Patent Number: 6,168,853

Title: Laser marking of phosphorescent plastic articles

Abstract: The invention provides molded, extruded or formed phosphorescent plastic articles having laser marked indicia and methods for preparing the articles. The indicia may be seen as a contrast against a phosphorescent background or, alternatively, the indicia may themselves be phosphorescent. An article of the invention has a composition comprising about 50% to about 99% by weight of a thermoplastic or thermosetting resin, about 1% to about 50% by weight of a phosphorescent phosphor pigment and about 0.001% to about 1% by weight of a laser energy absorbing additive. Resin compositions which themselves are laser energy absorbing do not require the additive; however, the addition of small quantities of the laser energy additive enhances the quality and contrast of the laser mark. The composition may further comprise small quantities of one or more of a whitening pigment, a lubricating agent, or an inert filler without interfering with the phosphorescence of the article and/or the quality and contrast of the laser mark.

Inventors: Feng; Ke (Lilburn, GA), Bodi; Jerry Alan (Suwanee, GA)

Assignee: M.A.HannaColor, a division of M.A. Hanna Company

International Classification: C08K 3/00 (20060101); C08K 3/32 (20060101); B32B 003/10 (); C09K 011/00 ()

Expiration Date: 01/02/2018