Imaging element containing a blocked photographically useful compound

A method of image formation comprising the step of developing an imagewise exposed imaging element comprising an imaging layer having associated therewith a compound of Structure I:

• wherein:
• PUG is a photographically useful group;
• LINK 1 and LINK 2 are linking groups;
• TIME is a timing group;
• 1 is 0 or 1;
• m is 0, 1, or 2;
• n is 0 or 1;
• Y is C, N, O or S;
• X is a substituted or unsubstituted aryl group or an electron-withdrawing group;
• W is hydrogen, halogen, or a substituted or unsubstituted alkyl, cycloalkyl, aryl or heterocyclic group, or a W group can combine with a T or R12 group to form a ring, w is 0 to 3 when Y is C, w is 0–2 when Y is N, and w is 0–1 when Y is O or S, when w is 2, the two W groups can combine to form a ring, and when w is 3, two W groups can combine to form a ring or three W groups can combine to form an aryl group or a bicyclic substituent;
• R12 is hydrogen, or a substituted or unsubstituted alkyl, cycloalkyl, aryl or heterocyclic group;
• T is a substituted or unsubstituted alkyl cycloalkyl, aryl or six-membered heterocyclic group, t is 0, 1, or 2, with the proviso that when X is a sulfono group, t is 1 or 2, a and tare each 1, and m and n are each 0, and when t is 2 the two T groups can combine to form a ring;
• a is 1 and b is 0 when X is monovalent;
• and
• a is 1 or 2 and b is 1 when X is divalent;
• wherein PUG is a development inhibitor, bleach accelerator, bleach inhibitor, inhibitor releasing developer, dye precursor, developing agent, silver ion fixing agent, electron transfer agent, silver halide solvent, silver halide complexing agent, reductone, image toner, pre-processing or post-processing image stabilizer, nucleator, or precursor thereof;
• and
• wherein said developing comprises treating said imagewise exposed imaging element at a temperature between about 90° C. and about 180° C.