JP2013049765A - Composition for adhesive member and the adhesive member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive member having excellent transparency, adhesion, adhesive reliability at high temperature and high humidity, reworkability, and flexibility, as well as excellent corrosion resistance because of containing substantially no acid group.SOLUTION: The composition for adhesive member (F) contains unsaturated polyurethane prepolymer (A), alicyclic compound (B), alkyl (meth)acrylate with a carbon number of 8-18 (C), alkoxy polyalkylene glycol (meth)acrylate (D), and a photopolymerization initiator (E).

Description

  The present invention relates to an adhesive member composition and an adhesive member obtained by polymerizing the adhesive member composition with active energy rays.

  2. Description of the Related Art In recent years, image display devices using liquid crystal modules such as television and personal computer monitors and touch panel displays of various information terminals represented by smartphones and tablet terminals have come to be widely used. In manufacturing these image display devices, it is necessary to bond a liquid crystal module, various optical members such as a polarizing plate and a retardation plate, an input device such as a touch panel module, and a protective member such as a cover lens. For this reason, various bonding methods have been developed. In recent years, a technique using a baseless transparent double-sided adhesive sheet (for example, see Patent Document 1), a curable adhesive, various modules and optical members. The entire surface bonding is becoming the mainstream, such as a technique of filling between layers and bonding by curing with light or heat (for example, see Patent Document 2).

  In particular, bonding with an adhesive member such as a transparent double-sided adhesive sheet without a substrate is widely used for touch panel displays, etc. With the spread of smartphones and tablet terminals, various functions other than adhesive strength are required. It is supposed to be.

  For example, when bonding with a double-sided adhesive sheet, there is a problem that defective products are likely to come out due to foam biting, mixing of foreign substances, misalignment of the bonding position, etc. Therefore, an expensive liquid crystal module or touch panel module is peeled off by peeling the defective adhesive sheet Reworkability is required in order to reuse. Also, since it is often used for mobile information terminals such as smartphones and tablet devices, it is resistant to dropping impacts, peeling of adhesive parts even in high-temperature and high-humidity environments, resistance to discoloration such as cloudiness of adhesive members, etc. Excellent adhesion reliability is required. Besides, corrosion resistance not to corrode transparent conductive film such as ITO film and ITO glass used for touch panel modules, stress relaxation to reduce screen distortion and improve image display, VOC and odor Therefore, there is a demand for suppressing the occurrence of this.

  In order to suppress the generation of VOC and odor, it is common to use a photosensitive resin that polymerizes a monomer mixture with active energy rays in a double-sided adhesive sheet. Further, in order to achieve both adhesion reliability and stress relaxation properties, it has been proposed to use a composition containing a monomer having a carboxyl group such as acrylic acid (see, for example, Patent Documents 3 and 4). There was a problem with corrosivity.

  On the other hand, in consideration of corrosion resistance, an adhesive member using a composition having substantially no acid value has been studied, and it has been proposed to use an aminosilane compound to achieve both adhesion reliability and stress relaxation properties ( For example, see Patent Document 5), there is a problem that the adhesive member is easily yellowed because an aminosilane compound is used. In addition, it has been proposed to provide adhesion reliability with a combination of urethane acrylate and a hydrophilic monomer (see Patent Document 6). However, if the glass transition point of the hydrophilic monomer is high, the adhesiveness is poor, and the glass transition point is low. If it is low, the adhesive member is inferior in reworkability, and it is difficult to achieve both adhesion and reworkability.

JP 2003-238915 A JP 2009-186963 A JP 2010-189545 A WO2011 / 010599 gazette JP 2011-74308 A JP 2011-63701 A

  In view of the above circumstances, the present invention provides an adhesive member that is excellent in transparency, adhesion, adhesion reliability at high temperature and high humidity, reworkability, flexibility, and substantially free of acid groups, and thus has good corrosion resistance. Doing this is a technical issue.

  The present inventor has developed an unsaturated polyurethane prepolymer, an alicyclic compound, a linear or branched alkyl (meth) acrylate having 8 to 18 carbon atoms, a (meth) acrylate having a hydroxyalkyl group or an alkylene glycol chain, photopolymerization initiation It has been found that the above-mentioned problems can be solved by forming an adhesive member obtained by polymerizing a composition containing an agent with active energy rays.

  Specifically, the present invention can be solved as follows.

That is, the present invention
(1) 10-50 mass% of the following unsaturated polyurethane prepolymer (A), 5-30 mass% of alicyclic compound (B) represented by the following general formula (1), and represented by the following general formula (2) 10 to 65% by mass of alkyl (meth) acrylate (C), 5 to 40% by mass of monomer (D) represented by the following general formula (3), 0.2 to 5.0% by mass of photopolymerization initiator (E) A composition for an adhesive member, comprising:
(A) an unsaturated polyurethane prepolymer comprising a hydrogenated polybutadiene structure ^{_{(B) CH 2 = C (}} R 1) -COO- (R 2 -O) n-R 3 (1)
R ¹ is H or CH ₃ , R ² is CH ₂ CH ₂ or CH ₂ CH (CH ₃ ), and R ³ is cycloalkyl, cycloalkenyl, bicycloalkyl, bicycloalkenyl, tricycloalkyl, tricycloalkenyl And n is 0 or 1.
^{_{(C) CH 2 = C (}} R 1) -COO-R 2 (2)
R ¹ is H or CH ₃ and R ² is a linear or branched alkyl having 8 to 18 carbon atoms.
^{_{(D) CH 2 = C (}} R 1) -COO- (R 2 -O) n-R 3 (3)
R ¹ is H or CH ₃ , R ² is alkylene having 2 to 4 carbon atoms, R ³ is H or alkyl having 1 to 4 carbon atoms, and n is 1 to 10.
(2) The hydrogenated polybutadiene structure of the unsaturated urethane prepolymer (A) is derived from a hydrogenated polybutadiene obtained by hydrogenating a polybutadiene having a 1,2-polybutadiene structure of 80% by mass or more ( 1) Composition for adhesive member,
(3) The composition for an adhesive member according to (1) or (2), wherein the alicyclic compound (B) is a methacrylic acid ester having a bicycloalkyl group and / or a tricycloalkyl group,
(4) The composition for an adhesive member according to any one of (1) to (3), wherein the acid value is 1 mgKOH / g or less,
(5) For a total of 100% by mass of unsaturated polyurethane prepolymer (A), alicyclic compound (B), alkyl (meth) acrylate (C), monomer (D), and photopolymerization initiator (E), The composition for adhesive members according to any one of (1) to (4), comprising 5.0% by mass or less of a silane coupling agent (G),
(6) For a total of 100% by mass of unsaturated polyurethane prepolymer (A), alicyclic compound (B), alkyl (meth) acrylate (C), monomer (D), and photopolymerization initiator (E), The composition for adhesive members according to any one of (1) to (5), comprising 100% by mass or less of a flexibility-imparting agent (H),
(7) An adhesive member having a Shore A hardness of 1 or more and 25 or less obtained by polymerizing the composition for an adhesive member according to any one of (1) to (6) with active energy rays,
(8) The adhesive member according to (7), wherein the adhesive member is a double-sided adhesive sheet,
It is.

  ADVANTAGE OF THE INVENTION According to this invention, it is excellent in transparency, adhesiveness, the adhesive reliability in high temperature, high humidity, rework property, and a softness | flexibility, and provides an adhesive member with favorable corrosion resistance since it does not contain an acid group substantially. I can do it.

  The configuration of the present invention will be described in more detail as follows.

