JPH11343471A - Adhesive composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject adhesive composition that has high initial adhesion, high storage stability and shows good peelability after curing by using a specific acrylic polymer and a specific monomer at a specific ratio. SOLUTION: This adhesive composition comprises (A) 100 pts.wt. of an acrylic polymer that is prepared by polymerizing (i) 100 pts.wt. of monomers mainly comprising an acrylic ester of the formula I (R1 is H, methyl; R2 is a 1-18C alkyl), (ii) 0-29 pts.wt. of a reactive unsaturated monomer that is copolymerizable with the component (i) and bears at least one group selected from OH, COOH, epoxy and other groups, (iii) 0.5-15 pts.wt. of a double bond-bearing peroxy compound of formula II (R3 is H, a 1-5C alkyl; R4 and R5 are each a 1-4C alkyl; R6 is H, a 1-12C alkyl; n is 0-4) where 100 pts.wt. of the component (i) and 0.5-30 pts.wt. of the total of components (ii) and (iii) are polymerized so that the peroxy groups may distribute therein and (B) 35-150 pts.wt. of a monomer bearing 3 or more acryloyl groups in every molecule.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to various kinds of adherends,
For example, metal plates, plastic resin plates, glass plates, various plastic films, various metal foils, semiconductor wafers,
The present invention relates to an ultraviolet or electron beam-curable pressure-sensitive adhesive composition suitable for use in surface protection and temporary fixing of mechanical parts, electric parts and the like.

[0002]

2. Description of the Related Art Conventionally, as a pressure-sensitive adhesive composition for surface protection and temporary fixing of parts, a composition obtained by vulcanizing natural rubber or various synthetic rubbers, a carboxyl group, a hydroxyl group,
A composition is used in which an acrylic copolymer having a reactive functional group such as a methylol group or an epoxy group is subjected to a cross-linking reaction with a polyisocyanate, an organometallic compound, a melamine resin, or the like.

[0003]

However, such a conventional example has the following problems. That is, when a pressure-sensitive adhesive tape obtained by applying a pressure-sensitive adhesive of the above composition to paper, resin laminated paper, plastic film, or the like and cross-linking is used for surface protection or fixing of parts, the elasticity and fluidity generally provided by the pressure-sensitive adhesive Thus, (1) the adhesive strength increases with the elapse of time after sticking to the adherend. (2) When stacked, the adhesive flows into the uneven portions of the adherend, and the adhesive strength increases. (3) When heat, pressure, temperature, and other treatments are required in the processing step, the increase in adhesive strength is even more remarkable. Therefore, when the tape is peeled after achieving the initial purpose such as temporary fixing, damage to the substrate of the adhesive tape, damage to the adherend, Transfer of the agent occurs, and as a result, there have been problems such as defective products and reduced workability. In addition, when the parts of the adherend are distorted or not smooth, if these are adhered and then immersed in an acid or alkaline solution, the adhesive tape will float, peel,
Problems such as intrusion of liquid have occurred.

Therefore, in recent years, in order to solve such a problem, an adhesive composition which is cured by an electron beam to reduce the adhesive strength has been proposed (for example, Japanese Patent Application Laid-Open No. Sho 62-62).
-10180, JP-A-62-138576, JP-A-1-2498, JP-A-1-11058
No. 4, JP-A 1-225285, etc.). However, in the case of such a conventional example, initial adhesive strength and cohesive strength were not so high, and storage properties in the bonded state, stability, and further, satisfactory properties such as peelability after electron beam irradiation could not be obtained. .

[0005] The present invention has been made in view of the above points of the prior art, and an object of the present invention is to provide a pressure-sensitive adhesive composition having a high initial adhesive strength, excellent storage stability, and good releasability after curing. Is to provide.

[0006]

Means for Solving the Problems The pressure-sensitive adhesive composition of the present invention has a general formula

Embedded image And a hydroxyl group, a carboxyl group, an epoxy group, an amino group and a derivative, which are copolymerizable with the above-mentioned acrylic ester (a), based on 100 parts by weight of a monomer mainly composed of the acrylic ester (a). Reactive monomers (b) having at least one group of
Parts by weight, general formula

Embedded image A peroxy compound (c) having a double bond
5 to 15 parts by weight, and the total amount of the reactive monomer (b) and the peroxy compound (c) is 0.5 to 30 parts by weight based on 100 parts by weight of the acrylic ester (a). 100 parts by weight of an acrylic polymer polymerized so that the peroxy group of the peroxy compound (c) is present, and 35 to 150 parts by weight of a monomer having three or more acryloyl groups in one molecule. It is a thing.

