JPH02270544A - Molding - Google Patents

Abstract

PURPOSE:To obtain a molding which is excellent in adhesion and has durability by blending a multifunctional acryl compd., a foaming agent and a photopolymerization initiator at the specified amounts with the specified acrylate or methacrylate and applying this blended composition to a base material and irradiating the base material with ultraviolet rays to polymerize and foam the blended composition. CONSTITUTION:0.01 - 5pts.wt. multifunctional acryl compd., 0.0001 - 3 pts.wt. foaming agent and 0.1 - 5 pts.wt. photopolymerization initiator are blended with 100pts.wt. acrylate or methacrylate having 4 - 18 C alkyl group. A molding is obtained by applying this blended composition to a base material and irradiating it with ultraviolet rays to polymerize and foam this composition. In the amount excepting a range within 0.01 - 5pts.wt. multifunctional acryl compd., the adhesion is deteriorated. When the foaming agent is less than 0.0001pts.wt., the effect thereof can be not exhibited. When this foaming agent exceeds 3pts. wt., foaming is excessively performed and the adhesion is deteriorated. When the photopolymerization initiator is less than 0.1pts.wt., (meth)acrylate and the multifunctional compd. are not cured. When it exceeds 5pts.wt., the adhesion is deteriorated.

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a molding (hereinafter referred to as a molding) attached to the body, bumper, etc. of an automobile. [Prior Art] Conventionally, moldings made of synthetic resin, mainly vinyl chloride resin, have been attached to the bodies and bumpers of automobiles. A molding that is attached to the side of the body and has the function of preventing scratches caused by contact with other objects when opening a door, etc. and is also decorative is called a side protection molding, and is attached to the body using double-sided tape. There is. Therefore, the installation work is easy, and there is no need to drill holes in the body, so there is no risk of rust. [Problems to be Solved by the Invention] However, in the above-mentioned mall, the polyvinyl chloride resin mold repeatedly contracts and expands due to temperature differences between day and night, summer and winter, and the low-molecular compound in the vinyl chloride resin shrinks and expands repeatedly. Due to factors such as shrinkage due to volatilization, and further interaction with heat, light, moisture, etc., the plasticizers and stabilizers in the vinyl chloride resin decompose and become low molecular weight, and shrinkage due to these volatilizing in the air, double-sided tape There has been a problem in that the adhesiveness between the molding and the molding or the body is reduced. An object of the present invention is to provide a molding that has excellent adhesiveness to an automobile body, etc., and has durability. [Means for Solving the Problems] In order to achieve the above object, the present invention uses carbon atoms of 4 to 18 carbon atoms.
Acrylate or methacrylate having an alkyl group [hereinafter collectively referred to as (meth)acrylate] 100 parts by weight, 0.01 to 5 parts by weight of a polyfunctional acrylic compound, 0.0001 to 3 parts by weight of a blowing agent, and a photopolymerization initiator. agent 0.
A method is employed in which a composition containing 1 to 5 parts by weight is applied to a base material, and the composition is polymerized and foamed by irradiation with ultraviolet rays.

[Detailed explanation of means]

