Patent US3937672A successfully refreshed from Google Patents.
US3937672A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the manufacture of consolidated shaped structures of cellulose hydrate
Assignee: Hoechst AG
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Filing: 1973-09-20
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Granted: 1976-02-10
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Expires: 1993-09-20
Abstract
Abstract This invention relates to a process for the preparation of a cellulose hydrate moulding which comprises (a) treating a cellulose hydrate moulding while in the gel state, for a period within the range of from 10 seconds to 20 minutes, with an aqueous liquid having dissolved therein at least one plasticizer, a chemical cross-linking agent comprising at least one cyclic urea compound having at least 2 N-methylol groups, and at least one cross-linking catalyst, (b) drying the moulding to a residual water content of from 8 to 12% by weight, and (c) heating the moulding at a temperature within the range of from 100° to 150°C for a period of from 30 seconds to 20 minutes. The invention also relates to a cellulose hydrate moulding prepared by the novel process.
Inventors
- 👤 Walter Busch
- 👤 Klaus-Dieter Hammer
- 👤 Wolfgang Klendauer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:55
CPC Classifications
C; C08; C08B; C08B15/00; C08B15/10; A; A22; A22C; A22C13/00; A22C13/0013; C08K; C08K5/00; C08K5/16; C08K5/21
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
152 words
A process for the preparation of a cellulose hydrate moulding which comprises a. treating a cellulose hydrate moulding while in the gel state, for a period within the range of from 10 seconds to 20 minutes, with an aqueous liquid having a pH value of less than 7 and having dissolved therein at least one plasticizer, a chemical cross-linking agent comprising at least one cyclic urea compound having at least 2 N-methylol groups and being present in an amount of 0.5 to 15% relative to the weight of the plasticizer solution, and at least one cross-linking catalyst selected from the group consisting of an acid and an acid salt, b. drying the moulding to a residual water content of from 8 to 12% by weight, and c. heating the moulding at a temperature within the range of from 100° to 150° C for a period of from 30 seconds to 20 minutes.
Claim 2
Dependent Claim
152 words
A process for the preparation of a cellulose hydrate moulding which comprises a. treating a cellulose hydrate moulding while in the gel state, for a period within the range of from 10 seconds to 20 minutes, with an aqueous liquid having a pH value of less than 7 and having dissolved therein at least one plasticizer, a chemical cross-linking agent comprising at least one cyclic urea compound having at least 2 N-methylol groups and being present in an amount of 0.5 to 15% relative to the weight of the plasticizer solution, and at least one cross-linking catalyst selected from the group consisting of an acid and an acid salt, b. drying the moulding to a residual water content of from 8 to 12% by weight, and c. heating the moulding at a temperature within the range of from 100° to 150° C for a period of from 30 seconds to 20 minutes.
Claim 3
Dependent Claim
19 words
A process as claimed in claim 1 wherein the aqueous liquid has a pH value of less than 5.
Claim 4
Dependent Claim
23 words
A process as claimed in claim 1 wherein the aqueous liquid is at a temperature within the range of from 40° to 80°C.
Claim 5
Dependent Claim
23 words
A process as claimed in claim 3 wherein the aqueous liquid is at a temperature within the range of from 60° to 80°C.
Claim 6
Dependent Claim
23 words
A process as claimed in claim 1 wherein the concentration of plasticizer in the aqueous liquid is from 10 to 12% by weight.
Claim 7
Dependent Claim
18 words
A process as claimed in claim 1 wherein the plasticizer comprises at least one glycol, polyglycol, or glycerol.
Claim 8
Dependent Claim
24 words
A process as claimed in claim 1 wherein the concentration of cross-linking agent in the aqueous liquid is from 0.5 to 15% by weight.
Claim 9
Dependent Claim
20 words
A process as claimed in claim 7 wherein the concentration of cross-linking agent is from 1 to 8% by weight.
Claim 10
Dependent Claim
28 words
A process as claimed in claim 1 wherein the cross-linking catalyst is present in an amount of from 1 to 5% by weight relative to the cross-linking agent.
Claim 11
Dependent Claim
14 words
A process as claimed in claim 1 wherein the cross-linking catalyst comprises an acid.
Claim 12
Dependent Claim
37 words
A process as claimed in claim 10 wherein the cross-linking catalyst comprises at least one acid selected from the group consisting of sulfuric acid, hydrochloric acid, acetic acid, tartaric acid, oxalic acid, propionic acid and formic acid.
Claim 13
Dependent Claim
15 words
A process as claimed in claim 1 wherein the cross-linking catalyst comprises an acid salt.
Claim 14
Dependent Claim
29 words
A process as claimed in claim 12 wherein the cross-linking catalyst comprises at least one salt selected from ammonium chloride, ammonium acetate, magnesium chloride, zinc chloride and zinc nitrate.
Claim 15
Dependent Claim
19 words
A process as claimed in claim 10 wherein the cross-linking catalyst comprises both an acid and an acid salt.
Claim 16
Dependent Claim
13 words
A process as claimed in claim 1 wherein the cross-linking agent comprises dimethylol-ethyleneurea.
Claim 17
Dependent Claim
13 words
A process as claimed in claim 1 wherein the cross-linking agent comprises dimethylol-dihydroxy-ethyleneurea.
Claim 18
Dependent Claim
25 words
A process as claimed in claim 1 wherein step (a) is carried out for a period within the range of from 10 to 40 seconds.
Claim 19
Dependent Claim
24 words
A process as claimed in claim 1 wherein step (b) is carried out at a temperature within the range of from 70° to 100°C.
Claim 20
Dependent Claim
25 words
A process as claimed in claim 1 wherein step (b) is carried out for a period within the range of from 1 to 20 minutes.
Claim 21
Dependent Claim
13 words
A cellulose hydrate moulding prepared by a process as claimed in claim 1.
Claim 22
Dependent Claim
18 words
An artificial sausage casing comprising a cellulose hydrate tube prepared by a process as claimed in claim 1.
Claim 23
Dependent Claim
42 words
A process as claimed in claim 1 wherein the cross-linking agent is a cyclic urea derivate containing at least two N-methylol groups, selected from the series consisting of dimethylolethyleneurea (1,3-dimethylol-imidazolid-2-one), dimethyloldihydroxy-ethyleneurea (1,3-dimethylol-4,5-dihydroxy-imidazolid-2-one), dimethylol-ethyl-triazinone, 3,5-dimethylol-3,5-diazatetra-hydropyrone-4, tetramethylol-acetylene-diurea, dimethylolpropylene-urea dimethylol-hydroxypropylene-urea, dimethylol-tetramethylpropylene-urea, and 1-(glycol-monomethyl ether)-2-dimethylol carbamate.
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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) | 1979-02-09 | 1979-08-11 | 1980-02-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-02-09 | 1983-08-11 | 1984-02-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-02-09 | 1987-08-11 | 1988-02-10 | $7700.00 | Window Closed / Lapsed |