  The unsaturated polyurethane prepolymer (A) that can be used in the present invention is an unsaturated polymer having a hydrogenated polybutadiene structure, a hydrogenated polybutadiene having a hydroxyl group (a1), and a polyisocyanate having two or more isocyanate groups (a2). It is an unsaturated polyurethane prepolymer obtained by reacting a functional group having active hydrogen with a compound (a3) having both ethylenically unsaturated bonds in the molecule. By introducing a hydrogenated polybutadiene structure into the unsaturated polyurethane prepolymer (A), an adhesive member with improved flexibility can be provided. In addition, since the unsaturated polyurethane prepolymer obtained has both a highly hydrophobic hydrogenated polybutadiene structure and a highly polar urethane bond, the alicyclic compound (B) is a straight chain or branched chain having 8 to 18 carbon atoms. A highly hydrophobic monomer such as alkyl (meth) acrylate (C) and a highly hydrophilic monomer (D) having a hydroxyalkyl group or an alkylene glycol chain are compatible with each other, and a functional group having active hydrogen. Since the compound (a3) having both an ethylenically unsaturated bond in the molecule is introduced as a polymerizable group, the copolymerizability is also improved. Therefore, it becomes a homogeneous and tough cured product, and an adhesive member with improved reworkability can be provided.

  As for the usage-amount of the unsaturated polyurethane prepolymer (A) in this invention, content in the composition for adhesive members (F) is 10 to 50 mass%. When the content is 10% by mass or more, the rework property of the adhesive member obtained by polymerizing the composition for adhesive member (F) with active energy rays is improved, which is preferable. Moreover, when it is 50 mass% or less, since the adhesiveness of an adhesive member becomes favorable, it is preferable. When the content is 15% by mass or more and 40% by mass or less, the adhesiveness is further improved, which is preferable.

The unsaturated polyurethane prepolymer (A) used in the present invention can be produced by a known method. For example, a prepolymer precursor having an isocyanate group at the polymer terminal is synthesized by reacting a hydrogenated polybutadiene (a1) having a hydroxyl group with a polyisocyanate (a2) at a reaction temperature of 20 to 80 ° C. It can be obtained by adding a compound (a3) having both a functional group having hydrogen and an ethylenically unsaturated bond in the molecule. The reaction can be completed by continuing the incubation until there is no trace of the NCO characteristic absorption band near 2230 cm ⁻¹ by IR measurement.

  A catalyst may be used in the reaction of the hydrogenated polybutadiene (a1) having a hydroxyl group, the polyisocyanate (a2), the functional group having active hydrogen, and the compound (a3) having both ethylenically unsaturated bonds in the molecule. good. Examples of such a catalyst include di-n-butyltin dilaurate, stannous octoate, triethylenediamine, diethylenediamine, triethylamine, naphthenic acid metal salt, octylic acid metal salt such as lead octylate, and the like. These catalysts may be used alone or in combination of two or more.

  At this time, the ratio of the hydrogenated polybutadiene (a1) having a hydroxyl group, the polyisocyanate (a2), the functional group having active hydrogen and the compound (a3) having both ethylenically unsaturated bonds in the molecule is not particularly limited. For example, the molar ratio (NCO group / OH group) of the isocyanate group (NCO group) of the polyisocyanate (a2) to the hydroxyl group (OH group) of the hydrogenated polybutadiene (a1) having a hydroxyl group is 1.05 to 2.00. The prepolymer precursor having an NCO group at the polymer terminal is synthesized by reacting in the range of ## STR3 ## and the hydroxyl group of the compound (a3) having both a functional group having active hydrogen and an ethylenically unsaturated bond in the molecule ( It is preferable to react so that (OH group) becomes equivalent to the polymer chain terminal NCO group of the prepolymer precursor. When the ratio of the hydrogenated polybutadiene (a1) having a hydroxyl group, the polyisocyanate (a2), the functional group having active hydrogen and the compound (a3) having both ethylenically unsaturated bonds in the molecule is outside the above range, ethylene Insufficient introduction of the unsaturated unsaturated bond may cause a decrease in physical properties such as adhesiveness, reworkability, and strength of the pressure-sensitive adhesive member, and a decrease in storage stability due to residual isocyanate groups.

  By using the hydrogenated polybutadiene (a1) having a hydroxyl group, it is possible to obtain an unsaturated polyurethane prepolymer (A) having a hydrogenated polybutadiene structure, and the resulting adhesive member has a low rubber hardness as a flexible composition. can get. The polybutadiene having a hydroxyl group is preferably hydrogenated because hydrogenation reduces the rubber hardness and improves adhesion and flexibility. Hydrogenated polybutadiene having a 1,2-polybutadiene structure of 80% by mass or more is preferable because of excellent adhesion.

  The polyisocyanate (a2) may be a compound having two or more isocyanate groups such as diisocyanate and triisocyanate. Examples of the diisocyanate include 2,6-tolylene diisocyanate, 2,4-tolylene diisocyanate, p-xylylene diisocyanate, m-xylylene diisocyanate, p-hydrogenated xylylene diisocyanate, m-hydrogenated xylylene diisocyanate, isophorone diisocyanate, 1,6-hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, 4,4 ′ -Diphenylmethane diisocyanate, naphthalene diisocyanate, p-phenylene diisocyanate and the like. Examples of the triisocyanate include a biuret form of tolylene diisocyanate and its isocyanurate form, a biuret form of isophorone diisocyanate, and its isocyanurate form, a biuret form of 1,6-hexamethylene diisocyanate, and its isocyanurate form. Etc. Among them, diisocyanate is preferable since the production of the unsaturated polyurethane prepolymer (A) is easy. Furthermore, isophorone diisocyanate and 1,6-hexamethylene diisocyanate which are non-yellowing types are preferred.

  The compound (a3) having both a functional group having active hydrogen and an ethylenically unsaturated bond in the molecule may be any compound having both a functional group having active hydrogen and an ethylenically unsaturated bond in the molecule, Preferably, it is a compound having both a hydroxy group and an ethylenically unsaturated bond in the molecule. For example, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, polyethylene glycol mono (meth) acrylate , Polypropylene glycol mono (meth) acrylate, glycerin mono or di (meth) acrylate, and the like.

  The number average molecular weight of the unsaturated polyurethane prepolymer (A) is preferably 10,000 or more and 50,000 or less. When it becomes less than 10,000, the rubber hardness of the obtained adhesive member becomes high and the flexibility becomes poor. Therefore, in order to obtain a flexible adhesive member, the number average molecular weight is preferably 10,000 or more. When the number average molecular weight exceeds 50,000, the compatibility with the monomers becomes poor, and it becomes difficult to obtain a uniform composition (F) for an adhesive member. Therefore, the unsaturated polyurethane has a good compatibility with the monomers. For the prepolymer (A), the number average molecular weight is preferably 50,000 or less. Since the adhesiveness, flexibility, and compatibility become better, the number average molecular weight of the prepolymer is more preferably in the range of 15,000 to 30,000. The number average molecular weight here is an average molecular weight in terms of polystyrene using the GPC method.

By using the alicyclic compound (B) represented by the following general formula (1) in the present invention, sufficient adhesiveness can be expressed in the obtained adhesive member.
^{_{(B) CH 2 = C (}} R 1) -COO- (R 2 -O) n-R 3 (1)
R ¹ is H or CH ₃ , R ² is CH ₂ CH ₂ or CH ₂ CH (CH ₃ ), and R ³ is cycloalkyl, cycloalkenyl, bicycloalkyl, bicycloalkenyl, tricycloalkyl, tricycloalkenyl And n is 0 or 1.

