US3788503A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for producing biaxially molecule-oriented poly-{68 -caproamide resin film
Assignee: Kohjin Holdings Co Ltd
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Filing: 1970-12-10
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Granted: 1974-01-29
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Expires: 1990-12-10
Abstract
Abstract A biaxially molecule-oriented film of poly- Epsilon -caproamide resin having an improved dimensional stability and surface slip characteristic is prepared by extruding the molten resin downward through an annular die, quenching and solidifying the extruded film by means of an internally liquid-cooled, cooling mandrel having a specific shape to form a substantially amorphous, nonstretched tubular film substantially free of any hydrogen bond, allowing the thus obtained film to come in contact with a heating gas while heating the film at a temperature of from 45* to 70*C and keeping a water content of the film at not more than 2 % based on the weight of the film, biaxially stretching the heated film simultaneously at a stretching ratio of 2 to 4 in both longitudinal and transversal directions by introducing a pressurized gas into the tubular film between a low speed feeding section and a high speed take-up section of the film, and heatsetting the thus stretched film while keeping a water content of the film at least at 1 % based on the weight of the film to an equilibrium water absorption content in water.
Inventors
- 👤 H Hirose
- 👤 A Skkita
- 👤 M Kito
- 👤 M Tsubosaki
- 👤 M Sugiyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:53
CPC Classifications
B; B29; B29C; B29C55/00; B29C55/28; B29C35/00; B29C48/00; B29C48/001; B29C48/0018; B29C48/0019; B29C48/03; B29C48/09; B29C48/10; B29K; B29K2077/00; Y; Y10; Y10S; Y10S264/00; Y10S264/90; Y10S264/902
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
7 words
being substantially free of any hydrogen bond,
Claim 2
Dependent Claim
7 words
being substantially free of any hydrogen bond,
Claim 3
Dependent Claim
7 words
being substantially free of any hydrogen bond,
Claim 4
Dependent Claim
32 words
The method of claim 1 wherein the stretching ratio of step (d) and the temperature of step (c) are correlated so as to fall within the cross-hatched area II of FIG. 3.
Claim 5
Dependent Claim
7 words
being substantially free of any hydrogen bond,
Claim 6
Dependent Claim
4 words
being substantially unstretched, and
Claim 7
Independent Claim
22 words
The method which comprises a. introducing into a stretching zone a tubular film composed of a poly- epsilon -caproamide resin, said resin
Claim 8
Dependent Claim
4 words
being substantially unstretched, and
Claim 9
Dependent Claim
4 words
being substantially unstretched, and
Claim 10
Dependent Claim
4 words
being substantially unstretched, and
Claim 11
Dependent Claim
26 words
A process according to claim 3 wherein the resin set forth in step (a) has a water content of not more than 1 percent by weight.
Claim 12
Dependent Claim
65 words
having a water content of not more than 2% by weight, b. biaxially stretching said tubular film after introduction into said stretching zone, c. maintaining said tubular film at a temperature within the range of 45*C - 70*C during said biaxial stretching step by contacting said tubular film with a heated gas, and d. recovering a biaxially molecule-oriented tubular film of poly- epsilon -caproamide resin.
Claim 13
Dependent Claim
100 words
having a water content of not more than 2 percent by weight, b. biaxially stretching said tubular film after introduction into said zone, c. maintaining said tubular film at a temperature within the range of 45*C - 70*C. during said biaxial stretching step by contacting said tubular film with a heated gas, and d. heat setting the biaxially stretched film at a water content of 1 - 9 percent by weight based on the weight of the film, and e. recovering a biaxially molecule-oriented tubular film of poly- epsilon -caproamide resin having improved dimensional stability and improved surface slip characteristics.
Claim 14
Dependent Claim
214 words
having a water content of not more than 1 percent by weight, d. introducing said tubular film into a stretching zone and biaxially stretching the film at a stretching ratio of between 2 and 4 by introducing a gas under pressure into the interior of the tubular film, e. maintaining said tubular film at a temperature within the range between 50* and 60* C. during said biaxial stretching step by introducing said tubular film into a heating zone that extends in the direction of travel of the film, the length of said heating zone being not more than five times the diameter of the non-stretched tubular film, and contacting said tubular film with a heated gas, said heating gas being blown in a direction almost perpendicular to the travelling direction of the film from a point near the starting point of stretching, and at the same time another heating gas is blown along the travelling direction of the film in advance of the starting point of stretching, f. heat setting the biaxially stretched film at a water content of 1 - 9 percent by weight based on the weight of the film, and g. recovering a biaxially molecule-oriented tubular film of poly- epsilon -caproamide resin having improved dimensional stability and improved surface slip characteristics.
