TW201300492A - Removable adhesive tape and manufacturing method thereof - Google Patents

Abstract

Provided is a removable adhesive tape which has with excellent heat resistance and little increase in adhesive force during removal, and which leaves no adhesive residue or contamination on the adherend. This removable adhesive tape is formed from a heat-resistant film substrate and a cured adhesive layer on one surface of said heat-resistant film substrate, wherein the cured adhesive layer is formed by photo-curing an adhesive layer formed from an adhesive composition containing 0.15-4.0 parts by weight of a photo-cationic polymerization initiator per 100 parts by weight of a graft polymer formed by graft polymerization of chains containing cyclic ether group-containing monomers onto a (meth)acrylic polymer.

Description

Adhesive tape for peeling and manufacturing method thereof

The present invention relates to an adhesive tape for re-peeling and a method of manufacturing the same. More specifically, the adhesive tape for re-peeling which is excellent in heat resistance and re-peelability without contamination to the adherend, and a method for producing the same.

In an electronic device, various substrates or wiring boards are used, and when performing component mounting, lead frame fabrication, solder processing, or heat treatment on a substrate, a masking tape is used to protect electronic components or circuits. In the case of such use, it is required that when the masking tape is attached, there is no bulging in the step, and the peeling force is less when the peeling is performed after the heating step or the like, and there is no paste residue or contamination on the adhering body. .

Various proposals have been made for such requirements. For example, it is proposed to provide an adhesive tape for heat-resistant re-peeling in which a pressure-sensitive adhesive layer obtained by crosslinking an acrylic polymer obtained by copolymerizing glycidyl (meth)acrylate and (meth)acrylic acid is provided on a heat-resistant backing film layer. (Patent Document 1) Further, an adhesive obtained by crosslinking an acrylic polymer obtained by copolymerizing a monomer having a carboxyl group by an epoxy crosslinking agent is disclosed (Patent Document 2).

Prior technical literature Patent literature

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2005-53975

[Patent Document 2] Japanese Patent Laid-Open No. Hei 5-163468

An object of the present invention is to provide an adhesive which does not cause bulging or the like in various steps after attachment, and which has a small increase in the adhesion force in the heating step, and which has no paste residue or contamination on the adherend, and heat resistance. Excellent adhesive tape for re-peeling.

In order to solve the above problems, the inventors of the present invention have been working hard to find the following adhesive tape for re-peeling, and have completed the present invention.

That is, the present invention relates to an adhesive tape for re-peeling, which comprises a heat-resistant film substrate and a cured adhesive layer provided on one surface of the heat-resistant film substrate. The hardened adhesive layer is obtained by photohardening an adhesive layer formed of an adhesive composition, and the adhesive composition is graft-polymerized on a (meth)acrylic polymer to contain a cyclic ring. 100 parts by weight of the graft polymer of the ether group-based monomer is contained in an amount of 0.15 to 4.0 parts by weight based on the photocationic polymerization initiator.

The above adhesive composition preferably further contains an isocyanate crosslinking agent.

The adhesive composition may further contain 5 to 100 parts by weight of the epoxy resin and/or oxetane resin with respect to 100 parts by weight of the graft polymer.

The gel fraction of the hardened adhesive layer is preferably from 80 to 99%.

The (meth)acrylic polymer may contain, as a monomer unit, 0.2 to 10% by weight of a monomer having a hydroxyl group based on the total amount of the (meth)acrylic polymer.

The above graft polymer can be derived from the above (meth)acrylic polymer It is obtained by graft-polymerizing 2 to 50 parts by weight of the above-mentioned cyclic ether group-containing monomer and 5 to 50 parts by weight of the other monomer in 100 parts by weight of the peroxide in the presence of 0.02 to 5 parts by weight of the peroxide.

The photocationic polymerization initiator may be a photoacid generator.

The photoacid generator is preferably dissolved without causing a precipitate when the solvent is made into ethyl acetate and adjusted to a concentration of 10%.

The storage modulus of the hardened adhesive layer at 23 ° C may be 9.0 × 10 ⁴ to 1.0 × 10 ⁶ Pa.

The heat resistant film substrate may be selected from the group consisting of polyethylene terephthalate, polyimide, aromatic polyamine, polyethylene naphthalate, and polyphenylene sulfide.

The adhesive layer may have a thickness of 0.5 to 100 μm.

The present invention relates to a method for producing an adhesive tape for re-peeling, which is used for producing an adhesive tape for re-peeling in which a cured adhesive layer is provided on one surface of a heat-resistant film substrate, and the manufacturing method includes: The adhesive composition is applied to one surface of a heat-resistant film substrate to form an adhesive layer, and the adhesive composition is graft-polymerized on a (meth)acrylic polymer to contain a ring 100 parts by weight of the graft polymer of the monomer group of the ether group, which comprises 0.15 to 4.0 parts by weight of the photocationic polymerization initiator; The step of irradiating the adhesive layer with light to harden the light.

The adhesive tape for re-peeling of the present invention can be used for an adhesive tape for shielding of an electronic circuit board or an adhesive tape for temporary fixing of an electronic component. Re-peeling of the present invention The adhesive tape is excellent in heat resistance and has an adhesiveness to such an extent that no bulging occurs in various steps, and the adhesion in the heating step does not increase, and in particular, since the acrylic adhesive is provided, the electronic circuit is not adhered. Excellent in low-molecular pollutants.

The adhesive tape for re-peeling of the present invention comprises a heat-resistant film substrate and a cured adhesive layer provided on one surface of the heat-resistant film substrate. Here, the hardened adhesive layer is obtained by photohardening an adhesive layer formed of an adhesive composition, and the adhesive composition is graft-polymerized on a (meth)acrylic polymer to contain The graft polymer obtained by chaining a monomer having a cyclic ether group contains 0.15 to 4.0 parts by weight of a photocationic polymerization initiator.

First, as the monomer unit contained in the (meth)acrylic polymer, any (meth) acrylate can be used, and it is not particularly limited. Here, for example, an alkyl (meth)acrylate having an alkyl group having 4 or more carbon atoms inclusive of 50% by weight or more of the entire (meth)acrylic polymer is preferable.

In the present specification, the term "alkyl (meth)acrylate" means a (meth) acrylate having a linear or branched alkyl group. The alkyl group has a carbon number of 4 or more, preferably a carbon number of 4 to 9. Further, (meth) acrylate means acrylate and/or methacrylate, and has the same meaning as (meth) of the present invention.

