KR960007181B1 - Coating composition for plastic plastic articles using them - Google Patents

Abstract

The plastic coating compound comprises reactive oligomer which is acid-modified novolac-type epoxy acrylate of formula (I) or acid-modified bisphenol A or F type epoxy acrylate of formula (II), reactive monomer, photo initiator, leveling agent, diluting agent and additives. The epoxy acrylate of formula (I) or (II) is prepared by the addition reaction with novolac-type, bisphenol A or F type epoxy resin and unsaturated carboxylic acid in 1 : 0.5-1 equivalent ratio, and by the low temperature esterification reaction with acid-modified acrylate monomer. The obtd. plastic coating compd. improve the coherence between aluminium film and paint or plastic and paint in aluminium vacuum deposition.

Description

Plastic coating composition and plastic molded article coated with the same

TECHNICAL FIELD The present invention relates to a plastic coating composition and a coated plastic molded article. More specifically, the present invention relates to polymethyl methacrylate, polycarbonate, polystyrene, styrene-acrylonitrile, polyester or acrylonitrile-butadiene-styrene. The present invention relates to a plastic coating film composition used for the purpose of increasing the aesthetics and durability of a molded article by coating it on a plastic molded article and a plastic molded article coated with the same.

Most of these moldings have been used as a substitute for glass, and the amount of use is increasing because of its ease of processing in addition to excellent performance in its gloss and impact resistance. However, these molded articles tend to have a weak surface wear resistance, scratch resistance, solvent resistance, and the like.

Thus, attempts to remedy these defects have long been in progress. Silicone resins and melamine resins have been mainly used for this purpose, and these are thermosetting resins, which need to be exposed to heat for a long time in order to form a coating film. This will adversely affect the physical properties. Therefore, in order to solve the problem of the thermosetting type, US Pat. Nos. 4,273,802, 4,392,723, 4,557,975, 4,617,194, and the like describe a coating composition for plastics containing two acryloyloxy groups.

In particular, US Pat. No. 4,617,197, which is the most recent, discloses acrylic or methacrylic ester monomers of aliphatic polyols containing at least three acryloyloxy or methacryloyl and at least four acryloyloxy or methacrylo. Although varnishes for plastics have been prepared using acrylic or methacrylic ester resins of polyglycidyl ethers of bisphenol A-formaldehyde condensates containing hydroxy, physical properties such as abrasion resistance, scratch resistance and weather resistance (yellowing) of the cured product are somewhat There was a downside.

The present invention aims to compensate for these drawbacks and to provide a coating composition for plastics that is particularly excellent in adhesion.

Another object of the present invention is to provide a coating composition for plastics in which the adhesion between the aluminum film and the paint and the adhesion between the paint and the plastic are improved during aluminum vacuum deposition.

Still another object of the present invention is to provide a plastic molding prepared by coating the composition on a desired plastic.

The composition of the present invention for achieving the above object is a acid-modified noblock type epoxy acrylate represented by the following formula (I), or an acid-modified bisphenol-A type or -F type epoxy acrylate represented by the following formula (II). It consists of oligomers, reactive monomers, photoinitiators, leveling agents, diluents and additives.

Wherein R ₁ is H or CH ₃ , R ₂ is ethylene, propylene or butylene, n is an integer from 0 to 10, and m is an integer from 0 to 10.

Looking at the present invention in more detail as follows.

The acid-modified novolak-type epoxy acrylate of the formula (I) used as the reactive oligomer in the present invention is a novolak-type epoxy acrylate by addition reaction of a novolak-type epoxy resin and an unsaturated carboxylic acid in a molar ratio 1: 0.5 to 1 After the preparation, an acid-modified novolak-type epoxy acrylate is prepared by a low temperature ester reaction with an acid-modified acrylate monomer. It is preferable that the molar ratio of acid-modified acrylate monomer to novolak-type epoxy acrylate is 1: 0.1-1. The acid-modified acrylate monomer is obtained by low temperature ester reaction between a monofunctional acrylic monomer having a hydroxyl group and phosphoric acid.

Monofunctional acrylic monomers having the hydroxy group include 2-hydroxy ethyl acrylate, 2-hydroxy ethyl methacrylate, hydroxy propyl acrylate, hydroxy propyl methacrylate, hydroxy butyl acrylate and hydroxy butyl meta. Selected from the group consisting of acrylates.

