JPH093423A - Polychloroprene latex for adhesive, its production and adhesive composition used therefor - Google Patents

Abstract

PURPOSE: To obtain a polychloroprene latex for an adhesive excellent in latex stability and satisfying adhesion physical properties such as adhesion retainability, ordinary temperature adhesive force, high temperature adhesive force, heat resistance and water resistance, especially the ordinary temperature adhesive force, the adhesion retainability and the heat resistance. CONSTITUTION: This polychloroprene latex is produced by emulsion-polymerizing monomers comprising (A) 100 pts.wt. of chloroprene, (B) 1-100 pts.wt. of 2,3- dichlorobutadiene, and if necessary, further (C) a carboxyl group-containing vinylic monomer. When the polymer in the latex is dissolved in chloroform in a concentration of 5%, the solution does not contain insolubles. The emulsion polymerization is performed in the presence of 0.5-10 pts.wt. of an emulsifying and dispersing agent and 0.01-3.0 pts.wt. of a mol.wt.-controlling agent at 0-80 deg.C in a conversion of 60-100%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is a polychloroprene latex for adhesives, and the solution of the polymer in the latex dissolved in chloroform at a concentration of 5% does not contain an organic solvent insoluble portion (gel component). The present invention relates to an adhesive polychloroprene latex, a method for producing the same, and an adhesive composition using the same. More specifically, chloroprene,
2,3-dichlorobutadiene, which is a polymer containing no gel component obtained by further adding a carboxyl group-containing vinyl compound as necessary, and is a latex using an emulsifying / dispersing agent that imparts latex stability, TECHNICAL FIELD The present invention relates to a polychloroprene latex for adhesives having excellent stability, which can dramatically improve the adhesive physical properties, particularly heat resistance while sufficiently maintaining the tackiness after application of the adhesive, a method for producing the same, and an adhesive composition using the same. It is a thing.

[0002]

2. Description of the Related Art Chloroprene rubber is generally used as a raw material for adhesives because it has high crystallinity and high cohesive force. In various adhesive applications, compounding agents such as chloroprene rubber and phenol resin, zinc oxide, magnesium oxide, etc. are flammable with toluene, methyl ethyl ketone, etc.
It has been used by dissolving it in a volatile organic solvent.

However, due to restrictions on solvent emissions into the atmosphere and the setting of permissible concentrations from the viewpoint of occupational safety, the use of latex as a solvent has been actively developed, and gradually, although gradually, Chloroprene rubber latex is being introduced to the market.

For example, a method for producing a copolymer latex of chloroprene and a vinyl monomer having a carboxyl group such as acrylic acid or methacrylic acid is disclosed in JP-A-61-1.
It is known as No. 2710. Further, a method for producing a latex for an adhesive using a water-soluble polymer such as polyvinyl alcohol as an emulsifying / dispersing agent and an adhesive using the same are known from Japanese Patent Publication No. 52-13983. Further, JP-A-6-287360 describes that a copolymer latex of chloroprene and 2,3-dichlorobutadiene can be used as an adhesive.

[0005]

However, the use of the latex produced by these methods has the following problems. (1) In the conventional latex, when a polymer having a high molecular weight is used to impart heat resistance, a gel component is unavoidably formed, which is inferior in adhesiveness retention and room temperature strength. However, high molecular weight could not be realized and heat resistance was impaired.

(2) When the production is carried out using an emulsifier having good latex stability in a high pH range such as an alkali metal rosin acid salt, tackification, which is an essential subcomponent of a chloroprene adhesive, is imparted. The compounding stability such that the rubber is precipitated by a slight pH fluctuation when compounding agents, metal oxides and the like is poor, and the pH must be adjusted very carefully, which is troublesome in operation. In addition, when a water-soluble polymer such as polyvinyl alcohol is used for the production, the protective colloid property shows excellent latex stability, but the water resistance when used as an adhesive is significantly reduced. .

The present invention has been made in view of the above-mentioned problems, and its object is to provide excellent latex stability, which has not been obtained with conventional latex adhesives, and to retain tackiness, room temperature adhesive strength, and high temperature. Adhesive strength, heat resistance, adhesive physical properties such as water resistance, in particular, adhesive latex having properties satisfying contradictory physical properties such as room temperature adhesive strength, tackiness retention and heat resistance, a method for producing the same, and using the same An object is to provide an adhesive composition.

