TW201713739A - Adhesive composition and method for producing same, and adhesive product - Google Patents

Abstract

This adhesive composition is characterized by containing a vinyl polymer(A) having a Tg of 40-200 DEG C and a number average molecular weight of 500-10,000, and an acrylic adhesive polymer (B), wherein the acrylic adhesive polymer (B) contains a structural unit derived from (meth)acrylic acid alkoxyalkyl ester by 85 mass% or more with respect to all structural units, the ratio of the vinyl polymer(A) with respect to 100 parts by mass of the acrylic adhesive polymer (B) is 0.5-30 parts by mass, and, when an adhesive layer is obtained by coating the adhesive composition on a separator and drying the adhesive composition, the Tg calculated from a chemical composition which is of the outer layer portion of the adhesive layer and which is obtained through X-ray photoelectron spectroscopic analysis of the adhesive layer is at least 30 DEG C higher than the Tg of the adhesive composition.

Description

Adhesive composition, method of manufacturing the same, and adhesive article

The present invention relates to an adhesive composition and a method of producing the same. More specifically, the adhesive composition excellent in transparency and adhesion to various adherends, a method for producing the same, and an adhesive article using the same.

The adhesive (also referred to as a pressure-sensitive adhesive) is processed into a tape, a label, or the like, for example, and is used in a wide range of applications. In addition, the object to be adhered is also applicable to various materials such as plastic, paper, metal, glass and ceramics.

On the other hand, with the advancement of electronic technology in recent years, various flat panel displays (FPDs) such as liquid crystal displays (LCDs) or plasma display panels (PDPs) have become display devices in various fields. use.

Such display devices generally have a laminated structure in which a transparent plastic material such as glass or polycarbonate is adhered via an adhesive. In such a use, the adhesive must of course have transparency which does not impair the visibility of the transparent plastic substrate or the optical film, and is required to be subjected to a severe durability test under high temperature or high temperature and high humidity conditions, and does not occur. Peeling or arching of the substrate interface. special When a plastic plate such as a polycarbonate resin plate or an acrylic plate is used on the substrate, exhaust gas due to absorbed moisture or residual volatile substances occurs. Therefore, the optical film formed by bonding the plastic substrate and the base film having a barrier property such as a polyethylene terephthalate (PET) film is adhered by an adhesive to obtain a laminate, and then exposed to a high temperature. When it is under high humidity, due to bubbles (foaming) generated from a plastic substrate or the like, arching or peeling occurs in the subsequent interface with the adhesive layer, which is not only an appearance problem but also significantly impairs visibility. .

As described above, there has been disclosed a method in which an adhesive layer having a high adhesive modulus and a high dimensional stability is bonded to a substrate by using an adhesive having a high storage modulus, thereby suppressing the swelling or peeling. However, when such an adhesive is applied to a surface having a stepped shape or a concave-convex shape, the uneven shape of the adhesive surface or the like cannot be sufficiently followed, and a void may be formed on the end surface of the uneven portion or the like. Therefore, various adhesive compositions have been proposed which have a highly flexible adhesive polymer as a main component.

Patent Document 1 describes an adhesive composition containing a high molecular weight (meth) acrylate polymer and a low molecular weight (meth) acrylate polymer, and which can form a pseudo crosslinked structure. Patent Document 2 describes an adhesive composition for a polarizing plate comprising a specific (meth)acrylic copolymer having a different molecular weight, a toluene diisocyanate isocyanate compound, and a decane coupling agent.

Further, Patent Document 3 discloses an adhesive composition composed of a specific (meth)acrylic copolymer and a specific acrylic copolymer oligomer and a crosslinking agent having a SP value difference of 1.0 or less. Durable The essence of good balance of properties such as sex, adhesion, step followability, corrosivity, and transparency. Patent Document 4 discloses a specific low content of an adhesive polymer containing an alkoxyalkyl (meth)acrylate as a main component and an amine group-containing monomer or a mercaptoamine-containing monomer in a constituent monomer. The molecular weight polymer and the adhesive composition of the crosslinking agent exhibit the effect of suppressing foaming in a high-temperature, high-humidity environment and whitening due to moisture intrusion into the adhesive layer.

Further, Patent Document 5 discloses an adhesive composition containing a specific low molecular weight vinyl polymer and an acrylic adhesive polymer and having excellent adhesion strength to polycarbonate and polymethyl methacrylate sheets.

[Previous Technical Literature] [Patent Document]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2012-41453

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2011-232470

[Patent Document 3] Japanese Laid-Open Patent Publication No. 2011-162593

[Patent Document 4] Japanese Patent Laid-Open Publication No. 2002-327160

[Patent Document 5] Japanese Patent Laid-Open Publication No. 2014-88549

The adhesive composition described in Patent Documents 1 to 3 is effective for preventing arching or peeling due to a difference in heat shrinkage with a substrate, but is generated by exhausting from a plastic substrate under high temperature and high humidity conditions. caused The arching or peeling cannot be adequately suppressed. The adhesive composition described in Patent Documents 4 and 5 improves the performance of foaming due to exhaust gas when the plastic substrate is used. However, it is desirable to further improve durability and the like by the combination of an adhesive polymer and a low molecular weight polymer.

In addition, in recent years, product development systems having excellent design properties have progressed, and terminals having various shapes have been distributed on the market. In such a case, it is required for the adhesive to rise to the adhesion of the curved surface portion, and the specific effects of the curved surface are not shown in the above-mentioned respective patent documents.

In the present specification, it is provided that it exhibits sufficient transparency and good adhesion to various adherends, and has durability capable of suppressing foaming derived from exhaust gas in use under high temperature and high humidity conditions, and excellent adhesion of curved surface adhesion. A composition of a composition, a method for producing the same, and an adhesive article formed using the adhesive composition.

The inventors of the present invention have focused their efforts on the above problems, and have focused on a specific adhesive composition containing an acrylic adhesive polymer and a low molecular weight vinyl polymer. That is, when the adhesive layer is formed by the adhesive composition containing the specified acrylic adhesive polymer and the vinyl polymer of the specified molecular weight range, the low molecular weight vinyl polymer can be segregated to the adhesive. The surface layer of the agent layer. Further, the adhesive composition has been found to have an effect of suppressing the above-described foaming from the exhaust gas under high temperature and high humidity, and exhibits excellent curved surface adhesion. The present invention provides the following means.

The means provided in this specification are as follows

[1] An adhesive composition comprising a vinyl polymer (A) having a glass transition temperature (Tg) of 40 ° C or more and 200 ° C or less and a number average molecular weight of 500 to 10,000 and an acrylic adhesive polymer (B) The adhesive composition of the acrylic-based adhesive polymer (B) is a constituent unit derived from a (meth)acrylic acid alkoxyalkyl ester in an amount of 85% by mass or more based on all the constituent units thereof. The ratio of the vinyl polymer (A) is from 0.5 part by mass to 30 parts by mass or less based on 100 parts by mass of the acrylic pressure-sensitive adhesive (B), and the adhesive composition is applied onto a separator. When the adhesive layer is obtained by drying, the Tg of the adhesive layer calculated from the composition of the surface portion obtained by X-ray photoelectron spectroscopy is higher than the Tg of the entire adhesive layer by 30 ° C or more.

[2] The adhesive composition according to the above [1], wherein the vinyl polymer (A) has at least 1 selected from the group consisting of an aliphatic cyclic vinyl compound and an aromatic vinyl compound. The unit of construction from the monomer.

[3] The adhesive composition according to the above [1] or [2], wherein a film thickness of 50 μm formed of the above-mentioned adhesive composition is provided on a 100 μm thick polyethylene terephthalate film substrate. The adhesive sheet of the adhesive layer has a bonding strength of 15 N/25 mm or more for a polycarbonate plate of 85 °C.

[4] The adhesive composition according to [1] or [2] above, wherein The adhesive sheet of the adhesive layer having a film thickness of 50 μm formed of the above-mentioned adhesive composition on a 100 μm thick polyethylene terephthalate film substrate has a bonding strength of 5.0 N for a polypropylene plate of 85 ° C. /25μm or more.

[5] A method for producing an adhesive composition comprising 100 parts by mass of an acrylic adhesive polymer (B) containing 85 mass% or more of a constituent unit derived from an alkoxyalkyl (meth)acrylate. When 0.5 parts by mass or more and 30 parts by mass or less of the glass transition temperature (Tg) of 40 ° C or more and 200 ° C or less and a number average molecular weight of 500 to 10,000 are blended, the adhesive composition is coated. On the separator, the Tg calculated from the composition of the surface portion obtained by X-ray photoelectron spectroscopy of the obtained adhesive layer is higher than the Tg of the entire adhesive layer by 30 ° C or more. The vinyl polymer (A) and the acrylic adhesive polymer (B) described above are blended.

[6] An adhesive sheet or an adhesive tape which is formed by providing an adhesive layer formed of the adhesive composition according to any one of the above [1] to [4] on one surface or both surfaces of the substrate. .

[7] An adhesive article which is laminated on a single side or both sides of an adhesive layer formed of the adhesive composition according to any one of the above [1] to [4], and/or transparent Made of plastic sheet.

[8] An adhesive article comprising an adhesive article having an adhesive layer, wherein the adhesive layer contains a vinyl polymer having a glass transition temperature (Tg) of 40 ° C or more and 200 ° C or less and a number average molecular weight of 500 to 10,000. (A) and the acrylic adhesive polymer (B), the acrylic adhesive polymer (B) contains 85 mass% or more of alkoxyalkyl (meth)acrylate based on all the constituent units thereof. The ratio of the vinyl polymer (A) is from 0.5 part by mass to 30 parts by mass, based on 100 parts by mass of the acrylic pressure-sensitive adhesive (B), in the thickness direction of the pressure-sensitive adhesive layer. The vinyl polymer (A) is contained in a higher concentration in at least one of the opposite surface layers.

[9] The adhesive article according to the above [8], wherein the Tg of the adhesive layer calculated from the composition of the surface portion obtained by X-ray photoelectron spectroscopy is 30 ° C higher than the Tg of the entire adhesive layer. the above.

By the adhesive composition (hereinafter also referred to as the present adhesive composition) disclosed in the present specification, it is possible to obtain an adhesive article which is sufficiently transparent and exhibits good adhesion to various adherends. Moreover, the above-mentioned adhesive product can suppress the foaming derived from the exhaust gas even when it is used under high temperature and high humidity conditions, so that the problem of deterioration of visibility due to swelling or peeling of the adhesive product, and the like, and the curved surface are eliminated. It is also excellent in the following.

[Formation of the Invention]

This specification relates to the adhesive composition, which contains A specific adhesive composition of a specified vinyl polymer and an acrylic adhesive polymer, characterized in that the adhesive layer formed from the composition is a surface portion thereof obtained by X-ray photoelectron spectroscopy. The calculated Tg of the composition is higher than the Tg of the entire adhesive layer by 30 ° C or more, and the method for producing the same, and the adhesive article formed using the adhesive composition.

The present adhesive composition is obtained by combining a vinyl polymer (A) having a certain glass transition temperature and a number average molecular weight at a certain ratio with an alkoxyalkyl (meth)acrylate having 85% by mass or more. The acrylic adhesive polymer (B) is formed in a unit, and when the adhesive layer is formed, the vinyl polymer (A) can be segregated to the surface layer of the adhesive layer. The segregation behavior of the vinyl polymer (A) is based on the fact that the specific vinyl polymer (A) described above is not completely compatible with the acrylic adhesive polymer (B) but is not completely phase separated. Further, the segregation behavior is based on the fact that the vinyl polymer (A) is at least lower than the acrylic adhesive polymer (B).

