Polaroid Corporation

Serajul Haque

Stephen J Telfer

John L Marshall

Socorro M Ramos

Russell A Gaudiana

Stephen G Stroud

Anthony J Puttick

Michael J Zuraw

Peter K Chu

Robert P Short

William T Vetterling

Alain Bouchard

Michael J Arnost

Michael S Viola

Yongqi Deng

Fariza B Hasan

Michael A Young

Larry C Takiff

Edward J Dombrowski

Robert W Haddock

Iris B Kliman Bloom

There is described a thermal recording system which utilizes a donor element comprising a substrate and a thermal transfer material layer having a dye-containing phase which is amorphous and wherein the dye or dyes present in the amorphous phase form a continuous film. Imagewise heating of the medium transfers portions of the transfer layer to a receiver sheet, thus forming an image. The transfer layer may also include a non-dye phase comprising a thermal solvent. During the heating of the donor element, the crystalline thermal solvent melts and dissolves or liquefies at least a portion of the dye-containing phase, thereby lowering the temperature at which transfer of the transfer layer occurs.

Thermal transfer recording system

A process for producing an image uses an imaging medium comprising an acid-generating layer or phase comprising a mixture of a superacid precursor, a sensitizing dye and a secondary acid generator, and a color-change layer comprising an image dye. The sensitizing dye has first and second forms, the first form having substantially greater substantial absorption in a first wavelength range than the second form. The superacid precursor is not capable, in the absence of the first form of the sensitizing dye, of being decomposed by radiation in the first wavelength range. The secondary acid generator is capable of thermal decomposition, catalyzed by superacid, to form a secondary acid. While at least part of the sensitizing dye is in its first form, the medium is imagewise exposed to radiation in the first wavelength range, thereby causing, in the exposed areas of the acid-generating layer, the formation of superacid. The medium is then heated to cause, in the exposed areas, thermal decomposition of the secondary acid generator, catalyzed by the superacid, and formation of the secondary acid. The components of the acid-generating and color-change layers or phases are then mixed so that the secondary acid causes a change in color of the image dye, and the sensitizing dye is converted to its second form. The acid-generating layer or phase desirably includes a cosensitizer which is a reducing agent less basic than the secondary acid generator.

Imaging medium and process for producing an image

Dyes comprising an inner salt of a compound of the formula:

Benzpyrylium squarylium and croconylium dyes, and processes for their

The sensitivity to radiation of combinations of cationic electron acceptors (such as phosphonium, sulfonium, diazonium and iodonium salts) with sensitizing dyes, which sensitize these cationic electron acceptors to wavelengths (typically visible wavelengths) to which they are not sensitive in the absence of the dye, can be increased by including with the cationic electron acceptor and the sensitizing dye a supersensitizer which has an oxidation potential lower than that of the sensitizing dye, the supersensitizer being an ionic compound having a cation comprising an ionic grouping, said grouping comprising at least one atom of an element from Group VB, VIB or VIIB of the Periodic Table. An imaging medium has an acid-generating layer comprising this cationic electron acceptor/sensitizing dye/supersensitizer combination together with a secondary acid generator capable of thermal decomposition to form a secondary acid, the thermal decomposition of the secondary acid generator being catalyzed by the acid generated from the cationic electron acceptor, and a color change layer comprising an image dye which undergoes a color change in the presence of the secondary acid.

Medium and process for generating acid using sensitizing dye and

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Braintree, MA, United States of America

Serajul Haque