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What is Photochromatism or Photochromism of dyes? |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| Photochromism is the reversible transformation of a chemical species between two forms by the absorption of electromagnetic radiation, where the two forms have different absorption spectra.This can be described as a reversible change of color upon exposure to light This property is a boon for scientists doing research on intelligent textiles where they are making use of this property to store data on the surface of textile fabrics and polymer sheets. Whereas the same property of some reactive dyes is a bane for textile processors. The change in shade after dyeing creates unwanted problems in dyeing. An optical recording medium contains, on a base, one or more dyes and a polymer which forms liquid-crystalline phases. The information is written into the uniformly oriented liquid-crystalline polymer layer, for example by means of a laser. During this procedure, the polymer heats up locally to above a phase transition temperature. By cooling, the resulting change is frozen in the glass state. The information can be erased by applying an electric field and/or heating. The recording material permits high-contrast storage and possesses high sensitivity, good resolution and excellent stability. There are other chromatic properties called electrochromatism and thermochromatism of dyes that are affected by electric field and heat respectively. PHOTOCHROMIC
Photochromic colors are plastisol-based inks, which are off-white when not
exposed to UV radiation. It gains colour when exposed to Sun light / UV
light. The color change is "reversible," i.e., the color will fade again
and appear colour less upon removal from UV light / sun light exposure.
These inks are available in various colors. See our colour availability
chart for a complete list of available colors.
The uses of Americos Photochromic colors are :
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