The present adhesive composition is as described above, and a vinyl polymer (A) which is incompletely compatible with the acrylic adhesive polymer (B) is used. At this time, the degree of segregation can be adjusted by appropriately adjusting the amount of the vinyl polymer (A) used in the adhesive composition. When the amount of the vinyl polymer (A) used is too small, the segregation of the surface layer of the adhesive layer is insufficient, and a sufficient effect may not be obtained. On the other hand, when the amount of the vinyl polymer (A) used is too large, it is separated from the acrylic adhesive polymer (B), and as a result, the transparency or the adhesion property of the adhesive layer tends to decrease. In addition, by suitably adjusting the glass of the vinyl polymer (A) The transfer temperature adjusts the glass transition temperature of the surface portion of the adhesive layer.

Further, the segregation of the vinyl polymer (A) occurs at the time of formation of the adhesive layer, and the vinyl polymer (A) segregates to the interface side where the surface energy is low. Therefore, for example, in the sheet-like or film-like adhesive layer formed by the present adhesive composition, when the two surface layers opposed in the thickness direction are in contact with a substance having a low surface energy such as a gas or a solid. An adhesive layer is obtained which contains the vinyl polymer (A) at a higher concentration in the low surface energy interface side in contact with the substance, but on the other hand, on the central side in the thickness direction of the adhesive layer The lower concentration contains the vinyl polymer (A). That is, an adhesive layer having a tilted composition having a vinyl polymer (A) at a higher concentration in the surface layer side of the adhesive can be obtained. From the viewpoint of the acrylic adhesive polymer (B), an adhesive layer having an inclined composition having an acrylic adhesive polymer (B) at a lower concentration on the surface side of the adhesive can be obtained.

Further, for example, in the sheet-like or film-like adhesive layer formed by the adhesive composition, when only one of the two surface layers opposed in the thickness direction becomes the low surface energy interface side, An adhesive layer having a vinyl polymer (A) is contained at a higher concentration in the interface side.

The adhesive composition is a result of segregation of the vinyl polymer (A) in the adhesive layer, and the Tg comparable to the adhesive calculated from the composition of the surface portion obtained by X-ray photoelectron spectroscopy. The Tg of the entire layer is higher by 30 ° C or more. Thereby, the adhesive properties of the adhesive layer can be controlled to obtain good adhesion strength. That is, in the vicinity of the interface formed by the surface layer of the adhesive, since it has a relatively high Tg, Presenting good connectivity that was not available in the past. For example, even if there is exhaust gas from the attached body at a high temperature, the adhesion or peeling of the adhesive layer can be suppressed, and good durability can be exhibited. Further, the entire adhesive layer can have good followability to the attached body.

Hereinafter, the disclosure of the present specification will be described in detail. In addition, in the present specification, the term "(meth)acrylic acid" means acrylic acid and/or methacrylic acid, and the so-called "(meth) acrylate" means acrylate and/or methyl group. Acrylate. Moreover, the "(meth)acryloyl group" means an acryloyl group and/or a methacryl fluorenyl group.

The adhesive composition contains a vinyl polymer (A) and an acrylic adhesive polymer (B). The details of the vinyl polymer (A), the acrylic adhesive polymer (B), and the adhesive composition containing the same will be described below in order.

[vinyl polymer (A)]

The vinyl polymer (A) of the present invention is a polymer having a glass transition temperature (Tg) of 40 ° C or more and 200 ° C or less. The lower limit of Tg can be set to 50 ° C or more and 60 ° C or more. Further, the upper limit may be 180 ° C or lower, 150 ° C or lower, or 120 ° C or lower. Furthermore, it can also be set to 100 ° C or less. Further, the range of Tg may be 60 ° C or more and 180 ° C or less, and 60 ° C or more and 150 ° C or less. Further, in the present invention, a value measured by a differential scanning calorimetry (DSC) at a temperature elevation rate of 10 ° C /min is used as the Tg. If the Tg is less than 40 ° C, the adhesion strength to various attached bodies is insufficient. There is a case of poor durability. Further, it is generally not more than 200 ° C due to restrictions on raw material monomers and the like.

As the monomer constituting the vinyl polymer (A), various ethylenically unsaturated compounds having radical polymerizability can be used, and examples thereof include a (meth) acrylate compound, an aliphatic cyclic vinyl compound, and an aromatic compound. Vinyl compound, unsaturated carboxylic acid, unsaturated acid anhydride, hydroxyl group-containing vinyl compound, amine group-containing vinyl compound, mercapto group-containing vinyl compound, alkoxy group-containing vinyl compound, cyano group-containing A vinyl compound, a nitrile group-containing vinyl compound, a maleic imine compound, or the like. These compounds may be used singly or in combination of two or more.

Among these, the aliphatic cyclic vinyl compound and the aromatic vinyl compound tend to have good adhesion properties in the adhesive layer. By using such a vinyl compound, it is easy to obtain a vinyl polymer (A) having a relatively low polarity to the adhesive polymer (B), and the vinyl polymer (A) can be easily formed when the adhesive layer is formed. Segregation to the surface. Therefore, the vinyl polymer (A) may have a structural unit derived from at least one monomer selected from the group consisting of an aliphatic cyclic vinyl compound and an aromatic vinyl compound. The specific amount of at least one monomer selected from the group consisting of an aliphatic cyclic vinyl compound and an aromatic vinyl compound can be appropriately set, and for example, the lower limit can be 3% by mass or more. It is set to 5 mass% or more and 10 mass% or more. Further, the upper limit thereof may be, for example, 80% by mass or less, 60% by mass or less, or 50% by mass or less. In addition, for example, the amount of use may be 3% by mass or more and 80% by mass or less, 5% by mass or more and 60% by mass or less, and may be 10 mass%. % or more and 50% by mass or less.

Examples of the (meth) acrylate compound include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, and (methyl). N-butyl acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, amyl (meth)acrylate, n-hexyl (meth)acrylate, n-octyl (meth)acrylate, a (meth) acrylate compound containing a linear or branched alkyl group such as 2-ethylhexyl (meth)acrylate, n-dodecyl (meth)acrylate or n-octadecyl (meth)acrylate . These compounds may be used singly or in combination of two or more. For example, methyl (meth)acrylate can also be used.

Examples of the aliphatic cyclic vinyl compound include cyclohexyl (meth)acrylate, methylcyclohexyl (meth)acrylate, and t-butylcyclohexyl (meth)acrylate, and (methyl). Cyclodecyl acrylate, isobornyl (meth) acrylate, adamantyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentanyl (meth) acrylate, and the like. These compounds may be used singly or in combination of two or more.

Among these, in the case where a relatively high Tg can be set, the vinyl polymer (A) tends to segregate to the surface layer when the adhesive layer is formed, and has a tendency to obtain good adhesion properties, and may be ( Isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, cyclohexyl (meth)acrylate, and adamantyl (meth)acrylate. Among them, isobornyl (meth)acrylate may also be used.

Examples of the aromatic vinyl compound include styrene, α-methylstyrene, o-methylstyrene, p-methylstyrene, vinyltoluene, β-methylstyrene, and ethylstyrene. , p-t-butyl styrene, vinyl xylene, vinyl naphthalene, and the like. These compounds may be used singly or in combination of two or more. For example, styrene, etc.

Examples of the unsaturated carboxylic acid include a single (meth)acrylic acid, ethacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, citraconic acid, cinnamic acid, and an unsaturated dicarboxylic acid. An alkyl ester (monoalkyl ester such as maleic acid, acid rich, itaconic acid, citraconic acid, maleic anhydride, itaconic anhydride, citraconic anhydride, etc.). These compounds may be used singly or in combination of two or more.

Examples of the unsaturated acid anhydride include maleic anhydride, itaconic anhydride, and citraconic anhydride. These compounds may be used singly or in combination of two or more.

Examples of the hydroxyl group-containing vinyl compound include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and (meth)acrylic acid 2. a mono(meth)acrylate of a polyalkylene glycol such as hydroxybutyl ester, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, polyethylene glycol or polypropylene glycol, or P-hydroxystyrene, m-hydroxystyrene, o-hydroxystyrene, p-isopropenylphenol, m-isopropenylphenol, o-isopropenylphenol, and the like. These compounds may be used singly or in combination of two or more.

Examples of the amino group-containing vinyl compound include dimethylaminomethyl (meth)acrylate and diethylamine (meth)acrylate. Methyl ester, 2-dimethylaminoethyl (meth)acrylate, 2-diethylaminoethyl (meth)acrylate, 2-(di-propylamino)(meth)acrylate Ester, 2-dimethylaminopropyl (meth)acrylate, 2-diethylaminopropyl (meth)acrylate, 2-(di-n-propylamino)propyl (meth)acrylate, ( 3-dimethylaminopropyl methacrylate, 3-diethylaminopropyl (meth)acrylate, 3-(di-n-propylamino)propyl (meth)acrylate, and the like. These compounds may be used singly or in combination of two or more.

Examples of the mercaptoamine-containing vinyl compound include (meth)acrylamide, N,N-dimethyl(meth)acrylamide, and N,N-dimethylaminopropyl (methyl). Acrylamide, N-methylol (meth) acrylamide, and the like. These compounds may be used singly or in combination of two or more.

Examples of the alkoxy group-containing vinyl compound include methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, n-propoxyethyl (meth)acrylate, and (methyl). ) n-butoxyethyl acrylate, methoxypropyl (meth)acrylate, ethoxypropyl (meth)acrylate, n-propoxypropyl (meth)acrylate, n-butyl (meth)acrylate Oxypropyl propyl ester and the like. These compounds may be used singly or in combination of two or more.

Examples of the cyano group-containing vinyl compound include cyanomethyl (meth)acrylate, 1-cyanoethyl (meth)acrylate, 2-cyanoethyl (meth)acrylate, and (methyl). 1-cyanopropyl acrylate, 2-cyanopropyl (meth)acrylate, 3-cyanopropyl (meth)acrylate Ester, 4-cyanobutyl (meth)acrylate, 6-cyanohexyl (meth)acrylate, 2-ethyl-6-cyanohexyl (meth)acrylate, (meth)acrylic acid 8- Cyanooctyl ester and the like. These compounds may be used singly or in combination of two or more.

Examples of the nitrile group-containing vinyl compound include (meth)acrylonitrile, ethacrylonitrile, α-ethylacrylonitrile, α-isopropylacrylonitrile, α-chloroacrylonitrile, and α-fluoroacrylonitrile. Wait. These compounds may be used singly or in combination of two or more.

Examples of the maleimide-based compound include sulfimine, N-methylmaleimide, N-isopropylmaleimide, N-butylmaleimide, and N- Twelve kimaylide imine, N-cyclohexylmaleimide, N-phenylmaleimide, N-(2-methylphenyl)maleimide, N-(4- Methylphenyl)maleimide, N-(2,6-dimethylphenylmaleimide, N-(2,6-diethylphenyl)maleimide, N- Benzyl maleimide, N-naphthyl maleimide, etc. These compounds may be used singly or in combination of two or more.

In addition to the above compounds, a dialkyl ester of an unsaturated dicarboxylic acid, a vinyl ester compound, a vinyl ether compound or the like can be used.

The dialkyl ester of the unsaturated dicarboxylic acid may, for example, be a dialkyl ester such as maleic acid, fumaric acid, itaconic acid, citraconic acid, maleic anhydride, itaconic anhydride or citraconic anhydride.

Examples of the vinyl ester compound include a methylene aliphatic monocarboxylic acid ester, vinyl acetate, vinyl propionate, trimethyl vinyl acetate, vinyl butyrate, vinyl benzoate, vinyl formate, and cinnamon. Acid vinyl ester and the like.

