US4435241A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of extruding laminated film
Assignee: Equistar Chemicals LP
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Filing: 1967-05-26
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Granted: 1984-03-06
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Expires: 1987-05-26
Abstract
Abstract A lamination die apparatus; a method of extruding; and extruded products where two or more laminarly flowing plastic layers are joined in front of an extrusion nozzle, and are simultaneously extruded through the extruded nozzle. The laminarly joined flows are caused to diverge before being extruded through the extrusion orifice. The various layers may be of the same or different material. The layers variously include polyethylene, polypropylene, polyvinylchloride and can have electrical or magnetic particles mixed therein to impart electrical or magnetic characteristics to the film. The die structure may be for blowing tubular film or for the extrusion of flat film. The flat die includes a diverter for diverting a main stream into at least two paths of laminar flow and injecting a central plastic fluid between these two paths.
Inventors
- 👤 Herbert O. Corbett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:44
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/03; B29C48/07; B29C48/08; B29C48/09; B29C48/10; B29C48/14; B29C48/147; B29C48/1472; B29C48/16; B29C48/18; B29C48/21; B29C48/25; B29C48/255; B29C48/2556; B29C48/30; B29C48/305; B29C48/307; B29C48/32; B29C48/335; B29C48/337; B29C48/36; B29C48/49; B29C2791/00; B29C2791/004; B29C2791/007
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
252 words
A method for the extrusion of a composite stream of heat-plastified synthetic resinous material in a sheet-like configuration wherein the composite stream comprises at least three layers of diverse synthetic resinous material, the method comprising: providing a first stream of heat-plastified synthetic resinous material to a restraining configuration, the restraining configuration having a generally slot-like extrusion orifice, dividing the first stream of heat-plastified synthetic resinous material into a first substream and a second substream having a generally planar configuration, providing a second stream of heat-plastified synthetic resinous material, the second stream having a generally planar configuration and a width substantially less than the first and second substreams, positioning the first and second substreams on either side of the second stream, subsequently, passing the first and second substreams and the second stream through an elongate slot-like extrusion orifice, the second stream being encapsulated within the first and second substreams in the composite stream, the second stream being generally coextensive with the resultant extruded sheet, the improvement which comprises restricting the flow of the first stream generally at the point where it is divided into the first and second substreams and introducing between the first and second substreams the second stream in a generally planar configuration generally parallel to the first and second substreams and having a dimension substantially less in width than the first and second substreams, and passing the first and second substreams and the second stream to the extrusion orifice by means of a tapering configuration which converges toward the orifice.
Claim 2
Independent Claim
252 words
A method for the extrusion of a composite stream of heat-plastified synthetic resinous material in a sheet-like configuration wherein the composite stream comprises at least three layers of diverse synthetic resinous material, the method comprising: providing a first stream of heat-plastified synthetic resinous material to a restraining configuration, the restraining configuration having a generally slot-like extrusion orifice, dividing the first stream of heat-plastified synthetic resinous material into a first substream and a second substream having a generally planar configuration, providing a second stream of heat-plastified synthetic resinous material, the second stream having a generally planar configuration and a width substantially less than the first and second substreams, positioning the first and second substreams on either side of the second stream, subsequently, passing the first and second substreams and the second stream through an elongate slot-like extrusion orifice, the second stream being encapsulated within the first and second substreams in the composite stream, the second stream being generally coextensive with the resultant extruded sheet, the improvement which comprises restricting the flow of the first stream generally at the point where it is divided into the first and second substreams and introducing between the first and second substreams the second stream in a generally planar configuration generally parallel to the first and second substreams and having a dimension substantially less in width than the first and second substreams, and passing the first and second substreams and the second stream to the extrusion orifice by means of a tapering configuration which converges toward the orifice.
Claim 3
Dependent Claim
16 words
The method of claim 4 wherein the first stream is divided by a generally cylindrical configuration.
Claim 4
Dependent Claim
17 words
The method of claim 2 wherein the generally cylindrical configuration supplies a generally centrally disposed second stream.
