JP3296865B2 - Reactive hot melt adhesive composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moisture-curable reactive hot melt adhesive composition. More specifically, the present invention relates to a reactive hot melt adhesive composition comprising a graft copolymer having an isocyanate group known as a moisture-curable reactive group, a specific low molecular weight polymer compatible with the graft copolymer, and a wax. More specifically, it is a non-adhesive solid before moisture curing, has low viscosity and excellent coatability, can be primarily fixed by low-temperature and short-time hot-press bonding at less than 100 ° C, and has a heat-resistant cohesive force due to a moisture curing reaction over time. Transition to a good adhesive,
It mainly relates to an acrylic reactive hot melt adhesive composition and also to a sandwich panel manufactured using the adhesive.

[0002]

2. Description of the Related Art Conventionally, a hot-melt type and a reactive type have been known mainly in the field of adhesive compositions. Hot-melt adhesive composition is a composition that has hot-melt applicator, heated and melted, coated and cooled and solidified to obtain instantaneous adhesive strength. As is well known, on the other hand, the adhesive strength at a high temperature is extremely low, and there is a limit to the adhesive reliability particularly in an environment generally at 80 ° C. or higher. Examples of the hot melt adhesive composition include JP-A-49-25033, JP-A-51-90342, and JP-B-58-17514.
No., JP-A-58-67772, and JP-A-58-67772
147473, JP-A-59-68385, JP-A-57-158276, JP-A-60-284.
No. 76 "and the like, and are generally ethylene-vinyl acetate-based, polyolefin-based (represented by low-density polyethylene-based and atactic polypropylene-based), and the like.
Compositions of block polymer type (SIS, SBS, SEBS type, etc.), butyl rubber type, polyester type, polyamide type and the like are known. The hot melt adhesive composition is used for binding, packaging, textile, furniture,
At present, it is widely used in the industries of woodworking, weak electricity, transportation, etc., but the range of use for each application is limited due to the limit of its heat-resistant adhesive strength, and it is recognized in the industry as a non-structural adhesive . Especially in the field of product assembly,
There is a demand for an adhesive composition having high heat resistance in the form of utilizing the initial adhesive strength of hot melt as it is, and it cannot be used with conventional hot melt compositions due to a remarkable decrease in adhesive strength at high temperatures. . On the other hand, the reactive adhesive composition can be expected to have high temperature rigidity and adhesive strength, and is used as a structural adhesive. However, reactive adhesive compositions such as epoxy, urethane, and acrylic, which are generally well known, have extremely poor initial adhesiveness, and promote a long-term curing reaction while holding down with a pressing jig to increase practical adhesive strength. Things are mandatory. That is, the reactive adhesive composition generally has a long curing time, which is a problem.

For these reasons, various reactive hot-melt adhesive compositions having both the properties such as the initial adhesive property of the hot-melt type and the properties of the heat-resistant adhesive strength of the reactive type have been studied in recent years. JP-B-47-518, JP-A-49-98445, JP-A-51-30898
The reactive hot-melt adhesive composition described in No. 1 discloses a composition comprising one kind of urethane prepolymer specified as an ethylene-vinyl acetate resin and a tackifying resin. JP-A-52-37936, JP-A-52-123436, and JP-A-56-45954.
The reactive hot-melt adhesive composition described in No. 1 is a polyethylene-based, polyester-based, ethylene-vinyl acetate resin-based, one kind of urethane prepolymer identified as any one of ethylene-ethyl acrylate-based resins. A product comprising a tackifying resin is disclosed. Also, a reactive hot-melt adhesive composition described in JP-A-63-120785 discloses a technique comprising a styrene-based block copolymer-based thermoplastic resin component and a specified urethane polyol. I have. In this case, the styrene-based block copolymer-based thermoplastic resin component provides the initial adhesiveness, the toughness effect of the styrene-based block copolymer, and the unsaturated hydrocarbon-based polyol represented by polybutadiene polyol and polyisoprene polyol; It is a disclosed technology that a cured product of a urethane prepolymer comprising a mixture of oxybutylene glycol satisfies heat resistance and elasticity. Such a reactive hot-melt adhesive composition is disclosed technology in which initial adhesive strength is exhibited by a thermoplastic resin as a base polymer, and high-temperature rigidity is exhibited by a urethane reaction over time. Overall, the initial adhesion and heat resistance of the composition are still insufficient.

The reactive hot-melt adhesive compositions described in JP-A-62-181375 and JP-A-64-1287 disclose a technology comprising a room temperature solid or crystalline polyurethane prepolymer. But
These have the disadvantage that the initial adhesiveness and the change in melt viscosity during coating are large. In addition, Japanese Patent Application Laid-Open No. 54-1497
No. 41, No. 55-160074 and No. 55-16973 disclose a technique comprising an olefin resin obtained by graft-polymerizing a silane compound. ing. Further, JP-A-59-172573 and JP-A-59-17573
4673 "describes a reactive hot-melt adhesive composition containing an alkoxysilyl group-containing polyester, and JP-A-59-174675 describes a reactive hot-melt adhesive composition containing an alkoxysilyl group. Although a technique comprising a polyamide having the same is disclosed, the balance between the initial adhesiveness and the heat resistance after moisture curing is insufficient. As described above, there is no moisture-curable reactive hot-melt adhesive composition that sufficiently satisfies the needs of the market, and has excellent initial adhesiveness and heat resistance with short-time adhesion, and a melt viscosity during coating. At present, there is a strong demand for a reactive hot-melt adhesive composition with little change. As for the technology of the acrylic adhesive, several attempts have been made mainly to hot-melt the acrylic pressure-sensitive adhesive. For example, JP-A-58-125774 and JP-A-56-1614
Acrylic hot-melt type pressure-sensitive adhesives described in JP-A-84-134 and JP-A-1-315409 generally lack hot-melt coatability or cohesive strength of the pressure-sensitive adhesive. JP-A-59-75975 discloses an alkyl (meth) acrylate having an average number of carbon atoms of an alkyl group of about 4 to 12, a weight average molecular weight of about 2000 or more, and a glass of about 20 ° C. or more. There is a description of an adhesive pressure-sensitive adhesive produced by copolymerizing a polymeric monomer having a transition temperature, but this adhesive pressure-sensitive adhesive has reactivity due to moisture curing after bonding. However, since the heat resistance is poor, the present invention is essentially different from the present invention.

