Patent ID: 6713163
Filing Date: 2004-03-30
Classification: H05K,Y10S,Y10T

Abstract:
A multilayered printed wiring board, comprising:a plurality of insulator layers, each formed of a glass cloth impregnated with an epoxy resin composition; a plurality of metal foil layers, in each of which a circuit is formed, the metal layers being laminated alternately with the insulator layers, each of the insulator layers being placed between two of the metal layers; and a cavity providing continuity between the metal foil layers alternately laminated with the insulator layers, wherein the epoxy resin composition comprises at least phosphate ester, aluminum hydroxide, silica, calcium oxide, strontium titanate, and iron oxide, and wherein inorganic components are provided in the insulator layers as about 8% to about 18% by mass of phosphorus pentoxide (P2O5), about 20% to about 28% by mass of aluminum oxide (Al2O3), about 0.1% to about 0.6% by mass of silica (SiO2), about 0.1% to about 1.0% by mass of chlorine (Cl), about 15% to about 20% by mass of calcium oxide (CaO), about 0.3% to about 0.5% by mass of titanium oxide (TiO2), about 0.2% to about 0.4% by mass of iron oxide (Fe2O3), and about 0.1% to about 0.3% by mass of strontium oxide (SrO), in converted values as measured by an X-ray fluorescence analysis.