Adhesive polarizing films and laminates for image display devices

Abstract

This invention provides an adhesive polarizing film capable of suppressing the increase in surface resistivity of an adhesive layer under high-temperature conditions. According to the invention, an adhesive polarizing film is provided, which is composed of an adhesive layer and a polarizing film laminated together, wherein the adhesive layer is formed of an adhesive composition containing an adhesive and a conductive polymer, and the storage modulus (G') of the adhesive layer at 80°C is 20–1000 kPa.

Description

[Technical Field]

[0001] This invention relates to an adhesive polarizing film and a laminate for an image display device. [Background Technology]

[0002] As disclosed in Patent Document 1, the image display component is composed of multiple components, and adhesives (adhesive layers) have traditionally been used to bond the various components together.

[0003] [Existing Technical Documents]

[0004] [Patent Documents]

[0005] [Patent Document 1] International Publication No. 2014 / 042248 [Summary of the Invention]

[0006] [The problem the invention aims to solve]

[0007] In image display components, static electricity buildup on various parts can cause image display abnormalities. To prevent this buildup, the adhesive used to bond the image display components must have a low resistance value. One method to reduce the resistance of the adhesive (adhesive layer) is to combine it with conductive materials such as conductive polymers.

[0008] Image display components are sometimes exposed to high temperatures or high temperature and high humidity environments, which can cause shrinkage of the components. If the adhesive layer used for bonding the components also shrinks as the components shrink, the configuration of conductive polymers in the adhesive layer may be disrupted, leading to an increase in the surface resistivity of the adhesive layer.

[0009] The present invention was made in view of the following circumstances, and provides an adhesive polarizing film capable of suppressing the increase of surface resistivity of the adhesive layer under high temperature conditions.

[0010] [Solutions]

[0011] According to the present invention, an adhesive polarizing film is provided, which is composed of an adhesive layer and a polarizing film laminated together, wherein the adhesive layer is formed of an adhesive composition containing an adhesive and a conductive polymer, and the storage modulus (G') of the adhesive layer at 80°C is 20 to 1000 kPa.

[0012] The adhesive polarizing film of the present invention has a high storage modulus even at high temperatures such as 80°C. Therefore, even when the polarizing film shrinks due to heat, the shrinkage of the adhesive layer can be suppressed, thereby suppressing the increase in surface resistivity caused by the shrinkage of the adhesive layer. [Attached Image Description]

[0013]

【 Figure 1 A layer structure diagram of an adhesive polarizing film 1 according to an embodiment of the present invention.

[0014]

【 Figure 2 [A layer structure diagram of a laminate 5 for an image display device according to an embodiment of the present invention.]

Detailed Implementation Methods

[0015] The following describes the specific embodiments of the present invention.

[0016] 1. Adhesive polarizing film

[0017] like Figure 1 As shown, the adhesive polarizing film 1 of one embodiment of the present invention is composed of an adhesive layer 2 and a polarizing film 3 laminated together. Preferably, a release film 4 for protecting the adhesive surface 1a is provided on the adhesive surface 1a of the adhesive polarizing film 1. The release film 4 may be made of PET or the like.

[0018] The following explains each structure.

[0019] 1-1. Adhesive layer 2

[0020] The adhesive layer 2 is formed from an adhesive composition containing an adhesive and a conductive polymer. The conductive polymer imparts conductivity to the adhesive layer 2, thereby reducing its surface resistivity.

[0021] The storage modulus (G') of the adhesive layer 2 at 80°C is 20–1000 kPa. Hereinafter, unless otherwise stated, the storage modulus refers to the storage modulus (G') at 80°C, and the measurement frequency is 1 Hz. By keeping the storage modulus within this range, the increase in surface resistivity caused by the shrinkage of the adhesive layer 2 at high temperatures is suppressed. Specifically, this storage modulus is, for example, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400, 500, 600, 700, 800, 900, or 1000 kPa, or within any range between two values ​​exemplified herein. The storage modulus of the adhesive layer 2 can be adjusted by changing the composition of the adhesive.

[0022] The thickness of the adhesive layer 2 is typically 5–75 μm, preferably 10–50 μm, depending on the dry film thickness.

[0023] 1-2. Adhesive

[0024] The adhesive is composed of any adhesive capable of dispersing conductive polymers. Examples of adhesives include acrylic adhesives and rubber adhesives.

[0025] 1-2-1. Acrylic adhesives

[0026] Acrylic adhesives are adhesives that comprise (meth)acrylic polymers and crosslinking agents. (Meth)acrylic polymers are polymers comprising repeating structures composed of (meth)acrylic unit structures. Unit structures derived from (meth)acrylates can be cited as examples of (meth)acrylic unit structures.

[0027] When the adhesive is an acrylic adhesive, the storage modulus of the adhesive layer 2 is preferably 20 to 200 kPa. This is because if the storage modulus is too high, the adhesive strength may become too low. Specifically, this storage modulus is, for example, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, or 200 kPa, or may be within the range of any two values ​​exemplified herein.

[0028] When the adhesive is an acrylic adhesive, the storage modulus of the adhesive layer 2 can be adjusted by changing the storage modulus of the (meth)acrylic polymer alone or by changing the content of the crosslinking agent.

[0029] <(Meth)Acrylic Polymers>

[0030] The storage modulus of the (meth)acrylic acid polymer is preferably 20 to 200 kPa, more preferably 30 to 100 kPa. Specifically, this storage modulus is, for example, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200 kPa, or may be within the range of any two values ​​exemplified herein.

[0031] Even when the storage modulus of the polymer alone is low, increasing the amount of crosslinking agent can improve the storage modulus of the adhesive layer 2, but this may reduce the toughness of the polymer. Therefore, the storage modulus of the polymer alone is preferably within the above range.

[0032] The weight-average molecular weight (Mw) of the (meth)acrylic acid polymer is, for example, 400,000 to 3,000,000, preferably 600,000 to 2,500,000, and more preferably 1,000,000 to 2,000,000. In this case, the storage modulus of the (meth)acrylic acid polymer is likely to be a preferred value. Specifically, this Mw is, for example, 400,000, 500,000, 600,000, 700,000, 800,000, 900,000, 1,000,000, 1,100,000, 1,200,000, 1,300,000, 1,400,000, 1,500,000, 1,600,000, 1,700,000, 1,800,000, 1,900,000, 2,000,000, 2,500,000, and 3,000,000, or within any range between any two values ​​exemplified herein. Mw is determined by gel permeation chromatography (GPC).

[0033] The molecular weight distribution (Mw / Mn; Mn is the number average molecular weight) of the (meth)acrylic acid polymer is, for example, 1 to 15, preferably 5 to 10. Specifically, this value is, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or within any range between any two values ​​exemplified herein. Mn is determined by GPC in the same manner as Mw.

[0034] (Meth)acrylic polymers are preferably polymers comprising a monomer mixture of the first and second monomers. If the monomer mixture comprises 100% by mass, the content of the first monomer is preferably 0.05 to 10% by mass, and the content of the second monomer is preferably 51 to 99.5% by mass. The monomer mixture may contain a third monomer. The content of the third monomer is the balance after subtracting the contents of the first and second monomers from 100% by mass. When a (meth)acrylic polymer is formed using such a compounded monomer mixture, the storage modulus of the (meth)acrylic polymer is readily preferred.

[0035] The content of the first monomer is preferably 1 to 5% by mass. Specifically, this content is, for example, 0.05, 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10% by mass, or within any range between two values ​​exemplified herein.

[0036] The content of the second monomer is preferably 60 to 99.5% by mass. Specifically, this content is, for example, 51, 55, 60, 65, 70, 75, 80, 85, 90, 95, 96, 97, 98, 99, 99.5% by mass, or within any two values ​​exemplified herein.

[0037] ·First Monomer

[0038] The first monomer is a monomer containing cross-linking functional groups.

[0039] "Crosslinkable functional groups" refer to functional groups that, when added as polymer components to polymer chains, allow the polymer chains to form three-dimensional crosslinks within the adhesive layer system through reactions with other functional groups in the polymer chains or with a crosslinking agent during the formation of the adhesive layer. Examples of such crosslinkable functional groups include hydroxyl, amino, and carboxyl groups.

