Addition of mold inhibitor BJ-85

BJ-85 anti-mildew agent for diatomaceous mud has good stability and pH adaptability. Used for cellulose, gum powder, putty powder, diatomaceous mud and other dry mix system plus antibacterial anti-mildew preservative

Additive amount 0.3-0.5%.

Addition and dispersion of matting agent
Synthetic silica matting agent has high water absorption, especially if it is not treated with wax, it will absorb moisture and agglomerate when placed under high humidity for a long time, so it should be stored in a dry and ventilated warehouse. In addition, the stacking should not be too high. Excessive squeezing will affect the dispersion.
High-speed disperser is an ideal equipment for dispersing synthetic silica matting agent.

The diameter of the stirring plate, the diameter of the container and the height of the paint should meet the requirements of Figure 12-19. Start with a lower speed to immerse the powdery matting agent into the coating system, and then increase the stirring speed to make the outer edge of the stirring blade reach a linear speed of more than 5m/s. Generally, the dispersion can be completed in 20-30 minutes. The ideal dispersion state is to keep the coating in the container in a laminar vortex state, and the center of the stirring disc can be seen. As the dispersion progresses, the temperature will increase. For the wax-treated matting agent, it is recommended that the temperature should not exceed 50°C. After dispersion, it can be checked with a scraper fineness meter (Hegman fineness meter).

The addition of matting agent will increase the viscosity of the coating, which helps to increase the dispersion shear force, which is beneficial to dispersion. On the contrary, if the viscosity is too low, the coating is in a turbulent state, which is not conducive to dispersion.

There are two ways to add synthetic silica matting agent: directly adding and adding after making matting paste.