JPH11323262A - Primer composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a primer composition for polyolefin resins, having high heat resistance and excellent in adhesiveness to an urethane resin subjected to forming-in-place in uses for urethane form-in-place molding. SOLUTION: This primer composition consists essentially of a chlorinated polyolefin having 5-50 wt.% chlorine content and containing at least two or more kinds of carboxyl groups in one molecule, an isocyanate compound containing two or more kinds of isocyanate groups in one molecule, an adhesion- providing resin and an organic solvent and contains the isocyanate compound in a compounding amount of 1-30 pts.wt. based on 100 pts.wt. chlorinated polyolefin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a primer used for an automobile interior material. More particularly, the present invention relates to a primer composition which is applied to a polyolefin resin material so as to improve its adhesion to the surface thereof and to be capable of being bonded to a urethane resin to be injected and foamed.

[0002]

2. Description of the Related Art Conventionally, in the case of a base material made of an ABS resin or an ABS resin reinforced with glass fiber in the urethane injection foam molding of an interior material such as an instrument panel of an automobile, the urethane resin is directly injected and foamed to bond. Although it is possible, in the case of a substrate made of a polyolefin-based resin such as a PP resin or a PP resin reinforced with glass fiber, even if urethane is directly injected and foamed, it cannot be bonded. Even if the primer of the conventional general chlorinated polyolefin resin is primed, the adhesion to the urethane foam is insufficient,
At present, heat resistance cannot be obtained.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a primer composition having a good adhesive property to a urethane resin to be injected and foamed and a high heat resistance by undercoating a substrate made of a polyolefin resin. Is to provide.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, by blending an isocyanate compound with a chlorinated polyolefin modified with a carboxyl group, the injection urethane foam is obtained. A primer composition that adheres to a resin and adheres to a substrate made of a polyolefin resin and has excellent heat resistance has been completed. Hereinafter, the present invention will be described in detail.

[0005] That is, the present invention means that the chlorine content is 5 to 5
A chlorinated polyolefin containing at least two carboxyl groups in one molecule in the range of 0% by weight;
An isocyanate compound containing two or more isocyanate groups in the molecule, a tackifier resin, and a primer composition containing an organic solvent as essential components, and the compounding amount of the isocyanate compound is 1 to 100 parts by weight of the chlorinated polyolefin.
Primer composition in the range of ~ 30 parts by weight.

In the present invention, a chlorinated polyolefin having a chlorine content in the range of 5 to 50% by weight and containing two or more carboxyl groups in one molecule includes crystallized polypropylene, non-crystallized polypropylene and polybutene-1. , Low-density or high-density polyethylene, ethylene-propylene copolymer, ethylene-propylene-diene copolymer, etc., acrylic acid, acrylic acid monomers such as acrylic acid ester, methacrylic acid, methacrylic acid ester, etc. A chlorinated polyolefin obtained by copolymerizing a methacrylic acid-based monomer or various unsaturated carboxylic acids such as itaconic acid, maleic acid, and maleic anhydride to introduce a carboxyl group can be used. Chlorination of polyolefin can be easily carried out by a usual reaction method. For example, a polyolefin is dissolved in a chlorinated solvent for each carbon tetrachloride, and is heated from normal temperature under pressure or normal pressure in the absence or presence of a catalyst or under irradiation of ultraviolet rays.
This is performed by introducing chlorine gas in a temperature range of 20 ° C. The chlorine content of the chlorinated polyolefin is 4% by weight
If it is below, the compatibility with the tackifier resin or the like becomes poor, and 51
If it is more than 10% by weight, the adhesiveness to a polyolefin base material will be reduced. In the case of a chlorinated polyolefin into which a carboxyl group has not been introduced, desired heat resistance cannot be obtained.

The isocyanate compound in the present invention is 1,6 hexamethylene diisocyanate (HD
I) Aliphatic polyisocyanates such as 2,2,4-trimethylhexamethylene diisocyanate, polyisocyanates such as hydrogenated diphenylmethane diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, tolylene diisocyanate (TDI), diphenylmethane-4 , 4-diisocyanate (MDI),
Aromatic polyisocyanates such as naphthylene diisocyanate, xylylene diisocyanate, triphenylmethane triisocyanate and the like can be mentioned, and one or a mixture of two or more thereof can be used.

