JP3038542B2 - Antistatic pressure sensitive adhesive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a pressure-sensitive adhesive (adhesive). More specifically, the present invention relates to a pressure-sensitive adhesive excellent in antistatic properties and suitable for a dicing tape, a carrier tape, a surface protection sheet of a steel plate or a plastic plate, and the like.

[0002]

2. Description of the Related Art Conventionally, for example, as an adhesive tape or sheet for the purpose of preventing static electricity when peeled from an adherend, a polyether polyol compound and at least one alkali metal salt are mixed with an acrylic polymer. A pressure-sensitive adhesive on at least one surface of a substrate to form a pressure-sensitive adhesive layer (for example, JP-A-6-12853).
No. 9) and an adhesive prepared by adding an antistatic agent (anionic surfactant, cationic surfactant, nonionic surfactant, amphoteric surfactant, fluorine surfactant, etc.). A surface protective material for synthetic resin (for example, JP-A-58-191777) obtained by applying an agent to a paper base, and a quaternary ammonium salt such as lauryltrimethylammonium chloride applied to the back of the protective sheet. For example, a sheet for protecting an antistatic automobile coating film provided with an antistatic layer (for example, JP-A-6-128538) is known.

[0003]

However, in the above-mentioned method, the polyether polyol compound bleeds out of the pressure-sensitive adhesive layer over time, and contaminates the surface of an adherend, such as a stainless steel plate or a plastic plate; Alkali ions generated from the alkali metal salt compounded in the adhesive,
Halogen ions penetrate silicon wafers and cannot be used for dicing tapes and carrier tapes used in the electric and electronic fields; they also have problems such as bleed out of antistatic agents. There are problems such as contamination of the surface of the adherend due to odor, and changes in adhesive properties over time. In addition, when stored in a rolled state, lauryl trimethyl ammonium chloride and the like on the back surface migrate to the adhesive layer over time, causing contamination of the adherend by halogen ions, dicing tape, carrier tape, etc. Has a problem that it cannot be used.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that an alkyl (meth) acrylate copolymer having a specific functional group in a molecular side chain has been used. The present inventors have found that a pressure-sensitive adhesive can have excellent antistatic properties without contamination of a non-adhesive body by a low molecular compound, a metal ion and the like, and have reached the present invention. That is, the present invention relates to a compound represented by the following general formula (1):

Embedded image [Wherein, R ^{1 to} R ³ are linear or branched, saturated or unsaturated hydrocarbon groups having 1 to 11 carbon atoms (provided that R ^{1 to} R ³
Any two of the above may be bonded via O or N as necessary to form a heterocyclic ring. ) And R
⁴ represents an alkyl group having 1 to 8 carbon atoms or an aromatic hydrocarbon group, and X represents an acid group selected from a carboxylic acid group, a sulfonic acid group, a sulfamic acid group and a (phosphite) phosphate group. And a quaternary ammonium / organic acid base-containing alkyl (meth) acrylate-based copolymer (A) represented by the formula (A). A1) is an alkyl (meth) acrylate having 4 to 12 carbon atoms (a
1) comprising a polymerizable monomer (a2) having an organic acid group and, if necessary, another polymerizable monomer (a3);
(A2) is a pressure-sensitive adhesive tape or sheet obtained by applying and drying an antistatic pressure-sensitive adhesive comprising any of the following: A polymerizable monomer having a carboxylic acid group selected from the following, a monoalkyl ester of a dibasic acid (the dibasic acid is selected from maleic acid, itaconic acid and fumaric acid), 3- (meth) acryloylpropionic acid, 2-hydroxyalkyl (having 2 to 2 carbon atoms in the hydroxyalkyl group)
3) Succinic anhydride ring-opened adduct to (meth) acrylate, polyoxyalkylene (C2-C2 alkylene group)
4) Ring-opening of succinic anhydride to a ring-opened succinic anhydride adduct of glycol mono (meth) acrylate and a polyadduct of caprolactone to 2-hydroxyalkyl (2 to 3 carbon atoms of the hydroxyalkyl group) (meth) acrylate Compounds added: polymerizable monomer having a phosphorous ester group, polymerizable monomer having a sulfonic acid group, polymerizable monomer having a sulfamic acid group, and a mixture of two or more thereof.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, (A) represents, for example, the above-mentioned general formula (2) ) To react the quaternary ammonium carbonate ester salt (A2). In the above general formula, when the carbon number of any of R ^{1 to} R ³ exceeds 11, the antistatic property of the obtained pressure-sensitive adhesive becomes insufficient.

The alkyl (meth) acrylate copolymer (A1) includes, for example, an alkyl (meth) acrylate (a1) having 4 to 12 carbon atoms, a polymerizable monomer (a2) containing an organic acid group, And an alkyl (meth) acrylate copolymer comprising another polymerizable monomer (a3) if necessary.

