JPH0737600B2 - Curable adhesive composition and sheet or tape using the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a tacky property at the time of joining and can be temporarily adhered to an adherend, and is then cured by heating, irradiation with light, or simply by bonding to form a strong bond. The present invention relates to a curable pressure-sensitive adhesive composition suitable as a so-called adhesive and pressure-sensitive adhesive, and a pressure-sensitive adhesive sheet or tape prepared by coating or impregnating it with a substrate.

[0002]

2. Description of the Related Art Conventionally, as a curable pressure-sensitive adhesive composition, a non-reactive or reactive pressure-sensitive adhesive polymer to which a reactive oligomer or monomer is added is known (Japanese Patent Publication No. 50-28970). , Japanese Patent Publication No. 53-318
98, JP-A-53-118439, JP-B-54-28877, JP-A-60-69178, JP-B-61-18591, and JP-A-61-83.
273, JP-A-61-83274, JP-A-61-101583, JP-B-1-36513, JP-B-2-5791). However, in these compositions, when a large amount of reactive oligomer or monomer is added in order to obtain a sufficient adhesive strength after curing, the adhesive property before curing, particularly the cohesive force is lowered, and the adhesiveness from the sticking to the curing is reduced. There was a possibility that a gap or peeling might occur between the two. On the other hand, if the addition amount of the reactive oligomer or monomer is reduced in order to improve the adhesive property before curing, especially the cohesive force, the curability becomes low and the sufficient adhesive force cannot be obtained. As described above, a curable pressure-sensitive adhesive composition having sufficiently excellent adhesive properties before curing, particularly cohesive force and adhesive force after curing, has not been developed.

Therefore, the prior invention (Japanese Patent Laid-Open No. 1-188508)
JP, JP-A-1-193314, JP, JP 1-1
No. 93315), a pressure-sensitive adhesive having curability imparted to the polymer itself, which is excellent in adhesive properties before curing and adhesive force after curing, by introducing graft chains having a plurality of unsaturated groups into the polymer. I developed a composition,
There were some problems in terms of composition and physical properties.

[0004]

[Problems to be Solved by the Invention] Since the synthesis of this resin is a reaction to a polymer, the reaction rate is very slow, and if the reaction is stopped midway, the problem of odor due to unreacted raw materials and performance There was a possibility of deterioration. It was also difficult to easily and stably produce a product with a good balance of adhesive properties and adhesive strength after curing.

The present invention has improved the above-mentioned various problems in terms of synthesis and physical properties in the conventional curable pressure-sensitive adhesive composition, and has a sufficiently high curability in the adhesive property before curing and the adhesive force after curing. An adhesive composition and a sheet or tape using the same are provided.

[0006]

The present invention provides an unsaturated polyester oligomer obtained by reacting a compound (a) having a hydroxyl group, a cyclic acid anhydride (b) and an epoxide (c) having an ethylenically unsaturated group. A curable pressure-sensitive adhesive composition comprising (A), an adhesive acrylic polymer (B), and a polymerization initiator (C), and a sheet or tape using the same.

The curable resin composition of the present invention is similar to conventional ones in that it is a blend of an adhesive polymer and a reactive oligomer. However, the conventional blend type pressure-sensitive adhesive cannot be excellent because it cancels the properties of both blended as described above. On the other hand, when the polyester oligomer (A) of the present invention is used as the oligomer, the compatibility with the adhesive acrylic polymer (B) is not so good, and it is considered that the micro phase separation structure is probably taken for that reason. To be Therefore, not only is the resin hardened, but the adhesive properties before hardening, in particular the cohesive strength, which has been greatly reduced in conventional products, are rather improved. Further, by adding the polyisocyanate (D), it is possible to significantly improve the cohesive force without impairing the curability.

In the curable resin composition of the present invention, the compound (a) having a hydroxyl group is an aliphatic compound such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, pentanol or hexanol. Saturated unsaturated alcohols such as allyl alcohol, crotyl alcohol, propargyl alcohol, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate,
3-Hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, N-methylol acrylamide or other (meth) acrylate having a hydroxyl group or (meth) acrylamide, alicyclic alcohol such as cyclopentanol or cyclohexanol ，
Aromatic alcohols such as benzyl alcohol and cinnamyl alcohol, Heterocyclic alcohols such as furfuryl alcohol and tetrahydrofurfuryl alcohol, ethylene glycol, propylene glycol, 1,4-butylene glycol, butenediol, hexanediol, cyclohexanediol, bisphenol A Compounds having alcoholic or phenolic hydroxyl groups such as diols such as diethylene glycol, glycerin, triols such as trimethylolpropane, phenols such as phenol, o-cresol, m-cresol and p-cresol.

However, among these, the above-mentioned diol and 2
-Hydroxy-n-butyric acid, 3-hydroxy-n-butyric acid,
Compounds having both a carboxyl group and a hydroxyl group such as p-hydroxybenzoic acid, hydroxypivalic acid, salicylic acid, vanillic acid and 12-hydroxystearic acid, or ethanolamine, 1-amino-2-propanol, o-aminophenol, m- Aminophenol, p
Compounds having two or more functional groups are preferred, such as compounds having an amino group and a hydroxyl group at the same time, such as aminophenol.

