US5458935A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermoplastic urethane elastomer
Assignee: Hospira Inc
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Filing: 1993-10-12
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Granted: 1995-10-17
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Expires: 2013-10-12
Abstract
Abstract The invention provides a thermoplastic polyurethane elastomer which contains a blend of polyurethane resins and is suitable for use in the form of tubing. The blend has a tensile strength of more than 7000 psi and an ultimate elongation greater than 200%. The blend contains about 50% to about 80% by weight of an elastomeric polyurethane resin having a hardness in the range of about 60 to 70 Shore D units. The blend additionally contains about 20% to about 50% of a relatively rigid polyurethane resin having a hardness of about 10 units more than the elastomeric resin. The invention also provides methods for using and methods for manufacturing tubing fabricated from the thermoplastic polyurethane elastomer. Preferred extrusion conditions are described.
Inventors
- 👤 Bernard G. Alzner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:02
CPC Classifications
F; F16; F16L; F16L11/00; F16L11/04; F16L11/12; A; A61; A61M; A61M25/00; A61M25/0009; B; B29; B29C; B29C45/00; B29C45/0001; C; C08; C08L; C08L75/00; C08L75/04; F16L11/06; B29C48/00; B29C48/001; B29C48/0019; B29C48/03; B29C48/09; B29K; B29K2075/00; B29K2221/00; B29K2221/003; B29L; B29L2031/00; B29L2031/753; B29L2031/7542; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/1352; Y10T428/1386; Y10T428/1397
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
106 words
Tubing, suitable for use as a catheter which continues to deliver flow when tightly folded, formed of a composition which comprises a blend of resins having a tensile strength of more than about 7000 psi and an ultimate elongation of greater than about 100%, said blend comprising from about 50% to about 80% by weight of an elastomeric polyurethane resin having a hardness in the range of about 60 to about 70 Shore D units and from about 20% to 50% by weight of a relatively rigid polyurethane resin having a hardness of about 10 Shore D units greater than the hardness of the elastomeric resin.
Claim 2
Dependent Claim
106 words
Tubing, suitable for use as a catheter which continues to deliver flow when tightly folded, formed of a composition which comprises a blend of resins having a tensile strength of more than about 7000 psi and an ultimate elongation of greater than about 100%, said blend comprising from about 50% to about 80% by weight of an elastomeric polyurethane resin having a hardness in the range of about 60 to about 70 Shore D units and from about 20% to 50% by weight of a relatively rigid polyurethane resin having a hardness of about 10 Shore D units greater than the hardness of the elastomeric resin.
Claim 3
Dependent Claim
35 words
The tubing of claim 1, further characterized in that the elastomeric resin has an ultimate elongation of more than about 100% and the relatively rigid resin has an ultimate elongation of less than about 50%.
Claim 4
Dependent Claim
17 words
The tubing of claim 1, further characterized in that the blend of resins is a thermoplastic elastomer.
Claim 5
Dependent Claim
47 words
The tubing of claim 1, further characterized in that the tubing has a passage for flow within and exhibits a residual angle of about 45 degrees or less after being folded in a tight 180 degree bend, pinched until the passage for flow is blocked, and released.
Claim 6
Dependent Claim
41 words
The tubing of claim 4, further characterized in that the tubing, when folded into a tight 90 degree bend, is capable of passing about 85% or more of the flow that could be passed by a straight tube of equal dimensions.
Claim 7
Independent Claim
120 words
A method of manufacturing tubing suitable for use as a catheter, which comprises: mixing from about 50% to about 80% by weight of an elastomeric polyurethane resin having a hardness in the range of about 60 to about 70 Shore D units with from about 20% to about 50% by weight of a relatively rigid polyurethane resin having a hardness of about 10 Shore D units greater than the hardness of the elastomeric resin to produce a mixture of resins; fusing the mixture of resins to produce a blend of resins having a tensile strength of more than about 7000 psi and an ultimate elongation of greater than about 200%; and extruding the blend of resins to produce the tubing.
Claim 8
Independent Claim
120 words
A method of manufacturing tubing suitable for use as a catheter, which comprises: mixing from about 50% to about 80% by weight of an elastomeric polyurethane resin having a hardness in the range of about 60 to about 70 Shore D units with from about 20% to about 50% by weight of a relatively rigid polyurethane resin having a hardness of about 10 Shore D units greater than the hardness of the elastomeric resin to produce a mixture of resins; fusing the mixture of resins to produce a blend of resins having a tensile strength of more than about 7000 psi and an ultimate elongation of greater than about 200%; and extruding the blend of resins to produce the tubing.
Claim 9
Dependent Claim
35 words
The method of claim 6, further characterized in that the elastomeric resin has an ultimate elongation of more than about 100% and the relatively rigid resin has an ultimate elongation of less than about 50%.
Claim 10
Dependent Claim
46 words
The method of claim 6, further characterized in that the blend of resins is extruded from a die having an average diameter which is in the range of about 2.0 to about 10.0 times as large as the average diameter of the tubing after said extruding.
Claim 11
Dependent Claim
43 words
The method of claim 8, further characterized in that the blend of resins is extruded from a die having an average diameter which is in the range of about 4.0 to about 5.0 times the average diameter of the tubing after said extruding.
Claim 12
Dependent Claim
43 words
The method of claim 6, further characterized in that the blend of resins is extruded from a die having a wall gap which is in the range of about 2.0 to about 10.0 times the wall thickness of the tubing after said extruding.
Claim 13
Dependent Claim
36 words
The method of claim 6, further characterized in that the blend of resin is extruded from a die having a diameter draw ratio of 4.0 to 10.0 and a wall draw ratio of 4.0 to 10.0.
Claim 14
Dependent Claim
27 words
The method of claim 6, further characterized in that the blend of resins is extruded from a die having an area draw ratio of 18.0 or more.
Claim 15
Dependent Claim
22 words
The method of claim 6, further characterized by cooling the blend of resins after said fusing to produce a solid intermediate product.
Claim 16
Independent Claim
119 words
A method of manufacturing short tube sections, which comprises: mixing from about 50% to about 80% by weight of an elastomeric polyurethane resin having a hardness in the range of about 60 to about 70 Shore D units with from about 20% to about 50% by weight of a relatively rigid polyurethane resin having a hardness of about 10 Shore D units greater than the hardness of the elastomer resin to produce a mixture of resins; fusing the mixture of resins to produce a blend of resins having a tensile strength of more than about 7000 psi and an ultimate elongation of greater than about 200%; and injection molding the blend of resins to produce a short tube section.
Claim 17
Independent Claim
119 words
A method of manufacturing short tube sections, which comprises: mixing from about 50% to about 80% by weight of an elastomeric polyurethane resin having a hardness in the range of about 60 to about 70 Shore D units with from about 20% to about 50% by weight of a relatively rigid polyurethane resin having a hardness of about 10 Shore D units greater than the hardness of the elastomer resin to produce a mixture of resins; fusing the mixture of resins to produce a blend of resins having a tensile strength of more than about 7000 psi and an ultimate elongation of greater than about 200%; and injection molding the blend of resins to produce a short tube section.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-10-16 | 1999-04-17 | 1999-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-10-16 | 2003-04-17 | 2003-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-10-16 | 2007-04-17 | 2007-10-17 | $7700.00 | Window Closed / Lapsed |