JP2008045112A - Resin composition, temporarily surface-protecting adhesive, adhesive sheet, method for using the adhesive sheet and method for producing the adhesive sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin composition for forming a temporarily surface-protecting adhesive having a suitable peeling strength and less change over time of peeling strength, without showing soil on an adhered material after the peeling and further having a shortened curing time, and the temporarily surface-protecting adhesive by using the same. <P>SOLUTION: This resin composition is provided by containing a resin component and a photopolymerization initiator, without containing a polymerizable monomer or polymerizable oligomer, and substantially consisting of an acrylic resin (A) without containing any ethylenically unsaturated group and forming the temporarily surface-protecting adhesive by an active energy beam. Also, the temporarily surface-protecting adhesive containing only the acrylic resin (A) without containing the ethylenically unsaturated group substantially and obtaining by irradiating the active energy beam, and further the temporarily surface-protecting adhesive obtained by irradiating the active energy beam on the acrylic resin composition [I] mainly containing the acrylic resin (A) without containing the ethylenically unsaturated group are provided. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a pressure-sensitive adhesive for a temporary surface protective film suitable for protection of plastic products, metal products, etc., and having excellent adhesive strength and peelability, and is used for labels and sheets, for tapes, for building materials, and for packaging materials. , Adhesives for temporary surface protection adhesive sheets used for metal plates, glass plates, synthetic resin plates, laminated steel plates, etc. for electronics use, and further, the adhesive sheets, methods for using the adhesive sheets, and manufacturing of adhesive sheets It is about the method.

  The adhesive film for temporary surface protection is attached to the surface of an adherend such as a metal plate such as a stainless steel plate, an aluminum plate, or a color steel plate, an optical member such as a glass plate or a polarizing film, or a resin plate such as a plastic plate, It is used for the purpose of preventing the surface of the adherend from being contaminated or scratched during transportation, storage, processing or the like.

  In general, acrylic pressure-sensitive adhesives are often used from the viewpoint of weather resistance and transparency as pressure-sensitive adhesives for temporary surface protection films for protecting plastic plates and metal products. As an acrylic pressure-sensitive adhesive, a pressure-sensitive adhesive composition obtained by copolymerizing a (meth) acrylic acid alkyl ester monomer and a monomer containing a functional group such as a carboxyl group, a hydroxyl group, or an epoxy group is used as a polyisocyanate compound. , A melamine resin, an epoxy resin, and a cross-linked material using a cross-linking agent such as a metal chelate compound are used. In these acrylic pressure-sensitive adhesives, it is common to increase the cohesive force by using a large amount of a crosslinking agent in order to improve re-peelability and to eliminate contamination on the adherend surface after peeling.

  However, with acrylic adhesives, if the degree of cross-linking is simply increased to lower the peel strength, an increase in adhesive strength over time becomes a problem after pasting, in order to suppress the increase in adhesive strength over time. It is sufficient to improve the wettability at the initial stage of application by lowering the degree of cross-linking, but if the degree of cross-linking is lowered, the adhesive strength, especially the adhesive strength after heating, becomes stronger and the physical properties are disadvantageous in that the peelability decreases. was there.

  In addition, in the case of conventional acrylic pressure-sensitive adhesives, since many crosslinking agents are used, heat aging and curing for a certain period of time are necessary to obtain the necessary pressure-sensitive adhesive properties after coating. Has a relatively long period of time, and has had problems such as an increase in inventory and delays in delivery at the production site.

  Various studies have been made to achieve these requirements. For example, in Patent Document 1, a monomer mixture in which the content of a functional group-containing monomer that can be copolymerized in solution polymerization is up to 40% by weight is polymerized to a polymerization rate of 20% by weight or more, and further copolymerizable functional groups A method for producing a pressure-sensitive adhesive composition obtained by polymerizing a monomer divided into two or more times has been proposed. On the other hand, as a technique aiming at modification of the polymer itself, not as a polymerization method, Patent Document 2 discloses re-peeling containing an acrylate containing an alicyclic structure in the molecule and having a specific gel fraction and elastic modulus. In Japanese Patent Application Laid-Open No. H10-228867, an acrylic polymer re-peeling adhesive having a specific gel fraction by copolymerizing N, N-disubstituted (meth) acrylamide is proposed.

JP-A-5-132657 JP-A-8-143842 Japanese Patent Laid-Open No. 8-143843

However, the technique disclosed in the above-mentioned patent document is not yet satisfactory in terms of suppression of the increase in adhesive force with time and peelability (contamination resistance to the adherend), and further improvement is desired.
In addition, in order to overcome the disadvantage that the curing period is long, a method of adding a curing accelerator to shorten the curing period is also known, but the added curing accelerator improves the stain resistance of the adherend. Since it has an influence, it is not appropriate when an acrylic pressure-sensitive adhesive is used for temporary surface protection, and shortening the curing period is still an important solution.

  Therefore, in the present invention, under such a background, it has an appropriate peel strength, there is little change in peel force over time, there is no contamination of the adherend after peeling, and the curing period is further shortened. It is an object to provide a resin composition for forming a temporary surface-protecting pressure-sensitive adhesive, a temporary surface-protecting pressure-sensitive adhesive using the same, a pressure-sensitive adhesive sheet, a method for using the pressure-sensitive adhesive sheet, and a method for producing the pressure-sensitive adhesive sheet It is.

  However, as a result of intensive studies in view of such circumstances, the present inventors have obtained an acrylic resin (A) that does not contain an ethylenically unsaturated group, or an acrylic resin (A) that does not contain an ethylenically unsaturated group. Surprisingly, by irradiating active energy rays to the seemingly unpolymerizable acrylic resin composition [I], it has surprisingly good peel strength and little change in the peel force over time. In addition, there is no contamination of the adherend after peeling, and a temporary surface-protective pressure-sensitive adhesive having a much shorter curing period than that of a conventional acrylic pressure-sensitive adhesive that is further crosslinked by a crosslinking agent is obtained. As a result, they have reached the present invention.

