JPH08311426A - Hot-melt composition - Google Patents

Abstract

PURPOSE: To obtain a hot-melt compsn. excellent in adhesive properties by compounding an epoxidized block copolymer formed by epoxidizing conjugated diene units of a specific copolymer and an olefin polymer having a specified melt index. CONSTITUTION: An epoxidized block copolymer is produced by dissolving a block copolymer comprising polystyrene-polybutadiene-polystyrene blocks and conjugated diene blocks and having a number average mol.wt. of about 5,000-600,000 and a mol.wt. distribution of about 10 or lower in a solvent (e.g. ethyl acetate), adding an epoxidizing agent (e.g. peracetic acid) dropwise to the resultant soln. to react at about 0-20 deg.C, adding methanol etc. to the soln. after the completion of the reaction to deposit the reaction product, washing the product with water and drying it. About 80-20wt.% epoxidized block copolymer, about 20-80wt.% olefin copolymer (e.g. an ethylene-vinyl acetate copolymer) having a melt index of 100-2.000g/10min, and if necessary a tackifier (e.g. a coumarone resin) are melt kneaded at about 100-120 deg.C with a kneader etc. to give a hot-melt compsn.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is a hot-melt composition using a block copolymer having an epoxy-modified specific structure, which has excellent adhesive strength and further improves the fluidity because it contains a thermoplastic resin. Hot melt adhesive composition.

[0002]

2. Description of the Related Art Hot melt adhesives have a solid content of 100%.
It is a solventless adhesive that is solid at room temperature, and is heated and melted at the time of use to be applied to various adherends to be adhered and then solidified by cooling to develop an adhesive force. The hot melt adhesive has many advantages such as no environmental pollution, less risk of fire and the like, shortening of adhesive set time, and easy handling. Moreover, with the rapid spread of applicators, they are used in various fields such as bookbinding, packaging, and woodworking.

The hot melt adhesive is mainly composed of a base polymer (for example, a thermoplastic polymer such as an ethylene-vinyl acetate copolymer or an olefin copolymer such as an ethylene-acrylic acid ester copolymer) and an adhesive. It is composed of an imparting agent and a viscosity modifier. As the base polymer, an ethylene-vinyl acetate copolymer is generally used in terms of flexibility and cost. As the tackifier, natural resins such as rosin-based resins and terpene-based resins and their derivatives, and petroleum resins are often used. Also, various waxes are used as the viscosity modifier. As the wax, petroleum wax, mineral wax such as coal, and low molecular weight polyethylene wax are often used.

In recent years, a wide range of hot melt adhesives have been used in the fields of automobiles, packaging containers, structural fields and the like. However, the olefin-based copolymer has insufficient adhesion to a surface-resistant substrate and is insufficient. In addition, a hot melt adhesive using thermoplastic rubber requires a special applicator having high viscosity.

[0005]

The object of the present invention is to have excellent adhesiveness to an expanded surface base material, particularly to a plastics base material, a rubber base material, and to improve the fluidity of the adhesive in a molten state. A hot melt adhesive is provided.

[0006]

The hot melt composition of the present invention comprises an epoxy-modified block copolymer having a specific structure and an olefin polymer having a specific melt viscosity to achieve the above object. . Examples of the vinyl aromatic compound constituting the polymer block (A) mainly composed of the vinyl aromatic compound of the epoxy modified block copolymer used in the present invention include styrene, α-methylstyrene, vinyltoluene and p- One or more selected from tertiary butyl styrene, divinyl benzene, p-methyl styrene, 1,1-diphenyl styrene, etc., among which styrene is preferred. Examples of the conjugated diene compound (B) include butadiene, isoprene,
One or more of 1,8-pentadiene, 2,3-dimethyl-1,3-butadiene, piperiene, 3-butyl-1,3-octadiene, phenyl-1,3-butadiene, etc. It can be selected, and among them, butadiene, isoprene and combinations thereof are preferable. Here,
The block copolymer means a block copolymer, which is composed of a polymer block (A) mainly containing a vinyl aromatic compound and a polymer block (B) mainly containing a conjugated diene compound, and is a vinyl aromatic compound. And the conjugated diene compound has a copolymerization ratio of 5 / 95-70 / 30, particularly 10
A polymerization ratio of / 90 to 60/40 is preferable.