The acrylic ester (a), which is the main component of the pressure-sensitive adhesive composition, has a general formula

Embedded image And specifically, methyl acrylate, ethyl acrylate, butyl acrylate, 2-methyl acrylate, ethyl methacrylate, butyl methacrylate, isobutyl methacrylate, 2-ethylhexyl methacrylate, dodecyl methacrylate, etc. Is raised.

[0008] The reactive unsaturated monomer (b) is
In the molecule, a hydroxyl group -OH, a carboxyl group -COOH, A monomer having a double bond and at least one reactive group such as an amino group -NH ₂ or a derivative thereof, for example, acrylic acid, methacrylic acid, N-methylolacrylamide, glycidyl methacrylamide, allyl glycidyl ether , 2-hydroxyethyl acrylate, 2
-Hydroxy methacrylate, 2-hydroxypropyl acrylate, 2-hydroxy methacrylate, maleic anhydride and the like.

Further, the peroxy compound (c) is
General formula

Embedded image And t-butyl peroxyvinyl carbonate, t-hexylperoxyvinyl carbonate, t-butylperoxydiisopropenyl carbonate, t-butylperoxyacrylic carbonate, t-hexylperoxyallyl carbonate, etc. . By copolymerizing the peroxy compound with the acrylic ester, a cross-linking function is imparted to the obtained copolymer.

The above-mentioned monomers are mixed at a predetermined ratio, and in a suitable solvent in the presence of a polymerization initiator under polymerization conditions at a relatively low temperature that does not cause decomposition of the peroxy compound (c). The acrylic polymer is obtained by copolymerization according to a conventional method. Examples of the polymerization initiator that can be used here include an azo-based polymerization initiator and a peroxy-based polymerization initiator, but a sufficient polymerization reaction can be performed even at such a low temperature that the peroxy compound blended as the copolymerization component does not decompose. You need to choose something that can proceed.

Preferred azo polymerization initiators include, for example, azobisisobutyronitrile, 2,2'-azobis (2,4) dimethylvaleronitrile, 1,1'azobis (cyclohexane) carbonitrile, 2,2 '-Azobis (4-methoxy2,4-dimethyltylvaleronitrile), 2,2'-azobis (2-cyclopropylpropionitrile), 2,2'-azobis (2-methylbutyronitrile), 1,1 '-Azobis (cyclohexane-1
-Carbonitrile) and the like.

Preferred peroxy-based polymerization initiators include, for example, t-butylperoxypivalate, t-butylperoxyneodecanolate, t-butylperoxyisobutyrate, walnut peroxyneodecanolate, t-butylperoxy (2- Ethylhexanoate) benzoyl peroxide, lauroyl peroxide, decanoyl peroxide, benzoyl peroxide, methanol peroxide, and the like.

On the other hand, the monomer having three or more acryloyl groups in one molecule includes, for example, a compound represented by the following general formula:

Embedded image Are preferred. Examples of such compounds include, for example, tetramethylol methane triacrylate, tetramethylol methane tetraacrylate, trimethylol propane triacrylate, trimethylol butane triacrylate, trimethylol pentane triacrylate, and ethylene oxide and propylene oxide adducts of the above acrylates. Is raised.

The monomer having three or more acryloyl groups in one molecule includes, for example, a compound represented by the following general formula:

Embedded image And a compound having three or more acryloyl groups via an ether bond is also preferable. Examples of such compounds include dipentaerythrit triacrylate, dipentaerythrit tetraacrylate, dipentaerythrit pentaacrylate, dipentaerythrit hexaacrylate, and the above-mentioned adducts of ethylene oxide or propylene oxide.

Further, a photoinitiator can be added to the pressure-sensitive adhesive composition of the present invention. The addition amount is preferably 0.1 to 30 parts by weight based on 100 parts by weight of a monomer having three or more acryloyl groups in one molecule.

Such photoinitiators include wavelengths of 200 to 4
It is preferable that the compound absorbs 00 nm light and decomposes to generate a radical. Specifically, benzophenone, phenylbenzoyl carbinol, fernyl benzoyl methyl ethyl ether, 1-hydroxycyclohexyl phenyl ketone, 2,2'-dimethoxy- 2-phenylacetophenone, 2-methyl [4- (methylthio) phenyl]-
2-morpholino-1-propanone, methyl-0-benzoylbenzoate, 2,2′-diethoxyacetophenone, 2-hydroxy-2-methyl-phenylpropan-1-one, 2,4,6 trimethylbenzoylkisphine oxide, Methylphenyl 2-ethylanthraquinone, detramethylthiuram monosulfide, 3,3
Examples include acetophenone-based, benzoin-based, benzophenone-based, thioxanthone-based, and acylphosphine oxide-based photoinitiators such as', 4,4'-tetra (t-butylperoxycarbonyl) benzophenone.