In the curable resin composition of the present invention, the cyclic acid anhydride (b) is an intramolecular anhydride of a polycarboxylic acid, and is a saturated or unsaturated aliphatic polycarboxylic acid anhydride or alicyclic ring. Formula polyvalent carboxylic acid anhydride, aromatic polyvalent carboxylic acid anhydride, etc., or those partially substituted with saturated or unsaturated hydrocarbon groups, aromatic ring groups, halogen atoms, heterocyclic groups, etc. Yes, as specific examples of these,
Succinic anhydride, phthalic anhydride, maleic anhydride, itaconic anhydride, glutaric anhydride, dodecenyl succinic anhydride,
Chlorendec anhydride, pyromellitic anhydride, trimellitic anhydride, cyclopentanetetracarboxylic dianhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, tetramethylene maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride acid,
Endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, 5- (2,5-
Dioxotetrahydroxyfuryl) -3-methyl-3-
Cyclohexene-1,2-dicarboxylic acid anhydride, methyl nadic acid anhydride, benzophenone tetracarboxylic acid anhydride, glycerol tris (anhydro trimellitate), ethylene glycol bis (anhydro trimellitate) and the like are listed. Among these, it is preferable to use an anhydride of dicarboxylic acid or tricarboxylic acid that does not form a crosslinked structure.

In the curable resin composition of the present invention, as the epoxide (c) having an ethylenically unsaturated group, glycidyl (meth) acrylate, glycidyl cinnamate, allyl glycidyl ether, vinylcyclohexene monoepoxide, 1,3- Butadiene monoepoxide and the like may be substituted with a saturated or unsaturated hydrocarbon group, aromatic ring group, halogen atom, heterocyclic group or the like.

The compound (a) having a hydroxyl group, the cyclic acid anhydride (b) and the epoxide (c) are reacted to obtain a polyester oligomer (A) having an ethylenically unsaturated group. The reaction is carried out in the presence or absence of a suitable solvent with a tertiary amine such as N, N-dimethylbenzylamine, triethylamine, tributylamine, N, N-diethylaniline or N, N-dimethylaniline, if necessary. And a radical polymerization inhibitor such as hydroquinone, hydroquinone monomethyl ether, tert-butyl catechol, p-benzoquinone or the like is added to protect the ethylenically unsaturated group.

In the reaction, the hydroxyl group of the compound (a) having a hydroxyl group and the acid anhydride group of the cyclic acid anhydride (b) react preferentially first, and then the carboxyl group generated by this reaction and the epoxide (c). 2) reacts with the epoxy group to produce a secondary hydroxyl group. Furthermore, the generated hydroxyl group and the acid anhydride group of the cyclic acid anhydride (b) react with each other.
The same reaction as described above can be sequentially carried out.

In this reaction, the cyclic acid anhydride (b) reacted with the amount of the compound (a) having a hydroxyl group.
By adjusting the amounts of epoxide (c) and epoxide (c), it is possible to prepare a polyester oligomer (A) having a desired number of ethylenically unsaturated groups and having a desired number of ethylenically unsaturated groups terminated with a compound (a) having a hydroxyl group. it can. When the cyclic acid anhydride (b) is a dicarboxylic acid anhydride, the proportion of each compound is 1 to 20 mol of the cyclic acid anhydride (b) to 1 mol of the compound (a) having a hydroxyl group, and It is preferable that the epoxide (c) is reacted in a proportion of 1 to 20 mol, and the cyclic acid anhydride (b) and the epoxide (c) are reacted in a substantially equimolar ratio. When the cyclic acid anhydride (b) is a tricarboxylic acid, a compound (a) having a hydroxyl group
The ratio of 1 to 10 moles of cyclic acid anhydride (b) and 1 to 20 moles of epoxide (c) relative to 1 mole, and about 1 mole of epoxide (c) to 1 mole of cyclic acid anhydride (b)
It is preferable to react at a ratio of 2 mol. When the amount of the cyclic acid anhydride (b) or epoxide (c) reacted with 1 mol of the compound (a) having a hydroxyl group is less than 1 mol, the obtained polyester oligomer (A) is obtained.
Has a low molecular weight and the compound (a) having a hydroxyl group remains, so that the required characteristics cannot be obtained. On the other hand, when the amount of the cyclic acid anhydride (b) or the epoxide (c) exceeds 20 mol, it becomes difficult to control the reaction or the molecular weight becomes too high, so that the necessary properties tend not to be obtained. There is.

In the curable resin composition of the present invention, the tacky acrylic polymer (B) means a hydroxyl group, a tertiary amino group,
It has a functional group such as a carboxyl group, an amide group, an N-substituted amide group, and a nitrile group, and is generally used as an acrylic resin for pressure-sensitive adhesives. Also,
Even if the polymer alone is inferior in tackiness, by adding the polyester oligomer (A) and other resins,
A polymer showing good adhesive properties can be used as the polymer (B) of the present invention. The acrylic polymer having these functional groups includes one or several kinds of monomers having a hydroxyl group, a tertiary amino group, a carboxyl group, an amide group, an N-substituted amide group, a nitrile group, an alkyl (meth) acrylate, Examples thereof include copolymers with monomers such as vinyl acetate, vinyl propionate, vinyl ether and styrene.

