Digital BW, The Print

Op 28-12-2010 17:07, Peter schreef:
> I thought this was worthy of it's own thread.  Sandy King, a very
> accomplished carbon transfer printer, among other things, said the
> following to me about coating an inkjet print with gelatin:
>
> "Peter,
>
> One of the problems with gelatin solutions is that a large number of
> bubbles are created as you spread it on a paper. One way to get
> around this is to first spread the gelatin solution on the print, and
> then use a threaded coating rod, heated to 150F-170F, and roll it
> over the coating. The rod will push bubbles and debris to the side,
> leaving you with a perfectly even surface.
>
> I would suggest a gelatin solution of about 5%, and a formed rod that
> will leave a wet height coating of about .2 mm. Check out RD
> Specialities for formed coating rods.
>
> I use a very similar technique for sizing art papers for carbon
> transfer printing, the only difference is that I use a RD-200 rod
> that leaves a wet height coating of about .45 mm, and a 7% sizing
> solution.
>
> The idea of gelatin over the inkjet papers seems nicer, and safer,
> than other poly type coatings, which may be easier to apply but you
> can not be as sure as to their long term stability, whereas gelatin
> is for the ages."

The 2 and 45 mm seem a bit thick to me.

In combination with silver etc that hardens the gelatine. I wonder 
whether it is so nice without that effect: Funghi, bacteria, etc. One 
should look for the right hydrolysis degrees for the gelatines and PVA + 
possibly hardening methods after the application (formaldehyde?). 
Acrylic resins have a good reputation in art conservation. Paul's 
aliphatic polyurethanes were interesting too.



-- 
Met vriendelijke groeten,   Ernst

Try: http://tech.groups.yahoo.com/group/Wide_Inkjet_Printers/

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