Polyorganosiloxane compounds, hard coat compositions, hard coat films and methods for producing the same, and displays

Abstract

Provided are: a silane compound represented by general formula (1); and a polyorganosiloxane compound obtained through condensation of said silane compound. This polyorganosiloxane compound includes a structure represented by general formula (11). In general formula (1) and general formula (11), Y is a divalent organic group having a main chain with 5 or more atoms.　This polyorganosiloxane compound can be used as a hard coating material. A hard coat layer (3) is formed by coating a hard coating composition containing the polyorganosiloxane compound on a transparent resin film (1) and then curing the same.

Description

Technical Field

[0001] Book The invention relates to a polyorganosiloxane compound which is a condensate of a silane compound, a hard coat composition containing the polyorganosiloxane compound as a curable resin component, a hard coat film and a method for producing the same. The invention also relates to a display provided with the hard coat layer.

Background Art

[0002] Curved displays and foldable displays (flexible displays, foldable displays) have been developed, and there has been a study to replace the glass material that has been used for display cover windows, substrates, etc. with a plastic film material having excellent flexibility. For cover windows of flexible displays including foldable displays, various properties such as transparency, hardness, and bend resistance are required.

[0003] Patent Documents 1 to 3 disclose polysiloxane-based hard coat materials containing a polyorganosiloxane compound having an alicyclic epoxy group as a curable resin component. A polyorganosiloxane compound having an alicyclic epoxy group is obtained by hydrolytic condensation of a silane compound (silane coupling agent) having an alicyclic epoxy group and an alkoxysilyl group.

[0004] Non-Patent Document 1 shows "2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane" as a commercially available product of a silane coupling agent having an alicyclic epoxy group. In Patent Documents 1 to 3, as a specific example of the hard coat material, a polyorganosiloxane compound obtained by hydrolytic condensation of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane as a curable resin component is disclosed.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] Japanese Patent Publication No. 2015-112599 [Patent Document 2] Japanese Patent Publication No. 2019-56106 [Patent Document 3] International Publication No. 2007 / 135909 [Non-patent literature]

[0006] [Non-Patent Document 1] Shin-Etsu Chemical Co., Ltd. Silane Coupling Agent Catalog, June 2021 Edition (http: / / www.silicone.jp / catalog / pdf / SilaneCouplingAgents_J.pdf) [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] Silane compounds containing alkoxysilyl groups are known to have poor storage stability, as hydrolysis and condensation of the alkoxysilyl groups gradually occur during storage, especially in humid and hot environments. Non-patent document 1 (page 12) states that dialkoxy-type silane compounds have better storage stability than trialkoxy-type compounds.

[0008] However, polyorganosiloxane compounds obtained by condensation of dialkoxy groups in silane compounds tend to have insufficient mechanical strength when used as hard coat materials because their siloxane bond network is two-dimensional and their crosslinking density is low.

[0009] The first aspect of the present invention is to provide a silane compound that has excellent storage stability and can form a film with excellent mechanical strength upon curing.

[0010] As shown in Patent Documents 1 to 3, hard coat materials using polyorganosiloxane compounds obtained by hydrolysis condensation of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane as the curable resin component exhibit high hardness. However, these hard coat materials have room for improvement in the flexural resistance of the cured products.

[0011] Foldable displays come in two types: those that fold with the display surface facing inward, and those that fold with the display surface facing outward. When a hard coat film is used as a cover window for a foldable display of the type that folds with the display surface facing outward, the hard coat film is bent so that the hard coat layer-forming surface faces outward when the device is folded. Hard coat films having a hard coat layer whose curable resin component is a polyorganosiloxane compound obtained by hydrolysis condensation of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane are prone to cracking in the hard coat layer when bent so that the hard coat layer faces outward.

[0012] A second aspect of the present invention aims to provide a hard coat material and a hard coat film that can achieve both excellent surface hardness and flexibility. [Means for solving the problem]

[0013] The silane compound of the present invention has a structure represented by general formula (1). [ka]

[0014] Hydrolysis condensation of this silane compound yields a polyorganosiloxane compound containing the structure represented by general formula (11).

[0015] [ka]

[0016] In general formula (1), R 1 R is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. 2 x is a hydrogen atom, or a monovalent hydrocarbon group selected from the group consisting of an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 25 carbon atoms, and an aralkyl group having 7 to 12 carbon atoms. x is 2 or 3, and x=3 is preferred. 1 The R groups are preferably methyl, ethyl, or propyl groups. 1 They may be the same or they may be different.

[0017] In general formulas (1) and (11), Y is a divalent organic group with 5 or more atoms in the main chain. Y may also contain an ester bond. The polyorganosiloxane compound preferably has a ratio of the structure represented by general formula (11) to the total amount of Si atoms of 0.3 or more.

[0018] In general formula (1), x=3 and silane compounds containing an ester bond in Y can be synthesized, for example, by method 1 or method 2 described below.

[0019] Method 1: A method for carrying out a transesterification reaction between an ester compound and an alcohol, and a hydrosilylation reaction between the terminal -CH=CH2 and the SiH of the trialkoxysilane, using an ester compound having an alicyclic epoxy group, an alcohol having -CH=CH2 at the terminal, and a trialkoxysilane as starting materials.

[0020] Method 2: A method for carrying out a transesterification reaction between an ester compound and an alcohol, and a hydrosilylation reaction between the terminal -CH=CH2 and the SiH of the trialkoxysilane, using an alcohol having an alicyclic epoxy group, an ester compound having -CH=CH2 at the terminal, and a trialkoxysilane as starting materials.

[0021] Polyorganosiloxane compounds obtained by hydrolysis condensation of silane compounds can be suitably used as hard coat materials. A hard coat composition according to one embodiment of the present invention contains the above-mentioned polyorganosiloxane compound and a photocationic polymerization initiator.

[0022] In one embodiment of the present invention, a hard coat film is formed by applying a hard coat composition containing a polyorganosiloxane compound onto a transparent resin film and curing it by irradiation with active energy rays to form a hard coat layer.

[0023] The hard coat film comprises a hard coat layer containing a cured polyorganosiloxane compound on at least one main surface of a transparent resin film. The hard coat film may also have a top coat layer on the hard coat layer. The top coat layer may contain a fluorine compound. For example, the top coat layer is formed by applying a composition containing a compound having an alkoxysilyl group and a perfluoroalkyl group in its molecule onto the hard coat layer and condensing the compound. [Effects of the Invention]

[0024] The silane compound of the present invention exhibits suppressed hydrolysis in the absence of a catalyst and possesses excellent storage stability. The hard coat film of the present invention achieves both excellent surface hardness and flexibility, and can be suitably used as a cover window material for foldable displays that are folded so that the display surface faces outward. [Brief explanation of the drawing]

[0025] [Figure 1] This is a cross-sectional view of a hard coat film according to one embodiment. [Figure 2] This is a cross-sectional view of a hard coat film according to one embodiment. [Modes for carrying out the invention]

[0026] [Silane compounds] One aspect of the present invention is a silane compound represented by the general formula (1).

Chemical formula

[0027] In the general formula (1), R 1 is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and R 2 is a monovalent hydrocarbon group selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 25 carbon atoms, and an aralkyl group having 7 to 12 carbon atoms, and x is 2 or 3. A plurality of R 1 may be the same or different. Y in the general formula (1) is a divalent organic group having 5 or more atoms in the main chain.

[0028] The silane compound represented by the general formula (1) (hereinafter sometimes referred to as "silane compound (1)") has two or three (-OR 1 ) in one molecule, and Si-OR 1 has hydrolyzability. After Si-OR 1 is hydrolyzed and condensed, a polyorganosiloxane compound is formed. From the viewpoint of hydrolyzability, R 1 is preferably an alkyl group having 3 or less carbon atoms (methyl group, ethyl group or propyl group), and particularly preferably a methyl group or an ethyl group. From the viewpoint of hydrolyzability, R 1 is most preferably a methyl group. On the other hand, a silane compound in which R 1 is an ethyl group has lower hydrolyzability of Si-OR 1 than a silane compound in which R 1 is a methyl group, and tends to have excellent stability of the compound during storage.

[0029] In the general formula (1), x is preferably 3. When x = 3 (that is, when three alkoxy groups (or hydroxy groups) -OR 1 are bonded to the Si atom), the above silane compound is represented by the following general formula (9) and does not have R 2 . R 1And Y are the same as in general formula (1).

[0030] [ka]

[0031] Silane compounds of general formula (9), i.e., silane compounds with x=3 in general formula (1), exhibit excellent adhesive strength and film strength because the polyorganosiloxane compounds obtained by hydrolysis and condensation of the silane compounds have a three-dimensional structure. On the other hand, trialkoxysilane-type silane compounds with x=3 are known to have lower storage stability compared to dialkoxysilane-type silane compounds with x=2, as hydrolysis and condensation of the alkoxysilyl group proceeds more easily under storage conditions, especially high temperature and high humidity. As described later, the storage stability of trialkoxysilane compounds is improved by the large chain length of the divalent organic group Y that connects the Si atom and the alicyclic epoxy group (3,4-epoxycyclohexyl group).

[0032] In general formula (1), Y is a divalent organic group with five or more atoms in the main chain. Y may be linear or branched. Y may be a linear or branched alkylene group and may contain atoms other than carbon in the main chain. For example, Y may be a heteroalkylene group and may contain ether bonds, ester bonds, amide bonds, carbonyl groups, imino groups, etc.

[0033] The number of atoms in the main chain refers to the number of atoms that make up the straight chain connecting the Si atom and the 3,4-epoxycyclohexyl group in general formula (1). In other words, a silane compound of general formula (1) is a compound in which the Si atom and the 3,4-epoxycyclohexyl group are bonded to each other via five or more atoms. For example, if Y is -CH2CH2CH2C(=O)O-, the number of atoms in the main chain of Y is 5, and hydrogen atoms and carbonyl oxygen atoms (=O) that do not make up the main chain are not counted in the number of atoms in the main chain.

[0034] Silane compound (1) is Si-OR in the absence of a catalyst. 1Hydrolysis is less likely to occur, resulting in excellent storage stability. In particular, trialkoxysilane-type compounds represented by general formula (9) are less likely to undergo hydrolysis even in high-temperature and high-humidity environments in the absence of a catalyst, and exhibit high reactivity in the presence of a catalyst.

[0035] The silane compound (1) exhibits superior storage stability as the number of atoms in the main chain of the divalent organic group Y increases. On the other hand, if the number of atoms in the main chain of organic group Y is excessively large, the reaction may be restricted even in the presence of a catalyst, resulting in poor practicality. Therefore, the number of atoms in the main chain of organic group Y is preferably 16 or less, more preferably 12 or less, even more preferably 10 or less, and may also be 8 or less.

[0036] Silane compound (1) exhibits excellent storage stability, with a large amount of unreacted alkoxysilyl groups (remaining alkoxysilyl groups) after exposure to an environment of 85°C and 85% relative humidity for 20 hours. The remaining alkoxysilyl group percentage after exposure to an environment of 85°C and 85% relative humidity for 20 hours is preferably 30% or more, more preferably 50% or more, even more preferably 60% or more, and may be 70% or more or 80% or more.

[0037] The silane compound (1) may have a remaining alkoxysilyl group of 30% or more after exposure to an environment of 85°C and 85% relative humidity for 96 hours. The remaining alkoxysilyl group of the silane compound after exposure to an environment of 85°C and 85% relative humidity for 96 hours may be 40% or more, 50% or more, or 60% or more.

[0038] Silane compound (1) has a bulky alicyclic epoxy group (3,4-epoxycyclohexyl group), and furthermore, it has a divalent organic group Y with a long chain length (more than 5 atoms in the main chain) that acts as a spacer between the Si atom and the 3,4-epoxycyclohexyl group, resulting in a large molecular volume. Therefore, the Si-OR of the water molecule 1 Access to the intermolecular Si-OR is restricted. 1 Because the frequency of contact between them is low, Si-OR occurs in the absence of a catalyst. 1 It is thought to have low reactivity and high stability.