The number average molecular weight of the block copolymer used in the present invention is in the range of 5,000 to 600,000, preferably 10,000 to 500,000, and the molecular weight distribution [weight average molecular weight (Mw) and number average molecular weight (Mn) The ratio (Mw) / (Mn)] is 10 or less.
The molecular structure of the block polymer is linear, branched,
It may be radial or any combination thereof.

For example, A-B-A, B-A-A-B,
It is a vinyl aromatic compound-conjugated diene compound block polymer having a structure such as (AB-) Si and ABAA-BA. Further, the unsaturated bond of the conjugated diene compound of the block polymer may be partially hydrogenated.

As the method for producing the block copolymer used in the present invention, any production method can be used as long as it has the above structure. For example, Shokoku Sho 4
0-23798, JP-B-48-17979, JP-B-46-32415 and JP-B-56-28925, and vinyl aromatic compound-conjugated in an inert solvent using a lithium catalyst or the like. A diene compound block copolymer can be synthesized. Furthermore, Japanese Examined Japanese Patent Sho 4
According to the present invention, hydrogenation is carried out in the presence of a hydrogenation catalyst in an inert solvent according to the method described in JP-A No. 2-8704, JP-B No. 43-6636, or JP-A No. 59-138203. The partially hydrogenated block copolymer to be provided can be synthesized.

In the present invention, the epoxy modified block copolymer used in the present invention is obtained by epoxidizing the above block copolymer.

The epoxy modified block copolymer in the present invention can be obtained by reacting the above block copolymer with an epoxidizing agent such as hydroperoxides and peracetic acid in an inert solvent.

There is no strict limitation on the amount of epoxidizing agent and the optimum amount in each case depends on such variables as the particular epoxidizing agent used, the degree of epoxidation desired and the particular block copolymer used. Depends on

The inert solvent can be used for the purpose of decreasing the viscosity of the raw material and stabilizing it by diluting the epoxidizing agent. In the case of peracetic acid, aromatic compounds, ethers, esters and the like can be used. Can be used. Particularly preferred solvents are hexane, cyclohexane, toluene, benzene, ethyl acetate, carbon tetrachloride and chloroform. There are no strict rules for the epoxidation reaction conditions. The reaction temperature range that can be used depends on the reactivity of the epoxidizing agent used. For example, peracetic acid is 0 to 70 ° C.
The reaction is slow below 0 ° C, and peracetic acid is decomposed above 70 ° C. In the tertiary butyl hydroperoxide / molybdenum dioxide diacetylacetate system, which is an example of hydroperoxide, 20 to 150 ° C. is preferable for the same reason. No special manipulation of the reaction compound is necessary, and for example, the mixture may be stirred for 2 to 10 hours. Isolation of the obtained epoxy modified copolymer is carried out by a suitable method, for example, a method of precipitating with a poor solvent, a method of adding the polymer to hot water under stirring and distilling off the solvent, or a direct desolvation method. I can do things.

The degree of epoxidation of the epoxy modified block copolymer in the present invention is calculated by the following formula after titration with 0.1N hydrobromic acid.

Epoxy equivalent = 10,000 × [weight of epoxy modified block copolymer (g)] / [titration amount of hydrobromic acid (ml)] × [factor of hydrobromic acid] Epoxy modified block copolymer in the present invention The epoxy equivalent of the polymer is 200 to 5000 g / mol, preferably 250 to 1500 g / mol. When the epoxy equivalent is less than 200, the fluidity of the epoxy modified block copolymer is poor and the workability is poor. Further, when the epoxy equivalent exceeds 5,000, the adhesive property deteriorates.