[0040] Monomers having hydroxyl groups as crosslinking functional groups include, for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 2-hydroxy-3-chloropropyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, ethylene glycol (meth)acrylate, polyethylene glycol (meth)acrylate, and polypropylene glycol (meth)acrylate. One of these monomers can be used alone or in combination with two or more.

[0041] Monomers having an amino group as a crosslinking functional group include, for example, N,N-dimethylaminoethyl (meth)acrylate, N,N-diethylaminoethyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylamide, N,N'-dimethylaminoethyl (meth)acrylamide, N,N'-dimethylaminopropyl (meth)acrylamide, acrylamide, etc., and one of them can be used alone or in combination of two or more.

[0042] Monomers with a carboxyl group as a crosslinking functional group, such as (meth)acrylic acid, crotonic acid, maleic acid, itaconic acid, citraconic acid, maleic anhydride, itaconic anhydride, etc., can be used alone or in combination of two or more.

[0043] Among monomers with crosslinking functional groups, monomers with hydroxyl groups are preferred from the viewpoint that they can easily form a three-dimensional crosslinked structure within the adhesive layer system. More specifically, 2-hydroxyethyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and 6-hydroxyhexyl (meth)acrylate are preferred.

[0044] ·Second monomer

[0045] The second monomer is not the first monomer, but is selected from at least one of alkyl (meth)acrylates with a glass transition temperature (Tg) of -60 to 20°C for the homopolymer, and alkoxyalkyl (meth)acrylates with a glass transition temperature of -60 to 20°C for the homopolymer. The glass transition temperature (Tg) of the homopolymer is the value described in Polymer Handbook Fourth Edition (Wiley-Interscience 1999).

[0046] Examples of such alkyl methacrylates include butyl acrylate (-50°C), methyl acrylate (8°C), octyl methacrylate (-20°C), isooctyl methacrylate (-45°C), 2-ethylhexyl methacrylate (-10°C), isodecanyl methacrylate (-41°C), and isostearyl methacrylate (-18°C). Examples of such alkoxyalkyl methacrylates include 2-methoxyethyl acrylate (-50°C) and methoxy-triethylene glycol acrylate (-50°C). The temperatures in parentheses for the second and third monomers are the Tg of the homopolymer.

[0047] The Tg of the second monomer is specifically, for example, -60, -50, -40, -30, -20, -10, 0, 10, 20°C, or within any range between any two values ​​exemplified here.

[0048] ·Third monomer

[0049] The third monomer is not either the first or the second monomer. Such a monomer is an alkyl (meth)acrylate or alkoxyalkyl (meth)acrylate, or other (meth)acrylates, or other monomers with vinyl unsaturated double bonds, which are outside the scope specified for the second monomer.

[0050] • Aggregation methods

[0051] The above monomer mixture is polymerized using various known methods such as solution polymerization, emulsion polymerization, and bulk polymerization to obtain (meth)acrylic acid polymers. From the viewpoint of balancing adhesive properties such as adhesion and holding power, or cost, solution polymerization is preferred. Ethyl acetate, toluene, etc., can be used as solvents for solution polymerization. The solution concentration is typically around 20–80% by weight. Various known initiators, such as azo-based and peroxide-based initiators, can be used as polymerization initiators. Chain transfer agents can be used to adjust the molecular weight. The reaction temperature is typically 50–80°C, and the reaction time is typically 1–8 hours.

[0052] <Cross-linking agent>

[0053] From the viewpoint of giving the adhesive appropriate cohesive strength, it is preferable to introduce a cross-linked structure into the (meth)acrylic polymer. For example, a cross-linking agent is added to the solution after polymerization of the (meth)acrylic polymer, and heating is performed as needed to introduce the cross-linked structure. Examples of cross-linking agents include isocyanate-based cross-linking agents, epoxy-based cross-linking agents, oxazoline-based cross-linking agents, aziridine-based cross-linking agents, carbodiimide-based cross-linking agents, and metal chelate-based cross-linking agents. These cross-linking agents react with the cross-linking functional groups introduced into the (meth)acrylic polymer to form the cross-linked structure.

[0054] Since cross-linking structures can be introduced into (meth)acrylic polymers through heating, it is preferable to use cross-linking agents that have two or more isocyanate groups in one molecule. Examples of polyisocyanate crosslinking agents include, for instance, lower aliphatic polyisocyanates such as succinate and hexamethylene diisocyanate; alicyclic isocyanates such as cyclopentene diisocyanate, cyclohexene diisocyanate, and isophorone diisocyanate; aromatic isocyanates such as 2,4-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, and phenylenediamine diisocyanate; trimethylolpropane / toluene diisocyanate trimer adducts (e.g., Tosoh's "Coronate L"), trimethylolpropane / hexamethylene diisocyanate trimer adducts (e.g., Tosoh's "Coronate HL"), trimethylolpropane adducts of phenylenediamine diisocyanate (e.g., Mitsui Chemicals' "Takenate D110N"), and isocyanurates of hexamethylene diisocyanate (e.g., Tosoh's "Coronate L"). Isocyanate adducts such as "HX" and "Y-75" prepared by Zongyan Chemical.

[0055] The amount of crosslinking agent relative to 100 parts by weight of the (meth)acrylic polymer is, for example, 0.005 to 2 parts by weight, preferably 0.01 to 1 part by weight, and more preferably 0.05 to 0.15 parts by weight. The storage modulus of the adhesive layer 2 is generally preferred. Specifically, this amount is, for example, 0.005, 0.01, 0.05, 0.10, 0.15, 0.20, 0.50, 1.0, or 2.0 parts by weight, or may be within the range of any two values ​​exemplified herein.

[0056] 1-2-2. Rubber-based adhesives

[0057] Examples of rubber-based adhesives include rubber-based adhesive compositions using natural or synthetic rubber as polymers, preferably comprising hydrogenated block copolymers, tackifying resins, and softeners.

[0058] <Hydrogenated block copolymer>

[0059] Block copolymers are thermoplastic elastomers having segments (hard segments) composed of polymeric components of aromatic vinyl monomers and segments (soft segments) composed of polymeric components of conjugated diene monomers. Here, more specifically, the aromatic vinyl compounds are preferably styrene or α-methylstyrene (more preferably styrene), and the conjugated diene compounds are preferably butadiene or isoprene.

[0060] Specific examples of hydrogenated block copolymers include styrene-(ethylene-propylene)-styrene block copolymers (SEPS) (a hydrogenated form of styrene-isoprene-styrene block copolymer (SIS)), styrene-(butadiene-butene)-styrene block copolymers (SBBS) (a hydrogenated form of styrene-(ethylene-butene)-styrene block copolymer (SEBS) (a hydrogenated form of styrene-butadiene-styrene block copolymer (SBS)), styrene-(ethylene-propylene)-type block copolymers (SEP) (a hydrogenated form of styrene-isoprene block copolymer (SI)), and styrene-(ethylene-butene)-type block copolymers (SEB) (a hydrogenated form of styrene-butadiene block copolymer (SB)). From the viewpoint of excellent compatibility with tackifying resins, ABA-type hydrogenated block copolymers such as styrene-(ethylene-propylene)-styrene block copolymers (SEPS) and styrene-(ethylene-butene)-styrene block copolymers (SEBS) are preferred. These can be used individually or in combination of two or more.

[0061] <Tackifying Resin>

[0062] The tackifying resin has the property of being compatible with the hard segments constituting the hydrogenated block copolymer. The tackifying resin can be, for example, an aromatic tackifying resin. From the viewpoint of compatibility, the molecular weight of the aromatic tackifying resin used as the tackifying resin is preferably 5,000 or less.

[0063] The softening point of the tackifying resin is preferably 80°C or higher. This softening point is, for example, 80 to 200°C, specifically 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200°C, or within any two values ​​exemplified herein.

