Method of forming an abrasion-resistant coating on molded articles

• US 4,338,269 A
• Filed: 12/05/1980
• Issued: 07/06/1982
• Est. Priority Date: 12/05/1980
• Status: Expired due to Term

• Current Assignee: Panelgraphic Corp.
• Original Assignee: Panelgraphic Corp.
• Inventors: Russell, Raymond J.
• Primary Examiner(s): THURLOW, JEFFERY
• Application Number:
  US06/213,479
• Time in Patent Office: 578 Days
• Field of Search: 264/22, 264/1.4, 264/338, 264/25, 264/236, 264/309, 204/159.16, 204/159.2
• US Class Current: 264/447
• CPC Class Codes: B29C 39/12 Making multilayered or multicoloured articles B29C39/021 takes precedence
• CPC Class Codes: C08J 5/00 Manufacture of articles or shaped materials containing macromolecular substances manufacture of semi-permeable membranes B01D67/00 - B01D71/00

Abstract

The present invention provides a method of forming a coating on molded polymeric articles formed by curing a polymerizable monomer-containing molding composition in a mold comprised of a material having less bonding affinity for the abrasion-resistant coating than for the cured molding composition. The method comprises:

(a) applying to a mold a coating composition comprising a pentaerythritol based polyacrylate or polmethacrylate and, a cellulose ester or a vinyl chloride-vinyl acetate containing copolymer;

(b) exposing said coating composition to actinic radiation to form a cured coating;

(c) adding to the mold a heat polymerizable monomer-containing molding composition; and

(d) polymerizing said molding composition in the form of a molded article, said cured coating bonding to the surface of said molded article.

Claims

1. A method of forming an abrasion-resistant coating on molded polymeric articles formed by curing a polymerizable monomer-containing molding composition in a mold comprising:

(a) applying to said mold a coating composition curable by actinic radiation comprising a pentaerythritol-based polyacrylate or polymethacrylate and a cellulose ester or a vinyl chloride-vinyl acetate containing copolymer;

(b) exposing said coating composition to actinic radiation to form a cured coating on said mold;

(c) adding to the mold a heat polymerizable monomer-containing molding composition; and

(d) polymerizing said molding composition in the form of a molded article, said cured coating transferring to the surface of said molded article.

2. The method of claim 1 wherein said pentaerythritol-based polyacrylate is pentaerythritol tetraacrylate.

3. The method of claim 2 wherein said cellulose ester is cellulose acetate butyrate.

4. The method of claim 1 wherein said vinyl chloride-vinyl acetate containing copolymer is a partially hydrolyzed vinyl chloride-vinyl acetate copolymer containing from about 50% to 95% combined vinyl chloride monomer, from about 2% to about 35% combined vinyl acetate monomer and from about 3% to about 25% combined vinyl alcohol.

5. The method of claim 4 wherein said partially hydrolyzed vinyl chloride-vinyl acetate copolymer contains 91% combined vinyl chloride, 3% combined vinyl acetate and 6% combined vinyl alcohol.

6. The method of claim 1 which further comprises a photoinitiator.

7. The method of claim 6 wherein said photoinitiator is alphachloro acetyl diphenyloxide.

8. The method of claim 1 wherein said coating composition is applied to said mold by spraying.

9. A method of forming a coating on a molded polymeric article formed by curing a polymerizable monomer-containing molding composition in a mold comprising:

(a) applying to said mold a coating composition curable by actinic radiation comprising pentaerythritol tetraacrylate, cellulose acetate butyrate or a partially hydrolyzed vinyl chloride-vinyl acetate copolymer containing from about 50% to 95% combined vinyl chloride monomer, from about 2% to about 35% combined vinyl acetate monomer and from about 3% to about 25% combined vinyl alcohol and a photoinitiator;

(b) exposing said coating to actinic radiation to form a cured coating on said mold;

(c) adding to the mold a polymerizable monomer-containing molding composition; and

(d) polymerizing said molding composition in the form of a molded article, said cured coating bonding to the surface of said molded article.