Can Boric acid be used for Borax?

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markbau
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Can Boric acid be used for Borax?

Post by markbau » Fri Jun 21, 2019 6:10 am

I just ordered some Borax for use in mixing up D76. What turned up was "Boric Acid" are they the same thing? An internet search does not make it clear if they can be substituted. The latest cookbook mentions both but does not say if Boric acid can be substituted for Borax.

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sanchell
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Re: Can Boric acid be used for Borax?

Post by sanchell » Sat Jun 22, 2019 9:13 pm

Borax and Boric acid are not the same things. Borax is an alkali and in common grades is used in washing powder (20 Mule Team Borax). Boric acid is an ... acid. It is often used in roach poison.

WARNING: Do not wash your clothes in boric acid! Keep out of reach of cockroaches.

Boric acid is also used in some film developing formulas. Bill Troop is including several formulas in the 2nd Edition of the Film Developing Cookbook, which I am almost through editing.

Boric acid is extremely difficult to dissolve. Borax dissolves like soap.
Do it in the Dark,



Steve Anchell

tim.bowman
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Re: Can Boric acid be used for Borax?

Post by tim.bowman » Mon Jun 24, 2019 6:12 am

Bill Troop and I are including several formulas in the 2nd Edition of the Film Developing Cookbook, which is within a few weeks of going to the publisher.
Very glad to hear that little tidbit!

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sanchell
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Re: Can Boric acid be used for Borax?

Post by sanchell » Mon Jun 24, 2019 10:21 am

I didn't have a copy of the Cookbook in front of me when I previously responded.

Page 201 of the 4th ed.

Borax
Uses: As a mild alkali accelerator in fine-grain developers and those of low activity; ...

Page 194
Acid, Boric
Uses: As a buffer with borax to maintain a stable pH, even when the developer is greatly diluted.

Errata: According to the Cookbook it is used as a roach poison, not a rat poison. Keep it out of reach of any roaches in your darkroom.
Do it in the Dark,



Steve Anchell

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