-untreated polyethylene terephthalate film, a surface-untreated cycloolefin polymer film, and a surface-untreated OPP film (polypropylene).

In order to obtain low haze and impart surface smoothness to the resin sheet obtained from the composition of the present invention, the surface roughness (center line average roughness) Ra as a peelable substrate is 0.15 μm or less. It is preferable to use a base material of 0.001 to 0.100 μm, and a base material of 0.001 to 0.100 μm is more preferable. Further, the haze is preferably 3.0% or less.
Specific examples of the base material include glass, surface-untreated polyethylene terephthalate film, surface-untreated OPP film (polypropylene), and the like.
In the present invention, the surface roughness Ra means that the unevenness of the surface of the film is measured and the average roughness is calculated.

Examples of the non-releaseable base material include various plastics other than the above, such as cellulose acetate resins such as polyvinyl alcohol, triacetyl cellulose and diacetyl cellulose, acrylic resins, polyesters, polycarbonates, polyarylates, polyether sulfone, norbornene and the like. Examples thereof include a cyclic polyolefin resin using the cyclic olefin as a monomer.

Examples of the base material having a space portion include a base material having a recess. Examples thereof include a mold release material in which a hole having a predetermined shape having a desired film thickness is formed and a recess is formed.
In this case, after the composition is poured into the base material having the recesses, another base material may be superposed on the base material having the recesses.
As another example of the base material having a space portion, there is also a case where a weir (spacer) is provided on the release material so that the cured product has a desired film thickness (hereinafter referred to as “molding mold”). .. In this case as well, another base material can be layered on the weir.
As the release material in this case, glass and glass that has undergone mold release treatment are preferable.

FIG. 1 will be described as an example of the molding die.
(A1-1) and (a1-2) in FIG. 1 are two base materials [Fig. 1: (1) in (a1-1) and (1)'in (a1-2)] and two sheets. Substrate with excellent releasability [Fig. 1: (2) of (a1-1) and (2)'of (a1-2)] and base material for providing one weir [Fig. 1: (a1-) This is an example of a molding mold composed of 1) (3)].
(A2) of FIG. 1 shows two base materials [Fig. 1: (1) and (1)'in Fig. 1: (a2)] and a base material for providing one weir [Fig. 1: (a2). (3)] is an example of a molding die.

As shown in FIG. 1, the base material for providing the weir [Fig. 1: (3) of (a1-1)] preferably has a shape having a hole for injecting the composition in the upper part [Fig. 1: (3-1) of (a1-1)]. As the base material for providing the weir, various materials can be used, and silicone rubber and the like can be mentioned.

As a specific example of (a1-1) and (a1-2) in FIG. 1, the base material is composed of two pieces of glass, two pieces of a mold-released film, and one piece of a base material for providing a weir. The molding die to be made is mentioned.
To superimpose a mold-released film [Fig. 1: (2) of Fig. 1: (a1-1)] on glass [Fig. 1: (1) of (a1-1)] and to provide a weir on it. The base material [(3) in Fig. 1: (a1-1)] is used as a stacking weir (spacer). Further, a mold-released film [Fig. 1: (a1-2) (2)'] is overlaid on it, and glass [Fig. 1: (a1-2) (1)'] is overlaid on it. Use a molding mold.

A specific example of (a2) in FIG. 1 is a case where a mold-released glass or metal is used as the base material [Fig. 1: (1) and (1)'] of (a2), and the cured product is used. Since the mold release property of the above is excellent, the two mold-released films in FIGS. 1 (a1-1) and (a1-2) are unnecessary.
Further, when the cured product itself of the composition is excellent in releasability, glass can be used as the base material [(1) and (1)'in FIG. 1: (a2)]. As an example in which the cured product itself of the composition is excellent in mold release property, there is an example in which a mold release agent is blended in the composition.

