TWI781299B - Adhesive composition, adhesive sheet, and method for producing acrylic resin containing ethylenically unsaturated group - Google Patents

Abstract

R¹ 係含有乙烯性不飽和基之取代基；R² 係含有選自C、O、N及S中之至少一種之有機基，惟胺甲酸酯基除外；X係O或NH。The present invention provides an adhesive composition that can obtain good adhesive force before active energy ray irradiation and has excellent heat resistance, and has excellent peelability (pollution resistance, micro-adhesion) after active energy ray irradiation even after heating Active energy ray-curable peelable adhesive composition of the adhesive, which contains an acrylic resin containing an ethylenically unsaturated group, and the acrylic resin containing an ethylenically unsaturated group contains the following in the side chain of the acrylic resin The structure part containing ethylenically unsaturated group represented by general formula (1), and the content of ethylenically unsaturated group is 25-500 mmol relative to the acrylic resin containing ethylenically unsaturated group.

R ¹ is a substituent containing an ethylenically unsaturated group; R ² is an organic group containing at least one selected from C, O, N and S, except for a carbamate group; X is O or NH.

Description

Adhesive composition, adhesive sheet and method for producing acrylic resin containing ethylenically unsaturated group

The present invention relates to an adhesive composition containing a specific ethylenically unsaturated group-containing acrylic resin, an adhesive sheet, and a method for producing an ethylenically unsaturated group-containing acrylic resin, especially for metal plates and plastic plates Adhesive sheets for semiconductor fixing such as temporary surface protection, semiconductor wafer dicing steps, etc. are useful adhesive compositions.

Active energy ray-curable resin compositions are known that are cured by irradiating active energy rays such as ultraviolet rays and electron beams, and are used in adhesives, adhesives, paints, printing inks, coating materials, optical molding materials, and the like. In addition, in processing steps such as cutting and drilling of electronic components, in order to prevent contamination and damage of the processed member, the above-mentioned active energy ray curable resin composition is also used as a surface protection agent for temporarily protecting the surface. The adhesive layer of the adhesive sheet is not limited to electronic components in recent years, and some people also use the adhesive sheet for surface protection during the processing of various components.

The above-mentioned adhesive sheet needs to have moderate adhesion to the processed member due to the miniaturization of processing and the thinning of the processed member in recent years. On the other hand, after the function of surface protection is over, there are adhesive sheets for surface protection. The necessity of peeling, when peeling, it needs to be peeled off with light force without residual glue.

The active energy ray-curable resin composition used in the adhesive sheet, for example, is obtained by blending at least one of monomers and oligomers having ethylenically unsaturated groups into the acrylic resin, or by making the acrylic resin itself contain ethylene. Sexual unsaturated groups to exhibit active energy ray hardening properties. Among them, if the acrylic resin itself contains ethylenically unsaturated group-containing acrylic resin, since the acrylic resin itself will form a cross-linked structure after being irradiated with active energy rays, it is considered that the hardened The point of view that the modulus of elasticity is easy to increase and the point of view that non-crosslinked components are not easy to remain in the adherend are advantageous.

As an acrylic resin containing an ethylenically unsaturated group used in an adhesive sheet for temporary surface protection in this way, for example, Patent Document 1 describes an acrylic resin prepared by copolymerizing 2-hydroxyethyl acrylate. The resulting acrylic polymer is urethanized with 2-methacryloxyethyl isocyanate to contain ethylenically unsaturated groups.

In addition, Patent Document 2 describes an adhesive tape for processing electronic components, which uses an acrylic copolymer obtained by copolymerizing methacrylic acid and 2-hydroxyethyl methacrylate for an esterification reaction. Acrylic resin containing ethylenically unsaturated groups.

In addition, in the manufacturing process of electronic components in recent years, there are many cases where the components in the state where the adhesive sheet is attached are exposed to high temperature. Therefore, the adhesive sheet used in the manufacturing process of electronic components also needs to be able to withstand high temperature conditions. heat resistance. [Prior Art Literature] [Patent Document]

[Patent Document 1] Japanese Unexamined Patent Publication No. 2010-53346 [Patent Document 2] Japanese Patent Laid-Open No. 2016-121231

[Problem to be Solved by the Invention]

However, in the technique disclosed in Patent Document 1 above, the exfoliation property after active energy ray irradiation at normal temperature is good, but when exfoliation is performed by applying active energy ray irradiation after exposing to a high temperature condition of 150° C. In acrylic resin, the urethane bond, which is the bonding part of the ethylenically unsaturated group, is easily decomposed by heat, so even if the active energy ray is applied, the adhesive force is difficult to decrease, and it is easy to leave residues on the adherend when peeling off. glue. Therefore, further improvement in heat resistance is required.

Also, in the technique disclosed in the above-mentioned Patent Document 2, although an ethylenically unsaturated group is introduced through an ester bond, since the main chain part of the introduced unsaturated group is derived from the structure of methacrylic acid, the main chain is easily decomposed by heat. Reaction and heat resistance are still poor, and further improvement is required.

Here, the present invention is based on such a background, and provides an active energy ray-curable peel-off adhesive composition, which can obtain good adhesive force before irradiating active energy ray, and has excellent heat resistance. Adhesive with excellent peelability (pollution resistance, micro-adhesion) even after energy rays. [Means to solve the problem]

Therefore, the present inventors have found that by using an acrylic resin containing a specific amount of ethylenically unsaturated groups of a specific structure, it is possible to obtain an adhesive having good adhesion before active energy ray irradiation and excellent heat resistance, and Adhesive composition of an adhesive that is also excellent in peelability (pollution resistance, microadhesiveness) after active energy ray irradiation after heating.

Also, the present inventors found that by reacting a hydroxyl-containing acrylic resin (α) with an ethylenically unsaturated group-containing carboxylic acid (β) in the presence of a compound (I) represented by the general formula (2), There is no urethane bond, and an ethylenically unsaturated group can be added to the acrylic resin with high yield even at low temperature.

That is, the first gist of the present invention is an adhesive composition comprising: an acrylic resin containing an ethylenically unsaturated group; the acrylic resin containing an ethylenically unsaturated group contains the following general The structure part containing ethylenically unsaturated group represented by formula (1), and the content of ethylenically unsaturated group is 25-500mmol/100g relative to the acrylic resin containing ethylenically unsaturated group.

R¹ 係含有乙烯性不飽和基之取代基，R² 係含有選自C、O、N及S中至少一種之有機基(惟，胺甲酸酯基除外)，X係O或NH。[chemical 1]

R1 is ^a substituent containing an ethylenically unsaturated group, R2 is an organic group containing at least one of C, O, N and S ⁽ except for a carbamate group), and X is O or NH.

Moreover, the 2nd aspect of this invention is an adhesive sheet which has the adhesive agent layer which crosslinked the adhesive agent composition of the said 1st aspect.

Furthermore, the third gist of the present invention is a method for producing an ethylenically unsaturated group-containing acrylic resin, which is characterized in that: a hydroxyl-containing acrylic resin (α) and an ethylenically unsaturated group-containing carboxylic acid (β ) react in the presence of the compound (I) represented by the following general formula (2).

此處，R³ 及R⁴ 係表示碳數1～20之烴基。 [發明之效果][Chem 2]

Here, R ³ and R ⁴ represent a hydrocarbon group having 1 to 20 carbon atoms. [Effect of Invention]

The adhesive composition of the present invention contains an acrylic resin containing an ethylenically unsaturated group, and the acrylic resin containing an ethylenically unsaturated group contains an ethylenically unsaturated group represented by the following general formula (1) in the side chain of the acrylic resin. The structural part of the saturated group, and the content of the ethylenically unsaturated group is 25-500mmol/100g relative to the acrylic resin containing the ethylenically unsaturated group. Therefore, since the adhesive sheet having the adhesive layer formed by crosslinking the adhesive composition contains an acrylic resin having a predetermined amount of a specific ethylenically unsaturated group-containing structural site in the side chain, before irradiating active energy rays Excellent adhesion and peelability after irradiation with active energy rays. In addition, the above-mentioned adhesive composition and adhesive sheet have excellent heat resistance because the above-mentioned structural part containing an ethylenically unsaturated group does not have a urethane group, and even after heating at a high temperature, the peelability after irradiation with active energy rays remains. Excellent.

R¹ 係含有乙烯性不飽和基之取代基，R² 係含有選自C、O、N及S中至少一種之有機基(惟，胺甲酸酯基除外)，X係O或NH。[Chem 3]

R1 is ^a substituent containing an ethylenically unsaturated group, R2 is an organic group containing at least one of C, O, N and S ⁽ except for a carbamate group), and X is O or NH.

Moreover, in the present invention, especially when the above-mentioned ethylenically unsaturated group-containing acrylic resin contains a hydroxyl group, the adhesive force before irradiation with active energy rays is more excellent.

In addition, if the adhesive composition of the present invention contains a crosslinking agent, the adhesive force before irradiation with active energy rays will be more excellent.

In addition, if the adhesive composition of the present invention contains a photopolymerization initiator, the curability of the acrylic resin containing an ethylenically unsaturated group can be improved by irradiation of active energy rays, and the peelability after irradiation of active energy rays can be improved. more excellent.

Also, in the present invention, especially the above-mentioned ethylenically unsaturated group-containing acrylic resin is a combination of the hydroxyl-containing acrylic resin (α) and the ethylenically unsaturated group-containing carboxylic acid (β) in the aforementioned general formula (2 ) in the presence of the compound (I) represented by the reaction, the ethylenically unsaturated group-containing acrylic resin can be obtained in high yield. Therefore, the adhesive force before active energy ray irradiation and the detachability after active energy ray irradiation are more excellent, and the heat resistance is excellent, and the detachability after active energy ray irradiation is also excellent even after heating at a high temperature.

In addition, in the present invention, especially if the above-mentioned ethylenically unsaturated group-containing acrylic resin is obtained by esterifying a hydroxyl-containing acrylic resin (α) and (meth)acrylic anhydride (γ), Then, the acrylic resin containing ethylenically unsaturated groups can be obtained in high yield. Therefore, the adhesive force before active energy ray irradiation and the releasability after active energy ray irradiation are more excellent, and the heat resistance is excellent, and the releasability after active energy ray irradiation is also excellent even after heating at a high temperature.

Also, according to the production method of the present invention, the acrylic resin (α) containing a hydroxyl group and the carboxylic acid (β) containing an ethylenically unsaturated group are carried out in the presence of the compound (I) represented by the aforementioned general formula (2). reaction, so acrylic resins containing ethylenically unsaturated groups can be obtained in high yield. In addition, this production method does not require complicated operations for removing by-products after the reaction, and an ethylenically unsaturated group-containing acrylic resin suitable for applications exposed to high temperatures can be obtained.

In addition, in the production method of the present invention, the above-mentioned acrylic resin (α) containing a hydroxyl group and the carboxylic acid (β) containing an ethylenically unsaturated group are combined in the compound (I) represented by the above-mentioned general formula (2). When the reaction is performed in the presence of one or more magnesium compounds and one or more alkali metal compounds, the ethylenically unsaturated group-containing acrylic resin can be obtained in higher yield.