Specific examples of the alkyl (meth)acrylate include n-butyl (meth)acrylate, second butyl (meth)acrylate, tert-butyl (meth)acrylate, and (meth)acrylic acid. Isobutyl ester, n-amyl (meth)acrylate, (methyl) Isopentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, isoamyl (meth)acrylate, (meth)acrylic acid 2 -ethylhexyl ester, n-octyl (meth)acrylate, isooctyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, n-decyl (meth)acrylate , isodecyl (meth)acrylate, n-dodecyl (meth)acrylate, isotetradecyl (meth)acrylate, n-tridecyl (meth)acrylate, (methyl) N-tetradecyl acrylate, stearyl (meth) acrylate, isostearyl (meth) acrylate, and the like. Among them, n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and the like can be exemplified, and these may be used singly or in combination.

In the present invention, the alkyl (meth)acrylate is 50% by weight or more, preferably 80% by weight or more, and more preferably 90% by weight or more based on the total monomer component of the (meth)acrylic polymer. . Further, although all of the monomers may be alkyl (meth)acrylate, it is preferably 98% by weight or less, and may be 97% by weight or less.

Further, the (meth)acrylic polymer of the present invention preferably contains a hydroxyl group-containing monomer having at least one hydroxyl group in the alkyl group. That is, the single system contains one or more hydroxyalkyl groups of a hydroxyl group. Here, the hydroxyl group is preferably present at the end of the alkyl group. The carbon number of the alkyl group is preferably 4 to 12, more preferably 4 to 8, and further preferably 4 to 6. It is considered that by containing such a hydroxyl group-containing monomer, the compatibility of the position at which hydrogen abstraction is caused during graft polymerization or the homopolymer of the graft polymer and the monomer having a cyclic ether group formed during graft polymerization has The preferred effect is to prepare a graft polymer having good heat resistance.

As such a monomer, (meth)acryl oxime may be used without particular limitation. A group having a polymerizable functional group having an unsaturated double bond and having a hydroxyl group. For example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, (A) (6-hydroxyhexyl acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, hydroxyalkyl (meth)acrylate Ester; 4-hydroxymethylcyclohexyl (meth)acrylate, 4-hydroxybutyl vinyl ether, and the like. Among these, hydroxyalkyl (meth)acrylate is preferably used, and 2-hydroxyethyl (meth)acrylate and 4-hydroxybutyl (meth)acrylate are particularly preferably used.

The total amount of the hydroxyl group-containing monomer relative to the monomer component forming the (meth)acrylic polymer is preferably 0.02% by weight or more, more preferably 0.05% by weight or more, and most preferably 10% by weight or less, more preferably It is 3% by weight or less. The optimum is 0.05% by weight to 3% by weight.

In addition to the above monomers, a monomer containing an unsaturated carboxylic acid may be used as a monomer component for forming the above (meth)acrylic polymer.

As the monomer containing an unsaturated carboxylic acid, a monomer having a carboxyl group having a polymerizable functional group having an unsaturated double bond such as a (meth) acrylonitrile group or a vinyl group and having a carboxyl group can be used without particular limitation. Examples of the monomer containing an unsaturated carboxylic acid include (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, and anti-butyl Aenedioic acid, crotonic acid, and the like. These may be used alone or in combination. Among these, (meth)acrylic acid, especially acrylic acid is preferably used.

The total amount of the monomer containing an unsaturated carboxylic acid relative to the monomer component forming the (meth)acrylic polymer is preferably 0.01 to 2% by weight. More preferably, it is 0.05 to 2% by weight, further preferably 0.05 to 1.5% by weight, and particularly preferably 0.1 to 1% by weight.

As the monomer component for forming the above (meth)acrylic polymer, other comonomers may be used singly or in combination within the range not impairing the object of the present invention. Examples of the other comonomer include a (meth) acrylate having an alkyl group having a carbon number of less than 4 or a polymerizable functional group having an unsaturated double bond such as a (meth) acrylonitrile group or a vinyl group. An aromatic ring-containing monomer having an aromatic ring. Specific examples of the (meth) acrylate having an alkyl group having a carbon number of less than 4 include methyl (meth)acrylate, ethyl (meth)acrylate, and propyl (meth)acrylate; Specific examples of the monomer of the aromatic ring include phenoxyethyl (meth)acrylate, benzyl (meth)acrylate, phenol ethylene oxide modified (meth)acrylate, and (methyl). 2-naphthylethyl acrylate, 2-(4-methoxy-1-naphthalenyloxy)ethyl (meth)acrylate, phenoxypropyl (meth)acrylate, phenoxydiethylene glycol (A) Acrylate, poly(meth)acrylic acid styrene ester, and the like.

Further, examples of the other comonomer include an acid anhydride group-containing monomer such as maleic anhydride or itaconic anhydride; a caprolactone adduct of acrylic acid; styrenesulfonic acid or allylsulfonic acid; (Methyl) acrylamide-2-methylpropanesulfonic acid, (meth)acrylamide, propanesulfonic acid, sulfopropyl (meth)acrylate, (meth)acryloxynaphthalenesulfonic acid, etc. a monomer having an acid group; a monomer having a phosphate group such as 2-hydroxyethyl acryloyl phosphate; a methoxyethyl (meth)acrylate; an ethoxyethyl (meth)acrylate; An alkoxyalkyl acrylate monomer or the like.

Further, as the other comonomer, a vinyl monomer such as vinyl acetate, vinyl propionate, styrene, α-methylstyrene or N-vinyl caprolactam may be used; (meth)acrylic acid may be used. An epoxy group-containing monomer such as glycidyl ester, (meth)acrylic acid methyl glycidyl ester, (meth)acrylic acid 3,4-epoxycyclohexylmethyl ester; (meth)acrylic acid polyethylene glycol ester; Alcohol acrylate monomer such as polypropylene glycol (meth)acrylate, methoxyethylene glycol (meth)acrylate or methoxypolypropylene glycol (meth)acrylate; tetrahydrofurfuryl (meth)acrylate An acrylate monomer such as fluorine (meth) acrylate, poly methoxy (meth) acrylate or 2-methoxy ethyl acrylate; a monomer containing a guanamine group, a monomer containing an amine group, and containing Monomethylene amide monomer, N-propylene fluorenyl Porphyrin, vinyl ether monomer, and the like.

The (meth)acrylic polymer of the present invention preferably has a weight average molecular weight of 600,000 or more, more preferably 700,000 or more and 2,000,000 or less. In addition, the weight average molecular weight is a value measured by GPC (Gel Permeation Chromatography) and calculated by polystyrene conversion.

The production of such a (meth)acrylic polymer can be carried out by appropriately selecting a known production method such as solution polymerization, bulk polymerization, emulsion polymerization, or various radical polymerization. Further, the obtained (meth)acrylic polymer may be a random copolymer or a block copolymer.

