| 摘要 |
The present invention concerns a method of producing a film material comprising the steps of creating at least a first, a second and a third mixture, leading each one of the mixtures to a co-extrusion die (1,10) and co-extruding the mixtures through the die (1,10) in order to produce a co-extruded film containing at least a first (5), a second (6) and a third (7) layer respectively. At least the mentioned second mixture comprises a blowing agent at the same time as the mentioned second mixture forms the mentioned second (6) layer in the co-extruded film. The mentioned first mixture comprises particles (8) each one of which being, in each direction, of a thickness which is larger than the thickness of the mentioned first (5) layer without the particles (8) meaning that the particles (8), through the expansion of the blowing agent in the mentioned second (6) layer, being pressed out upon the surface of the mentioned first (5) layer and creating unevennesses in the surface layer there. The present invention also concerns an abrasive material produced in accordance with the method. |
