JPH10183091A - Two-component chloroprene rubber latex adhesive composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an adhesive compsn. which has a stickiness retention power, is excellent in adhesiveness just after used for bonding, exhibits the increase in strength with time, and has a good heat resistance by combining a major component comprising a latex of a chloroprene rubber contg. no gel and an emulsion of a tackifying resin with a curative. SOLUTION: This compsn. is obtd. by combining a major component with a polyisocyanate compd. as the curative. The major component comprises a chloroprene rubber latex of which G given by the formula: G(%)=(w0 /w1 )×100 [wherein G is the chloroform-insolubles content; w1 is the wt. (g) of a film formed by casting the latex: and w0 is the dry wt. of insolubles remaining on 200 mesh metal net when a 5% chloroform soln. of the film is filtered with the net] is 0 and an emulsion of a tackifying resin which satisfies the relation: 0.6>=w1 /T>=0.2 [wherein w1 is the amt. (pts.wt) of the resin based on 100 pts.wt. chloroprene rubber; and T is the softening point ( deg.C) of the resin].

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a two-part chloroprene rubber latex adhesive composition. More specifically, by combining a latex of chloroprene rubber containing no gel component, a main agent composed of a tackifying resin emulsion, and a curing agent composed of a polyisocyanate compound, the adhesion immediately after lamination is maintained while sufficiently maintaining the adhesive holding force. The present invention relates to a two-part adhesive composition having excellent heat resistance, improved strength over time, and good heat resistance.

[0002]

2. Description of the Related Art In a method of using a solvent-based chloroprene rubber adhesive, a two-part adhesive composition using a polyisocyanate compound as a curing agent is a well-known technique.
In particular, it is widely used mainly as an adhesive for shoes, since it has excellent initial adhesive strength and heat resistance, and its strength is improved over time.

On the other hand, water-based adhesives have been actively developed due to environmental pollution due to the use of organic solvents and health problems of workers, and are gradually shifting to solvent-free adhesives. Against this background, chloroprene rubber latex is a type using an alkali metal rosin acid salt soap, which is generally used as an emulsifying and dispersing agent, and Japanese Patent Publication No. 52-1398.
No. 3, JP-B-61-29968 and the like, a latex for an adhesive using a water-soluble polymer such as polyvinyl alcohol as an emulsifying / dispersing agent is provided.

[0004]

However, the chloroprene rubber latex produced by these methods has the following problems.

(1) Regardless of whether an alkali metal rosin acid salt or a water-soluble polymer such as polyvinyl alcohol is used as an emulsifier / dispersant, the conventional latex contains a gel component of chloroprene rubber. High adhesive properties cannot be obtained. For example, when an adhesive is applied to an adherend and then bonded after drying, sufficient initial strength is not obtained, and no improvement in strength over time is observed. This is because, due to the presence of the gel component, the interdiffusion of the adhesive at the bonding interface at the time of bonding and after bonding becomes insufficient, resulting in inferior tackiness. Especially,
When a curing agent is used in combination, no mutual diffusion can be expected.

(2) When an emulsifier having good latex stability in a high pH range, such as an alkali metal rosin acid salt, is produced using an emulsifier, tackification, which is an essential auxiliary component of a chloroprene-based adhesive, is provided. Since rubber precipitates due to slight fluctuations in pH when compounding resins, metal oxides, etc., the pH must be adjusted very carefully.
Operationally cumbersome.

(3) When manufactured using a water-soluble polymer such as polyvinyl alcohol, the latex exhibits excellent stability due to its protective colloid property, but has a water-resistant property when used as an adhesive. Is significantly reduced.

The present invention has been made in view of the above problems, and has as its object to provide adhesive properties such as room temperature adhesive strength, high temperature adhesive strength, and water resistance, which cannot be obtained with conventional chloroprene rubber latex adhesives. In particular, it is an object of the present invention to provide an adhesive composition having good latex stability, excellent adhesiveness immediately after lamination, excellent adhesiveness immediately after lamination, improved strength over time, and excellent heat resistance.