Examples of the vinyl ether compound include vinyl methyl ether, vinyl ethyl ether, vinyl n-butyl ether, vinyl isobutyl ether, vinyl phenyl ether, and vinyl cyclohexyl ether.

The number average molecular weight (Mn) of the vinyl polymer (A) may be 500 or more and 10,000 or less. The lower limit may be set to 1,000 or more and 1,500 or more. Further, the upper limit may be 7,000 or less, 5,000 or less, or 4,000 or less. Further, the range may be 500 or more and 7,000 or less, and 1,000 or more and 5,000. When Mn exceeds 10,000, the compatibility with the acrylic adhesive polymer (B) is deteriorated. On the other hand, in order to produce a polymer having a Mn of less than 500, there is a problem that a polymerization initiator or a chain transfer agent is used in a large amount, or productivity is lowered.

In addition, the ratio (Mw/Mn) of the weight average molecular weight (Mw) to the above (Mn) may be 3.0 or less, 2.2 or less, or 1.8 or less from the viewpoint of easily obtaining good adhesion strength.

Here, the number average molecular weight (Mn) and the weight average molecular weight (Mw) are standard polystyrene equivalent values obtained by gel permeation chromatography (GPC).

The vinyl polymer (A) of the present invention is not particularly limited in its production method, and can be easily obtained, for example, by polymerizing the above monomers by a known radical polymerization method such as a solution polymerization method.

In the solution polymerization method, an organic solvent and an alkenyl monomer raw material are added to a reactor, and a thermal polymerization initiator such as an organic peroxide or an azo compound is added and heated to 50 to 300 ° C. Aggregation, can get the purpose Vinyl polymer. The vinyl polymer may be used as a solution dissolved in an organic solvent, or may be used by distilling off the solvent by heating under reduced pressure or the like.

The method for adding the raw materials containing the monomers may be the initial batch addition of the batch in which all the raw materials are added in batches, or may be a semi-continuous addition in which at least one raw material is continuously supplied to the reactor, or In order to continuously supply all the raw materials, a continuous polymerization method of producing a resin is continuously extracted from the reactor.

As the organic solvent used in the solution polymerization method, an organic hydrocarbon compound is suitable, and tetrahydrofuran and two are exemplified. a cyclic ether such as an alkane; an aromatic hydrocarbon compound such as benzene, toluene or xylene; an ester such as ethyl acetate or butyl acetate; a ketone such as acetone, methyl ethyl ketone or cyclohexanone; One or two or more kinds of these may be used as the alcohol such as methyl orthoformate, methyl orthoacetate, methanol, ethanol or isopropyl alcohol. Among these polymerization solvents, in order to dissolve the ethylene-based polymer well, it is easy to purify, and ethyl acetate, butyl acetate, acetone, or methyl ethyl ketone having a relatively low boiling point may be used.

The initiator used in the present invention may be an azo compound, an organic peroxide, an inorganic peroxide or the like, but is not particularly limited. A redox type polymerization initiator prepared from a well-known oxidizing agent and a reducing agent can be used. Further, a well-known chain transfer agent can also be used in combination.

Examples of the azo-based compound include 2,2'-azobis(isobutyronitrile), 1,1-azobis(cyclohexane-1-carbonitrile), azocumene, and 2, 2'-azobis(2-methylbutyronitrile), 2,2'-azobisdimethylpenta Nitrile, 4,4'-azobis(4-cyanovaleric acid), 2-(t-butylazo)-2-cyanopropane, 2,2'-azobis (2,4,4 - Trimethylpentane), 2-2'-azobis(2-methylpropane), dimethyl 2,2'-azobis(2-methylpropionate), and the like.

Examples of the organic peroxide include cyclohexanone peroxide, 3,3,5-trimethylcyclohexanone peroxide, methylcyclohexanone peroxide, and 1,1-double (third Butyl peroxy)-3,3,5-trimethylcyclohexane, 1,1-bis(t-butylperoxy)cyclohexane, n-butyl-4,4-bis(t-butyl Peroxy) valerate, cumene hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, 1,3-bis(t-butylperoxy)-m -isopropyl)benzene, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, diisopropylbenzene peroxide, tert-butyl cumyl peroxide , mercapto peroxide, lauryl peroxide, benzhydryl peroxide, 2,4-dichlorobenzhydryl peroxide, bis(t-butylcyclohexyl)peroxy Carbonate, tert-butyl peroxybenzoate, 2,5-dimethyl-2,5-bis(benzimidyl peroxy)hexane, and the like.

Examples of the inorganic peroxide include potassium persulfate, sodium persulfate, and ammonium persulfate.

Further, as the redox type polymerization initiator, sodium sulfite, sodium thiosulfate, sodium formaldehyde sulfonate, ascorbic acid, ferrous sulfate or the like may be used as a reducing agent, and potassium peroxydisulfate, hydrogen peroxide, and third may be used. Butyl hydroperoxide or the like is used as an oxidant.

Further, the vinyl polymer (A) of the present invention can also be continuously used in a temperature range of 180 to 350 ° C by using a stirred tank type reactor. Aggregated. In this polymerization method, a relatively low molecular weight vinyl polymer can be obtained without substantially using a polymerization initiator or a chain transfer agent, and a polymer having high purity can be obtained, which is advantageous in terms of coloring or odor which will be described later. Preferably. When the polymerization temperature is less than 180 ° C, a polymerization initiator or a large amount of a chain transfer agent is required in the polymerization reaction, and the obtained copolymer is easily colored, and an unpleasant odor is generated. On the other hand, when the polymerization temperature exceeds 350 ° C, the decomposition reaction tends to occur in the polymerization reaction, and the obtained copolymer is colored. Therefore, the transparency of the adhesive layer obtained from the adhesive composition containing the above is lowered. Further, a vinyl polymer having a small molecular weight distribution range is obtained by such a polymerization method. Further, the polymerization initiator may be used arbitrarily, and may be used in an amount of about 1% by mass or less based on the total monomers.

[Acrylic Adhesive Polymer (B)]

The acrylic adhesive polymer (B) is a polymer containing a (meth) acrylate compound as a main constituent unit. Further, it may be an adhesive polymer having a glass transition temperature (Tg) in the range of -80 ° C to -10 ° C or less. Further, it may be in the range of -70 ° C or more and -20 ° C or less. When the Tg is -80 ° C or more, it has sufficient cohesive force as an adhesive and exhibits good curved surface adhesion. On the other hand, when Tg is -10 ° C or less, good performance is also exhibited at the point of adhesion to the uneven portion and adhesion at low temperature.

In addition, the acrylic adhesive polymer (B) may have a weight average molecular weight (Mw) of 100,000 or more and 250,000 or more from the viewpoint of exhibiting sufficient cohesive force and good adhesion. More than 400,000.

On the other hand, if the weight average molecular weight is too high, handling in production may become difficult. Therefore, the upper limit may be 2,000,000 or less, 1,500,000 or less, or 1,000,000 or less.

In the present specification, the acrylic pressure-sensitive adhesive (B) is a constituent unit derived from an alkoxyalkyl (meth)acrylate in an amount of 85% by mass or more based on all of its constituent units. Thereby, an acrylic adhesive polymer which is excellent in softness and adhesion is obtained, and when an adhesive layer is formed from the adhesive composition containing the above vinyl polymer (A), an acrylic adhesive polymer (B) is obtained. The polarity of the vinyl polymer (A) can be relatively lowered, and as a result, the vinyl polymer (A) can be segregated to the surface layer to exhibit good adhesion properties. The amount of the (meth)acrylic alkoxyalkoxyalkyl ester used may be 90% by mass or more, 92% by mass or more, and 95% by mass or more. In addition, the upper limit of the amount of the (meth)acrylic acid alkoxyalkyl ester used is 100% by mass or less, and may be 99.5% by mass or less, or may be 99.0% by mass or less.

Examples of the alkoxyalkyl (meth)acrylate include methoxymethyl (meth)acrylate, ethoxylate (meth)acrylate, and butoxymethyl (meth)acrylate. Methyl) methoxyethyl acrylate, ethoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, methoxybutyl (meth) acrylate, ethoxy (meth) acrylate An alkoxyalkyl (meth)acrylate having an alkoxyalkyl group having 2 to 8 carbon atoms, such as a butyl butyl acrylate or a butoxybutyl (meth) acrylate, etc., such that the above vinyl polymer (A) ) the segregation is easy to occur, and can also be used An alkoxyalkyl (meth)acrylate having an alkoxyalkyl group having 2 to 4 carbon atoms. In addition, one type or two or more types of the above-mentioned (meth)acrylic acid alkoxyalkyl esters can be used.

The acrylic adhesive polymer (B) is a monomer which can be copolymerized with the above, in addition to the above-mentioned (meth)acrylic acid alkoxyalkyl ester, within a range not impairing the effects of the present invention. Examples of the copolymerizable monomer include alkyl (meth)acrylate, polyalkylene glycol mono(meth)acrylate, and other vinyl monomers.

Examples of the alkyl (meth)acrylate include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, and isopropyl (meth)acrylate. Base) n-butyl acrylate, isobutyl (meth)acrylate, n-hexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethyl (meth)acrylate Examples include hexyl hexyl ester, n-decyl (meth) acrylate, isodecyl (meth) acrylate, n-decyl (meth) acrylate, lauryl (meth) acrylate, and the like. Base) n-butyl acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, n-decyl (meth)acrylate, (methyl) For the isodecyl acrylate or the like, one type or two or more types of these may be used.

Examples of the polyalkylene glycol mono(meth)acrylate include polyethylene glycol mono(meth)acrylate, methoxypolyethylene glycol mono(meth)acrylate, and polypropylene glycol mono(A). Acrylate, methoxypolypropylene glycol mono(meth)acrylate, polyethylene glycol-polypropylene glycol- One type or two or more types of these may be used for the mono(meth)acrylate or the like.

Examples of the other vinyl monomer include α,β-ethylenically unsaturated carboxylic acid monomers such as (meth)acrylic acid, itaconic acid, maleic acid, and fumaric acid; styrene and α-methyl group; An aromatic vinyl compound such as styrene or vinyl toluene; cyclohexyl (meth)acrylate, methylcyclohexyl (meth)acrylate, t-butylcyclohexyl (meth)acrylate, (methyl) An aliphatic cyclic vinyl compound such as cyclopentyl acrylate or isobornyl (meth)acrylate; a monoalkyl ester of an unsaturated dicarboxylic acid such as monoethyl orthobutanate or monobutyl fumarate; 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, polyethylene glycol (meth)acrylate, polypropylene glycol (methyl) a hydroxyl group-containing monomer such as acrylate and polyethylene-polypropylene glycol mono(meth)acrylate; acrylamide, N-methylol acrylamide, N-methoxymethyl propylene amide, N-A Ethylene-based unsaturated carboxamide and N-substituted compound such as oxybutyl acrylamide; unsaturated alcohol such as allyl alcohol; (meth) acrylonitrile, vinyl acetate, (meth) propylene Glycidyl methacrylate, diacetone acrylamide and the like, may be used or two or more of these within the.

The amount of the other monomer used may be in the range of 0% by mass or more and 10% by mass or less, or may be 0.5% by mass or more and 8.0% by mass or less, and 1.0% by mass or more and 5.0% by mass or less.

The acrylic adhesive polymer (B) can also be obtained by a well-known radical polymerization method such as a solution polymerization method, a suspension polymerization method, or an emulsion polymerization method.

