U of S | Mailing List Archive | alt-photo-process-l | Re: gum preservatves

Re: gum preservatves

I guess most people use thymol nowadays.

Just for the record: I opted for sodium benzoate - because it was cheaper
/ easier to obtain than thymol. I use it generously; about 1g per 100g of
gum (Probably overkill. But it's easier to weight 1g in place of dealing
with fractions...) and it preserves the gum pretty nicely with no adverse
effect to my printing. (No problems even after 2 years.) Will reduce the
amnt. (tenfolds!) to 1g per 1000g of gum in the next batch (soon).


4 Eylül 2008, Perşembe, 4:26 am tarihinde, Judy Seigel yazmış:
> Long ago (practically at the dawn of time) the list ran a thread on
> preservatives for gum. In those days I still had some formaldehyde and
> mentioned that one or two drops in a 2 to 4 ounce dropper bottle of gum
> preserved it, as far as I could tell, permanently.
> I bought some of the other materials mentioned, but didn't test them
> rigorously -- tho I mention for those whom it may concern that they
> included salicylic acid and 15% thymol in  methyl alcohol. I don't think I
> got but it was mentioned, some form of lavender, which can give a lovely
> aroma, if nothing else.
> ...