In addition, in the production method of the present invention, especially when the alkali metal constituting the alkali metal compound is lithium, an ethylenically unsaturated group-containing acrylic resin can be obtained with a higher yield.

And, in the production method of the present invention, especially if the compound (I) represented by the aforementioned general formula (2) is di-tertiary butyl dicarbonate, the acrylic acid containing ethylenically unsaturated group can be obtained with a higher yield. resin.

In addition, in the production method of the present invention, in particular, in the presence of 0.001 to 1000 mol% of the aforementioned magnesium compound and 0.001 to 1000 mol% of the aforementioned alkali metal compound relative to the aforementioned ethylenically unsaturated group-containing carboxylic acid (β) When the reaction is carried out, an ethylenically unsaturated group-containing acrylic resin can be obtained with a higher yield.

In addition, in the production method of the present invention, when the content of the hydroxyl group-containing monomer (a1) constituting the above-mentioned hydroxyl group-containing acrylic resin (α) is 0.1 to 50% by mass relative to the entire polymerized components, the When the acrylic resin containing ethylenically unsaturated groups is used as an adhesive, it can be hardened by irradiating active energy rays, and can have better peelability.

In addition, in the production method of the present invention, especially if the ethylenically unsaturated group content of the ethylenically unsaturated group-containing acrylic resin is 25 to 500 mmol/100 g relative to the ethylenically unsaturated group-containing acrylic resin , when the obtained acrylic resin containing ethylenically unsaturated groups is used as an adhesive, it can be hardened by irradiating active energy rays, and can have better peelability.

In addition, in the production method of the present invention, especially if the acid value of the above-mentioned hydroxyl group-containing acrylic resin (α) is 10 mgKOH/g or less, gelation will not occur during the reaction, and it can be obtained efficiently with a higher yield. Acrylic resin containing ethylenically unsaturated groups.

Hereinafter, although the form required for carrying out this invention is demonstrated concretely, this invention is not limited to these. In the present invention, "(meth)acrylic acid" refers to acrylic acid or methacrylic acid, "(meth)acryl" refers to acryl or methacryl, and "(meth)acrylate" refers to Acrylate or methacrylate. In addition, the "acrylic resin" refers to a resin obtained by polymerizing a (meth)acrylate-based monomer polymerization component containing at least one kind. In addition, in the present invention, the term "sheet" is not particularly different from "film" and "tape", and is described as including them.

The adhesive composition of the present invention is usually based on the premise that it will be peeled off after bonding with metal plates, plastic plates, semiconductor wafers and other processed components, and is mainly used in the adhesive layer of the adhesive sheet. The above-mentioned adhesive sheet is formed by coating the adhesive composition on the substrate sheet to form an adhesive layer, and after bonding to the workpiece, the adhesive layer is hardened and the adhesive force is reduced by irradiating active energy rays, so that it can be easily removed from the workpiece. Processing member stripping.

The adhesive composition of the present invention contains an acrylic resin containing an ethylenically unsaturated group-containing structural site represented by the following general formula (1) in a predetermined amount.

R¹ 係含有乙烯性不飽和基之取代基，R² 係含有選自C、O、N及S中至少一種之有機基(惟，胺甲酸酯基除外)，X係O或NH。[chemical 4]

R1 is ^a substituent containing an ethylenically unsaturated group, R2 is an organic group containing at least one of C, O, N and S ⁽ except for a carbamate group), and X is O or NH.

The acrylic resin containing the ethylenically unsaturated group structure represented by the above-mentioned general formula (1) is obtained by combining the hydroxyl-containing acrylic resin (α) and the ethylenically unsaturated group-containing carboxylic acid (β) in the compound (I ) in the presence of the reaction, or a hydroxyl-containing acrylic resin (α) and (meth)acrylic anhydride (γ) are obtained by the reaction. These components will be described below.

[Hydroxyl-containing acrylic resin (α)] The above-mentioned acrylic resin (α) containing a hydroxyl group is a monomer (a1) containing a hydroxyl group, an alkyl (meth)acrylate (a2), preferably a monomer (a3) containing a functional group (but not including a monomer containing a hydroxyl group) monomer (a1)) and, if necessary, other copolymerizable monomers (a4) can be obtained by polymerizing.

The hydroxyl group contained in the above-mentioned hydroxyl group-containing monomer (a1) will form an ethylenically unsaturated group-containing carboxylic acid (β) or (meth)acrylic anhydride (meth)acrylic anhydride ( γ) reaction point. In addition, the hydroxyl group also becomes a reaction point with the crosslinking agent described later, and contains more than the amount that will be consumed in the reaction with the ethylenically unsaturated group-containing carboxylic acid (β) or (meth)acrylic anhydride (γ). Content is better.

The aforementioned hydroxy group-containing monomer (a1) does not include methacrylate-based monomers in consideration of heat resistance, and examples include hydroxy-containing acrylate-based monomers or hydroxy-acrylamide-based monomers. As for the above-mentioned hydroxyacrylate-containing monomers or hydroxyacrylamide-containing monomers, specific examples include 2-hydroxyethyl acrylate, 4-hydroxybutyl acrylate, and 5-hydroxypentyl acrylate. , 6-hydroxyhexyl acrylate, 8-hydroxyoctyl acrylate, etc. Lactone-modified monomers, diethylene glycol acrylate, polyethylene glycol acrylate and other oxyalkylene-modified monomers, 2-acryloxyethyl-2-hydroxyethylphthalic acid, etc. contain Monomers with primary hydroxyl groups; 2-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, 3-chloro-2-hydroxypropyl acrylate and other monomers containing secondary hydroxyl groups; 2,2-dimethyl - 2-Hydroxyethyl acrylate and other monomers containing tertiary hydroxyl groups. These can be used individually or in combination of 2 or more types. Among the above-mentioned hydroxyl group-containing monomers (a1), those containing a primary hydroxyl group are preferable from the viewpoint of excellent reactivity with ethylenically unsaturated group-containing carboxylic acid (β) or (meth)acrylic anhydride (γ) described later. The monomer is particularly preferably 2-hydroxyethyl acrylate and 4-hydroxybutyl acrylate.

The content of the hydroxyl group-containing monomer (a1) is usually 0.1 to 50% by weight, preferably 5 to 40% by weight, more preferably 10 to 35% by weight, based on the total polymerized components of the hydroxyl group-containing acrylic resin (α). weight%. If the content is too large, crosslinking will proceed before the drying step, and problems with coating properties will tend to occur. If the content is too small, it will not be possible to combine with ethylenically unsaturated group-containing carboxylic acid (β) or (methyl) in sufficient content. Acrylic anhydride (γ) reacts and tends to lower the detachability after active energy ray irradiation.

The above-mentioned alkyl (meth)acrylate (a2) is the main component of the polymerization component to obtain the hydroxyl group-containing acrylic resin (α). In addition, in the above-mentioned alkyl (meth)acrylate (a2), the carbon number of the alkyl group is usually 1-24, preferably 1-20, especially preferably 1-12, and more preferably 1-8. If the carbon number is too large, the polymerizability will be low, and it will tend to remain as unreacted monomer in the hydroxyl group-containing acrylic resin (α), and tend to cause contamination and adhesive residue on workpieces.

Specific examples of the above-mentioned alkyl (meth)acrylate (a2) include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, (meth) Isobutyl acrylate, tertiary butyl (meth)acrylate, n-propyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-(meth)acrylate Octyl, isooctyl (meth)acrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, (meth)acrylate aliphatic alkyl (meth)acrylates such as isostearyl acrylate; alicyclic alkyl (meth)acrylates such as cyclohexyl (meth)acrylate and isocamphoryl (meth)acrylate, etc. . These may be used alone or in combination of two or more. Among the above-mentioned alkyl (meth)acrylates (a2), methyl (meth)acrylate, n-(meth)acrylic acid, etc. Butyl ester, 2-ethylhexyl (meth)acrylate.

Furthermore, the content of the above-mentioned alkyl (meth)acrylate (a2) is usually 30 to 99% by weight, preferably 40 to 95% by weight, and particularly preferably It is 50 to 90% by weight. When the content is too small, the adhesive force before active energy ray irradiation tends to decrease easily, and when too much, the adhesive force before active energy ray irradiation tends to become too high.

In the present invention, it is preferable to contain a hydroxyl group in the acrylic resin from the viewpoint of excellent reaction with the crosslinking agent described later, and it is preferable to contain a monomer containing a functional group that reacts with the crosslinking agent described below in addition to the monomer (a1) containing a hydroxyl group. (a3) as a polymerization component.

The above-mentioned functional group-containing monomer (a3) includes, for example, carboxyl group-containing monomers, amine group-containing monomers, amido group-containing monomers, glycidyl group-containing monomers, sulfonic acid-containing Monomers with acetyl groups, monomers with acetyl acetyl groups, etc. Moreover, these functional group containing monomers can be used individually or in combination of 2 or more types.

As for the above carboxyl group-containing monomers, for example, (meth)acrylic acid, (meth)acrylic acid dimer, crotonic acid, maleic acid, maleic anhydride, fumaric acid, citraconic acid, valeric acid, Acrylic acid, methylene succinic acid, acrylamide N-glycolic acid, cinnamic acid, etc. Among them, (meth)acrylic acid is preferably used from the viewpoint of copolymerizability.

The content of the carboxyl group-containing monomer is usually at most 1% by weight, preferably at most 0.5% by weight, more preferably at most 0.3% by weight, based on the total polymerized components of the hydroxyl group-containing acrylic resin (α). If the content is too large, the processed member tends to deteriorate easily, crosslinking proceeds before the drying step, and problems with coatability tend to occur easily.

The monomers containing amino groups mentioned above include, for example, N,N-dimethylaminoethyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylate, and the like.

The content of the amino group-containing monomer is usually 10% by weight or less, preferably 5% by weight or less, more preferably 2% by weight or less, based on the total polymerized components of the hydroxyl group-containing acrylic resin (α). When this content is too large, crosslinking will progress before a drying process, and there exists a tendency for applicability to generate|occur|produce a problem easily.

啉、二甲基(甲基)丙烯醯胺、二乙基(甲基)丙烯醯胺、二甲基胺基丙基丙烯醯胺、(甲基)丙烯醯胺、N-羥甲基(甲基)丙烯醯胺等(甲基)丙烯醯胺系單體等。For the monomers containing amide groups mentioned above, for example, ethoxymethyl (meth)acrylamide, n-butoxymethyl (meth)acrylamide, (meth)acrylamide

phenoline, dimethyl(meth)acrylamide, diethyl(meth)acrylamide, dimethylaminopropylacrylamide, (meth)acrylamide, N-methylol(meth)acrylamide (meth)acrylamide-based monomers such as base) acrylamide and the like.

The content of the amide group-containing monomer is usually 30% by weight or less, preferably 25% by weight or less, more preferably 20% by weight or less, based on the total polymerized components of the hydroxyl group-containing acrylic resin (α). When this content is too large, crosslinking will progress before a drying process, and there exists a tendency for applicability to generate|occur|produce a problem easily.

Examples of the glycidyl group-containing monomer include glycidyl methacrylate, allylglycidyl methacrylate, and the like.