[0064] Examples of aromatic tackifying resins that can be used as tackifying resins include aromatic petroleum resins, styrene polymers, α-methylstyrene polymers, styrene-(α-methylstyrene) copolymers, styrene-aliphatic hydrocarbon copolymers, styrene-(α-methylstyrene)-aliphatic hydrocarbon copolymers, and styrene-aromatic hydrocarbon copolymers. More specifically, for example, commercially available styrene-aromatic hydrocarbon copolymers such as FMR-0150 (softening point 145°C, manufactured by Mitsui Chemicals), FTR-6100 (softening point 100°C, manufactured by Mitsui Chemicals), FTR-6110 (softening point 110°C, manufactured by Mitsui Chemicals), and FTR-6125 (softening point 125°C, manufactured by Mitsui Chemicals) can be used as styrene-aromatic hydrocarbon copolymers; FTR-7100 (softening point 100°C, manufactured by Mitsui Chemicals) as styrene (α-methylstyrene)-aliphatic hydrocarbon copolymers; FTR-8120 (softening point 120°C, manufactured by Mitsui Chemicals) as a styrene-based polymer; and SX-100 (softening point 100°C, manufactured by YASUHARA) can also be used as styrene-aromatic hydrocarbon copolymers. The following are examples of styrene (α-methylstyrene) copolymers: FTR-0100 (softening point 100℃, manufactured by Mitsui Chemicals), FTR-2120 (softening point 120℃, manufactured by Mitsui Chemicals), FTR-2140 (softening point 145℃, manufactured by Mitsui Chemicals), Kristalex 3100 (softening point 100℃, manufactured by Eastman Chemicals), Kristalex 3085 (softening point 85℃, manufactured by Eastman Chemicals), Kristalex 5140 (softening point 140℃, manufactured by Eastman Chemicals), Kristalex 1120 (softening point 120℃, manufactured by Eastman Chemicals), Kristalex F85 (softening point 85℃, manufactured by Eastman Chemicals), Kristalex F100 (softening point 100℃, manufactured by Eastman Chemicals), and Kristalex F115 (softening point 115℃, manufactured by Eastman Chemicals).

[0065] <Softener>

[0066] The plasticizer is compatible with the soft segments that constitute the hydrogenated block copolymer. The plasticizer is liquid at 23°C.

[0067] Examples of plasticizers include aliphatic hydrocarbons such as polybutene compounds, polyisobutylene compounds, and polyisoprene compounds. More specifically, examples include commercially available plasticizers such as JXTG Energy's polybutene LV-7, LV-50, LV-100, HV-15, HV-35, HV-50, HV-100, HV-300, HV-1900, and SV-7000 (all manufactured by JXTG Energy) as polybutene compounds, Tetrax 3T, 4T, 5T, and 6T, Himol 4H, 5H, 5.5H, and 6H (all manufactured by JXTG ENERGY) as polyisobutylene compounds, and Kuraprene LIR-290 (manufactured by Kuraprene) as a polyisoprene compound.

[0068] 1-3. Conductive polymers

[0069] The conductive polymer of the present invention imparts conductivity to the adhesive composition, which contributes to the antistatic properties of the adhesive composition.

[0070] There are no particular limitations as long as the conductive polymer is an organic polymer whose main chain is composed of a π-conjugated system and has the effects of the present invention. Examples include polypyrrole-based conductive polymers, polythiophene-based conductive polymers, polyacetylene-based conductive polymers, polyphenylene-based conductive polymers, polyphenylene oxide-based conductive polymers, polyaniline-based conductive polymers, poly(phenylene oxide)-based conductive polymers, polythiophene oxide-based conductive polymers, and copolymers thereof. From the viewpoint of stability in air, polypyrrole-based conductive polymers, polythiophene-based polymers, and polyaniline-based conductive polymers are preferred. From the viewpoint of transparency, polythiophene-based conductive polymers are preferred.

[0071] The conductive polymer preferably has at least one of the structural units represented by chemical formula (1) or (2). The π-conjugated polymer system included in the conductive polymer is characterized by having R... 1 This makes the skeleton easily deformable, improving its flexibility. Therefore, it exhibits good dispersibility in solvents or adhesives, and compared to other π-conjugated polymers, it is most effective in improving the conductivity of adhesive compositions.

[0072] The amount of the conductive polymer in the adhesive composition is preferably 0.01 to 35 parts by weight relative to 100 parts by weight of the adhesive, more preferably 0.05 to 30 parts by weight, and even more preferably 0.5 to 20 parts by weight. Specifically, this amount can be, for example, 0.01, 0.05, 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 20, 25, 30, or 35 parts by weight, or within any range between the two values ​​exemplified herein.

[0073] When R 1 When silicone groups are included, the amount of conductive polymer incorporated is preferably 0.01 to 20 parts by weight, more preferably 0.01 to 10 parts by weight, relative to 100 parts by weight of the adhesive. 1 In this process, the ratio of the silicone-based portion is adjusted so that both dispersibility and conductivity can be achieved even with a small amount of compound.

[0074] When R 1 When alkyl groups are included, the amount of conductive polymer incorporated is preferably 0.01 to 35 parts by mass relative to 100 parts by mass of the adhesive, more preferably 0.1 parts by mass or more.

[0075]

Chemistry 1

[0076]

[0077]

Chemistry 2

[0078]

[0079] R 1 R represents an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an oxidized alkenyl group having 1 to 12 carbon atoms with repeating units of 1 to 50, a phenyl group that may have substituents, a heterocyclic group that may have substituents, or a fused-ring group that may have substituents. 2 R represents oxygen or sulfur atoms respectively. 3 These represent either hydrogen atoms or organic groups, respectively. A － Anions derived from dopants. n is 2 or higher and 300 or lower.

[0080] The aforementioned alkyl groups with 1 to 12 carbon atoms can be straight-chain, branched, cyclic, etc. For example, they can be 1 to 8 carbon atoms, 1 to 6 carbon atoms, 1 to 4 carbon atoms, etc. Specifically, examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, cyclopentyl, cyclohexyl, borneol, isoborneol, dicyclopentyl, adamantyl, etc.

[0081] As an alkoxy group having 1 to 12 carbon atoms, it can be linear, branched, cyclic, etc., for example, having 1 to 8 carbon atoms, 1 to 6 carbon atoms, 1 to 4 carbon atoms, etc.

[0082] Examples of oxidized alkenyl groups with 1 to 12 carbon atoms include those with 1 to 8 carbon atoms, those with 1 to 6 carbon atoms, and those with 1 to 4 carbon atoms.

[0083] Examples of heterocyclic groups derived from the following heterocyclic compounds include: thiophene ring, furan ring, thiophene ring, oxazole ring, pyrrole ring, pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring, triazine ring, oxadiazole ring, triazole ring, imidazole ring, pyrazole ring, thiazole ring, indole ring, benzimidazole ring, benzothiazole ring, benzoxazole ring, quinoxaline ring, quinazoline ring, phthalazine ring, thiophene-thiophene ring, carbazole ring, and azacarbazole ring (indicating that any one or more carbon atoms constituting the carbazole ring are replaced by nitrogen atoms). Heterocyclic rings), dibenzothiophene rings, dibenzofuran rings, dibenzothiophene rings, rings formed by replacing one or more carbon atoms in the benzothiophene or dibenzofuran ring with nitrogen atoms, benzodifuran rings, benzodithiophene rings, acridine rings, benzoquinoline rings, phenazine rings, phenanthridine rings, phenanthroline rings, cyclamate rings, quinoline rings, tepenizine rings, quinindoline rings, tribenzodithiazine rings, tribenzodioxazine rings, phenanthridine rings (nthrazine) ring, atrazine ring, naphthalene intercalation diazabenzene ring, naphthofuran ring, naphthothiophene ring, naphthodifuran ring, naphthodithiophene ring, anthraquinone ring, anthraquinone difuran ring, anthraquinone dithiophene ring, anthraquinone dithiophene ring, thiaphene ring, phenthiaquinone ring, dibenzocarbazole ring, indolecarbazole ring, dithienylbenzene ring, epoxy ring, aziridine ring, thiapropyl ring, oxacyclobutane ring, aziridine ring, thiacyclobutane ring, tetrahydrofuran ring, dioxacyclopentane ring, pyrrolidine ring, pyrazolidine ring, imidazoline ring Oxazolidine ring, tetrahydrothiophene ring, sulfolane ring, thiazolidinyl ring, ε-caprolactone ring, ε-caprolactam ring, piperidine ring, hexahydropyridazine ring, hexahydropyrimidine ring, piperazine ring, morpholine ring, tetrahydropyran ring, 1,3-dioxane ring, 1,4-dioxane ring, trioxane ring, tetrahydrothiophene ring, thiomorpholine ring, thiomorpholine-1,1-dioxide ring, pyranose ring, diazabicyclo[2,2,2]-octyl ring, phenothiazine ring, phenothiazine ring, dioxin ring, thioxanthate ring, phenothiazine ring.

