Abstract:
A photographic element is described comprising a support bearing one or more hydrophilic colloid layers including at least one photographic silver halide emulsion layer, wherein a photographically useful compound is incorporated into at least one hydrophilic colloid layer in the form of an intercalation composition comprising a layered host material having molecules of the photographically useful compound inserted as guest molecules between the layers of the host material. The invention provide novels materials and a method of incorporating active chemistry compounds such as developers or development inhibitors directly into a photographic imaging element with improved stability and keeping response versus known methods for incorporating active chemistry compounds.
Abstract:
This invention relates to a photographic element comprising a support and at least two silver halide emulsion layers further comprising an electron transfer agent releasing compound represented by the formula (I): CAR1-(L)n-ETAnullnull(I) wherein: CAR1 is a carrier moiety which is capable of releasing -(L)n-ETA on reaction with oxidized developing agent; L is a divalent linking group, n is 0, 1 or 2; and ETA is a releasable 1-aryl-3-pyrazolidinone electron transfer agent having a calculated log partition coefficient (c log P) greater than or equal to 2.40 and the total sum of the Hammett sigma(para) values of the substituents on the 1-aryl ring is 0.51 or less, the ETA being bonded to L or CAR1 through either the nitrogen atom in the 2-position or the oxygen attached to the 3-position of the pyrazolidinone ring; and a development accelerator releasing compound represented by the formula (II): CAR2-(SAM)-NX1nullNX2X3nullnull(II) wherein: CAR2 is a carrier moiety which is capable of releasing -(SAM)-NX1nullNX2X3 on reaction with oxidized developing agent; SAM is a silver absorbable moiety attached to the carrier moiety and is released on reaction with oxidized development agent; and nullNX1nullNX2X3 is a hydrazine group wherein X1, X2 and X3 are individually hydrogen or a substituent chosen from alkyl, aryl, carbonyl or sulfonyl groups with the proviso that at least one of X1, X2 and X3 is hydrogen.