That is, the gist of the present invention relates to the following (1) to (6).
(1) An acrylic resin (A) which does not contain a polymerizable monomer or polymerizable oligomer and contains a resin component and a photopolymerization initiator, and the resin component substantially does not contain an ethylenically unsaturated group. A resin composition for forming a temporary surface-protective pressure-sensitive adhesive with an active energy ray.
(2) Temporary surface protection characterized by substantially containing only an acrylic resin (A) containing no ethylenically unsaturated groups and obtained by irradiating the acrylic resin (A) with active energy rays. Adhesive.
(3) It is obtained by irradiating an acrylic resin composition [I] mainly containing an acrylic resin (A) containing no polymerizable monomer or polymerizable oligomer and containing no ethylenically unsaturated group with active energy rays. It is a pressure-sensitive adhesive for temporary surface protection.
(4) A pressure-sensitive adhesive sheet comprising a base material and the temporary surface-protective pressure-sensitive adhesive according to any one of claims 2 to 10.
(5) A method for using a pressure-sensitive adhesive sheet, comprising: attaching the pressure-sensitive adhesive sheet according to claim 11 to a surface of an adherend, protecting the surface of the adherend, and then peeling the pressure-sensitive adhesive sheet.
(6) An acrylic resin composition [I] mainly containing an acrylic resin (A) containing no ethylenically unsaturated groups or an acrylic resin (A) containing no ethylenically unsaturated groups is provided on a substrate. The manufacturing method of the adhesive sheet for temporary surface protection characterized by including the process of forming a laminated body, and the process of performing active energy ray irradiation to this laminated body.

  In this invention, acrylic resin composition [I] is preferable at the point which can stabilize reaction at the time of active energy ray irradiation from comprising a photoinitiator.

  Furthermore, the photopolymerization initiator is disadvantageous for curing due to oxygen hindrance on the surface, but is a self-cleaving photopolymerization initiator that is advantageous for internal crosslinking, and is less susceptible to oxygen hindrance and is suitable for curing on the surface. Use of both advantageous hydrogen abstraction type photopolymerization initiators is preferable in that a well-balanced crosslinking can be performed as the whole coating film.

  In the present invention, “temporary surface protecting” is not necessarily limited to one time, but includes repeatedly applying and removing a plurality of times.

  According to the present invention, it has an appropriate peel strength, and there is little change in peel force over time (difference between initial adhesive force and ultimate adhesive force), there is no contamination of the adherend after peeling, and the curing period is further increased. A resin composition for forming a shortened temporary surface protecting adhesive and a temporary surface protecting adhesive using the same can be obtained.

Hereinafter, the present invention will be specifically described.
The pressure-sensitive adhesive for temporary surface protection of the present invention is a resin composition [I] mainly containing an acrylic resin (A) not containing an ethylenically unsaturated group or an acrylic resin (A) containing no ethylenically unsaturated group. ] Is obtained by irradiating active energy rays.

  The acrylic resin (A) used in the present invention is not particularly limited as long as it is an acrylic resin that does not contain an ethylenically unsaturated group. Among them, as a copolymerizable monomer component, (meth) acrylic acid alkyl ester (a1) Is preferably used as a main component, and if necessary, those obtained by copolymerization with other copolymerizable monomers (a2) are preferably used.

  Examples of the (meth) acrylic acid alkyl ester (a1) include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl ( (Meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isononyl (meth) acrylate, cyclohexyl (meth) acrylate, isooctyl (meth) acrylate, n-octyl (meth) acrylate, lauryl (meth) acrylate, Aliphatic (meth) acrylic acid alkyl ester such as stearyl (meth) acrylate, aromatic (meth) acrylic acid alkyl ester such as benzyl (meth) acrylate, etc. Is preferably an aliphatic (meth) acrylic acid alkyl ester having 1 to 12 carbon atoms, and further an aliphatic (meth) acrylic acid alkyl ester having an alkyl group having 4 to 12 carbon atoms is improved in initial wettability and adhesive strength over time. It is preferable in terms of suppression. These may be used alone or in combination of two or more.

  Even when (meth) acrylic acid alkyl ester having 4 to 12 carbon atoms is mainly used as the (meth) acrylic acid alkyl ester (a1), the alkyl group has 3 or less carbon atoms ( A meth) acrylic acid alkyl ester can be used in combination as appropriate.

  Other copolymerizable monomer (a2) used as needed in addition to (meth) acrylic acid alkyl ester (a1) has one ethylenically unsaturated group and has a function other than ethylenically unsaturated group. Group-containing copolymerizable monomer (a2-1) (hereinafter may be abbreviated as functional group-containing copolymerizable monomer (a2-1)), and other copolymerization properties than (a1) and (a2-1) Monomer (a2-2) (hereinafter may be abbreviated as copolymerizable monomer (a2-2)) can be used.

  Examples of the functional group-containing copolymerizable monomer (a2-1) include a carboxyl group-containing monomer, a hydroxyl group-containing monomer, an amino group-containing monomer, an acetoacetyl group-containing monomer, an amide group-containing monomer, and a glycidyl group-containing monomer. In particular, carboxyl group-containing monomers and hydroxyl group-containing monomers are preferably used.

  Examples of the carboxyl group-containing monomer include (meth) acrylic acid, crotonic acid, maleic acid, maleic anhydride, fumaric acid, citraconic acid, glutaconic acid, itaconic acid, acrylamide N-glycolic acid, cinnamic acid, (meth) Examples include Michael adducts of acrylic acid (for example, acrylic acid dimer, methacrylic acid dimer, acrylic acid trimer, methacrylic acid trimer, acrylic acid tetramer, methacrylic acid tetramer, etc.), among which acrylic acid and methacrylic acid are preferred. Used.

  Examples of the hydroxyl group-containing monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-chloro-2-hydroxypropyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2-hydroxy -3-phenoxypropyl (meth) acrylate, diethylene glycol mono (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, N-methylol (meth) acrylamide, ethyl carbitol acrylate, tripropylene glycol mono (Meth) acrylate, 1,4-butylene glycol mono (meth) acrylate, glycerol mono (meth) acrylate, 2-hydroxyethylacryloyl Examples include phosphate, 4-butylhydroxy acrylate, caprolactone-modified 2-hydroxyethyl acrylate, 2-acryloyloxyethyl succinic acid, and allyl alcohol. Among them, 2-hydroxyethyl (meth) acrylate, 4-butylhydroxy acrylate, etc. A (meth) acrylate having a hydroxyalkyl group having 1 to 4 carbon atoms is preferably used.

