Abstract In melt spinning a crystalline plastic material such as, for example, nylon 6, molten filaments discharged through the spinneret are drafted at a mathematical draft of not less than 3 and, while being so drafted in their molten state, are abruptly cooled to a temperature below -30 DEG C, whereby the microbrownian motion of the molecules in the filaments is frozen while the molecules in the filaments are retained in a specific oriented state. When the filaments in which the molecules are oriented in a fixed direction and hence the chains of molecules are in a readily stretchable state are further subjected to a stretching treatment at a temperature at which the microbrownian motion of molecules remains frozen, there are produced filaments possessed of mechanical strengths far exceeding those exhibited by filaments which are spun and stretched by the conventional method.
A method for the manufacture of filaments of crystalline plastic selected from the group consisting essentially of polyamide, polyolefin and polyester which comprises the steps of 1. forming molten filaments of the crystalline plastic by melt spinning said crystalline plastic from a spinneret; 2. drafting said molten filaments at a mathematical draft of from 3 to 1000; 3. instantaneously cooling said drafted, molten filaments to a temperature from -30° to -100°C, thereby forming amorphous, orientable. glassy filaments;
Claim 2
Independent Claim
77 words
A method for the manufacture of filaments of crystalline plastic selected from the group consisting essentially of polyamide, polyolefin and polyester which comprises the steps of 1. forming molten filaments of the crystalline plastic by melt spinning said crystalline plastic from a spinneret; 2. drafting said molten filaments at a mathematical draft of from 3 to 1000; 3. instantaneously cooling said drafted, molten filaments to a temperature from -30° to -100°C, thereby forming amorphous, orientable. glassy filaments;
Claim 3
Dependent Claim
44 words
stretching said amorphous, orientable, glassy filaments from 4 to 8 times at 10° to -80° C; and 5. elevating the temperature of the filaments of step (4) so as to induce crystallization wherein the method of manufacture of steps (1) - (5) is continuous.
Claim 4
Dependent Claim
44 words
stretching said amorphous, orientable, glassy filaments from 4 to 8 times at 10° to -80° C; and 5. elevating the temperature of the filaments of step (4) so as to induce crystallization wherein the method of manufacture of steps (1) - (5) is continuous.
Claim 5
Dependent Claim
13 words
The method of claim 1, wherein the filaments of step (5) are stretched.