The content of the glycidyl group-containing monomer is usually 20% by weight or less, preferably 15% by weight or less, more preferably 10% by weight or less, based on the entire polymerized components of the hydroxyl group-containing acrylic resin (α). When this content is too large, crosslinking will progress before a drying process, and there exists a tendency for applicability to generate|occur|produce a problem easily.

Examples of monomers containing sulfonic acid groups include olefin sulfonic acids such as vinylsulfonic acid, allylsulfonic acid, and methallylsulfonic acid; 2-acrylamide-2-methylolpropane Sulfonic acid, styrylsulfonic acid or its salt, etc.

The content of the above-mentioned sulfonic acid group-containing monomer is usually at most 1% by weight, preferably at most 0.5% by weight, more preferably at most 0.3% by weight, based on the entire polymerized components of the hydroxyl group-containing acrylic resin (α). When this content is too large, crosslinking will progress before a drying process, and there exists a tendency for applicability to generate|occur|produce a problem easily.

Examples of the acetoacetyl group-containing monomer include 2-(acetylacetyloxy)ethyl (meth)acrylate, allyl acetylacetate, and the like.

The content of the acetoacetyl group-containing monomer is usually not more than 10% by weight, preferably not more than 5% by weight, more preferably not more than 1% by weight, based on the total polymerized components of the hydroxyl group-containing acrylic resin (α). . When this content is too large, crosslinking will progress before a drying process, and there exists a tendency for applicability to generate|occur|produce a problem easily.

Examples of other copolymerizable monomers (a4) include vinyl carboxylate monomers such as vinyl acetate, vinyl propionate, vinyl stearate, and vinyl benzoate; (meth)acrylic acid Phenyl ester, benzyl (meth)acrylate, phenoxyethyl (meth)acrylate, phenylethylene glycol (meth)acrylate, 2-hydroxy-3-phenoxy (meth)acrylate Monomers containing aromatic rings such as propyl ester, styrene, α-toluene, etc.; (meth)acrylate monomers containing biphenoxy structure such as biphenoxyethyl (meth)acrylate; ) 2-methoxyethyl acrylate, 2-ethoxyethyl (meth)acrylate, methoxydiethylene glycol (meth)acrylate, ethoxydiethylene glycol (meth)acrylate , methoxypolyethylene glycol (meth)acrylate, polypropylene glycol mono(meth)acrylate and other monomers containing alkoxy or oxyalkyl groups; acrylonitrile, methacrylonitrile, vinyl chloride , Vinylene Chloride, Alkyl Vinyl Ether, Vinyl Toluene, Vinyl Pyridine, Vinyl Pyrrolone, Dialkyl Iconate, Dialkyl Fumarate, Allyl Alcohol, Acryl Chlorine, methyl vinyl ketone, allyl trimethyl ammonium chloride, dimethyl allyl vinyl ketone, etc. These may be used alone or in combination of two or more.

The content of the aforementioned other copolymerizable monomer (a4) is usually not more than 40% by weight, preferably not more than 30% by weight, more preferably not more than 25% by weight, based on the total polymerized components of the hydroxyl group-containing acrylic resin (α). . When there are too many other copolymerizable monomers (a4), the adhesive property tends to fall easily.

The hydroxyl-containing acrylic resin (α) used in the present invention is obtained by combining the hydroxyl-containing monomer (a1), (meth)acrylic acid alkyl ester (a2), preferably the functional group-containing monomer (a3) , It can be obtained by polymerizing other copolymerizable monomer (a4) as a polymerization component as needed. Usually, this polymerization method can be suitably performed by conventionally known methods, such as solution radical polymerization, suspension polymerization, block polymerization, and emulsion polymerization. Among them, production by solution radical polymerization is ideal in view of safety, stability, and the production of hydroxyl-containing acrylic resin (α) with an arbitrary monomer composition.

The radical polymerization of the above solution, for example, mixing or dropping hydroxyl-containing monomers (a1), (meth)acrylic acid alkyl esters (a2), functional group-containing monomers (a3), and other copolymerizable monomers in an organic solvent monomer components such as the body (a4) and a polymerization initiator, and polymerize in a reflux state or usually at 50 to 98° C. for 0.1 to 20 hours.

Examples of organic solvents used in the above polymerization reaction include aromatic hydrocarbons such as toluene and xylene, aliphatic hydrocarbons such as hexane, esters such as ethyl acetate and butyl acetate, n-propanol, isopropyl alcohol, and the like. Aliphatic alcohols such as alcohol, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.

As the above-mentioned polymerization initiator, a general radical polymerization initiator can be used, specifically, azo-based polymerization initiators such as azobisisobutyronitrile and azobisdimethylvaleronitrile, benzene peroxide, etc. Peroxide-based polymerization initiators such as formyl, lauryl peroxide, di-tert-butyl peroxide, cumene hydroperoxide, etc.

The hydroxyl-containing acrylic resin (α) obtained by the above-mentioned polymerization method is usually obtained in the state of a solution. The viscosity at 25°C of the above hydroxyl-containing acrylic resin (α) solution is preferably 5-50,000 mPa･s, more preferably 10-20,000 mPa･s. If the viscosity is out of the above range, the reaction will be delayed when the hydroxyl-containing acrylic resin (α) is reacted with the ethylenically unsaturated carboxylic acid compound (β) or (meth)acrylic anhydride (γ). When the obtained ethylenically unsaturated group-containing acrylic resin is used as an adhesive, the applicability tends to decrease. In addition, the measuring method of the viscosity uses an E-type viscometer.

The weight average molecular weight of the hydroxyl group-containing acrylic resin (α) is usually 100,000 to 2 million, preferably 150,000 to 1.5 million, particularly preferably 200,000 to 1.2 million, and more preferably 300,000 to 1 million. If the weight average molecular weight is too small, the staining property on the workpiece tends to increase, and if it is too large, the coating property tends to decrease or become disadvantageous in terms of cost.

In addition, the degree of dispersion (weight average molecular weight/number average molecular weight) of the hydroxyl group-containing acrylic resin (α) is preferably 20 or less, more preferably 10 or less, more preferably 7 or less, still more preferably 5 or less. If the degree of dispersion is too high, there is a tendency for the contamination of the workpiece to be processed to increase. In addition, the lower limit of the degree of dispersion is usually preferably 1.1 in consideration of production constraints.

The above-mentioned weight average molecular weight is the weight average molecular weight obtained by converting the standard polystyrene molecular weight through high-speed liquid chromatography (manufactured by Japan Waters Corporation, "Waters 2695 (body)" and "Waters 2414 (detector)") , 3 columns: Shodex GPC KF-806L (exclusion limit molecular weight: 2×10 ⁷ , separation range: 100～2×10 ⁷ , number of theoretical plates: 10,000 laminates/root, filler material: styrene-two Vinylbenzene copolymer, filler particle size: 10 μm) are used in series to measure, and the number average molecular weight can also be obtained using the same method.

In addition, the glass transition temperature (Tg) of the hydroxyl-containing acrylic resin (α) is usually below 40°C, preferably -70 to 20°C, particularly preferably -65 to 0°C, and more preferably -60 to -10°C. ℃. If the glass transition temperature is too high, the adhesion tends to decrease, and if it is too low, the contamination to the processed components tends to increase.

The above-mentioned glass transition temperature (Tg) is a value calculated by substituting the glass transition temperature and weight fraction of the respective monomers constituting the hydroxyl group-containing acrylic resin (α) as homopolymers by substituting the following Fox's formula.

Tg：含有羥基之丙烯酸系樹脂(α)之玻璃轉移溫度(K) Tga：單體A之同元聚合物之玻璃轉移溫度(K) Wa：單體A之重量分率 Tgb：單體B之同元聚合物之玻璃轉移溫度(K) Wb：單體B之重量分率 Tgn：單體N之同元聚合物之玻璃轉移溫度(K) Wn：單體N之重量分率 (Wa+Wb+…+Wn=1)[number 1]

Tg: glass transition temperature (K) of acrylic resin (α) containing hydroxyl group Tga: glass transition temperature (K) of homopolymer of monomer A Wa: weight fraction of monomer A Tgb: weight fraction of monomer B Glass transition temperature (K) of homopolymer Wb: weight fraction of monomer B Tgn: glass transition temperature (K) of homopolymer of monomer N Wn: weight fraction of monomer N (Wa+Wb+ …+Wn=1)

Here, the glass transition temperature when the monomer constituting the hydroxyl-containing acrylic resin (α) is made into a homopolymer is usually measured by a differential scanning calorimeter (DSC), which can be based on JIS K 7121-1987 , JIS K 6240 method for determination.

Also, the acid value of the hydroxyl-containing acrylic resin (α) is preferably not more than 10 mgKOH/g, more preferably not more than 5 mgKOH/g, more preferably not more than 2 mgKOH/g, and more preferably not more than 1 mgKOH/g. If it exceeds the above range, gelation tends to occur during production.

The acid value of the above-mentioned hydroxyl group-containing acrylic resin (α) can be obtained in the following manner. That is, the hydroxyl-containing acrylic resin (α) of the solid content Z weight % of Yg was sampled in a beaker, and dissolved in a mixed solvent of toluene:methanol=7:3 (weight ratio). After dissolving, add an appropriate amount of phenolphthalein, stir with a stirrer, and titrate with potassium hydroxide (KOH) solution. The amount of KOH solution X mL when the solution becomes light pink is used as the end point, and the acid value is calculated according to the following formula 1. In addition, 0.1mol/L KOH solution is usually used. In the case of acrylic resin (α) containing hydroxyl groups with low acid value, 0.01mol/L KOH solution can also be used in order to improve the accuracy. [Formula 1] Acid value (mgKOH/g)=X×(f×M×56.11)/(Y×Z/100) ・f: factor of KOH solution ・M: Molar concentration of KOH solution (mol/L) ・X: Amount of KOH solution (mL) ・Y: Sampling amount of acrylic resin containing hydroxyl group (g) ・Z: Solid content of hydroxyl-containing acrylic resin (% by weight)

[Ethylenically unsaturated group-containing carboxylic acid (β)] In the present invention, the ethylenically unsaturated group-containing carboxylic acid (β) used together with the above-mentioned hydroxyl-containing acrylic resin (α) can be expressed as "R ⁵ -COOH", R ⁵ is a substituent having an ethylenically unsaturated group. Specific examples of ethylenically unsaturated group-containing carboxylic acid (β) include (meth)acrylic acid, β-carboxyethyl (meth)acrylate, (meth)acrylic acid dimer, crotonic acid , maleic acid, maleic anhydride, fumaric acid, citraconic acid, glutaconic acid, methylene succinic acid, acrylamide N-glycolic acid, cinnamic acid, etc. Among them, (meth)acrylic acid and β-carboxyethyl (meth)acrylate are preferable from the viewpoint of reactivity. These may be used individually or in combination of 2 or more types.