The olefin copolymer used in the present invention includes high density polyethylene, medium density polyethylene, low density polyethylene, copolymers of ethylene and other α-olefins; polypropylene, propylene and other α-olefins. Copolymer with; polybutyne, poly-4-
Polyolefins such as methylpentene-1 or oligomers; ethylene-vinyl acetate copolymer, butyl rubber, butadiene rubber, propylene-butene copolymer, ethylene-acrylic acid ester copolymer, ethylene-methacrylic acid ester copolymer And so on. Each of these polymers may be contained alone, or 2
More than one species may be included.

The olefin copolymer used in the present invention preferably has a melt index of 400 to 2000 g / 10 min. If it is less than 400 g / 10 min, the fluidity of the adhesive in the molten state cannot be improved. In addition, 2000g
If it exceeds / 10 minutes, the cohesive force becomes insufficient, which is not suitable.

The composition of the resin composition of the present invention is as follows:
20 to 8 based on the total weight of (a) and (b)
0 to 20% (b) is contained. Preferably, (a) is contained in 25 to 75% and (b) is contained in 75 to 25%. When (b) is less than 20%, the viscosity of the obtained hot melt composition is too high to handle. Further, if (b) exceeds 80%, excellent adhesion cannot be obtained to the difficult surface substrate.

In addition, waxes may be added to the composition of the present invention in order to further adjust the viscosity in the hot melt state. The waxes may include paraffin wax, microcrystalline wax, animal wax, plant wax, mineral wax, synthetic wax and the like. Usually, the amount of wax added is 1) or 2) above.
It is up to 70 parts by weight with respect to 00 parts by weight. If it exceeds 70 parts by weight, the adhesive strength will decrease.

The composition of the present invention may further contain a tackifier to improve the adhesive strength and increase the initial adhesive strength. Tackifiers include, for example, terpene resins, coumarone resins, petroleum resins, styrene resins, phenol resins, rosin resins and the like. As a terpene resin,
Examples thereof include terpene resins, which are polymers of terpenes such as α-pinene, β-pinene, dipenter, limonene, myrcene, pornylene, and camphene, and phenol-modified terpene-based resins obtained by modifying these terpenes with phenols.

The coumarone-based resin includes, for example, coumarone-indene resin, phenol-modified coumarone-indene resin and the like.

Petroleum-based resins include, for example, styrene, α-,
Aliphatic petroleum-based resins, alicyclic petroleum-based resins or aromatic petroleum-based resins, and cyclopentadiene used alone or in combination with cyclopentadiene, using vinyl toluene, indene, methylindene, butadiene, isoprene, piperylene, pentylene, etc. Includes coalescence. Petroleum resins are often polymers using a C _{5 to} C ₉ fraction as the main component, and may be hydrogenated, such as hydrogenated cyclopentadiene resin.

Examples of the styrene resin include a low molecular weight homopolymer of styrene and a copolymer of styrene and α-methylstyrene, vinyltoluene, butadiene rubber and the like.

As the phenol resin, phenol,
Cresol, xylenol, resorcin, toluene, p
Reaction products of phenols such as -t-butylphenol and p-phenylphenol with aldehydes such as formaldehyde, acetaldehyde and furfural,
Examples include rosin-modified phenolic resin.

Examples of the rosin resin include rosins such as gum rosin and wood rosin, and derivatives thereof (for example,
Disproportionated rosins, hydrogenated rosins, dehydrogenated rosins, rosin esters such as rosin glycerin esters, rosin bentaerythritol esters, maleic acid adducts, rosin metal salts) and the like.