In order to improve the above-mentioned disadvantage, Japanese Patent Application Laid-Open No.
76879 ", JP-A-3-119082 and JP-A-3-220275 have been proposed. However, in order to improve the cohesive force of the pressure-sensitive adhesive, an active energy ray-curable hot melt pressure-sensitive adhesive has been proposed. When the post-crosslinking is performed by an electron beam, there are disadvantages such that special equipment is required for electron beam irradiation, and workability on site is extremely deteriorated. Furthermore,
The acrylic moisture-curable hot-melt pressure-sensitive adhesive composition described in Japanese Patent Application Laid-Open No. 3-2591984 is an alkyl (meth) acrylate, a macromonomer (polymeric monomer), and a (meth) acryl having a silyl group. It consists of an acid ester and an isocyanate compound. However, there is a problem in hot melt coatability before moisture curing, and in particular, there is a problem that toxic gas generated from an isocyanate compound at the time of high-temperature melting is greatly restricted in terms of work. Further, the acrylic moisture-curable hot melt adhesive composition described in JP-A-3-139584,
A pressure-sensitive hot-melt adhesive comprising an alkyl (meth) acrylate, a polymerizable polymer and an unsaturated isocyanate has been proposed, but has a drawback that the change in melt viscosity is large, and it is an initial adhesive system at room temperature. This is different from the present invention. In addition, in the above proposal, in order to reduce the melt viscosity, a styrene-based tackifying resin is added,
Since the compatibility between the tackifying resin and the (meth) acrylic acid alkyl ester moiety is poor, the problem is that the initial adhesion is poor. In addition, in order to improve the disadvantage that the change in melt viscosity is large, an acrylic moisture-curable hot melt adhesive comprising an alkyl (meth) acrylate, a polymerizable polymer, an unsaturated isocyanate, an organic tin compound and an organic phosphorus compound is used. Agent composition is disclosed in Japanese Unexamined Patent Publication No. 4-314
82 ", the addition of an organophosphorus compound to reduce the change in melt viscosity has the disadvantage of slowing the moisture cure rate. Further, Japanese Unexamined Patent Application Publication No.
In the case of using only the graft copolymer described in Japanese Patent Application Laid-Open No. 4-314 and Japanese Patent Application Laid-Open No. 4-31482, an appropriate melt viscosity (100,000 centipoise) at a relatively low temperature (about 120 ° C.) in order to achieve excellent hot melt coatability. In the following, the initial adhesiveness and the initial cohesion before moisture curing are insufficient. Thus, at present, at room temperature, it is initially non-adhesive (not pressure-sensitive),
Acrylic reactive hot-melt adhesive compositions having satisfactory weather resistance and sufficiently satisfying market requirements have not yet been found. Especially in the market, it is easy to position when bonding, it is a non-adhesive solid at room temperature, has a small change in melt viscosity at the time of coating, shows excellent hot melt coatability, and has a low temperature reactivation type short time・ Acrylic hot-melt adhesive composition with sufficient initial cohesive strength by heat-pressure bonding and excellent temporary adhesion and fixability is possible. It is the present situation.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to solve the conventional disadvantages of the reactive hot melt type adhesive composition,
Without impairing the initial adhesive strength which is a feature of hot melt at the time of hot melt coating with a known applicator, after coating and pressing, the hot melt is moisture-cured and can be used as a quasi-structural or structural adhesive, It is non-tacky at room temperature and easy to work with, such as positioning when bonding, and it is possible to perform sufficient initial bonding and fixing with low-temperature reactivation type short-time, hot-press bonding.
An object of the present invention is to provide a novel reactive hot-melt adhesive composition having excellent heat resistance after moisture curing.

[0007]

That is, the present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that the following resin compositions are good, and have achieved the present invention. That is, the present invention is as follows. [A] One or a mixture of two or more of the following (A) selected from graft copolymers having a number average molecular weight of 10,000 to 200,000
0 to 90% by weight, and the number average molecular weight of the following (B) is 500
One or two selected from low molecular weight polymers of
Mixed resin 10 consisting of 90 to 10% by weight of a mixture of more than one kind
A reactive hot melt adhesive composition further comprising 1 to 35 parts by weight of a wax (C) having a melting point of 50 to 150 ° C based on 0 parts by weight. (A) Graft copolymer 1) Monomer (d ) having a vinyl group and an isocyanate group in a molecule, and a vinyl group and a methacryloyl group at a molecular end
Or a macromonomer (f) having an acryloyl group and having a number average molecular weight of 2,000 or more and a glass transition temperature of 20 ° C. or more, and an alkyl (meth) acrylate (g) having an alkyl group having 1 to 12 carbon atoms. ) it produced and the copolymerizing, and, (meth) graft copolymer glass transition temperature of the acrylic acid alkyl ester moiety has an isocyanate group which is -75~10 ℃ (a _1). 2) In the presence of a styrene copolymer thermoplastic resin (m), a monomer (d ) having a vinyl group and an isocyanate group in the molecule and an alkyl (meth) acrylate (g) are copolymerized. And the (meth) acrylic acid alkyl ester moiety has a glass transition temperature of -75.
Graft copolymer having an isocyanate group is ~10 ℃ _(A 2). 3 ) A graft having an isocyanate group obtained by graft-polymerizing a monomer (d ) having a vinyl group and an isocyanate group in the molecule to a thermoplastic polymer (n) having a glass transition temperature of -75 to 10 ° C. Copolymer (A ₃ ). (B) Low molecular weight polymer 1) It is obtained by copolymerizing at least one monomer selected from vinyl acetate and alkyl (meth) acrylate (g), and has a glass transition temperature of -40 to 100 ° C. Low molecular weight polymer (B ₁ ). 2) A copolymer obtained by copolymerizing at least one monomer selected from vinyl acetate and alkyl (meth) acrylate (g) with a monomer (d ) having a vinyl group and an isocyanate group in the molecule. And the glass transition temperature is-
Low molecular weight polymer having an isocyanate group is _{40 ℃ ~100 ℃ (B 2)} . [ B] The graft copolymer (A ₁ ) is a monomer (d ) having a vinyl group and an isocyanate group in the molecule. 1-4
0% by weight, 2 to 50% by weight of macromonomer (f) and 97.9% by weight of alkyl (meth) acrylate (g)
The reactive hot-melt adhesive composition according to [1], which is obtained by copolymerizing 30% by weight . [C] the graft copolymer (A ₂₎ is the presence of the thermoplastic resin (m) 2 to 50 wt%, monomers having a vinyl group and an isocyanate group in the molecule (d) 0. 1-4
The reactive hot melt adhesive composition according to the above [1], which is obtained by copolymerizing 0% by weight and 97.9 to 30% by weight of an alkyl (meth) acrylate (g). Thing . [D] graft copolymer _{(A 3),} with respect to the thermoplastic polymer (n) 90 to 98 wt%, monomers having a vinyl group and an isocyanate group in the molecule (d) 2 to 10 wt% The reactive hot melt adhesive composition according to the above [1], which is obtained by graft polymerization of [E] the wax (C) is, carnauba wax, polyethylene wax, either the melting point selected from paraffin wax, characterized in that it uses the wax in the range of 60 to 85 ° C. [i] - [D] 2. The reactive hot melt adhesive composition according to item 1. [ F ] For bonding the reactive hot melt adhesive composition according to any one of [a] to [ e] to a paper honeycomb core and a metal plate and / or wood plywood and / or a plastic plate Sandwich panel used as. [B] to [ e] are preferred embodiments of the present invention, and [ f ] is a preferred application embodiment.

