TW201720897A - Adhesive composition, adhesive layer, optical film having attached adhesive layer, optical member, and image display device - Google Patents

Abstract

The present invention pertains to an adhesive composition containing a rubber-based polymer (A) and a tackifier (B), wherein the rubber-based polymer (A) includes at least one rubber-based polymer selected from the group consisting of a styrene-based thermoplastic elastomer (A1) and an isobutylene-based polymer (A2) having a weight average molecular weight of 500,000 or greater. The rubber-based polymer includes at least one selected from the group consisting of a natural material-based tackifier (B1), a petroleum resin-based tackifier (B2) and hydrogenated products thereof, when including the styrene-based thermoplastic elastomer (A1); and includes at least one selected from the group consisting of a natural material-based tackifier (B1) and hydrogenated products thereof, when including the isobutylene-based polymer (A2). This adhesive composition has low moisture permeability, and is capable of forming an adhesive layer which, even in high-temperature environments, is durable enough not to suffer from problems such as delamination or peeling.

Description

Adhesive composition, adhesive layer, optical film with adhesive layer, optical member and image display device

TECHNICAL FIELD The present invention relates to an adhesive composition and an adhesive layer formed of the adhesive composition. Further, the present invention relates to an optical film comprising an adhesive layer formed of the above-mentioned adhesive layer on an optical film, and an optical member comprising the optical film with the adhesive layer. The invention further relates to an image display device comprising the optical film and/or optical member with the aforementioned adhesive layer.

Background Art In recent years, image display devices such as liquid crystal display devices have been increasingly required to be lighter and thinner, and various optical members such as a polarizing film used in video display devices are expected to be thinner and lighter.

For example, as a polarizing film, a single-sided protective polarizing film having a transparent protective film on one side of a polarizing member is known. Although such a single-sided protective polarizing film can be made thinner and lighter, the polarizer has a problem that it is not protected by a protective film, and is easily deteriorated by moisture or the like. In addition, in the case where the transparent protective film is thinned, the polarizer is similarly deteriorated by moisture or the like.

In addition, since the organic EL panel mounted on the organic EL (Electro Luminescence) display device is extremely weak in moisture and oxygen in the atmosphere, a barrier layer or an optical function with a barrier function is usually provided on the surface of the organic EL panel. With a film, it is sought to prevent moisture or the like from penetrating the adhesive layer (low moisture permeability).

As described above, various optical members used in the image display device are easily deteriorated by moisture or the like depending on the material, and are required to adhere the optical member to the adhesive layer of the article to be pressed. Does not penetrate moisture (low moisture permeability).

In the case of such a low moisture-permeable adhesive layer, for example, an adhesive composition is known which comprises, in a specific blending ratio, two types of isobutylene resins having different weight average molecular weights, and having a specific softening point. An adhesive composition of a hydrogenated petroleum resin (for example, refer to Patent Document 1). Further, a continuation sealing composition comprising a hydrogenated cyclic olefin polymer and a polyisobutylene resin having a specific weight average molecular weight (for example, see Patent Document 2).

PRIOR ART DOCUMENT PATENT DOCUMENT Patent Document 1: Japanese Patent No. 5416316 Specification Patent Document 2: JP-A-2007-197517

SUMMARY OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION The adhesive layer formed in the adhesive compositions of Patent Documents 1 and 2 is low in moisture permeability. However, if the storage test is carried out at a high temperature, problems such as floating or peeling may occur. The problem.

Accordingly, an object of the present invention is to provide an adhesive composition capable of forming an adhesive layer which has low moisture permeability and which has high durability against occurrence of defects such as floating or peeling even in a high temperature environment. Further, an object of the present invention is to provide an adhesive layer formed of the adhesive composition, an optical film provided with an adhesive layer of the adhesive layer, and an optical member including the optical film of the adhesive layer. Further, another object of the invention is to provide an image display device comprising one or more selected from the group consisting of an optical film comprising the adhesive layer and the optical member. Means to solve the problem

In order to solve the above problems, the present inventors have found out the following adhesive compositions and have completed the present invention.

That is, the present invention relates to an adhesive composition comprising a rubber-based polymer (A) and an adhesion-imparting agent (B), the adhesive composition characterized in that the rubber-based polymer (A) is selected from the group consisting of At least one rubber-based polymer of the group consisting of the styrene-based thermoplastic elastomer (A1) and the isobutylene-based polymer (A2), and the weight average molecular weight of the isobutylene-based polymer (A2) is 500,000 or more; When the rubber-based polymer (A) contains the styrene-based thermoplastic elastomer (A1), the adhesion-imparting agent (B) is selected from the group consisting of a natural-material adhesion-imparting agent (B1) and a petroleum resin-based adhesion-imparting agent (B2). And at least one of the adhesion-imparting agents in the group of the hydrides; and the rubber-based polymer (A) comprises the isobutylene-based polymer (A2), wherein the adhesion-imparting agent (B) is selected from the group consisting of At least one of the adhesion-imparting agents in the group consisting of the natural substance adhesion-imparting agent (B1) and the hydrides.

The adhesion-imparting agent (B) preferably contains a natural substance adhesion-imparting agent (B1). In the above-mentioned natural substance adhesion-imparting agent (B1), at least one selected from the group consisting of an adhesion-imparting agent containing a terpene skeleton, an adhesion-imparting agent containing a rosin skeleton, and the like. Kind.

The moisture permeability of the adhesive layer having a thickness of 50 μm formed of the above-mentioned adhesive composition at 40 ° C and 92% RH is preferably 100 g / (m ² · day) or less.

The above-mentioned adhesion-imparting agent (B) is preferably a hydride.

The softening point of the above-mentioned adhesion-imparting agent (B) is preferably 100 ° C or more.

The above-mentioned natural substance adhesion-imparting agent (B1) preferably contains a cyclohexanol skeleton.

The content of the adhesion-imparting agent (B) is preferably 1 part by weight or more based on 100 parts by weight of the rubber-based polymer (A).

The adhesive composition preferably further contains at least one softener (C) selected from the group consisting of a polyisobutylene compound (C1) and a polyisoprene compound (C2), and the polyisobutylene The weight average molecular weight of the compound (C1) is 50,000 or less, and the weight average molecular weight of the polyisoprene-based compound (C2) is 50,000 or less.

The content of the softener (C) is preferably 1 part by weight or more based on 100 parts by weight of the rubber-based polymer (A).

Further, the present invention relates to an adhesive layer characterized by being formed of the aforementioned adhesive composition.

Further, the present invention relates to an optical film having an adhesive layer characterized by comprising an optical film and the above-mentioned adhesive layer provided on the optical film.

The optical film is preferably a polarizing film having a transparent protective film on at least one side of the polarizing member.

The polarizing film is preferably a single-sided protective polarizing film having a transparent protective film on only one side of the polarizing member, and the adhesive layer should be laminated on the side of the polarizing member which does not have the transparent protective film.

The aforementioned optical film may be a luminance improving film.

Further, the present invention relates to an optical member characterized by comprising the optical film and the brightness enhancing film of the above-mentioned adhesive layer, and an optical member characterized by comprising the above-mentioned adhesive layer and at 40 ° C, 92% RH. moisture permeability of 1g / (m ² · day) or less of the film.

The present invention further relates to an image display device comprising at least one selected from the group consisting of an optical film comprising the adhesive layer and the optical member. Effect of the invention

By adding a specific adhesion-imparting agent (B) to a specific rubber-based polymer (A), the adhesive composition of the present invention can maintain a low moisture permeability while suppressing a problem in a high-temperature environment ( Float or peeling, etc. occur (high durability).

Moreover, the present invention can provide an optical film, an optical member, and an optically reliable image display device which are excellent in durability in a high-temperature environment and excellent in low moisture permeability.