Claim 5
Dependent Claim
20 words
The method of claim 3 wherein the cylindrical configuration is supplied with the second stream in a generally axial manner.
Claim 6
Dependent Claim
23 words
The method of claim 1 wherein the first stream is supplied to the restraining configuration at a location remote from the extrusion orifice.
Claim 7
Dependent Claim
33 words
The method of claim 1 including the step of varying the restriction of the first stream to obtain the desired degree of splitting of the second stream between the first and second substreams.
Claim 8
Dependent Claim
137 words
A process for the extrusion of multiple-layered sheeting of thermoplastic resin, said process comprising the steps of (a) joining in a tube, at least two laminar-flow streams of molten thermoplastic resin into a combined stream of molten thermoplastic resin which has a sharply defined juncture between the components of the combined stream, (b) passing said combined stream of molten thermoplastic resin into a manifold of a sheeting extrusion die the juncture plane(s) between each of the individual molten thermoplastic resin components within the manifold being parallel to the principal direction of flow of the resin as it passes from the manifold and takes on the shape of sheeting, and (c) whereby a multiple-layered sheeting wherein the individual layers of thermoplastic resin are of substantially uniform thickness over substantially all of the width of the sheeting is formed.
Claim 9
Dependent Claim
137 words
A process for the extrusion of multiple-layered sheeting of thermoplastic resin, said process comprising the steps of (a) joining in a tube, at least two laminar-flow streams of molten thermoplastic resin into a combined stream of molten thermoplastic resin which has a sharply defined juncture between the components of the combined stream, (b) passing said combined stream of molten thermoplastic resin into a manifold of a sheeting extrusion die the juncture plane(s) between each of the individual molten thermoplastic resin components within the manifold being parallel to the principal direction of flow of the resin as it passes from the manifold and takes on the shape of sheeting, and (c) whereby a multiple-layered sheeting wherein the individual layers of thermoplastic resin are of substantially uniform thickness over substantially all of the width of the sheeting is formed.
Claim 10
Dependent Claim
40 words
The process as defined in claim 7, said joining in a tube comprising combining the flow of at least two laminar-flow streams so that the resultant combined stream has at least two substantially discrete layers with no mixing occuring therebetween.
Claim 11
Dependent Claim
38 words
The process as defined in claims 7 or 8, said passing said combined stream comprising allowing the laminar-flow streams to flow into the extrusion die in a uniform configuration so that the separate laminar-flow streams remain coextensive therein.
Claim 12
Dependent Claim
108 words
A process for extruding multiple thermoplastic resins, comprising: (a) supplying separate streams of thermoplastic resins into an extrusion apparatus and causing the streams to combine therein in a flowing manner to form an interface between said streams; (b) causing the combined streams to flow laminarly without any mixing across the interface between the thermoplastic resin streams so as to maintain the physical integrity of each stream in said combined stream; (c) altering the overall cross-sectional geometric configuration of the combined stream within a forming die thereby providing a thermoplastic resin extrudate exiting said die, having a coextensive, integral, and uniform configuration of said thermoplastic resins in said extrudate.
Claim 13
Dependent Claim
108 words
A process for extruding multiple thermoplastic resins, comprising: (a) supplying separate streams of thermoplastic resins into an extrusion apparatus and causing the streams to combine therein in a flowing manner to form an interface between said streams; (b) causing the combined streams to flow laminarly without any mixing across the interface between the thermoplastic resin streams so as to maintain the physical integrity of each stream in said combined stream; (c) altering the overall cross-sectional geometric configuration of the combined stream within a forming die thereby providing a thermoplastic resin extrudate exiting said die, having a coextensive, integral, and uniform configuration of said thermoplastic resins in said extrudate.
Claim 14
Dependent Claim
19 words
A process as defined in claim 10, said thermoplastic streams forming a layered configuration having a substantially laminar flow.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-03-06 | 1987-09-05 | 1988-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-03-06 | 1991-09-05 | 1992-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-03-06 | 1995-09-05 | 1996-03-06 | $7700.00 | Window Closed / Lapsed |