6-1-2. Pretreatment of composition When coating or injecting the composition of the present invention, the obtained resin sheet may be used to prevent foreign matter from entering or to prevent defects such as voids from being generated, or to have excellent optical properties. Therefore, it is preferable to use a purified product after stirring and mixing the raw material components.
As a method for purifying the composition, a method of filtering the composition is convenient and preferable. Examples of the filtration method include pressure filtration and the like.
The filtration accuracy is preferably 10 μm or less, more preferably 5 μm or less. The smaller the filtration accuracy, the more preferable. From the viewpoint of suppressing clogging of the filter, suppressing the frequency of filter replacement, and productivity, the lower limit is preferably 0.1 μm.

In the production of the resin sheet, in order to prevent bubbles from being contained in the cured product, it is preferable to perform defoaming treatment after blending each component.
Examples of the defoaming treatment method include standing, vacuum depressurization, centrifugation, cyclone (rotation / revolution mixer), gas-liquid separation membrane, ultrasonic waves, pressure vibration, and defoaming by a multi-screw extruder.

6-1-3. The coating method for coating the composition on the coating or injection substrate may be appropriately set according to the purpose, and is conventionally known as a bar coater, an applicator, a doctor blade, a knife coater, a comma coater, or a reverse roll. Examples thereof include a method of coating with a coater, a die coater, a lip coater, a gravure coater, a microgravure coater and the like.
When the composition is injected into a base material having a space portion, a method of injecting the composition into an injection device such as a syringe or an injection device can be mentioned.

The film thickness in this case may be appropriately set according to the target film thickness of the resin sheet described above.
In particular, when it is used as a glass substitute application, preferably an OPS application, it is preferably 100 μm to 5 mm, more preferably 200 μm to 3 mm, and particularly preferably 300 μm to 2 mm.

6-1-4. When a thermosetting composition is used as the heating composition, as a heating method, a method of immersing in a heat medium bath such as heat and oil, a method of using a hot press, a method of holding in a temperature control type constant temperature bath, and the like are used. Can be mentioned.
Conditions such as the heating temperature at the time of heating may be appropriately set according to the composition, the base material, the purpose and the like to be used. The heating temperature is preferably 40 to 250 ° C. The heating time may be appropriately set according to the composition to be used, the target resin sheet, and the like, and may be 3 hours or more. The upper limit of the heating time is preferably 24 hours or less in consideration of economic efficiency.
Further, the heating temperature can be changed according to the purpose. For example, there are cases where thermal polymerization initiators having different decomposition temperatures are used, and cases where the curing strain of the obtained resin sheet is eliminated.
Specific examples of the temperature include a method of polymerizing at a relatively low temperature of about 40 to 80 ° C. for several minutes to several hours and then polymerizing at a relatively high temperature of 100 ° C. or higher for several hours. According to the heating method, the curing strain of the obtained resin sheet can be eliminated, and a resin sheet having excellent various mechanical properties such as breaking strain can be obtained.

6-2. Use of Resin Sheet The resin sheet produced from the composition of the present invention can be particularly preferably used as an optical sheet.
The optical sheet formed from the composition of the present invention can be used for various optical applications. More specifically, a sheet used for a liquid crystal display device such as a polarizing element protective film for a polarizing plate, a support film for a prism sheet, a light guide film, and a liquid crystal display device integrated with a touch panel, and various functional films (for example, hard coat). Sheets, decorative sheets, transparent conductive sheets), base sheets for sheets with surface shapes (for example, moth-eye type antireflection sheets and sheets with textured structure for solar cells), light resistance (weather resistance) for outdoor use such as solar cells ) Sheets, films for LED lighting / organic EL lighting, transparent heat-resistant sheets for flexible electronics, and the like.

Since the optical sheet formed from the composition of the present invention has excellent heat resistance, it can be preferably used for producing a transparent conductive sheet. As the composition used for this purpose, a solvent-free composition containing no organic solvent is preferable because it can suppress the generation of outgas during vacuum formation of the transparent conductive body layer.
Further, since the optical sheet of the present invention has excellent heat resistance, flexibility and high strength even if it is a thick film, it can be used as a transparent conductive sheet base material for OPS. In this case, an optical sheet having a film thickness of 0.5 mm or more and 1.5 mm or less can be more preferably used.