Examples of the alicyclic compound (B) represented by the general formula (1) include cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, mono- or di- or trialkylcyclohexyl (meth) acrylate, and cyclohexyloxyethyl (meth) acrylate. , Monomers having a cycloalkyl group such as cycloheptyl (meth) acrylate, cyclohexenyl (meth) acrylate, mono- or di- or trialkylcyclohexenyl (meth) acrylate, cycloheptenyl (meth) acrylate, cyclohexenyloxyethyl (meth) Monomers having a cycloalkenyl group such as acrylate, cycloheptenyloxyethyl (meth) acrylate, [(1S, 4S) -1,7,7-trimethyl-6-bicyclo [2.2.1] heptani ] Monomers having a bicycloalkyl group such as (meth) acrylate, and bicycloalkenyl such as [(1S, 4S) -1,7,7-trimethyl-6-bicyclo [2.2.1] heptenyl] (meth) acrylate Group-containing monomers, (meth) acrylic acid tricyclo [5.2.1.0 (2,6)] decan-8-yl, (meth) acrylic acid (ethyloxy) tricyclo [5.2.1.0 ( 2,6)] decan-8-yl, (meth) acrylic acid 2-methyltricyclo [3.3.1.1 (3,7)] decan-2-yl, (meth) acrylic acid 2-ethyltri Cyclo [3.3.1.1 (3,7)] Monomers having a tricycloalkyl group such as decan-2-yl, 2- (3a, 4,5,6,7,7a), (meth) acrylic acid -Hexahydro-4,7-methano- 1H-inden-6-yl) ester, (meth) acrylic acid 2-[(3a, 4,5,6,7,7a-hexahydro-4,7-methano-1H-inden-6-yl) oxy] ethyl It is at least one compound selected from monomers having a tricycloalkenyl group such as an ester. Among them, particularly, from the viewpoint of adhesiveness of the adhesive member, R ³ of the alicyclic compound (B) represented by the general formula (1) is cycloalkyl, cycloalkenyl, bicycloalkyl having 6 to 12 carbon atoms, It is preferably an alkyl or alkenyl represented by bicycloalkenyl, tricycloalkyl or tricycloalkenyl, more preferably a methacrylate ester having a bicycloalkyl group, or a methacrylate ester having a tricycloalkyl group, specifically [(1S, 4S) -1,7,7-trimethyl-6-bicyclo [2.2.1] heptanyl] methacrylate, tricyclomethacrylate [5.2.1.0 (2,6)] decane-8 -Ile is preferred.

  As for the usage-amount of the alicyclic compound (B) in this invention, content in the composition for adhesive members (F) is 5 to 30 mass%. When the content is 5% by mass or more, the adhesiveness of the adhesive member obtained by polymerizing the composition for adhesive member (F) with active energy rays is preferable. Moreover, when it is 30 mass% or less, since rubber hardness becomes low and a softness | flexibility becomes favorable and rework property improves, it is preferable. When the content is 10% by mass or more and 25% by mass or less, the adhesiveness is further improved, which is preferable.

By using the alkyl (meth) acrylate represented by the following general formula (2) in the present invention, both the adhesiveness and flexibility of the adhesive member can be achieved.
^{_{(C) CH 2 = C (}} R 1) -COO-R 2 (2)
R ¹ is H or CH ₃ and R ² is a linear or branched alkyl having 8 to 18 carbon atoms.

  The alkyl (meth) acrylate (C) represented by the general formula (2) is a linear or branched alkylalkyl (meth) acrylate having 8 to 18 carbon atoms, specifically, (meth) acrylic acid 2 -Ethylhexyl, n-octyl (meth) acrylate, n-decyl (meth) acrylate, n-dodecyl (meth) acrylate, n-tridecyl (meth) acrylate, n-octadecyl (meth) acrylate, etc. Is at least one compound selected from the group consisting of

  As for the usage-amount of the alkyl (meth) acrylate (C) in this invention, content in the composition for adhesive members (F) is 10 mass% or more and 65 mass% or less. When the content is 10% by mass or more, the compatibility between the components of the adhesive member composition (F) is improved, and the adhesive obtained by polymerizing the adhesive member composition (F) with active energy rays. This is preferable because the transparency of the member increases. Moreover, when it is 65 mass% or less, since the adhesiveness of an adhesive member becomes favorable, it is preferable. When the content is 25% by mass or more and 50% by mass or less, the adhesiveness is further improved, which is preferable.

By using the monomer (D) represented by the following general formula (3) in the present invention, both adhesion and adhesion reliability at high temperature and high humidity can be achieved.
^{_{(D) CH 2 = C (}} R 1) -COO- (R 2 -O) n-R 3 (3)
R ¹ is H or CH ₃ , R ² is alkylene having 2 to 4 carbon atoms, R ³ is H or alkyl having 1 to 4 carbon atoms, and n is 1 to 10.

  As the monomer (D) represented by the general formula (3), a hydroxyalkyl (meth) acrylate having 2 to 4 carbon atoms in the alkyl group, 2 to 4 carbon atoms in the alkylene glycol, and 1 repeating unit of the alkylene glycol. 10 to 10 polyalkylene glycol (meth) acrylate, alkoxy polyalkylene glycol having 2 to 4 carbon atoms of alkoxy group, 2 to 4 carbon atoms of alkylene glycol, and 1 to 10 repeating units of alkylene glycol ( It is at least one compound selected from (meth) acrylate. Among them, 4-hydroxybutyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2-butoxydiethylene glycol (meta) particularly from the viewpoint of flexibility and adhesiveness of the adhesive member. ) Acrylate and propylene glycol (meth) acrylate are preferred.

  As for the usage-amount of the monomer (D) in this invention, content in the composition for adhesive members (F) is 5 to 40 mass%. When the content is 5% by mass or more, the adhesiveness and the adhesive reliability at high temperature and high humidity become favorable. Moreover, when it is 40 mass% or less, the compatibility of the composition for adhesive members (F) becomes favorable, and the adhesive member obtained by polymerizing the composition for adhesive members (F) with active energy rays is transparent. This is preferable because of increased properties. When the content is 15% by mass or more and 30% by mass or less, the adhesiveness is further improved, which is preferable.

  The photopolymerization initiator (E) in the present invention is not particularly limited as long as it is a polymerization initiator by light. Examples of the acetophenones include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropane. -1-one, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 4- (2-hydroxyethoxy) -phenyl- (2-hydroxy-2-propyl) ketone, 1 -Hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1, and benzoins include benzoin, α-methylbenzoin, α-phenylbenzoin, α-allylbenzoin, α-benzoylbenzoin, benzoin methyl ether, benzoin ethyl ether, As benzoin isopropyl ether, benzoin isobutyl ether, benzyl dimethyl ketal, and benzophenones, benzophenone, benzoyl benzoic acid, methyl benzoyl benzoate, and α-amino ketones as 2-methyl-1- [4- (methylthio) phenyl] 2- (4-morpholinyl) -1-propanone, 2-benzyl-2- (dimethylamino) -1- [4- (4-morpholinyl) phenyl] -1-butanone, xanthones include xanthone, thioxanthone, As anthraquinones, anthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, and as a polymer photoinitiator, {2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propane-1 -On} polymer, etc. . Two or more of these photopolymerization initiators may be used.