Examples of the monomer having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate and N-methylolacrylamide. , Allyl alcohol and the like, and examples of the monomer having a tertiary amino group include dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylamide and the like. Examples of the monomer having a carboxyl group include acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid and citraconic acid. Examples of the monomer having an amide group or an N-substituted amide group include acrylamide, methacrylamide, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N-methoxymethyl (meth) acrylamide,
Examples include N-ethoxymethyl (meth) acrylamide, N-propoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, N-tert-butylacrylamide, N-octylacrylamide, diacetone acrylamide. Examples of the monomer having a nitrile group include acrylonitrile, methacrylonitrile, crotononitrile, and fumaronitrile. Further, as the alkyl (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate,
There are alkyl (meth) acrylates such as butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate and octyl (meth) acrylate. In addition, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, etc., and alkyl (meth) acrylate in which the alkyl group is substituted with an aromatic ring group, a heterocyclic group, a halogen atom, etc. The monomers used in the synthesis of acrylic polymers can also be used in the synthesis of the polymers of the invention.

The reaction is an ordinary radical polymerization, and there is no limitation on the reaction method, and it can be carried out by a known polymerization method such as solution polymerization, bulk polymerization, emulsion polymerization, etc., but it is easy to control the reaction. Solution polymerization is preferred because it can be directly transferred to the next operation. Any solvent may be used as long as it can dissolve the resin of the present invention, such as methyl ethyl ketone, methyl isobutyl ketone, toluene, cellosolve, ethyl acetate and butyl acetate, and may be used alone or as a mixture of a plurality of solvents. Known polymerization initiators used in the polymerization reaction include organic peroxides such as benzoyl peroxide, acetyl peroxide, methyl ethyl ketone peroxide and lauroyl peroxide, and azo initiators such as azobisisobutyronitrile. Anything can be used, and there is no particular limitation.

A curable adhesive resin can be obtained by mixing the unsaturated polyester oligomer (A) obtained by each reaction with the adhesive acrylic polymer (B). It is sufficient to stir the mixture at room temperature until it becomes apparently homogeneous, but in order to further enhance the state of mutual mixing, heating and stirring may be performed at a temperature not higher than the boiling point of the solvent.

In the present invention, since the epoxide (c) having an ethylenically unsaturated group is used, the polyester oligomer (A) has an unsaturated group, and thus the electron beam curing and the appropriate polymerization initiator (C) are combined. Heat curing, anaerobic curing, in combination with
It can be easily solidified by a curing method such as light curing.

As the polymerization initiator (C) used in the case of heat curing or anaerobic curing, di-alkyl peroxides such as di-tert-butyl peroxide, tert-butyl cumyl peroxide, dicumyl peroxide, and acetyl peroxide. Diacyl peroxides such as oxide, lauroyl peroxide and benzoyl peroxide, methyl ethyl ketone peroxide, cyclohexanone peroxide, 3,3,5-trimethyl cyclohexanone peroxide, methyl cyclohexanone peroxide and other ketone peroxides, 1,
Peroxyketals such as 1-bis (tert-butylperoxy) cyclohexane, tert-butylhydroperoxide, cumene hydroperoxide, 1,
Hydroperoxides such as 1,3,3-tetramethylbutyl hydroperoxide, p-menthane hydroperoxide, diisopropylbenzene hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, tert-butyl Organic peroxides such as peroxyesters such as peroxyacetate, tert-butylperoxy-2-ethylhexanoate and tert-butylperoxybenzoate, azo such as azobisisobutyronitrile and azobisvaleronitrile There is no particular limitation as long as it is a known compound such as a compound.
The polymerization initiator (C) is generally 0.1 to 15 parts by weight, preferably 0.5 to 100 parts by weight of the pressure-sensitive adhesive composition of the present invention.
It is used in a proportion of up to 5 parts by weight.

When an organic peroxide having a low radical generation rate is used, N, N-dimethylbenzylamine, triethylamine, tributylamine, N, N
-Diethylaniline, N, N-dimethylaniline, N-
Tertiary amines such as phenyldiethanolamine, N-phenyldiisopropanolamine, dimethyl-p-toluidine, triethanolamine, 4-phenylmorpholine, lithium, calcium, strontium, barium, cerium, zirconium, vanadium, molybdenum, manganese, iron , Cobalt, nickel, copper, zinc, tin, lead and other metal laurate, naphthenate, octylate, oleate, octenoate and other fatty acid salts, rosin and other resin salts, acetylacetate One or more metal compounds selected from chelate compounds such as nate complex salts may be used as an accelerator. In particular, in the case of anaerobic curing, it is preferable to use either a tertiary amine or a metal compound or both as an accelerator together with an organic peroxide. Of these promoters, tertiary amines are usually organic peroxides.
The metal compound is 0.01 to 10 parts by weight based on 100 parts by weight with respect to 100 parts by weight of the organic peroxide.
Used in proportions by weight.

