Dye-transfer process

Dye transfer is a continuous-tone color photographic printing process.

The use of dye imbibition for making full-color prints from a set of black-and-white photographs taken through different color filters was first proposed and patented by Charles Cros in 1880. It was commercialized by Edward Sanger-Shepherd, who in 1900 was marketing kits for making color prints on paper and slides for projection.

Technicolor introduced dye transfer in its Process 3, introduced in the feature film The Viking (1928), which was produced by the Technicolor Corporation and released by Metro-Goldwyn-Mayer. Technicolor's two previous systems were an additive color process and a physically problematic subtractive color process, the latter requiring two prints cemented together back-to-back. Process 3 used an imbibition process pioneered by the Handschiegl color process, which had been created in 1916 for Cecil B. DeMille's feature film Joan the Woman (1917). Technicolor further refined the imbibition dye transfer process in its Process 4, introduced in 1932, which employed three simultaneously filmed negatives.

In the 1940s, this process was popularized by Eastman Kodak for general-purpose graphic arts work, but not for motion picture work, which remained exclusive to Technicolor (and for which Eastman Kodak was manufacturing Technicolor's light-sensitive camera and printing films, including the "blank receiver" film, on an exclusive basis, but not Technicolor's dyes), and is sometimes referred to by such generic names as "wash-off relief printing" and "dye imbibition" printing. The process requires making three printing matrices (one for each subtractive primary color) which absorb dye in proportion to the density of a gelatin relief image. Successive placement of the dyed film matrices, one at a time, "transfers" each primary dye by physical contact from the matrix to a mordanted, gelatin-coated paper.

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