JP2010132891A - Adhesive for optical member, optical member having adhesive layer attached thereto and obtained by using the same, and adhesive composition for active energy beam-setting and/or thermosetting optical member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adhesive composition and an adhesive, which have excellent durability, such as excellent antistatic performance, excellent optical laminate adhesion, especially between the polarizing plate and the glass substrate, with no foaming and peeling produced between the adhesive layer and the glass substrate, even under high-temperature and high-humidity conditions, and the capacity to prevent the phenomenon of light leakage caused by contraction of the polarizing film. <P>SOLUTION: Provided is the adhesive for an optical member wherein the adhesive composition [I], containing an acrylic resin (A) having a side-chain oxyalkylene structure, a weight-average molecular weight of 200,000-3,000,000, and a degree of dispersion of 7 or less, and an unsaturated group containing compound (B) is cross-linked by at least one of an active energy beam and/or heat. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an adhesive for optical members, an optical member with an adhesive layer obtained by using the same, and an adhesive composition for active energy rays and / or thermosetting optical members. Specifically, an optical film (polarizing film, retardation film, optical compensation film, brightness enhancement film, etc.) suitably used for an image display device such as a liquid crystal display device, an organic EL display device, and a PDP, for example, a polarizing film, An optical member pressure-sensitive adhesive used for adhesion between an optical laminate coated with a protective film such as a cellulose triacetate film and a glass substrate of a liquid crystal cell, and a pressure-sensitive adhesive layer containing the optical member pressure-sensitive adhesive were formed. The present invention relates to an optical member with an adhesive layer, particularly a polarizing plate with an adhesive layer.

  Conventionally, a polarizing film, for example, a polarizing plate in which both surfaces of a polarizing film such as a polyvinyl alcohol film provided with polarizing properties are coated with a cellulose film, for example, a cellulose triacetate film, is aligned between two glass plates. Is laminated on the surface of the liquid crystal cell sandwiched between the liquid crystal cells to form a liquid crystal display panel. This lamination onto the liquid crystal cell surface is performed by applying an adhesive layer provided on the polarizing plate surface to the liquid crystal cell surface. It is usually done by touching and pressing.

  The pressure-sensitive adhesive layer provided on the surface of the optical member such as the polarizing plate is provided with a separator for the purpose of preventing scratches or dirt, or the surface for the purpose of preventing scratches or dirt generated during processing and transporting processes. Although a protective film or the like is provided, these separators and the surface protective film are not necessary and are peeled and removed when they are bonded to a liquid crystal cell or the like. Static electricity is generated when the separator or the surface protection film is peeled off from such an optical member, and this static electricity causes dust to adhere to the optical member, causes an abnormal display due to disorder of the liquid crystal alignment, and peripheral circuit elements. There is a problem that problems such as electrostatic breakdown occur.

In addition, when an optical member provided with the above-mentioned pressure-sensitive adhesive layer is bonded to a liquid crystal cell, if foreign matter is mixed, damaged, or an adhesion error occurs, it will be peeled off and re-bonded. As described above, static electricity is generated and a problem occurs.
For example, Patent Document 1 discloses a (meth) acrylic copolymer containing 15 to 100 parts by weight of a (meth) acrylic acid alkylene oxide adduct as a monomer component, as a countermeasure for preventing the occurrence of problems caused by the generation of static electricity. An antistatic pressure-sensitive adhesive composition and an antistatic pressure-sensitive adhesive sheet comprising a coalescence and an alkali metal salt have been proposed.
Patent Document 2 contains a (meth) acrylic polymer obtained by copolymerizing 10 to 70% by mass of a (meth) acrylic monomer having an alkylene oxide structure with another monomer, a liquid ion salt, and an isocyanate crosslinking agent. An adhesive composition has been proposed.

JP 2005-314579 A JP 2008-69261 A

  However, the pressure-sensitive adhesive sheet provided with the pressure-sensitive adhesive layer containing the pressure-sensitive adhesive composition disclosed in Patent Documents 1 and 2 is usefully used as a surface protective film, and is assumed to be peeled off after being bonded to an adherend. Therefore, the pressure-sensitive adhesive properties required for the optical member used for permanent adhesion between the optical laminate and the glass substrate are different from each other, and the durability that is important for optical members, particularly polarizing plate applications. The light leakage prevention performance was not considered at all.

  By the way, liquid crystal display panels using polarizing plates are widely used as display devices for personal computers, liquid crystal televisions, car navigation systems, etc., and the use environment has become very harsh. It is required to be excellent in durability even in use, for example, there is no phenomenon such as foaming or peeling between the pressure-sensitive adhesive layer and the glass plate even under a severe environment such as high temperature and high humidity, In a high-temperature, high-humidity environment, the polarizing film contracts, whereas the adhesive layer cannot follow the contraction of the polarizing film, and light leaks from the peripheral edge of the liquid crystal display panel. It is required that there is no so-called light leakage phenomenon.

  Therefore, in the present invention, under such a background, the antistatic performance is excellent, and further, even under high temperature and high humidity conditions, the optical laminate, particularly, the adhesive property between the polarizing plate and the glass substrate is excellent, and the pressure-sensitive adhesive. A pressure-sensitive adhesive composition and a pressure-sensitive adhesive, particularly an optical member, which do not cause foaming or peeling between the layer and the glass substrate and can prevent light leakage caused by contraction of the polarizing film. It is intended to provide a pressure-sensitive adhesive composition, a pressure-sensitive adhesive for optical members, and an optical member with a pressure-sensitive adhesive layer obtained using the same.

  However, as a result of intensive studies in view of such circumstances, the present inventors, as a result, in the pressure-sensitive adhesive composition containing an acrylic resin and an unsaturated group-containing compound, as an acrylic resin, a specific structure oxyalkylene structure in the side chain. An optical member pressure-sensitive adhesive obtained from a pressure-sensitive adhesive composition containing such an acrylic resin by using one having a weight average molecular weight of 200,000 to 3,000,000 and a dispersity of 7 or less. The agent has been found to be excellent in balance between antistatic performance and durability, and has led to the completion of the present invention.

That is, the gist of the present invention is that an acrylic resin (A) having an oxyalkylene structure in the side chain, a weight average molecular weight of 200,000 to 3,000,000 and a dispersity of 7 or less, and an unsaturated group-containing compound (B ) -Containing pressure-sensitive adhesive composition [I] is a pressure-sensitive adhesive for optical members that is crosslinked by at least one of active energy rays and heat.
In addition, the dispersion degree of the copolymer containing a conventionally well-known oxyalkylene chain containing (meth) acrylic-type monomer is 10 or more normally.

Here, X is an alkylene group, Y is an alkyl group, a phenyl group, R ₁ is a hydrogen atom or a methyl group, and n is an integer of 1 or more.

  The present invention also provides an optical member with a pressure-sensitive adhesive layer obtained by laminating the pressure-sensitive adhesive for optical members on an optical member, and a pressure-sensitive adhesive composition for active energy rays and / or thermosetting optical members.

  The pressure-sensitive adhesive for optical members of the present invention has a good balance between pressure-sensitive adhesive properties and antistatic performance, and also has excellent adhesion between an optical laminate, particularly a polarizing plate and a glass substrate, even under high temperature and high humidity conditions. It is possible to obtain a liquid crystal display panel having excellent durability such that foaming or peeling does not occur between the agent layer and the glass substrate, and a light leakage phenomenon caused by contraction of the polarizing film can be prevented.

Hereinafter, although it demonstrates in detail about the structure of this invention, these show an example of a desirable embodiment, and this invention is not limited to these embodiment.
In the present invention, (meth) acryl means acryl or methacryl, (meth) acryloyl means acryloyl or methacryloyl, and (meth) acrylate means acrylate or methacrylate.

First, the pressure-sensitive adhesive composition [I] of the present invention will be described.
The pressure-sensitive adhesive composition [I] of the present invention contains an acrylic resin (A) having an oxyalkylene structure in the side chain, a weight average molecular weight of 200,000 to 3,000,000 and a dispersity of 7 or less (hereinafter simply “ Acrylic resin (A) ”), and an unsaturated group-containing compound (B).

  The acrylic resin (A) in the present invention is not limited as long as it contains an oxyalkylene structure in the side chain. For example, a method of copolymerizing a monomer containing an oxyalkylene structure, an acrylic resin containing a functional group Examples thereof include those produced by a method of reacting (post-modifying) a compound having an oxyalkylene structure with a functional group.

  Among these, the oxyalkylene structure-containing (meth) acrylic monomer (a1) represented by the following general formula (1) (hereinafter, simply referred to as “oxyalkylene structure-containing (meth) acrylic monomer (a1)”) .) Is an essential component and is preferably obtained by a method of copolymerizing with other copolymerization components from the viewpoint of efficient production and easy expansion of variations in the structure of the acrylic resin.

Here, X is an alkylene group, Y is an alkyl group or a phenyl group, R ₁ is a hydrogen atom or a methyl group, and n is an integer of 1 or more.

  X in the general formula (1) is an alkylene group, among which an alkylene group having 1 to 10 carbon atoms is preferable, and in particular, an alkylene group having 1 to 4 carbon atoms such as an ethylene group, a propylene group, or a tetramethylene group. And ethylene group is particularly preferable. In the case where n is a polyoxyalkylene structure moiety having 2 or more, a homopolymer having the same oxyalkylene structure may be used, or different oxyalkylene structures may be copolymerized randomly or in a block form.

  In the above general formula (1), Y is an alkyl group or a phenyl group, but an alkyl group is usually preferred. The carbon number of the alkyl group is specifically 1 to 15, preferably 1 to 10, particularly preferably 1 to 5. Among these, typically, a methyl group and an ethyl group are exemplified.

R ₁ in the general formula (1) is a hydrogen atom or a methyl group.

  In the general formula (1), n is an integer of 1 or more, preferably 1 to 10, particularly preferably 1 to 2, and further preferably 1. If the value of n is too large, the moisture and heat resistance of the acrylic resin tends to decrease, and n is preferably small from the viewpoint of easy production of an acrylic resin among the raw materials that can be procured.

  The weight average molecular weight of the oxyalkylene structure-containing (meth) acrylic monomer (a1) represented by the general formula (1) is usually preferably 100 to 20000, particularly preferably 110 to 5000, and more preferably 120 to 1000. If the weight average molecular weight is too large, the crystallinity becomes high and handling tends to be difficult, or impurities in the raw material increase, and the production of the acrylic resin (A) tends to be difficult.

  As the oxyalkylene structure-containing (meth) acrylic monomer (a1) satisfying the general formula (1), specifically, the following compounds can be exemplified.

  When Y in the general formula (1) is an alkyl group, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, 2-butoxyethyl ( (Meth) acrylate, 2-butoxydiethylene glycol (meth) acrylate, methoxydiethylene glycol (meth) acrylate, methoxytriethylene glycol (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, methoxydipropylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) ) Acrylate, octoxy polyethylene glycol-polypropylene glycol-mono (meth) acrylate, lauroxy polyethylene glycol mono (meth) acrylate, B carboxymethyl polyethylene glycol mono (meth) acrylate aliphatic of (meth) acrylic acid ester.

  When Y in the general formula (1) is a phenyl group, 2-phenoxyethyl (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, phenoxypolyethylene glycol-polypropylene glycol- (meth) acrylate, nonylphenol ethylene oxide Examples thereof include aromatic (meth) acrylic acid esters such as adduct (meth) acrylate.

  Among these oxyalkylene structure-containing (meth) acrylic monomers (a1), aliphatic (meth) acrylic acid esters are preferably used from the viewpoint of excellent durability, and particularly preferably an oxyethylene structure-containing aliphatic ( A meth) acrylic acid ester is used, and more preferably, methoxyethyl acrylate is used in that a high molecular weight product can be efficiently produced.

  The oxyalkylene structure-containing (meth) acrylic monomer (a1) is preferably contained as a copolymerization component of the acrylic resin (A) in an amount of 20 to 90% by weight, particularly preferably 25%. -80% by weight, more preferably 30-60% by weight, particularly preferably 40-50% by weight. If the content of the oxyalkylene structure-containing (meth) acrylic monomer (a1) is too large, the storage stability of the acrylic resin tends to be inferior, and if it is too small, the antistatic performance tends to be insufficient.

  As a copolymerization component to be copolymerized with the oxyalkylene structure-containing (meth) acrylic monomer (a1), other than the (meth) acrylic acid ester monomer (a2) and, if necessary, the (meth) acrylic monomer (a1) And a functional group-containing monomer (a3) (hereinafter sometimes simply referred to as “functional group-containing monomer (a3)”) and other copolymerizable monomers (a4).

  Examples of the (meth) acrylic acid ester monomer (a2) include (meth) acrylic acid alkyl esters and (meth) acrylic acid phenyl esters. About this (meth) acrylic acid alkyl ester, it is preferable that carbon number of an alkyl group is 1-12 normally, especially 1-8, Furthermore, it is preferable that it is 4-8, Specifically, methyl (meth) acrylate , Ethyl (meth) acrylate, n-butyl (meth) acrylate, iso-butyl (meth) acrylate, tert-butyl (meth) acrylate, n-propyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (Meth) acrylate, n-octyl (meth) acrylate, isodecyl (meth) acrylate, lauryl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, etc. Can be mentioned. Other (meth) acrylic acid ester monomers include tetrahydrofurfuryl (meth) acrylate, benzyl (meth) acrylate, and the like. These can be used alone or in combination of two or more.