[adhesive composition]

The present adhesive composition contains the above vinyl polymer (A) and the above acrylic adhesive polymer (B) at a specified blend ratio. Further, when the adhesive layer is obtained from the present adhesive composition, the vinyl polymer (A) can be segregated to the surface layer, and the distribution of Tg in the adhesive layer is also segregated, thereby obtaining good adhesion strength. The segregation behavior of the vinyl polymer (A) and the difference in Tg between the surface layer of the adhesive layer and the entire adhesive layer described later can be suitably set by the vinyl polymer (A) relative to the acrylic adhesive polymer. The blending ratio of (B), the monomer composition (polarity) or molecular weight of the vinyl polymer (A), and Tg, Mw/Mn, and the like are adjusted.

The adhesive composition may contain 0.5 parts by mass or more and 30 parts by mass or less of the vinyl polymer (A) based on 100 parts by mass of the acrylic adhesive polymer (B) in terms of solid content. The blend ratio of the vinyl polymer to the acrylic adhesive polymer (B) is such that when the adhesive layer is obtained from the adhesive composition, the degree of segregation of the vinyl polymer (A) and the Tg ratio of the surface portion are adhered. The Tg of the entire agent layer is preferably set to be higher than 30 ° C. The lower limit of the vinyl polymer (A) is, for example, 0.8 parts by mass or more, and may be 1.0 part by mass or more. Further, the upper limit is, for example, 20 parts by mass or less, and may be 15 parts by mass or less. In addition, the content may be, for example, 0.8 parts by mass or more and 20 parts by mass or less, and may be 1.0 part by mass or more and 15 parts by mass or less. By using the amount of the vinyl polymer (A) to be 0.5 When the amount is more than the above, the durability is improved, and the effect of suppressing the swelling or peeling after heating and moist heat is sufficiently exhibited. When the amount is 30 parts by mass or less, the followability to the step shape can be improved. In addition, when it exceeds 30 parts by mass, it becomes difficult to maintain compatibility between the vinyl polymer (A) and the acrylic adhesive polymer (B), and phase separation tends to occur.

The glass transition temperature (Tg) of the entire adhesive layer obtained from the present adhesive composition is not particularly limited, and may be 0 ° C or lower, -10 ° C or lower, or -20 ° C or lower. When Tg is 0 ° C or less, sufficient adhesion can be exhibited. Moreover, the lower limit of Tg is -80 ° C from the viewpoint of restrictions on constituent monomers that can be obtained. Therefore, the Tg of the entire adhesive layer of the present invention may be in the range of -80 ° C or more and 0 ° C or less, the range of -80 ° C or more to -10 ° C or less, and the range of -70 ° C or more and -20 ° C or less.

In addition, the glass transition temperature of the entire adhesive layer means that the adhesive layer obtained from the adhesive composition containing the vinyl polymer (A) and the acrylic adhesive polymer (B) is used as a sample. The glass transition temperature obtained by a well-known method.

The adhesive layer can be obtained by subjecting the adhesive composition to a separator, drying or the like. According to the present adhesive composition, the Tg _s calculated from the composition of the surface portion obtained by X-ray photoelectron spectroscopy of the obtained adhesive layer can be made higher than the Tg _{b of the} entire adhesive layer. Above °C. When the difference between the Tg _s of the adhesive layer of the surface layer portion of the entire Tg _b (Tg _s -Tg _b) less than 30 ℃, for example, under a high temperature or 60 ℃ for 85 ℃ insufficient adhesive strength, an object of the present specification The durability or surface adhesion is not sufficient. The above (Tg _s -Tg _b ) may be 40 ° C or more and 50 ° C or more. The upper limit of the above (Tg _s -Tg _b ) is not particularly limited, but from the viewpoint of the Tg which can be obtained from the vinyl polymer (A) and the acrylic adhesive polymer (B), 230 ° C is the limit, and is generally 200. Below °C.

The "Tg calculated from the composition of the surface layer portion" as described above is obtained by the composition ratio of the vinyl polymer (A) and the acrylic adhesive polymer (B) obtained by X-ray photoelectron spectroscopy (XPS). Calculated and calculated. In the XPS, the generated photoelectrons are detected by irradiating X-rays to the surface of the adhesive layer, and composition information is obtained from the kinetic energy. The photoelectrons generated in the layer deep from the surface lose their kinetic energy before reaching the surface, so the detection depth in XPS is several nm. Therefore, composition information relating to the surface layer portion of about several nm from the surface of the adhesive layer can be obtained by XPS, and the vinyl polymer (A) and the acrylic adhesive polymer can be obtained based on the obtained composition information. The composition ratio of (B) can be calculated as Tg. Specific measurement conditions of XPS and methods for calculating Tg are described in the examples below.

The adhesive composition is provided on a 100 μm thick polyethylene terephthalate film substrate with an adhesive layer of an adhesive layer having a film thickness of 50 μm formed of the adhesive composition for a polycarbonate of 85 ° C. The bonding strength of the board (PC board) can also be set to 15 N/25 mm or more. Here, the above-mentioned adhesive strength means a 180° peel strength of a peeling speed of 300 mm/min. When the bonding strength of the PC plate at 85 ° C is 15 N/25 mm or more, the durability under high temperature and high humidity conditions of the PC plate and the tendency to bend the surface of the PC tend to increase. The above bonding strength can also be set to 20N/25mm on.

The adhesive composition is provided on a 100 μm thick polyethylene terephthalate film substrate with an adhesive sheet of an adhesive layer having a film thickness of 50 μm formed of the above-mentioned adhesive composition for a polypropylene plate of 85 ° C. The bonding strength of the (PP plate) may be set to 5.0 N/25 mm or more. Here, the above-mentioned adhesive strength means a 180° peel strength of a peeling speed of 300 mm/min. When the bonding strength of the PP plate at 85 ° C is 5.0 N/25 mm or more, there is a tendency that the durability of the PP plate under high temperature and high humidity conditions and the curved surface adhesion to PP tend to increase. The above bonding strength may be set to 7.0 N/25 mm or more.

When the adhesive sheet is produced, a method of directly applying an adhesive composition to a polyethylene terephthalate film substrate and drying it to obtain an adhesive sheet may be employed, or once applied to a release paper or the like, Any method of a method of transferring onto a polyethylene terephthalate film substrate.

The drying system can be carried out at room temperature, but from the viewpoint of productivity and the like, it is generally a method of drying in a drying machine under a heating condition of 40 to 150 ° C for several seconds to several tens of minutes.

Further, the measurement of the strength was carried out in accordance with JIS Z 0237 "Adhesive tape ‧ Adhesive sheet test method", and the adhesion strength to a polycarbonate plate or a polypropylene plate was measured under the conditions described in the column of Examples below.

The vinyl polymer (A) of the present invention has moderate compatibility with the acrylic adhesive polymer (B). Therefore, by containing this The adhesive layer obtained by the adhesive composition of the same shows good transparency, and at the same time, the vinyl polymer (A) is partially segregated in the adhesive layer, and the concentration ratio of the vinyl polymer (A) in the surface layer is present. Other parts have a higher tendency. When the concentration of the vinyl polymer (A) in the surface layer of the adhesive layer is higher than the others, even if the laminate of the adhesive sheet is attached to the transparent plastic substrate, the adhesive in the vicinity of the interface is followed. Since the layer has a relatively high Tg, the adhesion or peeling of the adhesive sheet due to the exhaust gas generated from the substrate is suppressed, and good durability is exhibited. Moreover, the adhesive layer as a whole has sufficient flexibility and can exhibit good adhesion properties. Further, even for the olefin-based adherend, good adhesion was exhibited.

The present adhesive composition is not particularly limited as long as it contains a predetermined amount of the vinyl polymer (A) and the acrylic adhesive polymer (B). For example, a method of mixing the vinyl polymer (A) and the acrylic adhesive polymer (B) may be an acrylic adhesive polymer (B) in the presence of the vinyl polymer (A). ) Those who are aggregated.

The adhesive composition of the present invention contains a vinyl polymer (A) and an acrylic adhesive polymer (B), and may contain a crosslinking agent (hardener), a tackifier, and a plasticizer as needed. A composition of an additive such as an antioxidant, an ultraviolet absorber, an anti-aging agent, a flame retardant, an antifungal agent, a decane coupling agent, a filler, a colorant, or the like.

The crosslinking agent (curing agent) may, for example, be an epoxy propyl compound having two or more epoxy propyl groups, an isocyanate compound having two or more isocyanate groups, or two or more aziridine groups. Aziridine compound, with Oxazoline An oxazoline compound, a metal chelate compound, a butylated melamine compound, or the like. Among these, an aziridine compound, a glycidyl compound, and an isocyanate compound can also be used.

Examples of the aziridine compound include 1,6-bis(1-aziridinecarbonylamino)hexane and 1,1'-(methylene-di-p-phenylene)bis-3. , 3-aziridine urea, 1,1'-(hexamethylene) bis-3,3-aziridine urea, ethyl bis-(2-aziridine propionate), three (1-Aziridine)phosphine oxide, 2,4,6-triaziridine-1,3,5-tri , trimethylolpropane-tris-(2-aziridine propionate), and the like.

Examples of the epoxy propylene compound include ethylene glycol diepoxypropyl ether, polyethylene glycol diepoxypropyl ether, propylene glycol diepoxypropyl ether, polypropylene glycol diepoxypropyl ether, and glycerin. Diepoxypropyl ether, neopentyl glycol diepoxypropyl ether, 1,6-hexanediol diepoxypropyl ether, tetraethoxypropyl xylene diamine, 1,3-double (N, N-diepoxypropylaminomethyl)cyclohexane, trimethylolpropane polyepoxypropyl ether, diglycerol polyepoxypropyl ether, polyglycerol polyepoxypropyl ether, sorbitol polycyclic ring A polyfunctional epoxy propyl compound such as oxypropyl ether.

As the above isocyanate compound, for example, a compound having two or more isocyanate groups can be used.

As the isocyanate compound, various isocyanate compounds of an aromatic type, an aliphatic type, and an alicyclic type, and a modified product (prepolymer or the like) of the above isocyanate compound can be used.

As the aromatic isocyanate, diphenylmethane II is exemplified. Isocyanate (MDI), crude diphenylmethane diisocyanate, toluene diisocyanate, naphthalene diisocyanate (NDI), p-phenylene diisocyanate (PPDI), xylene diisocyanate (XDI), tetramethyl benzene dimethyl Diisocyanate (TMXDI), tolidine diisocyanate (TODI), and the like.

Examples of the aliphatic isocyanate include hexamethylene diisocyanate (HDI), diazonic acid diisocyanate (LDI), and isocyanuric acid triisocyanate (LTI).

Examples of the alicyclic isocyanate include isophorone diisocyanate (IPDI), cyclohexyl diisocyanate (CHDI), hydrogenated XDI (H6XDI), and hydrogenated MDI (H12MDI).

Further, examples of the modified isocyanate include a urethane modified product, a dimer, a trimer, a carbodiimide modified product, an allophanate modified product, and a second modified product of the above isocyanate compound. Urea modified, urea modified, isomeric cyanurate modified, An oxazolidinone modified product, an isocyanate group terminal prepolymer, or the like.

When the adhesive composition of the present invention contains a crosslinking agent (curing agent), the content of the (meth)acrylic polymer may be 0.01 parts by mass or more and 10 parts by mass or less based on 100 parts by mass of the (meth)acrylic polymer. In addition, it may be 0.03 parts by mass or more and 5 parts by mass or less, and 0.05 parts by mass or more and 2 parts by mass or less.