[0009]

Means for Solving the Problems Based on such background, the present inventors have conducted intensive studies to solve the above problems, and as a result, completed the present invention. That is, the present invention is, (a) the following equation (1) _{G (%) = (W 0} / W i) × 100 (1) ( wherein, G is chloroform-insoluble portion (%), W _i is a chloroprene rubber latex Is the weight (g) of the film formed by casting, and W ₀ is the dry weight (g) of the insoluble matter that cannot be filtered through a 200-mesh wire gauze after dissolving the film in chloroform to a concentration of 5%. Chloroprene rubber latex two-part adhesive composition comprising a chloroprene rubber latex in which G is 0, a main agent comprising (b) a tackifying resin emulsion, and a polyisocyanate compound as a curing agent. is there.

[0010] In particular, the tackifying resin is the following equation (2) _{0.6 ≧ W t /T≧0.2 (2)} ( wherein, W _t is the weight of the tackifier resin to the chloroprene rubber 100 parts by weight (solid Chloroprene rubber latex which satisfies the softening point (° C.) of the tackifying resin), can maximize the adhesive holding power, and is a polyisocyanate compound as a curing agent. By combining with the above, other adhesive properties can be sufficiently satisfied.

Hereinafter, the present invention will be described in detail.

Chloroprene rubber latex in [0012] The present invention has the following (1) _{G (%) = (W 0} / W i) × 100 (1) ( wherein, G is chloroform-insoluble portion (%), W _i chloroprene weight of the film formed by casting a rubber latex (g), W ₀ is the dry weight (g of this after the film is dissolved so that the concentration of 5% in chloroform, insoluble matter that can not be filtered through a 200-mesh metal gauze G shown in ()) is 0. Here, G = 0 means that the gel content of the chloroprene rubber in the latex is 0.
When G is not 0, the interdiffusion between the adhesive interfaces does not proceed well, the adhesive force as the adhesive becomes insufficient, and the adhesiveness, the room temperature peel strength, the heat resistance, the water resistance and the like are inferior. .

The method for polymerizing the latex of the present invention is not particularly limited, and a chloroprene monomer and, if necessary, other copolymerizable ethylenically unsaturated monomers may be subjected to radical emulsion polymerization. In the emulsion polymerization, water, a monomer, an emulsifying / dispersing agent, a polymerization initiator, a chain transfer agent, and the like may be emulsified according to a known method, and polymerization may be performed at a predetermined temperature. Each raw material may be added all at once, sequentially added, or dividedly added. Examples of copolymerizable ethylenically unsaturated monomers include, for example, carboxyl group-containing vinyl monomers such as acrylic acid and methacrylic acid, acrylates such as methyl acrylate and methyl methacrylate, butadiene, and 2,3- Diene monomers such as dichlorobutadiene and 1-chlorobutadiene, and monomers usually used for copolymerization of chloroprene such as ethylene, styrene and acrylonitrile are appropriately used in an amount of 20 parts by weight or less. In particular, as a copolymer component,
It is preferable to use a carboxyl group-containing vinyl monomer because the wettability with the adherend is improved.

The emulsifying / dispersing agent used in the polymerization is not particularly limited, and may be a carboxylic acid type, a sulfonic acid type,
Sulfuric acid ester type anionic emulsifiers, nonionic emulsifiers and the like are used, for example, alkali metal salts of disproportionated rosin acids, alkyl sulfonates, alkyl aryl sulfonates, alkyl sulfates, alkyl aryl sulfates, naphthalene sulfones Examples include condensates of sodium acid and formaldehyde, polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenols, sorbitan fatty acid esters, polyoxyethylene acyl esters, and the like. In particular, in the case of a copolymer of a chloroprene monomer and a carboxyl group-containing vinyl monomer, alkali metal salts and triethanolamine salts of alkyl diphenyl ether disulfonic acid, alkali metal salts of alkylbenzene sulfonic acid and triethanolamine salt Alkali metal sulfates, triethanolamine salts and the like are preferably used in emulsion polymerization under acidic conditions. The optimum range of the amount of the emulsifying / dispersing agent varies depending on the type of each emulsifying / dispersing agent. Is preferred.

Examples of the polymerization initiator include known free radical-generating substances, for example, peroxides such as potassium persulfate and ammonium persulfate, and inorganic or organic peroxides such as hydrogen peroxide and t-butyl hydroperoxide. Can be used. These may be used alone or in a redox system in combination with a reducing substance such as thiosulfate, thiosulfite, or organic amine.

