KR950006912B1 - Pressure sensitive adhesive composition sheet, label and laminate using it - Google Patents

Abstract

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Description

Pressure-sensitive adhesive compositions and adhesive sheets, labels and laminates using the same

The present invention relates to a laminate in which sheets are attached to a molded article by a pressure-sensitive adhesive composition that is excellent in novel blister resistance and re-peelability and does not corrode an adherend. More specifically, the present invention is a material which is excellent in cohesion and heat resistance, and which can prevent the occurrence of blisters such as swelling or rising when affixed to the surface of various adherends, or does not cause contamination, for example. Pressure-sensitive adhesive composition suitably used for surface protection sheet excellent in peelability, polyester tape for electrical insulation which does not corrode metals such as copper wire, and adhesive sheet excellent in blister resistance obtained by using this pressure-sensitive adhesive. And labels and laminates.

Conventionally, the adhesive sheets which apply | coated normal adhesive are convenient in being attached immediately by just pressing, and a solvent-free and pollution-free point are convenient, and it is used widely in many fields.

In particular, in recent years, as the number of plastic products has been increased in response to the request for the weight reduction of the products, the use of these adhesive sheets as labels on plastic products or plastic packaging cases of products has increased, and polycarabo Adhesive sheets are often affixed to the nate resin plate for surface damage protection and sunshine adjustment.

However, when the adhesive sheet or label using a gas barrier film such as conventional polyester as a substrate is attached to a molded article such as acrylic resin or polycarbonate resin, the sheet or label and the resin adherend In many cases, so-called blisters, such as foaming, swelling, or floating, are generated. In particular, this phenomenon is remarkable under high temperature and high temperature and high humidity.

The occurrence of blisters as described above causes not only the appearance deterioration but also the label falling off when affixed as a label, especially in the case of a transparent label, the pressure-sensitive adhesive is peddled or cloudy. The reality is that the appearance is not damaged.

In addition, in various products such as metal plates and glass products such as stainless steel plates, aluminum plates and steel sheets, or resin molded products such as ABS plates, acrylic resin plates and styrene resin plates, the surface may be prevented from melting or contaminating. For the purpose, the surface protection sheet which apply | coated the pressure-sensitive adhesive agent on the support body which consists of paper or synthetic resin film is used a lot.

Conventionally, as this type of surface protective sheet, for example, a paper or synthetic resin film is used as a support, and a pressure-sensitive adhesive mainly coated with natural or synthetic rubber tackified as a resin material is used. However, although the pressure-sensitive adhesive used for this surface protective sheet can reduce the initial adhesive force required for re-peelability, a state adhesive force rises remarkably with time, As a result, this sheet peels very much from a to-be-protected plate Not only is it difficult to do it, but also it is inferior in weather resistance, so that the adhesive often remains on the protected plate.

On the other hand, acrylic pressure-sensitive adhesives have been widely used for the above surface protection sheets in recent years because of their good weather resistance. Since the acrylic pressure-sensitive adhesive is required to be easily re-peeled and excellent in non-pollution to the protective plate for use in the surface protective sheet, it is necessary to increase the internal cohesion force of the adhesive and have a carboxyl group as a functional group. The copolymer with the monomer is crosslinked with a polyisocyanate compound, a melamine resin, a metal salt, etc. as an external replacement, and has been put into practical use as a surface protective sheet.

However, since such an acrylate pressure sensitive adhesive has a low crosslinking speed and it is difficult to lower the initial adhesive strength immediately after processing, it is necessary not only to age at room temperature or under heating for a long time, but also by using an air using a carboxyl kimono. Since it is coalescing, the state adhesive force rises, re-peelability from a to-be-protected plate is bad, and it has a fault, such as being hard to peel off.

It is also known to add a surfactant, silicone, plasticizer, or inorganic salt to the pressure-sensitive adhesive for the purpose of preventing the increase in the state adhesive force, but this is caused by the bleeding of this additive. It is contaminated, resulting in defects in printing or paint peeling off.

In addition, polyisocyanate compounds are often used as external crosslinking agents in copolymers in which two or more kinds of monomers having functional groups, for example, carboxyl groups, methylol groups, glycidyl groups, etc. are used together for the purpose of increasing the speed of crosslinking and improving processing efficiency. It is known to crosslink using a melamine resin, a metal salt, etc., to raise a crosslinking density, and to raise cohesion force. However, in this pressure-sensitive adhesive, the anchoring force to a support such as paper or a synthetic resin film is insufficient, and as a result, electrodeposition of the adhesive to the to-be-protected plate occurs, or the cohesive force is too high, and thus the adhesive force is insufficient. It has a problem such as peeling off or floating during processing to the to-be-protected plate.

As mentioned above, the conventional pressure-sensitive adhesive for surface protection sheets was not able to fully satisfy the balance between non-pollution and adhesive re-peelability to the to-be-protected plate.

