Phenolic Drill Exit material to prevent exit copper burrs on the underside of the drilled circuit boards and to provide adequate space for drill stroke termination. An acceptable backup material does not contaminate the hole and helps cool the drill bit, thereby improving hole quality.
We supply Phenolic sheet as a backing material as it is a hard, dense material made by applying heat and pressure to layers of paper impregnated with synthetic resin. When heat and pressure are applied to the layers, a chemical reaction (polymerization) transforms the layers into a high-pressure thermosetting industrial laminated plastic. Ideally suited for use as a drill backing material.
Phenolic sheet material has tight thickness and flatness tolerances. It contains no abrasives that could increase drill wear or contaminates that could be evacuated through the drilled hole. The surface is smooth and hard to properly suppress exit burrs
Benefits of Phenolic sheet is that it is:
Helps cool the drill bit
Excellent dielectric strength
Good mechanical strength