JP2002356665A - Hot melt adhesive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot melt adhesive not spoiling the texture to be adhered and excellent in balance between the pressure-sensitive adhesive strength and a coating property. SOLUTION: The hot melt adhesive as a hardness of 4-20 tensile strength of 0.8-5 MPa at 23 deg.C and a melt viscosity of 1,000-6,000 mPa.s at 140 deg.C, which may comprise (A) one or more elastomers selected from the group consisting of a diene (co) polymer and ethylene-α-olefin copolymer, (B) an adhesive resin, and (C) a plasticizer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a hot melt adhesive. More specifically, the present invention relates to a hot melt adhesive which is particularly suitable for bonding a polyolefin resin molded product, has flexibility not to impair the texture of the resin molded product, and has excellent cohesion.

[0002]

2. Description of the Related Art Conventionally, styrene-ethylene-propylene-styrene block copolymer rubbers or styrene-butadiene-styrene block copolymers have been used as hot melt adhesives used for bonding polyolefin-based films, nonwoven fabrics, resin molded products and the like. A rubber compounded with a liquid plasticizer such as a tackifying resin component and a process oil, and other additives is known.
No. 60121).

[0003]

However, when the above is used as a hot-melt adhesive, the open time (the time from application to the time of bonding when bonding is possible) is increased or the melt viscosity is reduced. In such a case, problems such as a decrease in cohesive force and holding force and a decrease in adhesion to an adherend such as an olefin-based resin molded product occur. Further, when the cohesive force is improved, there is a problem that the flexibility is reduced and the texture of the resin molded product is impaired. That is, an object of the present invention is to provide a hot-melt adhesive having a good feeling of an adhesive body and an excellent balance between adhesive strength and coatability to various adherends such as polyolefin resin.

[0004]

Means for Solving the Problems The present inventors have solved the above problems and made intensive studies to obtain an adhesive having excellent adhesive strength and cohesive force and good flexibility. did. That is, the present invention has a hardness of 4 to
20, a tensile strength of 0.8 to 5 MPa, and a melt viscosity at 140 ° C. of 1,000 to 6,000.
0 mPa · s, hot melt adhesive (first invention); diene (co) polymer and ethylene-
A hot melt adhesive comprising one or more rubbers (A) selected from α-olefin copolymers, a tackifier resin (B) and a plasticizer (C), having the above-mentioned properties (second invention) And an adhesive body (third invention) in which polyolefin-based resin molded articles are bonded to each other or to another adherend with the hot melt adhesive.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The hot melt adhesive of the present invention
The hardness is 4 to 20, the tensile strength is 0.8 to 5 MPa, and the melt viscosity is 1,000 to 6,000 mPa ·
s. Only when it is within these ranges is it excellent in flexibility, adhesive strength and coatability (balanced)
A hot melt adhesive is obtained.

In the hot melt adhesive of the present invention, 2
The hardness at 3 ° C. is measured by a spring-type hardness test (A type) according to JIS K6301-1995. (Measurement condition of hardness test: Scale after 5 seconds by pressing the pressing surface vertically with a load of 9.81 N) Read.). The hardness at 23 ° C. is usually 4 to 20, preferably 5 to 18,
More preferably, it is 6-16. That is, the hardness is usually 4 or more, preferably 5 or more, and more preferably 6 or more. It is usually 20 or less, preferably 18 or less, and more preferably 16 or less. If the hardness is less than 4, the cohesive force of the hot melt adhesive tends to decrease, and if it exceeds 20, the texture and flexibility of the adhesive bonded with the hot melt adhesive tend to deteriorate.

[0007] In the hot melt adhesive of the present invention, the tensile strength is measured by a tensile test according to JIS K6301-1995 (measurement conditions for tensile strength test: dumbbell-shaped 3).
It measures at 23 degreeC and the tensile speed of 500 mm / min using a No. test piece. ). The tensile strength is usually 0.8 to 5 MPa, preferably 0.9 to 4 MPa, and more preferably 1 to 3 MPa. That is, the tensile strength (MPa) is usually 0.8 or more, preferably 0.9
Above, more preferably one or more. It is usually 5 or less, preferably 4 or less, and more preferably 3 or less. If the tensile strength is less than 0.8 MPa, the cohesive strength of the hot melt adhesive tends to decrease, and if it exceeds 5 MPa, the melt viscosity tends to increase and the coatability tends to decrease.

[0008] In the hot melt adhesive of the present invention, 1
The melt viscosity at 40 ° C. is measured by the following method. Measurement method: Approximately 8 in a test tube with an inner diameter of 16 mm and a height of 105 mm
g of the sample and put in an oil bath at 140 ° C. for 20 minutes.
After adjusting the temperature, an SB viscometer (JIS K7117-198)
7. Set SB4 spindle, for example, BL viscometer and No. 4 rotor manufactured by Toki Sangyo Co., Ltd.), adjust the temperature for further 10 minutes, rotate the rotor at 60 rpm, and melt viscosity after 10 minutes. Read. Hereinafter, the melt viscosity at 140 ° C. is referred to as a 140 ° C. melt viscosity. 140 ° C
The melt viscosity is usually from 1,000 to 6,000 mPa · s, preferably from 1,500 to 5,800 mPa · s, and more preferably from 2,000 to 5,500 mPa · s.
s. That is, 140 ° C. melt viscosity (Pa · s)
Is usually 1,000 or more, preferably 1,500
The number is more preferably 2,000 or more. It is usually 6,000 or less, preferably 5,800 or less,
More preferably, it is 5,500 or less. When the melt viscosity at 140 ° C. is less than 1,000 mPa · s, the cohesive strength of the hot melt adhesive tends to decrease, and
If it exceeds a · s, the coatability tends to decrease.

In a preferred embodiment of the first invention, at least one rubber (A) selected from a diene (co) polymer and an ethylene-α-olefin copolymer, a tackifier resin (B), and a plasticizer (C) (A second invention).

The rubber (A) constituting the hot melt adhesive of the present invention (second invention) is at least one rubber selected from diene (co) polymers and ethylene-α-olefin copolymers. The diene (co) polymer has 4 to 18 carbon atoms.
(For example, butadiene, isoprene, etc.) or other monomer (weight ratio of diene to other monomer: 0.1 to 100: 0 to 99.9) as a structural unit. (Co) polymers and their hydrogenated products are included. Other monomers include aromatic vinyl monomers such as styrene; olefins (2-8 carbon atoms) such as ethylene and propylene; unsaturated nitriles such as acrylonitrile.

Specific examples of the diene (co) polymer include butadiene rubber, isoprene rubber, natural rubber, butyl rubber, nitrile rubber, styrene-butadiene block copolymer rubber (SBS), and styrene-isoprene block copolymer rubber (SIS). ), A styrene-butadiene random copolymer rubber (SBR), a hydrogenated product obtained by partially or entirely hydrogenating the diene portion of a diene (co) polymer rubber [styrene- (ethylene-propylene) block copolymer rubber (S
EPS; hydrogenated SIS), styrene- (ethylene-
Butene) block copolymer rubber (SEBS; hydrogenated SBS), hydrogenated SBR and the like].