As (a1), (meth) acrylates derived from aliphatic alcohols having 4 to 12 carbon atoms [n-butyl (meth) acrylate, 2-butyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (Meth) acrylate, octyl (meth) acrylate, 2
-Ethylhexyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, lauryl (meth) acrylate, etc.] and mixtures of two or more of these. Particularly preferred among these are n-butyl acrylate, 2-ethylhexyl acrylate and mixtures thereof.

As (a2), a polymerizable monomer having a carboxylic acid group [for example, monobasic acids such as (meth) acrylic acid and crotonic acid; dibasic acids such as maleic acid, itaconic acid and fumaric acid; Monoalkyl esters of these dibasic acids; 3- (meth) acryloylpropionic acid;
Ring-opened succinic anhydride adduct of hydroxyalkyl (2-3 carbon atoms) (meth) acrylate, ring-opened succinic anhydride adduct of polyoxyalkylene (2-4 carbon atoms) glycol mono (meth) acrylate, 2 A compound obtained by ring-opening addition of succinic anhydride to a caprolactone polyadduct to hydroxyalkyl (2 to 3 carbon atoms) (meth) acrylate), a polymerizable monomer having a (sub) phosphite ester group [eg, , (Meth) acryloyloxyethyl acid phosphate, (meth) acryloyloxypropyl acid phosphate, (meth) acryloyloxy-
2-hydroxypropyl acid phosphate, (meth) acryloyloxy-3-hydroxypropyl acid phosphate, (meth) acryloyloxy-3-
Chloro-2-hydroxypropyl acid phosphate, allyl alcohol acid phosphate, (meth)
Acryloyloxyethyl acid phosphite, etc.), a polymerizable monomer having a sulfonic acid group (for example,
Vinylsulfonic acid, styrenesulfonic acid, 2-acrylamide-2-methylpropanesulfonic acid, isethionic acid (meth) acrylate, etc.), and a polymerizable monomer having a sulfamic acid group [for example, N-hydroxyethyl-N
-[2- (meth) acryloyloxyethyl] sulfamic acid, N, N-bis [2- (meth) acryloyloxyethyl] sulfamic acid, (meth) acryloyl isocyanate and N, N-di (2-hydroxyethyl) sulfamine Acid adduct) and mixtures of two or more of these. Preferred of these are:
(Meth) acrylic acid, maleic acid, itaconic acid, (meth) acryloyloxyethyl acid phosphate,
2-acrylamido-2-methylpropanesulfonic acid,
Isethionic acid (meth) acrylate, N-hydroxyethyl-N- [2- (meth) acryloyloxyethyl]
Adducts of sulfamic acid and (meth) acryloyl isocyanate with N, N-di (2-hydroxyethyl) sulfamic acid, and particularly preferred are (meth) acrylic acid, (meth) acryloyloxyethyl acid phosphate, Acrylamido-2-methylpropanesulfonic acid and N-hydroxyethyl-N- [2-
(Meth) acryloyloxyethyl] sulfamic acid.

The (a3) includes a monomer (a3-1) having a reactive functional group and a monomer (a3-2) having no reactive functional group. The above (a3-
Examples of 1) include, for example, a monomer having a hydroxyl group [2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, polyoxyalkylene (having 2 to 2 carbon atoms). 4) Glycol mono (meth) acrylate, etc.], amide group-containing monomer [(meth) acrylamide, etc.], amino group-containing monomer [N, N-dimethylaminoethyl (meth) acrylate, etc.], methylol And monomers having a group [N-methylolacrylamide and the like].

The (a3-2) includes, for example, (meth) acrylic acid esters of alcohols having an alkyl group having 1 to 3 carbon atoms [methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate; ) Acrylate, etc.], wherein the carbon number of the alkyl group is 13 to
(Meth) acrylic acid esters of 18 alcohols [tridecyl (meth) acrylate, myristyl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, etc.], (meth) acrylic acid esters of alicyclic alcohols [cyclohexyl] (Meth) acrylate, etc., aromatic alcohol (meth) acrylate [benzyl (meth) acrylate, etc.], aromatic monomer [styrene, vinyltoluene, etc.], allyl compound [allyl acetate, etc.], having a nitrile group Monomer [(meth) acrylonitrile, α-chloro (meth) acrylonitrile, etc.), halogen-containing monomer [vinyl chloride, vinylidene chloride, etc.], vinyl ester monomer [vinyl acetate, vinyl propionate, vinyl butyrate, Vinyl versatate], Ether-based monomers [vinyl ethyl ether, vinyl propyl ether, and vinyl isobutyl ether] may be mentioned such.

Among the preferred examples of (a3), among (a3-1), a monomer having a hydroxyl group and a polymerizable monomer having an amide group are preferable. -Hydroxyethyl (meth) acrylate and (meth) acrylamide. Among (a3-2), vinyl ester-based polymerizable monomers and aromatic polymerizable monomers are preferred, and particularly preferred are vinyl acetate, vinyl propionate, and styrene. In the above (a3), two or more kinds can be used in combination.