Claim 15
Dependent Claim
99 words
having a water content of not more than 2 percent by weight, d. introducing said tubular film into a stretching zone and biaxially stretching the film at a stretching ratio of between 2 and 4 by introducing a gas under pressure into the interior of the tubular film, e. maintaining said tubular film at a temperature within the range of 45*C - 70*C during said biaxial stretching step by contacting said tubular film with a heated gas, and f. recovering a biaxially molecule-oriented tubular film of poly- epsilon -caproamide resin having improved dimensional stability and improved surface slip characteristics.
Claim 16
Dependent Claim
41 words
A method according to claim 3 wherein said biaxial stretching is carried out simultaneously in both the longitudinal and transversal directions at a stretching ratio of 2 to 4 by introducing a pressurized gas into the interior of the tubular film.
Claim 17
Dependent Claim
20 words
A method according to claim 3 wherein said stretching is carried out at a temperature between about 50*C and 60*C.
Claim 18
Dependent Claim
45 words
A method according to claim 3 wherein said heating is carried out in a heating zone that extends in the direction of travel of the film, the length of said heating zone being not more than five times the diameter of the non-stretched tubUlar film.
Claim 19
Dependent Claim
23 words
A method according to claim 7 wherein said heating zone has a diameter which is 2 to 3 times the non-stretched tubular film.
Claim 20
Dependent Claim
24 words
A method according to claim 5 wherein the point where the heating gas first contacts the tubular film establishes the starting point of stretching.
Claim 21
Dependent Claim
58 words
A method according to claim 9 wherein the heating gas is blown in a direction almost perpendicular to the travelling direction of the film from a point near the starting point of stretching and at the same time another heating gas is blown along the travelling direction of the film in advance of the starting point of stretching.
Claim 22
Independent Claim
22 words
The method which comprises a. introducing into a stretching zone a tubular film composed of a poly- epsilon -caproamide resin, said resin
Claim 23
Dependent Claim
29 words
A method according to claim 11 wherein the heat setting is carried out at a water content of from 2 percent to an equilibrium water absorption content in water.
Claim 24
Independent Claim
78 words
The method which comprises: a. extruding a molten tubular film of poly- epsilon - epsilon -caproamide resin, b. quenching and cooling said molten extruded film by passing it in sliding contact with the exterior surface of an internally cooled mandrel of circular cross section, the radius of curvature of the tubular film that first contacts the exterior surface of the mandrel being not more than 5 mm, c. withdrawing a tubular film from around said mandrel, said film
Claim 25
Dependent Claim
34 words
A method according to claim 13 wherein the tubular film is also cooled as it passes around said mandrel by a cooling fluid that flows in contact with the interior of the tubular film.
Claim 26
Dependent Claim
30 words
A method according to claim 13 wherein the exterior of the tubular film is contacted with a cooling fluid as the tubular film passes over the exterior of the mandrel.
Claim 27
Dependent Claim
29 words
A method according to claim 13 wherein the exterior of the tubular film is contacted with a stream of cooled air as the tubular film passes over the mandrel.
Claim 28
Dependent Claim
40 words
A method according to claim 13 wherein the biaxially molecule-oriented film of poly- epsilon -caproamide after stretching is heat-set while maintaining the water content of the film between 1 percent and 9 percent based on the weight of the film.
References Cited (Backward Citations)
US2987767A
Cited
US2968065A
Cited
US3313870A
Cited
US3300555A
Cited
US3304352A
Cited
US3514460A
Cited
US3280079A
Cited
US3400184A
Cited
US3502766A
Cited
US3449299A
Cited
US3426113A
Cited
US3560606A
Cited
US3651200A
Cited
US3632728A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-28 | 1977-07-30 | 1978-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-28 | 1981-07-30 | 1982-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-28 | 1985-07-30 | 1986-01-29 | $7700.00 | Window Closed / Lapsed |