As the polymerization initiator (C) used in the case of photocuring, benzoin, benzoin methyl ether, benzoin ethyl ether, o-benzoylbenzoic acid methyl-p-benzoin ethyl ether, benzoin isopropyl ether, α-methylbenzoin. Such as benzoins, dimethylbenzyl ketal, trichloroacetophenone, acetophenones such as 2,2-diethoxyacetophenone, 2-hydroxy-2-methylpropiophenone, 2-hydroxy-4'-isopropyl-
Propiophenones such as 2-methylpropiophenone, α-acyloxime ester, benzophenone, methylbenzophenone, p-chlorobenzophenone, benzophenones such as p-dimethylaminobenzophenone,
In addition to thioxanthones such as 2-chlorothioxanthone, 2-ethylthioxanthone, and 2-isopropylthioxanthone, benzyl, dibenzosuberone, etc., edited by Kiyomi Kato: "UV / EB Curing Handbook-Raw Materials-" (1
67-73 pages, published by Kobunshi Kogyokai, December 985, or "Handbook of Crosslinking Agents" edited by Fuzo Yamashita and Tosuke Kaneko (October 1981, Taiseisha), pages 582-593. There is something. These polymerization initiators (C) are
You may use it with a promoter.

Examples of such accelerators include 4,4'-bis (diethylamino) benzophenone, ethyl N-dimethylaminobenzoate, dimethylethanolamine and glycine, as well as Kiyomi Kato, ed., Supra, 67-. Those described on page 73 can be used. When using light having a relatively long wavelength such as ultraviolet rays or visible light, it is preferable to use a polymerization initiator and, if necessary, an accelerator, from the viewpoint of curing efficiency. The polymerization initiator (C) is
It is usually 0. 0 with respect to 100 parts by weight of the pressure-sensitive adhesive composition of the present invention.
It is used in a proportion of 05 to 20 parts, preferably 0.5 to 10 parts.

The above-mentioned polymerization initiator (C) and accelerator can be used in the form of microcapsules. When a pressure-sensitive adhesive composition or a product such as a tape or sheet made using the same is left for a long time before being used, it can be kept stable until it is used by this method. Particularly in the case of anaerobic curing, it is possible to greatly improve the storage stability by microcapsulating one or a plurality of the polymerization initiators and accelerators used. There is no particular limitation on the method of microencapsulating the above-mentioned polymerization initiator and accelerator, and there is no particular limitation.
6, Japanese Patent Publication No. 42-771, Japanese Patent Publication No. 42-2
882, Japanese Examined Patent Publication No. 42-2883, Japanese Patent Laid-Open No. 5
6-115371, JP-A-60-60173, and other interfacial polymerization methods, JP-B-36-9168.
Publication, USP 3427250 Publication, BP 12364
In situ polymerization method described in Japanese Patent Publication No. 98, U.
In-liquid curing coating method described in SP 3787327, USP 3551346, USP 3574133, etc., USP 2800457, USP 28
00458 publication, USP3531418 publication, US
Coacervation method (phase separation method) described in P35777515 and BP1117178, USP
There are an interface precipitation method described in US Pat. No. 3,523,906 and USP3660304, and a spray dry method described in USP3830750. Among these methods, polyurea, which can control the thickness of the microcapsule wall freely, can make the thickness of the microcapsule wall uniform, and increase the strength of the microcapsule wall, can be used as the microcapsule wall. Interfacial polymerization method,
Microencapsulation is preferably carried out by the complex coacervation method using gelatin and acacia as microcapsule walls. The detailed method of microencapsulation is described in detail in the above-mentioned patent and JP-A-1-193314.

In order to improve the adhesive properties before curing, in particular to enhance the cohesive strength, polyisocyanate (D) is further added to the adhesive composition of the present invention to partially crosslink the adhesive acrylic polymer (B). Can be made. Such polyisocyanates include tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, m-xylene diisocyanate, p-xylene diisocyanate, 1,5-naphthalene diisocyanate, isophorone diisocyanate, lysine diisocyanate, hydrogenated 4, There are diisocyanates such as 4'-diphenylmethane diisocyanate and hydrogenated tolylene diisocyanate, or both ends isocyanate adducts of these with glycols or diamines, or a mixture thereof, and if necessary, triphenylmethane triisocyanate, poly Tri- or higher functional polyisocyanates such as methylene polyphenyl isocyanate can also be used by mixing with diisocyanates. Wear.

In order to adjust the adhesive property before curing and the adhesive force after curing, a polyester oligomer synthesized by using an epoxide having no ethylenically unsaturated group, or an ethylenically unsaturated group used in the present invention is used. An oligomer synthesized using both the epoxide (c) and the epoxide having no unsaturated group can be used as the polyester oligomer (A) of the present invention. However, when an oligomer having no ethylenically unsaturated group is used, it must be used in combination with an oligomer having an unsaturated group. Examples of epoxides having no ethylenically unsaturated group include epichlorohydrin, phenylglycidyl ether, styrene oxide, cyclohexene oxide, and butene oxide.

In order to further strengthen the adhesive strength after curing, the pressure-sensitive adhesive composition of the present invention further comprises an ethylenic group such as a (meth) acryloyl group other than the unsaturated polyester oligomer (A) used in the present invention. A monomer or oligomer having an unsaturated group can be added. Examples of such monomers or oligomers include styrene, alkyl (meth) acrylate, (meth) acrylic acid, polyhydric alcohol poly (meth) acrylate, epoxy poly (meth) acrylate, oligoester poly (meth) acrylate, polyurethane poly ( (Meth) acrylate, diallyl phthalate, diallyl isophthalate and the like. The amount of these monomers or oligomers used is 60% by weight or less based on the total solid content of the pressure-sensitive adhesive composition of the present invention. 60
If the content exceeds 10% by weight, the adhesive properties before curing, especially the cohesive strength, will be significantly deteriorated.