Hereinafter, the present invention will be described in more detail. The number average molecular weight of the isocyanate group-containing graft copolymer (A) used in the present invention is usually 10,000 to 20.
0000, preferably 10,000 to 150,000
0, more preferably 10,000-100,000. If the number average molecular weight is less than 10,000, the cohesive strength of the adhesive is insufficient, and the heat resistance after curing is insufficient. If it exceeds 200,000, the melt viscosity of the adhesive is too high. This is because coating properties are likely to be poor. Further, in the graft copolymer (A) having an isocyanate group, the glass transition temperature of the polymer main chain of the copolymer represented by the alkyl (meth) acrylate portion or the glass transition of the thermoplastic polymer (n). The temperature is usually -75 ° C to 10 ° C, preferably -70 ° C to -20 ° C,
More preferably Ru -70 ℃ ~-30 ℃ der. If the temperature is lower than −75 ° C., the initial cohesive strength of the adhesive is insufficient, and if the temperature exceeds 10 ° C., low-temperature heat reactivation during initial bonding and fixing becomes a problem.
Insufficient adhesive strength after curing. In the present invention, the glass transition temperature of the polymer main chain of the copolymer represented by the alkyl (meth) acrylate portion and the glass transition temperature of the thermoplastic polymer were measured by a differential scanning calorimeter (DSC).

The low molecular weight polymer (B) used in the present invention
Number average molecular weight is usually 500 to 8000, preferably 1000 to 8000, more preferably 1000 to 700.
0. When the number average molecular weight is less than 500, the cohesive strength of the adhesive is insufficient, and the heat resistance is insufficient. Also, 8
If it exceeds 000, the melt viscosity of the adhesive is too high, resulting in poor coatability. Further, the glass transition temperature of the low molecular weight polymer (B) used in the present invention is usually -40C to 100C.
° C, preferably -20 ° C to 100 ° C, more preferably-
20 ° C to 80 ° C. If the temperature is lower than −40 ° C., the heat-resistant cohesive strength of the adhesive is insufficient. If the temperature exceeds 100 ° C., the impact resistance at the time of initial bonding becomes a problem, and the low-temperature hot-pressure bonding reactivation becomes a problem. In the present invention, the blending ratio of the graft copolymer (A) having an isocyanate group (A) of 10 to 90% by weight and the low molecular weight polymer (B) of 90 to 10% by weight is good, and based on 100 parts by weight of the mixed resin. A reactive hot-melt adhesive composition is preferably added and blended with 1 to 35 parts by weight of a wax (C) having a melting point of 50 to 150 ° C. Graft copolymer (A): low molecular weight polymer (B) is 10-90: 90-10, preferably 20-90, by weight ratio.
80: 80-20, more preferably 30-70: 70-
30. If the amount of the graft copolymer (A) is less than 10% by weight, the cohesive force of the adhesive is insufficient.
Since the melt viscosity of the adhesive is too high, the coatability is poor.
Further, the graft copolymer (A) and the low molecular weight polymer (B)
If the amount of the wax (C) is less than 1 part by weight with respect to 100 parts by weight of the mixed resin, there is tackiness at room temperature, and the bonding workability such as positioning is poor at the time of bonding, and if it exceeds 35 parts by weight, the adhesive strength is insufficient. I do.

Next, the graft copolymer (A₁) ~ (A
₃ ) Will be described. Graft copolymer (A
₁) Has a vinyl group and an isocyanate group in the molecule.
Monomer (d)When, Macromonomers (f) and (me
(T) The alkyl acrylate (g) is usually dissolved in a solvent.
Is manufactured by copolymerization by solution polymerization in the presence of a polymerization initiator.
To. TheRaft copolymer (A₁% Of each component used in)
Has a vinyl group and an isocyanate group in the molecule
Monomer (d)WhenIt is 0.1-40% by weight, macro
As the monomer (f), 2 to 50% by weight and (meth)
(T) The alkyl acrylate (g) is 97.
It is preferably 9 to 30% by weight. Monomer (d)But
If the content is less than 0.1% by weight, the heat resistance of the adhesive after moisture curing is obtained.
Insufficient properties and more than 40% by weight, the cured adhesive
It becomes brittle and has poor adhesion. Also, macromonomer
When (f) is less than 2% by weight, the adhesive before moisture curing
If the cohesive force of the adhesive is insufficient and exceeds 50% by weight, the adhesive is brittle.
And poor adhesion.

[0011] grayed RAFT copolymer (A ₂₎ is a monomer having a vinyl group and an isocyanate group in the molecule (d), and (meth) usually acrylic acid alkyl ester (g), previously the thermoplastic resin It is produced by copolymerizing by solution polymerization in the presence of a polymerization initiator in a solution in which (m) is dissolved in a solvent .

