JPH09104845A - Hot melt-type tacky agent composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a hot melt-type tacky agent composition excellent in mechanical properties. SOLUTION: This hot melt-type tacky agent composition consists of a polymer obtained by polymerizing a mixture consisting of 85.0-99.0mol.% of (A) a vinyl monomer essentially containing a monomer having a carboxyl group, which has a glass transition temperature of -100 to -40 deg.C when it is polymerized, and 1.0-15.0mol.% of (B) a polyvalent metal compound consisting of one or more than one kind selected from an oxide, a hydroxide and an organic carboxylic acid salt and essentially containing and an oxide and/or hydroxide. In the mixture, the polyvalent metal compound (B) is dissolved in the vinyl monomer (A).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an acrylic hot-melt pressure-sensitive adhesive composition having excellent heat resistance. More specifically, the present invention relates to an acrylic hot-melt pressure-sensitive adhesive composition having excellent heat resistance, cohesive strength, adhesive strength, tackiness, and other adhesive characteristics, and excellent viscosity characteristics upon heating and melting.

[0002]

2. Description of the Related Art Acrylic adhesive compositions have excellent adhesive properties such as adhesive strength, cohesive strength, tackiness, and light resistance, weather resistance, oil resistance, transparency, etc., and are widely used in adhesive tapes, labels, sheets, etc. Has been done.

As a conventional acrylic pressure-sensitive adhesive composition,
As a component having (meth) acrylic acid alkyl ester capable of forming a polymer having a relatively low glass transition point and having an adhesive property such as n-butyl acrylate and 2-ethylhexyl acrylate as a main component, and improving cohesive force A polymer obtained by copolymerizing a polymerizable mixture containing a vinyl compound having a functional group such as acrylic acid or hydroxyethyl acrylate or a vinyl compound capable of forming a polymer having a relatively high glass transition point such as methyl methacrylate or vinyl acetate. Is used.

The above-mentioned acrylic pressure-sensitive adhesive composition is usually
It is of the solvent or emulsion type and these are already commercially available. However, since the solvent-type pressure-sensitive adhesive composition contains a large amount of organic solvent, there are problems such as environmental pollution, fire, and the risk of explosion, and the emulsion-type pressure-sensitive adhesive composition is difficult to dry. There are problems such as reduced efficiency. In order to solve these problems, it has been long awaited to make the acrylic pressure-sensitive adhesive composition solvent-free.

As a method for overcoming the above problems, an attempt to utilize a metal bridge has been proposed. For example, a method of adding o-methoxyaryl acid to a zinc ion cross-linking system of a carboxylic acid group-containing polymer (Japanese Examined Patent Publication No. 5-68519) or an acrylic ester vinyl monomer and a metal salt of (meth) acrylic acid are used together. Polymerization method (Japanese Patent Laid-Open No. 5-202345)
No.) or an alkyl ester of (meth) acrylic acid, a metal salt of a polymerizable unsaturated carboxylic acid, and a monomer mixture consisting of another comonomer, which is radically polymerized in bulk (Japanese Patent Application Laid-Open No. 5-312058).
6-74110) and the like.

However, in the method of Japanese Patent Publication No. 5-68519, the zinc compound is added later to the acid-containing polymer (ie, the zinc compound is not polymerized in the coexistence but is added to the polymer after polymerization). There is a problem in that the formation of zinc crosslinks is incomplete and the heat resistance of the pressure-sensitive adhesive composition cannot be obtained.

Further, according to the method of JP-A-5-202345, the solubility of the zinc salt in the vinyl monomer of (meth) acrylic acid ester is low, so that when a compound acting as a solubilizer does not exist. Has a problem that the amount of zinc salt that can be introduced into the pressure-sensitive adhesive composition is limited to a small amount, and the heat resistance and cohesive force of the pressure-sensitive adhesive composition cannot be obtained. Further, Japanese Patent Application Laid-Open
In the method of No. 202345, when a vinyl monomer having an amide group coexists in the polymerization system, the solubility of the zinc salt in the (meth) acrylic acid ester vinyl monomer is improved, so that the pressure-sensitive adhesive composition It is possible to increase the amount of zinc salt to be introduced. However, the pressure-sensitive adhesive composition thus obtained has a problem that it does not melt even if it is heated and remains gelled.

Further, in the method of JP-A-56-74110, when the polymer is intended for thermoplastic processing, the amount of metal acrylic acid or metal methacrylate is 1 mol based on the total molar amount of the monomers used. However, the balance between heat resistance and molding processability was insufficient.

Therefore, various studies have been conducted as described above for making the acrylic hot-melt type pressure-sensitive adhesive composition solvent-free. To date, the viscosity characteristics at the time of heating and melting and the cohesive force at room temperature or high temperature are compatible with each other. At present, it is very difficult to obtain such a hot-melt type pressure-sensitive adhesive composition.

[0010]

DISCLOSURE OF THE INVENTION The present invention solves the above problems that conventional acrylic pressure-sensitive adhesive compositions have. Therefore, the object of the present invention is to have a high metal salt content, excellent heat resistance and cohesive strength, adhesive properties such as adhesive strength and tack, excellent viscosity characteristics upon heating and melting, and a label, adhesive tape or sheet. Another object of the present invention is to provide a solvent-free acrylic hot melt type pressure-sensitive adhesive composition for use in the like.

[0011]

Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that as a new attempt to utilize metal cross-linking, a conventional acrylic ester vinyl monomer is used. The polymer formed by the polymerization of the monomer mixture which is directly added in the form of a metal salt of a polymerizable unsaturated carboxylic acid to a hot-melt pressure-sensitive adhesive composition, rather than a polymerizable unsaturated carboxylic acid A polymer formed by polymerizing a mixture obtained by dissolving a polyvalent metal compound consisting of an oxide and / or hydroxide (essential component) and an organic carboxylic acid salt (optional component) in the vinyl monomer contained. By using a hot-melt pressure-sensitive adhesive composition,
It has been found that the above problems can be solved.

That is, in a mixture prepared by dissolving a polyvalent metal compound such as an oxide in a vinyl monomer having a polymerizable unsaturated carboxylic acid, the polymerizable unsaturated carboxylic acid and the polyvalent metal in the vinyl monomer are mixed with each other. Formed by polymerization of this mixture because the polymerizable unsaturated carboxylic acid polyvalent metal salt is produced in the form of a polyvalent metal salt soluble in the total monomer solution by the oxide / hydroxide in the metal compound. The polymer can contain a polyvalent metal salt in a high concentration. Therefore, it has been found that a hot-melt pressure-sensitive adhesive composition made of this polymer can have excellent heat resistance and cohesive strength, adhesive characteristics such as adhesive strength and tack, and excellent viscosity characteristics upon heating and melting, The present invention has been completed.

Further, the above problems can also be solved by using a hot-melt pressure-sensitive adhesive composition composed of a polymer formed by polymerizing a mixture containing an organic carboxylic acid having no polymerizable double bond. Found.