[0008]

The inventors of the present invention have completed the present invention as a result of earnest studies for solving the above problems based on such a background. That is, according to the present invention, the solution obtained by dissolving the polymer in the latex in chloroform at a concentration of 5% is chloroprene containing no organic solvent insoluble portion, 2,3-dichlorobutadiene, and further carboxyl as necessary. The present invention relates to a polychloroprene latex for adhesives containing a group-containing vinyl compound as a main component. By copolymerization of 2,3-dichlorobutadiene, a high molecular weight can be realized without containing a gel component, so that the adhesive strength at room temperature is excellent and the tackiness after application of the adhesive can be sufficiently maintained. Moreover, the heat resistance can be dramatically improved by having 2,3-dichlorobutadiene. Further, since an emulsifying / dispersing agent capable of imparting stability to the latex is used, a latex having excellent stability including compounding stability can be obtained. Further, in the case of a copolymer with a carboxyl group-containing vinyl monomer, a crosslinking reaction with zinc oxide, magnesium oxide or the like is exhibited, so that the adhesive properties can be further improved.

The present invention will be described in more detail below.

The polychloroprene latex for adhesives of the present invention is 2,3-based on 100 parts by weight of chloroprene.
A solution obtained by emulsion-polymerizing a monomer consisting of 1 to 100 parts by weight of dichlorobutadiene and dissolving the polymer in the obtained latex in chloroform to a concentration of 5% is an organic solution insoluble part (gel component). It does not include. A few
-Dichlorobutadiene is preferably used in the above range because it can satisfy the heat resistance of the adhesive property. If the amount is less than 1 part by weight, the high molecular weight is not realized, and the gel component is generated so as to obtain a high molecular weight product. On the other hand, when the amount exceeds 100 parts by weight, the rigidity of 2,3-dichlorobutadiene appears in the characteristics, the tackiness after application of the adhesive becomes poor, and the adhesive strength at room temperature also decreases.

The latex of the present invention comprises chloroprene 10
0 parts by weight, 1 to 100 parts by weight of 2,3-dichlorobutadiene and a vinyl monomer containing a carboxyl group are emulsion-polymerized,
The solution obtained by dissolving the polymer in the obtained latex in chloroform to a concentration of 5% may not contain an organic solution insoluble part. The copolymer with the carboxyl group-containing vinyl monomer is characterized in that it has excellent high-temperature adhesiveness and good adhesion to various adherends. The copolymerizable carboxyl group-containing vinyl monomer, for example, acrylic acid, methacrylic acid, fumaric acid,
Examples thereof include unsaturated fatty acids such as maleic acid and crotonic acid. The amount of the carboxyl group-containing vinyl monomer is not particularly limited with respect to 100 parts by weight of chloroprene, but is preferably in the range of 0.5 to 4 parts by weight for improving heat resistance.

In addition, within the scope not deviating from the object of the present invention,
In addition to the carboxyl group-containing vinyl monomer, another copolymerizable ethylenically unsaturated monomer may be added and emulsion polymerization may be performed. Other copolymerizable ethylenically unsaturated monomers include, for example, ethylene, methyl methacrylate, acrylonitrile, and 1-chlorobutadiene. To maintain heat resistance, chloroprene 100
The amount is preferably 20 parts by weight or less with respect to parts by weight.

The method for polymerizing the latex of the present invention is not particularly limited, and the chloroprene monomer, 2, 3
-Dichlorobutadiene, a carboxyl group-containing vinyl monomer, and other copolymerizable ethylenically unsaturated monomers, if necessary, may be radical emulsion polymerized.

Emulsion polymerization may be carried out at a predetermined temperature by emulsifying water, a monomer, an emulsifying / dispersing agent, a polymerization initiator, a chain transfer agent, etc. according to a known method. Each raw material may be added all at once, sequentially added, or dividedly added. 2,3-dichlorobutadiene can improve adhesive properties such as heat resistance by copolymerization, and the solution when the polymer in the latex is dissolved in chloroform to a concentration of 5% does not contain an organic solvent insoluble part. Since the high molecular weight product is obtained in the state, the tackiness after application of the adhesive can be sufficiently retained.

