oil-print-glyoxal??

Since some time I am working with oil-printing; it is much easier to
handle compared to bromoil (if one has anyway some big negatives for
cyano or gum...), but what about hardening.
In principle it is the same way of working compared to gum. Some
gelatine layers , a dichromate etc.; but no glyoxal,formaldehyde or
chromealum after sizing (one needs the swelling of the gelatine, so a
hardening at that stage cannot be done).
After the inking, I am not sure if the gelatine at the highlights is
protected against bacterie-growth, there is little or no ink at the
highlight-areas. I could not find any info in the books.
Any idea??
Cheers,
Henk

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H e n k  T h i j s  -  P h o t o g r a p h y
photography     http://www.thijs-foto.com
member of F68   http://www.f68.nl
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