Examples of the tackifier include rosin derivatives such as rosin ester, rosin gum, pine oil rosin, hydrogenated rosin ester, maleated rosin, and disproportionated rosin ester; terpene phenol resin, α-pinene, β- Terpene, limonene, etc. Terpene-based resin as a main component; (hydrogenated) petroleum resin; coumarone-anthraquinone resin; hydrogenated aromatic copolymer; styrene resin; phenol resin; xylene resin; (meth)acrylic polymer Wait.

Examples of the plasticizer include di-n-butyl phthalate, di-n-octyl phthalate, bis(2-ethylhexyl) phthalate, di-n-decyl phthalate, and phthalic acid. Phthalate esters such as oxime esters; adipates such as bis(2-ethylhexyl) ester and di-n-octyl adipate; bis(2-ethylhexyl) sebacate, bismuth a sebacate such as di-n-butyl acrylate; a sebacate such as bis(2-ethylhexyl) sebacate; a paraffin such as chlorinated paraffin; a glycol such as polypropylene glycol; Epoxidized vegetable oils such as oxidized soybean oil and epoxidized linseed oil; phosphates such as trioctyl phosphate and triphenyl phosphate; phosphites such as triphenyl phosphite; adipic acid and 1 , ester oligomers such as esters of 3-butanediol; low molecular weight polymers of low molecular weight polybutene, low molecular weight polyisobutylene, low molecular weight polyisoprene, etc.; processing oils, naphthenic oils, etc. Oil and so on.

Examples of the antioxidant include 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl 4-ethylphenol, and octadecyl-β-. (3,5-di-t-butyl-4-hydroxyphenyl)propionate, 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 2,2'- Methylene bis(4-ethyl-6-tert-butylphenol), 4,4'-thiobis(3-methyl-6-tert-butylphenol), 4,4'-butylene double (3-methyl-6-tert-butylphenol), 3,9-bis[1,1-dimethyl-2-[β-(3-tert-butyl-4-hydroxy-5-methyl) Phenyl)propenyloxy]ethyl]2,4,8,10-tetraspiro[5.5]undecane, 1,3-tris(2-methyl-4-hydroxy-5-t-butylbenzene Butane, 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, tetrakis[methylene-3-( 3',5'-di-t-butyl-4'-hydroxyphenyl)propionate]methane, bis[3,3'-bis-(4'-hydroxy-3'-tert-butylphenyl) Butyrate]ethylene glycol ester, 1,3,5-tris(3',5'-di-t-butyl-4'-hydroxybenzyl)-S-three a phenolic antioxidant of -2,4,6-(1H,3H,5H)trione, tocopherol, etc.; dilauryl 3,3'-thiodipropionate, dimyristyl 3,3' a sulfur-based antioxidant such as thiodipropionate or octadecyl 3,3'-thiodipropionate; triphenyl phosphite, diphenylisodecyl phosphite, 4,4'-Adenine Base-bis(3-methyl-6-t-butylphenyl bistridecyl) phosphite, cyclic neopentane tetrayl bis(octadecyl phosphite), tris(nonylphenyl) phosphite Ester), tris(monodecylphenyl) phosphite, tris(diphenylphenyl) phosphite, diisodecyl pentaerythritol diphosphite, 9,10-dihydro-9-oxa- 10-phosphaphenanthrene-10-oxide, 10-(3,5-di-t-butyl-4-hydroxybenzyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxidation , 10-methoxyl-9,10-dihydro-9-oxa-10-phosphaphenanthrene, tris(2,4-di-t-butylphenyl)phosphite, cyclic neopentane tetrayl Bis(2,4-di-t-butylphenyl)phosphite, cyclic neopentyltetrakis(2,6-di-t-butyl-4-methylphenyl)phosphite, 2, A phosphorus-based antioxidant such as 2-methylenebis(4,6-di-t-butylphenyl)octylphosphite.

Examples of the ultraviolet absorber include a salicylic acid-based ultraviolet absorber such as phenyl salicylate, t-butylphenyl salicylate, or p-octylphenyl salicylate; and 2,4-dihydroxy group; Phenyl ketone, 2-hydroxy-4-methoxydiphenyl ketone, 2-hydroxy-4-octyloxydiphenyl ketone, 2-hydroxy-4-dodecyloxydiphenyl ketone, 2, 2'-dihydroxy-4-methoxydiphenyl ketone, 2,2'-di Hydroxy-4,4'-dimethoxydiphenyl ketone, 2-hydroxy-4-methoxy-5-sulfodiphenyl ketone, bis(2-methoxy-4-hydroxy-5-benzene a diphenyl ketone ultraviolet absorber such as formazan phenyl)methane; 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-5'- Tert-butylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-t-butylphenyl)benzotriazole, 2-(2'-hydroxy-3'- Third butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-t-butylphenyl)-5-chlorobenzotriene Oxazole, 2-(2'-hydroxyester-3',5'-di-third-pentylphenyl)benzotriazole, 2-(2'-hydroxy-4'-octyloxyphenyl)benzotriene Azole, 2-[2'-hydroxy-3'-(3",4",5",6"-tetrahydrophthaleneiminemethyl)-5'-methylphenyl]benzotrien Oxazole, 2,2-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazol-2-yl)phenol], 2-(2 '-Hydroxy-5'-methacryloxylphenyl)-2H-benzotriazole, 2,2'-methylenebis[4-(1,1,3,3-tetramethylbutyl) a benzotriazole-based ultraviolet absorber of 6-(2H-benzotriazol-2-yl)phenol]; 2-ethylhexyl-2- a cyanoacrylate ultraviolet absorber such as cyano-3,3'-diphenyl acrylate or ethyl-2-cyano-3,3'-diphenyl acrylate; bis(octylphenyl) Nickel sulfide, [2,2'-thiobis(4-tert-octylphenolate)]-n-butylamine nickel, nickel complex-3,5-di-t-butyl-4-hydroxybenzyl a nickel-based ultraviolet stabilizer such as a monoethanolate phosphate or a nickel dibutyldithiocarbamate.

As the above anti-aging agent, poly(2,2,4-trimethyl-1,2-dihydroquinoline), 6-ethoxy-1,2-dihydro-2,2,4- Trimethylquinoline, 1-(N-phenylamino)-naphthalene, styrenated diphenylamine, dialkyldiphenylamine, N,N'-diphenyl-p-phenylenediamine, N- phenyl-N'-isopropyl-p-phenylene Amine, N, N'-di-2-naphthyl p-phenylenediamine, 2,6-di-t-butyl-4-methylphenol, mono(α-methylbenzyl)phenol, di(α-甲Benzyl)phenol, tris(α-methylbenzyl)phenol, 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 2,2'-methylene double (4-ethyl-6-tert-butylphenol), 4,4'-butylene bis(6-tert-butyl-3-methylphenol), 4,4'-thiobis (6- Tributyl-3-methylphenol), 1,1-bis(4-hydroxyphenyl)cyclohexane, 2,5-di-t-butylhydroquinone, 2,5-di-p-pentylhydroquinone , 2-mercaptobenzimidazole, zinc salt of 2-mercaptobenzimidazole, 2-mercaptomethylbenzimidazole, nickel dibutyldithiocarbamate, tris(nonylphenyl)phosphite, sulfur Dilauryl dipropionate, octadecyl thiodipropionate, and the like.

Examples of the flame retardant include tetrabromobisphenol A, 2,2-bis(4-hydroxy-3,5-dibromophenyl)propane, hexabromobenzene, and tris(2,3-dibromopropyl). Is difficult to use halogens such as isomeric cyanurate, 2,2-bis(4-hydroxyethoxy-3,5-dibromophenyl)propane, decabromodiphenyl oxide, halogen-containing polyphosphate, etc. Combustion agent; ammonium phosphate, tricresyl phosphate, triethyl phosphate, tris(β-chloroethyl) phosphate, trichloroethyl phosphate, three dichloropropyl phosphates, tolyldiphenyl phosphate, phosphoric acid Phosphorus-based flame retardant such as tolyldiphenyl ester, acid phosphate, or nitrogen-containing phosphorus compound; inorganic substance such as red bismuth, tin oxide, antimony trioxide, zirconium hydroxide, barium metaborate, aluminum hydroxide, magnesium hydroxide, etc. a flame retardant; such as poly(dimethoxy methoxy), poly(diethoxy siloxane), poly(diphenoxy siloxane), poly (methoxy phenoxy oxane) ), a methyl decanoate, an ethyl decanoate, a decyl phthalate phthalate-based flame retardant, and the like.

Examples of the above-mentioned antifungal agent include benzimidazole and benzothiazide. An azole, a trihaloallyl, a triazole, an organic nitrogen sulfur compound, and the like.

Examples of the above decane coupling agent include vinyltriethoxydecane, vinyltris(β-methoxyethoxy)decane, γ-methylpropenyloxypropyltrimethoxydecane, and vinyl trisole. Ethoxylated decane, γ-glycidoxypropyltrimethoxydecane, γ-glycidoxypropyltriethoxydecane, β-(3,4-epoxycyclohexyl)ethyl Trimethoxy decane, γ-chloropropyl methoxy decane, vinyl trichloro decane, γ-mercaptopropyl trimethoxy decane, γ-aminopropyl triethoxy decane, N-β (amino group B )--aminopropyltrimethoxydecane, and the like.

Examples of the filler include inorganic powder fillers such as calcium carbonate, titanium oxide, mica, and talc; and fibrous fillers such as glass fibers and fibers for organic reinforcing.

The adhesive composition of the present invention is not particularly limited as long as it contains the above vinyl polymer (A) and the acrylic adhesive polymer (B). For example, it can be used as a solvent-based adhesive composition dissolved in an organic solvent such as ethyl acetate, or as an emulsion-type adhesive in which an acrylic adhesive polymer and a vinyl polymer are dispersed in an aqueous medium. The form of the composition is used.

In the case of the above-mentioned solution type adhesive composition and the emulsion type adhesive composition, the medium of the organic solvent or water to be used is usually 20 to 80 parts by mass based on 100 parts by mass of the adhesive composition.

When used as an emulsion type adhesive, it can be blended with a stabilizer. Examples of the stabilizer include cadmium stearate, zinc stearate, and stearic acid. Hydrazine, calcium stearate, lead dibutyltin dilaurate, tris(nonylphenyl) phosphite, triphenyl phosphite, diphenylisodecyl phosphite, stabilizers for vinyl chloride; di-n-octyl bis-bis (isooctylmercaptoacetate) salt, di-n-octyltin maleate polymer, di-n-octyltin dilaurate, di-n-octyltin maleate, di-n-butyltin bismale Acid ester salt, di-n-butyltin maleate polymer, di-n-butyltin bis octyl thioglycolate, di-n-butyltin β-mercaptopropionate polymer, di-n-butyltin dilaurate, di-n-methyl Tin bis(isooctyl decyl acetate) salt, poly(thiobis-n-butyltin sulphate), monooctyltin tris(isooctyl decyl acetate), dibutyltin maleate, di-n-butyltin apple Organic tin-based stabilizers such as acid esters, carboxylic acid esters, and di-n-butyltin malate ‧ thiolates; tribasic lead sulfate, dibasic lead phosphite, basic lead sulfite, dibasic benzene Lead-based stabilizers such as lead formate, lead citrate, lead dibasic stearate, lead stearate, etc.; cadmium soap, zinc soap, lanthanum soap, lead soap, complex A metal soap stabilizer such as a combined metal soap or calcium stearate.

Further, the adhesive composition of the present invention comprises a monofunctional and/or polyfunctional (meth)acrylic acid in addition to the above vinyl polymer (A) and the above acrylic adhesive polymer (B). A composition such as a monomer and a photopolymerization initiator can be used as a so-called slurry-type photocurable adhesive composition which is cured by active energy such as ultraviolet rays.

