| 摘要 |
<p>1,118,912. Method for forming fibres by splitting thermoplastic film. TOSHIBA MACHINE CO. Ltd. 29 July, 1965 [13 Aug., 1964], No. 32474/65. Heading B5B. Thermoplastic film material is split to form fibres or a fine network structure using a roller having on its periphery a plurality of grooves of equal pitch and cutting edges of equal pitch disposed substantially in spiral form, the speed of the cutting roller being changeable in relation to that of the film in contact therewith, and the angle which the film makes with the cutting roller also being alterable. The cutting roller may be made to rotate in the same direction as the film travelling in contact with it, or in the case of film material which is not easily split, the roller may be rotated in a direction opposite to the direction of movement of the film. By altering the pitch of the grooves and cutting edges of the roller, the speed of the cutting roller in relation to that of the film, and the angle which the roller makes with the film, fibres of varying degrees of fineness may be obtained. A plurality of cutting rollers may be used in an apparatus according to the invention, the thermoplastic film contacting each of the rollers in turn. In one embodiment (Fig. 1) a tap-like cutting roller 3 has a plurality of lands 1 and a plurality of grooves 2, and has a rotational axis 4 so that it can be made to revolve by means of a pulley (not shown) and a belt (not shown). The lands 1 provide the cutting edges and are biased slightly towards the axial direction so that the lands present the formation of a screw thread. A thermoplastic film material 7 moves in conjunction with cutting roller 3.</p> |
