Patent ID: 8071882
Filing Date: 2011-12-06
Classification: F21K,F21Y,H01L,H05K

Abstract:
1. A metal base circuit board having an insulating layer and a conductive circuit or metal foil alternately laminated, characterized in that the thickness of the conductive circuit or metal foil is from 5 μm to 450 μm, the insulating layer is made of a cured product of a resin composition comprising an inorganic filler and a thermosetting resin, and the thickness of the insulating layer is from 9 μm to 300 μm, wherein the insulating layer is a cured product of a resin composition comprising from 25 to 60 vol % of the thermosetting resin and the rest being the inorganic filler having a sodium ion concentration of at most 500 ppm and comprising spherical coarse particles having the maximum particle size of at most 75 um and an average particle size of from 5 to 40 μm and spherical fine particles having an average particle size of from 0.3 to 3.0 μm.