[Compound (I)] In the present invention, as the compound (I) used together with the aforementioned hydroxyl group-containing acrylic resin (α) and the aforementioned ethylenically unsaturated group-containing carboxylic acid (β), compounds represented by the following general formula (2) can be used: compound. Also, the compound (I) represented by the following general formula (2) will generate an intermediate containing components derived from the compound according to the reaction, but the finally obtained acrylic resin containing ethylenically unsaturated groups does not contain compounds derived from the compound ( I) The ingredients of origin.

此處，R³ 及R⁴ 係表示碳數1～20之烴基。[chemical 5]

Here, R ³ and R ⁴ represent a hydrocarbon group having 1 to 20 carbon atoms.

In the compound represented by the above general formula (2), R ³ and R ⁴ each represent a hydrocarbon group. In addition, the carbon number of the above-mentioned hydrocarbon group is 1-20, preferably 2-10, particularly preferably 3-7, in view of the ease of acquisition.

In the above-mentioned general formula (2), R ³ and R ⁴ are not limited in type and structure as long as they are hydrocarbon groups. Specific examples of the above-mentioned hydrocarbon groups include alkyl groups, alkenyl groups, and alkynyl groups. These may also be any of linear, branched, and cyclic structures. Moreover, an aryl group is also mentioned as said hydrocarbon group. ^In addition, these hydrocarbon groups may also contain ether bonds in their structures, or ^R3 and R4 may be bonded to form a ring structure.

For the compound (I) represented by the above-mentioned general formula (2), specific examples include diallyl dicarbonate, di-tertiary butyl dicarbonate, di-tertiary pentyl dicarbonate, and dibenzyl dicarbonate. Wait. Among them, since the acrylic resin containing ethylenically unsaturated groups can be produced efficiently, ^R3 and R4 are preferably di ^- tert-butyl dicarbonate of tert-butyl group.

As the compound (I) represented by the above-mentioned general formula (2), a commercial item may be used, or a compound obtained by a known method or the like may be used. Moreover, compound (I) may be used individually, and may use 2 or more types together.

[(Meth)acrylic anhydride (γ)] The (meth)acrylic anhydride (γ) used in the present invention is a compound represented by the following general formula (3).

R⁶ 係氫或甲基。[chemical 6]

R ⁶ is hydrogen or methyl.

[Manufacturing method of acrylic resin containing ethylenically unsaturated group] The acrylic resins containing ethylenically unsaturated groups used in the present invention can be produced by the following methods: (i) A method of reacting a hydroxyl-containing acrylic resin (α) with an ethylenically unsaturated group-containing carboxylic acid (β) in the presence of the compound (I) represented by the aforementioned general formula (2); (ii) A method of esterifying a hydroxyl group-containing acrylic resin (α) and (meth)acrylic anhydride (γ). Among them, the viewpoint of considering the reaction efficiency is preferably the production method of (i) above.

In addition, in each of the above-mentioned production methods, it is preferable to carry out the reaction in the presence of a catalyst described later from the viewpoint of reaction efficiency. Here, the so-called "in the presence of a catalyst" is sufficient as long as the catalyst exists in at least a part of the reaction process, and does not need to always exist in all the stages of the reaction process. In each of the above production methods, as long as a catalyst is added to the reaction system, the requirement of "the presence of a catalyst" is satisfied. For example, after the catalyst is added to the reaction system, even if there is any change in the catalyst during the reaction process, the requirement of "the presence of the catalyst" is satisfied.

The form of the reaction container used for each reaction of said (i) and (ii) is not specifically limited. Also, the raw materials used in the reaction [the case of the above (i) is the acrylic resin (α) containing a hydroxyl group, the carboxylic acid (β) and the compound (I) containing an ethylenically unsaturated group, and the case of the above (ii) is Hydroxyl-containing acrylic resin (α) and (meth)acrylic anhydride (γ)], the method of introducing the catalyst, etc. into the reaction container is not particularly limited, for example, all the raw materials, catalyst, etc. are introduced into the reactor at once. The method of the reaction vessel, the method of introducing part or all of the raw materials and catalysts into the reaction vessel step by step, the method of continuously introducing part or all of the raw materials and catalysts into the reaction vessel, etc. Also, these methods may be combined. Each manufacturing method will be described in detail below.

[Manufacturing method of (i)] The reaction conditions in the production method of (i) above are not particularly limited, and the reaction conditions may be appropriately changed during the reaction.

The amount of the ethylenically unsaturated group-containing carboxylic acid (β) used in the production method of the above (i) is based on a total of 100 mol% of the hydroxyl-containing monomer (a1) in the hydroxyl-containing acrylic resin (α) , the ethylenically unsaturated group-containing carboxylic acid (β) is usually 10-100 mol%, preferably 15-95 mol%, especially preferably 20-90 mol%. If the amount of ethylenically unsaturated group-containing carboxylic acid (β) used is too small, the yield of ethylenically unsaturated group-containing acrylic resin tends to decrease, and ethylenically unsaturated group-containing carboxylic acid (β) If the amount used is too much, the load in the treatment steps after the reaction tends to increase, which is not economical.

Also, the amount of the above-mentioned ethylenically unsaturated group-containing carboxylic acid (β) used is generally 10 to 1000 mol% relative to 100mol% of the compound (I), preferably 10 to 1000mol%. 20-500mol%, especially preferably 50-200mol%. If the amount of ethylenically unsaturated group-containing carboxylic acid (β) used is too small, the yield of ethylenically unsaturated group-containing acrylic resin tends to decrease, and ethylenically unsaturated group-containing carboxylic acid (β) If the amount used is too much, the load tends to increase in the subsequent treatment steps after the reaction, which is not in line with economic benefits.

The reaction temperature is not particularly limited, and the production method of (i) can perform the reaction at a relatively low temperature. The reaction temperature is usually 0 to 180°C, preferably 20 to 100°C, particularly preferably 40 to 70°C. If the reaction temperature is too low, the reaction efficiency tends to decrease, and if the reaction temperature is too high, the by-products tend to increase, or the acrylic resin containing ethylenically unsaturated groups tends to be colored.

Also, the reaction time is not particularly limited, and is usually 0.5 to 72 hours, preferably 2 to 48 hours. If the reaction time is too short, the reaction tends not to proceed sufficiently, and if the reaction time is too long, the improvement in yield tends not to be observed, which is not economical.

In addition, in the production method of (i), the ambient gas and pressure during the reaction are not particularly limited.

In addition, in the production method of (i), when reacting the hydroxyl-containing acrylic resin (α) and the ethylenically unsaturated group-containing carboxylic acid (β) in the presence of the compound (I), it is preferable to contain at least one Magnesium compound and more than one alkali metal compound are used as catalysts. If the reaction is carried out in the presence of the above-mentioned catalyst, the acrylic resin containing ethylenically unsaturated groups can be obtained with a higher yield.

[magnesium compound] As far as magnesium compounds are concerned, examples of magnesium are: oxides, hydroxide salts, carbonates, bicarbonates, silicates, sulfates, ammonium sulfates, nitrates, phosphates, hydrogen phosphates, ammonium phosphates Salts of salts, borates, halides, peroxohalides, hydrogen halides, etc., and inorganic acids; salts of carboxylates, peroxycarboxylates, sulfonates, etc., and organic acids; , hexafluoroacetylacetonate, porphyrin salt, phthalocyanine salt, cyclopentadiene salt, etc. These magnesium salts may be either hydrates or anhydrides. Among them, those of magnesium are more preferable: oxides, hydroxide salts, carbonates, sulfates, ammonium sulfates, nitrates, hydrogen halides, carboxylates, and zirconium salts.

The above-mentioned magnesium compounds include, in more detail, magnesium oxide, magnesium hydroxide, magnesium bicarbonate (alias: basic magnesium carbonate), magnesium sulfate, magnesium ammonium sulfate, magnesium nitrate, magnesium chloride, and magnesium bromide. , Magnesium acetate, Magnesium benzoate, Magnesium (meth)acrylate, Magnesium acetylacetonate. Among them, magnesium hydroxide is preferred.

As these magnesium compounds, commercially available ones may be used, and those produced by known methods or the like may be used. Moreover, a magnesium compound may be used individually or in combination of 2 or more types.

The amount of the magnesium compound used is not particularly limited as long as it can produce an ethylenically unsaturated group-containing acrylic resin, but it is usually 0.001 to 1000 mol% relative to the ethylenically unsaturated group-containing carboxylic acid (β), preferably 0.005% by mole. ~500mol%, especially preferably 0.01~250mol%. If the amount of the magnesium compound used is too small, it tends to be difficult to obtain the effect of further improving the yield of the acrylic resin containing an ethylenically unsaturated group. If the amount of the magnesium compound used is too large, the yield tends not to be further improved. , not in line with economic benefits.

[alkali metal compound] As far as the above-mentioned alkali metal compounds are concerned, examples of alkali metals include: hydride salts, oxides, hydroxide salts, carbonates, bicarbonates, sulfates, nitrates, phosphates, borates, halides, peroxides, etc. Salts of oxyhalides, hydrogen halides, thiocyanates, etc. and inorganic acids; salts of alkoxides, carboxylates, sulfonates, etc., and organic acids; Base salts; acetylacetonate, hexafluoroacetylacetonate, porphyrin salts, phthalocyanine salts, cyclopentadiene salts, etc. These alkali metal salts may be either hydrates or anhydrides. Among them, alkali metals are more preferable: oxides, hydroxide salts, carbonates, bicarbonates, hydrogen halides, carboxylates, amide salts, and zirconium salts.

In addition, the alkali metal constituting the above-mentioned alkali metal compound is preferably lithium, sodium, potassium, rubidium, or cesium, in view of high catalytic activity and the ability to obtain an ethylenically unsaturated group-containing acrylic resin with a high yield. , more preferably lithium.

As for the above-mentioned lithium compound, specifically, lithium oxide, lithium hydroxide, lithium carbonate, lithium fluoride, lithium chloride, lithium bromide, lithium acetate, lithium benzoate, lithium (meth)acrylate, acyl Lithium amide, lithium bis(trifluoromethylsulfonyl)imide, lithium acetylacetonate, and the like. Among them, lithium hydroxide is preferable.

As the above-mentioned alkali metal compound, a commercially available one may be used, or one produced by a known method or the like may be used. Moreover, an alkali metal compound may be used individually, and may use 2 or more types together.

The amount of the alkali metal compound used is not particularly limited as long as the acrylic resin containing an ethylenically unsaturated group can be produced, but it is usually 0.001 to 1000 mol% relative to the carboxylic acid (β) containing an ethylenically unsaturated group. 0.005-500mol%, especially preferably 0.01-250mol%. If the amount of alkali metal compound used is too small, it tends to be difficult to obtain the effect of further improving the yield of acrylic resins containing ethylenically unsaturated groups. If the amount of alkali metal compound used is too large, the yield cannot be further improved. The tendency is not in line with economic benefits.

[other optional ingredients] In addition, in the production method of (i), a solvent may be used as another optional component. As the solvent, the same ones as the organic solvents mentioned above for the production of the hydroxyl group-containing acrylic resin (α) can be used. The solvent may be used alone or as a mixed solvent of two or more. The usage-amount of a solvent is also not specifically limited, It can select suitably. There is no special limitation on the method of introducing the solvent into the reaction vessel. All the solvents can be introduced together at one time, a part or all of the solvents can be introduced in stages, or a part or all of the solvents can be introduced continuously import. In addition, an introduction method combining these methods may be used.

