"Ilfochrome (also commonly known as Cibachrome) is a dye destruction positive-to-positive photographic process used for the reproduction of film transparencies on photographic paper. The prints are made on a dimensionally stable polyester base as opposed to traditional paper base. Since it uses 13 layers of azo dyes sealed in a polyester base, the print will not fade, discolor, or deteriorate for an extended time. Accelerated aging tests conducted by Henry Wilhelm rated the process as producing prints which, framed under glass, would last for 29 years before color shifts could be detected. Characteristics of Ilfochrome prints are image clarity, color purity, and being an archival process able to produce critical accuracy to the original transparency."