Consequently, it does not matter that the source used to be coal tar and is now the petrochemical industry. “It’s old-fashioned and old chemistry,” he said. “Most of these things can now ...

Other products, such as asphalt/coal tar blends, and material containing ... differently to get the properties they want so the chemical composition of the asphalts might be different." ...

Grace Calvert and Charles Lowe have prepared from coal tar products of a most extraordinary ... The processes by which these wonders of chemical art are manufactured are not yet known; but we ...