[Manufacturing method of (ii)] The conditions of the esterification reaction in the production method of (ii) above are not particularly limited, and the reaction conditions during the reaction process can also be appropriately changed.

The amount of the above-mentioned hydroxyl-containing acrylic resin (α) and (meth)acrylic anhydride (γ) used is relative to 100 mol% of the hydroxyl-containing monomer (a1) in the hydroxyl-containing acrylic resin (α), ( Meth)acrylic anhydride (γ) is usually 10 to 100 mol%, preferably 15 to 95 mol%, particularly preferably 20 to 90 mol%.

The reaction temperature of the above-mentioned esterification reaction is usually 20-90°C, preferably 30-80°C, and the reaction time is usually 2-40 hours, preferably 5-30 hours. In addition, in the production method of (ii), the ambient gas and pressure during the reaction are not particularly limited.

[magnesium compound] In addition, in the production method of (ii), when the acrylic resin containing a hydroxyl group and (meth)acrylic anhydride are subjected to an esterification reaction, it is preferable to use a magnesium compound as a catalyst. As the above-mentioned magnesium compound, the same ones as those listed in the production method of (i) above can be used. Moreover, a magnesium compound can be used individually or in combination of 2 or more types. Among them, it is suitable for magnesium: salts with inorganic acids, salts with organic acids, zirconium salts, more preferably magnesium hydroxides, carboxylates, acetylacetonate, especially magnesium hydroxide, (methyl ) magnesium acrylate, magnesium acetylacetonate.

In addition, the amount of the magnesium compound used is usually 0.01 to 10 mol%, preferably 0.05 to 5 mol%, with respect to 100 mol% of the hydroxyl group-containing monomer (a1) in the hydroxyl group-containing acrylic resin (α), preferably It is 0.1~1mol%.

[Any other ingredients] In addition, in the production method of (ii), a solvent can also be used as other optional components, and the same thing as described in the polymerization of the above-mentioned hydroxyl group-containing acrylic resin (α) can be used as a solvent. The solvent may be used alone or as a mixed solvent of two or more. Also, the amount of the solvent used and the method of introducing it into the reaction container are the same as the production method of (i) above.

[Ethylenically unsaturated group-containing acrylic resin] As a result, according to the production method of (i) or (ii) above, for example, an ethylenically unsaturated group-containing structure represented by the following general formula (1) can be efficiently obtained Part of the acrylic resin. Also, "R ¹ " in the following general formula is a substituent containing an ethylenically unsaturated group.

R¹ 係含有乙烯性不飽和基之取代基，R² 係含有選自C、O、N及S中至少一種之有機基(惟，胺甲酸酯基除外)，X係O或NH。[chemical 7]

R1 is ^a substituent containing an ethylenically unsaturated group, R2 is an organic group containing at least one of C, O, N and S ⁽ except for a carbamate group), and X is O or NH.

The above-mentioned ethylenically unsaturated group-containing acrylic resin contains a predetermined amount of specific ethylenically unsaturated group moieties in the side chain, so it is hardened by irradiation with active energy rays and has peelability. Also, the ethylenically unsaturated group structural site represented by the above-mentioned general formula (1) may be a side chain terminal of the acrylic resin, for example, the above-mentioned ethylenically unsaturated group-containing group may be directly bonded to the main chain of the acrylic resin. The structural site may be used as a side chain, and the above-mentioned ethylenically unsaturated group-containing structural site may be bonded to the end of the side chain of the acrylic resin having a side chain. Furthermore, the adhesive composition of the present invention containing the ethylenically unsaturated group-containing acrylic resin is excellent in adhesive force before active energy ray irradiation and peelability after active energy ray irradiation. In addition, the above-mentioned acrylic resin containing an ethylenically unsaturated group has excellent heat resistance because it does not have a urethane group in a structural part containing an ethylenically unsaturated group. It is also excellent in detachability.

The ethylenically unsaturated group introduction rate (esterification rate) of the above-mentioned ethylenically unsaturated group-containing acrylic resin is usually 10% of all hydroxyl-containing monomers (a1) in the hydroxyl-containing acrylic resin (α). % or more, preferably more than 20%, especially more than 30%. In addition, the upper limit value is usually 100%, and when the hydroxyl group derived from the hydroxyl group-containing monomer (a1) is used for the reaction with a crosslinking agent described later, the upper limit value is preferably 95%. Also, the upper limit of the reaction rate of ethylenically unsaturated group-containing carboxylic acid (β) or (meth)acrylic anhydride (γ) is usually 100%. When the ethylenically unsaturated group introduction ratio is too low, the peelability after active energy ray irradiation tends to decrease. In addition, the ethylenically unsaturated group introduction rate is calculated according to the following formula as the integral value ratio of the hydroxyl group-containing monomer (a1) before and after the esterification reaction obtained by ¹³ C-NMR measurement.

OH(α)：含有羥基之丙烯酸系樹脂(α)中之來自含有羥基之單體(a1)之積分值 OH(A)：含有乙烯性不飽和基之丙烯酸系樹脂中之來自含有羥基之單體(a1)之積分值[number 2]

OH(α): Integral value derived from hydroxyl-containing monomer (a1) in hydroxyl-containing acrylic resin (α) OH(A): Integral value derived from hydroxyl-containing monomer (a1) in ethylenically unsaturated group-containing acrylic resin Integral value of body (a1)

In the above-mentioned ethylenically unsaturated group-containing acrylic resin, the content of the ethylenically unsaturated group is 25 to 500 mmol/100 g relative to the ethylenically unsaturated group-containing acrylic resin. It is preferably 30-450mmol/100g, more preferably 40-400mmol/100g, especially 50-300mmol/100g. If the content of the ethylenically unsaturated group is too small, the peelability of the active energy ray irradiation will decrease, and if the content of the ethylenically unsaturated group is too high, the stain resistance to the workpiece after peeling will decrease.

The ethylenically unsaturated group content of the above-mentioned ethylenically unsaturated group-containing acrylic resin can be obtained by the following calculation.

E(a)：經酯化之含有羥基之單體(a1)之mol數 Mw(γ)：因酯化而附加之不飽和基之分子量 又，E(a)係將含有羥基之丙烯酸系樹脂(α)之聚合成分100重量%中之含有羥基之單體(a1)之重量%與乙烯性不飽和基導入率之乘積，除以含有羥基之單體(a1)之分子量。[number 3]

E(a): The number of moles of the esterified hydroxyl-containing monomer (a1) Mw(γ): The molecular weight of the unsaturated group added due to esterification. E(a) is an acrylic resin containing hydroxyl The product of the weight % of the hydroxyl group-containing monomer (a1) in 100 weight % of the polymerized component of (α) and the ethylenically unsaturated group introduction ratio is divided by the molecular weight of the hydroxyl group-containing monomer (a1).

Also, if the acrylic resin containing an ethylenically unsaturated group contains a hydroxyl group, it is preferable to form a crosslinked structure by reacting with a crosslinking agent described later to improve the adhesive force before irradiation with active energy rays.

The content of hydroxyl groups in the ethylenically unsaturated group-containing acrylic resin is usually 0.01 to 35% by weight, preferably 0.01 to 25% by weight. If the content of hydroxyl groups is too small, the cohesive force of the adhesive will decrease and cause residual glue. If the content of hydroxyl groups is too high, the flexibility and adhesion of the adhesive will decrease, and warping will occur between the adhesive and the workpiece. tendency. Also, the above-mentioned hydroxyl group contained in the acrylic resin containing an ethylenically unsaturated group refers to the acrylic resin (α) containing a hydroxyl group and the carboxylic acid (β) containing an ethylenically unsaturated group or (meth)acrylic anhydride ( Hydroxyl groups from unreacted hydroxyl-containing monomer (a1) after esterification of γ).

Moreover, when using the above-mentioned acrylic resin containing an ethylenically unsaturated group as an adhesive, it is preferably in a solution state. The viscosity at 25°C of the acrylic resin solution containing ethylenically unsaturated groups is preferably 5-50,000 mPa･s, more preferably 10-10,000 mPa･s. When the viscosity is out of the above range, the applicability tends to decrease when an ethylenically unsaturated group-containing acrylic resin is used as an adhesive. In addition, the measuring method of the viscosity uses an E-type viscometer.

[Crosslinking agent] In the adhesive composition of the present invention, in order to improve the adhesive force before irradiation with active energy rays, it is preferable to further contain a crosslinking agent. The above-mentioned cross-linking agent reacts with the functional group in the acrylic resin containing ethylenically unsaturated groups to form a cross-linking structure, such as isocyanate-based cross-linking agent, epoxy-based cross-linking agent, aziridine Aziridine-based crosslinking agents, melamine-based crosslinking agents, aldehyde-based crosslinking agents, amine-based crosslinking agents, and metal chelating agent-based crosslinking agents. Among these, it is preferable to use an isocyanate-based crosslinking agent from the viewpoint of improving the adhesiveness of the adherend and the viewpoint of reactivity with an ethylenically unsaturated group-containing acrylic resin.

The above-mentioned isocyanate-based cross-linking agents are those containing at least 2 or more isocyanate groups, such as aromatic polyisocyanates such as toluene diisocyanate, diphenylmethane diisocyanate, and xylylene diisocyanate; hexamethylene Aliphatic polyisocyanate such as diisocyanate; Alicyclic polyisocyanate such as isophorone diisocyanate and hydrogenated diphenylmethane diisocyanate; Adducts of reactants of low-molecular active hydrogen-containing compounds such as alcohol, propylene glycol, neopentyl glycol, trimethylolpropane, castor oil, etc. Among them, in view of chemical resistance and reactivity with functional groups, aromatic polyisocyanate, aromatic polyisocyanate and trimethylolpropane adducts are preferred, and cresyl diisocyanate and trimethylolpropane are particularly preferred. Adducts of trimethylolpropane.

Examples of the epoxy-based crosslinking agent include 1,3-bis(N,N'-diecidylaminomethyl)cyclohexane, N,N,N',N'- Tetraglycidyl-m-xylylenediamine, Ethylene Glycol Diglycidyl Ether, 1,6-Hexanediol Diglycidyl Ether, Trimethylolpropane Diglycidyl Ether, Diepoxide Propylaniline, Diglycidylamine, etc.

Examples of the aforementioned aziridine-based crosslinking agent include diphenylmethane-4,4'-bis(1-aziridine carboxamide), trimethylolpropane tris-β-aziridinyl Propionate, Tetramethylolmethane Tris-β-Aziridinylpropionate, Toluene-2,4-Bis(1-Aziridinecarboxamide), Triethylenemelamine, Bisisophthaloyl- 1-(2-methylaziridine), para-1-(2-methylaziridine)phosphine, trimethylolpropane tris-β-(2-methylaziridine)propionate, etc.

The above-mentioned melamine-based crosslinking agents include melamine, amine-containing methylol melamine obtained by condensation of melamine and formaldehyde, imine-containing methylol melamine, and hexamethylol melamine. methylol melamine derivatives, methanol, butanol and other lower alcohols reacted in methylol melamine derivatives and partially or completely etherified, partially or completely alkylated methylol melamine, partially or completely alkylated methylol melamine containing imine groups Alkylated methylol melamine, etc.

