[Leica] Re: wetting agents

["Michael D. Turner" <mike@lcl-imaging.com>]

Jim Brick wrote:

> At 02:17 PM 5/23/99 -0500, you wrote:
> >
> >The main thing to keep in mind is to never let the wetting agents dry onto
> >the reels, get it washed off while its still wet.
> >
> >gck
>
> This is the basic problem. It was invented to "stick" to the surface of
> stuff (dishes, film, and unfortunately reels) so that the "molecular layer"
> will act like a new surface and water will "sheet" off, instead of beading
> up. Its intended purpose is to "not" wash off. Which it doesn't.
>
> It is very possible that a "hot" water wash will break down the surface
> molecular bond and release the agent, but is sure seems simpler to "not"
> have to do this. Simply dump your film into a tupperware container sans
> reels like Tina and Jobo recommend. And then a "normal" rinse of reels will
> suffice.
>
> JMHO
>
> Jim

I have never researched the chemistry involved here, but I remember the
manufacturer's recommendation for my Wing-Lynch processor: both Photo-Flo and
E-6 and C-41 stabilizers were detrimental to the plastic components of the
processor. That suggested to me that both formaldehyde and the wetting agents
used in Photo_flo and the color process stabilizers attacked the polymer
chains in these plastic components which would eventually deteriorate them.
Period. So film should be soaked in these postprocess chemicals _outside_ the
processor to avoid this problem, and reels (even stainless ones) should be
washed thoroughly before re-use to avoid contamination of first developers.
Makes sense.

My advice: If you use stainless reels, you may dump them film and all into
Photo-Flo or C-41 stabilizer or E-6 final rinse. Wash them thoroughly before
reloading them. If you use plastic reels, take the film off them, never let
them contact any wetting agent or film stabilizer. And, of course, always wash
them thoroughly before reloading.

- -Mike