[0039] When the divalent organic group Y is a linear alkylene group, specific examples include pentamethylene, hexamethylene, heptamethylene, octamethylene, decamethylene, dodecamethylene, tetradecamethylene, and hexadecamethylene. Y may also be a linear alkylene in which some or all of the hydrogen atoms of the methylene (-CH2-) group are substituted by substituents. Specific examples of substituents include methyl, ethyl, propyl, butyl, pentyl, hexyl, cyclohexyl, phenyl, amino, (meth)acrylic, halogen, allyl, vinyl, mercapto, carboxyl, nitro, sulfone, and hydroxyl groups.

[0040] As mentioned above, the divalent organic group Y may contain atoms other than carbon in its main chain. In one embodiment, the silane compound in general formula (1) contains an ester bond in Y. Examples of silane compounds in which Y contains an ester bond include the structures of general formula (I) and general formula (II).

[0041] [ka]

[0042] Silane compounds with x=3 in general formulas (I) and (II) are represented by the following general formulas (III) and (IV).

[0043] [ka]

[0044] R in general formulas (I) to (V) 1 , R 2 And x are the same as in general formula (1). R 4 and R 5 is the main chain atom It is a divalent organic group having three or more units, which may have branches and may contain atoms other than carbon in its main chain.

[0045] R 4 and R 5 Preferably, this is a linear alkylene having 3 to 10 carbon atoms, or a (poly)alkylene oxide having 3 to 10 atoms in the main chain. Specific examples of (poly)alkylene oxides having 3 to 10 atoms in the main chain include -C2H4-O-C2H4-, -C3H6-O-C2H4-, and -C2H4-O-C2H4-O-C2H4-.

[0046] <Method for synthesizing silane compounds> In general formula (1), one example of a method for synthesizing a silane compound in which Y is an ester bond is a method utilizing transesterification and hydrosilylation reactions. Specific examples of methods for synthesizing silane compounds using transesterification and hydrosilylation reactions are described below as Method 1 and Method 2.

[0047] Method 1: A method for performing a transesterification reaction between an ester compound and an alcohol, and a hydrosilylation reaction between the terminal double bond (-CH=CH2) and the SiH of the trialkoxysilane, using an ester compound having an alicyclic epoxy group, an alcohol having a terminal double bond, and a trialkoxysilane as starting materials. Method 2: A method for performing a transesterification reaction between an ester compound and an alcohol, and a hydrosilylation reaction between the terminal double bond (-CH=CH2) and the SiH of the trialkoxysilane, using an alcohol having an alicyclic epoxy group, an ester compound having a terminal double bond, and a trialkoxysilane as starting materials.

[0048] For example, the silane compound represented by the above general formula (IV) can be synthesized by Method 1. The silane compound represented by the above general formula (III) can be synthesized by Method 2.

[0049] In Method 1 and Method 2, the trialkoxysilane used as a raw material is of the general formula HSi(OR 1 ) is represented by 3. 1This is the same as in general formula (1), and is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. Multiple R 1 They may be the same or they may be different. 1 The alkyl group is preferably one having 3 or fewer carbon atoms, with a methyl group or an ethyl group being particularly preferred. Trimethoxysilane, triethoxysilane, and the like are suitably used as trialkoxysilanes.

[0050] In Method 1, an example of an ester compound having an alicyclic epoxy group that can be used as a raw material is methyl 3,4-epoxycyclohexane-1-carboxylate (CAS No. 41088-52-2).

[0051] In Method 1, examples of alcohols having a double bond at the end that can be used as a raw material include 2-propen-1-ol, 3-buten-1-ol, 4-penten-1-ol, 5-hexen-1-ol, 6-hepten-1-ol, 7-octen-1-ol, 8-nonen-1-ol, 9-decen-1-ol, ethylene glycol monovinyl ether, 4-hydroxybutyl vinyl ether, diethylene glycol monovinyl ether, and the like.

[0052] In Method 2, examples of alcohols having an alicyclic epoxy group that can be used as a raw material include 3,4-epoxycyclohexylmethanol and 3,4-epoxycyclohexanol.

[0053] In Method 2, examples of ester compounds having a double bond at the terminal end that can be used as raw materials include methyl 3-propenoate, methyl 4-pentenoate, methyl 5-hexenoate, methyl 6-heptenoate, methyl 7-octonate, methyl 8-nonenate, and methyl 9-decenoate.

[0054] All of the above-mentioned raw material compounds are commercially available. The transesterification and hydrosilylation reactions in Method 1 and Method 2 can both be carried out in the presence of a catalyst according to conventional methods.

[0055] As catalysts for transesterification reactions, any known transesterification catalyst can be appropriately selected. Examples of transesterification catalysts include organotin compounds such as dibutyltin oxide; metal oxides such as magnesium oxide, lead oxide, zirconium oxide, and zeolites; metal alkoxides such as titanium tetraisopropoxide, aluminum triisopropoxide, lithium methoxide, sodium methoxide, sodium ethoxide, and potassium t-butoxide; alkali metal amides such as lithium amide, sodium amide, and potassium amide; metal hydroxides such as magnesium hydroxide, lithium hydroxide, calcium hydroxide, sodium hydroxide, and potassium hydroxide; metal carbonates such as magnesium carbonate, lithium carbonate, sodium carbonate, and potassium carbonate; metal fatty acid salts such as potassium acetate, calcium laurate, and sodium stearate; and neutral or alkaline normal salts such as magnesium chloride.

[0056] In transesterification reactions, it is preferable to flow an inert gas such as nitrogen during the reaction to remove the resulting alcohol by distillation. The reaction temperature and reaction time for transesterification can be appropriately selected; for example, the transesterification reaction can be carried out by heating and stirring at 140°C for 6 hours.

[0057] For the hydrosilylation reaction, any known hydrosilylation catalyst can be selected. Examples of hydrosilylation catalysts include platinum-olefin complexes, chloroplatinic acid, elemental platinum, solid platinum supported on a support (alumina, silica, carbon black, polymer, etc.), Pt(acac)2, and platinum-vinylsiloxane complexes (e.g., Pt n (ViMe2SiOSiMe2Vi) n , Pt[(MeViSiO)4] mExamples of platinum-based catalysts include platinum-phosphine complexes (e.g., Pt(PPh3)4, Pt(PBu3)4), platinum-phosphite complexes (e.g., Pt[P(OPh)3]4, Pt[P(OBu)3]4), etc. In the formulas, Me represents a methyl group, Bu represents a butyl group, Vi represents a vinyl group, Ph represents a phenyl group, and n and m are integers. Other examples of platinum-based hydrosilylation catalysts include platinum-hydrocarbon complexes described in U.S. Patent No. 3,159601 and U.S. Patent No. 3,159662 by Ashby et al., and platinum alkoxide catalysts described in U.S. Patent No. 3,220972 by Lamoreaux et al.

[0058] Examples of hydrosilylation catalysts other than platinum include RhCl(PPh3)3, RhCl3, Rh / Al2O3, RuCl3, IrCl3, FeCl3, AlCl3, PdCl2·2H2O, NiCl2, TiCl4, etc. Hydrosilylation catalysts may be used alone or in combination of two or more. From the viewpoint of catalytic activity, platinum-based catalysts are preferred, and among them, chloroplatinic acid, platinum-olefin complexes, platinum-vinylsiloxane complexes, Pt(acac)2, etc. are preferred.

[0059] The reaction temperature and reaction time for the hydrosilylation reaction can be appropriately selected. When trimethoxysilane is used as the trialkoxysilane, for example, the hydrosilylation reaction can be carried out by heating and stirring at 80°C for 10 hours. When triethoxysilane is used as the trialkoxysilane, for example, the hydrosilylation reaction can be carried out by heating and stirring at 105°C for 10 hours.

[0060] In Method 1 and Method 2, the order of the transesterification reaction and the hydrosilylation reaction is not particularly limited.

[0061] In Method 1, if the transesterification reaction is carried out first, a compound is synthesized in which an alicyclic epoxy group and a molecular chain having -CH=CH2 at the end are linked via an ester bond by a transesterification reaction between an ester compound having an alicyclic epoxy group and an alcohol having a double bond at the end. By performing a hydrosilylation reaction between the -CH=CH2 at the end of this compound and the SiH of trialkoxysilane, a silane compound represented by general formula (IV) is obtained.

[0062] In Method 2, if the transesterification reaction is carried out first, a compound is synthesized in which an alicyclic epoxy group and a molecular chain having -CH=CH2 at the end are linked via an ester bond by a transesterification reaction between an alcohol having an alicyclic epoxy group and an ester compound having a double bond at the end. By performing a hydrosilylation reaction between the -CH=CH2 at the end of this compound and the SiH of trialkoxysilane, a silane compound represented by general formula (III) is obtained.

[0063] In Method 1, if the hydrosilylation reaction is carried out first, the hydrosilylation reaction between an alcohol having a terminal double bond and a trialkoxysilane is performed first, thereby forming the general formula HO-R 6 -Si(OR 1 A silane compound represented by )3 is obtained. 6 This is a divalent organic group. Transesterification of this silane compound with an ester compound having an alicyclic epoxy group yields a silane compound represented by general formula (IV).

[0064] In Method 2, if the hydrosilylation reaction is carried out first, the hydrosilylation reaction between the ester compound having a terminal double bond and the trialkoxysilane is performed first, thereby forming the general formula R 8 -OC(=O)-R 7 -Si(OR 1 A silane compound represented by )3 is obtained. 7 R is a divalent organic group, 8This is an alkyl group. By transesterification of the ester portion of this silane compound with an alcohol having an alicyclic epoxy group, a silane compound represented by general formula (III) is obtained.

[0065] In both cases, whether the transesterification reaction is carried out first or the hydrosilylation reaction is carried out first, a silane compound is obtained in which a Si atom and an alicyclic epoxy group (3,4-cyclohexyl group) are connected via an ester bond. From the viewpoint of suppressing side reactions such as ring opening of the epoxy group and the reaction of SiH with alcohol, and from the viewpoint of the stability of the intermediate product, it is preferable to carry out the hydrosilylation reaction after the transesterification reaction in both Method 1 and Method 2.

[0066] <Uses of silane compounds> The above-mentioned silane compound (1) has excellent storage stability and can be used as a silane coupling agent, as well as as an adhesion modifier for adhesives and sealants, and as a coating agent. Furthermore, since silane compound (1) has an alicyclic epoxy group and is polymerizable, it can also be used as a monomer component of resins.

[0067] Silane compound (1) exhibits excellent storage stability due to its suppressed hydrolysis in the absence of a catalyst. However, in the presence of a catalyst, the alkoxysilyl group undergoes hydrolysis, and the condensation of the hydrolysates produces a polyorganosiloxane compound. In other words, silane compound (1) can also be used as a raw material for polyorganosiloxane compounds.

[0068] [Polyorganosiloxane compounds] One aspect of the present invention relates to a polyorganosiloxane compound obtained by condensation of the above-mentioned silane compound (1). As described above, the silane compound (1) has two or three alkoxysilyl groups in one molecule, and is Si-OR 1 Because it is hydrolyzable, a polyorganosiloxane compound is produced by condensation of silane compound (1). The polyorganosiloxane compound obtained by condensation of silane compound (1) contains a structure represented by general formula (11).

[0069] [ka]

[0070] In general formula (11), Y is the same as in general formula (1), and is a divalent organic group with 5 or more atoms in the main chain. Y may also contain an ester bond.

[0071] In the synthesis of polyorganosiloxane compounds, silane compounds other than silane compound (1) may be used. Examples of silane compounds other than silane compound (1) include silane compounds represented by the following general formula (2) (hereinafter sometimes referred to as "silane compound (2)"). R 3 -(Si(OR 1 ) x R 2 3-x ) …(2)

[0072] By condensing a mixture of silane compound (1) and silane compound (2), a polyorganosiloxane compound is obtained that includes the structure represented by general formula (12) in addition to the structure represented by general formula (11). [R 3 -Si] …(12)

[0073] R in general formula (2) 1 , R 2 and x are R in general formula (1) 1 , R 2 And the same applies to x. R in general formulas (2) and (12) 3 R is a monovalent organic group. 3 This refers to a group containing a substituted or unsubstituted double bond, a group containing a substituted or unsubstituted cycloalkyl group, a group containing a substituted or unsubstituted aromatic ring, a substituted or unsubstituted alkyl group, a group having a glycidyl group, a group having an oxetanyl group, a hydrogen atom, or a monovalent organic group represented by the following general formula (3).