  The amino group-containing monomer is preferably a primary or secondary amino group-containing monomer, and examples thereof include t-butylaminoethyl (meth) acrylate and ethylaminoethyl (meth) acrylate.

Examples of the acetoacetyl group-containing monomer include 2- (acetoacetoxy) ethyl (meth) acrylate and allyl acetoacetate.
Examples of the amide group-containing monomer include diacetone acrylamide, (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, and N-methylol acrylamide.
Examples of the glycidyl group-containing monomer include glycidyl (meth) acrylate and allyl glycidyl ether.
These functional group-containing copolymerizable monomers (a2-1) are used alone or in combination of two or more.

  Examples of the copolymerizable monomer (a2-2) include acrylonitrile, methacrylonitrile, styrene, α-methylstyrene, vinyl acetate, vinyl propionate, vinyl chloride, vinylidene chloride, alkyl vinyl ether, 2-methoxyethyl (meth). (Meth) acrylic acid ester having an ether bond such as acrylate, 2-ethoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, etc. (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, etc., vinyltoluene Vinyl pyridine, vinyl pyrrolidone, itaconic acid dialkyl ester, fumaric acid dialkyl ester, acrylic chloride, methyl vinyl ketone and the like.

  For high molecular weight purposes, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate Polyfunctional monomers such as divinylbenzene can be used in combination.

Regarding the content ratio of the copolymerizable monomer components (a1) and (a2) constituting the acrylic resin (A) not containing an ethylenically unsaturated group, (meth) is the total of the copolymerizable monomer components. The acrylic acid alkyl ester (a1) is preferably 20 to 100% by weight, and the other copolymerizable monomer (a2) is preferably 0 to 80% by weight, more preferably the (meth) acrylic acid ester (a1) is 50 to 100%. % By weight, 0 to 50% by weight of the other copolymerizable monomer (a2), particularly preferably 70 to 100% by weight of the (meth) acrylic acid ester (a1), and 0 to 30% by weight of the other copolymerizable monomer (a2). %.
In this invention, it is preferable to use (meth) acrylic-acid alkylester (a1) as a main component as a copolymerizable monomer component of acrylic resin (A) from the point of an increase suppression tendency of adhesive force with time.

  In addition, when the functional group-containing copolymerizable monomer (a2-1) is contained as the other copolymerizable monomer (a2), the functional group-containing copolymerizable monomer ( a2-1) is preferably 0.1 to 20% by weight, more preferably 0.3 to 18% by weight, and particularly preferably 0.5 to 15% by weight.

The acrylic resin (A) containing no ethylenically unsaturated group used in the present invention is produced by a method well known to those skilled in the art such as radical polymerization in an organic solvent.
Examples of the organic solvent used for the polymerization include aromatic hydrocarbons such as toluene and xylene, esters such as ethyl acetate and butyl acetate, aliphatic alcohols such as n-propyl alcohol and iso-propyl alcohol, methyl ethyl ketone, methyl Examples thereof include ketones such as isobutyl ketone and cyclohexanone.

  In addition, as a polymerization initiator used for such radical polymerization, 2,2′-azobisisobutyronitrile, 2,2′-azobis-2-methylbutyronitrile, which are usual radical polymerization initiators, Azo initiators such as 4′-azobis (4-cyanovaleric acid), 2,2′-azobis (methylpropionic acid), benzoyl peroxide, lauryl peroxide, di-t-butyl peroxide, cumene hydroper Examples thereof include organic peroxides such as oxides.

  Although the weight average molecular weight of acrylic resin (A) which does not contain the ethylenically unsaturated group obtained in this way is not specifically limited, Usually, it is 200,000-2 million, Preferably it is 300,000-1,500,000. If the weight average molecular weight is too small, the removability tends to be difficult to obtain, and if it is too large, a large amount of a diluent solvent is required, which tends to be inferior in terms of coating properties and cost.

In addition, the said weight average molecular weight is a weight average molecular weight by standard polystyrene molecular weight conversion, a column: Shodex GPC in high performance liquid chromatography ("Waters 2695 (main body)" and "Waters 2414 (detector)" by Japan Waters)). KF-806L (exclusion limit molecular weight: 2 × 10 ⁷ , separation range: 100 to 2 × 10 ⁷ , theoretical plate number: 10,000 plates / piece, filler material: styrene-divinylbenzene copolymer, filler particle size: It is measured by using three series of 10 μm).

  The glass transition temperature (Tg) of the acrylic resin (A) that does not contain an ethylenically unsaturated group is not particularly limited, but is usually 0 ° C. or lower, preferably −20 ° C. or lower. If the glass transition temperature is too high, initial adhesion cannot be obtained, and the adhesive strength tends to increase with time.

In addition, in this invention, Tg is calculated | required by following Formula using Tg of the homopolymer of each monomer component which comprises a copolymer.
1 / Tg = w1 / Tg1 + w2 / Tg2 + ... Wk / Tgk
Where Tg is the glass transition temperature of the copolymer, Tg1, Tg2,... Tgk is the Tg of the homopolymer of each monomer component, w1, w2,. ... Wk represents the molar fraction of each monomer component, and w1 + w2 +... Wk = 1.

  In the pressure-sensitive adhesive for temporary surface protection obtained by irradiating the acrylic resin (A) with active energy rays, substantially containing only the acrylic resin (A) not containing the ethylenically unsaturated group of the present invention, “Substantially containing only the acrylic resin (A)” means that the acrylic resin (A) contains other components usually less than 5%, preferably less than 3%. is there. Examples of such other components include residual monomer components and initiators during the production of the acrylic resin (A).