In this case, due to the coexistence of the organic carboxylic acid having no polymerizable double bond, an organic carboxylic acid having no polymerizable double bond is partially present in the above-mentioned polymerizable unsaturated carboxylic acid polyvalent metal salt. Since the polyvalent metal salt in the bound form is produced in the form of the polyvalent metal salt which is soluble in the total monomer solution, the polymer formed by the polymerization of this mixture contains the polyvalent metal salt in a high concentration. At the same time, when the cross-linking between the linear polymers by the polyvalent metal salt occurs, the cross-linking is not caused by the organic carboxylic acid partially having no polymerizable double bond. Therefore, in the hot-melt type pressure-sensitive adhesive composition made of this polymer, the moldability can be expressed while maintaining the above characteristics when the thermoplastic processing is intended, so that the balance between the heat resistance and the moldability is sufficient. The present invention has been discovered and has led to the completion of the present invention.

That is, the object of the present invention is (1) a vinyl monomer (A) which essentially contains a monomer having a carboxyl group and has a glass transition temperature of the polymer in the range of -100 to -40 ° C. A polyvalent metal compound (B) containing 85.0 to 99.0 mol% and essentially containing an oxide and / or a hydroxide and at least one selected from an oxide, a hydroxide and an organic carboxylate (B ) 1.0 to 15.0 mol% and a polymer formed by polymerizing a mixture of the polyvalent metal compound (B) dissolved in the vinyl monomer (A). This is achieved by a melt-type pressure-sensitive adhesive composition.

Another object of the present invention is (2) wherein the above mixture is a polymerizable double bond based on 100 mol% of the total amount of the vinyl monomer (A) and the polyvalent metal compound (B). The hot-melt pressure-sensitive adhesive composition according to (1) above, which further contains 0.1 to 10 mol% of an organic carboxylic acid (C) having no

Still another object of the present invention is: (3) The above-mentioned vinyl monomer (A) is mainly composed of butyl acrylate and / or 2-ethylhexyl acrylate. It is also achieved by the hot-melt pressure-sensitive adhesive composition shown in (2).

Still another object of the present invention is (4)
The mixture contains 0.1 to 100 parts by weight of water of the vinyl monomer (A) and the polyvalent metal compound (B) in a total amount of 100 mol%.
The above (1) to (3) further containing 3.0 mol%
It is also achieved by the hot-melt type pressure-sensitive adhesive composition shown in any one of the above.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION The constitution of the present invention for achieving the above object will be described in detail below.

First, the polyvalent metal compound (B) according to the present invention
In a vinyl monomer (A) (hereinafter, also simply referred to as a mixture, when the mixture contains an organic carboxylic acid (C) having no polymerizable double bond described later) The ratio of the vinyl monomer (A) in the mixture is the organic carboxylic acid (C) is usually 85.0 to 99.0 mol%, preferably 90.0 to 9
It is preferably 7.0 mol%. Moreover, the ratio of the polyvalent metal compound (B) in the mixture is usually 1.0 to 15.0.
It is preferable that the amount is mol%, preferably 3.0 to 10.0 mol%.

Vinyl monomer (A) in the above mixture
Is less than 85.0 mol% or the proportion of the polyvalent metal compound (B) exceeds 15.0 mol%, the polyvalent metal compound (B) becomes the vinyl monomer (A). It may not completely dissolve, precipitation may occur during polymerization, and a uniform hot-melt pressure-sensitive adhesive composition may not be obtained, and the original properties of the obtained hot-melt pressure-sensitive adhesive composition may not be maintained. . When the proportion of the vinyl monomer (A) exceeds 99.0 mol% or the proportion of the polyvalent metal compound (B) is less than 1.0 mol%, the vinyl monomer (A) is The content ratio of the polymerizable unsaturated carboxylic acid polyvalent metal salt soluble in the total monomer solution formed in the mixture by the monomer having a carboxyl group and the polyvalent metal compound (B) becomes relatively small, and The heat resistance of the melt-type pressure-sensitive adhesive composition may be insufficient, and in a hot-melt pressure-sensitive adhesive composition intended for thermoplastic processing, the balance between moldability and heat resistance may not be sufficient.

As the vinyl monomer (A) used in the present invention, for example, methyl (meth) acrylate, (meth)
Ethyl acrylate, n-propyl (meth) acrylate,
Isopropyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, (meth)
Sec-butyl acrylate, pentyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, dodecyl (meth) acrylate, octadecyl (meth) acrylate and Aliphatic ester compounds of (meth) acrylic acid such as 2-hydroxyethyl (meth) acrylate, benzyl (meth) acrylate, aromatic ester compounds of (meth) acrylic acid such as phenyl (meth) acrylate, ethylene, Olefinic hydrocarbons such as propylene and vinyl chloride or halogen-substituted products thereof, aromatic vinyl compounds such as styrene and methylstyrene, vinyl ester compounds of monovalent carboxylic acids such as vinyl acetate and vinyl propionate, (meth) Allyl alcohol, Croton alcohol Which unsaturated alcohol compounds, such as (meth) acrylic acid, crotonic acid, cinnamic acid alpha, beta-
Of ethylenically unsaturated carboxylic acid compounds, unsaturated dibasic carboxylic acids such as maleic acid, fumaric acid and itaconic acid, monohydric alcohols such as maleic acid monomethyl ester and maleic acid monoallyl ester, and unsaturated dibasic carboxylic acids Polyvinyl compounds such as monoester compounds, divinylbenzene, ethylene glycol diacrylate, ethylene glycol dimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate and diallyl maleate, 2 (N, N-
Amine compounds such as dimethylamino) ethyl acrylate, 2 (N, N-dimethylamino) ethyl methacrylate, 2 (N, N-diethylamino) ethyl acrylate, 2 (N, N-diethylamino) ethyl methacrylate, 2-vinylpyridine, 3 -Vinylpyridine, 4-vinylpyridine, 2-methyl-5-vinylpyridine, 2-
Ethyl-5-vinylpyridine, 2-vinyl-5-ethylpyridine, 2-vinylquinoline, 1-vinylcarbazole, 3-vinylcarbazole, 1-methyl-3-vinylcarbazole, 1-vinylimidazole, 2-vinylimidazole, 4-vinylimidazole, 4-vinylpyrimidine, 1-methacryloylaziridine, 2- (1-aziridinyl) ethyl methacrylate, 4-acryloyloxy-2,2,6,6-tetramethylpiperidine, 4
-Methacryloyloxy-2,2,6,6-tetramethylpiperidine, 4-acryloyloxy-1,2,2
6,6-Pentamethylpiperidine, 4-methacryloyloxy-1,2,2,6,6-pentamethylpiperidine, 9-aza-3-acryloyloxymethyl-3-ethyl-8,8,10,10-tetra Examples thereof include nitrogen atom-containing organic heterocyclic compounds such as methyl-1,5-dioxa-spiro [5.5] undecane, and among these, one kind or two or more kinds can be used.

Vinyl monomer (A) used in the present invention
Is n-butyl acrylate and / or acrylic acid 2
-Ethylhexyl as a main component (usually 50 mol% or more), preferably 80 mol% or more, it is preferable to use n-butyl acrylate or 2-ethylhexyl acrylate alone or in combination of both. You can also There is no particular limitation on the mixing ratio when the two are mixed and used. If the total amount of n-butyl acrylate and 2-ethylhexyl acrylate is less than 80 mol%, the adhesive properties of the hot melt adhesive composition may be insufficient.