[0074] [ka]

[0075] In general formula (3), W is a divalent organic group with 4 or fewer atoms in the main chain, and W is bonded to a Si atom.

[0076] When silane compound (2) is used in addition to silane compound (1) as a raw material for polyorganosiloxane compounds, silane compound (2) is, in general formula (2), R 3 A silane compound in which is a monovalent organic group represented by general formula (3) is preferred. That is, the silane compound (2) is preferably one having an alicyclic epoxy group (3,4-epoxycyclohexyl group).

[0077] R 3 Examples of silane compounds (2) in which is a monovalent organic group represented by general formula (3) include 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyldimethylmethoxysilane, 3-(3,4-epoxycyclohexyl)propyltrimethoxysilane, 3-(3,4-epoxycyclohexyl)propimethyldimethoxysilane, 3-(3,4-epoxycyclohexyl)propyldimethylmethoxysilane, and the like.

[0078] As a silane compound, R 3 When a silane compound (2) which is a monovalent organic group represented by general formula (3) is used, the polyorganosiloxane compound obtained by condensation contains a structure represented by general formula (13).

[0079] [ka]

[0080] As silane compound (2), a silane compound that does not contain an alicyclic epoxy group may be used. As silane compound (2), a silane compound containing an alicyclic epoxy group (R 3 Both a silane compound in which the group is a monovalent organic group represented by general formula (3) and a silane compound that does not contain an alicyclic epoxy group may be used. As the silane compound that does not contain an alicyclic epoxy group, one having a glycidyl group is preferred.

[0081] A specific example of a silane compound having a glycidyl group is R of general formula (2). 3 Examples include those in which the group is a glycidyloxyalkyl group. Examples of glycidyloxyalkyl groups include the 3-glycidyloxypropyl group and the 8-glycidyloxyoctyl group.

[0082] In general formulas (1) and (2), x is preferably 3. Because x=3, the polyorganosiloxane compound has a three-dimensional structure, which tends to improve the hardness of the cured film (hard coat layer) obtained by curing the polyorganosiloxane compound. A silane compound with x=2 and a silane compound with x=3 may be used in combination. Furthermore, in addition to silane compounds with x=2 or 3, a silane compound with x=1 may be used for purposes such as adjusting the molecular weight of the polyorganosiloxane compound obtained by condensation.

[0083] (Hydrolysis and condensation of silane compounds) By reacting the above silane compounds with water, the Si-OR of the silane compounds is obtained. 1 The silane compound undergoes hydrolysis, and the hydrolyzates condense to form Si-O-Si bonds, generating a condensate of the silane compound (polyorganosiloxane compound). The amount of water required for the hydrolysis and condensation reactions is determined by the -OR bonded to the Si atom. 1 0.3 to 10 equivalents per 1 equivalent of the base is preferable, 0.5 to 5 equivalents is more preferable, and 1 to 3 equivalents is even preferable. If the amount of water is excessively small, the OR will remain without hydrolysis. 1Due to the large number of groups and the low molecular weight of the polyorganosiloxane compound, the hard coat layer tends to lack sufficient hardness. If the amount of water is excessively high, the reaction rates of hydrolysis and condensation reactions are high, leading to the formation of high molecular weight condensates, which tends to reduce the transparency and flexibility of the hard coat layer.

[0084] From the viewpoint of increasing the hardness of the cured film (hard coat layer), the weight-average molecular weight of the polyorganosiloxane compound is preferably 500 or higher. Furthermore, from the viewpoint of suppressing volatilization, a weight-average molecular weight of 500 or higher is also preferable. On the other hand, if the molecular weight is excessively high, turbidity may occur due to decreased compatibility with other compositions. Therefore, a weight-average molecular weight of 20,000 or less is preferable. The molecular weight of the polyorganosiloxane compound can be controlled by selecting the amount of water used in the reaction, the type and amount of catalyst. For example, increasing the amount of water tends to increase the molecular weight.

[0085] From the perspective of suppressing side reactions during photocuring and the hardness of the cured product, the residual OR per silane compound unit in polyorganosiloxane compounds 1 A small number of groups is preferable. 1 The number of groups is, on average, 2 or less. OR per Si atom 1 The number of groups is preferably 1.5 or less on average, and more preferably 1.0 or less. The number of OR groups per Si atom in polyorganosiloxane compounds. 1 The number of groups may be an average of 0.01 or more, 0.05 or more, 0.1 or more, 0.2 or more, or 0.3 or more. The flexural resistance of the cured film may be increased when alkoxy groups remain in the polyorganosiloxane compound.

[0086] From the viewpoint of improving curing speed and hardness of the hard coat layer, polyorganosiloxane compounds with a high epoxy group content are preferable. The remaining epoxy group percentage is preferably 20% or more, more preferably 40% or more, even more preferably 60% or more, and may be 80% or more, 90% or more, or 95% or more. 1 The remaining percentage of the group and the remaining percentage of the epoxy group are 1 This can be calculated by 1H-NMR measurement.

[0087] In the hydrolysis and condensation reactions of silane compounds, it is preferable to carry out the reactions under neutral or basic conditions from the viewpoint of suppressing ring-opening of epoxy groups. In particular, from the viewpoint of suppressing deactivation due to ring-opening of epoxy groups before and after the hydrolysis and condensation reactions, and in the storage environment of the polyorganosiloxane compound obtained by condensation, it is preferable to carry out the hydrolysis and condensation reactions in the presence of a neutral salt catalyst.

[0088] Examples of neutral salt catalysts include salts composed of an acid and a base, with salts composed of an alkali metal or alkaline earth metal cation and a halogen anion being preferred. Specific examples of neutral salts include lithium chloride, sodium chloride, potassium chloride, beryllium chloride, magnesium chloride, calcium chloride, lithium bromide, sodium bromide, potassium bromide, beryllium bromide, magnesium bromide, calcium bromide, lithium iodide, sodium iodide, potassium iodide, beryllium iodide, magnesium iodide, and calcium iodide.

[0089] When a neutral salt catalyst is used for the hydrolysis and condensation of silane compounds, the neutral salt catalyst may remain in the polyorganosiloxane compound. The amount of neutral salt remaining in the polyorganosiloxane compound may be 1 ppm to 10,000 ppm, 50 ppm to 5,000 ppm, or 100 ppm to 1,000 ppm.

[0090] As described above, the polyorganosiloxane compound obtained by the condensation of silane compound (1) contains a structure represented by general formula (11). The hard coat layer formed by curing the polyorganosiloxane compound containing the structure represented by general formula (11) can achieve both high surface hardness and excellent flexibility. Furthermore, hard coat films having this hard coat layer tend to have reduced curling.

[0091] From the viewpoint of improving surface hardness and flexural resistance, as well as suppressing curling, the ratio of the structure represented by general formula (11) to the total number of Si atoms in the polyorganosiloxane compound is preferably 0.3 or more, more preferably 0.4 or more, even more preferably 0.5 or more, and may be 0.6 or more, 0.7 or more, 0.8 or more, 0.9 or more, or 0.95 or more.

[0092] From the viewpoint of improving the mechanical strength of the cured product, it is preferable that the number of epoxy groups contained in one molecule of the polyorganosiloxane compound be as large as possible, and in particular, it is preferable that the number of alicyclic epoxy groups be large. The ratio of the total number of structures represented by general formula (11) and general formula (13) to the total number of Si atoms in the polyorganosiloxane compound is preferably 0.4 or more, more preferably 0.5 or more, even more preferably 0.6 or more, and may be 0.7 or more, 0.8 or more, 0.9 or more, 0.95 or more, or 1.

[0093] From the viewpoint of improving the flexibility of the hard coat layer, the ratio of the structure represented by general formula (13) to the total number of Si atoms in the polyorganosiloxane compound is preferably 0.5 or less, more preferably 0.3 or less, even more preferably 0.2 or less, and may be 0.1 or less, 0.05 or less, or 0.

[0094] In polyorganosiloxane compounds, the ratio of the structure represented by general formula (11) to the total of the structures represented by general formula (13) is preferably 0.5 or higher. More preferably, the ratio of the structure represented by general formula (11) to the total of the structures represented by general formula (13) is 0.7 or higher, and may be 0.8 or higher, 0.9 or higher, 0.95 or higher, or 1. The higher the ratio of the structure represented by general formula (11), that is, the higher the ratio of structures in which Si atoms and 3,4-epoxycyclohexyl groups are bonded via long-chain spacers with 5 or more atoms in the main chain, the more the hard coat layer formed by curing the polyorganosiloxane compound tends to have superior flexural resistance.

[0095] On the other hand, when the polyorganosiloxane compound contains the structure of general formula (13), the hardness of the hard coat layer formed by curing tends to be higher. From the viewpoint of improving the hardness of the hard coat layer, the ratio of the structure of general formula (13) to the sum of the structures of general formula (11) and general formula (13) may be 0.05 or higher, 0.1 or higher, or 0.2 or higher.

[0096] In the hydrolysis and condensation reactions of silane compounds, the alkoxysilyl group-OR 1 While the Si group is involved in the reaction, other functional groups bonded to the Si atom do not react, except for side reactions such as ring-opening of the epoxy group. Therefore, in the polyorganosiloxane compounds obtained by the condensation of silane compounds, the structure of part (11) of silane compound (1) and the structure of part (12) of silane compound (2) are preserved before and after the reaction.

[0097] Therefore, the ratio of the structure of general formula (11) to the total number of Si atoms in the polyorganosiloxane compound is approximately equal to the ratio of the silane compound of general formula (1) to the total amount of the silane compound. In other words, by adjusting the charging ratio of the silane compound when synthesizing the polyorganosiloxane compound, a polyorganosiloxane compound having the structure represented by general formula (11) in the above ratio can be obtained.

[0098] The ratio of silane compound (1) to the total amount of silane compounds is preferably 0.3 or higher, more preferably 0.4 or higher, even more preferably 0.5 or higher, and may be 0.6 or higher, 0.7 or higher, 0.8 or higher, 0.9 or higher, 0.95 or higher, or 1.

[0099] When a silane compound (2) that does not have an alicyclic epoxy group is used in addition to silane compound (1), the molar ratio of silane compound (2) to silane compound (1) is preferably 2 or less, more preferably 1 or less, even more preferably 0.4 or less, particularly preferably 0.2 or less, and may also be 0.1 or less.

[0100] Silane compounds (2) having an alicyclic epoxy group, i.e., R in general formula (2) 3 When using a silane compound which is a monovalent organic group represented by general formula (3), from the viewpoint of the flexural resistance of the hard coat layer, the molar ratio of silane compound (2) to the total amount of silane compound is preferably 0.5 or less, more preferably 0.3 or less, even more preferably 0.2 or less, and may be 0.1 or less or 0.05 or less.

[0101] [Hard coat composition] One aspect of the present invention relates to a hard coat composition comprising the above-mentioned polyorganosiloxane compound. The above-mentioned polyorganosiloxane compound can be used as a curable resin material for forming a hard coat layer because the alicyclic epoxy group in the structure of general formula (11) is photocurable.

[0102] The hard coat composition contains the above-mentioned polyorganosiloxane compound as a curable resin component, and further contains a photocationic polymerization initiator. The hard coat composition may further contain leveling agents, reactive diluents, photosensitizers, particles, and other additives as solids (non-volatile components). From the viewpoint of forming a hard coat layer with excellent mechanical strength, the content of the polyorganosiloxane compound in the hard coat composition is preferably 40 parts by weight or more, more preferably 50 parts by weight or more, and even more preferably 60 parts by weight or more, based on 100 parts by weight of the total solids (non-volatile components).

[0103] <Photocation polymerization initiator> A photocationic polymerization initiator is a compound that generates acid upon irradiation with active energy rays (a photoacid generator). The acid generated from the photoacid generator promotes the ring-opening and polymerization reactions of the epoxy groups of the polyorganosiloxane compound, forming intermolecular crosslinks and curing the hard coat material.

