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Colors When Faded
Name: Ariana
Status: student
Grade: 4-5
Location: OK
Country: N/A
Date: December 2006
Question:
Where does the color go when it fades away?
Replies:
The difference between a normal color and a faded color is,
perceptually, called saturation. Physically, saturation is based upon
wavelength (or colormetric) purity. Basically a faded color reflects a
wider range of visible wavelengths than a normal (strong or saturated)
color. Color on surfaces comes from the selective reflection of some
wavelength range by paints or dyes or pigments (man-made or natural).
When a color fades the paint or dye or pigment has changed so that it
reflects a wider range of wavelengths than it did before it faded.
Michael S. Loop
Color in cloth and paper results when the molecules of the dyes
and/or pigments have special sizes and shapes that let it absorb
light in different ways. Some dyes and/or pigments are changed by
oxygen and / or light itself so that those special sizes and shapes
are changed in such a way that they can no longer absorb the light
in the special ways. That, very simply, is what causes fading.
Vince Calder
Color comes from the way light reacts with the structure of the material
(object) itself, things like particle size or the type of chemical bonds
(electrons) the substance has--these influence what visible frequencies
that are absorbed or transmitted. Occasionally a coating or film on the
material can establish its color via light interference such as with oil
on water or the color of some insects and mollusk shells. If a material
(pigment perhaps) loses color often its structure has changed, the
breakdown of a film, change in particle size, or when some of its
chemical bonds are broken and perhaps different bonds formed. In all
cases the light frequencies coming from the object are now different.
Often UV light over time can either fade (photograph or vinyl siding) or
intensify a color (hardwood flooring) because its changing the material
-its changing the chemical bonds near the surface. There is much more
to learn and say about this. As you get older and you study more
chemistry and physics these concepts will make more sense.
Lou Harnisch
Ariana,
I am thinking that the color you mean are the color that we find in
clothing, paint, crayons and things like that. The color in these
things come from an added chemical known as a dye. Dyes are chemical
compounds that are added to the objects that we see and give it
their color. So when these compounds are somehow removed, like when
they are rubbed off or washed off, what is really happening is that
these compounds are being taken away. When there is less of these
compounds in the object then it looks faded.
Greg (Roberto Gregorius)
Sunlight looks white, but is made up of all the colors. We see this
when water drops in the air break sunlight into all the colors of a
rainbow.
When light shines on something colored, like sunlight on a red jacket,
all colors except red are absorbed by the dye. The red colored light
bounces off and reaches our eyes. We see red.
We know that light, except for the red, is absorbed because the jacket
gets warm. That is from other colors of light that the red jacket
absorbs. (That is also why we wear white in the sun. It reflects all
the colors in sunlight and keeps us cooler.)
As dyes get older, they lose their strength and they cannot absorb other
colors of light. All the colors bounce off and reach our eyes. The
color looks whiter. We say the jacket has faded.
What is interesting is that strong sunlight fades almost any color. The
sunlight is destroying the dye as it is absorbed!
Bob Avakian
Oklahoma State University - Okmulgee
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