Abstract: An original-treating agent to be used in the process for the diazo-type multi-color reproduction by which portions of a sensitive paper corresponding to preselected portions of an original can be colored selectively in different hues.

Abstract: This invention relates to a process for diazotype multicolor reproduction using an improved photosensitive material having a continuous thermoplastic resin pre-coated layer.

Abstract: A process for diazo-type multi-color reproduction by which portions of a sensitive paper corresponding to predetermined portions of an original can be colored selectively to different hues by disposing a layer of thermotransferable coupler between an original and diazophotosensitive paper followed by exposure to light and heating of the assembly. The layer of thermotransferable coupler is not applied to the entire image area of the original and the thermotransferable coupler is faster in coupling rate with the diazonium salt under the development conditions than the basic color coupler of the photosensitive paper or developing solution.

Abstract: An improved process for diazo-type multicolor reproduction comprisingA. exposing to light an assembly comprisingI. an original comprising opaque image areas and complementary non-image areas which transmit light,Ii. a photosensitive layer containing at least one photosensitive diazonium salt (c), an azo coupler (b) and a substantially non-thermovolatile acidic substance (d), the acidic substance (d) being present in an amount of at least 5 mols per mol of the diazonium salt (c), andIii.