Resin-forming die system, especially for melt-spinning

摘要

A resin-forming die system in which a surface lubricant with mould release properties (I) is continuously supplied to a die face (1a) provided with outlet openings (2a) for resin extrusion. The system has a feed section (5a) to supply lubricant (I) from outside, and one or more channels (3) with a width of 10-3000 microns and a depth of 10 microns or more in positions next to the outlets (2a) and with at least one end connected to the lubricant feed section (5a). Also claimed is a resin-forming process using this system which is supplied with a lubricant (I) with a viscosity of 0.0001-1 Pa.s during use and a surface tension of 0.04 N/m or less at 25 deg C. Preferably the die face (1a) has a surface roughness with a maximum height of 0.4 microns or more as measured on a profile curve over a test section of 0.25 mm. A lubricant receiver may also be fitted underneath the system, preferably with an outlet tube and seal by means of which the lubricant can be run off. The lubricant is supplied to the feed section (5a) from a source (20) via a dropper device outside the main part of the system. The system is used as a spinning die, especially for melt spinning. Lubricant (I) is an organic polysiloxane, preferably a silicone oil of formula R2-Si(R<1>)(R<3>)-(O-Si(R<7>)(R<8>)-)-OSi(R<4>)(R<6>)(R<5>) (Ia) (where R<1>-R<8> = Me, Ph or H. The preferred silicone oil is dimethyl- or methylphenyl-silicone).