GB566837A - Improvements relating to the manufacture of moulded articles from moulding powders - Google Patents

Abstract

566,837. Moulding buttons. HORNFLOWA, Ltd., and WINTER; H. A. M. July 7, 1943, No. 11047. [Class 43] [Also in Group V] Process: (a) (Fig. 1). Light brown, transparent powder F<1> is shaken from a sieve E', through a stencil D<1>, and forms heaps L on the relief-patterned mould base C. (b) Darker powder is shaken through another sieve and another stencil to form other heaps on the mould base (as at M, Fig. 5). (c) Body powder G, Fig. 5, of a different colour is shaken in through a sieve to complete the filling of the mould. (d) A plunger M, Fig. 5, having projections R corresponding to the heaps L, M, descends to form cavities in the body powder, and rises (Fig. 5 position). The cavities need not be of the same height as the heaps L, M. (e) More darker powder is shaken, through the sieve and stencil used in step (b), into the cavities corresponding to the heaps M. (f) More light-brown transparent powder is shaken, through the sieve E<1> and stencil D<1>, into the cavities corresponding to the heaps L. (g) The powders are compressed into tablet form by a plunger, which may be heated. (h) The tablet is reversed and placed in another mould A<2>, Fig. 11, the graining recesses formed by the plate C are filled with differently-coloured powder F<2>, a top B<2> is applied to the mould and a plunger K<2> rises, the tablet being thus moulded under heat and pressure into its final button form ; or it may be pressed a third time, in a finishing mould. The holes or other means of attachment to a garment are made in a separate operation. An article having a lightcoloured centre such as is found in an object cut from a horn tip, the colour increasing in intensity from the centre towards the circumference, may be made by a process similar to that described above, the first deposited coloured powder being in the form of a ring T, Fig. 14, and the second - deposited white powder forming a heap W within the ring. There may be many moulds, which may be stationary, stencils and screens carrying mould-' ing powder moving in steps over the moulds. The moulding powder may be a mixture of powdered horn and hooves of animals and ureaformaldehyde synthetic resin.