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The perception of color by living beings is one of the phenomena that distinguish an animal species from the other. In this respect the eye has the property
to traduce light into electrical signals that are transferred to the brain for processing and interpretation.
 It is here where the perception of color originates, color is thus not a physical phenomena in general terms, but a psychological phenomena that allow us to appreciate
nature better, in terms of information from our surroundings. As such, it is preferable to speak of a psychochromatic phenomena when dealing with color appreciation and assessment.
Whiteness is the sensation of those colors perceived by the human eye as being white.
In physical terms there is only one type of color that is perceived as white; this is the one of those bodies
reflecting all the light impinging on them without any loss of intensity. Examples of such white are clouds and fresh fallen snow, certain pigments, remarkably Titanium dioxide, also possess this property. A
surface can be made to look white thus by coating it with a layer containing such a pigment, or by integrating it into the mass as in the case of plastic materials. Textiles and
related materials can not be made to appear white by this method, the material is bleached by chemicals means, a process that augment the amount of light reflected and thus
making it appear white. However the most extensive bleaching can not eliminate absorption of the light entirely, a small amount of absorption, remarkable of blue colored
light remains inducing a yellowness, or at best an off-white perception. The elimination of this yellowness is effectively achieved through color mixing, by using additive (through the
application of a Fluorescent Whitening Agent) or subtractive (adding a shading agent, also known as "bluing") techniques.
The color white is very important for many daily applications as a matter of esthetic but also in utilitarian sense; the use of color mixing techniques as a means to increase the
perceived whiteness is quite widespread in the industrial areas of paper, textiles, detergents and plastic.
In the paper area the color white occupies a special position as background for writing and
printing. Its higher lightness improves enormously the contrast of the print and is decisive in obtaining high quality reproductions.
Textiles are closely related with fashion, where colors play an important role as a vehicle of expression and individualism. White is also here a preferred color due to its high lightness
and neutral saturation that stimulate a sensation of newness and freshness. Maintaining these levels of whiteness is also the task of detergents, which have a dual task to fulfill:
maintain newness of fabrics (in terms of whiteness) and also show a white aspect (as a visual exposure of their force).
Plastics is comparatively a much smaller area but the tasks imposed to the additive
components is by far more demanding.
The color white is always preferred in all those applications where tidiness, freshness and
neutrality are desired properties; we must not forget that colors do not only fulfill esthetic demands but also highly utilitarian tasks, and this cannot be more true for the color white. |
