After the water-based coating wets the substrate, the additive to control its flow and leveling is the leveling agent. Water-based leveling agents are commonly used in water-based systems. How can we know the quality of water-based leveling agents and choose products with excellent performance?
Most of the existing water-based coatings are water-dispersed rather than water-soluble. They are different from solvent-based coatings in their dependence on various coating additives. Very big. In the formulation design, production process and coating process of water-based coatings, additives are needed to achieve the good functions of the coating.
Water-based leveling agent is an indispensable type. Its function is to help water-based paint form a smooth, flat and even coating on the surface of various substrates. film, so the quality of leveling agent is very important. Only by mastering the method of judging the quality of leveling agents can we choose excellent products when purchasing.
Generally speaking, we can use the following four methods to roughly judge the quality of paint leveling agents.
(1) Visual inspection
After the paint is applied and dried according to the specified painting method, if you see no shrinkage holes or pinholes on the surface of the paint. Defects such as orange peel, silk marks, brush marks, and haze can be used to determine that the leveling properties of this paint leveling agent are good.
(2) GB/T l750-1979 Determination of paint leveling properties
This method is to measure the time required to achieve leveling by brushing/spraying paint on a certain substrate according to a certain method.
(3) GB-Sl07 horizontal fluidity determination method
This method is to measure the diameter of the epoxy powder coating test piece after melting at a certain temperature.
(4) ASTM D2801 Leveling Test Method
The leveling grade is determined by the ability of pairs of two strips of paint to flow together using a New York Paint Council (NYPC) leveling blade.
To sum up, there are four methods for testing water-based leveling agents. The first one has no quantitative indicators and can easily cause disagreements.
The latter three are special standards developed by people in the domestic and international coatings industry to evaluate the leveling properties of coatings leveling agents.