Patent US4339479A successfully refreshed from Google Patents.
US4339479A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Treatment of cellulose
Assignee: Individual
•
Filing: 1974-12-20
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Granted: 1982-07-13
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Expires: 1994-12-20
Abstract
Abstract A process for rendering cellulosic material water repellent that requires no subsequent neutralization step while retaining the desired water repellent and strength characteristics thus provided by selecting a cellulosic material having a water content of up to about 10%, preferably below about 2% and contacting the material with vapors of a lower alkyl silicon halide during which contacting the concentration and temperature of the halide vapor, the pressure within the treating chamber and the contact time are all maintained so as to provide a water repellent cellulosic material having a pH greater than 2.5. In one aspect of the invention, the cellulosic material subjecting to contacting is substantially frozen and in another aspect contacting is conducted under vacuum.
Inventors
- 👤 Edward Robbart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 03:08
CPC Classifications
D; D06; D06M; D06M13/00; D06M13/50; D06M13/51; D06M13/513; D21; D21H; D21H17/00; D21H17/03; D21H17/05; D21H17/13
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
186 words
A process for rendering a cellulosic material water repellent by treatment with vapors of lower alkyl silicon halide without the need of a neutralization step while retaining the strength characteristics of the material which consists essentially of contacting in a contact chamber at a contact chamber pressure of about 1 Torr to 16.7 psi a cellulosic material having a water content of up to about 10 weight percent with vapors of a lower alkyl silicon halide which reacts with hydroxyl groups to form a siloxane, said vapors being at a temperature of ambient room temperature to 180° F. and a concentration of about 0.5 volume percent up to the saturation of the contacting atmosphere, and a contact time of from 0.1 second up to 30 minutes, maintaining the concentration of lower alkyl silicon halide in the contacting atmosphere, the temperature of said lower alkyl silicon halide vapor, the pressure within said treating chamber, the temperature of the cellulosic material, and the contact time so that the cellulosic material contacted with the lower alkyl silicon halide is rendered water repellent and has a pH greater than 3.5.
Claim 2
Dependent Claim
186 words
A process for rendering a cellulosic material water repellent by treatment with vapors of lower alkyl silicon halide without the need of a neutralization step while retaining the strength characteristics of the material which consists essentially of contacting in a contact chamber at a contact chamber pressure of about 1 Torr to 16.7 psi a cellulosic material having a water content of up to about 10 weight percent with vapors of a lower alkyl silicon halide which reacts with hydroxyl groups to form a siloxane, said vapors being at a temperature of ambient room temperature to 180° F. and a concentration of about 0.5 volume percent up to the saturation of the contacting atmosphere, and a contact time of from 0.1 second up to 30 minutes, maintaining the concentration of lower alkyl silicon halide in the contacting atmosphere, the temperature of said lower alkyl silicon halide vapor, the pressure within said treating chamber, the temperature of the cellulosic material, and the contact time so that the cellulosic material contacted with the lower alkyl silicon halide is rendered water repellent and has a pH greater than 3.5.
Claim 3
Dependent Claim
19 words
The process of claim 1 wherein the water content of said cellulosic material is below about 2% by weight.
Claim 4
Dependent Claim
20 words
The process of claim 1 wherein the water content of said cellulosic material is 0 to about 1 weight percent.
Claim 5
Dependent Claim
18 words
The process of claim 1 wherein the water content of said cellulosic material is about 0 weight percent.
Claim 6
Dependent Claim
11 words
The process of claim 1 wherein the cellulosic material is paper.
Claim 7
Dependent Claim
11 words
The process of claim 1 wherein the cellulosic material is paper.
Claim 8
Dependent Claim
12 words
The process of claim 1 wherein the cellulosic material is a textile.
Claim 9
Dependent Claim
12 words
The process of claim 4 wherein the cellulosic material is a textile.
