Patent ID: 6506528
Filing Date: 2003-01-14
Classification: G03C,Y10S

Abstract:
A photothermographic color element comprising at least three light-sensitive units that have their individual sensitivities in different wavelength regions comprising a silver halide imaging layer having associated therewith a mixture of at least two blocked developing agents comprising Blocked Developer A and Blocked Developer B independently represented by the following structure:DEV-(LINK 1)l-(TIME)m-(LINK 2)n-M wherein:DEV is a silver halide color developing agent; LINK 1 and LINK 2 are linking groups; TIME is a timing group; l is 0 or 1; m is 0, 1, or 2; n is 0 or 1; l+n is 1 or 2; M is a blocking group or M is: -Mâ€²-(LINK 2)n-(TIME)m-(LINK 1)l-DEV â€ƒwherein Mâ€² is blocking group for a second developing agent DEV; and where LINK 1 and LINK 2 have the following structure: â€ƒwherein X represents carbon or sulfur; Y represents oxygen, sulfur or Nâ€”R1, where R1 is substituted or unsubstituted alkyl or substituted or unsubstituted aryl; p is 1 or 2; Z represents carbon, oxygen or sulfur; r is 0 or 1; with the proviso that when X is carbon, both p and r are 1, when X is sulfur, Y is oxygen, p is 2 and r is 0; # denotes the bond to PUG (for LINK 1) or TIME (for LINK 2): $ denotes the bond to TIME (for LINK 1) or T(t) substituted carbon (for LINK 2) wherein the onset temperature of said blocked Developer B is less than the onset temperature of said blocked Developer A, the onset temperature of Developer B is in the range of 110 to 160Â° C. and the onset temperature of Developer A is 130 to 170Â° C. and wherein and the difference in the onset temperatures of the two developing agents are 5 to 50Â° C.