Patent US4810543A successfully refreshed from Google Patents.
US4810543A
Expired / Lapsed
US
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Articles having low friction surfaces and production thereof
Assignee: Tyndale Plains Hunter Ltd
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Filing: 1986-10-17
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Granted: 1989-03-07
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Expires: 2006-10-17
Abstract
Abstract The coefficient of friction of surfaces of articles, wherein the surface comprises a hydrophilic polyurethane polymer, is reduced by treating the surface with a mixture of concentrated sulfuric acid and a low molecular weight organic polyhydroxy compound, and removing excess treating mixture. Typical low friction articles produced thereby are boat hulls having drag resistant coatings, conduits having low friction linings, and cannula or body implants having slippery surfaces.
Inventors
- 👤 Francis E. Gould
- 👤 Charles K. Kliment
- 👤 George E. Seems
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:38
CPC Classifications
F; F16; F16C; F16C33/00; F16C33/02; F16C33/04; F16C33/20; F16C33/201; A; A61; A61L; A61L29/00; A61L29/08; A61L29/085; A61L31/00; A61L31/08; A61L31/10; C; C08; C08J; C08J7/00; C08J7/12; C08J7/14; A61M; A61M25/00; A61M25/0043; A61M2025/0062; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/1352; Y10T428/1386; Y10T428/139; Y10T428/1393; Y10T428/29; Y10T428/2982; Y10T428/2991; Y10T428/31504; Y10T428/31536; Y10T428/31551; Y10T428/31573
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
53 words
As an article of manufacture, a shaped substrate having a low friction surface produced by treating, for an effective period of time, a corresponding precursor surface of a hydrophilic polyurethane polymer on the said substrate with a mixture of concentrated sulfuric acid and a low molecular weight polyhydroxy compound, and removing excess mixture.
Claim 2
Dependent Claim
53 words
As an article of manufacture, a shaped substrate having a low friction surface produced by treating, for an effective period of time, a corresponding precursor surface of a hydrophilic polyurethane polymer on the said substrate with a mixture of concentrated sulfuric acid and a low molecular weight polyhydroxy compound, and removing excess mixture.
Claim 3
Dependent Claim
14 words
The article of manufacture according to claim 1 wherein the substrate is a film.
Claim 4
Dependent Claim
18 words
The article of manufacture according to claim 2 wherein the film is in the form of a glove.
Claim 5
Dependent Claim
21 words
The article of manufacture according to claim 2 wherein the film is in the form of a denture or denture liner.
Claim 6
Dependent Claim
18 words
The article of manufacture according to claim 2 wherein the film is in the form of a condom.
Claim 7
Dependent Claim
15 words
The article of manufacture according to claim 1 wherein the substrate is a contact lens.
Claim 8
Dependent Claim
15 words
The article of manufacture according to claim 1 wherein the substrate is an extruded shape.
Claim 9
Dependent Claim
14 words
The article of manufacture according to claim 1 wherein the substrate is a tube.
Claim 10
Dependent Claim
14 words
The article of manufacture according to claim 1 wherein the substrate is a bead.
Claim 11
Dependent Claim
15 words
The article of manufacture according to claim 1 wherein the substrate is an intravenous catheter.
Claim 12
Dependent Claim
14 words
The article of manufacture according to claim 1 wherein the substrate is a cannulae.
Claim 13
Dependent Claim
15 words
The article of manufacture according to claim 1 wherein the substrate is an intrauterine device.
Claim 14
Dependent Claim
15 words
The article of manufacture according to claim 1 wherein the substrate is a body implant.
Claim 15
Dependent Claim
96 words
An article of manufacture as in claim 1 wherein the hydrophilic polyurethane polymer comprises the reaction product of a mixture of an organic diisocyanate, a low molecular weight alkylene glycol, a polyoxyethylene glycol having a number average molecular weight of from about 400 to about 20,000, and water, the said reaction mixture having an NCO/OH ratio of from about 0.5/1 to about 1.0/1, and wherein the percent by weight in the reaction mixture of the low molecular weight alkylene glycol is no more than about 20% and the water content is no more than about 0.5%.