Further, the vinyl monomer (A) must essentially contain a monomer having a carboxyl group. This is because the polyvalent metal compound (B) is dissolved in the vinyl monomer (A) containing the monomer having the carboxyl group to obtain the monomer having the carboxyl group and the polyvalent metal compound (B). Between the polyvalent metal oxide and / or the polyvalent metal hydroxide (hereinafter also simply referred to as polyvalent metal (hydr) oxide) in the polymerizable unsaturated carboxylic acid polyvalent soluble in all monomer solutions. Vinyl salt (A) directly in the form of polyvalent metal salt
This is because it can be formed at a ratio higher than the solubility when it is added to. Examples of the monomer having a carboxyl group include an α, β-ethylenically unsaturated carboxylic acid compound, an unsaturated dibasic carboxylic acid, a monoester compound of a monohydric alcohol and an unsaturated dibasic carboxylic acid as exemplified above. In addition to, 2-acryloyloxyethyl succinic acid,
2-methacryloyloxyethyl succinic acid, 2-acryloyloxypropyl succinic acid, 2-methacryloyloxypropyl succinic acid, 3-acryloyloxypropyl succinic acid, 3-methacryloyloxypropyl succinic acid, 2- (2-butenoyl) oxyethyl succinic acid Acid, 2
-Acryloyloxyethyl phthalic acid, 2-methacryloyloxyethyl phthalic acid, 2-acryloyloxypropyl phthalic acid, 2-methacryloyloxypropyl phthalic acid and acids having ester groups such as 3-acryloyloxypropyl phthalic acid.

The proportion of the monomer having a carboxyl group should be at least 1 equivalent to 1 equivalent of the polyvalent metal (hydroxide) in the polyvalent metal compound (B). Furthermore, since it is preferable that the production efficiency of the polymerizable unsaturated carboxylic acid polyvalent metal salt produced from the monomer having a carboxyl group and the polyvalent metal (hydroxide) is higher, the polyvalent metal ( Water) 1.0 to 1 equivalent of oxide
It is more preferable to use a monomer having 2.0 equivalents of a carboxyl group.

In addition, it is preferable to use a monomer having two or more kinds of carboxyl groups because the solubility of the polymerizable unsaturated carboxylic acid polyvalent metal salt is improved.
Thereby, for example, a polymerizable unsaturated organic carboxylic acid polyvalent metal salt can be formed between a monomer having two kinds of carboxyl groups of acrylic acid and methacrylic acid and a polyvalent metal (hydroxide) (here In the present specification, the polyvalent metal salt of an organic carboxylic acid formed between a plurality of different monomers and a polyvalent metal (hydroxide) is also referred to as an asymmetric metal salt.
The above asymmetric metal salt has an action of inhibiting aggregation of the polyvalent metal salt in the mixture and an action of promoting improvement of the dissolution stability. Therefore, uniform polymerization can be performed without forming an insoluble matter in the mixture, which is suitable for a transparent hot-melt type pressure-sensitive adhesive composition.

Next, in the present invention, the above mixture is
It may further contain 0.1 to 3.0 mol% of water based on 100 mol% of the total amount of the vinyl monomer (A) and the polyvalent metal compound (B). The water content is 0.
When it is less than 1 mol%, the effect of containing water, that is, the introduction of the polyvalent metal salt in the hot-melt pressure-sensitive adhesive composition can be made higher than in the case where water is not added In some cases, the function cannot be obtained, and as a result, the performance of the hot-melt pressure-sensitive adhesive composition such as heat resistance derived from the polyvalent metal cannot be further improved. Further, if the water content exceeds 3.0 mol%, insoluble matter may be precipitated in the mixture and a uniform polymer may not be obtained, resulting in deterioration of performance of the hot-melt pressure-sensitive adhesive composition. May be invited. The method of adding the water is not particularly limited, and a method of adding a predetermined amount of water to the polymerization system before the polyvalent metal compound (B) is dissolved in the vinyl monomer (A), and a method of previously adding vinyl monomer Although any method of adding a predetermined amount of water to the mixture after the polyvalent metal compound (B) is dissolved in the monomer (A) may be used, the polyvalent metal compound (B) may be added to the vinyl monomer (A). Is preferably added before being dissolved.

The glass transition temperature of the polymer obtained from the vinyl monomer (A) is usually from -100 ° C to -4.
It is in the range of 0 ° C, preferably -90 ° C to -40 ° C. When the glass transition temperature of the polymer obtained from the vinyl monomer (A) is less than -100 ° C, the adhesive property may be impaired, and when it exceeds -40 ° C, the viscosity property upon heating may be impaired. Sometimes. Here, when the vinyl monomer (A) is a mixture of n components (n is an integer of 2 or more) or more (component 1 to component n), the glass transition of the polymer obtained from the vinyl monomer (A) The temperature is the Fox shown below.
(1) 1 / Tg = W ₁ / Tg ₁ + W ₂ / Tg ₂ + ... + W _n / Tg _n (1) (wherein Tg is a polymer obtained from a mixture of vinyl monomers (A)) Tg ₁ is the glass transition temperature of the homopolymer of component 1 of the vinyl monomer (A), Tg _1.
2 Glass transition temperature, Tg _n of the homopolymer of component 2 of a vinyl monomer (A) is a glass transition temperature of the homopolymer of component n of the vinyl monomer (A). W ₁ is the weight fraction of component 1 of vinyl monomer (A), W ₂ is the weight fraction of component ₂ of vinyl monomer (A), W _n is the component of vinyl monomer (A) The weight fraction of n is shown. ) Is defined as the value calculated from.

Polyvalent metal compound (B) used in the present invention
In addition to the polyvalent metal oxide and / or polyvalent metal hydroxide which are essential components, an organic carboxylic acid polyvalent metal salt which is an optional component can be used. Among these, the polyvalent metal oxide and / or the polyvalent metal hydroxide, which is an essential component,
Any vinyl monomer (A) may be used as long as it can react with a monomer having a carboxyl group which is an essential component in the vinyl monomer (A) to form a polyvalent metal salt soluble in the entire monomer solution. It can be mixed and used in a ratio.

The proportion of the polyvalent metal oxide and / or the polyvalent metal hydroxide which is an essential component in the whole polyvalent metal compound (B) is usually 50 mol% or more, preferably 7%.
0 mol% or more. When the amount of the essential component is less than 50 mol%, a polymerizable unsaturated carboxylic acid polyvalent metal salt soluble in the intended total monomer solution between the essential component and the above-mentioned monomer having a carboxyl group. Is not sufficient and is not preferable.

