How many kinds of bonds used in the producing coated abrasive?

Coated abrasives use one of two types of adhesives. One is based on animal glue and the other is based on synthetic, heat-hardenable resins. The adhesive is applied with a minimum of two bonding applications. The first or “maker” coat adheres the abrasive grain to the backing, ensuring proper anchoring and orientation. After drying or curing, the second or “sizer” coat is applied. The sizer adhesive unites with the maker bond to provide final grain anchoring and proper total-adhesive level for the finished product.

Glue Bond Glue has a tendency to soften from the normal heat of grinding. Glue bond products usually produce a more uniform, less harsh finish which, in the case of fine grits, can be easily buffed out. Resin Bond Resins offer greater heat resistance and are more durable in heavy stock removal operations. Resin bond products are the best all-around coated abrasives. However, they have a tendency to produce a harsher, more scratchy finish which, in the case of finer grits, is more difficult to buff out.