Paints are used for aesthetic purposes as well as to prevent the surface from weathering. Paint effectively reduces the chemical attack and other erosion effects. Paints are also helpful in the prevention of moisture penetration in the concrete.
Here are some types of paint
This type of paint is highly useful in painting gas tanks, hot water pipes, marine pieres, Oil storage tanks etc. In this type of paint finely ground aluminium is suspendes in either quick drying or fast drying varnish as per requirement.
Advantages of aluminium paints are as follows.
- This could be visible even in the darkness.
- It has a high covering capacity. It could cover 200 square meter per litre of paint.
- Best suitable for iron and steel steel surfaces as it could prevent the corrosion.
- It gives the best appearances to the surface.
Anticorrosive paint is essentially a mixture of oil and a strong dryer. This is suitable for the inner surfaces of water tanks.
The advantages of this type of paint is as follows.
- It is cheap
- It lasts for a longer duration
- The appearance of the paint is black.
The asbestos paint finds its application in paintinf surfaces exposed to acidic gases and steam.
By mixing asphalt with oil or petroleum we can get bitumenous paint. It is use on iron surfaces which are going be underwater exposure.
The cellulose paint is prepared from nitro-cotton or celluloid sheets. It gets dried by evaporation of thinner. Cellulose paint does not affected by water and used on the surfaces which are exposed to hot or cold surroundings.
To apply cement paste the skill required is the least. Also, it is not necessary to remove formerly applied paint from the surface. One more advantage is that it could apply even on wet surfaces which is not possible with oil paint or other paints.
Cement paint is manufactured with white cement, pigments, accelerators, and other additives. Also, cement paint is the most economic from the point of view of cost.
Colloidal paint is specially used for interiors. It takes more time to settle and no inert material is used in the preparation of the same. It also penetrates through the surfaces.
Numerous type of emulsion paint is available in the market today. They are made from polyvinyl acetate and synthetic resins along with color pigments. They are settled within half an hour to one hour. Also, they retain their color for a longer duration.
Emulsion paints are applied with a brush and generally applied in two coats.
It contains white lead or zinc white, oil, petroleum spirit, and other additives for color.
Enamel paints come in a variety of colors. For better opacity, it is advisable to use the first coat of titanium dioxide with pale linseed oil. This type of color is resistant to acid and alkali attacks.
It is most useful on surfaces exposed to ammonium, chloride, and sulphate gases. It presents a black appearance.
No turpentine is used in the making of inodorous paint but white lead or zinc white is used with methylated spirit. This type of paint is not durable.
This type of paint shines like radium after the source of light is cut off. This is made up of calcium sulphide with varnish.
Oil paints are generally applied in three coats with varying compositions namely the first coat as a primer, the second coat as undercoats, and the final one as final coats. This is the most commonly used type of paint.
Plastic paint comes in many varieties under different brand names. Plastic paint gives a pleasing appearance and it is used for houses, auditoriums, etc. Generally, two coats of plastic paint are used for practice. Plastic paints are cheaper than emulsion paint.
Silicate paint has no chemical interaction with the surfaces on which they are applied. Two or three coats of silicate paint are recommended.
Synthetic rubber paint
The paint is prepared from resins and offers good resistance to water. It dries quickly and gives uniform color. This can even be applied on surfaces that are not completely dry say wet concrete.
Followin is a list of paint manufacturing companies that offer vast types of paint.
Characteristics of the ideal paint
- It should possess a good spreading power means maximum area of the surface should be cover with the minimum quantity of paint.
- The paint should be economic and not costlier.
- The paint must retain its color for longer time.
- The paint should have good workability.
- The paint must dry in reasonable time.
- The paint should make hard and workable surface.
- The paint should not be affected by weathering or atleast it should be weather resistent.
- The paint when dries should not make cracks on the surface
- The Paint must not be hazardous to ensure safeguard of the workers.
- The paint must be eco friendly. It must have least impact on environment.
- The paint must give pleasing and attractive appearance.
Common defects in the painting
- Blistering : This happens because of vapour of water on trapped in the paint.
- Bloom : Formation of dull patches on the painted surface is called blooming.
- Fading : The gradual fading is because of sun light. The paint slowly loses its opacity.
- Flaking : The formation of small loose patches is called flaking and it is because of poor adhesion.
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