Classification of painted steel sheets (2)
The composition and function of the paint.
Various coatings have four parts, namely (1) resin (2) pigment (3) solvent (4) auxiliary agent.The solvent is volatile, and its three parts are basically non-volatile.
The resin is the film material, is the main composition and foundation of coating, also known as base material, it is the main factor that decides the film character.
The resin that is required to be a film material is stable during the coating storage period without obvious physical changes and chemical changes.When the film is formed, it can be rapidly solidified into a film under specified conditions.
There are various kinds of resins. The resin used in coil coating is acrylic resin, epoxy resin, polyester resin and polyurethane resin.Different tree ` fat, its physical properties and chemical properties, and weather resistance, corrosion resistance and so on are not the same.
Pigment must be used in combination with the resin. The main function of paint is to make the film colouring, and the proportion of pigment can affect film hardness, glossiness and corrosion resistance.
Solvents are an important part of liquid coatings, which are volatile components in the coating drying process.The solvent is also used to adjust the viscosity of the paint, which is used to adjust the viscosity of paint.Solvents have great influence on the manufacture, storage, coating, film formation and film quality of coatings.
Additive is a small additive to improve coating performance.The amount of additives used in coatings is very small, but the effect is significant. For example, some can improve the performance of coating and coating, some can improve drying time, and some can prevent the film from producing pathological conditions.There are many kinds of additives, such as drying agent, curing agent, leveling agent, antifoaming agent, anti-light agent, stabilizer and so on.
Almost most liquid coatings are made up of some of the four ingredients listed above, the most important of which is the resin, which is indispensable for any coating.It can be said that resins (sometimes with solvents and additives) are transparent paint, and then add paint to make all kinds of paint.
Color coated steel plate is generally divided into two categories according to the purpose: construction and home appliances.Architectural coatings are selected in epoxy resin, polyester resin, polyvinyl chloride plastics, silicone modified polyester and polyvinylidene fluoride, depending on the environment.Home appliance paint general color polyester resin.