Cellulose ether products are derived from natural cotton pulp or wood pulp and are produced through etherification reaction. Different cellulose ether products use different etherifying agents. Hydroxyethyl cellulose (HEC) uses ethylene oxide as the etherifying agent, and hydroxypropyl methylcellulose (HPMC) uses other types of etherifying agents. (Methyl chloride and propylene oxide).

In spray cork and latex paints, hydroxyethyl cellulose (HEC) can be used as a thickener.

spray cork uses a large amount of aggregates, has a large specific gravity, and is easy to precipitate. It is necessary to add a thickener to increase its viscosity to meet the viscosity required during construction and spraying, improve its storage stability, and achieve a certain strength.

If you expect spray cork to achieve good strength, good water resistance and weather resistance, the selection of raw materials and the design of the formula are very important.

Under normal circumstances, the amount of emulsion used in high-quality real stone paint will be relatively high.

For example, in one ton of spray cork, there may be 300kg of pure acrylic emulsion and 650kg of natural colored stone sand. When the solid content of the emulsion is 50%, the volume of 300kg of emulsion after drying is about 150 liters, and the volume of 650kg of sand is about 228 liters. That is to say, the PVC (pigment volume concentration) of the spray cork at this time is 60%. Because the particles of colored sand are large and irregular in shape, under certain particle size distribution conditions, the dried spray cork may be at the CPVC (critical Pigment volume concentration) around. As far as the thickener is concerned, if cellulose ethers with appropriate viscosity is selected, spray cork can form a relatively complete and dense paint film to meet the three major performance requirements of spray cork. If the content of the spray cork is low, it is recommended to use cellulose ethers with a higher viscosity as a thickener (such as 100,000 viscosity), especially after the price of cellulose ether increases. This can reduce the use of cellulose ethers and make the spray cork. The performance of the paint is even better.

Some economical spray cork manufacturers use hydroxypropyl methylcellulose instead of hydroxyethyl cellulose due to cost and other factors.

Comparing the two cellulose ethers, hydroxyethyl cellulose has better water retention, will not lose water retention due to gelation at high temperatures, and has a certain degree of mildew resistance. For performance reasons, it is recommended to use hydroxyethyl cellulose with a viscosity of 100,000 as a thickener for spray cork.