Ask A Scientist© Chemistry Archive

name         Bose
status       other
age          20s

Question -   
1. Is their any pigments which do not fade color in sunlight?
2. Does the self-luminous materials looses its property when exposed to
sun light?
3. Is their any non fading offset inks available in the market?

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Bose,

Though at first one would not think so, light is pretty energetic. 
Molecules can
degrade when exposed to light. If the molecules are colored, the degradation
results in either fading or a pronounced color change.

Most organic dyes will fade if exposed to light for a long enough time. The
day-glo material to which you refer is especially susceptible to fading. 
The only
colored substances that resist fading are inorganic -- like the solid
oil-suspended pigments found on artists' oil paints. As to inks: Look for 
those
compounded with solid pigments rather than dyes.

Regards,
ProfHoff
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1. There are many pigments that are not faded by sunlight. Examples are:
Copper phthalocyanene blue(s), that come in many shades. Iron oxides that
come in yellow, red, brown and black shades. Quinacridone based pigments
that are used in automotive red, and blue shades.

2. Without knowing what the material is that makes the material, I could not
say. But in general these are probably not going to be very light-fast.

3. I have not doubt that there are light-fast offset inks. However, offset
inks are used primarily in high quality color commercial printing where
quality color and printing properties, and not light-fastness, are the
primary properties the printer seeks.

Vince Calder
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