Abstract: The present invention is directed an oriented, foamed article having an integral security element, and a method of making the article. The oriented foam article is particularly useful in the preparation of printed security documents such as currency, stock and bond certificates, birth and death certificates, land titles and abstracts and the like.

Abstract: The present invention is directed to a process for producing a polypropylene foam by mixing a high melt strength polypropylene and a blowing agent to form a melt mixture, reducing the temperature of the melt mixture at the exit of the apparatus to an exit temperature that is no more than 30° C. above the melt temperature of the neat polypropylene while maintaining the melt mixture at a pressure sufficient to prevent foaming; passing the mixture through said exit shaping orifice and exposing the mixture to atmospheric pressure, whereby the blowing agent expands causing cell formation resulting in foam formation, and orienting said foam. The foam is useful as tape backings, thermal and acoustical insulation and as a diffuse reflector for use in optical applications such as computer displays.

Abstract: The present invention is directed to an oriented, foamed article having an integral security element, and a method of making the article. The oriented foam article is particularly useful in the preparation of printed security documents such as currency, stock and bond certificates, birth and death certificates, land titles abstracts and the like.