[0012] ratio of the components used in the graft copolymer _{(A 2),} the by monomers having a vinyl group and an isocyanate group (d) and in the molecule, 0.1 to 40 wt%, ( the meth) acrylic acid alkyl ester (g), 97.9 to 30 wt%, the thermoplastic resin (m), it is preferred that 2 to 50 wt%. When the amount of the monomer (d ) is less than 0.1% by weight, the heat resistance of the adhesive after moisture curing is insufficient, and when it exceeds 40% by weight, the adhesive after curing becomes brittle and the adhesive strength is poor. It is. If the content of the thermoplastic resin (m) is less than 2% by weight, the cohesive strength of the adhesive before moisture curing is insufficient, and if it exceeds 50% by weight, the adhesive strength is poor .

The graft copolymer (A ₃ ) is a thermoplastic polymer (n) having a glass transition temperature of -75 to 10 ° C., alone or in a solution obtained by dissolving the same in a solvent. ) 90 to 98% by weight of the monomer (d ) having a vinyl group and an isocyanate group in the molecule in an amount of 2 to 10% by weight. When the amount of the monomer (d ) is less than 2% by weight, the heat resistance of the adhesive after moisture curing is insufficient, and when it exceeds 10% by weight, the adhesive after curing becomes brittle and the adhesive strength is poor. . Next, a description will be given preparation of low molecular weight weight body _{(B 1) ~ (B 2} ). The low molecular weight polymer (B ₁ ) is obtained by subjecting at least one monomer selected from the group consisting of vinyl acetate and alkyl (meth) acrylate (g) to a solvent, usually in the presence of a polymerization initiator in a solvent. It is produced by copolymerization in solution polymerization. The low molecular weight polymer (B ₂ ) comprises at least one monomer selected from vinyl acetate and alkyl (meth) acrylate (g) and a monomer having a vinyl group and an isocyanate group in the molecule ( d ) is usually produced by copolymerization in a solvent in the presence of a polymerization initiator by solution polymerization .

The proportion of each component used in the low molecular weight polymer (B ₂ ) is 99.9 as at least one monomer selected from vinyl acetate and alkyl (meth) acrylate (g). 50% by weight, and a monomer having a vinyl group and an isocyanate group (d) and in its molecule, it is preferred that 0.1 to 50 wt%. The reactive hot-melt adhesive composition of the present invention is generally prepared by subjecting the prepared graft copolymer (A) solution or its simple substance and the low molecular weight polymer (B) solution or its simple substance to moisture for a long time. A predetermined amount is collected so as not to be exposed, and the wax (C) is further added and mixed, and in the case of a solution, the solvent is removed. A hot melt adhesive composition can be produced.

Next, the raw materials used in the production of the graft copolymer (A) and the low molecular weight polymer (B) will be described. Examples of the monomer (d) having a vinyl group and an isocyanate group in the molecule include m-isopropenyl-α, α′-dimethylbenzyl isocyanate
p-isopropenyl-α, α′-dimethylbenzyl isocyanate, methacryloyl isocyanate, 2-methacryloyloxymethyl isocyanate, 2-methacryloyloxyethyl isocyanate, 2-methacryloyloxypropyl isocyanate, acryloyl isocyanate, acryloyloxymethyl isocyanate,
At least one selected from the group consisting of acryloyloxyethyl isocyanate and acryloyloxypropyl isocyanate is exemplified .

Examples of the macromonomer (f), generally polystyrene, copolymers of styrene and acrylonitrile, poly (t-butylstyrene), poly (alpha-methyl styrene), polyvinyl toluene or terminal methacryloyl groups of polymethylmethacrylate, Acryloyl group
Or synthesized by living anion termination method or chain transfer polymerization method in which to introduce a vinyl group. The living anion termination method is a terminating agent having a double bond with a living anion-polymerized monomer such as styrene, acrylonitrile, vinyltoluene, t-butylstyrene, α-methylstyrene or methyl methacrylate, and growing the living anion. The reaction is to synthesize a macromonomer. US Pat. No. 3,786,116 and US Pat.
No. 842,059, disclosed by Milkovich et al. A second method of termination is to introduce an alkylene oxide such as ethylene oxide into the living anion,
It is converted to an alkoxide ion and further protonated to obtain a hydroxy-terminated polymer. The vinyl group, the methacryloyl group is then reacted by reacting the hydroxy group with, for example, an isocyanate alkyl acrylate or methacrylate having from 1 to 4 carbon atoms in the alkyl group.
Alternatively , a macromonomer having an acryloyl group is synthesized.

In the chain transfer polymerization method, radical polymerization is carried out with a polymerization initiator such as 4,4-azobis-4-cyano-valeric acid in the presence of a chain transfer agent such as thioglycolic acid, and a carboxyl group is terminated at the polymer terminal. introducing a functional group such as groups, and the functional group for example, polymerizable vinyl groups by reacting with glycidyl methacrylate, methacrylonitrile
A macromonomer having an yl group or an acryloyl group can be synthesized. The macromonomer (f) used in the present invention has a glass transition temperature of 20 ° C.
It is desirable to have the above number average molecular weight, and a macromonomer having a glass transition temperature of less than 20 ° C. or a number average molecular weight of less than 2000 has insufficient cohesive strength of the adhesive before moisture curing. More preferably, the macromonomer of the present invention has a number average molecular weight of 50,000 or less. The reason is that if the number average molecular weight is too large, the melt viscosity of the adhesive is too high, resulting in poor coatability. The alkyl (meth) acrylate (g) used in the present invention includes methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, and (meth) acrylate.
Isopropyl acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, amyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, (meth) ) Isooctyl acrylate, 2- (meth) acrylic acid
Ethylhexyl, decyl (meth) acrylate, (meth)
There are one or more selected from lauryl acrylate and pentyl (meth) acrylate. As for the suitability for use ratio, the invention [A] is preferable, and the invention [B] is preferable.
To [ d ] are preferable and there is no particular limitation. More preferably, the graft copolymers (A ₁ ) to (A ₂ )
So that the glass transition temperature of the (meth) acrylic acid alkyl ester moiety is in the range of −70 to 10 ° C., or the glass transition temperature of the low molecular weight polymers (B ₁ ) to (B ₂ ) is −40.
One or more of the above-mentioned alkyl (meth) acrylates may be appropriately selected and used so as to be in the range of 100 to 100 ° C.