The polymerization can be carried out at a temperature of from 0 to 80 ° C., preferably from 5 to 50 ° C.

Examples of the chain transfer agent include molecular weight regulators such as alkyl mercaptan, halogenated hydrocarbon, alkyl xanthogen disulfide and sulfur. The polymerization terminator is not particularly limited as long as it is a commonly used terminator. For example, phenothiazine, 2,6-t-butyl-4-methylphenol, hydroxylamine and the like can be used. The addition may be performed at the time when the conversion reaches a predetermined conversion. Polymerization conversion rate is 50 to 10
0% is preferable, and when residual monomers are present, monomer removal may be performed.

In order to further improve the latex stability of the chloroprene rubber latex of the present invention, a method of adding an emulsifying / dispersing agent in addition to the emulsifying / dispersing agent used in the emulsion polymerization is used. Examples of the timing of adding the emulsifying / dispersing agent include a method of adding all at the time of polymerization preparation, a method of adding during polymerization, and a method of adding at the end of polymerization, and are not particularly limited. % When it reaches%. The amount to be used is 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the charged monomer. Within this range, it is possible to satisfy the securing of latex stability and the maintenance of good water resistance when used as an adhesive. As the emulsifying / dispersing agent, alkali metal salts of rosin acid, sulfonic acid type, sulfate type anionic emulsifier, nonionic type emulsifier, for example, alkyl sulfonate, alkyl aryl sulfonate, alkyl sulfate, Alkylaryl sulfates, condensates of sodium naphthalene sulfonate and formaldehyde, polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenols,
Sorbitan fatty acid esters, polyoxyethylene acyl esters and the like can be mentioned.

The tackifier resin emulsion of the present invention is not particularly limited as long as it can be uniformly mixed with the chloroprene rubber latex of the present invention. Examples thereof include phenolic resins, terpene resins, rosin derivative resins, and petroleum hydrocarbons. Examples of the aqueous emulsion include resins such as hydrogenated rosin, pentaerythritol ester of hydrogenated rosin, polymerized rosin, rosin-modified resin containing rosin as a main component, alkyl phenol resin, rosin-modified phenol resin, terpene-modified phenol resin, and natural rosin. An aqueous emulsion such as a terpene resin is used. These resin emulsions are represented by the following formula (2): 0.6 ≧ W _t /T≧0.2 (2) (where W _t is the weight part of the tackifying resin with respect to 100 weight parts of chloroprene rubber (in terms of solid content) ), T is the softening point (° C.) of the tackifying resin. That is,
When the resin has a high softening point, a larger amount is used, and when the resin has a low softening point, a smaller amount is used. However, (2)
When the formula is less than 0.2, the interdiffusion of the adhesive interface is suppressed due to the effect of the curing reaction between the chloroprene rubber and the polyisocyanate compound, and a sufficient tackiness tends not to be maintained. On the other hand, if it exceeds 0.6, the curing of the chloroprene rubber and the polyisocyanate compound is inhibited due to the influence of a large amount of tackifier resin, and the adhesive properties become insufficient. As described above, the value within the range of the expression (2) is preferable because the adhesiveness can be sufficiently ensured and the adhesion performance can be further improved by crosslinking with the curing agent. The tackifier resin may be added by dissolving it in an organic solvent in advance, but is preferably added in the form of an emulsified emulsion.

The polyisocyanate compound as a curing agent in the present invention can be used as long as it is a compound which can be uniformly mixed with a blend of chloroprene rubber latex as a main component and a tackifier resin. preferable. For example, it can be manufactured by the following method. A method of forcibly dispersing a terminal isocyanate prepolymer in water using an emulsifier, a method of forcibly dispersing a polyisocyanate compound in which an isocyanate group is blocked in water using an emulsifier, a self-emulsifying polyisocyanate having a hydrophilic group in the molecule Method for producing compound, isocyanate group content of 10 obtained by reacting excess amount of aliphatic or aromatic polyisocyanate with polyether polyol
A method of forcibly dispersing about 30% by weight of a polyurethane prepolymer in water using an emulsifier, and a method of imparting hydrophilicity to the polyurethane prepolymer to form a self-emulsifying type. The amount of the polyisocyanate compound to be added is not particularly limited as long as the function as a curing agent can be exhibited, but the polyisocyanate compound is preferably 0.1 to 10 parts by weight based on 100 parts by weight of the chloroprene rubber polymer.

