Thermally-insulating layers and direct thermal imaging members containing same

Abstract

Multicolor thermal imaging members are described that comprise color-forming layers that are separated by thermally-insulating layers and can be addressed with a thermal printing head in contact with a surface to form an image. The thermally-insulating layers are designed to be as thin as possible consistent with at least partially independent addressing of the color-forming layers, and are formulated so as not to lead to instabilities either before or after printing or to give rise to dimensional changes of a thermal imaging member when it is subjected to changes in temperature or humidity. Coating compositions for manufacturing such thermally-insulating layers are also provided.

Description

REFERENCE TO RELATED APPLICATIONS[0001]This application is a continuation-in-part of copending U.S. patent application Ser. No. 11 / 397,251, filed on Jul. 23, 2002, entitled “Imaging System”, which is a continuation of U.S. patent application Ser. No. 10 / 806,749, filed on Mar. 23, 2004 issued as U.S. Pat. No. 7,166,558 which is a divisional of U.S. patent application Ser. No. 10 / 157,432, filed on May 20, 2002, issued as U.S. Pat. No. 6,801,233, which claims the benefit of prior U.S. provisional patent application Ser. Nos. 60 / 294,486, filed on May 30, 2001, and 60 / 364,198, filed on Mar. 13, 2002 the disclosures all of which are hereby incorporated by reference herein in their entirety.[0002]This application is related to the following commonly assigned United States patent applications and patents, the disclosures of all of which are hereby incorporated by reference herein in their entirety:[0003]U.S. Pat. No. 7,008,759 B2 which describes and claims color-forming compositions for use...

AI Technical Summary

Benefits of technology

This solution allows for independent control of each color-forming layer during printing, preventing unwanted coloration and maintaining image stability, thus simplifying the manufacturing process and improving the physical properties of the final product.

Problems solved by technology

Such migration of components may produce problems such as unwanted coloration in unprinted regions or changes in the activation temperature or degree of coloration of a color-forming layer, as is discussed in more detail below.

It is also possible that materials in adjoining layers may migrate into a color-forming layer and degrade its performance.

Such additional barrier layers introduce complexity into the process for manufacturing the thermal imaging member, and may also contribute undesirable physical properties to the final article, as discussed in detail below.

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