As the organic carboxylic acid polyvalent metal salt which is an optional component, for example, acrylic acid polyvalent metal salt, methacrylic acid polyvalent metal salt, undecenoic acid polyvalent metal salt,
Oleic acid polyvalent metal salt, crotonic acid polyvalent metal salt, cinnamic acid polyvalent metal salt, isovaleric acid polyvalent metal salt, 2-acryloyloxyethyl succinic acid polyvalent metal salt, 2-acryloyloxy In addition to a polyvalent metal salt of ethylphthalic acid, a polyvalent metal salt of an organic carboxylic acid formed between a polyvalent metal compound and two organic carboxylic acids of acrylic acid and methacrylic acid (the following formula (1 2) of a polyvalent metal compound and acrylic acid and isovaleric acid
Organic carboxylic acid polyvalent metal salt formed between a polyvalent metal compound and a plurality of different organic carboxylic acids, such as an organic carboxylic acid polyvalent metal salt formed between different organic carboxylic acids In the specification, the salt is also included in the asymmetric metal salt) and the like.

[0032]

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As exemplified above, the organic carboxylic acid polyvalent metal salt may be an organic carboxylic acid polyvalent metal salt composed of one kind of organic carboxylic acid, or an organic carboxylic acid composed of a plurality of organic carboxylic acids. Although it may be a polyvalent metal salt,
For the purpose of improving the solubility of the organic carboxylic acid polyvalent metal salt, it is preferable to use an organic carboxylic acid polyvalent metal salt formed between a plurality of organic carboxylic acids and a polyvalent metal compound. In the case of an organic carboxylic acid polyvalent metal salt composed of a plurality of such organic carboxylic acids, it is more preferable to include at least one organic carboxylic acid having a polymerizable double bond. Zinc diacrylate, zinc dimethacrylate, zinc di (2-methacryloyloxyethyl phthalate), zinc di (2-methacryloyloxyethyl succinate), and the like, which have particularly excellent properties among polyvalent metal species. Is highly soluble and is preferably used. Further, in the case of an organic carboxylic acid polyvalent metal salt composed of a plurality of organic carboxylic acids, when using a saturated carboxylic acid and an unsaturated carboxylic acid as a plurality of different acids, the ratio of the two is not particularly limited, In order to impart suitable adhesive properties to the hot-melt pressure-sensitive adhesive composition, the value calculated by (moles of unsaturated organic carboxylic acid) / (total mols of organic carboxylic acid) is k value, k value is 0.1 <k <0.9, more preferably 0.1 <k <
It is preferably 0.5. If the k value is less than this range, the adhesive properties of the resulting hot melt adhesive composition may be impaired, and if the k value exceeds this range, the hot melt adhesive composition obtained. In some cases, the viscosity characteristics during heating and melting may be impaired.

The organic carboxylic acid constituting the above-mentioned polyvalent metal salt of organic carboxylic acid is not limited to the above-mentioned ones, and for example, formic acid, acetic acid, propionic acid,
Saturated aliphatic monocarboxylic acids such as isovaleric acid and hexanoic acid, saturated aliphatic dicarboxylic acids such as oxalic acid, malonic acid and succinic acid, acrylic acid, methacrylic acid, undecenoic acid, oleic acid, crotonic acid, cinnamic acid, 5 -Hexenoic acid, 3-methyl-3-butenoic acid, 3-pentenoic acid, 4
-Pentenoic acid, 4-methyl-4-pentenoic acid, 3-methyl-4-pentenoic acid, 2-acryloyl acetic acid, 3-acryloyl propionic acid, 2-methacryloyl acetic acid, 3-
Oxo-5-methyl-5-hexenoic acid, 3-oxo-4
-Methyl-4-hexenoic acid, 3-acryloylbutanoic acid, 2-acryloylaminoacetic acid, 3-acryloylaminopropionic acid, 2-methacryloylaminoacetic acid, 2
-Methacryloylaminopropionic acid, 2- (2-butenoyl) aminoacetic acid, 2-acryloylthioacetic acid, 3-
Acryloylthiopropionic acid, 2-methacryloylthioacetic acid, 2-methacryloylthiopropionic acid, 2-
(2-butenoyl) thioacetic acid, 2-acryloyloxyacetic acid, 3-acryloyloxypropionic acid, 2-methacryloyloxyacetic acid, 3-methacryloyloxypropionic acid, 4-methacryloyloxycyclohexanecarboxylic acid, 4-methacryloyloxybenzoic acid, 2 −
An acid having a polymerizable double bond such as (2-butenoyl) oxyacetic acid, 1,15-dicarboxy-4,9,12-trioxa-3,8,13-trioxo-6-pentadecene, 2-acryloyloxyethyl Succinic acid, 2-methacryloyloxyethyl succinic acid, 2-acryloyloxypropyl succinic acid, 2-methacryloyloxypropyl succinic acid, 3-acryloyloxypropyl succinic acid, 3-methacryloyloxypropyl succinic acid, 2-
(2-butenoyl) oxyethylsuccinic acid, 2-acryloyloxyethylphthalic acid, 2-methacryloyloxyethylphthalic acid, 2-acryloyloxypropylphthalic acid, 2-methacryloyloxypropylphthalic acid and 3-acryloyloxypropylphthalic acid Having an ester group, carbocyclic carboxylic acids such as benzoic acid, toluic acid and salicylic acid, heterocyclic carboxylic acids such as furancarboxylic acid, thiophenecarboxylic acid and pyridinecarboxylic acid, and polymers such as polyacrylic acid and polymethacrylic acid Examples thereof include carboxylic acids, and one or more of these are used. The molecular weight of the organic carboxylic acid is preferably less than 10,000.

As the polyvalent metal constituting the polyvalent metal compound (B), alkaline earth metals such as beryllium, magnesium, calcium and barium; transition metals such as manganese, cobalt, nickel, zinc and cadmium. Group; Group IIIB metals such as aluminum and gallium. Of these, zinc and calcium are particularly preferably used. Moreover, the polyvalent metal constituting these polyvalent metal compounds may be used alone or in combination of two or more.

In the present invention, the above mixture has a total amount of 1 of the vinyl monomer (A) and the polyvalent metal compound (B).
The organic carboxylic acid (C) having no polymerizable double bond is 0.1 to 10 mol%, preferably 0.5 to 100 mol%.
It may further contain 8 mol%. As a result, the polyvalent metal salt in a form in which an organic carboxylic acid having no polymerizable double bond is bound to a part of the polymerizable unsaturated carboxylic acid polyvalent metal salt is a polyvalent metal salt soluble in all monomer solutions. Since it is produced in the form of a polymer, the polymer formed by the polymerization of this mixture contains a high concentration of a polyvalent metal salt, and cross-linking by the polyvalent metal salt between linear polymers occurs. At this time, since a part of the crosslinked structure can be replaced with a non-crosslinked branched linear polymer by an organic carboxylic acid partially having no polymerizable double bond, in the hot-melt pressure-sensitive adhesive composition comprising this polymer, When plasticizing is intended, heat resistance and cohesive force, adhesiveness such as tackiness and tack, and moldability can be expressed while maintaining various characteristics excellent in viscosity characteristics upon heating and melting. The balance of molding processability is also sufficient.