  The content of the photopolymerization initiator (E) in the composition for adhesive member (F) is 0.2% by mass or more and 5% by mass or less. When the content is 0.2% by mass or more, when the pressure-sensitive adhesive member is produced by photopolymerization, the amount of residual monomer in the adhesive member is reduced, and the adhesiveness and reworkability are improved. When the amount is 5% by mass or less, the pot life becomes long, and the problem of gelation during storage is reduced, and the molecular weight when the adhesive member composition (F) is photopolymerized increases. However, it is preferable because the adhesiveness and reworkability of the adhesive member are increased. In the case of 0.5% by mass or more and 3% by mass or less, the adhesion is further improved, which is preferable.

  In the composition for an adhesive member (F) in the present invention, a silane coupling agent (G) can also be used as a component used for the preparation of the composition for an adhesive member (F) of the present invention. The silane coupling agent (G) means a silane compound having a so-called coupling action, and specific examples include vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacrylic. Roxypropyltriethoxysilane, γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, n-propyltriethoxysilane and n-octyl Examples include alkylalkoxysilanes such as triethoxysilane and polyether-modified alkoxysilanes. In particular, from the point of affinity with each of the above components, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, And nonionic silane coupling agents such as polyether-modified alkoxysilanes are preferred. The silane coupling agent can be used within a range that is transparently dissolved in the adhesive member composition (F), and is an unsaturated polyurethane prepolymer (A), an alicyclic compound (B), an alkyl (meth) acrylate. The range of 5.0% by mass or less (more than 0% by mass and 5.0% by mass or less) is preferable with respect to the total of 100% by mass of (C), monomer (D), and photopolymerization initiator (E).

  The composition for an adhesive member (F) in the present invention can further use a flexibility-imparting agent (H) as a component used for the preparation of the composition for an adhesive member (F) of the present invention. Examples of the flexibility-imparting agent (H) include polybutadiene, hydrogenated polybutadiene, terpene resins, hydrocarbon-modified terpene resins, terpene resins such as hydrogenated products thereof, terpene phenol resins, hydrogenated products of terpene phenol resins, and the like. Terpene phenol resins, aliphatic petroleum resins, alicyclic petroleum resins, aromatic petroleum resins, copolymer petroleum resins, dicyclopentadiene petroleum resins, pure monomer petroleum resins, hydrogenated products thereof, etc. Petroleum resins, gum rosin, tall rosin, wood rosin, disproportionated rosin, polymerized rosin, glycerin ester and pentaerythritol ester of these rosins, rosin resins such as hydrogenated products, styrene resins, coumarone indene resins, Alkylphenol resin, xylene resin, dammar, co Pal, and the like shellac and the like. In particular, from the viewpoint of imparting affinity and flexibility with each of the above components, polybutadiene is preferred when the flexibility imparting agent (H) is used as necessary. The addition amount of the flexibility-imparting agent can be used within a range that is transparently dissolved in the adhesive member composition (F), and includes an unsaturated polyurethane prepolymer (A), an alicyclic compound (B), an alkyl ( The range of 100% by mass or less (more than 0% by mass and 100% by mass or less) is maintained with respect to 100% by mass of the total of (meth) acrylate (C), monomer (D), and photopolymerization initiator (E). However, it is preferable for imparting flexibility, and when used for imparting flexibility, adhesiveness, reworkability and the like can be maintained within a range of 100% by mass or less.

  The composition for an adhesive member (F) in the present invention further includes the alicyclic compound (B) and the alkyl (meth) acrylate (C) as components used for the preparation of the composition for an adhesive member (F) of the present invention. ) And the ethylenically unsaturated compound (I) other than the monomer (D) can be used in place of a part of the alkyl (meth) acrylate (C). Examples of the ethylenically unsaturated compound include linear or branched alkyl (meth) acrylate having 1 to 7 carbon atoms, halogenated alkyl (meth) acrylate, aminoalkyl (meth) acrylate, and tetrahydrofurfuryl (meth). Acrylate, allyl (meth) acrylate, glycidyl (meth) acrylate, benzyl (meth) acrylate, phenoxy (meth) acrylate, N-substituted or N, N′-substituted (meth) acrylamide, diacetone (meth) acrylamide, N, Di (meth) acrylates such as N′-alkylene bis (meth) acrylamide, alkylene glycol di (meth) acrylate, polyalkylene glycol di (meth) acrylate and polyalkylene oxide modified bisphenol A di (meth) acrylate , Trimethylolpropane tri (meth) acrylate, trimethylolpropane alkoxy tri (meth) acrylate, glycerin tri (meth) acrylate, glycerin alkoxy tri (meth) acrylate, pentaerythritol tri (meth) acrylate and pentaerythritol tetra (meth) acrylate And polyfunctional (meth) acrylates such as dipentaerythritol penta (meth) acrylate and dipentaerythritol hexa (meth) acrylate. These ethylenically unsaturated compounds may be used alone or in combination of two or more. The addition amount of these ethylenically unsaturated compounds is not particularly limited as long as it does not adversely affect the characteristics exhibited by the adhesive member according to the present invention, and is 5% by mass or less based on the adhesive member composition (F). A range is preferred.

  Further, the adhesive member composition (F) in the present invention may be mixed with other urethane acrylic oligomers, polyurethane resins, polyester resins, polyamide resins, polyimide resins, polyvinyl acetate, epoxy resins, various additives, etc. as necessary. Can be used. Additives include thermal polymerization inhibitors, antioxidants, antioxidants, phosphate esters and other flame retardants, antistatic agents such as surfactants, colorants, plasticizers, surface lubricants, leveling agents And softeners. The addition amount of these various resins and additives is not particularly limited as long as it does not adversely affect the characteristics exhibited by the adhesive member according to the present invention, and is 5% by mass or less with respect to the adhesive member composition (F). A range is preferred.

  Examples of the thermal polymerization inhibitor include hydroquinone, p-methoxyphenol, 2,6-di-tert-butyl-p-cresol, pyrogallol, β-naphthol and the like. The addition amount of the thermal polymerization inhibitor is not particularly limited as long as it does not adversely affect the characteristics exhibited by the adhesive member according to the present invention. The range of 0.01 mass% or more and 5 mass% or less is preferable with respect to the composition for adhesive members (F).

  Examples of the anti-aging agent include hindered phenol-based compounds such as butylated hydroxytoluene and butylhydroxyanisole, benzotriazole-based compounds, and hindered amine-based compounds. The addition amount of the anti-aging agent is not particularly limited as long as it does not adversely affect the characteristics exhibited by the adhesive member according to the present invention. The range of 0.01 mass% or more and 5 mass% or less is preferable with respect to the composition for adhesive members (F).

  The composition (F) for an adhesive member in the present invention comprises 10 to 70% by mass of an unsaturated polyurethane prepolymer (A), 5 to 30% by mass of an alicyclic compound (B), and 10 to 10% of an alkyl (meth) acrylate (C). 65% by mass, monomer (D) 5 to 40% by mass, photopolymerization initiator (E) 0.2 to 5.0% by mass, and if necessary, a total of 100% by mass of (A) to (E) The silane coupling agent (G) can be obtained by adding 5.0% by mass or less and the flexibility-imparting agent (H) by 100% by mass or less and mixing them uniformly at room temperature or by heating. In addition, from the viewpoint of the corrosion resistance of the adhesive member, the acid value of the adhesive member is 1 mg KOH / g or less, specifically, a monomer containing an acid group in the composition for adhesive member (F), a prepolymer, a silane coupling agent, It is preferable not to use a softening agent.

  Corrosion resistance because the adhesive film composition (F) does not corrode transparent conductive films such as ITO films and ITO glass unless it contains monomers, prepolymers, silane coupling agents, and flexibility-imparting agents that contain acid groups. Can be improved.