The pressure-sensitive adhesive composition of the present invention contains pigments, dyes, inorganic fillers, organic solvents, metal powders such as silver powder, copper powder, nickel powder, and the like, if necessary, as long as the performance thereof is not impaired.
Carbon black, graphite, tackifiers such as xylene resin and rosin resin, and silane coupling agents can be added.

The pressure-sensitive adhesive composition of the present invention is used for peeling paper or cloth treated with silicone, paper or cloth processed with a low-adhesive resin such as polyethylene terephthalate film laminated paper, metal foil or plastic film. It is coated on a highly resistant film, sheet or tape, dried to remove the organic solvent if necessary, and cut if necessary to form a double-sided or single-sided adhesive sheet or tape. In addition, for reinforcement and impact relaxation, it is lined with non-woven fabric such as rayon and nylon, cloth such as gauze, foam such as urethane and acrylic, and these cloths and foams are used as core materials. The pressure-sensitive adhesive composition of the present invention can also be used by coating or impregnating it. If the tape or sheet base material, core material, etc. used here remains in the adhesive part even after being used together with the adhesive composition, they are significantly deteriorated by a treatment for curing such as heating or light irradiation. It should be such that it does not significantly interfere with curing.

The double-sided pressure-sensitive adhesive sheet or tape thus obtained is sandwiched between two adherends of the same kind or different kinds, temporarily adhered due to its good adhesiveness, and then treated according to each curing method. By doing so, the pressure-sensitive adhesive composition is cured and the adherends can be firmly adhered to each other. In addition, a single-sided adhesive sheet or tape is temporarily adhered to an adherend due to its good adhesiveness, and then, if necessary, the sheet or tape which is the base material is peeled off, and the adhesive surface is formed by another adherend. Is further temporarily adhered, and the pressure-sensitive adhesive composition is cured by performing a treatment according to each curing method.
It can be firmly adhered to an adherend.

When the polymerization initiator, the accelerator, etc. are microencapsulated, the microcapsules are broken by applying a force such as a pressure of a pressure roll before or after temporarily adhering to the adherend. Alternatively, depending on the properties of the microcapsules, it is necessary to destroy the capsules by applying heat or irradiating light such as ultraviolet rays. However, it is not necessary to break the sustained-release microcapsules.

In the case of anaerobic curing, after temporarily adhering to an adherend, curing is started soon by the action of a polymerization initiator or the like, and practical strength is reached within a few hours to a week. In the case of heat curing, it is usually 80-
Heating is carried out at 150 ° C. for about 3 to 20 minutes, and at 80 to 150 ° C. for about 0.5 seconds to 5 minutes in contact heating such as hot pressing. In the case of photocuring, particularly in the case of a double-sided pressure-sensitive adhesive tape or sheet, at least one has a light-transmitting property and can be adhered by irradiating light from the side of the light-transmitting adherend. . The single-sided pressure-sensitive adhesive sheet or tape can be adhered by irradiating light from the light-transmitting tape or sheet base material or the light-transmitting adherend side.

In the present invention, as the light, visible light from a sun or a fluorescent lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halide lamp, a carbon arc lamp, an ultraviolet ray from a xenon lamp, or cobalt 60 is used. In addition to γ-rays as a source or X-rays as an X-ray generator, an electron beam as an electron beam accelerator is also included. Among these, in practice, it is preferable to use visible light, ultraviolet light, or an electron beam, particularly visible light or ultraviolet light having a wavelength of 200 to 800 nm. When ultraviolet rays are used as the light, it is preferable to use the polymerization initiator (C) and, if necessary, an accelerator from the viewpoint of curing efficiency. Output of radiation source, distance from radiation source, irradiation area, type and amount of resin, polymerization initiator and accelerator used, thickness of adhesive composition layer, type and thickness of adherend or tape or sheet substrate The amount of irradiation is usually 0.5 to 50 Mrad for electron beams and 20 to 5 for ultraviolet rays.
The irradiation time is about 3,000 mJ / cm ^{2 and} about 0.3 to 30 seconds.

[0034]

EXAMPLES The present invention will be described below with reference to examples. In the examples, “part” means “part by weight” and “%” means “% by weight”.

Synthesis of polyester oligomer

Oligomer 1 Ethylene glycol 2.0 parts Hexahydrophthalic anhydride 51.0 parts Glycidyl methacrylate 47.0 parts N, N-Dimethylbenzylamine 0.9 parts Hydroquinone 0.2 parts Ethyl acetate 25.0 parts The above composition Were mixed and reacted at 80 ° C. for 10 hours in an air atmosphere, and after cooling, 125 parts of ethyl acetate was added to obtain a solution of polyester oligomer 1 (solid content 40%).