Claim 10
Dependent Claim
48 words
The process of claim 1 wherein the said cellulosic material is contacted with a mixture of vapors of the lower alkyl silicon halide and vapors of a solvent for the lower alkyl silicon halide which solvent is non-reactive with the lower alkyl silicon halide or the cellulosic material.
Claim 11
Dependent Claim
48 words
The process of claim 8 wherein the said cellulosic material is contacted with a mixture of vapors of the lower alkyl silicon halide and vapors of a solvent for the lower alkyl silicon halide which solvent is non-reactive with the lower alkyl silicon halide or the cellulosic material.
Claim 12
Dependent Claim
48 words
The process of claim 1 wherein the cellulosic material is removed from contact with the lower alkyl silicon halide and is heated to remove hydrogen halide from the cellulosic material prior to a substantial portion of said hydrogen halide being dissolved in water contained in the cellulosic material.
Claim 13
Dependent Claim
17 words
The process of claim 1 wherein the cellulosic material subjected to said contacting is below ambient temperature.
Claim 14
Dependent Claim
16 words
The process of claim 1 wherein the cellulosic material subjected to said contacting is substantially frozen.
Claim 15
Dependent Claim
48 words
The process of claim 13 wherein the cellulosic material is removed from contact with the lower alkyl silicon halide and is heated to remove hydrogen halide from the cellulosic material prior to a substantial portion of said hydrogen halide being dissolved in water contained in the cellulosic material.
Claim 16
Dependent Claim
13 words
The process of claim 1 wherein the contacting is conducted under subatmospheric pressure.
Claim 17
Dependent Claim
12 words
The process of claim 4 wherein the contacting is conducted under vacuum.
Claim 18
Dependent Claim
48 words
The process of claim 16 wherein the cellulosic material is removed from contact with the lower alkyl silicon halide and is heated to remove hydrogen halide from the cellulosic material prior to a substantial portion of said hydrogen halide being dissolved in water contained in the cellulosic material.
Claim 19
Dependent Claim
19 words
The process of claim 1 wherein said lower alkyl silicon halide comprises a methylchlorosilane or a mixture of methylchlorosilanes.
Claim 20
Dependent Claim
19 words
The process of claim 1 wherein said lower alkyl silicon halide comprises a methylchlorosilane or a mixture of methylchlorosilanes.
Claim 21
Dependent Claim
19 words
The process of claim 13 wherein said lower alkyl silicon halide comprises a methylchlorosilane or a mixture of methylchlorosilanes.
Claim 22
Dependent Claim
19 words
The process of claim 16 wherein said lower alkyl silicon halide comprises a methylchlorosilane or a mixture of methylchlorosilanes.
Claim 23
Dependent Claim
67 words
The process of claim 3 wherein the temperature of the vapors is ambient room temperature to 150° F., the temperature of the cellulosic material is frozen to ambient room temperature, the concentration of the vapors is 4 volume percent up to the saturation of the contacting atmosphere, the contact time is in excess of 7 seconds and the contact chamber pressure is 3 Torr to atmospheric pressure.
Claim 24
Dependent Claim
54 words
The process of claim 13 wherein the temperature of the vapors is ambient room temperature to 150° C., the concentration of the vapors is 1/2 volume % up to the saturation of the contacting atmosphere, the contact time is 0.1 to 30 seconds, and the contact chamber pressure is 3 Torr to atmospheric pressure.
Claim 25
Dependent Claim
55 words
The process of claim 15 wherein the temperature of the vapors is ambient room temperature to 150° C., the concentration of the vapors is 1/2 volume percent up to the saturation of the contacting atmosphere, the temperature of the paper is frozen to ambient room temperature and the contact time is 1 to 10 minutes.
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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) | 1985-07-12 | 1986-01-11 | 1986-07-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-07-12 | 1990-01-11 | 1990-07-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-07-12 | 1994-01-11 | 1994-07-13 | $7700.00 | Window Closed / Lapsed |