The adhesive composition of the present invention contains the rubber-based polymer (A) and the adhesion-imparting agent (B), and the adhesive composition is characterized in that the rubber-based polymer (A) comprising at least one rubber-based polymer selected from the group consisting of a styrene-based thermoplastic elastomer (A1) and an isobutylene-based polymer (A2), and the weight of the isobutylene-based polymer (A2) When the rubber-based polymer (A) contains the styrene-based thermoplastic elastomer (A1), the adhesion-imparting agent (B) is selected from the group consisting of a natural substance-based adhesion-imparting agent (B1), At least one type of adhesion-imparting agent in the group consisting of the petroleum resin-based adhesion-imparting agent (B2) and the hydrides; and the rubber-based polymer (A) containing the isobutylene-based polymer (A2), the adhesion-providing The agent (B) contains at least one type of adhesion-imparting agent selected from the group consisting of the natural substance adhesion-imparting agent (B1) and the hydride.

(1) Rubber-based polymer (A) The rubber-based polymer (A) used in the present invention is a polymer which exhibits rubber elasticity in a temperature range near room temperature. Specifically, it is an isobutylene-based polymer (A2) selected from the group consisting of a styrene-based thermoplastic elastomer (A1) and a weight average molecular weight (Mw) of 500,000 or more (hereinafter, also referred to as "isobutylene polymerization" One or more rubber-based polymers in the group of the composition (A2)").

The styrene-based thermoplastic elastomer (A1) may, for example, be a styrene-ethylene-butylene-styrene block copolymer (SEBS) or a styrene-isoprene-styrene block copolymer. (SIS), styrene-butadiene-styrene block copolymer (SBS), styrene-ethylene-propylene-styrene block copolymer (SEPS, hydride of SIS), styrene-ethylene-propylene Block copolymer (SEP, hydride of styrene-isoprene block copolymer), styrene-isobutylene-styrene block copolymer (SIBS), styrene-butadiene rubber (SBR), etc. A vinyl-based block copolymer. Among these, from the viewpoint of having a polystyrene block at both ends of the molecule and having high cohesive force as a polymer, a styrene-ethylene-propylene-styrene block copolymer (SEPS, SIS) is preferred. Hydride), styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-isobutylene-styrene block copolymer (SIBS).

For the styrene-based thermoplastic elastomer (A1), for example, SEPTON, HYBRAR manufactured by KURARAY, Tuftec manufactured by Asahi Kasei Chemical Co., Ltd., SIBSTAR manufactured by Kaneka, etc. can be used. Sale.

The weight average molecular weight of the styrene-based thermoplastic elastomer (A1) is not particularly limited, but is preferably from 50,000 to 500,000, more preferably from 50,000 to 300,000, still more preferably from 50,000 to 25 About 10,000. The weight average molecular weight of the styrene-based thermoplastic elastomer (A1) is in the above range, and it is preferable because the cohesive force and viscoelasticity of the polymer can be achieved.

The styrene content in the styrene-based thermoplastic elastomer (A1) is not particularly limited, and is, for example, preferably about 5 to 70% by weight, more preferably about 5 to 40% by weight, still more preferably 10 to 20% by weight. %about. Since the styrene content in the styrene-based thermoplastic elastomer (A1) is in the above range, it is preferable to maintain the cohesive force due to the styrene portion while securing the viscoelasticity due to the soft segment.

The isobutylene polymer (A2) includes isobutylene as a constituent monomer and has a weight average molecular weight of 500,000 or more. The isobutylene polymer (A2) may be a homopolymer of isobutylene (polyisobutylene, PIB) or a copolymer having isobutylene as a main monomer (ie, more than 50 mol% of isobutylene). The proportion of the copolymer is copolymerized). As such a copolymer, for example, a copolymer of isobutylene and n-butene, a copolymer of isobutylene and isoprene (for example, ordinary butyl rubber, chlorobutyl rubber, bromobutyl rubber) may be mentioned. And a butyl rubber such as a partially crosslinked butyl rubber), such a sulfide and a modified product (for example, those modified by a functional group such as a hydroxyl group, a carboxyl group, an amine group or an epoxy group). Among these, polyisobutylene (PIB) is preferred from the viewpoint that the main chain does not contain a double bond and the weather resistance is excellent.

For the isobutylene polymer (A2), for example, a commercially available product such as OPPANOL manufactured by BASF Corporation can be used.

The weight average molecular weight of the isobutylene polymer (A2) is 500,000 or more, preferably 600,000 or more, and more preferably 700,000 or more. Further, the upper limit 重量 of the weight average molecular weight is not particularly limited, but is preferably 5,000,000 or less, more preferably 3,000,000 or less, still more preferably 2,000,000 or less. By setting the weight average molecular weight of the isobutylene polymer (A2) to 500,000 or more, it is possible to form an adhesive composition which is more excellent in durability during storage at a high temperature.

The content of the rubber-based polymer (A) is not particularly limited, and the total solid content of the adhesive composition is preferably 30% by weight or more, more preferably 40% by weight or more, and still more preferably 50% by weight or more. It is particularly preferably 60% by weight or more. The upper limit of the content of the rubber-based polymer (A) is not particularly limited, but is preferably 95% by weight or less, and more preferably 90% by weight or less.

In addition, when the rubber-based polymer (A) contains the styrene-based thermoplastic elastomer (A1), the content of the total solid content of the adhesive composition is preferably 30% by weight or more, and more preferably It is 35 wt% or more, and more preferably 40 wt% or more. In addition, the upper limit is not particularly limited, and is, for example, preferably about 90% by weight or less, more preferably about 70% by weight or less.

In addition, when the rubber-based polymer (A) contains the isobutylene-based polymer (A2), the total solid content of the adhesive composition is preferably 60% by weight or more, and more preferably 70% by weight. More preferably, it is 80% by weight or more. In addition, the upper limit is not particularly limited, and is, for example, preferably about 98% by weight or less, more preferably about 90% by weight or less.

Moreover, the adhesive composition of the present invention may contain a rubber-based polymer other than the rubber-based polymer (A). Specifically, butyl rubber (IIR), butadiene rubber (BR), acrylonitrile-butadiene rubber (NBR), EPR (binary ethylene-propylene rubber), EPT (ternary ethylene) - propylene rubber), acrylic rubber, urethane rubber, polyurethane thermoplastic elastomer; polyester thermoplastic elastomer; polymer blend of polypropylene and EPT (ternary ethylene-propylene rubber) The blend of the compound or the like is a thermoplastic elastomer or the like. The amount of the rubber-based polymer (A) is preferably about 10 parts by weight or less based on 100 parts by weight of the rubber-based polymer (A).

(2) Adhesive-imparting agent (B) The adhesive-imparting agent (B) used in the present invention is exemplified by a natural-type adhesion-imparting agent (B1), a petroleum-based adhesion-imparting agent (B2), and the like. Things. These adhesion-imparting agents (B) are selected in accordance with the rubber-based polymer (A). In other words, when the styrene-based thermoplastic elastomer (A1) is used, a group selected from the group consisting of a natural substance adhesion-imparting agent (B1), a petroleum resin-based adhesion-imparting agent (B2), and the like can be used. At least one of the groups is used as the adhesion-imparting agent (B). On the other hand, when the isobutylene polymer (A2) is used, at least one selected from the group consisting of the natural substance adhesion-imparting agent (B1) and the hydrides may be used as the adhesion. Agent (B). The adhesive composition of the present invention can form an adhesive layer having high adhesion to various substrates and high durability even in a high temperature environment by including the adhesion-imparting agent (B).

In the present invention, since the rubber-based polymer (A) is used, the adhesion-imparting agent (B1) is a natural substance-based adhesion-imparting agent (B1) such as a terpene-containing phenol having a hydroxyl group and a high moisture permeability. can use. In other words, in the present invention, by using a specific rubber-based polymer (A) and a specific adhesive-imparting agent (B), it is possible to improve durability in a high-temperature environment while maintaining low moisture permeability.

The natural substance adhesion-imparting agent (B1) is, for example, an adhesion-imparting agent containing a terpene skeleton, an adhesion-imparting agent containing a rosin skeleton, and the like. In addition, in the following description, the description about the natural substance adhesion imparting agent (B1) contains the concept of the hydride.

