Patent US2083356A successfully refreshed from Google Patents.
Patent US4863653A successfully refreshed from Google Patents.
US4863653A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of producing thermoplastic resin sheet and equipment therefor
Assignee: Idemitsu Petrochemical Co Ltd
•
Filing: 1988-02-23
•
Granted: 1989-09-05
•
Expires: 2008-02-23
Abstract
Abstract This invention relates to a process of producing a thermoplastic resin sheet and equipment therefore. The equipment includes a first extruder of a high kneading type, a second extruder of a low kneading type and an extrusion die. A film-shaped resin extruded from the extrusion die is cooled by a cooling device, to thereby obtain the resin sheet. Additionally, a difference between pressures at the outlets of the first and second extruders is detected, and, in response to this difference between the pressures thus detected, the operating conditions of the first extruder are automatically controlled.
Inventors
- 👤 Toyokazu Takubo
- 👤 Atsushi Fujii
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 11:13
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/88; B29C48/919; B29C48/03; B29C48/07; B29C48/08; B29C48/36; B29C48/365; B29C48/37; B29C48/375; B29C48/38; B29C48/387; B29C48/395; B29C48/91; B29C48/911; B29C48/92; B29C37/00; B29C2037/96; B29C2948/00; B29C2948/92; B29C2948/92009; B29C2948/92019; B29C2948/92323; B29C2948/92342; B29C2948/92361; B29C2948/9238; B29C2948/92504; B29C2948/92514; B29C2948/9258; B29C2948/9259; B29C2948/926; B29C2948/92704; B29C2948/92819; B29C2948/92838; B29C2948/92857; B29C2948/92876; B29C2948/92885; B29C2948/92895; B29C2948/92952; B29C2948/92971
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
120 words
A process for producing a thermoplastic resin sheet comprising the steps of kneading the thermoplastic resin in a first extruder of a high kneading type and extruding the thermoplastic resin in a molten state; introducing the molten resin into a gear pump in which the molten resin is additionally kneaded; supplying the molten resin from the gear pump to a second extruder of a low kneading type; extruding a molten film-shaped resin from said second extruder through a die located at the outlet of said second extruder; and introducing said molten film-shaped resin through a slit, at an inlet of which cooling water flows in such a manner that it does not stagnate and uniformly cools said molten film-shaped resin.
Claim 2
Dependent Claim
120 words
A process for producing a thermoplastic resin sheet comprising the steps of kneading the thermoplastic resin in a first extruder of a high kneading type and extruding the thermoplastic resin in a molten state; introducing the molten resin into a gear pump in which the molten resin is additionally kneaded; supplying the molten resin from the gear pump to a second extruder of a low kneading type; extruding a molten film-shaped resin from said second extruder through a die located at the outlet of said second extruder; and introducing said molten film-shaped resin through a slit, at an inlet of which cooling water flows in such a manner that it does not stagnate and uniformly cools said molten film-shaped resin.
Claim 3
Dependent Claim
48 words
A process of producing a thermoplastic resin sheet as set forth in claim 1, wherein said first extruder of the high kneading type has a compression ratio of 2 or more and said second extruder of the low kneading type has a compression ratio of less than 2.
Claim 4
Dependent Claim
38 words
A process of producing a thermoplastic resin sheet as set forth in claim 1, wherein said first extruder has a compression ratio of 3 or more and the second extruder has a compression ratio of 1.5 or less.
Claim 5
Dependent Claim
45 words
A process of producing a thermoplastic resin sheet as set forth in claim 1, wherein pressures at the outlets of said first and second extruders are detected, respectively, and a screw speed of said first extruder is controlled in response to the results of detections.
Claim 6
Independent Claim
96 words
An apparatus for producing a thermoplastic resin sheet comprising: a first extruder; a second extruder serially connected to said first extruder through a pipe means located therebetween; a gear pump located on an intermediate portion of said pipe means; a die provided on the extrusion side of said second extruder through which a molten film-shaped resin is extruded; and a cooling device for cooling said molten film-shaped resin, said cooling device being provided with a slit through which said molten film-shaped resin passes and cooling water flows so as to uniformly cool said molten film-shaped resin.
