Patent US4488918A successfully refreshed from Google Patents.
US4488918A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Non-slip plastic film
Assignee: Wiik and Hoglund AB Oy
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Filing: 1983-05-27
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Granted: 1984-12-18
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Expires: 2003-05-27
Abstract
Abstract This invention discloses a plastic film having a non-slip surface comprising spaced random patterns of rigid peaks and ridges formed by a second thermo-plastic layer coextruded with and bonded to the plastic film and rupturing the second layer during expansion.
Inventors
- 👤 Jarl-Erik Jofs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 08:28
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/03; B29C48/13; B29C48/09; B29C48/10; B29C48/12; B29C48/16; B29C48/18; B29C48/21; B29C48/25; B29C48/30; B29C48/32; B29C48/335; B29C48/337; B29C48/338; B32; B32B; B32B27/00; B32B27/06; B32B27/08; B32B27/32; B32B7/00; B32B7/02; B32B7/022; B29C48/001; B29C48/0017; B29C48/0018; B29C48/0019; B29K; B29K2105/00; B29K2105/04; B29K2105/06; B29K2105/16; B29K2995/00; B29K2995/0037; B29K2995/0072; B29L; B29L2023/00; B32B2307/00; B32B2307/70; B32B2307/72; B32B2307/744; B32B2323/00; B32B2323/04; B32B2323/046; Y; Y10; Y10T; Y10T156/00; Y10T156/10; Y10T156/1052; Y10T156/108; Y10T428/00; Y10T428/24; Y10T428/24355; Y10T428/24479; Y10T428/24612
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
156 words
A method of making a film of plastic material with a non-slip surface having a coefficient of friction of at least 0.45 comprising the steps of: extruding a first layer of plastic film having a predetermined capability to resist tearing and rupturing upon stretching; and simultaneously coextruding therewith a second layer of plastic material having a predetermined lesser capability to resist rupture on stretching than said first layer; and coextruding said second layer so that said second layer is bonded, at least at a multiplicity of spots, to said first layer; expanding and coextruded layers after extrusion so as to cause the rupture of said second layer into a random pattern of high, hard, sharp peaks and ridges; said second layer being formed of a high elasticity thermoplastic material having a melt flow index in the plastic-elastic state at least as low as 1.0, and having a high density in the range of 0.920 to 0.960.
Claim 2
Independent Claim
156 words
A method of making a film of plastic material with a non-slip surface having a coefficient of friction of at least 0.45 comprising the steps of: extruding a first layer of plastic film having a predetermined capability to resist tearing and rupturing upon stretching; and simultaneously coextruding therewith a second layer of plastic material having a predetermined lesser capability to resist rupture on stretching than said first layer; and coextruding said second layer so that said second layer is bonded, at least at a multiplicity of spots, to said first layer; expanding and coextruded layers after extrusion so as to cause the rupture of said second layer into a random pattern of high, hard, sharp peaks and ridges; said second layer being formed of a high elasticity thermoplastic material having a melt flow index in the plastic-elastic state at least as low as 1.0, and having a high density in the range of 0.920 to 0.960.
Claim 3
Dependent Claim
62 words
A method of making a film of plastic material with a non-slip surface having a co-efficient of friction of at least 0.50 comprising the steps as defined in claim 1 in which said second layer has a melt flow index in the plastic-elastic state at least as low as 0.3, and having a high density in the range of 0.920 to 0.960.
Claim 4
Dependent Claim
63 words
A method of making a film of plastic material with a non-slip surface having a co-efficient of friction of at least as high as 0.60 comprising the steps of claim 1 in which said second layer has a melt flow index in the plastic-elastic state at least as low as 0.14, and having a high density in the range of 0.920 to 0.960.
Claim 5
Dependent Claim
32 words
A method as claimed in claim 1 in which the capability of said second layer to resist rupture is reduced by impregnating the said second layer with inclusions prior to expanding same.
Claim 6
Dependent Claim
32 words
A method as claimed in claim 2 in which the capability of said second layer to resist rupture is reduced by impregnating the said second layer with inclusions prior to expanding same.
Claim 7
Dependent Claim
32 words
A method as claimed in claim 3 in which the capability of said second layer to resist rupture is reduced by impregnating the said second layer with inclusions prior to expanding same.
Claim 8
Dependent Claim
14 words
A method as claimed in claim 4 in which said inclusions are powdered particles.
Claim 9
Dependent Claim
14 words
A method as claimed in claim 5 in which said inclusions are powdered particles.
Claim 10
Dependent Claim
14 words
A method as claimed in claim 6 in which said inclusions are powdered particles.
Claim 11
Dependent Claim
14 words
A method as claimed in claim 4 in which said inclusions are gas bubbles.
Claim 12
Dependent Claim
14 words
A method as claimed in claim 5 in which said inclusions are gas bubbles.
Claim 13
Dependent Claim
14 words
A method as claimed in claim 6 in which said inclusions are gas bubbles.
Claim 14
Dependent Claim
26 words
A method as claimed in claim 10 in which said bubbles are formed by mixing compressed or condensed freon in said second layer prior to extrusion.
Claim 15
Dependent Claim
26 words
A method as claimed in claim 11 in which said bubbles are formed by mixing compressed or condensed freon in said second layer prior to extrusion.
Claim 16
Dependent Claim
26 words
A method as claimed in claim 12 in which said bubbles are formed by mixing compressed or condensed freon in said second layer prior to extrusion.
Claim 17
Dependent Claim
49 words
A method as claimed in claim 1 in which said first layer of plastic film and said second layer are caused to bond together by being coextruded through two channels of a die, which channels merge at a point upstream from the outlet of the orifice of said die.
Claim 18
Dependent Claim
49 words
A method as claimed in claim 2 in which said first layer of plastic film and said second layer are caused to bond together by being coextruded through two channels of a die, which channels merge at a point upstream from the outlet of the orifice of said die.
Claim 19
Dependent Claim
49 words
A method as claimed in claim 3 in which said first layer of plastic film and said second layer are caused to bond together by being coextruded through two channels of a die, which channels merge at a point upstream from the outlet of the orifice of said die.
Claim 20
Dependent Claim
27 words
A method as claimed in claim 1 comprising the additional steps of heating the non-slip plastic film, followed by vacuum forming and trimming to the desired shape.
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) | 1987-12-18 | 1988-06-18 | 1988-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-18 | 1992-06-18 | 1992-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-18 | 1996-06-18 | 1996-12-18 | $7700.00 | Window Closed / Lapsed |