[0104] Examples of photocationic polymerization initiators include strong acids such as toluenesulfonic acid, antimony hexafluoride, boron tetrafluoride, phosphorus hexafluoride, fluoroalkyl phosphorus fluoride, and fluoroalkyl gallium fluoride; onium salts such as sulfonium salts, ammonium salts, phosphonium salts, iodonium salts, and selenium salts; iron-allene complexes; silanol-metal chelate complexes; sulfonic acid derivatives such as disulfones, disulfonyldiazomethanes, disulfonylmethanes, sulfonylbenzoylmethanes, imidosulfonates, and benzoin sulfonates; and organic halogen compounds. Among these, aromatic sulfonium salts or aromatic iodonium salts are preferred due to their high stability in hard coat compositions.

[0105] The amount of photocationic polymerization initiator in the hard coat composition is preferably 0.05 to 10 parts by weight, more preferably 0.1 to 5 parts by weight, and even more preferably 0.2 to 2 parts by weight, per 100 parts by weight of the polyorganosiloxane compound.

[0106] <Leveling agent> The hard coat composition may contain a leveling agent. Silicone-based leveling agents and fluorine-based leveling agents are preferred. The inclusion of a leveling agent can be expected to reduce the surface tension of the hard coat composition and improve its surface smoothness.

[0107] The leveling agent content in the hard coat composition is preferably 0.001 to 10 parts by weight, more preferably 0.01 to 5 parts by weight, and even more preferably 0.05 to 1 part by weight, per 100 parts by weight of the polyorganosiloxane compound.

[0108] <Reactive Diluent> The hard coat composition may contain a reactive diluent. Examples of reactive diluents include cationic polymerizable compounds other than the polyorganosiloxane compounds mentioned above. Compounds having cationic polymerizable functional groups are used as reactive diluents for photocationic polymerization. Examples of cationic polymerizable functional groups of reactive diluents include epoxy groups, vinyl ether groups, oxetane groups, and alkoxysilyl groups. Among these, those having epoxy groups are preferred as reactive diluents because of their high reactivity with the epoxy groups of polyorganosiloxane compounds.

[0109] The content of the reactive diluent in the hard coat composition is preferably 100 parts by weight or less, and more preferably 50 parts by weight or less, per 100 parts by weight of the polyorganosiloxane compound.

[0110] <Photosensitizer> The hard coat composition may contain a photosensitizer for purposes such as improving the photosensitivity of the photocationic polymerization initiator (photoacid generator). The photosensitizer may be either a type that improves the photosensitivity of the photocationic polymerization initiator by absorbing light in wavelength ranges that the photocationic polymerization initiator cannot absorb, or a type that improves the photosensitivity of the photocationic polymerization initiator even though there is no significant difference in the wavelength range absorbed by the photocationic polymerization initiator. For the type of photosensitizer that absorbs light in wavelength ranges that the photocationic polymerization initiator cannot absorb, it is preferable to have a strong absorption in a wavelength range different from the absorption wavelength range of the photocationic polymerization initiator. Examples of photosensitizers include anthracene derivatives, benzophenone derivatives, thioxanthone derivatives, anthraquinone derivatives, benzoin derivatives, and naphthalene derivatives.

[0111] The amount of photosensitizer in the hard coat composition is preferably 500 parts by weight or less, more preferably 100 parts by weight or less, and even more preferably 50 parts by weight or less, per 100 parts by weight of the above-mentioned photocationic polymerization initiator.

[0112] <Particle> The hard coat composition may contain particles for the purpose of adjusting film properties such as surface hardness and flexibility. The particles may be organic particles, inorganic particles, organic-inorganic composite particles, etc., as appropriate. The particles may be surface-modified, and polymerizable functional groups may be introduced through surface modification.

[0113] The average particle diameter is, for example, about 5 nm to 10 μm. From the viewpoint of improving the transparency of the hard coat layer, the average particle diameter is preferably 1000 nm or less, more preferably 500 nm or less, even more preferably 300 nm or less, and particularly preferably 100 nm or less. The particle diameter can be measured using a laser diffraction / scattering particle size distribution analyzer, and the median diameter based on volume is taken as the average particle diameter.

[0114] The particle content in the hard coat composition is preferably 100 parts by weight or less, and more preferably 50 parts by weight or less, per 100 parts by weight of the polyorganosiloxane compound.

[0115] (solvent) The hard coat composition may be solvent-free or may contain a solvent. If the hard coat composition contains a solvent, it is preferable that the solvent does not dissolve the transparent resin film 1 as the substrate. On the other hand, using a solvent that has enough solubility to swell the resin film may improve the adhesion between the transparent resin film 1 and the hard coat layer 3. The solvent content is preferably 500 parts by weight or less, more preferably 300 parts by weight or less, and even more preferably 100 parts by weight or less, per 100 parts by weight of the polyorganosiloxane compound.

[0116] (Other ingredients) The hard coat composition may contain additives such as inorganic pigments, organic pigments, surface modifiers, surface modifiers, plasticizers, dispersants, wetting agents, thickeners, defoamers, and UV stabilizers. The hard coat composition may also contain thermoplastic, thermosetting, or photocurable resin materials other than the polyorganosiloxane compounds mentioned above. If the polyorganosiloxane compound and / or the resin material other than the polyorganosiloxane compound is radically polymerizable, the hard coat composition may contain a radical polymerization initiator in addition to the photocationic polymerization initiator.

[0117] [Hard coat film] One aspect of the present invention is a hard coat film comprising a hard coat layer made of a cured product of the above-mentioned hard coat composition on a transparent resin film.

[0118] Figure 1 is a cross-sectional view of a hard coat film according to one embodiment of the present invention. The hard coat film 11 comprises a hard coat layer 3 on one main surface of a transparent resin film 1. The hard coat layer 3 is a cured product layer containing the cured product of the polyorganosiloxane compound described above. As shown in Figure 2, the hard coat film may also comprise a top coat layer 5 on the hard coat layer 3. The hard coat film may have the hard coat layer on one surface of the transparent resin film, or it may have the hard coat layer on both sides of the transparent resin film.

[0119] <Transparent resin film> The transparent resin film 1 is a resin substrate that serves as the base for forming the hard coat layer 3. The transparent resin film 1 is preferably transparent. The total light transmittance of the transparent resin film 1 is preferably 80% or more, more preferably 85% or more, and even more preferably 90% or more. The haze of the transparent resin film 1 is preferably 2% or less, and more preferably 1% or less.

[0120] The thickness of the transparent resin film 1 is, for example, about 1 to 1000 μm. Preferably, the thickness of the transparent resin film 1 is 5 to 500 μm, more preferably 10 to 200 μm, and even more preferably 15 to 150 μm. If the thickness is too small, the hardness will be insufficient, and if the thickness is too large, the flexibility will tend to be poor.

[0121] Examples of resin materials that make up the transparent resin film 1 include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), acrylic resins such as polymethyl methacrylate (PMMA), cellulose resins such as triacetylcellulose (TAC), polycarbonate, polyamide, transparent polyimide, and cyclic polyolefin.

[0122] Among these, polyesters such as PET, cellulose-based resins such as TAC, and polyimides are preferred as resin materials due to their excellent transparency and mechanical strength. When hard coat films are used as cover windows for displays, the film substrate is required to have excellent heat resistance and mechanical strength, so transparent polyimides are particularly preferred as the resin material for transparent resin films. While general all-aromatic polyimides are colored yellow or brown, transparent polyimides with high visible light transmittance can be obtained by introducing alicyclic structures, bent structures, fluorine substituents, etc.

[0123] The transparent resin film 1 may contain two or more resin materials. The transparent resin film may also contain stabilizers such as UV absorbers and radical trapping agents for the purpose of providing weather resistance, and dyes and pigments such as bluing agents for the purpose of adjusting the color tone.

[0124] The transparent resin film 1 may be a single layer or a multilayer structure. For example, the transparent resin film may be a laminate formed by bonding multiple films together, and functional layers such as an easy-adhesion layer, an antistatic layer, or an anti-reflective layer may be provided on the surface of the film (the surface where the hard coat layer 3 is formed and / or the surface where the hard coat layer is not formed).

[0125] The thickness of the transparent resin film 1 is not particularly limited and can be appropriately selected from, for example, a range of 1 to 1000 μm, preferably 5 to 500 μm, more preferably 10 to 200 μm, and even more preferably 15 to 150 μm.

[0126] <Hard coat layer> A hard coat layer 3 is formed by applying a hard coat composition onto a transparent resin film 1 and curing it. The hard coat composition used to form the hard coat layer 3 contains a polyorganosiloxane compound as a curable resin component.

[0127] A hard coat layer 3 is formed on the transparent resin film 1 by applying a hard coat composition onto the transparent resin film 1, drying and removing the solvent as necessary, and then curing the hard coat composition by irradiating it with active energy rays.

[0128] Methods for applying the hard coat composition include roll coating such as bar coating, gravure coating, and comma coating; die coating such as slot die coating and fountain die coating; spin coating; spray coating; and dip coating. Before applying the hard coat composition, the surface of the transparent resin film may be subjected to surface treatment such as corona treatment or plasma treatment. Alternatively, an easy-adhesion layer may be provided on the surface of the transparent resin film 1.

[0129] Upon irradiation with active energy rays or heat, an acid is generated from the cationic polymerization initiator, causing ring-opening and cationic polymerization of the epoxy groups of the polyorganosiloxane compound, leading to curing. If the additives in the hard coat composition, such as reactive diluents or particles, contain epoxy groups, polymerization reactions occur not only between polyorganosiloxane compounds but also between the polyorganosiloxane compounds and the additives.

[0130] Ultraviolet light is preferred as the active energy ray. The cumulative irradiation dose of the active energy ray is, for example, 50 to 10,000 mJ / cm². 2The curing temperature is approximate and can be set according to the type and amount of photocationic polymerization initiator, the thickness of the film, etc. The curing temperature is not particularly limited, but is usually 150°C or lower, and may be 100°C or lower or 90°C or lower.

[0131] The thickness of the hard coat layer 3 is preferably 0.5 μm or more, more preferably 2 μm or more, even more preferably 3 μm or more, and particularly preferably 5 μm or more. The thickness of the hard coat layer 3 is preferably 100 μm or less, and more preferably 80 μm or less. The greater the thickness of the hard coat layer, the more the mechanical properties such as surface hardness tend to improve. On the other hand, if the thickness of the hard coat layer is excessively large, the flexibility of the hard coat layer may decrease.

[0132] The total thickness of the transparent resin film 1 and the hard coat layer 3 is preferably 10 to 500 μm, more preferably 15 to 250 μm, and even more preferably 20 to 200 μm. If the thickness is too small, the mechanical strength may be insufficient, and if the thickness is too large, the transparency and flexibility may be insufficient. The ratio of the thickness D1 of the transparent resin film 1 to the thickness D3 of the hard coat layer 3, D3 / D1, is, for example, about 0.01 to 10.

[0133] [Top coat layer] As shown in Figure 2, a topcoat layer 5 may be provided on the surface of the hardcoat layer 3. For example, by providing a topcoat layer 5 containing a fluorine compound on the outermost surface of the hardcoat film, scratch resistance and stain resistance are improved.

[0134] <Fluorine compounds> The fluorine compounds constituting the topcoat layer contain one or more fluorine atoms in their molecules. Preferably, the fluorine compounds contain a perfluoroalkyl group. Examples of compounds containing a perfluoroalkyl group include perfluoroalkyl compounds, perfluoroalkyl ether compounds, perfluoroether compounds, and perfluoropolyether compounds.

[0135] The fluorine compound constituting the topcoat layer is preferably a condensate of a compound having an alkoxysilyl group and a perfluoroalkyl group in its molecule, and the film is formed by increasing the molecular weight through hydrolysis and condensation of the alkoxysilyl group.

[0136] Perfluoroalkyl groups are formed by replacing all hydrogen atoms in an alkyl group with fluorine atoms, such as CF3 (CF2). n It is represented by -. From the viewpoint of condensation reactivity, the trialkoxysilyl group is preferred as the alkoxysilyl group, and among these, the triethoxysilyl group or the trimethoxysilyl group is preferred, and the trimethoxysilyl group is particularly preferred.