[0018]

Examples of the thermoplastic resin (m), styrene -
Isoprene-styrene block copolymer resin, styrene-
Butadiene-styrene block copolymer resin, styrene-
Ethylene - butylene - styrene block copolymer resin, a styrene - ethylene - propylene - styrene block copolymers such as styrene block copolymer resin, scan styrene -
(Meth) acrylic acid alkyl ester graft copolymer resin, styrene- (meth) acrylic acid alkyl ester-
Styrene copolymer vinyl acetate graft copolymer resins, and the like <br/>. The heat The thermoplastic polymer (n), a styrene - isoprene - styrene block copolymer resin, styrene - butadiene - styrene block copolymer resin, a styrene - ethylene - butylene - styrene block copolymer resin, a styrene - ethylene - propylene - styrene Styrene block copolymers such as block copolymer resins, ethylene-vinyl acetate copolymer resins, ethylene-ethyl acrylate copolymer resins, ethylene-butyl acrylate copolymer resins, ethylene-propylene copolymer resins, butyl rubber,
Examples include isoprene rubber, acrylic rubber, ethylene-butene copolymer resin, ethylene-propylene-diene copolymer resin, soft polyester and soft polyurethane rubber, and particularly preferably, styrene-isoprene-styrene block copolymer resin, styrene-butadiene. -Styrene block copolymer resin, styrene-ethylene-butylene-
Styrene block copolymers such as styrene block copolymer resins and styrene-ethylene-propylene-styrene block copolymer resins are exemplified.

Preferred polymerization initiators used for producing the graft copolymer (A) and the low molecular weight polymer (B) of the present invention include dicumyl peroxide, benzoyl peroxide and t-butyl peroxy. -2-ethylhexanoate, 1,1-bis (t-butylperoxy) cyclohexane, α, α'-azobisisobutyronitrile, acetyl peroxide, t-butylperoxypivalate, t-
Butyl hydroperoxide, cumene hydroperoxide, t-hexylperoxypivalate, 2,2'-azobis- (2,4-dimethylvaleronitrile), lauroyl peroxide, t-butylperoxyneohexanoate, Di-t-butyl oxide, azodicyclohexylcarbonitrile, dimethyl α, α-azodiisobutyrate,
Succinic peroxide, dicumene peroxide, dichlorobenzoyl peroxide and the like can be used. Preferred solvents used when producing the graft copolymer (A) and the low molecular weight polymer (B) of the present invention are ethyl acetate, butyl acetate, benzene, toluene, xylene, cyclohexane, methyl ethyl ketone, n-hexane, n-Heptane, mineral spirit, and other solvents such as Solvesso 100 and Solvesso 150 can be preferably used. When producing the graft copolymer (A) or the low molecular weight polymer (B) of the present invention, the content other than the above-mentioned components is preferably 30% by weight or less as long as the characteristics of the present invention are not impaired. Other monomers copolymerizable with the above components may be used as the copolymerization component.

Examples of such other monomers include organic acid group-containing monomers such as α, β-unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid and fumaric acid and anhydrides thereof, ) Hydroxyethyl acrylate, a monomer having a hydroxyl group such as hydroxypropyl (meth) acrylate, a monomer having a glycidyl group such as glycidyl (meth) acrylate,
Unsaturated carboxylic acid amides having an amide group such as (meth) acrylamide, N-methylol (meth) acrylamide, N-butoxymethyl (meth) acrylamide and diacetone (meth) acrylamide; vinylpyridine;
Monomers having an amino group such as dimethylaminoethyl (meth) acrylate and diethylaminoethyl (meth) acrylate, and phosphate groups such as acid phosphooxyethyl (meth) acrylate and acid phosphooxypropyl (meth) acrylate And the like. Also,
Vinyl acetate (excluding low molecular weight polymer (B)),
Monomers such as (meth) acrylonitrile can also be copolymerized. Further, monomers such as polyfunctional acrylates represented by triethylene glycol diacrylate and pentaerythritol triacrylate, polyfunctional methacrylates represented by ethylene glycol dimethacrylate and trimethylolpropane trimethacrylate, and divinylbenzene can also be copolymerized. . Melting point 50-15
The wax (C) at 0 ° C. includes the following waxes. The wax having a melting point in the range of preferably 60 to 120 ° C., particularly preferably 60 to 85 ° C. is used for the adhesive of the present invention. Good from low temperature heat reactivation pressing adhesiveness and initial non-adhesive suitability.

As the wax (C), paraffin wax, microcrystalline wax, polyethylene wax, polypropylene wax, Fischer-Tropsch wax (Sazol wax), carnauba wax, montan wax, ozokerite, whale wax, wood wax, perilla wax, beeswax. , There is. Particularly preferred are paraffin wax, polyethylene wax and carnauba wax. According to the present invention, it is preferable to add 1 to 35 parts by weight to 100 parts by weight of the mixed resin of the graft copolymer (A) and the low molecular weight polymer (B). The reactive hot-melt adhesive composition of the present invention is composed of each of the above-mentioned compositions, and the following reaction hardening accelerator is added and blended in the range of 0.005 to 1% by weight for the purpose of further improving the reactivity. Things are much better. As the reaction hardening accelerator, an organic tin compound and a tertiary amine are preferably used alone or in combination. In particular, it is particularly preferable that dibutyltin dilaurate is used as the organotin compound and 1,3-dimethylimidazolidinone is used as the tertiary amine, because the effect and odorlessness can be simultaneously satisfied.

The reactive hot-melt adhesive composition of the present invention comprises a conventionally known antioxidant (antioxidant) such as a phosphite or a hindered phenol, an ultraviolet absorber such as benzotriazole, Thixotropic agent ,
Interface modifier, such as Chi Taneto-based coupling agent, what, etc. no problem also be appropriate combination use and the like. In the reactive hot-melt adhesive composition of the present invention, a thermoplastic polymer, a tackifying resin, a plasticizer, a filler, and the like described below can be added and compounded as long as the characteristics are not impaired.
Examples of the thermoplastic polymer include ethylene-vinyl acetate copolymer resin, ethylene-ethyl acrylate copolymer resin, ethylene-methyl methacrylate copolymer resin, styrene-isoprene-styrene block copolymer resin, and styrene-butadiene-styrene block copolymer. Resin, styrene-ethylene-butylene-styrene block copolymer resin, styrene-ethylene-propylene-styrene block copolymer resin, styrene-alkyl (meth) acrylate graft copolymer resin, styrene-alkyl (meth) acrylate- Examples include a vinyl acetate graft copolymer resin and polyester. Examples of the tackifying resin include rosin and its derivatives hydrogenated rosin, polymerized rosin, (hydrogenated) polymerized rosin, rosin glycerin ester, (hydrogenated) rosin glycerin ester, rosin pentaerythritol ester, (hydrogenated) rosin pentane Erythritol ester, disproportionated rosin glycerin ester and disproportionated rosin pentaerythritol ester,
Terpene phenolic resin, (hydrogenated) terpene phenolic resin, ketone resin, petroleum resin (aliphatic, aromatic, their copolymerized and alicyclic, etc.) and their hydrogenated products, terpene resin, (water And terpene resins, coumarone-indene resins and xylene resins. Particularly preferred are rosin and its derivatives, terpene phenol resins, (hydrogenated) terpene phenol resins, petroleum resins and their hydrogenated products, and ketone resins. Is done.

