The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 29, 1985
Filed:
Jun. 11, 1984
Leon D Cerankowski, Carlisle, MA (US);
Gary S LaPointe, Beverly, MA (US);
Neil C Mattucci, Billerica, MA (US);
Polaroid Corporation, Cambridge, MA (US);
Abstract
This invention relates to diffusion transfer processes and products wherein the transmission density of the pigmented processing composition layer is increased by employing an alkali earth metal salt to increase the light-absorbing ability of a carboxynaphthol phthalein optical filter agent within said processing composition layer. In another embodiment, a carboxyindole phthalein optical filter agent also is included in said processing composition layer, and a zinc or cadmium salt is employed to shift the spectral absorption of the carboxyindole phthalein into the green region of the visible spectrum. In a further embodiment, a calcium salt is employed in a viscous pigmented processing composition comprising a light-reflecting pigment, colloidal silica and a metal chelating agent, e.g., an alkylene polyamine polyacetic acid to stabilize the spreading characteristics of the composition.