The photoinitiator may be used in combination with a photoinitiator such as diethylaminomethyl methacrylate, triisopropanolamine, 4,4'-diethylaminophenone.

In the pressure-sensitive adhesive composition of the present invention, an unsaturated compound having one or two double bonds in one molecule or an oligomer of urethane acrylate or polyester acrylate can be used in a modified manner. , Silicon acrylate, fluorine-containing acrylate and the like are also possible.

In addition to the components (a), (b) and (c), the pressure-sensitive adhesive composition of the present invention may further comprise other copolymerizable monomers that impart internal cohesion. For example, vinyl acetate, vinyl propionate, butoxyethyl acrylate, acrylonitrile, styrene, cyclohexyl acrylate, cyclohexyl methacrylate and the like are added to the polymer composed of the monomers (a), (b) and (c). It is also possible.

As the ultraviolet or electron beam transmitting substrate, polyethylene film, polypropylene film, acrylic film, polyvinyl chloride film, polyester film, ethylene vinyl acetate film, fluorine film and the like can be used.

In the acrylic polymer of the first invention, since a peroxy group is pendant in the polymer, a crosslinked structure is formed by heating. The peroxy group partially reacts with a monomer having three or more acryloyl groups in one molecule, that is, a monomer having a double bond, and is effective in improving cohesiveness and curing strength before ultraviolet or electron beam curing. Act on. Further, by irradiating the pressure-sensitive adhesive with an electron beam, a double bond in the monomer reacts, a cross-linking reaction of the pressure-sensitive adhesive composition is formed, and the adhesive strength is reduced. On the other hand, in the pressure-sensitive adhesive composition according to the second invention to which the photoinitiator is added, the photoinitiator is decomposed by irradiation with ultraviolet rays to generate radicals, and reacts with the double bond of the monomer. Thus, a crosslinked structure is formed. Further, the peroxy group remaining in the acrylic polymer is decomposed by ultraviolet rays, and a cross-linking reaction of the acrylic polymer and a double bond of the monomer is formed. Bonding with the acrylic polymer occurs, and the adhesive strength of the pressure-sensitive adhesive composition decreases.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to embodiments.

[Preparation of Polymer ] Polymer 1 (P1) In a three-necked flask, 100 g of ethyl acetate, 0.05 g of azobisisobutyronitrile, normal butyl acrylate, methyl acrylate, vinyl acetate, and t-butyl peroxyaryl carbonate were prepared. Each of the polymerizable monomers was 77.
0 g, 10.0 g, 10.0 g, and 3.0 g are charged. Thereafter, a thermometer, a cooler, and a stirring blade were attached to the three-necked flask, the inside of the reaction system was maintained at 65 ° C., and a polymerization reaction was carried out for 7 hours while purging with N ₂ gas to prepare an adhesive polymer. Then, 130 g of toluene was added to obtain a final solution.
The properties of the above copolymer were transparent in appearance, solid content was 29%, and viscosity was 8,000 cps / 25 ° C. The weight average molecular weight _Mw of the copolymer was 944,000, and the number average molecular weight _Mn was 235,000.

[0024]Polymer 2 (P2) 100 g of ethyl acetate, azobisisobu in a three-necked flask
Tylonitrile 0.05 g, normal butyl acrylate
80.0 g, methyl acrylate 13.0 g, 2-hydro
2.0 g of xylethyl methacrylate, t-butylperoxide
5.0 g of xyaryl carbonate are charged. afterwards,
Put a thermometer, a cooler, and a stirring blade in this three-necked flask.
The temperature inside the reaction system is maintained at 65 ° C._TwoDo not perform gas replacement.
Then, a polymerization reaction was carried out for 7 hours to prepare an adhesive polymer.
Then, it was diluted with toluene to obtain a final solution. Above weight
The properties of the coalescence are transparent appearance, solid content 27.5%, viscosity 17
00 c.p.s / 25 ° C. In addition, the weight of this copolymer
Weight average molecular weight M_wIs 1160000, number average molecular weight M _n
Was 230,000.