The weight ratio of (a1), (a2) and (a3) constituting (A1), (a1) :( a2) :( a3) is:
Normal (30-99.8): (0.2-30): (0-4
0), preferably (50-98): (0.5-25):
(0 to 30), particularly preferably (65 to 96): (1 to 30)
20): (0 to 20). If the ratio of (a1) is less than 30, tack and adhesive strength will be insufficient, and if it exceeds 98.8, cohesive strength will decrease. If the ratio of (a2) is less than 0.2, the cohesive strength decreases, and if it exceeds 30, the tack and adhesive strength decrease. On the other hand, if the ratio of (a3) exceeds 40, tack and adhesive strength decrease.

The above-mentioned general formula (2) which is reacted with an organic acid group of the above alkyl (meth) acrylate copolymer (A1)
The quaternary ammonium carbonate ester salt represented by
2) can be produced by reacting a tertiary amine with a dialkyl carbonate or diaryl carbonate having 1 to 8 carbon atoms.

The tertiary amine used in the production of the above (A2) includes aliphatic amines [trimethylamine, triethylamine, tri-n-propylamine, tri-n-amine].
Butylamine, tri-n-octylamine, diethyl-
1-propylamine and the like]; heterocyclic amines [N-methylpyrrolidine, N-ethylpyrrolidine, N-methylpiperidine, N-ethylpiperidine, N-methylhexamethyleneimine, N-ethylhexamethyleneimine, N-methyl Morpholine, N-butylmorpholine, N, N′-dimethylpiperazine, N, N′-diethylpiperazine,
1,5-diazabicyclo [4,3,0] nonene-5,
1,8-diazabicyclo [5,4,0] undecene-
7, pyridine, 4-dimethylaminopyridine, picolines, 1-methylimidazole, 1,2-dimethylimidazole, 1,4-dimethyl-2-ethylimidazole,
1,2-dimethylimidazoline, 1,2,4-trimethylimidazoline, 1,4-dimethyl-2-ethylimidazoline and the like]; and a mixture of two or more of these. Among these, preferred are trimethylamine, triethylamine and tri-n-butylamine among aliphatic amines; and 1,5-diazabicyclo [4,3,0] nonene-5 among alicyclic amines;
1,8-diazabicyclo [5,4,0] undecene-7
And 1,2,4-trimethylimidazoline.

The dialkyl carbonate (C1-8) ester used in the production of (A2) includes dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, dipropyl carbonate and the like, and the diaryl carbonate includes diphenyl carbonate and the like. Is mentioned. Of these, preferred are dialkyl carbonates, and particularly preferred is dimethyl carbonate.

The molar ratio of the tertiary amine to the carbonic acid diester in the production of the above (A2) is usually 1: (0.3 to 0.3).
4), preferably 1: (0.5 to 2), more preferably 1: (1 to 1.5), particularly preferably 1: (1 to 1.5).
To 1.1). During the reaction, a reaction solvent [methanol, ethanol, etc.] may be used if necessary. The reaction temperature is usually 30 to 150 ° C, preferably 50 to 100 ° C.
° C.

The reaction between (A2) and the organic acid group in (A1) is carried out in the presence or absence of a solvent. Carbon dioxide and alcohol, which are by-produced in the anion exchange reaction, are appropriately removed from the reaction system. By removing, an alkyl (meth) acrylate copolymer (A) having a quaternary ammonium / organic acid base is obtained.

In the production of (A), (A2) and (A)
The molar ratio to the organic acid group in 1) is usually (0.001 to
1): 1, preferably (0.01-1): 1, more preferably (0.05-1): 1.

The alkyl (meth) acrylate copolymer (A) having a quaternary ammonium / organic acid base in the present invention is characterized in that the organic acid group in (A1) and (A)
In addition to the method of reacting 2), for example, at least one organic acid group of the polymerizable monomer (a2) having an organic acid group is reacted with (A2) in the same manner as described above. To produce a monomer (a4) having a quaternary ammonium / organic acid base, and to copolymerize it with the above-mentioned (a1), (a2) and, if necessary, (a3) (hereinafter referred to as the production method). In some cases).

In the above (a4), when all of R ^{1 to} R ⁴ in (A2) represented by the general formula (2) are the same, the crystallinity of the obtained monomer increases, and In some cases, problems such as reduced solubility in monomers and solvents and difficulty in handling during polymerization may occur. Therefore, it is desirable that at least one of R ^{1 to} R ⁴ has a different number of carbon atoms.

In the present invention, the content of the quaternary ammonium / organic acid base represented by the general formula (1) in (A) is usually 0.1 to 30% by weight based on the weight of (A). %, Preferably 0.2 to 20% by weight, more preferably 0.5 to 10% by weight. If the amount of the quaternary ammonium / organic acid base is less than 0.1% by weight, the resulting pressure-sensitive adhesive will have insufficient antistatic properties. It no longer functions as an adhesive.

