We've all seen people wearing those funny glasses which have normal-looking lenses until the sun shines big time, at which point they tint black. Make tattoo ink that follows the same principle, and hey presto you've a tattoo that comes out in the sun.
-- -alx, Aug 02 2001

Source for photochromic inks http://www.colorchange.com.tw/
Originally provided by angel. [Dog Ed, Aug 02 2001]

Source for photochromic inks http://www.colorchange.com.tw/
Originally provided by angel. [Dog Ed, Oct 04 2004]

An acquaintance of a friend of a friend whose main pastime was taking lots of ecstacy and dancing in Techno clubs (apparently) had "f**ked up" tattooed across his forehead in ink which only showed up under UV lights. By day he was a respectable office worker. Sounds highly unlikely though.
-- stupop, Aug 02 2001


I've seen a UV tattoo of a barcode on someone's arm.
-- -alx, Aug 02 2001


I've heard that in Korean women's prisons, they tattoo a rose on their faces using chicken's blood. (???) You can't see it normally, but then whenever they blush or tan or whatever, you can see it and you know they've been in prison.
-- Karomon, Aug 02 2001


There are a dozen or so kinds of photochromic inks available for printing and silkscreening; I don't know if any are officially approved for tattooing. I'll pass along a link given me by angel, <self-promotion> or you could look on the Materials for Techno-Wizards section of An Halfbaker's Helper.</self-promotion>
-- Dog Ed, Aug 02 2001


How about a semi-permanent ink that slowly fades over time - say 6 mos. to 3 years. It could be made with vegetable inks or some sort of collagen or hylauronic acid that would be naturally flushed out by body. That way you could get a tatoo and not have to worry about the permanancy.
-- IndoCanuck, Aug 03 2001


[PeterSealy] Because it would look cool.
-- -alx, Aug 03 2001


I've got a Photocromatic tatoo. It's a f**ked tribal symbol. I had it put on my neck about three years ago at Electric Head Tatoo in Iowa City Iowa. Aside from a little abnomal itching for a few months I have had no problems. There isn't much info out there about these kind of tatoos and you always hear horro stories. All i'm saying is when I go clubing I look Like a freak..
-- Utharn, Oct 06 2001


How about this one, you know the stickers that you can get at tanning beds? Now there is a product that your can use to draw a design in your skin, then expose yourself to the sun, wash off the stuff and presto! a temporary image in your skin! I've seen people writing on drunken friends during "Spring Break" the friends dont know till the next day and they're marked for a while!! it's at www.doopiestuff.com
-- clw, Jan 21 2002



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