Polymer 1A (P1A) As a comparative example of polymer 1, the following polymer was prepared.
In a three-necked flask, 100 g of ethyl acetate, 0.05 g of azobisisobutyronitrile, n-butyl acrylate 77
g, methyl acrylate, and 10 g of vinyl acetate. Thereafter, a thermometer, a cooler, and a stirring blade were attached to the three-necked flask, the temperature in the reaction system was maintained at 65 ° C., and a polymerization reaction was carried out for 7 hours while purging with N ₂ gas to obtain a sticky polymer. Then, it was diluted with toluene to obtain a final solution. The properties of this copolymer are transparent in appearance and viscosity is 5000 c.ps/2.
5 ° C, solid content 29.5%, weight average molecular weight _Mw is 124
The number average molecular weight _Mn was 320,000.

Polymer 3 (P3) In a three-necked flask, 100 g of ethyl acetate, 0.10 g of azobisisobutyronitrile, and n-butyl acrylate 87
g, methyl acrylate 3.5 g, acrylic acid 6.5 g,
Charge 3.0 g of t-butylperoxyaryl carbonate. Thereafter, a thermometer, a cooler, and a stirring blade were attached to the three-necked flask, and the inside of the reaction system was maintained at 60 ° C.
A final polymer solution was diluted with 7 hours the polymerization reaction after toluene while ₂ gas substitution. The properties of the above copolymer are transparent in appearance, solid content 42.0%, and viscosity 3000 c.p.
s / 25 ° C. The weight average molecular weight _Mw of the copolymer was 440000, and the number average molecular weight _Mn was 3500.
It was 0.

Polymer 3A (P3A) As a comparative example of Polymer 3, the following polymer was prepared.
A tacky polymer was prepared in exactly the same manner as in Polymer 3, except that t-butyl peroxyaryl carbonate was omitted from the monomers of Polymer 3. The properties of this copolymer were transparent in appearance, viscosity was 6600 cps / 25 ° C., and solid content was 40.3%. The weight average molecular weight _Mw of this polymer was 685000, and the number average molecular weight _Mn was 135.
000.

Table 1 shows the performance of the polymers (P1, P2, P3) of the examples and the polymers (P1A, P3A) of the comparative examples as adhesives. In this case, the polymer solution of the example and the polymer solution of the comparative example were applied so that the thickness of the adhesive layer at the time of drying was 20 to 25 μm, and dried at a temperature of 150 ° C. for 5 minutes to prepare a test piece. .

[0029]

[Table 1]

Examples 1 to 6 and Comparative Examples 1 and 2 Next, specific examples of the UV-curable pressure-sensitive adhesive composition according to the present invention will be described with reference to Examples and Comparative Examples. Tables 2 and 3 show the compositions of Examples 1 to 6 and Comparative Examples 1 and 2, respectively. The saponification values of dipentaerythritol hexaacrylate, tetramethylolmethane triacrylate and tetramethylolmethanetetraacrylate in the table are as follows:
They are 50 mgKOH / g, 485 mgKOH / g and 619 mgKOH / g, respectively.

[0031]

[Table 2]

[0032]

[Table 3]

[Preparation of Test Piece] A polyester resin (trade name: Coronate L, manufactured by Nippon Polyurethane Industry Co., Ltd.) was applied to a 125 μm-thick polyethylene terephthalate (PET) film so that the resin layer had a thickness of 1 to 3 μm. It was dried at a temperature of 130 ° C. for 30 seconds to form a primer resin layer. Then, the composition liquids of Examples 1 to 6 and Comparative Examples 1 and 2 were applied on this primer resin layer so that the cured resin composition had a thickness of 20 to 30 μm.
Dry for 5 minutes at a temperature of ° C. Thereby, a pressure-sensitive adhesive layer that is normally tacky and can be cured by ultraviolet irradiation is formed,
This sample was used as a test piece for evaluation.

[Preparation of Test Piece for Evaluation of Adhesive Strength] A 25 μm-thick polyimide film (trade name: Kapton, manufactured by Toray-Dupont) was attached to the surface of the pressure-sensitive adhesive layer of the above-mentioned test piece. The specimen was cut to prepare a test piece for evaluating adhesion.

[Measurement of Peeling Force] Initial Adhesive Force (A) One end of a PET film, a primer layer, a pressure-sensitive adhesive layer, and a polyimide film was peeled off, and a tensile tester was used for 300 minutes per minute.
Peeling was performed at 180 ° at a speed of mm, and the peeling force at that time was measured. This value was defined as the initial adhesive strength (A).