In the present invention, (A1) or (A) by the above-mentioned production method can be carried out by a known polymerization method (bulk polymerization, solution polymerization, emulsion polymerization, suspension polymerization, etc.) by a known polymerization initiator (azobisisopropane). Azo-based polymerization initiators such as butyronitrile and azobisisovaleronitrile; peroxide-based polymerization initiators such as benzoyl peroxide, di-t-butyl peroxide and lauryl peroxide; and known chain transfer agents (mercapto) Group-containing chain transfer agent).

The molecular weight of the alkyl (meth) acrylate copolymer (A) having a quaternary ammonium / organic acid base in the present invention is a weight average molecular weight (in terms of polystyrene) determined by gel permeation chromatography (GPC). Usually 10,000-1,000,000,
It is preferably from 50,000 to 1,000,000, particularly preferably from 200,000 to 1,000,000.

The pressure-sensitive adhesive of the present invention may contain a known crosslinking agent for the purpose of further improving cohesion. Examples of the crosslinking agent include melamine derivatives [hexamethylolmelamine, hexamethoxymethylmelamine, hexabutoxymethylmelamine, etc.], polyisocyanate compounds [tolylene diisocyanate, xylylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, 2,4- or 4, Blocked polyisocyanate compounds such as diisocyanate compounds such as 4-diphenylmethane diisocyanate and their multimers (biuret form, isocyanurate form, etc.), adducts of polyisocyanates to polyhydric alcohol compounds such as trimethylolpropane, etc. Of adducts of polymers or adducts of ketoxime, phenol, lactam, etc.], polyepoxy compounds Bisphenol A · epichlorohydrin condensate type of epoxy compounds, polyglycidyl ether of polyoxyalkylene polyols, glycerol di- - or triglycidyl ether, tetraglycidyl xylylenediamine, etc.] and the like.

The pressure-sensitive adhesive of the present invention may be used by blending various known additives within a range that does not impair the functions of the present invention, such as antistatic properties, non-staining properties, and adhesive properties. it can. As the additive, a tackifying resin [rosin,
Rosin derivative or its hydrogenated product, polyterpene resin, terpene phenol resin, xylene resin, styrene resin, cumarone / indene resin, C5 petroleum resin, C9
Petroleum resin, alicyclic hydrogenated petroleum resin, etc.), plasticizer [carboxylic acid ester represented by phthalic acid ester, paraffin chloride, etc.], coloring agent [titanium oxide, calcium carbonate, etc.], ultraviolet ray inhibitor [ Benzophenone UV inhibitors, etc., fungicides [cuprous oxide, phenolic compounds, etc.], defoamers [alcohols, silicone compounds, etc.]
And so on.

The pressure-sensitive adhesive of the present invention can be applied to a substrate directly or by a transfer method using a usual coating apparatus. Alternatively, only the pressure-sensitive adhesive may be used in the form of a sheet. The amount of application when applied to a substrate varies depending on the application, but is usually 1 to 500 g / m ² . Examples of the substrate that can be used include films of various plastics such as polyethylene, polypropylene, polyethylene terephthalate, and soft polyvinyl chloride, resin plates or foams, paper, metal plates or foils, and wood. When a thermally sensitive plastic film or the like is used as the substrate, coating by a transfer method is preferable. After coating and drying on the base material, curing is carried out if necessary and complete curing (especially when a cross-linking agent is used), so that sufficient adhesive properties are exhibited. Curing conditions are, for example, usually 3 to 7 days at room temperature, and 1 to 4 at 40 to 50 ° C.
Two days. Adhesive materials using the pressure-sensitive adhesive of the present invention include dicing tapes, tapes for processing electric and electronic components such as carrier tapes, stainless steel plates, surface protection tapes or sheets such as plastic plates, foot wipe mats, adhesive labels, and stickers. , Tapes and the like.

[0027]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.
In the following, “part” indicates “part by weight” and “%” indicates “% by weight”.

[Production of Quaternary Ammonium Carbonate] Production Example 1 Triethylamine (1 mol) was placed in a stirred autoclave.
Dimethyl carbonate (1 mol) and methanol (2 mol) as a solvent were charged and reacted at a reaction temperature of 110 ° C. for 12 hours, and then methanol was distilled off under reduced pressure at 50 ° C.
Methyl triethyl ammonium monomethyl carbonate (A
2-1) was obtained.

[Production of Polymerizable Monomer Having Quaternary Ammonium Carboxylate Group] Production Example 2 Triethylamine (1 mol) was added to a stirred autoclave.
Dimethyl carbonate (1 mol) and methanol (2 mol) as a solvent were charged and reacted at a reaction temperature of 110 ° C. for 12 hours to obtain a methanol solution of methyltriethylammonium / monomethyl carbonate (A2-1). This was charged with acrylic acid (1 mol), and by-produced carbon dioxide gas and methanol were removed to obtain methyltriethylammonium acrylate (a4-1).