Specific examples of the ethylene-α-olefin copolymer include ethylene and α-olefin (having 3 to 18 carbon atoms:
For example, copolymer rubber of propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, etc. (weight ratio of ethylene to α-olefin of 0.1 to 95: 5 to 99.9),
Ethylene, α-olefin and non-conjugated diene (carbon number 4-1)
8: Terpolymer rubber (for example, ethylidene norbornene, dicyclopentadiene, or the like) (weight ratio of ethylene, α-olefin, and non-conjugated diene 30 to 90: 5 to 80: 0.1)
To 30). Among these, preferred are diene (co) polymers and hydrogenated products thereof, and particularly preferred are SBS, SIS, SEPS and SEB.
S.

The rubber (A) preferably has a melt index of 0.01 to 300, more preferably 0.1, according to the ASTM D1238-G method (200 ° C., 5,000 g).
~ 100. That is, the melt index of (A) is preferably 0.01 or more, more preferably 0.1.
1 or more. Also, it is preferably 300 or less, more preferably 100 or less. By setting the melt index of (A) within the above range, a hot melt adhesive having a better balance between cohesive strength (tensile strength) and adhesive processability (melt viscosity) can be obtained.

As the tackifying resin (B) constituting the hot melt adhesive of the present invention (second invention), a known plasticizer {adhesion technology 20, (2), 13 (2000), etc.} is used. For example, rosin, rosin derivative resin [for example, polymerized rosin, rosin ester and the like. Number average molecular weight (hereinafter referred to as Mn) 200 to 1,000], terpene-based resin (for example, (co) polymers such as α-pinene, β-pinene, limonene, and modified phenols thereof). Mn
300-1300], coumarone-indene resin, petroleum resin [for example, (co) polymers such as C5 cut, C9 cut, C5 / C9 cut, dicyclopentadiene and the like. Mn300 ~
1200], a styrene-based resin [eg, a (co) polymer such as styrene, α-methylstyrene,
n is 200 to 1,000 and the glass transition temperature (hereinafter, referred to as
Tg) of 40 ° C. or higher], xylene-based resin (for example, xylene-formaldehyde resin, etc .; Mn3)
00 to 3,000), a phenolic resin (for example, phenol-xylene-formaldehyde resin, etc .; Mn300)
To 3,000) and one or more resins selected from hydrogenated products of these resins. Of these, preferred are hydrogenated terpene resins and hydrogenated petroleum resins from the viewpoint of thermal stability, odor and hue, and particularly preferred are C9 fraction and C5 / C9 fraction ( It is a hydrogenated product of a (co) polymerized petroleum resin and a hydrogenated product of a dicyclopentadiene-based (co) polymerized petroleum resin. The number average molecular weight (Mn) and the weight average molecular weight (hereinafter, referred to as Mw) described above and below are values determined by gel permeation chromatography (GPC) using polystyrene as a standard.

As the plasticizer (C) constituting the hot melt adhesive of the present invention (the second invention), known plasticizers (adhesion techniques 20, (2), 21 (2000), etc.) can be used. For example, paraffinic, naphthenic or aromatic process oils; liquid resins such as liquid polybutene, liquid polybutadiene, and liquid polyisoprene (Mw = 30)
Hydrogenated forms of these liquid resins; natural or synthetic waxes [paraffin wax, microcrystalline wax, low molecular weight polyolefin wax (Mw = 1,000-30,000), etc.]; Mixtures of two or more are mentioned. Among these, preferred are paraffin-based process oils from the viewpoint of obtaining a composition having excellent heat stability and weather resistance,
Naphthenic process oils and their combination.

The content of (A) based on the total weight of rubber (A), tackifying resin (B) and plasticizer (C) constituting the hot melt adhesive of the present invention (second invention) is (A) to (A).
Based on the weight of (C), from the viewpoint of cohesive strength and melt viscosity, preferably 5 to 50% by weight, more preferably 8 to 50% by weight.
It is 45% by weight, particularly preferably 10 to 40% by weight.
That is, the content (% by weight) of (A) is preferably 5 or more, more preferably 8 or more, and particularly preferably 10 or more. It is preferably 50 or less, more preferably 4 or less.
It is 5 or less, particularly preferably 40 or less. The content of the tackifier resin (B) is preferably from 30 to 75% by weight based on the total weight of (A) to (C), from the viewpoint of adhesive strength.
More preferably 35 to 70% by weight, particularly preferably 4 to 70% by weight.
0 to 65% by weight. That is, the content of (B) is 3
It is preferably 0 or more, more preferably 35 or more, particularly preferably 40 or more. It is preferably at most 75, more preferably at most 70, particularly preferably at most 65. The content of the plasticizer (C) is preferably 1 to 50% by weight, more preferably 3 to 45% by weight, and more preferably 3 to 45% by weight, based on the total weight of (A) to (C), from the viewpoint of cohesive strength and melt viscosity.
４０40% by weight. That is, the content of the plasticizer (C) is preferably 1 or more, more preferably 3 or more, and particularly preferably 5 or more. It is preferably at most 50, more preferably at most 45, particularly preferably at most 40.

In the hot melt adhesive of the present invention, 1
The loss on heating after 3 hours in a 50 ° C. air atmosphere is 0.
It is preferably from 0.01 to 2.00% by weight, more preferably from 0.05 to 1.90% by weight, particularly preferably from 0.10 to 1.80% by weight. That is, the heat loss (% by weight) is preferably 0.01 or more, more preferably 0.05 or more, and particularly preferably 0.10 or more. It is preferably at most 2.00, more preferably at most 1.90, particularly preferably at most 1.80. When the weight loss on heating is less than 0.01% by weight, a low molecular weight component is insufficient, and sufficient adhesiveness tends to be hardly obtained.
If the content exceeds% by weight, volatile components increase, and odor and mist tend to increase during melting, and the adhesiveness tends to decrease.

Method for measuring loss on heating: An aluminum dish having a diameter of 50 mm and a depth of 20 mm is precisely weighed (the weight of the aluminum dish is measured as W ₁
g. ). A sample of about 2 g is precisely weighed and weighed on an aluminum dish (the weight of the sample is defined as W ₂ g). The aluminum dish containing the sample is placed in a 150 ° C circulating air dryer [eg, S
PHH200 type safety oven; manufactured by Tabai Espec Co.], and placed in an air atmosphere. After leaving it for 3 hours, it is taken out, cooled in a desiccator for 30 minutes, and then precisely weighed (weight is W ₃ g). The heating loss is obtained from the following equation. Heating loss = 100 ｛(W ₁ + W ₂ ) −W ₃ ｝ / W ₂

The hot melt adhesive of the present invention contains rubber (A), tackifier resin (B), plasticizer (C) and copolymer (D) as components for adjusting hardness, tensile strength and melt viscosity. ) And (D) a (co) polymer (E) having a higher Tg. In the above and below, Tg is measured by a differential scanning calorimetry (DSC) method.

