Cyanotypes on Glazed Ceramic Tiles

I was looking for some advice on sizing ceramic tiles for cyanotypes and came across Photo Engineer´s APUG recipe:

10 g 250 BI photo grade gelatin
90 g Distilled Water at RT

Mix and gradually raise to 40 deg C.

Add 5 ml of 10% Chrome Alum solution.

Add a suitable wetting agent if needed if tests show problems coating.

Spread on clean, grease free tile at about 10 - 15 ml / foot square.

Allow to cure for about 1 week.

Has anyone tried this successfully? Is it possible to do the same using some kind of varnish instead?

For those interested, i tried poliurethane varnish without any success.

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Originally Posted by Zarraboy

For those interested, i tried poliurethane varnish without any success.

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Do you mean that you tried to prep a surface of poly finish using the gelatin mix without success?

Did you try the gelatin on tiles?

I'm curious. It seems that cyanotype on tile would make a very good base for decorations.

Hi, i tried to prep a glazed ceramic tile with poliurethane varnish but there is no way the cyanotype solution will be absorbed by that. I will now try the formula above. I havent tried it yet because i do not have photographic grade gelatin available.

Making the cyanotype on an unglazed tile and then glazing it might work better.

Quote:

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Originally Posted by Zarraboy

Hi, i tried to prep a glazed ceramic tile with poliurethane varnish but there is no way the cyanotype solution will be absorbed by that. I will now try the formula above. I havent tried it yet because i do not have photographic grade gelatin available.

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Just use knox gelatin that you get at the grocery store. It is suitable for subbing. I just coated a glass plate with a knox/gloxal layer and it is perfectly transparent. Good luck!

Nicholas, how will the solution stick to the unglazed tile? Alex, transparency is not the issue, is the cyanotype solution uniformely absorbed by the gelatin?

Perhaps I should have put references with my previous post.

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[...]Once the glass is perfect, and dry, you need to pour a warm gelatin, with the Gloxal added to it, over its warmed surface.

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Christopher James The book of Alternative Photographic Processes

And just to be sure I just did a test on a scrap piece of glass with cyanotype chemistry and it came out great.

I scrub the heck out of my glass plates with 'Bar Keepers friend" until I get even sheeting. Once they air dry I warm them with a hair dryer and pour apply 15ml of a 40% glyoxal solution to 250ml gelatin (6.5 grams knox to 250ml cold. Swell for 15mins the bring up to 140f for a few mins).

To improve the prints I'd recommend 2 coats of cyanotype chemistry before exposing.

EDIT: Also I have never found a need in my own experiments for photo-grade gelatin in subbing layer. Perhaps PE can give more information on this

Recipe looks good! I will try that on tiles. Thank you!

Alex, where do i find Glyoxal? Is there a more generic name for it?