The two-part chloroprene rubber latex adhesive composition according to the present invention is as described above. The main component is a mixture of a chloroprene rubber latex containing no gel component and a tackifying resin emulsion in a predetermined ratio, and a polyisocyanate compound curing agent. The main agent and the curing agent are weighed and mixed just before the adhesive is used, and applied to the adherend.
Usually, it is dried at 40 to 90 ° C. for 5 to 10 minutes and bonded. If necessary, a thickener such as polyoxyethylene or polyvinyl alcohol, an antioxidant, a preservative, an antifreezing agent, a film-forming aid, a pH adjuster and the like may be added in appropriate amounts.

The adhesive composition of the present invention having the above constitution has good latex stability, adhesive properties such as room temperature adhesive strength, high temperature adhesive strength, and water resistance, which cannot be obtained with conventional latex adhesives. In particular, the adhesiveness is maintained, the adhesiveness immediately after lamination is excellent, the strength over time is improved, and the heat resistance is good.

[0023]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not limited to these examples.

The compounding stability, mechanical stability and room temperature peel strength, high temperature peel strength, heat creep test and water resistance of the latex obtained in the following Examples and Comparative Examples were measured and evaluated by the following methods. did.

<Mixing stability> The presence or absence of rubber precipitates caused by compounding with the latex for adhesive was visually observed.

；: No rubber deposition was observed. X: Precipitation of rubber was observed.

<Mechanical Stability> The mechanical stability of the main component of the adhesive composition was measured and evaluated as a rubber coagulation rate (%) using a Marlon test method.

<Normal temperature peel strength> SBR rubber plate (Showa Rubber, 150 mm × 25
mm) and No. 9 cotton canvas (150 mm × 25 mm) each with an adhesive composition of about 625 g / m.
^{After 2} (wet) coating, the coating was heated and dried at 60 ° C. for 10 minutes, and pressed with a hand roller. The specimen was cured in a constant temperature chamber at 23 ° C. for 1 hour and for 7 days.
The 180 ° peel strength of the test piece was measured at 23 ° C. and a tensile speed of 200 mm / min using a Tensilon type tensile tester.

<High-Temperature Peeling Strength> A test piece prepared in the same manner as in the measurement of the normal-temperature peeling strength was used.
The 180 ° peel strength was measured using a Tensilon type tensile tester under the condition of mm / min.

<Heat resistance creep test> SBR (Showa Rubber, 150 × 25 mm) surface finished with No. 60 polishing cloth
After applying 625 g / m ² of the adhesive composition to one side of the film by a brush, it was dried by heating at 60 ° C. for 10 minutes, and the hatched portion was covered with a polyethylene sheet as shown in FIG. As shown in (2), the hatched portion was cut off and pressed with a hand roller so that the bonded portion became 25 × 25 mm. The test piece was prepared by curing at 23 ° C. for 3 days in a constant temperature room. One end of the test piece is hung into a thermostat so as to perform 180 ° peeling, and a 200 g weight is attached so as not to give an impact to the other end, and the temperature in the thermostat is maintained at 80 ° C. The adhesive softened and could not withstand the load of the weight, and the time (minute) when the weight dropped was measured, and the heat creep test was performed. The last time is 60 minutes, and when it does not fall, it is indicated by "60 minutes or more". In addition, when the sheet did not drop but did shift, the length (mm) of the shift after 60 minutes was measured.

<Water Resistance> A test piece prepared in the same manner as in the measurement of peel strength at room temperature was immersed in pure water at 23 ° C. for 3 days, and excess water was immediately wiped off at 23 ° C. and a pulling speed of 200 mm.
/ Min using a Tensilon type tensile tester at 18
The 0 ° peel strength was measured.

