Patent US4086193A successfully refreshed from Google Patents.
US4086193A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microporous sheets and a process for making them
Assignee: Bayer AG
•
Filing: 1974-08-29
•
Granted: 1978-04-25
•
Expires: 1994-08-29
Abstract
Abstract A method for making microporous sheets is provided wherein a dispersion of a cationic and/or anionic polyurethane is mixed with a solution containing a non-ionic polyurethane and the resulting mixture is coagulated with a non-solvent for the non-ionic polyurethane.
Inventors
- 👤 Artur Reischl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 11:21
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/28; C08L; C08L75/00; D; D06; D06M; D06M15/00; D06M15/19; D06M15/37; D06M15/564; D06M15/643; D06M15/6436; D06M15/653; D06N; D06N3/00; D06N3/12; D06N3/14; C08J2375/00
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
38 words
A microporous sheet prepared by coagulation of a solution containing a non-ionic polyurethane in a polar solvent therefor mixed with an aqueous dispersion of a cationic polyurethane and an anionic polyurethane with a non-solvent for said non-ionic polyurethane.
Claim 2
Dependent Claim
38 words
A microporous sheet prepared by coagulation of a solution containing a non-ionic polyurethane in a polar solvent therefor mixed with an aqueous dispersion of a cationic polyurethane and an anionic polyurethane with a non-solvent for said non-ionic polyurethane.
Claim 3
Dependent Claim
60 words
A microporous sheet prepared by coagulation of a solution containing a non-ionic polyurethane in a polar solvent therefor mixed with an aqueous dispersion of either a cationic polyurethane or an anionic polyurethane with a non-solvent for the polyurethane, said aqueous dispersion being sedimenting and redispersible, having a particle size of 0.8 to 100 microns, and being insoluble in boiling dimethylformamide.
Claim 4
Dependent Claim
60 words
A microporous sheet prepared by coagulation of a solution containing a non-ionic polyurethane in a polar solvent therefor mixed with an aqueous dispersion of either a cationic polyurethane or an anionic polyurethane with a non-solvent for the polyurethane, said aqueous dispersion being sedimenting and redispersible, having a particle size of 0.8 to 100 microns, and being insoluble in boiling dimethylformamide.
Claim 5
Dependent Claim
51 words
In a process for making microporous sheets which are permeable to water vapor comprising coagulating a hygroscopic polyurethane solution, the improvement which comprises mixing a suspension of a cationic polyurethane and an anionic polyurethane with a solution containing a non-ionic polyurethane in a polar solvent therefor before coagulation of the solution.
Claim 6
Dependent Claim
51 words
In a process for making microporous sheets which are permeable to water vapor comprising coagulating a hygroscopic polyurethane solution, the improvement which comprises mixing a suspension of a cationic polyurethane and an anionic polyurethane with a solution containing a non-ionic polyurethane in a polar solvent therefor before coagulation of the solution.
Claim 7
Dependent Claim
16 words
The process of claim 3, wherein said suspension contains a non-ionic or an ionic polyurethane polysiloxane.
Claim 8
Dependent Claim
21 words
The process of claim 3, wherein the polyurethane solute in the solution is a non-ionic polyurethane substantially free from urea linkages.
Claim 9
Dependent Claim
16 words
The process of claim 3, wherein at least one of the polyurethanes is a polyurethane urea.
Claim 10
Dependent Claim
8 words
The product of the process of claim 3.
Claim 11
Independent Claim
48 words
A method for making a microporous sheet which comprises coating a substrate with a hygroscopic solution containing a non-ionic polyurethane dissolved in a polar solvent therefor mixed with an aqueous dispersion or colloidal solution of a cationic polyurethane and an anionic polyurethane, and exposing the coating to moisture.
Claim 12
Independent Claim
48 words
A method for making a microporous sheet which comprises coating a substrate with a hygroscopic solution containing a non-ionic polyurethane dissolved in a polar solvent therefor mixed with an aqueous dispersion or colloidal solution of a cationic polyurethane and an anionic polyurethane, and exposing the coating to moisture.
Claim 13
Dependent Claim
77 words
In a process for making microporous sheets which are permeable to water vapor comprising coagulating a hygroscopic polyurethane solution the improvement which comprises mixing a suspension of either a cationic polyurethane or an anionic polyurethane with a solution containing a polyurethane in a polar solvent therefor before coagulation of the solution, wherein said cationic or anionic polyurethane suspension is sedimenting and redispersible, has a particle size of 0.8 to 100 microns, and is insoluble in boiling dimethylformamide.
Claim 14
Dependent Claim
77 words
In a process for making microporous sheets which are permeable to water vapor comprising coagulating a hygroscopic polyurethane solution the improvement which comprises mixing a suspension of either a cationic polyurethane or an anionic polyurethane with a solution containing a polyurethane in a polar solvent therefor before coagulation of the solution, wherein said cationic or anionic polyurethane suspension is sedimenting and redispersible, has a particle size of 0.8 to 100 microns, and is insoluble in boiling dimethylformamide.
Claim 15
Dependent Claim
16 words
The process of claim 9, wherein said suspension contains a non-ionic or an ionic polyurethane polysiloxane.
Claim 16
Dependent Claim
21 words
The process of claim 9, wherein the polyurethane solute in the solution is a non-ionic polyurethane substantially free from urea linkages.
Claim 17
Dependent Claim
16 words
The process of claim 9, wherein at least one of the polyurethanes is a polyurethane urea.
Claim 18
Dependent Claim
8 words
The product of the process of claim 9.
Claim 19
Independent Claim
78 words
A method for making a microporous sheet which comprises coating a substrate with a hygroscopic solution containing a non-ionic polyurethane dissolved in a polar solvent therefor mixed with an aqueous dispersion or colloidal solution of either a cationic polyurethane or an anionic polyurethane and exposing the coating to moisture, said aqueous dispersion or said collodial solution being characterized as being sedimenting and redispersible, having a particle size of 0.8 to 100 microns, and being insoluble in boiling dimethylformamide.
Claim 20
Independent Claim
78 words
A method for making a microporous sheet which comprises coating a substrate with a hygroscopic solution containing a non-ionic polyurethane dissolved in a polar solvent therefor mixed with an aqueous dispersion or colloidal solution of either a cationic polyurethane or an anionic polyurethane and exposing the coating to moisture, said aqueous dispersion or said collodial solution being characterized as being sedimenting and redispersible, having a particle size of 0.8 to 100 microns, and being insoluble in boiling dimethylformamide.
References Cited (Backward Citations)
US3296190A
Cited
US3763054A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-04-24 | 1981-10-24 | 1982-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-04-24 | 1985-10-24 | 1986-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-04-24 | 1989-10-24 | 1990-04-25 | $7700.00 | Window Closed / Lapsed |