On the other hand, as industrially valuable polyester tape for electrical insulation, it is necessary to be excellent in adhesive strength, creep characteristics and solvent resistance, but in recent years, the miniaturization, light weight, high performance of electrical and electronic devices are increasingly achieved, and in terms of performance, There is a need for a tape that is excellent in corrosiveness (non-corrosion, copper non-chromic). Conventionally, polyester tapes for electrical insulation using acrylic pressure-sensitive adhesives have been mainly used in the type of the main type that has suppressed the use of monomers containing extreme carboxyl groups or hydroxyl groups in consideration of the balance of adhesive strength, creep characteristics and weather resistance. This sufficiently excellent adhesive tape has not been found yet.

The present invention overcomes the drawbacks of such a conventional pressure-sensitive adhesive, and (1) prevents the occurrence of so-called blisters such as rising and foaming when attached to a plastic molded plate, especially a polycarbonate plate. (2) The above excellent adhesiveness which can provide the adhesive sheet which has a moderate initial adhesive force, the rate of increase of state adhesive force is low, and can provide the surface protection sheet excellent in the re-peelability which does not produce contamination. In addition to its properties, it is excellent in creep resistance and solvent resistance, and has a pressure-sensitive adhesive composition having excellent characteristics such as providing an electrical insulating tape and sheet having good corrosion resistance, and adhesion using the pressure-sensitive adhesive composition. It is an object to provide sheets and labels and laminates.

The present inventors have intensively researched to develop a pressure-sensitive adhesive composition having the above excellent characteristics. As a result, the acrylic copolymer using a carboxyl group-containing monomer is reduced in pressure for the purpose of improving the cohesion force, the heat resistance, and the adhesive force. Although it is used as a main component of the adhesive composition, such a pressure-sensitive adhesive composition is caused by this carboxyl group-containing monomer, and (1) blistering occurs due to lack of adhesion at high temperature and high humidity and lack of wetness to the adherend. Brings about. (2) The re-peelability is poor due to the increase in state adhesive force. (3) It is easy to corrode an adherend. It is found that the object can be attained by a composition having an undesirable property such as an acrylic copolymer containing no carboxyl group and using an acrylic monomer having a special functional group as a main component. Based on the knowledge, the present invention has been completed.

That is, the present invention, general formula

Unsaturated represented by (wherein R is a hydrogen atom or a methyl group, R ¹ and R ² are each a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, which may be the same as or different from each other and n is an integer of 1 to 4). 0.1-20 weight of (A) component which consists of at least 1 sort (s) of unsaturated monomer chosen from monomer,

General formula

In the unsaturated monomer represented by (wherein Y is an organic group having a radical polymerizable unsaturated bond, R ³ , R ⁴ and R ⁵ are each an aryl group, an alkyl group, or a substituted alkyl group, which may be the same as or different from each other). 0.01-10 weight of (B) component which consists of at least 1 sort (s) of unsaturated monomer chosen,

General formula

At least one unsaturated monomer selected from unsaturated monomers represented by (wherein R ⁶ , R ⁷ , R ⁸ , R ⁹ and R ¹⁰ are each hydrogen or -CH ₂ OH, which may be the same or different); (C) component consisting of 0 to 10% by weight and

General formula

Obtained by superposing | polymerizing 60-99.89 weight% of (D) component which consists of at least 1 sort (s) of unsaturated monomer selected from the unsaturated monomer represented by R <^11> is a hydrogen atom or a methyl group, R <^12> is a C1-C14 alkyl group in formula. It is to provide a pressure-sensitive adhesive composition composed mainly of an acrylic copolymer.

Moreover, this invention provides the adhesive sheet which apply | coated the said pressure-sensitive adhesive composition to a base material.

The present invention also provides a label formed by applying the pressure-sensitive adhesive composition to a label base material.

Moreover, this invention provides the laminated body which laminated | stacked the sheets and the plastic molded article via the adhesive bond layer which consists of said pressure-sensitive adhesive composition.

Hereinafter, the present invention will be described in detail.

First, the pressure-sensitive adhesive composition of the present invention will be described.

The (A) component which is the functional monomer of the present invention is an unsaturated monomer represented by the general formula (1), but preferably, R in the formula is a hydrogen atom or a methyl group, R ¹ and R ² are each a hydrogen atom or C 1 to 2 It is an alkyl group of n, and n is an unsaturated monomer which is an integer of 2-3.

Specific examples of the component (A) include, for example, N, N-dimethylaminoethyl acrylamide, N, N-dimethylaminoethyl acrylamide, N-methylaminoethyl acrylamide, aminoethyl acrylamide, and N-ethylaminoethyl acryl. Methacrylamide having a methyl group introduced into the α carbon of amide, N, N-dibutylaminoethyl acrylamide, N, N-dimethylaminopropyl acrylamide, N, N-diethylaminopropyl acrylamide, and these acrylamides And N, N-dimethylaminoethyl acrylamide, N, N-dimethylaminopropyl acrylamide, N, N-diethylaminoethyl acrylamide, N, N-diethylaminopropyl acrylamide, N, N-dimethylaminoethyl methacrylamide, N, N-dimethylaminopropyl methacrylamide, N, N-diethylaminoethyl methacrylamide, N, N-diethylaminopropyl methacrylamide.

