| 摘要 |
1333415 Photographic silver halide products and diffusion transfer processes POLAROID CORP 27 Nov 1970 [28 Nov 1969] 56439/70 Heading G2C [Also in Division C4] A photo-sensitive element comprises, in sequence, (a) a support, (b) a cyan dye imageforming material associated with a red-sensitive silver halide emulsion layer, (c) a magenta dye image-forming material associated with a green-sensitive silver halide emulsion layer and (d) a yellow dye image-forming material associated with a blue-sensitive silver halide emulsion layer, each of the cyan, magenta and yellow dye image-forming materials being compounds which upon exposure and development with an aqueous alkaline processing composition having a first pH give an imagewise distribution of a dye image-forming material which is soluble and diffusible at the first pH, and the bluesensitive silver halide emulsion additionally containing an oxacyanine dye of the formula:- wherein X<SP>#</SP> is an anion; R and R<SP>1</SP> are H or acidic substituents, provided that at least one of R and R<SP>1</SP> is an acidic substituent; and R<SP>2</SP> and R<SP>3</SP> are each alkyl, alkoxy, halogen or H. R and R<SP>1</SP> may be SO 3 H, CO 2 H, CO 2 <SP>-</SP> or SO 3 <SP>-</SP>. The dye may be 3-carboxymethyl -1'- ethyloxa -2'- cyanine bromide. The dye image-forming material may be a dye developer. A dye imagereceiving element may be attached to at least one edge of the photo-sensitive element to form a film unit which may include a rupturable container retaining aqueous alkaline processing composition. The oxacyanine dyes increase the blue sensitivity of the element, provide a high degree of latent image stabilization, reduce development induction time, and have an appreciable anti-foggant effect. |