Further, in the solution polymerization, for example, ethyl acetate, toluene or the like can be used as the polymerization solvent. As a specific example of the solution polymerization, the reaction may be carried out under a flow of an inert gas such as nitrogen, and a polymerization initiator may be added, usually at a reaction temperature of about 50 to 70 ° C for about 5 to 30 hours.

Polymerization initiator, chain transfer agent, emulsifier, etc. used in radical polymerization It is not particularly limited and can be appropriately selected and used. Further, the weight average molecular weight of the (meth)acrylic polymer can be controlled depending on the amount of the polymerization initiator, the chain transfer agent used, and the reaction conditions, and the appropriate amount can be adjusted according to the types of the polymers.

Examples of the polymerization initiator include 2,2'-azobisisobutyronitrile, 2,2'-azobis(2-amidinopropane) dihydrochloride, and 2,2'-azobis. [2-(5-Methyl-2-imidazolin-2-yl)propane] dihydrochloride, 2,2'-azobis(2-methylpropionamidine) disulfate, 2,2'- Azobis(N,N'-dimethyleneisobutylphosphonium), 2,2'-azobis[N-(2-carboxyethyl)-2-methylpropionamidine] hydrate (and pure light) An azo initiator such as VA-057) manufactured by Pharmaceutical Company, persulfate such as potassium persulfate or ammonium persulfate, di(2-ethylhexyl) peroxydicarbonate or di(dioxycarbonate) Tertiary butylcyclohexyl) ester, di-second butyl peroxydicarbonate, tert-butyl peroxy neodecanoate, third hexyl peroxypivalate, tert-butyl peroxypivalate, Dilaurin peroxide, di-n-octyl peroxide, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate, bis(4-methylbenzhydryl) peroxide, Peroxides such as benzamidine oxide, tert-butyl peroxyisobutyrate, 1,1-di(trihexylperoxy)cyclohexane, tert-butyl hydroperoxide, hydrogen peroxide, etc. Starting agent, group of persulfate and sodium bisulfite , A combination of a peroxide with sodium ascorbate or the like of a peroxide with a reducing agent a combination of the redox initiator and so forth, but are not limited to such.

The polymerization initiator may be used singly or in combination of two or more kinds, and the total content is preferably from 0.005 to 1 part by weight, more preferably from 0.02 to 0.5 part by weight, per 100 parts by weight of the total amount of the monomer component.

Further, for example, 2,2'-azobisisobutyronitrile is used as a polymerization initiator. When the (meth)acrylic polymer having a weight average molecular weight is produced, the amount of the polymerization initiator to be used is preferably from about 0.06 to 0.3 parts by weight, based on 100 parts by weight of the total of the monomer components. It is set to about 0.08 to 0.2 parts by weight.

Examples of the chain transfer agent include lauryl mercaptan, glycidyl mercaptan, mercaptoacetic acid, 2-mercaptoethanol, thioglycolic acid, 2-ethylhexyl thioglycolate, and 2,3-didecyl. -1-propanol and the like. The chain transfer agent may be used singly or in combination of two or more kinds, and the total content is about 0.1 part by weight or less based on 100 parts by weight of the total of the monomer components.

Further, examples of the emulsifier used in the case of emulsion polymerization include sodium lauryl sulfate, ammonium lauryl sulfate, sodium dodecylbenzenesulfonate, polyoxyethylene alkyl ether sulfate, and polyoxyethylene oxide. Anionic emulsifier such as sodium phenyl ether sulfate, nonionic emulsifier such as polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene fatty acid ester, polyoxyethylene-polyoxypropylene block polymer Wait. These emulsifiers may be used alone or in combination of two or more.

Further, as the reactive emulsifier, as an emulsifier to which a radical polymerizable functional group such as a propenyl group or an allyl ether group is introduced, specifically, for example, AQUALON HS-10, AQUALON HS-20, AQUALON KH-10 AQUALON BC-05, AQUALON BC-10, AQUALON BC-20 (all of which are manufactured by First Industrial Pharmaceutical Co., Ltd.), ADEKA REASOAP SE10N (manufactured by Adeka Co., Ltd.), and the like. Since the reactive emulsifier is incorporated into the polymer chain after polymerization, the water resistance is improved and is preferred. The amount of the emulsifier used is 0.3 to 5 parts by weight based on 100 parts by weight of the total of the monomer components, and more preferably 0.5 to 1 weight in terms of polymerization stability or mechanical stability. Quantities.

The glass transition temperature (Tg) of the (meth)acrylic polymer is 250 K or less, preferably 240 K or less. Further, the glass transition temperature is preferably 200 K or more. When the glass transition temperature is 250 K or less, a pressure-sensitive adhesive composition having good heat resistance and excellent internal cohesive force is formed. Such a (meth)acrylic polymer can be adjusted by appropriately changing the monomer component or composition ratio used. Further, such a glass transition temperature can be, for example, 0.06 to 0.2 parts by using a polymerization initiator such as azobisisobutyronitrile or benzoyl peroxide, and a polymerization solvent such as ethyl acetate under a nitrogen stream. It is obtained by reacting at 50 ° C ~ 70 ° C for 8 ~ 30 hours. Here, the glass transition temperature (Tg) can be calculated from the following Fox equation.

1/Tg=W1/Tg1+W2/Tg2+W3/Tg3+...

The above Tg1, Tg2, Tg3, etc., the glass transition temperature of each of the homopolymers 1, 2, and 3 of the copolymerization component is represented by an absolute temperature, and W1, W2, W3, etc. are the weight fraction of each copolymerization component. Further, the glass transition temperature (Tg) of the homopolymer was obtained according to Polymer Handbook (4th edition, John Wiley & Sons. Inc.).

Then, the (meth)acrylic polymer thus obtained is directly supplied to the graft polymerization, or a solution obtained by diluting a diluent is supplied to the graft polymerization.

The diluent is not particularly limited, and examples thereof include ethyl acetate and toluene.

The graft polymerization is carried out by reacting a (meth)acrylic polymer, a monomer having a cyclic ether group, a monomer having any cyclic ether group, and another monomer.

Here, the monomer having a cyclic ether group is not particularly limited, and is preferably contained. a monomer of an epoxy group, a monomer containing an oxetane group, or a combination of both.

Examples of the epoxy group-containing monomer include glycidyl acrylate, glycidyl methacrylate, 3,4-epoxycyclohexylmethyl acrylate, 3,4-epoxycyclohexylmethyl methacrylate or acrylic acid. 4-hydroxybutyl ester glycidyl ether or the like, which may be used singly or in combination.

Examples of the oxetane group-containing monomer include 3-oxetanylmethyl (meth)acrylate and 3-methyl-3-oxetanyl (meth)acrylate. , 3-ethyl-3-oxetanylmethyl (meth)acrylate, 3-butyl-3-oxetanyl (meth)acrylate or (meth)acrylic acid 3- Hexyl-3-oxetanylmethyl ester, these may be used singly or in combination.