Examples of the plasticizer include liquid polyisobutene, liquid polybutene, liquid (hydrogenated) polyisoprene,
Liquid (hydrogenated) polybutadiene, paraffinic oil, naphthenic oil, epoxy plasticizer, phosphate esters,
Representative examples include phthalic acid esters, aliphatic dibasic acid esters, and glycol esters. As fillers, zinc oxide powder, magnesium oxide powder, metal powder, silica powder (including colloidal silica powder), calcium carbonate powder, titanium oxide powder, talc powder, alumina powder, carbon black powder,
One or two or more kinds of dried fillers selected from the above are preferred. In particular, it has been found that the use of zinc oxide powder, calcium carbonate powder, titanium oxide powder, talc powder, carbon black powder, etc., is preferable because the weather resistance is greatly improved and the thermal stability of the system is high. However, when the filler is used in an amount exceeding 30% by weight, the system exhibits high thixotropy in terms of viscosity, resulting in a decrease in workability. Further, it is not preferable because there is an adverse effect such that the abrasion of the hot melt applicator is remarkably promoted.

In the reactive hot melt adhesive composition of the present invention, the storage and handling at room temperature may be in accordance with a known storage method for urethane prepolymer-based adhesives. For example, it may be a pail or a film-filled package having excellent moisture-proof storage stability. When a film is used, a method of sealing and storing the film in a metal case is generally used. The main application is not particularly limited as it is intended for a water-containing material or a water-vapor-permeable material, but it is preferable to apply the adhesive on both sides of a paper honeycomb material, and then apply a pre-coated steel plate or an aluminum plate. And a sandwich panel formed by bonding and pressing a metal plate, a plastic plate, a wooden plywood, and the like on both surfaces. Further, it can be preferably used also in the field of plastic cosmetic applications such as plywood and non-plywood. The reactive hot-melt adhesive composition of the present invention is basically characterized by having a non-stick solid property at room temperature, and in that sense, it can be said to be a reactivated hot-melt adhesive. Because it retains non-stick properties at room temperature,
When the reactive hot-melt adhesive composition of the present invention is applied to a large adherend and cooled, the surface can be formed with almost no finger tack, so that the other large or complicated adherend or the like can be formed. Can be adhered while correcting the position accurately and accurately. In addition, the adhesive layer can prevent contamination by contamination such as dust before the completion of the bonding step. It is characteristic that an adhesive workability that cannot be exhibited by an adhesive based adhesive is obtained. Regarding the application method of the reactive hot melt adhesive composition of the present invention, the following handling method is generally used. In other words, it is common practice to prevent contact with moisture before melting at the time of heating or subdividing work, etc.
It may be dissolved in a melting tank or the like having excellent airtightness in dry air or a nitrogen atmosphere, and then discharged from a dedicated nozzle. That is, at the time of the coating and dissolving operation, a commercially available known applicator provided with an environmental control mechanism and a temperature control function such that the reactive hot melt adhesive does not cure with moisture is not particularly limited.

[0026]

EXAMPLES The present invention will be specifically described below with reference to examples, but these descriptions do not particularly limit the present invention. In addition, the evaluation of the composition adjusted in each Example and the comparative example was performed as follows. In the examples, "%" and "part" mean "% by weight" and "part by weight", respectively. (Change in Melt Viscosity) Under a nitrogen atmosphere, the melt viscosity at 120 ° C. or 150 ° C. at the initial stage and after 24 hours was measured by a B-type rotational viscometer. (Number average molecular weight) It was measured by gel permeation chromatography (GPC) manufactured by JASCO Corporation using a tetrahydrofuran solvent. It is a number average molecular weight in terms of polystyrene. (Glass transition temperature; Tg measurement) The glass transition temperature was measured by a differential scanning calorimeter (DSC) manufactured by Seiko Instruments Inc. The heating rate is 1
It was 0 ° C./min. (Normal temperature non-adhesive) At room temperature (20 ° C), a finger touch test was performed.
Judgment was made based on the following criteria. ◎ Very good (no resistance to the finger when peeling off) ○ Good (no resistance to the finger when peeling off) △ Somewhat poor (Slightly strong resistance to the finger when peeling off) × defective ( (Strong resistance to finger when peeled off) (Preparation of adhesion test piece) After melting the reactive hot melt type adhesive composition at 120 ° C. or 150 ° C., the thickness is 0.3 m.
m, a width of 25 mm and a length of 100 mm on a steel plate (polyester-based service coat surface) with a thickness of 100
After hot-melt coating so as to have an adhesive wrap area of 25 × 12.5 mm, the mixture is once cooled to room temperature. Then, a thick canvas of the same size was combined with the hot-melt-coated steel sheet, and reactivated by a hot press set at a predetermined temperature (reactivation temperature of 60 to 100 ° C.) to obtain an adhesion test piece. (Adhesive force measurement conditions) After reactivation, leave at room temperature for 10 minutes,
The initial adhesive strength (T-peel strength) was measured at 20 ° C. After curing at 20 ° C. and a relative humidity of 60% for one week, T-peel strength at 20 ° C. and 80 ° C. was measured. Adhesion strength, using a universal tensile tester, peeling speed 10mm
/ Min.

