Abstract: A mould for manufacturing disc-like objects including at least two mould parts which are mutually movable between a closed position in which they bound a mould cavity, which mould cavity is connected to an injection conduit for admitting heated, plasticized plastic under pressure into said mould cavity, and an opened position in which a disc-like object can be removed. The mould also has a device for removing a central portion from a disc-like object to form a central hole present therein, which device comprises a cylindrical part which is movable in axial direction in the closed situation of the mould cavity. The mould has the feature that at least one of the two mould parts is tempered only in the middle zone of the mould cavity for tempering the inflowing plastic during the inflow thereof via the pressure line and thus during the filling of the mould cavity.

Abstract: An injection mould for manufacturing plastic objects generally includes: two mould parts mutually movable between a closed position and an open position, which mould parts bound in closed position a mould cavity into which in the closed position heated plasticized plastic can be injected by means of supply means, wherein one flat end surface of the mould cavity carries a mechanical pattern, which pattern corresponds with the information for arranging on an information carrier to be manufactured, wherein at least a part of the surfaces is provided with a coating not containing TiN and which reduces a coefficient of friction of the relevant surface to a value which amounts to a maximum of 60% of the value obtainable a coating of TiN; wherein at least one of the cylindrical inner surface and the cylindrical outer surface is provided with the coating.

Abstract: An auxiliary device is intended to be added to an injection moulding device for manufacturing disc-like information carriers. The injection moulding device comprises a mould having two mold parts which in a closed situation bound a mould cavity. An insert plate can be position against an end wall of the mould cavity, on which plate is found the information to be recorded onto the information carrier. Received in a supply holder are insert plates which can be transported by a mechanical device from and to the end wall. Positioning of the insert plates by the mechanical device takes place such that each insert plate is brought into a convex state, is placed with its central zone against the end wall and the convex form is then removed for stable positioning of the insert plate in flat state. The desired centering is thus achieved in simple manner, while friction between the insert plate and the wall is essentially prevented.