The amount of the monomer having a cyclic ether group is preferably 2 parts by weight or more, and more preferably 3 parts by weight or more based on 100 parts by weight of the (meth)acrylic polymer. The upper limit is not particularly limited, but is preferably 100 parts by weight or less, more preferably 50 parts by weight or less, still more preferably 30 parts by weight or less. When the amount of the monomer having a cyclic ether group is 2 parts by weight or more, the composition functions as an adhesive binder. On the other hand, when it is 100 parts by weight or more, the viscosity may be reduced and the initial adhesion may occur. difficult.

In the graft polymerization, other monomers which are co-grafted may also be used together with the monomer having a cyclic ether group. The monomer which is not a cyclic ether group is not particularly limited, and examples thereof include an alkyl ester having 1 to 9 carbon atoms of (meth)acrylic acid. Specific examples of the alkyl (meth)acrylate include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, and 2-ethylhexyl acrylate. Further, it is also possible to use: (meth)acrylic acid cyclohexyl ester, (meth)acrylic acid An alicyclic (meth) acrylate such as an ester. These may be used alone or in combination.

If other monomers which are co-grafted are used in the grafting, the adhesive can be easily cured, for example, in the case of photohardening, the amount of light can be reduced, and in the case of heat hardening, heat can be reduced. The amount of hardening catalyst. It is presumed that the reason is that the mobility of the graft chain is improved, or the compatibility between the graft chain or the by-produced ungrafted chain and the dry polymer is improved.

The other monomer is also preferably selected from the same monomers as those of the main chain (dry), that is, the (meth)acrylic polymer.

In the case of formulating a monomer other than a monomer having a cyclic ether group, the weight ratio of the other monomer to the monomer having a cyclic ether group is calculated by using a monomer having a cyclic ether group: other monomers. The best is 90:10 to 10:90, more preferably 80:20 to 20:80. If the content of the other monomer is small, the effect of lowering the amount of photocuring for hardening may be insufficient, and if it is large, the peeling resistance after photocuring may increase.

The graft polymerization conditions are not particularly limited and can be carried out by a method known to a person skilled in the art. In the polymerization, it is preferred to use a peroxide as a polymerization initiator.

The amount of such a polymerization initiator is 0.02 to 5 parts by weight based on 100 parts by weight of the (meth)acryl-based polymer. When the amount of the polymerization initiator is small, the graft polymerization reaction requires an excessive amount of time. When the amount of the polymerization initiator is large, a large amount of the monomer having a cyclic ether group is formed. The polymer is therefore not good.

Regarding graft polymerization, for example, if it is solution polymerization, a monomer containing a cyclic ether group may be added to a solution of a (meth)acrylic polymer and may be adjusted. The solvent of the entire viscosity is 0.02 to 5 parts by weight of a peroxide-based polymerization initiator such as benzoic acid peroxide after being replaced by nitrogen, and heated at 50 to 80 ° C for 4 to 15 hours. However, it is not limited to this.

The state of the obtained graft polymer (molecular weight, the size of the branch of the graft polymer, and the like) can be appropriately selected depending on the reaction conditions.

The adhesive composition for forming the adhesive tape for re-peeling of the present invention contains the graft polymer thus obtained and a photocationic polymerization initiator.

As the photocationic polymerization initiator, any photocationic polymerization initiator known to a person skilled in the art can be preferably used. More specifically, at least one selected from the group consisting of arylsulfonium hexafluorophosphate, triarylsulfonium salt, hexafluorophosphonium phosphate, and bis(alkylphenyl)phosphonium hexafluorophosphate can be used.

The photocationic polymerization initiator may be used singly or in combination of two or more kinds, and the total content is 0.15 to 4.0 parts by weight, preferably 0.2 to 3.9 parts by weight, based on 100 parts by weight of the graft polymer.

The photocationic initiator is turbid when it is prepared into a 10% ethyl acetate solution and cannot be completely dissolved. When it is mixed in a polymer, if it exceeds a certain amount, it does not dissolve, and may hinder the effect or cause contamination. Therefore, in order to better harden, it is preferred to have good solubility in a polymer solution. More preferred is a photocationic initiator which will dissolve in a 10% solution of ethyl acetate. Examples of such a photocationic initiator include a CPI series of San-Apro Co., Ltd., or a TAS series of Sumitomo Seika Co., Ltd., and the like. In addition, ESACURE 1064 manufactured by LAMBERTI can also be used.

In the adhesive composition for forming the adhesive tape for re-peeling of the present invention, a crosslinking agent may be added as needed. The crosslinking agent is not particularly limited and can be used. An isocyanate-based crosslinking agent which is a compound having two or more isocyanate groups (including an isocyanate-regenerating functional group temporarily protected by a block agent or a quantitative amount of an isocyanate group) in one molecule is exemplified.

Examples of the isocyanate crosslinking agent include aromatic isocyanates such as toluene diisocyanate and xylene diisocyanate; alicyclic isocyanates such as isophorone diisocyanate; and aliphatic isocyanates such as hexamethylene diisocyanate.

More specifically, examples thereof include low-carbon aliphatic polyisocyanates such as butyl diisocyanate and hexamethylene diisocyanate; cyclopentyl diisocyanate, cyclohexyl diisocyanate, isophorone diisocyanate, and the like. Alicyclic diisocyanates such as alicyclic isocyanates, 2,4-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylene diisocyanate, polymethylene polyphenyl isocyanate, trimethylolpropane / Toluene diisocyanate trimer adduct (manufactured by NIPPON POLYURETHANE INDUSTRY, trade name Coronate L), trimethylolpropane/hexamethylene diisocyanate trimer adduct (manufactured by NIPPON POLYURETHANE INDUSTRY, trade name Coronate) HL), isocyanate ester of hexamethylene diisocyanate (manufactured by NIPPON POLYURETHANE INDUSTRY, trade name Coronate HX), polyether polyisocyanate, polyester polyisocyanate, and various An adduct of an alcohol, a polyisocyanate which is polyfunctionalized by an isocyanurate bond, a biuret bond, an allophanate bond or the like. Among these, in terms of a faster reaction rate, it is preferred to use an aliphatic isocyanate.

The above isocyanate crosslinking agent may be used singly or in combination of two. More preferably, the total content is 0.05 to 5 parts by weight, more preferably 0.1 to 4 parts by weight, even more preferably 0.2 to 50 parts by weight of the above-mentioned isocyanate compound crosslinking agent. 3 parts by weight. It can be suitably contained in consideration of the cohesive force, the prevention of peeling in the durability test, and the like.