When the content of the organic carboxylic acid (C) having no polymerizable double bond is more than 10 mol%,
Performance such as heat resistance derived from polyvalent metal becomes insufficient,
There are problems that an insoluble matter is generated in the mixture, uniform polymerization cannot be performed, and the obtained thermoplastic hot melt type pressure-sensitive adhesive composition becomes opaque. Also, 0.
When it is less than 1 mol%, the viscosity characteristics of the hot-melt pressure-sensitive adhesive composition at the time of heating and melting and the pressure-sensitive adhesive characteristics such as adhesive strength and tack cannot be further improved, and the thermoplastic processing is intended. The balance between heat resistance and molding processability may become insufficient. The method of adding the organic carboxylic acid (C) having no polymerizable double bond is not particularly limited, but a method of adding a predetermined amount into the polymerization system during the polymerization to form a mixture, and a vinyl monomer in advance Any method may be used in which a predetermined amount is added after the polyvalent metal compound (B) is dissolved in (A) to form a mixture, but the polyvalent metal compound (B) is added to the vinyl monomer (A).
It is preferable to add a predetermined amount after the is dissolved.

The organic carboxylic acid (C) having no polymerizable double bond is, for example, formic acid, acetic acid, propionic acid, hexanoic acid, butyric acid, isobutyric acid, valeric acid, isovaleric acid, crotonic acid, nagrin. Acid, senecionic acid, octylic acid, stearic acid, palmitic acid, linoleic acid, naphthenic acid and other saturated aliphatic monocarboxylic acids, oxalic acid, malonic acid, succinic acid and other saturated aliphatic dicarboxylic acids, cyclohexylcarboxylic acid, benzoic acid , Carbocyclic carboxylic acids such as toluic acid, salicylic acid, naphthoic acid, phthalic acid and cinnamic acid, heterocyclic carboxylic acids such as furancarboxylic acid, thiophenecarboxylic acid and pyridinecarboxylic acid, polyacrylic acid and polymethacrylic acid Molecular carboxylic acids, etc. are listed, and among these compounds, 1
Species or two or more species are used. Particularly preferred are saturated aliphatic monocarboxylic acids and carbocyclic carboxylic acids. Further, the organic carboxylic acid (C) having no polymerizable double bond
The molecular weight of is preferably less than 10,000. If the molecular weight exceeds 10,000, sufficient reactivity may not be exhibited due to steric hindrance or the like.

To improve the viscosity characteristics of the hot-melt type pressure-sensitive adhesive composition at the time of heating and melting and the pressure-sensitive adhesive characteristics such as adhesive strength and tack by selecting the type and ratio of the organic carboxylic acid (C) within the above range. You can

Next, the hot-melt pressure-sensitive adhesive composition according to the present invention is obtained by polymerizing a mixture prepared by dissolving the polyvalent metal compound (B) in the vinyl monomer (A). If By dissolving the polyvalent metal compound (B) in the vinyl monomer (A), the polyvalent metal compound (B) is soluble in all monomer solutions between the monomer having a carboxyl group and the polyvalent metal (hydr) oxide. This is to form a polymerizable unsaturated carboxylic acid polyvalent metal salt.

The means for forming the above mixture is not particularly limited, and for example, as in Example 1 described later, water is used as the main component of the vinyl monomer (A) not containing the monomer having a carboxyl group. The organic carboxylic acid polyvalent metal salt of the optional component of the polyvalent metal compound (B) is added and dissolved, and then the monomer having a carboxyl group and the essential component of the polyvalent metal compound (B) are added. A method in which a valent metal hydroxide and an organic carboxylic acid (C) having no polymerizable double bond are added at once and dissolved; as in Example 2 described later, vinyl containing no monomer having a carboxyl group. Water is added to the main component of the monomer (A), then an organic carboxylic acid polyvalent metal salt of an arbitrary component of the polyvalent metal compound (B) is added and dissolved, and then a monomer having a carboxyl group is added. Polyvalent metal compound (B)
A method of adding a polyvalent metal oxide as an essential component and an organic carboxylic acid (C) having no polymerizable double bond at once and dissolving them; as in Example 3 described later, a monomer having a carboxyl group A vinyl monomer (A) -free monomer containing a polyvalent metal compound (B), which is an essential component of the polyvalent metal hydroxide, is decomposed, and subsequently a monomer having a carboxyl group under heating and stirring. And an organic carboxylic acid (C) having no polymerizable double bond are added at one time and dissolved while continuing heating and stirring; vinyl containing no monomer having a carboxyl group as in Example 4 described later. A monomer having a carboxyl group as a main component of the monomer (A) and a polyvalent metal compound (B)
The polyvalent metal hydroxide, which is an essential component, and the organic carboxylic acid (C) having no polymerizable double bond are added at once, and the mixture is dissolved under heating with stirring, and the polyvalent metal compound (B) is optionally added. A method in which a polyvalent metal salt of an organic carboxylic acid as a component is added and dissolved; as in Example 5 described later, a vinyl monomer (A) not containing a monomer having a carboxyl group has a carboxyl group as a main component. A monomer, a polyvalent metal oxide, which is an essential component of the polyvalent metal compound (B), and an organic carboxylic acid (C) having no polymerizable double bond are added at once, and dissolved under heating with stirring, Further, various forming methods such as a method of adding and dissolving an organic carboxylic acid (C) having no polymerizable double bond can be appropriately selected and used.

Next, the hot-melt pressure-sensitive adhesive composition of the present invention comprises a polymer formed by polymerizing a mixture obtained by dissolving the polyvalent metal compound (B) in the vinyl monomer (A). Since the mixture is formed prior to initiating the polymerization. It is also possible to form a mixture by forming a mixture and compatibilizing the same at the time of polymerization to form a polymer, but in this case, a heterogeneous state easily occurs in the polymerization system, and the hot melt This is because the quality of the pressure-sensitive adhesive composition tends to vary. Further, when transparency or the like is required depending on the intended use, it is more preferable to make the mixture a transparent solution while heating and stirring as necessary. In the state of such a clear solution, a completely dissolved and insoluble mixture is formed,
This is because a hot-melt pressure-sensitive adhesive composition made of a polymer formed by polymerizing this can have excellent transparency and stable quality.

If desired, heating may be carried out when the polyvalent metal compound (B) is dissolved in the vinyl monomer (A) to form a mixture. The heating temperature in this case is usually in the range of 30 to 90 ° C., preferably 40 to 70 ° C., and the heating time is usually 0.2 to 2 hours, preferably 0.5 to 1 hour. When the heating temperature is lower than 30 ° C., the reactivity (solubility) of the polyvalent metal compound is extremely poor and it takes a long time for the reaction (dissolution), and the unreacted polyvalent metal compound (insoluble matter) is hot. Since it remains in the melt-type pressure-sensitive adhesive composition, mechanical properties and transparency are deteriorated, which is not preferable, and when the temperature exceeds 90 ° C, a part of the formed mixture may be modified or decomposed. However, it is not preferable because a part of the polymerization occurs and an inhomogeneous state occurs in the system. When the heating time is less than 0.2 hours, the reaction (dissolution) of the polyvalent metal compound is not completed, and the polyvalent metal salt to be added to the hot-melt pressure-sensitive adhesive composition is formed by the subsequent polymerization. Is insufficient, and unreacted polyvalent metal compound (insoluble matter) is contained in the hot-melt pressure-sensitive adhesive composition, which is not preferable because mechanical properties and transparency are deteriorated. If it exceeds 2 hours, the reaction (dissolution) has already been completed, and further heating is uneconomical with no corresponding effect.

