Home >> Textile Processing Articles-1
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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 :
- On garment to create novel products and promotional items like
T-shirts
- On fabric/garment to print company logo / brand name to prevent
duplication
- On garment which are used for party wear
- Thermometers and temperature indicators
- Security printing
- Food industry to indicate temperature of packaged food
| 