Examples of the adhesion-imparting agent containing a terpene skeleton include a terpene polymer such as an α-pinene polymer, a β-pinene polymer, and a dipentene polymer; A modified terpene resin obtained by modifying a polymer (phenol modification, styrene modification, aromatic modification, hydrogenation modification, hydrocarbon modification, etc.). Examples of the modified terpene resin include a terpene phenol resin, a styrene-modified terpene resin, an aromatic modified terpene resin, a hydrogenated terpene resin, and the like. Examples of the hydrogenated terpene resin referred to herein include a hydride of a terpene polymer and other modified terpene resins and a hydrogenated product of a terpene phenol resin. Among these, a hydride of a terpene phenol resin is preferred from the viewpoint of compatibility with a rubber-based adhesive and adhesion characteristics.

The rosin-containing adhesive-imparting agent may, for example, be a rosin resin, a polymerized rosin resin, a hydrogenated rosin resin, a rosin ester resin, a hydrogenated rosin ester resin, a rosin phenol resin or the like. Specifically, a rubber rosin may be used ( Unmodified rosin (raw rosin) such as gum rosin), wood rosin, tall oil rosin, modified rosin which is hydrogenated, disproportionated, polymerized, and other chemically modified; Derivatives of etc.

The petroleum-based resin-based adhesion-imparting agent (B2) may, for example, be an aromatic petroleum resin, an aliphatic petroleum resin, an alicyclic petroleum resin (aliphatic cyclic petroleum resin), or an aliphatic or aromatic A petroleum resin, an aliphatic/alicyclic petroleum resin, a hydrogenated petroleum resin, a coumarone resin, a coumarone-indene resin, or the like. The aromatic petroleum resin may, for example, be a vinyl-containing aromatic hydrocarbon having a carbon number of 8 to 10 (styrene, o-vinyltoluene, m-vinyltoluene, p-vinyltoluene, α). A polymer obtained by using only one type or two or more types, such as methyl styrene, β-methyl styrene, hydrazine, and methyl hydrazine. Among these, an aromatic petroleum resin (so-called "C9-based petroleum resin") which can be obtained from a fraction such as vinyl toluene or hydrazine (so-called "C9 petroleum fraction") is preferable. In addition, examples of the aliphatic petroleum resin include olefins having 4 to 5 carbon atoms and olefins such as butene-1, isobutylene and pentene-1; butadiene and piperylene; A polymer obtained by using only one type or two or more types of diene (such as 1,3-pentadiene) and isoprene. Among these, it is preferably an aliphatic system which can be obtained from fractions such as butadiene, piperylene, and isoprene (so-called "C4 petroleum fraction" and "C5 petroleum fraction"). Petroleum resin (so-called "C4 petroleum resin" and "C5 petroleum resin"). Further, the alicyclic petroleum resin may be cyclized and dimerized, for example, by an aliphatic petroleum resin (so-called "C4 petroleum resin" or "C5 petroleum resin"). An alicyclic hydrocarbon resin obtained by polymerization, a cyclic diene compound (cyclopentadiene, dicyclopentadiene, ethylidene norbornene, dipentene, ethylene bicycloheptene, A polymer of vinylcycloheptene, tetrahydroanthracene, vinylcyclohexene, limonene or the like, or a hydrogenated product thereof, hydrogenated an aromatic ring of the above aromatic hydrocarbon resin or the following aliphatic/aromatic petroleum resin An alicyclic hydrocarbon resin or the like. Further, the aliphatic/aromatic petroleum resin may, for example, be a styrene-olefin copolymer. The aliphatic/aromatic petroleum resin may be a so-called "C5/C9 copolymerized petroleum resin" or the like. In the following description, the description of the petroleum resin-based adhesion-imparting agent (B2) includes the concept of the hydride.

Among the above-mentioned adhesion-imparting agent (B), the natural-type adhesion-imparting agent (B1) is, for example, a Clearon series manufactured by Yasuhara Chemical Co., Ltd., a Polyster series, and a Super by Arakawa Chemical Industry Co., Ltd. For the petroleum resin-based adhesion-imparting agent (B2), for example, a commercially available product such as the Arkon series manufactured by Arakawa Chemical Industries Co., Ltd. can be used.

When the above-mentioned adhesion-imparting agent (B) is a hydride, the hydrogenation may be a partially hydrogenated partial hydride or a complete hydride in which all of the double bonds in the compound are hydrogenated. In the present invention, from the viewpoint of adhesive properties, weather resistance and color tone, a fully hydride is preferred.

As the adhesion-imparting agent (B), a natural-system adhesion-imparting agent (B1) can be suitably used. From the viewpoint of adhesion characteristics, the natural substance adhesion imparting agent (B1) is preferred because it contains a cyclohexanol skeleton. Although this detailed principle is not clear, it is considered that the cyclohexanol skeleton is more compatible with the base polymer, that is, the rubber-based polymer, than the phenol skeleton. The adhesion-imparting agent containing a cyclohexanol skeleton is, for example, preferably a hydrogenated product such as a terpene phenol resin or a rosin phenol resin, more preferably a completely hydrogenated product such as a terpene phenol resin or a rosin phenol resin.

The softening point (softening temperature) of the adhesion-imparting agent (B) is not particularly limited, and is, for example, preferably about 80 ° C or higher, more preferably about 100 ° C or higher. Since the softening point of the adhesion-imparting agent (B) is 80 ° C or more, the adhesion-imparting agent can maintain the adhesive property without softening even at a high temperature. The upper limit of the softening point of the adhesion-imparting agent (B) is not particularly limited, but if the softening point is too high, the molecular weight becomes higher, the compatibility is deteriorated, and a problem such as whitening occurs. Preferably, it is about 200 ° C or less, preferably about 180 ° C or less. Further, the softening point of the adhesion-imparting resin referred to herein is defined as the enthalpy measured by the softening point test method (ring and ball method) prescribed in any one of JIS K5902 and JIS K2207.

The weight average molecular weight of the adhesion-imparting agent (B) is not particularly limited, but is preferably 50,000 or less, preferably 30,000 or less, more preferably 10,000 or less, still more preferably 8,000 or less, and particularly preferably 5,000 or less. In addition, the lower limit 重量 of the weight average molecular weight of the adhesion-imparting agent (B) is not particularly limited, but is preferably 500 or more, more preferably 1,000 or more, still more preferably 2,000 or more. Since the weight average molecular weight of the adhesion-imparting agent (B) is in the above range, compatibility with a rubber-based polymer is good, and whitening or the like is not caused, which is preferable.

The amount of the adhesion-imparting agent (B) to be added is preferably 250 parts by weight or less, more preferably 200 parts by weight or less, even more preferably 150 parts by weight or less, based on 100 parts by weight of the rubber-based polymer (A). When the natural-type adhesion-imparting agent (B1) is used as the adhesion-imparting agent (B), the amount of the natural-type adhesion-imparting agent (B1) added is preferably 100 parts by weight based on 100 parts by weight of the rubber-based polymer (A). It is 100 parts by weight or less, more preferably 85 parts by weight or less, further preferably 50 parts by weight or less, and particularly preferably 45 parts by weight or less. Further, the lower limit 添加 of the amount of the adhesion-imparting agent (B) to be added is not particularly limited, but is preferably 1 part by weight or more, and more preferably 5 parts by weight or more. By using the amount of the adhesion-imparting agent (B) in the above range, it is preferable because the adhesion characteristics can be improved. In addition, if the amount of the adhesion-imparting agent (B) is more than the above range and it is added in a large amount, the cohesive force of the adhesive tends to be lowered, which is not preferable.