As the (meth)acrylate having an alkyl group having 4 to 18 carbon atoms, butyl (meth)acrylate, isobutyl (meth)acrylate, 2-ethylhexyl (meth)
Acrylate, nonyl (meth)acrylate, hexadecanol (meth)acrylate, stearyl (meth)acrylate
(Meth)acrylates having a linear or branched alkyl group, such as acrylates, can be used. Polyfunctional acrylic compounds are radically polymerizable (meth)
It refers to a compound having multiple acryloyl groups, and for example, the following compounds can be used. ■ Tetramethylene glycol diacrylate CH2=C
HCOO(CH2)40CO--CH=CH2 (For example, manufactured by Osaka Organic Chemical Industry Co., Ltd., trade name Viscoat #195) ■Hexamethylene glycol diacrylate CH2=C
HCOO(CH2)s 0CO--CH=CH2 (For example, same Viscoat #230) ■2.2-Bis(acryloylmethyl)propane (CH2=CHCOO
CH2)2 C(CH3)2 (for example, same Viscoat #215) ■ Trioxypropylene glycol diacrylate CH2=CHCOO(CH2CH(CH3) O)
3--COCH=CH2 (for example, Viscoat #310) ■ Tetraoxypropylene diacrylate CH2=CHCOO (CH2
CH20) 4--COCH=CH2 (For example, same Viscoat #335) ■(Triacryloylmethyl)ethylmethane (CH2-CHCOOCH
2) 3C (C2H5) (for example, also Viscoat #
295) ■(Triacryloylmethyl)hydroxymethylmethane (CH2=CHC00CH2)3 CCH20H (e.g., also visco-) #300) ■(CH2=CHCO
OCH2CH20)3 PO (for example, also Viscoat 3PA) ■CH2=CHCOOCH2CH(OH)CH2-CH
3 (OH)CH2)nOcOcH=cH2 (for example, also Visco-) #540, average molecular weight 480) @ (CH2=CHCOO(CH2CH20)2 -
(For example, same viscoat #700) OCH2=CH
COO(CH2)s O-molecule weight: about 700) The blending ratio of this polyfunctional acrylic compound is in the range of 0.01 to 5 parts by weight based on 100 parts by weight of the (meth)acrylate. If it is less than 0.01 part by weight, the composition becomes too flexible when irradiated with ultraviolet rays, resulting in a decrease in cohesive force and poor adhesion; if it exceeds 5 parts by weight, the composition becomes hard and brittle when irradiated with ultraviolet rays. This results in a decrease in adhesion. As the blowing agent, azodicarbonamide, azobisisobutyronitrile, dinitrosopenkumethylenetetramine, 4,4'-oxybisbenzenesulfonylhydrazide, paratoluenesulfonylhydrazide, etc. can be used. The blending ratio of this blowing agent is 1:1 of the (meth)acrylate mentioned above.
The range is from 0.0001 to 3 parts by weight per 0.00 parts by weight. If it is less than 0.0001 parts by weight, it will not be effective as a foaming agent, and if it exceeds 3 parts by weight, foaming will become excessive and adhesiveness will deteriorate. As a photopolymerization initiator, benzoin isopropyl ether, p-N, isoamyl N-dimethylaminobenzoate,
7,7,8.8-tetracyanoquinodimethane, 2.2-
Dimethoxy-2-phenylacetophenone, 2-hydroxycyclohexylphenyl ketone, benzophenone,
2-Methyl[4-(methylthio)phenyl]-2-morpholino i-propanone and the like can be used. The blending ratio of the photopolymerization initiator is as follows ((meth)acrylate)
The amount is in the range of 0.1 to 5 parts by weight per 100 parts by weight. If O is less than 1 part by weight, the (meth)acrylate and polyfunctional acrylic compound will not harden when irradiated with ultraviolet rays;
If the amount exceeds 1 part by weight, the photopolymerization initiator becomes an impurity and remains even after the composition is polymerized, reducing adhesive properties and increasing costs. The mold of the present invention is produced by applying a composition containing the (meth)acrylate, a predetermined amount of a polyfunctional acrylic compound, a foaming agent, and a photopolymerization initiator to a base material such as resin or rubber, and irradiating it with ultraviolet rays. easily obtained. At this time, the composition polymerizes and at the same time foams, particularly in its surface layer, playing the same role as the base material of an adhesive tape. This mall is
Since the surface coated with the composition has adhesive properties, it can be attached to the side surface or bumper of an automobile body by pressing it.

[Effect]