Claim 7
Independent Claim
96 words
An apparatus for producing a thermoplastic resin sheet comprising: a first extruder; a second extruder serially connected to said first extruder through a pipe means located therebetween; a gear pump located on an intermediate portion of said pipe means; a die provided on the extrusion side of said second extruder through which a molten film-shaped resin is extruded; and a cooling device for cooling said molten film-shaped resin, said cooling device being provided with a slit through which said molten film-shaped resin passes and cooling water flows so as to uniformly cool said molten film-shaped resin.
Claim 8
Dependent Claim
41 words
An apparatus for producing a thermoplastic resin sheet and the like as set forth in claim 5, wherein said first extruder has a compression ratio of 3 or more and said second extruder has a compression ratio of 1.5 or less.
Claim 9
Dependent Claim
71 words
An apparatus for producing a thermoplastic resin sheet as set forth in claim 5, wherein said first and second extruders each include a screw and a cylinder, and a ratio L/D between the total length L and the diameter D of the screw of said first extruder is 10-30, and a ratio L/D between the total length L and the diameter D of the screw of said second extruder is 5-40.
Claim 10
Dependent Claim
50 words
An apparatus for producing a thermoplastic resin sheet as set forth in claim 7, wherein a molten resin uniform kneading section formed of a torpedo, a Dulmage head or the like is provided in the intermediate portion and/or on the forward end portion of the screw of said first extruder.
Claim 11
Dependent Claim
34 words
An apparatus for producing a thermoplastic resin sheet as set forth in claim 8, wherein a clearance formed between said uniform kneading section and said cylinder is 1/150-1/20 times the diameter of said screw.
Claim 12
Dependent Claim
46 words
An apparatus for producing a thermoplastic resin sheet as set forth in claim 5, wherein pressures at the outlets of said first and second extruders are detected, respectively, and a screw speed of said first extruder is controlled in response to the results of the detections.
Claim 13
Dependent Claim
59 words
An apparatus for producing a thermoplastic resin sheet as set forth in claim 5, wherein pressure detectors are provided between said gear pump and said second extruder, and at the outlet of resin extrusion of said second extruder, and further, a controller for maintaining a difference between pressures detected by said pressure detectors at a constant value is provided.
Claim 14
Dependent Claim
150 words
A process for producing a thermoplastic resin sheet comprising the steps of kneading the thermoplastic resin in a first extruder having a compression ratio of 2 or more and extruding the thermoplastic resin in a molten state; introducing the molten resin into a gear pump in which the molten resin is additionally kneaded; supplying the molten resin from the gear pump to a second extruder having a compression ratio of less than 2, maintaining the difference in pressures at the discharge of the gear pump and the outlet of the second extruder at a constant amount; extruding a molten film-shaped resin from said second extruder through a die located at the outlet of the second extruder; and introducing said molten film-shaped resin through a slit, at an inlet of which cooling water flows in such a manner that it does not stagnate and uniformly cools said molten film shaped resin.
Claim 15
Dependent Claim
150 words
A process for producing a thermoplastic resin sheet comprising the steps of kneading the thermoplastic resin in a first extruder having a compression ratio of 2 or more and extruding the thermoplastic resin in a molten state; introducing the molten resin into a gear pump in which the molten resin is additionally kneaded; supplying the molten resin from the gear pump to a second extruder having a compression ratio of less than 2, maintaining the difference in pressures at the discharge of the gear pump and the outlet of the second extruder at a constant amount; extruding a molten film-shaped resin from said second extruder through a die located at the outlet of the second extruder; and introducing said molten film-shaped resin through a slit, at an inlet of which cooling water flows in such a manner that it does not stagnate and uniformly cools said molten film shaped resin.
References Cited (Backward Citations)
US3148231A
Cited
US3261056A
Cited
US3467743A
Cited
US3860220A
Cited
US3764118A
Cited
US4117063A
Cited
US4134714A
Cited
GB2053013A
Cited
US4452750A
Cited
EP0079012A1
Cited
JPS58203018A
Cited
JPS595044A
Cited
DE3316838A1
Cited
US4548778A
Cited
US4666649A
Cited
FR2585282A1
Cited
US4729666A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-09-04 | 1993-03-06 | 1993-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-09-04 | 1997-03-06 | 1997-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-09-04 | 2001-03-06 | 2001-09-05 | $7700.00 | Window Closed / Lapsed |