In the present invention, various antioxidants may be included in order to enhance the stability, particularly the thermal stability. These stabilizers are described in the book "Practical Handbook of Additives for Plastics and Rubbers" (published by Kagaku Kogyo Co. Ltd. 1970). 147-
304, P.I. It is also described in 1041 to 1054.
As the stabilizer, stabilizers generally used in thermoplastic resins, for example, 2,6-di-t-butyl-p-cresol, 2,2-methylbis (4methyl6-t-butylphenol), 4 , 4-butylidene bis (3-methyl-6)
-T-butylphenol), 4,4 thiobis (3-methyl-6-t-butylphenol), 2,2 thiobis (4methyl 6-t-butylphenol), stearyl-β-
(3,5-di-t-butyl-4-hydroxyphenol) propionate, tetrakis [methylene-3-
(3,5 Di-t-butyl-4-vidroxyphenyl) propionate] methane, triethylene glycol, bis [3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionate, 1,3,3 5-triethyl-
2,4,6 Tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, 1,1,3-2 methyl-5
-T-butylphenol) butane and other phenolic antioxidants; phenyl-α-naphthylamine, phenyl-
β-naphthylamine, N-phenyl-N′-cyclohexyl, p-phenylenediamine, N-isopropyl-N
′ -Phenyl-p-phenylenediamine and other amine stabilizers, triisodecyl phosphate, phosphorus stabilizers typified by 2,2-methylenebis (4,6-di-t-butylphenyl) octyl phosphate, etc. , 2,2'-thiobis (4-methyl-6-t-butylphenol) -containing sulfur-containing stabilizers, 2,5-di-t-amylhydroquinone-containing hydroquinone stabilizers, etc. In addition, 0 to 5 parts by weight may be added to 100 parts by weight. If the added amount of these stabilizers exceeds 5 parts by weight with respect to 100 parts by weight of the hot melt adhesive, the heat creep resistance is impaired and the cost becomes economically unpreferable. Further, these stabilizers may be used alone or in combination of two or more kinds, and if they are used in combination of two or more kinds, the thermal stability is likely to be further improved.

Further, the hot-melt adhesive of the present invention may contain other additives such as lubricants, pigments, dyes, inorganic fillers, fragrances, UV absorbers and oils within the range not impairing the object of the present invention. You may add.

The hot melt adhesive of the present invention can be produced by a conventional method, for example, by heating, melting and mixing the respective components. Usually, the heat-melt mixing is usually performed under normal pressure, but it may be performed under increased pressure or reduced pressure. The heat-melt mixing may be affected by the high melting point component, but usually 70
To 300 ° C., preferably about 80 to 250 ° C. The apparatus for heat-melt mixing is not limited as long as heating and mixing are possible. Usually, a tank equipped with a stirrer is often used. Also, an Intensive mixer,
A Banbury mixer, a super mixer, a Henschel mixer, etc. can be used. Further, the components of the hot-melt adhesive may be heated and melt-mixed by an extruder equipped with a screw, extruded from a mold and cooled to obtain an adhesive having a desired shape such as pellets, rods, and strings.

The present invention will be further described below with reference to examples, but the present invention is not limited thereto. In the following description, parts and% mean parts by weight and% by weight, respectively. The hot melt adhesive of the present invention can be formed into various shapes such as pellets, films, tapes, and strings. In addition, pellets, films, tapes,
The string-shaped hot melt adhesive may be pulverized by a known method.

The hot-melt adhesive of the present invention is generally prepared by heating and melting the hot-melt adhesive having the above-mentioned shape and coating and cooling the adherend with a hot-melt adhesive machine such as a nozzle type or roller type coater. Used for adhesion. Further, the hot melt adhesive of the present invention in the form of a film or powder may be sandwiched between adherends and heat-pressed for use.

[0031]

The hot-melt adhesive of the present invention has an epoxy group in its molecule, and therefore has excellent adhesiveness to a difficult surface substrate, particularly a plastic substrate or a rubber-based substrate, and a wide range of hot-melt adhesives. It can be applied to the adhesive field. Further, it has very good compatibility with an olefin polymer having high fluidity, and can be expected as an adhesive modifier for an olefin polymer.

