US5229184A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat shrinkable fibres and products therefrom
Assignee: Albany International Corp
•
Filing: 1989-02-24
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Granted: 1993-07-20
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Expires: 2009-02-24
Abstract
Abstract This invention relates to a composition of matter having a fibre structure incorporating a major proportion of heat shrinkable fibres, the structure includes within it discreet fibre groupings which serve to provide structural elements within the composition. The composition of the invention is capable of being formed to provide shaped products. A particular aspect of the invention relates to compositions comprising flame retardant fibres typically polyimide fibres which enables the production of flame retardent compositions. The density of the structures can be controlled as can the rigidity thereof.
Inventors
- 👤 Frederick S. Campbell
- 👤 Gordon J. Varney
- 👤 Dewitt R. Petterson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 14:17
CPC Classifications
D; D04; D04H; D04H1/00; D04H1/04; D04H1/06; D04H1/40; D04H1/44; D04H1/46; D04H1/48; D04H1/482; D04H1/485; D04H1/492; D04H1/54; Y; Y10; Y10S; Y10S264/00; Y10S264/71; Y10S428/00; Y10S428/913; Y10T; Y10T428/00; Y10T428/24; Y10T428/24058; Y10T428/24124; Y10T428/24174; Y10T428/24182; Y10T428/24628; Y10T428/31504; Y10T428/31721
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
72 words
A fibre structure formed from a layer comprising a major proportion of heat shrinkable organic fiber, characterized in that said structure includes discrete fiber groups which extend in the thickness direction transverse the longitudinal plane of the layer, and in that said structure on heat treatment produces a structure of increased density in which the density of said discrete fiber groups is greater than the density of the remainder of the structure.
Claim 2
Dependent Claim
72 words
A fibre structure formed from a layer comprising a major proportion of heat shrinkable organic fiber, characterized in that said structure includes discrete fiber groups which extend in the thickness direction transverse the longitudinal plane of the layer, and in that said structure on heat treatment produces a structure of increased density in which the density of said discrete fiber groups is greater than the density of the remainder of the structure.
Claim 3
Dependent Claim
114 words
A fibre structure as claimed in claim 1 in the form of a shaped article, said shaped article being produced by a method which comprises forming a fibre structure comprising a heat shrinkable fibre, said structure having said discrete fibre groups, locating said structure contiguous to a shaping surface, constraining said structure against shrinkage in at least one direction, and, either prior to or simultaneous with said locating step, subjecting said material to heat at a temperature and for a time sufficient to obtain a structure of increased density in which the density of the fibre groups is greater than the remainder of the structure, and thereafter removing said shaped article from said surface.
Claim 4
Dependent Claim
34 words
A fibre structure as claimed in claim 2, characterized in that said material has been subjected to heat at a temperature and for a time sufficient to shrink the fibre to obtain fibre-to-fibre bonding.
Claim 5
Dependent Claim
41 words
A fibre structure as claimed in claim 1, characterized in that said discrete fibre groups have been densified and rigidified to form a structural component within the structure per se to impart a degree of structural rigidity to the resultant structure.
Claim 6
Dependent Claim
63 words
A fibre structure as claimed in claim 4, characterized in that the structure has been subjected to a treatment comprising heating to a temperature sufficient to allow densification to occur while constrained against shrinkage in at least one direction, locating said structure contiguous to a shaping surface while maintaining said constraint, continuing to constrain said structure during cooling and thereafter removing said constraint.
Claim 7
Dependent Claim
33 words
A fibre structure as claimed in claim 5, characterized in that the fibre structure has been constrained in at least two dimensions against shrinkage thereby allowing shrinkage substantially only in the third dimension.
Claim 8
Dependent Claim
29 words
A fibre structure as claimed in claim 5, characterized in that the shaping surface comprises at least two cooperating surfaces which cooperate to produce a three dimensional contoured panel.
Claim 9
Dependent Claim
36 words
A fibre structure as claimed in claim 1, characterized in that said structure has a plurality of elongate elements therein, each element comprising a group of fibres oriented in a plane and densified by heat treatment.
Claim 10
Dependent Claim
27 words
A fibre structure as claimed in claim 1, characterized in that said structure is selected from the group consisting of non-woven felts, knitted materials and woven materials.