These unsaturated monomers may be used individually by 1 type, and may be used in combination of 2 or more type.

The unsaturated monomer of such a component (A) exhibits a catalytic effect when crosslinking the acrylic copolymer of the present invention using a crosslinking agent as described later. In addition, the component (A) provides the copolymer with an elongation not shown in the acrylic copolymer containing a functional monomer conventionally used, ie, a carboxyl group-containing monomer, a hydroxyl group-containing monomer, an epoxy group-containing monomer, and the like as described above. At the same time, it has the effect of preventing the deterioration of the adhesive force at the time of high temperature and high humidity to provide a polymer having good blister resistance.

The content rate of (A) component is 0.1-20 weight%. If the component (A) is less than 0.1% by weight, the amount of use thereof is too small to fully exhibit the effect, and when the amount is greater than 20% by weight, the adhesive strength is too low to be used as an adhesive for an anti-blister, and the alkali component is too strong, so metals Easy to corrode

Moreover, the content rate of (A) component differs in the preferable range according to the use of the pressure-sensitive adhesive composition of this invention, As an adhesive for blisters, Preferably it is 2.5-15 weight%, Especially preferably, it is 2.5-10 It is weight%, As surface protection, Preferably it is 1-10 weight%, Especially preferably, it is 1-5 weight%. Moreover, as for electrical insulation, Preferably it is 0.1-5 weight%, Especially preferably, it is 0.5-3 weight%.

In addition, (B) As the component, but the number of the reactive unsaturated monomer of the general formula 2 includes widely, inter alia (b ₂ shown by (b ₁₎ component, the formula 6 represented by the following general formula 5, ) and the reactive unsaturated monomer deulsu two kinds of components as most representative, in particular (b ₁₎ component are preferable.

In addition, in said each formula, R <^13> is a hydrogen atom or a methyl group, Ph is a phenylene group, and R <^14> -R <^16> is an aral group, an alkyl group, a substituted alkyl group, a hydroxyl group, C1-C6 of an alkyl group or a substituted alkyl group is mentioned. It is preferable that it is it, and it is especially preferable that at least 1 has a hydroxyl group. Further, these (b _1), (b ₂₎ a reactive monomer represented by the component or the like, (meth) the copolymerization of the acrylic acid alkyl ester-based monomer, in order to adjust the copolymerization, may be used as a salt, such as an appropriate hydrochloride have.

(b _1), examples of preferred embodiments of the components, for example 1,1-dimethyl-1- (2-hydroxypropyl) amine methacrylate imide, 1,1-dipropyl-1- (2-hydroxypropyl) Amine methacrylimide, 1,1-dimethyl-1- (2,3-dihydroxypropyl) amine meth acrylimide, 1,1-dipropyl-1- (2-hydroxybutyl) amine acrylimide , 1,1-dimethyl-1- (2-hydroxyoctyl) aminemethacrylimide, 1,1-dimethyl-1- (2-hydroxy-3-phenoxypropyl) aminemethacrylimide, 1, 1-dimethyl-1- (2-hydroxy-3-methoxypropyl) amine methacrylimide, and 1,1-dimethyl-1- (2-hydroxy-2-phenylethyl) amine methacrylimide And 1,1-dimethyl-1- (2-hydroxypropyl) amine methacrylimide and 1,1-dimethyl-1- (2,3-dihydroxypropyl) amine methacryl. Imide.

Preferred specific examples of the component (b ₂ ) include, for example, 1,1-dimethyl-1- (2-hydroxypropyl) amine 4-isopropenylphenizide and 1,1-dimethyl-1- (2-hydroxy Hydroxy-3-phenoxypropyl) amine 4-vinyl pentimide etc. are mentioned, Especially preferably, it is 1, 1- dimethyl- 1- (2-hydroxypropyl) amine 4-isopropenyl phenylimide.

The unsaturated monomers of these (B) components may be used individually by 1 type, and may be used in combination of 2 or more type.

Although the said (B) component unsaturated monomer acts as a crosslinking component, it can provide the acryl-type copolymer which has a quick crosslinking speed, the rise of state adhesive force is small, and is easy to re-peel, but it is especially common with (A) component, It is more effective.

As an external crosslinking agent, when an isocyanate type compound and an epoxy type compound are used, it is especially advantageous by the catalytic action of (A) component monomer.

The content rate of (B) component monomer is the range of 0.01-10 weight%. When the component (B) is less than 0.01% by weight, blistering and re-peeling defects occur due to lack of cohesion, and when it exceeds 10% by weight, the cohesive force becomes too high and the decrease in adhesive force becomes significant.

