Top binding is defined as a second application of a bonding agent during the manufacture of coated abrasives. It is laid over the base bond material attaching the grains to the backing material. The main purpose of the top binding - also referred to as size coat - is to anchor the abrasive grain firmly to the bond.
It is primarily intended to provide additional support against lateral forces to which the grain is subjected constantly during the grinding process. One of its secondary effects is that it gives the product its typical colour.
Type and quantity of the top binding agent have a significant impact on the grinding performance of an abrasive. Klingspor always uses a resin to produce the top binding on their abrasives as this bonding agent offers significantly higher strength and adhesion than glue binders or other natural binding agents and, thus, delivers noticeably enhanced grain adhesion and higher grinding performance. The quantity of the top binding agent is laid down for each type in the recipe and adapted to and optimised for the corresponding application. Klingspor constantly monitors the application of the top binding during the production of coated abrasives using laser measurements and by performing spot weight measurements on defined sample to accurately verify the compliance with the specifications given in the recipe.
The top binding plays a pivotal role in all coated abrasives, especially in abrasive belts due to the high cutting speeds and the great amount of stress to which they are subjected. Adding certain ingredients to the top binding makes it possible to enhance the properties of abrasive belts even further and to make them ideally suited for the applications for which they are used, e.g. addition of grinding active fillers to LS 312 JF, CS 411 Y and similar tools for stainless steel processing
Back to Grinding terms and definitions