  Moreover, in the adhesive for temporary surface protection obtained by irradiating the acrylic resin composition [I] mainly containing the acrylic resin (A) not containing the ethylenically unsaturated group of the present invention with active energy rays And “mainly containing acrylic resin (A)” means that acrylic resin (A) not containing an ethylenically unsaturated group is the main component of resin composition [I], preferably resin Content of acrylic resin (A) component which does not contain the ethylenically unsaturated group in composition [I] is 60 weight% or more, More preferably, it is 70 weight% or more.

  Furthermore, it is preferable that the resin component in the acrylic resin composition [I] consists essentially of an acrylic resin (A) that does not contain an ethylenically unsaturated group.

  Here, “the resin component consists essentially of an acrylic resin (A) that does not contain an ethylenically unsaturated group” means that 95% by weight or more of the resin component does not contain an ethylenically unsaturated group. This means that it is an acrylic resin (A), and 97 to 100% by weight is preferably an acrylic resin (A) that does not contain an ethylenically unsaturated group. Moreover, it is preferable that resin components other than the acrylic resin (A) which does not contain an ethylenically unsaturated group also do not contain an ethylenically unsaturated group.

  Furthermore, the acrylic resin composition [I] in the present invention is characterized by not containing a polymerizable monomer or a polymerizable oligomer.

  The acrylic resin composition [I] in the present invention preferably contains a photopolymerization initiator in order to stabilize the reaction during irradiation with active energy rays.

  The photopolymerization initiator is not particularly limited as long as it generates radicals by the action of light, and an intramolecular self-cleavage photopolymerization initiator or a hydrogen abstraction photopolymerization initiator is used.

  Examples of the intramolecular self-cleaving photopolymerization initiator include 4-phenoxydichloroacetophenone, 4-t-butyl-dichloroacetophenone, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one 1- (4-Isopropylenephenyl) -2-hydroxy-2-methylpropan-1-one, 1- (4-dodecylphenyl) -2-hydroxy-2-methylpropan-1-one, 4- (2 -Hydroxyethoxy-phenyl (2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, benzoin, Benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether , Benzoin isobutyl ether, benzyldimethyl ketal, α-acyloxime ester, acylphosphine oxide, methylphenylglyoxylate, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 4-benzoyl -4′-methyldiphenyl sulfide and the like, among which 2-hydroxy-2-methyl-1-phenylpropan-1-one and 1-hydroxycyclohexyl phenyl ketone are preferred.

  Examples of the hydrogen abstraction type photopolymerization initiator include benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, 3,3′-dimethyl-4-methoxybenzophenone, 2,4,4 6-trimethylbenzophenone, 4-methylbenzophenone, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, camphorquinone, dibenzosuberone, 2-ethylanthra Examples include quinone, 3,3 ′, 4,4′-tetra (t-butylperoxycarbonyl) benzophenone, benzyl, 9,10-phenanthrenequinone, among which benzophenone, methylbenzophenone, 2,4,6- Trimethylben Phenone is preferred.

  Particularly in the present invention, the use of both a self-cleaving photopolymerization initiator and a hydrogen abstraction photopolymerization initiator improves the balance between photocrosslinking of the surface portion of the pressure-sensitive adhesive layer and internal photocrosslinking, and adhesion It is preferable in that a balance between force and cohesive force can be obtained.

  The combination of the self-cleaving type photopolymerization initiator and the hydrogen abstraction type photopolymerization initiator includes self-cleaving type 1-hydroxycyclohexyl phenyl ketone and hydrogen abstraction type benzophenone, methylbenzophenone, or 2,4,6-trimethyl. A combination of benzophenones is preferred.

  Although it does not specifically limit as content of a photoinitiator, 0.01-20 weight part with respect to 100 weight part of acrylic resin (A) which does not contain an ethylenically unsaturated group, Especially 0.05-10 It is preferable that the amount is 0.1 to 4 parts by weight. If the amount is too small, there is a tendency that the curing by irradiation with active energy rays tends to vary, and if the amount is too large, the crosslink density decreases and the removability is low. There is a tendency that it is difficult to obtain the effect.

  In addition, as a photopolymerization initiator, when a self-cleaving photopolymerization initiator and a hydrogen abstraction photopolymerization initiator are used in combination, the ratio of the self-cleavage photopolymerization initiator and the hydrogen abstraction photopolymerization initiator Is preferably 70/30 to 1/99 (weight ratio), particularly preferably 55/45 to 3/97 (weight ratio), and more preferably 45/55 to 5/95 (weight ratio). Outside this range, photocrosslinking of the surface portion becomes insufficient, and adherend contamination tends to occur.

  Further, if necessary, as an auxiliary for the photopolymerization initiator, triethanolamine, triisopropanolamine, 4,4′-dimethylaminobenzophenone (Michler ketone), 2-dimethylaminoethylbenzoic acid, 4-dimethylaminobenzoic acid. Acid ethyl, ethyl 4-dimethylaminobenzoate (n-butoxy), isoamyl 4-dimethylaminobenzoate, 2-ethylhexyl 4-dimethylaminobenzoate, 2,4-diethylthioxanthone, 2,4-diisopropylthioxan It is also possible to use Song etc. together. These can be used alone or in combination of two or more.

The acrylic pressure-sensitive adhesive of the present invention is one that is crosslinked by irradiating active energy rays instead of the conventional method of crosslinking an acrylic resin with a crosslinking agent, but has stable physical properties and good reproduction. A small amount of a crosslinking agent can also be mix | blended compared with the former at the point obtained.
That is, a resin composition containing an acrylic resin (A) not containing an ethylenically unsaturated group and a reactive crosslinking agent by blending a reactive crosslinking agent with the acrylic resin (A) containing no ethylenically unsaturated group [I] is also preferable.

  Moreover, when mix | blending the said reactive crosslinking agent, acrylic resin (A) which does not contain an ethylenically unsaturated group contains a functional group containing copolymerizable monomer (a2-1) as the structural component. Is preferred.

  The reactive crosslinking agent is not particularly limited as long as it can react with the acrylic resin (A) that does not contain an ethylenically unsaturated group. For example, an isocyanate compound, an epoxy compound, an aziridine compound, a melamine compound Etc.