The acid-modified bisphenol A or F epoxy acrylate of Formula (II) used as another reactive oligomer in the present invention is a bisphenol by addition reaction of bisphenol-A or F epoxy resin with an unsaturated carboxylic acid in a molar ratio of 1: 0.5 to 1. A-type or f-type epoxy acrylate is prepared, and then acid-modified bisphenol-A or f-type epoxy acrylate is prepared by low temperature ester reaction with the acid-modified acrylate monomer. The molar ratio of acid-modified acrylate monomer to bisphenol-A or f-type epoxy acrylate is preferably 1: 0.1 to 1. The acid-modified acrylate monomer is obtained by low temperature ester reaction between a monofunctional acrylic monomer having a hydroxyl group and phosphoric acid. The monofunctional acrylic monomer having a hydroxy group is 2-hydroxy ethyl acrylate, 2-hydroxy ethyl methacrylate, hydroxy propyl acrylate, hydroxy propyl methacrylate, hydroxy butyl acrylate, hydroxy butyl meta Selected from the group consisting of acrylates.

Acid-modified novolac-type epoxy acrylate or acid-modified bisphenol-A type or -F type epoxy acrylate, which is a reactive oligomer used in the present invention, may be used in an amount of 19.4 to 89.4% by weight in consideration of adhesion and general properties of the coating film. However, in the case of outside the above range, that is, when the adhesion is less than 19.4% by weight, the adhesion between the plastic and the aluminum film is poor, and when using more than 89.4% by weight is poor workability.

The reactive monomer of the present invention may be polymerized with the oligomer to affect the physical properties of the coating film, and one or more monomers may be used. The main monomer is an acrylic ester monomer, which is prepared by esterifying an alcohol with an unsaturated carboxylic acid. 1,3-butanediol diacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, diethylene glycol diacrylate, triethylene glycol dimethacrylate, neopentyl glycol diacryl Ethylene Glycol Dimethacrylate, Tetraethylene Glycol Dimethacrylate, Polyethylene Glycol Dimethacrylate, Tripropylene Glycol Diacrylate, Pentaerythritol Tetraacrylate, Trimethylolpropane Trimethacrylate, Trimethylolpropane Triacrylate Latex, Defenta erythritol Methacrylate or pentaerythritol triacrylate. 1,6-hexane diol diacrylate, tripropylene glycol diacrylate, trimethylol propane triacrylate, pentaerythritol in consideration of properties and economics of the coating film Tetra acrylate and the like are preferred. The amount used may be 10 to 80% by weight of the whole varnish composition, but in consideration of viscosity, it is preferable to use 20 to 60% by weight.

The photoinitiator uses a conventional polymerization initiator which is activated by ultraviolet rays, and uses 0.5 to 10% by weight of compounds such as benzophenone, benzyldimethyl ketal, acetophenone, anthraquinone and thioxanthone. do. In particular, such photoinitiators are preferably hydroxy-cyclohexyl phenylketone, 2,2-dimethoxy-2-phenyl acetophenone, benzophenone or phenyl-2-hydroxy-2-propylketone.

The leveling agent uses a silicone diacrylate-based or silicone polyacrylate-based compound in an amount of 0.1 to 5% by weight of the whole varnish composition.

In addition, the volatile diluent chemically impacts the surface of the plastic molded part before curing in the painting operation, thereby increasing the coating film adhesion. Usable diluents can be used using one or more selected from the group consisting of ketones, alcohols, acetates and aromatic compounds, with a weight ratio of total composition to diluent of 4/1 to 1/3.

Other additives can use a well-known compound by changing the addition amount according to various requirements.

The painting work for plastic molded products is spraying, dipping, roll coating, etc., which is an advantageous method depending on the plastic material, the shape of the molded product, the thickness of the coating film, and the like. According to such a coating method, different viscosities are required, and it can be used with an appropriate viscosity by adding a volatile diluent.

Hereinafter, the working effects of the present invention will be described in detail through Examples and Comparative Examples, but the following examples do not limit the scope of the present invention.

[Production Example 1]

116 parts by weight of 2-hydroxyethyl acrylate and 98 parts by weight of phosphoric acid were subjected to low-temperature esterification to prepare an acid-modified acrylate monomer.

