BLOCK Stop Bath

$7.53$66.32

BLOCK is the basic stop bath for all SPRINT SYSTEMS processes. If you are using Record Speed Fixer with Record Alum Hardening Converter, always use BLOCK Stop Bath before fixing so as to provide the correct acid value.

One liter of BLOCK Stop Bath concentrate will make 10 liters of working solution.

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SKU: SB000_W Category:

Description

BLOCK Stop Bath

In conventional stop baths, the acid ingredient which stops development is hazardous, 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, emulsion swelling and reticulation.

BLOCK is an acid solution, but the acids are buffered to minimize side-effects. Buffering protects print fibers for greater permanence, reduces emulsion swelling, staining, reticulation and eliminates odors. BLOCK will also prevent carbonate gas ruptures of films (pinholes) when used as directed.

BLOCK is the basic stop bath for all SPRINT™ SYSTEMS processes. Always use BLOCK Stop Bath before fixing with RECORD Alum Hardening Converter to provide the correct acid value.

One liter of BLOCK Stop Bath concentrate will make 10 liters of working solution, enough to process (600) 8×10 fiber prints or (900) 8×10 resin-coated prints or (600) rolls of 35mm, 36 exposure film.

How to Mix

Dilute BLOCK concentrate 1:9 with water to make the desired volume of working solution.

100mlBLOCK Stop Bath Concentrate
+900ml Water
=1000mlBLOCK Stop Bath Working Solution

Stop Bath Procedure

Use BLOCK Stop Bath working solution at the same temperature as the developer solution. Never subject film to sudden temperature changes in processing; reticulation, or an apparent increase in graininess may be the result.

For Films: Immerse for at least 1 Minute with continuous agitation.
For Prints: Immerse for at least 5 Seconds with continuous agitation.

Hardening Stop Bath

BLOCK Stop Bath may be converted into a hardening stop bath for sepia toning, or to replace hardening in the fixer if sulfur dioxide vapors must be minimized. Substitute the following converted working solution for the normal stop bath and immerse films or prints for 3-6 minutes with agitation.

40mlBLOCK Stop Bath Concentrate
60ml ARCHIVE Fixer Remover Concentrate
900mlWater
+30mlRECORD Alum Hardening Converter Concentrate
=1030mlHardening Stop Bath Working Solution

When mixing hardening stop bath, the order of mixing is important. The Archive and Block concentrates may be mixed with water in any convenient order, but the Record Alum Hardener Concentrate must be added last.

 

Additional information

Weight N/A
Dimensions N/A

Capacity & Exhaustion

Capacity

One liter of BLOCK Stop Bath working solution will process at least (60) 8×10 fiber prints or (90) 8×10 resin-coated prints or the equivalent of (60) rolls of 35mm, 36 exposure film.

Exhaustion Indicator

BLOCK Stop Bath working solution changes color from yellow to lavender as it approaches exhaustion in B&W printing.

When using QUICK SILVER Print Developer, BLOCK Stop Bath and RECORD Speed Fixer mixed in equal volumes, the lavender color of BLOCK will signal the simultaneous exhaustion of all three solutions.

 

Shelf Life

Shelf Life

Stored as concentrate or working solution, with or without air in the container, BLOCK Stop Bath has a shelf life of at least 2 years.

FAQs

Do I have to use Stop Bath?

No but, stop bath is cheap and avoids problems from developer carrying over into fixer. Staining and reticulation are prevented, and the life of the (more expensive) fixer is extended.