What's the difference between different types of coatings according to function?

Today we will say: according to the function of paint into several categories? What is the difference between primer and finish? "

Classification of coatings by function

In terms of function, coatings are generally divided into four types(from bottom to top): closure, primer, medium coating, and finish paint.

Closure: Used for wood substrates, closed isolation.

Primer: Filling and increasing thickness and other functions such as rust prevention. If it's latex, it's also anti-alkali and anti-mildew.

Medium coating: increased thickness, more common in the ground paint, some have other special functions, such as anti-static. (Also used to prevent varnish exposure)

Paint: Decoration and aesthetic, surface decoration and protection against wear.

Differences between primer and finish

Latex paint is divided into primer and finish paint, primer has the effect of alkali resistance and plasticization. But it doesn't have to be primed, mostly from an economic point of view. Primer is generally used in conjunction with mid-to-high grade finish paint, and if the use of low-grade finish paint is not necessary to brush primer, primer prices are more expensive than finish paint, then there is still need to brush primer? Even if the brush, because of the poor paint, it does not reflect the advantages of brush primer.

What is the difference between paint and primer?

1, different composition

The primer consists of four parts: resin, filler, solvent and auxiliary agent; The difference between the surface paint component and the primer is mainly due to the small or no filling of the former.

2, play different roles

The primer is the first layer of the paint system. It is used to fill the paint surface, support the paint, provide fullness, reduce costs, and help save energy. The paint is the final coating of the paint, and it is the last coating layer in the construction wall decoration. To increase the number of paint layers and thick paint to increase the thickness of the paint film. The thickness of the coating is mainly provided by the primer, and the paint is mainly used for decoration and protection.