Method for shaping thermosetting resins

Claim 1

A method of extrusion-molding a thermosetting resin comprising the following steps: employing a screw-type extrusion-molding machine which comprises a screw having in sequence a feed zone, a compression zone, a metering zone, and a smooth zone, said smooth zone being in a front section of said screw, said machine further including a first cylinder portion having a heat control mechanism in areas respectively corresponding to the feed, compression, and metering zones, and a second cylinder portion having a heat-supplying capability in an area corresponding to the smooth zone, wherein said screw has a length to diameter ratio of 7 to 40, and a compression ratio of 1.0 to 5.0, a length of the smooth zone being in the range of 1D to 15D, wherein D is a diameter of the screw, wherein said employing step comprises the following steps: heating the parts of the cylinder which correspond to the compression, metering, and smooth zones of the screw to a temperature in a range of 50° to 200° C.; and molding said resin in the smooth zone; said method further comprising the step of thermosetting the resin in the smooth zone to such an extent that the resin after being extruded from the extrusion molding machine is capable of retaining its own shape, wherein said resin is selected from the group consisting of a phenolic resin, a melamine resin, and an epoxy resin.

Claim 2

A method of extrusion-molding a thermosetting resin comprising the following steps: employing a screw-type extrusion-molding machine which comprises a screw having in sequence a feed zone, a compression zone, a metering zone, and a smooth zone, said smooth zone being in a front section of said screw, said machine further including a first cylinder portion having a heat control mechanism in areas respectively corresponding to the feed, compression, and metering zones, and a second cylinder portion having a heat-supplying capability in an area corresponding to the smooth zone, wherein said screw has a length to diameter ratio of 7 to 40, and a compression ratio of 1.0 to 5.0, a length of the smooth zone being in the range of 1D to 15D, wherein D is a diameter of the screw, wherein said employing step comprises the following steps: heating the parts of the cylinder which correspond to the compression, metering, and smooth zones of the screw to a temperature in a range of 50° to 200° C.; and molding said resin in the smooth zone; said method further comprising the step of thermosetting the resin in the smooth zone to such an extent that the resin after being extruded from the extrusion molding machine is capable of retaining its own shape, wherein said resin is selected from the group consisting of a phenolic resin, a melamine resin, and an epoxy resin.