[Production of Alkyl (meth) acrylate Copolymer Having Quaternary Ammonium / Organic Acid Base] Production Example 3 Four units equipped with a stirrer, thermometer, reflux condenser, dropping funnel, and nitrogen gas inlet tube Ethyl acetate 184
And 120 parts of cyclohexane, and the temperature was raised to 75 ° C. Then, 238 parts of n-butyl acrylate, 78 parts of 2-ethylhexyl acrylate, 16 parts of acrylic acid, 48 parts of vinyl acetate, and a monomer obtained by ring-opening addition of succinic anhydride to an adduct of polycaprolactone to 2-hydroxyethyl methacrylate [trade name] "FM-1A" manufactured by Daicel Chemical Industries, Ltd.] and 0.3 parts of 2,2'-azobisisobutyronitrile (AIBN). The monomer mixture was dropped continuously over 4 hours with a dropping funnel while nitrogen gas was passed into the Kolben to perform radical polymerization. After the completion of the dropwise addition, a solution prepared by dissolving 1.5 parts of AIBN in 80 parts of ethyl acetate was continuously added using a dropping funnel from the second hour to the fourth hour after the completion of the dropwise addition. After continuing the polymerization at the boiling point for 4 hours, 216 parts of toluene was added to obtain a solution (A1-1) of an alkyl (meth) acrylate copolymer having a carboxylic acid group in the molecular side chain. The (A1-1) obtained in Production Example 1 was added to 100 parts of (A1-1).
2-1) A solution of an alkyl (meth) acrylate copolymer having a quaternary ammonium carboxylate group (A) by adding 3.2 parts and removing by-produced carbon dioxide gas.
-1) was obtained. Viscosity of the (A-1) (B-type viscometer: 25
° C, the same applies hereinafter) of 5,800 cP and a solid content of 41.
The weight average molecular weight (in terms of polystyrene, hereinafter the same) of 9% by GPC was about 470,000.

Production Example 4 The same operation as in Production Example 3 was carried out using the following monomer composition to prepare a solution (A1-2) of an alkyl (meth) acrylate copolymer having a carboxylic acid group in the molecular side chain. did. Monomer composition: 142 parts of n-butyl acrylate 182 parts of 2-ethylhexyl acrylate 16 parts of acrylic acid 20 parts 40 parts of FM-1A 40 parts of vinyl acetate 100 parts of (A1-2) and obtained in Production Example 1 (A2 -1)
The same operation as in Production Example 3 was carried out using 2.1 parts of the solution to obtain a solution (A-2) of an alkyl (meth) acrylate copolymer having a quaternary ammonium carboxylate group. The viscosity of (A-2) was 5,000 cP, the solid content concentration was 42.1%, and the weight average molecular weight was about 450,000.

Production Example 5 The same operation as in Production Example 3 was performed using the following monomer composition to prepare a solution (A1-3) of an alkyl (meth) acrylate copolymer having a carboxylic acid group in the molecular side chain. did. Monomer composition: n-butyl acrylate 190 parts 2-ethylhexyl acrylate 190 parts acrylic acid 16 parts 2-hydroxyethyl acrylate 4 parts 100 parts of (A1-3) and obtained in Production Example 1 (A2-1)
The same operation as in Production Example 3 was carried out using 4.2 parts to obtain a solution (A-3) of an alkyl (meth) acrylate copolymer having a quaternary ammonium carboxylate group. The viscosity of (A-3) was 4,700 cP, the solid content concentration was 41.7%, and the weight average molecular weight was about 510,000.

Production Example 6 The same operation as in Production Example 3 was carried out using the following monomer composition to prepare a solution (A1-4) of an alkyl (meth) acrylate copolymer having a carboxylic acid group in the molecular side chain. did. Monomer composition: 2-ethylhexyl acrylate 324 parts Acrylic acid 16 parts Itaconic acid 12 parts Vinyl acetate 56 parts 100 parts of (A1-4) and obtained in Production Example 1 (A2-1)
The same operation as in Production Example 3 was carried out using 4.2 parts to prepare a solution (A-4) of an alkyl (meth) acrylate copolymer having a quaternary ammonium carboxylate group. The viscosity of (A-4) was 5,400 cP, the solid content concentration was 42.3%, and the weight average molecular weight was about 460,000.

Production Example 7 The same operation as in Production Example 3 was carried out using the following monomer composition to prepare a solution (A1-5) of an alkyl (meth) acrylate copolymer having a carboxylic acid group in the molecular side chain. did. Monomer composition: n-butyl acrylate 152 parts 2-ethylhexyl acrylate 184 parts Acrylic acid 16 parts Vinyl acetate 48 parts 100 parts of (A1-5) obtained in Production Example 1 (A2-1)
The same operation as in Production Example 3 was carried out using 2.4 parts of the solution to obtain a solution (A-5) of an alkyl (meth) acrylate copolymer having a quaternary ammonium carboxylate group. The viscosity of (A-5) was 4,200 cP, the solid content concentration was 42.1%, and the weight average molecular weight was about 450,000.