The amount of the isocyanate compound (in terms of solid content) may be usually set in the range of 1 to 30 parts by weight based on 100 parts by weight of the carboxyl group-containing chlorinated polyolefin resin. If the amount is less than 1 part by weight, the adhesiveness to the urethane foam resin decreases, and if the amount exceeds 30 parts by weight, the adhesiveness to the substrate composed of the polyolefin resin decreases.

The tackifying resin in the present invention includes rosin resins such as hydrogenated rosin, polymerized rosin, maleic acid-modified rosin, hydrogenated rosin ester, alkylphenol,
Phenolic resins such as rosin-modified phenol and terpene-modified phenol, natural and synthetic terpene resins, cumarone-indene-styrene resins, aliphatic and aromatic petroleum resins, and the like can be used.

The amount of the tackifier resin (in terms of solid content)
Normally carboxyl group-containing chlorinated polyolefin 100
It may be set in the range of 10 to 100 parts by weight with respect to parts by weight. If the amount is less than 10 parts by weight, the initial adhesive strength decreases,
If the amount exceeds the weight part, the adhesiveness to the substrate made of polyolefin resin is reduced.

The organic solvent in the present invention includes aliphatic hydrocarbons such as normal hexane, alicyclic hydrocarbons such as cyclohexane, aromatic hydrocarbons such as benzene, toluene and xylene, ketones such as acetone and methyl ethyl ketone, and acetic acid. Examples thereof include acetic acid esters such as ethyl and halogenated hydrocarbons such as dichloromethane, and these solvents can be used alone or as a mixture of two or more kinds. Can be set.

In addition, fillers, coloring agents, antioxidants and the like can be added and compounded as required in addition to the above components.
The proportion of these added amounts in the primer composition can be set arbitrarily.

[0013]

The primer composition of the present invention having the above constitution is excellent in adhesion to a base material made of a polyolefin resin by undercoating a base material made of a polyolefin resin, and to a urethane resin to be injected and foamed. It is a primer composition having excellent heat resistance, and is a primer composition which is extremely useful in the automotive industry where high heat resistance is required.

[0014]

Next, the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples. Examples 1 to 3 and Comparative Examples 1 and 2 (1) Primer The chlorinated polyolefin resin, isocyanate compound, tackifier resin and organic solvent in the number of parts shown in Table 1 below were blended and mixed by stirring to obtain a primer.

(2) Adhesion test The primer of the above (1) was applied to a polypropylene plate in an amount of about 30 g / m ² and dried at 20 ° C. for 10 minutes. A urethane foam resin, which is a main component containing polyurethane as a main component and a curing agent containing isocyanate as a main component, was stirred and mixed, allowed to flow on the surface to which the primer was applied, and left for 10 minutes to prepare a test piece. Next, the test items were used and the results were listed in Table 1.
It is described together. Initial hand peeling Immediately after the preparation of the test piece, the urethane foam was peeled off at room temperature to observe the destruction state. Hand peeling at 20 ° C After preparing the test piece, leave it at 20 ° C for 24 hours.
In the atmosphere, the urethane foam was peeled off and the state of destruction was observed. 100 ° C hand peeling After the test piece was prepared, it was left at 20 ° C for 24 hours.
The test piece was left for 1 hour in a constant temperature bath in an atmosphere of ° C., the test piece was taken out, the urethane foam was immediately released, and the destruction state was observed.

Claims (2)

[Claims] 1. A chlorinated polyolefin having a chlorine content in the range of 5 to 50% by weight and containing at least two carboxyl groups in one molecule, and an isocyanate containing two or more isocyanate groups in one molecule. A primer composition comprising a compound, a tackifier resin, and an organic solvent as essential components. 2. The primer composition according to claim 1, wherein the amount of the isocyanate compound is in the range of 1 to 30 parts by weight per 100 parts by weight of the chlorinated polyolefin.