When the rubber-based polymer (A) contains the styrene-based thermoplastic elastomer (A1), the natural-based adhesion-imparting agent (B1) and/or the petroleum-based adhesion-imparting agent (B2) may be used as the adhesion. The agent (B) is given. The amount of the natural substance-based adhesion-imparting agent (B1) to be added is preferably 100 parts by weight or less, more preferably 85 parts by weight or less, even more preferably 100 parts by weight of the styrene-based thermoplastic elastomer (A1). 70 parts by weight or less, particularly preferably 45 parts by weight or less. In addition, the lower limit of the amount of the natural substance adhesion-imparting agent (B1) to be added is not particularly limited, but is preferably 0.5 parts by weight or more, more preferably 1 part by weight or more, still more preferably 10 parts by weight or more, particularly preferably 20 parts by weight or more. In addition, when the petroleum resin-based adhesion-imparting agent (B2) is contained as the adhesion-imparting agent (B), the amount of the natural-system adhesion-imparting agent (B1) may be 0 parts by weight.

On the other hand, the amount of the petroleum resin-based adhesion-imparting agent (B2) to be added is preferably 150 parts by weight or less, more preferably 100 parts by weight or less, based on 100 parts by weight of the styrene-based thermoplastic elastomer (A1). It is preferably 70 parts by weight or less, more preferably 50 parts by weight, still more preferably 30 parts by weight. Further, the lower limit of the amount of the petroleum resin-based adhesion-imparting agent (B2) to be added is not particularly limited, but is preferably 0.5 part by weight or more, more preferably 1 part by weight or more, still more preferably 5 parts by weight or more, and still more preferably 10 or more. More than the weight. In addition, when the natural substance adhesion-imparting agent (B1) is contained as the adhesion-imparting agent (B), the amount of the petroleum-based adhesion-imparting agent (B2) added may be 0 part by weight.

When the rubber-based polymer (A) contains the styrene-based thermoplastic elastomer (A1), the natural-type adhesion-imparting agent (B1) and the petroleum-based adhesion-imparting agent (B2) are used as the adhesion-imparting agent (B). The situation is better. From the viewpoint of the compatibility with the styrene portion, it is preferred to use a petroleum resin-based adhesion-imparting agent (B2) in addition to the above-mentioned natural-system adhesion-imparting agent (B1). In the above-mentioned combination, the amount of the natural substance adhesion-imparting agent (B1) to be added is preferably 0.5 to 150 parts by weight, and more preferably 0.5 to 100 parts by weight of the styrene-based thermoplastic elastomer (A1). The amount of the petroleum resin-based adhesion-imparting agent (B2) to be added is preferably from 0.5 to 150 parts by weight, more preferably from 0.5 to 100 parts by weight, per 100 parts by weight.

In addition, when the rubber-based polymer (A) contains the isobutylene-based polymer (A2), the natural-type adhesion-imparting agent (B1) can be used as the adhesion-imparting agent (B). The amount of the natural substance adhesion-imparting agent (B1) to be added is preferably 40 parts by weight or less, more preferably 30 parts by weight or less, even more preferably 20 parts by weight, based on 100 parts by weight of the above-mentioned isobutylene polymer (A2). The following. Further, the lower limit of the amount of the adhesion-imparting agent (B) to be added is not particularly limited, but is preferably 0.5 parts by weight or more, more preferably 1 part by weight or more, and still more preferably 5 parts by weight or more. In addition, when the rubber-based polymer (A) contains the isobutylene polymer (A2), the petroleum resin-based adhesion-imparting agent (B2) may be arbitrarily added to the adhesive composition, but it is relative to the isobutylene-based polymer (A2). 100 parts by weight, the amount thereof is preferably 40 parts by weight or less, more preferably 20 parts by weight or less, or 0 parts by weight.

Further, the adhesive composition of the present invention may be added with an adhesive agent other than the natural substance adhesion-imparting agent (B1) or the petroleum resin-based adhesion-imparting agent (B2). However, the amount of the other adhesion-imparting agent added is preferably 100 parts by weight or less based on 100 parts by weight of the rubber-based polymer (A).

(3) Other additives The additives other than the above may be added to the adhesive composition of the present invention within the range not impairing the effects of the present invention. The additive is not particularly limited, and a softener (C) is preferably added from the viewpoint of adhesion characteristics.

Depending on the type of the adhesion-imparting agent (B), the elastic modulus of the adhesive layer in the low temperature region may increase, and for example, the specific characteristics such as the impact resistance may be deteriorated. In such a situation, the softening agent (C) is used in the adhesive composition, and the elastic modulus of the rubber-based polymer (A) can be lowered by the plasticizing effect thereof. As a result, even if the above-mentioned adhesion-imparting agent is used ( B) It is preferable because the above-mentioned defects can be suppressed.

The softener (C) is selected from the group consisting of a polyisobutylene compound (C1) having a weight average molecular weight of 50,000 or less and a polyisoprene compound having a weight average molecular weight of 50,000 or less (C2). At least one softener in the group formed.

The weight average molecular weight of the softener (C) is 50,000 or less, more preferably 40,000 or less. Further, the lower limit 重量 of the weight average molecular weight of the softener (C) is not particularly limited, but is preferably 500 or more, and more preferably 1,000 or more. When the weight average molecular weight of the softener (C) is in the above range, it is possible to prevent a decrease in the cohesive force due to an excessively small molecular weight, and it is possible to prevent the molecular weight from becoming too large to act as a softener. .

The polyisobutylene compound (C1) may be a compound composed only of isobutylene (polyisobutylene) or a copolymer having isobutylene as a main monomer (that is, a ratio of isobutylene to more than 50 mol%). Copolymers included). As such a copolymer, for example, a copolymer of isobutylene and n-butene, a copolymer of isobutylene and isoprene (for example, ordinary butyl rubber, chlorobutyl rubber, bromobutyl rubber) may be mentioned. And a butyl rubber such as a partially crosslinked butyl rubber), such a sulfide and a modified product (for example, modified by a functional group such as a hydroxyl group, a carboxyl group, an amine group or an epoxy group). Among these, polyisobutylene is preferred because it does not contain a double bond in the main chain and is excellent in weather resistance.

The polyisoprene-based compound (C2) may be a compound composed only of isoprene (polyisoprene) or a copolymer having isoprene as a main monomer ( That is, a copolymer of isoprene in a ratio of more than 50 mol%). Specific examples of such a copolymer include butadiene-isoprene-styrene random copolymer, isoprene-styrene random copolymer, hydrogenated polyisoprene, and the like. . Among these, hydrogenated polyisoprene is preferred from the viewpoint of the plasticizing effect on the rubber-based polymer.

For the softener (C), for example, commercially available products such as HV-300 manufactured by JX Nippon Mining & Energy Co., Ltd., and Kuraprene LIR-200 manufactured by Kuraray Co., Ltd. can be used.

In addition, the amount of the softening agent (C) is not particularly limited, but is preferably 50 parts by weight or less, more preferably 30 parts by weight or less, more preferably 100 parts by weight or less, more preferably 100 parts by weight of the rubber-based polymer (A). It is 25 parts by weight or less. Further, the lower limit of the amount of the softener (C) to be added is not particularly limited, but is preferably 0 parts by weight or more, more preferably 1 part by weight or more, still more preferably 5 parts by weight or more.

Further, in the above-described adhesive composition, an organic solvent can be added as a diluent. The diluent is not particularly limited, and examples thereof include toluene, xylene, and dimethyl ether. These may be used alone or in combination of two or more. Among these, toluene is preferred.

Although the amount of the diluent to be added is not particularly limited, it is preferably added in an amount of about 50 to 95% by weight in the adhesive composition, more preferably about 70 to 90% by weight. Since the amount of the diluent to be added is in the above range, it is preferably from the viewpoint of coatability to a support or the like.

In the above adhesive composition, any appropriate additive may be further included. Specific examples of the additive include a crosslinking agent (for example, a polyisocyanate, an epoxy compound, an alkyl etherified melamine compound, etc.), a filler, an anti-aging agent, and an ultraviolet absorber. The type, combination, addition amount, and the like of the additive to be added to the adhesive composition can be appropriately set in accordance with the purpose. The content (total amount) of the above-mentioned additive in the adhesive composition is preferably 30% by weight or less, more preferably 20% by weight or less, still more preferably 10% by weight or less.

