2021-11-17 Pageview:753
The appearance of this nano titanium oxide photocatalyst is white loose powder. It has strong redox ability under the action of visible light or ultraviolet light, and can decompose harmful organic matter, pollutants, odor, bacteria, microorganisms and other harmful organic matter into harmless CO2 and H2O, and has the characteristics of pollutant removal, hydrophilicity, self-cleaning, etc., with long-lasting performance and no secondary pollution.
The porosity of the paint film is artificially introduced before reaching the critical pigment volume concentration
The technique of attracting human holes in the paint film has existed as early as the early 1920s. In 1978, Seiner El conducted an extensive review of related literature, citing a 1921 patent on whitening paint film. In this example, the pores are introduced into the paint film during the drying process of the nitrocellulose acetone solution in a high-humidity environment. With the appearance of acetone, the surface temperature of the paint film drops, causing the moisture in the environment to condense on the surface of the paint film and mix with the internal ketone solution. After the acetone is completely volatilized, the volatilization of the remaining water droplets leads to the generation of pores in the paint film. Seiner’s article also cited other examples for the reference of interested readers.
Closed stomata
Rohm and Haas researchers make full use of the characteristics of pore covering and take the lead in developing commercial covering polymer products. Its unique feature is that the pores are closed, car wax with ptfe so it will not negatively affect the resistance of the paint film after drying. The materials and techniques used in the first two cases will leave open holes in the dried paint film and reduce the resistance of the paint film. Glass or ceramic microspheres on the market have a similar closed pore structure, but their diameter is generally tens of microns, which limits their use in coatings. At the same time, their pore size is large, which can’t effectively scatter light and decrease due to the aggregation of pigments. The scattering efficiency of titanium dioxide, the biggest use of this type of material is to act as a low-density filler for caulking glue and filling glue.
Covering theory
The hiding power of Iraqi paint can be understood as its ability to cover the contrasting colors of the background. The effect of covering and covering polymer 681 is mainly due to light scattering caused by titanium dioxide or light absorption due to the presence of colored substances. When the intensity of the incident light decreases due to these two reasons, the covering phenomenon occurs. In practice, we can use the absorption of light to improve the covering of the paint. Adding a very low amount of black pigments (carbon black or some other dark pigments) to the white paint can greatly improve the covering ability of the white paint.
Leave a message
We’ll get back to you soon