Commonly used types of paint
People have used paint for centuries as a means of adding color to the
world. Paint also protects and covers houses and cars and provides markers
for traffic on the streets or signs for businesses. Paint can add beauty
and cover the faults of an otherwise drab artificial environment. Paint
itself is a mixture of liquid and powder; the powder is the pigment that
gives color to the paint and the liquid is what binds it and allows it
to spread. In some paints a solvent, or thinner, is used to make the paint
easier to spread. The kind of liquid and solvent used is determined by
the kind of paint being made. There are many kinds of paint and they have
many different uses.
Oil-based paints are thick and are commonly used as a protective barrier.
Outside paints can protect houses and buildings from weather and the elements,
while wall and floor paints provide color to the inside. Wall paints can
be glossy, semiglossy, or flat, depending on the amount of inert pigment
in the paint. The larger the amount of pigment, the flatter the paint,
and the smaller the glossier. Metal protective paints are used on the
metal machinery of farms and factories and on the surfaces of structures
such as bridges or boats. These paints prevent the formation of rust and
damage caused by corrosion from wind, water, and other variables.
Latex paints can be used indoors and outdoors much like oil-based paints,
and are generally preferred due to their ease of use. Because these paints
are water-based, they can be cleaned up with soap and water, however,
latex wall paints are not as glossy as oil-based. Latex masonry paints
are used mainly on bricks and cement and form a film that holds in the
alkali on the surface.
Primers are used as the first coat on plaster and wood walls and usually
have a varnish or synthetic resin base. They coat and flow into the uneven
surface, filling in the tiny holes and cracks to allow the next layers
of paint to be smoothed across without soaking into the wall. Enamels
are used to cover inside and outside surfaces. They contain little pigment
and provide a glossy sheen most commonly seen in kitchens and washrooms.
Lacquers are used to paint automobiles and are made with synthetic resins
and fast evaperating solvents. Pigment is added to the solution and, after
application, the paint dries quickly as the solvent evaperates. Metallic
paints use alluminum or bronze powder that gives a metallic sheen when
the flakes float to the surface of the paint film.
Fire-retardent and heat-resistant paints are used where there is danger
of high heat or fire. Fire-retardent paints use an oil or oil resin base
and have chemicals that cause it to blister and form an insulating barrier
between the fire and the wall. The paint will burn but can be put out
once the igniting fire is removed. Heat-resisting paints cover warm or
hot surfaces such as ovens, boilers, or the cylender heads in aircraft
engines. Alkyd-resin bases are used in paints for moderately hot surfaces
while silicone-resin is used for higher temperatures. Very hot surfaces
use a metallic pigment mixed with varnish to evaperate and leave only
the pigment bonded to the surface.
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