Example 1 Kraton G-16 which is a styrene-ethylenebutylene-styrene block copolymer resin as a thermoplastic resin
10 parts of 57X (SEBS, manufactured by Shell Chemical Co.) are dissolved in 40 parts of toluene, and 2-ethylhexyl acrylate 6 is dissolved.
5 parts, methyl methacrylate 20 parts, m-isopropenyl-α, α'-dimethylbenzyl isocyanate (AC
C) (5 parts) and 0.2 parts of t-hexyl peroxypivalate as a polymerization initiator.
Polymerization was carried out for an hour to prepare a graft copolymer (A ₂ ) solution. The number average molecular weight of this graft copolymer is about 4900
0, the glass transition temperature was about -44 ° C. On the other hand, in 100 parts of toluene, 20 parts of isobutyl acrylate, 80 parts of ethyl methacrylate and 10 parts of benzoyl peroxide as a polymerization initiator were added in 100 parts of toluene.
Polymerization was performed at 00 ° C. for 5 hours to prepare a low molecular weight polymer (B ₁ ) solution. The number average molecular weight of this low molecular weight polymer is about 24
00, the glass transition temperature was about 25 ° C. The above graft copolymer solution and the above low molecular weight polymer solution are mixed so that the weight ratio of the graft copolymer / low molecular weight polymer becomes 80/20, and the total of the graft copolymer and the low molecular weight polymer is further reduced. For 100 parts by weight, 25 parts of paraffin wax having a melting point of 70 ° C. and 0.02 part of dibutyltin dilaurate as a reaction curing accelerator were added, mixed, and subjected to toluene removal to obtain an intended product. Table 1 shows the evaluation results.

Example 2 As a solvent, in 50 parts of ethyl acetate, 72 parts of n-butyl acrylate, 10 parts of methyl methacrylate, and polystyrene having a methacryloyl group at a terminal as a macromonomer (trade name: CHEMLINK 4500, molecular weight: 130)
00, SARTOMER) 15 parts, 2-methacryloyloxyethyl isocyanate (Showa Denko KK) 3
And α, α′-azobisisobutyronitrile as a polymerization initiator were added, and the mixture was polymerized at a reaction temperature of 70 ° C. for 5 hours to prepare a graft copolymer (A ₁ ) solution. The number average molecular weight of this graft copolymer was about 20,500, and the glass transition temperature of the alkyl (meth) acrylate portion was about -47 ° C. On the other hand, in 100 parts of ethyl acetate, 40 parts of n-butyl acrylate, 60 parts of methyl methacrylate, and 5 parts of benzoyl peroxide as a polymerization initiator were added, and polymerized at a reaction temperature of 100 ° C. for 5 hours. A low molecular weight polymer (B ₁ ) solution was prepared. The low molecular weight polymer had a number average molecular weight of about 4900 and a glass transition temperature of about 0 ° C. The above graft copolymer solution and the above low molecular weight polymer solution are mixed so that the weight ratio of the graft copolymer / low molecular weight polymer becomes 70/30, and further,
25 parts of paraffin wax having a melting point of 70 ° C. was added to and mixed with 100 parts of the total weight of the graft copolymer and the low-molecular-weight polymer, and the mixture was de-ethyl acetate to obtain the desired product. Table 1 shows the evaluation results.

Example 3 70 parts of 2-ethylhexyl acrylate, 5 parts of methyl methacrylate, and a styrene-acrylonitrile copolymer (trade name) having a methacryloyl group at the terminal as a macromonomer in 40 parts of toluene as a solvent AN-6,
15 parts of m-isopropenyl-α, α'-dimethylbenzyl isocyanate (manufactured by ACC) and 0.15 parts of t-hexylperoxypivalate as a polymerization initiator are added. Then, the mixture was polymerized at a reaction temperature of 80 ° C. for 5 hours to prepare a graft copolymer (A ₁ ) solution. The number average molecular weight of this graft copolymer was about 58,000, and the glass transition temperature was about -55 ° C. On the other hand, in 200 parts of toluene, in 200 parts of toluene, 40 parts of isobutyl acrylate, 50 parts of ethyl methacrylate, 5 parts of vinyl acetate, 5 parts of m-isopropenyl-α, α′-dimethylbenzyl isocyanate (manufactured by ACC), and polymerization. 10 parts of benzoyl peroxide was added as an initiator, and polymerization was carried out at a reaction temperature of 100 ° C. for 5 hours to prepare a low molecular weight polymer (B ₂ ) solution. The number average molecular weight of this low molecular weight polymer is about 1
500, the glass transition temperature was about -18 ° C. The above graft copolymer solution and the above low molecular weight polymer solution are mixed so that the weight ratio of the graft copolymer / low molecular weight polymer becomes 60/40, and the total of the graft copolymer and the low molecular weight polymer is further mixed. For 100 parts by weight, 5 parts of carnauba wax having a melting point of 82 ° C. and paraffin wax 10 having a melting point of 50 ° C.
Parts and 0.05 parts of dibutyltin dilaurate as a reaction hardening accelerator were added, mixed, and detoluened to obtain an intended product. Table 1 shows the evaluation results.

[0030]

[0031]

Example4  The graft copolymer (A) prepared in Example-1 ₂ )When
The low molecular weight polymer (B) prepared in Example-3_Two)
The weight ratio of ft copolymer / low molecular weight polymer is 30/70.
So that the graft copolymer and low molecular weight
Melting point: 61 ° C paraffin based on 100 parts of total weight
10 parts of wax, dibutyltin as reaction hardening accelerator
Purpose by adding and mixing 0.05 parts of dilaurate
I got something. Table 2 shows the evaluation results..

[0033]

Comparative Example 1 The procedure of Example 1 was repeated except that no m-isopropenyl-α, α'-dimethylbenzyl isocyanate and wax were used. Table 3 shows the evaluation results. Comparative Example 2 The procedure of Example 2 was repeated except that no macromonomer and wax were used. Table 3 shows the evaluation results. Comparative Example 3 As a solvent, dissolved in 40 parts of toluene, acrylic acid 2
-Ethylhexyl 74 parts, methyl methacrylate 10
Part, (styrene-acrylonitrile) copolymer having a methacryloyl group at a terminal as a macromonomer (trade name: AN-6, molecular weight: 6000, manufactured by Toa Gosei Chemical Co., Ltd.) 15
, 5 parts of m-isopropenyl-α, α'-dimethylbenzyl isocyanate (manufactured by ACC) and 0.15 part of t-hexylperoxypivalate as a polymerization initiator were added, and the mixture was polymerized at a reaction temperature of 80 ° C for 5 hours. Then, a graft copolymer (A ₁ ) solution was prepared. This graft copolymer has a number average molecular weight of about 58,000 and a glass transition temperature of about -55 ° C.
Met. On the other hand, as a solvent in 100 parts of toluene,
40 parts of isobutyl acrylate, 5 parts of ethyl methacrylate
5 parts, m-isopropenyl-α, α′-dimethylbenzyl isocyanate (manufactured by ACC), 5 parts, and benzoyl peroxide as a polymerization initiator, 0.5 part, were added, and polymerized at a reaction temperature of 100 ° C. for 5 hours. A molecular weight polymer solution was prepared. The number average molecular weight of this low molecular weight polymer is about 2000
0, the glass transition temperature was about 20 ° C. The above graft copolymer solution and the above low molecular weight polymer solution are mixed so that the weight ratio of the graft copolymer / low molecular weight polymer becomes 60/40, and the total of the graft copolymer and the low molecular weight polymer is further mixed. 10 parts of paraffin wax having a melting point of 61 ° C. and 0.1 part of dibutyltin dilaurate as a reaction accelerator were added to and mixed with 100 parts by weight, and the mixture was subjected to toluene removal to obtain an intended product. Table 3 shows the evaluation results.

