New fiber glass reinforced laminates for high quality electronic substrates

Self-extinguishing fiber glass mat reinforeed polyester resin laminates have been developed of greater than seven times the impact strength of the conventional paper reinforced phenolic and epoxy laminates. Punching of 1 over 16? laminates with suitable tools will produce 1 over 16? holes on 200 thousandths centers with no ?haloing,? radial cracks from the holes, cracks between the holes, or fibers in the holes. The D24/23 electrical loss at one megacycle appears controllable to equal to or one-half of the electrical loss of paper reinforced products. The insulation resistance is comparable after 96 hours at 35?C and 90% RH. Water absorption can be controlled to approximately one-half that of the paper reinforeed products. Surface resistance can be controlled to a higher value than for the NEMA grades of XXXPC and FR-3 measured in parallel.