Production Example 8 Ethyl acetate 88 was added to a four-necked kolben equipped with a stirrer, thermometer, reflux condenser, dropping funnel and nitrogen gas inlet tube.
And 88 parts of cyclohexane, and the mixture was heated to 75 ° C.
Next, 24 parts of (a4-1) obtained in Production Example 2, 140 parts of n-butyl acrylate, 188 parts of 2-ethylhexyl acrylate, 8 parts of acrylic acid, methyl methacrylate 2
0 parts, styrene 20 parts and AIBN 0.4 part were mixed. The monomer mixture was continuously dropped by a dropping funnel over 4 hours while passing nitrogen through the kolben, to perform radical polymerization. After the completion of the dropwise addition, a solution prepared by dissolving 1.5 parts of AIBN in 88 parts of ethyl acetate was continuously added from the second hour after the completion of the dropwise addition over 4 hours using a dropping funnel. After continuing the polymerization at the boiling point for 4 hours, 336 parts of toluene was added as a diluting solvent to obtain a solution (A-6) of an alkyl (meth) acrylate copolymer having a quaternary ammonium carboxylate group. Was. The viscosity of (A-6) was 3,900 cP, the solid content concentration was 40.1%, and the weight average molecular weight was about 410,000.

Production Example 9 Toluene 2 having the following monomer composition and added as a diluent solvent:
16 parts of 184 parts of ethyl acetate and 1 part of cyclohexane
The same operation as in Production Example 3 was carried out except that 20 parts of the mixture were heated in advance in a four-necked kolben, and a solution of an alkyl (meth) acrylate copolymer having a phosphate group in a molecular side chain (A1 -7) was prepared. Monomer composition: n-butyl acrylate 166 parts 2-ethylhexyl acrylate 166 parts vinyl acetate 48 parts 2-methacryloyloxyethyl acid phosphate 20 parts [trade name "JPA-514": manufactured by Johoku Chemical Co., Ltd.] A1-7) 100 parts and obtained in Production Example 1 (A2-1)
The same operation as in Production Example 3 was carried out using 1.1 parts of the solution to obtain a solution (A-7) of an alkyl (meth) acrylate copolymer having a quaternary ammonium phosphate group.
(A-7) has a viscosity of 1,000 cP and a solid content of 4
2.4%, weight average molecular weight was about 100,000.

Production Example 10 The same operation as in Production Example 3 was carried out except that 120 parts of methanol was used instead of 120 parts of cyclohexane in the following monomer composition, and an alkyl having a sulfonic acid group in a molecular side chain was obtained. Solution of meth) acrylate-based copolymer (A1-
8) was prepared. Monomer composition: n-butyl acrylate 166 parts 2-ethylhexyl acrylate 166 parts vinyl acetate 48 parts 2-acrylamide-2-methylpropanesulfonic acid 20 parts [trade name "TBAS-Q": manufactured by Nitto Chemical Co., Ltd.] 100 parts of (A1-8) and (A2-1) obtained in Production Example 1.
Using 1.5 parts and the same operation as in Production Example 3, a solution (A-8) of an alkyl (meth) acrylate copolymer having a quaternary ammonium sulfonate group was obtained. The viscosity of (A-8) was 6,900 cP, the solid concentration was 41.8%, and the weight average molecular weight was about 400,000.

Production Example 11 N, N-di (2-hydroxyethyl)
Charge 185 parts of sulfamic acid and 593 parts of toluene,
At a reaction temperature of 30 ° C., 222 parts of methacryloyl isocyanate [trade name “MAI”: manufactured by Nippon Paint Co., Ltd.] was added dropwise over 1 hour, and the mixture was further reacted for 1 hour.
The toluene was distilled off at 50 ° C. under reduced pressure to obtain an adduct (B-1) of methacryloyl isocyanate and N, N-di (2-hydroxyethyl) sulfamic acid. Using this, cyclohexane 12 with the following monomer composition
Same as Production Example 3 except that 120 parts of methanol was used instead of 0 parts, and 216 parts of toluene to be added as a diluting solvent was previously charged in a four-necked kolben together with 184 parts of ethyl acetate and 120 parts of methanol and heated. To obtain a solution of an alkyl (meth) acrylate copolymer having a sulfamic acid group in the molecular side chain (A1-9)
It was created. Composition of monomer: 166 parts of n-butyl acrylate 166 parts of 2-ethylhexyl acrylate 48 parts of vinyl acetate (B-1) 20 parts 100 parts of (A1-9) and (A2-1) obtained in Production Example 1
The same operation as in Production Example 3 was carried out using 0.8 part of the solution to obtain a solution (A-9) of an alkyl (meth) acrylate copolymer having a quaternary ammonium sulfamate group. The viscosity of (A-9) was 2,900 cP, the solid content concentration was 41.3%, and the weight average molecular weight was about 150,000.