Moreover, the content rate of (B) component differs in the preferable range according to the use of the pressure-sensitive adhesive composition of this invention, As an adhesive for anti-blister, Preferably it is 0.05-5 weight%, Especially preferably, it is 0.2-3 It is weight%, As for surface protection, Preferably it is 0.5 to 8 weight%, Especially preferably, it is 0.5 to 5 weight%, As for electrical insulation, Preferably it is 0.5 to 3 weight%, Especially preferably 1 to 1 2% by weight.

(C) component is an unsaturated monomer represented by General formula (3). As a specific example of (C) component, diacetone acrylamide, hydroxymethyl diacetone acrylamide, etc. are mentioned, for example, Preferably it is diacetone acrylamide.

The unsaturated monomers of these (C) component may be used individually by 1 type, and may be used in combination of 2 or more type.

When the unsaturated monomer is contained in the copolymer, it has a property of containing gas generated. Therefore, when the plastic film or the like used as the base sheet of the adhesive sheet becomes a barrier layer of the trace gas generated between the adhesive layers, There is no place to escape, and it is beneficial to prevent the formation of blisters as bubble spots of gas.

The content rate of (C) component is 0-10 weight%, Preferably it is 0.01-10 weight%, Especially preferably, it is 1-5 weight%. When the usage-amount of (C) component exceeds 10 weight%, since cohesion force becomes too high and adhesive force falls, it is unpreferable.

Moreover, although (D) component is an unsaturated monomer represented by General formula 4, R <^12> in a formula is preferable a C1-C8 alkyl group.

The said (D) component is chosen as giving the adhesive polymer excellent in weather resistance, heat resistance, durability, etc.

As a specific example of (D) component, methyl acrylate, ethyl acrylate, butyl acrylate, decyl acrylate, 2-ethylhexyl acrylate, isooctyl acrylate, these methacrylates, etc. are mentioned, Preferably methyl acrylate, Ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate.

The unsaturated monomers of these (D) component may be used individually by 1 type, and may be used in combination of 2 or more type. In particular, when using two or more types in combination, a combination of methyl acrylate and 2-ethylhexyl acrylate and a combination of ethyl acrylate and butyl acrylate are preferable. As for the combination of the said methyl acrylate and 2-ethylhexyl acrylate, the former is 20-50 weight% and the latter is used at 50-80 weight%. Moreover, as for the combination of ethyl acrylate and butyl acrylate, the former is used 5-50 weight% and the latter 50-95 weight%.

The content rate of (D) component is 60-99.89 weight%, Preferably it is 67-99.84 weight%, Especially preferably, it is 80-98.3 weight%.

The said (D) component can provide the adhesive polymer excellent in weather resistance, heat resistance, durability, etc.

The acrylic copolymer of the present invention is 50% by weight each of the unsaturated monomers of component (D) with other unsaturated monomers copolymerizable with the unsaturated monomers of components (A), (B), (C) and (D). You may substitute until.

Examples of the unsaturated monomer copolymerizable include vinyl esters such as vinyl formate and vinyl acetate, acrylonitriles such as acrylonitrile, dialkyl aminoalkylene acrylates, glycidyl acrylates, hydroxyethyl acrylates and hydrates. Acrylates such as hydroxypropyl and acrylates, methacrylates such as dialkylamino alkylene methacrylates, glycidyl methacrylates, hydroxyethyl methacrylates, acetacetoxyethyl methacrylates, acrylamides , Acrylamides such as Nn-butoxymethyl acrylamide and N-methylol acrylamide, acrylic isocyanates such as ethyl isocyanate acrylate, vinylsilanes such as alkoxy vinylsilane, acrylic acid, methacrylic acid, itaconic acid, male anhydride Acrylic acids, such as acid, etc. are mentioned, Preferably vinyl acetate and glycidyl acrylate , Glycidyl methacrylate, hydroxyethyl acrylate and hydroxyethyl methacrylate.

The amount and type of these copolymerizable unsaturated monomers are determined by the purpose of use of the pressure-sensitive adhesive composition to be obtained. Moreover, when the unsaturated monomer replacing the unsaturated monomer of (D) component exceeds 50 weight%, a pressure-sensitive adhesive composition becomes hard too much, and it is unsuitable as an adhesive composition of this objective.

The acrylic copolymer of the present invention is polymerized by various polymerization methods in which unsaturated monomers of the above-mentioned (A), (B), (C) and (D) components, and optionally the unsaturated monomer copolymerizable with them are usually used. Can be prepared. For example, the main component may be a solution polymerization method performed in a solvent such as toluene, hexane or ethyl acetate, an emulsion polymerization method performed in water, or a low molecular weight applicable copolymer obtained by copolymerizing in the substantially absence of an organic solvent. It is also possible to. Moreover, what is necessary is just to add and mix what diluted with the solvent etc. if an appropriate amount of crosslinking agent is needed for said composition in order to improve weather resistance, heat resistance, and solvent resistance.

