Process and device for the manufacture of mouldings and mouldings manufactured in accordance with that process

A device for the manufacture of mouldings, comprising:

• a closable and openable mould, wherein the mould comprises a first mould half having a first mould surface and a second mould half having a second mould surface, wherein the first and second mould surfaces together define a mould cavity which can be filled with a starting crosslinkable material, wherein at least one of the first and second mould surfaces is permeable to an energy suitable to cause crosslinking of a crosslinkable material to be introduced into the mould;
• a source providing the energy;
• at least one mask fixed, constructed or arranged in, at or on one of the first and second mould halves having an energy-permeable mould surface, wherein the mask is impermeable or at least of poor permeability compared with the permeability of the energy-permeable mould surface, wherein the mask extends inwardly right up to the mould cavity and surrounds the mould cavity so as to screen all areas behind the mask with the exception of the mould cavity, wherein the mask, under irradiation of the energy in a form of a substantially parallel beam, spatially restricts impingement of the energy to an energy-impinging region, thereby crosslinking essentially only the starting crosslinkable material located inside the energy-impinging region to form a moulding having a first surface, an opposite second surface and a clean and burr-free moulding rim which does not require any subsequent mechanical processing, wherein the energy-impinging region is defined by combination of the first and second mould surfaces and an imaginary wall extending between the first and second mould surfaces and surrounding the mould cavity, wherein the imaginary wall is formed by transferring the boundary contour with the mould cavity of the mask in a two-dimensionally parallel and downwards manner from one mould surface to the other mould surface, wherein the first surface is defined by the first mould surface, the second surface is defined by the second mould surface, and partial areas of the moulding rim are defined by the imaginary wall which is defined by the boundary contour of the mask with the mould cavity.

A process for the manufacture of a crosslinked moldings, comprising the steps of:

• (a) introducing a starting crosslinkable material into a mold, wherein said mold comprises a first mold half having a first molding surface, a second mold half having a second molding surface, and at least one mask, wherein the first and second molding surfaces together define a mold cavity, wherein at least one of the first and second mould surfaces is permeable to a crosslinking energy suitable to cause the crosslinking of the starting crosslinkable material, wherein the mask is fixed, constructed or arranged in, at or on one of the first and second mould halves having an energy-permeable mould surface and is impermeable or at least of poor permeability compared with the permeability of the energy-permeable mould surface, wherein the mask extends inwardly right up to the mould cavity and surrounds the mould cavity so as to screen all areas behind the mask with the exception of the mould cavity;
• (b) providing the crosslinking energy in a form of a substantially parallel beam;
• and
• (c) irradiating with the enemy the mould containing the starting material from the mould half having the mask associated therewith so as to spatially restrict the crosslinking energy to be impinged to the mold cavity in an energy-impinging region, wherein the energy-impinging region is defined by combination of the first and second mould surfaces and an imaginary wall extending between the first and second mould surfaces and surrounding the mould cavity, wherein the imaginary wall is formed by transferring the boundary contour with the mould cavity of the mask in a two-dimensionally parallel and downwards manner from one mould surface to the other mould surface, thereby causing essentially only the starting crosslinkable material located inside the energy-impinging region to be crosslinked to a degree sufficient to form the molding capable of being released from said mold, wherein the produced molding comprises a first surface defined by the first molding surface, an opposite second surface defined by the second molding surface, and a clean and burr-free moulding rim which does not require any subsequent mechanical processing and at least partial areas of which are defined by the imaginary wall which is defined by the boundary contour of the mask with the mould cavity.