Matting is to use a certain method to reduce the gloss of the coating surface . Matting methods can be divided into two methods: physical matting and chemical matting. The principle of physical matting is: adding matting agent makes the surface of the paint uneven during the film-forming process, increasing the scattering of light and reducing reflection. Chemical matting is achieved by introducing some light-absorbing structures or groups, such as polypropylene graft substances, into the paint to obtain gloss.
1. To obtain the matting effect, you can use the following methods:
1. Change the curing speed to different If the powder coating is mixed by dry mixing method, the gloss of the resulting coating film will be significantly reduced, which will have a matting effect. Since the highly reactive powder coating solidifies rapidly, the leveling and reaction of the slow-curing resin in the continuous phase is hindered, and the cured coating film eventually loses its luster. Although this method is effective, it increases manufacturing steps and costs.
2. Add thermoplastic resin. Adding cellulose acetate to epoxy powder coatings, and adding fine powdered low molecular weight polyethylene and polypropylene resin to polyester powder coatings can produce matt powder coatings. Coating film gloss is affected by manufacturing conditions. Because the addition of thermoplastic resin will affect the storage stability of the powder coating, the addition amount is limited to 2-3% of the resin amount.
3. Use special curing agent with matting effect.
4. Add fillers with matting effect.
2. Metal soap:
In order to reduce the gloss of the coating film, commonly used matting agents include ultrafine Silica, talc, aluminum stearate, calcium stearate, low molecular thermoplastic resin, etc.
Metal soap is a matting agent commonly used by people in the early days. It is mainly some metal stearates, such as aluminum stearate, zinc stearate, calcium stearate, etc. The matting raw material of metallic soap is based on its incompatibility with the coating ingredients. It is suspended in the coating as very fine particles and is distributed on the surface of the coating film when it forms a film, causing micro-roughness on the surface of the coating film and reducing the coating. The reflection of light on the film surface achieves the purpose of extinction.
微信扫一扫打赏