By adopting the above method, the composition consisting of (meth)acrylate, polyfunctional acrylic compound, foaming agent, and photopolymerization initiator coated on the base material is rapidly cured by ultraviolet rays, and has flexibility and adhesive properties. A high-molecular weight acrylic polymer obtained by copolymerizing a (meth)acrylate having 4 to 18 carbon atoms, which exhibits the It is also presumed that the surface layer of the composition applied on the base material is foamed by the foaming agent, and that it also functions as a double-sided tape. [Examples 1 to 14 and Comparative Examples 1 to 5] Next, Examples embodying the present invention will be described in comparison with Comparative Examples. In addition, in each of the following, parts represent parts by weight. (1)! ! Preparation of composition for coating After mixing the (meth)acrylate, polyfunctional acrylic compound, foaming agent, and photopolymerization initiator shown in Tables 1 and 2 below, prepare a composition for coating on the surface of the substrate. did. (2) Preparation of test piece After applying the above composition onto a vinyl chloride resin plate (7) as a base material, cover the surface with a release tape of polyethylene terephthalate to achieve 20C! After the composition was polymerized and cured by irradiation with ultraviolet light from a height of 1 for 8 minutes, the release tape was removed. Similarly, the same composition was polymerized and cured on another vinyl chloride resin plate, and the plates were overlapped with each other with an adhesion area of 25 m5 + x 25 g, and a test piece was obtained by pressing under a load of 5 kg for 1 minute. (3) Measurement of squeak noise One vinyl chloride resin plate of the above test piece was made to reciprocate against the other vinyl chloride resin plate 60 times per minute at an amplitude of 10 m, and the squeak noise was measured according to the following criteria. The results are shown in Tables 3 and 4. ○: No squeak was generated. Δ: A small squeak occurred. ×: A loud squeak occurred. (4) Measurement of tensile shear strength
The tensile shear strength was measured under the conditions of tn. Table the results.
3 and Table 4. Table-1 The abbreviations in Table-1 and Table-2 have the following meanings. n-BA: n-butyl acrylate 2-EHA
: 2-Ethylhexyl acrylate C8; n-octyl acrylate C10: 7 acrylate of n-decanol CIB: acrylate of n-octadecanol ■ to [phase] in the column of polyfunctional acrylic compounds are represented by the general formula described above. The compound represented by (1): Azodicarbonate (2): Azubisisobutyronitrile (3) Nidine nitrosopentane methylenetetramine (4)
: 4,4'-oxybisbenzenesulfonyl hydrazide (5): para-toluenesulfonyl hydrazide (a): benzoin isopropyl ether (b3: p-N, N-dimethylaminobenzoic acid isoamyl (cl: 7,7,8. 8-tetracyanoquinodimethane (d): 2,2-dimethoxy-2-phenylacetophenone + e): 2-hydroxycyclohexylphenyl ketone (f): benzophenone (g): 2-methyl-[4-(methylthio ) Phenyl]-2-morpholino-1-propanone Table 3 The * in the tensile shear strength column in Table 3 indicates that the foamed portion of the surface layer of the composition was destroyed. Table 4 The above table 3 and Table 4, in Examples 1 to 14 of the present invention, the tensile shear strength at room temperature is 1.0 to 1.
．． At 3 kg/cd, no peeling occurred at the interface between the adhesive layer formed by polymerization of the composition by ultraviolet irradiation and the vinyl chloride resin plate, and the foam layer on the surface of the adhesive layer was destroyed, causing the vinyl resin to become a painting board. The adhesive strength between the plates is excellent, and neither produces any squeaks. On the other hand, when the blending ratio of the polyfunctional acrylic compound is too small or too large (Comparative Example 1
．． 2) When the blending ratio of the blowing agent is excessive (Comparative Example 3)
), when the blending ratio of the photopolymerization initiator is too little or too much (Comparative Example 4.5), the tensile shear strength is 0.1 to 0.8 kg/-
It often produces a low, squeaking sound. The reason why the test pieces of each example showed such excellent performance is that (meta) having 4 to 18 carbon atoms exhibits flexibility and adhesiveness.
Acrylate and a polyfunctional acrylic compound that forms an appropriate crosslinked structure are copolymerized by UV irradiation, and the resulting high molecular weight acrylic polymer has sufficient cohesive strength for the adhesive layer and the adhesive layer and vinyl chloride resin. It is thought that it exhibits excellent adhesive strength at the interface with the plate. In addition, by incorporating a foaming agent, the surface layer of the adhesive layer foams, and the foamed part also functions as a base material for double-sided tape (previously, chloroprene rubber foam). It is thought that this adhesive high molecular weight acrylic polymer applied to the resin plate suppresses the generation of sound. Therefore, even if the base material of the molding of the present invention is made of vinyl chloride resin, it repeatedly shrinks and expands due to temperature differences between day and night, summer and winter, and shrinks due to volatilization of low-molecular compounds in the vinyl chloride resin. Furthermore, the plasticizer and stabilizer in the vinyl chloride resin are decomposed and reduced in molecular weight by heat, light, etc., and even if they volatilize in the air and shrink, etc., the adhesive strength is maintained for a long period of time.

【Effect of the invention】

The molding of the present invention exhibits excellent adhesion to automobile bodies, bumpers, etc., and has the advantage of being durable against environmental changes such as temperature differences.

Claims (1)

[Claims] 1. For 100 parts by weight of acrylate or methacrylate having an alkyl group having 4 to 18 carbon atoms, 0.01 to 5 parts by weight of a polyfunctional acrylic compound, and 0.0001 to 0.0001 parts by weight of a blowing agent.
A molding made by coating a base material with a composition containing 3 parts by weight and 0.1 to 5 parts by weight of a photopolymerization initiator, and polymerizing and foaming the composition by irradiating it with ultraviolet rays.