| 摘要 |
533,412. Extrusion machines. SPONCEL, Ltd. Nov. 6, 1939, No. 29452. Convention date, Feb. 6. [Class 87 (ii)] Artificial sponges, as described in Specification 454,190, are moulded in a screw extrusion press having a pyramidal die 3 which is twisted in a direction opposite to that of the rotation of the screw to effect disorientation of the material, the angle of twist being preferably between 15 and 45 degrees. |