[0084] Examples of fused ring groups include naphthalene ring, azurite ring, anthracene ring, phenanthrene ring, pyrene ring, trehalose ring, naphthonaphthalene ring, triphenylene ring, acenaphthene ring, halobenzene ring, fluorene ring, fluoranthene ring, pentanebenzene ring, perylene ring, pentofen ring, bainene ring, and pinanthrone ring.

[0085] Examples of substituents include alkyl groups with 1 to 12 carbon atoms, alkyl ether groups with 1 to 12 carbon atoms, alkoxy groups with 1 to 12 carbon atoms, oxidized alkenyl groups with 1 to 12 carbon atoms, aromatic groups, hydroxyl groups, carboxyl groups, halogens such as fluorine, chlorine, bromine, and iodine, aldehyde groups, amino groups, and cycloalkyl groups with 3 to 8 carbon atoms, with hydroxyl and carboxyl groups being preferred.

[0086] R 1Preferably, it comprises at least one of an alkyl group that may have substituents and a silicone group, and more preferably, it comprises a silicone group. Because the silicone group has a low free energy, if R... 1 If silicone groups are included, conductive polymers tend to aggregate near the surface of the adhesive composition, making the surface resistance easier to reduce.

[0087] Alkyl groups can be categorized as having 1 to 12 carbon atoms. The alkyl groups described above can be cited as examples of such alkyl groups.

[0088] The silicone group is a group in which a siloxane, whose main backbone is composed of alternating silicon and oxygen bonds, is bonded to an organic group. The organic group is preferably an aromatic group or an alkyl group with 1 to 12 carbon atoms, and methyl is preferred.

[0089] R 1 Preferably, it has an ester bond. As R 1 The ester bond can include carboxylic ester bonds, phosphate ester bonds, sulfonate ester bonds, etc., with carboxylic ester bonds being preferred. When R 1 The presence of unesterified acid groups (such as carboxyl groups) in conductive polymers results in excessively high polarity, leading to reduced cohesiveness of the conductive polymers in the adhesive composition. Esterification of the acid groups reduces polarity and improves dispersibility in the adhesive composition.

[0090] R 1 Preferably, it has a structure represented by chemical formula (3).

[0091]

Transformation 3

[0092]

[0093] (In chemical formula (3), * represents the bonding part, R) 4 For direct bonding or organic groups, R 5 It contains at least one of an organic group and a silicone group.

[0094] As R 3 R 4 or R 5 Organic groups that may have substituents include alkyl groups with 1 to 12 carbon atoms, alkyl ether groups with 1 to 12 carbon atoms, alkoxy groups with 1 to 12 carbon atoms, oxidized alkenyl groups with 1 to 12 carbon atoms, aromatic groups, heterocyclic groups, etc. R 5 Preferably, a hydroxyl group is present at the β-position.

[0095] The alkyl, alkoxy, oxidized alkenyl, and heterocyclic groups are explained as described above.

[0096] The aforementioned alkyl ether groups with 1 to 12 carbon atoms can be linear, branched, cyclic, etc., for example, with 1 to 8 carbon atoms, 1 to 6 carbon atoms, 1 to 4 carbon atoms, etc.

[0097] In addition to phenyl and benzyl groups, various fused-ring groups can be listed as aromatic groups. Examples of fused-ring groups include naphthalene rings, azurite rings, anthracene rings, phenanthrene rings, pyrene rings, trehalose rings, naphthonaphthalene rings, triphenylene rings, acenaphthene rings, halobenzene rings, fluorene rings, fluoranthene rings, pentanebenzene rings, perylene rings, pentofen rings, styrax rings, and pinanthrone rings.

[0098] As dopants, any compound that can impart conductivity to π-conjugated polymers and become a monoanion can be listed. Examples of dopants include vinyl sulfonic acid, methanesulfonic acid, p-toluenesulfonic acid, dodecyl sulfonic acid, dodecylbenzene sulfonic acid, di(2-ethylhexyl)sulfosuccinic acid, tetrafluoroboric acid, trifluoroacetic acid, hexafluorophosphate, trifluoromethanesulfonylimide, naphthalene sulfonic acid, and other monovalent acids or their alkali metal salts. Using a dopant that becomes a monoanion readily improves the conductivity of the conductive polymer. The structure of the dopant affects the dispersibility in the adhesive composition; however, from the viewpoint of balancing conductivity and dispersibility, dodecylbenzene sulfonic acid is preferred.

[0099] The number of structural units (1) and (2) in the conductive polymer is not particularly limited, but is preferably 2 or more and 300 or less. Specifically, for example, it is 2, 5, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200 or 300, or it can be within the range of any two values ​​exemplified herein.

[0100] The content ratio of structural units (1) and (2) contained in the conductive polymer can be adjusted by the ratio of the amount of thiophene derivative to aldehyde expressed in chemical formula (4). The molar ratio of the amount of thiophene derivative to aldehyde (thiophene derivative / aldehyde) is, for example, 1 / 1, 2 / 1, 3 / 1, 4 / 1, 5 / 1, etc., and can be within any two of these values, but from the viewpoint of balancing solubility and conductivity, a ratio of 1 / 1 to 4 / 1 is preferred, and a ratio of 1 / 1 to 2 / 1 is more preferred.

[0101]

Chemistry 4

[0102]

[0103] In chemical formula (4), R 2 and R 3 R of chemical formulas (1) and (2) respectively 2 and R 3 The same definition applies.

[0104] There are no particular limitations on the method for synthesizing conductive polymers. For example, they can be obtained by adding dopants and oxidants to thiophene derivatives and aldehydes, and then polymerizing them in a solvent under an inert gas atmosphere by heating and stirring. Furthermore, decomposition promoters of oxidants can also be added.

[0105] Aldehydes can be those with acid groups or those with ester bonds. Examples of aldehydes with acid groups include phthalic acid. Examples of aldehydes with ester bonds include aldehydes that have been esterified from acid groups. Esterification can be achieved, for example, by reacting the acid group with the epoxy group of an epoxy-containing compound (e.g., an epoxide, a monoterminated epoxysiloxane). When using aldehydes with acid groups, the conductivity tends to increase due to stronger molecular interactions.

[0106] The molar ratio of the dopant to the thiophene derivative (dopant / thiophene derivative) is, for example, 0.01 to 0.5, preferably 0.1 to 0.5. Specifically, this molar ratio is, for example, 0.01, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, or within any range of two values ​​exemplified herein. If this molar ratio is too small, the conductivity of the conductive polymer may become too low.

[0107] As an oxidant, there are no particular limitations; any oxidant capable of undergoing polymerization is acceptable. Examples include ammonium peroxydisulfate, potassium peroxydisulfate, sodium peroxydisulfate, ferric chloride (III), ferric sulfate (III), ferric hydroxide (III), ferric tetrafluoroborate (III), ferric (III) hexafluorophosphate, copper sulfate (II), copper chloride (II), copper tetrafluoroborate (II), copper hexafluorophosphate (II), as well as organic peroxides such as ammonium oxodisulfate, benzoyl peroxide, and lauroyl peroxide.

[0108] As a solvent, there are no particular limitations; any solvent capable of enabling the reaction between heterocyclic compounds and aldehyde derivatives is acceptable. Examples include alcohol solvents such as γ-butyrolactone, propylene carbonate, ethylene carbonate, acetonitrile, tert-butyl methyl ether, ethyl acetate, benzene, heptane, water, methanol, ethanol, isopropanol, and butanol; ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; diol solvents such as methyl cellosolve and ethyl cellosolve; and lactic acid solvents such as methyl lactate and ethyl lactate. Considering the efficiency of the oxidant, aprotic solvents are preferred.