  Among such (meth) acrylic acid ester monomers (a2), n-butyl (meth) acrylate and 2-ethylhexyl (meth) acrylate are preferable in terms of copolymerizability, adhesive properties, ease of handling, and availability of raw materials. N-butyl (meth) acrylate is preferably used from the viewpoint of excellent antistatic performance.

  Examples of the functional group-containing monomer (a3) include a hydroxyl group-containing monomer, a carboxyl group-containing monomer, a glycidyl group-containing monomer, an amide group-containing monomer, an amino group-containing monomer, a nitrogen-containing monomer, and a sulfonic acid group-containing monomer. , Alone or in combination of two or more.

  Examples of the hydroxyl group-containing monomer include 2-hydroxyethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 5-hydroxypentyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl ( Acrylic acid hydroxyalkyl esters such as (meth) acrylate, 10-hydroxydecyl (meth) acrylate, (4-hydroxymethylcyclohexyl) methyl acrylate, polyethylene glycol derivatives such as diethylene glycol (meth) acrylate and polyethylene glycol mono (meth) acrylate , Polypropylene glycol derivatives such as polypropylene glycol mono (meth) acrylate, polyethylene glycol-polypropylene glycol-mono (meth) Oxyalkylene-modified monomers such as acrylate, poly (ethylene glycol-tetramethylene glycol) mono (meth) acrylate, poly (propylene glycol-tetramethylene glycol) mono (meth) acrylate, and first grade such as N-hydroxyethyl (meth) acrylamide Hydroxyl group-containing monomer; secondary hydroxyl group-containing monomer such as 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate; 2,2-dimethyl-2- And tertiary hydroxyl group-containing monomers such as hydroxyethyl (meth) acrylate.

  Examples of the carboxyl group-containing monomer include Michael addition of acrylic acid, methacrylic acid, crotonic acid, maleic acid, maleic anhydride, itaconic acid, fumaric acid, acrylamide N-glycolic acid, cinnamic acid, and (meth) acrylic acid. (Eg, acrylic acid dimer, methacrylic acid dimer, acrylic acid trimer, methacrylic acid trimer, acrylic acid tetramer, methacrylic acid tetramer, etc.), 2- (meth) acryloyloxyethyl dicarboxylic acid monoester (eg, 2-acryloyloxyethyl) Succinic acid monoester, 2-methacryloyloxyethyl succinic acid monoester, 2-acryloyloxyethyl phthalic acid monoester, 2-methacryloyloxyethyl phthalic acid monoester, 2-acryloyloxyethyl hexahi Rofutaru acid monoester, 2-methacryloyloxyethyl hexahydrophthalic acid mono ester) and the like.

  Examples of the glycidyl group-containing monomer include glycidyl (meth) acrylate and allyl glycidyl ether.

Examples of the amide group-containing monomer include acrylamide, methacrylamide, N- (n-butoxyalkyl) acrylamide, N- (n-butoxyalkyl) methacrylamide, N, N-dimethyl (meth) acrylamide, N, N- Examples thereof include amide group-containing monomers such as diethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, acrylamide-3-methylbutylmethylamine, dimethylaminoalkylacrylamide, and dimethylaminoalkylmethacrylamide.
Examples of the amino group-containing monomer include amino group-containing monomers such as dimethylaminoethyl (meth) acrylate and diethylaminoethyl (meth) acrylate.

  Examples of the nitrogen-containing monomer include acryloylmorpholine.

  Examples of the sulfonic acid group-containing monomer include olefin sulfonic acids such as ethylene sulfonic acid, allyl sulfonic acid, and methallyl sulfonic acid, 2-acrylamido-2-methylpropane sulfonic acid, styrene sulfonic acid, and salts thereof. .

  Among such functional group-containing monomers (a3), a hydroxyl group-containing monomer, a carboxyl group-containing monomer, a glycidyl group-containing monomer, an amide group-containing monomer, and a nitrogen-containing monomer are preferably used, and further, a hydroxyl group-containing monomer and a carboxyl group-containing monomer are used. In particular, it is preferably used in terms of excellent peel properties, durability, and antistatic performance.

  Examples of other copolymerizable monomers (a4) include acrylonitrile, methacrylonitrile, styrene, α-methylstyrene, vinyl acetate, vinyl propionate, vinyl stearate, vinyl chloride, vinylidene chloride, alkyl vinyl ether, vinyl toluene, Examples include vinyl pyridine, vinyl pyrrolidone, itaconic acid dialkyl ester, fumaric acid dialkyl ester, allyl alcohol, acrylic chloride, methyl vinyl ketone, N-acrylamidomethyltrimethylammonium chloride, allyltrimethylammonium chloride, and dimethylallyl vinylketone.

  As a content ratio of polymerization components other than the oxyalkylene structure-containing (meth) acrylic monomer (a1), the (meth) acrylic acid ester monomer (a2) is preferably 10 to 80% by weight, particularly preferably 20 to 75% by weight. %, More preferably 40 to 70% by weight, and the functional group-containing monomer (a3) is preferably 0 to 40% by weight, more preferably 0.5 to 30% by weight, particularly preferably 3.5 to 20% by weight. The amount of the other copolymerizable monomer (a4) is preferably 0 to 50% by weight, more preferably 0 to 40% by weight, and particularly preferably 0 to 30% by weight.

  For the purpose of increasing the molecular weight, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate A compound having two or more ethylenically unsaturated groups such as divinylbenzene can also be used in combination.

  In the present invention, the acrylic resin (A) is produced by polymerizing the monomer components (a1) to (a4) described above, and such polymerization can be performed by a conventionally known method. For example, the oxyalkylene structure-containing (meth) acrylic monomer (a1), (meth) acrylic acid ester monomer (a2), functional group-containing monomer (a3), other copolymerizable monomer (a4) in an organic solvent. ) And other polymerization monomers and polymerization initiators (azobisisobutyronitrile, azobisisovaleronitrile, benzoyl peroxide, etc.) are mixed or dropped and polymerized at reflux or at 50 to 90 ° C. for 2 to 20 hours. Can be mentioned.

  The weight average molecular weight of the acrylic resin (A) needs to be 200,000 to 3,000,000, preferably 700,000 to 2,500,000, particularly preferably 1,000,000 to 2,200,000, particularly preferably 1,200,000 to 2,000,000. 2 million. If the weight average molecular weight is too small, sufficient agglomeration force will not be obtained even by irradiation with active energy rays described later, and the durability tends to decrease. This is an undesirable tendency.

  Further, the dispersity (weight average molecular weight / number average molecular weight) of the acrylic resin (A) in the present invention needs to be 7 or less, preferably 5.5 or less, particularly preferably 4.5 or less, Particularly preferred is 3.5 or less. When the dispersity exceeds the upper limit, the durability performance of the pressure-sensitive adhesive layer, such as heat resistance and light leakage, is inferior. In order to adjust the degree of dispersion to 7 or less, the reaction temperature can be lowered, the reaction time can be shortened, and the like. Further, the lower limit of the dispersity is usually 2 from the viewpoint of production limit.

  Further, the glass transition temperature of the acrylic resin (A) is not generally specified, but is preferably −80 to −20 ° C., particularly preferably −75 to −25 ° C., more preferably −60 to −30 ° C., and the glass transition temperature. If it is too high, tack tends to be insufficient, and if it is too low, heat resistance tends to be poor.

In addition, said weight average molecular weight is a weight average molecular weight by standard polystyrene molecular weight conversion, and it is a column in high performance liquid chromatography (The Japan Waters company "Waters 2695 (main body)" and "Waters 2414 (detector)"). : Shodex GPC KF-806L (exclusion limit molecular weight: 2 × 10 ⁷ , separation range: 100 to 2 × 10 ⁷ , theoretical plate number: 10,000 plates / piece, filler material: styrene-divinylbenzene copolymer, filler The particle size is 10 μm), and the degree of dispersion is determined from the weight average molecular weight and the number average molecular weight. The glass transition temperature is calculated from the Fox equation.

  The unsaturated group-containing compound (B) used in the present invention may be a monofunctional unsaturated group-containing compound having one unsaturated group in one molecule, or two or more in one molecule. A polyfunctional unsaturated group-containing compound having an unsaturated group may be used, but preferably an unsaturated group-containing compound having two or more unsaturated groups, more preferably an unsaturated group-containing compound having three or more unsaturated groups. A saturated group-containing compound is preferred from the viewpoint of curability during irradiation with active energy rays.

The unsaturated group-containing compound (B) is preferably a compound containing a polymerizable unsaturated group. For example, a urethane (meth) acrylate compound, an epoxy (meth) acrylate compound, a polyester (meth) An acrylate-based compound or an ethylenically unsaturated monomer containing one or more ethylenically unsaturated groups in one molecule, such as a monofunctional monomer, a bifunctional monomer, a trifunctional or higher monomer, can be used. Among these, it is preferable to use the urethane (meth) acrylate compound (b1) and the ethylenically unsaturated monomer (b2) from the viewpoint of excellent curing speed and ultimate physical properties.
In addition, the unsaturated group-containing compound (B) may be a compound containing an oxyalkylene structure, a hydroxyl group, or an acid-base ion pair and / or a structural portion exhibiting hydrophilicity such as a betaine structure. From the viewpoint of

  The urethane (meth) acrylate compound (b1) is a (meth) acrylate compound having a urethane bond in the molecule, and can be produced by reacting a (meth) acrylic compound containing a hydroxyl group with a polyvalent isocyanate compound. .

  The (meth) acrylic compound containing the hydroxyl group is not particularly limited, and examples thereof include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4- Hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 2- (meth) acryloyloxyethyl-2-hydroxypropyl phthalate, 2-hydroxy-3- (meth) acryloyloxypropyl (meth) acrylate, Caprolactone-modified 2-hydroxyethyl (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, caprolactone-modified dipentaerythritol penta (meth) acrylate, capro Examples include kuton-modified pentaerythritol tri (meth) acrylate, ethylene oxide-modified dipentaerythritol penta (meth) acrylate, and ethylene oxide-modified pentaerythritol tri (meth) acrylate. Among them, hydroxyl group-containing (meta) having three or more acryloyl groups ) Acrylic compounds are preferably used. Moreover, these can be used 1 type or in combination of 2 or more types.

  The polyvalent isocyanate compound is not particularly limited, and examples thereof include aromatic, aliphatic, and alicyclic polyisocyanates. Among them, tolylene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, Polyphenylmethane polyisocyanate, modified diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, tetramethylxylylene diisocyanate, isophorone diisocyanate, norbornene diisocyanate, 1,3-bis (isocyanato) Methyl) cyclohexane, phenylene diisocyanate, lysine diisocyanate, lysine triisocyanate And polyisocyanates such as naphthalene diisocyanate, trimer compounds or multimeric compounds of these polyisocyanates, burette-type polyisocyanates, water-dispersed polyisocyanates (for example, “Aquanate 100”, “Aqua Nate 110 ”,“ Aquanate 200 ”,“ Aquanate 210 ”, etc.), or the reaction products of these polyisocyanates and polyols. Among these, isophorone diisocyanate, tolylene diisocyanate, hexamethylene diisocyanate, and their trimer compounds or multimeric compounds are preferably used.

  Examples of the polyol include, but are not limited to, alkylene glycols such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butylene glycol, and polybutylene glycol. Compounds, 1,6-hexanediol, neopentyl glycol, cyclohexanedimethanol, hydrogenated bisphenol A, polycaprolactone, trimethylolethane, trimethylolpropane, polytrimethylolpropane, pentaerythritol, polypentaerythritol, sorbitol, mannitol, Multivalent alcohols such as glycerin, polyglycerin, polytetramethylene glycol A polyether polyol having at least one structure of polyethylene oxide, polypropylene oxide, ethylene oxide / propylene oxide block or random copolymerization; the polyhydric alcohol or polyether polyol and maleic anhydride, maleic acid, fumaric acid, anhydrous Polyester polyols that are condensates with polybasic acids such as itaconic acid, itaconic acid, adipic acid, and isophthalic acid; caprolactone-modified polyols such as caprolactone-modified polytetramethylene polyol; polyolefin-based polyols; polybutadiene-based polyols such as hydrogenated polybutadiene polyols Etc. Among these, polyethylene glycol derivatives are preferably used, and polyethylene glycol and polyethylene glycol monomethyl ether are particularly preferably used.

  Furthermore, as the polyol, for example, 2,2-bis (hydroxymethyl) butyric acid, tartaric acid, 2,4-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, 2,2-bis (hydroxymethyl) propionic acid, 2,2-bis (hydroxyethyl) propionic acid, 2,2-bis (hydroxypropyl) propionic acid, dihydroxymethylacetic acid, bis (4-hydroxyphenyl) acetic acid, 4,4-bis (4-hydroxyphenyl) pentanoic acid Also included are carboxyl group-containing polyols such as homogentisic acid, sulfonic acid group or sulfonate group-containing polyols such as sodium 1,4-butanediolsulfonate.