  The adhesive member obtained by photopolymerizing the composition for adhesive member (F) preferably has a rubber hardness of JIS rubber hardness and a Shore A hardness of 1 or more and 25 or less. Compared to the case where the rubber hardness of the adhesive member is less than 1 Shore A hardness, when the Shore A hardness is 1 or more and 25 or less, deformation of the adhesive member due to pressure at the time of bonding is suppressed, and accurate bonding becomes possible. Preferably, when it is necessary to peel off the adhesive member, it is preferable because deformation is suppressed and reworkability is improved. Compared with the case where the rubber hardness of the adhesive member is larger than the Shore A hardness 25, it is preferable that the Shore hardness is 1 or more and 25 or less because the adhesive property of the adhesive member is increased and the impact resistance is improved.

  The viscosity of the adhesive member composition (F) of the present invention is not particularly defined, but is preferably in the range of 100 to 25000 mPa · s at 25 ° C. If it is lower than 100 mPa · s, the film thickness accuracy may decrease during the production of the adhesive member. When it exceeds 25000 mPa · s, pretreatment such as heating may be necessary before use.

  The active energy ray of the present invention refers to an electromagnetic wave or a charged particle beam having an energy quantum, that is, an active light such as an ultraviolet ray or an electron beam. As the active energy ray, ultraviolet rays are preferable. As the active energy ray source, for example, a high pressure mercury lamp, a halogen lamp, a xenon lamp, a metal halide lamp, an electron beam accelerator, a radioactive element or the like is preferable.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated further more concretely, this invention is not limited to these Examples. In the following, “part” and “%” are all based on mass unless otherwise specified.

<Production Example 1> [Production of unsaturated prepolymer (A-1)]
Hydrogenated polybutadiene (GI-2000 manufactured by Nippon Soda Co., Ltd.) (a1-1) having a hydroxyl group value of 47.6 mg KOH / g and a number-average molecular weight of 2100 in a Separa flask equipped with a stirrer, thermometer and reflux condenser (a1-1) 85. 11 parts by mass and 0.05 part by mass of 2,6-di-tert-butyl-p-cresol (hereinafter sometimes abbreviated as BHT) as a thermal polymerization inhibitor were charged, and isophorone diisocyanate (polyisocyanate) Hereinafter, 10.84 parts by mass of (which may be abbreviated as IPDI) (a2-1)) was added and reacted for 3 hours at 60 ° C. in a nitrogen atmosphere with good stirring to obtain a prepolymer precursor. Further, 2-hydroxyethyl methacrylate (a3-1) (hereinafter sometimes abbreviated as HEMA) as a compound having both a functional group having active hydrogen and an ethylenically unsaturated bond in the molecule of the reaction product. 96 parts by mass and 0.04 part by mass of dibutyltin dilaurate (hereinafter sometimes abbreviated as DBSL) as a catalyst were added, reacted at 80 ° C. for 3 hours, and absorption peak of 2230 cm ⁻¹ isocyanate group by IR measurement It was confirmed that disappeared. Thereafter, the reaction vessel was cooled to obtain an unsaturated prepolymer (A-1) which is an unsaturated polyurethane prepolymer containing a hydrogenated polybutadiene structure.

<Production Examples 2 to 5> [Production of unsaturated prepolymers (A-2) to (A-5)]
Unsaturated prepolymer (A-2) which is an unsaturated polyurethane prepolymer containing a hydrogenated polybutadiene structure having a number average molecular weight shown in Table 1 by performing the same operation as in Production Example 1 with the composition shown in Table 1. To (A-5) were obtained.

Explanation of abbreviations in Table 1 (a1-1): Water having a hydroxyl group obtained by hydrogenating polybutadiene having a number average molecular weight of 2100, a hydroxyl value of 47.6 mgKOH / g, and a 1,2-polybutadiene structure of 80% by mass or more. Polybutadiene GI-2000 (Nippon Soda Co., Ltd.)
(A1-2): Hydrogenated polybutadiene having a number average molecular weight of 3100, a hydroxyl value of 29.0 mgKOH / g, and a hydroxyl group obtained by hydrogenating a polybutadiene having a 1,2-polybutadiene structure of less than 80% by mass Krasol HLBH-P3000 ( (Sartomer)
(A2-1): Isophorone diisocyanate (a2-2): 1,6-hexamethylene diisocyanate (a3-1): 2-hydroxyethyl methacrylate (a3-2): 2-hydroxypropyl methacrylate (a3-3): polypropylene Glycol (n = 5) monomethacrylate (molecular weight 376)
(A3-4): Polyethylene glycol (n = 6) monomethacrylate (molecular weight 350)
BHT: 2,6-di-tert-butyl-p-cresol DBSL: dibutyltin dilaurate

<Production Example 6> [Production of unsaturated prepolymer (K-1)]
81.38 parts by mass of unhydrogenated polybutadiene (G-2000 manufactured by Nippon Soda Co., Ltd.) having a terminal hydroxyl group having a hydroxyl value of 50.0 mgKOH / g number average molecular weight in a Separa flask equipped with a stirrer, thermometer and reflux condenser And 0.05 parts by weight of BHT as a thermal polymerization inhibitor were added, and 10.08 parts by weight of IPDI (a2-1) was added as a polyisocyanate, and the mixture was reacted at 60 ° C. for 3 hours in a nitrogen atmosphere with good stirring. To obtain a prepolymer precursor. Further, this reaction product is converted to polypropylene glycol monomethacrylate (a3-2) (hereinafter sometimes abbreviated as PPMA) as a compound having both a functional group having active hydrogen and an ethylenically unsaturated bond in the molecule. .45 parts by mass and 0.04 parts by mass of DBSL as a catalyst were added and reacted at 80 ° C. for 3 hours, and it was confirmed by IR measurement that the absorption peak of 2230 cm ⁻¹ isocyanate group had disappeared. Thereafter, the reaction vessel was cooled to obtain an unsaturated prepolymer (K-1) which is an unhydrogenated unsaturated polyurethane prepolymer having a number average molecular weight of 30,000.

<Production Example 7> [Production of unsaturated prepolymer (K-2)]
100 parts by mass of ethyl acetate was put into a four-necked Separa flask equipped with a stirrer, thermometer, reflux condenser and nitrogen gas introduction tube, and heated under a nitrogen atmosphere to reflux the ethyl acetate. Next, 58.8 parts by mass of 2-ethylhexyl acrylate, 1.0 part by mass of acrylic acid, 0.06 part by mass of 2,2′-azobis (2-methylbutyronitrile), and 20 parts by mass of ethyl acetate were mixed. The mixture was added dropwise over a period of time under reflux of ethyl acetate, and reacted for 3 hours after completion of the addition to obtain a prepolymer solution having an acid value of 3.5 mgKOH / g. To the prepolymer solution, 0.1 part by weight of BHT as a thermal polymerization inhibitor and 0.1 part by weight of triphenylphosphine as a catalyst are charged into a reaction vessel, and 2.0 parts by weight of glycidyl methacrylate is added thereto and stirred well. The reaction was carried out at 80 ° C. for 8 hours in a nitrogen atmosphere, and it was confirmed that the acid value was 1.0 mgKOH / g or less. Then, after distilling off ethyl acetate, the reaction vessel was cooled to obtain an unsaturated prepolymer (K-2) which is an unsaturated polyacrylic prepolymer having a number average molecular weight of 30000.