[0032]

The present invention will be further described below with reference to examples, but the present invention is not limited thereto. In the following description, parts and% mean parts by weight and% by weight, respectively. [Example 1] 300 g of a polystyrene-polybutadiene-polystyrene block copolymer [manufactured by Nippon Synthetic Rubber Co., Ltd., trade name: TR-2000] in a jacketed reactor equipped with a stirrer, a reflux condenser and a thermometer. 1500 g of ethyl acetate was charged and dissolved. Then 30 of peracetic acid
169 g of a wt% ethyl acetate solution was continuously added dropwise, and an epoxidation reaction was carried out at 40 ° C. for 3 hours with stirring. The reaction liquid was returned to room temperature and taken out from the reactor, a large amount of methanol was added to precipitate a polymer, which was separated by filtration, washed with water, and dried to obtain an epoxy modified copolymer. The epoxy equivalent of the obtained epoxy modified copolymer was 470. 30 parts by weight of this epoxy modified block copolymer, 30 parts by weight of ethylene-vinyl acetate copolymer (Tosoh Corp .: Ultracene 7
22, MI = 400), 40 parts by weight of paraffin wax (Japan Seiro Co., Ltd .: paraffin 155F), 0.2 parts by weight of antioxidant (Ciba-Gaiki Co., Ltd .: Irg101).
0) was melt-mixed with a device such as a kneader at a temperature at which a curing reaction did not occur, usually at 100 to 120 ° C. to obtain a blend.

[Example 2] A block copolymer of polystyrene-polybutadiene-polystyrene was added to a jacketed reactor equipped with a stirrer, a reflux condenser, and a thermometer [manufactured by Nippon Synthetic Rubber Co., Ltd., trade name: TR-2400]. ] 300
g and 1500 g of ethyl acetate were charged and dissolved. Then, 113 g of a 30 wt% ethyl acetate solution of peracetic acid was continuously added dropwise, and an epoxidation reaction was carried out at 40 ° C. for 3 hours while stirring. The reaction solution was returned to room temperature and taken out from the reactor, a large amount of methanol was added to precipitate a polymer, and the polymer was separated by filtration and washed with water,
It was dried to obtain an epoxy modified copolymer. The epoxy equivalent of the obtained epoxy modified block copolymer was 698. 30 parts by weight of this epoxy modified copolymer, 30 parts by weight of ethylene-vinyl acetate copolymer (Tosoh Corporation: Ultrasen 725, MI = 1000), 40 parts by weight of microcrystalline wax (Japan Seiro Co., Ltd .: Hi)
-Mic-2065), and 0.2 parts by weight of antioxidant (Ciba-Gaiki Co., Ltd .: Irg1010) are used at a temperature at which a curing reaction does not occur at a temperature of 100 to 100% by using an apparatus such as a kneader.
A blend was obtained by melt mixing at 120 ° C.

Example 3 A block copolymer of polystyrene-polybutadiene-polystyrene in a jacketed reactor equipped with a stirrer, a reflux condenser and a thermometer [Shell Chemical Co., Ltd., trade name: Califlex D1122].
300 g and 1500 g of cyclohexanone were charged and dissolved. Then, 177 g of a 30 wt% ethyl acetate solution of peracetic acid
Was continuously added dropwise, and the epoxidation reaction was carried out at 40 ° C. for 3 hours with stirring. The reaction liquid was returned to room temperature and taken out from the reactor, a large amount of methanol was added to precipitate a polymer, which was separated by filtration, washed with water, and dried to obtain an epoxy modified copolymer. The epoxy equivalent of the obtained epoxy modified copolymer was 445.
Met. 54 parts by weight of this epoxy modified copolymer and 36 parts by weight of ethylene-vinyl acetate copolymer (Tosoh Corporation:
Ultrasen 1250, MI = 2000), 10 parts by weight of polyethylene wax (Chusei Wax Polymer Co., Ltd .: PEW-K2), 0.2 parts by weight of antioxidant (Ciba-Gaiki Co., Ltd .: Irg1010) were installed in a kneader. It is usually used at a temperature at which the curing reaction does not occur at 100
Blends were obtained by melt mixing at ~ 120 ° C.