烷-2,3-二醇、1,3-雙(羥基甲基)-2-咪唑啶、二羥甲基脲、N-羥甲基丙烯醯胺、尿素甲醛樹脂、三聚氰胺甲醛樹脂等於水溶液中游離醛之醛系化合物、或苯甲醛、2-甲基苯甲醛、4-甲基苯甲醛、對羥基苯甲醛、間羥基苯甲醛等芳香族醛系化合物。As for the above-mentioned aldehyde-based crosslinking agent, for example, formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, glyoxal, glutaraldehyde, dialdehyde starch, hexamethylenetetramine, 1,4-bis

Alkane-2,3-diol, 1,3-bis(hydroxymethyl)-2-imidazolidine, dimethylolurea, N-methylolacrylamide, urea-formaldehyde resin, melamine-formaldehyde resin in aqueous solution Aldehyde compounds of free aldehydes, or aromatic aldehyde compounds such as benzaldehyde, 2-methylbenzaldehyde, 4-methylbenzaldehyde, p-hydroxybenzaldehyde, m-hydroxybenzaldehyde.

For the above-mentioned amine-based crosslinking agent, for example, 4,4'-methylene-bis(2-chloroaniline), modified 4,4'-methylene-bis(2-chloroaniline), di Ethyltoluenediamine.

The above-mentioned metal chelate-based crosslinking agents include, for example, chelate compounds in which the metal atoms are aluminum, zirconium, titanium, zinc, iron, tin, etc., and aluminum chelate compounds are preferred from the viewpoint of performance. In terms of aluminum chelates, for example, diisopropoxyaluminum monooleate acetyl acetate, monoisopropoxyaluminum dioleate acetylacetate, monoisopropoxyaluminum monooleate Ester Monoethyl Acetyl Acetate, Diisopropoxy Aluminum Monolaurate Acetyl Acetate, Diisopropoxy Aluminum Monostearate Acetyl Acetate, Diisopropoxy Aluminum Monoisohard Fatty acid acetyl acetate, etc.

These crosslinking agents may be used alone or in combination of two or more.

The content of the above-mentioned crosslinking agent is preferably 0.1-30 parts by weight, especially 0.2-20 parts by weight, and more preferably 0.2-15 parts by weight, relative to 100 parts by weight of the acrylic resin containing ethylenically unsaturated groups. . If the cross-linking agent is too small, the cohesion of the adhesive tends to decrease and cause residual glue. If the cross-linking agent is too large, the flexibility and adhesion of the adhesive decrease, and warping tends to occur between the cross-linking agent and the workpiece.

啉基(4-硫基甲基苯基)丙烷-1-酮、2-苯甲基-2-二甲基胺基-1-(4-

啉基苯基)丁酮、2-(二甲基胺基)-2-[(4-甲基苯基)甲基]-1-[4-(4-

啉基)苯基]-1-丁酮、2-羥基-2-甲基-1-[4-(1-甲基乙烯基)苯基]丙酮寡聚物等苯乙酮類； 苯偶因、苯偶因甲醚、苯偶因乙醚、苯偶因異丙醚、苯偶因異丁醚等苯偶因類； 二苯甲酮、鄰苯甲醯基苯甲酸甲酯、4-苯基二苯甲酮、4-苯甲醯基-4’-甲基-二苯基硫醚、3,3’,4,4’-四(第三丁基過氧羰基)二苯甲酮、2,4,6-三甲基二苯甲酮、4-苯甲醯基-N,N-二甲基-N-[2-(1-側氧基-2-丙烯氧基)乙基]苯四甲基溴化銨、(4-苯甲醯基苯甲基)三甲基氯化銨等二苯甲酮類； 2-異丙基噻噸酮、4-異丙基噻噸酮、2,4-二乙基噻噸酮、2,4-二氯噻噸酮、1-氯-4-丙氧基噻噸酮、2-(3-二甲基胺基-2-羥基)-3,4-二甲基-9H-噻噸酮-9-酮內氯化物等噻噸酮類； 2,4,6-三甲基苯甲醯基-二苯基氧化膦、雙(2,6-二甲氧基苯甲醯基)-2,4,4-三甲基-戊基氧化膦、雙(2,4,6三甲基苯甲醯基)-苯基氧化膦等醯基氧化膦類等。其中宜為苯乙酮類，尤宜為1-羥基環己基苯基酮、噻噸酮類，尤宜為2,4,6-三甲基苯甲醯基-二苯基氧化膦。 又，這些光聚合引發劑可單獨使用或可併用2種以上。[Photopolymerization Initiator] The adhesive composition of the present invention is preferably blended with a photopolymerization initiator from the viewpoint of improving peelability after irradiation with active energy rays. As far as the above-mentioned photopolymerization initiator is concerned, as long as it can generate free radicals due to the action of light, for example, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropane-1- Ketone, benzyl dimethyl ketal, 4-(2-hydroxyethoxy) phenyl-(2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexyl phenyl ketone, 1-[4-( 2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-methyl-2-

Linyl (4-thiomethylphenyl) propan-1-one, 2-benzyl-2-dimethylamino-1-(4-

Linylphenyl) butanone, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-

Phenyl) phenyl] -1-butanone, 2-hydroxy-2-methyl-1-[4-(1-methylvinyl) phenyl] acetone oligomers and other acetophenones; benzoin , benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether and other benzoins; benzophenone, methyl o-benzoyl benzoate, 4-phenyl Benzophenone, 4-benzoyl-4'-methyl-diphenylsulfide, 3,3',4,4'-tetrakis(tert-butylperoxycarbonyl)benzophenone, 2 ,4,6-trimethylbenzophenone, 4-benzoyl-N,N-dimethyl-N-[2-(1-oxo-2-propenyloxy)ethyl]benzene Benzophenones such as tetramethylammonium bromide, (4-benzoylbenzyl)trimethylammonium chloride; 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2 ,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 1-chloro-4-propoxythioxanthone, 2-(3-dimethylamino-2-hydroxyl)-3 ,4-Dimethyl-9H-thioxanthone-9-one internal chloride and other thioxanthones; 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis(2,6 Oxidation of acyl groups such as -dimethoxybenzoyl)-2,4,4-trimethyl-pentylphosphine oxide, bis(2,4,6trimethylbenzoyl)-phenylphosphine oxide Phosphines etc. Among them, acetophenones are preferred, 1-hydroxycyclohexyl phenyl ketone and thioxanthone are especially preferred, and 2,4,6-trimethylbenzoyl-diphenylphosphine oxide is especially preferred. Moreover, these photoinitiators may be used individually or in combination of 2 or more types.

As far as the content of the above-mentioned photopolymerization initiator is concerned, it is preferably 0.1-20 parts by weight, especially 0.5-15 parts by weight, and especially 0.5 parts by weight relative to 100 parts by weight of the acrylic resin containing ethylenically unsaturated groups. ~10 parts by weight. If the content of the photopolymerization initiator is too small, the curability of the acrylic resin containing an ethylenically unsaturated group tends to be low when irradiated with active energy rays, and the peelability after irradiation with active energy rays tends to decrease. The tendency to increase the contamination of the processed components.

Also, as auxiliary agents for these photopolymerization initiators, for example, triethanolamine, triisopropanolamine, 4,4'-dimethylaminobenzophenone (Michelerone), 4, 4'Diethylaminobenzophenone, 2-dimethylaminoethylbenzoic acid, ethyl 4-dimethylaminobenzoate, 4-dimethylaminobenzoic acid (n-butoxy ) ethyl ester, isoamyl 4-dimethylaminobenzoate, 2-ethylhexyl 4-dimethylaminobenzoate, 2,4-diethylthioxanthone, 2,4-diiso Propylthioxanthone, etc. These auxiliary agents may be used alone or in combination of two or more.

[other ingredients] In the adhesive composition of the present invention, in the range that does not impair the effect of the present invention, it is also preferable to further incorporate, for example, an ethylenically unsaturated compound from the viewpoint of peelability after irradiation with active energy rays, and may further contain Additives such as antistatic agents, antioxidants, plasticizers, fillers, pigments, thinners, antiaging agents, ultraviolet absorbers, ultraviolet stabilizers, and adhesive resins. These additives may be used alone or in combination of two or more. Antioxidants are especially effective for maintaining the stability of the adhesive layer. The content when the antioxidant is blended is not particularly limited, but is preferably 0.01 to 5% by weight. In addition, in addition to additives, a small amount of impurities contained in the manufacturing raw materials of the constituent components of the adhesive composition may be contained.

In this way, the adhesive composition of the present invention can be obtained by mixing an acrylic resin containing an ethylenically unsaturated group, preferably a crosslinking agent, a photopolymerization initiator, and other components as needed.

The adhesive composition of the present invention is cross-linked by the above-mentioned cross-linking agent to exert its performance as an adhesive, and then, by irradiating active energy rays, the ethylenically unsaturated group-containing acrylic resin contains The base will polymerize and the adhesive will harden, and the peelability will be exhibited due to the decrease of the adhesive force.

The adhesive composition of the present invention is ideally used as an adhesive sheet for temporarily protecting the surface when processing electronic substrates, semiconductor wafers, glass processed products, metal plates, plastic plates, and other processed members. agent layer. Furthermore, since the adhesive sheet of the present invention is excellent in heat resistance, even if it is attached to the surface of the workpiece and then heated at 100°C or higher, it can exhibit excellent peelability by irradiating active energy rays. The above-mentioned adhesive sheet will be described below.

The above-mentioned adhesive sheet usually has a base sheet, an adhesive layer composed of the adhesive composition of the present invention, and a release film. In terms of the production method of the adhesive sheet, firstly, the adhesive composition of the present invention is directly used, or the concentration is adjusted with an appropriate organic solvent, and then directly coated on the release film or the substrate sheet. Thereafter, drying is performed by, for example, heat treatment at 80 to 105° C. for 0.5 to 10 minutes, and the adhesive sheet can be obtained by affixing it to a base material sheet or a release film. In addition, in order to obtain a balance of adhesive properties, it is also possible to perform aging after drying.

Examples of the aforementioned substrate sheet include polyethylene naphthalate, polyethylene terephthalate, polybutylene terephthalate, polyethylene terephthalate/isophthalic acid Polyester resins such as copolymers; polyolefin resins such as polyethylene, polypropylene, and polymethylpentene; polyvinyl fluoride resins such as polyvinyl fluoride, polyvinylidene fluoride, and polyvinyl difluoride; nylon 6 , nylon 6, 6 and other polyamides; polyvinyl chloride, polyvinyl chloride/vinyl acetate copolymer, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, polyvinyl alcohol, vinylon and other ethylene polymers; Cellulose resins such as cellulose triacetate and cellophane; acrylic resins such as polymethyl methacrylate, polyethyl methacrylate, polyethyl acrylate, and polybutyl acrylate; polystyrene; polycarbonate; Polyarylate; polyimide and other synthetic resin sheets, aluminum, copper, iron metal foil, high-quality paper, cellophane and other papers, fabrics and non-woven fabrics made of glass fibers, natural fibers, synthetic fibers, etc. These base material sheets can be used as a single-layer body or a multi-layer body in which two or more types are laminated. Among them, a synthetic resin sheet is preferable in consideration of light weight and the like.