Such an isocyanate crosslinking agent is preferably used because it crosslinks the main chain of the binder polymer and also contributes to the hardening reaction of the cyclic ether group located on the graft chain.

Further, an organic crosslinking agent or a polyfunctional metal chelate compound may be used in combination as a crosslinking agent. The organic crosslinking agent is an epoxy crosslinking agent (a compound having two or more epoxy groups in one molecule). Examples of the epoxy-based crosslinking agent include ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, diglycidyl phthalate acrylate, and spirodiol diglycidyl ether. These may be used alone or in combination of two or more.

Polyfunctional metal chelates are those in which a polyvalent metal is covalently bonded or coordinated to an organic compound. Examples of the polyvalent metal atom include Al, Cr, Zr, Co, Cu, Fe, Ni, V, Zn, In, Ca, Mg, Mn, Y, Ce, Sr, Ba, Mo, La, Sn, and Ti. Wait. Examples of the atom in the organic compound which is a covalent bond or a coordinate bond include an oxygen atom and the like. Examples of the organic compound include an alkyl ester, an alcohol compound, a carboxylic acid compound, an ether compound, and a ketone compound.

In the present invention, it may be further added An oxazoline crosslinking agent or a peroxide is used as a crosslinking agent.

As The oxazoline crosslinking agent can be used in the molecule without any particular limitation. An oxazoline group. The oxazoline group can be 2- Oxazolinyl, 3- Oxazolinyl, 4- Any of the oxazoline groups. As An oxazoline crosslinking agent, preferably an addition polymerization property a polymer obtained by copolymerizing an oxazoline with an unsaturated monomer, particularly preferably 2-isopropenyl-2- Oxazoline as addition polymerization Oxazoline. For example, the product name "Epocros WS-500" manufactured by Nippon Shokubai Co., Ltd., and the like can be cited.

As the peroxide, if a radical active species is generated by heating and the base polymer of the adhesive composition is crosslinked, it can be suitably used, but it is preferably used in consideration of workability or stability. The one-minute half-life temperature is 80 ° C ~ 160 ° C peroxide, more preferably the use of 1 minute half-life temperature of 90 ° C ~ 140 ° C peroxide.

Examples of the peroxide which can be used include di(2-ethylhexyl)peroxydicarbonate (1 minute half-life temperature: 90.6 ° C), and di(4-tert-butylcyclohexyl)peroxydicarbonate. Ester (1 minute half-life temperature: 92.1 ° C), di-second butyl peroxydicarbonate (1 minute half-life temperature: 92.4 ° C), perbutyl neodecanoate (1 minute half-life temperature: 103.5 ° C), Third hexyl peroxypivalate (1 minute half-life temperature: 109.1 ° C), third butyl peroxypivalate (1 minute half-life temperature: 110.3 ° C), dilaurin peroxide (1 minute half-life temperature: 116.4) °C), di-n-octyl peroxide (1 minute half-life temperature: 117.4 ° C), 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate (1 minute half-life temperature: 124.3 ° C) , bis(4-methylbenzhydrazide) peroxide (1 minute half-life temperature: 128.2 ° C), benzamidine peroxide (1 minute half-life temperature: 130.0 ° C), third butyl peroxybutyrate (1 Minute half-life temperature: 136.1 ° C), 1,1-di(trihexylperoxy)cyclohexane (1 minute half-life temperature: 149.2 ° C), and the like. Especially in the cross-linking reaction In terms of efficiency, bis(4-tert-butylcyclohexyl)peroxydicarbonate (1 minute half-life temperature: 92.1 ° C) and dilaurin peroxide (1 minute half-life temperature: 116.4 ° C) can be preferably used. , benzoquinone peroxide (1 minute half-life temperature: 130.0 ° C) and the like.

Further, the half-life of the peroxide is an index indicating the decomposition rate of the peroxide, and means a time period until the residual amount of the peroxide is half. The decomposition temperature for obtaining the half-life at any time, or the half-life time at any temperature, is described in the manufacturer's catalog, etc., for example, in the Organic Peroxide Catalogue, 9th Edition (2003) May) and so on.

The peroxide may be used singly or in combination of two or more kinds, and the total content is 0.01 to 2 parts by weight, preferably 0.04 to 1.5 parts by weight based on 100 parts by weight of the graft polymer. The parts by weight are more preferably 0.05 to 1 part by weight. In order to adjust workability, secondary workability, crosslinking stability, peelability, and the like, it can be appropriately selected within this range.

Further, the method for measuring the amount of decomposition of the peroxide remaining after the reaction treatment can be measured, for example, by HPLC (high performance liquid chromatograph).

More specifically, for example, about 0.2 g of the adhesive composition after the reaction treatment can be taken out, immersed in 10 ml of ethyl acetate, and subjected to vibration extraction at 25 ° C for 3 hours at 120 rpm, and then in a chamber. Allow to stand for 3 days. Then, 10 ml of acetonitrile was added, and the mixture was shaken at 120 rpm for 30 minutes at 25 ° C, and about 10 μl of the extract obtained by filtration through a membrane filter (0.45 μm) was injected into HPLC and analyzed, and reacted as a reaction. Post-treatment oxygenation The amount of the compound.

The adhesive layer is formed by the above-mentioned crosslinking agent. However, when the adhesive layer is formed, it is necessary to adjust the total amount of the crosslinking agent to be added, and the influence of the crosslinking treatment temperature or the crosslinking treatment time is sufficiently considered.

The adhesive composition for forming the adhesive tape for re-peeling of the present invention may contain an epoxy resin or an oxetane resin in order to further improve the adhesion or heat resistance.

Examples of the epoxy resin include bisphenol A type, bisphenol F type, bisphenol S type, brominated bisphenol A type, hydrogenated bisphenol A type, bisphenol AF type, biphenyl type, naphthalene type, and anthracene. Type, phenol novolac type, cresol novolac type, trihydroxyphenylmethane type, tetraphenol ethane type and other difunctional epoxy resin or polyfunctional epoxy resin, and carbendazim type, isocyanuric acid An epoxy resin such as a glycidylamine type such as a glycidyl ester type. These epoxy resins may be used alone or in combination of two or more.

The epoxy resin is not limited, and a commercially available epoxy resin can be used. Such a commercially available epoxy resin is not limited, and includes, for example, the following known epoxy resins: jER828, jER806, etc. of Japan Epoxy Resins Co., Ltd. as a bisphenol type epoxy resin; Japan as an alicyclic epoxy resin YX8000, YX8034, etc. of Epoxy Resins Co., Ltd.; EP4000, EP4005, etc. of ADEKA Co., Ltd.; DENACOL EX-313, EX-512, EX-614B of Changchun Chemical Co., Ltd., which is a polyglycidyl ether of polyhydric alcohol , EX-810, etc.

