> One problem I have been struggling with is staining of the paper I use
> (types vary) by my sizing. I use gelatin, dipping the paper in the
> sizing once, drying, then dipping it in gelatin with formaldehyde to
> harden the sizing.
>
When you say "staining" you mean the paper itself is staining, or the
pigment stains the paper when you expose & develop?
Also, is it a dichromate stain or a pigment stain?
What % and what kind gelatine are you using? Some gelatines tend to hold
pigment. Are you keeping the gelatine quite hot so it doesn't get on too
thick?
Are you squeegeeing the paper, or squeezing it between a plastic rod
and tray edge when taking it out so gelatine isn't too thick?
How much formaldehyde in the gelatine?
A lot of formaldehyde can also harden so much it outgasses & causes
staining. Have you tried glyoxal?
> I can see the areas that are going to give me problems when the paper is
> drying. I have tried brushing the paper while wet with sizing to make
> sure the gelatin is distributed evenly. Perhaps the areas that refuse
> to cooperate are weaknesses in the papers.
Although you don't give enough specifics to make a good guess, it sounds
like some areas of the paper are not getting gelatined -- they had greasy
finger prints? There were air bubbles in the gelatine? The paper didn't
soak long enough?
I've gelatine sized about 30 different papers & never seen problem you
describe or anything remotely like except Arches Aquarelle, which I never
could get to work for gum.
There are, BTW (do I get fined for saying this), detailed details of
sizing procedure you know where......
Hurriedly,
Judy