  Examples of the isocyanate compound include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, hydrogenated tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, hexamethylene diisocyanate, Diphenylmethane-4,4-diisocyanate, isophorone diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, tetramethylxylylene diisocyanate, 1,5-naphthalene diisocyanate, triphenylmethane triisocyanate, and these polyisocyanate compounds and tri Examples thereof include adducts with polyol compounds such as methylolpropane, burettes and isocyanurates of these polyisocyanate compounds.

  Examples of the epoxy compound include N, N, N ′, N′-tetraglycidyl-m-xylenediamine, diglycidylaniline, 1,3-bis (N, N-glycidylaminomethyl) cyclohexane, 1,6- Hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, etherene glycol diglycidyl ether, propylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, sorbitol polyglycidyl ether, glycerol polyglycidyl ether, pentaerythritol Polyglycidyl ether, polyglycerol polyglycidyl ether, sorbitan polyglycidyl ether, trimethylolpropane polyglycidyl In addition to ether, adipic acid diglycidyl ester, o-phthalic acid diglycidyl ester, triglycidyl-tris (2-hydroxyethyl) isocyanurate, resorching ricidyl ether, bisphenol-S-diglycidyl ether, and 2 epoxy groups in the molecule And epoxy resins having at least two.

  Examples of the aziridine compounds include tetramethylolmethane-tri-β-aziridinylpropionate, trimethylolpropane-tri-β-aziridinylpropionate, N, N′-diphenylmethane-4,4′-. Bis (1-aziridinecarboxamide), N, N′-hexamethylene-1,6-bis (1-aziridinecarboxyamide) and the like can be mentioned.

  Examples of the melamine compound include hexamethoxymethyl melamine, hexaethoxymethyl melamine, hexapropoxymethyl melamine, hexabutoxymethyl melamine, hexapentylmethyl melamine, hexahexyloxymethyl melamine and the like.

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

  In the present invention, the content of the reactive crosslinking agent is preferably 0.05 to 20 parts by weight, particularly 0, with respect to 100 parts by weight of the acrylic resin (A) not containing an ethylenically unsaturated group. 0.1 to 18 parts by weight, more preferably 0.3 to 15 parts by weight. If the content is too small, the effect of adding the reactive crosslinking agent cannot be obtained, and if it is too large, there is a tendency that the unreacted crosslinking agent is likely to cause contamination.

  It is possible to use an acid catalyst such as p-toluenesulfonic acid, phosphoric acid, hydrochloric acid, ammonium chloride or the like in order to promote crosslinking, and the amount of such crosslinking accelerator added to the crosslinking agent. It is preferably 10 to 50% by weight.

  In addition, the resin composition used in the present invention may be a conventionally known filler, pigment, diluent, anti-aging agent, ultraviolet absorber, ultraviolet stabilizer, antistatic agent, etc. These additives may be added as long as the required physical properties are not impaired. These additives can be used alone or in combination of two or more. What is necessary is just to set the addition amount of these additives timely so that the desired physical property may be acquired.

  Moreover, in this invention, it is a resin composition which does not contain a polymerizable monomer or polymerizable oligomer other than the said acrylic resin composition [I], and contains a resin component and a photoinitiator, and a resin component is substantially In particular, the present invention provides a resin composition for forming a temporary surface-protective pressure-sensitive adhesive by using an active energy ray characterized by comprising only an acrylic resin (A) containing no ethylenically unsaturated group. In this embodiment, a photopolymerization initiator is an essential component. Detailed description of each component of the resin composition of this embodiment, its amount, additional components, etc. is the same as the description of the acrylic resin composition [I].

  Thus, in the present invention, the acrylic resin composition (A) containing no ethylenically unsaturated group obtained above or the acrylic resin composition mainly containing the acrylic resin (A) containing no ethylenically unsaturated group. [I] (Preferably, a resin composition [I] obtained by blending a photopolymerization initiator alone or in combination with an acrylic resin (A) containing no ethylenically unsaturated group) is irradiated with active energy rays. In this way, adhesive performance can be obtained.

  When irradiating active energy rays, as active energy rays, rays such as far ultraviolet rays, ultraviolet rays, near ultraviolet rays, infrared rays, electromagnetic waves such as X rays and γ rays, electron beams, proton rays, neutron rays, etc. can be used. However, curing by ultraviolet irradiation is advantageous from the viewpoint of curing speed, availability of an irradiation device, price, and the like.

  For ultraviolet irradiation, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, a chemical lamp, an electrodeless discharge lamp, or the like that emits light in a wavelength range of 150 to 450 nm can be used.

In the present invention, the exposure dose of the actinic energy ray is preferably from 100 to 2000 mJ / cm ^2, more 150~1500mJ / cm ^2, and particularly preferably from 180~1000mJ / cm ^2. When the irradiation amount is too small, the cohesive force is insufficient due to insufficient crosslinking, and when it is too large, the substrate and the release film tend to be deteriorated.

In the present invention, unlike the irradiation of active energy rays with respect to the active energy ray-curable pressure-sensitive adhesive composition comprising a conventional polymerizable monomer or polymerizable oligomer, an acrylic resin (A) containing no ethylenically unsaturated group, or The resin composition [I] mainly containing the acrylic resin (A) not containing an ethylenically unsaturated group is irradiated with active energy rays, and therefore, in an inert gas atmosphere in order to suppress polymerization inhibition due to oxygen. There is no need to perform or coat the coating film made of the pressure-sensitive adhesive composition with a cover film. In the present invention, the irradiation with the active energy ray is preferably performed in the presence of oxygen, and it is particularly preferable that the irradiation is performed in the atmosphere. Also, the irradiation amount of active energy is less than 1000 mJ / cm ² because the number of reaction points is reduced if the polymer of the present invention is crosslinked as compared with the case where a polymerizable monomer or polymerizable oligomer is used. An irradiation dose is sufficient.

