OZOBROME, OIL Oil ozobrome is a modification of bromoil. A bromide print is treated in such a manner that the altered image will retain greasy ink while the unchanged portions will repel it. A bromide print is bleached in the following bath :— Ozobrome pigmenting solution . . . I oz. 3o ccsChrome alum acid bath 5 „ 150 „ Sodium chloride (salt) I- „ 17 g.
Water . • 4 •, 120 ccs.
The bleached print is rinsed for a few seconds and transferred to u fixing bath of " hypo " 3 oz., and water so oz., where it should remain for five to six minutes. After washing for five minutes, the print may be inked up, but it is better to allow it to dry and then resoak for five to ten minutes in water at 65° to 7o° F. (about i8 to C.).
Oil Transfer this process the resulting image will be reversed in regard to right and left ; therefore, in enlarging, the negative should be reversed in the lantern. A sheet of ozobrome transfer paper is immersed in the bleaching bath specified above, whilst the bromide print is soaking in water. The
transfer paper, saturated with the bleaching solution, is placed face upwards on a sheet of glass, and the wet bromide print carefully laid down upon it and squeegeed into contact. The bleaching takes from io to 45 minutes to com plete, the progress of the action being easily observable by holding the adhering papers in front of a strong light. When bleached, the papers are separated and washed for about ten minutes until all yellow coloration has dis appeared. The transfer paper, carrying a copy of the image, should be hung up to dry and the bromide print redeveloped. When dry the impressed transfer paper is soaked for zo to 3o seconds in cold water, and after removing the superfluous water it is ready to ink up. The bromide print is available for further transfers.