Oligomer 2 Ethylene glycol 3.4 parts Hexahydrophthalic anhydride 50.3 parts Glycidyl methacrylate 46.3 parts N, N-Dimethylbenzylamine 0.9 parts Hydroquinone 0.2 parts Ethyl acetate 25.0 parts The above composition Were mixed and reacted in an air atmosphere at 80 ° C. for 10 hours, and after cooling, 125 parts of ethyl acetate was added to obtain a solution of polyester oligomer 2 (solid content: 40%).

Oligomer 3 Ethylene glycol 2.5 parts Succinic anhydride 40.3 parts Glycidyl methacrylate 57.2 parts N, N-Dimethylbenzylamine 1.1 parts Hydroquinone 0.2 parts Ethyl acetate 25.0 parts After mixing and reacting in an air atmosphere at 80 ° C. for 10 hours, after cooling, 125 parts of ethyl acetate was added to obtain a solution of polyester oligomer 3 (solid content 40%).

Oligomer 4 p-Hydroxybenzoic acid 4.5 parts Hexahydrophthalic anhydride 49.7 parts Glycidyl methacrylate 45.8 parts N, N-Dimethylbenzylamine 0.9 parts Hydroquinone 0.2 parts Ethyl acetate 25.0 parts The above compositions were mixed and reacted at 80 ° C. for 10 hours in an air atmosphere, and after cooling, 125 parts of ethyl acetate was added to obtain a solution of polyester oligomer 4 (solid content 40%).

Oligomer 5 1-Amino-2-propanol 2.5 parts Hexahydrophthalic anhydride 50.7 parts Glycidyl methacrylate 46.8 parts N, N-Dimethylbenzylamine 0.9 parts Hydroquinone 0.2 parts Ethyl acetate 25. 0 part The above composition was mixed and allowed to react at 80 ° C. for 10 hours in an air atmosphere. After cooling, 125 parts of ethyl acetate was added to obtain a solution of polyester oligomer 5 (solid content 40%).

Oligomer 6 p-Hydroxybenzoic acid 4.3 parts Hexahydrophthalic anhydride 48.5 parts Phenylglycidyl ether 47.2 parts N, N-Dimethylbenzylamine 0.9 parts Ethyl acetate 25.0 parts

The above composition was mixed, and the mixture was mixed in an air atmosphere at 80
After reacting for 10 hours at ℃, after cooling, 125 parts of ethyl acetate was added to the solution of polyester oligomer 6 (solid content 40
%) Was obtained.

Synthesis of acrylic polymer

Polymer 1 Butyl acrylate 88.2 parts Vinyl acetate 5.6 parts 2-Hydroxyethyl methacrylate 6.2 parts Azobisisobutyronitrile 0.2 parts Ethyl acetate 150.0 parts The above composition heated to 80 ° C. 125 parts of the mixture having the same composition as above was added dropwise to 125 parts of the mixture.
The mixture was heated under reflux for hours and cooled to obtain a solution of acrylic polymer 1 (solid content 40%).

Polymer 2 Butyl acrylate 93.5 parts Acrylic acid 1.4 parts 2-Hydroxyethyl methacrylate 5.1 parts Azobisisobutyronitrile 0.2 parts Ethyl acetate 150.0 parts The above composition heated to 80 ° C. 125 parts of the mixture having the same composition as above was added dropwise to 125 parts of the mixture.
The mixture was heated under reflux for hours and cooled to obtain a solution of acrylic polymer 2 (solid content: 40%).

Polymer 3 Butyl acrylate 92.0 parts Acrylamide 2.8 parts 2-Hydroxyethyl methacrylate 5.2 parts Azobisisobutyronitrile 0.2 parts Ethyl acetate 150.0 parts

Mixture 12 of the above composition heated to 80 ° C.
To 5 parts, 125 parts of the above-mentioned mixture having the same composition was added dropwise, and after completion of the addition, the mixture was heated under reflux for 12 hours and cooled to obtain a solution of acrylic polymer 3 (solid content 40%).

[0048]

Example 1 41.9 parts of a solution of an oligomer 1 and 58.1 parts of a solution of a polymer 1 were thoroughly mixed to obtain 10 parts of this resin solution.
0.4 part of benzoyl peroxide was uniformly mixed with 0 part to obtain a curable pressure-sensitive adhesive composition. The obtained curable pressure-sensitive adhesive composition was applied onto a silicone-treated polyethylene terephthalate film so that the thickness after drying was 30 μm, and dried at 60 ° C. for 3 minutes to obtain a pressure-sensitive adhesive sheet. Further, 0.2 part of tolylene diisocyanate was further added to the resin mixture having the above composition to obtain a pressure sensitive adhesive sheet, which was aged at 50 ° C. for 3 days.

Table 1 shows the measurement results of the adhesive properties (peeling adhesive strength, tack, holding power) before curing and the shear adhesive strength after curing of the obtained adhesive sheet. Curing was performed by heating in an oven at 130 ° C for 10 minutes. The measurement was performed as follows.

(1) Peeling adhesive strength before curing A polyethylene terephthalate sheet having a thickness of 50 μm was adhered to the adhesive surface of the obtained adhesive sheet, cut into a width of 25 mm, and then the polyethylene terephthalate film was peeled off to form. Adhesive surface is adhered to a # 280 sandpaper-polished stainless steel plate (SUS304), left for 30 minutes, and then peeled at 180 degrees at a peeling speed of 300 mm / min under conditions of 25 ° C and 65% relative humidity. Was measured.