2. Adhesive Layer The adhesive layer of the present invention is characterized in that it is formed of the aforementioned adhesive composition.

The method for producing the pressure-sensitive adhesive layer of the present invention is not particularly limited, and the pressure-sensitive adhesive layer can be formed by applying the pressure-sensitive adhesive composition to various supports or the like and removing the solvent by heat drying or the like.

As the coating method of the adhesive composition, various methods can be used. Specifically, for example, a roll coating method, a contact top coat coating method, a gravure coating method, a reverse roll coating method, a roll brushing method, a spray coating method, a dip roll coating method, a bar coating method, and the like, A blade coating method, a pneumatic blade coating method, a curtain coating method, a lip-mouth coating method, an extrusion coating method by a die coater or the like.

The heat drying temperature is preferably from about 30 ° C to about 200 ° C, more preferably from 40 ° C to 180 ° C, still more preferably from 80 ° C to 150 ° C. By setting the heating temperature to the above range, an adhesive layer having excellent adhesive properties can be obtained. The drying time can be carried out in an appropriate and appropriate time. The drying time is preferably from about 5 seconds to about 20 minutes, more preferably from 30 seconds to 10 minutes, still more preferably from 1 minute to 8 minutes.

For the aforementioned support, for example, a peel-treated sheet (separator) can be used.

The constituent material of the separator may, for example, be a plastic film such as polyethylene, polypropylene, polyethylene terephthalate or polyester film, or a porous material such as paper, cloth or non-woven fabric, or a mesh. (net), a foamed sheet, a metal foil, and a suitable thin leaf body such as these laminates, a plastic film can be suitably used from the viewpoint of excellent surface smoothness.

The plastic film may, for example, be a polyethylene film, a polypropylene film, a polybutene film, a polybutadiene film, a polymethylpentene film, a polyvinyl chloride film, a vinyl chloride copolymer film, or a poly A polyethylene terephthalate film, a polybutylene terephthalate film, a polyurethane film, an ethylene-vinyl acetate copolymer film, or the like.

The thickness of the separator is usually 5 to 200 μm, preferably about 5 to 100 μm. The separator may be subjected to mold release, antifouling treatment, coating type, and kneading by a polyfluorene-based, fluorine-based, long-chain alkyl-based or fatty acid-amine-based release agent, cerium oxide powder, or the like. Antistatic treatment such as type and evaporation. In particular, by appropriately performing a release treatment such as polyoxynitridation treatment, long-chain alkyl treatment, or fluorine treatment on the surface of the separator, the peeling property from the pressure-sensitive adhesive layer can be further improved.

The thickness of the pressure-sensitive adhesive layer of the present invention is not particularly limited, but may be appropriately set depending on the application, and is preferably 50 μm or less, more preferably 30 μm or less, and still more preferably 20 μm or less. Further, the lower limit 厚度 of the thickness of the pressure-sensitive adhesive layer is not particularly limited, but is preferably 1 μm or more, and more preferably 5 μm or more from the viewpoint of durability.

The moisture permeability of the pressure-sensitive adhesive layer is not particularly limited, but is preferably 100 g/(m ² · 24 h) or less, more preferably 60 g / (m ² · 24 h) or less, and still more preferably 50 g / (m ² · 24h) or less, more preferably 30g/(m ² · 24h) or less, and particularly preferably 20g/(m ² · 24h) or less. Further, the lower limit of the moisture permeability is not particularly limited, and it is preferable that the water vapor is not completely penetrated (that is, 0 g/(m ² · 24 h)). When the moisture permeability of the pressure-sensitive adhesive layer is in the above range, when the pressure-sensitive adhesive layer is applied to an optical film such as a polarizing film, it is possible to suppress the transfer of moisture to the optical film, and it is possible to suppress deterioration of the optical film due to moisture, and the like. . The moisture permeability is a water vapor transmission rate (water permeability) at 40 ° C and 92% RH when the thickness of the adhesive layer is 50 μm, and the measurement method can be measured by the method described in the examples.

3. Optical film with an adhesive layer The optical film with an adhesive layer of the present invention is characterized by having an optical film and the aforementioned adhesive layer provided on the optical film.

In the method of forming an adhesive layer on the optical film, the adhesive layer can be formed on the optical film by applying the above-described adhesive composition on the optical film, removing the solvent by heat drying or the like. Further, as described above, an adhesive layer can be formed on a support or the like, and the adhesive layer can be transferred onto an optical film to form an optical film with an adhesive layer. In this case, the release-treated sheet can be used as a separator of an optical film with an adhesive layer, which can be used for the production of the optical film with the adhesive layer, and the process surface can be simplified.

The type of the optical film used in the formation of various image display devices such as a liquid crystal display device is not particularly limited. For example, a polarizing film can be mentioned as an optical film. The polarizing film is generally used in the case where the polarizing member has a transparent protective film on one side or both sides. In the present invention, from the viewpoint of thinning, a one-side protective polarizing film is preferable.

The polarizing member is not particularly limited, and various polarizing members can be used. The polarizing member is, for example, a dichroic substance which adsorbs iodine and a dichroic dye to a polyvinyl alcohol-based film, a partially acetalized polyvinyl alcohol-based film, or an ethylene/vinyl acetate copolymer system. A hydrophilic polymer film such as a partially saponified film, which is uniaxially stretched, a polyether-based alignment film such as a dehydrated material of polyvinyl alcohol, and a dehydrochlorinated product of polyvinyl chloride. Among these, a polarizer comprising a polyvinyl alcohol-based film and a dichroic material such as iodine is suitable. The thickness of the polarizers is not particularly limited, but is generally about 5 to 80 μm.

A polarizing member obtained by dyeing a polyvinyl alcohol-based film with iodine and uniaxially stretching, for example, can be dyed by immersing polyvinyl alcohol in an aqueous solution of iodine, and extending to 3 to 7 times the original length. Production. It may also be immersed in an aqueous solution such as potassium iodide which may contain boric acid, zinc sulfate, zinc chloride or the like as needed. Further, the polyvinyl alcohol-based film may be further immersed in water and washed with water before the dyeing. By washing the polyvinyl alcohol-based film with water, the stain and the anti-caking agent can be washed on the surface of the polyvinyl alcohol-based film, and the polyvinyl alcohol-based film is swollen to prevent uneven dyeing. Uneven effect. The extension may be carried out after dyeing with iodine, or may be extended while dyeing, or may be first extended and then dyed with iodine. It is also possible to carry out stretching in an aqueous solution or a water bath such as boric acid or potassium iodide.

Further, from the viewpoint of film formation, a thin polarizer having a thickness of 10 μm or less is preferably used. From the viewpoint of thinning, the thickness is preferably from 1 to 7 μm. Such a thin polarizer is preferable because it has a small thickness unevenness, is excellent in visibility, and has a small dimensional change, and is excellent in durability, and can also be thinned as a thickness of a polarizing film.

The thin-type polarizing member is exemplified by Japanese Laid-Open Patent Publication No. Sho 51-069644, Japanese Patent Application Laid-Open No. 2000-338329, and No. 2010/100917. A thin polarizing film described in Japanese Laid-Open Patent Publication No. H07-73563. These thin polarizing films can be obtained by a method comprising the steps of: stretching a polyvinyl alcohol-based resin (hereinafter also referred to as PVA-based resin) layer and a resin substrate for stretching in a state of being laminated, and dyeing step. In the case of this method, even if the PVA-based resin layer is thin, it can be stretched without being defective (breakage due to elongation, etc.) by the resin substrate for stretching.

In the method of the step of performing the step of stretching and the step of dyeing in the state in which the layered body is stretched, the thin polarizing film is preferably formed at a high magnification and can improve the polarizing performance. The process of the step-by-step process is carried out in an aqueous solution of boric acid, as described in the specification of the International Publication No. 2010/100917, or the Japanese Patent Publication No. Hei. It is also obtained by the method including the following steps: assisting in air extension before extending in a boric acid aqueous solution described in JP-A-2014-059328 and JP-A-2012-073563 A step of.