  When using the reaction product of polyisocyanate and polyol, for example, it may be used as a terminal isocyanate group-containing polyisocyanate obtained by reacting the polyol with the polyisocyanate. In the reaction between the polyisocyanate and the polyol, a metal catalyst such as dibutyltin dilaurate or an amine catalyst such as 1,8-diazabicyclo [5.4.0] undecene-7 is used for the purpose of promoting the reaction. Is also preferable.

  In addition, it is also preferable to use an oxyalkylene structure-containing urethane (meth) acrylate compound as the urethane (meth) acrylate compound (b1) in view of excellent antistatic performance.

  The oxyalkylene structure-containing urethane (meth) acrylate compound is obtained by using an alkylene glycol compound among the polyols, and the structure of the oxyalkylene structure-containing urethane (meth) acrylate compound is as follows. One of the hydroxyl groups at both ends of the alkylene glycol compound reacts with an isocyanate group, and the other is a urethane (meth) acrylate having an oxyalkylene structure remaining as a hydroxyl group, which is cured by irradiation with active energy rays. Even after this, the degree of freedom of the oxyalkylene structure is large, and ions are easily transported, which is preferable in terms of exhibiting excellent antistatic performance.

  The oxyalkylene structure-containing urethane (meth) acrylate compound is obtained by using an alkylene glycol compound having only one hydroxyl group instead of the polyol alkylene glycol compound having a plurality of hydroxyl groups. It may be a thing. Examples of the alkylene glycol compounds having only one hydroxyl group include polyethylene glycol monomethyl ether, polyethylene glycol monoallyl ether, polyethylene glycol lauryl ether, polyethylene glycol cetyl ether, polyethylene glycol stearyl ether, polyethylene glycol nonyl phenyl ether, polyethylene glycol Examples include alkyl group-containing polyalkylene glycol derivatives such as polyethylene glycol derivatives such as tridecyl ether, polyethylene glycol oleyl ether, polyethylene glycol octyl phenyl ether, polyoxyethylene oleyl cetyl ether, and polypropylene glycol derivatives such as polypropylene glycol monomethyl ether.

  The method for producing the urethane (meth) acrylate compound is not particularly limited. For example, a method of mixing a hydroxyl group-containing (meth) acrylic compound and a polyvalent isocyanate compound and reacting at 30 to 80 ° C. for 2 to 10 hours. Can be given. In this reaction, it is preferable to use a urethanization catalyst such as tin octenoate, di-n-butyltin dilaurate, lead octylate, potassium octylate, potassium acetate, stannous octoate, or triethylenediamine.

  The weight average molecular weight of the urethane (meth) acrylate compound is preferably 300 to 4000, more preferably 400 to 3000, and particularly preferably 500 to 2000. That is, if the weight average molecular weight is too small, the cohesive force tends to be insufficient after curing, and if it is too large, the viscosity becomes too high and production tends to be difficult.

  As the urethane (meth) acrylate compound in the present invention, it is also preferable to use a urethane (meth) acrylate compound having a quaternary ammonium salt structure or an imidazolium salt in the molecule. In addition, it is preferable that the urethane (meth) acrylate compound has a structure in which an isocyanate group is intentionally left, from the viewpoint of improving the durability by making the network of the unsaturated group-containing compound and the acrylic resin dense.

  As the ethylenically unsaturated monomer (b2) used in the present invention, a monofunctional monomer, a bifunctional monomer, a trifunctional or higher monomer, and the like can be used.

  As said monofunctional monomer, what is necessary is just a monomer containing one ethylenically unsaturated group, for example, styrene, vinyl toluene, chlorostyrene, (alpha) -methylstyrene, methyl (meth) acrylate, ethyl (meth) acrylate, Acrylonitrile, vinyl acetate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, phenoxyethyl (meth) acrylate, 2-phenoxy-2-hydroxypropyl (meth) Acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 3-chloro-2-hydroxypropyl (meth) acrylate, glycerin mono (meth) acrylate, glycidyl (meth) acrylate, lauryl (meth) acrylate Lilate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, tricyclodecanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, n-butyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate , Octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, dodecyl (meth) acrylate, n-stearyl (meth) acrylate, benzyl (meth) acrylate, phenol ethylene oxide modified ( Of phthalic acid derivatives such as (meth) acrylate, nonylphenol propylene oxide modified (meth) acrylate, 2- (meth) acryloyloxy-2-hydroxypropyl phthalate Half ester (meth) acrylate, furfuryl (meth) acrylate, carbitol (meth) acrylate, benzyl (meth) acrylate, butoxyethyl (meth) acrylate, allyl (meth) acrylate, acryloylmorpholine, 2-hydroxyethylacrylamide, N -Methylol (meth) acrylamide, N-vinylpyrrolidone, 2-vinylpyridine, 2- (meth) acryloyloxyethyl acid phosphate monoester and the like.

  Examples of the monofunctional monomer include, in addition to the above, a Michael adduct of acrylic acid or 2-acryloyloxyethyl dicarboxylic acid monoester. Examples of the Michael adduct of acrylic acid include acrylic acid dimer, methacrylic acid dimer, and acrylic acid. Trimers, methacrylic acid trimers, acrylic acid tetramers, methacrylic acid tetramers, and the like. Examples of the 2-acryloyloxyethyl dicarboxylic acid monoester that is a carboxylic acid having a specific substituent include 2-acryloyloxyethyl succinic acid monoester, 2-methacryloyloxyethyl succinic acid monoester, and 2-acryloyloxy. Examples thereof include ethylphthalic acid monoester, 2-methacryloyloxyethylphthalic acid monoester, 2-acryloyloxyethyl hexahydrophthalic acid monoester, and 2-methacryloyloxyethyl hexahydrophthalic acid monoester. Furthermore, oligoester acrylate is also mentioned.

  The bifunctional monomer may be any monomer containing two ethylenically unsaturated groups. For example, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene Glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, ethylene Oxide modified bisphenol A type di (meth) acrylate, propylene oxide modified bisphenol A type di (meth) acrylate, 1,6-hexanediol di (meth) acrylate 1,6-hexanediol ethylene oxide modified di (meth) acrylate, glycerin di (meth) acrylate, pentaerythritol di (meth) acrylate, ethylene glycol diglycidyl ether di (meth) acrylate, diethylene glycol diglycidyl ether di ( (Meth) acrylate, diglycidyl phthalate di (meth) acrylate, hydroxypivalic acid-modified neopentyl glycol di (meth) acrylate, isocyanuric acid ethylene oxide-modified diacrylate, 2- (meth) acryloyloxyethyl acid phosphate diester It is done.

  The tri- or higher functional monomer may be any monomer containing three or more ethylenically unsaturated groups. For example, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) ) Acrylate, dipentaerythritol tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tri (meth) acryloyloxyethoxytrimethylolpropane, Glycerin polyglycidyl ether poly (meth) acrylate, isocyanuric acid ethylene oxide modified tri (meth) acrylate, ethylene oxide modified dipentaerythritol (Meth) acrylate, ethylene oxide modified dipentaerythritol hexa (meth) acrylate, ethylene oxide modified pentaerythritol tri (meth) acrylate, ethylene oxide modified pentaerythritol tetra (meth) acrylate, succinic acid modified pentaerythritol tri (meth) acrylate Etc.

  Among the ethylenically unsaturated monomers (b2), a compound containing an oxyalkylene structure is preferably used, and the oxyalkylene structure-containing ethylenically unsaturated monomer is not particularly limited. And monofunctional ethylenically unsaturated monomers, bifunctional ethylenically unsaturated monomers, trifunctional or higher functional ethylenically unsaturated monomers, which contain an oxyalkylene structure as described below.

  Examples of the monofunctional ethylenically unsaturated monomer containing the oxyalkylene structure include a monofunctional ethylenically unsaturated monomer containing an oxyalkylene structure represented by the following general formula (2).

(In the formula, X is an alkylene group, n is an integer of 1 or more, A is a (meth) acryloyl group or alkenyl group, and B is a hydrogen atom, an alkyl group, a phenyl group, or an acyl group.)

  X in the general formula (2) is an alkylene group, among which an alkylene group having 1 to 10 carbon atoms is preferable, and in particular, an alkylene group having 1 to 4 carbon atoms such as an ethylene group, a propylene group, or a tetramethylene group. Is preferred. In the case where n is a polyoxyalkylene structure moiety having 2 or more, a homopolymer having the same oxyalkylene structure may be used, or different oxyalkylene structures may be copolymerized randomly or in a block form.

  A in the general formula (2) is a (meth) acryloyl group or an alkenyl group. As the alkenyl group, those having 2 to 6 carbon atoms, for example, a vinyl group or an allyl group are usually used. Among these, a methacryloyl group, an acryloyl group, and an allyl group are preferable, and a methacryloyl group and an acryloyl group are particularly preferable.

  B in the said General formula (2) is a hydrogen atom, an alkyl group, a phenyl group, or an acyl group, As a alkyl group, C1-C20 normally, Preferably the thing of 1-10 is used. Among these, a hydrogen atom, a methyl group, and an ethyl group are preferable.

  N in the general formula (2) is an integer of 1 or more, preferably 1 to 500, particularly preferably 2 to 100, and further preferably 3 to 50. If the value of n is too large, the durability tends to be insufficient.

  Specific examples of the monofunctional monomer containing the oxyalkylene structure include the following.

[A: In the case of (meth) acryloyl group]
For example, polyethylene glycol derivatives such as polyethylene glycol mono (meth) acrylate, polypropylene glycol derivatives such as polypropylene glycol mono (meth) acrylate, polyethylene glycol-polypropylene glycol-mono (meth) acrylate, poly (ethylene glycol-tetramethylene glycol) mono (Meth) acrylate, poly (propylene glycol-tetramethylene glycol) mono (meth) acrylate, alkoxy polyethylene glycol (meth) acrylate and the like.

[A: In the case of an alkenyl group]
Examples thereof include polyethylene glycol derivatives such as polyethylene glycol monoallyl ether, polypropylene glycol derivatives such as polypropylene glycol monoallyl ether, and polyethylene glycol-polypropylene glycol-monoallyl ether.

  Among them, polyethylene glycol derivatives are preferable, and n (ethylene oxide addition mole number) in the general formula (2) is 5 to 500, particularly 5 to 100, more preferably 6 to 30, and antistatic ability and durability. It is preferable in terms of balance. If the ethylene oxide addition mole number n is too small, the antistatic ability tends to be inferior, and if it is too large, the durability tends to deteriorate. Furthermore, A is preferably a (meth) acryloyl group from the viewpoint of influence on curability.

  Moreover, as a weight average molecular weight of the monofunctional ethylenically unsaturated monomer containing the oxyalkylene structure shown by the said General formula (2), 100-20000 are preferable normally, Especially 200-10000, Furthermore, 300-1000. Is preferred. If the weight average molecular weight is too small, the antistatic ability tends to be inferior, and if it is too large, the heat-and-moisture resistance tends to decrease.

  Examples of the bifunctional ethylenically unsaturated monomer containing the oxyalkylene structure include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, and polyethylene glycol di (meth). ) Acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, ethylene oxide modified bisphenol A Type di (meth) acrylate, propylene oxide modified bisphenol A type di (meth) acrylate, 1,6-hexanediol ethylene oxide modified Di (meth) acrylate, glycerin di (meth) acrylate, pentaerythritol di (meth) acrylate, ethylene glycol diglycidyl ether di (meth) acrylate, diethylene glycol diglycidyl ether di (meth) acrylate, diglycidyl phthalate di (meta) ) Acrylate, hydroxypivalic acid-modified neopentyl glycol di (meth) acrylate, isocyanuric acid ethylene oxide-modified diacrylate, and the like.

  Examples of the trifunctional or higher functional ethylenically unsaturated monomer containing the oxyalkylene structure include, for example, isocyanuric acid ethylene oxide-modified triacrylate, ethylene oxide-modified dipentaerythritol penta (meth) acrylate, ethylene oxide-modified dipentaerythritol hexa ( And (meth) acrylate, ethylene oxide-modified pentaerythritol tri (meth) acrylate, ethylene oxide-modified pentaerythritol tetra (meth) acrylate, and the like.

  Among the unsaturated group-containing compounds (B), a urethane (meth) acrylate compound (b1) or an ethylenically unsaturated monomer (b2) containing an oxyalkylene structure is used in that it exhibits excellent antistatic performance. Is also preferable. In particular, an unsaturated group-containing compound containing an oxyalkylene structure or containing three or more unsaturated groups is preferred.

  In addition, it is also preferable to use a (meth) acrylate compound containing an acid-base ion pair and / or a betaine structure in the molecule as the unsaturated group-containing compound (B) from the viewpoint of further improving the antistatic ability. .