As described above, the acrylic copolymer of the present invention provides a pressure-sensitive adhesive having no blister resistance and no corrosion to metal, which is excellent in contamination-free re-peelability. Also, in order to obtain a pressure-sensitive adhesive composition excellent in weather resistance, heat resistance, and solvent resistance, a crosslinking agent of 0.01 to 10% by weight (based on 100 parts by weight of base) can be added to the acrylic copolymer obtained as described above. have.

Although it does not specifically limit as a crosslinking agent used, A polyfunctional isocyanate compound, a polyfunctional epoxy compound, and a metal chelate compound are suitable. The amount and type thereof can be appropriately determined according to the type of monomer used in the composition and the purpose of use of the composition.

The composition of the present invention can be added to general pressure-sensitive adhesive compositions such as antioxidants, ultraviolet absorbers, rosin, phenol resins, and tackifiers such as petroleum resins according to the purpose.

The pressure-sensitive adhesive composition of the present invention may be used as a pressure-sensitive adhesive as it is, or may be applied to substrates such as sheets, films, sheets, papers, or the like, or may be applied to substrates for labels. .

Although the thickness which apply | coats the pressure-sensitive adhesive composition of this invention to the base materials, such as sheets, or the base materials for labels is not specifically limited, Usually, it is 1-100 micrometers, Preferably it is 5-30 micrometers.

Moreover, in order to improve the adhesiveness with the pressure-sensitive adhesive composition, the surface of the base material of sheets is preferably subjected to surface treatment such as corona discharge treatment, plasma treatment or primer.

In addition, the pressure-sensitive adhesive composition of the present invention can be used as an adhesive layer, and sheets and plastic molded articles can be laminated through the adhesive layer.

Although the thickness of the adhesive layer of this invention is not specifically limited, What is necessary is just to depend suitably according to a required characteristic, Usually, it is the range of 1-100 micrometers, Preferably it is the range of 5-30 micrometers.

The sheets used in the present invention include various sheets such as plates, films, sheets, and papers, but plastic sheets are preferable, and plastic sheets having transparency are particularly preferable.

The material of the plastic sheets is not particularly limited, and various plastics may be mentioned, for example, polyolefin resins such as polyethylene and polypropylene, chlorine-containing polyolefins such as polyvinyl chloride, aromatic vinyl resins such as polystyrene, and polystyrene. Acrylic resins, such as methyl methacrylate, polycarbonate resin, polyester resins, such as polyethylene terephthalate, a polyarylate resin, a polyether resin, etc. are mentioned, Polyethylene terephthalate is preferable.

In addition, these plastic sheets may be a single layer or a multilayer. In addition, these plastic sheets may use those which have been subjected to metal deposition such as aluminum or copper, surface coating or dyeing of dyes, or the like.

Moreover, what is necessary is just to select the thickness of this sheet suitably according to the characteristic requested | required, Usually, the range of 5-250 micrometers is used, Preferably it is the range of 15-80 micrometers.

Moreover, as a plastic molded article used in this invention, molded articles of various shapes are mentioned, for example, a film, a sheet, a board, a packaging container, a bottle, a sealing etc. are mentioned.

The material of these plastic molded articles is not particularly limited, and various plastics are adapted. However, from the object of the present invention, those made of a radioactive resin that generates a small amount of gas for a long time are suitable.

There are various kinds of gas-dispersible resins as described above, but in particular, examples of high blister generation include resins containing 5 mol% or more, particularly 15 mol% or more of aromatic rings such as styrene resins and polycarbonate resins, And acrylic resins such as polymethyl methacrylate, and polyolefin resins such as polyethylene immediately after molding.

The styrene-based resin used herein refers to a styrene monomer in which at least 10% by weight, in particular 30% by weight, of a raw material is used, for example, polystyrene resin, impact-resistant polystyrene resin, acrylonitrile-butadiene-styrene resin, acryl Nitrile-styrene resin, metal methacrylate-butadiene-styrene resin, acryl rubber-acrylonitrile-styrene resin, acrylonitrile-ethylene propylene rubber-styrene resin, acrylonitrile-chlorinated polyethylene-styrene resin, noryl resin, etc. It corresponds to this and it is thought that these disperse | distribute the gas of the styrene monomer after shaping | molding, and are causing a blister.

On the other hand, even if it does not contain a styrene monomer unit, since the resin which contains 5 mol% or more of aromatic rings, especially 15 mol% or more easily absorbs moisture or adsorb | sucks a low molecular weight substance, gas which becomes a cause of blister is generated. The same applies to resins having polar groups in the side chains of polymers such as acrylic resins.

Polyolefin resins such as polyethylene do not normally dissipate normal trace gases, but gas dissipation is observed immediately after molding, and even in this case, the pressure-sensitive adhesive composition of the present invention is laminated as an adhesive layer. effective.