The hardness can be adjusted mainly by the rubber (A). When the content of (A) is increased, the hardness tends to decrease. The tensile strength and hardness can be adjusted mainly by the tackifier resin (B). Raise the Tg of (B),
Alternatively, when the content of (B) is increased, the tensile strength and the hardness tend to increase. The melt viscosity can be adjusted mainly by the plasticizer (C). When the content of (C) is increased, the melt viscosity tends to decrease. The tensile strength can be adjusted mainly by the copolymer (D). By adjusting the SP value of (D) and increasing the compatibility with rubber (A), etc.,
Tensile strength tends to increase. The tensile strength can be adjusted mainly by the (co) polymer (E). (E) T
Increasing g tends to increase tensile strength without increasing hardness.

The copolymer (D) comprises an aromatic vinyl monomer (d1), an aliphatic or alicyclic unsaturated hydrocarbon having 4 to 20 carbon atoms (d2) and / or an alkyl or alkenyl group having carbon atoms of 4 to 24 alkyl or alkenyl (meth) acrylates (d3) are used as constituent monomers. As the aromatic vinyl monomer (d1) constituting the copolymer (D), for example, styrene, α-methylstyrene and styrene derivatives [for example, alkylstyrene having 1 to 4 or more carbon atoms of an alkyl group (vinyltoluene, Ethylstyrene, t-butylstyrene, etc.), halogenated styrene (eg, chlorostyrene, bromostyrene, fluorostyrene, etc.), amino group-containing styrene (eg, N, N-diethylaminostyrene, etc.)
Is mentioned. Preferred among these are α-methylstyrene and styrene, more preferably styrene.

Specific examples of the aliphatic or alicyclic unsaturated hydrocarbon (d2) having 4 to 20 (preferably 4 to 16) carbon atoms include aliphatic unsaturated hydrocarbons [monoolefin (for example, 1-butene, 4-methyl-1-pentene, 1-pentene, 2-pentene, 1-octene, 1-decene, 1-
Dodecene, etc.), alkadienes (eg butadiene, isoprene, 2,3-dimethyl-1,3-butadiene,
1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, 1,4-hexadiene,
4,5-diethyl-1,3-octadiene, 3-butyl-1,3-octadiene, etc.)]; alicyclic unsaturated hydrocarbon [(di) cycloalkadiene (eg, cyclopentadiene, dicyclopentadiene, methylcyclo Pentadiene, ethylidene norbornene, vinylidene norbornene, etc.]; and mixtures of two or more of these. Of these, more preferred are those having 4 to 4 carbon atoms.
12 aliphatic dienes (alkadienes) and 5 to 5 carbon atoms
Fourteen alicyclic dienes ((di) cycloalkadiene), particularly preferred are butadiene, dicyclopentadiene and ethylidene norbornene.

Specific examples of the alkyl or alkenyl (meth) acrylate (d3) having 4 to 24 carbon atoms in the alkyl or alkenyl group include butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate,
Lauryl (meth) acrylate, myristyl (meth) acrylate, stearyl (meth) acrylate, and oleyl (meth) acrylate. Of these, preferred are those having 12 to 18 carbon atoms in the alkyl group.
And particularly preferred is stearyl (meth) acrylate.

The copolymer (D) may have another monomer (d4) as necessary in addition to (d1) and (d2) and / or (d3) as constituent monomers. . As a specific example of (d4), a hydroxyl group-containing (meth) acrylate [(meth) acrylate having 4 to 10 carbon atoms of hydroxyalkanol, for example, 2-
Hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, mono (meth) acrylate of polyoxyalkylene (2-4 carbon atoms) glycol (polymerization degree 2-10 or more), etc .; amino group-containing ( Meth) acrylate [dialkyl (C1 to C1)
10) Aminoalkyl (2 to 10 carbon atoms) (meth) acrylate, such as dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate and the like]; unsaturated carboxylic acids [3 to 22 carbon atoms, monocarboxylic acid, for example; (Meth) acrylic acid, (iso) crotonic acid and cinnamic acid, dicarboxylic acids such as maleic acid, fumaric acid, itaconic acid, and monoalkyl (1-20 carbon atoms) of these dicarboxylic acids Esters and the like]; (meth) acrylates other than the above (d3) [for example, alkyl (meth) acrylates having an alkyl group having 1 to 3 carbon atoms [methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, etc. Alicyclic (di) cycloalkyl (meth) acrylate [C 8 16, for example, cyclohexyl (meth) acrylate, dicyclohexyl (meth) acrylate, etc.), aralkyl (meth) acrylate [9 to 21 carbon atoms, such as benzyl (meth) acrylate, etc.]; epoxy group-containing (meth) acrylate [carbon Formulas 2 to 18, for example, glycidyl (meth) acrylate etc.]; dialkyl (C1 to C20) ester of the above unsaturated dicarboxylic acid [C6 to C44, for example diethyl malate, dibutyl fumarate, etc.]; amide group or Imide group-containing monomer, for example, an imidized product of the above unsaturated dicarboxylic acid [C4-20, for example, maleimide,
N-methylmaleimide, N-butylmaleimide, N-phenylmaleimide, etc.] Amide of the above-mentioned unsaturated monocarboxylic acid [for example, (meth) acrylamide mono- and dialkyl (C1-10) aminoalkyl (C2-C2) 10) (meth) acrylamide]; a polyfunctional aromatic vinyl monomer (for example, divinylbenzene and the like);
Polyfunctional (meth) acrylate monomer [compound having two (meth) acryloyl groups in one molecule, such as di (meth) acrylate of neopentyl glycol], three (meth) acryloyl groups in one molecule Compounds having the above [for example, trimethylolpropane tri (meth) acrylate, pentaerythritol tri-
Or tetra- (meth) acrylate, etc.]; and a mixture of two or more of these. Preferred among these are unsaturated carboxylic acids, (meth) acrylates having 1 to 3 carbon atoms in the alkyl group and dialkyl esters of unsaturated dicarboxylic acids, more preferably (meth) acrylic acid, maleic anhydride, ethyl Methacrylate and dialkyl maleate (having 1 to 2 carbon atoms)
0) It is an ester.

The content of (d1) constituting the copolymer (D) is preferably from 25 to 85% by weight, more preferably 3 to 85% by weight, based on the weight of (D), from the viewpoint of cohesive strength and flexibility.
5 to 75% by weight. That is, the content (% by weight) of (d1) is preferably 25 or more, and more preferably 35% or more.
That is all. It is preferably at most 85, more preferably at most 75. The content of (d2) is preferably from 15 to 75% by weight, more preferably from 25 to 65% by weight, based on the weight of (D), from the viewpoint of cohesive strength and plasticizer retention.
It is. That is, the content (% by weight) of (d2) is 15%.
It is preferably at least 25, and more preferably at least 25. It is preferably at most 75, more preferably at most 65. The content of (d3) is preferably from 15 to 75% by weight, more preferably from 25 to 65% by weight, based on the weight of (D), from the viewpoint of cohesive strength and plasticizer retention. That is, the content (% by weight) of (d3) is preferably 15 or more, and more preferably 25 or more. It is preferably at most 75, more preferably at most 65. When other monomers (d4) are used, the content of (d4) is
From the viewpoint of compatibility with the rubber (A) and the like, it is preferably 0.01 to 10% by weight, more preferably 0.1 to 5% by weight, based on the weight of (D).