The emulsifying / dispersing agent imparting latex stability to be used for polymerization is not particularly limited, and carboxylic acid type, sulfonic acid type, sulfuric acid ester type anionic emulsifiers, nonionic emulsifiers, etc. are used. For example,
Alkali metal salt of disproportionated rosin acid, alkyl sulfonate having 8 to 20 carbon atoms, alkyl aryl sulfate, condensate of sodium naphthalene sulfonate and formaldehyde, polyoxyethylene alkyl ether, polyoxyethylene alkylphenol, sorbitan Examples thereof include fatty acid ester and polyoxyethylene acyl ester. In the case of a copolymer obtained by adding a chloroprene monomer, 2,3-dichlorobutadiene, and a carboxyl group-containing vinyl monomer, if necessary, an alkyl diphenyl ether disulphonic acid alkali metal salt and triethanolamine salt. , Dodecylbenzenesulfonic acid alkali metal salt and triethanolamine salt, lauryl sulfate alkali metal salt and triethanolamine salt, and the like are preferably used in emulsion polymerization under acidic conditions. Among these, since the stability during polymerization is good, the water-soluble salt of alkyldiphenyl ether disulphonic acid was adjusted to 0.
It is preferable to use 5 to 10 parts by weight, more preferably 3 to 6 parts.
It is preferable to use parts by weight.

As the polymerization initiator, known free radical-forming substances, for example, persulfates such as potassium persulfate and ammonium persulfate, inorganic or organic peroxides such as hydrogen peroxide and tert-butyl hydroperoxide, etc. 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 temperature is not particularly limited and may be 0.
It can be performed in the range of -80 ° C, preferably 10-5.
It is in the range of 0 ° C.

The time of termination of the polymerization is not particularly limited, but the polymerization is preferably carried out up to a monomer conversion of 60 to 100%, more preferably 95 to 100%.

Examples of chain transfer agents include alkylmercaptans, halogenated hydrocarbons, molecular weight regulators such as alkylxanthogen disulfide and sulfur. Of these, n-dodecylmercaptan is preferred from the viewpoint of odor and workability. Preferably, the amount used is 0.1-3.
0 parts by weight is preferable, and 0.3 to 1.0 parts by weight is more preferable.

The polymerization terminator is not particularly limited as long as it is a commonly used terminator and, for example, phenothiazine, 2,6-tert-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. The polymerization conversion rate is preferably 60 to 100%, and when residual monomers are present, monomer removal may be carried out.

In order to further improve the latex stability of the adhesive latex of the present invention, a method of adding an emulsifying / dispersing agent other than the emulsifying / dispersing agent used in emulsion polymerization is used. When to add an emulsifying / dispersing agent,
There is a method of adding all at the time of charging the polymerization, a method of adding during the polymerization and a method of adding at the end of the polymerization, but there is no particular limitation, but it is preferable to add at the time when the conversion rate reaches 50 to 90% during the polymerization. . The addition amount used is 1 to 10 parts by weight, preferably 3 to 5 parts by weight, based on 100 parts by weight of the charged monomers. Within this range, it is possible to satisfy the stability of latex stability and the maintenance of good water resistance when used as an adhesive. As the emulsifying / dispersing agent, an alkali metal salt of rosin acid, a sulfonic acid type, a sulfuric acid ester type anionic emulsifier, or a nonion type emulsifier is used. For example, an alkyl sulfonate having 8 to 20 carbon atoms or an alkyl aryl sulfate. , A condensate of sodium naphthalene sulfonate and formaldehyde, polyoxyethylene alkyl ether, polyoxyethylene alkylphenol, sorbitan fatty acid ester, polyoxyethylene acyl ester, etc., preferably an alkali metal salt of alkyldiphenyl ether disulphonic acid and triethanol. Amine salts, alkali metal salts and triethanolamine salts of dodecylbenzenesulfonic acid, alkali metal salts and triethanolamine salts of lauryl sulfate, etc. are used.