In the case of the photocurable adhesive composition, the composition may contain an organic solvent or the like, but is generally used as a solventless type containing no solvent.

Examples of the monofunctional (meth)acrylic monomer include alkyl (meth)acrylates having an alkyl group having 1 to 12 carbon atoms; cyclohexyl (meth)acrylate and (meth)acrylic acid a (meth) acrylate having a cyclic structure such as cyclopentyl ester or isobornyl (meth)acrylate; hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, or (meth) acrylate a hydroxyalkyl (meth)acrylate such as butyl ester; (meth)acrylic acid or the like. These compounds may be used singly or in combination of two or more.

Examples of the polyfunctional (meth)acrylic monomer include di(meth)acrylates of alkylene glycols such as butanediol di(meth)acrylate and hexanediol di(meth)acrylate. Di(meth)acrylates of polyalkylene glycols such as di(meth)acrylates of triethylene glycol; trimethylolpropane tri(meth)acrylate and its ethylene oxide and/or Or a propylene oxide modified product, pentaerythritol tri(meth) acrylate, pentaerythritol tetra (meth) acrylate, or the like. Further, a polymer (macromonomer) having a (meth) acrylonitrile group such as a polyurethane (meth) acrylate or a polyisoprene (meth) acrylate may also be used. Specific examples of the polyisoprene-based (meth) acrylate are, for example, a maleic anhydride adduct of an isoprene polymer and an esterified product of 2-hydroxyethyl methacrylate. These compounds may be used singly or in combination of two or more.

Examples of the photopolymerization initiator include benzoin and its alkyl ethers, acetophenones, anthraquinones, thioxanthones, ketals, diphenylketones, xanthones, and anthraquinones. Phosphine oxides, α-diketones, and the like.

Further, in order to increase the sensitivity of the active energy ray, a photosensitizer may be used in combination.

Examples of the photosensitizer include a benzoic acid-based and an amine-based photosensitizer. These can also be used in combination of 2 or more types.

The amount of the photopolymerization initiator and the photosensitizer to be used may be 0.01 parts by mass or more and 10 parts by mass or less based on 100 parts by mass of the monofunctional and/or polyfunctional (meth)acrylic monomer.

Further, as the photocurable adhesive composition described above, the vinyl polymer (A), the monofunctional and/or polyfunctional (meth)acrylic monomer, and photopolymerization may be further included. A photocurable adhesive composition comprising a composition of a starting agent is used. In the photocurable adhesive composition, the acrylic adhesive polymer (B) may be mixed as needed.

The adhesive composition of the present invention can also be applied to various types of adhesive films, adhesive sheets, adhesive tapes, adhesive labels, pressure-sensitive adhesive tapes, surface protective films, surface protective tapes, masking tapes, electrical insulating tapes, laminates, and the like. Adhesive products, and various optical films, etc., which are used for lamination.

When the adhesive composition of the present invention is applied to one or both sides of various substrates, the adhesive composition of the present invention is formed by adhering or irradiating an active energy ray such as UV to form an adhesive layer. Adhesive products such as sheets or adhesive tape. Further, after the composition is in a molten state and applied to a substrate, it is also possible to obtain a product having an adhesive layer by cooling.

As the substrate, paper, film, cloth, non-woven fabric, metal foil, or the like can be used, and the application of the adhesive composition can be directly performed on the substrate, or coated on a release paper or the like, after drying. Transfer to the substrate.

The thickness of the adhesive formed on the adhesive sheet (thickness after drying) is selected according to the application, but it is usually in the range of 1 to 300 μm, and may be in the range of 5 to 250 μm and in the range of 10 to 200 μm.

Further, by using a glass plate and/or a transparent plastic plate in the substrate, an adhesive product obtained by laminating a glass plate and/or a transparent plastic plate on one or both sides of the adhesive layer can be obtained. This adhesive processed product can be suitably used as a laminate of various optical films and the like. In this case, the coating of the adhesive composition may be carried out directly on the substrate, or may be applied to a release paper or the like, and transferred to the substrate after drying.

The adhesive composition of the present invention is excellent in transparency and moist heat whitening property, and has high adhesiveness and adhesive strength to various adherends including glass, and is therefore suitable for a touch panel, a liquid crystal display device, and an organic A display of an EL display device, a plasma display panel, or the like, and a combination of various optical films used therefor. Moreover, it is also applicable to the subsequent use in electronic parts, such as a flexible circuit board.

[Examples]

Hereinafter, the present invention will be specifically described on the basis of the examples. Further, the present invention is not limited by the following examples. In the following description, "parts" means parts by mass, and "%" means mass%.

Moreover, various analyses of the polymers obtained in this example were carried out by the following The method described is implemented.

<solid content>

Weighing (a) About 1 g of the sample was measured, and then the residue (b) after drying at 155 ° C for 30 minutes in a ventilating dryer was measured and calculated by the following formula. Use a graduated bottle for the measurement. Other operations are based on JIS K 0067-1992 (Chemical Deduction and Residue Test Method).

Solid content (%) = (b/a) × 100

<Molecular weight determination>

The molecular weight was measured by GPC under the following conditions.

GPC: Tosoh (HLC-8120)

Pipe column: Tosoh (TSKgel-Super MP-M×4)

Sample concentration: 0.1%

Flow rate: 0.6ml/min

Eluent: tetrahydrofuran

Column temperature: 40 ° C

Detector: Differential Refractometer (RI)

Reference material: polystyrene

<glass transition point (Tg)>

The Tg of the vinyl polymer (A), the acrylic adhesive polymer (B), and the entire adhesive layer was measured by DSC under the following conditions.

DSC: TA Instrument System (Q-100)

Heating temperature: 10 ° C / min

Measuring environment: nitrogen

<Polymer composition>

The polymer composition was calculated from the amount of monomer added and the amount of monomer consumed by GC.

GC: Agilent Technolosies (7820A GC System)

Detector: FID

Column: 100% dimethyloxane (CP-Sil 5CB), length 30m, inside Trail 0.32mm

Calculation method: internal standard method

1. Synthesis of vinyl polymers

Synthesis Example 1 (Synthesis of Polymer A-1)

1,4-butyl acetate (198 parts by mass) and dimethyl 2,2'-azobis (2-methyl propionate) were added to a four-liter flask containing 1 liter of internal volume (trade name, Wako Pure Chemical Industries, Ltd.) The mixed liquid composed of "V-601") (4.4 parts by mass) was sufficiently degassed by bubbling of nitrogen gas to raise the internal temperature of the mixture to 90 °C. In addition, methyl methacrylate (hereinafter referred to as "MMA") (141 parts by mass), isobornyl methacrylate (hereinafter referred to as "IBXMA") (110 parts by mass), V-601 (84 mass) The mixture of butyl acetate (90 parts by mass) was dropped from the dropping funnel into the flask for 5 hours to carry out polymerization. After the completion of the dropwise addition, the polymerization solution was dropped to methanol (4800 parts by mass). In a mixed solution composed of distilled water (1200 parts by mass), the vinyl polymer in the polymerization solution was isolated to obtain a polymer A-1. The polymer composition of the obtained polymer A-1 was calculated from the amount of the monomer and the amount of monomer consumed by GC. The result was composed of MMA 59% by mass and IBXMA 41% by mass, Mw2520, Mn1900, and Mw/Mn 1.33. The Tg was 77 °C.

The composition and analysis results of the polymer A-1 are shown in Table 1.

Synthesis Example 2 (Synthesis of Polymer A-2)

Synthesis Example 2 (Polymer A-2)

A mixture of butyl acetate (198 parts by mass) and V-601 (3.6 parts by mass) was added to a four-liter flask having an internal volume of 1 liter, and the mixture was sufficiently taken off by bubbling of nitrogen gas. Gas, the internal temperature of the mixture was raised to 90 °C. Further, a mixture of MMA (200 parts by mass), IBXMA (56 parts by mass), V-601 (69 parts by mass), and butyl acetate (90 parts by mass) was dropped from the dropping funnel for 5 hours. Polymerization was carried out into the flask. After the completion of the dropwise addition, the polymer A-2 was obtained by separating the polymerization solution into hexane (6000 parts by mass) to separate the vinyl polymer in the polymerization solution.

The composition and analysis results of the polymer A-2 are shown in Table 1.

Synthesis Example 3 (Synthesis of Polymer A-3)

A mixture of butyl acetate (198 parts by mass) and V-601 (1.2 parts by mass) was added to a four-liter flask having an internal volume of 1 liter, and the mixture was sufficiently taken off by bubbling of nitrogen gas. Gas, make the mixture inside The temperature rises to 90 °C. Further, a mixture of MMA (165 parts by mass), IBXMA (44 parts by mass), V-601 (23 parts by mass), and butyl acetate (90 parts by mass) was dropped from the dropping funnel for 5 hours. Polymerization was carried out into the flask. After the completion of the dropwise addition, the polymer A-3 was obtained by separating the polymerization solution into hexane (6000 parts by mass) to separate the vinyl polymer in the polymerization solution.

The composition and analysis results of the polymer A-3 are shown in Table 1.

Synthesis Example 4 (Synthesis of Polymer A-4)

In a four-necked flask having an internal volume of 1 liter, MMA (35 parts by mass), styrene (hereinafter referred to as "St") (5 parts by mass), butyl acetate (198 parts by mass), and V-601 (7.5) were added. The mixed liquid composed of the mass parts was sufficiently degassed by bubbling of nitrogen gas to raise the internal temperature of the mixed liquid to 90 °C. Further, a mixture of MMA (158 parts by mass), St (47 mass), V-601 (68 parts by mass), and butyl acetate (90 parts by mass) was dropped from the dropping funnel for 5 hours. The polymerization was carried out in a flask. After the completion of the dropwise addition, the polymerization solution was dropped into a mixed solution composed of methanol (4800 parts by mass) and distilled water (1200 parts by mass) to separate the vinyl polymer in the polymerization solution to obtain a polymer A-4. .

The composition and analysis results of the polymer A-4 are shown in Table 1.

Synthesis Example 5 (Synthesis of Polymer A-5)

In a four-neck flask with an internal volume of 1 liter, add by MMA (19 quality a mixture of St (11 parts by mass), butyl acetate (224 parts by mass), and V-601 (8.7 parts by mass), which was sufficiently degassed by bubbling of nitrogen gas. The internal temperature of the mixture was raised to 90 °C. Further, a mixture of MMA (108 parts by mass), St (93 parts by mass), V-601 (78 parts by mass), and butyl acetate (90 parts by mass) was dropped from the dropping funnel for 5 hours. Polymerization was carried out into the flask. After the completion of the dropwise addition, the polymerization solution was dropped into a mixed solution composed of methanol (4200 parts by mass) and distilled water (1800 parts by mass) to separate the vinyl polymer in the polymerization solution to obtain a polymer A-5. .

The composition and analysis results of the polymer A-5 are shown in Table 1.

Synthesis Example 6 (Synthesis of Polymer A-6)

A mixture of MMA (40 parts by mass), St (6 parts by mass), butyl acetate (250 parts by mass), and V-601 (2.5 parts by mass) was placed in a four-neck flask having an internal volume of 1 liter. The mixture was sufficiently degassed by bubbling of nitrogen gas to raise the internal temperature of the mixture to 90 °C. Further, a mixture of MMA (161 parts by mass), St (43 parts by mass), V-601 (22 parts by mass), and butyl acetate (90 parts by mass) was dropped from the dropping funnel for 5 hours. Polymerization was carried out into the flask. After the completion of the dropwise addition, the polymerization solution was dropped into a mixed solution composed of methanol (4200 parts by mass) and distilled water (1800 parts by mass) to separate the vinyl polymer in the polymerization solution to obtain a polymer A-6. .