Next, the above-mentioned mixture can be polymerized by a known polymerization method, but a radical polymerization method is preferably used.

The polymerization initiator added at the time of polymerization is
Usually, known free radical catalysts, for example, organic peroxides such as benzoyl peroxide, lauroyl peroxide, tert-butyl hydroxyperoxide, cumene peroxide, methyl ethyl ketone peroxide, tert-butyl perphthalate, and caproyl peroxide. Compounds, inorganic oxides such as potassium persulfate, sodium persulfate, hydrogen peroxide, azobisisobutyronitrile, azobisisobutyramide, 2,2 '
-Azobis (2,4-dimethylvaleronitrile), azobis (α-methylvaleronitrile), azobis (α-methylbutyronitrile), and other azo compounds can be mentioned, and one or two of these can be mentioned. The above can be used. These polymerization initiators can be appropriately used within the range of usually 0.01 to 10% by weight, preferably 0.1 to 5% by weight, based on the whole mixture. The polymerization initiator is 0.0
If it is less than 1% by weight, the concentration of the polymerization initiator in the polymerization system is not sufficient and the reaction yield in the entire system is low, which is not preferable. If it exceeds 10% by weight, the addition is justified. It is uneconomical because it cannot obtain the further effect of.

In the present invention, a chain of lauryl mercaptan, dodecyl mercaptan, 2-mercaptoethanol, 2-mercaptoacetic acid, carbon tetrachloride and carbon tetrabromide is used to control the molecular weight of the polymer formed by the polymerization. Transfer agents may be used.

For the polymerization of the above mixture, known polymerization forms such as a bulk polymerization method, a suspension polymerization method, an emulsion polymerization method and a solution polymerization method can be adopted. In particular, when the thermoplastic processing of a hot-melt type pressure-sensitive adhesive composition made of a polymer formed by polymerization of the mixture is intended, transparency can be obtained by using a cast polymerization method which is one of bulk polymerization methods. And it is preferable because it is easy to obtain a thermoplastic hot melt type pressure-sensitive adhesive composition excellent in molding processability. Then, various additives such as a suspending agent and an emulsifier can be used according to these polymerization forms, and the type and amount of the polymerization initiator and the chain transfer agent, the polymerization conditions such as the polymerization temperature and the pressure may be appropriately determined. Good.

The hot melt type adhesive composition of the present invention comprises:
Before or after the above-mentioned polymerization, if necessary, as a filler, for example, one or two kinds of carbon, fumed silica, wet silica, talc, clay-based filler, quartz powder, diatomaceous earth, etc. It may be made of a polymer formed by mixing and using the above.

In addition to the above, the hot-melt type pressure-sensitive adhesive composition of the present invention may be used as a plasticizer, for example, Comolec No. 2 oil, Sunper 2280, PW-3
It may be made of a polymer formed by mixing and using one kind or two or more kinds such as 80. In addition, as an anti-aging agent, Noward 455, Irganox 1010,
It may be made of a polymer formed by using one kind or a mixture of two or more kinds of Nocrac 224, Nocrac White, Nocrac 630F, Nocrac 810NA, Anticage OD and the like. Furthermore, examples of the dispersant include low-molecular-weight siloxane, silanol group-containing silane, alkoxysilane, and the like, and the dispersant may be made of a polymer formed by using one kind or a mixture of two or more kinds thereof. Further, it may be composed of a polymer formed by mixing and using various additives such as a colorant, a modifier, a stabilizer, a filler, and a release agent.

[0050]

The present invention is described in detail below with reference to examples, but the present invention is not limited to these.

Example 1 A mixed liquid of 100 g (0.78 mol) of n-butyl acrylate and 37 g (0.2 mol) of 2-ethylhexyl acrylate (the glass transition temperature of the polymer obtained from these monomers was calculated as- 60 ° C.), water was added and dissolved so that the water content was 0.18 g (0.01 mol) (the amount of water was the Karl Fischer moisture meter (MKS-3P type manufactured by Kyoto Electronics Manufacturing Co., Ltd.). ) Was measured).
Furthermore, zinc diacrylate 0.21 g (0.001 mol)
Was dissolved. 4.0 g of zinc hydroxide (0.04
Mol), methacrylic acid 3.4 g (0.04 mol) and hexanoic acid 4.8 g (0.04 mol) were added. To this mixture, 1.0 g of azobisisobutyronitrile as a radical polymerization initiator and 0.5 g of 1-dodecanethiol as a chain transfer agent were added and dissolved to prepare a mixture. This mixture was poured into a cell assembled using two glass plates and a Teflon gasket, polymerized at 60 ° C. for 3 hours, the casting resin was taken out, and after heating at 80 ° C. for 2 hours, the present invention was carried out. A hot-melt pressure-sensitive adhesive composition (hereinafter, referred to as pressure-sensitive adhesive (1)) was obtained. When the molecular weight of this pressure-sensitive adhesive (1) was measured using gel permeation chromatography (8010 type manufactured by Tosoh Corporation), the weight average molecular weight (hereinafter, referred to as Mw) was 190,000, and the number average molecular weight (hereinafter, Mn) was 80,000. This adhesive (1) was applied to a polyester film (PET, thickness 25μ
m), so that the coating thickness is 25 μm.
A sample tape (hereinafter, referred to as sample tape (1)) was obtained.

Example 2 n-Butyl acrylate (calculated glass transition temperature of the polymer obtained from this monomer is -54 ° C) 1
Water content is 0.18g for 24g (0.97mol)
Water was added and dissolved so as to be (0.01 mol). Furthermore, 6.2 g (0.01 mol) of zinc di (2-acryloyloxyethyl phthalate) was mixed and dissolved. 2.4 g (0.03 mol) of zinc oxide, 2.58 g (0.03 mol) of methacrylic acid and 3.0 g of isovaleric acid were added to this solution.
(0.03 mol) was added. To this mixture, 1.0 g of benzoyl peroxide as a radical polymerization initiator and 0.5 g of 1-dodecanethiol as a chain transfer agent were added and dissolved to prepare a mixture. This mixture was poured into a cell assembled using two glass plates and a Teflon gasket,
Polymerize at 0 ° C for 3 hours and then remove the casting resin
The hot-melt pressure-sensitive adhesive composition of the present invention (hereinafter referred to as the pressure-sensitive adhesive (2)) was obtained by heating at 2 ° C. for 2 hours. When the molecular weight of this pressure-sensitive adhesive (2) was measured by gel permeation chromatography (8010 type, manufactured by Tosoh Corporation), Mw was 180,000 and Mn was 80,000. This adhesive (2) was applied to a polyester film (PE
T, thickness 25 μm) to obtain a sample tape (hereinafter referred to as sample tape (2)).