Example 1 100 parts by weight of chloroprene, 0.15 part by weight of n-dodecylmercaptan, sodium alkyldiphenyletherdisulfonate (Perex SSH (trademark), manufactured by Kao)
3.5 parts by weight, 0.5 part by weight of a condensate of sodium naphthalenesulfonate and formaldehyde (Demol N (trademark), manufactured by Kao), 0.01 part by weight of sodium hydrosulfite, 0.2 part by weight of triethanolamine And 100 parts by weight of pure water were charged to a 10-liter autoclave equipped with a stirrer at 80% volume, at 40 ° C. in a nitrogen atmosphere, and 0.35 parts by weight.
A weight percent aqueous solution of potassium persulfate was continuously added dropwise. Conversion rate of 98%, 2,6-t-butyl-4- as a polymerization terminator
To the mixture was added 0.05 parts by weight of methylphenol to obtain a chloroprene rubber polymer latex A (solid content: 50% by weight).
The properties of the obtained latex were G = 0 (gel content,
Chloroform-insoluble part G (%) = (W ₀ / W _i ) × 100,
A sample latex is cast to form a film, the weight of the sample (W _i (g)) is measured, and the sample is put into a volumetric flask together with chloroform so as to have a concentration of 5%, and immersed at 23 ° C. for one day. Then, it is filtered through a 200 mesh wire mesh,
After washing with chloroform, the residue is dried at 110 ° C. and the weight (W ₀ (g)) is measured. ) And a solution viscosity of 2100
mPa · s (viscosity of a solution obtained by dissolving a chloroprene polymer in chloroform to a concentration of 10%. B-type viscometer (No. 3 rotor, 12 rpm, 25 ° C., 60 seconds)
c. ) Measurement. )Met.

The obtained polymer latex A and a tackifier resin emulsion (rosin ester resin, superester E-720, softening point 100 ° C., solid content 50% by weight, manufactured by Arakawa Chemical) were mixed at a ratio of 100 to 40 (solid content, (Weight ratio).

The self-emulsifying polyisocyanate compound (C
R-60N, 100 parts by weight of Dainippon Ink and Chemicals) and 100 parts by weight of pure water were uniformly mixed using a homomixer to obtain an emulsified dispersion as a curing agent. The two-component adhesive composition was obtained by stirring and mixing the curing agent with the main agent at a weight ratio of 100: 7 (in terms of solid content).

Table 1 shows the evaluation results of the blending stability and mechanical stability of the prepared base material, as well as the normal temperature peel strength, high temperature peel strength, heat creep and water resistance of the adhesive composition.

From the results shown in Table 1, the stability, the normal temperature peel strength,
It was found that high temperature peel strength, heat creep, and water resistance were excellent. Regarding the room temperature peel strength, the strength immediately after lamination was good and a sufficient improvement in strength was recognized after 7 days.

[0037]

[Table 1]

Example 2 100 parts by weight of Aquanate AQ-100 (manufactured by Nippon Polyurethane Industry), which is a self-emulsifying polyisocyanate compound, and 100 parts by weight of pure water were uniformly mixed using a homomixer, and emulsified as a curing agent. A dispersion was obtained. The two-component adhesive composition was prepared by stirring and mixing the curing agent with the base material of Example 1 at a weight ratio of 100: 5 (in terms of solid content).

Table 1 shows the evaluation results of the formulation stability, mechanical stability, and room temperature peel strength, high temperature peel strength, heat creep, and water resistance of the adhesive composition.

From the results shown in Table 1, the stability, the normal temperature peel strength,
It was found that high temperature peel strength, heat creep, and water resistance were excellent. Regarding the room temperature peel strength, the strength immediately after lamination was good and a sufficient improvement in strength was recognized after 7 days.

Example 3 The tackifier resin emulsion of Example 1 was used as a Harrier Star D
It was changed to S-70E (rosin ester resin, softening point 70 ° C, solid content 50% by weight, manufactured by Harima Chemicals). Latex A and tackifier resin emulsion were mixed at a ratio of 100 to 20 (solid content, weight ratio) to obtain a main ingredient. As the curing agent, the CR-60N emulsified dispersion used in Example 1 was used. The two-component adhesive composition was obtained by stirring and mixing the curing agent with the main agent at a weight ratio of 100: 5 (in terms of solid content).

Table 1 shows the evaluation results of the formulation stability, mechanical stability, and normal-temperature peel strength, high-temperature peel strength, heat creep, and water resistance of the adhesive composition.

From the results in Table 1, the stability, the peel strength at room temperature,
It was found that high temperature peel strength, heat creep, and water resistance were excellent. Regarding the room temperature peel strength, the strength immediately after lamination was good and a sufficient improvement in strength was recognized after 7 days.