Comparative Production Example 1 The same operation as in Production Example 3 was carried out with the following monomer composition, and a solution of a comparative alkyl (meth) acrylate copolymer (S
-1) was created. Monomer composition: n-butyl acrylate 238 parts 2-ethylhexyl acrylate 150 parts acrylic acid 12 parts The viscosity of (S-1) is 2,900 cP, and the solid content concentration is 4
0.3%, weight average molecular weight was about 410,000. To 250 parts of this (S-1) was added 1.5 parts of lithium perchlorate and polyether diol [trade name "Sannicks PP-4".
00 ": manufactured by Sanyo Chemical Industries, Ltd.] to obtain 30 parts of a comparative antistatic pressure-sensitive adhesive solution (Y-1).

Comparative Production Example 2 The same operation as in Production Example 3 was carried out with the following monomer composition, and a solution of a comparative alkyl (meth) acrylate copolymer (S
-2) was prepared. Monomer composition: butyl acrylate 260 parts 2-ethylhexyl acrylate 128 parts acrylic acid 12 parts The viscosity of (S-2) is 4,100 cP, and the solid concentration is 4.
0.4%, weight average molecular weight was about 460,000. The (S
-2) 7.5 parts of lithium perchlorate and 750 parts of polyether triol [trade name "SANNIX GP-400"
0 ": manufactured by Sanyo Chemical Industries, Ltd.], to obtain a comparative antistatic pressure-sensitive adhesive solution (Y-2).

Comparative Production Example 3 The same operation as in Production Example 3 was carried out with the following monomer composition, and a solution of a comparative alkyl (meth) acrylate copolymer (S
-3) was prepared. Monomer composition: butyl acrylate 40 parts 2-ethylhexyl acrylate 320 parts 2-hydroxyethyl acrylate 20 parts acrylic acid 20 parts The viscosity of (S-3) is 2,100 cP, and the solid content concentration is 4
0.3%, weight average molecular weight was about 400,000. Anionic surfactant [Chemistat 3033: manufactured by Sanyo Chemical Industries, Ltd.] is added to 750 parts of (S-3).
Was mixed with 10 parts of glycerin to obtain a comparative antistatic pressure-sensitive adhesive solution (Y-3).

Example 1 N, N, N ', N'-tetraglycidylxylylenediamine [manufactured by Mitsubishi Gas Chemical Industry Co., Ltd.] was added to 100 parts of (A-1) prepared in Production Example 3 as a crosslinking agent. Name: "TET
RAD-X "], and mixed uniformly to prepare a mixed solution. This mixed solution was applied to a silicone release paper so that the dry film thickness became 100 μm, dried at 100 ° C. for 5 minutes, and cured at 50 ° C. for 48 hours to prepare a pressure-sensitive adhesive sheet. This pressure-sensitive adhesive sheet was cut into a predetermined area to form a test piece, which was used to evaluate the antistatic property by the following performance test method. Further, the above-mentioned mixture was applied to a polyethylene terephthalate film so that the dry film thickness became 25 μm, and 100 ° C. ×
The coating film was dried under the condition of 2 minutes and cured at 50 ° C. for 48 hours to prepare a coated film. The coated film was cut into a predetermined width to obtain a test piece, and the test piece was used to evaluate the eluate when boiled in water, the contamination to the adherend surface, and the holding power using the test piece described below. . Table 1 shows the results of these evaluations.

Examples 2 to 9 The same operation as in Example 1 was performed using each of (A-2) to (A-9) prepared in Production Examples 4 to 11, and test pieces were prepared. Was evaluated. Table 1 shows the evaluation results.

Comparative Examples 1 to 3 Using (Y-1) to (Y-3) prepared in Comparative Production Examples 1 to 3, the same operation as in Example 1 was carried out to prepare test specimens and perform each of the tests. Was evaluated. Table 1 shows the evaluation results.

[Performance Test Method] Measurement of surface resistivity and volume resistivity (antistatic property): 2
After leaving the test piece under the condition of 3 ° C. × 65% RH for 12 hours, the volume resistivity and the surface resistivity were measured by the method described in JIS-K6911. Dissolution test (dissolution test of alkali metal and halogen ion): 20 m in 100 ml Erlenmeyer flask
1 l of ultrapure water was added, 1 g of a test piece was immersed, left in an autoclave at 121 ° C for 24 hours, concentrated to 1/10, and the concentration of metal ions was measured with an atomic absorption spectrophotometer. The halogen ion was measured by a colorimetric method. Stain on the adherend surface: stainless steel plate (SUS304B
A) A test piece having an area of 50 × 100 mm was attached to A),
After leaving for 1 week under the condition of 0 ° C. × 90% RH, the test piece was peeled off, and the presence or absence of contamination such as clouding and adhesive residue on the surface of the stainless steel plate was visually judged according to the following criteria. ○: no fogging or adhesive residue on the stainless steel plate surface △: slight fogging or adhesive residue on the stainless steel plate surface ×: significant fogging or adhesive residue on the stainless steel plate surface Holding force (cohesive force): stainless steel plate (SUS304BA) )
A test piece was stuck so that the stuck area would be 25 mm x 25 mm, and it was pressed back and forth with a 5 kg roller once.
After leaving for 1 hour under the conditions of ° C and 65% RH, a load of 1 kg was applied in an atmosphere of 40 ° C, and the displacement distance (unit: mm) after 24 hours was measured.