The method for producing the polychloroprene latex for adhesives has been described above. However, chloroprene monomer, 2,3-dichlorobutadiene and chloroprene monomer are necessary in view of easy control of polymerization and easy handling of the finished latex. Correspondingly, the total amount of monomers obtained by adding carboxyl group-containing vinyl monomer 1
An emulsion that imparts latex stability to 100 parts by weight.
Dispersant 0.5 to 10 parts by weight, molecular weight modifier 0.1 to 3.
Polymerization is carried out at 10 to 50 ° C. in the presence of 0 parts by weight, and a monomer obtained by polymerization up to a monomer conversion of 60 to 100% is preferable. On the other hand, in the presence of 3 to 6 parts by weight of an emulsifying / dispersing agent which imparts latex stability and 0.3 to 1.0 part by weight of a molecular weight modifier, polymerization is carried out at 10 to 50 ° C. to obtain a monomer conversion rate. The thing obtained by superposing | polymerizing to 95-100% is especially preferable.

The polychloroprene latex for adhesives in the present invention can be used alone or in combination. The latex for adhesives obtained by the present invention can be used alone as an adhesive, but the addition of a tackifier and a metal oxide (hydroxide) improves the adhesive physical properties.

The tackifier in the present invention is not particularly limited, and examples thereof include phenolic resins, terpene resins, rosin derivative resins, petroleum hydrocarbons, and the like. For example, hydrogenated rosin, hydrogenated rosin The pentaerythritol ester, polymerized rosin, rosin-modified resin containing rosin as a main component, alkylphenol resin, rosin-modified phenol resin, terpene-modified phenol resin, natural terpene resin and the like are used.

These resins are contained in an amount of 10 to 80 parts by weight, preferably 20 parts by weight, based on 100 parts by weight of the chloroprene rubber polymer.
~ 40 parts by weight are used. Within this range, sufficient tackiness can be secured and the adhesive performance can be further improved. As an addition method, it may be added by dissolving it in an organic solvent in advance, but it is preferably added in the form of an emulsion dispersed.

The metal oxide (hydroxide) in the present invention is an oxide (hydroxide) of a group II to group III metal cation, such as magnesium oxide (hydroxide),
Examples thereof include calcium (hydroxide) calcium and zinc (hydroxide) zinc. These metal oxides (hydroxides) are used in an amount of 1 to 5 parts by weight based on 100 parts by weight of the chloroprene rubber polymer. Within this range, sufficient tackiness can be secured,
The adhesive performance can be further improved. As a method of addition, a method of adding in the form of an emulsion dispersed is preferable.

The polychloroprene latex for adhesives of the present invention, the method for producing the same, and the composition of the adhesive composition using the same are as described above, and the room-temperature adhesive strength and tackiness which cannot be obtained by the conventional latex-based adhesives are as described above. Holding power, high temperature adhesion,
Good adhesive properties such as water resistance and latex stability,
It also has excellent heat resistance.

[0028]

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

The latex adhesives obtained in the following Examples and Comparative Examples have room-temperature peel strength, high-temperature peel strength, heat-resistant creep test, water resistance, latex stability (compounding stability, mechanical stability), and contact property. Was measured and evaluated by the following methods.

<Peel strength at room temperature> An SBR rubber plate (Showa Rubber, 150 mm × 25) finished with a No. 60 polishing cloth
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 test piece was prepared by curing at 23 ° C. for 3 days in a constant temperature room. 2 test pieces
The 180 ° peel strength was measured using a Tensilon type tensile tester under the conditions of 3 ° C. and a pulling speed of 200 mm / min.

<High Temperature Peel Strength> Using a test piece prepared in the same manner as the normal temperature peel strength measurement, 80 ° C. and a pulling speed of 20.
The 180 ° peel strength was measured using a Tensilon type tensile tester under the condition of 0 mm / min.

<Heat Resistance Creep Test> SBR surface-polished with No. 60 polishing cloth (Showa Rubber, 150 x 25 mm)
The adhesive composition is brushed on one side of about 625 g / m ² (w
et), and then heat-dried at 60 ° C. for 10 minutes, cover the shaded area with a polyethylene sheet as shown in FIG.
It was bent at the center, the diagonally shaded portion was cut off as shown in FIG. 2, and compression was performed with a hand roller so that the bonded portion had a size of 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 final time is 60 minutes, and when it does not fall, it is 60 minutes or more. If it does not fall but is displaced, the length of displacement after 60 minutes (m
m) was measured.

<Water resistance> A test piece prepared in the same manner as the room temperature peel strength measurement was immersed in pure water at 23 ° C for 3 days, and then excess water was immediately wiped off at 23 ° C and a pulling speed of 200 m.
The 180 ° peel strength was measured using a Tensilon type tensile tester under the condition of m / min.