[Example 4] A block copolymer of polystyrene-polybutadiene-polystyrene was added to a jacketed reactor equipped with a stirrer, a reflux condenser, and a thermometer [Shell Chemical Co., Ltd., trade name: Califlex TR111.
1] 300 g and cyclohexanone 1500 g were charged and dissolved. Then, a 30 wt% ethyl acetate solution of peracetic acid 22
2 g was continuously added dropwise, and the epoxidation reaction was carried out at 40 ° C. for 3 hours with stirring. The reaction solution is returned to room temperature and taken out from the reactor, a large amount of methanol is added to precipitate a polymer,
After separation by filtration, washing with water and drying, an epoxy modified copolymer was obtained.
The epoxy equivalent of the obtained epoxy modified copolymer was 4
It was 45. 64 parts by weight of this epoxy modified copolymer,
16 parts by weight of ethylene-ethyl acrylate copolymer (Nippon Unicar Co., Ltd .: MB-910, MI = 110)
0), 20 parts by weight of Sazol wax (Kato Yoko Co., Ltd .:
Sazol H1) and 3 parts by weight of antioxidant (Ciba-Gaiki Co., Ltd .: Irg1010) are used at a temperature at which curing reaction does not occur, using a device such as a kneader, and usually 100 to 120 ° C.
A blend was obtained by melt mixing at.

[Example 5] A block copolymer of polystyrene-polybutadiene-polystyrene was added to a jacketed reactor equipped with a stirrer, a reflux condenser, and a thermometer [Asahi Kasei Co., Ltd., trade name: Tuftec H-1041]. 400
g and 1,500 g of cyclohexanone were charged and dissolved. Then, 39 g of a 30 wt% ethyl acetate solution of peracetic acid was continuously added dropwise, and an epoxidation reaction was carried out at 50 ° C. for 3 hours with stirring. The reaction liquid was returned to room temperature, taken out from the reactor, washed with water, and the solvent was removed by steam stripping to obtain an epoxy modified copolymer. The epoxy equivalent of the obtained epoxy modified copolymer was 534. 14 parts by weight of this epoxy modified copolymer, 56 parts by weight of ethylene-methacrylic acid copolymer (Mitsui DuPont Polychemical Co., Ltd .: N-2050H, MI = 500), 30 parts by weight of paraffin wax (Nippon Seiro Co., Ltd .: paraffin) 115 F) and 5 parts by weight of an antioxidant (Ciba-Gaiki Co., Ltd .: Irg1010) using a device such as a kneader at a temperature at which a curing reaction does not occur, and usually 100 to 120 ° C.
A blend was obtained by melt mixing at.

Comparative Example A resin composition was obtained by changing the resin in the comparative example.

[Comparative Example 1] 30 parts by weight of block copolymer of polystyrene-polybutadiene-polystyrene [trade name: TR-2000 manufactured by Nippon Synthetic Rubber Co., Ltd.], 30 parts by weight of ethylene-methacrylic acid copolymer (Mitsui DuPont Poly. Chemical Co., Ltd .: N-2050H, MI = 50
0), 40 parts by weight of paraffin wax (Japan Seiro Co., Ltd .: Paraffin 155F), and 0.2 parts by weight of antioxidant (Ciba-Gaiki Co., Ltd .: Irg1010) do not cause a curing reaction by using an apparatus such as a kneader. Blends were obtained by melt mixing at temperature, usually 100-120 ° C.

Comparative Example 2 A block copolymer of polystyrene-polybutadiene-polystyrene was added to a jacketed reactor equipped with a stirrer, a reflux condenser, and a thermometer [trade name: TR-2000, manufactured by Nippon Synthetic Rubber Co., Ltd.]. ] 300
g and 1500 g of ethyl acetate were charged and dissolved. Then, 169 g of a 30 wt% ethyl acetate solution of peracetic acid was continuously added dropwise, and an epoxidation reaction was carried out at 40 ° C. for 3 hours while stirring. The reaction solution was returned to room temperature and taken out from the reactor, a large amount of methanol was added to precipitate a polymer, and the polymer was separated by filtration and washed with water,
It was dried to obtain an epoxy modified copolymer. The epoxy equivalent of the obtained epoxy modified copolymer was 470.
76 parts by weight of this epoxy modified copolymer, 4 parts by weight of ethylene-ethyl acrylate copolymer (Nippon Unicar Co., Ltd .: MB-730, MI = 20), 20 parts by weight of paraffin wax (Japan Seiro Co., Ltd .: Paraffin 15)
5F) and 0.2 parts by weight of antioxidant (Irg1010, Ciba-Gaiki Co., Ltd.) using a device such as a kneader at a temperature at which a curing reaction does not occur, and usually 100 to 120 ° C.
A blend was obtained by melt mixing at.