  The temporary surface-protecting pressure-sensitive adhesive after being crosslinked by irradiation with active energy rays preferably has a gel fraction of 40 to 100% by weight, and particularly preferably 50 to 100% by weight. If the gel fraction is too small, the re-peelability tends to decrease due to insufficient cohesive force.

The gel fraction is a measure of the degree of crosslinking and is calculated by the following method.
That is, an adhesive sheet (not provided with a separator) obtained as described below is wrapped in a 200 mesh SUS wire mesh, immersed in toluene at 23 ° C. for 24 hours, and the insoluble adhesive component remaining in the wire mesh The weight percentage is taken as the gel fraction. Note that the weight of the substrate is subtracted.

  In order to adjust the gel fraction of the pressure-sensitive adhesive to the above range, the irradiation amount and irradiation intensity of the active energy rays are adjusted, and the photopolymerization initiator is different from the self-cleavage type and the hydrogen abstraction type. The two photopolymerization initiators are used in combination, and the two types of photopolymerization initiators are used in combination, and the ratio of each type is adjusted, and the amount of the photopolymerization initiator is adjusted.

  It should be noted that the irradiation amount and irradiation intensity of the active energy ray, the composition ratio of the photopolymerization initiator, and the addition amount need to be balanced because the gel fraction varies depending on the respective interactions.

  In this invention, as above-mentioned, acrylic resin (A) which does not contain an ethylenically unsaturated group, or acrylic resin composition [I] which mainly contains acrylic resin (A) which does not contain an ethylenically unsaturated group Is used to have an adhesive performance as a temporary surface protecting adhesive by irradiating an active energy ray. Specifically, for example, an acrylic resin not containing such an ethylenically unsaturated group ( A) or an acrylic resin composition [I] mainly containing an acrylic resin (A) not containing an ethylenically unsaturated group is provided on a substrate, and then an active energy ray is irradiated to form an adhesive sheet. Such an adhesive sheet is bonded to an adherend.

  In the present invention, “sheet” is not particularly distinguished from “film”, and is described as meaning including film.

  The material of the base material is not particularly limited as long as it is a material forming a sheet. For example, aluminum, copper, iron metal foil, polyethylene naphthalate, polyethylene terephthalate, boribylene terephthalate, polyethylene terephthalate / isophthalate copolymer Polyester resins such as coalescence, polyolefin resins such as polyethylene, polypropylene, polymethylpentene, polyfluorinated ethylene resins such as polyvinyl fluoride, polyvinylidene fluoride, and polyfluorinated ethylene, polyamides such as nylon 6, nylon 6,6, and poly Cellulose such as vinyl chloride, polyvinyl chloride / vinyl acetate copolymer, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, vinyl polymers such as polyvinyl alcohol and vinylon, cellulose triacetate, cellophane, etc. Resin, polymethyl methacrylate, polyethyl methacrylate, polyethyl acrylate, polybutyl acrylate and other acrylic resins, polystyrene, polycarbonate, polyarylate, polyimide and other synthetic resin sheets, fine paper, glassine paper, etc. Examples thereof include a single layer or a multilayer such as paper, glass fiber, natural fiber, and synthetic fiber.

  Among these, in consideration of price, a sheet of polyethylene terephthalate, polyethylene, polypropylene, or the like is preferably used.

  In addition, in order to increase the anchoring property of the pressure-sensitive adhesive layer to the base material, the surface of the base material is treated to improve known easy adhesion properties such as corona discharge treatment, plasma treatment, primer coating, degreasing treatment, surface roughening treatment, etc. In addition, an antistatic layer may be provided for antistatic.

  Although the thickness of the said base material is not specifically limited, Generally it is 500 micrometers or less, Preferably it is 5-300 micrometers, More preferably, the thickness of about 10-200 micrometers can be illustrated.

  The pressure-sensitive adhesive for temporary resurface protection of the present invention is provided as a pressure-sensitive adhesive sheet, and the pressure-sensitive adhesive sheet is produced, for example, by applying the resin composition of the present invention in the form of a solution on the substrate and drying it by heating. can do.

  The thickness of the pressure-sensitive adhesive layer is not particularly limited, but is generally 1 to 100 μm, preferably about 2 to 50 μm. If the thickness of the pressure-sensitive adhesive layer is too thick, the pressure-sensitive adhesive of the temporary surface protection pressure-sensitive adhesive sheet tends to remain on the surface of the adherend when it is peeled off. There is a tendency that the function as a pressure-sensitive adhesive sheet for surface protection is less likely to be achieved, for example, the adhesive strength to the adherend is reduced and peeling occurs.

  A separator can be laminated on the surface of the pressure-sensitive adhesive sheet for the purpose of protecting the temporary surface-protective pressure-sensitive adhesive layer from contamination until the temporary surface-protective pressure-sensitive adhesive sheet of the present invention is bonded to an adherend. As the separator, those obtained by releasing the synthetic resin sheet, paper, cloth, nonwoven fabric and the like exemplified in the base material can be used.

  The pressure-sensitive adhesive sheet using the temporary surface protecting pressure-sensitive adhesive of the present invention is an acrylic resin (A) that does not contain an ethylenically unsaturated group on the substrate, or an acrylic resin that does not contain an ethylenically unsaturated group. It is obtained by applying and drying an acrylic resin composition [I] mainly containing (A) and irradiating with active energy rays. When the acrylic resin (A) or the acrylic resin composition [I] that does not contain an ethylenically unsaturated group is in the form of a solution, the acrylic resin (A) that does not contain a solution-like ethylenically unsaturated group Alternatively, a direct coating method in which the acrylic resin composition [I] is directly applied to a substrate, or a solution-like acrylic resin (A) or acrylic resin composition [I] that does not contain an ethylenically unsaturated group is used as a separator. After being coated on the substrate, it is laminated on the substrate by a transfer coating method or the like to be bonded to the substrate.

  In the direct coating method, an acrylic resin (A) or an acrylic resin composition [I] is applied to a substrate, dried by heating, and then bonded to a separator. The coating is performed by a conventional method such as roll coating, die coating, gravure coating, comma coating, or screen printing.

