US4755420A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dryer fabric having warp strands made of melt-extrudable polyphenylene sulphide
Assignee: Jwi Ltd
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Filing: 1986-01-24
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Granted: 1988-07-05
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Expires: 2006-01-24
Abstract
Abstract A dryer fabric for use in a dryer section of a paper machine wherein at least a portion of the machine direction components are monofilaments made from polyphenylene sulphide or a blend of polyphenylene sulphide and heat-stabilized polyamide 66. When using a blend the polyamide 66 is present in the range of up to about 20% by weight.
Inventors
- 👤 Samuel M. Baker
- 👤 F. Brian Best
- 👤 Girish M. Bhatt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:55
CPC Classifications
D; D21; D21F; D21F1/00; D21F1/0027; D21F1/0072; D21F1/0036; Y; Y10; Y10T; Y10T428/00; Y10T428/249921; Y10T428/249922; Y10T428/31504; Y10T428/31533
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
139 words
A dryer fabric for use in a dryer section of a paper machine, comprising a woven fabric or a fabric of a plurality of helical coils connected together by hinge pins, wherein at least a portion of the machine direction components of the fabric are made from monofilaments composed of a blend of polyphenylene sulfide and from an effective amount to up to about 20% by weight of an additive which imparts toughness to the monofilament without substantially reducing the hydrolysis resistance inherent in polyphenylene sulfide, said additive having a higher melt viscosity than the polyphenylene sulfide at extrusion temperatures, resistance to thermal degradation at extrusion temperatures, and chemical compatibility with said polyphenylene sulfide, and wherein said additive is present in small discrete elongated globules with the long axis of said globules parallel to the axis of the monofilament.
Claim 2
Dependent Claim
139 words
A dryer fabric for use in a dryer section of a paper machine, comprising a woven fabric or a fabric of a plurality of helical coils connected together by hinge pins, wherein at least a portion of the machine direction components of the fabric are made from monofilaments composed of a blend of polyphenylene sulfide and from an effective amount to up to about 20% by weight of an additive which imparts toughness to the monofilament without substantially reducing the hydrolysis resistance inherent in polyphenylene sulfide, said additive having a higher melt viscosity than the polyphenylene sulfide at extrusion temperatures, resistance to thermal degradation at extrusion temperatures, and chemical compatibility with said polyphenylene sulfide, and wherein said additive is present in small discrete elongated globules with the long axis of said globules parallel to the axis of the monofilament.
Claim 3
Dependent Claim
16 words
The dryer fabric as claimed in claim 1, wherein said additive is a heat-stabilized polyamide 66.
Claim 4
Dependent Claim
23 words
The dryer fabric as claimed in claim 2 wherein said polyphenylene sulphide is blended with about 6% by weight of heat-stabilized polyamide 66.
Claim 5
Dependent Claim
21 words
The dryer fabric as claimed in claim 2 wherein said machine direction components are warp strands in a woven dryer fabric.
Claim 6
Dependent Claim
35 words
The dryer fabric as claimed in claim 4 wherein said warp strands are flattened warp strands having an essentially rectangular cross-section with the long axis of the rectangle lying in the plane of said fabric.
Claim 7
Dependent Claim
30 words
The dryer fabric as claimed in claim 5 wherein said woven dryer fabric has flattened warp strands having an essentially rectangular cross-section with a flatness ratio between 1.5:1 and 2.5:1.
Claim 8
Dependent Claim
24 words
The dryer fabric as claimed in claim 2 wherein said machine direction components comprise a plurality of helical coils connected together by hinge pins.
Claim 9
Dependent Claim
40 words
The dryer fabric as claimed in claim 7 wherein the monofilament of said helical coils has an essentially rectangular cross-section when viewed in the machine direction with the long axis of the rectangle lying in the plane of said fabric.
Claim 10
Dependent Claim
20 words
The dryer fabric as claimed in claim 8 wherein said rectangular cross-section has a flatness ratio between 1.1:1 and 2.5:1.
Claim 11
Dependent Claim
61 words
The dryer fabric as claimed in claim 1, which comprises a plurality of interwoven warp and weft strands, wherein at least a portion of the warps are monofilaments made of a blend of polyphenylene sulfide with heat-stabilized polyamide 66, said warp strands having an essentially rectangular cross-section with the long axis of the rectangle lying in the plane of the fabric.
Claim 12
Dependent Claim
18 words
The dryer fabric as claimed in claim 1, wherein said monofilaments have a size of about 0.0040-0.0600 inches.
Claim 13
Dependent Claim
18 words
The dryer fabric as claimed in claim 11, wherein said monofilaments have a size of about 0.0078-0.0400 inches.
Claim 14
Dependent Claim
23 words
The dryer fabric as claimed in claim 1, wherein said fabric has a warp count in the range of 25-80 strands per inch.
Claim 15
Dependent Claim
26 words
The dryer fabric as claimed in claim 1, wherein said fabric has flattened warp strands having a major axis measurement in the range of 0.0125-0.050 inches.
Claim 16
Dependent Claim
90 words
A synthetic industrial fabric having excellent toughness and low breakage, said fabric comprising a woven fabric or a fabric of a plurality of helical coils connected together by hinge pins, wherein at least a portion of the machine direction components of the fabric are made from monofilaments composed of a blend of polyphenylene sulfide and heat-stabilized polyamide 66, said heat-stabilized polyamide 66 being present in an effective amount to of up to about 20% by weight, said heat-stabilized polyamide 66 being present to effect said enhanced toughness and low breakage.
Claim 17
Dependent Claim
90 words
A synthetic industrial fabric having excellent toughness and low breakage, said fabric comprising a woven fabric or a fabric of a plurality of helical coils connected together by hinge pins, wherein at least a portion of the machine direction components of the fabric are made from monofilaments composed of a blend of polyphenylene sulfide and heat-stabilized polyamide 66, said heat-stabilized polyamide 66 being present in an effective amount to of up to about 20% by weight, said heat-stabilized polyamide 66 being present to effect said enhanced toughness and low breakage.
References Cited (Backward Citations)
US3919177A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-07-05 | 1992-01-04 | 1992-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-07-05 | 1996-01-04 | 1996-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-07-05 | 2000-01-04 | 2000-07-05 | $7700.00 | Window Closed / Lapsed |