كل ما تحتاجه هوايتك

The active agent in Darvan is polyacrylic acid. Its molecules are negatively charged along its entire length. They stick to clay particles and cause them to repel each other. Darvan No. 7 is a high molecular weight long chain polymer that has been successfully used as a general purpose dispersing agent for both ceramic and glass bodies. It is a liquid alternative to the popular sodium silicate. About twice the amount normally required (0.4-0.5%) but Darvan offers a number of advantages. Usually, soda ash is not needed as a supplement and Darvan does not attack the gypsum molds. In addition, the slurry is less sensitive to overdischarge and more stable. Source: Digital Fire.