[Comparative Example 3] A block reactor of polystyrene-polybutadiene-polystyrene in a jacketed reactor equipped with a stirrer, a reflux condenser and a thermometer [manufactured by Nippon Synthetic Rubber Co., Ltd., trade name: TR-2000]. ] 300
g and 1500 g of ethyl acetate were charged and dissolved. Then, 169 g of a 30 wt% ethyl acetate solution of peracetic acid was continuously added dropwise, and an epoxidation reaction was carried out at 40 ° C. for 3 hours while stirring. The reaction solution was returned to room temperature and taken out from the reactor, a large amount of methanol was added to precipitate a polymer, and the polymer was separated by filtration and washed with water,
It was dried to obtain an epoxy modified copolymer. The epoxy equivalent of the obtained epoxy modified copolymer was 470.
0.5 parts by weight of this epoxy modified copolymer, 9.5 parts by weight of ethylene-vinyl acetate copolymer (Nippon Unicar Co., Ltd.):
MB-080, MI = 2500), 90 parts by weight of paraffin wax (Japan Seiro Co., Ltd .: Paraffin 155)
F), 0.2 parts by weight of antioxidant (Ciba-Gaiki Co., Ltd .:
Irg1010) was melt-mixed with a device such as a kneader at a temperature at which a curing reaction did not occur, usually at 100 to 120 ° C. to obtain a blend.

[Comparative Example 4] 30 parts by weight of block copolymer of polystyrene-polybutadiene-polystyrene [trade name: TR-2000 manufactured by Nippon Synthetic Rubber Co., Ltd.], 30 parts by weight of ethylene-vinyl acetate copolymer (Tosoh Corporation) Ultrasen 725, MI = 1000, 40 parts by weight of paraffin wax (Japan Seiro Co., Ltd .: Paraffin 15)
5F) and 0.2 parts by weight of antioxidant (Irg1010, Ciba-Gaiki Co., Ltd.) using a device such as a kneader at a temperature at which a curing reaction does not occur, and usually 100 to 120 ° C.
A blend was obtained by melt mixing at.

The hot melt adhesives obtained in Examples 1 to 5 and Comparative Examples 1 to 4 were subjected to the following items. The results are shown in the table.

(1) Melt viscosity (cps / 180 ° C.) (2) Shear strength is a value measured at 20 ° C.

Various difficult surface materials (25 mm x 150 mm)
Then, a hot melt adhesive is applied, and the difficult surface substrates are stuck together.

Hakuko Co., Ltd. using Hakko Melter Coating temperature: 180 ± 2 ° C, coating amount: 3 g / m Set time: 5 seconds, open time: 5 seconds Clamping load: 2 kgf, n = 3 The substrate is cured for one day. The shear strength was measured.

Tensile speed: 100 mm / min (3) Peeling condition of substrate Further, after measuring the shear strength, the peeling condition of the substrate was observed. In addition, when the resins are uniformly compatible with each other and sufficient adhesiveness is obtained, there is a problem in practical use because the adhesive portion of the peeled base material causes base material destruction or cohesive failure between resins. Does not happen.

[Table 1]

Claims (1)

[Claims] 1. A conjugated diene of a block copolymer comprising (a) a polymer block (A) mainly containing a vinyl aromatic compound and a polymer block (B) mainly containing a conjugated diene compound in the same molecule. Epoxy modified block copolymer obtained by epoxidizing unsaturated carbon as a component, and (b) JIS K
6730 has a melt index of 100 to 2
A hot melt composition comprising an olefin polymer at 000 g / 10 minutes.