<Production Example 8> [Production of unsaturated prepolymer (K-3)]
A reaction vessel was charged with 79.61 parts by mass of propylene glycol having a hydroxyl value of 56.0 mgKOH / g and a number average molecular weight of 2000, and BHT as a thermal polymerization inhibitor, and 11.04 parts by mass of IPDI as polyisocyanate. Was added and reacted at 60 ° C. for 3 hours in a nitrogen atmosphere with good stirring to obtain a prepolymer precursor. Further, 9.26 parts by mass of PPMA as a compound having both a functional group having active hydrogen and an ethylenically unsaturated bond in the molecule, and 0.04 parts by mass of DBSL as a catalyst were added to the reaction product, After reacting for 3 hours, it was confirmed by IR measurement that the absorption peak of the isocyanate group at 2230 cm ⁻¹ disappeared. Thereafter, the reaction vessel was cooled to obtain an unsaturated prepolymer (K-3) which is an unsaturated polyurethane prepolymer using a polyether-based polyurethane having a number average molecular weight of 20000 and containing no hydrogenated polybutadiene structure.

<Production Example 9> [Production of unsaturated prepolymer (K-4)]
Reaction of 85.46 parts by mass of poly [(3-methyl-1,5-pentanediol) -alt- (adipic acid)] having a hydroxyl value of 28.7 mgKOH / g and a number average molecular weight of 4000, and 0.05 part by mass of BHT Into a container, 6.81 parts by mass of IPDI was added as a polyisocyanate, and the mixture was allowed to react at 60 ° C. for 3 hours in a nitrogen atmosphere while stirring well to obtain a prepolymer precursor. Further, 7.64 parts by mass of PPMA as a compound having both a functional group having active hydrogen and an ethylenically unsaturated bond in the molecule and 0.04 parts by mass of DBSL as a catalyst were added to this reaction product, It reacted for time and it was confirmed by IR measurement that the absorption peak of the isocyanate group at 2230 cm ⁻¹ disappeared. Thereafter, the reaction vessel was cooled to obtain an unsaturated prepolymer (K-4) which is an unsaturated polyurethane prepolymer using a polyester-based polyurethane having a number average molecular weight of 21,000 and not containing a hydrogenated polybutadiene structure.

<Example 1>
50.0 parts by mass of unsaturated polyurethane prepolymer (A-1) produced in Production Example 1 and tricyclo [5.2.1.0 (2,6)] decan-8-yl (B-1) 19 methacrylate 0.0 part by mass, 10.0 parts by mass of 2-ethylhexyl acrylate (C-1), 20.0 parts by mass of 2-methoxyethyl acrylate (D-1), 1-hydroxycyclohexyl phenyl ketone (E -1) A uniform transparent composition for an adhesive member (F-1) was obtained by charging 1.0 part by mass into each container and stirring at about 60 ° C. for 1 hour.

<Examples 2 to 30>
Except having changed into the composition shown in Table 2, it carried out similarly to Example 1, and obtained the composition (F-2)-(F-30) for adhesive members.

<Comparative Example 1>
3. 30.0 parts by mass of the unsaturated prepolymer (K-1) produced in Production Example 7, tricyclo [5.2.1.0 (2,6)] decan-8-yl (B-1) methacrylate. 0 parts by mass, 35.0 parts by mass of 2-ethylhexyl acrylate (C-1), 20.0 parts by mass of 2-methoxyethyl acrylate (D-1), 1-hydroxycyclohexyl phenyl ketone (E- 1) 1.0 mass part was prepared for each container and stirred at about 60 ° C. for 1 hour to obtain a uniform and transparent composition for an adhesive member for comparative example (J-1).

<Comparative Examples 2 to 16>
Except having changed into the composition shown in Table 3, it carried out similarly to the comparative example 1, and obtained the composition for adhesive members for comparative examples (J-2)-(J-16).

Table 2 and abbreviations in Table 3 Description A: Unsaturated Prepolymer _{^{B: CH 2 = C (R}} 1) -COO- (R 2 -O) n-R 3 (1)
R ¹ is H or CH ₃ , R ² is CH ₂ CH ₂ or CH ₂ CH (CH ₃ ), and R ³ is cycloalkyl, cycloalkenyl, bicycloalkyl, bicycloalkenyl, tricycloalkyl, tricycloalkenyl And n is 0 or 1.
^{_{C: CH 2 = C (R}} 1) -COO-R 2 (2)
R ¹ is H or CH ₃ and R ² is a linear or branched alkyl having 8 to 18 carbon atoms.
^{_{(D): CH 2 = C}} (R 1) -COO- (R 2 -O) n-R 3 (3)
R ¹ is H or CH ₃ , R ² is alkylene having 2 to 4 carbon atoms, R ³ is H or linear or branched alkyl having 1 to 4 carbon atoms, and n is 1 to 10.
E: photopolymerization initiator G: silane coupling agent H: flexibility imparting agent I: ethylenically unsaturated monomers other than (B) to (D)

(B-1): tricyclomethacrylate [5.2.1.0 (2,6)] decan-8-yl (B-2): cyclohexyl methacrylate (B-3): [(1S, 4S) -1 , 7,7-trimethyl-6-bicyclo [2.2.1] heptanyl] acrylate (B-4): [(1S, 4S) -1,7,7-trimethyl-6-bicyclo [2.2.1]. ] Heptanyl] methacrylate (B-5): Methacrylic acid 2-[(3a, 4,5,6,7,7a-hexahydro-4,7-methano-1H-inden-6-yl) oxy] ethyl ester (C -1): 2-ethylhexyl acrylate (C-2): n-dodecyl methacrylate (C-3): n-octadecyl methacrylate (C-4): 2-ethylhexyl methacrylate (C-5): acrylic acid n-dodecyl (D-1 ): 2-methoxyethyl acrylate,
(D-2): Polypropylene glycol (n = 5) monomethacrylate (D-3): 2-ethoxyethyl methacrylate (D-4): 2-butoxydiethylene glycol methacrylate (D-5): 4-hydroxybutyl acrylate (E-1): 1-hydroxy-cyclohexyl-phenyl-ketone (E-2): 2,2-dimethoxy-1,2-diphenylethane-1-one (G-1): 3-glycidoxypropyltri Methoxysilane (G-2): 3-methacryloxypropyltrimethoxysilane (H-1): polybutadiene B-1000 having a number average molecular weight of 1100 (manufactured by Nippon Soda Co., Ltd.)
(H-2): Terpene-based hydrogenated resin Clearon P85 (manufactured by Yasuhara Chemical Co., Ltd.)
(I-1): n-butyl methacrylate (I-2): polypropylene glycol (n = 7) dimethacrylate (I-3): methyl methacrylate (I-4): t-butyl methacrylate (I-5 ): Benzyl acrylates (A-1) to (A-5) and (K-1) to (K-4) are unsaturated prepolymers (A-1) obtained in Production Examples 1 to 9, respectively. To (A-5) and (K-1) to (K-4).

  Regarding the adhesive member compositions (F-1) to (F-30) and the adhesive member compositions (J-1) to (J-16) obtained as described above, the following adhesive members were used. Basic physical properties were evaluated. The results are shown in Tables 4 and 5.

<Measurement of acid value of composition for adhesive member>
The obtained adhesive member composition (F) or comparative adhesive member composition (J) was dissolved in tetrahydrofuran and measured by an acid-base titration method using potassium hydroxide in accordance with JIS K0070. The acid values are all less than 0.1, indicating that the corrosion resistance is good.

<Measurement of rubber hardness of adhesive member>
A PET film having a thickness of 100 μm was brought into close contact with a horizontally placed glass plate, and the composition for an adhesive member (F) or the composition for an adhesive member for a comparative example (J) obtained thereon was 40 mm × 40 mm. The film was applied to a thickness of 3 mm, and a PET film having a thickness of 25 μm was further stacked thereon, and then cured by exposure for 10 minutes using a chemical lamp having a wavelength of 360 nm (illuminance of about 3 mW / cm ² ). . Thereafter, two cured products obtained by removing the PET film were stacked and measured according to JIS K6253 “Rubber hardness test method”. The lower the numerical value, the better the flexibility. The results are shown in Tables 4 and 5.