[0109] 1-4. Solvents

[0110] The adhesive composition of the present invention may contain a solvent. The solvent is not particularly limited as long as it can dissolve or disperse the conductive polymer, but organic solvents are preferred. Examples of organic solvents include, for example, alcohol-based solvents such as methanol, ethanol, isopropanol, and butanol; ketone-based solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclopentanone; diol-based solvents such as methyl cellosolve, ethyl cellosolve, propylene glycol methyl ether, and propylene glycol ethyl ether; lactic acid-based solvents such as methyl lactate and ethyl lactate; toluene, anisole, ethyl acetate, propylene carbonate, γ-butyrolactone, toluene, isopropanol, ethylene glycol, dimethyl sulfone, methanol, and benzyl alcohol; particularly preferred are propylene carbonate, γ-butyrolactone, methyl ethyl ketone, toluene, anisole, isopropanol, ethylene glycol, dimethyl sulfone, methanol, and benzyl alcohol. Multiple organic solvents may be used in combination, and the solvent may be the same as or different from that used in the synthesis of the conductive polymer.

[0111] In order to stably disperse conductive polymers in water, an excess of sulfonic acid that has no effect on doping is required. However, when the conductive polymer composition contains organic solvents, even with a small amount of excess sulfonic acid, the conductive polymers can be stably dissolved or dispersed in the organic solvents.

[0112] In conductive polymer compositions, there are no particular limitations on the non-volatile components of the organic solvent, for example, ranging from 0.1% by mass to 20.0% by mass. Specifically, this can be 0.1, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 5.0, 10.0, 15.0, or 20.0% by mass, or within any range between any two values ​​exemplified herein.

[0113] In addition to the organic solvents mentioned above, the solvent for the conductive polymer composition may also include water, but from the viewpoint of substrate adhesion, it is preferable that the water content is 50% or less relative to the solvent, more preferably 10% or less.

[0114] 1-5. Other ingredients

[0115] The adhesive composition of the present invention may further include components such as silane coupling agents, silicone resins, platinum catalysts, and photopolymerization initiators. Furthermore, the adhesive composition of the present invention may be appropriately combined with solvents, tackifying resins, sensitizers, fillers, flame retardants, fillers, organopolysiloxane compounds, ionic compounds, plasticizers, curing co-catalysts, dispersants, pigments / dyes, viscosity modifiers, lubricants, anti-settling agents, rheology control agents, ultraviolet absorbers, lightfastness imparting agents, antioxidants, water-repellent agents, and defoamers.

[0116] [Silane coupling agent]

[0117] Silane coupling agents form chemical bonds with various substrates, improving the adhesion between the substrate and the substrate. They are particularly effective for bonding with glass substrates.

[0118] Examples of silane coupling agents include vinyltrimethoxysilane, vinyltriethoxysilane, and methacryloxypropyltrimethoxysilane, which are silicon compounds containing polymerizable unsaturated groups; 3-epoxypropoxypropyltrimethoxysilane, 3-epoxypropoxypropylmethyldimethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, which are silicon compounds with epoxide structures; 3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, and N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, which are amino-containing silicon compounds; 3-chloropropyltrimethoxysilane; and oligomeric silane coupling agents.

[0119] The amount of silane coupling agent used is typically 0.01 to 0.3 parts by weight, preferably 0.05 to 0.25 parts by weight, relative to 100 parts by weight of the adhesive. Furthermore, one type of silane coupling agent can be used, or two or more types can be used in combination.

[0120] 1-6. Polarizing Thin Films 3

[0121] The polarizing film 3 may have a polarizer 3a or a polarizer protective film 3b. The polarizer 3a is disposed between the adhesive layer 2 and the polarizer protective film 3b.

[0122] As a polarizer 3a, examples include extended films obtained by extending films that contain a polarizing component in films made of polyvinyl alcohol-based resins. Examples of polyvinyl alcohol-based resins include saponified forms of polyvinyl alcohol, polyvinyl formal, polyvinyl acetal, and ethylene-vinyl acetate copolymers. Examples of polarizing components include iodine or dichroic dyes.

[0123] As a polariton protection film 3b, for example, a film made of a thermoplastic resin can be cited. Examples of thermoplastic resins include cellulose resins such as triacetyl cellulose, polyester resins, polyethersulfone resins, polysulfone resins, polycarbonate resins, polyamide resins, polyimide resins, polyolefin resins, (meth)acrylic resins, cyclic polyolefin resins (norbornene resins), polyarylate resins, polystyrene resins, polyvinyl alcohol resins, and mixtures of two or more selected from these resins.

[0124] The thickness of the polarizing film 3 is typically 10–200 μm, preferably 30–100 μm. In this invention, the polarizer protective film 3b formed on the polarizer 3a can be omitted, thus enabling the polarizing film 3 to be made thinner.

[0125] The polarizing film 3 sometimes exhibits the property of easily shrinking under high-temperature conditions. In this case, since the adhesive layer 2 easily shrinks as the polarizing film 3 shrinks, as described above, the technical significance of setting the storage modulus of the adhesive layer 2 at 80°C to a specified range is particularly significant.

[0126] Here, the individual shrinkage rate P(%) of the polarizing film 3 is defined as ((Xp-Yp) / Xp)×100. Xp is the dimension of the polarizing film 3 along its extension axis after it has been placed alone in an environment of 23℃ and 50%RH, and Yp is the dimension of the polarizing film 3 along its extension axis after it has been placed alone in an environment of 80℃ for 72 hours and then cooled in an environment of 23℃ and 50%RH for 10 minutes.

[0127] The individual shrinkage rate P is, for example, 0.01 to 10%, preferably 1 to 8%. Specifically, the individual shrinkage rate P is, for example, 0.01, 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10%, or may be within the range of any two values ​​exemplified herein.

[0128] 1-7. High Temperature Holding Power

[0129] The adhesive polarizing film 1 preferably exhibits excellent holding power at high temperatures. Specifically, when the adhesive surface 1a of the adhesive polarizing film 1 is adhered to a glass plate (preferably an alkali-free glass plate) with an area of ​​10 mm × 10 mm, and a load of 800 g is applied in the shear direction at 80°C, the displacement of the adhesive layer relative to the glass plate from the start of the load application to one hour later is preferably less than 2.0 mm. At this time, as... Figure 2 As shown, when the adhesive polarizing film 1 is attached to the image display element 6, displacement of the adhesive polarizing film 1 from the image display element 6 is suppressed. This displacement is, for example, 0 to 2.0 mm, specifically, for example, 0, 0.5, 1.0, 1.5, 2.0 mm, or within any two values ​​exemplified herein.

[0130] 2. Laminated body for image display device

[0131] like Figure 2 As shown, in one embodiment of the present invention, the image display device laminate 5 is constructed by bonding an adhesive polarizing film 1 to an image display element 6.

[0132] With the release film 4 peeled off to expose the adhesive surface 1a, the adhesive polarizing film 1 can be attached to the image display element 6 in such a way that the adhesive surface 1a contacts the image display element 6.

[0133] The image display element 6 is a component used to display images. The image display element 6 is preferably a component having a glass plate on the surface where the adhesive polarizing film 1 is adhered. The glass plate is preferably a non-polarizing glass plate. Liquid crystal cells can be cited as examples of such image display elements 6.

[0134] The liquid crystal cell is preferably a liquid crystal cell that constitutes an embedded or external touch panel type input / output device. Embedded means that the touch panel function is incorporated into the pixels of the liquid crystal. External means that the touch panel function is incorporated between the color filter substrate and the polarizing film.

[0135] Such methods often result in touch sensor malfunction due to static electricity generated near the cover glass, leading to poor touch performance. Therefore, by using an adhesive composition with low surface resistivity, which combines the conductive polymer of this invention with an adhesive composition, the static electricity generated near the cover glass can be neutralized and dispersed using the adhesive layer, thus suppressing touch issues.

[0136] The thickness of the glass plate is, for example, 0.3 to 3 mm, specifically 0.3, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0 mm, or within any two values ​​listed here.

[0137] The thickness of the image display element 6 is, for example, 0.5 to 6 mm, specifically, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0 mm, or within any two values ​​exemplified here.