  On the other hand, in the transfer coating method, the acrylic resin (A) or the acrylic resin composition [I] is applied to the separator and dried by heating, and then the substrate is bonded. About the coating method, the method similar to direct coating can be used.

  The pressure-sensitive adhesive sheet using the pressure-sensitive adhesive for temporary surface protection of the present invention is applied to the surface of the adherend, and then the temporary surface-protective pressure-sensitive adhesive of the present invention even if the adherend and the pressure-sensitive adhesive sheet are exposed to high temperatures. It is possible to peel the agent from the adherend.

  There are no particular limitations on the type of adherend that can be used for the temporary surface protecting adhesive of the present invention. For example, aluminum, copper, iron metal foil, polyethylene naphthalate, polyethylene terephthalate, boribylene terephthalate, polyethylene terephthalate / Polyester resins such as isophthalate copolymers, polyolefin resins such as polyethylene, polypropylene, and polymethylpentene, polyfluorinated ethylene resins such as polyvinyl fluoride, polyvinylidene fluoride, and polyfluorinated ethylene, nylon 6, nylon 6, 6, etc. Polyamides, polyvinyl chloride, polyvinyl chloride / vinyl acetate copolymers, ethylene-vinyl acetate copolymers, ethylene-vinyl alcohol copolymers, vinyl polymers such as polyvinyl alcohol and vinylon, cellulose triacetate, cellophane, etc. Cellulose-based resins, polymethyl methacrylate, polyethyl methacrylate, polyethyl acrylate, acrylic resins such as polybutyl acrylate, polystyrene, polycarbonate, polyarylate, synthetic resin sheet or plate such as polyimide.

Thus, the temporary surface protecting adhesive of the present invention is used for metal sheets, glass plates, synthetic resin plates, laminated steel plates, etc. for labels and sheets, tapes, building materials, packaging materials, and electronics. It can be suitably used as a pressure-sensitive adhesive.
And the pressure-sensitive adhesive sheet obtained by the above-mentioned temporary surface-protecting pressure-sensitive adhesive can temporarily protect the surface of the adherend by being affixed to the surface of the adherend. The pressure-sensitive adhesive sheet is peeled off from the adherend.

EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further more concretely, this invention is not limited to a following example, unless the summary is exceeded.
In the examples, “parts” and “%” mean weight basis unless otherwise specified.

[Adjustment of acrylic resin (A)]
[Acrylic resin (A-1)]
In a reactor equipped with a thermometer, stirrer, dropping funnel and reflux condenser, 50 parts of ethyl acetate and 10 parts of acetone were charged, and the temperature was raised with stirring. After reaching 70 ° C., 100 parts of 2-ethylhexyl acrylate was added to 100 parts of 2-ethylhexyl acrylate. A mixture in which 0.03 part of bisisobutyronitrile (AIBN) was dissolved was added dropwise over 2 hours. Furthermore, after polymerization for 7 hours while successively adding a polymerization catalyst solution in which 0.05 part of AIBN was dissolved in 10 parts of ethyl acetate during the polymerization, it was diluted with toluene to obtain 40% of the acrylic resin (A-1). A solution was obtained. The weight average molecular weight of the acrylic resin (A-1) was 1,000,000.

[Acrylic resin (A-2)]
In a reactor equipped with a thermometer, a stirrer, a dropping funnel and a reflux condenser, 60 parts of ethyl acetate was charged, the temperature was increased while stirring, and after reaching 75 ° C., 93 parts of 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate A mixture in which 0.03 part of azobisisobutyronitrile (AIBN) was dissolved in 7 parts was added dropwise over 2 hours. Further, polymerization was carried out for 7 hours while successively adding a polymerization catalyst solution in which 0.05 part of AIBN was dissolved in 10 parts of ethyl acetate during the polymerization, and then diluted with toluene to obtain 40% of the acrylic resin (A-2). A solution was obtained. The weight average molecular weight of the acrylic resin (A-2) was 900,000.

[Acrylic resin (A-3)]
In a reactor equipped with a thermometer, stirrer, dropping funnel and reflux condenser, 96 parts of butyl acrylate, 4 parts of 2-hydroxyethyl acrylate, 60 parts of ethyl acetate, 40 parts of acetone and azobisisobutyronitrile (AIBN) ) 0.012 part was charged, the internal temperature was raised to 75 ° C., and after 30 minutes, a polymerization initiator solution in which 0.02 part of AIBN was dissolved in 30 parts of ethyl acetate was added dropwise over about 1 hour, followed by polymerization for 1 hour. And diluted with toluene to obtain a 25% solution of acrylic resin (A-3). The weight average molecular weight of the acrylic resin (A-3) was 1,600,000.

(Reactive crosslinking agent)
The following were prepared as crosslinking agents capable of reacting with the acrylic resin (A).
Hexamethylene diisocyanate compound (Nippon Polyurethane, Coronate HX)

(Photopolymerization initiator)
The following were prepared as photopolymerization initiators.
[Self-cleaving photopolymerization initiator]
1-hydroxycyclohexyl phenyl ketone (Ciba Specialty Chemicals: Irgacure 184)
[Hydrogen extraction type photopolymerization initiator]
Mixture of 4-methylbenzophenone and 2.4.6-trimethylbenzophenone (Nippon Siebel Hegner, Inc .: ESACURE TZT)

Examples 1-4, Comparative Example 1
A resin composition solution was prepared with a blending composition as shown in Table 1.
The obtained resin composition solution was applied using a polyethylene terephthalate (PET) sheet (thickness 38 μm) as a base material so that the thickness after drying was 25 μm, and then dried at 100 ° C. for 3 minutes. After that, UV irradiation is performed with a high-pressure mercury lamp (the amount of irradiation shown in Table 1), and the release-treated PET sheet is adhered to the surface of the pressure-sensitive adhesive layer made of such a resin composition to protect it, for temporary surface protection An adhesive sheet with an adhesive was obtained.

  The following evaluation was performed about the adhesive sheet obtained by the said Example and comparative example. The release-treated PET sheet was peeled off when performing various measurement tests.