[0137] Compounds having an alkoxysilyl group and a perfluoroalkyl group in the molecule preferably have a fluoroalkyl ether structure, and oligomers having repeating units of fluoroalkyl ether are preferred.

[0138] Examples of fluoroalkyl ether structures include -(OC4F8)-, -(OC3F6)-, -(OC2F4)-, and -(OCF2)-. The perfluoroalkyl group of the fluoroalkyl ether may be linear or branched, but a linear structure is preferable from the viewpoint of scratch resistance.

[0139] The number-average molecular weight of the oligomer is preferably 1,000 to 50,000, more preferably 3,000 to 20,000, and even more preferably 5,000 to 10,000. If the number-average molecular weight is less than 1,000, the scratch resistance may be poor, and if it is greater than 50,000, it may be difficult to apply the composition.

[0140] Perfluoroalkyl group-containing compounds may also contain substituents other than perfluoroalkyl groups or repeating units other than fluoroalkyl ethers. Examples of substituents include alkyl groups and fluoroalkyl groups in which some of the hydrogen atoms of the alkyl group are substituted with fluorine atoms (i.e., fluoroalkyl groups other than perfluoroalkyl groups). From the viewpoint of scratch resistance, perfluoroalkyl group-containing compounds are preferable as the proportion of hydrogen atoms of the alkyl group substituted with fluorine increases.

[0141] <Formation of the top coat layer> The method for forming the topcoat layer 5 is not particularly limited, and wet methods such as roll coating (bar coating, gravure coating, comma coating, etc.), die coating (slot die coating, fountain die coating, etc.), spin coating, spray coating, dip coating, etc., and dry methods such as vacuum deposition, sputtering, and CVD can be used. When forming a film by condensing a compound having an alkoxysilyl group and a perfluoroalkyl group in its molecule, a wet method is preferred from the viewpoint of promoting hydrolysis, etc.

[0142] Before forming the topcoat layer 5 on the hardcoat layer 3, surface treatments such as corona treatment, plasma treatment, or ion beam treatment may be performed. Alternatively, a primer layer may be provided on the hardcoat layer 3, and the topcoat layer 5 may be formed on top of it. Examples of materials for the primer layer include metal oxides such as silicon dioxide, titanium dioxide, aluminum oxide, and zirconium oxide; and organic-inorganic hybrid materials which are hydrolysis condensates of alkoxysilanes.

[0143] The surface treatment of the hard coat layer 3 generates hydroxyl groups, carboxyl groups, carbonyl groups, silanol groups, etc., which improves adhesion with compounds containing alkoxysilyl groups and perfluoroalkyl groups (components of the top coat layer 5), and tends to improve scratch resistance and stain resistance.

[0144] For surface treatment, corona treatment is preferred because it can be easily performed under atmospheric pressure. The corona treatment density is 1 W·min / m³. 2The above is preferable, 10 W·min / m 2 The above is more preferable: 30 W·min / m 2 More than 100W min / m 2 Above or above 500W·min / m 2 It may be greater than or equal to 3000W·min / m 2 The following is preferable: 600W·min / m 2 The following are preferable: If the processing density is too low, the adhesion improvement effect from the surface treatment may be insufficient, and if the processing density is too high, the hard coat layer may deteriorate.

[0145] When forming a scratch-resistant layer by a wet process, it is preferable to use a composition obtained by diluting a compound (oligomer) having an alkoxysilyl group and a perfluoroalkyl group in its molecule with a solvent. From the viewpoint of compound solubility and solvent volatility, preferred solvents include perfluoroaliphatic hydrocarbons having 5 to 12 carbon atoms such as perfluorohexane, perfluoromethylcyclohexane, and perfluoro-1,3-dimethylcyclohexane; polyfluoroaromatic hydrocarbons such as bis(trifluoromethyl)benzene; and hydrofluoroethers (HFE) such as perfluoropropyl methyl ether (C3F7OCH3), perfluorobutyl methyl ether (C4F9OCH3), perfluorobutyl ethyl ether (C4F9OC2H5), and perfluorohexyl methyl ether (C2F5CF(OCH3)C3F7). The perfluoroalkyl group and alkyl group of the hydrofluoroether may be linear or branched. Hydrofluoroethers are preferred as solvents, with perfluorobutyl methyl ether (C4F9OCH3) and perfluorobutyl ethyl ether (C4F9OC2H5) being preferred. The solvent may be a mixture of two or more solvents.

[0146] In addition to the perfluoro compounds mentioned above, the composition may also contain other additives such as perfluoroalkyl group-containing compounds, typified by fluoroalkyl ether oligomers that do not have an alkoxysilyl group in their molecule, fluorinated oils, and silicone oils. The inclusion of fluorinated oils or silicone oils may improve scratch resistance and stain resistance.

[0147] The composition may contain catalysts such as acids, bases, or metal-organic compounds. The inclusion of a catalyst may promote the reaction between the alkoxysilyl groups and the functional groups on the hard coat layer surface, potentially improving the adhesion of the topcoat layer 5 to the hard coat layer 3. The composition may also contain water. The presence of water may hydrolyze the alkoxysilyl groups, promoting their reaction with the functional groups on the hard coat layer surface, potentially improving the adhesion of the topcoat layer 5 to the hard coat layer 3.

[0148] Commercially available scratch-resistant coating compositions such as Daikin Industries' "OPTOOL UD509" and "OPTOOL DSX-E" may be used. Alternatively, solvents and additives may be added to commercially available coating compositions before use.

[0149] The solid content concentration of the compound (oligomer) having an alkoxysilyl group and a perfluoroalkyl group in the molecule in the composition is not particularly limited, but from the viewpoint of coatability, it is preferably 20% by weight or less, more preferably 10% by weight or less, even more preferably 5% by weight or less, and may be 1% by weight or less or 0.5% by weight or less. If the solid content concentration is excessively high, the coating film may become cloudy.

[0150] It is preferable to apply the composition onto the hard coat layer 3 and then heat it. Heating promotes the condensation of compounds having an alkoxysilyl group and a perfluoroalkyl group within the alkoxysilyl group molecule. The heating temperature is preferably 30°C or higher, more preferably 60°C or higher, and may be 100°C or higher or 130°C or higher. The heating temperature is usually 170°C or lower.

[0151] The thickness of the topcoat layer 5 is not particularly limited, but is preferably 1 nm or more, more preferably 5 nm or more, even more preferably 6 nm or more, and particularly preferably 10 nm or more. The thickness of the scratch-resistant layer is preferably 1000 nm or less, more preferably 100 nm or less, and may be 50 nm or less, 45 nm or less, 40 nm or less, 35 nm or less, or 30 nm or less. If the thickness of the scratch-resistant layer is excessively small, scratch resistance and stain resistance may be insufficient, and if the thickness is excessively large, the transparency of the coating film may decrease due to clouding, etc.

[0152] In a scratch-resistant layer formed by a composition containing a compound having an alkoxysilyl group and a perfluoroalkyl group in its molecule, it is preferable that the alkoxysilyl group in the perfluoroalkyl compound undergoes hydrolysis and condensation. When hydrolysis and condensation are promoted by heating after coating the composition, the hydroxyl group generated by the hydrolysis of the alkoxysilyl group can condense not only with the alkoxysilyl group of other perfluoro compounds (and the hydroxyl group generated by their hydrolysis) but also with the functional groups on the surface of the hard coat layer 3 to form covalent bonds. Therefore, the perfluoroalkyl compound is firmly immobilized on the hard coat layer 3, and scratch resistance is expected to improve.

[0153] In particular, the hard coat layer formed by curing a polyorganosiloxane compound having epoxy groups has hydroxyl groups (silanol groups) generated by hydrolysis during the condensation of the silane compound, and also has hydroxyl groups generated by ring-opening of the epoxy group during curing. These hydroxyl groups can undergo condensation reactions with the alkoxysilyl groups of the perfluoroalkyl compound. Furthermore, the polyorganosiloxane compound constituting the hard coat layer is an organic compound containing Si atoms, similar to the alkoxysilyl groups of the perfluoro compound, and they have a high affinity for each other. In addition, the alkoxysilyl groups and silanol groups of the polyorganosiloxane compound can condense with the alkoxysilyl groups of the perfluoro compound, which is thought to improve the adhesion between the hard coat layer 3 and the top coat layer 5.

[0154] [Characteristics of hard coat film] A hard coat film, in which a hard coat layer 3 containing a cured polyorganosiloxane compound having a structure represented by general formula (1) is provided on a transparent resin film 1, has high surface hardness and excellent flexibility.

[0155] The pencil hardness of the hard coat layer 3 is preferably HB or higher, more preferably H or higher, even more preferably 2H or higher, even more preferably 3H or higher, and may also be 4H or higher. The greater the thickness of the hard coat layer 3, the higher the surface hardness tends to be.

[0156] The surface hardness tends to increase with increasing amounts of alicyclic epoxy groups in polyorganosiloxane compounds. Furthermore, the surface hardness tends to increase with a smaller number of atoms in the Y main chain of general formula (11). From the viewpoint of increasing the surface hardness of the hard coat film, the number of atoms in the Y main chain is preferably 16 or less, more preferably 10 or less, even more preferably 8 or less, and may also be 6 or less.

[0157] When a cylindrical mandrel test is performed on the hard coat film with the hard coat layer 3-forming surface facing outward, in accordance with JIS-K5600, it is preferable that the mandrel diameter φ at which no cracks occur in the hard coat layer (the mandrel diameter at the time of the test immediately before cracking occurs) is small. φ is preferably 6 mm or less, more preferably 4 mm or less, and may also be 3 mm or less or 2 mm or less.

[0158] When a hard coat film is subjected to a dynamic bending test at a radius of 3 mm in a 25°C environment with the hard coat layer 3-formed surface facing outward, it is preferable that the number of bending cycles before cracks appear in the hard coat layer (bending resistance) is 1,000 or more. More preferably, the bending resistance is 10,000 or more, and may be 50,000 or more, 100,000 or more, or 200,000 or more.

[0159] The polyorganosiloxane compound having the structure represented by general formula (11) enhances the flexural resistance of the hard coat film, and tends to have a smaller φ and a greater number of flexural cycles. Furthermore, the greater the number of atoms in the Y main chain in general formula (11), the greater the flexural resistance tends to be.

[0160] From the standpoint of ease of handling, it is preferable that the hard coat film has minimal curling. For example, it is preferable that the hard coat film does not form a tube when cut into 3cm squares. When a 3cm square piece of hard coat film is placed on a horizontal surface, the average amount of lift at the four vertices of the hard coat film is preferably 8mm or less, more preferably 6mm or less, and even more preferably 4mm or less.

[0161] Polysiloxane-based hard coat layers formed by curing polyorganosiloxane compounds containing alicyclic epoxy groups exhibit excellent hardness but tend to have poor flexural resistance. On the other hand, polysiloxane-based hard coat layers formed by curing polyorganosiloxane compounds containing glycidyl groups have excellent flexural resistance but tend to exhibit large curing shrinkage and significant curling.

[0162] In contrast, by curing a polyorganosiloxane compound having the structure represented by the general formula (11) above to form a hard coat layer, a hard coat film with excellent flexibility and minimal curling can be obtained.

[0163] Polyorganosiloxane compounds obtained by condensation of silane compounds containing alicyclic epoxy groups retain their alicyclic structure even after curing by ring-opening polymerization of the epoxy groups. Therefore, the reduction in molecular volume due to curing is minimal, and in fact, the volume tends to increase during curing. As a result, curing shrinkage is less likely to occur, which can contribute to suppressing curling of hard coat films. Furthermore, because the alicyclic structure is more rigid than the chain structure, the hardness of the hard coat layer tends to improve.

[0164] Furthermore, polyorganosiloxane compounds having the structure represented by general formula (11) retain their molecular structure flexibility even after curing due to the reaction of the epoxy group, because an organic group Y with a specific chain length exists between the polymerizable functional group, the alicyclic epoxy group (3,4-epoxycyclohexyl group), and the Si atom. Therefore, it is thought that the hard coat layer composed of the cured polyorganosiloxane compound exhibits excellent flexural resistance. As described above, the greater the distance between the Si atom and the alicyclic epoxy group, that is, the larger the number of atoms constituting the main chain of the spacer organic group Y and the longer the chain length, the more the flexural resistance of the hard coat layer 3 tends to improve.