The method for producing the transparent conductive sheet may be according to a conventional method.
Examples of the metal oxide forming the transparent conductor layer include indium oxide, tin oxide, zinc oxide, titanium oxide, indium-tin composite oxide, tin-antimon composite oxide, zinc-aluminum composite oxide, and indium-zinc composite. Examples thereof include oxides and titanium-niobium composite oxides. Of these, indium-tin composite oxides and indium-zinc composite oxides are preferable from the viewpoint of environmental stability and circuit processability.
As a method for forming the transparent conductor layer, a conventional method may be followed, and a method of forming the transparent conductor layer by a sputtering method using the optical sheet of the present invention and using the metal oxide and a vacuum film forming apparatus. And so on.
More specifically, the metal oxide is used as a target material, dehydrated and degassed, then evacuated to create a vacuum, the temperature of the optical sheet is set to a predetermined temperature, and then the optical sheet is placed on the optical sheet using a sputtering device. Examples thereof include a method of forming a transparent conductor layer.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.
Further, in the following, "part" means a part by weight, and "%" means% by weight.

1. 1. Examples 1 to 3 and Comparative Examples 1 to 3
1) Production of thermosetting composition The components (A), (B) and (D) shown in Tables 1 and 2 below are blended in the proportions shown in Tables 1 and 2 below, and after stirring and mixing, they are placed under vacuum. Defoamed at.
In the following, the ratio of methacrylic acid groups in the total amount of ethylenically unsaturated groups of 100 mol% is referred to as "methacrylic ratio".

The abbreviations in Tables 1 and 2 mean the following.
(A) Ingredient
M-315: Di and triacrylate of isocyanuric acid ethylene oxide adduct, Aronix M-315 manufactured by Toagosei Co., Ltd.
(B) Ingredient
NDDA: 1,9-nonandiacrylate, Viscoat # 260 manufactured by Osaka Organic Chemical Industry Co., Ltd.
NDDMA: 1,9-nonandimethacrylate, NOD-N manufactured by Shin Nakamura Chemical Industry Co., Ltd.
-TMP-MA: Trimethylolpropane Trimethacrylate, manufactured by Kyoeisha Chemical Co., Ltd., "Light Ester TMP"
M-309: Trimethylolpropane triacrylate, Aronix M-309 manufactured by Toagosei Co., Ltd.
(D) Ingredient
-BPO: t-Butylperoxy-2-ethylhexanoate, Perbutyl O manufactured by NOF CORPORATION

2) Production of resin sheet As the molding die for manufacturing the resin sheet, the molding die shown in FIG. 1 (a2) was used.
Two glass plates [80 mm × 80 mm, thickness 3 mm] and one silicone plate (thickness 1.0 mm) were used. As the glass plate, a glass plate that had been mold-released with a silicone-based compound was used.
A silicone plate [(a2): (3) in FIG. 1] was placed on a glass plate [(a2): (1) in FIG. 1] to form a weir (spacer). Further, a glass plate [(a2): (1)'in FIG. 1] was placed on it to form a laminating mold.

The composition obtained above was injected with a syringe from the pores of the molded silicone plate [(a 2): (3-1) in FIG. 1].
The mold was placed in a drying oven, heated at 60 ° C. for 0.5 hours, and then heated to 120 ° C. (heating ratio: 10 ° C./hour) over 6 hours to cure the composition.
After cooling to room temperature, the glass was removed from the molding die and demolded to obtain a resin sheet.

3) Evaluation method With respect to the obtained resin sheet, the average in-plane phase difference, yellow index, flexural modulus, total light transmittance, drop weight test and pencil hardness were evaluated according to the following method. The results are shown in Tables 1 and 2.

(1) Average of in-plane phase difference Using the obtained resin sheet, the in-plane phase difference is measured by a polarization measurement system (KAMAIRI manufactured by Photron), and the phase difference in the central part excluding 5 mm from the end is measured. It was measured and the average value was calculated.

(2) Yellow index: Y. I.
According to JIS K7375, the yellow index (YI) of the resin sheet before and after heating in air at 230 ° C. for 4 hours was measured with a thickness of 1 mm.