Adhesion after UV irradiation (B) The test piece (2 cm wide × 20 cm long) was irradiated with ultraviolet light from the side of the PET film to cure the pressure-sensitive adhesive layer. Similarly, the peeling force was measured using a tensile tester.

In this case, the resin was cured by using one metal halide lamp at 120 W / cm ² and height 15c.
m and an irradiation speed of 1 m / min. Under these conditions, the integrated light amount transmitted through the 125 μm PET film and irradiated on the pressure-sensitive adhesive composition was 330
It is 1.2 J / cm2 from nm to 390 nm. In addition, irradiation was similarly performed in the case of the following test pieces.

The above test piece was left at a temperature of 60 ° C. for 240 hours, and the peeling force was measured to determine the adhesive strength (C). Further, the test piece was left at a temperature of 40 ° C. and a humidity of 90% RH for 240 hours, and the peeling force was measured to determine the adhesive strength (E). Further, these test pieces are irradiated with ultraviolet rays by the method described above,
The subsequent peeling force was measured to determine the adhesive strength (D) (F)
And The stability in the bonded state was evaluated by such measurement.

A test piece was prepared by laminating release paper in place of the above-mentioned polyimide film, and was left at a temperature of 60 ° C. for 240 hours so as not to absorb light. Thereafter, the peeling force after irradiation with no ultraviolet light and the irradiation after irradiation were measured by the above-mentioned methods, and the adhesive strengths (G) and (H) were obtained. Table 4 shows the measurement results. As can be seen from Table 4,
Examples 1 to 6 using the above polymers P1, P2 and P3
Has a high adhesive strength before irradiation with ultraviolet rays, but has a low adhesive strength after irradiation.

[0040]

[Table 4]

<< Examples 7 to 16 >> In the case where the amount of the monomer having 4 and 6 double bonds in one molecule was changed by using the above-mentioned polymer 3, and the isocyanate compound (Coronate L) was used. Table 5 and Table 6 show examples in the case of crosslinking.
Shown in

[0042]

[Table 5]

[0043]

[Table 6]

As can be understood from Tables 5 and 6, the polyfunctional compound having three or more double bonds in one molecule is 35 to 150 parts by weight per 100 parts by weight of the resin of the acrylic polymer used in the present invention. By blending parts by weight, the initial adhesive strength (A) and the adhesive strength (C) in the bonded state (60 ° C., 40 ° C. × 90% RH), respectively, in the state not irradiated with ultraviolet light,
Regarding (E) and the adhesive strength (G) of product stability (60 ° C.), a value of 200 g / 2 cm or more was obtained. That is,
When the adhesive strength is 200 g / 2 cm or more, the adhesive strength is necessary and sufficient for fixing parts and bonded products.

On the other hand, by irradiating ultraviolet rays from the ultraviolet-permeable polyester film side, the photoinitiator is decomposed to generate radicals, which react with double bonds to form a crosslinked structure. Peroxy groups remaining in the polymer are decomposed by ultraviolet rays to form a crosslinked structure of the polymer and a crosslinked structure with a double bond,
This results in a bond between the polyfunctional compound and the polymer.
As a result, as understood from Tables 5 and 6, the adhesive strength of the pressure-sensitive adhesive composition is reduced, and the fixed component and the bonded product can be easily peeled without being damaged. still,
The peeling force for easily peeling such a part or the like varies depending on the physical strength of the part or the like, but is preferably 150 g / 2 cm or less from the viewpoint of workability.

Comparative Examples 3 and 4 Using Polymer 3, a test piece was prepared in the same manner as in the above example using an unsaturated monomer having one or two double bonds in one molecule. And the adhesive strengths (A) and (B) were measured. Table 7 shows the results. In this case, the unsaturated monomer having one double bond in one molecule includes M
111 was used.

Embedded image Moreover, as a compound having two double bonds in one molecule, 1,6-hexanediol diacrylate (NK ester A-HD, manufactured by Shin-Nakamura Chemical Co., Ltd.) was used. Further, based on this result, the relationship between the number of double bonds in the unsaturated monomer and the initial adhesive strength and the adhesive strength after ultraviolet curing was determined. The result is shown in FIG. As is clear from Table 7 and FIG. 1, when the number of double bonds in the unsaturated monomer is 1 to 2, the initial adhesive strength before ultraviolet irradiation is low, while the adhesive strength after ultraviolet curing is high, A decrease in peeling force due to ultraviolet irradiation as in the above embodiment cannot be expected.

