JPH0423877A - Water-dispersed contact-type adhesive and its usage - Google Patents

Abstract

PURPOSE:To provide the title adhesive excellent in heat and water resistance, made up of a liquid A consisting mainly of a metal salt-incorporated chloroprene-based latex-type adhesive and a liquid B consisting mainly of a carboxyl group-contg. acrylic emulsion-type adhesive. CONSTITUTION:The objective adhesive made up of (A) a liquid consisting mainly of a product prepared by incorporating (1) a chloroprene-based latex-type adhesive and (2) a metal salt (e.g. MgO; the amount to be added being pref. 0.1-10 pts.wt., in terms of solid content, based on 100 pts.wt. of the chloroprene latex) and (B) a second liquid consisting mainly of a carboxyl group-contg. acrylic emulsion-type adhesive prepared by emulsion polymerization e.g. between a 1-14C alkyl (meth)acrylate (e.g. ethyl acrylate) and ethylenic unsaturated carboxylic acid (e.g. acrylic acid) in an aqueous medium.

Description

DETAILED DESCRIPTION OF THE INVENTION Industrial Field of Application The present invention relates to a water-dispersible contact adhesive having excellent initial adhesion strength and heat resistance and water resistance after aging, and a method for using the same.

<Conventional technology and problems> Chloroprene-based Tutex-type adhesives, which are made by mixing chloroprene latex with phenolic resin emulsion in alcohol and metal salts (metal oxides such as zinc white and i-gnesia), are non-polluting. As a universal adhesive, it is applied to both sides of the adherend, dried, and then bonded together, but there are limits to the initial adhesive strength, especially the initial heat resistance.
In addition, the adhesion to polyolefin plastics is poor and '#-0.'On the other hand, acrylic emulsion adhesives made of heavy metal emulsification of monomers mainly composed of 4(meth)acrylic acid esters have poor adhesion to polyolefin plastics (foamed It has excellent adhesion to the body), but the initial adhesion strength, normal adhesive strength, heat resistance,
<Objective of the Invention> The present invention provides a water-dispersed contact adhesive that has excellent initial adhesion strength, heat resistance, and water resistance, and is also capable of adhering to polyolefin plastics, etc., and a method for using the same. It is possible to provide the following.

<Disclosure of the Invention> The present invention provides an aqueous dispersion comprising a liquid A containing a metal salt-containing chloroprene latex type adhesive as a main component, and a liquid Bll containing a carboxyl group-containing acrylic emulsion type adhesive as a main component. Contact type adhesive.

Another method of using the adhesive is to apply liquid A and liquid B to separate adherends, dry them, and then bond them together.

The metal salt-containing chloroprene latex type adhesive used in the present invention refers to riμσ prene latex, such as various chloroprene latexes (preferably solidified Mooney viscosity (ML (H4) 100℃) 30
As mentioned above, a medium to fast crystallization rate (4) is suitable in terms of adhesive strength), and metal salts as vulcanizing agents include aqueous dispersions of magnesia (MgO) and zinc white (ZnO), and adhesives. A resin obtained by chelation reaction with an alkylphenol resin such as ordinary terpene-modified phenol resin or t-butylphenol resin as an imparting agent, and magnesium oxide (MgO), cadmium oxide (CdO), calcium oxide (CaO), etc. as a metal salt, and toluene etc. A tackifier resin emulsion prepared by dissolving it in a solvent and dispersing it in water using an emulsifier such as an ammonia casein aqueous solution is calculated based on the solid content weight of 100 parts of Roprene latex. It is obtained by blending 0.1 to 10 parts of a metal salt and 710 to 100 parts of a resin emulsion for tackifier.

In addition, carboxyl group-containing acrylic resin adhesives are those in which the alkyl group has 1 to 14 (meth)
It can be obtained by emulsion polymerizing a main monomer mainly composed of an acrylic acid alkyl ester and an ethylenically unsaturated carboxylic acid in an aqueous medium. As the (meth)acrylic acid alkyl ester as the main vehicle mass,
From the viewpoint of adhesive properties, alkyl groups having 1 to 14 carbon atoms are used, and particularly preferred examples include ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, isononyl acrylate, indecyl acrylate, Examples include ethyl methacrylate, butyl methacrylate, and lauryl methacrylate. In addition, as main monomers, in addition to the above esters, as unsaturated monomers copolymerizable with these, acryl tetranitrile, methacrylonitrile, vinyl acetate, styrene or derivatives thereof, etc. - Can be used in the following proportions: Examples of ethylenically unsaturated carboxylic acids include acrylic acid, methacrylic acid, itaconic acid, and! Leic acid etc. can be used.

The ratio of the main monomer to the ethylenically unsaturated carboxylic acid is such that the main monomer is 90-95% by weight and the ethylenically unsaturated carboxylic acid is 10-0.5% by weight. , is suitable in terms of adhesiveness and polymerization stability.