(3) Five test pieces having a length of 40 (mm) and a width of 10 (mm) were cut out from a resin sheet having a flexural modulus of 80 mm × 80 mm and a thickness of 1 mm, and Instron 5566A (distance between fulcrums 30 mm, 0.2 mm) was cut out. A 3-point bending test was performed at / sec, 25 ° C., 50% RH). The average value of 5 test pieces was defined as the flexural modulus (GPa).
In addition, when the fracture was performed with a strain of 1.2 times or more of the strain at which yield was observed and the maximum stress was observed, the fracture mode was ductile fracture, and when it was less than that, brittle fracture was performed.

(4) Total light transmittance The total light transmittance of a resin sheet having a thickness of 1 mm was measured according to JIS K7375.

(5) Drop weight test (50% impact fracture height)
A test piece having a length of 60 (mm) and a width of 60 (mm) was cut out from the obtained resin sheet, and the obtained resin sheet was placed on a metal ring having a diameter of 50 mm in accordance with JIS K7211-1. A conical weight having a tip diameter of 5 mm and a weight of 40 g was dropped from a predetermined height to the central portion of the resin molded body, and the height at which the probability of breakage was 50% or more was recorded. The number of tests at each height was 10.
(6) Pencil hardness
The hardness of the surface of the obtained resin sheet was measured according to JIS K-5600.

2. 2. Comparative Examples 4 to 9
1) Production of photocurable composition As a photopolymerization initiator for the components (A) and (B) shown in Tables 3 and 4 below, and other components, 2-hydroxy-2-methyl-1-phenyl-propane-1 -On [DaroCure 1173 manufactured by BASF Japan Ltd. Hereinafter, it is referred to as "DC1173". ] Was blended in the proportions shown in Tables 3 and 4 below, and after stirring and mixing, defoaming was performed under vacuum.

The abbreviations in Tables 3 and 4 mean the following, except for those defined above.
(B) Ingredient
-DCP-A: Dimethylol tricyclodecanediacrylate, manufactured by Kyoeisha Chemical Co., Ltd., light acrylate DCP-A
HBUA: Hexamethylene diisocyanate trimer and hydroxybutyl acrylate adduct

2) Production of resin sheet As the molding die for manufacturing the resin sheet, the molding die shown in FIG. 1 (a2) was used.
The composition obtained above was injected with a syringe from the pores of the molded silicone plate [(a 2): (3-1) in FIG. 1].
With respect to the obtained molding mold, an illuminance of 130 mW / cm ² (UV-A, Fusion UV Systems Japan) was used from one surface on the glass plate side using an ultraviolet irradiation device (high-pressure mercury lamp) manufactured by Eye Graphics Co., Ltd. UV POWER PUCK manufactured by Co., Ltd.) was exposed 20 times at a conveyor speed of 5 m / min. At this time, the irradiation surface was inverted for each exposure.
After allowing to cool, the glass was removed from the molding die, and the obtained cured product was heated at 150 ° C. for 16 hours to obtain a resin sheet.
3) Evaluation method
With respect to the obtained resin sheet, the average in-plane phase difference, yellow index, flexural modulus, total light transmittance, drop weight test and pencil hardness were evaluated according to the same method as described above. The results are shown in Tables 3 and 4.

3. 3. Comparative Examples 10 and 11
1) Evaluation of commercially available resin sheet Commercially available polymethylmethcrate [Acrylite L manufactured by Mitsubishi Rayon Co., Ltd. Hereinafter referred to as "PMMA"] and polycarbonate [Iupilon NF-2000 manufactured by Mitsubishi Gas Chemical Company, Inc.]. Hereinafter, using "PC"], the average in-plane phase difference, the yellow index, the flexural modulus, the total light transmittance, the drop weight test, and the pencil hardness were evaluated according to the same method as described above. The results are shown in Table 5.

