1, solvent-based coating
1 in transparent varnish, the addition of matting agent can not be produced in the storage of hard deposition, but also can not affect the transparency of the final film. Therefore, as mentioned above, the organic treatment of matting agent is the best choice. The extinction agent treated with organic matter can also bring some other benefits, such as smooth surface, abrasion resistance and so on.
2 in the paint system, due to the addition of pigments, the proportion of pigments is much larger than the extinction agent, so the precipitation of matting agent is not a problem. For cost-saving consideration, you can choose the matting agent without surface treatment, but sometimes, in order to improve the feel and abrasion resistance of the paint film, the organic treatment matting agent can be selected.
In the solvent-type system, the particle size of matting agent should be based on the coating system of dry film thickness and the required surface properties of the paint film, a relatively fine matting agent will make the surface of the paint film relatively smooth, feel better, but its extinction efficiency is less than the coarse matting agent. and closed-hole wood paint, feel the demand is higher, so to choose a thinner matting agent.
2, water-based coating system
With the increasingly prominent environmental issues, the traditional solvent-based coatings are gradually replaced by some environmental-friendly coatings, water-based coatings, especially for the development of waterborne coatings for wood, the demand for silica matting agent is more and more. Although the traditional matting agent can be used to eliminate the light of waterborne coatings, there are many drawbacks. The water-based coating system has a low viscosity, so the extinction agent is required to affect the system as small as possible, that is, the amount of oil absorbed by silica is as small as possible, and it must be beneficial to disperse in the aqueous system.
3. UV Curing Coating System
Compared with water-based coatings, UV curing coating is very difficult to eliminate light. Extinction ability depends on the nature of the formula, resin reactivity and curing conditions. Usually, low reactivity and slow curing conditions are beneficial to extinction, and the high reaction curing system is difficult to eliminate light. Most of the UV-curable coating system should not affect the viscosity of the system, so the oil absorption of silica should be as small as possible. The manufacturing process of this matting agent is different from the traditional silica matting agent. At the same time, the small amount of oil-absorbing agent is often a large proportion of the heap, easy to precipitate, the special treatment must be used.
4. High solid separation coating system
The high solid content of the coating is high, and the amount of matting agent in the formula should be increased. Ordinary matting agents tend to cause a significant increase in viscosity. Therefore, we should choose the most coarse matting agent with high porosity and acceptable particle size. The average particle diameter is usually coarse to 11µ and the high porosity extinction agent of M is chosen. In addition, in order to get a better extinction effect, the particle size and coating thickness of the dry film matting agent is usually used.