From: Jean Burdett (jburdett@chariot.net.au)
Date: 12/31/00-11:16:32 PM Z
Happy New Millenium Everyone,
Thanks to Rob Fleming and other folk for the input. Since gum arabic will harden upon exposure to u.v. light,although without the speed or efficiency of gum dichromate ,there is no graet mystery concerning the instant cofee print. The exposured areas of te canvas, after development in water were brown, suggesting the coffee 'dye' had been drawn into the canvas fibres. My method of development is a bit agressive. I will float the canvas in future as suggested. I will try using more coffee and will repeat the proccess a multiple number of times so that the brown patches will become darker.
It was interesting that Rob noted that this method(i'm far too unsystematic at this point for it to be a system) would be safe for children. My initial interest was in finding ways of photographic printing that would be accessable for all people,including children and people with intelectual disabilities,or mental illness,hence my concern that all chemicals should be harmless when ingested. the problem with this and other non toxic methods, such as anthtypes, is the time required. This would be an issue for people with short attention span and/or short term memory loss and might raise logistical issues within a short work shop context. I'm open to suggestions.
I still don't really know what the story is with the prussian blue. When I develop(or in this case destroy) the print in water there is no evidence that the canvas has held the pigment. The image is only visable beforehand. A positive image is formed in the hardened gum. The exposed areas are considerably lighter than the unexposed areas, suggesting that the the pigment is fading in sunlight. according to http://www.handprint.com , Windsor and Newton Prussian Blue is reasonably lightsafe (3.5 out of 5) but can fade when in contact with an alkaline substance. Is gum arabic alkaline? I am testing to see if the image fades in sunlight. I'm checking to see if the wet pigment fades on its own when exposed to u.v.
By the way I'm not Jean I just borrow her address. I should have my own adress soon. Until then , I'm not bothered by being inadvertantly called Jean,
Birdie
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