In a powder sintering method the articles are decorated by a thermoplastic film. The film may be stuck to the wall of the p mould by an adhesive or may be formed from coloured powder which is also stuck to the wall by an adhesive. The mould walls may be painted with a decoration. Another method is to produce an uncoloured plastic film adjacent to the walls either by using a preform or by beating thermoplastic powder, and strewing coloured powder on the film whilst it is still stickly to form the decoration. The adhesive may be silicon oils and fats, or a pasty mixture of solid and liquid hydrocarbons. The Specification describes several examples.
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