[0138] Here, the laminate shrinkage rate of the polarizing film 3 in the laminate 5 is defined as S(%) = ((Xs-Ys) / Xs)×100. Xs is the dimension of the polarizing film 3 in the extension axis direction in the laminate 5 after the laminate 5 is placed in an environment of 23°C and 50%RH, and Ys is the dimension of the polarizing film 3 in the extension axis direction in the laminate 5 after the laminate 5 is placed in an environment of 80°C for 72 hours and then cooled in an environment of 23°C and 50%RH for 10 minutes.

[0139] S is preferably less than 3. That is, it preferably satisfies the following equation (1).

[0140] ((Xs-Ys) / Xs)×100<3···(1)

[0141] At this time, since the shrinkage rate S is not large, the increase in surface resistivity of adhesive layer 2 caused by the shrinkage of polarizing film 3 is suppressed.

[0142] The shrinkage rate S of the laminate is, for example, 0.01 to 2.99, preferably 0.01 to 2.9, and more preferably 0.01 to 2.0. Specifically, the shrinkage rate S is, for example, 0.01, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, or within any range between any two values ​​exemplified herein.

[0143] After placing the laminate 5 in an environment of 23°C and 50% RH, the surface resistivity of the adhesive layer 2 exposed by peeling off the adhesive polarizing film 1 from the laminate 5 is defined as Xr. After placing the laminate 5 in an environment of 80°C for 72 hours, and then cooling it in an environment of 23°C and 50% RH for 10 minutes, the surface resistivity of the adhesive layer 2 exposed by peeling off the adhesive polarizing film 1 from the laminate 5 is defined as Yr. Preferably, both Xr and Yr are less than 1.0 × 10⁻⁶. 12 At this point, at both room temperature and high temperature, a laminate 5 with an adhesive layer 2 having sufficiently low surface resistivity can be obtained.

[0144] Xr and Yr are more preferably less than 5.0 × 10⁻⁶. 11 More preferably less than 1.0 × 10 11 More preferably, it is less than 5.0 × 10 10 More preferably less than 1.0 × 10 10 More preferably, it is less than 5.0 × 10 9 More preferably less than 1.0 × 10 9 .

[0145] Xr and Yr preferably satisfy the following equation (2).

[0146] Yr / Xr<10···(2)

[0147] At this point, the increase in surface resistivity under high-temperature conditions is suppressed. The value of Yr / Xr is, for example, 0.5 to 9.9, preferably 1 to 5. Specifically, this value is, for example, 0.5, 1, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, 9.9, or may be within the range of any two values ​​exemplified herein.

[0148]

Example

[0149] The present invention will be specifically described with reference to the embodiments, but the present invention is not limited to these embodiments.

[0150] 1. Manufacturing of conductive polymers

[0151] Conductive polymers C1 to C5 were manufactured using the method shown below.

[0152] • Manufacturing Example C1 (Manufacturing of Conductive Polymer C1)

[0153] 500 g of propylene carbonate, 3.4 g of 3,4-ethylenedioxythiophene (EDOT), and 3.0 g of dodecylbenzenesulfonic acid (DBS) were added to a 1 L flask and stirred for 0.25 hours. Then, under nitrogen purging, 0.04 g of ferric tri-p-toluenesulfonate (III)(Fe(PTS)3), 1.8 g of phthalic acid (PAA), 6.75 g of benzoyl peroxide, and 100 g of propylene carbonate were added and stirred at 40 °C for 4 hours. Subsequently, 1.25 g of DBS was added and stirred at 60 °C for 2 hours. 30 g of anion exchange resin (LEWATIT MP62WS LANXESS) substituted with propylene carbonate was added and stirred for 24 hours. The anion exchange resin was removed, and the mixture was treated with an ultrasonic homogenizer and modulated with propylene carbonate to obtain a propylene carbonate dispersion (1.0% by mass) mainly containing conductive polymer C1 structural units represented by chemical formula (1).

[0154] R of conductive polymer C1 1 It is represented by chemical formula (5).

[0155]

Transformation 5

[0156]

[0157] • Manufacturing Example C2 (Manufacturing of Conductive Polymer C2)

[0158] 1.2 g of hexane was added to the propylene carbonate dispersion obtained in manufacturing example C1, and the mixture was stirred at 80 °C for 6 hours to allow the carboxyl groups of the conductive polymer to react with the epoxy alkyl groups of the hexane, thus obtaining a dispersion of the alkyl-modified conductive polymer C2.

[0159] R of conductive polymer C2 1 It is represented by chemical formula (6).

[0160]

Transformation 6

[0161]

[0162] • Manufacturing Example C3 (Manufacturing of Conductive Polymer C3)

[0163] The 1.2 g of hexane used for modification in Manufacturing Example C2 was replaced with 56.4 g of a single-terminated epoxy alkyl silicone (Shin-Etsu Chemical Industry Co., Ltd. "X-22-173DX"). Otherwise, a dispersion of conductive polymer C3 was obtained using the same method as in Manufacturing Example C2. Conductive polymer C3 is obtained by reacting the carboxyl group of the unmodified conductive polymer with the epoxy alkyl group of X-22-173DX, thereby modifying it with silicone.

[0164] R of conductive polymer C3 1 It is represented by chemical formula (7).

[0165]

Transformation 7

[0166]

[0167] • Manufacturing example C4 (manufacturing of conductive polymer C4)

[0168] In a 1L flask, 30g of a single-terminal epoxy organosiloxane (Shin-Etsu Chemical Industry X-22-173BX), 1.98g of sodium 2-mercaptoethanesulfonate, 23g of isopropanol, and 0.3g of triethylamine were added and mixed. The mixture was then reacted under reflux for 15 hours. Water was added to the reactants, and the isopropanol was removed by vacuum distillation to obtain an emulsion of acid-modified silicone compound (12.6% non-volatile components).

[0169] Next, in the reaction apparatus, 142.5 g of the emulsion of the acid-modified silicone compound, 1.6 g of concentrated hydrochloric acid, 3.2 g of ethylenedioxythiophene (EDOT), and 0.09 g of ferric sulfate were added and mixed, and stirred at 30°C for 30 minutes. Then, over 1 hour, 5.9 g of ammonium persulfate dissolved in 50 g of deionized water was added dropwise to the mixture. The reaction was then maintained at 30°C for 5 hours. The resulting reaction solution was subjected to solid-liquid separation to obtain a wet product of conductive polymer C4. This wet product was freeze-dried at 0°C for 24 hours to obtain a dry powder of conductive polymer C4. Next, the dry powder of conductive polymer C4 was mixed at a ratio of 1.5% relative to the non-volatile component of methyl ethyl ketone, and processed using a probe-type ultrasonic homogenizer to obtain an organic solvent dispersion of conductive polymer C4.

[0170] • Manufacturing Example C5 (Manufacturing of Conductive Polymer C5)

[0171] In a 2L flask, 50g of sodium ethyl 2-methacrylate sulfonate (2-NaSEMA), 55g of benzyl methacrylate (BzMA), 47g of 2-ethylhexyl methacrylate (2-EHA), 150g of water, and 300g of isopropanol were added. After heating to reflux temperature, 0.7g of azobisisobutyronitrile (AIBN) was added, and the polymerization reaction was carried out under reflux for 18 hours. After the reaction was completed, the mixture was cooled to room temperature to obtain the polymerization solution.

[0172] Next, 500g of hexane was added to the 2L flask containing the above polymerization solution to obtain a mixture. The mixture was then subjected to separation extraction using a separatory funnel to remove impurities from the oil layer. After 1 hour, the aqueous layer after separating 1kg of methanol was extracted to separate the solid component, which was then filtered off. The obtained solid was dried under reduced pressure at 100°C for 24 hours, and then pulverized using a mortar and pestle to obtain a powder of the polymer compound.

[0173] Next, 16.1 g of the aforementioned polymer compound, 200 g of deionized water, and 6 g of 35% hydrochloric acid aqueous solution were weighed and added to a 1 L flask. The mixture was heated and stirred at 60 °C to obtain a homogeneous aqueous solution of the polymer compound. After cooling the aqueous solution, 4.65 g of aniline was weighed and added. The mixture was stirred and dissolved to obtain a homogeneous emulsion. Separately, 30 g of water and 10 g of ammonium persulfate were weighed and mixed. This mixture was added dropwise to the flask containing the emulsion at 0 °C over a period of 2 hours. After the addition was completed, the mixture was brought back to room temperature (25 °C) and stirred for 48 hours.

