From: Sandy King (sanking@clemson.edu)
Date: 07/26/03-11:43:30 AM Z
Judy Seigel wrote:
>On Sat, 26 Jul 2003, Judy Seigel wrote:
>>.... I can attest that there are brands that do not not
>> not NOT work.... Generally these are not the major international brands
>> (Winsor Newton, Rowney, etc., and now Daniel Smith) tho there are
>...etc.
>
>
>Reading now at about the 125 mark I see I should clarify what I mean by
>"brands that do not work" ... That is, they will not clear, no matter what
>else you do or don't do they will NOT NOT NOT clear.
>
>I suspect, tho I cannot prove (nor do I need to) that there are some
>dispersal or similar agents added to these brands, perhaps to make the
>cheaper ingredients flow. When I tried adding a pure dispersal agent to
>gum emulsion, the effect was similar.
>
>J.
I agree with Judy on this. As a carbon printer I have tested
hundreds of different pigments from a variety of sources, from tube
watercolors to automotive supply pigments to Createx to aqueous
dispersions available at home supply stores. This experience tells me
for a fact that some pigments, or their dispersal agents, harden
gelatin and leave a high fog density that makes clean highlights
impossible. If this happens with gelatin I strongly suspect it would
also happen with gum, and that would result in a stain, an/or make
the print difficult to clear.
Sandy King
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