As the oxetane resin, xylene dioxetane such as 1,4-bis{[(3-ethyl-3-oxetanyl)methoxy]methyl}benzene can be used. , 3-B 3-(3-ethyloxetan-3-yl)methoxy}methyl}oxetane, 3-ethylhexyloxetane, 3-ethyl-3 A known oxetane resin such as hydroxyoxetane or 3-ethyl-3-hydroxymethyloxetane. These oxetane resins may be used alone or in combination of two or more.

The oxetane resin is not limited, and a commercially available resin can be used. Such a commercially available oxetane resin is exemplified by ARONE OXETANE OXT-121, OXT221, OXT101, and OXT212 of East Asia Synthetic Co., Ltd., but is not limited thereto.

Any one or a combination of such an epoxy resin and an oxetane resin can be used in the adhesive composition for forming the adhesive tape for re-peeling of the present invention.

In the present invention, in the case of containing an epoxy resin and/or an oxetane resin, the total amount thereof is preferably 5 parts by weight or more, more preferably 10 parts by weight based on 100 parts by weight of the above graft polymer. The amount is preferably 100 parts by weight or less, more preferably 70 parts by weight or less. When the total amount is 5 parts by weight or more, a remarkable effect can be confirmed in terms of improvement in adhesion force and improvement in heat resistance. When the total amount exceeds 100 parts by weight, the curing may not be sufficiently performed.

In the present invention, when an epoxy resin is added to a graft polymer obtained by grafting a monomer containing a cyclic ether group onto an acrylic polymer, it is possible to prepare a paste which does not bleed out before hardening, and A composition of a good adhesive layer is made. The reason is considered to be that the grafted cyclic ether group is compatible with the low molecular weight epoxy resin to form a strong adhesive layer structure.

Further, in the adhesive composition for forming the adhesive tape for re-peeling of the present invention, an adhesion-imparting agent or a softening agent may be formulated. Adhesion-imparting agent relative to grafting The polymer may be used in an amount of 10 to 100 parts by weight, preferably 20 to 80 parts by weight, based on 100 parts by weight of the polymer.

Further, in the adhesive composition for forming the adhesive tape for re-peeling of the present invention, in order to improve the water resistance at the interface, 0.01 to 2 parts by weight of the decane coupling agent may be blended with respect to 100 parts by weight of the graft polymer. It is preferably formulated in an amount of 0.02 to 1 part by weight. If the amount is too large, the adhesion to the liquid crystal cell increases and the removability is deteriorated. If the amount is too small, the water resistance is not improved, which is not preferable.

Examples of the decane coupling agent include 3-glycidoxypropyltrimethoxydecane, 3-glycidoxypropylmethyldiethoxydecane, and 2-(3,4 epoxycyclohexyl)ethyl. An epoxy group-containing decane coupling agent such as trimethoxy decane, 3-aminopropyltrimethoxydecane, N-2 (aminoethyl) 3-aminopropylmethyldimethoxydecane, 3- Amino-containing decane coupling agent such as triethoxysulfonyl-N-(1,3-dimethyl-butylene)propylamine, 3-propenyloxypropyltrimethoxydecane, 3-methyl A decane coupling agent containing a (meth) acrylonitrile group, a decane coupling agent containing an isocyanate group such as 3-isocyanate propyl triethoxy decane, or the like, such as acryloxypropyltriethoxy decane.

Further, anti-aging or antioxidants may be added. As such an anti-aging or antioxidant, for example, BASF's hindered phenol-based antioxidant Irganox series, or SORT Chemical Co., Ltd. K-NOX series, ADEKA Co., Ltd. Adekastab and the like can be used, and these can be used alone. Add or mix to add multiple species.

The adhesive composition for forming the adhesive tape for re-peeling of the present invention may further contain other known additives, and may be appropriately added according to the use, for example, a powder such as a coloring agent or a pigment, a dye, a surfactant, and a plasticizer. , Adhesive imparting agent, surface lubricant, leveling agent, softener, antioxidant, anti-aging agent, light stabilizer, ultraviolet absorber, polymerization inhibitor, inorganic or organic filler, metal powder, particulate matter, foil And so on. Further, a redox system to which a reducing agent is added may be used within a controllable range.

The adhesive layer contained in the adhesive tape for re-peeling of the present invention can be formed by applying the above-mentioned adhesive composition to one surface of a heat-resistant film substrate, drying and removing a polymerization solvent or the like, and performing crosslinking treatment. Thereafter, it is formed by photohardening. Alternatively, the adhesive layer for re-peeling which is excellent in heat resistance can be formed by transferring the adhesive layer formed on the separator (release film) to the heat-resistant film substrate.

In the heat-resistant film substrate of the present invention, if the temperature in the heating step is about 160 ° C, the polyethylene terephthalate film is sufficient, and if it is at least the above, the polyimide may be preferably used. A film of aromatic polyamine, polyethylene naphthalate, polyphenylene sulfide or the like. Such a film is preferably used in a thickness of 5 to 100 μm. The adhesive tape for re-peeling of the present invention includes various forms such as a sheet shape or an elongated strip shape.

More specifically, the method of forming the adhesive layer can be achieved, for example, by applying the above-mentioned adhesive composition to a release-treated separator or the like, drying and removing a polymerization solvent or the like, and crosslinking. After the treatment, an adhesive layer is formed and transferred to a heat-resistant film substrate, or the adhesive composition is initially applied onto a heat-resistant film substrate, and a polymerization solvent or the like is dried to form an adhesive layer. The method.

When the adhesive is applied, one of the polymerization solvents may be newly added as appropriate. More than one solvent.

As the release-treated separator, a polyoxynitride release liner can be preferably used. Examples of the constituent material of the release liner include polyethylene, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film, and ethylene-vinyl acetate copolymerization. Plastic film such as film, polybutylene terephthalate film, polyurethane film, polypropylene, polyethylene terephthalate, polyester film, porous materials such as paper, cloth, and non-woven fabric, A plastic film can be preferably used from the viewpoint of excellent surface smoothness, such as a mesh, a foamed sheet, a metal foil, and a suitable sheet such as the laminate. Alternatively, a sheet, a mesh, a foam, a metal foil, and a suitable sheet such as the laminate may be mentioned.

The method of applying the adhesive composition for forming the adhesive tape for re-peeling of the present invention onto the liner or the heat-resistant film substrate and drying to form an adhesive layer, as a method of drying the adhesive The appropriate method can be appropriately adopted depending on the purpose. It is preferred to use a method of drying the above coated film by heating. The heating and drying temperature is preferably from 40 ° C to 200 ° C, more preferably from 50 ° C to 180 ° C, and particularly preferably from 70 ° C to 170 ° C. By setting the heating temperature to the above range, an adhesive having excellent adhesive properties can be obtained.