Claim 11
Dependent Claim
23 words
A fibre structure as claimed in claim 9, characterized in that said structure is a batt comprising a series of separate fibre layers.
Claim 12
Dependent Claim
23 words
A fibre structure, characterized in that said structure is formed by several layers of fibre material as defined in claim 1 laminated together.
Claim 13
Dependent Claim
40 words
A fibre structure as claimed in claim 11, characterized in that said layers are laminated together by adhesives, said adhesives being selected from the group consisting of acrylic adhesives, polyester adhesives, polyamide adhesives, polyolefin adhesives, polyurethane adhesives and polyimide adhesives.
Claim 14
Dependent Claim
21 words
A fibre structure as claimed in claim 1, characterized in that said fibre groups are formed by needling or by hydroentangling.
Claim 15
Dependent Claim
22 words
A fibre structure as claimed in claim 1, characterized in that the density is within the range of 0.005 to 1.2 gm/cc.
Claim 16
Dependent Claim
28 words
A fibre structure as claimed in claim 1, said fibre structure being a felt layer in which fibre lengths are oriented within the plane of the felt layer.
Claim 17
Dependent Claim
47 words
A fibre structure as claimed in claim 15, said fibre structure comprising multiple felt layers and characterized in that oriented fibres are disposed in discrete laminae within each layer, said laminae being arranged such that the orientation directions of adjacent laminae define an angle greater than 5°.
Claim 18
Dependent Claim
51 words
A fibre structure as claimed in claim 1, characterised in that the fibres constituting said major proportion of the fibres of said structure are heat shrinkable fibres selected from the group consisting of polyamide fibres, acrylic fibres, polypropylene fibres, polyphenylene sulphide fibres, polyimide fibres, aromatic ether ketone fibres and polyetherimide fibres.
Claim 19
Dependent Claim
32 words
A fibre structure as claimed in claim 1, characterized in that the individual fibres thereof include a proportion of not more than 5% by weight of a plasticizing low molecular weight material.
Claim 20
Dependent Claim
39 words
A fibre structure as claimed in claim 1, characterized in that said low molecular weight plasticizing material is selected from the group consisting of solvents for the fibre polymer and low molecular weight oligomers of the same polymer material.
Claim 21
Dependent Claim
38 words
A fibre structure as claimed in claim 18, characterized in that the fibres are polyimide fibres and the plasticising material is a solvent selected from the group consisting of dimethyl formamide, N-methyl pyrrolidone, N-vinyl pyrrolidone and dimethyl acetamide.
Claim 22
Dependent Claim
73 words
A fibre structure as claimed in claim 1, said structure being a laminated assembly formed from several layers of rigidified non-woven material, said structure having groups of fibres extending in thickness the direction transverse the longitudinal plane of each layer, and said structure being shaped to allow said groups of densified fibres to form a structural component within each layer per se to impart a degree of structural rigidity to the resultant laminate.
Claim 23
Dependent Claim
31 words
A fibre structure as claimed in claim 1, characterized in that the fibres of said structure have been subjected to a draw ratio during forming of between 2 and 7 times.
Claim 24
Dependent Claim
41 words
A fibre structure as claimed in claim 1, characterized in that the fibres are capable of an inherent shrinkage of at least 15 to 80% on heating in order to provide the appropriate shrinkage and densification of the cohesive fibre assembly.
Claim 25
Dependent Claim
44 words
A fibre structure as claimed in claim 1, said fibre structure comprising a major proportion of polyimide fibres based on units of the general formula ##STR6## wherein n is an integer greater than 1 and R is the group ##STR7## and/or the group ##STR8##
Claim 26
Dependent Claim
78 words
A method of producing a fibre structure in the form of a shaped article, said method comprising forming a fibre structure comprising heat shrinkable fibres as claimed in claim 1, heating said structure to a temperature sufficient to allow densification to occur while constraining said structure against shrinkage in at least one direction, locating said densified structure contiguous to a shaping surface while maintaining said constraint, cooling said structure while maintaining said constraint, and thereafter removing said constraint.
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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) | 1996-07-19 | 1997-01-18 | 1997-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-07-19 | 2001-01-18 | 2001-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-07-19 | 2005-01-18 | 2005-07-20 | $7700.00 | Window Closed / Lapsed |