Patent US2435840A successfully refreshed from Google Patents.
Patent US4205146A successfully refreshed from Google Patents.
US4205146A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the preparation of polyvinylbutyral having improved properties
Assignee: Hoechst AG
•
Filing: 1978-07-18
•
Granted: 1980-05-27
•
Expires: 1998-07-18
Abstract
Abstract The preparation of polyvinylbutyral is commonly effected by the acetalization of polyvinyl alcohol with n-butyraldehyde, either in an organic solvent or in water. By varying the reaction conditions it is possible to obtain the polyvinylbutyral in a coarse-grain or fine-grained form. The production of polyvinylbutyral having improved properties is possible by using a polyvinylbutyral having a content of from 17 to 24% by weight of vinyl alcohol units as starting material for an after-treatment in the presence of an organic sulfonic acid having an emulsifying effect. The polyvinylbutyral obtained is particularly suitable for the manufacture of compound sheets.
Inventors
- 👤 Hans D. Hermann
- 👤 Joachim Ebigt
- 👤 Ulrich M. Hutten
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:54
CPC Classifications
B; B32; B32B; B32B17/00; B32B17/06; B32B17/10; B32B17/10005; B32B17/1055; B32B17/10761; C; C08; C08F; C08F8/00; C08F8/48; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31551; Y10T428/31627; Y10T428/3163
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
150 words
Process for the preparation of a polyvinylbutyral having improved properties, which comprises subjecting a polyvinylbutyral having a viscosity of from 10 to 200 cp (measured according to DIN 53 015 at a 5% by weight solution in ethanol at 23° C.) and a content of from 17 to 24% by weight of vinyl alcohol units in an aqueous medium, at a temperature of from 50° to 70° C. in the presence of from 0.01 to 0.5% by weight, calculated on the polyvinylbutyral, of an organic sulfonic acid having from 8 to 30 carbon atoms and being effective as emulsifier to an acetalizing after-treatment for a period of from 0.5 to 10 hours in the presence of from 1 to 100 parts by weight of water per part of polyvinylbutyral and from 0.1 to 5% by weight of inorganic acid, calculated on the aqueous medium, and thereafter recovering the after-treated polyvinylbutyral.
Claim 2
Dependent Claim
150 words
Process for the preparation of a polyvinylbutyral having improved properties, which comprises subjecting a polyvinylbutyral having a viscosity of from 10 to 200 cp (measured according to DIN 53 015 at a 5% by weight solution in ethanol at 23° C.) and a content of from 17 to 24% by weight of vinyl alcohol units in an aqueous medium, at a temperature of from 50° to 70° C. in the presence of from 0.01 to 0.5% by weight, calculated on the polyvinylbutyral, of an organic sulfonic acid having from 8 to 30 carbon atoms and being effective as emulsifier to an acetalizing after-treatment for a period of from 0.5 to 10 hours in the presence of from 1 to 100 parts by weight of water per part of polyvinylbutyral and from 0.1 to 5% by weight of inorganic acid, calculated on the aqueous medium, and thereafter recovering the after-treated polyvinylbutyral.
Claim 3
Dependent Claim
37 words
Process as claimed in claim 1, which comprises using a polyvinylbutyral having a viscosity of from 50 to 100 cp (measured according to DIN 53 015 at a 5% by weight solution in ethanol at 23° C.)
Claim 4
Dependent Claim
25 words
Process as claimed in claim 1, which comprises using a polyvinylbutyral having a content of from 18 to 23% by weight of vinyl alcohol units.
Claim 5
Dependent Claim
20 words
Process as claimed in claim 1, which comprises heating the polyvinylbutyral in an aqueous medium to 50 to 65° C.
Claim 6
Dependent Claim
23 words
Process as claimed in claim 1, which comprises subjecting the polyvinylbutyral to an after-treatment for a period of from 1 to 7 hours.
Claim 7
Dependent Claim
27 words
Process as claimed in claim 1, which comprises using the organic sulfonic acid in an amount of from 0.05 to 0.2% by weight, calculated on the polyvinylbutyral.
Claim 8
Dependent Claim
36 words
A process as claimed in claim 1 wherein the after-treatment is applied to the polyvinylbutyral immedately after it has been initially prepared and without separating it from the original acetalization liquor in which it was prepared.
Claim 9
Dependent Claim
21 words
A process according to claim 1 wherein from 0.1 to 5% by weight of n-butyraldehyde is incorporated in the reaction medium.
References Cited (Backward Citations)
US3153009A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-05-27 | 1983-11-26 | 1984-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-05-27 | 1987-11-26 | 1988-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-05-27 | 1991-11-26 | 1992-05-27 | $7700.00 | Window Closed / Lapsed |