The drying time can be appropriately adjusted to the appropriate time. The drying time is preferably from 5 seconds to 20 minutes, more preferably from 5 seconds to 10 minutes, and particularly preferably from 10 seconds to 5 minutes.

Further, a pressure-sensitive adhesive layer may be formed on the surface of the heat-resistant film substrate, or various adhesion treatments such as corona treatment and plasma treatment may be performed to form an adhesive layer. Further, the surface of the adhesive layer can be easily treated.

As a method of forming the adhesive layer, various methods can be used. Specific examples thereof include roll coating, contact roll coating, gravure coating, reverse coating, roll coating, spray coating, dip roller coating, bar coating, blade coating, and gas coating. Knife coating, curtain coating, lip coating, and extrusion coating methods such as a slit extrusion coater.

The thickness of the adhesive layer is not particularly limited, and is, for example, about 0.5 to 100 μm. It is preferably 2 to 50 μm, more preferably 3 to 25 μm, and still more preferably 3 to 15 μm.

In the case where the above adhesive layer is exposed, the adhesive layer may be protected by a release-treated sheet (separator) until it is used for practical use.

Examples of the constituent material of the protective separator include a plastic film such as polyethylene, polypropylene, polyethylene terephthalate or polyester film, and a porous material such as paper, cloth or non-woven fabric. A plastic film can be preferably used from the viewpoint of excellent surface smoothness, such as a foamed sheet, a metal foil, and a suitable sheet such as the laminate.

The plastic film is not particularly limited as long as it can protect the adhesive layer, and examples thereof include a polyethylene film, a polypropylene film, a polybutene film, a polybutadiene film, and polymethylpentene. Film, polyvinyl chloride film, vinyl chloride copolymer film, polyethylene terephthalate film, polybutylene terephthalate film, polyurethane film, ethylene-vinyl acetate film, etc. .

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

The adhesive composition constituting the adhesive tape for re-peeling of the present invention can be hardened by irradiating a specific light. The adhesive tape for re-peeling of the present invention has a photo-curable adhesive layer which is reliable for the adhesion of the adherend or the adhesion of the adherend to the member.

The light for irradiation is not particularly limited, and is preferably an active energy ray such as ultraviolet rays, visible light, or electron beams. The cross-linking treatment by ultraviolet irradiation can be carried out using a suitable ultraviolet source such as a high pressure mercury lamp, a low pressure mercury lamp, an excimer laser, or a metal halide lamp. In this case, the amount of ultraviolet rays to be irradiated can be appropriately selected depending on the degree of crosslinking required, and is usually selected in the range of 0.2 to 10 J/cm ² in the case of ultraviolet rays. The temperature at the time of irradiation is not particularly limited, but considering the heat resistance of the support, it is preferably about 140 °C.

Furthermore, the amount of light is UVA (320-390 nm), UVB (280-320 nm), UVC (250-260 nm), UVV (395-445 nm) of UV Power Puck manufactured by Electronic Instrumentation and Technology Inc. Expressed in terms of cumulative amount.

By irradiating the active energy ray, the photocationic initiator is decomposed to generate an acid, and a hardening reaction by a cyclic ether group is carried out.

The gel adhesive layer of the present invention preferably has a gel fraction of 80 to 98%, preferably an adhesive layer having a very high cohesive force. The storage modulus at 23 ° C is preferably 9.0 × 10 ⁴ to 1.0 × 10 ⁶ Pa, and is still adhesive, so that it is an adhesive composition and an adhesive sheet excellent in heat resistance.

Here, the term "photohardening reaction" means a state achieved by irradiation with light of 0.2 J/cm ² or more.

The adhesive tape for re-peeling of the present invention is obtained in the above manner and can be used in various applications for shielding or fixing.

Example

Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited to the examples. Furthermore, the parts and % in each case are based on weight. Hereinafter, room temperature conditions which are not specifically defined are 23 ° C, 65% RH (1 hour or 1 week).

<Measurement of Weight Average Molecular Weight>

The weight average molecular weight of the obtained (meth)acrylic polymer was measured by GPC (gel permeation chromatography). The sample was dissolved in dimethylformamide to form a 0.1% by weight solution, which was allowed to stand overnight, and then filtered through a 0.45 μm membrane filter.

. Analytical device: HLC-8120GPC manufactured by Tosoh

. Pipe column: G7000H _XL +GMH _XL +GMH _XL manufactured by Tosoh

. Column size: 7.8 mm Φ × 30 cm each, total 90 cm

. Lysate: tetrahydrofuran (concentration 0.1% by weight)

. Flow rate: 0.8 ml/min

. Detector: Differential Refractometer (RI)

. Column temperature: 40 ° C

. Injection volume: 100 μl

. Standard sample: polystyrene

<Measurement of gel fraction>

The dried and cross-linked adhesive (initial weight W1) was immersed in an ethyl acetate solution, and after standing at room temperature for 1 week, the insoluble matter was taken out, and the dried weight (W2) was measured, and the following Ways to get it.

Gel fraction = (W2/W1) × 100

<Method of measuring the force>

The adhesive tape for re-peeling obtained in the examples and the comparative examples was cut into a width of 20 mm and a length of 100 mm to prepare a sample, which was attached to an alkali-free glass plate by reciprocating once with a 2 Kg roller at 23 ° C * After standing for 30 minutes under the conditions of 50% RH, the peeling adhesion force (N/20 mm) was measured at a peeling angle of 90° and a peeling speed of 300 mm/min, and the obtained value was used as an initial adhesion force.

The attached sample was heated in an oven at 260 ° C for 5 minutes, and allowed to stand under conditions of 23 ° C * 50% RH for 30 minutes, and the peeling force was measured at a peeling angle of 90 ° and a peeling speed of 300 mm / minute (N/20). Mm), the obtained value is taken as the heating force. In the state of contamination of the adherend, if there is residual or contamination of the paste on the peeling surface, it is set to ×, and if it is not observed at all, it is set to ○.

<Method for measuring dynamic viscoelasticity>

Device: ARES manufactured by TA Instruments

Deformation mode: twist

Measuring frequency: fixed frequency 1 Hz

Heating rate: 5 ° C / min

Measuring temperature: measured from the glass transition temperature of the adhesive to 160 ° C

Shape: parallel plate 8.0 mmΦ

Sample thickness: 0.5~2 mm (installation initial)

Read the storage modulus (G') at 23 ° C

(Example 1)

100 parts by weight of n-butyl acrylate and 3 parts by weight of 4-hydroxybutyl acrylate in a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen gas introduction tube, and a cooler, and 2,2'-even as a polymerization initiator. 0.1 parts by weight of nitrogen diisobutyronitrile was charged together with 200 parts by weight of ethyl acetate, and nitrogen gas was introduced while slowly stirring for 1 hour, and then the liquid temperature in the flask was maintained at about 60 ° C for 10 hours. An acrylic polymer solution having a weight average molecular weight of 20,000,000 was prepared. The glass transition temperature of the obtained acrylic polymer was 231 K.