<Creation of sheet member>
An adhesive film composition (F) or a comparative adhesive composition composition (J) obtained on the release-treated surface was adhered to a 50 μm-thick PET film on a horizontally placed glass plate. Is applied so that the thickness is 50 μm, and a 38 μm-thick peeled PET film is further bonded so that bubbles do not enter, and a chemical lamp with a wavelength of 360 nm (illuminance of about 3 mW / cm ² ) is used. Then, it was cured by exposure for 5 minutes to prepare a sheet member.

<Transparency of adhesive member>
The previously produced sheet member was cut to a size of 25 mm × 50 mm, and the 38 μm peel-treated PET film was peeled off, and then the exposed adhesive member surface was placed on a slide glass (“S1112” manufactured by Matsunami Glass Industrial Co., Ltd.). After laminating without winding, the peeled PET film having a thickness of 50 μm was peeled off to prepare a test piece, and the haze of the test piece was measured according to JIS K7136. Was subtracted from the measured value to obtain the haze value of the sample, and evaluated according to the following criteria: If the haze value is less than 0.5%, it is a good result with high transparency, and is not less than 0.5 and less than 1.0%. However, there was no problem with transparency, and it was at a practical level.When the haze value was 1.0 or more and less than 5.0%, the adhesive member was clouded, causing a problem with transparency. When the content is 0.0% or more, white turbidity is visible, which is not suitable for practical use.
○: Less than 0.5% ○ △: 0.5% or more and less than 1.0% △: 1.0% or more and less than 5.0% ×: 5.0% or more

<Measurement of adhesive strength and reworkability of adhesive members>
The previously produced sheet member was cut to a size of 25 × 100 mm, the 38 μm peel-treated PET film was peeled off, and then the exposed adhesive member surface was bonded to a 75 μm thick easy-adhesive PET support. Next, the 50 μm peel-treated PET film was peeled off, and the exposed adhesive member surface was float glass having a width of 30 mm × length of 100 mm × thickness of 2.0 mm, and an acrylic plate having a width of 30 mm × length of 100 mm × thickness of 2.0 mm ( The product was affixed to Mitsubishi Rayon Co., Ltd. (trade name “Acrylite MR-200”) without any entrainment of bubbles to obtain a test piece. Next, the test piece was placed in an autoclave and treated at 40 ° C. and 0.5 MPa for 30 minutes. After taking out from the autoclave and leaving the test pieces for 24 hours under the condition of 23 ° C. and 50% humidity, each test piece was placed in a tensile tester and peeled at 180 ° peeling angle and 300 mm / min at 23 ° C. and 50% humidity. The sheet was peeled from the glass interface and the acrylic interface at a speed, and the adhesion strength to the glass and the acrylic plate was measured. Moreover, after peeling in a 180 degree direction, the state of the glass plate surface was observed visually, and rework property was evaluated according to the following references | standards. As a result, if the glass plate surface does not show any haze or adhesive residue, it shows good reworkability. Even if the glass plate surface shows almost no fogging and adhesive residue, it has a practical level of reworkability. Show. On the other hand, when cloudiness etc. are recognized on the surface of a glass plate, it has shown that it is inferior to rework property, and when adhesive residue is recognized, rework property is a result unsuitable for practical use. The results are shown in Tables 4 and 5.
○: No fogging or adhesive residue is observed on the glass plate surface.
○ △: Almost no fogging or the like is observed on the glass plate surface.
(Triangle | delta): Cloudiness etc. are recognized by the glass plate surface.
X: Adhesive residue is recognized on the glass plate surface.

<Adhesion reliability of adhesive members at high temperature and high humidity>
The previously produced sheet member was cut to a size of 25 × 100 mm, the 38 μm peel-treated PET film was peeled off, and then the exposed adhesive member surface was bonded to a 75 μm thick easy-adhesive PET support. Next, the 50 μm peel-treated PET film was peeled off, and the exposed adhesive member surface was bonded to a float glass having a width of 30 mm × length of 100 mm × thickness of 2.0 mm to obtain a test piece. Next, the test piece was placed in an autoclave and treated at 40 ° C. and 0.5 MPa for 30 minutes. The product was taken out from the autoclave, allowed to stand for 24 hours under conditions of 25 ° C. and 50% humidity, and then allowed to stand for 72 hours under conditions of 65 ° C. and humidity of 90%. The state of the test piece taken out after 72 hours was visually observed, and the adhesion reliability was evaluated according to the following criteria. As a result, good adhesion reliability is shown if no foaming, whitening, or peeling is observed on the test piece. Even when almost no foaming, whitening, or peeling is observed on the test piece, the adhesion is at a practical level. It shows reliability. On the other hand, when foaming or whitening is observed on the test piece, it indicates that the adhesion reliability is inferior, and when peeling is observed on the test piece, the adhesion reliability is not suitable for practical use. The results are shown in Tables 4 and 5.
○: No foaming, whitening, or peeling is observed on the test piece.
○ △: Foaming, whitening and peeling are hardly observed on the test piece.
Δ: Foaming or whitening is observed in the test piece.
X: Peeling is observed on the test piece.

  As is apparent from the results of Tables 4 and 5, the adhesive members obtained by photocuring the adhesive member compositions (F-1) to (F-30) obtained in Examples 1 to 30 are transparent, All evaluations of flexibility, corrosion resistance, adhesion, reworkability, and adhesion reliability are good.

  Comparing Example 6 and Comparative Example 1 in which the number average molecular weight of the unsaturated polyurethane prepolymer is comparable, it is an unsaturated polyurethane prepolymer using polybutadiene having an unhydrogenated hydroxyl group in the composition for an adhesive member. Adhesion with excellent flexibility, adhesiveness and adhesion reliability by changing unsaturated prepolymer (K-1) to unsaturated prepolymer (A-4), which is an unsaturated polyurethane prepolymer containing a hydrogenated polybutadiene structure It turns out that a member can be obtained.

  Comparing Example 6 and Comparative Example 2 in which the number average molecular weight of the unsaturated prepolymer is comparable, the unsaturated polyacrylic prepolymer mainly composed of 2-ethylhexyl acrylate in the adhesive member composition Transparency, flexibility, adhesiveness and adhesion reliability are excellent by changing the prepolymer (K-2) to an unsaturated prepolymer (A-4) which is an unsaturated polyurethane prepolymer having a hydrogenated polybutadiene structure. It can be seen that an adhesive member can be obtained.

  Comparing Example 5 and Comparative Example 3 in which the number average molecular weight of the unsaturated polyurethane prepolymer is comparable, an unsaturated polyurethane prepolymer using a polyether-based polyurethane having no hydrogenated polybutadiene structure in the adhesive member composition By changing the unsaturated prepolymer (K-3), which is an unsaturated prepolymer (A-3), which is an unsaturated polyurethane prepolymer containing a hydrogenated polybutadiene structure, adhesion with excellent adhesion and adhesion reliability. It turns out that a member can be obtained.

  Comparing Example 5 and Comparative Example 4 in which the number average molecular weight of the unsaturated polyurethane prepolymer is comparable, the unsaturated polyurethane prepolymer using a polyester-based polyurethane having no hydrogenated polybutadiene structure in the adhesive member composition By changing an unsaturated prepolymer (K-4) to an unsaturated prepolymer (A-3) that is an unsaturated polyurethane prepolymer containing a hydrogenated polybutadiene structure, transparency, adhesiveness, and adhesion reliability are improved. It can be seen that an excellent adhesive member can be obtained.