Comparative Example 4 The procedure of Example 2 was repeated except that the low molecular weight polymer (B ₁ ) was not used. Table 3 shows the evaluation results. Comparative Example 5 Adjustment was carried out in the same manner as in Example 1 except that no thermoplastic resin was used. Table 3 shows the evaluation results .

[0036]

As is clear from the above evaluation results, the reactive hot-melt adhesive composition of the present invention is non-adhesive in a normal state, so that the position can be corrected before heating and pressing in the bonding step. In addition, adhesive workability not exhibited by the conventional moisture-curable acrylic resin-based hot melt adhesive was exhibited. 60-100 ° C
Short-term (instantaneous) heat-press bonding at a relatively low temperature is possible, and it has excellent initial adhesive cohesive strength, and achieves instant adhesive fixation, which is an essential requirement for hot melt adhesives, and has the property of moisture curing over time. It is clear that the adhesive retained and ultimately has high heat resistance. And the reactive hot-melt adhesive composition of the present invention is excellent in both hot-melt coatability / stability and heat-resistant cohesive strength of the adhesive. It can be used effectively as an adhesive for assembly.

[0037]

[Table 1]

[0038]

[Table 2]

[0039]

[Table 3]

──────────────────────────────────────────────────続 き Continuing from the front page (72) Kenichi Yashiro, Inventor 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Prefecture Inside of Mitsui Toatsu Chemicals Co., Ltd. (56) References JP-A-60-260668 (JP, A) JP-A-3-504986 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C09J 151 / 00 C09J 131/04 C09J 201/02

Claims (6)

(57) [Claims] 1. The following (A) has a number average molecular weight of 10 to 90% by weight of a mixture of one or two or more selected from graft copolymers having a number average molecular weight of from 100,000 to 200,000. For 100 parts by weight of a mixed resin composed of 90 to 10% by weight of a mixture of one or two or more kinds selected from low molecular weight polymers of 500 to 8000, a wax (C) having a melting point of 50 to 150 ° C is further added. A reactive hot melt adhesive composition containing 35 parts by weight. (A) Graft copolymer 1) Monomer (d ) having a vinyl group and an isocyanate group in a molecule, and a vinyl group and a methacryloyl group at a molecular end
Or a macromonomer (f) having an acryloyl group and having a number average molecular weight of 2,000 or more and a glass transition temperature of 20 ° C. or more, and an alkyl (meth) acrylate (g) having an alkyl group having 1 to 12 carbon atoms. ) it produced and the copolymerizing, and, (meth) graft copolymer glass transition temperature of the acrylic acid alkyl ester moiety has an isocyanate group which is -75~10 ℃ (a _1). 2) In the presence of a styrene copolymer thermoplastic resin (m), a monomer (d ) having a vinyl group and an isocyanate group in the molecule and an alkyl (meth) acrylate (g) are copolymerized. And the (meth) acrylic acid alkyl ester moiety has a glass transition temperature of -75.
Graft copolymer having an isocyanate group is ~10 ℃ _(A 2). 3 ) A graft having an isocyanate group obtained by graft-polymerizing a monomer (d ) having a vinyl group and an isocyanate group in the molecule to a thermoplastic polymer (n) having a glass transition temperature of -75 to 10 ° C. Copolymer (A ₃ ). (B) Low molecular weight polymer 1) It is obtained by copolymerizing at least one monomer selected from vinyl acetate and alkyl (meth) acrylate (g), and has a glass transition temperature of -40 to 100 ° C. Low molecular weight polymer (B ₁ ). 2) A copolymer obtained by copolymerizing at least one monomer selected from vinyl acetate and alkyl (meth) acrylate (g) with a monomer (d ) having a vinyl group and an isocyanate group in the molecule. And the glass transition temperature is-
Low molecular weight polymer having an isocyanate group is _{40 ℃ ~100 ℃ (B 2)} . 2. The graft copolymer (A ₁ ) is a monomer (d ) having a vinyl group and an isocyanate group in the molecule.
0 . 1 to 40% by weight, 2 to 50% by weight of macromonomer (f) and alkyl (meth) acrylate (g) 9
The reactive hot melt adhesive composition according to claim 1, wherein the composition is obtained by copolymerizing 7.9 to 30% by weight. 3. A graft copolymer (A ₂ ) comprising a monomer (d ) having a vinyl group and an isocyanate group in the molecule in the presence of 2 to 50% by weight of the thermoplastic resin (m).
The reactive hot melt mold according to claim 1, which is obtained by copolymerizing 1 to 40% by weight and 97.9 to 30% by weight of an alkyl (meth) acrylate (g). Adhesive composition. 4. A graft copolymer (A _3), with respect to the thermoplastic polymer (n) 90 to 98 wt%, monomers having a vinyl group and an isocyanate group in the molecule (d) 2 ~
The reactive hot-melt adhesive composition according to claim 1, which is obtained by graft-polymerizing 10% by weight. 5. The wax (C) is carnauba wax,
The reactive hot melt adhesive composition according to any one of claims 1 to 4 , wherein a wax having a melting point selected from polyethylene wax and paraffin wax in the range of 60 to 85 ° C is used. 6. A reactive hot-melt adhesive composition according to any one of claims 1 to 5 and the paper honeycomb core, as adhesive between the metal plate and / or wood plywood and / or plastic plate Sandwich panel to be used.