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View Full Version : Developing agents in paper..........



Frank Lahorgue
15-Jan-2006, 11:27
I've seen references to Kodak including developing agents in Polymax Fine Art papers. I am nowing comparing samples of Ilford MGIV and Kentmere VC papers to replace the now discontinued Kodak paper. People claim that Ilford does NOT put developing agents in their emulsions, resulting in longer shelf life than the stuff from big yellow. Does anyone know if Kentmere papers also lack developing agents?

In other words, how do Kentmere papers stack up to Ilford in terms of shelf life?

Thanks

Jerry Flynn
15-Jan-2006, 15:10
I do not know about the current products, but a studio I worked at some years ago used a RoyalPrint machine that did not use developer, but an activator to activate the developing agent in the paper. It worked with all the then-available Kodak RC papers. It also worked with Ilfospeed (which we preferred for the Pearl finish), Ilford's RC paper of the day. It seems that if they were incorporating developing agents in their older generation RC papers, they may still do so now.

Donald Qualls
15-Jan-2006, 16:09
Modern Ilford and Kodak papers do incorporate developing agents, though most don't have enough to use in activator type processors -- tiny amounts, however, increase the paper speed and improve ability to control contrast (with multigrade). The bad news is, they also greatly reduce the storage life of the paper compared to the papers of, say, 40 years ago. These days, paper laid down in a freezer in the 1960s is more likely to be usable than what was put by in the 1990s.

FWIW, there are papers that don't incorporate developing agents -- IIRC, Foma and Forte papers (both of which are frequently rebranded) are free of developing agents; that means longer exposures, but it also means you can plan on paper that still works in 20 years if you freeze it.

lee\c
15-Jan-2006, 16:19
can't you immerse the paper in a solution of Sodium Carbonate and if the paper is developer incorporated won't it will start to develop?

leec

ronald moravec
15-Jan-2006, 16:57
Simon Gallery of Ilford swears to me there is not a trace of developing agent in their paper. A previous Ilford customer service rep said their was.

Reguardless, the current papers have a very limited shelf life and SOMETHING is causing it.

I am working a box of Polycontrast expired in 1969 right now. It was not even cold stored. It prints fine for most negs. Same with some Medalist, same age.

Whatever they are doing, they are not doing it to help me as the paper is not better. I read on one site, the added chemical allows immediate shipping with no aging. Then it a cost reduction plain and simple.

Sal Santamaura
15-Jan-2006, 18:23
The Kentmere data sheets available here:

http://www.kentmereusa.com/kt_main.php?p=ds

indicate developing agents are incorporated in Bromide and Fineprint. I haven't looked at the data sheets for Kentmere's other papers, and can't recall seeing anything on the subject in Ilford's paper data sheets.

Wayne
16-Jan-2006, 20:50
I'm curious what these agents would be. Anybody know?

Dave George
22-Mar-2006, 06:10
I am looking for a supplier of 8" and 10" bromide paper in a cassette for use on a typesetting system (Scantext). We use to use Agfa GS900 (for use with a cathray tube). If anyone knows of an alternative product/supplier I would be very interested.