Claims
- 1. In a rotational molding method for fabrication of hollow form plastic product in a rotational molding cycle wherein plastic particles are charged to a rotational mold, the mold is closed, heated to a molding temperature while being rotated about its major and minor axes for a time sufficient to form said molded product and the mold is cooled to a demolding temperature, opened and the molded product is ejected, the improved method for incorporating indicia in the exterior surface of said molded product which comprises:
a. providing an indicia transfer comprising a carrier sheet of a flexible material having a coated face with an indicia area, an indicia coat of a mixture of indicia material and hydrocarbon wax overlying said backing coat in a preselected indicia array, and a top coat of a top-coat pressure sensitive adhesive covering said indicia area and overlying said indicia coat; b. applying the coated face of said carrier sheet against a selected area of the interior surface of said rotational mold at substantially the demolding temperature and applying pressure to the unbolted face of said carrier sheet to cause transfer of said coats to said selected area; c. removing said carrier sheet from said mold and continuing said rotational molding cycle to obtain a molded, hollow form plastic product having indicia permanently molded into its exterior surface.
- 2. The method of claim 1 wherein said transfer also includes a backing coat of a second pressure sensitive adhesive on said coated face between said carrier sheet and said indicia coat.
- 3. The method of claim 2 wherein said backing and top coats extend peripherally beyond said indicia area, thereby encapsulating said indicia coat between said backing and top coats.
- 4. The method of claim 2 wherein the transition melting temperature of the second pressure sensitive adhesive is less than that of the first pressure sensitive adhesive.
- 5. The method of claim 2 wherein the transition melting temperature of the second pressure sensitive adhesive is less than the demolding temperature.
- 6. The method of claim 1 wherein the transition melting temperature of the first pressure sensitive adhesive is less than the molding temperature.
- 7. The method of claim 1 wherein said indicia coat is a mixture of from 30 to 99 weight percent hydrocarbon wax and from 1 to 70 weight percent indicia material.
- 8. The method of claim 1 wherein said polyolefin is polyethylene.
RELATION TO OTHER APPLICATIONS
[0001] This application is a continuation-in-part of our copending application Ser. No. 09/862,542, filed May 22, 2001.
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
09862542 |
May 2001 |
US |
Child |
10348884 |
Jan 2003 |
US |