Gasparcolor
A three colour subtractive reversal print stock. It appeared in 1934 and was the first three layer colour film that could be processed with minor modifications to contemporary laboratory techniques. It did not require toning, colour development or use of dyes during processing. It used pre-dyed emulsions and dye bleaching.
An illustrated description of the way the processed worked is available below as a pdf file.
Please feel free to contact me if the description is not clear or you have further questions.
