Photochromic Pigments

The Reversacol photochromic dye product range currently includes over 20 colours. There is also a range of single molecule photochromic greys, which offer the advantage of achieving a neutral colour without the need to mix several dyes.

Reversacols can be added to plastics, inks and coatings and there is a wide range of applications, including some of the following: ophthalmic photochromic lenses and sunglasses, security inks and coatings for passports and brand protection etc., perfumes and cosmetics packaging, optical switches, mobile phone covers, ski and sportswear, nail varnish, and even sun tanning dolls!
Reversacol photochromics can be combined with a wide range of special effect colourants such as light angle-dependent interference pigments, thermochromics, liquid crystals and permanent dyes to produce unusual photochromic effects or colour to colour effects.

Reversacols are not active in their crystalline powder form, but when combined with an appropriate solvent, ink or plastic, will readily change colour upon exposure to ultraviolet sources. Reversacols can be added to a variety of inks, paints, adhesives and plastics such as PE, PP, plasticised PVC, EVA, PVB, PUR and acrylics. The key for the dyes is to allow them the space to be able to twist in order to emit colour. Highly crystalline plastic materials, for example polyester, are not suitable. They are soluble in most organic solvents, but only sparingly soluble in water. Acidic systems should also be avoided.
For processing, as long as temperatures remain below 250