[0046]

[Table 1]

[0047]

The antistatic pressure-sensitive adhesive of the present invention has the following effects. (1) Since it is mainly composed of an alkyl (meth) acrylate copolymer having a quaternary ammonium / organic acid group in the molecular side chain, it exhibits excellent antistatic properties. (2) Since it does not contain low molecular weight compounds such as surfactants and polyether polyols, there is no bleed-out of low molecular weight components derived from them and there is no surface contamination of adherends such as stainless steel plates and plastic plates. . (3) Since compounds containing alkali metals and halogens are not used, there is no elution or bleeding of metal ions and halogen ions derived from them, and they can be attached to adherends such as silicon wafers that dislike these ions. Can be used. Because of the above effects, the pressure-sensitive adhesive product using the antistatic pressure-sensitive adhesive of the present invention is particularly suitable for dicing tape, tape for processing electronic components such as carrier tape, stainless steel,
It can be suitably used for surface protection tapes such as plastics, mats for wiping feet, and the like.

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Continuation of front page (72) Inventor Toshiro Shimada 11-11, Hitotsubashi-Honcho, Higashiyama-ku, Kyoto City Examiner at Sanyo Chemical Industries Co., Ltd. Tatsuya Ando (56) References JP-A-2-238076 (JP, A) JP JP-A-5-161618 (JP, A) JP-A-56-36939 (JP, A) JP-A-9-95471 (JP, A) JP-A-62-321 (JP, A) JP-A-55-81635 (JP) JP-A-5-154119 (JP, A) JP-A-7-252456 (JP, A) JP-A-9-137149 (JP, A) JP-A-8-155040 (JP, A) 62-292140 (JP, A) JP-A-60-147330 (JP, A) JP-A-9-157623 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C09J 1/00 -201/10 CA (STN) REGISTRY (STN)

Claims (4)

(57) [Claims] [Claim 1] At least one of the following general formulas (1) in a side chain of a molecule: [Wherein, R ^{1 to} R ³ are linear or branched, saturated or unsaturated hydrocarbon groups having 1 to 11 carbon atoms (provided that R ^{1 to} R ³
Any two of the above may be bonded via O or N as necessary to form a heterocyclic ring. ) And R
⁴ represents an alkyl group having 1 to 8 carbon atoms or an aromatic hydrocarbon group, and X represents an acid group selected from a carboxylic acid group, a sulfonic acid group, a sulfamic acid group and a (phosphite) phosphate group. And a quaternary ammonium / organic acid base-containing alkyl (meth) acrylate-based copolymer (A) represented by the formula (A), wherein the alkyl (meth) acrylate-based copolymer having an organic acid group constituting (A) ( A1) is an alkyl (meth) acrylate having 4 to 12 carbon atoms (a
1) comprising a polymerizable monomer (a2) having an organic acid group and, if necessary, another polymerizable monomer (a3);
(A2) a pressure-sensitive adhesive tape or sheet obtained by applying and drying an antistatic pressure-sensitive adhesive comprising any of the following: A polymerizable monomer having a carboxylic acid group selected from the following; monoalkyl esters of dibasic acids (the dibasic acids are selected from maleic acid, itaconic acid and fumaric acid);
(Meth) acryloylpropionic acid, 2-hydroxyalkyl (hydroxyalkyl group having 2 to 3 carbon atoms) succinic anhydride ring-opened adduct to (meth) acrylate, polyoxyalkylene (alkylene group having 2 to 4 carbon atoms) glycol Ring-opening addition of succinic anhydride to a ring-opening adduct of succinic anhydride to mono (meth) acrylate and a polyadduct of caprolactone to 2-hydroxyalkyl (2 to 3 carbon atoms of hydroxyalkyl group) (meth) acrylate. Compound (sub) polymerizable monomer having a phosphoric acid ester group, polymerizable monomer having a sulfonic acid group, polymerizable monomer having a sulfamic acid group, and a mixture of two or more of these. (A1) constituting (A1): (a
2): The weight ratio of (a3) is (30-99.8) :( 0.
2-30): The pressure-sensitive adhesive tape or sheet according to claim 1, wherein (0-40). 3. The content of the quaternary ammonium / organic acid base represented by the general formula (1) in (A) is 0.1 to 30% by weight based on the weight of (A). Item 3. The pressure-sensitive adhesive tape or sheet according to item 1 or 2. 4. The pressure-sensitive adhesive tape or sheet according to claim 1, which is a dicing tape, a carrier tape, or a protective sheet made of a steel plate or a plastic plate.