glen_h Posted January 21, 2020 Share Posted January 21, 2020 Does anyone know which process, presumably not in current use, uses CD-1? As well as I know, Kodachrome uses CD-2, but maybe older K processes used CD-1? -- glen Link to comment Share on other sites More sharing options...
kmac Posted January 21, 2020 Share Posted January 21, 2020 This may be of use .... "CD1 is used in Process ECP-2 for motion picture print film." Link .... Is possible to use the CD1 (color agent) in RA4 or C41 processes Link to comment Share on other sites More sharing options...
Alan Marcus Posted January 21, 2020 Share Posted January 21, 2020 In 1935 Kodak marketed Kodachrome. This color film consists of multiple coats of black & white film emulsions. It is initially developed to yield a negative black & white image. The film is then re-developed to create three positive black & white images. This is accomplished using three separate black & white developers containing a color developer. The color developers were C-16 (cyan), M-38 (magenta) and Y-54 (yellow). To my knowledge CD-1, CD-2 or CD-3 was not used. Due to the complexity of the Kodachrome process, a search for a simpler method was occurring. The answer was, incorporate incomplete dye into the film’s emulsion during manufacture. These were to be organic cyan, magenta, and yellow dye, in the Leuco (Greek white or hidden) state. Making such suitable dyes, missing the same ingredient is arduous. CD-1 was first used in the production of Afgacolor in 1936 by ORWO a subsidiary of Filmfabrik Wolfen under the umbrella of I.G. Farben. Using similar technology Kodak introduced a family of incorporated color film and paper products using similar chemistry. C-2 in color intermediate and color internegatives for motion picture applications and CD-3 and CD-4 in color negative and color positive films. Essentially, these incorporated color films contain Leuco cyan, magenta, and yellow dyes. During developing, a tuft of metallic silver is precipitated. Dissolved oxygen in the waters of the developer react with this silver. This is the catalyst that causes the CD (contains the missing ingredient) to unite with the Leuco dye; thus it blossoms into a full blown dye in proportion to the amount of silver laid down. 1 Link to comment Share on other sites More sharing options...
James G. Dainis Posted January 21, 2020 Share Posted January 21, 2020 I am absolutely amazed that chemists can come up with these procedures. It sounds more like alchemy than chemistry. 1 James G. Dainis Link to comment Share on other sites More sharing options...
glen_h Posted January 21, 2020 Author Share Posted January 21, 2020 In 1935 Kodak marketed Kodachrome. This color film consists of multiple coats of black & white film emulsions. It is initially developed to yield a negative black & white image. The film is then re-developed to create three positive black & white images. This is accomplished using three separate black & white developers containing a color developer. The color developers were C-16 (cyan), M-38 (magenta) and Y-54 (yellow). To my knowledge CD-1, CD-2 or CD-3 was not used. (snip) OK, it was my understanding, mostly analogous to later process chemistry, that C-16, M-38 and Y-54 were color couplers similar to those used with later films. Specifically, that a color developer was used along with them. Though that unlike the couplers used in other films which are hydrophobic, the Kodachrome couplers are water soluble. But that belief was based on very little evidence. (Evidence being in important discussions in the US Senate today.). Thanks though for the note about Agfacolor and CD-1. -- glen Link to comment Share on other sites More sharing options...
glen_h Posted January 21, 2020 Author Share Posted January 21, 2020 I now found a reference for CD-1 and Agfacolor, which also has much description of later processes, too: https://pdfs.semanticscholar.org/55a7/ae3d5cce0a5713e68e670d6460acb616da21.pdf which seems to have been generated by the National Archives regarding archival characteristics of color photographic materials. -- glen Link to comment Share on other sites More sharing options...
adycousins Posted December 23, 2022 Share Posted December 23, 2022 The Mannes and Godowsky Kodachrome patent of 1938 specifies CD-1 as the developing agent, the colour couplers they specified were: cyan: 2-phenyl-phenol yellow: acetoacetanilide magenta: 1-phenyl-3-methyl-5-pyrazolone these couplers produce poorer density when used with CD-3 or CD-4 The later K14 process used the newer couplers ( C-16 (cyan), M-38 (magenta) and Y-54 (yellow), and CD-4 for cyan, CD-6 for yellow and CD-3 for magenta (according tho the K14 processing manual) Link to comment Share on other sites More sharing options...
glen_h Posted December 30, 2022 Author Share Posted December 30, 2022 I made the Wikipedia pages for CD1 though 4. I didn't know about 6. Is there a CD-5? -- glen Link to comment Share on other sites More sharing options...
khheisler Posted January 29, 2023 Share Posted January 29, 2023 Kodachrome K-14 was an amazing process. Not many people had a good grasp on the process. Perhaps the most difficult process to keep in control. I spent 6 days a week analyzing all the constituents on this process. Coupler concentrations, re exposure filters, critical temperatures, and tribulation rates. Best 20 years of my life! 1 Link to comment Share on other sites More sharing options...
john_shriver Posted February 1, 2023 Share Posted February 1, 2023 CD-6 is in the patent for K-14 Kodachrome. US 3658,525. But maybe not by name. Some discussion here: https://www.photrio.com/forum/threads/kodachrome-patent.50878/ Link to comment Share on other sites More sharing options...
john_shriver Posted February 1, 2023 Share Posted February 1, 2023 CD-6 is in the Russian Wikipedia. https://ru.wikipedia.org/wiki/CD-6 Gives this as the CAS link: https://commonchemistry.cas.org/detail?cas_rn=50928-80-8 This page has structural diagram: https://chemicalportal.ru/compounds/cd-6/ Link to comment Share on other sites More sharing options...
rodeo_joe1 Posted February 1, 2023 Share Posted February 1, 2023 17 hours ago, john_shriver said: Gives this as the CAS link: https://commonchemistry.cas.org/detail?cas_rn=50928-80-8 That poor Sulphur atom is grossly outnumbered. I wonder if it would be missed? Link to comment Share on other sites More sharing options...
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