  As a method for producing a (meth) acrylate compound containing an acid-base ion pair and / or a betaine structure in the molecule, for example, potassium hydroxide is added to a polyfunctional (meth) acrylate monomer containing a carboxyl group. Although the method of making it react is mention | raise | lifted, it is not limited to this. Specifically, a neutralized product of (meth) acrylic acid such as potassium (meth) acrylate, a neutralized potassium hydroxide of M-510 manufactured by Toagosei Co., Ltd., and the like are preferably used.

Moreover, an ionic compound containing a polymerizable unsaturated group can also be used as the unsaturated group-containing compound (B), for example, 1- (2- (meth) acryloyloxyethyl) -3-octylimidazolium. Halogen salts of (meth) acryloyloxyalkyl-3-alkylimidazoliums such as bromide and 1- (2- (meth) acryloyloxyethyl) -3-octylimidazolium chloride, 1- (2- (meth) acrylic (Meth) acryloyloxyethyl-3-alkyl such as leuoxyethyl) -3-octylimidazolium trifluoromethanesulfonimide and 1- (2- (meth) acryloyloxyethyl) -3-octylimidazolium tetrafluoroborate (Meth) acrylic imidazolium cation compounds such as fluorine-containing salts of imidazolium, Of cyano group-containing anions such as 1- (2- (meth) acryloyloxyethyl) -3-alkylimidazolium dicyanamide and 1- (2- (meth) acryloyloxyethyl) -3-alkylimidazolium thiocyanate Vinyl imidazolium cation systems such as (meth) acrylic imidazolium cation compounds, 1-butyl-3-vinylimidazolium tetrafluoroborate (1B3VIBF4), 1-butyl-3-vinylimidazolium trifluoromethanesulfonimide (1B3VITFSI) Examples thereof include an ionic liquid containing a compound and a halogen ion as an anionic component and a cyano group-containing anion.
In addition, the ionic liquid in this invention represents the ionic substance containing the cation component and anion component which hold | maintain a liquid at the fixed temperature of the range of 0-100 degreeC.

  These unsaturated group containing compounds (B) may be used independently and may use 2 or more types together.

  The content of the unsaturated group-containing compound (B) is usually preferably less than that of the acrylic resin (A), and specifically, 5 to 99 weights with respect to 100 parts by weight of the acrylic resin (A). Parts, more preferably 5 to 50 parts by weight, still more preferably 8 to 30 parts by weight. If the content of the unsaturated group-containing compound (B) is too large, the compatibility with the resin is deteriorated and the coating tends to be whitened. If the content is too small, the crosslinking density of the pressure-sensitive adhesive is insufficient. Leakage prevention and durability tend to decrease.

The pressure-sensitive adhesive for optical members of the present invention is obtained by crosslinking the pressure-sensitive adhesive composition [I] containing the acrylic resin (A) and the unsaturated group-containing compound (B) with active energy rays and / or heat. Is. In this crosslinking, a polymerization initiator and a crosslinking agent are not necessarily required, but it is preferable that a polymerization initiator (C) and / or a crosslinking agent (D) be present as necessary.
In the present invention, the pressure-sensitive adhesive composition [I] preferably contains the acrylic resin (A) as a main component. Here, the “main component” means that the acrylic resin ( It means that A) is usually contained in an amount of 50% by weight or more, preferably 60% by weight or more, more preferably 70% by weight or more based on the total amount of the pressure-sensitive adhesive composition [I].

  In the case of crosslinking by the active energy ray and / or heat (irradiation with active energy ray and / or heating), the above-mentioned acrylic resin (A), unsaturated group-containing compound (B) is used as the pressure-sensitive adhesive composition [I]. In addition, it is preferable to further contain a polymerization initiator (C) in that the reaction at the time of irradiation with active energy rays can be stabilized.

  As the polymerization initiator (C), for example, various polymerization initiators such as a photopolymerization initiator (c1) and a thermal polymerization initiator (c2) can be used. Use of c1) is preferable in that it can be crosslinked (cured) by irradiation with active energy rays such as ultraviolet rays for a very short time.

  Moreover, when using the said photoinitiator (c1), adhesive composition [I] is bridge | crosslinked by active energy ray irradiation, and when using a thermal polymerization initiator (c2), adhesive composition [ I] is cross-linked, but it is also preferable to use both together if necessary.

  The photopolymerization initiator (c1) is not particularly limited, and examples thereof include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethyl ketal, 4- (2 -Hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexylphenylketone, 2-methyl-2-morpholino (4-thiomethylphenyl) propan-1-one, 2-benzyl-2- Acetophenones such as dimethylamino-1- (4-morpholinophenyl) butanone and 2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propanone oligomer; benzoin, benzoin methyl ether, benzoin ethyl Ether, benzoin isopropyl ether, benzoy Benzoins such as isobutyl ether; benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide, 3,3 ', 4,4'-tetra (t-butylperoxy Carbonyl) benzophenone, 2,4,6-trimethylbenzophenone, 4-benzoyl-N, N-dimethyl-N- [2- (1-oxo-2-propenyloxy) ethyl] benzenemethananium bromide, (4-benzoyl) Benzophenones such as (benzyl) trimethylammonium chloride; 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 1-chloro-4-propoxythioxanthone, 2- (3-dimethyl Thioxanthones such as mino-2-hydroxy) -3,4-dimethyl-9H-thioxanthone-9-one mesochloride; 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis (2,6-dimethoxybenzoyl) Acylphosphones such as -2,4,4-trimethyl-pentylphosphine oxide and bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide; In addition, as for these photoinitiators (c1), only 1 type may be used independently and 2 or more types may be used together.

  These auxiliary agents include triethanolamine, triisopropanolamine, 4,4′-dimethylaminobenzophenone (Michler ketone), 4,4′-diethylaminobenzophenone, 2-dimethylaminoethylbenzoic acid, 4-dimethylaminobenzoic acid. Ethyl, 4-dimethylaminobenzoic acid (n-butoxy) ethyl, isoamyl 4-dimethylaminobenzoate, 2-ethylhexyl 4-dimethylaminobenzoate, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone Etc. can be used in combination.

  Among these, benzyldimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, benzoin isopropyl ether, 4- (2-hydroxyethoxy) -phenyl (2-hydroxy-2-propyl) ketone, 2-hydroxy-2-methyl-1- It is preferable to use phenylpropan-1-one.

  Examples of the thermal polymerization initiator (c2) include methyl ethyl ketone peroxide, cyclohexanone peroxide, methyl cyclohexanone peroxide, methyl acetoacetate peroxide, acetyl acetate peroxide, 1,1-bis (t-hexyl peroxide). ) -3,3,5-trimethylcyclohexane, 1,1-bis (t-hexylperoxy) -cyclohexane, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, 1, 1-bis (t-butylperoxy) -2-methylcyclohexane, 1,1-bis (t-butylperoxy) -cyclohexane, 1,1-bis (t-butylperoxy) cyclododecane, 1,1- Bis (t-butylperoxy) butane, 2,2-bis (4 -Di-t-butylperoxycyclohexyl) propane, p-menthane hydroperoxide, diisopropylbenzene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, t-hexyl hydroper Oxide, t-butyl hydroperoxide, α, α′-bis (t-butylperoxy) diisopropylbenzene, dicumyl peroxide, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane, t-Butyl cumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexyne-3, isobutyryl peroxide, 3,5,5-trimethylhexa Noyl peroxide, octanoyl per Oxide, lauroyl peroxide, stearoyl peroxide, succinic acid peroxide, m-toluoyl benzoyl peroxide, benzoyl peroxide, di-n-propyl peroxydicarbonate, diisopropyl peroxydicarbonate, bis (4-t-butyl) (Cyclohexyl) peroxydicarbonate, di-2-ethoxyethyl peroxydicarbonate, di-2-ethoxyhexyl peroxydicarbonate, di-3-methoxybutyl peroxydicarbonate, di-s-butyl peroxydicarbonate, Di (3-methyl-3-methoxybutyl) peroxydicarbonate, α, α'-bis (neodecanoylperoxy) diisopropylbenzene, cumylperoxyneodecanoate, 1,1,3,3-te Lamethylbutyl peroxyneodecanoate, 1-cyclohexyl-1-methylethylperoxyneodecanoate, t-hexylperoxyneodecanoate, t-butylperoxyneodecanoate, t-hexylperoxy Pivalate, t-butylperoxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 2,5-dimethyl-2,5-bis (2-ethylhexanoylper) Oxy) hexanoate, 1-cyclohexyl-1-methylethylperoxy-2-ethylhexanoate, t-hexylperoxy-2-ethylhexanoate, t-butylperoxy-2-ethylhexanoate, t- Hexyl peroxyisopropyl monocarbonate, t-butyl peroxyisobutyrate t-butyl peroxymalate, t-butyl peroxy-3,5,5-trimethylhexanoate, t-butyl peroxylaurate, t-butyl peroxyisopropyl monocarbonate, t-butyl peroxy-2 -Ethylhexyl monocarbonate, t-butyl peroxyacetate, t-butyl peroxy-m-toluylbenzoate, t-butyl peroxybenzoate, bis (t-butylperoxy) isophthalate, 2,5-dimethyl-2,5 -Bis (m-toluylperoxy) hexane, t-hexylperoxybenzoate, 2,5-dimethyl-2,5-bis (benzoylperoxy) hexane, t-butylperoxyallyl monocarbonate, t-butyltrimethylsilylper Oxide, 3,3 ', 4,4'-tetra Organic peroxide initiators such as (t-butylperoxycarbonyl) benzophenone and 2,3-dimethyl-2,3-diphenylbutane; 2-phenylazo-4-methoxy-2,4-dimethylvaleronitrile, 1- [(1-cyano-1-methylethyl) azo] formamide, 1,1′-azobis (cyclohexane-1-carbonitrile), 2,2′-azobis (2-methylbutyronitrile), 2,2′- Azobisisobutyronitrile, 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (2-methylpropionamidine) dihydrochloride, 2,2'-azobis (2-methyl- N-phenylpropionamidine) dihydrochloride, 2,2'-azobis [N- (4-chlorophenyl) -2-methylpropionamidine] Hydride chloride, 2,2'-azobis [N- (4-hydrophenyl) -2-methylpropionamidine] dihydrochloride, 2,2'-azobis [2-methyl-N- (phenylmethyl) propionamidine] dihydrochloride 2,2'-azobis [2-methyl-N- (2-propenyl) propionamidine] dihydrochloride, 2,2'-azobis [N- (2-hydroxyethyl) -2-methylpropionamidine] dihydrochloride, 2,2'-azobis [2- (5-methyl-2-imidazolin-2-yl) propane] dihydrochloride, 2,2'-azobis [2- (2-imidazolin-2-yl) propane] dihydrochloride, 2,2'-azobis [2- (4,5,6,7-tetrahydro-1H-1,3-diazepin-2-yl) Lopan] dihydrochloride, 2,2'-azobis [2- (3,4,5,6-tetrahydropyrimidin-2-yl) propane] dihydrochloride, 2,2'-azobis [2- (5-hydroxy-3 , 4,5,6-tetrahydropyrimidin-2-yl) propane] dihydrochloride, 2,2'-azobis [2- [1- (2-hydroxyethyl) -2-imidazolin-2-yl] propane] dihydrochloride 2,2'-azobis [2- (2-imidazolin-2-yl) propane], 2,2'-azobis [2-methyl-N- [1,1-bis (hydroxymethyl) -2-hydroxyethyl] ] Propionamide], 2,2'-azobis [2-methyl-N- [1,1-bis (hydroxymethyl) ethyl] propionamide], 2,2'-azobis [2-me Til-N- (2-hydroxyethyl) propionamide], 2,2'-azobis (2-methylpropionamide), 2,2'-azobis (2,4,4-trimethylpentane), 2,2'- Azobis (2-methylpropane), dimethyl-2,2-azobis (2-methylpropionate), 4,4'-azobis (4-cyanopentanoic acid), 2,2'-azobis [2- (hydroxymethyl ) Propionitrile] and the like; and the like. In addition, only 1 type may be used independently for these thermal polymerization initiators, and 2 or more types may be used together.

  The content of the polymerization initiator (C) is preferably 0.01 to 10 parts by weight, more preferably 0.1 to 7 parts by weight, particularly preferably 100 parts by weight of the acrylic resin (A). Is 0.3 to 3 parts by weight. If the content of the polymerization initiator (C) is too small, the curability tends to be poor and the physical properties tend not to be stable, and if it is too much, no further effect can be obtained.

  In the active energy ray irradiation, far ultraviolet rays, ultraviolet rays, near ultraviolet rays, infrared rays and other electromagnetic waves, X rays, γ rays and other electromagnetic waves, as well as electron beams, proton rays, neutron rays, etc. can be used. Curing by ultraviolet irradiation is advantageous from the standpoint of availability of the device and price. In addition, when performing electron beam irradiation, it can harden | cure without using the said photoinitiator (c1).