<Latex stability><Compoundingstability> The presence or absence of rubber deposits was observed by compounding the latex for adhesives.

<Mechanical Stability> The mechanical stability of the adhesive composition was measured by the Marlon test method (Japan Rubber Association Standard 3200-1).
983, JIS K 6387), rubber coagulation rate ((weight of dried coagulated rubber after drying / weight of solid content in sample) × 10
0) was measured.

<Contact Property> The adhesive composition was applied to SBR (thickness: 2 mm, 25 × 50 mm) whose surface was finished with a No. 60 polishing cloth, and the condition of the bonding surface immediately after bonding each other was judged.

Example 1 Chloroprene, 2,3-dichlorobutadiene, methacrylic acid, n-dodecyl mercaptan, sodium alkyldiphenyl ether sulfonate (Perex SSH (trademark), manufactured by Kao) and hydrosulfite having the composition ratios shown in Table 1 were used. Copolymer latex A was obtained by polymerizing sodium, triethanolamine and water in a 10 L autoclave equipped with a stirrer at 12 ° C. The properties of the obtained latex are also shown in Table 1.

[0038]

[Table 1]

All polymerizations were carried out by continuously dropping a 0.35% aqueous potassium persulfate solution in a nitrogen atmosphere. The conversion was about 98% or more, and 0.05 part of 2,6-tert-butyl-4-methylphenol was added as a polymerization terminator to terminate the polymerization.

The obtained copolymer latex was blended with a tackifier and a metal oxide in the composition ratios shown in Table 2 to prepare an adhesive composition.

[0041]

[Table 2]

Table 3 shows the evaluation results of the room-temperature peel strength, high-temperature peel strength, heat-resistant creep, water resistance, compounding stability, mechanical stability, and contact property of the prepared adhesive composition.

[0043]

[Table 3]

From the results in Table 3, room temperature peel strength, water resistance,
It was found that the compounding stability, the mechanical stability, and the contact property were good, and that the high temperature peel strength and the heat resistant creep related to the heat resistance were excellent.

Example 2 A copolymer latex B was obtained in the same manner as in Example 1 except that the 2,3-dichlorobutadiene concentration was changed at the composition ratio shown in Table 1. Further, Table 2 shows the composition ratio of the adhesive composition, and Table 3 shows the evaluation results of the adhesive physical properties.

The high-temperature peel strength, heat-resistant creep, water resistance, compounding stability, mechanical stability, and contactability are all good results, and the room-temperature peel strength is also a sufficiently practical value.

Example 3 A copolymer latex C was obtained in the composition ratio shown in Table 1 according to Example 1 except that methacrylic acid was not added. Further, Table 2 shows the composition ratio of the adhesive composition, and Table 3 shows the evaluation results of the adhesive physical properties.

The normal temperature peel strength, water resistance, compounding stability, mechanical stability, and contact properties are all good results, and the high temperature peel strength and heat resistant creep are sufficiently practical values.

Example 4 A copolymer latex D was obtained according to Example 1 except that the concentration of methacrylic acid was changed at the composition ratio shown in Table 1.
Further, Table 2 shows the composition ratio of the adhesive composition, and Table 3 shows the evaluation results of the adhesive physical properties.

The normal temperature peel strength, the high temperature peel strength, the heat creep, the water resistance, the compounding stability, the mechanical stability and the contact property were all good results.

Example 5 A copolymer latex E was obtained in the same manner as in Example 1 except that the n-dodecyl mercaptan concentration was changed at the composition ratio shown in Table 1. Table 2 shows the composition ratio of the adhesive composition.
Table 3 shows the evaluation results of the adhesive properties.

The room-temperature peel strength, high-temperature peel strength, heat-resistant creep, water resistance, compounding stability, mechanical stability, and contact property are all practical values.

Example 6 Example 1 except that the concentration of sodium alkyldiphenyl ether sulfonate was changed at the composition ratio shown in Table 1.
According to the procedure described above, a copolymer latex F was obtained. Further, Table 2 shows the composition ratio of the adhesive composition, and Table 3 shows the evaluation results of the adhesive physical properties.

The room-temperature peel strength, high-temperature peel strength, heat-resistant creep, water resistance, compounding stability, mechanical stability, and contact properties were all good results.