The copolymer (D) can be obtained by polymerizing the above-mentioned constituent monomers by a known method such as radical polymerization, thermal polymerization, or cationic polymerization. The resulting polymers include random, block, and graft polymers. Although the production method is not particularly limited, for example, the following radical polymerization method can be exemplified.

(1) A monomer is continuously or intermittently supplied to a heated solvent in the presence of a polymerization initiator. After the polymerization is completed, the solvent and, if necessary, unreacted monomers are distilled off under normal pressure or reduced pressure. A method for obtaining a copolymer (solution polymerization method). Solvents used for solution polymerization include aromatic hydrocarbons (toluene, xylene, cumene, etc.), aliphatic hydrocarbons (n
-Hexane, n-octane, n-decane, etc.), alicyclic hydrocarbons (cyclohexane, methylcyclohexane, etc.), halogen-containing systems (chloroform, carbon tetrachloride, dichloroethane, etc.), ketones (acetone, methyl ethyl leketone, etc.) , Ether (dioxane, dibenzyl ether), ester (ethyl acetate, isopropyl acetate,
Butyl acetate) and the like.

(2) A polymerization initiator is added to a solution obtained by dissolving a monomer alone or a copolymer obtained by pre-polymerization in a monomer, and the resulting mixture is heated and polymerized. A method of obtaining a copolymer by distillation under reduced pressure (bulk polymerization method).

(3) 1 selected from (A), (B), (C) and (E) which are constituents of the hot melt adhesive
In the presence of a polymerization initiator, a monomer is continuously or intermittently fed into a melt of one or more kinds or a solution obtained by adding the above-mentioned solvent to the melt to carry out polymerization. A method in which a reaction monomer is distilled off under normal pressure or reduced pressure to obtain a mixture comprising a copolymer and other components (coexistence polymerization method).

The polymerization temperature in the above radical polymerization is 80
The temperature is preferably in the range of -240 ° C, and can be suitably selected according to the type and amount of the polymerization initiator to be used and the intended molecular weight. The end point of the reaction can be confirmed by measuring the amount of unreacted monomer at the time of polymerization using gas chromatography. The temperature at which the solvent or unreacted monomer is distilled off varies depending on the type of the monomer.
~ 200 ° C is preferred. Among the radical polymerization methods of the copolymer (D), the coexistence polymerization method is preferred from the viewpoint of compatibility.

Examples of the polymerization initiator used for producing the copolymer (D) include azo polymerization initiators and organic peroxide polymerization initiators usually used for radical polymerization. Examples of the azo polymerization initiator include, for example, 2,2 ′
-Azobisisobutyronitrile, 2,2'-azobis (2,4 dimethylvaleronitrile), 2,2'-azobis (2-methylbutyronitrile) and the like. Examples of the organic peroxide-based polymerization initiator include peroxyketal [2,2-bis (4,4-di-t-butylperoxycyclohexyl) propane, 1,1 bis (t-butylperoxy) cyclohexane, 1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane)], hydroperoxide (such as t-butylhydroperoxide), dialkyl (having 1 to 1 carbon atoms)
12) peroxides (such as di-t-butyl peroxide and dicumyl peroxide), diacyl peroxides (such as lauroyl peroxide, stearoyl peroxide, and benzoyl peroxide), and peroxyesters (such as t-butylperoxybenzoate). t
-Hexyl peroxyisopropyl monocarbonate,
Organic peroxides such as di-t-butylperoxyhexahydroterephthalate) and peroxydicarbonate (such as di-n-propylperoxydicarbonate). Preferred among these are organic peroxide-based polymerization initiators, more preferred are dialkyl peroxides and peroxyesters, and particularly preferred are di-t-butyl peroxide, dicumyl peroxide and t-butyl peroxide. Benzoate. The amount of the polymerization initiator used is preferably from 0.01 to 20% by weight, more preferably from 0.05 to 15% by weight, based on the total weight of the monomers. That is, the amount (% by weight) of the polymerization initiator used is preferably 0.01 or more, and more preferably 0.05 or more. Moreover, it is preferably 20 or less, more preferably 15 or less.

In the production of the copolymer (D), a chain transfer agent can be used if necessary to adjust the molecular weight. Examples of chain transfer agents include α-olefins (eg, 1-dodecene, etc.), mercaptans (eg, t-butyl mercaptan, n-dodecyl mercaptan, etc.), disulfides (eg, bis-2-amino-phenyl disulfide, diisopropyl xantogen disulfide). And the like, diazothioether (eg, p-methoxyphenyldiazothio-2-naphthyl ether, etc.), organic halides (eg, carbon tetrachloride, carbon tetrabromide, chloroform, etc.) and the like. The thing of 01 or more is preferable. When a chain transfer agent is used, the amount of the chain transfer agent used is 10% by weight based on the total weight of the monomers.
The following is preferred, and more preferably 0.01 to 5% by weight
It is. That is, the amount (% by weight) of the chain transfer agent used is
It is preferably 10 or less, more preferably 5 or less.
Moreover, 0.01 or more is preferable.

The Tg of the copolymer (D) is -50 ° C. from the viewpoint of improving the cohesive strength of the adhesive obtained by blending (D).
Or more, more preferably -40 ° C or more. In addition, the temperature is preferably 20 ° C or lower, more preferably 0 ° C or lower, from the viewpoint of softening the adhesive obtained by blending (D) and improving the adhesive strength at low temperatures. That is,
The Tg of (D) is preferably from -50 to 20C, more preferably from -40C to 0C.

The Mn of the copolymer (D) is preferably 500 or more, more preferably 1,000 or more, from the viewpoint of improving the cohesive strength and holding power of the adhesive. Further, from the viewpoint of improving the compatibility with the rubber (A) and improving the adhesive strength, it is preferably 10,000 or less, more preferably 50,000 or less.
00 or less. That is, Mn of (D) is 500 to
10,000 is preferable, and 1,000 is more preferable.
~ 5,000. The weight average molecular weight (Mw) of the copolymer (D) is preferably from 1,000 to 20,000.
0, more preferably 1,500 to 10,000.
That is, Mw of (D) is preferably 1,000 or more, more preferably 1,500 or more. Also 2
It is preferably at most 10,000, more preferably at most 10,000.
00 or less. Mw / Mn is preferably from 1.2 to 2.5, and more preferably from 1.3 to 2.0. That is,
Mw / Mn is preferably 1.2 or more, and more preferably 1.3 or more. Moreover, it is preferably 2.5 or less, more preferably 2.0 or less.

The solubility parameter (hereinafter referred to as SP value) of the copolymer (D) improves the compatibility with the rubber (A) and the plasticizer (C), improves the adhesive strength, and improves the plasticizer retention. From the viewpoint of improvement, 7.5 to 11.5 is preferable, 7.8 to 11.2 is more preferable, and 8.0 to 1 is particularly preferable.
1.0. That is, it is preferably at least 7.5, more preferably at least 7.8, particularly preferably at least 8.0. Moreover, it is preferably 11.5 or less, more preferably 11.2 or less, particularly preferably 11.0 or less. The SP value is a value obtained from the following equation. SP value (δ) = (ΔH / V) ^{1/2 where} ΔH represents molar heat of vaporization (cal) and V represents molar volume (cm ³ ). ΔH and V are expressed as “PO
LYMER ENGINEERING ANDFEBR
UARY, 1974, Vol. 14, No. 2, RO
BERT F. FEDORS. (Pp. 151-153) "
(ΔH) of the heat of vaporization of the atomic groups (△ e _i )
And the total volume (V) of the molar volume (△ v _i ) can be used.

