1. Good suspension performance, in casting coatings, the main function of bentonite is suspension, which can make the characteristics of the casting coating itself uniform. In this way, the surface finish of the casting workpiece can be guaranteed.
2. Strong high temperature resistance, in the casting process, the temperature of the part in contact with the metal liquid generally reaches 1200 degrees Celsius, and the casting coating in this environment must be able to withstand the test of high temperature.
3. Good fineness, generally used to make casting coatings bentonite, its fineness requirements are at least 325 mesh or more. Some high-end products require thousands of eyes.
4. High purity, generally used to make casting coatings bentonite requires high purity, not allowed to have too many impurities. This is conducive to affecting the quality of the cast workpiece due to excessive impurities in the casting process.
In short, bentonite for foundry coating bentonite is much higher than that of general products. In real production, there are high-end sodium-based bentonite with high purity and expensive lithium-based bentonite. Regardless of the product, the amount of bentonite consumed by this industry is still very small.
parameter | Blue absorption g/100g | Gumseed price ml/15g | Expansion times ml/g | PH value | Moisture % | Fineness (-200 mesh) |
Sodium-based | >35 | >110 | >37 | 8.0-9.5 | <10 | >180 |
Calcium-based | >30 | >60 | >10 | 6.5-7.5 | <10 | >180 |
1. Improve the suspension and thixotropy of the coating, and increase the storage time of the coating;
2. Improve the hiding power, brushability and flatness of the coating;
3. Improve the refractory degree and water resistance of the coating and the adhesion and adhesion of the coating coating;
4. Bentonite can replace heavy calcium powder and reduce the cost of coating production;
5. Improve the low temperature resistance of the coating.
Bentonite can act as a dispersant and thickener in coatings. In addition, it also plays a certain role in the adhesion of the coating, waterproof ability, high and low temperature resistance, smoothness, etc. At present, the use of bentonite in paint production is gradually deepening. With the development of science and technology, coating bentonite will be more widely used.
The selection of coating bentonite is to pay attention to several parameters are whiteness, fineness, expansion times. Bentonite for coatings that meet these parameters can meet the basic requirements of coatings during use. It is recommended that you use the soil ace paint bentonite, which has excellent quality and reasonable price