[0165] The total light transmittance of the hard coat film is preferably 80% or higher, more preferably 85% or higher, and even more preferably 88% or higher. The haze of the hard coat film is preferably 1.5% or lower, more preferably 0.9% or lower, even more preferably 0.7% or lower, and particularly preferably 0.5% or lower. The yellowness (YI) of the hard coat film is preferably 10 or lower, more preferably 8 or lower, even more preferably 5 or lower, even more preferably 4 or lower, and particularly preferably 3 or lower.

[0166] [Applications of hard coat films] The hard coat film may have various functional layers. Examples of functional layers include anti-reflective layers, anti-glare layers, anti-static layers, and transparent electrodes. In addition, a transparent adhesive layer may be attached to the non-hard coat layer surface of the transparent resin film 1. Furthermore, a transparent adhesive layer may be attached to the hard coat film.

[0167] Because the hard coat film described above has high hardness, it can be suitably used as a cover window material placed on the outermost surface of an image display device. The hard coat film also has excellent flexibility, making it suitable for use as a cover window for foldable displays, and it can be applied to foldable displays of the type that fold with the screen facing outwards. [Examples]

[0168] The present invention will be described in more detail below based on examples and comparative examples, but the present invention is not limited to the following examples.

[0169] [Synthesis of silane compounds] <Synthesis Example 1> (Synthesis of ester compounds) In a reaction vessel equipped with a thermometer, a stirrer, and a distillation column, 161 g (1.03 mol) of methyl 3,4-epoxycyclohexane-1-carboxylate, 83.8 g (1.44 mol) of 2-propen-1-ol, and 936 mg (3.76 mmol) of dibutyltin oxide were charged and mixed uniformly. The mixture was then heated to 140°C and stirred for 6 hours while distilling off methanol produced by the reaction by flowing nitrogen to carry out the transesterification reaction. After the reaction was complete, defloration was performed under reduced pressure using a rotary evaporator, and the target product was isolated by distillation to obtain 135 g of "Reactant 1" (yield 72%).

[0170] (Synthesis of silane compounds) In a reaction vessel equipped with a thermometer, stirrer, and reflux condenser, 17.7 g (145 mmol) of trimethoxysilane and 8.85 g of toluene were charged and uniformly stirred at 80°C. To this mixture, a mixed solution of reactant 1:22 g (121 mmol), platinum catalyst solution (xylene solution of 1,3-divinyl-1,1,3,3,-tetramethyldisiloxane platinum complex, "PtVTS" manufactured by Yumicore Precious Metals Japan, platinum content 3.0 wt%):4.53 μL, and toluene:11 g was slowly added dropwise and stirred until homogeneous. The reaction was then carried out for 10 hours with heating and stirring at 80°C. After the reaction was complete, defloration was performed under reduced pressure using a rotary evaporator, and the target product was isolated by distillation to obtain 41.2 g of "silane compound 1" (yield 66%).

[0171] <Synthesis Example 2> (Synthesis of ester compounds) In a reaction vessel equipped with a thermometer, stirrer, and reflux condenser, 78.1 g (500 mmol) of methyl 3,4-epoxycyclohexane-1-carboxylate, 45.1 g (625 mmol) of 3-buten-1-ol, and 227 mg (0.913 mmol) of dibutyltin oxide were charged and mixed uniformly. The mixture was heated to 140°C and stirred for 6 hours while flowing nitrogen to carry out the transesterification reaction. After the reaction was complete, defloration was performed under reduced pressure using a rotary evaporator to obtain 69.8 g of "Reactant 2" (yield 71%).

[0172] (Synthesis of silane compounds) In a reaction vessel equipped with a thermometer, stirrer, and reflux condenser, 52.2 g (427 mmol) of trimethoxysilane and 26.1 g of toluene were charged and heated to 80°C, stirring thoroughly. To this mixture, a mixed solution of 69.8 g (356 mmol) of reactant 2, 13.4 μL of platinum catalyst solution, and 34.9 g of toluene was slowly added dropwise and stirred until homogeneous. The reaction was then carried out at 80°C with heating and stirring for 10 hours. After the reaction was complete, defloration was performed under reduced pressure using a rotary evaporator to obtain 95.5 g of "silane compound 2" (yield 84%).

[0173] <Synthesis Example 3> (Synthesis of ester compounds) In a reaction vessel equipped with a thermometer, stirrer, and reflux condenser, 72.5 g (464 mmol) of methyl 3,4-epoxycyclohexane-1-carboxylate, 50 g (581 mmol) of 4-penten-1-ol, and 211 mg (0.848 mmol) of dibutyltin oxide were charged and mixed uniformly. The mixture was heated to 140°C and stirred for 6 hours while flowing nitrogen to carry out the transesterification reaction. After the reaction was complete, defloration was performed under reduced pressure using a rotary evaporator to obtain 83.2 g of "Reactant 3" (yield 85%).

[0174] (Synthesis of silane compounds) In a reaction vessel equipped with a thermometer, stirrer, and reflux condenser, 54.5 g (446 mmol) of trimethoxysilane and 27.3 g of toluene were charged and uniformly stirred at 80°C. To this mixture, a mixed solution of 78.2 g (372 mmol) of reactant 3, 14.0 μL of platinum catalyst solution, and 39.1 g of toluene was slowly added dropwise and stirred until homogeneous. The reaction was then carried out for 10 hours with heating and stirring at 80°C. After the reaction was complete, defloration was performed under reduced pressure using a rotary evaporator to obtain 85 g of "silane compound 3" (yield 69%).

[0175] <Synthesis Example 4> (Synthesis of ester compounds) In a reaction vessel equipped with a thermometer, a stirrer, and a reflux condenser, 62.4 g (399 mmol) of methyl 3,4-epoxycyclohexane-1-carboxylate, 50 g (499 mmol) of 5-hexen-1-ol, and 181 mg (0.729 mmol) of dibutyltin oxide were charged and mixed uniformly. The mixture was heated to 140°C and stirred for 6 hours while flowing nitrogen to carry out the transesterification reaction. After the reaction was complete, defloration was performed under reduced pressure using a rotary evaporator to obtain 50.0 g of "Reactant 4" (yield 56%).

[0176] (Synthesis of silane compounds) In a reaction vessel equipped with a thermometer, stirrer, and reflux condenser, 32.6 g (266 mmol) of trimethoxysilane and 16.3 g of toluene were charged and heated to 80°C, stirring thoroughly. To this mixture, a mixed solution of 49.8 g (222 mmol) of reactant 4, 8.34 μL of platinum catalyst solution, and 24.9 g of toluene was slowly added dropwise and stirred until homogeneous. The reaction was then carried out at 80°C with heating and stirring for 10 hours. After the reaction was complete, defloration was performed under reduced pressure using a rotary evaporator to obtain 55.2 g of "silane compound 4" (yield 72%).

[0177] <Synthesis Example 5> (Synthesis of ester compounds) In a reaction vessel equipped with a thermometer, stirrer, and reflux condenser, 125 g (800 mmol) of methyl 3,4-epoxycyclohexane-1-carboxylate, 128 g (1 mol) of 7-octen-1-ol, and 2.91 g (11.7 mmol) of dibutyltin oxide were charged and mixed uniformly. The mixture was heated to 140°C and stirred for 6 hours while flowing nitrogen to carry out the transesterification reaction. After the reaction was complete, defloration was performed under reduced pressure using a rotary evaporator to obtain 174 g of "Reactant 5" (yield 86%).

[0178] (Synthesis of silane compounds) In a reaction vessel equipped with a thermometer, stirrer, and reflux condenser, 11.6 g (94.6 mmol) of trimethoxysilane and 5.79 g of toluene were charged and uniformly stirred at 80°C. To this mixture, a mixed solution of reactant 5: 20 g (78.9 mmol), platinum catalyst solution: 2.96 μL, and toluene: 10 g was slowly added dropwise and stirred until homogeneous. The reaction was then carried out for 10 hours with heating and stirring at 80°C. After the reaction was complete, defloration was performed under reduced pressure using a rotary evaporator to obtain 15.7 g of "silane compound 5" (yield 53%).

[0179] <Synthesis Example 6> (Synthesis of silane compounds) In a reaction vessel equipped with a thermometer, stirrer, and reflux condenser, 42.1 g (257 mmol) of triethoxysilane and 30 g of toluene were charged and mixed uniformly, then stirred at 105°C. To this mixture, a mixed solution of 50 g (197 mmol) of reactant 5, 7.41 μL of platinum catalyst solution, and 21.1 g of toluene was slowly added dropwise and stirred until homogeneous. The reaction was then carried out for 10 hours with heating and stirring at 80°C. After the reaction was complete, defloration was performed under reduced pressure using a rotary evaporator to obtain 59.1 g of "silane compound 6" (yield 72%).

[0180] <Synthesis Example 7> (Synthesis of ester compounds) In a reaction vessel equipped with a thermometer, stirrer, and reflux condenser, 125 g (800 mmol) of methyl 3,4-epoxycyclohexane-1-carboxylate, 88.1 g (1 mol) of ethylene glycol monovinyl ether, and 2.91 g (11.7 mmol) of dibutyltin oxide were charged and mixed uniformly. The mixture was heated to 140°C and stirred for 6 hours while flowing nitrogen to carry out the transesterification reaction. After the reaction was complete, defloration was performed under reduced pressure using a rotary evaporator to obtain 109.6 g of "Reactant 6" (yield 65%).

[0181] (Synthesis of silane compounds) In a reaction vessel equipped with a thermometer, stirrer, and reflux condenser, 50.3 g (306 mmol) of triethoxysilane and 30 g of toluene were charged and uniformly stirred at 105°C. To this mixture, a mixed solution of 50 g (236 mmol) of reactant 6, 200 μL of platinum catalyst solution, and 30 g of toluene was slowly added dropwise and stirred until homogeneous. The reaction was then carried out for 10 hours with heating and stirring at 80°C. After the reaction was complete, the catalyst was removed with activated carbon, and defloration was performed under reduced pressure using a rotary evaporator to obtain 72.3 g of "silane compound 7" (yield 82%).

[0182] <Synthesis Example 8> (Synthesis of ester compounds) In a reaction vessel equipped with a thermometer, stirrer, and reflux condenser, 94.0 g (600 mmol) of methyl 3,4-epoxycyclohexane-1-carboxylate, 87.8 g (750 mmol) of 4-hydroxybutyl vinyl ether, and 2.18 g (8.76 mmol) of dibutyltin oxide were charged and mixed uniformly. The mixture was heated to 140°C and stirred for 6 hours while flowing nitrogen to carry out the transesterification reaction. After the reaction was complete, defloration was performed under reduced pressure using a rotary evaporator to obtain 111 g of "Reactant 7" (yield 77%).

[0183] (Synthesis of silane compounds) In a reaction vessel equipped with a thermometer, stirrer, and reflux condenser, 16.5 g (101 mmol) of triethoxysilane and 16.5 g of toluene were charged and uniformly stirred at 80°C. To this mixture, a mixed solution of 18.6 g (77.4 mmol) of reactant 7, 46.5 μL of platinum catalyst solution, and 18.6 g of toluene was slowly added dropwise and stirred until homogeneous. The reaction was then carried out at 105°C with heating and stirring for 10 hours. After the reaction was complete, the catalyst was removed with activated carbon, and defloration was performed under reduced pressure using a rotary evaporator to obtain 30 g of "silane compound 8" (yield 96%).

[0184] [Evaluation of silane compounds] <Moist heat test of methoxysilane compounds> The silane compounds of Synthesis Examples 1-5 were left for 20 hours at 85°C and 85% relative humidity, and then analyzed using a Bruker 400 MHz NMR spectrum with deuterated acetone as the solvent. 1 1H-NMR measurements were performed to calculate the proportion of unreacted methoxy groups. For reference, a similar evaluation was also performed on 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (Shin-Etsu Chemical Co., Ltd. "KBM-303").