As the light source for the ultraviolet irradiation, a high pressure mercury lamp, an electrodeless lamp, an ultrahigh pressure mercury lamp, a carbon arc lamp, a xenon lamp, a metal halide lamp, a chemical lamp, a black light, or the like is used. In the case of the high-pressure mercury lamp, for example, it is performed under conditions of 5 to 3000 mJ / cm ² , preferably 10 to 1000 mJ / cm ² . Moreover, in the case of the said electrodeless lamp, it is performed on the conditions of 2-1500 mJ / cm < ² >, for example, Preferably 5-500 mJ / cm < ² >. The irradiation time varies depending on the type of the light source, the distance between the light source and the coating surface, the coating thickness, and other conditions, but it may usually be several seconds to several tens of seconds, and in some cases, may be a fraction of a second.
On the other hand, in the case of the electron beam irradiation, for example, an electron beam having an energy in the range of 50 to 1000 Kev is used, the irradiation amount is 2 to 50 Mrad, and the irradiation time is the type of the light source and the distance between the light source and the coating surface. Depending on the coating thickness and other conditions, it is usually several seconds to several tens of seconds, and in some cases, a fraction of a second is preferred.

  Moreover, when using a thermal-polymerization initiator (c2) as said polymerization initiator (C), a polymerization reaction is started and advanced by heating. The treatment temperature and treatment time during crosslinking by heating vary depending on the type of thermal polymerization initiator (c2) used, and are usually calculated from the half-life of the initiator, but the treatment temperature is usually The temperature is preferably 70 ° C to 170 ° C, and the treatment time is usually preferably 0.2 to 20 minutes, and particularly preferably 0.5 to 10 minutes.

  Here, the adhesive composition [I] containing the acrylic resin (A), the unsaturated group-containing compound (B), and the polymerization initiator (C) is irradiated with active energy rays and / or heated. Then, the unsaturated group-containing compound (B) is polymerized (polymerized), and crosslinking (physical crosslinking) with the acrylic resin (A) is performed. When the acrylic resin (A) contains an unsaturated group in the side chain, the unsaturated group-containing acrylic is not limited to polymerization of the unsaturated group-containing compound (B) by active energy rays and / or heat. Polymerization of the resin (A) and the unsaturated group-containing compound (B) is also formed.

  In the present invention, it is preferable that the pressure-sensitive adhesive composition [I] further contains a cross-linking agent (D) and is cross-linked by the cross-linking agent in terms of increasing cohesive force and improving durability.

  When the crosslinking agent (D) is used, the acrylic resin (A) preferably has a functional group, and crosslinking (chemical crosslinking) is performed by reacting the functional group with the crosslinking agent.

  As said crosslinking agent (D), what is necessary is just a compound which has a functional group which reacts with the functional group contained in the said acrylic resin (A), for example, an isocyanate type compound, an epoxy-type compound, an aziridine type compound, a melamine type Examples include compounds, aldehyde compounds, amine compounds, and metal chelate compounds. Among these, an isocyanate compound is preferably used from the viewpoint of improving the adhesion with the base material and the reactivity with the base polymer.

  Examples of the isocyanate compound include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, hydrogenated tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, and hexamethylene diisocyanate. , Diphenylmethane-4,4-diisocyanate, isophorone diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, tetramethylxylylene diisocyanate, 1,5-naphthalene diisocyanate, triphenylmethane triisocyanate, and polyisocyanate compounds thereof Examples include adducts with polyol compounds such as trimethylolpropane, burettes and isocyanurates of these polyisocyanate compounds.

  Examples of the epoxy compound include bisphenol A / epichlorohydrin type epoxy resin, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerin diglycidyl ether, glycerin triglycidyl ether, 1,6-hexanediol diglycidyl ether, Examples include trimethylolpropane triglycidyl ether, sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl erythritol, diglycerol polyglycidyl ether, and the like.

  Examples of the aziridine compound include tetramethylolmethane-tri-β-aziridinylpropionate, trimethylolpropane-tri-β-aziridinylpropionate, N, N′-diphenylmethane-4,4 ′. -Bis (1-aziridinecarboxamide), N, N'-hexamethylene-1,6-bis (1-aziridinecarboxyamide) and the like.

  Examples of the melamine compound include hexamethoxymethyl melamine, hexaethoxymethyl melamine, hexapropoxymethyl melamine, hexaptoxymethyl melamine, hexapentyloxymethyl melamine, hexahexyloxymethyl melamine, and melamine resin.

  Examples of the aldehyde compounds include glyoxal, malondialdehyde, succindialdehyde, maleindialdehyde, glutardialdehyde, formaldehyde, acetaldehyde, benzaldehyde and the like.

  Examples of the amine compound include hexamethylenediamine, triethyldiamine, polyethyleneimine, hexamethylenetetraamine, diethylenetriamine, triethyltetraamine, isophoronediamine, amino resin, polyamide, and the like.

  Examples of the metal chelate compounds include multimetallic acetylacetone and acetoacetyl ester coordination compounds such as aluminum, iron, copper, zinc, tin, titanium, nickel, antimony, magnesium, panadium, chromium, and zirconium. .

  Moreover, these crosslinking agents (D) may be used independently and may be used together 2 or more types.

  The content of the crosslinking agent (D) can be appropriately selected depending on the amount of the functional group contained in the acrylic resin (A), the molecular weight of the acrylic resin (A), and the purpose of use. (A) It is preferable that it is 0.1-15 weight part with respect to 100 weight part, Furthermore, it is preferable that it is 0.2-12 weight part, especially 1.5-10 weight part. If the amount of the crosslinking agent (D) is too small, there is a tendency that the cohesive force is insufficient and sufficient durability cannot be obtained. If the amount is too large, the flexibility and adhesive strength are lowered, the durability is deteriorated, and peeling is caused. Therefore, it tends to be difficult to bond the optical member to the optical member.

  In the present invention, in order to further improve the antistatic performance of the pressure-sensitive adhesive obtained by crosslinking the pressure-sensitive adhesive composition [I], a compound having an antistatic performance as a part of the crosslinking agent (D). It is also preferable to use a cross-linking agent into which is introduced.

  As a method for introducing a compound having antistatic performance into such a crosslinking agent, for example, when a polyisocyanate compound is used as the crosslinking agent, a compound having a hydroxyl group in its structure is used as the compound having antistatic performance. The cross-linking agent into which a compound having antistatic performance is partially introduced can be produced by the reaction between the hydroxyl group and the isocyanate group.

  In addition, regarding the introduction of the compound having antistatic performance into the crosslinking agent, a compound having antistatic performance may be introduced into the crosslinking agent in advance and mixed with the acrylic resin (A), or the acrylic resin. (A) At the time of mixing with the crosslinking agent (D), a compound having an antistatic property may be blended at the same time and reacted with the crosslinking agent (D).

  Since the pressure-sensitive adhesive composition [I] of the present invention is used for optical part applications, it is often required to have a high level of antistatic performance. Therefore, it is desirable to further add an antistatic agent (E). . Such an antistatic agent may be a compound having an ionic group, such as an alkali metal salt, alkaline earth metal salt, quaternary ammonium salt, imidazolium salt, aliphatic sulfonate, higher alcohol sulfate ester salt. , Higher alcohol alkylene oxide adduct sulfate ester salt, higher alcohol phosphate ester salt, higher alcohol alcohol alkylene oxide adduct phosphate ester salt, alkylbetaine compound, alkylimidazoline compound, alkylalanine compound, polyvinylbenzyl cationic compound, polyacrylic Examples include acid-type cation compounds. Among these, alkali metal salts, alkaline earth metal salts, quaternary ammonium salts, and imidazolium salts having a cyano group-containing anion are preferably used, and alkali metal salts and imidazolium salts having a cyano group-containing anion are particularly preferably used. Preferably used.

About the said alkali metal salt, it is preferable that it is Li ^<+> , Na ^<+> , K ^{< + >} as a cation part, for example.
Examples of the anion moiety include Cl ⁻ , Br ⁻ , I ⁻ , BF ₄ ⁻ , PF ₆ ⁻ , SCN ⁻ , ClO ₄ ⁻ , CF ₃ COO ⁻ , SbF ₆ ⁻ , NbF ₆ ⁻ , TaF ₆ ⁻ , F (HF) n ⁻ , C ₄ F ₉ SO ₃ ⁻ , C ₃ F ₇ COO ⁻ , CF ₃ SO ₃ ⁻ , (CF ₃ SO ₂ ) ₂ N ⁻ , (CF ₃ SO ₂ ) ₃ C ⁻ , (C ₂ F ₅ SO ₂ ) ₂ N ⁻ , (CF ₃ SO ₂ ) (CF ₃ CO) N ⁻ , AlCl ₄ ⁻ , Al ₂ Cl ₇ ⁻ , ClO ₄ ⁻ , NO ₃ ⁻ , CH ₃ COO ⁻ , CH ₃ SO ₃ ⁻ , AsF ₆ ⁻ , (CN) ₂ N ⁻ , (C ₂ F ₅ SO ₂ ) ₂ N ⁻ , (C ₃ F ₇ SO ₂ ) ₂ N ⁻ , (C ₄ F ₉ SO ₂ ) ₂ N ⁻ , (CF ₃ SO ₂ ) (C ₂ F ₅ SO ₂ ) N ⁻ , (CF ₃ SO ₂ ) (C ₄ F ₉ SO ₂ ) N ⁻ , (C ₂ F ₅ SO ₂ ) (C ₄ FOSO ₂ ) N ^- Although the like can be mentioned. Among _{^{them, BF 4 -, PF 6 -}} , CF 3 COO -, SbF 6 -, NbF 6 -, TaF 6 -, F (HF) n -, C 4 F 9 SO 3 _{^{-, C 3 F 7 COO -}} , CF 3 SO 3 -, (CF 3 SO 2) 2 N -, (CF 3 SO 2) 3 C -, (C 2 F 5 SO 2) 2 N -, (CF 3 Fluorine atom-containing anions such as (SO ₂ ) (CF ₃ CO) N ⁻ are preferred, and (CF ₃ SO ₂ ) ₂ N ⁻ , (CF ₃ SO ₂ ) ₃ C ⁻ , (C ₂ F ₅ ) are particularly preferred. SO ₂ ) ₂ N ⁻ , (CF ₃ SO ₂ ) (CF ₃ CO) N ^{− and} other sulfonyl groups and fluorine atom-containing anions, more preferably (CF ₃ SO ₂ ) ₂ N ⁻ , (C ₂ F _{5 ^{SO 2) 2 N -, (}} CF 3 SO 2) (CF 3 CO) N - sulfonyl group and fluorine atom-containing anionic der having an imide structure such as .
Among these, LiBr, LiI, LiBF ₄ , LiPF ₆ , LiSCN, LiClO ₄ , LiCF ₃ SO ₃ , Li (CF ₃ SO ₂ ) ₂ N, Li (CF ₃ ) are excellent in ion conductivity and excellent in antistatic function. A lithium salt such as SO ₂ ) ₃ C is preferably used.

  Examples of the alkaline earth metal salts include calcium salts, magnesium salts, and halides thereof.

  Examples of the quaternary ammonium salt include quaternary ammonium such as tetraalkyl ammonium sulfonic acid, alkyl trimethyl ammonium salt, dialkyl dimethyl ammonium salt, trialkyl benzyl ammonium salt, alkyl pyridinium salt, and (poly) oxyalkylene trialkyl ammonium salt. A salt is preferably used.

The cyano group-containing anion of imidazolium salts having the cyano group-containing anions, _{^{e.g., S - (CN), N}} - (CN) 2, N - (SO 2 CN) 2, C - (CN) 3, B ^- _{(CN) 4} and the like. among ^{them, S - (CN), N} - (CN) 2 are preferably used.

Specific examples of imidazolium salts having a cyano group-containing anion include, for example, 1,3-dimethylimidazolium dicyanamide, 1-ethyl-3-methylimidazolium dicyanamide, and 1-methyl-3-propylimidazolium dicyanamide. 1-butyl-3-methylimidazolium dicyanamide, 1-methyl-3-pentylimidazolium dicyanamide, 1-hexyl-3-methylimidazolium dicyanamide, 1-heptyl-3-methylimidazolium dicyanamide, 1 -Methyl-3-octylimidazolium dicyanamide, 1-decyl-3-methylimidazolium dicyanamide, 1-dodecyl-3-methylimidazolium dicyanamide, 1-ethyl-3-propylimidazolium dicyanamide, 1-butyl -3-Ethylimidazolium di Dialkylimidazolium dicyanamide such as anamide, 3-ethyl-1,2-dimethyl-imidazolium dicyanamide, 1,2-dimethyl-3-propylimidazolium dicyanamide, 1-butyl-2,3-dimethylimidazolium di Cyanamide, 1,2-dimethyl-3-hexylimidazolium dicyanamide, 1,2-dimethyl-3-octylimidazolium dicyanamide, 1-ethyl-3,4-dimethylimidazolium dicyanamide, 1-isopropyl-2, Trialkylimidazolium dicyanamide such as 3-dimethylimidazolium dicyanamide, 1,3-dimethylimidazolium thiocyanate, 1-ethyl-3-methylimidazolium thiocyanate, 1-methyl-3-propylimidazolium thiocyanate, 1-butyl -3 Methylimidazolium thiocyanate, 1-methyl-3-pentylimidazolium thiocyanate, 1-hexyl-3-methylimidazolium thiocyanate, 1-heptyl-3-methylimidazolium thiocyanate, 1-methyl-3-octylimidazolium thiocyanate, 1 Dialkylimidazolium thiocyanates such as 1-dodecyl-3-methylimidazolium thiocyanate, 1-dodecyl-3-methylimidazolium thiocyanate, 1-ethyl-3-propylimidazolium thiocyanate, 1-butyl-3-ethylimidazolium thiocyanate, 3 -Ethyl-1,2-dimethyl-imidazolium thiocyanate, 1,2-dimethyl-3-propylimidazolium thiocyanate, 1-butyl-2,3-dimethylimidazolium Muthiocyanate, 1,2-dimethyl-3-hexylimidazolium thiocyanate, 1,2-dimethyl-3-octylimidazolium thiocyanate, 1-ethyl-3,4-dimethylimidazolium thiocyanate, 1-isopropyl-2,3- And trialkylimidazolium thiocyanates such as dimethylimidazolium thiocyanate.
Among these, the use of a solid imidazolium salt is preferable because it can be easily recrystallized by purification, and thus it is easy to prepare a high-purity ionic compound, and 1-ethyl-2,3-dimethylimidazolium disulfide is particularly preferable. Cyanamide and 1-ethyl-2,3 dimethylimidazolium thiocyanate are used because they are easy to prepare high-purity ionic compounds.

