Abstract: Epoxy laminates incorporate up to 20 wt. % talc particles, particularly pure Montana platy talc particles having a maximum particle size of about 40 &mgr;m providing improved drilling performance, reduced dust formation, and improved Z-direction CTE, particularly when the epoxy resin has a Tg of about 150° C. or higher. The talc is selected from those which do not significantly reduce the electrical strength of the laminate relative to those which contain no talc particles. Characteristically, the talcs will have less than 5 wt. % impurities and less than 0.01 wt. % (100 wt.ppm) water extractable anions.