As the (co) polymer (E), those comprising an aromatic ring-containing monomer as an essential constituent monomer can be used. As the aromatic ring-containing monomer, an aromatic vinyl monomer (d
1) can be used. As the aromatic vinyl monomer (d1) constituting the (co) polymer (E), the same ones as those described in (d1) of (D) can be used. Of these, preferred are styrene and α-methylstyrene, and particularly preferred is styrene.

As a monomer constituting the (co) polymer (E), another monomer (d5) can be copolymerized with the above (d1) if necessary. Specific examples of (d5) include (d2), (d3), and (d4). Of these, preferred are unsaturated carboxylic acids and (meth) alkyl having 1 to 24 carbon atoms in the alkyl group.
Acrylates and dialkyl esters of unsaturated dicarboxylic acids, aliphatic dienes having 4 to 12 carbon atoms and 5 carbon atoms
~ 14 alicyclic dienes, more preferably (meth)
Acrylic acid and alkyl (meth) acrylate (carbon number is 12 to 18).

When another monomer (d5) is used, the amount of (d5) constituting the (co) polymer (E) is preferably 0.01 from the viewpoint of the compatibility and cohesion of the hot melt adhesive. -10% by weight, more preferably 0.1-5%
% By weight.

(1) A monomer is continuously or intermittently supplied to a heated solvent in the presence of a polymerization initiator. After the polymerization, the solvent and, if necessary, unreacted monomers are distilled off under normal pressure or reduced pressure. A method for obtaining a copolymer (solution polymerization method). Solvents used for solution polymerization include aromatic hydrocarbons (toluene, xylene, cumene, etc.), aliphatic hydrocarbons (n
-Hexane, n-octane, n-decane, etc.), alicyclic hydrocarbons (cyclohexane, methylcyclohexane, etc.), halogen-containing systems (chloroform, carbon tetrachloride, dichloroethane, etc.), ketones (acetone, methyl ethyl leketone, etc.) , Ether (dioxane, dibenzyl ether), ester (ethyl acetate, isopropyl acetate,
Butyl acetate) and the like.

(2) A polymerization initiator is added to a solution prepared by dissolving a monomer alone or a copolymer obtained by pre-polymerization in a monomer, and the resulting mixture is heated and polymerized. A method of obtaining a copolymer by distillation under reduced pressure (bulk polymerization method).

(3) 1 selected from (A), (B), (C) and (E) which are constituents of the hot melt adhesive
In the presence of a polymerization initiator, a monomer is continuously or intermittently fed into a melt of one or more kinds or a solution obtained by adding the above-mentioned solvent to the melt to carry out polymerization. A method in which a reaction monomer is distilled off under normal pressure or reduced pressure to obtain a mixture comprising a copolymer and other components (coexistence polymerization method).

The polymerization temperature in the above radical polymerization is 80
The temperature is preferably in the range of -240 ° C, and can be suitably selected according to the type and amount of the polymerization initiator to be used and the intended molecular weight. The end point of the reaction can be confirmed by measuring the amount of unreacted monomer at the time of polymerization using gas chromatography. The temperature at which the solvent or unreacted monomer is distilled off varies depending on the type of the monomer.
~ 200 ° C is preferred. Among the radical polymerization methods of the copolymer (D), the coexistence polymerization method is preferred from the viewpoint of compatibility.

The (co) polymer (E) can be obtained by polymerizing the above constituent monomers by a known method such as radical polymerization, thermal polymerization, or cationic polymerization in the same manner as in the production of (D). The production method is not particularly limited,
For example, the following thermal polymerization method can be exemplified.

(1) A method in which monomers are continuously or intermittently supplied into a heated solvent, and after the polymerization is completed, the solvent and, if necessary, unreacted monomers are distilled off under normal pressure or reduced pressure to obtain a copolymer ( Solution polymerization method). As the solvent used for the solution polymerization, the same solvent as in the case of producing (D) can be used.

(2) After heating and polymerizing a solution of a monomer alone or a (co) polymer obtained by pre-polymerization in a monomer, unreacted monomer is distilled off under normal pressure or reduced pressure if necessary. (Bulk polymerization method).

The polymerization temperature in the above thermal polymerization is usually from 80 to
The range is 280 ° C., and the end point of the reaction can be confirmed by measuring the amount of unreacted monomer at the time of polymerization using gas chromatography. The temperature at which the solvent or unreacted monomer is distilled off depends on the type of monomer,
Usually it is 100-250 ° C. Among the thermal polymerization methods for the (co) polymer (E), the solution polymerization method is preferred from the viewpoint of controlling the molecular weight.

As the (co) polymer (E), the above-mentioned (co) polymer containing an aromatic vinyl monomer (d1) as an essential constituent monomer
In addition to polymers, polycondensation polymers (polyamide, polyimide, polyester, polycarbonate, polyphenylene oxide, polysulfone, polyphenylene sulfide, polyether ketone, and modified products thereof) and polyaddition polymers (polyurethane, etc.) can also be used. Examples of the polyamide include polyphenylene adipamide and the like. Examples of the polyester include polyethylene terephthalate and polybutylene terephthalate. As polycarbonate, for example,
And polyoxycarbonyloxy-1,4-phenyleneisopropylidene-1,4-phenylene.

Examples of the polyphenylene oxide include poly-1,4-phenylene oxide and poly-phenylene oxide.
2,6-dimethyl-1,4-phenylene oxide and the like. Examples of the polysulfone include polyoxy-1,4-phenylenesulfonyl-1,4-phenylene. Examples of polyphenylene sulfide include polythio-1,4-phenylene and the like. Examples of the polyurethane include polyphenylene hexamethylene diurethane. Among these, polycondensation polymers are preferred, more preferably polyphenylene oxide, and particularly preferably poly-2,6.
-Dimethyl-1,4-phenylene oxide.

The Tg of the (co) polymer (E) is at least higher than the Tg of the copolymer (D) from the viewpoint of achieving both heat resistance and flexibility of the hot melt adhesive obtained by blending (E). It is preferably 10 ° C. higher, more preferably 15 ° C.
° C or higher, particularly preferably 20 ° C or higher, most preferably 4 ° C or higher.
0 ° C. or higher. Tg of (co) polymer (E)
Is preferably 25 ° C. or higher, more preferably 30 ° C. or higher, from the viewpoint of improving the cohesive strength of the adhesive obtained by blending (E). Further, from the viewpoint of improving the compatibility of the adhesive obtained by blending (E) and not increasing the melt viscosity of the hot melt adhesive of the present invention, 20
The temperature is preferably 0 ° C or lower, more preferably 180 ° C or lower. That is, the Tg of (E) is preferably from 25 to 200C, more preferably from 30 to 180C.