(2) Tack before curing The obtained adhesive sheet was set on a slope having an inclination angle of 30 degrees, and the running distance was 10c under conditions of 25 ° C and relative humidity of 65%.
Roll a stainless steel ball at m and sticky surface 1
The number of the highest ball that stopped within 0 cm was measured. The number of the ball is represented by 32 times as many as 31 kinds of "name of ball" from 1/16 to 1.

(3) Holding power before curing A polyethylene terephthalate sheet having a thickness of 50 μm is attached to the adhesive surface of the obtained adhesive sheet, cut into a size of 25 mm in width and 100 mm in length, and then a polyethylene terephthalate film. The 25 mm wide and 25 mm wide part of the resulting adhesive surface was affixed to a stainless steel plate (SUS304) polished with sandpaper # 280, and the adhesive sheet was a stainless steel plate at 40 ° C and a load of 1 kg. The time (seconds) until it fell further was measured.

(4) Shear adhesive strength after curing Adhesion of the obtained adhesive sheet cut to 10 mm in length and 10 mm in width at one end of each of two aluminum plates having a length of 50 mm, a width of 10 mm and a thickness of 0.5 mm. Attach the surface, peel off the polyethylene terephthalate film,
The resulting adhesive surfaces were attached so that they would overlap each other, and the adhesive was cured by a predetermined curing method, and then the shear strength was measured at a pulling rate of 5 mm / min under the conditions of 25 ° C. and relative humidity of 65%.

[0054]

Example 2 (Preparation of Microencapsulated Benzoyl Peroxide) While keeping 1 part of polyvinyl alcohol and 100 parts of water at 30 ° C. and stirring with a stirring blade rotating at a speed of 225 rpm, benzoyl peroxide was added to the mixture. A solution prepared by dissolving 5 parts of oxide and 5 parts of tolylene diisocyanate in 10 parts of xylene was added and dispersed, and 5 minutes later, 1 part of tetraethylenepentamine was added, and then stirring was continued for 2 hours to give tolylene diisocyanate and tetraethylene. A dispersion liquid of benzoyl peroxide microcapsules having a wall formed by the reaction of pentamine, polyvinyl alcohol and water was obtained. Obtained microcapsule dispersion 122
To 2 parts, glutaraldehyde is added 2 parts and stirred for 2 hours, then, 2 parts of N- (2-aminoethyl) -γ-aminopropyltrimethoxysilane is added, and the pH of the dispersion becomes about 11. Thus, ammonia water was added, and the mixture was further stirred for 6 hours, then the microcapsules were separated by filtration, washed with ethanol, and dried with warm air at 50 ° C to obtain microencapsulated benzoyl peroxide. The obtained microcapsules contained 20% of benzoyl peroxide.
%, The average particle size of the microcapsules was 40 μm.

45.8 parts of the solution of the oligomer 2 and 54.2 parts of the solution of the polymer 2 were thoroughly mixed, and the resin solution 10
10 parts of microencapsulated benzoyl peroxide, 0.1 part of cobalt naphthenate, 0.5 part of dimethyl-p-toluidine, and 0.1 part of tolylene diisocyanate were uniformly mixed with 0 part of 0 part to give a curable adhesive. An agent composition was obtained. The obtained curable pressure-sensitive adhesive composition was processed in the same manner as in Example 1 to obtain a pressure-sensitive adhesive sheet. The adhesive property before curing was measured in the same manner as in Example 1 while taking care not to break the microcapsules. Further, after laminating the aluminum plates in the same manner as in Example 1, 10 Kg / cm ² was applied with a pressure roll.
After pressurizing, the mixture was left at room temperature for 1 week to be sufficiently cured, and the shear adhesive force was measured under the same conditions as in Example 1. Furthermore, the same measurement was carried out two months after the production of the adhesive sheet. The above measurement results are shown in Table 1.

[0056]

Example 3 22.9 parts of the solution of the oligomer 3 and 77.1 parts of the solution of the polymer 3 were thoroughly mixed, and the resin solution 10
0.4 part of 2-hydroxy-2-methylpropiophenone and 0.1 part of tolylene diisocyanate were uniformly mixed with 0 part to obtain a curable pressure-sensitive adhesive composition. The obtained curable pressure-sensitive adhesive composition was processed in the same manner as in Example 1 to obtain a pressure-sensitive adhesive sheet. The adhesive properties of the obtained adhesive sheet before curing and the shear adhesive strength after curing were measured. The shear adhesive strength was measured by using an acrylic plate having a length of 50 mm, a width of 10 mm and a thickness of 1.0 mm instead of the aluminum plate. Curing was performed by irradiating with ultraviolet light for 15 seconds at a distance of 15 cm under a 2 kW high pressure mercury lamp. The above measurement results are shown in Table 1.