[0185] <Heat-induced heat test of ethoxysilane compounds> After leaving the silane compounds of synthesis examples 6-8 in an environment of 85°C and 85% relative humidity for 96 hours, 1 The proportion of unreacted ethoxy groups was calculated by 1H-NMR. For reference, a similar evaluation was performed on 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane (Tokyo Chemical Industries, Ltd., "T3585").

[0186] Table 1 shows the results of the moist heat test (residual rate of methoxy group) for methoxysilane compounds, and Table 2 shows the results of the moist heat test (residual rate of ethoxy group) for ethoxysilane compounds.

[0187] [Table 1]

[0188] [Table 2]

[0189] In Table 1, KBM-303, a silane compound in which a 3,4-epoxycyclohexyl group and a Si atom are bonded via an ethylene group (with 2 atoms in the main chain), had a methoxy group retention rate of 25%. In contrast, silane compounds 1-5, in which a 3,4-epoxycyclohexyl group and a Si atom are bonded via a divalent organic group containing an ester bond (with 5-10 atoms in the main chain), had a methoxy group retention rate of 50% or more, demonstrating excellent resistance to heat and humidity (storage stability).

[0190] In silane compounds 1-5, a tendency was observed where the higher the number of atoms in the main chain of the divalent organic group between the 3,4-epoxycyclohexyl group and the Si atom, the higher the retention rate of the methoxy group (improved resistance to moisture and heat). Silane compounds 3-5 had a retention rate of over 80% of the methoxy group.

[0191] In Table 2, silane compound T3585, in which a 3,4-epoxycyclohexyl group and a Si atom are bonded via an ethylene group (with 2 atoms in the main chain), had a residual ethoxy group of 34%. In contrast, silane compounds 6-8, in which a 3,4-epoxycyclohexyl group and a Si atom are bonded via a divalent organic group containing an ester bond and with 5 or more atoms in the main chain, had a residual ethoxy group of 50% or more, demonstrating excellent resistance to heat and humidity (storage stability).

[0192] From these results, it can be seen that in both trimethoxysilane and triethoxysilane, silane compounds in which the 3,4-epoxycyclohexyl group and Si atom are bonded via a divalent organic group with 5 or more atoms in the main chain exhibit suppressed hydrolysis of the alkoxysilyl group in high-temperature and high-humidity environments, and thus demonstrate excellent storage stability.

[0193] [Synthesis of polyorganosiloxane compounds] <Synthesis Example 9> In a reaction vessel equipped with a thermometer, a stirrer, and a reflux condenser, 8.00 g (26.3 mmol) of silane compound 1 obtained in Synthesis Example 1, 2.37 g of propylene glycol monomethyl ether, and 0.59 g of methanol were charged and mixed uniformly. To this mixture, a solution of 1.25 mg (0.013 mmol) of magnesium chloride as a catalyst dissolved in 1.42 g (78.9 mmol) of water was slowly added dropwise, and the mixture was mixed until homogeneous. The temperature was then raised to 80°C, and the polycondensation reaction was carried out for 6 hours with stirring. After the reaction was complete, the solvent and water were removed by distillation using a rotary evaporator to obtain 6.2 g of "polyorganosiloxane compound 1" (yield 100%).

[0194] Measurements were taken using a Bruker 400 MHz NMR spectrum with deuterated acetone as the solvent. 1 The residual rate of methoxy groups, calculated from the 1H-NMR spectrum, was 6.7%, and the residual rate of epoxy groups was 98%.

[0195] <Synthesis Example 10> In a reaction vessel equipped with a thermometer, a stirrer, and a reflux condenser, 9.56 g (30 mmol) of silane compound 2 obtained in Synthesis Example 2, 2.70 g of propylene glycol monomethyl ether, and 0.673 g of methanol were charged and mixed uniformly. To this mixture, a solution of 1.43 mg (0.14 mmol) of magnesium chloride dissolved in 1.62 g (90 mmol) of water was slowly added dropwise, and the mixture was mixed until homogeneous. The temperature was then raised to 80°C, and the polycondensation reaction was carried out for 6 hours with stirring. After the reaction was complete, the solvent and water were removed by distillation using a rotary evaporator to obtain 7.3 g of "polyorganosiloxane compound 2" (yield 98%). The remaining methoxy group percentage of polyorganosiloxane compound 2 was 3.2%, and the remaining epoxy group percentage was 100%.

[0196] <Synthesis Example 11> The reaction was carried out in the same manner as in Synthesis Example 10, except that silane compound 3 obtained in Synthesis Example 3: 9.97 g (30 mmol) was used instead of silane compound 2, yielding 7.8 g of "polyorganosiloxane compound 3" (yield 98%). The residual rates of polyorganosiloxane compound 3 were 4.3% for methoxy groups and 98% for epoxy groups.

[0197] <Synthesis Example 12> The reaction was carried out in the same manner as in Synthesis Example 10, except that 10.4 g (30 mmol) of silane compound 4 obtained in Synthesis Example 4 was used instead of silane compound 2, yielding 8.0 g of "polyorganosiloxane compound 4" (yield 96%). The remaining methoxy group percentage of polyorganosiloxane compound 4 was 4.7%, and the remaining epoxy group percentage was 94%.

[0198] <Synthesis Example 13> In a reaction vessel equipped with a thermometer, a stirrer, and a reflux condenser, 9.87 g (26.3 mmol) of silane compound 5 obtained in Synthesis Example 5, 2.37 g of propylene glycol monomethyl ether, and 0.590 g of methanol were charged and mixed uniformly. To this mixture, a solution of 1.25 mg (0.013 mmol) of magnesium chloride dissolved in 1.42 g (78.9 mmol) of water was slowly added dropwise, and the mixture was mixed until homogeneous. The temperature was then raised to 80°C, and the polycondensation reaction was carried out for 6 hours with stirring. After the reaction was complete, the solvent and water were removed using a rotary evaporator to obtain 7.4 g of "polyorganosiloxane compound 5" (yield 92%). The remaining methoxy group percentage of polyorganosiloxane compound 5 was 4.1%, and the remaining epoxy group percentage was 91%.

[0199] <Synthesis Example 14> In a reaction vessel equipped with a thermometer, a stirrer, and a reflux condenser, 8.52 g (28 mmol) of silane compound 1 obtained in Synthesis Example 1, 2.15 g (7 mmol) of 8-glycidoxyoctyltrimethoxysilane (KBM-4803, manufactured by Shin-Etsu Chemical Co., Ltd.), 3.15 g of propylene glycol monomethyl ether, and 0.785 g of methanol were charged and mixed uniformly. To this mixture, a solution of 1.25 mg (0.013 mmol) of magnesium chloride dissolved in 1.42 g (78.9 mmol) of water was slowly added dropwise, and the mixture was mixed until homogeneous. The temperature was then raised to 80°C, and the polycondensation reaction was carried out for 6 hours with stirring. After the reaction was complete, the solvent and water were removed by distillation using a rotary evaporator to obtain 7.8 g of "polyorganosiloxane compound 6" (yield 94%). The remaining methoxy group percentage of polyorganosiloxane compound 6 was 6.7%, and the remaining epoxy group percentage was 97%.

[0200] <Synthesis Example 15> The reaction was carried out in the same manner as in Synthesis Example 14, except that the amount of silane compound 1 was changed to 7.46 g (24.5 mmol) and the amount of 8-glycidoxyoctyltrimethoxysilane was changed to 3.22 g (10.5 mmol), yielding 7.4 g of "polyorganosiloxane compound 7" (yield 90%). The remaining methoxy group percentage of polyorganosiloxane compound 7 was 9.2%, and the remaining epoxy group percentage was 94%.

[0201] <Synthesis Example 16> The reaction was carried out in the same manner as in Synthesis Example 14, except that the amount of silane compound 1 was changed to 6.39 g (21 mmol) and the amount of 8-glycidoxyoctyltrimethoxysilane was changed to 4.29 g (14 mmol), yielding 7.7 g of "polyorganosiloxane compound 8" (yield 93%). The residual rate of methoxy groups in polyorganosiloxane compound 8 was 11.5%, and the residual rate of epoxy groups was 89%.

[0202] <Synthesis Example 17> The reaction was carried out in the same manner as in Synthesis Example 14, except that the amount of silane compound 1 was changed to 5.33 g (17.5 mmol) and the amount of 8-glycidoxyoctyltrimethoxysilane was changed to 5.36 g (17.5 mmol), yielding 8.1 g of "polyorganosiloxane compound 9" (yield 98%). The residual rate of methoxy groups in polyorganosiloxane compound 9 was 7.2%, and the residual rate of epoxy groups was 93%.

[0203] <Synthesis Example 18> The reaction was carried out in the same manner as in Synthesis Example 14, except that the amount of silane compound 1 was changed to 4.26 g (14 mmol) and the amount of 8-glycidoxyoctyltrimethoxysilane was changed to 6.44 g (21 mmol), yielding 8.0 g of "polyorganosiloxane compound 10" (yield 96%). The remaining methoxy group percentage of polyorganosiloxane compound 10 was 6.6%, and the remaining epoxy group percentage was 96%.

[0204] <Synthesis Example 19> The reaction was carried out in the same manner as in Synthesis Example 14, except that the amount of silane compound 1 was changed to 3.20 g (10.5 mmol) and the amount of 8-glycidoxyoctyltrimethoxysilane was changed to 7.51 g (24.5 mmol), yielding 8.2 g of "polyorganosiloxane compound 11" (yield 97%). The residual rate of methoxy groups in polyorganosiloxane compound 11 was 8.1%, and the residual rate of epoxy groups was 97%.

[0205] <Synthesis Example 20> In a reaction vessel equipped with a thermometer, a stirrer, and a reflux condenser, 4.78 g (15 mmol) of silane compound 2 obtained in Synthesis Example 2, 4.60 g (15 mmol) of 8-glycidoxyoctyltrimethoxysilane, 2.70 g of propylene glycol monomethyl ether, and 0.673 g of methanol were charged and mixed uniformly. To this mixture, a solution of 1.43 mg (0.015 mmol) of magnesium chloride dissolved in 1.62 g (90 mmol) of water was slowly added dropwise, and the mixture was mixed until homogeneous. The temperature was then raised to 80°C, and the polycondensation reaction was carried out for 6 hours with stirring. After the reaction was complete, the solvent and water were removed by distillation using a rotary evaporator to obtain 7.2 g of "polyorganosiloxane compound 12" (yield 96%). The remaining methoxy group percentage of polyorganosiloxane compound 14 was 5.3%, and the remaining epoxy group percentage was 96%.

[0206] <Synthesis Example 21> The reaction was carried out in the same manner as in Synthesis Example 21, except that silane compound 3 obtained in Synthesis Example 3: 4.99 g (15 mmol) was used instead of silane compound 2, yielding 7.3 g of "polyorganosiloxane compound 13" (yield 92%). The remaining percentage of methoxy groups in polyorganosiloxane compound 13 was 4.3%, and the remaining percentage of epoxy groups was 98%. The remaining percentage of methoxy groups was 3.6%, and the remaining percentage of epoxy groups was 95%.

[0207] <Synthesis Example 22> In a reaction vessel equipped with a thermometer, a stirrer, and a reflux condenser, 61.6 g (250 mmol) of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane and 15.3 g of 1-methoxy-2-propanol were charged and mixed uniformly. To this mixture, a solution of 36 mg (0.375 mmol) of magnesium chloride dissolved in 9.0 g (499 mmol) of water was slowly added dropwise, and the mixture was mixed until uniform. The temperature was then raised to 80°C, and the polycondensation reaction was carried out for 6 hours with stirring. After the reaction was complete, the solvent and water were removed by distillation using a rotary evaporator to obtain "Polyorganosiloxane Compound 14". The remaining methoxy group percentage of Polyorganosiloxane Compound 14 was 4.6%, and the remaining epoxy group percentage was 95% or more.