Among these plastic molded articles, suitable are molded articles made of styrene resin such as polycarbonate resin boards for windows, polymethyl methacrylate resin boards, and casings made of styrene resin cassette tape having good transparency. When adhesive sheets are affixed to a polycarbonate resin board or a polymethyl methacrylate resin board for windows for the purpose of adjusting sunlight or preventing the occurrence of surface scratches, the formation of blisters is particularly noticeable. In addition, when blisters are generated on a label attached to a transparent styrene-based resin molded article, the blister of polystyrene cases, which are used as containers such as magnetic tapes, have become a big problem.

Therefore, it is especially effective when sheets are laminated to such a plastic molded article via the adhesive composition of this invention.

In addition, the molded article made of plastic includes not only all the plastics but also those having plastics in the surface layer of the molded article.

Although the method of manufacturing the laminated body of this invention can be performed by various methods, For example, the method of apply | coating a pressure-sensitive adhesive composition to sheets, and attaching it to a plastic molded article, a pressure-sensitive adhesive composition to a plastic molded article It can carry out by methods, such as a method of apply | coating and attaching sheets to it.

In addition, the surface of the sheet or plastic molded article is preferably subjected to surface treatment such as corona discharge treatment, plasma treatment, primer, or the like in order to improve adhesion with the pressure-sensitive adhesive composition.

As the use of these laminates, there are various uses, and in particular, window glass, a case of a cassette tape, and the like are useful.

Next, although an Example demonstrates this invention still in detail, this invention is not limited at all by these examples.

Example 1

Butyl acrylate 60 parts by weight

40 parts by weight of ethyl acrylate

3 parts by weight of N-N-dimethylaminopropyl acrylamide

Expression

1 part by weight of unsaturated unit represented by

0.5 parts by weight of 2,2'-azobis isobutylonitrile

Each component was dissolved in 90 parts by weight of ethyl acetate and 20 parts by weight of n-hexane, and then polymerized at 12 ° C. for 12 hours with stirring to obtain a high viscosity solution. 50 parts by weight of toluene was further added and diluted with this to obtain a solution of an acrylic copolymer. The polymerization rate was 98%, the viscosity 25000 cps, and the solid content 38.5%.

Example 2

2 parts by weight of coronate h (polyfunctional isocyanate compound manufactured by Nippon Polyurethane Co., Ltd.) was added to 100 parts by weight of the polymer solution of Example 1 to obtain a pressure-sensitive adhesive composition.

Example 3

To 100 parts by weight of the polymer solution of Example 1, 0.25 parts by weight of adecarazine EP-4100E (a polyfunctional epoxy compound manufactured by Asahi Kogyo Co., Ltd.) was added and mixed to obtain a pressure-sensitive adhesive composition.

Example 4

60 parts by weight of 2-ethylhexyl acrylate

30 parts by weight of methyl acrylate

10 parts by weight of vinyl acetate

3 parts by weight of N-N-dimethylaminopropyl methacrylamide

Expression

1.2 parts by weight of unsaturated monomer represented by

0.3 part by weight of 2,2'-azobis isobutylonitrile

The above components were dissolved in 90 parts by weight of ethyl acetate and 20 parts by weight of n-hexane, and the polymerization method was carried out in the same manner as in Example 1 to obtain a pressure-sensitive adhesive composition having a polymerization rate of 97%, a viscosity of 9300 CP and a solid content of 38.2%. To 100 parts by weight of this solution, 0.25 parts by weight of adeca resin EP-4100E (a multifunctional epoxy compound manufactured by Asahi Kogyo Co., Ltd.) was added and mixed to obtain a pressure-sensitive adhesive composition.

Example 5

Butyl acrylate 60 parts by weight

40 parts by weight of ethyl acrylate

3 parts by weight of N-N-dimethylaminopropyl acrylamide

Expression

1 part by weight of unsaturated monomer represented by

Expression

3 parts by weight of unsaturated monomer represented by

0.3 part by weight of 2,2'-azobis isobutylonitrile

The above components were dissolved in 90 parts by weight of ethyl acetate and 20 parts by weight of n-hexane, and the polymerization method was carried out in the same manner as in Example 1 to obtain a pressure-sensitive adhesive composition having a polymerization rate of 98.2%, a viscosity of 21000CPS, and a solid content of 39.3%. To 100 parts by weight of this solution, 0.25 parts by weight of adeka resin EP-4100E (a multifunctional epoxy compound manufactured by Asahi Kogyo Co., Ltd.) was added and mixed to obtain a pressure-sensitive adhesive composition.

Comparative Example 1

60 parts by weight of butyl acrylate, 40 parts by weight of ethyl acrylate, and 3 parts by weight of acrylic acid were used to polymerize in the same manner as in Example 1 to obtain an acrylic copolymer solution.