The composition and analysis results of the polymer A-6 are shown in Table 1.

Synthesis Example 7 (Synthesis of Polymer A-7)

A mixture of MMA (63 parts by mass), butyl acetate (250 parts by mass), and V-601 (4.2 parts by mass) was added to a four-liter flask having an internal volume of 1 liter, and bubbling with nitrogen gas was carried out. The mixture was thoroughly degassed to raise the internal temperature of the mixture to 90 °C. In addition, a mixed liquid composed of MMA (188 parts by mass), V-601 (46 parts by mass), and butyl acetate (90 parts by mass) was dropped from the dropping funnel into the flask for 5 hours to carry out polymerization. After the completion of the dropwise addition, the polymer solution was obtained by dropping the polymerization solution into hexane (6000 parts by mass) to separate the vinyl polymer in the polymerization solution.

The composition and analysis results of the polymer A-7 are shown in Table 1.

Synthesis Example 8 (Synthesis of Polymer A-8)

A mixture of butyl acetate (250 parts by mass) and V-601 (0.1 parts by mass) was added to a four-liter flask having an internal volume of 1 liter, and the mixture was sufficiently taken off by bubbling of nitrogen gas. Gas, the internal temperature of the mixture was raised to 90 °C. Further, a mixture of MMA (200 parts by mass), St (56 parts by mass), V-601 (2.2 parts by mass), and butyl acetate (90 parts by mass) was dropped from the dropping funnel for 5 hours. Polymerization was carried out into the flask. After the completion of the dropwise addition, the polymerization solution was dropped into a mixed solution composed of methanol (4200 parts by mass) and distilled water (1800 parts by mass), and the vinyl polymer in the polymerization solution was isolated to obtain a polymer A-8. .

The composition and analysis results of the polymer A-8 are shown in Table 1.

The details of the compounds used in Table 1 are shown below.

MMA: Methyl methacrylate

St: Styrene

IBXMA: Isobornyl Methacrylate

2. Synthesis of acrylic adhesive polymer

Synthesis Example 9 (synthesis of polymer B-1)

In a four-necked flask having an internal volume of 2 liters, methoxyethyl acrylate (hereinafter referred to as "MEA") (285 parts by mass) and 2-hydroxyethyl acrylate (hereinafter referred to as "HEA") (15 parts by mass) were added. Ethyl acetate (520 parts by mass), the mixture was sufficiently degassed by bubbling of nitrogen gas, the internal temperature of the mixture was raised to 40 ° C, and azobisvaleronitrile was added (hereinafter referred to as "V" -65") (11.5 parts by mass) to start polymerization. After 4 hours, the polymer B-1 was obtained by dropping the polymerization solution into hexane (10,000 parts by mass) to separate the acrylic adhesive polymer. Aggregated The substance B-1 was composed of 95% by mass of MEA and 5 mass% of HEA, and Mw was 500,000, Mn was 70,000, and Mw/Mn was 7.1.

Synthesis Example 10 (Synthesis of Polymer B-2)

MEA (285 parts by mass), acrylic acid (hereinafter referred to as "AA") (15 parts by mass), and ethyl acetate (520 parts by mass) were added to a four-necked flask having an internal volume of 2 liters, and bubbling with nitrogen gas was carried out. The mixture was thoroughly degassed, the internal temperature of the mixture was raised to 40 ° C, and V-65 (11.5 parts by mass) was added to initiate polymerization. After 4 hours, the polymer B-2 was obtained by dropping the polymerization solution into hexane (10,000 parts by mass) to separate the acrylic adhesive polymer. The obtained polymer B-2 was composed of 95% by mass of MEA and 5% by mass of AA, and Mw was 490,000, Mn was 70,000, and Mw/Mn was 6.8.

Synthesis Example 11 (Synthesis of Polymer B-3)

MEA (239 parts by mass), butyl acrylate (hereinafter referred to as "BA") (19 parts by mass), HEA (15 parts by mass), and ethyl acetate (520 parts by mass) were placed in a four-necked flask having an internal volume of 2 liters. The mixture was sufficiently degassed by bubbling of nitrogen gas to raise the internal temperature of the mixture to 40 ° C, and V-65 (11.4 parts by mass) was added to initiate polymerization. After 4 hours, the polymer B-3 was obtained by dropping the polymerization solution into hexane (10,000 parts by mass) to separate the acrylic adhesive polymer. The obtained polymer B-3 was composed of MEA 88% by mass, BA 7 mass%, and HEA 5 mass%, Mw 510,000, Mn 80,000, and Mw/Mn6.4.

Synthesis Example 12 (Synthesis of Polymer B-4)

MEA (217 parts by mass), BA (41 parts by mass), HEA (15 parts by mass), and ethyl acetate (520 parts by mass) were added to a four-liter flask having an internal volume of 2 liters, and bubbling with nitrogen gas was carried out. The mixture was sufficiently degassed, the internal temperature of the mixture was raised to 40 ° C, and V-65 (11.4 parts by mass) was added to initiate polymerization. After 4 hours, the polymerization solution was dropped into hexane (10,000 parts by mass) to separate the acrylic adhesive polymer, thereby obtaining a polymer B-4. The obtained polymer B-4 was composed of 80% by mass of MEA, 155% by mass of BA, and 55% by mass of HEA, and had Mw of 500,000, Mn of 70,000 and Mw/Mn of 7.2.

3. Manufacture and evaluation of adhesive composition

Example 1

The polymer (A-1) obtained in the above Synthesis Example 1 was dissolved in ethyl acetate to prepare a polymer (A-1) solution having a solid concentration of 30% by mass. In the same manner, the polymer (B-1) obtained in the above Synthesis Example 9 was dissolved in ethyl acetate to prepare a polymer (B-1) solution having a solid concentration of 30% by mass. 2 parts by mass of the polymer (A-1) solution, a polymer B-1 solution (100 parts by mass), and a Coronate L45 (manufactured by Nippon POLYURETHANE INDUSTRIAL CO., LTD.) (0.27 parts by mass) as a crosslinking agent were mixed to obtain an adhesive. Composition.

The adhesive composition was applied to a polyethylene terephthalate (hereinafter referred to as "PET") separator having a thickness of 38 μm so that the thickness after drying was 50 μm. Drying the adhesive composition at 80 ° C 4 In the minute, the ethyl acetate was removed, and the crosslinking reaction was carried out, and a PET separator having a thickness of 38 μm which was different from the separator was bonded thereto, and aging was carried out by standing at 40 ° C for 5 days to obtain a double. Adhesive film sample with a separator attached to the surface.

The obtained adhesive film sample was subjected to various measurements and evaluations by the methods shown below. The results obtained are shown in Table 2.

<gel fraction>

0.2 g of the adhesive was collected from the adhesive film sample, and the initial weight of the adhesive was weighed. The adhesive was immersed in 50 g of ethyl acetate, and allowed to stand at room temperature for 16 hours. Then, the mixture was filtered through a metal mesh of 200 mesh, and the residue remaining on the net was dried at 80 ° C for 3 hours, and weighed. From the initial weight and the weight of the residue, the gel fraction based on the acrylic adhesive polymer (B) was calculated by the following formula.

[Number 1] Gel fraction (%) = (weight of residue) / [(initial weight) × (solid content of acrylic adhesive polymer (B)) / (solid content of the entire adhesive composition) )]×100

<For peeling strength of polycarbonate (PC) and polypropylene (PP)>

The adhesive film sample was transferred onto a PET film (100 μm) which was easily treated, and an adhesive sheet for evaluation was obtained. Attached to PC board (Mitsubishi Gas Chemical Co., Ltd., Iupiron NF-2000, 2mm thick) or PP board (Sumitomo Chemical, Sumitomo Nobrene MH8, 2mm thick), conforming to the adhesive sheet for the above evaluation, using the desktop pressure defoaming device TBR-200 (manufactured by Chiyoda Electric Industrial Co., Ltd.), and pressed at a temperature of 0.5 MPa and 50 °C for 20 minutes, and then a tensile tester Strograph R (manufactured by Toyo Seiki Co., Ltd.) equipped with a thermostatic chamber at 23 ° C, 60 ° C and 85 ° Under the condition of °C, the 180-degree peel strength of the adhesive sheet was measured in accordance with JIS Z-0237 "Adhesive tape ‧ adhesive sheet test method", and the joint strength was measured. Also, the peeling speed was 300 mm/min.

<For the strength of COP>

The adhesive film sample was transferred onto a PET film (100 μm) which was easily treated, and an adhesive sheet for evaluation was obtained. A COP film (Zeonor ZF-14 100 μm, manufactured by Japan Zeon Co., Ltd.) was attached to a polymethyl methacrylate plate to form an attached body, and the adhesive sheet for evaluation described above was attached thereto, and a bench pressurization defoaming device TBR-200 was used. (manufactured by Chiyoda Electric Industrial Co., Ltd.), and pressed at a temperature of 0.5 MPa and 50 °C for 20 minutes, and then a tensile tester Strograph R (manufactured by Toyo Seiki Co., Ltd.) equipped with a thermostatic chamber at 23 ° C, 60 ° C and 85 ° Under the condition of °C, the 180-degree peel strength of the adhesive sheet was measured in accordance with JIS Z-0237 "Adhesive tape ‧ adhesive sheet test method", and the joint strength was measured. Also, the peeling speed was 300 mm/min.

<Tg of the surface layer portion of the adhesive layer>

Calculating the peak area ratio of O1s to C1s measured by X-ray photoelectron spectroscopy (XPS) of the self-adhesive film sample, and calculating the vinyl polymer (A) and the acrylic adhesive polymer in the surface layer portion of the adhesive layer The total amount of (B), the mass fraction (w _A and w _B ) of the vinyl polymer (A) and the acrylic adhesive polymer (B), and the Tg of the surface layer portion was calculated according to the formula of FOX.

Further, the XPS measurement was measured under the following conditions.

Device: PHI5000 VersaProbe made by ULVAC-PHI

X-ray: Al-Kα (1486.6eV)

X-ray incident angle of the sample: 0° (angle for the normal of the measurement surface of the sample)

Photoelectron detection angle: 45° (angle for the normal of the measurement surface of the sample)

The specific calculation method of the above-mentioned mass fraction is described below.

The ratio of the number of oxygen atoms to the number of carbon atoms calculated from the peak area ratio of O1s to C1s measured by XPS is as follows (1), and the vinyl polymer (A) and the acrylic adhesive polymer (B) The ratio of the number of oxygen atoms per unit weight of the surface layer portion of the adhesive layer formed by the adhesive composition composed of the adhesive composition to the number of carbon atoms.

Here,

(O/C) _A+B : ratio of oxygen atom number to carbon number calculated from XPS measurement of the adhesive layer obtained by drying the adhesive composition

W _A : mass fraction of vinyl polymer (A) relative to the total amount of vinyl polymer (A) and acrylic adhesive polymer (B)

M _WA : weighted average molecular weight of all constituent monomer units of the vinyl polymer (A)

M _WB : weighted average molecular weight of all constituent monomer units of the acrylic adhesive composition (B)

N _OA : the number of oxygen atoms contained in the average monomer structural formula of all the constituent monomers constituting the vinyl polymer (A)

N _OB : the number of oxygen atoms contained in the average monomer structural formula of all the constituent monomers constituting the acrylic adhesive polymer (B)

N _CA : the number of carbon atoms contained in the average monomer structural formula of all the constituent monomers constituting the vinyl polymer (A)

N _CB : the number of carbon atoms contained in the average monomer structural formula of all the constituent monomers constituting the acrylic adhesive polymer (B)

Further, the carbon atom calculated from the peak area ratio of O1s to C1s obtained by XPS measurement of the film obtained by drying each of the vinyl polymer (A) and the acrylic adhesive polymer (B) The ratio of the number to the number of oxygen atoms is represented by the following formulas (2) and (3).