In addition, as the above-mentioned release film, for example, various synthetic resin sheets, paper, woven fabrics, non-woven fabrics, and the like that have been subjected to a release treatment can be used as examples for the above-mentioned base sheet.

Also, the coating method of the above-mentioned adhesive composition is not particularly limited as long as it is a general coating method, and examples thereof include roll coating, die coating, gravure coating, and chipped wheel coating. , screen printing and other methods.

The thickness of the adhesive layer of the above-mentioned adhesive sheet is usually preferably 10-200 μm, more preferably 15-100 μm.

In terms of the above aging conditions, the temperature is usually room temperature (23°C) to 70°C, and the time is usually 1 to 30 days. Specifically, for example, 1 to 20 days at 23°C, 3 to 10 days at 23°C , 40°C for 1 to 7 days, etc.

The adhesive sheet of the present invention reduces the adhesive force by irradiating active energy rays. For the above-mentioned active energy rays, light rays such as far ultraviolet rays, ultraviolet rays, near ultraviolet rays, and infrared rays can be used; electromagnetic waves such as X-rays and gamma rays; In addition, electron beams, proton beams, neutron beams, and the like can be used. Among them, ultraviolet rays are preferable in consideration of curing speed, availability of irradiation equipment, and price.

The cumulative exposure dose when irradiating the above-mentioned ultraviolet rays is usually 50 to 3,000 mJ/cm ² , preferably 100 to 1,000 mJ/cm ² . In addition, the irradiation time varies depending on the type of light source, the distance between the light source and the adhesive layer, the thickness of the adhesive layer, and other conditions. It is usually several seconds, and may be a fraction of a second depending on the situation.

The adhesive force of the above-mentioned adhesive sheet varies depending on the type of base sheet and the type of workpiece to be processed. Before irradiation with active energy rays, the adhesive force is preferably 0.1-30N/25mm, more preferably 0.5-20N/25mm. Also, the adhesive force after irradiation with active energy rays is preferably 1 N/25 mm or less, more preferably 0.5 N/25 mm or less. The adhesive force after the active energy ray irradiation is preferably 1/10 or less, more preferably 1/20 or less, of the adhesive force before the active energy ray irradiation.

In addition, the adhesive force of the adhesive sheet of the present invention after heating at 150°C for 1 hour and then irradiating with ultraviolet light (accumulative irradiation dose: 250mJ/cm ² ) is preferably less than 1N/25mm, more preferably less than 0.5N/25mm. In the case of heating at 150° C. for 1 hour, the adhesive strength after irradiation with active energy rays is preferably 1/5 or less, more preferably 1/10 or less, of the adhesive strength before irradiation with active energy rays.

In addition, the adhesive force of the adhesive sheet of the present invention when heated at 200°C for 1 hour and then irradiated with ultraviolet light (cumulative irradiation dose: 250mJ/cm ² ) is preferably less than 2N/25mm, more preferably less than 1N/25mm. In the above-mentioned case of heating at 200°C for 1 hour, the adhesive force after the active energy ray irradiation is preferably 1/2 or less, more preferably 1/3 or less, of the adhesive force before the active energy ray irradiation.

The adhesive composition of the present invention, for example, can harden the adhesive layer by irradiating active energy rays as needed after bonding the member to be processed with an adhesive sheet as the adhesive layer and temporarily protecting the surface of the member to be processed. The adhesive force is reduced, and it can be easily peeled off from the processed member. In addition, since the adhesive sheet of the present invention has excellent heat resistance, after being attached to the surface of the workpiece, even if a heating step of, for example, 100° C. or higher, especially 150° C. Rays can also exhibit excellent peelability. [Example]

The following examples are given to illustrate the present invention more specifically, but the present invention is not limited to the following examples unless the gist thereof is exceeded. In addition, "part" below means a weight basis.

>Preparation of hydroxyl-containing acrylic resin (α) and carboxyl-containing acrylic resin (α’)> Before the examples, the acrylic resin (α) containing a hydroxyl group and the acrylic resin (α’) containing a carboxyl group were prepared earlier.

[Preparation Example 1] Feed ethyl acetate and azobisisobutyronitrile (AIBN) into a 2L round-bottomed four-neck flask, and while making it reflux, spend 2 hours to drop butyl acrylate (BA), 2-hydroxyethyl acrylate ( 2HEA), add ethyl acetate and AIBN appropriately, and react for 7.5 hours to obtain a solution of acrylic resin (α-1) containing hydroxyl groups. Also, the monomer composition of hydroxyl-containing acrylic resin (α-1) is BA/2HEA=72/28 (weight ratio), the weight average molecular weight is 470,000, the glass transition temperature is -23.7°C, and the solid content is 45.7% by weight %, viscosity is 12,600mPa･s/25℃. Also, the acid value of the hydroxyl group-containing acrylic resin (α-1) was 0.09 mgKOH/g.

[Preparation Example 2] Feed ethyl acetate and azobisisobutyronitrile (AIBN) into a 2L round-bottomed four-neck flask, and reflux while adding butyl acrylate (BA) and methyl methacrylate (MMA) dropwise for 2 hours , 2-hydroxyethyl acrylate (2HEA), add ethyl acetate and AIBN appropriately, and react for 7.5 hours to obtain a solution of acrylic resin (α-2) containing hydroxyl groups. In addition, the monomer composition of hydroxyl-containing acrylic resin (α-2) is BA/MMA/2HEA=62/10/28 (weight ratio), the weight average molecular weight is 600,000, the glass transition temperature is -35.3°C, solid The composition is 40% by weight, and the viscosity is 6,000mPa･s/25℃. Also, the acid value of the hydroxyl group-containing acrylic resin (α-2) was 0.09 mgKOH/g.

[Preparation Example 3] Feed ethyl acetate and azobisisobutyronitrile (AIBN) into a 2L round-bottomed four-neck flask, and while refluxing, add butyl acrylate (BA) and acrylic acid (AAc) dropwise for 2 hours, then add appropriately Ethyl acetate and AIBN were reacted for 5 hours to obtain a carboxyl-containing acrylic resin (α'-1) solution. Also, the monomer composition of the carboxyl group-containing acrylic resin (α'-1) is BA/AAc=80/20 (weight ratio), the weight average molecular weight is 710,000, the glass transition temperature is -35.7°C, and the solid content is 35.0 % by weight, viscosity is 15,000mPa･s/25℃. Also, the acid value of the carboxyl group-containing acrylic resin (α'-1) was 156 mgKOH/g.

Using the hydroxyl group-containing acrylic resin (α) and carboxyl group-containing acrylic resin (α') obtained above, an ethylenically unsaturated group-containing acrylic resin was produced.

>Manufacturing Example 1> The hydroxyl-containing acrylic resin (α-1) prepared above was mixed with 80 mol% of acrylic acid ( AAc)(β-1), 0.50 mol% magnesium hydroxide relative to acrylic acid, and 0.50 mol% lithium hydroxide were each fed into a 2L round-bottomed four-neck flask, and the temperature was raised to 60°C while stirring. Then, spend 6 hours dropwise adding a 50% toluene solution of di-tert-butyl dicarbonate (I-1) with the same mole as the acrylic acid fed, and then react at 60°C for 10 hours to obtain acrylic acid containing ethylenically unsaturated groups. Department of resin (1). During the reaction, no significant increase in viscosity was observed, and the reaction proceeded favorably. The obtained ethylenically unsaturated group-containing acrylic resin (1) had a solid content of 34.4% by weight, a viscosity of 2,300 mPa･s/25°C, and an esterification rate calculated from the results of ¹³ C-NMR measurements of 76.9% ( The reaction rate is 96.1%), and the ethylenically unsaturated group content is 165mmol/100g.

>Manufacturing Example 2> The hydroxyl-containing acrylic resin (α-2) prepared above was mixed with 80 mol% of methyl Acrylic anhydride (γ-1) and 0.40 mol% magnesium hydroxide as an esterification catalyst were fed into a 2L round-bottomed four-neck flask, stirred and reacted at 50°C for 18 hours to obtain ethylenically unsaturated group-containing Acrylic resin (2). The obtained ethylenically unsaturated group-containing acrylic resin (2) had a solid content of 31.8% by weight, a viscosity of 800 mPa･s/25°C, and an esterification rate calculated from the results of ¹³ C-NMR measurements of 64% (reaction The rate is 80%), and the content of ethylenically unsaturated group is 140mmol/100g.

> Production Example 3 > In Production Example 2, methacrylic anhydride (γ-1) was changed to 33 mol% with respect to 100 mol% of the hydroxyl group-containing monomer in the hydroxyl group-containing acrylic resin (α-2) and used as Except having changed the magnesium hydroxide of an esterification catalyst into 0.16 mol%, it carried out similarly to manufacture example 2, and obtained the ethylenically unsaturated group containing acrylic resin (3). The obtained ethylenically unsaturated group-containing acrylic S resin (3) had a solid content of 31.9% by weight, a viscosity of 1,000mPa･s/25°C, and an esterification rate calculated from the results of ¹³ C-NMR measurements of 33%. (Reaction rate is 100%), and the content of ethylenically unsaturated group is 72mmol/100g.

>Manufacturing Example 4> With respect to 100mol% of the hydroxyl-containing monomer in the hydroxyl-containing acrylic resin (α-2) obtained in the above-mentioned Preparation Example 2, 80mol% of 2-methacryloxyethyl acrylic acid was appropriately added The ester (MOI) was reacted with dibutyltin dilaurate as a urethanization catalyst at 50°C for 18 hours to obtain an acrylic resin (1') containing ethylenically unsaturated groups. The obtained ethylenically unsaturated group-containing acrylic resin (1') has a solid content of 35.0% by weight, a viscosity of 1,200mPa･s/25°C, and a urethane conversion rate calculated from the results of ¹³ C-NMR measurement It is 80% (the reaction rate is 100%), and the content of ethylenically unsaturated group is 148mmol/100g.

> Production Example 5 > In Production Example 2, methacrylic anhydride (γ-1) was changed to 8.4 mol% and Except having changed the magnesium hydroxide which is an esterification catalyst into 0.04 mol%, it carried out similarly to manufacture example 2, and obtained the ethylenically unsaturated group containing acrylic resin (2'). The obtained ethylenically unsaturated group-containing acrylic resin (2') had a solid content of 31.4% by weight, a viscosity of 1,500 mPa･s/25°C, and an esterification rate calculated from the results of ¹³ C-NMR measurements of 8.4%. (Reaction rate is 100%), and the content of ethylenically unsaturated group is 20mmol/100g.

