SB-4 Tropical Hardener Bath

When processing at high temperatures a mildly alkaline, buffered borax developer is recommended. Alkali-free developers of the amidol type or one of the mildly alkaline fine grain developers such as Kodak D-23 are preferable to those with normal alkali content. Additionally, a pre-hardening bath such as Kodak SB-4 Tropical Hardener Bath or a specially formulated tropical developer may be used. 

Stop Bath for Tropical Development Films should be immersed for three minutes in either Kodak SB-4 Tropical Hardener Bath or Kodak SB-5 Nonswelling Acid Rinse Bath after development and before fixation. Agitate the negative in the stop bath frequently. 

NOTE 1 When development is completed, rinse the film in water for 1 or 2 seconds only and then immerse in Kodak SB-4 Tropical Hardener Bath for 3 minutes (omit the water rinse if the film tends to soften). Then fix for at least 10 minutes in an acid-hardening fixing bath, such as Kodak F-5 Hardening Fixer, and wash for 10 minutes in water at not over 95F/35C. 

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