Here,

(O/C) _A : ratio of the number of oxygen atoms to the number of carbon atoms calculated from the peak area ratio of O1s to C1s obtained by XPS measurement of the film obtained by drying the vinyl polymer (A)

Here,

(O/C) _B : ratio of the number of oxygen atoms to the number of carbon atoms calculated from the peak area ratio of O1s to C1s obtained by XPS measurement of the film obtained by drying the acrylic adhesive polymer (B)

The following formula (4) is derived from the above formulas (1) to (3), thereby calculating the total amount of the vinyl polymer (A) and the acrylic adhesive polymer (B), and the vinyl polymer ( A) Mass fraction (W _A ).

In addition, the mass fraction (W _B ) of the acrylic adhesive polymer (B) was calculated from the value of W _A obtained above and the following formula (5).

[Number 5] W _B =1- W _A (5)

Here,

W _B : mass fraction of the acrylic adhesive polymer (B) relative to the total amount of the vinyl polymer (A) and the acrylic adhesive polymer (B)

With respect to Example 1, each element in the above formula (4) is shown below.

(O/C) _A+B : 0.260 (measured value)

(O/C) _A : 0.252 (measured value)

(O/C) _B : 0.439 (measured value)

N _CA : According to the number of carbon atoms in the MMA1 molecule (5), the number of carbon atoms in the IBXMA1 molecule (14), and the composition ratio, 5 × 76.1 (mol%) + 14 × 23.9 (mol%) = 7.15

N _CB : According to the number of carbon atoms in the MEA1 molecule (6), the number of carbon atoms in the HEA1 molecule (5), and the composition ratio, 6 × 94.4 (mol%) + 5 × 5.6 (mol%) = 5.94

M _WA : According to MMA molecular weight (100), IBXMA molecular weight (222) and composition ratio, 100 × 76.1 (mol%) + 222 × 23.9 (mol%) = 129.2

M _WB : according to the molecular weight of the MEA (130), the molecular weight of the HEA (116), and the composition ratio, 130 × 94.4 (mol%) + 116 × 5.6 (mol%) = 129.2

By substituting the values of these values into the formula (4), W _A = 0.95 is obtained, and W _B = 0.05 is obtained from the formula (5).

Next, from the surface composition obtained by the measurement, the Tg of the surface layer portion was calculated according to the formula of FOX represented by the following formula (6) to obtain 69.4. The value of °C.

1/[Tg of surface layer] (K)=W _A /Tg _A +W _B /Tg _B (6)

Here,

Tg _A : Tg of vinyl polymer (A) (77 ° C)

Tg _B : Tg of acrylic adhesive polymer (B) (-31 ° C)

<Durability>

A PET film having a thickness of 100 μm and a post-processed PET film was attached to one surface of the adhesive film sample, and a laminate of a polycarbonate plate was attached to the other surface, and the laminate was subjected to 50° C. and 0.5 MPa. 20 minutes of compression treatment. Then, the laminate was subjected to a load for 24 hours in a constant temperature and humidity chamber of 60° C./95% RH or 85° C./85%, and the appearance after the load (with or without foaming) was visually confirmed, and evaluated according to the following criteria.

○: no appearance change

△: The area of the portion where foaming occurred was 10% or less with respect to the area of the test piece

×: The area of the portion where foaming occurred exceeded 10% with respect to the area of the test piece

<Compatibility of Vinyl Polymer (A) with Acrylic Adhesive Polymer (B)>

The release film on one side was peeled off from the adhesive film sample, transferred to a glass plate having a thickness of 1 mm, and the release film on the other side was peeled off. Put this at 23 After allowing to stand for one day at a temperature of 50% RH, the haze value was evaluated by measuring the haze value by using a haze meter "Haze meter NDH2000" (type name) manufactured by Nippon Denshoku Co., Ltd.

<surface adhesion>

A PET film having an easy-to-treat thickness of 100 μm was attached to one surface of the adhesive film sample to prepare an adhesive sheet, and the width was 20 mm and the length was 12.5 mm. This was wound on a cylindrical rod of 8 mm Φ PP and PC, and laminated on a cylindrical rod by using a cellophane tape. By the above procedure, the adhesive sheet is attached to a state of approximately 50% of the circumference of each cylindrical rod. Next, in a state of being fixed via a cellophane tape, a pressure-bonding treatment at 50 ° C, 0.5 MPa, and 20 minutes was performed in an autoclave. After press-fitting, it was stored at 23 ° C and 50% RH for 1 hour, and the peeled cellophane tape was taken as a sample. The sample was allowed to stand at 23 ° C for 24 hours and at 85 ° C for 24 hours to measure the presence or absence of peeling of the adhesive sheet, and the peeling distance was measured when the adhesive sheet was peeled off, and evaluated according to the criteria shown below.

○: no peeling

△: The distance at which the adhesive sheet peeled off was 1 mm or less.

×: The peeling distance of the adhesive sheet exceeds 1 mm.

Examples 2 to 9 and Comparative Examples 1 to 8

In the first embodiment, the types and ratios of the acrylic adhesive polymer and the vinyl polymer were changed as shown in Table 2 and Table 3 to obtain an adhesive composition, and the same measurement as in Example 1 was carried out. Table 2 and Table 3 The result is displayed in .

Examples 1 to 9 using the adhesive composition of the present invention showed good transparency, and exhibited high adhesion strength to each of the attached bodies in a wide temperature range of 23 ° C to 85 ° C. Moreover, the use of such an adhesive composition to obtain a laminate of PC as a substrate is even After exposure for 24 hours under high temperature and high humidity conditions, no adhesion or peeling of the adhesive sheet was observed, and it was excellent in durability. Furthermore, good results were obtained for the curved surface adhesion of various attached bodies.

Among them, Examples 1 to 5 and 7 to 9 in which the bonding strength to the PC of 15 ° C or higher at 85 ° C was excellent in the evaluation of the durability and the curved surface adhesion of the PC as the attached body. result. Further, Examples 1 to 3, 5, 7, and 8 in which the bonding strength of PP to 5.0 N/25 mm or more at 85 ° C showed good results in the evaluation of all the curved surfaces of PP as the attached body. .

In the experimental examples in which the constituent units of the acrylic adhesive polymer (B) of Comparative Examples 1 to 5 are small (80% by mass) from the alkyl (meth)acrylate, all of the constituent units are not obtained. Durability and surface adhesion are balanced.

Further, in Comparative Examples 6 to 8, although the acrylic adhesive polymer (B) specified in the present invention was used, the segregation of the vinyl polymer (A) was insufficient when the adhesive layer was formed, and almost no visible was observed. The difference between the Tg of the surface layer and the Tg of the entire adhesive. Therefore, the adhesion to various attached bodies is poor, and durability and curved surface adhesion are also insufficient.

[Industrial use possibility]

The adhesive composition of the present invention can be applied to various general adhesive processed articles such as adhesive films, adhesive sheets, adhesive tapes, labels, and the like. Specific examples of the adhesive processed product include an adhesive sheet, an adhesive film, an adhesive tape, a pressure-sensitive adhesive tape, a surface protective film, and surface protection. Tape, masking tape, tape for electrical insulation, laminates, etc.

In addition to the above, the adhesive composition of the present invention is excellent in transparency and heat and humidity resistance, and has high adhesive strength and adhesiveness to various adherends such as glass and plastic, and is also suitable for a touch panel and a liquid crystal display device. A display such as an organic EL display device or a plasma display panel, and a combination of various optical films used therefor.

Claims (9)

An adhesive composition comprising a vinyl polymer (A) having a glass transition temperature (Tg) of 40 ° C or more and 200 ° C or less and a number average molecular weight of 500 to 10,000 and an adhesive of an acrylic adhesive polymer (B) The composition of the present invention is characterized in that the acrylic pressure-sensitive adhesive (B) is a constituent unit derived from a (meth)acrylic acid alkoxyalkyl ester in an amount of 85% by mass or more based on all the constituent units thereof. 100 parts by mass of the acrylic adhesive polymer (B), and the ratio of the vinyl polymer (A) is 0.5 to 30 parts by mass, and the adhesive composition is applied onto a separator to be dried to obtain an adhesive layer. In the case of the adhesive layer, the Tg calculated from the composition of the surface portion obtained by X-ray photoelectron spectroscopy is higher than the Tg of the entire adhesive layer by 30 ° C or more. The adhesive composition according to claim 1, wherein the vinyl polymer (A) has at least one monomer selected from the group consisting of an aliphatic cyclic vinyl compound and an aromatic vinyl compound. Construction unit. An adhesive composition according to claim 1 or 2, wherein an adhesive sheet of an adhesive layer having a film thickness of 50 μm formed of the above-mentioned adhesive composition is provided on a 100 μm thick polyethylene terephthalate film substrate. The polycarbonate sheet at 85 ° C has a bonding strength of 15 N/25 mm or more. The adhesive composition of claim 1 or 2, wherein the 100 μm thick polyethylene terephthalate film substrate is provided with the aforementioned adhesive The adhesive sheet of the adhesive layer having a film thickness of 50 μm formed by the object had a bonding strength of 5.0 N/25 mm or more with respect to the polypropylene plate at 85 °C. A method for producing an adhesive composition, characterized in that it is blended with 100 parts by mass of the acrylic adhesive polymer (B) containing 85 mass% or more of a constituent unit derived from alkoxyalkyl (meth)acrylate. When the glass transition temperature (Tg) of 0.5 parts by mass or more and 30 parts by mass or less is 40° C. or more and 200° C. or less and the number average molecular weight is 500 to 10,000, the adhesive composition is applied to the separator. On the plate, the Tg calculated from the composition of the surface portion obtained by X-ray photoelectron spectroscopy of the obtained adhesive layer is selectively blended in a manner that is higher than the Tg of the entire adhesive layer by 30 ° C or more. The vinyl polymer (A) and the acrylic adhesive polymer (B). An adhesive sheet or an adhesive tape obtained by providing an adhesive layer formed of the adhesive composition according to any one of claims 1 to 4 on one or both sides of a substrate. An adhesive article obtained by laminating a glass plate and/or a transparent plastic plate on one or both sides of an adhesive layer formed of the adhesive composition according to any one of claims 1 to 4. An adhesive article comprising an adhesive product having an adhesive layer comprising a vinyl polymer (A) having a glass transition temperature (Tg) of 40 ° C or more and 200 ° C or less and a number average molecular weight of 500 to 10,000 and acrylic acid The adhesive polymer (B), the acrylic adhesive polymer (B) is relative to the entire structure The unit of the vinyl polymer (A) is contained in an amount of 85% by mass or more of the structural unit derived from the alkoxyalkyl (meth)acrylate, and 100 parts by mass based on 100 parts by mass of the acrylic adhesive polymer (B). The vinyl polymer (A) is contained in a higher concentration in at least one surface layer side opposed to the thickness direction of the pressure-sensitive adhesive layer in an amount of 0.5 parts by mass or more and 30 parts by mass or less. The adhesive article of claim 8, wherein the Tg of the adhesive layer calculated from the composition of the surface portion obtained by X-ray photoelectron spectroscopy is higher than the Tg of the entire adhesive layer by 30 ° C or more.