DK-60,DK-60a,DK-60b I'm old(ish) but not that old.

[darkroommike]

I need to scratch another itch and need help. I see reference in older Kodak material to Developer DK-60 but can only find formulas for DK-60A and DK-60b. I know that DK-60a was used, a lot, for commercial photofinishing and studios for roll film and sheet film, and even for "miniature films like 35mm and 828. And DK-60b was for aerial films and had sodium sulfate and benzotriazole added to DK-60a. So what's different in the original, my oldest Photo Lab Index only dates back to the 50's?

Any help appreciated.

 

[Craig]

I have a Kodak Reference Handbook from 1940 and it lists DK-60a, Replenisher DK-60aTR for deep tank hand processing and Replenisher DK-60aMR, for machine processing. The DK-60a and TR have formulas, the MR says available as a package, no formula given.

I also have Elementary Photographic Chemistry, published by Kodak in 1941 and it has the above, plus DK-60B. It's listed under "Formulas for Special Work", as a Kodalk Aero film developer. In a note it says for higher contrast use D-19 and for lower contrast use D-76.

So it looks like DK-60B was developed between 1940 and 41.

 

[darkroommike]

Thanks, that helps a lot, but was there a DK-60 or a D-60 before DK-60a, I realize Kodak was not very stringent in their naming conventions but the existence or both a DK-60a and a DK-60b begs the question. Maybe it never made it out of the lab?

 

[mshchem]

I looked at my old books, going back to 1941, Kodak provides only DK-60a formulas. I have a couple cans (c 1957) to make 3 1/2 gallons, I'm going to try it out someday

 

[Ian Grant]

Thanks, that helps a lot, but was there a DK-60 or a D-60 before DK-60a, I realize Kodak was not very stringent in their naming conventions but the existence or both a DK-60a and a DK-60b begs the question. Maybe it never made it out of the lab?

Probably, their are derivations from the Wellington Buffered Borax developer> Wellington was the manager of Kodak Ltd (UK) before setting up his own company, which later merged with Ilford.

Wellington Borax MQ Fine Grain Developer

Metol 2g
Sodium Sulphite (anhyd) 10g
Hydroquinone 2g
Borax 20g
Water to 1 litre

There is another version with less Metol.

Ian

 

[Craig]

Is Elon the same as metol? I see elon in the old Kodak books.

 

[MattKing]

Is Elon the same as metol? I see elon in the old Kodak books.

That is Kodak's trade name for metol.

 

[MattKing]

Thanks, that helps a lot, but was there a DK-60 or a D-60 before DK-60a, I realize Kodak was not very stringent in their naming conventions but the existence or both a DK-60a and a DK-60b begs the question. Maybe it never made it out of the lab?

Alternatively, they may have made DK-60a and DK-60b available at the same time.

 

[Ian Grant]

I'm not sure Kodak ever made DK60b commercially, it appears to be DK60a used 1+1 modified with the addition of Sodium Sulphate and Benzotriazole for high temperature "tropical" use. So possibly a USAF modification.

Ian

 

[Lachlan Young]

DK-50 and the genesis of DK-60 can be found in a 1934 patent from Harold D Russell (there's also a metaborate variant of D-76 in there) - who seems to have been heavily involved in the innovation/ patenting of metaborates at around that time & played a major role simultaneously in work on hardening fixes. He later seems to have been heavily involved in large capacity process machine design - and I'd suggest that I think you can see how the confluence of those interests led to DK-60a/b variants - and that Metaborate itself was clearly a solution to the problems of low emulsion hardness in the early 1930s when the activity levels/ characteristics of carbonate pH's were desired without the potential side-effects.