For Gasket Phenolic Black 1/4 Bakelite Sheet is a generic named material based on the thermosetting phenol formaldehyde resin.1/4 Inch Black Bakelite Sheet was the first plastic made from synthetic polymers.Insulation Black Bakelite Sheet was used for its nonconductive and heat-resistant properties in radio and telephone casings and electrical insulators. The retro appeal of old Black Bakelite Sheet products, especially kitchenware and toys, has made them quite collectible in recent years. Black Bakelite Sheet is a hard, dense material made by applying heat and pressure to layers of paper or glass cloth impregnated with synthetic resin. These layers of laminations are usually of cellulose paper, cotton fabrics, synthetic yarn fabrics, glass fabrics or unwoven fabrics. When heat and pressure are applied to the layers, a chemical reaction (polymerization) transforms the layers into a high-pressure thermosetting industrial laminated plastic.