Definition expansion of plastic materials includes conversion into moulding powders under excise law, widening regulatory coverage. The Finance Act, 1984 inserts a new sub clause (ix) into clause (f) of section 2 of the Central Excises and Salt Act, 1944, providing that, in relation to artificial or synthetic resins and plastic materials, the term includes their conversion into moulding powders, thereby bringing such conversion and resulting materials within the Act's excise scope.