[0208] <Synthesis Example 23> In a reaction vessel equipped with a thermometer, a stirrer, and a reflux condenser, 368 g (1.20 mol) of 8-glycidyloxyoctyltrimethoxysilane and 76.9 g of methanol were charged and mixed uniformly. To this mixture, a solution of 57 mg (0.6 mmol) of magnesium chloride dissolved in 64.7 g (3.60 mol) of water was slowly added dropwise and mixed until homogeneous. The temperature was then raised to 80°C, and the polycondensation reaction was carried out for 6 hours with stirring. After the reaction was complete, the solvent and water were removed using a rotary evaporator to obtain "Polyorganosiloxane Compound 15". The remaining methoxy group percentage of Polyorganosiloxane Compound 15 was 4.3%, and the remaining epoxy group percentage was 95% or more.

[0209] [Preparation of polyimide film] As diamines, 2,2'-bis(trifluoromethyl)benzidine (TFMB) and 3,3'-diaminodiphenylsulfone (3,3'-DDS) were dissolved in dimethylformamide (DMF) in a molar ratio of 90:10. As tetracarboxylic dianhydrides, bis(1,3-dihydro-1,3-dioxo-5-isobenzofurancarboxylic acid)-(2,2',3,3',5,5'-hexamethyl[1,1'-biphenyl]-4,4'-diyl) ester (TAHMBP), 1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA), and 4,4'-oxydiphthalic acid dianhydride (ODPA) were added in a molar ratio of 50:30:20. The mixture was stirred under a nitrogen atmosphere for 12 hours to obtain a polyamic acid solution with a solid content of 18%.

[0210] Pyridine and acetic anhydride were added to this polyamic acid solution, and imidization was carried out by stirring at 80°C for 4 hours. A mixture of 2-propyl alcohol (IPA) and DMF was added dropwise to this solution to precipitate polyimide resin, which was then filtered by suction, washed, and vacuum dried to obtain the polyimide resin.

[0211] 100 parts by weight of the above polyimide, 2 parts by weight of ADEKA's "ADEKA Stab LA-31RG" and 0.8 parts by weight of ADEKA's "ADEKA Stab LA-F70" as UV absorbers, and 0.006 parts by weight of Arimoto Chemical Industry's "Plast Blue 8590" as a bluing agent were dissolved in methylene chloride to obtain a polyimide solution with a solid content of 10% by weight. The polyimide solution was applied to an alkali-free glass plate using a bar coater, and the solvent was removed by heating in an air atmosphere at 40°C for 60 minutes, 80°C for 30 minutes, 150°C for 30 minutes, 170°C for 30 minutes, and 200°C for 60 minutes to obtain a polyimide film with a thickness of 50 μm.

[0212] [Production of hard coat film] <Example 1> (Preparation of hard coat composition) Polyorganosiloxane compound 1 was diluted to 50% with propylene glycol monomethyl ether. A hard coat composition was obtained by mixing 2 parts by weight (solid content) of a 50% propylene carbonate solution of a photocationic polymerization initiator (SunApro "CPI-101A") and 0.2 parts by weight (solid content) of a silicone leveling agent (BYK "BYK-300") with 100 parts by weight of the polyorganosiloxane compound.

[0213] (Formation of the hard coat layer) On one side of a 50μm thick transparent polyimide film, a discharge output of 600W·min / m was applied. 2 After corona treatment, the above hard coat composition was applied using a bar coater to a dry film thickness of 40 μm, and heated at 120°C for 10 minutes. Subsequently, a high-pressure mercury lamp was used to apply an integrated light intensity of 600 mJ / cm² at a wavelength of 365 nm. 2 The hard coat composition was cured by irradiating it with ultraviolet light in such a manner.

[0214] (Formation of the top coat layer) On the surface of the hard coat layer, discharge output of 3000W·min / m 2 After corona treatment, a solution of 3-(2-aminoethylamino)propyltrimethoxysilane (Tokyo Chemical Industries, Ltd. "A0774") diluted to 1% by weight with ethanol was applied to the surface of the hard coat layer using a bar coater to a dry film thickness of 35 nm, and the solvent was removed by heating to 130°C to form a primer layer. On the primer layer, a solution of a fluorine-based coating agent (Daikin Industries, Ltd. "OPTOOL UD509") diluted to 0.1% by weight with hydrofluoroether (3M Industries, Ltd. "NOVEC7200") was applied using a bar coater to a dry film thickness of 10 nm, and the top coat layer was formed by heating at 150°C for 10 minutes, thereby obtaining a hard coat film having a hard coat layer and a top coat layer on one side of a transparent polyimide film.

[0215] <Examples 2-14, Comparative Examples 1-3> In the preparation of the hard coat composition, polyorganosiloxane compounds 2 to 15 were used instead of polyorganosiloxane compound 1. In Examples 7 to 9, "CPI-310FG" manufactured by Sun Apro was used as the photo cationic polymerization initiator. In Example 6 and Comparative Example 2, the thickness of the hard coat layer was set to 20 μm. Except for these changes, a hard coat film having a hard coat layer, a primer layer, and a top coat layer was obtained on one surface of a transparent polyimide film in the same manner as in Example 1.

[0216] [Evaluation of Hard Coat Film] <Surface hardness (pencil hardness)> According to JIS K5600-5-4:1999, the pencil hardness of the hard coat layer formation surface (top coat layer surface) was measured with a load of 750 g.

[0217] <Flexural resistance (cylindrical mandrel diameter)> According to JIS K5600-5-1:1999, using a type 1 tester, a cylindrical mandrel test of the hard coat film was performed with the hard coat layer formation surface on the outside, and the minimum bending diameter φ (mandrel diameter of the test immediately before cracks occur) at which no cracks occur in the hard coat layer was determined.

[0218] <Flexural resistance (dynamic bending test)> The hard coat film was cut into strips with a width of 25 mm. The short side of this test piece was attached to a U-shaped expansion and contraction test jig (manufactured by Yuasa System Equipment), and in an environment of a temperature of 23°C and a relative humidity of 55%, a flat body unloaded U-shaped expansion and contraction test (DMLHB-FS-C manufactured by Yuasa System Equipment) was performed with a bending radius of 3.0 mm, a bending angle of 180°C, and a bending speed of 1 cycle / second, and a repeated bending test was performed with the hard coat layer formation surface on the outside. Based on the number of bending times (flexural resistance) until cracks occurred in the hard coat layer, the flexural resistance was evaluated according to the following criteria. A: The number of flexural resistance is 1.1 million times or more B: The number of flexural resistance is 500,000 times or more and less than 1.1 million times C: The number of flexural resistance is 370,000 times or more and less than 500,000 times D: The number of flexural resistance is 200,000 times or more and less than 370,000 times E: The number of bending resistance cycles is 150,000 or more and less than 200,000 F: The number of bending resistance cycles is 100,000 or more and less than 150,000 G: The number of bending resistance cycles is 10,000 or more and less than 100,000 H: The number of bending resistance cycles is 1,000 or more and less than 10,000 X: The number of bending resistance cycles is less than 1,000

[0219] <Curl> After the formation of the hard coat layer (curing of the hard coat composition), the hard coat film cured for 1 month at 25°C was cut out into a 3 cm square and placed on a horizontal table with the concave surface of the hard coat film facing up. The heights from the table to the four corners of the film were measured respectively, and the average value was taken as the curl amount. The curl amount when the hard coat layer forming surface was concave upward was taken as a positive value, and the curl amount when the hard coat layer forming surface was concave downward was taken as a negative value.

[0220] <Scratch resistance> Steel wool #s0000 was set on a pressure head with a diameter of 27 mm, and using a reciprocating wear tester (manufactured by Shin To Kagaku, TYPE: 30S), under the conditions of a load of 500 g, a stroke of 50 mm, 1 cycle / second, and 1500 cycles, a scratch resistance test (steel wool test) of the hard coat layer forming surface was performed. In any of the examples and comparative examples, no scratches were observed on the hard coat film after the test, indicating excellent scratch resistance.

[0221] <Total light transmittance and haze> It was measured by a haze meter "HZ-V3" manufactured by Suga Test Instruments according to the methods described in JIS K7361-1:1999 and JIS K7136:2000.

[0222] <Yellowness index (YI)> It was measured by a colorimeter "SC-P" manufactured by Suga Test Instruments according to the methods described in JIS K7373-:2006.

[0223] [Evaluation results] Table 3 shows the composition of the hard coat layer (molar ratio of silane compounds used in the synthesis of the polyorganosiloxane compounds), the thickness of the hard coat layer, and the evaluation results for the hard coat films of the examples and comparative examples. [Table 3]

[0224] Comparative Example 1, which used polyorganosiloxane compound 14 (see Synthesis Example 22) obtained by condensation of KBM-303, a silane compound in which a 3,4-epoxycyclohexyl group and a Si atom are bonded via an ethylene group (2 atoms in the main chain), as the curable resin component, had high surface hardness and small curl, but insufficient flexibility. Comparative Example 2, in which the thickness of the hard coat layer was reduced to 20 μm, showed similar results.

[0225] Comparative Example 3, which used polyorganosiloxane compound 15 (see Synthesis Example 23) obtained by condensation of KBM-4803, a silane compound having a glycidyloxy group, as the curable resin component, had excellent flexibility, but suffered from significant curling and poor handling properties.

[0226] The hard coat films of Examples 1 to 14 exhibited superior flexural resistance compared to Comparative Examples 1 and 2, and showed less curling compared to Comparative Example 3.

[0227] From these results, it can be seen that a hard coat film using a polyorganosiloxane compound having a spacer with a specific chain length between the Si atom and the alicyclic epoxy group as the curable resin component can achieve both scratch resistance and flexibility when the hard coat is bent outwards, and also exhibits minimal curling and excellent handling properties. [Explanation of symbols]

[0228] 1. Transparent resin film 3. Hard court layer 5. Top coat layer 11,13 Hard coat film

Claims

1. A polyorganosiloxane compound which is a condensate of a silane compound, The silane compound includes a silane compound represented by general formula (I) or general formula (II), Polyorganosiloxane compounds containing a structure represented by general formula (11): 【Chemistry 1】 【Chemistry 2】 In general formulas (I) and (II), R1 is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, R2 is a hydrogen atom or a monovalent hydrocarbon group selected from the group consisting of alkyl groups having 1 to 10 carbon atoms, aryl groups having 6 to 25 carbon atoms, and aralkyl groups having 7 to 12 carbon atoms, R4 and R5 are divalent organic groups having 4 to 14 atoms in the main chain, and x is 2 or 3. In general formula (11), Y is a divalent organic group represented as -O-(C=O)-R4- in which the oxygen atom of the ester is bonded to the alicyclic ring of 3,4-epoxycyclohexyl, or a divalent organic group represented as -(C=O)-O-R5- in which the carbon atom of the ester is bonded to the alicyclic ring of 3,4-epoxycyclohexyl, and R4 and R5 are the same as R4 in general formula (I) and R5 in general formula (II), respectively.

2. The polyorganosiloxane compound according to claim 1, wherein the ratio of the structure represented by general formula (11) to the total amount of Si atoms is 0.3 or more.

3. The polyorganosiloxane compound according to claim 1 or 2, wherein x in general formula (I) and general formula (II) is 3.

4. R in general formula (I) and general formula (II) １ The polyorganosiloxane compound according to claim 3, wherein the group is a methyl group, an ethyl group, or a propyl group.

5. A hard coat composition comprising the polyorganosiloxane compound according to claim 1 or 2, and a photocationic polymerization initiator.

6. A hard coat layer is provided on at least one surface of the transparent resin film. The hard coat layer comprises a hard coat film containing a cured polyorganosiloxane compound according to claim 1 or 2.

7. The hard coat film according to claim 6, further comprising a top coat layer containing a fluorine compound on the hard coat layer.

8. The hard coat film according to claim 6, wherein the transparent resin film comprises one or more resin materials selected from the group consisting of polyester, polycarbonate, polyamide, polyimide, cyclic polyolefin, acrylic resin, and cellulosic resin.

9. A method for producing a hard coat film, comprising applying the hard coat composition described in claim 5 onto a transparent resin film and curing it by irradiating it with active energy rays to form a hard coat layer.

10. A method for producing a hard coat film according to claim 9, comprising forming the hard coat layer, then applying a composition containing a compound having an alkoxysilyl group and a perfluoroalkyl group in its molecule onto the hard coat layer, and condensing the compound to form a top coat layer.

11. A display comprising an image display panel and the hard coat film described in claim 6.

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