The Mn of the (co) polymer (E) is preferably 1,300 or more, more preferably 1,500 or more, from the viewpoint of improving the cohesive strength of the adhesive. Further, from the viewpoint of improving the compatibility with the rubber (A), 10,000
Or less, more preferably 5,000 or less. That is, 1,300 to 10,000 are preferable,
More preferably, it is 1,500 to 5,000. The Mw of the (co) polymer (E) is preferably 1,50.
0 to 20,000, more preferably 2,000 to 10,
000. That is, Mw of (E) is 1,500
Or more, more preferably 2,000 or more. Moreover, it is preferably 20,000 or less, more preferably 10,000 or less. Mw / Mn is 1.2 to 3.
0 is preferred, and more preferably 1.3 to 2.5. That is, Mw / Mn is preferably 1.2 or more,
More preferably, it is 1.3 or more. Moreover, it is preferably 3.0 or less, more preferably 2.5 or less.

The SP value of the (co) polymer (E) is preferably 8.4 to 12.0 from the viewpoint of improving the compatibility with the rubber (A) and the plasticizer (C) and improving the adhesive strength. , More preferably 8.5 to 11.8, particularly preferably 8.6 to
11.5. That is, the SP value of (E) is 8.4.
It is preferably at least 8.5, more preferably at least 8.5, particularly preferably at least 8.6. Further, it is preferably 12.0 or less, more preferably 11.8 or less, and particularly preferably 1 or less.
1.5 or less.

The content of the rubber (A) based on the total weight of (A), (B), (C), (D) and (E) in the hot melt adhesive of the present invention is determined from the viewpoint of improving cohesive strength. It is preferably at least 5% by weight, more preferably at least 10% by weight, particularly preferably at least 12% by weight, based on the weight of (A) to (E). From the viewpoint of melt viscosity, the content is preferably 40% by weight or less, and more preferably 30% by weight or less.
% By weight or less, particularly preferably 28% by weight or less. That is, the content of (A) is preferably 5 to 40% by weight,
More preferably, it is 10 to 30% by weight, particularly preferably 12 to 28% by weight.

Tackifying resin (B) based on the total weight
The content of (A) is from the viewpoint of improving the adhesive strength.
10% by weight or more based on the weight of (E) is preferable,
More preferably 20% by weight or more, particularly preferably 25% by weight.
% By weight or more. Also, from the viewpoint of improving flexibility,
It is preferably at most 60% by weight, more preferably at most 50% by weight, particularly preferably at most 45% by weight. That is, the content of (B) is preferably from 10 to 60% by weight, more preferably from 20 to 50% by weight, and particularly preferably from 25 to 45% by weight.

From the viewpoint of melt viscosity, the content of (C) based on the total weight is based on the weight of (A) to (E).
It is preferably at least 1% by weight, more preferably at least 5% by weight, particularly preferably at least 8% by weight. In addition, from the viewpoint of improving cohesion, the content is preferably 30% by weight or less, more preferably 25% by weight or less, and particularly preferably 22% by weight or less. That is, the content of (C) is preferably 1 to 30% by weight, more preferably 5 to 25% by weight, and particularly preferably 8 to 22% by weight.

The content of (D) based on the total weight is preferably 1% by weight or more, more preferably 5% by weight, based on the weight of (A) to (E), from the viewpoint of improving the compatibility of each component. % Or more, particularly preferably 10% by weight or more. In addition, from the viewpoint of improving the cohesive force, the content is preferably 40% by weight or less, more preferably 35% by weight or less, and particularly preferably 30% by weight or less. That is, the content of (D) is preferably 1 to 40% by weight, and more preferably 5 to 40% by weight.
It is preferably from 35 to 35% by weight, particularly preferably from 10 to 30% by weight.

The content of (E) based on the total weight is preferably 0.5% by weight or more, more preferably 1% by weight, based on the weight of (A) to (E), from the viewpoint of improving the resin strength.
% By weight or more, particularly preferably 2% by weight or more. In addition, from the viewpoint of improving flexibility, the content is preferably 30% by weight or less, more preferably 25% by weight or less, and particularly preferably 20% by weight or less. That is, the content of (E) is 0.5 to
It is preferably 30% by weight, more preferably 1 to 25% by weight, and particularly preferably 2 to 20% by weight.

The content ratio (D) / (E) of the copolymer (D) and the (co) polymer (E) is 0% from the viewpoint of the compatibility and cohesion of each component in the hot melt adhesive. .1 or more, more preferably 0.5 or more. Moreover, it is preferably 30 or less, more preferably 10 or less. That is, (D) / (E) is preferably 0.1 to 30,
0.5 to 10.

The hot melt adhesive of the present invention can contain other additives (F) as required.
(F) includes an antioxidant {a hindered phenol compound [for example, pentaerythyl-tetrakis [3-
(3,5-di-t-butyl-4-hydroxyphenyl)
Propionate], octadecyl-3- (3,5-di-
t-butyl-4-hydroxyphenyl) propionate, etc.], phosphorus compounds [for example, tris (2,4-di-t
-Butylphenyl) phosphite, etc.], sulfur compounds [for example, pentaerythyl-tetrakis (3-laurylthiopropionate), dilauryl-3,3'-thiodipropionate, etc.], etc .; Triazole-based compound [for example, 2- (3,5-di-t
-Amyl-2-hydroxyphenyl) benzotriazole, 2- (5-methyl-2-hydroxyphenyl) benzotriazole, etc.]; light stabilizers; hindered amine compounds [for example, (bis-2,2,6,6- Adsorbents (eg, alumina, silica gel, molecular sieve, etc.); organic or inorganic fillers (eg, talc,
Mica, calcium carbonate, etc., titanium oxide, calcium oxide, etc.); pigments; dyes;

When other additives (F) are added, the amount of these additives is 0.0% based on the weight of the hot melt adhesive, that of the antioxidant, ultraviolet absorber and light stabilizer.
It is preferably 1 to 5% by weight, more preferably 0.1 to 3% by weight.
% By weight. In addition, in the adsorbent and the filler, 0.0%
It is preferably from 1 to 40% by weight, and more preferably from 0.1 to 40% by weight.
15% by weight. For pigments, dyes and fragrances,
The content is preferably 0.005 to 2% by weight, and more preferably 0.01 to 1% by weight.

The method for producing the hot melt adhesive of the present invention is not particularly limited. For example, a method in which (A), (B), (C), (D) and (E) are heat-melted and mixed; A method in which each component is heated and dissolved by adding toluene, xylene, etc., and uniformly mixed, and then the solvent is distilled off. The method which is industrially preferable is the following method. In addition, a heating and melting kneader can be used as the mixing device. Examples of the heat-melt kneader include, but are not particularly limited to, its form and shape. For example, a pressurized reactor with a stirrer, a mixer having a highly compressible screw or ribbon-shaped stirrer, a kneader, a uniaxial Or a multi-screw extruder, a mixer, etc. can be mentioned. The mixing temperature is usually from 80 to 200 ° C., and the mixing is preferably performed in an inert gas atmosphere such as a nitrogen gas in order to prevent resin deterioration.

