Archived posting to the Leica Users Group, 2002/02/17
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Marc James Small wrote: > > At 07:55 PM 2/17/02 -0400, Robert G. Stevens wrote: > >Up here in Canada Xtol cost $14 CAD ($8.75 USD) for five litres. It seems > >pretty cheap and unless your hobby is photographic chemistry, it doesn't > >look like their would be much savings in mixing it yourself. > > Down here in the US, XTOL is not generally available outside of larger > cities, as most photo stores refuse to carry it. Thus, the interest in > developing a self-mixing formula. > > Marc > > msmall@roanoke.infi.net FAX: +276/343-7315 > Cha robh bąs fir gun ghrąs fir! > > -- > To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html The Xtol patent is USP 5,756,271 May 26, 1998 & USP 5,702,875. This is the formula for a powder version of the formula as disclosed in the patent: Part A Sodium Sulfite 10 grams Diethylenetriaminepenta-acetic acid, penta sodium salt 1 gram Sodium Metaborate (8 mol) 4 grams 4-Hydroxymethyl-4-methyl-1-penyl-3-pyrazolidone 0.2 grams Part B Sodium Sulfite 75 grams Sodium Metabisulfite 3.5 grams Sodium isoascorbate 12 grams Part A dissolved in 850 ml of water at room temperature having a pH of 10-19 +/1 0.05 Part B then dissolved in the solution at room temperature, and water was added to 1 liter. Mark Rabiner Portland, Oregon USA http://www.markrabiner.com - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html