Patent US4470943A successfully refreshed from Google Patents.
US4470943A
Expired / Lapsed
US
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Low friction plastic track and extrusion process
Assignee: Mead Corp
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Filing: 1983-07-05
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Granted: 1984-09-11
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Expires: 2003-07-05
Abstract
Abstract An elongated plastic track for use in a gravity feed display is extruded from a mixture of high impact polystyrene and dimethylpolysiloxane.
Inventors
- 👤 Allen D. Preis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:10
CPC Classifications
C; C08; C08L; C08L51/00; C08L51/04
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
116 words
A process for making an elongated plastic track for use in a gravity feed display device, said track having a low coefficient of friction on at least one of its surfaces, comprising the steps of (a) mixing from 95.0 to 99.5 percent by weight of high impact polystyrene with 0.5 to 5.0 percent by weight of dimethylpolysiloxane fluid having a viscosity of between 20,000 and 40,000 centistokes so that the dimethylpolysiloxane is well dispersed in said high impact polystyrene, (b) extruding the mixture formed in (a) so as to form a track of the desired shape, and (c) thereafter burnishing said one surface of said track to decrease the coefficient of friction on said one surface.
Claim 2
Dependent Claim
116 words
A process for making an elongated plastic track for use in a gravity feed display device, said track having a low coefficient of friction on at least one of its surfaces, comprising the steps of (a) mixing from 95.0 to 99.5 percent by weight of high impact polystyrene with 0.5 to 5.0 percent by weight of dimethylpolysiloxane fluid having a viscosity of between 20,000 and 40,000 centistokes so that the dimethylpolysiloxane is well dispersed in said high impact polystyrene, (b) extruding the mixture formed in (a) so as to form a track of the desired shape, and (c) thereafter burnishing said one surface of said track to decrease the coefficient of friction on said one surface.
Claim 3
Dependent Claim
18 words
An elongated plastic track for use in a gravity feed display device produced in accordance with claim 1.
References Cited (Backward Citations)
US3900548A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-09-11 | 1988-03-12 | 1988-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-09-11 | 1992-03-12 | 1992-09-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-09-11 | 1996-03-12 | 1996-09-11 | $7700.00 | Window Closed / Lapsed |