The method of applying the hot melt adhesive of the present invention to an adherend includes, for example, (1) a method of melting and coating the adherend, and (2) a method of applying a hot melt adhesive film or the like. There is a method of melting after being interposed between the bodies. Examples of (1) include, but are not limited to, spiral coating, roll coating, slot coat coating, control seam coating, bead coating, and the like. The coating amount is 0.1 to 1 for surface coating.
00 g / m ² , more preferably 1 to 50 g
/ M ² (ie, preferably 0.1 g / m ² or more, more preferably 1 g / m ² or more, and 100 g / m ² or more).
m ² or less, more preferably 50 g / m ² or less. ), In line coating, preferably 0.005 to 1 g / m, more preferably 0.01 to 0.5 g / m (that is, preferably 0.005 g / m or more, more preferably 0.01 g / m or more, Moreover, 1 g / m or less is preferable,
More preferably, it is 0.5 g / m or less. The thickness of the film (2) is preferably 1 to 500 μm, more preferably 5 to 300 μm (that is, preferably 1 μm or more, more preferably 5 μm or more, or 500 μm or more.
μm or less, more preferably 300 μm or less)
It is. The melting temperature when applied to an adherend is 80
~ 200 ° C is preferred, and the melt viscosity is 0.5-500Pa
S is preferable, and 1 to 100 Pa · s is more preferable.
(That is, preferably 0.5 Pa · s or more, more preferably 1 Pa · s or more, and preferably 500 Pa · s or less, and more preferably 100 Pa · s or less).

The hot melt adhesive of the present invention has an adhesive strength
It has excellent cohesion, flexibility and processability, so it can be applied to a wide range of adherends (for example, various plastic molded products, rubber, paper, cloth, metal, wood, glass, mortar concrete, etc.). It is suitable as a hot-melt adhesive for bonding certain polyolefin (polyethylene, polypropylene, etc.) resin molded articles or these and the above-mentioned other adherends. Examples of the bonding include polyolefins constituting disposable diapers. Adhesion between a nonwoven fabric and a polyolefin film. Examples of the adhesive body (third invention) in which polyolefin resin molded articles are bonded to each other or to another adherend with the hot melt adhesive of the present invention include disposable diapers, disposable sanitary napkins, adhesive tapes, and the like. An adhesive film and the like can be exemplified.

The adhesive of the present invention can be used not only in the form of a hot melt type but also in the form of an organic solvent solution, an emulsion, a dispersion, a film or the like. Also,
The hot melt adhesive of the present invention can also be used as a modifier for moldability and resin properties of various thermoplastic resins or thermosetting resins, a fluidity modifier for asphalt, and the like.

[0064]

EXAMPLES The present invention will be further described with reference to the following examples, but the present invention is not limited to these examples. In the following, “parts” indicates parts by weight. Production Example 1 1000 parts of xylene was charged into a stainless steel pressurized reactor, the atmosphere in the vessel was replaced with nitrogen, and the temperature was raised to 200 ° C. in a sealed state. At this temperature, 500 parts of styrene, 150 parts of dicyclopentadiene, 35 parts of 2-ethylhexyl acrylate
0 parts, paraffinic oil [Diana Process Oil P
W-90; manufactured by Idemitsu Kosan Co., Ltd.] 1000 parts and J-t
A mixed solution of 2.5 parts of -butyl peroxide was added dropwise over 4 hours, and further maintained at 180 ° C for 1 hour to complete the polymerization. The end point of the reaction was confirmed by disappearance of the monomer by gas chromatography. Then, xylene was distilled off (150 ° C., 2 kPa) from the produced polymer solution to obtain a copolymer (D-1). The Tg of the (D-1) is -20 ° C, M
n was 1,800 and SP value was 10.3.

Production Example 2 In Production Example 1, styrene 500
Parts, 150 parts of dicyclopentadiene and 350 parts of 2-ethylhexyl acrylate,
A copolymer (D-2) was obtained in the same manner as in Production Example 1 except that 00 parts and 300 parts of stearyl methacrylate were used.
Tg of the (D-2) is -30C, Mn is 1,600, S
The P value was 10.1.

Production Example 3 In Production Example 1, styrene 500
Parts, 150 parts of dicyclopentadiene and 350 parts of 2-ethylhexyl acrylate,
A copolymer (D-3) was obtained in the same manner as in Production Example 1, except that 00 parts, 290 parts of stearyl methacrylate, and 10 parts of methacrylic acid were used. The Tg of (D-3) is -35 ° C,
Mn was 2,400 and SP value was 10.2.

Production Example 4 700 parts of dibenzyl ether was charged into a stainless steel pressurized reactor, and the inside of the vessel was purged with nitrogen.
Temperature. At this temperature, 1000 parts of styrene was added dropwise over 4 hours, and further kept at 240 ° C. for 3 hours to complete the polymerization. The end point of the reaction was confirmed by disappearance of the monomer by gas chromatography. Then, dibenzyl ether was distilled off from the produced polymer solution (230 ° C., 1.3 k
Pa) to obtain a copolymer (E-1). Tg of (E-1) was 40 ° C., Mn was 1,800, and SP value was 10.5.

Production Example 5 In Production Example 1, styrene 500
Part, dicyclopentadiene 150 parts and 2-ethylhexyl acrylate 350 parts, instead of styrene 9
A copolymer (E-3) was obtained in the same manner as in Production Example 1 except that 50 parts and 50 parts of stearyl methacrylate were used. Tg of the (E-3) was 35 ° C., Mn was 2,500, and SP value was 10.4.

Examples 1 to 10 and Comparative Examples 1 to 5 A mixture of each component mixed according to the formulation (parts by weight) shown in Table 1 was charged into a stainless steel pressurized reactor, and the inside of the vessel was purged with nitrogen. The temperature was raised to 160 ° C. in a closed state, and the mixture was melt-mixed with stirring for 4 hours to obtain a hot melt adhesive of the present invention and a comparative hot melt adhesive.

[0070]

[Table 1] (Explanation of Symbols, etc.) A-1: Styrene-butadiene block copolymer rubber "Clayton D-1155" [manufactured by Clayton Polymer Japan Ltd.] Styrene content 40% by weight; MI = 14 A-2: Hydrogenated styrene-isoprene Block copolymer rubber “Septon 2043” [manufactured by Kuraray Co., Ltd.] Styrene content 13% by weight; MI = 5 A-3: Hydrogenated styrene-isoprene block copolymer rubber “Septon 2002” [manufactured by Kuraray Co., Ltd.] Styrene content 30% by weight; MI = 45 B-1: Partially hydrogenated petroleum resin (C9 fraction copolymer main component)
“Alcon M-115” [manufactured by Arakawa Chemical Co., Ltd.]; softening point =
115 ° C B-2: Hydrogenated petroleum resin (main component of DCPD copolymer)
"ESCOLETS ECR-229F" [manufactured by Tonex Corporation]; softening point = 137 ° C C-1: naphthenic oil "Diana Process Oil N"
P-24 "[manufactured by Idemitsu Kosan Co., Ltd.] C-2: Paraffin oil" Diana Process Oil PW-90 "[manufactured by Idemitsu Kosan Co., Ltd.] E-2: Polyphenylene oxide (poly-2,6-dimethyl-) 1,4-phenylene oxide)
Noril PPO SA120, manufactured by Nippon GE Plastics Co., Ltd., Mw 6350, SP value 11.2, Tg16
0 ° C. F-1: Hindered phenolic antioxidant “Irganox 1010” [manufactured by Ciba Specialty Chemicals Co., Ltd.] F-2: Phosphorus antioxidant “ADK STAB 2112”
[Asahi Denka Kogyo Co., Ltd.] F-3: Benzotriazole UV absorber "Tinuvin 328" [Ciba Specialty Chemicals Co., Ltd.]
Made