4. Summary In the compositions of Examples 1 to 3, the obtained resin sheet is excellent in all of the average in-plane phase difference, the yellow index, the flexural modulus, the weight drop test, the total light transmittance and the hardness. rice field.
On the other hand, the thermosetting compositions containing the components (A), (B) and (D) do not contain methacrylate (methacryl ratio is less than 20 mol%), and Comparative Examples 1 to 3 have. In the composition, the average of the in-plane phase differences increases, that is, the resin sheet is deformed.
Further, the compositions of Comparative Examples 4 to 6 which are photocurable compositions containing the components (A) and (B) but do not contain methacrylate (methacrylic ratio is less than 20 mol%) are in-plane. The average of the phase difference increased, and the initial Y. I. The value of has risen. Although the methacryl ratio satisfies the range of the present invention, which contains the components (A) and (B), the composition of Comparative Example 7, which is a photocurable composition, has an initial in-plane phase difference due to a decrease in the average. And Y. after the heating test. I. The value of has risen.
Further, in the compositions of Comparative Examples 8 and 9 containing (A), first, a photocurable composition and further containing no methacrylate (methacrylic ratio is less than 20 mol%), the average in-plane phase difference is increased. In the initial stage and after the heating test, Y. I. The value of has risen. In particular, the composition of Comparative Example 9 containing urethane acrylate was found in Y. I. The value of was markedly increased.
Further, in Comparative Example 10 regarding the commercially available PMMA, the result of the drop weight test was deteriorated. Further, in Comparative Example 11 regarding a commercially available PC, the average of the in-plane phase differences is greatly increased.

The composition of the present invention can be used for various purposes, and can be particularly preferably used for producing a resin sheet.
The obtained resin sheet can be used for various purposes and can be preferably used as an optical sheet. The optical sheet can be preferably used for manufacturing a transparent conductive sheet, and can be preferably used for manufacturing a transparent conductive sheet for a touch panel.

Claims (12)

It contains the following (A) component, (B) component and (D) component, and optionally the following (C) component.
The total amount of the components (A) to (C) is 100% by weight, and the component (A) is contained in an amount of 20 to 60% by weight, the component (B) is contained in an amount of 80 to 40% by weight, and the component (C) is contained in an amount of 0 to 40% by weight. A thermosetting composition containing 20 to 60 mol% of methacryloyl groups in 100 mol% of the total amount of ethylenically unsaturated groups contained in the components (A) to (C).
(A) Component: A compound having an isocyanurate ring and having two or more (meth) acryloyl groups (B) Component: A compound having two or more (meth) acryloyl groups and other than the component (A). A compound containing di (meth) acrylate (B-1) having a linear or branched alkylene group having 4 to 20 carbon atoms.
Component (C): Compound having one ethylenically unsaturated group (D) Component: Thermal polymerization initiator According to claim 1, the component (A) is a compound having an isocyanurate ring and having two (meth) acryloyl groups and / or a compound having an isocyanurate ring and having three (meth) acryloyl groups. The thermosetting composition according to the above. The component (B-1) is 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate , 1,9-nonanediol di (meth) acrylate , and neopentyl glycol di. The heat-curable composition according to claim 1 or 2 , which is one or more selected from the group consisting of (meth) acrylate . The thermosetting composition according to any one of claims 1 to 3 , wherein the component (B) contains a compound having three or more (meth) acryloyl groups. The thermosetting composition according to any one of claims 1 to 4 , wherein the components (A) to (C) do not contain a compound having a urethane bond. The thermosetting composition according to any one of claims 1 to 5 , which contains 0.1 to 5 parts by weight of the component (D) with respect to 100 parts by weight of the total amount of the components (A) to (C). thing. The thermosetting composition according to any one of claims 1 to 6 , wherein the bending elastic modulus in the bending test of the cured product is 2.5 GPa or more. The thermosetting composition according to any one of claims 1 to 7 , wherein the cured product has a total light transmittance of 90% or more. A thermosetting composition for producing a resin sheet, which comprises the composition according to any one of claims 1 to 8 . A resin sheet made of a cured product of the composition according to claim 9 . The resin sheet according to claim 10, wherein the cured product has a thickness of 100 μm to 5 mm. A method for producing a resin sheet in which the composition according to claim 9 is poured into a molding die composed of a base material, a base material for providing a weir, and a base material, and then heated.

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