Process for making objects from mineral fillers bonded with a thermosetting resin
AssigneeStamicarbon B.V.
InventorRene L. E. van Gasse
Life of this patent
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Abstract
Three-dimensional shaped objects are made by moulding a material, a moulding material consisting of mineral fillers and a thermosetting resin with a hardener being first evenly distributed outside the mould, the assembly (sheet) that has been prepared in this way and is still pliable being transferred to the mould and subsequently subjected to pressure at an elevated temperature, with the wall of the mould being provided, at the elevated temperature, with a layer of powdery, thermosetting resin with catalyst, which resin is made to melt and polymerize, after which the pretreated moulding material is installed in the mould and subjected to pressure. While the resin is melting, a fiber layer can be applied to it.
Claims13
In a process for moulding three-dimensionally shaped article from a molding material including the steps of
- (1) forming a pliable sheet of molding material composed of a thermosetting resin, a hardener of said thermosetting resin and mineral fillers;
- (2) transferring the thus formed sheet in a pliable condition to a mold;
- and
- (3) subjecting the sheet to pressure at an elevated temperature to form a three-dimensionally shaped article,
- the improvement wherein prior to step (2)
- (a) at least a portion of the wall of the mold, under conditions of elevated temperature, is provided with at least one layer of a mixture of a powdery thermosetting resin and a catalyst for said resin,
- (b) the applied resin of step (a) is allowed to melt and is polymerized at said elevated temperature, and
- (c) the pliable sheet is inserted into the thus coated mold and subjected to pressure according to steps (2) and (3).
Dependencies are inferred from the claim text.