Photo Sensitive Solder Resist containing High γ-relaxation Unit to High Resistance at Thermal Shock Test and Insulation Reliability

Abstract

With the sophistication and miniaturization of electronic devices, printed wiring boards are progressing to ever-higher densities. In the field of solder resist (SR), the miniaturization of the wiring with higher density has led to an increasing demand to improve reliability (thermal shock resistance and insulation reliability). We have shown that it is effective to increase γ-relaxation, which is an index of the stress relaxation at low temperatures, in order to improve both the thermal shock resistance and insulation reliability of the solder resist.