Example 4 97 parts by weight of chloroprene, 3 parts by weight of methacrylic acid, n-
0.75 parts by weight of dodecyl mercaptan, sodium alkyldiphenyl ether disulfonate (Perex SS
H (trademark), manufactured by Kao) 5 parts by weight, sodium hydrosulfite 0.01 part by weight, triethanolamine 0.1 part by weight.
80 parts by volume of 2 parts by weight and 105 parts by weight of pure water were charged into a 10-liter autoclave equipped with a stirrer, and a 0.35% by weight aqueous solution of potassium persulfate was continuously added dropwise at 10 ° C. in a nitrogen atmosphere. 2,6-t- as a polymerization terminator at a conversion of 98%
By adding 0.05 parts by weight of butyl-4-methylphenol, chloroprene rubber polymer latex B was obtained. The properties of the obtained latex were measured in the same manner as in Example 1,
G = 0 and the solution viscosity was 2500 mPa · s.

The obtained polymer latex B and superester E-720, which is the tackifying resin emulsion used in Example 1, were mixed in a ratio of 100 to 40 (solid content, weight ratio).
To obtain a base material. As the curing agent, the aquanate AQ-100 emulsified dispersion used in Example 2 was used. The two-component adhesive composition was obtained by stirring and mixing the curing agent with the main agent at a weight ratio of 100: 7 (in terms of solid content).

Table 1 shows the evaluation results of the formulation stability, mechanical stability, and room temperature peel strength, high temperature peel strength, heat creep, and water resistance of the adhesive composition.

From the results shown in Table 1, the stability, the normal temperature peel strength,
It was found that high temperature peel strength, heat creep, and water resistance were excellent. Regarding the room temperature peel strength, the strength immediately after lamination was good and a sufficient improvement in strength was recognized after 7 days.

Example 5 In Example 4, the main component was obtained with the mixing ratio of the copolymer latex B and the superester E-720 as a tackifier resin emulsion being 100: 15 (in terms of solid content, weight ratio). AQUANATE AQ-100 which is a curing agent as a main ingredient
The emulsified dispersion was stirred and mixed at a weight ratio of 100 to 7 (in terms of solid content) to obtain a two-part adhesive composition.

Table 1 shows the evaluation results of the blending stability and mechanical stability of the prepared base material, and the evaluation of the adhesive composition at normal temperature peel strength, high temperature peel strength, heat creep and water resistance.

As shown in Table 1, the stability was good.
Although the peel strength at normal temperature, the peel strength at high temperature, the heat creep, and the water resistance were inferior to those in Example 4, practical values were shown.

Example 6 In Example 4, the main component was obtained with the mixing ratio of the copolymer latex B and the superester E-720 as a tackifier resin emulsion being 100: 70 (weight ratio in terms of solid content). AQUANATE AQ-100 which is a curing agent as a main ingredient
The emulsified dispersion was stirred and mixed at a weight ratio of 100 to 7 (in terms of solid content) to obtain a two-part adhesive composition.

Table 1 shows the evaluation results of the formulation stability, mechanical stability and room temperature peel strength, high temperature peel strength, heat creep and water resistance of the adhesive composition.

From the results shown in Table 1, the stability was good.
Although the peel strength at normal temperature, the peel strength at high temperature, the heat creep, and the water resistance were inferior to those in Example 4, practical values were shown.

COMPARATIVE EXAMPLE 1 In Example 4, an adhesion test was conducted using only a main component consisting of a copolymer latex B and a superester E-720 as a tackifier resin emulsion in a mixing ratio of 100 to 40 (solid content, weight ratio). Was done.

Table 1 shows the evaluation results of the formulation stability, mechanical stability, and normal temperature peel strength, high temperature peel strength, heat creep, and water resistance of the adhesive composition.

From the results shown in Table 1, the peel strength at normal temperature and water resistance were good, but the peel strength at high temperature and heat creep were very poor.

Comparative Example 2 In Example 4, the copolymer latex B was used as a main component without adding a tackifier resin emulsion. AQUANATE AQ-100 emulsified dispersion, which is a curing agent, is
The mixture was stirred and mixed at a weight ratio of 7 to 7 (in terms of solid content) to obtain a two-part adhesive composition.

