What is the meaning of Pigment? Concept, Definition of Pigment

Definition, Concept, Meaning, What is Pigment


Concepto de Pigmento

1. Concept of pigment

A pigment is a material that changes the color of the light that reflects as a result of selective color absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which the material itself emits light. Many materials selectively absorb certain waves of light, depending on its wave length. Materials that humans have chosen and produced to be used as pigments usually have special properties that make them ideal for coloring other materials. A pigment must have a high tenidora strength relative to materials that colors. It should also be stable in solid form at room temperature.
The pigments are used for coloring paint, ink, plastic, textiles, cosmetics, food and other products. Most of the pigments used in manufacturing and in the Visual Arts are dyes dry, usually in the form of fine dust. This powder is added to a vehicle or parent, a relatively neutral or colorless material that acts as an adhesive. For industrial applications, as well as artistic, permanence and stability are desirable properties. Pigments that are not permanent are called fugitive. Fugitive pigments fade with time or with exposure to light, while others end up black.
Usually distinction is made between a pigment, which is insoluble in the vehicle (forming a suspension), and a dye, the which is a liquid or is soluble in the vehicle (resulting in a solution). A dye can be a pigment or dye depending on the vehicle in which it is used. In some cases, a pigment can be manufactured from a dye by precipitating a soluble dye with a metallic salt.
The pigments have been used since prehistoric times, and have been instrumental in the Visual arts throughout history. The main natural pigments used are biological or mineral origin. The need for less expensive pigments given the scarcity of some colors, like blue, led to the emergence of the synthetic pigments.
Pigments produce their colors since they selectively reflect and absorb certain light waves. White light is approximately equal to a mixture of all of the visible spectrum of light. When this light encounters a pigment, some waves are absorbed by chemical bonds and substituents of the pigment, while others are reflected. This new reflected light spectrum creates the appearance of color. For example, a dark blue pigment reflects blue light, and absorbs other colors. Pigments, unlike fluorescent or phosphorescent substances, can only steal the light waves which receives, never add new.
The appearance of pigments is intimately linked to the color of the light they receive. Sunlight has a color temperature high and a spectrum relatively uniform, and is considered a standard for white light. Artificial light, on the other hand, tends to have large variations in some parts of its spectrum. Seen under these conditions, the pigments look in different colors.
The color spaces used to represent colors numerically must specify their light source. Color Lab spaces, unless otherwise noted, assume that the measure was taken under a light source D65 (Daylight 6500 K) type, which has approximately the same color as the sunlight temperature.
Other properties of a color, such as its saturation, or luminosity, can be determined from other substances that accompany pigments. Adhesives and fillers added to pure chemical pigmentadores also have their own patterns of inflection and absorption, which can affect the final spectrum. In the same way, in mixtures of pigment and adhesive, some rays of light may not be pigmentadoras molecules, and can be reflected as is. This type of rays contribute to the saturation of the color. A pure pigment allows very little white light to escape, producing a highly saturated color. A small amount of pigment mixed with much adhesive, however, looks unsaturated and opaque, due to the large number of white light that escapes.

2 Definition of pigment

Pigment is a term with origins in the Latin language (pigmentum). It's the substance that is used for coloring paint, varnish, enamel, etc. Its action is produced by changing the color of the reflected light, since it absorbs partially the tonality and radiates a.
Thanks to the pigments, it is possible to confer a particular color to the food, clothing and cosmetics products, for example. Usually pigments are used in powder, which are added to colorless material or very faint tone. There are pigments that act as dyes permanent and others which, with the passage of time, stop dyeing the substance in question.
Although they are often used as synonyms, it is possible to establish differences between pigments and dyes. While these are liquid and allow to obtain a solution, pigments tend to be solids that create a suspension.
Note that pigments which arise by action of nature, such as iron oxide, were already used by prehistoric man. Eventually, humanity began to develop pigments through industrial mechanisms.
In the field of biology, is known as pigment to the substance which gives the key cells. These pigments that may dissolve or act as granules, define the tone of the hair, eyes and skin, among other parts of the body. Most significant biological pigments include chlorophyll (which gives plants the characteristic green color) and melanin.