  Moreover, as an antistatic agent (E), what is called an ionic liquid can also be used among ionic compounds. The ionic liquid in this invention represents the ionic substance containing the cation component and anion component which hold | maintain a liquid at the fixed temperature of the range of 0-100 degreeC.

  The cation component is not particularly limited, and a cation used in a general ionic liquid is used. Examples of such cations include, for example, cations of heterocyclic compounds, particularly cations of 1 to 5 membered heterocyclic compounds containing 1 to 5 heteroatoms, particularly nitrogen atoms as heteroatoms. Examples thereof include cations of 1 to 5 membered heterocyclic compounds containing 1 to 5 heteroatoms, and among them, imidazolium cation, pyrrolidinium cation, piperidinium cation, pyridinium cation and the like are preferable. It is also preferable to use a chain-like quaternary ammonium cation or quaternary phosphonium cation. Among these, imidazolium cation, pyridinium cation, quaternary ammonium cation, and quaternary phosphonium cation are preferable, and imidazolium cation is particularly preferable in terms of low viscosity.

On the other hand, the anion component is not particularly limited. For example, Cl ⁻ , Br ⁻ , AlCl ₄ ⁻ , Al ₂ Cl ₇ ⁻ , BF ₄ ⁻ , PF ₆ ⁻ , ClO ₄ ⁻ , NO ₃ ⁻ , _{^{CH 3 COO -, CF 3 COO}} -, CH 3 SO 3 - CF 3 SO 3 -, (CF 3 SO 2) 2 N -, (CF 3 SO 2) 3 C -, AsF 6 -, SbF 6 -, NbF ₆ ⁻ , TaF ₆ ⁻ , F (HF) n ⁻ , (CN) ₂ N ⁻ , C ₄ F ₉ SO ₃ ⁻ , (C ₂ F ₅ SO ₂ ) ₂ N ⁻ , C ₃ F ₇ COO ⁻ , (CF _{3 SO 2) (CF 3 CO} ) N - it is possible to use an anion commonly used in ionic liquids and the like.

Among the antistatic agents (E), it is particularly preferable that the anion portion is an anion having a sulfonyl group and a fluorine atom-containing imide structure. Specifically, Li (CF ₃ SO ₂ ) ₂ N, Li ( CF ₃ SO ₂ ) ₃ C, 1.2-dimethyl-3-ethyl-imidazolium bis (trifluoromethylsulfonic acid) imide, 1-ethyl-3-methylimidazolium bis (trifluoromethylsulfonic acid) imide, etc. Alkali metal salts and imidazolium salts having an imide structure containing a sulfonyl group and a fluorine atom are particularly preferably used.

  As content of the said antistatic agent (E), it is normally set to 0.001-20 weight part with respect to 100 weight part of acrylic resin (A), More preferably, 0.01-7 weight part, The amount is particularly preferably 0.1 to 5 parts by weight, particularly preferably 0.3 to 3 parts by weight. If the content of the antistatic agent (E) is too small, the effect of addition tends not to be obtained. If the content is too large, the durability may deteriorate or the antistatic agent may bleed out.

  Moreover, in this invention, it is preferable that adhesive composition [I] contains a silane coupling agent (F) further at the point which the adhesiveness with respect to an optical member improves. As content of the said silane coupling agent (F), it is 0.001-10 weight part normally with respect to 100 weight part of acrylic resin (A), More preferably, 0.01-1 weight part, Particularly preferred is 0.03 to 0.8 parts by weight. If the content of the silane coupling agent (F) is too small, there is a tendency that the effect of addition cannot be obtained. If the content is too large, the compatibility with the acrylic resin (A) is poor and adhesive strength and cohesive force cannot be obtained. Tend.

  Examples of the silane coupling agent (F) include epoxy silane coupling agents, acrylic silane coupling agents, mercapto silane coupling agents, hydroxyl group silane coupling agents, carboxyl group silane coupling agents, amino Examples thereof include a base silane coupling agent, an amide group silane coupling agent, and an isocyanate group silane coupling agent. These may be used alone or in combination of two or more. Among these, an epoxy silane coupling agent and a mercapto silane coupling agent are preferably used, and the combined use of an epoxy silane coupling agent and a mercapto silane coupling agent also improves wet heat durability and has adhesive strength. It is preferable in that it does not rise too much.

  Specific examples of the epoxy-based silane coupling agent include, for example, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and γ-glycid. Examples include xylpropylmethyldimethoxysilane, methyltri (glycidyl) silane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, and the like. -Glycidoxypropyltrimethoxysilane, [gamma] -glycidoxypropyltriethoxysilane, [gamma] -glycidoxypropylmethyldiethoxysilane, [beta]-(3,4-epoxycyclohexyl) ethyltrimethoxysilane.

  Specific examples of the mercapto silane coupling agent include γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, and γ-mercaptopropyldimethoxymethylsilane.

  In the present invention, the pressure-sensitive adhesive composition [I], which is a pressure-sensitive adhesive forming material, further includes an oxyalkylene structure-containing compound (G) that does not contain an unsaturated group [hereinafter simply referred to as an oxyalkylene structure-containing compound (G). It may be noted. ] Is preferable in terms of further improving the antistatic performance, improving the compatibility, and lowering the coating film haze.

  The content of the oxyalkylene structure-containing compound (G) is usually set to 1 to 90 parts by weight, preferably 2 to 30 parts by weight, particularly preferably 100 parts by weight of the acrylic resin (A). 3 to 10 parts by weight, particularly preferably 4 to 5 parts by weight. When there is too little content of the said oxyalkylene structure containing compound (G), there exists a tendency for it to be inferior to antistatic ability, and when there is too much, there exists a tendency for adhesive physical property to deteriorate.

  As said oxyalkylene structure containing compound (G), what is necessary is just a compound which has an oxyalkylene structure which does not contain an unsaturated group, and various oxyalkylene structure containing compounds can be used, for example, polyoxyalkylene alkylamine, poly Nonionic such as oxyalkylene diamine, polyoxyalkylene glycol fatty acid ester, polyoxyalkylene sorbitan fatty acid ester, polyoxyalkylene alkyl phenyl ether, polyoxyalkylene alkyl ether, polyoxyalkylene alkyl allyl ether, polyoxyalkylene alkyl phenyl allyl ether Surfactant, polyoxyalkylene alkyl ether sulfate ester salt, polyoxyalkylene alkyl ether phosphate ester salt, polyoxyalkylene Anionic surfactants such as alkyl phenyl ether sulfates and polyoxyalkylene alkyl phenyl ether phosphates, cationic surfactants having an oxyalkylene structure and amphoteric surfactants, polyether esters containing an oxyalkylene structure Etc.

  Among these, oxyethylene group-containing compounds are preferable. Specifically, polyoxyethylene alkylamines, polyoxyethylene diamines, oxyethylene group-containing polyether polymers, oxyethylene group-containing polyether ester amides, oxyethylene group-containing polymers are preferred. Examples include ether amide imide, polyoxyethylene glycol fatty acid ester, polyoxysorbitan acid fatty acid ester, polyoxyethylene alkylphenyl ether, polyoxyethylene alkyl ether, etc., and polyether polymers or acrylic polymers having an oxyethylene group, It is preferably used because it is easy to balance the compatibility with the base polymer.

  Examples of the oxyethylene group-containing polyether polymer include a polypropylene glycol-polyethylene glycol-polypropylene glycol block copolymer, a polypropylene glycol-polyethylene glycol block copolymer, and a polyethylene glycol-polypropylene glycol-polyethylene glycol block copolymer. And random copolymers and block copolymers of polyethylene glycol and polypropylene glycol, such as polypropylene glycol-polyethylene glycol random copolymers. The end of the glycol chain may be a hydroxyl group or may be substituted with an alkyl group, a phenyl group or the like.

  The polyethylene glycol ratio in the random copolymer or block copolymer of polyethylene glycol and polypropylene glycol is preferably 5 to 75% by weight, more preferably 10 to 70% by weight. If the polyethylene glycol ratio is too low, the compatibility with ionic compounds tends to be poor, and sufficient antistatic properties tend to be difficult to obtain. If it is too high, the crystallinity becomes high and the compatibility with acrylic polymers becomes poor. It tends to be difficult to obtain sufficient antistatic properties.

  These compounds may be used alone or in combination of two or more. Among the oxyethylene group-containing compounds, the polyoxyethylene alkyl ether is preferable from the viewpoint of effectively increasing the antistatic ability.

  As the polyoxyethylene alkyl ether, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol diethyl ether and the like having 2 repetitions, triethylene glycol diethyl ether, triethylene glycol ethyl methyl ether, triethylene glycol diethyl ether and the like are repeated. No. 3, triethylene glycol diethyl ether, triethylene glycol ethyl methyl ether, triethylene glycol diethyl ether, higher polyoxyethylene dimethyl ether, and the like. Among these, tetraethylene glycol dimethyl ether is preferably used.

  Moreover, in this invention, it is preferable that the oxyalkylene structure content rate in the said oxyalkylene structure containing compound (G) is 5-85 weight%, It is more preferable that it is 7-80 weight%, 9-75 More preferably, it is% by weight. When the content is too low, the antistatic performance tends to be inferior, and when the content is too high, the composition becomes hydrophilic and tends to be inferior in heat and moisture resistance.

  The molecular weight of the oxyalkylene structure-containing compound (G) is preferably a number average molecular weight of 100 to 10000, particularly preferably 180 to 1000. In addition, the said number average molecular weight is calculated | required by the method similar to the above-mentioned weight average molecular weight.

In the present invention, as the antistatic agent (E), at least one of an alkali metal salt and an alkaline earth metal salt is used by dissolving it in the oxyalkylene structure-containing compound (G) in advance. It is preferable at the point which can melt | dissolve in a system resin (A). If this operation is not performed, the antistatic agent (E) may be difficult to dissolve in the acrylic resin (A).

In the present invention, the pressure-sensitive adhesive composition [I], which is a pressure-sensitive adhesive-forming material, further includes other acrylic pressure-sensitive adhesives, other pressure-sensitive adhesives, urethane resins, rosins, and rosins, as long as the effects of the present invention are not impaired. Esters, hydrogenated rosin esters, phenol resins, aromatic modified terpene resins, aliphatic petroleum resins, alicyclic petroleum resins, styrene resins, xylene resins, tackifiers, colorants, fillers, anti-aging Conventionally known additives such as an agent, an ultraviolet absorber, a functional dye, and the like, and a compound that causes coloration or discoloration upon irradiation with ultraviolet rays or radiation can be blended.
In addition to the above additives, a small amount of impurities contained in the raw materials for producing the constituent components of the pressure-sensitive adhesive composition [I] may be contained.

  Thus, in this invention, the adhesive for optical members obtained by bridge | crosslinking the said adhesive composition [I] is obtained.

  And the optical member with an adhesive layer can be obtained by carrying out lamination formation of the adhesive layer containing the said adhesive on an optical member (optical laminated body).

  It is preferable that the optical member with the pressure-sensitive adhesive layer is further provided with a release sheet on the surface opposite to the optical member surface of the pressure-sensitive adhesive layer.

  Moreover, when using the optical member with an adhesive layer for practical use, the said release sheet is peeled and used. And as said release sheet, it is preferable to use a silicon-type release sheet.