Table 1 shows the evaluation results of the formulation stability, mechanical stability, and normal temperature peel strength, high temperature peel strength, heat creep, and water resistance of the adhesive composition.

From the results shown in Table 1, the heat-resistant creep was good, but the normal-temperature peel strength, the high-temperature peel strength, and the water resistance were very poor.

Comparative Example 3 97 parts by weight of chloroprene, 3 parts by weight of methacrylic acid, n-
0.2 parts by weight of dodecyl mercaptan, sodium alkyldiphenyl ether disulfonate (Perex SSH
(Trademark, manufactured by Kao) 5 parts by weight, sodium hydrosulfite 0.01 part by weight, triethanolamine 0.2
Parts by weight and 105 parts by weight of pure water were charged in a 10 l autoclave with a stirrer to 80% by volume, at 10 ° C. in a nitrogen atmosphere,
A 0.35% by weight aqueous solution of potassium persulfate was continuously added dropwise. At a conversion of 98%, chloroprene rubber polymer latex C was obtained by adding 0.05 parts by weight of 2,6-t-butyl-4-methylphenol as a polymerization terminator. The properties of the obtained latex were measured in the same manner as in Example 1, and G =
70 and a solution viscosity of 4150 mPa · s.

The obtained polymer latex C and superester E-720, which is the tackifying resin emulsion used in Example 1, were mixed in a ratio of 100 to 40 (solid content, weight ratio).
To obtain a base material. The curing agent is Aquanate AQ-1
A 00 emulsified dispersion was used. The two-component adhesive composition was obtained by stirring and mixing the curing agent with the main agent at a weight ratio of 100: 7 (in terms of solid content).

Table 1 shows the evaluation results of the formulation stability, mechanical stability, and room temperature peel strength, high temperature peel strength, heat creep, and water resistance of the adhesive composition.

From the results shown in Table 1, the stability was good.
However, room temperature peel strength, high temperature peel strength, heat creep, and water resistance were poor.

[0064]

As described above, the two-part chloroprene rubber latex adhesive composition obtained according to the present invention has adhesive properties such as room temperature adhesive strength, high temperature adhesive strength, and water resistance which are not available in the conventional latex. And latex stability is good, especially, because it is an adhesive composition that maintains adhesive holding power, has excellent adhesiveness immediately after lamination, has improved strength over time, and has good heat resistance, It is suitable as an adhesive for various uses such as leather, cloth, rubber, plastic, and metal.

[Brief description of the drawings]

FIG. 1 is a test piece of styrene-butadiene rubber used for a heat creep test.

FIG. 2 is a test piece of styrene-butadiene rubber used for a heat creep test.

Claims (5)

[Claims] 1. A (a) the following equation (1) _{G (%) = (W 0} / W i) × 100 (1) ( wherein, G is chloroform-insoluble portion (%), W _i is a chloroprene rubber latex The weight (g) of the film formed by casting, W ₀ is the dry weight (g) of the insoluble matter which cannot be filtered through a 200-mesh wire net after dissolving the film in chloroform to a concentration of 5%. A) a chloroprene rubber latex two-part adhesive composition comprising: a main component comprising a chloroprene rubber latex wherein G is 0, (b) a tackifier resin emulsion, and a polyisocyanate compound as a curing agent. 2. The two-part chloroprene rubber latex adhesive composition according to claim 1, wherein the chloroprene rubber latex is a latex obtained by using an emulsifying / dispersing agent for imparting latex stability. 3. The two-pack type chloroprene rubber latex adhesive composition according to claim 1, wherein the emulsifying / dispersing agent for imparting latex stability is a water-soluble salt of alkyl diphenyl ether disulfonic acid. Stuff. 4. A tackifier resin is the following equation (2) _{0.6 ≧ W t /T≧0.2 (2)} ( wherein, W _t is the weight of the tackifier resin to the chloroprene rubber 100 parts by weight (solid The chloroprene rubber latex two-pack type according to any one of claims 1 to 3, wherein the base agent satisfies the softening point (° C) of the tackifying resin. Adhesive composition. 5. The chloroprene according to claim 1, wherein the tackifier resin is selected from a phenolic resin, a terpene resin, a rosin derivative resin and a petroleum hydrocarbon resin. Rubber latex two-part adhesive composition.