US5478620A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multilayer plastic pipe
Assignee: Huels AG
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Filing: 1994-02-28
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Granted: 1995-12-26
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Expires: 2014-02-28
Abstract
Abstract Multilayer plastic pipes comprising a polyamide-based inner and outer layer, wherein the inner and outer layer are connected force-lockingly by means of at least one intermediate layer made of a mixture of a linear crystalline polyester and a polyamide, have improved stability to chemical agents and improved mechanical properties.
Inventors
- 👤 Joachim Mugge
- 👤 Hubertus Ohm
- 👤 Hans-Dieter Herrmann
- 👤 Hans Ries
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 04:24
CPC Classifications
F; F16; F16L; F16L9/00; F16L9/12; F16L9/133; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/1352; Y10T428/139; Y10T428/1393
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
61 words
A multilayer plastic pipe, comprising polyamide inner and outer layers, wherein said inner and outer layers are connected by means of at least one intermediate layer comprising (i) a mixture of a linear crystalline polyester and a polyamide or (ii) a polyester/polyamide copolymer, wherein said polyester and polyamide are present in a weight ratio ranging from 30 to 70:70 to 30.
Claim 2
Dependent Claim
61 words
A multilayer plastic pipe, comprising polyamide inner and outer layers, wherein said inner and outer layers are connected by means of at least one intermediate layer comprising (i) a mixture of a linear crystalline polyester and a polyamide or (ii) a polyester/polyamide copolymer, wherein said polyester and polyamide are present in a weight ratio ranging from 30 to 70:70 to 30.
Claim 3
Dependent Claim
21 words
The multilayer plastic pipe of claim 1, wherein said intermediate layer is a mixture of a crystalline polyester and a polyamide.
Claim 4
Dependent Claim
15 words
The multilayer plastic pipe of claim 1, wherein said intermediate layer is a polyester/polyamide copolymer.
Claim 5
Dependent Claim
29 words
The multilayer plastic pipe of claim 1, wherein said polyester and polyamide in said intermediate layer are present in a weight ratio ranging from 40 to 60:60 to 40.
Claim 6
Dependent Claim
33 words
The multilayer plastic pipe of claim 1, wherein said polyester in said intermediate layer is obtained by (poly)condensing an aliphatic diol, an alicyclic diol, or a mixture thereof with an aromatic dicarboxylic acid.
Claim 7
Dependent Claim
33 words
The multilayer plastic pipe of claim 1, wherein said intermediate layer comprises at least one polyamide selected from the group consisting of 4,6-; 6-; 6,6-; 6,12-; 8,10-; 10,10-; 10,12-; 11-; 12-; and 12,12-polyamide.
Claim 8
Dependent Claim
12 words
The multilayer plastic pipe of claim 1, which is a fuel pipe.
Claim 9
Dependent Claim
13 words
The multilayer plastic pipe of claim 1, which is an automobile fuel line.
Claim 10
Dependent Claim
60 words
A multilayer plastic pipe having polyamide inner and outer layers, wherein said inner and outer layers are connected by means of an intermediate layer consisting of (i) a mixture of a linear crystalline polyester and a polyamide or (ii) a polyester/polyamide copolymer, wherein said polyester and polyamide are present in a weight ratio ranging from 30 to 70:70 to 30.
Claim 11
Dependent Claim
60 words
A multilayer plastic pipe having polyamide inner and outer layers, wherein said inner and outer layers are connected by means of an intermediate layer consisting of (i) a mixture of a linear crystalline polyester and a polyamide or (ii) a polyester/polyamide copolymer, wherein said polyester and polyamide are present in a weight ratio ranging from 30 to 70:70 to 30.
References Cited (Backward Citations)
US3233024A
Cited
US3584656A
Cited
US4443519A
Cited
US5038833A
Cited
US4725488A
Cited
US4800109A
Cited
US5084352A
Cited
US5258213A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-12-25 | 1999-06-26 | 1999-12-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-12-25 | 2003-06-26 | 2003-12-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-12-25 | 2007-06-26 | 2007-12-26 | $7700.00 | Window Closed / Lapsed |