  In the case where the pressure-sensitive adhesive composition [I] is crosslinked by at least one of active energy ray irradiation and heating, [1] after the pressure-sensitive adhesive composition [I] is applied on the optical member and dried, A method of pasting a release sheet and performing treatment with at least one of active energy ray irradiation and heating, [2] After applying the adhesive composition [I] on the release sheet and drying, the optical member Method of pasting and performing treatment by at least one of active energy ray irradiation and heating, [3] Applying and drying adhesive composition [I] on the optical member, and further by at least one of active energy ray irradiation and heating After the treatment, a method of pasting the release sheet, [4] Applying and drying the pressure-sensitive adhesive composition [I] on the release sheet, and further by at least one of active energy ray irradiation and heating After performing the management it can be to produce a method of bonding an optical member, a. Among these, the method [2] and only the active energy ray irradiation are preferable from the viewpoint of not damaging the substrate, workability and stable production.

  In applying the pressure-sensitive adhesive composition [I], it is preferable to dilute the pressure-sensitive adhesive composition [I] in a solvent, and the dilution concentration is preferably 10 to 60% by weight, particularly preferably 11%. ~ 30% by weight. The solvent is not particularly limited as long as it can dissolve the pressure-sensitive adhesive composition [I]. Examples thereof include ester solvents such as methyl acetate, ethyl acetate, methyl acetoacetate, and ethyl acetoacetate, acetone Further, ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone, aromatic solvents such as toluene and xylene, and alcohol solvents such as methanol, ethanol and propyl alcohol can be used. Among these, ethyl acetate, methyl ethyl ketone, and methanol are preferably used from the viewpoints of solubility, drying properties, price, and the like.

  In addition, the application of the pressure-sensitive adhesive composition [I] is performed by a conventional method such as roll coating, die coating, gravure coating, comma coating, or screen printing.

  The gel fraction of the pressure-sensitive adhesive layer produced by the above method is preferably 80% or more, particularly 90% or more from the viewpoint of durability performance and light leakage prevention performance. If the gel fraction is too low, the durability and light leakage phenomenon due to insufficient cohesive force tend to be deteriorated. In general, the upper limit of the gel fraction is 100%.

  In adjusting the gel fraction of the pressure-sensitive adhesive for optical members to the above range, for example, adjusting the irradiation amount and irradiation intensity of the active energy ray, adjusting the type and amount of the unsaturated group-containing compound (B) It is achieved by adjusting the kind of polymerization initiator and its combination ratio, adjusting the blending amount of the polymerization initiator, adjusting the kind and amount of the crosslinking agent, and the like. Moreover, since the gel fraction changes by each interaction, the irradiation amount and irradiation intensity | strength of said active energy ray, the composition ratio of a polymerization initiator, and addition amount need to balance each.

  The gel fraction is a measure of the degree of crosslinking, and is calculated, for example, by the following method. That is, a pressure-sensitive adhesive sheet (not provided with a separator) in which a pressure-sensitive adhesive layer is formed on a polymer sheet (for example, polyethylene terephthalate film or the like) as a base material is wrapped with a 200-mesh SUS wire mesh, and 23 in toluene. The weight percentage of the insoluble pressure-sensitive adhesive component immersed in the wire mesh at 24 ° C. for 24 hours is defined as the gel fraction. However, the weight of the substrate is subtracted.

  Moreover, the thickness of the adhesive layer in the optical member with an adhesive layer obtained is although it does not specifically limit, 10-200 micrometers is preferable and 12-50 micrometers is especially preferable. Furthermore, 13-30 micrometers is preferable. If the thickness of the pressure-sensitive adhesive layer is too thin, the adhesive physical properties tend to be difficult to stabilize, and if it is too thick, the thickness of the entire optical part tends to increase too much.

  The optical member with the pressure-sensitive adhesive layer of the present invention is directly or after having peeled off the release sheet after having a release sheet, the pressure-sensitive adhesive layer surface is bonded to a glass substrate, and used for, for example, a liquid crystal display board.

  The initial adhesive strength of the pressure-sensitive adhesive layer of the present invention is appropriately determined according to the material of the adherend. For example, when sticking on a glass substrate, it preferably has an adhesive strength of 0.2 N / 25 mm to 20 N / 25 mm, more preferably 1 N / 25 mm to 10 N / 25 mm.

  The initial adhesive strength is calculated as follows. About a polarizing plate with an adhesive layer, it cut | judged to width 25mm width, peels a release film, presses the adhesive layer side to a non-alkali glass plate (Corning company make, "Corning 1737"), and a polarizing plate A glass plate is bonded. Then, after performing an autoclave process (50 degreeC, 0.5 MPa, 20 minutes), a 180 degreeC peeling test is done. In addition, in peelability, it is desired that adhesive force is small.

  The optical member in the present invention is not particularly limited, and an optical film suitably used for an image display device such as a liquid crystal display device, an organic EL display device, or a PDP, such as a polarizing plate, a retardation plate, or an elliptical polarizing plate. , Optical compensation films, brightness enhancement films, and those in which these are laminated. Among them, a polarizing plate is particularly effective in the present invention.

  The polarizing plate used in the present invention is usually a laminate of a cellulose triacetate film as a protective film on both sides of a polarizing film. The polarizing film has an average degree of polymerization of 1,500 to 10,000, A uniaxially stretched film dyed with an aqueous solution of iodine-potassium iodide or a dichroic dye using a film made of a polyvinyl alcohol resin having a degree of conversion of 85 to 100 mol% as a raw film (usually 2 to 10 times, preferably Is a stretching ratio of about 3 to 7 times.

  The polyvinyl alcohol resin is usually produced by saponifying polyvinyl acetate obtained by polymerizing vinyl acetate, but a small amount of unsaturated carboxylic acid (including salt, ester, amide, nitrile, etc.), olefins, vinyl ether And a component copolymerizable with vinyl acetate, such as an unsaturated sulfonate. Moreover, what is called polyvinyl acetal resin and polyvinyl alcohol derivatives, such as polybutyral resin and polyvinyl formal resin, which are obtained by reacting polyvinyl alcohol with an aldehyde in the presence of an acid can be mentioned.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist. In the examples, “parts” and “%” mean weight basis unless otherwise specified.

First, various acrylic resins and various unsaturated group-containing compounds were prepared as follows. In addition, regarding the measurement of the weight average molecular weight of acrylic resin, dispersion degree, and glass transition temperature, it measured according to the above-mentioned method.
In addition, regarding the measurement of a viscosity, it measured according to "4.5.3 rotational viscometer method" of JISK5400 (1990).

[Preparation of Acrylic Resin (A)] (See Table 1)

[Acrylic resin (A-1)]
In a 4-neck round bottom flask equipped with a reflux condenser, a stirrer, a nitrogen gas inlet and a thermometer, 30 parts of 2-methoxyethyl acrylate (a1), 67.5 parts of butyl acrylate (a2), 2-hydroxy First, 1.5 parts of ethyl acrylate (a3), 1 part of acrylic acid (a3), 90 parts of ethyl acetate and 45 parts of acetone were charged. After heating and refluxing, 0.03 azobisisobutyronitrile (AIBN) was used as a polymerization initiator. The mixture was reacted at reflux temperature for 3 hours, and diluted with ethyl acetate to obtain an acrylic resin (A-1) solution (weight average molecular weight (Mw) 1530,000, dispersity (Mw / Mn) 3.5, glass A transition temperature of −53 ° C., a solid content of 18%, and a viscosity of 8,000 mPa · s (25 ° C.)) were obtained.

[Acrylic resin (A-2)]
In a 4-neck round bottom flask equipped with a reflux condenser, a stirrer, a nitrogen gas inlet and a thermometer, 40 parts of 2-methoxyethyl acrylate (a1), 57.5 parts of butyl acrylate (a2), 2-hydroxy First, 1.5 parts of ethyl acrylate (a3), 1 part of acrylic acid (a3), 90 parts of ethyl acetate and 45 parts of acetone were charged. After heating and refluxing, 0.03 azobisisobutyronitrile (AIBN) was used as a polymerization initiator. The reaction was carried out at reflux temperature for 3 hours, and then diluted with ethyl acetate to prepare an acrylic resin (A-2) solution (weight average molecular weight (Mw) 151,000, dispersity (Mw / Mn) 3.5, glass A transition temperature of −52 ° C., a solid content of 18%, and a viscosity of 8,000 mPa · s (25 ° C.)) were obtained.

[Acrylic resin (A-3)]
In a 4-neck round bottom flask equipped with a reflux condenser, a stirrer, a nitrogen gas inlet and a thermometer, 60 parts of 2-methoxyethyl acrylate (a1), 37.5 parts of butyl acrylate (a2), 2-hydroxy First, 1.5 parts of ethyl acrylate (a3), 1 part of acrylic acid (a3), 120 parts of ethyl acetate and 45 parts of acetone were charged. After heating and refluxing, 0.03 azobisisobutyronitrile (AIBN) was used as a polymerization initiator. The reaction mixture was reacted at reflux temperature for 3 hours, and then diluted with ethyl acetate to obtain an acrylic resin (A-3) solution (weight average molecular weight (Mw) 1,320,000, dispersity (Mw / Mn) 5.6, glass A transition temperature of −51 ° C., a solid content of 20%, and a viscosity of 5,000 mPa · s (25 ° C.)) were obtained.

[Acrylic resin (A-4)]
In a four-necked round bottom flask equipped with a reflux condenser, a stirrer, a nitrogen gas inlet and a thermometer, 60 parts of 2-methoxyethyl acrylate (a1), 29 parts of butyl acrylate (a2), 2-hydroxyethyl acrylate (A3) 10 parts, acrylic acid (a3) 1 part and ethyl acetate 140 parts, acetone 45 parts were charged. After heating to reflux, azobisisobutyronitrile (AIBN) 0.03 part was added as a polymerization initiator, After reacting at reflux temperature for 3 hours, diluted with ethyl acetate to obtain an acrylic resin (A-4) solution (weight average molecular weight (Mw) 1.32 million, dispersity (Mw / Mn) 4.9, glass transition temperature -48. C, solid content 20%, viscosity 5,000 mPa · s (25 ° C)).

[Acrylic resin (A-5)]
In a 4-neck round bottom flask equipped with a reflux condenser, a stirrer, a nitrogen gas inlet and a thermometer, 20 parts of ethoxydiethylene glycol acrylate (a1), 78 parts of butyl acrylate (a2), 2-hydroxyethyl acrylate (a3 ) 1 part, 1 part of acrylic acid (a3), 140 parts of ethyl acetate and 45 parts of acetone were added. After heating and refluxing, 0.03 part of azobisisobutyronitrile (AIBN) was added as a polymerization initiator, and the reflux temperature was 3 hours after the reaction, and diluted with ethyl acetate to obtain an acrylic resin (A-5) solution (weight average molecular weight (Mw) 1.17 million, dispersity (Mw / Mn) 5.8, glass transition temperature −57 ° C., A solid content of 20% and a viscosity of 6,000 mPa · s (25 ° C.)) were obtained.

[Acrylic resin (A-6)]
In a 4-neck round bottom flask equipped with a reflux condenser, a stirrer, a nitrogen gas inlet and a thermometer, 40 parts of 2-methoxyethyl acrylate (a1), 49 parts of butyl acrylate (a2), 2-hydroxyethyl acrylate (A3) 10 parts, acrylic acid (a3) 1 part and ethyl acetate 140 parts, acetone 45 parts were charged. After heating to reflux, azobisisobutyronitrile (AIBN) 0.03 part was added as a polymerization initiator, After reacting at reflux temperature for 3 hours, diluted with ethyl acetate to obtain an acrylic resin (A-6) solution (weight average molecular weight (Mw) 1.32 million, dispersity (Mw / Mn) 3.5, glass transition temperature -49. C, solid content 20%, viscosity 3,500 mPa · s (25 ° C)).

[Acrylic resin (A′-1)]
In a 4-neck round bottom flask equipped with a reflux condenser, a stirrer, a nitrogen gas inlet and a thermometer, 40 parts of 2-methoxyethyl acrylate (a1), 57.5 parts of butyl acrylate (a2), 2-hydroxy First, 1.5 parts of ethyl acrylate (a3), 1 part of acrylic acid (a3), 90 parts of ethyl acetate and 45 parts of acetone were charged. After heating and refluxing, 0.03 azobisisobutyronitrile (AIBN) was used as a polymerization initiator. After 3 hours of reaction at reflux temperature, polymerization was continued for another 4 hours at reflux temperature while sequentially adding a polymerization initiator solution in which 0.1 part of AIBN was dissolved in 30 parts of toluene during the polymerization, and then ethyl acetate was added. Diluted with an acrylic resin (A′-1) solution (weight average molecular weight (Mw) 1,080,000, dispersity (Mw / Mn) 12.5, glass transition temperature −52 ° C., solid content 20% Viscosity 9,000 mPa · s (25 ° C.)).

