UV reactive materials
photochromic pigments from mindsets
UV reactive materials, which initially have an off-white appearance, change to bright colors when exposed to UV rays (sunlight or a UV lamp) and revert to their original pale color when away from UV light. The basis for these materials are photochromic pigments which can be mixed with an acrylic base and then applied as normal paint. The more dilute the pigment, the less dramatic the color change.
acrylic base to orange photochromic pigment ratio tests ran by a student of the Aix-en-Provence (France) Art School
Besides pigments, which can be used to make color-changing paints, photochromic materials are also available in the shapes of sewing and embroidering thread, plastic goods such as beads and buttons, and nail polish. Naturally it’s also possible to produce photochromic fabrics, but I haven’t been able to find them as raw materials in retail shops.
photochromic thread and beads (indoors and outdoors)
What is it exactly?
According to Wikipedia:
Photochromism does not have a rigorous definition, but is usually used to describe compounds that undergo a reversible photochemical reaction where an absorption band in the visible part of the electromagnetic spectrum changes dramatically in strength or wavelength. In many cases, an absorbance band is present in only one form. The degree of change required for a photochemical reaction to be dubbed “photochromic” is that which appears dramatic by eye, but in essence there is no dividing line between photochromic reactions and other photochemistry.
Suppliers
:: Mindsets (UK): photochromic pigments and sewing thread
:: Solar Active (USA): UV reactive sewing and embroidering thread, plastic goods (beads, buttons, etc.), nail polish
Share your knowledge
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Thanks for sharing, this is a fantastic blog. Much obliged.
To whom it may concern,
My name is Janice, from Johnson & Johnson.
I would like to ask if you have any UV reactive pigments which has off-white color in the absence of UV, turns to vivid color in the presence of UV. And upon removal of UV, the vivid color still remain for a while until turns back to the basis off-white color.
Looking forward to your reply.
Janice Nguyen
Johnson & Johnson Asia Pacific
Email: jnguyen6@its.jnj.com
Tel: (+65) 6720 6323
Hi Janice. That’s exactly how UV chromic (aka photochromic) pigments behave: they start off-white, immediately change to vivid colors when exposed to UV, and upon removal of the UV source slowly turn back to off-white. You can find the raw pigments at this online store:
http://www.mindsetsonline.co.uk/index.php?cPath=418_627_465&osCsid=j19d023fbee8l3uktuh53ts733
Hi! I make buttons (like the kind you pin on your shirt or bookbag) and I’m trying to figure out where to find UV reactive paper. I’d like to experiment with both UV reactive paper and UV reactive ink, however I’m unsure where to find either. Is it possible to use UV reactive ink in my normal computer printer? Any help would be greatly appreciated :) Thank you so much!
kristine.volovsek@gmail.com
Hi Kristine. I’ve never seen UV reactive paper for sale, but in theory you could make your own by painting a piece of paper with UV reactive paint.
The only source I know of that sells photochromic pigments directly to the public is Mindsets: http://www.mindsetsonline.co.uk/index.php?cPath=418_627_465
I doubt you could use it on a computer printer since it’s probably too thick and would clog the cartridge. But if you don’t mind risking damaging a cartridge it’s worthwhile trying. You can get the pigments from Mindsets and mix them with a thin base such as an airbrush medium.
I imagine you’re referring to the kind that changes color (photochromic), but there are other UV reactive materials that exhibit luminescence: http://en.wikipedia.org/wiki/Luminous_paint
There are some cool powdered photochromic and thermochromic pigments at solarcolordust.com
Thanks for sharing!
SolarActive manufactures and develops different processes and systems that all change colors instantly when exposed in the sunight. If you have an idea and want us to work out a color change system just contact us direct
with any questions. solaractive@aol.com
Has somebody made sunscreen with photochromic ink mixed in in such a way that your kids change to funny colors when it is time to reapply?
I would love to buy that product. Or to tinker with the idea.
Thanks,
Arturo
I have not seen thermochromic pigments used in sunscreen and I’m not sure whether they’re safe to apply to children’s skin directly. But one of the activities done with thermochromic beads (plastic beads infused with thermochromic pigments) is to test UV blockage of sunscreens. If the pigments are indeed safe for applying directly on the skin, that would be a very interesting product!
Very interesting. There are processes and systems that change color instantly when exposed to sunlight. Are there also processes and systems that instantly change color back when no longer exposed to sunlight?