2 parts by weight of coronate H was added to 100 parts by weight of the polymer solution to obtain a pressure-sensitive adhesive composition.

Comparative Example 2

0.25 weight part of adecarazine EP-4100E was added instead of the coronate h of the comparative example 1, and it mixed, and obtained the pressure-sensitive adhesive composition.

Comparative Example 3

A polymer solution was obtained in the same manner as in Example 1 except that the N, N-dimethyl aminopropyl acrylamide of Example 1 was not used. 0.25 weight part of adecarazine EP-4100E was added to this solution, and it mixed, and obtained the pressure-sensitive adhesive composition.

[Comparative Example 4]

Example 1

Polymer solution was obtained by the same method as Example 1 except not using. 0.25 weight part of adecarazine EP-4100E was added to this solution, and it mixed, and obtained the pressure-sensitive adhesive composition.

The polymer solution obtained in each Example and Comparative Example was applied on a polyester film having a thickness of 25 μm so that the coating amount was 20 ± 2 g / m 2 (thickness: 18 μm), followed by drying with hot air at 100 ° C. for 1 minute to remove the pressure-sensitive adhesive sheet. Was written.

Table 1 shows the characteristics of this pressure-sensitive adhesive sheet.

Similarly, the polymer solution obtained by each example and the comparative example was diluted with toluene, the solid content was adjusted to 20%, and directly applied to a 70 μm-thick corona treated polyethylene film so that the coating thickness was about 5 μm, It heated at 70 degreeC for 3 minutes, and aged in 50 degreeC drier for 20 hours, and obtained the surface protection sheet.

Table 2 shows the properties of the surface protective sheet.

TABLE 1

Each physical property of Table 1 was calculated | required according to the method shown next.

(1) bowtack

It measured by the J.DOW method (JIS Z-0237), and the stopped bowl number was displayed.

(2) adhesion

It peels 180 degrees and measures adhesive force by JIS Z-0237, is displayed by the number of grams per 25mm width, and the measured value after affixing 20 minutes.

(3) holding force

According to JIS Z-0237, it measured by 1 kg load at 40 degreeC, and expressed by the number of seconds until it falls. However, it ends at 18000 seconds and the sign NC indicates that there is no deviation.

(4) Blister Resistance

A pressure-sensitive adhesive sheet was applied to a transparent polycarbonate plate (2 mm thick manufactured by Japan, Japan Test Panel, Inc.), and an acrylic plate (2 mm thick manufactured by Japan, Japan Test Panel, Inc.). After standing, it was left to stand in a hot air dryer at 80 ° C. for 1 hour to observe a blister state after heating promotion.

◎… Can't see blister

○… Small bubbles are slightly seen by the magnifying glass (10 times).

? Partial bubble and swelling are seen.

×… Bubbles and swelling are visible on the entire surface.

(5) corrosive

Apply a pressure-sensitive adhesive sheet to a copper plate (manufactured by Nippon Nippon Test Panel Co., Ltd.), immediately remove it from the thermostatic bath in 50 ° C x 90% RH, peel off, and observe the presence of rust.

○… No rust.

? Slight rust.

×… Rust occurs and the surface is black.

TABLE 2

Each physical property of Table 2 was calculated | required according to the method shown next.

(1) Initial Adhesion

The surface protection sheet was affixed on # 280 pre-ground polished stainless steel plate (SUS # 304), and the 180 ° peel adhesive force after 20 minutes was expressed in grams per 25 mm width.

(2) State adhesive force

A surface protective sheet of 20 × 150 mm is attached to the stainless plate, and the back side shows 180 ° peel adhesion force from the stainless plate after irradiation for a predetermined time using a weather meter manufactured by Dongyang Science & Technology Co., Ltd. box.

(3) re-peelability

After the weather meter irradiation, the possibility of re-peeling from the stainless plate when the protective sheet was strongly peeled off from the stainless plate was examined.

○… Re-release

? The adhesive force is strong, adhesiveness breaks cohesive force, and residual is recognized a little.

×… The adhesive force is so strong that the adhesive cohesively breaks down and there is a residue.

(4) pollutant

After the weather meter irradiation, the contamination state of the stainless plate when the protective sheet was strongly peeled from the stainless plate was examined.

○… No pollution

? Slightly cloudy

×… Residue, contamination of adhesive is recognized

The pressure-sensitive adhesive composition of the present invention contains an acrylic copolymer having a special functional group as a main component, so that blisters, such as rising and foaming, occur when affixed to various resin molded articles, especially polycarbonate resin molded articles and acrylic resin molded articles. it's difficult. Moreover, since the rate of increase of state adhesive force is low, it does not produce a contamination, and is excellent in re-peelability, it is also suitable for surface protection sheets. In addition, since it is excellent in corrosion resistance, creep resistance, and solvent resistance, there is an advantage that it can be applied to an electrical insulating tape.