[Acrylic resin (A'-2)]
In a 4-neck round bottom flask equipped with a reflux condenser, a stirrer, a nitrogen gas inlet and a thermometer, 20 parts of ethoxydiethylene glycol acrylate (a1), 78 parts of butyl acrylate (a2), 2-hydroxyethyl acrylate (a3 ) 1 part, 1 part of acrylic acid (a3), 140 parts of ethyl acetate and 45 parts of acetone were added. After heating and refluxing, 0.03 part of azobisisobutyronitrile (AIBN) was added as a polymerization initiator, and the reflux temperature was After 3 hours of reaction, the polymerization initiator solution in which 0.1 part of AIBN was dissolved in 30 parts of toluene was added in the middle of the polymerization, followed by further polymerization for 4 hours at the reflux temperature, and then diluted with ethyl acetate to obtain acrylic. Resin (A′-2) solution (weight average molecular weight (Mw) 1,120,000, dispersity (Mw / Mn) 15.2, glass transition temperature −57 ° C., solid content 1 9% and a viscosity of 8,500 mPa · s (25 ° C.)).

[Acrylic resin (A'-3)]
In a 4-neck round bottom flask equipped with a reflux condenser, a stirrer, a nitrogen gas inlet and a thermometer, 98 parts of butyl acrylate (a2), 1.5 parts of 2-hydroxyethyl acrylate (a3), acrylic acid ( a3) 0.5 parts, 75 parts of ethyl acetate and 45 parts of acetone were added, and after heating to reflux, 0.03 part of azobisisobutyronitrile (AIBN) was added as a polymerization initiator, and the mixture was refluxed at ethyl acetate for 3 hours. After the reaction, dilute with ethyl acetate to obtain acrylic resin (A
'-1) Solution (weight average molecular weight (Mw) 2 million, dispersity (Mw / Mn) 3.1, glass transition temperature -54 ° C, solid content 16%, viscosity 8,000 mPa · s (25 ° C)) Obtained.

(Note) BA: Butyl acrylate HEA: 2-Hydroxyethyl acrylate MEA: 2-Methoxyethyl acrylate EDEGA: Ethoxydiethylene glycol acrylate AAc: Acrylic acid * "---" in the table indicates that it was not blended.

[Production of unsaturated group-containing compound (B-1)]
In a 4-neck round bottom flask equipped with a reflux condenser, a stirrer, a nitrogen gas inlet and a thermometer, 19.2 parts of isophorone diisocyanate, 0.05 part of di-t-butylhydroxyphenol, 0.02 of dibutyltin dilaurate The reaction was continued at 70 ° C. at 50 ° C. or less and 80.8 parts of a mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate (Kyoeisha Chemical Co., Ltd., light acrylate PE-3A, hydroxyl value 120 mgKOH / g). Then, an unsaturated group-containing compound (B-1) was obtained.

[Photoinitiator (C)]
The following were prepared as the photopolymerization initiator (C-1).
A mixture of benzophenone and 1-hydroxycyclohexyl phenyl ketone in a mass ratio of 1: 1 (Ciba Specialty Chemicals, “Irgacure 500”)

[Crosslinking agent (D)]
The following were prepared as a crosslinking agent (D-1).
・ 55% ethyl acetate solution of trimethylolpropane tolylene diisocyanate adduct (manufactured by Nippon Polyurethane Co., Ltd., “Coronate L-55E”)

[Antistatic agent (E)]
The following were prepared as the antistatic agent (E).
・ Lithium perchlorate (Nippon Carlid Co., Ltd.) (E-1)
Trifluoromethanesulfonyl lithium (LiCF ₃ SO ₃ ) (Sankonol EAc-30T (E-2) manufactured by Sanko Chemical Co., Ltd.)
Bis (trifluoromethanesulfonyl) imidolithium [Li (CF ₃ SO ₃ ) ₂ N] (Sankonol EAc-20R manufactured by Sanko Chemical) (E-3)
1-ethyl 2,3-dimethylimidazolium dicyanamide (manufactured by Nippon Synthetic Chemical Co., Ltd.) (E-4)
1-ethyl 3-methylimidazolium bis (trifluoromethanesulfonyl) imide (manufactured by Nippon Synthetic Chemical Co., Ltd.) (E-5)

[Silane coupling agent (F)]
The following were prepared as the silane compound (F).
Γ-glycidoxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., “KBM403”) (F-1)
Γ-mercaptopropyltrimethoxysilane (“KBM803” manufactured by Shin-Etsu Chemical Co., Ltd.) (F-2)

[Oxyalkylene structure-containing compound (G)]
The following were prepared as the oxyalkylene structure-containing compound (G).・ Tetraethylene glycol dimethyl ether (Toho Chemical Co., Ltd., “Hisolv MTEM”)

[Examples 1-13, Comparative Examples 1-3]
Prepare the pressure-sensitive adhesive composition to be a pressure-sensitive adhesive forming material for optical members by blending the components prepared and prepared as described above in the proportions shown in Table 2 below, and apply this with methyl ethyl ketone. The pressure-sensitive adhesive composition solution was prepared by diluting to a viscosity of 1000 to 10,000 mPa · s (25 ° C.).

Note) Numerical values in the tables in (A) to (G) are parts by weight.
* “---” in the table indicates that it was not blended.

And after apply | coating the said adhesive composition solution to a polyester-type release sheet so that the thickness after drying may be set to 25 micrometers, and drying for 3 minutes at 90 degreeC, the formed adhesive composition layer is made into a polarizing plate. The film was transferred onto (thickness 190 μm), and irradiated with ultraviolet rays at a peak illuminance of 600 mW / cm ² and an integrated exposure amount of 240 mJ / cm ^{2 using} an electrodeless lamp [H bulb of LH6UV lamp] manufactured by Fusion (120 mJ / cm ² × 2 pass), 23 ° C. × 65% R.D. H. The film was aged for 10 days under the above conditions to obtain a polarizing plate with an adhesive layer. The polarizing plate is laminated with a cellulose triacetate film having a thickness of 80 μm on both sides of a 30 μm-thick polyvinyl alcohol polarizing film (average polymerization degree 1700, average saponification degree 99 mol%, iodine staining, 4-fold stretching). The polarizing plate (the polyvinyl alcohol polarizing film was cut into 100 mm × 100 mm by tilting the direction of the stretching axis by 45 °) was used.

  On the other hand, a sample for measuring gel fraction and surface resistivity was prepared by using a polyethylene terephthalate (PET) film (thickness 38 μm) instead of the polarizing plate in the same manner as described above.

  Using the thus obtained polarizing plate with the pressure-sensitive adhesive layer or PET film with the pressure-sensitive adhesive layer, its physical properties [surface resistivity, gel fraction, durability (wet heat resistance test, heat cycle test), adhesive strength Were measured and evaluated according to the following methods. These results are also shown in Table 3 below.

[Gel fraction]
After the obtained PET film with the pressure-sensitive adhesive layer is cut into 40 × 40 mm, the release film is peeled off and the pressure-sensitive adhesive layer side is bonded to a 50 × 100 mm SUS mesh sheet (200 mesh), and then the SUS mesh sheet. The sample was wrapped from the center with respect to the longitudinal direction, and the sample was wrapped. Then, the gel fraction (%) was measured by the change in weight when immersed in a sealed container containing 250 g of toluene.

[Surface resistivity]
The obtained PET film with the pressure-sensitive adhesive layer was cut into a size of 40 × 40 mm, and this was left to stand for 3 hours under conditions of a temperature of 23 ° C. and a relative humidity of 65%, and then the release sheet was peeled off. About the adhesive layer after 10 to 20 seconds, the surface resistivity was measured using a resistivity meter (manufactured by Mitsubishi Chemical Corporation, Hiresta UP). In addition, it means that antistatic performance is so high that surface resistivity is small.

〔durability〕
The release sheet of the obtained polarizing plate with the pressure-sensitive adhesive layer was peeled off, and the pressure-sensitive adhesive layer side was pressed against a non-alkali glass plate (Corning 1737, manufactured by Corning) to bond the polarizing plate and the glass plate. Thereafter, autoclave treatment (50 ° C., 0.5 MPa, 20 minutes) was performed, and thereafter foaming, peeling, and light leakage phenomenon were evaluated in the following durability tests (wet heat resistance test, heat cycle test, heat resistance test).
For the heat resistance test only, the same sample was bonded to both the front and back surfaces so that the polarizing plate was crossed Nicol, and was used for light leakage observation.
* The test piece size is 10cm x 10cm in case of heat and moisture resistance.
* The test piece size is 20cm x 15cm for the heat resistance test.

〔An endurance test〕
(1) Moisture and heat resistance test 60 ° C., 90% R.D. H. Endurance test for 300 hours (2) Heat cycle test Endurance test for 300 cycles with the operation of leaving at −40 ° C. for 30 minutes and then leaving at 85 ° C. for 30 minutes as one cycle (3) Heat test 80 ° C. for 300 hours An endurance test

〔Evaluation criteria〕
(Foam)
A: Foam is hardly seen B: Foam is slightly seen C: Foam is seen a lot (peeling)
A: Peeling of less than 0.5 mm or generation of a lift mark B: Peeling of 0.5 mm or more and less than 10 mm, or generation of a lift mark C: Peeling of 10 mm or more, or lift of 10 mm or more Occurrence (light leakage)
Only the heat resistance test (3) was evaluated for light leakage.
A: Almost no light leakage B: Slight light leakage C: Large light leakage on 4 sides

〔Adhesive force〕
About the prepared polarizing plate with an adhesive layer, it cuts to width 25mm width, peels off a release film, presses the adhesive layer side to a non-alkali glass board (Corning company make, "Corning 1737"), and polarized light The plate and the glass plate were bonded together. Thereafter, autoclave treatment (50 ° C., 0.5 MPa, 20 minutes) was performed, and a 180 ° C. peel test was performed 24 hours later.

From the above results, the examples show excellent antistatic performance with a surface resistivity of 9 × 10 ¹¹ or less, and excellent durability, which is important when used as an adhesive for optical members. It can be seen that the durability is inferior in Comparative Examples 1 and 2 using an acrylic resin having a dispersity value greater than 7. Further, although the dispersion degree of the acrylic resin is 7 or less, Comparative Example 3 using the acrylic resin (A′-3) not containing an oxyalkylene structure is excellent in durability performance but inferior in antistatic performance. It turns out that it is a thing.

  From the above, it is important to use an acrylic resin that contains an oxyalkylene structure and has a dispersity of 7 or less in order to obtain a pressure-sensitive adhesive for optical members that is excellent in balance between antistatic performance and durability. I understand.

  The pressure-sensitive adhesive for optical members of the present invention is less likely to be charged with static electricity generated in each step, and has excellent adhesion between the optical laminate and the glass substrate even under high temperature and high humidity conditions. Since foaming and peeling do not occur between the glass substrate and the light leakage phenomenon caused by the contraction of the optical film can be suppressed, a liquid crystal display panel with excellent durability can be obtained, which is very useful. is there.

Claims (13)

  Adhesive composition containing an acrylic resin (A) having an oxyalkylene structure in the side chain, a weight average molecular weight of 200,000 to 3,000,000 and a dispersity of 7 or less, and an unsaturated group-containing compound (B) An adhesive for optical members, wherein [I] is crosslinked by at least one of active energy rays and heat. An acrylic resin (A) containing an oxyalkylene structure in the side chain, having a weight average molecular weight of 200,000 to 3,000,000 and a dispersity of 7 or less, contains an oxyalkylene structure represented by the following general formula (1) (meta 2. The pressure-sensitive adhesive for optical members according to claim 1, which is an acrylic resin obtained by copolymerizing a copolymer component containing an acrylic monomer (a1).

Here, X is an alkylene group, Y is an alkyl group or a phenyl group, R ₁ is a hydrogen atom or a methyl group, and n is an integer of 1 or more.   The pressure-sensitive adhesive for optical members according to claim 1 or 2, wherein the unsaturated group-containing compound (B) is at least one of a urethane (meth) acrylate compound (b1) and an ethylenically unsaturated monomer (b2).   Content of an unsaturated group containing compound (B) is 5-99 weight part with respect to 100 weight part of acrylic resin (A), The adhesion for optical members in any one of Claims 1-3 characterized by the above-mentioned. Agent.   X in general formula (1) is a C1-C10 alkylene group, Y is a C1-C15 alkyl group, n is 1-10, The adhesive for optical members in any one of Claims 2-4 .   The adhesive for optical members according to any one of claims 1 to 5, wherein the adhesive composition [I] contains a polymerization initiator (C).   The adhesive for optical members according to any one of claims 1 to 6, wherein the adhesive composition [I] contains a crosslinking agent (D).   The adhesive for optical members according to claim 1, wherein the adhesive composition [I] contains an antistatic agent (E).   The adhesive for optical members according to claim 1, wherein the adhesive composition [I] contains a silane coupling agent (F).   The adhesive for optical members according to any one of claims 1 to 9, wherein the adhesive resin composition [I] further contains an oxyalkylene structure-containing compound (G) that does not contain an unsaturated group.   An optical member is a polarizing plate, The adhesive for optical members in any one of Claims 1-10.   The optical member with an adhesive layer containing the laminated structure of the adhesive layer containing the adhesive for optical members in any one of Claims 1-11, and an optical member.   Active energy rays and / or heat containing an oxyalkylene structure-containing acrylic resin (A) having a weight average molecular weight of 200,000 to 3,000,000 and a dispersity of 7 or less, and an unsaturated group-containing compound (B) A pressure-sensitive adhesive composition for a curable optical member.