(Initial gel fraction)
After leaving the pressure-sensitive adhesive sheet obtained above for one day, the pressure-sensitive adhesive sheet is wrapped with a 200-mesh SUS wire mesh, immersed in toluene at 23 ° C. for 24 hours, and the insoluble pressure-sensitive adhesive component remaining in the wire mesh is removed. The weight percentage is the gel fraction (%). Note that the weight of the substrate is subtracted.

(Initial adhesive strength)
After leaving the pressure-sensitive adhesive sheet obtained above for one day, a test piece having a size of 25 mm × 100 mm was prepared from the pressure-sensitive adhesive sheet, and this test piece was placed on a stainless steel plate (SUS304BA plate) as an adherend at 23 ° C. Then, a 2 kg rubber roller was reciprocated in two reciprocations under an atmosphere with a relative humidity of 50%, and left for 30 minutes in the same atmosphere, and then 180 ° peel strength (N / 25 mm) (peel rate 300 mm / min) was measured.

(Achieved gel fraction)
The gel fraction (%) was measured in the same manner as in the above method except that the sample obtained from the pressure-sensitive adhesive sheet that had passed for 1 week was used.

(Achieved adhesive strength)
Adhesive strength was measured in the same manner as in the above method except that a sample obtained from a pressure-sensitive adhesive sheet that had passed for one week was used.

(Peelability (contamination resistance to adherend))
For the peelability (contamination resistance to the adherend), the pressure-sensitive adhesive sheet obtained above was allowed to stand for 1 day, and then a test piece having a size of 25 mm × 100 mm was prepared from the pressure-sensitive adhesive sheet. Each of the adherends (SUS304BA plate) was pressure-bonded by reciprocating a 2 kg roller twice, left at 70 ° C. for 5 days, and then peeled 180 ° in a 23 ° C., 50% RH atmosphere (peeling speed 300 mm / min). The state of the adherend surface was observed. As a result, no contamination was confirmed on all sheets.

  Table 2 shows the evaluation results of Examples and Comparative Examples.

In Examples 1 to 4, which were irradiated with ultraviolet rays after being applied to the base material, the gel fraction after 1 day of sheet preparation had a sufficiently high value, and the difference in adhesive strength between 1 day after sheet creation and 1 week after It is getting smaller. This indicates that the physical properties of the pressure-sensitive adhesive are stable on the first day after the sheet is formed, and by using the pressure-sensitive adhesive of the present invention, it is possible to produce a product in a short curing time.
On the other hand, in Comparative Example 1 where ultraviolet irradiation is not performed, the adhesive strength is high at the time one day after the sheet is formed, and it is difficult to use as a temporary surface protecting adhesive. Furthermore, it can be seen that as the gel fraction is greatly increased one week after the sheet is formed, the adhesive strength is greatly reduced, and it takes a long time for the physical properties of the adhesive to stabilize.

  The present invention forms a temporary surface-protective pressure-sensitive adhesive having an appropriate peel strength, little change in peel force over time, no contamination of the adherend after peeling, and a shorter curing time. Resin compositions and temporary surface protecting adhesives using the same, for labels and sheets, for tapes, for building materials, for packaging materials, for electronics, metal plates, glass plates, synthetic resin plates, It is very useful for temporary surface protecting adhesives used for laminated steel sheets.

Claims (13)

  A resin composition that does not contain a polymerizable monomer or polymerizable oligomer and contains a resin component and a photopolymerization initiator, and the resin component is substantially only from an acrylic resin (A) that does not contain an ethylenically unsaturated group. A resin composition for forming a temporary surface-protecting pressure-sensitive adhesive with active energy rays.   A temporary surface-protective pressure-sensitive adhesive characterized by substantially containing only an acrylic resin (A) containing no ethylenically unsaturated groups and obtained by irradiating the acrylic resin (A) with active energy rays .   It is obtained by irradiating an active resin to an acrylic resin composition [I] mainly containing an acrylic resin (A) that does not contain a polymerizable monomer or polymerizable oligomer and does not contain an ethylenically unsaturated group. A temporary adhesive for surface protection.   An acrylic resin obtained by polymerizing 20 to 100% by weight of (meth) acrylic acid alkyl ester (a1) with respect to the entire copolymerizable monomer component, the acrylic resin (A) containing no ethylenically unsaturated group 4. The pressure-sensitive adhesive for temporary surface protection according to claim 2, wherein the pressure-sensitive adhesive is a resin.   The pressure-sensitive adhesive for temporary surface protection according to any one of claims 2 to 4, wherein the acrylic resin (A) containing no ethylenically unsaturated group has a weight average molecular weight of 200,000 to 2,000,000.   The temporary surface-protective pressure-sensitive adhesive according to any one of claims 2 to 5, wherein the acrylic resin (A) containing no ethylenically unsaturated group has a glass transition temperature of 0 ° C or lower.   The pressure-sensitive adhesive for temporary surface protection according to any one of claims 3 to 6, wherein the acrylic resin composition [I] further contains a photopolymerization initiator.   8. The temporary surface protecting pressure-sensitive adhesive according to claim 7, wherein the photopolymerization initiator includes a self-cleaving photopolymerization initiator and a hydrogen abstraction photopolymerization initiator.   The acrylic resin composition [I] further contains a reactive cross-linking agent, and the pressure-sensitive adhesive for temporary surface protection according to any one of claims 3 to 8.   The pressure-sensitive adhesive for temporary surface protection according to any one of claims 2 to 9, wherein the gel fraction is 40 to 100% by weight.   A pressure-sensitive adhesive sheet comprising a base material and the temporary surface-protective pressure-sensitive adhesive according to claim 2.   A method for using a pressure-sensitive adhesive sheet, comprising: attaching the pressure-sensitive adhesive sheet according to claim 11 to a surface of an adherend, protecting the surface of the adherend, and then peeling the pressure-sensitive adhesive sheet.   A laminate comprising an acrylic resin (A) containing no ethylenically unsaturated groups or an acrylic resin composition [I] mainly containing an acrylic resin (A) containing no ethylenically unsaturated groups on a substrate. And a step of irradiating the laminated body with active energy rays.