  When Example and Comparative Example 5 (when the content of unsaturated polyurethane prepolymer (A) containing a hydrogenated polybutadiene structure is low) are compared, the unsaturated polyurethane prepolymer (A) is 10 to 10 in the adhesive member composition. It turns out that the adhesive member which is excellent in adhesiveness, rework property, and adhesive reliability can be obtained by containing 50 mass%. On the other hand, when Examples and Comparative Example 6 (when the content of the unsaturated polyurethane prepolymer (A) containing a hydrogenated polybutadiene structure is high) are compared, the unsaturated polyurethane prepolymer (A) in the adhesive member composition is compared. It turns out that the adhesive member which is excellent in transparency, adhesiveness, rework property, and adhesive reliability can be obtained by containing 10-50 mass%.

  When Examples and Comparative Example 7 (when the content of the alicyclic compound (B) is small) are compared, the composition for an adhesive member contains 5 to 30% by mass of the alicyclic compound (B). It turns out that the adhesive member which is excellent in adhesiveness and adhesive reliability can be obtained. On the other hand, when an Example and the comparative example 8 (when there is much content of an alicyclic compound (B)), 5-30 mass% of alicyclic compounds (B) are contained in the composition for adhesive members. Thus, it can be seen that an adhesive member having excellent transparency, flexibility and reworkability can be obtained.

  When Examples 5 and 14 to 17 were compared with Comparative Example 9 (when methyl methacrylate (I-3) which is a monomer having no alicyclic structure was used instead of alicyclic compound (B)), adhesion was observed. It turns out that the adhesive member which is excellent in adhesiveness and adhesive reliability can be obtained by containing an alicyclic compound (B) in the composition for members.

  Examples 5 and 14 to 17 and Comparative Example 10 (when t-butyl methacrylate (I-4) which is a monomer having no alicyclic structure is used in place of the alicyclic compound (B)) and Comparative Example 11 When compared with (when benzyl acrylate (I-5) having an aromatic ring structure is used instead of alicyclic compound (B)), the composition for adhesive members contains alicyclic compound (B). Thus, it can be seen that an adhesive member having excellent adhesion, reworkability, and adhesion reliability can be obtained.

  When Example 5 and Comparative Example 12 (when the content of monomer (D) is low) are compared, the composition for adhesive member contains 5 to 40% by mass of monomer (D). It can be seen that an adhesive member having excellent properties can be obtained. On the other hand, when Example 5 and Comparative Example 13 (when the content of the monomer (D) is large) are compared, the composition contains 5 to 40% by mass of the monomer (D) in the adhesive member composition. It turns out that the adhesive member which is excellent in adhesiveness and adhesive reliability can be obtained.

  When Examples 5, 18, and 19 were compared with Comparative Example 14 (when n-butyl methacrylate (I-1) having a short alkyl chain length was used instead of alkyl (meth) acrylate (C)), an adhesive member It turns out that the adhesive member which is excellent in adhesiveness and rework property can be obtained by containing the alkyl (meth) acrylate (C) in the composition for use.

  When Examples 5, 27 and 28 are compared with Comparative Example 16 (when the content of the photopolymerization initiator (E) is small), the alicyclic compound (B) is contained in the adhesive member composition in an amount of 5 to 30% by mass. It turns out that the adhesive member which is excellent in adhesiveness, rework property, and adhesive reliability can be obtained by containing. On the other hand, when Examples 18, 25 and 26 and Comparative Example 15 (when the content of the photopolymerization initiator (E) is high) are compared, the alicyclic compound (B) is 5-30 in the adhesive member composition. It turns out that the adhesive member which is excellent in adhesiveness, rework property, and adhesive reliability can be obtained by containing the mass%.

  The composition for an adhesive member of the present invention is excellent in transparency, adhesiveness, adhesive reliability at high temperature and high humidity, reworkability, and flexibility, and can provide an adhesive member that does not substantially contain an acid group. Moreover, since the adhesive member of the present invention has high transparency and is excellent in adhesion to glass and acrylic and reworkability, it can be used as an adhesive member used in the manufacture of image display devices such as liquid crystal panels and plasma displays. Moreover, since it does not contain an acid group substantially, it is excellent in corrosion resistance and can be used as an adhesive member used in the production of an optical panel using a conductive material such as a touch panel. In addition, since it is cured with active energy rays, it is easy to obtain adhesive members of various shapes and thicknesses, and can be used for various purposes in a wide range where general-purpose adhesive members are used. I can think of it.

Claims (8)

The following unsaturated polyurethane prepolymer (A): 10 to 50% by mass, alicyclic compound (B) represented by the following general formula (1): 5 to 30% by mass, alkyl represented by the following general formula (2) (meta ) Acrylate (C) 10 to 65% by mass, monomer (D) represented by the following general formula (3) 5 to 40% by mass, photopolymerization initiator (E) 0.2 to 5.0% by mass A composition for an adhesive member.
(A) an unsaturated polyurethane prepolymer comprising a hydrogenated polybutadiene structure ^{_{(B) CH 2 = C (}} R 1) -COO- (R 2 -O) n-R 3 (1)
R ¹ is H or CH ₃ , R ² is CH ₂ CH ₂ or CH ₂ CH (CH ₃ ), and R ³ is cycloalkyl, cycloalkenyl, bicycloalkyl, bicycloalkenyl, tricycloalkyl, tricycloalkenyl And n is 0 or 1.
^{_{(C) CH 2 = C (}} R 1) -COO-R 2 (2)
R ¹ is H or CH ₃ and R ² is a linear or branched alkyl having 8 to 18 carbon atoms.
^{_{(D) CH 2 = C (}} R 1) -COO- (R 2 -O) n-R 3 (3)
R ¹ is H or CH ₃ , R ² is alkylene having 2 to 4 carbon atoms, R ³ is H or linear or branched alkyl having 1 to 4 carbon atoms, and n is 1 to 10.   The hydrogenated polybutadiene structure of the unsaturated urethane prepolymer (A) is derived from a hydrogenated polybutadiene obtained by hydrogenating a polybutadiene having a 1,2-polybutadiene structure of 80% by mass or more. The composition for adhesive members.   The composition for an adhesive member according to claim 1 or 2, wherein the alicyclic compound (B) is a methacrylic acid ester containing a bicycloalkyl group and / or a tricycloalkyl group.   The acid value is 1 mgKOH / g or less, The composition for adhesive members of any one of Claims 1-3 characterized by the above-mentioned.   The total amount of unsaturated polyurethane prepolymer (A), alicyclic compound (B), alkyl (meth) acrylate (C), monomer (D), and photopolymerization initiator (E) is 5.0% by mass. The composition for an adhesive member according to any one of claims 1 to 4, comprising a silane coupling agent (G) in an amount of not more than mass%.   100 mass% with respect to a total of 100 mass% of unsaturated polyurethane prepolymer (A), alicyclic compound (B), alkyl (meth) acrylate (C), monomer (D) and photopolymerization initiator (E). The composition for adhesive members according to any one of claims 1 to 5, comprising the following flexibility-imparting agent (H).   An adhesive member having a Shore A hardness of 1 or more and 25 or less obtained by polymerizing the composition for an adhesive member according to any one of claims 1 to 6 with active energy rays.   The adhesive member according to claim 7, wherein the adhesive member is a double-sided adhesive sheet.