Sprint Block Stop Bath, Vanilla Scented Indicator Stop Bath for Black & White Films and Papers, 4 Liter

Safely and effectively stops development and adjusts the pH of b&w films and prints without unpleasant side-effects. An indicator color signals exhaustion in b&w printing solutions. In conventional stop baths, the acid ingredient which stops development is hazardous and unpleasant to use, and can damage prints. Acid can break down print sizing which normally protects fibers from fixer thiosulfate contamination, a major cause of deterioration. Plain water stop baths eliminate the side-effects of acid, but do not stop development as effectively, and can cause stains and emulsion swelling and reticulation. BLOCK is an acid solution, but the acids are buffered to minimize the side-effects. Buffering protects print fibers BLOCK is the basic stop bath for all SPRINT SYSTEM processes. When used with other SPRINT b&w printing products, it signals the exhaustion of all baths simultaneously. Always use BLOCK before fixing with alum hardener to provide the correct acid value. One liter of concentrate will make 10 liters of working solution, enough for 600 8x10 fiber prints or 900 8x10 resin-coated prints or 600 rolls of film. * * * * * * * * Due to hazardous material regulations, this item can only be shipped by UPS GROUND, (no air freight)