[0174] After the polymerization solution was filtered, the resulting crystals were redispersed in water and washed, followed by filtration again. The water-containing solid material obtained by repeating the above washing process four times was taken out and dried at 40°C under reduced pressure for 96 hours to obtain a dry powder of conductive polymer C5.

[0175] The dry powder of conductive polymer C5 was mixed with the non-volatile component of methyl ethyl ketone at a ratio of 1.5%, and the mixture was processed using a probe-type ultrasonic homogenizer to obtain an organic solvent dispersion of conductive polymer C5.

[0176] 2. Manufacturing of (meth)acrylic polymers

[0177] • Manufacturing Example A1 (Manufacturing of (Meth)acrylate Polymer A1)

[0178] In a reaction apparatus equipped with a stirrer, reflux cooler, thermometer, and nitrogen inlet, 96.8 parts by mass of butyl acrylate, 0.2 parts by mass of acrylic acid, and 3 parts by mass of 2-hydroxyethyl acrylate were added. Ethyl acetate was then added to bring the monomer concentration to 50% by mass. Next, 0.1 parts by mass of 2,2'-azobisisobutyronitrile (2,2'-azobisisobutyronitrile) was added relative to the total monomer content of 100 parts by mass. Nitrogen was used to replace the air in the reaction vessel, and the mixture was stirred and heated to 60°C for 4 hours. After the reaction was complete, the solution was diluted with ethyl acetate to obtain a solution of (meth)acrylic acid polymer A1 (15% non-volatile components). The weight-average molecular weight (Mw), Mw / Mn ratio, and individual storage modulus of the polymer at 80°C for (meth)acrylic acid polymer A1 are shown in Table 1.

[0179] • Manufacturing Examples A2-A9 (Manufacturing of (Meth)acrylic Polymers A2-A9)

[0180] The monomer composition ratios were changed as shown in Table 1. Otherwise, (meth)acrylic polymers A2 to A9 were polymerized using the same method as in Manufacturing Example A1, and Mw, Mw / Mn, and storage modulus at 80°C were determined using the methods shown below. The results are shown in Table 1.

[0181] Table 1

[0182]

[0183] The abbreviations in the table refer to the following.

[0184] BA: Butyl acrylate

[0185] MEA: 2-Methoxyethyl Acrylate

[0186] MA: Methyl acrylate

[0187] BzA: Benzyl acrylate

[0188] 2EHA: 2-Ethylhexyl acrylate

[0189] AA: Acrylic acid

[0190] 2HEA: 2-Hydroxyethyl acrylate

[0191] <Mw, Mn>

[0192] The weight-average molecular weight (Mw) and number-average molecular weight (Mn) were determined using gel permeation chromatography (GPC) under the following conditions.

[0193] • Measuring apparatus: HLC-8320GPC (manufactured by Tosho Corporation)

[0194] • GPC column structure: The following four columns (all manufactured by Tosho Corporation)

[0195] (1) TSKgel HxL-H (protective column)

[0196] (2) TSKgel GMHxL

[0197] (3) TSKgel GMHxL

[0198] (4) TSKgel G2500HxL

[0199] • Flow rate: 1.0 mL / min

[0200] • Column temperature: 40℃

[0201] • Sample concentration: 1.5% (w / v) (diluted with tetrahydrofuran)

[0202] • Mobile phase solvent: Tetrahydrofuran

[0203] Standard polystyrene conversion

[0204] <80℃ Energy Storage Modulus>

[0205] The energy storage modulus at 80℃ in the table was determined using the following method.

[0206] A test sample (here, a (meth)acrylic polymer) was coated onto a glass-treated polyethylene terephthalate (PET) film with a dried film thickness of 25 μm using a doctor blade at a liquid temperature of 25°C. The film was then dried at 90°C for 3 minutes to obtain an adhesive sheet. Multiple adhesive layers obtained from these adhesive sheets were prepared and stacked to create a 1 mm thick test piece. Using this test piece, the storage modulus at 80°C was measured using an AntonPaar Modular Compact Rheometer MCR300. It should be noted that the measurement frequency was 1 Hz.

[0207] 3. Preparation of adhesive composition

[0208] An adhesive composition for evaluation was prepared by mixing the various components shown in Tables 2 to 5 according to the proportions (parts by mass) shown in Tables 2 to 5. The conductive polymer and the (meth)acrylic polymer were mixed in the state of a dispersion or solution obtained in the above manufacturing example. The proportions of the conductive polymer and the (meth)acrylic polymer indicate the amount of solid components in the dispersion or solution.

[0209] 4. Fabrication of adhesive polarizing films

[0210] On a peeled polyethylene terephthalate (PET) film, the adhesive composition obtained in "3. Preparation of adhesive composition" is applied by a doctor blade at a liquid temperature of 25°C to a dried film thickness of 25 μm. The film is then dried at 90°C for 3 minutes to obtain an adhesive sheet.

[0211] Next, the obtained adhesive sheet was bonded to the polarizing film shown in Tables 2 to 5 in the manner described above, and placed at 23°C / 50%RH for 7 days to obtain the adhesive polarizing film of the Example / Comparative Example.

[0212] Table 2

[0213]

[0214] Table 3

[0215]

[0216] Table 4

[0217]

[0218] Table 5

[0219]

[0220] The specific components and parts listed in the table above are as follows.

[0221] ((meth)acrylic acid polymers)

[0222] • (Meth)acrylic acid polymers A1-A9:

[0142] (conductive polymers) manufactured in manufacturing examples A1-A9

[0223] • Conductive polymers C1 to C5:

[0143] (hydrogenated block copolymer) manufactured in manufacturing examples C1 to C5

[0224] Rubber polymers 1 and 2 are as follows. Mw and storage modulus at 80°C were determined using the method described in "2. Preparation of (meth)acrylic polymers".

[0225] • Rubber-based polymer 1 (a mixture of SEPS50 by mass and SEP50 by mass, hydrogenation rate exceeding 90%, styrene content 15 by mass, Mw: 130,000, energy storage modulus at 80℃: 720 kPa)

[0226] • Rubber-based polymer 2 (a mixture of SEPS50 by mass and SEP50 by mass, hydrogenation rate exceeding 90%, styrene content 20 by mass, Mw: 150,000, energy storage modulus at 80℃: 920 kPa)

[0227] (Tackifying resin)

[0228] FMR-0150 (Aromatic tackifying resin with a softening point of 145℃: manufactured by Mitsui Chemicals)

[0229] TH-130 (a terpene-phenolic tackifying resin with a softening point of 130°C: manufactured by YASUHARA CHEMICAL)

[0230] • FTR-6100 (Aromatic tackifying resin with a softening point of 95°C: manufactured by Mitsui Chemicals)

[0231] (Softener)

[0232] ·LV-100 (Mn500 polybutene: manufactured by ENEOS)

[0233] HV-300 (Mn1400 polybutene: manufactured by ENEOS)

[0234] (Other ingredients)

[0235] • Crosslinking agent: Tosho Co., Ltd.'s "Coronate L"

[0236] • Silane coupling agent: Shin-Etsu Chemical Co., Ltd., "KBM-403"

[0237] • Antioxidant: ADEKASTAB AO-330 (hindered phenolic antioxidant: manufactured by ADEKA)

[0238] (Polarization film)

[0239] Polarizing thin films with the structure shown in Table 6 are used.

[0240] Table 6

[0241] Table 6

[0242]

[0243] The abbreviations for the protective layer components are as follows.

[0244] COP: Cycloolefin polymer

[0245] PMMA: Polymethyl methacrylate

[0246] PET: Polyterephthalic acid

[0247] TAC: Triacetylcellulose

[0248] The individual shrinkage rate of polarized thin films was determined using the following method.

[0249] The polarizing film was cut into 160 mm (MD direction) × 25 mm (TD direction) pieces to prepare test pieces. Each test piece was individually placed at 23°C and 50% RH for 10 minutes, and then the long-side dimension (Xp) was measured. Next, the test pieces were individually placed at 80°C for 72 hours, then cooled at 23°C and 50% RH for 10 minutes, and the long-side dimension (Yp) of the polarizing film was measured.