Claim 16
Dependent Claim
78 words
An article of manufacture as in claim 1 wherein the hydrophilic polyurethane polymer comprises the reaction product of a mixture on a 100% weight basis, of from about 12% to about 55% of methylenebis(cyclohexyl-4,4'-isocyanate), from about 2% to about 20% of a low molecular weight alkylene glycol, from about 25% to about 85% of a polyoxyethylene glycol having a number average molecular weight of from about 1000 to about 8000, and from about 0.1% to about 0.5% water.
Claim 17
Dependent Claim
25 words
The article of manufacture according to claim 1 wherein the hydrophilic polyurethane polymer surface comprises the surface of a hydrophilic polyurethane coating on the substrate.
Claim 18
Dependent Claim
15 words
The article of manufacture according to claim 16 wherein the substrate is a flexible substrate.
Claim 19
Dependent Claim
11 words
The article according to claim 17 wherein the flexible substrate rubber.
Claim 20
Dependent Claim
45 words
The article according to claim 1 wherein the mixture comprises a solution containing on a 100% weight basis from about 10 to about 50 parts of the low molecular weight polyhydroxy compound and from about 50 parts to about 90 parts of concentrated sulfuric acid.
Claim 21
Dependent Claim
39 words
The article according to claim 19 wherein the polyhydroxy compound is selected from ethylene glycol, diethylene glycol, triethylene glycol, glycerol, butanediol, trimethylene glycol, pentaethritol, trimethylol propane and propylene glycol, and the concentration of the sulfuric acid is about 98%.
Claim 22
Dependent Claim
17 words
The article according to claim 1 wherein the treatment period is from about 2 to 30 seconds.
Claim 23
Dependent Claim
49 words
A process for reducing the coefficient of friction of the surface of an article, said surface comprising a hydrophilic polyurethane polymer, said process comprising treating the surface with a mixture of concentrated sulfuric acid and a low molecular weight polyhydroxy compound for an effective time, and removing excess mixture.
Claim 24
Dependent Claim
49 words
A process for reducing the coefficient of friction of the surface of an article, said surface comprising a hydrophilic polyurethane polymer, said process comprising treating the surface with a mixture of concentrated sulfuric acid and a low molecular weight polyhydroxy compound for an effective time, and removing excess mixture.
Claim 25
Dependent Claim
93 words
The process of claim 22 wherein the hydrophilic polyurethane polymer comprises the reaction product of a mixture of an organic diisocyanate, a low molecular weight alkylene glycol, a polyoxyethylene glycol having a number average molecular weight of from about 400 to about 20,000, and water, the said reaction mixture having an NCO/OH ratio of from about 0.5/1 to about 1.0/1, and wherein the percent by weight in the reaction mixture of the low molecular weight alkylene glycol is no more than about 20% and the water content is no more than about 0.5%.
Claim 26
Dependent Claim
76 words
The process of claim 22 wherein the hydrophilic polyurethane polymer comprises the reaction product of a mixture of on a 100% weight basis, of from about 12% to about 55% of methylenebis(cyclohexyl-4,4'-isocyanate), from about 2% to about 20% of a low molecular weight alkylene glycol, from about 25% to about 85% of a polyoxyethylene glycol having a number average molecular weight of from about 1000 to about 8000, and from about 0.1% to about 0.5% water.
Claim 27
Dependent Claim
45 words
The process of claim 22 wherein the treating mixture comprises a solution containing on a 100% weight basis from about 10 to about 50 parts of the low molecular weight polyhydroxy compound and from about 50 parts to about 90 parts of concentrated sulfuric acid.
Claim 28
Dependent Claim
38 words
The process of claim 25 wherein the polyhydroxy compound is selected from ethylene glycol, diethylene glycol, triethylene glycol, glycerol, butanediol, trimethylene glycol, pentaethritol, trimethylol propane and propylene glycol, and the concentration of the sulfuric acid is about 98%.
Claim 29
Dependent Claim
17 words
The process of claim 22 wherein the time of treatment is from about 2 to 30 seconds.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1992-03-06 | 1992-09-05 | 1993-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-03-06 | 1996-09-05 | 1997-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-03-06 | 2000-09-05 | 2001-03-07 | $7700.00 | Window Closed / Lapsed |