[Production Example 2]

Novolak-type epoxy acrylate was produced by addition-reacting 72 parts by weight of acrylic acid to 175 parts by weight of a novolak epoxy resin (DEN-431, Dow Chemical Co., Ltd., 172 to 179 epoxy equivalent).

[Manufacture example 3]

An acid-modified novolak-type epoxy acrylate was prepared by low-temperature esterification of 247 parts by weight of the novolak-type epoxy acrylate prepared in Preparation Example 2 and 60 parts by weight of the acid-modified acrylate monomer prepared in Preparation Example 1.

[Production Example 4]

An acid-modified novolak-type epoxy acrylate was prepared by performing a low temperature ester reaction of 247 parts by weight of the novolak-type epoxy acrylate prepared in Preparation Example 2 and 120 parts by weight of the acid-modified acrylate monomer prepared in Preparation Example 1.

Production Example 5

188 parts by weight of bisphenol A type epoxy resin (Korepoxy R8828, Epoxy Equivalent 184 to 194) and 72 parts by weight of acrylic acid were added to prepare a bisphenol A type epoxy acrylate.

[Manufacture example 6]

Acid-modified bisphenol A-type epoxy acrylate was prepared by low-temperature esterification of 247 parts by weight of bisphenol A-type epoxy acrylate prepared in Preparation Example 5 and 60 parts by weight of the acid-modified acrylate monomer prepared in Preparation Example 1.

[Manufacture example 7]

An acid-modified bisphenol A-type epoxy acrylate was prepared in the same manner as in Preparation Example 6, except that the acid-modified acrylate monomer was changed to 120 parts by weight in Preparation Example 6.

Example 1

30 parts by weight of the acid-modified novolac epoxy acrylate prepared in Preparation Example 3, 10 parts by weight of trimethylol propanetri acrylate, 6,5 parts by weight of 1,6-hexanediol diacrylate, 2,2dimethoxy-2 A plastic varnish was prepared by stirring 3 parts by weight of phenyl acetophenone, 0.5 parts by weight of silicone polyacrylate (EB 360 manufactured by UCB), 30 parts by weight of methyl ethyl ketone, and 20 parts by weight of isopropyl alcohol at 25 to 30 ° C.

Example 2

Except for using the acid-modified novolak-type epoxy acrylate prepared in Preparation Example 4 instead of the acid-modified novolak-type epoxy acrylate in Example 1 was prepared a varnish for plastics with the same composition and content as in Example 1.

Example 3

Except for using the acid-modified bisphenol A-type epoxy acrylate prepared in Preparation Example 6 instead of the acid-modified novolak-type epoxy acrylate in Example 1 was prepared a varnish for plastics with the same composition and content as in Example 1.

Example 4

Except for using the acid-modified bisphenol A-type epoxy acrylate prepared in Preparation Example 7 instead of the acid-modified novolak-type epoxy acrylate in Example 1 was prepared for varnish for plastics with the same composition and content as in Example 1.

Comparative Example 1

Except for using 30 parts by weight of a novolak-type epoxy acrylate produced by addition reaction of 72 parts by weight of acrylic acid to 175 parts by weight of novolak epoxy (DEN-431 of Dow Chemical Co., Ltd.) in the same composition and content as in Example 1 A varnish for plastics was prepared.

Comparative Example 2

Except for using 188 parts by weight of bisphenol A type epoxy resin (Corfox R8828 manufactured by Korea Chemical Co., Ltd., epoxy equivalent: 184 to 194) in place of the novolak epoxy resin in the reactive oligomer of Comparative Example 1, the same composition and content as those of Comparative Example 1 A varnish was prepared.

The plastic varnishes of Examples 1 to 4 and the plastic varnishes of Comparative Examples 1 and 2 were measured by the following items and methods, and the results are shown in Table 1 below.

[Measurement Items and Methods]

Aluminum adhesion: measured by JIS D0202 (cross-cut)

ABS adhesion: Cross-cut according to JIS D0202

Pencil Hardness: Measured according to JIS D0202 (using UNI-PENCIL)

Weatherability: Observation of discoloration after leaving sunlight for 7 days

Scratch resistance: BYK's Dual-0-meter (DUR-0-TESTER)

Solvent resistance: Coating state after immersion at room temperature × 24 hours

Abrasion Resistance: Using Dual Abrasion Meter (Model 505)

Detergent resistance: 1 week after immersion in 3% high tie solution (45 ℃)

TABLE 1

As described above, as a result of comparing and evaluating the physical properties of the coating film composition for plastics of the present invention, the acid-modified epoxy acrylate of Formula (I) or (II) was used as a reactive oligomer as shown in Table 1 above. It showed very good physical properties in adhesion with ABS.

