Archived posting to the Leica Users Group, 1999/02/18
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Could very well be. But if you beat it around too much, it foams-up like detergent or soap. I know that a single drop of "clear" Ivory liquid (detergent I suppose), to a couple of liters of water, can be used in an emergency. So photoflo, to me, acts "soapy". Even if it isn't. thanks Alexey, Jim At 03:46 PM 2/18/99 +0000, you wrote: >Jim Brick wrote: > >> Photoflo works because it is a soapy solution with a pH above 7. > >So far as I can tell Photoflo is simply nonionic detergent - NP40 or >Triton X-100 or Tween20. It works by decreasing the wash water's >surface tension, reducing droplet formation on the film surface. > >If I'm correct about this, Photoflo is neither soapy (soaps are IONIC >detergents), nor does it affect pH. If it did change pH it would do so >by containing a buffer, and this would, I think, tend to INCREASE >spotting because buffers generally are salts. > >For several years I've used NP40 instead of Photoflo (I use an outdated >lab stock that I no longer trust for my biochemical work). Seems to work >perfectly. >.......................................................................... >Alexey Merz | URL: http://www.webcom.com/alexey | email: alexey@webcom.com > | PGP public key: http://pgp5.ai.mit.edu/ | voice:503/494-6840 >