Resin composition, B stage sheet, metal foil with resin, metal substrate, and LED substrate

The invention provides a resin composition, a B stage sheet, a metal foil with resin, a metal substrate, and an LED substrate. The resin composition includes 2-functional epoxy resin with a biphenyl structure, a phenolic resin, a first aluminium oxide group with a grain diameter D50 from 7mum to 25mum, from a small grain diameter side, corresponding to 50% accumulation, a second aluminium oxide group with the grain diameter D50 from 1mum to 7mum and a third aluminium oxide group with the grain diameter D50 smaller than 1mum. A ratio of the phenolic resin to the epoxy resin is from 1.00 to 1.25 in terms of a equivalent standard.