Performance Test Examples Each of the hot melt adhesives obtained in Examples 1 to 10 and Comparative Examples 1 to 5 was subjected to JIS K6301-1995.
Hardness by hardness test, tensile strength by JIS K6301-1995 tensile test, and BL by the above test method
The melt viscosity at 140 ° C. was measured with a mold viscometer.
Examples 1 to 10 and Comparative Examples 1 and 2 having these physical properties
For each of the hot melt adhesives of No. 5, the T-type peeling adhesive strength, the texture of the bonded body, the coatability, and the odor at the time of melting were evaluated (test methods are shown below). The results are shown in Table 2. . As is clear from the results in Table 2, the hot melt adhesive of the present invention has a remarkable balance between the texture of the adhesive, the coating properties, the T-peel adhesive strength, and the odor at the time of melting, as compared with those of the comparative examples. It turns out that it is excellent.

[0072]

[Table 2]

Test Method (Hand of Adhesive) A film of a hot-melt adhesive having a thickness of 20 μm is sandwiched between nonwoven fabrics made of polypropylene and having a thickness of 100 μm, and the feel is evaluated by touch. (Coatability) A hot melt adhesive is applied to the nonwoven fabric under the following conditions, and the spiral coatability is checked. Conditions Applicator used; MC-112 (manufactured by Nordson) Gunhead; Spiral spray gun (manufactured by Nordson) Nozzle: 18/1000 inch wide nozzle (manufactured by Nordson) Coating temperature; 130 ° C line Speed: 100 m / min Coating width: 20 mm Coating amount: 5 g / m ² Evaluation criteria A: Coating is possible without any disturbance in the coating pattern. ：: Coating is possible although the coating pattern is disordered. ×: Stable coating was not possible. (T-type peel adhesive strength) Each hot melt adhesive has a length of 10
Coated in a bead shape with a width of 25 mm on a polypropylene non-woven fabric having a size of 0 mm x 25 mm x 100 m thick (application temperature 150
° C, an application amount of 0.06 g / m), and a polypropylene nonwoven fabric of the same size was laminated. After standing for 24 hours in an atmosphere of 25 ° C, a tensile tester (Autograph AGS-50)
Peel strength was measured at a tensile speed of 300 mm / min using OB (manufactured by Shimadzu Corporation), and the maximum value was defined as T-type peel adhesive strength (unit: g / 25 mm). (Odor at the time of melting) A hot-melt adhesive sample (30 g) was placed in a 200-ml glass bottle, and an aluminum lid was put on the bottle.
Leave for 60 minutes in a 50 ° C circulating air dryer. Remove the bottle, immediately remove the aluminum lid, smell the odor, and evaluate the odor intensity organoleptically. Table 3 shows the evaluation criteria.

[0074]

[Table 3]

[0075]

The hot melt adhesive of the present invention has the following effects as compared with the conventional one. (1) Since the hot melt adhesive is soft, the texture of the bonded body is excellent, and the cohesive strength and the adhesiveness are good, so that the hot melt adhesive has excellent adhesive strength to various adherends. In particular, the adhesive strength to a poorly adhesive material such as a polyolefin material is extremely good. Furthermore, since the melt viscosity is low and low-temperature coating is possible, it is possible to apply directly to an adherend such as a polyethylene film having low heat resistance. (2) Since the heat loss of the hot melt adhesive is low, generation of mist during melting is suppressed, and generation of odor is extremely small. Because of the above effects, the hot melt adhesive of the present invention is extremely useful as a hot melt adhesive or pressure-sensitive adhesive for various plastics, especially for polyolefin resin molded articles.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4J040 BA182 BA202 CA031 CA051 CA052 CA071 CA081 CA101 CA102 DA022 DA041 DA141 DB041 DB051 DB061 DB071 DB081 DB101 DK012 DM011 DN032 DN072 EB032 HB02 JB01 KA26 KA31 LA01 LA02 LA06

Claims (9)

[Claims] (1) a hardness at 23 ° C. of 4 to 20,
A hot melt adhesive having a tensile strength of 0.8 to 5 MPa and a melt viscosity at 140 ° C. of 1,000 to 6,000 mPa · s. 2. A diene (co) polymer and ethylene-α.
In a hot melt adhesive comprising one or more rubbers (A) selected from olefin copolymers, a tackifier resin (B) and a plasticizer (C), the hardness at 23 ° C. is 4 to 20, and the tensile strength is Is 0.8 to 5 MPa,
And the melt viscosity at 140 ° C. is 1,000 to 6,000.
A hot melt adhesive having a pressure of 0 mPa · s. 3. The heat loss after heating for 3 hours in an air atmosphere at 150 ° C. is 0.01 to 2% by weight.
The hot melt adhesive as described. 4. A diene (co) polymer and ethylene-α.
One or more rubbers (A) selected from olefin copolymers, tackifier resins (B), plasticizers (C), aromatic vinyl monomers (d1) and aliphatic or cycloaliphatic compounds having 4 to 20 carbon atoms. Copolymer (D) containing saturated hydrocarbon (d2) and / or alkyl or alkenyl (meth) acrylate (d3) having 4 to 24 carbon atoms in the alkyl or alkenyl group as a constituent monomer, and (D) 4. The hot melt according to claim 2, comprising a (co) polymer (E) having a glass transition temperature at least 10 ° C. higher than the glass transition temperature (Tg) and having an aromatic ring-containing monomer as an essential constituent monomer. adhesive. 5. The composition according to claim 5, wherein (A) is 5 to 40% by weight and (B) is 10 to 60% by weight based on the total weight of (A), (B), (C), (D) and (E). 5. The hot melt adhesive according to claim 4, comprising 1 to 30% by weight of (C), 1 to 40% by weight of (D), and 0.5 to 30% by weight of (E). 6. The hot melt adhesive according to claim 2, wherein (A) is a styrene-butadiene block copolymer and / or a styrene-isoprene block copolymer and / or a hydrogenated product thereof. 7. The glass transition temperature of (D) is -50 to 20.
C, the number average molecular weight is 500 to 10,000, and the solubility parameter is 7.5 to 11.5.
The hot melt adhesive according to any one of the above. 8. The number average molecular weight of (E) is from 1,300 to 1,
The hot melt adhesive according to any one of claims 4 to 7, wherein the adhesive has a glass transition temperature of 25 to 200 ° C and a solubility parameter of 8.4 to 12.0. 9. An adhesive formed by bonding polyolefin resin molded articles to each other or to another adherend with the hot melt adhesive according to any one of claims 1 to 8.