Claims (20)

General formula Unsaturated represented by (wherein R is a hydrogen atom or a methyl group, R ¹ and R ² are each a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, which may be the same as or different from each other and n is an integer of 1 to 4). 0.1 to 20% by weight of component (A), consisting of at least one unsaturated monomer selected from monomers General formula Unsaturated monomer represented by (wherein Y is an organic group having a radically polymerizable unsaturated bond, R ³ , R ⁴ and R ⁵ are each an aryl group, an alkyl group, or a substituted alkyl group, which may be the same as or different from each other) 0.01 to 10% by weight of component (B), consisting of at least one unsaturated monomer selected from General formula At least one unsaturated monomer selected from unsaturated monomers represented by (wherein R ⁶ , R ⁷ , R ⁸ , R ⁹ and R ¹⁰ are each hydrogen or -CH ₂ OH, which may be the same or different); (C) component 0-10% by weight and General formula Obtained by superposing | polymerizing 60-99.89 weight% of (D) component which consists of at least 1 sort (s) of unsaturated monomer selected from the unsaturated monomer represented by (wherein R <^11> is a hydrogen atom or a methyl group, R <^12> is a C1-C14 alkyl group). A pressure-sensitive adhesive composition composed mainly of acryl-based copolymers. The laminated body using the pressure-sensitive adhesive composition of Claim 1 which contains a crosslinking agent in the ratio of 0.01-10 weight part with respect to 100 weight part of acrylic copolymers in a pressure-sensitive adhesive composition. The component (A) according to claim 1, wherein the component (A) is N, N-dimethylaminoethylacrylamide, N, N-dimethylaminoethyl methacrylamide, N, N-dimethylamino propylacrylamide, N, N-diethylaminopropyl Selected from methacrylamide, N, N-diethylaminoethylacrylamide, N, N-diethylamino methacrylamide, N, N-diethylaminopropyl acrylamide, N, N-diethylaminopropyl methacrylamide Pressure-sensitive adhesive composition which is at least one unsaturated monomer. The component (B) according to claim 1, wherein the component (B) is 1,1-dimethyl-1- (2-hydroxypropyl) aminemethacrylimide, 1,1-dimethyl-1- (2,3-dihydroxypropyl A pressure-sensitive adhesive composition, characterized in that it is at least one unsaturated monomer selected from amine methacrylimide, 1,1-dimethyl-1- (2-hydroxypropyl) amine 4-isopropenylphenizide. The pressure-sensitive adhesive composition according to claim 1, wherein the component (C) is diacetone acrylamide and / or hydroxymethyl diacetone acrylamide. The component (D) is at least one unsaturated monomer selected from methyl acrylate, ethyl acrylate, butyl acrylate, decyl acrylate, 2-ethylhexyl acrylate, isooctyl acrylate and the like and methacrylates thereof. Pressure-sensitive adhesive composition. The pressure-sensitive adhesive composition according to claim 1, wherein the component (D) is a combination of methyl acrylate and 2-ethylhexyl acrylate or a combination of ethyl acrylate and butyl acrylate. The pressure-sensitive adhesive composition according to claim 1, wherein the content ratio of the component (A) is 0.1 to 15% by weight. The pressure-sensitive adhesive composition according to claim 1, wherein the content ratio of the component (A) is 0.5 to 10% by weight. The pressure-sensitive adhesive composition according to claim 1, wherein the content ratio of the component (B) is 0.05 to 8% by weight. The pressure-sensitive adhesive composition according to claim 1, wherein the content ratio of the component (B) is 0.2 to 5% by weight. The pressure-sensitive adhesive composition according to claim 1, wherein the content ratio of the component (C) is 0.01 to 10% by weight. The pressure-sensitive adhesive composition according to claim 1, wherein the content ratio of the component (D) is 67 to 99.84 wt%. The acrylic copolymer according to claim 1, wherein the acrylic copolymer is 50 weights each of other unsaturated monomers copolymerizable with the unsaturated monomers of (D) component with each of the unsaturated monomers of (A), (B), (C) and (D) component. Pressure-sensitive adhesive composition, which is substituted up to%. The adhesive sheet which apply | coated the pressure-sensitive adhesive composition of Claim 1 to a base material. The table which apply | coated the pressure-sensitive adhesive composition of Claim 1 to the base material for tables. The laminated body which laminated | stacked the sheets and the molded article made from plastics via the adhesive bond layer which consists of a pressure-sensitive adhesive composition of Claim 1. 18. The laminate according to claim 17, wherein the pressure-sensitive adhesive composition contains a crosslinking agent in a proportion of 0.01 to 10 parts by weight based on 100 parts by weight of the acrylic copolymer. The laminate according to claim 17, wherein the plastic molded article is a molded article made of polycarbonate resin, acrylic resin or styrene resin. 18. The laminate according to claim 17, wherein the molded article made of plastic is a polycarbonate resin board for windows, a polymethyl methacrylate resin, and a molded article made of styrene resin having good transparency.