diffusion transfer process

Photographic process used primarily for instant or self-developing photographs in which the positive image is formed from undeveloped silver halides in the negative. The negative is placed in contact with a support in the presence of a developing agent, and the unexposed silver diffuses to the support to form the positive image. For making color instant camera photographs, it is dye couplers that are in the negative, in which case use "dye diffusion transfer process" or "internal dye diffusion transfer process."