The obtained acrylic polymer solution was diluted with ethyl acetate in such a manner that the solid content became 25% to prepare a diluted solution (I). In a 4-necked flask equipped with a stirring blade, a thermometer, a nitrogen inlet tube, and a cooler, 20 parts of 4-hydroxybutyl acrylate glycidyl ether was added to 400 parts by weight of the diluted solution (I), and acrylic acid was added. 20 parts of ester and 0.2 part of benzamidine peroxide were introduced, and nitrogen gas was introduced while slowly stirring for 1 hour, and then the liquid temperature in the flask was maintained at about 65 ° C for 4 hours, followed by polymerization at 70 ° C for 4 hours. A graft polymer solution was obtained.

Then, one part of a triarylsulfonium salt ("CPI-200K" by San-Apro Co., Ltd.) and an isocyanate type crosslinking agent (NCO) were prepared with respect to 100 parts by weight of the solid content of the graft polymer solution obtained in the above manner. Crosslinking agent, "Takenate D110N" manufactured by Mitsui Chemicals Co., Ltd. 0.4 parts, anti-aging agent An adhesive solution was prepared by dissolving 1.0 part of a hindered phenol-based anti-aging agent ("Irganox 1010" manufactured by Ciba Japan Co., Ltd.).

The adhesive solution was applied to a 25 μm polyimine film by drying the adhesive layer to a thickness of 6 μm, and dried at 120 ° C for 3 minutes to adhere to the adhesive surface. 38 μm polyethylene terephthalate film (MRF38 manufactured by Mitsubishi Plastics Co., Ltd.) by oxygen stripping treatment.

Then, using a metal halide UV (ultraviolet) lamp, the adhesive layer is irradiated with 1.2 J/cm ² from the PET (Polyethylene terephthalate) film side, and at 50 ° C. The adhesive tape for re-peeling of the present invention was prepared by aging for 2 days.

The adhesive tape for re-peeling of Examples 2 to 10, 12 and Comparative Examples 1 to 4 was produced in the same manner as in Example 1 except that the amounts of the isocyanate-based crosslinking agent and the photocationic polymerization initiator were changed, and the amount of light was changed. . In the eleventh embodiment, about 5 parts by weight of 4-hydroxybutyl acrylate was used to prepare an acrylic polymer solution having a weight average molecular weight of 930,000 (glass transition temperature: 235 K). Further, in Example 11, 4-hydroxybutyl acrylate glycidyl ether was mixed with acrylic acid in order to prepare a graft portion. The esters were each set to 50 parts.

Here, as the photocationic polymerization initiators, in Examples 1 to 11 and Comparative Examples 1 to 4, a triarylsulfonium salt ("CPI-200K" manufactured by San-Apro Co., Ltd.) was used in the same manner as in the examples, and in Example 12 LAMBERTI's ESACURE 1064 is used.

The evaluation results of the gel fraction, the storage modulus, the initial adhesion, the heating adhesion, and the contamination of the adhesive layer of the samples obtained in the above Examples and Comparative Examples are shown in Table 1. In Table 1, each deployment amount represents relative connection The branch polymer is 100 parts by weight by weight.

In Table 1, the residue of Comparative Example 3 with ^* can be seen as a paste residue.

Claims (12)

An adhesive tape for re-peeling, which is characterized in that it has a heat-resistant film substrate and a hardened adhesive layer is provided on one surface of the heat-resistant film substrate, and the hardened adhesive layer is made of The adhesive layer formed by the adhesive composition is photocured, and the adhesive composition is obtained by graft-polymerizing a chain containing a monomer having a cyclic ether group onto a (meth)acrylic polymer. 100 parts by weight of the graft polymer contains 0.15 to 4.0 parts by weight of a photocationic polymerization initiator. The adhesive tape for re-peeling of claim 1, wherein the above-mentioned adhesive composition further contains an isocyanate-based crosslinking agent. The adhesive tape for re-peeling of claim 1, wherein the adhesive composition further contains 5 to 100 parts by weight of the epoxy resin and/or oxetane resin with respect to 100 parts by weight of the graft polymer. The adhesive tape for re-peeling of claim 1, wherein the hardened adhesive layer has a gel fraction of 80 to 99%. The adhesive tape for re-peeling of claim 1, wherein the (meth)acrylic polymer contains 0.2 to 10% by weight of a monomer having a hydroxyl group as a monomer with respect to the total amount of the (meth)acrylic polymer unit. The adhesive tape for re-peeling of claim 1, wherein the graft polymer is graft-polymerized in the presence of 0.02 to 5 parts by weight of the peroxide by 100 parts by weight of the (meth)acryl-based polymer. It is obtained by 2 to 50 parts by weight of a monomer containing a cyclic ether group and 5 to 50 parts by weight of other monomers. The adhesive tape for re-peeling of claim 1, wherein the photocationic polymerization is carried out The starting agent is a photoacid generator. The adhesive tape for re-peeling of claim 7, wherein the photoacid generator is dissolved without causing a precipitate when the solvent is made into ethyl acetate and adjusted to a concentration of 10%. The adhesive tape for re-peeling of claim 1, wherein the hardened adhesive layer has a storage modulus of from 9.0 × 10 ⁴ to 1.0 × 10 ⁶ Pa at 23 ° C. The adhesive tape for re-peeling of claim 1, wherein the heat-resistant film substrate is selected from the group consisting of polyethylene terephthalate, polyimide, aromatic polyamine, polyethylene naphthalate, and poly a group of phenyl sulfides. The adhesive tape for re-peeling of claim 1, wherein the adhesive layer is formed by a thickness of 0.5 to 100 μm. A method for producing an adhesive tape for re-peeling, which is used for producing a re-peelable adhesive tape comprising a cured adhesive layer on one side of a heat-resistant film substrate, the method comprising: bonding an adhesive a step of applying a layer of an adhesive layer on a single surface of a heat-resistant film substrate, the adhesive composition being graft-polymerized on a (meth)acrylic polymer containing a single ring-containing ether group 100 parts by weight of the graft polymer obtained by the chain of the body contains 0.15 to 4.0 parts by weight of the photocationic polymerization initiator; and a step of irradiating the adhesive layer with light to cure the light.