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US4074989A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of preparing anhydrous boric acid-containing glass batch

Assignee: PPG Industries Inc
•
Filing: 1976-11-08
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Granted: 1978-02-21
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Expires: 1996-11-08
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Abstract

Abstract A process is described for preparing anhydrous boric acid (ABA)-containing glass batch compositions suitable for the preparation of glass fibers in which the batch, prior to its introduction into the furnace, is pelletized by adding water in sufficient quantities to maintain an adequate balling action and thus provide pellets in a form such that preheating by direct contact with flue gases does not cause deterioration of the pellets.

Inventors

  • 👤 Stanley F. Brzozowski
  • 👤 Joseph E. Cooper

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 10:02
CPC Classifications
C; C03; C03C; C03C13/00; C03B; C03B1/00; C03B1/02; Y; Y02; Y02P; Y02P40/00; Y02P40/50

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 84 words
A method of preparing an anhydrous boric acid-containing glass fiber forming glass batch having a substantial amount of alumina therein comprising introducing anhydrous boric acid-containing batch ingredients into a pelletizing zone, agglomerating the ingredients with sufficient water to produce pellets containing about 10-25 percent free water by weight, heating the pellets at a temperature of at least 450° F. (232.2° C.) and drying the pellets at that temperature for a period of time sufficient to thereby prevent disintegration thereof and produce hard, nondusting pellets.
Claim 2
Independent Claim 84 words
A method of preparing an anhydrous boric acid-containing glass fiber forming glass batch having a substantial amount of alumina therein comprising introducing anhydrous boric acid-containing batch ingredients into a pelletizing zone, agglomerating the ingredients with sufficient water to produce pellets containing about 10-25 percent free water by weight, heating the pellets at a temperature of at least 450° F. (232.2° C.) and drying the pellets at that temperature for a period of time sufficient to thereby prevent disintegration thereof and produce hard, nondusting pellets.
Claim 3
Dependent Claim 15 words
The method of claim 1 wherein said pelletizing zone comprises an inclined, rotating disc pelletizer.
Claim 4
Dependent Claim 24 words
The method of claim 1 wherein said pellets are produced having nominal diameters of between about 0.375 and 0.625 inch (0.9525 and 1.5875 centimeters).
Claim 5
Dependent Claim 20 words
The method of claim 1 wherein the pellets are dried to about 1 percent or less by weight free water.
Claim 6
Dependent Claim 15 words
The method of claim 1 wherein the free water is approximately 15-17 percent by weight.

References Cited (Backward Citations)

US2334961A Cited
US2366473A Cited
US3001881A Cited
US2976162A Cited
US3287095A Cited
US3274006A Cited
US3887671A Cited
US3880639A Cited
US3914364A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-02-20 1981-08-22 1982-02-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-02-20 1985-08-22 1986-02-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-02-20 1989-08-22 1990-02-21 $7700.00 Window Closed / Lapsed

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