Patent US3940535A successfully refreshed from Google Patents.
US3940535A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reversible moisture-vapor-absorptive sheet structures and process
Assignee: BASF SE
•
Filing: 1973-11-21
•
Granted: 1976-02-24
•
Expires: 1993-11-21
Abstract
Abstract Reversibly moisture-vapor-absorptive sheet materials and a process for their manufacture in which water-soluble polymers of vinyl ethers are combined with base materials and crosslinked thereon.
Inventors
- 👤 Rudolf Gaeth
- 👤 Roland Linke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 02:03
CPC Classifications
D; D04; D04H; D04H1/00; D04H1/40; D04H1/58; D04H1/64; D04H1/645; D04H1/42; D04H1/4326; D04H1/4334; D04H1/435; D04H1/587; D04H1/65; D04H5/00; D04H5/04; D06; D06N; D06N3/00; D06N3/04; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2933; Y10T428/294; Y10T428/296; Y10T428/31504; Y10T428/31855; Y10T442/00; Y10T442/20; Y10T442/2033; Y10T442/2484
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
114 words
A process for the manufacture of reversibly moisture-vapor-absorptive sheet material which comprises: a. applying an aqueous solution of a water-soluble vinyl ether polymer to a base material which is gas permeable; whereby said base material is impregnated with said aqueous solution; b. heating said impregnated base material sufficiently to cause said water soluble vinyl ether polymer to precipitate from said solution whereby said polymer is fixed in said base material; c. cross-linking said vinyl ether polymer; and d. drying said sheet material, the amount of water soluble vinyl ether polymer applied to said base in a) being sufficient to produce a final sheet material containing from 10 to 70% by weight of said polymer.
Claim 2
Dependent Claim
114 words
A process for the manufacture of reversibly moisture-vapor-absorptive sheet material which comprises: a. applying an aqueous solution of a water-soluble vinyl ether polymer to a base material which is gas permeable; whereby said base material is impregnated with said aqueous solution; b. heating said impregnated base material sufficiently to cause said water soluble vinyl ether polymer to precipitate from said solution whereby said polymer is fixed in said base material; c. cross-linking said vinyl ether polymer; and d. drying said sheet material, the amount of water soluble vinyl ether polymer applied to said base in a) being sufficient to produce a final sheet material containing from 10 to 70% by weight of said polymer.
Claim 3
Dependent Claim
26 words
A process as set forth in claim 1 wherein said gas permeable base material has a web structure and is formed from organic or inorganic fibers.
Claim 4
Dependent Claim
26 words
A process as set forth in claim 1 wherein cross-linking of said vinyl ether polymer is affected by applying high energy radiation to said base material.
Claim 5
Dependent Claim
25 words
A process as set forth in claim 1 wherein the final web structure contains from 20 to 60% by weight of said vinyl ether polymer.
Claim 6
Dependent Claim
20 words
A process as set forth in claim 1 wherein said flocculation and cross-linking steps are carried out in hot water.
Claim 7
Dependent Claim
10 words
Moisture-vapor-absorptive sheet material prepared by the process of claim 1.
Claim 8
Dependent Claim
33 words
A process as set forth in claim 1 wherein said aqueous solution of ether polymer contains a cross-linking catalyst and whereby said precipitation step and said cross-linking step occur at the same time.
Claim 9
Dependent Claim
15 words
A process as set forth in claim 7 wherein said cross-linking catalyst is a peroxide.
Claim 10
Dependent Claim
44 words
A process as set forth in claim 7 wherein said base material impregnated with an aqueous solution of vinyl ether polymer containing a cross-linking catalyst is heated to a temperature of at least 5° C above the cloud point of the vinyl ether solution.
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) | 1979-02-23 | 1979-08-25 | 1980-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-02-23 | 1983-08-25 | 1984-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-02-23 | 1987-08-25 | 1988-02-24 | $7700.00 | Window Closed / Lapsed |