GB772850A - Imitation mother of pearl and the manufacture thereof - Google Patents

Abstract

Artificial mother of pearl is obtained by polymerizing an unsaturated polyester in the presence of 1.5 per cent of pearlescent material, the mixture being agitated, e.g. at 30 DEG C., in a good heat conducting container, e.g. of aluminium, until just before gelling occurs, e.g. at 35 DEG C., and the mixture then poured into a mould, e.g. of "Cellophane" (Registered Trade Mark), and slow agitation continued until polymerization is complete. The slow agitation may be effected by progressively compressing the mould, or by the presence in the mixture of a volatile organic solvent, such as acetone, methyl-ethyl or methyl-isobutyl ketone, dibutyl phthalate or chlorinated or cyclic solvents. The pearlescent material may be fish scales or aluminium shavings suspended in an organic liquid such as dibutyl phthalate. Polymerization catalysts such as benzoyl or methyl-ethyl ketone peroxide may be included. The pearlescent effect of plates of the products may be improved by painting the lower surfaces with white paint, or by welding to opaque plastic, e.g. to polyester resin containing talcum powder or titanium dioxide. The artificial mother-of-pearl obtained may be used as knife-handles or buttons.ALSO:Artificial mother-of-pearl is obtained by polymerizing an unsaturated polyester in the presence of 1,5 per cent of pearlescent material, the mixture being agitated, e.g. at 30 DEG C., in a good heat conducting container (aluminium for instance) until just before gelling occurs, e.g. at 35 DEG C., and the mixture then being poured into a mould, such as a Cellophane (Registered Trade Mark) mould, and slow agitation continued until polymerization is complete. The slow agitation may be effected by progressively compressing the mould, or by the presence in the mixture of a volatile organic solvent. The pearlescent material may be fish scales or aluminium shavings suspended in an organic liquid such as dibutyl phthalate. Polymerization catalysts such as benzoyl or methyl-ethyl ketone peroxide may be included. The mother-of-pearl obtained may be used as knife-handles or buttons.