[0057]

[Example 4] 38.0 parts of the solution of oligomer 4 and 62.0 parts of the solution of polymer 2 were thoroughly mixed to obtain 10 parts of this resin solution.
A uniform mixture of 0.4 part of benzoyl peroxide and 0.2 part of tolylene diisocyanate per 0 part, 1 part of benzoyl peroxide, 0.1 part of cobalt naphthenate, 0.5 part of 4-phenylmorpholine and A uniform mixture of 0.2 parts of tolylene diisocyanate, 2-hydroxy-2-methylpropiophenone 0.
Three types of curable pressure-sensitive adhesive compositions were obtained by uniformly mixing 4 parts and 0.2 part of tolylene diisocyanate. The three types of curable pressure-sensitive adhesive compositions obtained were processed in the same manner as in Example 1 to obtain pressure-sensitive adhesive sheets. About the obtained adhesive sheet,
The adhesive properties before curing and the shear adhesive strength after curing were measured, respectively. Curing was performed by thermosetting, anaerobic curing, and photocuring, respectively. Use a hot press for heating, 130 ℃, 50Kg / c
m ² for 10 seconds. Anaerobic curing and photocuring were performed in the same manner as in Examples 2 and 3. The above measurement results are shown in Table 1.

A pressure-sensitive adhesive sheet was prepared without adding an initiator or the like to the above resin solution, and a 50 μm polyethylene terephthalate film and a stainless steel plate were prepared in the same manner as in the measurement of the holding power before curing. Were laminated with an overlap width of 5 mm, and the adhesive strength of the polyethylene terephthalate film was measured by irradiating with a 5 Mrad electron beam from the side of the polyethylene terephthalate film using an electro-curtain type electron beam irradiator to cure the polyethylene terephthalate film. Broke.

[0059]

Example 5 26.7 parts of the solution of the oligomer 5 and 73.3 parts of the solution of the polymer 3 were mixed thoroughly, and the resin solution 10
0.4 part of tert-butylperoxy-2-ethylhexanoate and 0.2 part of tolylene diisocyanate were uniformly mixed with 0 part to obtain a curable pressure-sensitive adhesive composition. An adhesive sheet was obtained from the obtained curable adhesive composition in the same manner as in Example 1, and the adhesive property before curing and the shear adhesive strength after curing were measured. Curing was carried out by heat curing as in Example 1. The above measurement results are shown in Table 1.

[0060]

Example 6 21.2 parts of a solution of oligomer 4, 21.7 parts of a solution of oligomer 6, and 57.1 parts of a solution of polymer 3 were mixed sufficiently, and 100 parts of this resin solution was mixed with 0.1 part of benzoyl peroxide. 4 parts were mixed uniformly and an adhesive sheet was obtained in the same manner as in Example 1. Further, 0.1 part of tolylene diisocyanate was further uniformly mixed with the mixture having the above composition to obtain a curable pressure-sensitive adhesive composition. An adhesive sheet was obtained in the same manner as in Example 1 using the obtained curable adhesive composition. For each of the obtained pressure-sensitive adhesive sheets, the adhesive property before curing and the shear adhesive force after curing were measured. Curing was performed in the same manner as the heat curing of Example 4. The above measurement results are shown in Table 1.

[0061]

[Table 1]

[0062]

As shown in the table, the pressure-sensitive adhesive composition of the present invention has a peel adhesive strength before curing of 1500 g / 25 mm or more, a tack of 7 or more, and a holding power of 1000 without adding polyisocyanate. More than a second. Furthermore shear adhesive strength after curing heat, in the case of anaerobic curing 30 Kg / cm ² or more, in the case of photocuring becomes 25 Kg / cm ² or more, adhesion properties before curing, it is excellent in both adhesive strength after curing .

Further, as compared with a conventional pressure-sensitive adhesive composition in which an unsaturated group is introduced into a polymer, it is superior in terms of easiness of reaction and reduction of odor due to reaction residues, and has properties as a curable pressure-sensitive adhesive. Not inferior to conventional ones. further,
Add an appropriate amount of polyisocyanate to improve cohesive strength and keep retention force even after 24 hours without deteriorating peel adhesive strength before tacking, tack, and shear adhesive strength after curing. You can

As described above, according to the present invention, the adhesiveness is high at the time of joining, shows a strong adhesive force after curing, has a good balance between the adhesive property before curing and the adhesive force after curing, and the curing is less odorous. -Type pressure-sensitive adhesive composition can now be obtained. In addition, since the sheet and tape using this can be temporarily adhered to the adherend, mechanical temporary fixing is unnecessary,
After curing, it reaches the strength of adhesives and can be used for various purposes.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C09J 7/02 JKE 133/04 JDD 175/04 JFC JFE // C08G 63/58 NPH

Claims (3)

[Claims] 1. An unsaturated polyester oligomer (A) obtained by reacting a compound (a) having a hydroxyl group, a cyclic acid anhydride (b) and an epoxide (c) having an ethylenically unsaturated group, an adhesive acrylic polymer. A curable pressure-sensitive adhesive composition comprising (B) and a polymerization initiator (C). 2. An unsaturated polyester oligomer (A),
The curable pressure-sensitive adhesive composition according to claim 1, which contains a polyisocyanate (D) in addition to the pressure-sensitive acrylic polymer (B) and the polymerization initiator (C). 3. A pressure-sensitive adhesive sheet or tape obtained by coating or impregnating a base material with the curable resin composition according to claim 1 or 2.