Polaroid Corporation

David C Whritenour

David P Waller

Michael J Arnost

Marcis M Kampe

Peter Viski

Myron S Simon

Efthimios Chinoporos

Robert H Pauze

Charles E Jandrue, Sr

A novel class of bridged indicator dyes is disclosed which possess absorption in the infrared region of the electromagnetic spectrum. These bridged indicator dyes are useful as light-absorbing, pH-sensitive optical filter agents in diffusion transfer photographic processes adapted to be performed in the presence of ambient light and to diffusion transfer products useful in such processes. These indicator dyes will also find utility in titrations and other analytical techniques and products where pH-sensitive indicator dyes are employed and absorption of infrared is useful.

Photographic products and processes

There are described image-recording materials which include an image dye-providing compound comprising a novel naphthol azo cyan dye having a 3-aminobenzoisothiazole moiety. The image dye-providing compound includes a diffusion control moiety such as a hydroquinonyl developer group, a precursor thereof or a thiazolidine moiety and, may be diffusible or nondiffusible as a function of the diffusion control moiety. Image-recording materials according to the invention including those which contain high potential developers such as aminoreductone allow sufficient cyan chromophore to diffuse to the image-receiving layer to provide an acceptable photograph and result in no appreciable reduction of the 3-aminobenzoisothiazole moiety of the novel naphthol azo cyan dye.

Image-recording materials

There are described compounds which are represented by the formula ##STR1## The compounds are useful as dyes, and as intermediates and dye moieties in the preparation of compounds, which are particularly useful in imaging applications, such as, for example, diffusion transfer photographic systems.

Benzoisothiazole azo dyes

There are disclosed dye-providing compounds comprising color coupler dyes substituted on the phenylene diamine portion with one or two cyclic 1,3-sulfur-nitrogen groups. The dye-providing compounds are capable of releasing the coupler dye upon cleavage in the presence of silver ions or a soluble silver complex. The dye-providing compounds are useful as image-forming materials in color thermographic, photothermographic and other photographic processes.

Dye-providing compounds

There are disclosed dye-providing compounds comprising color coupler dyes substituted on the phenylene diamine portion with one or two cyclic 1,3 -sulfur-nitrogen groups. The dye-providing compounds are capable of releasing the coupler dye upon cleavage in the presence of silver ions or a soluble silver complex. The dye-providing compounds are useful as image-forming materials in color thermographic, photothermographic and other photographic processes.

Image-recording materials with cyclic 1,3-sulfur-nitrogen dye providing

Disclosed is a class of bridged phthalides and sulfinate esters which exhibit reversible thermochromism. At room temperature and in the presence of base, these compounds are substantially colorless but upon the application of heat they become colored, reverting to their original colorless or weakly colored state upon cooling. This colorless to colored, temperature-dependent cycle can be repeated many times. These compounds have utility as temperature sensors and as thermal pH indicators.

Growing community of inventors

Franklin, MA, United States of America

David C Whritenour