Matrix and method of producing said matrix
View Patent ↗The invention relates to a matrix suitable for use in the replication of a plastic element having a positive microstructure, comprising a first wear-resistant layer that is supported by a carrier element, wherein the matrix comprises a heating means for supplying electrical heat energy through the wear-resistant layer or carrier element. The invention further relates to a plastic element producing machine and a method for the manufacture of a plastic element having a surface with a positive microstructure.
1. A matrix for use in the replication of a plastic element having a positive microstructure, comprising a first wear-resistant layer, wherein said layer is supported by a carrier element having a thermal conductivity of less than 2 W/m/°K, wherein said layer consists of an electrically conducting or semi-conducting material having a resistivity of between 0.025 and 0.12 ohms×mm 2 /m, wherein said matrix is in the form of a singular structure mould cavity insert and is connected to a source of electrical heat energy via the first wear-resistant layer or a layer supporting the first wear-resistant layer by a connecting means.
2. The matrix of claim 1 , wherein the carrier element has a resistivity of less than 0.3 ohms×mm 2 /m.
3. The matrix of claim 1 , wherein the carrier element has a resistivity of less than 0.03 ohms×mm 2 /m.
4. The matrix of claim 1 , wherein the carrier element is capable of producing heat.
5. The matrix of claim 1 , wherein the electrical heat energy is supplied by applying a voltage to the electrically conducting or semi-conducting material of the first wear-resistant layer.
6. A plastic element producing machine including the matrix of claim 1 , wherein said machine is a compression moulding, an injection moulding or an embossing machine.
7. A method for the manufacture of a plastic element having a surface with a positive microstructure comprising the steps of:
(i) providing the matrix of claim 1 ; and
(ii) replicating said plastic element on said matrix while supplying heat energy to the electrically conducting or semi-conducting material of the first wear-resistant layer during the filling of the matrix mould cavity with molten plastic.
8. The method of claim 7 , wherein step (ii) is performed in a plastic element-producing machine based on replication of the matrix.
9. The method of claim 8 , where said plastic element-producing machine is a compression moulding, an injection moulding or an embossing machine.
10. The method of claim 8 , wherein said first wear layer is a metal layer.
11. The method of claim 8 , wherein said plastic element is an optical disc.
12. The matrix of claim 1 , wherein said carrier element comprises a polymer material that acts as a heat shield.
13. The matrix of claim 1 , wherein said carrier element comprises a plastic composite.
14. The matrix of claim 1 , wherein said first wear-resistant layer has a thickness ranging between 1 and 50 μm.
15. The matrix of claim 1 , wherein said first wear-resistant layer is a metal layer.
16. The matrix of claim 1 , wherein said first wear-resistant layer exposes an inverse microstructure on its surface having a depth variation ranging between 0.1 and 1000 μm.