The material for forming the transparent protective film provided on one surface or both surfaces of the polarizing member is preferably excellent in transparency, mechanical strength, thermal stability, moisture resistance, and isotropic properties. For example, polyester polymers such as polyethylene terephthalate and polyethylene naphthalate, cellulose polymers such as cellulose diacetate and triacetyl cellulose, and polymethyl An acrylic polymer such as methyl acrylate, a styrene polymer such as polystyrene or an acrylonitrile/styrene copolymer (AS resin), or a polycarbonate polymer. Further, polyethylene, polypropylene, polyolefin having a ring system or a norbornene structure, a polyolefin polymer such as an ethylene/propylene copolymer, a vinyl chloride polymer, a nylon, and an aromatic resin may also be mentioned. A guanamine-based polymer such as polyamine, a quinone-based polymer, a fluorene-based polymer, a polyether fluorene-based polymer, a polyetheretherketone-based polymer, a polyphenylene sulfide-based polymer, or a vinyl alcohol-based polymer , a vinylidene chloride-based polymer, a vinyl butyral polymer, an aryl ester polymer, a polyoxymethylene polymer, an epoxy polymer, or a blend of the foregoing polymers The substance or the like is exemplified as a polymer which forms the aforementioned transparent protective film. The transparent protective film may be formed as a cured layer of a thermosetting type or an ultraviolet curable resin such as an acrylic type, an urethane type, an urethane type, an epoxy type or a polyoxymethylene type. When a protective film is provided on both sides of the polarizing member, a protective film made of the same polymer material may be used in the front surface, and a protective film composed of a different polymer material or the like may be used.

The thickness of the protective film can be appropriately determined, but it is generally about 1 to 500 μm due to workability and film properties such as strength and workability.

The polarizer and the protective film are usually adhered to each other through a water-based adhesive or the like. The water-based adhesive may, for example, be an isocyanate-based adhesive, a polyvinyl alcohol-based adhesive, a gelatin-based adhesive, a vinyl-based latex, an aqueous polyurethane, or an aqueous polyester. In addition to the above, examples of the adhesive for the polarizer and the transparent protective film include an ultraviolet curable adhesive, an electron beam curable adhesive, and the like. An adhesive for an electron beam-curable polarizing film exhibits appropriate adhesion to the above various transparent protective films. Further, in the adhesive used in the present invention, a metal compound filler may be contained.

On the surface of the transparent protective film which is not attached to the polarizer, a hard coat layer may be formed or treated for anti-reflection treatment or for anti-sticking, diffusion and anti-glare treatment.

For example, as shown in FIG. 1, when the polarizing film 2 is a one-side protective polarizing film having a transparent protective film 5 on only one side of the polarizing member 4, the above-mentioned adhesive layer 3 is preferably formed in the polarizing member 4 without being transparent. The side of the protective film 5 (i.e., the side of the polarizer 4). At this time, the polarizer 4 and the adhesive layer 3 do not have to be in contact with each other. However, from the viewpoint of exhibiting the effect of the present invention remarkably, it is preferable that the phase contact is good. With such a configuration, it is possible to suppress the transfer of moisture or the like to the polarizer, and it is possible to suppress deterioration of the polarizer of the single-sided protective polarizing film.

In addition, examples of the optical film other than the polarizing plate film include a reflecting plate and a semi-transmissive plate, a retardation plate (including 1/2 and 1/4 wavelength plates), a viewing angle compensation film, and a brightness enhancement film. An optical layer to be used is formed in a liquid crystal display device or the like. Among these, a brightness enhancement film can be suitably used as an optical film. These can be used alone as an optical film, and can be laminated on the polarizing film in actual use, and one layer or two layers or more can be used.

Further, in the optical film, an activation treatment can be performed. The activation treatment can be carried out by various methods, for example, corona treatment, low pressure UV treatment, plasma treatment, and the like.

4. Optical member The optical member of the present invention includes an optical member including the above-mentioned adhesive film and an optical member (hereinafter referred to as "first optical member"), and an adhesive layer including the adhesive layer. ℃, moisture permeability at 92% RH was 1g / (m ² · day) or less of the optical film member (hereinafter referred to as "second optical member").

The first optical member further laminates the brightness enhancing film by the adhesive layer of the optical film with the adhesive layer. The optical film with the adhesive layer in the first optical member is preferably a polarizing film with an adhesive layer. For example, the optical member 10 having the polarizing film 2, the adhesive layer 3, and the brightness enhancing film 6 shown in Fig. 2 can be mentioned. Moreover, such an optical member 10 may have another layer. For example, as shown in FIG. 3, it may pass through an adhesive layer (not shown) on the side of the brightness enhancing film 6 which does not have the adhesive layer 3. The enamel sheet 7 is further laminated. The enamel sheet 7 typically has a substrate and a crotch portion. Further, in FIGS. 2 and 3, a single-sided protective polarizing film is described as in the case of FIG. 1, but a double-sided protective polarizing film may be used. As such an optical member, a polarizing plate as a backlight side of a liquid crystal display device is preferably used.

Further, as the brightness enhancement film 6, the reflection type polarizing plate can be mentioned. The reflective polarizing plate is a linear polarizing separation type polarizing plate. Typical examples thereof include a grid-type polarizing plate, a multilayer film-layered polarizing plate of two or more materials having different refractive indices, a vapor-deposited multilayer film having a different refractive index, and birefringence of two or more materials having different refractive indices. A multilayer multilayer film laminate in which two or more resin laminates having two or more kinds of resins having a refractive index difference are used, and linearly polarized light is separated by reflection/penetration in a vertical axial direction. Polarizing plate (linear polarized light separation type reflective polarizing plate). Among these, a linear polarization separation type reflective polarizing plate can be suitably used. For such a reflective polarizing plate, for example, a trade name "D-BEF" manufactured by 3M and a trade name "NIPOCS APCF" manufactured by Nitto Denko Corporation may be used.

In addition, as for the film having a moisture permeability of 1 g/m ² ·day or less at 40 ° C and 92% RH, for example, a barrier layer for an organic EL element or the like can be used. The barrier layer for the organic EL element can be, for example, polyethylene trifluoride, polychlorotrifluoroethylene (PCTFE), polyimine, polycarbonate, polyterephthalic acid. A polymer layer such as an ethylenediester, an alicyclic polyolefin or an ethylene-vinyl alcohol copolymer, or a laminate thereof, or a ruthenium or tantalum nitride coated on the polymer layer by a film formation method such as sputtering , inorganic thin films such as alumina and diamond-like carbon. An optical member having such a low moisture permeable film can be suitably used for an organic EL device, and specifically, can be used as a sealing member of an organic EL element.

5. Image display device The image display device of the present invention is characterized by comprising one or more selected from the group consisting of a polarizing film of the adhesive layer and the optical member. The image display device may, for example, be a liquid crystal display device or an organic EL display device.

The image display device of the present invention may be any optical film or optical member including the adhesive layer of the present invention, and other configurations may be the same as those of the conventional image display device.

The image display device of the present invention has high optical reliability because it includes the optical film or optical member with the above-mentioned adhesive layer. Example

The present invention will be specifically described by the following examples, but the present invention is not limited by the examples. In addition, each of the parts and % in each example is a weight basis.

(weight average molecular weight) The weight average molecular weight (Mw) was measured by a gel permeation chromatography (GPC method), and a column of an inner diameter of 6.0 mm and a length of 150 mm of HLC-8120 (manufactured by Tosoh Corporation) was used. It is produced by in-line connection of Tesco Co., Ltd., TSKgel SuperHZM-H/HZ4000/HZ3000/HZ2000. The use of tetrahydrofuran in the solution is carried out at a concentration of 1 g/L, a flow rate of 0.6 ml/min, a temperature of 40 ° C, and a sample injection amount of 20 μl. An RI detector is used in the detector. Further, in the preparation of the molecular weight calibration curve, TSK standard polystyrene (manufactured by Tosoh Corporation) was used.

