Precipitates on Pt prints
Richard Sullivan (richsul@roadrunner.com)
Sat, 21 Sep 1996 12:32:29 -0600
Tom Hawkins says:
>As my pt/pd prints dry, a dusty white precipitate forms on the surface of
the
>paper. Some of the deposit can be removed by lightly wiping the print, more
>can be removed by dabbing with a gum eraser, and neither of these methods is
>satisfactory since they damage the print surface (though almost
imperceptibly)
>and don't solve the problem (some of the precipitate appears tohave formed
just
>below the top layer of paper fibers).
You might try a final bath of edta after the hypoclear. Or.. Tween 20... or
Joy detergent. (it used to be one of the purest detergents around, that is
back in the 60's, no telling what it is now. 3M once recommended it for
cleaning a $6000.00 defraction grating when I worked at Spectrolab in the 60's.
Bostick & Sullivan
1541 Center Dr.
Santa Fe, New Mexico
87505