Re: Chrome alum sizing

I recently did some gumovers with 1% chrome alum and 3% gelatin in the sizing.
My experience was mixed. First, I found I had to be very careful about evenly
coating the paper, because the sizing has a bluish cast that is quite
noticeable in any drips and runs. Secondly, it caused MUCH worse dichromate
staining, which made it hard to judge how far into the highlights I was
actually getting some pigment. Fortunately, the staining was easily removed
with potassium metabisulfite.

Clay
Quoting gdimase@hotmail.com:

> Hi,
> I didn't get any feed back so I went back to the list files since 1996 and
> did not find too much on chrome alum ratio's sizing.
> Just sideline comments.
> As a conclusion it sounds that Jill is right to add a 2 per 1000, somewhere
> else I found other people working up to 5 per 1000 and others went down to 1
> per 1000.
> Usually people don't like it when working with gum bichromate (increasing
> chrome component and staining) and truly the sized paper doesn't look smooth
> and sometimes even dirty.
> It looks that PVA has a better future against this old chemical mainly on
> large prints.
> Giovanni
>
Received on Mon Aug 22 09:58:48 2005