Patent ID: 9409336
Filing Date: 2016-08-09
CPC Classification: B01J,B29B,B29C,B29K,B29L,C08L

Claim Text:
1. A method for preparing coated binder units, which method comprises the steps of: (a) supplying a binder material that is either bitumen or a synthetic binder having rheological and mechanical properties of bitumen, wherein the bitumen and the synthetic binder each have a characteristic softening point, and a coating material that is a polymer having a melting point of less than 200° C., to an co-extrusion device at a weight ratio of binder material-to-coating material of at least 5:1, wherein the co-extrusion device comprises an even number of pairs of inner dies and outer dies, whereby the binder material is supplied to the inner dies at a temperature above 50° C. above its characteristic softening point and not exceeding 100° C. above its characteristic softening point and the coating material is supplied to the outer dies at a temperature below its melting point; (b) co-extruding the binder material and the coating material by means of the co-extrusion device to thereby produce streams of extrudate comprising a core of the binder material coated with a layer of the coating material, wherein the layer is substantially continuous and has an average thickness of at least 10 μm; and (c) shaping the streams of extrudate into the coated binder units.