[0047]

[Table 7]

Examples 17 to 26 Photoinitiators (2, 2 ')
Examples in which the concentration of (dimethoxy-2-phenylacetophenone) was changed were prepared, and the above-mentioned adhesive strengths (A) to (H) were measured. Table 8 shows the results. In this case, the concentration of the photoinitiator is represented by a weight ratio when the polyfunctional monomer is 100. That is, it is represented by (photoinitiator / polyfunctional monomer) × 100. As understood from Table 8, the initial tackiness was obtained by adding 0.1 to 28.0 parts by weight of the photoinitiator to 100 parts by weight of the unsaturated monomer having three or more acryloyl groups in one molecule. A high-pressure and stable pressure-sensitive adhesive composition can be obtained.

[0049]

[Table 8]

Examples 27 to 30 By the way, the polymer 3 contains a carboxyl group as a functional group in addition to a peroxy group. The reactive monomer of a mixture (65:35 weight ratio) of tetramethylolmethanetetraacrylate and tetramethylolmethanetriacrylate has a saponification value of 572 mg KOH / 1 kg (NK ester A-TM
M3, manufactured by Shin-Nakamura Chemical Co., Ltd.), and the saponification value of dipentaerythritol hexaacrylate (M-400, manufactured by Toagosei Co., Ltd.) is 50 mgKOH / g. Therefore, as a cross-linking agent that reacts with active hydrogen, for example, an organic metal compound containing an isocyanate group, an aziridinyl group, a methylol group, or an alkoxy group easily reacts with a carboxyl group, a hydroxyl group, or the like. Therefore, by applying the photocurable pressure-sensitive adhesive composition to an ultraviolet-permeable film and drying, the polymer and polymer, the unsaturated monomer and polymer, A bond between the body and the unsaturated monomer is formed.

As a result, when the crosslinking agent (Coronate L) was blended, the initial adhesive strength, the aging after bonding, the film stability and the ultraviolet light were evident from Examples 27 to 30 and Table 1 shown in Table 9. An excellent pressure-sensitive adhesive composition can be obtained with respect to a decrease in peeling force after irradiation.

[0052]

[Table 9]

<< Examples 31-33 >> α-photoinitiator
Table 10 shows examples using hydroxyacetophenone, α-aminoacetophenone and isopropylthioxanthone as a photoinitiator. As can be understood from Table 10, this example also shows high initial adhesive strength and stability as in the above example.

[0054]

[Table 10]

[0055]

As described above, according to the present invention, it is possible to provide a pressure-sensitive adhesive composition having a high initial adhesive strength, excellent storage stability, and good releasability after curing.
As a result, even when the adherend or the component is distorted or not smooth, the component can be securely fixed, the intrusion of acid or alkali liquid can be prevented, and the initial cohesive force is high. As a result, the pressure-sensitive adhesive protrudes and the workability of punching improves. Further, the efficiency of the work of removing and peeling after ultraviolet curing can be improved, and even if the adherend and the component are thin and weak, they can be prevented from being torn, broken or broken.

[Brief description of the drawings]

FIG. 1 is a graph showing the relationship between the number of double bonds, the initial adhesive strength, and the adhesive strength after ultraviolet curing in the adhesive compositions of Examples and Comparative Examples.

Claims (2)

[Claims] 1. A compound of the general formula With respect to 100 parts by weight of a monomer mainly composed of an acrylic ester (a) represented by the formula, a hydroxyl group copolymerizable with the acrylic ester (a),
0 to 29 parts by weight of a reactive unsaturated monomer (b) having at least one of a carboxyl group, an epoxy group, an amino group and a derivative, and an acid anhydride, a general formula: A peroxy compound (c) having a double bond
5 to 15 parts by weight, and the reactive monomer (b) and the peroxy compound (c)
Is a composition containing 0.5 to 30 parts by weight based on 100 parts by weight of the acrylic ester (a), and the acrylic polymer 100 polymerized so that the peroxy group of the peroxy compound (c) is present. Parts by weight, a monomer 3 having three or more acryloyl groups in one molecule
An adhesive composition comprising 5 to 150 parts by weight. 2. A photoinitiator is used in an amount of 0.1 to 3 based on 100 parts by weight of a monomer having three or more acryloyl groups in one molecule.
The pressure-sensitive adhesive composition according to claim 1, wherein 0 part by weight is added.