Example 3 n-Butyl acrylate (calculated glass transition temperature of the polymer obtained from this monomer is -54 ° C) 1
21 g (0.95 mol) and 3.0 g of calcium hydroxide
(0.04 mol) was added and dispersed. The mixture was heated to 70 ° C., and 6.0 g of methacrylic acid (0.
072 mol) and 1.8 g (0.016 mol) of hexanoic acid were added at once. This mixed solution was heated and stirred at 70 ° C. for 30 minutes to form a uniform transparent solution. Azobisisobutyronitrile 1.0 was added to this solution as a radical polymerization initiator.
g and 0.5 g of 1-dodecanethiol as a chain transfer agent were added and dissolved to prepare a mixture. This mixture was poured into a cell assembled using two glass plates and a Teflon gasket, polymerized at 60 ° C. for 3 hours, the casting resin was taken out, and after heating at 80 ° C. for 2 hours, the present invention was carried out. A hot-melt pressure-sensitive adhesive composition (hereinafter referred to as pressure-sensitive adhesive (3)) was obtained. The molecular weight of this adhesive (3) was determined by gel permeation chromatography (8 manufactured by Tosoh Corporation).
010 type), Mw is 190,000, Mn
Was 100,000. This adhesive (3) is applied on a polyester film (PET, thickness 25 μm) with a thickness of 25 μm.
Was uniformly applied to obtain a sample tape (hereinafter referred to as sample tape (3)).

Example 4 A mixed solution of 97 g (0.76 mol) of n-butyl acrylate and 35 g (0.19 mol) of 2-ethylhexyl acrylate (the calculated glass transition temperature of a polymer obtained from these monomers is − 60 ° C) and zinc hydroxide 5.
0 g (0.05 mol) and methacrylic acid 3.1 g (0.0
36 mol) and 10.4 g of octanoic acid (0.072 mol) were added. This mixed solution was heated and stirred at 70 ° C. for 30 minutes to form a uniform transparent solution. 1.2 g (0.005 mol) of zinc dimethacrylate was further added to this solution. To this solution, 1.0 g of lauroyl peroxide as a radical polymerization initiator and 1.0 g of 1-dodecanethiol as a chain transfer agent were added and dissolved to prepare a mixture. This mixture was poured into a cell assembled using two glass plates and a Teflon gasket, polymerized at 60 ° C. for 3 hours, the casting resin was taken out, and after heating at 80 ° C. for 2 hours, the present invention was carried out. A hot-melt pressure-sensitive adhesive composition (hereinafter referred to as pressure-sensitive adhesive (4)) was obtained. The molecular weight of the adhesive (4) was measured by gel permeation chromatography (8010 type manufactured by Tosoh Corporation), and Mw was 1
The Mn was 0,000 and the Mn was 60,000. The pressure-sensitive adhesive (4) was uniformly applied onto a polyester film (PET, thickness 25 μm) so that the coating thickness was 25 μm to obtain a sample tape (hereinafter referred to as sample tape (4)).

Example 5 n-Butyl acrylate (calculated glass transition temperature of polymer obtained from this monomer is -54 ° C) 1
8.1 g of zinc oxide (0.10 mol) in 15 g (0.90 mol)
Mol) and 5.3 g (0.062 mol) of methacrylic acid and 6.1 g (0.06 mol) of isovaleric acid. This mixed solution was heated and stirred at 70 ° C. for 30 minutes to form a uniform transparent solution. 5.8 g of hexanoic acid was added to this solution.
(0.05 mol) was added. To this solution, 1.0 g of benzoyl peroxide as a radical polymerization initiator and 1.5 g of 1-dodecanethiol as a chain transfer agent were added and dissolved to prepare a mixture. This mixture was poured into a cell assembled using two glass plates and a Teflon gasket, and the temperature was 60 ° C.
After 3 hours of polymerization, the casting resin was taken out and heated at 80 ° C. for 2 hours to obtain a hot-melt pressure-sensitive adhesive composition of the present invention (hereinafter referred to as pressure-sensitive adhesive (5)). The molecular weight of this pressure-sensitive adhesive (5) was measured by gel permeation chromatography (8010 type manufactured by Tosoh Corporation), and Mw was 70,000 and Mn was 40,000. This adhesive (5) was applied to a polyester film (PE
T, thickness 25 μm) to obtain a sample tape (hereinafter referred to as sample tape (5)).

Comparative Example 1 0.24 g (0.001 mol) of zinc dimethacrylate was mixed and dissolved in 141 g (1.1 mol) of n-butyl acrylate. To this polymerizable mixture, 1.0 g of lauroyl peroxide as a radical polymerization initiator and 0.5 g of 1-dodecanethiol as a chain transfer agent were added and dissolved to prepare a mixture.
This mixture was poured into a cell assembled using two glass plates and a Teflon gasket, polymerized at 60 ° C for 3 hours, the casting resin was taken out, and after heating at 80 ° C for 2 hours, the adhesive for comparison was used. An agent composition (hereinafter, referred to as a comparative pressure-sensitive adhesive (1)) was obtained. The molecular weight of this pressure-sensitive adhesive for comparison (1) was measured by gel permeation chromatography (8010 type manufactured by Tosoh Corporation), and M was obtained.
The w was 200,000 and the Mn was 80,000. A polyester film (PET, thickness 25 μ
m), so that the coating thickness is 25 μm.
A comparative sample tape (hereinafter, referred to as comparative sample tape (1)) was obtained.

Comparative Example 2 2.6 g (0.03 mol) of methacrylic acid and 5.0 g of acrylic acid were added to 115 g (0.90 mol) of n-butyl acrylate.
g (0.07 mol) were mixed and dissolved. To this polymerizable mixture, 1.0 g of azobisisobutyronitrile as a radical polymerization initiator and 0.5 g of 1-dodecanethiol as a chain transfer agent were added and dissolved to prepare a mixture. This mixture was poured into a cell assembled using two glass plates and a Teflon gasket, polymerized at 60 ° C for 3 hours, the casting resin was taken out, and after heating at 80 ° C for 2 hours, the adhesive for comparison was used. An agent composition (hereinafter, referred to as a comparative pressure-sensitive adhesive (2)) was obtained. The molecular weight of this comparative adhesive (2)
Mw was 20 when measured using permeation chromatography (8010 type manufactured by Tosoh Corporation).
And Mn was 90,000. This comparative pressure-sensitive adhesive (2) was evenly applied on a polyester film (PET, thickness 25 μm) to a coating thickness of 25 μm, and a comparative sample tape (hereinafter referred to as comparative sample tape (2) To get).

Comparative Example 3 n-Butyl acrylate 103 g (0.80 mol), zinc oxide 24 g (0.30 mol) and methacrylic acid 25.5 g.
(0.30 mol) and 30 g (0.30 mol) of isovaleric acid were added. The mixture was heated and stirred at 70 ° C. for 30 minutes, but it did not become transparent and a precipitate remained. 1.0 g of benzoyl peroxide as a radical polymerization initiator was added to this mixed solution,
As a chain transfer agent, 0.5 g of 1-dodecanethiol was added and dissolved to prepare a mixture. This mixture was poured into a cell assembled using two glass plates and a Teflon gasket, polymerized at 60 ° C. for 3 hours, the casting resin was taken out, and after heating at 80 ° C. for 2 hours, precipitation occurred. Remained, and it was not possible to evaluate as a pressure-sensitive adhesive composition because it was not a polymer having a uniform composition.

