Patent US4332600A successfully refreshed from Google Patents.
US4332600A
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US
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Method for making silica fibers
Assignee: Ema Corp
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Filing: 1980-01-07
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Granted: 1982-06-01
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Expires: 2000-01-07
Abstract
Abstract Process for the production of silica fibers of the type in which alkali water glass is dry spun into water-containing alkali silicate fibers which are then contacted with solutions containing hydrogen ions for transforming into silica fibers, the improvement being dry-spinning glass free from non-alkaline compounds having a molar ratio of alkaline oxide to silic dry dioxide of from about 1:3 to 1:1.9 and a viscosity of about 10-700 Pa measured at 30° C., at 10°-50° C. in a drying funnel of a temperature of more than 100° C., at a discharge velocity of minimum 5 m/min.
Inventors
- 👤 Arno Wegerhoff
- 👤 Hans Zengel
- 👤 Walter Brodowski
- 👤 Heinz Beck
- 👤 Ernst Seeberger
- 👤 Gerhard Steenken
- 👤 Karlheinz Hillermeider
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 05:31
CPC Classifications
C; C03; C03B; C03B37/00; C03B37/01; C03B37/02; C03B37/03; B; B01; B01D; B01D39/00; B01D39/02; B01D39/06; B01D39/14; B01D39/20; B01D39/2003; B01D39/2017; C03B37/011; C03C; C03C13/00; C03C13/005; C04; C04B; C04B35/00; C04B35/622; C04B35/62227; C04B35/62231; C04B35/6224; D; D01; D01F; D01F9/00; D01F9/08; F; F16; F16D; F16D69/00; F16D69/02; F16D69/025; F16D69/026; F16D2200/00; F16D2200/006; F16D2200/0065; Y; Y02; Y02P; Y02P40/00; Y02P40/50; Y02P40/57; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2904; Y10T428/2913; Y10T428/2973; Y10T428/2975; Y10T428/298; Y10T442/00; Y10T442/60; Y10T442/696
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
129 words
In a process for the production of silica fibers of the type in which alkali water glass is dry spun into water-containing alkali silicate fibers which are then contacted with solutions containing hydrogen ions for transforming into silica fibers, the improvement comprising dry-spinning alkali water glass free from non-alkaline compounds, having a molar ratio of alkaline oxide to silicon dioxide of from about 1:3 to 1:1.9 and a viscosity of about 10 to 700 Pa measured at 30° C., at about 10° to 50° C. in a drying funnel of a temperature of more than 100° C. at a discharge velocity of minimum 5 m/min; and contacting the water-containing alkali silicate fibers with acid and/or salt solutions containing hydrogen ions for transforming the alkali silicate fibers into silica fibers.
Claim 2
Dependent Claim
129 words
In a process for the production of silica fibers of the type in which alkali water glass is dry spun into water-containing alkali silicate fibers which are then contacted with solutions containing hydrogen ions for transforming into silica fibers, the improvement comprising dry-spinning alkali water glass free from non-alkaline compounds, having a molar ratio of alkaline oxide to silicon dioxide of from about 1:3 to 1:1.9 and a viscosity of about 10 to 700 Pa measured at 30° C., at about 10° to 50° C. in a drying funnel of a temperature of more than 100° C. at a discharge velocity of minimum 5 m/min; and contacting the water-containing alkali silicate fibers with acid and/or salt solutions containing hydrogen ions for transforming the alkali silicate fibers into silica fibers.
Claim 3
Dependent Claim
79 words
The method of claim 1 wherein said dry-spinning includes jetting the alkali water glass having a temperature of from about 10° to 50° C. into a chamber filled with a gas of a temperature of more than 100° C. through jets with an exit velocity V 1 of at least about 5 m/min and drawing off the alkali silicate fibers with a drawing off velocity V 2 providing a stretch ratio V 2 /V 1 of at least 6.
Claim 4
Dependent Claim
12 words
The method of claim 1 further comprising thermally annealing the silica fibers.
Claim 5
Dependent Claim
12 words
The method of claim 1 wherein the alkaline oxide is sodium oxide.
Claim 6
Dependent Claim
33 words
The method of claim 1 wherein the alkaline oxide is a mixture comprising from 70 to 100 molar percent of sodium oxide and from about 0 to 30 molar percent of potassium oxide.
Claim 7
Dependent Claim
18 words
The method of claim 2 wherein the drawing off velocity v 2 is at least about 60 m/min.
Claim 8
Dependent Claim
18 words
The method of claim 2 wherein the drawing off velocity v 2 is at least about 300 m/min.
Claim 9
Dependent Claim
22 words
The method of claim 1 wherein said alkali silicate fibers have a water content of from about 15 to 30 weight percent.
Claim 10
Dependent Claim
21 words
The method of claim 2 wherein the spinning material is at a temperature of from about 20° C. to 35° C.
Claim 11
Dependent Claim
24 words
The method of claim 1 wherein the spinning material has a viscosity of from about 100 Pa.s to 400 Pa.s measured at 30° C.
Claim 12
Dependent Claim
22 words
The method of claim 1 wherein said alkali silicate fibers have a water content of from about 20 to 50 weight percent.
Claim 13
Dependent Claim
31 words
The method of claim 1 wherein the alkaline oxide comprises from about 70 to 100 mole percent of sodium oxide and from about 0 to 30 mole percent of potassium oxide.
Claim 14
Dependent Claim
21 words
The method of claim 1 wherein said alkali silicate fibers have a tear strength of from about 5 to 30 cN/tex.
Claim 15
Dependent Claim
21 words
The method of claim 1 wherein said alkali silicate fibers have a tear strength of from about 15 to 25 cN/tex.
Claim 16
Dependent Claim
23 words
The method of claim 1 wherein contacting is done with a 0.5 to 5 n aqueous hydrochloric acid solution at about room temperature.
Claim 17
Dependent Claim
29 words
The method of claim 1 wherein contacting is done with an about 0.8 to 1.5 n aqueous hydrochloric acid solution at a temperature from about 20° to 90° C.
Claim 18
Dependent Claim
38 words
The method of claim 1 wherein the aqueous acid and/or salt solution is a solution of ammonium chloride in water having a pH of from about 1 to 8 and an at least 1 normal chloride ion concentration.
Claim 19
Dependent Claim
11 words
The method of claim 1 further comprising: washing the silica fibers.
Claim 20
Dependent Claim
13 words
The method of claim 18 further comprising drying after washing the silica fibers.
Claim 21
Dependent Claim
19 words
The method of claim 3 wherein the thermal annealing is performed at temperatures from about 200° to 1000° C.
Claim 22
Dependent Claim
21 words
The method of claim 3 wherein the thermal annealing is performed at temperatures of from about 500° C. to 1000° C.
Claim 23
Dependent Claim
21 words
The method of claim 3 wherein the thermal anneaing is performed at temperatures of from about 600° C. to 900° C.
Claim 24
Dependent Claim
18 words
The method of claim 1 further comprising cutting the silicon dioxide fibers to 1 to 40 mm length.
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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) | 1985-05-31 | 1985-11-30 | 1986-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-05-31 | 1989-11-30 | 1990-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-05-31 | 1993-11-30 | 1994-06-01 | $7700.00 | Window Closed / Lapsed |