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The makeup of PaintIn general terms, all paints have four basic components which make up the paint. These components are:
PIGMENTSProvide color and hiding; some are used to impart bulk at relatively low cost. The pigment is responsible for the color of the paint. They can be found throughout nature in clays, herbs, nuts, berries, barks, carbon, charcoal, and soot. They are ground down into powder and usually boiled several times in water to remove impurities.
A pigment is a material that changes the color of light it reflects as the 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 wavelengths of light.
Materials that humans have chosen and developed for use as pigments usually have special properties that make them ideal for coloring other materials. A pigment must have a high tinting strength relative to the materials it colors. It must be stable in solid form at ambient temperatures.
BINDERThe binder is the main body of the paint, holds the paint together and carries the pigment. The choice of a binder depends on how much paint you need and the surface to be coated. Natural binders that can be used are chalk, lime, casein (non-fat milk curds), animal or vegetable glues, and oil.
Slaked chalk, also called whiting, makes a paint called distemper used for interior walls and ceilings. Lime has antibacterial qualities and is used for interior or exterior walls.
Casein is the binder for milk paints; it is used for interior walls and for fine arts. Animal glues and vegetable glues make chalky paint and are usually used in fine arts. Oil is used for woodwork paint and fine art. It "binds" the pigment together, and provides film integrity and adhesion.
CARRIER/VEHICLE/SOLVENT/LIQUIDIt provides desired consistency and makes it possible to apply the pigment and binder to the surface being painted. The main purpose of the vehicle is to adjust the viscosity of the paint. It is volatile and does not become part of the paint film.
It can also control flow and application properties. Its main function is as the carrier for the non volatile components. Water is the main vehicle for water based paints.
Solvent based, sometimes called oil based, paints can have various combinations of solvents as the vehicle, including aliphatics, aromatics, alcohols, and ketones. These include organic solvents such as petroleum distillate, alcohols, ketones, esters, glycol ethers, and the like. Sometimes volatile low-molecular weight synthetic resins also serve as diluents.
ADDITIVESThese are low-level ingredients that provide specific paint properties such as mildew resistance, defoaming and good flow and levelling. Besides the three main categories of ingredients, paint can have a wide variety of miscellaneous additives, usually added in very small amounts.
Some examples include additives to improve wet edge,
improve pigment stability,
impart antifreeze properties,
control skinning, etc.
Other additives might be thickeners, coalescent solvents, or biocides to fight bacterial growth.