Production Example 1 (Production of Polarizing Film) In order to produce a thin polarizing film, first, a laminate of a polyvinyl alcohol (PVA) layer having a thickness of 9 μm was formed on an amorphous polyethylene terephthalate (PET) substrate. The extended laminate was produced by an airborne extension extension at an extension temperature of 130 °C. Next, a colored layered body is formed by dyeing the extended laminated body, and an optical thin film laminated body including a PVA layer of 4 μm thick is formed by extending the colored laminated body by boric acid water having an extension temperature of 65 ° C. The 4 μm thick PVA layer was integrally formed with the amorphous PET substrate so that the total stretching ratio became 5.94 times. An optical thin film laminate including a PVA layer having a thickness of 5 μm, which is a high-performance polarizing film (polarizer) having a high-performance polarizing film (polarizer) formed on an amorphous PET substrate, is formed by such two-stage stretching. The PVA molecules of the PVA layer formed by the film are highly aligned, and the iodine adsorbed by the dyeing is highly aligned in one direction with the polyiodide complex.

The surface of the polarizing film (polarizer, thickness: 5 μm) of the optical film laminate according to the above-mentioned polarizer is coated with a polyvinyl alcohol-based adhesive so that the thickness of the adhesive layer is 0.1 μm, and transparent protection is applied. The film (which was subjected to corona treatment to a (meth)acrylic resin film having a lactone ring structure having a thickness of 20 μm) was bonded, and then dried at 50 ° C for 5 minutes. Next, the amorphous PET substrate was peeled off, and a one-side protective polarizing film using a thin polarizer was produced.

Example 1 100 parts by weight of a styrene-ethylene-propylene-styrene block copolymer (SEPS, trade name: SEPTON 2063, styrene content: 13%, manufactured by Kuraray) was blended as a rubber-based polymerization. (A), hydrogenated terpene phenol (trade name: YS POLYSTAR TH130, softening point: 130 ° C, hydroxyl value: 60, manufactured by Yasuhara Chemical Co., Ltd.) 40.4 parts by weight, petroleum-based adhesion-imparting agent (trade name: Piccolastic A5) , vinyl toluene-based adhesion-imparting agent, softening point: 5 ° C, manufactured by Eastman Kodak Co., Ltd., 61.7 parts as adhesion-imparting agent (B), polybutene (trade name: HV-300, weight Average molecular weight: 3000, JX Nippon Mining & Energy Co., Ltd.) 21.3 parts of toluene solution (adhesive solution) as softener (C), adjusted so that the solid content becomes 30% by weight, and the adhesive is prepared. Composition (solution).

The obtained adhesive composition (solution) was applied to a release-treated surface of a polyester film (trade name: DIAHOIL MRF, manufactured by Mitsubishi Plastics Co., Ltd.) having a thickness of 38 μm which was subjected to a release treatment on one side by polyoxymethylene. To form a coating layer. Next, the coating layer was dried at 120 ° C for 3 minutes to form an adhesive layer, and an adhesive sheet having a thickness of 20 μm of the adhesive layer was produced. Further, in the adhesive surface of the adhesive sheet, a polyester film (trade name: DIAHOIL MRF, manufactured by Mitsubishi Resin Co., Ltd.) having a thickness of 38 μm which has been subjected to a release treatment by polyfluorene on one side is used. The release treated surface is bonded to the adhesive layer. The polyester film coated on both sides of the adhesive layer functions as a release liner (separator).

One of the release liners of the above-mentioned adhesive sheet was peeled off, and a polarizing film with an adhesive layer was obtained by laminating the adhesive layer in contact with the polarizing member on the polarizing member of the polarizing film obtained in Production Example 1. . The release liner of the adhesive layer remains as a separator. The polarizing film of the obtained adhesive layer is composed of a transparent protective film/polarizer/adhesive layer/separator.

Examples 2 to 31 and Comparative Examples 1 to 7 In the same manner as in Example 1, except that the components of the adhesive composition were prepared in the first and second embodiments, the same procedure as in Example 1 was carried out. A polarizing film of the adhesive layer.

Comparative Example 8 (Production of Acrylic Adhesive Layer) 99 parts by weight of butyl acrylate (BA) and 1 part by weight of 4-hydroxybutyl acrylate (4HBA) were used as a monomer component, and 0.2 parts by weight of azobisisobutyronitrile was used. Into a separable flask equipped with a thermometer, a stirrer, a reflux cooling tube, and a nitrogen gas introduction tube, the polymerization initiator and ethyl acetate were used as a polymerization solvent so that the solid content was 20%, and then nitrogen gas was flowed while stirring. A nitrogen substitution was made for about 1 hour. Thereafter, the flask was heated to 60 ° C and allowed to react for 7 hours to obtain an acrylic polymer having a weight average molecular weight (Mw) of 1.1 million. 0.8 parts by weight of trimethylolpropane toluene diisocyanate (trade name: Coronate L, manufactured by Japan Polyurethane Co., Ltd.) was used as an isocyanate crosslinking agent and a decane coupling agent (trade name: KBM-403, 0.1 parts by weight of the above-mentioned acrylic polymer solution (solid content: 100 parts by weight) was added to prepare an acrylic pressure-sensitive adhesive composition.

A polarizing film with an adhesive layer was obtained in the same manner as in Example 1 except that the acrylic adhesive composition was used.

The following evaluations were carried out for the adhesive composition obtained in the examples and the comparative examples and the polarizing film with the adhesive layer. The evaluation results are shown in Tables 1 and 2.

<Method for Measuring Moisture Permeability> Using the adhesive compositions obtained in the examples and the comparative examples, an adhesive sheet having a thickness of the adhesive layer of 50 μm was formed in accordance with the method described in the examples. One of the release liners of the adhesive sheet was peeled off to expose the adhesive surface, and the adhesive sheet was adhered to a cellulose triacetate film (TAC film, thickness 25 μm, manufactured by Konica Minolta Co., Ltd.). Then, another release liner was peeled off to obtain a sample for measurement. Next, using the sample for measurement, the moisture permeability (water vapor transmission rate) was measured by a moisture permeability test method (cup method, JIS Z 0208) under the following conditions. Measurement temperature: 40 ° C Relative humidity: 92% Measurement time: 24 hours Further, at the time of measurement, a constant temperature and humidity chamber was used.

<Adhesive Force> Using the adhesive sheet obtained in the examples and the comparative examples, a tape piece having a length of 100 mm and a width of 25 mm was obtained. Next, one of the release liners was peeled off from the tape piece to expose the adhesive face, and the PET film (thickness: 25 μm) was attached to the adhesive face of the tape piece to prepare a release liner (adhesive layer/adhesive layer/PET film). The single-sided adhesive tape (length: 100 mm, width: 25 mm) with a substrate laminated in the order. The release liner was peeled off from the single-sided adhesive tape of the attached substrate to obtain a sample for measurement. Then, a glass plate (trade name: soda lime glass #0050, manufactured by Matsunaga Glass Industry Co., Ltd.) was bonded to the adhesive surface (measurement surface) exposed by the measurement sample in a 23 ° C, 50% RH gas atmosphere. The 2 kg roller was subjected to 1 round trip and crimped. Then, it was left in a gas atmosphere of 23 ° C, 50% R.H. for 30 minutes. After standing, a 180° peeling test for peeling the sample for measurement from the glass plate was performed using a tensile tester (trade name: TCM-1kNB, manufactured by Minebea Co., Ltd.), and the 180° peeling adhesion to the glass plate was measured (180 degrees). Pull and peel adhesion) (N/25mm). The measurement was carried out under the conditions of a peeling angle of 180° and a tensile speed of 300 mm/min in a gas atmosphere of 23° C. and 50% R·H.

