In general

FOMACITRO is a liquid concentrate of a citric acid-based stop bath – a recommendable complement in processing of negative/positive black-and-white photomaterials both for amateur and professional use. FOMACITRO is completely odourless.

Packaging

FOMACITRO is available in PE-bottles of 250 ml.

Yield

The amount of photomaterial processed depends on type and dilution of developer used. A colour change of stop bath working solution from yellow-orange to blue-green signals that the bath is exhausted and should be changed for a fresh one.

Preparation of working solution

For use, the concentrate is diluted with water in the ratio of 1 + 19.

Use
When the exact stopping of development is needed (e.g. during extremely rapid development), the photomaterial is put from the developer directly into the prepared stop bath. The alkaline developer in swollen gelatine is being neutralized, looses its reduction ability, and the development is immediately interrupted. The incorporation of a stop bath into processing procedure prevents fixer to be contamined by developer rests so that its life will be prolonged.

Stopping time at 20 oC

– 10 to 20 seconds for films and papers on the RC paper base – 20 to 30 seconds for papers on a baryta paper base