[0250] Calculate the individual shrinkage rate (((Xp-Yp) / Xp)×100) from the obtained Xp and Yp.

[0251] 5. Fabrication of experimental laminates

[0252] Test pieces were prepared by cutting the adhesive polarizing film into 160mm (MD direction) × 25mm (TD direction) sizes. The PET film was peeled off from these test pieces. Using laminating rollers, the adhesive polarizing film was bonded to one side of a liquid crystal panel with a 2mm thick alkali-free glass substrate, with the adhesive layer in contact with the alkali-free glass substrate. The panel was then placed in an autoclave at 50°C / 5 atmospheres for 20 minutes to create a laminate for testing.

[0253] 6. Evaluation

[0254] Various evaluations were conducted based on the following criteria. The results are shown in Tables 2 to 5.

[0255] As can be seen from the examples and comparative examples, the laminates of the examples have smaller shrinkage rates, Xr, Yr, and Yr / Xr compared to the laminates of the comparative examples, and exhibit excellent heat resistance and durability at 80°C dry.

[0256] <Storage modulus of adhesive layer at 80℃>

[0257] The adhesive composition constituting the adhesive layer was used as the test sample, and the storage modulus of the adhesive layer at 80°C was determined using the method described in "2. Manufacturing of (meth)acrylic polymer".

[0258] <Displacement of adhesive layer at 80°C>

[0259] The adhesive polarizing film was cut into pieces 10 mm wide and 100 mm long. The PET film was peeled off and bonded to the alkali-free glass with an adhesive layer, forming a bonding area of ​​10 mm × 10 mm, to obtain a test piece for measurement.

[0260] The test piece used for the above test was kept in an autoclave adjusted to 50°C / 5 atmospheres for 20 minutes, and then placed in an environment of 23°C and 50% RH for 1 hour. Next, in the chamber BOX of the micro-creep measuring instrument (manufactured by Eiko Seiki Co., Ltd., model name: TA.TX.PLUS), the test piece was cut so that the length of the fixed clamp part was 15 mm.

[0261] The chamber BOX was heated to 80°C and placed at the test temperature for 40 minutes. Under a tensile load of 800g and a tensile time of 1 hour, the adhesive polarizing film of the test piece was stretched in the direction parallel to the bonding surface between the polarizing film and the glass and along the length of the polarizing film. The displacement (μm) of the bonding portion between the glass and the polarizing film of the test piece was measured.

[0262] <Shrinkage rate of laminates>

[0263] The laminate used in the experiment was cooled for 10 minutes at 23°C and 50% RH, and the long-side dimension (Xs) of the polarizing film in the laminate was measured. Then, after placing the laminate at 80°C for 72 hours, it was cooled for 10 minutes at 23°C and 50% RH, and the long-side dimension (Ys) of the polarizing film in the laminate was measured. The shrinkage rate of the laminate (((Xs-Ys) / Xs)×100) was calculated from the obtained Xs and Ys.

[0264] <Surface resistivity>

[0265] The test laminate was cooled for 10 minutes at 23°C and 50% RH. Using a resistivity meter (HirestaUX MCP-HT800, Mitsubishi Chemical Analytical), a voltage of 1000V was applied, and the surface resistivity (Xr) of the adhesive layer exposed after peeling the adhesive polarizing film from the liquid crystal panel at a peel angle of 90° and a peel speed of 300mm / min was measured according to JIS-K-6911.

[0266] Furthermore, after placing the above-mentioned laminate at 80°C for 72 hours, it was cooled at 23°C and 50%RH for 10 minutes. The adhesive polarizing film was then peeled off from the liquid crystal panel at a peeling angle of 90° and a peeling speed of 300 mm / min. In addition, the surface resistivity (Yr) was measured in the same manner as the surface resistivity (Xr).

[0267] <80℃ dry heat resistance and durability>

[0268] The condition of the laminate used in the test was observed by the naked eye after being placed at a dry temperature of 80℃ for 500 hours. The 80℃ dry heat resistance and durability of the laminate were evaluated using the following criteria.

[0269] ○: Wrinkles, foaming, or peeling in the adhesive layer

[0270] △: There are wrinkles in the adhesive layer, but no foaming or peeling.

[0271] ×: Foaming or peeling occurs in the adhesive layer.

Claims

1. An adhesive polarizing film, comprising an adhesive layer and a polarizing film laminated together, wherein, The adhesive layer is formed of an adhesive composition containing an adhesive and a conductive polymer. The energy storage modulus G' of the adhesive layer at 80°C is 20–95 kPa. The conductive polymer has at least one of the structural units represented by chemical formula (1) or (2). 【Chemistry 1】 (1) 【Chemistry 2】 (2) R 1 R represents an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an oxidized alkenyl group having 1 to 12 carbon atoms with repeating units of 1 to 50, a phenyl group that may have substituents, a heterocyclic group that may have substituents, or a fused-ring group that may have substituents. 2 They are oxygen atoms or sulfur atoms, respectively, R 3 They are hydrogen atoms or organic groups, respectively; A － Single anion derived from dopant; n is 2 or more but less than 300.

2. The adhesive polarizing film according to claim 1, wherein, The adhesive is an acrylic adhesive. The acrylic adhesive comprises a (meth)acrylic polymer and a crosslinking agent. The (meth)acrylic polymer is a polymer of monomer mixtures. In the monomer mixture, the content of the first monomer is 0.05-10% by mass, and the content of the second monomer is 51-99.5% by mass. The first monomer is a monomer containing cross-linking functional groups. The second monomer is not the first monomer, but is selected from at least one of the following: alkyl (meth)acrylates with a glass transition temperature of -60 to 20°C in homopolymers, and alkoxyalkyl (meth)acrylates with a glass transition temperature of -60 to 20°C in homopolymers. The weight-average molecular weight of the (meth)acrylic polymer is above 600,000.

3. The adhesive polarizing film according to claim 1, wherein, The adhesive is a rubber-based adhesive. The rubber-based adhesive comprises a hydrogenated block copolymer, a tackifying resin, and a softener. The hydrogenated block copolymer has segments composed of polymer components of aromatic vinyl monomers and segments composed of polymer components of conjugated diene monomers. The softening point of the tackifying resin is above 80°C. The softener is a liquid at 23°C.

4. The adhesive polarizing film according to claim 1, wherein, The conductive polymer's R 1 It contains ester bonds.

5. The adhesive polarizing film according to any one of claims 1 to 3, wherein, The adhesive composition contains a silane coupling agent.

6. The adhesive polarizing film according to any one of claims 1 to 3, wherein, When the adhesive surface of the adhesive polarizing film is pasted onto a glass plate with an area of ​​10mm × 10mm, and a load of 800g is applied in the shear direction at 80°C, the displacement of the adhesive layer relative to the glass plate from the start of the load application to 1 hour later is less than 2.0mm.

7. A laminate for an image display device, comprising an adhesive polarizing film according to any one of claims 1 to 6 bonded to an image display element.

8. The laminate according to claim 7, which satisfies the following formula (1). ((Xs-Ys) / Xs)×100<3・・・(1) Xs is the dimension along the extension axis of the polarizing film in the laminate after the laminate has been placed in an environment of 23°C and 50% RH, and Ys is the dimension along the extension axis of the polarizing film in the laminate after the laminate has been placed in an environment of 80°C for 72 hours and then cooled in an environment of 23°C and 50% RH for 10 minutes.

9. The laminate according to claim 7 or 8, wherein, Both Xr and Yr are less than 1.0 × 10 12 , Xr is the surface resistivity of the adhesive layer exposed after peeling off the adhesive polarizing film from the laminate after placing it in an environment of 23°C and 50%RH. Yr is the surface resistivity of the adhesive layer exposed after peeling off the adhesive polarizing film from the laminate after placing it in an environment of 80°C for 72 hours and then cooling it in an environment of 23°C and 50%RH for 10 minutes.

10. The laminate according to claim 9, which satisfies the following formula (2). Yr / Xr<10・・・(2)

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