US4639390A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of non-woven fabric containing polyvinyl alcohol fiber
Assignee: Carl Freudenberg KG
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Filing: 1985-11-01
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Granted: 1987-01-27
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Expires: 2005-11-01
Abstract
Abstract The present invention is in a web and method for preparation of non-woven fabric which contains polyvinyl alcohol fiber comprising the steps of forming a web containing scarcely soluble polyvinyl alcohol fiber which is soluble or swellable in the presence of water at a temperature of 90° C. or higher in the amount at least 10% by weight, providing water in said web, and partially thermally bonding the web so that bonded area occupies 5 to 40% of the web area.
Inventors
- 👤 Rikuo Shoji
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:16
CPC Classifications
D; D04; D04H; D04H1/00; D04H1/40; D04H1/54; Y; Y10; Y10S; Y10S428/00; Y10S428/913; Y10T; Y10T428/00; Y10T428/24; Y10T428/24479; Y10T428/24595; Y10T428/24603; Y10T428/24802; Y10T442/00; Y10T442/60; Y10T442/69; Y10T442/692
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
84 words
A method for preparation of non-woven fabric which contains polyvinyl alcohol fibers comprising: forming a web containing slightly soluble polyvinyl alcohol fiber which is soluble or swellable in the presence of water at a temperature of 90° C. or higher in the amount of at least 10% by weight; providing water in said web to obtain a water content of at least 20% by weight; and partially thermally bonding the web so that the bonded area occupies 5 to 40% of the web area.
Claim 2
Independent Claim
84 words
A method for preparation of non-woven fabric which contains polyvinyl alcohol fibers comprising: forming a web containing slightly soluble polyvinyl alcohol fiber which is soluble or swellable in the presence of water at a temperature of 90° C. or higher in the amount of at least 10% by weight; providing water in said web to obtain a water content of at least 20% by weight; and partially thermally bonding the web so that the bonded area occupies 5 to 40% of the web area.
Claim 3
Dependent Claim
15 words
The method of claim 1 wherein the web is additionally formed of a synthetic fiber.
Claim 4
Dependent Claim
24 words
The method of claim 2 wherein the synthetic fiber is selected from the group consisting of polyester, polyamide, polyacrylonitrile fiber, and cellulosic regenerated fiber.
Claim 5
Dependent Claim
11 words
The method of claim 2 wherein the synthetic fiber is rayon.
Claim 6
Dependent Claim
16 words
The method of claim 1 wherein the PVA fiber is heat-treated and suitably combined by acetalization.
Claim 7
Dependent Claim
27 words
The method of claim 1 wherein the water provided to said web is such that the water content of the web does not exceed 300% by weight.
Claim 8
Dependent Claim
19 words
The method of claim 1 wherein the water content of the web is from 60 to 200% by weight.
Claim 9
Dependent Claim
52 words
A partially thermally bonded web comprising slightly soluble polyvinyl alcohol fiber which is soluble or swellable in the presence of water at a temperature of 90° C. or higher in the amount at least 10% by weight wherein the bonded area of the web occupies 5 to 40% of the web area.
Claim 10
Dependent Claim
52 words
A partially thermally bonded web comprising slightly soluble polyvinyl alcohol fiber which is soluble or swellable in the presence of water at a temperature of 90° C. or higher in the amount at least 10% by weight wherein the bonded area of the web occupies 5 to 40% of the web area.
Claim 11
Dependent Claim
10 words
The web of claim 8 further comprising a synthetic fiber.
Claim 12
Dependent Claim
11 words
The web of claim 8 wherein the synthetic fiber is polyester.
Claim 13
Dependent Claim
11 words
The web of claim 9 wherein the synthetic material is rayon.
Claim 14
Dependent Claim
16 words
The web of claim 9 wherein the PVA fiber is heat-treated and suitably combined by acetalization.
Claim 15
Dependent Claim
18 words
The web of claim 9 wherein the water content of the web is at least 20% by weight.
Claim 16
Dependent Claim
7 words
The web of claim 8 including additives.
Claim 17
Dependent Claim
11 words
The web of claim 8 wherein the synthetic fiber is polyamide.
Claim 18
Dependent Claim
12 words
The web of claim 8 wherein the synthetic fiber is polyacrylonitrile fiber.
Claim 19
Dependent Claim
13 words
The web of claim 8 wherein the synthetic fiber is cellulosic regenerated fiber.
Claim 20
Dependent Claim
28 words
The web of claim 9 wherein the synthetic fiber is a blend of fibers selected from the group consisting of polyester, polyamide, polyacrylonitril fiber and cellulosic regenerated fiber.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-01-26 | 1990-07-28 | 1991-01-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-26 | 1994-07-28 | 1995-01-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-26 | 1998-07-28 | 1999-01-27 | $7700.00 | Window Closed / Lapsed |