<Durability> The separator of the polarizing film with the adhesive layer obtained in the examples and the comparative examples was peeled off, and the test piece was attached to a glass plate, and visually or magnified (20 times) to observe it and put it into 85 ° C. The state of the environment after 300 hours. The evaluation was carried out by the following evaluation criteria. ◎: Even if confirmed by a magnifying glass, there is no occurrence of defects (foaming, peeling, etc.). 〇: It is not possible to confirm the defect visually, but it is determined by a magnifying glass that there is a problem that there is no problem with the use. ×: The defect was confirmed by visual observation.

[Table 1]

[Table 2]

The expressions in Tables 1 and 2 are as follows. <Rubber-based polymer (A1)> SEPTON 2063: Styrene-ethylene-propylene-styrene block copolymer (SEPS, trade name: SEPTON 2063, styrene content: 13%, manufactured by Kuraray), HYBRAR 7311: Styrene-ethylene-propylene-styrene block copolymer (SEPS, trade name: HYBRAR 7311, styrene content 12%, manufactured by Kuraray), <Rubber polymer (A2)> OPPANOL B80: Polyisobutylene (Mw: about 750,000, manufactured by BASF), <Other than the polymer> OPPANOL B50: polyisobutylene (Mw: about 340,000, manufactured by BASF), OPPANOL B30: polyisobutylene (Mw: about 200,000, Acrylic adhesive composition: Acrylic adhesive composition obtained in Comparative Example 8 <Natural adhesive adhesion agent (B1)> Clearon M125: Aromatic modified terpene resin hydride (softening point: 125 °C, manufactured by Yasuhara Chemical Co., Ltd., Clearon P150: terpene hydride (softening point: 152 ° C, manufactured by Yasuhara Chemical Co., Ltd.), YS POLYSTAR TH130: hydrogenated terpene phenol (softening point: 130 ° C, hydroxyl value) : 60, manufactured by Yasuhara Chemical Co., Ltd., YS POLYSTAR UH115: fully hydrogenated terpene phenol (softening point: 115, hydroxyl value: 25, manufactured by Yasuhara Chemical Co., Ltd., fully hydrogenated terpene phenol (A): fully hydrogenated terpene phenol having a softening point of 135 ° C, a hydroxyl value of 160, and fully hydrogenated terpene phenol (B): Complete hydrogenated terpene phenol having a softening point of 135 ° C and a hydroxyl value of 60, fully hydrogenated terpene phenol (C): fully hydrogenated terpene phenol having a softening point of 160 ° C and a hydroxyl value of 60, and a petroleum resin-based adhesion-imparting agent (B2)> Piccolastic A5: Vinyl toluene adhesion-imparting agent (softening point: 5 ° C, manufactured by Eastman Kodak Co., Ltd.), T-REZ HA125: hydrogenated dicyclopentadiene-based adhesion-imparting agent (softening point: 125 ° C , Tonen General Sekiyu Co., Ltd., FMR-0150: Styrene/Aromatic Adhesive Additive (softening point: 145 ° C, manufactured by Mitsui Chemicals Co., Ltd.), Arkon P115: alicyclic saturated hydrocarbon resin (softening) Point: about 115 ° C, Arakawa Chemical Industry Co., Ltd., Arkon P125: alicyclic saturated hydrocarbon resin (softening point: about 125 ° C, manufactured by Arakawa Chemical Industry Co., Ltd.), Arkon P140: alicyclic saturated hydrocarbon resin (softening point: about 140 ° C, manufactured by Arakawa Chemical Industry Co., Ltd.), <softener (C) > OPPANOL B10: polyisobutylene (weight average) : About 36,000, BASF Corp.), HV-300: polybutylene (weight average molecular weight: 3000, JX Nippon Mining & Energy (shares) system).

1‧‧‧Polarized film with adhesive layer
2‧‧‧ polarizing film
3‧‧‧Adhesive layer
4‧‧‧ polarizer
5‧‧‧Transparent protective film
6‧‧‧ Brightening film
7‧‧‧稜鏡 Sheet
10‧‧‧Optical components

Fig. 1 is a cross-sectional view schematically showing a polarizing film with an adhesive layer according to an embodiment of the present invention. Fig. 2 is a cross-sectional view schematically showing an embodiment of an optical member of the present invention. Fig. 3 is a cross-sectional view schematically showing an embodiment of an optical member of the present invention.

1‧‧‧Polarized film with adhesive layer

2‧‧‧ polarizing film

3‧‧‧Adhesive layer

4‧‧‧ polarizer

5‧‧‧Transparent protective film

Claims (18)

An adhesive composition comprising a rubber-based polymer (A) and an adhesion-imparting agent (B), the adhesive composition characterized by: the rubber-based polymer (A) comprising a thermoplastic elastomer selected from styrene-based At least one rubber-based polymer of the group consisting of the body (A1) and the isobutylene polymer (A2), and the weight average molecular weight of the isobutylene polymer (A2) is 500,000 or more; the rubber-based polymer ( When the styrene-based thermoplastic elastomer (A1) is contained, the adhesion-imparting agent (B) is selected from the group consisting of a natural substance-based adhesion-imparting agent (B1), a petroleum-based adhesion-imparting agent (B2), and the like. At least one type of adhesion-imparting agent in the group of hydrides; when the rubber-based polymer (A) contains the isobutylene polymer (A2), the adhesion-imparting agent (B) is selected from the group consisting of natural substances At least one of the adhesion-imparting agents in the group consisting of the agent (B1) and the hydrides. The adhesive composition of claim 1, wherein the adhesion-imparting agent (B) is a natural-system adhesion-imparting agent (B1). The adhesive composition according to claim 1 or 2, wherein the natural substance adhesion-imparting agent (B1) is selected from the group consisting of an adhesion-imparting agent containing a terpene skeleton, an adhesion-imparting agent containing a rosin skeleton, and the like. At least one of the groups formed. The adhesive composition according to any one of claims 1 to 3, wherein the adhesive layer having a thickness of 50 μm formed of the above-mentioned adhesive composition has a moisture permeability at 40 ° C and 92% RH of 100 g / (m ² · day) )the following. The adhesive composition according to any one of claims 1 to 4, wherein the aforementioned adhesion-imparting agent (B) is a hydride. The adhesive composition according to any one of claims 1 to 5, wherein the adhesion-imparting agent (B) has a softening point of 100 ° C or more. The adhesive composition according to any one of claims 1 to 6, wherein the aforementioned natural substance adhesion-imparting agent (B1) contains a cyclohexanol skeleton. The adhesive composition according to any one of claims 1 to 7, wherein the content of the adhesion-imparting agent (B) is 1 part by weight or more based on 100 parts by weight of the rubber-based polymer (A). The adhesive composition according to any one of claims 1 to 8, which further comprises at least one selected from the group consisting of a polyisobutylene compound (C1) and a polyisoprene compound (C2). In the softening agent (C), the weight average molecular weight of the polyisobutylene compound (C1) is 50,000 or less, and the weight average molecular weight of the polyisoprene compound (C2) is 50,000 or less. The adhesive composition of claim 9, wherein the content of the softener (C) is 1 part by weight or more based on 100 parts by weight of the rubber-based polymer (A). An adhesive layer formed by the adhesive composition according to any one of claims 1 to 10. An optical film with an adhesive layer characterized by having an optical film and an adhesive layer as claimed in claim 11 disposed on the optical film. The optical film of the adhesive layer of claim 12, wherein the optical film is a polarizing film having a transparent protective film on at least one side of the polarizing member. The optical film of the adhesive layer of claim 13, wherein the polarizing film is a single-sided protective polarizing film having a transparent protective film on one side of the polarizing member, and the adhesive layer is laminated on the polarizing member without a transparent protective film. On the side. An optical film of the adhesive layer of claim 12, wherein the optical film is a brightness enhancing film. An optical member comprising an optical film and a brightness enhancing film comprising an adhesive layer as claimed in claim 13 or 14. An optical member, wherein the adhesive layer comprising the request and the entry of moisture through 11 at 40 ℃, 92% RH of the 1g / (m ² · day) or less of the film. An image display device comprising at least one selected from the group consisting of an optical film of the adhesive layer as claimed in claims 12 to 15 and an optical member according to claims 16 to 17.