| 摘要 |
Pre-polymeric formulations suitable for producing polymeric rule dies comprise (a) at least one pre-polymer e.g. of the acrylate type, (b) a photoinitiator selected to polymerise said pre-polymer, and (c) a thickening agent, where the photoinitiator and thickening agent are mixed with the pre-polymer. The formulation has the following rheological properties at 25 degrees C: (i) Grest > 3,000 Pascal (Pa) and (ii) G exhibits a value of at least 2,500 Pa after being subjected to an oscillation stress of 300 Pa for 20 seconds, within 7 seconds of an abrupt relaxation of said stress, G being a storage modulus of the formulation, Grest being a storage modulus of the formulation at a pressure of 40 Pa, at rest; the formulation having a baseline density �baseline, a bulk density �bulk, and a differential density Δ�, said differential density defined by; Δ� = �baseline - �bulk said differential density being at least 0.01. |