>Manufacturing example 6> The carboxyl group-containing acrylic resin (α'-1) prepared above, 2HEA of 80 mol% relative to the carboxyl group-containing monomer 100 mol% in the carboxyl group-containing acrylic resin (α'-1), and the relative 2HEA: 0.50 mol% magnesium hydroxide and 0.50 mol% lithium hydroxide were each fed into a 2L round-bottomed four-neck flask, and the temperature was raised to 60°C while stirring. Then, a 50% toluene solution of di-tert-butyl dicarbonate (I-1) having the same mole as the feed 2HEA was added dropwise for 6 hours. Immediately after the dropwise addition was started, the viscosity gradually increased, and the reaction was difficult to continue, so the reaction was stopped on the way.

The presence or absence of urethane groups and the content of ethylenically unsaturated groups in the ethylenically unsaturated group-containing acrylic resins obtained in Production Examples 1 to 6 are shown in Table 1 below.

[Table 1]

>Example 1> With respect to 100 parts of the solid content of the ethylenically unsaturated group-containing acrylic resin (1) obtained above, 1.0 part of an isocyanate-based crosslinking agent (manufactured by Nippon Polyurethane Co., Ltd. "CORONATE L-55E") and 3.00 parts of a photopolymerization initiator ("Irgacure 184" manufactured by BASF Corporation) was used to prepare an active energy ray-curable adhesive composition. Moreover, the compounding of Example 1 is shown in Table 2 mentioned later.

>Example 2, 3 and Comparative Example 1, 2> In Example 1, the type of acrylic resin containing an ethylenically unsaturated group, an isocyanate-based crosslinking agent, and a photopolymerization initiator were blended and mixed according to Table 2 below to prepare Examples 2 and 3 and Comparative Example 1 2. The active energy ray-curable adhesive composition.

By applying the adhesive compositions of Examples 1 to 3 and Comparative Examples 1 and 2 above to a polyimide film (film thickness 50 μm) (manufactured by TORAY-DU PONT Co., Ltd. KAPTON 200H"), dried, attached to a 38 μm separation membrane (manufactured by Mitsui Chemicals Tohcello, "SP-PET 38 01-BU"), and aged at 40°C for 3 days to produce an adhesive sheet. With respect to the obtained adhesive sheet, the following evaluations were performed. The evaluation results are shown in Table 2 below.

>Adhesive force before active energy ray irradiation> Make a test piece of 25mm x 100mm from the adhesive sheet obtained above, peel off the separation film, press and attach a rubber roller weighing 2kg back and forth twice to the Corning glass plate under the environment of 23°C and 50%RH. After standing in the same environment for 30 minutes, the 180-degree peel strength (N/25mm) was measured at a peeling speed of 300mm/min. The evaluation criteria are as follows. (Assessment basis) ◎･･･6.0N/25mm or more ○･･･More than 3.0N/25mm and less than 6.0N/25mm ×･･･Less than 3.0N/25mm

>Adhesive force after active energy ray irradiation> Make a 25mm×100mm test piece from the above-mentioned adhesive sheet, peel off the separation film, and apply the rubber roller with a weight of 2kg back and forth twice under the environment of 23°C and 50%RH. Press and attach to the Corning glass plate, after standing in the same environment for 30 minutes, use an 80W high-pressure mercury lamp to apply ultraviolet radiation from the side of the glass plate (cumulative exposure 250mJ/cm ² ), and immediately peel off at a speed of 300mm/min Measure the 180-degree peel strength (N/25mm). The evaluation criteria are as follows. (Evaluation criteria) ◎･･･less than 0.1N/25mm ○･･･more than 0.1N/25mm and less than 1N/25mm×･･･more than 1N/25mm

>Adhesive force after heating and irradiating active energy rays (150°C)> Make a test piece of 25mm×100mm from the above-mentioned adhesive sheet, peel off the separation film, and put 2kg of rubber under the environment of 23°C and 50%RH The roller goes back and forth twice to apply pressure to the Corning glass plate, and put it into an oven jet dryer heated to 150°C for 1 hour. Take it out of the dryer, cool it at 23°C and 50%RH for 30 minutes, then use an 80W high-pressure mercury lamp to irradiate the glass plate with ultraviolet light (accumulative exposure amount 250mJ/cm ² ), and immediately peel off Measure the 180-degree peel strength (N/25mm) at a speed of 300mm/min. The adherend after peeling was visually confirmed, and the stain resistance was evaluated. The evaluation criteria are as follows. (Evaluation criteria: Adhesion) ◎･･･Less than 0.5N/25mm ○･･･0.5N/25mm or more and 1.0N/25mm or less ×･･･More than 1.0N/25mm (Evaluation criteria: Pollution resistance) ◎･･･No glue residue ○･･･Slight glue residue×･･･There is glue residue all over

>Adhesive force after heating and irradiating active energy rays (200°C)> Make a 25mm×100mm test piece from the above-mentioned adhesive sheet, peel off the separation film, and put 2kg of rubber in the environment of 23°C and 50%RH Roll back and forth twice to apply pressure to the Corning glass plate, and put it into an oven jet dryer heated to 200°C for 1 hour. Take it out of the dryer, cool it at 23°C and 50%RH for 30 minutes, then use an 80W high-pressure mercury lamp to irradiate the glass plate with ultraviolet light (accumulative exposure amount 250mJ/cm ² ), and immediately peel off Measure the 180-degree peel strength (N/25mm) at a speed of 300mm/min. The adherend after peeling was visually confirmed, and the stain resistance was evaluated. The evaluation criteria are as follows. (Evaluation criteria: Adhesion) ◎･･･Less than 0.5N/25mm ○･･･0.5N/25mm or more and 2.0N/25mm or less ×･･･More than 2.0N/25mm (Evaluation criteria: Contamination resistance) ◎･･･No glue residue ○･･･Slight glue residue×･･･There is glue residue all over

※比較例1：加熱、照射活性能量射線後(150℃)，基材界面剝離且被黏體有全面殘膠[Table 2]

※Comparative example 1: After heating and irradiating active energy rays (150°C), the substrate interface peeled off and there was a full amount of adhesive residue on the adherend

As can be seen from the above Table 2, in Examples 1 to 3, which contain an acrylic resin containing an ethylenically unsaturated group and the acrylic resin has a specific structural site containing an ethylenically unsaturated group in a predetermined amount, the active energy is irradiated. Excellent adhesion before irradiation and peelability after irradiation with active energy rays. In addition, even after heating at 150° C. and 200° C., Examples 1 to 3 showed reduced adhesive force and excellent stain resistance after being irradiated with active energy rays. On the other hand, Comparative Example 1 using an acrylic resin that does not have a specific ethylenically unsaturated group-containing structural site had high adhesive force before active energy ray irradiation and low adhesive force after active energy ray irradiation. After that, the adhesion is high and the pollution resistance is also poor. In addition, Comparative Example 2 using an acrylic resin that does not contain a specific ethylenically unsaturated group-containing structural site in a predetermined amount has high adhesive force after active energy ray irradiation and adhesive force after heating, and poor peelability.

In the above-mentioned embodiment, the specific forms in the present invention are shown, but the above-mentioned embodiment is only an illustration, and shall not be interpreted as a limitation. Various modifications that are obvious to those skilled in the art to which the invention pertains are also included in the scope of the present invention. [industrial availability]

The adhesive composition of the present invention can be ideally used as an adhesive composition for temporary surface protection adhesive films when electronic substrates, semiconductor wafers, glass processed products, metal plates, plastic plates, etc. are processed.

Claims (15)

An adhesive composition, comprising: an acrylic resin containing an ethylenically unsaturated group; the acrylic resin containing an ethylenically unsaturated group contains an ethylenically unsaturated group represented by the following general formula (1) in the side chain of the acrylic resin The structural part of the saturated group, and the content of the ethylenically unsaturated group is 25~500mmol/100g relative to the acrylic resin containing the ethylenically unsaturated group;

R ¹ is a substituent containing an ethylenically unsaturated group; R ² is an organic group containing at least one selected from C, O, N and S, except for a carbamate group; X is O or NH. As for the adhesive composition of claim 1, wherein the acrylic resin containing an ethylenically unsaturated group contains a hydroxyl group. If the adhesive composition of claim 1 or 2 of the scope of patent application, it further contains a cross-linking agent. Such as the adhesive composition of claim 1 or 2 of the scope of application, it further contains a photopolymerization initiator. Such as the adhesive composition of claim 1 or 2, wherein the ethylenically unsaturated group-containing acrylic resin is made of a hydroxyl-containing acrylic resin (α) and an ethylenically unsaturated group-containing carboxylic acid ( β) reacted in the presence of the compound (I) represented by the following general formula (2);

Here, R ³ and R ⁴ represent a hydrocarbon group with 1 to 20 carbon atoms. Such as the adhesive composition of claim 1 or 2, wherein the ethylenically unsaturated group-containing acrylic resin is made of hydroxyl-containing acrylic resin (α) and (meth)acrylic anhydride (γ) formed by esterification reaction. An adhesive sheet has an adhesive layer formed by cross-linking the adhesive composition according to any one of items 1 to 6 in the scope of the patent application. An adhesive sheet according to claim 7 of the patent application, wherein, when the adhesive sheet is applied to the surface of the adherend and then subjected to a heating step of 150°C or higher, the adhesive layer can be hardened by subsequent irradiation of active energy rays and stripped. A method for producing an acrylic resin containing an ethylenically unsaturated group, characterized in that: the acrylic resin (α) containing a hydroxyl group and the carboxylic acid (β) containing an ethylenically unsaturated group are represented by the following general formula (2): The reaction is carried out in the presence of the compound (I); the content of the ethylenically unsaturated group is 25 ~ 500mmol/100g relative to the acrylic resin containing the ethylenically unsaturated group;

Here, R ³ and R ⁴ represent a hydrocarbon group with 1 to 20 carbon atoms. Such as the production method of the ethylenically unsaturated group-containing acrylic resin of claim 9, wherein the hydroxyl-containing acrylic resin (α) and the ethylenically unsaturated-group-containing carboxylic acid (β) are mixed When the reaction is carried out in the presence of the compound (I) represented by the general formula (2), the reaction is further carried out in the presence of one or more magnesium compounds and one or more alkali metal compounds. A method for producing an ethylenically unsaturated group-containing acrylic resin as claimed in claim 10, wherein the alkali metal compound constitutes the alkali metal lithium. A method for producing an acrylic resin containing an ethylenically unsaturated group according to any one of items 9 to 11 of the scope of the patent application, wherein the compound (I) represented by the general formula (2) is di-tertiary butyl dicarbonate . The method for producing an ethylenically unsaturated group-containing acrylic resin as claimed in claim 10 or 11, wherein the magnesium is present in an amount of 0.001 to 1000 mol% relative to the ethylenically unsaturated group-containing carboxylic acid (β). The reaction is carried out in the presence of the compound and 0.001 to 1000 mol% of the alkali metal compound. The method for producing an ethylenically unsaturated group-containing acrylic resin according to any one of claims 9 to 11 of the patent claims, wherein the hydroxyl-containing monomer (a1) constituting the hydroxyl-containing acrylic resin (α) The content of the polymer is 0.1 to 50% by weight relative to the entire polymerization component. The method for producing an ethylenically unsaturated group-containing acrylic resin according to any one of claims 9 to 11, wherein the acid value of the hydroxyl-containing acrylic resin (α) is 10 mgKOH/g or less.