Example 6 Sample tapes (1) to (5) obtained in Examples 1 to 5 and Comparative examples 1 to 2 and Comparative sample tapes (1) to (2)
The viscosity characteristics of the pressure-sensitive adhesives (1) to (5) of the present invention and the pressure-sensitive adhesives (1) to (2) for comparison of
The melt viscosity was evaluated. Specifically, the pressure-sensitive adhesives (1) to (5) of the present invention and the pressure-sensitive adhesives (1) to (2) for comparison were allowed to stand at 180 ° C. for 20 minutes, and then at that temperature, a B-type viscometer (BM manufactured by Tokimec Co., Ltd.). Type) was used to evaluate the melt viscosity.

Further, using the sample tapes (1) to (5) and the comparative sample tapes (1) to (2) obtained in Examples 1 to 5 and Comparative Examples 1 and 2, the adhesive of the present invention ( 1) ~
The heat resistance, cohesive strength, adhesive strength, and tack of (5) and the pressure-sensitive adhesives for comparison (1) and (2) were evaluated as follows.

The heat resistance was evaluated by the cohesive force at 80 ° C. Specifically, after attaching the sample tapes (1) to (5) and the comparative sample tapes (1) to (2) (25 mm × 25 mm) on a stainless steel plate (SUS304), one reciprocating pressure was applied with a 2 Kgf rubber roll. After leaving it at 80 ° C for 20 minutes, make the stainless plate vertical at that temperature and put 1kg on the lower end of the sample.
Was applied to evaluate the shift length after 24 hours.

The cohesive force was evaluated by the following method. Specifically, after attaching the sample tapes (1) to (5) and the comparative sample tapes (1) to (2) (25 mm × 25 mm) on a stainless steel plate (SUS304), one reciprocating pressure was applied with a 2 Kgf rubber roll. After standing for 20 minutes at 23 ° C., the stainless plate was made vertical at that temperature, a load of 1 kg was applied to the lower end of the sample, and the shift length after 24 hours was evaluated.

The adhesive strength was evaluated by the following method. Specifically, after attaching the sample tapes (1) to (5) and the comparative sample tapes (1) to (2) (25 mm × 20 mm) on a stainless steel plate (SUS304), the sample tape was pressed back and forth by a 2 Kgf rubber roll. After being left at 23 ° C. for 20 minutes, the peel strength when pulled in the 180 ° direction at a pulling speed of 300 mm / min in an atmosphere of 23 ° C. was evaluated.

The tack was evaluated by the following method. Specifically, the sample tapes (1) to (5) and the comparative sample tapes (1) to (2) were placed with the pressure-sensitive adhesive layer on the inclined surface with an inclination angle of 30 degrees, from the upper end of the sample tape. 1/32 inch to 32 in diameter from 10 cm above the slope
Steel balls having different diameters in the range of / 32 inch were rolled under a temperature atmosphere of 23 ° C. The maximum diameter of the steel ball that was stationary within 10 cm below the inclined surface from the upper end of the sample tape was evaluated.
Table 1 shows the results.

[0065]

[Table 1]

As is clear from Table 1, the pressure-sensitive adhesives (1) to (5) according to this example have a melt viscosity at 180 ° C. of 10000 or less and are excellent in coatability.
Even after the 4-hour cohesive strength test, almost no deviation was observed and the heat resistance was excellent. Furthermore, the adhesive properties such as cohesive strength at 23 ° C., adhesive strength, and tack were all excellent.

However, the comparative pressure-sensitive adhesives (1) to (2) are
The balance between melt viscosity and heat resistance at 180 ° C was extremely poor.

[0068]

The hot-melt pressure-sensitive adhesive composition of the present invention comprises a hot-melt pressure-sensitive adhesive composition obtained by directly adding to a monomer mixture or a polymer in the form of a metal salt and crosslinking the same as in the conventional method. Differently, it is characterized in that it is composed of a polymer formed by polymerization of a mixture in which components constituting a metal salt are dissolved in a monomer. That is, since the hot-melt pressure-sensitive adhesive composition is formed by synthesizing and polymerizing a metal salt soluble in all monomers from the components of the metal salt dissolved in the mixture, the hot-melt pressure-sensitive adhesive composition. Since the metal salt is introduced into the agent composition in a higher concentration and in a state where it is uniformly dispersed, excellent heat resistance and cohesive strength, adhesive properties such as adhesive strength and tack, and viscosity characteristics upon heating and melting It can be used in various fields such as light resistance, weather resistance, oil resistance, and transparency by adding water and various additives depending on the intended use. Can be achieved, for example,
Lighting parts, parts for vehicles such as automobiles, electric equipment parts,
It can be applied as a versatile material in a wide range of fields such as adhesive tapes, labels, and sheets used in building-related parts and instrument parts.

The hot-melt pressure-sensitive adhesive composition of the present invention is characterized by comprising a polymer formed by polymerizing a mixture containing an organic carboxylic acid having no double bond. Therefore, in addition to the effect of the hot-melt pressure-sensitive adhesive composition described above, a part of the crosslinked structure can be replaced with a non-crosslinked branched linear polymer,
In addition to maintaining heat resistance and cohesive strength, adhesive properties such as adhesive strength and tack, and viscosity properties during heating and melting, it can also exhibit excellent molding processability due to thermoplasticity, so it can be used in various fields. For example, it can be applied as a versatile material to a wide range of fields such as adhesive tapes, labels and sheets used for lighting parts, parts for transportation equipment such as automobiles, electric equipment parts, construction parts, instrument parts and the like.

Claims (4)

[Claims] 1. A polymer having a carboxyl group-containing monomer as an essential component and having a polymer glass transition temperature of −100 to −.
Vinyl monomer (A) in the range of 40 ° C 85.0-9
1 mol selected from oxides, hydroxides and organic carboxylates, as well as essentially containing 9.0 mol% of oxides and / or hydroxides.
Polyvalent metal compound (B) consisting of one or more species 1.0 to 15.0
A hot-melt pressure-sensitive adhesive composition composed of a polymer formed by polymerizing a mixture of the polyvalent metal compound (B) and the vinyl monomer (A), which is composed of 1% by mol of the polyvalent metal compound (B). 2. The vinyl monomer (A) is used as the mixture.
And an organic carboxylic acid (C) having no polymerizable double bond with respect to 100 mol% of the total amount of the polyvalent metal compound (B).
The hot melt adhesive composition according to claim 1, further containing 0.1 to 10 mol%. 3. The hot melt adhesive composition according to claim 1, wherein the vinyl monomer (A) contains butyl acrylate and / or 2-ethylhexyl acrylate as a main component. 4. The vinyl monomer (A) is used as the mixture.
And 0.1 to 3.0 mol% of water based on 100 mol% of the total amount of the polyvalent metal compound (B).
The hot-melt pressure-sensitive adhesive composition according to any one of items 1 to 3.