Comparative Example 1 Latex G was obtained by following the procedure of Example 1 except that 2,3-dichlorobutadiene and methacrylic acid were not added in the composition ratios shown in Table 1. Further, Table 2 shows the composition ratio of the adhesive composition, and Table 3 shows the evaluation results of the adhesive physical properties.

A gel component was observed, and satisfactory results were not obtained in room temperature peel strength, high temperature peel strength, heat resistant creep, water resistance and contact property.

Comparative Example 2 A chloroprene / methacrylic acid copolymer having the composition ratio shown in Table 1 was obtained according to Example 1 to obtain a latex H. Further, Table 2 shows the composition ratio of the adhesive composition, and Table 3 shows the evaluation results of the adhesive physical properties.

Good results were shown in high temperature peel strength and heat resistant creep, but satisfactory results were not obtained in normal temperature peel strength, water resistance and contact property.

Comparative Example 3 A chloroprene / methacrylic acid copolymer having the composition ratio shown in Table 1 was obtained according to Example 1 to obtain a latex I. Further, Table 2 shows the composition ratio of the adhesive composition, and Table 3 shows the evaluation results of the adhesive physical properties.

Good results were obtained in high temperature peel strength, heat resistant creep and water resistance, but satisfactory results were not obtained in room temperature peel strength and contact properties.

Comparative Example 4 A chloroprene / 2,3-dichlorobutadiene / methacrylic acid terpolymer having the composition ratio shown in Table 1 was used in Example 1.
To obtain Latex J. Further, Table 2 shows the composition ratio of the adhesive composition, and Table 3 shows the evaluation results of the adhesive physical properties.

Good results were obtained in high temperature peel strength and heat resistant creep, but satisfactory results were not obtained in normal temperature peel strength, water resistance and contact property.

[0063]

As described above, the polychloroprene latex for adhesives obtained by the present invention and the adhesive composition using the same have a room temperature adhesive strength, a high temperature adhesive strength and a water resistance which are not found in conventional latexes. It is suitable as an adhesive for various applications such as wood, leather, cloth, rubber, plastics and metals because it has good adhesive properties such as properties and contact properties, latex stability, and excellent heat resistance.

[Brief description of drawings]

FIG. 1 is a view showing an SBR test piece used in a heat resistant creep test.

FIG. 2 is a view showing an SBR test piece used in a heat resistant creep test.

Claims (6)

[Claims] 1. A latex which is a copolymer obtained by emulsion-polymerizing a monomer consisting of 100 parts by weight of chloroprene and 1 to 100 parts by weight of 2,3-dichlorobutadiene, wherein the polymer in the latex is 5% in chloroform. A polychloroprene latex for adhesives, characterized in that the solution when dissolved in a concentration does not contain an organic solvent insoluble portion. 2. A latex which is a copolymer obtained by emulsion-polymerizing a monomer comprising 100 parts by weight of chloroprene, 1 to 100 parts by weight of 2,3-dichlorobutadiene and a vinyl monomer containing a carboxyl group, which is in the latex. A polychloroprene latex for adhesives, characterized in that the solution prepared by dissolving the above polymer in chloroform at a concentration of 5% does not contain an organic solvent insoluble portion. 3. An emulsifying / dispersing agent which imparts latex stability to 0.5 to 10 parts by weight and a molecular weight adjusting agent to 0.1 to 100 parts by weight of the total amount of the monomers according to claim 1 or 2.
In the presence of 3.0 parts by weight, the polymerization is carried out at 0 to 80 ° C., and the polymerization is carried out up to a monomer conversion of 60 to 100%. Method for producing polychloroprene latex. 4. The method for producing a polychloroprene latex for adhesives according to claim 3, wherein the emulsifying / dispersing agent imparting latex stability is a water-soluble salt of alkyldiphenyl ether disulphonic acid. 5. From 10 to 80 parts by weight of a tackifier and from 1 to 5 parts by weight of a metal oxide or metal hydroxide, relative to 100 parts by weight of the polychloroprene latex for adhesives according to claim 1 or 2. An adhesive composition comprising: 6. The adhesive composition according to claim 5, wherein the tackifier is selected from phenolic resins, terpene resins, rosin derivative resins and petroleum hydrocarbons.