Claims (15)

A reactive oligomer, a reactive monomer, a photoinitiator, a leveling agent, a diluent, and an acid-modified novolak-type epoxy acrylate represented by the following formula (I) or an acid-modified bisphenol-A type or a f-type epoxy acrylate represented by the following formula (II); A coating film composition for plastics, comprising an additive. Wherein R ₁ is H or CH ₃ , R ₂ is ethylene, propylene or butylene, n is an integer from 0 to 10 and m is an integer from 0 to 10. The acid-modified novolak-type epoxy acrylate of the formula (I) is the addition of the novolak-type epoxy resin and unsaturated carboxylic acid in an equivalence ratio of 1: 0.5 to 1 to react the novolak-type epoxy acrylate After preparing, the plastic coating film composition characterized in that the acid-modified acrylate monomer and low temperature ester reaction. The acid-modified bisphenol A type or F type epoxy acrylate of the formula (II) is a bisphenol A type by adding a bisphenol-A type or F type epoxy resin and an unsaturated carboxylic acid in an equivalent ratio of 1: 0.5 to 1. Or after preparing the f-type epoxy acrylate, the coating composition for plastics, characterized in that the acid-modified acrylate monomers are prepared by low-temperature ester reaction. The coating composition for plastics according to claim 2 or 3, wherein the acid-modified acrylate monomer is prepared by low temperature ester reaction of a monofunctional acrylic monomer having a hydroxyl group with phosphoric acid. The monofunctional acrylic monomer according to claim 4, wherein the monofunctional acrylic monomer having a hydroxy group is 2-hydroxy ethyl acrylate, 2-hydroxy ethyl methacrylate, hydroxy propyl acrylate, hydroxy propyl methacrylate, hydroxy butyl acryl. Coating composition for plastics, characterized in that it is selected from the group consisting of latex and hydroxy butyl methacrylate. The plastic film composition of claim 2, wherein the acid-modified epoxy acrylate is prepared by mixing an equivalent ratio of the acid-modified acrylate monomer to the novolak-type epoxy acrylate in a ratio of 1 to 0.1 to 1. The plastic according to claim 3, wherein the acid-modified bisphenol A-type or F-type epoxy acrylate is prepared by mixing an equivalent ratio of the acid-modified acrylate monomer to the bisphenol A-type or F-type epoxy acrylate in a ratio of 0.1 to 1. Coating composition. The coating film composition for plastic according to claim 1, wherein the reactive oligomer is 19.4 to 89.4 weight% based on the final total composition. The final total composition of claim 1, wherein said reactive monomer is selected from the group consisting of 1,6-hexane diol diacrylate, tripropylene glycol diacrylate, trimethyl propanetri acrylate and pentaerythritol tetra acrylate Coating composition for plastics, characterized in that used in 10 to 80% by weight. The photoinitiator of claim 1, wherein the photoinitiator is selected from the group consisting of hydroxy-cyclohexyl phenylketone, 2,2-dimethoxy-2phenyl acetophenone, benzophenone or phenyl-2-hydroxy-2-propylketone , 0.5 to 10% by weight based on the total composition of the plastic coating film composition characterized in that used. The coating film composition for plastic according to claim 1, wherein the leveling agent uses a silicone diacrylate-based or silicone polyacrylate-based compound at 0.1 to 5% by weight based on the final total composition. The coating film composition for plastic according to claim 1, wherein the diluent is selected from the group consisting of ketones, alcohols, acetates and aromatic compounds. A plastic molded article according to claim 1, wherein the coating composition for plastics is coated on a plastic product such as poly methyl methacrylate, polycarbonate, polystyrene, styrene-acrylonitrile, polyester, or acrylonitrile-butadiene-styrene. The plastic molded article according to claim 13, wherein the coating is applied by spraying, dipping, or roll coating, and coated with different viscosities using a volatile diluent according to the coating method. 15. The method according to claim 14, wherein the volatile diluent uses one or more selected from the group consisting of ketones, alcohols, acetates and aromatic compounds, and the weight ratio of the total composition to the diluent is 4/1 to 1/3. Plastic molding made.