The dropwise polymerization of the O monomer mixture is carried out by heating the aqueous dispersion of the polymer to about 60 to 80"C, and adding 0.1 to 5 parts by weight per 100 parts by weight of the monomer mixture. Approximately 9 parts by weight of a polymerization initiator, such as potassium persulfate or ammonium persulfate, is added and dissolved, and the monomer mixture is continuously added dropwise to this at a predetermined dropping rate to carry out the reaction while maintaining the above temperature. Just let it happen.

Also, according to the end use and requirements, a blend of tackifiers (rosin resin, coumaron-indene resin, petroleum resin, alkylphenol resin, etc.) is used.

Next, the method of using the above-mentioned two-component adhesive is characterized by applying each of the above-mentioned adhesives separately to each of the adherends. , tpolyethylene terephthalate, etc.), it is desirable to apply a carboxyl group-containing acrylic adhesive to the polyolefin-based Goodstix material from the viewpoint of adhesion.

<Operations and Effects of the Invention> In the present invention, metal salts (hlx p Zn p Cd p
The carboxyl group contained in the acrylic adhesive (metallic compound such as Ca) and the acrylic adhesive undergo a crosslinking reaction immediately after bonding and contact, resulting in excellent initial strength, heat resistance, and water resistance.

As for the types of metal salts,! Gnesium compounds are the most effective. In addition, the reactivity with carboxyl groups is better when the metal is in the form of a chelate with an alkylphenol than in the form of a metal salt. (due to good crosslinking reaction)
It can have excellent adhesive strength.

In addition, carboxyl group-containing acrylic adhesives have excellent adhesion and wettability to polyolefin plastics, which are adhesive materials, so they are applied to polyolefin plastics and subjected to a crosslinking reaction. This allows excellent adhesion to be obtained even after applying a primer or surface treatment (such as corona discharge).

Next, an explanation will be given based on an example. Parts indicate parts by weight.

Example 1.2 and Comparative Examples 1 and 2.3 t-butylphenol resin (CKM-1 from Ultra High Polymer KK)
634) After dissolving 40 parts in 40 parts of toluene, oxidize! A chelated phenol resin solution was prepared by adding 4 parts of magnesium (MgO) and performing a chelation reaction at 50°C for 18 hours, in a mixed solution of 72 parts of triethanolamine, 25 parts of 1011 ammonia casein aqueous solution, and 50 parts of water. Then, gradually add and stir and disperse well to prepare a chelated phenolic resin emulsion using couloprene latex (Denka LA-50 from Denki Kagaku KK).

Parts were mixed to prepare a liquid A whose main component was a metal salt-containing chloroprene latex m adhesive with a solid content of 37.

In addition, 1 part of sodium lauryl sulfate and 100 parts of water were added to a monomer mixture consisting of 60 parts of butyl acrylate, 26 parts of 2-ethylhexyl acrylate, 10 parts of methyl methacrylate, and 4 parts of acrylic acid, and a prenyl dial was added. Then, in a reactor equipped with a thermometer, a stirrer, a nitrogen introduction device, and an R-flow cooling pipe, 10 parts of water and 0.0 parts of ammonium persulfate were added.
5 parts were added to prepare 80"CK11L, and the above pre-emulsion carbonate was added dropwise at a constant rate over 2 hours. The temperature was further maintained for 1 hour to complete the polymerization. Thereafter, it was cooled to room temperature, and
The pH was adjusted to 8 with % ammonia water to prepare a B solution containing a carboxyl group-containing acrylic emulsion-type adhesive as a main component and having a solid content of 50 s.

Next, as an adhesion test, Example 1゜2, which used the above liquid A and liquid B together, and the alignment KA were tested under the following adhesion conditions and test items.
Table 1 shows the results measured as Comparative Example 1゜2.3 in which liquid and B liquid are used alone.〇〇Adhesive conditions Adhesive material: Steel [XPET film/r campus coating;
1509/II/(double-sided coating) drying on one side ;zs
"CXS partial pressure tightening: 2 kgf / d x 5 f1pO Test items Initial strength; 180" peel strength within 3 minutes after adhesion (#//
Initial heat-resistant creep; Test piece (25 cm wide) immediately after adhesion. A static load of 3009 was applied at 90° in the peeling direction, and 2
Peeling length after leaving for 4 hours (cod) Normal strength: 180 @ Peeling strength after 3 days of curing (#f/zs
Intestines) Heat-resistant creep: After 3 days of curing, a static load of 3009 was applied to a test piece (25 cm wide) in the peeling direction of 90 C, and the test piece was heated at 80 C for 24
Peeling length after standing for hr (dew) Table 1 X: Peeling of 20 or more

Claims (1)

[Claims] 1. It is characterized by consisting of a liquid A whose main component is a chloroprene latex type adhesive mixed with a metal salt, and a liquid B whose main component is an acrylic emulsion type adhesive containing a carboxyl group. Water dispersion contact adhesive. 2. A water adhesive characterized by applying a metal salt-containing chloroprene latex type adhesive to one side of the adherend, and applying a carboxyl group-containing acrylic emulsion type adhesive to the other side, drying each, and then bonding them together. How to use dispersion contact adhesives.