Phosphor suspension containing hydroxyethyl cellulose
Abstract
Abstract METHOD OF PREPARING A SUSPENSION IN A VEHICLE FOR USE INCLUDING DISCHARGE LAMP ENVELOPES, WHEREIN AN AQUEOUS SOLUTION OF HYDROXYETHYL CELLULOSE IS PREPARED, FILTERED AND PURIFIED BY USING A CATION ION EXCHANGE RESIN TO REMOVE THE SODIUM IONS OF THE SODIUM ACETATE IMPURITY, BUT LEEAVE THE ACETATE IONS. AMMONIUM HYDROXIDE IS THEN ADDED TO RAISE THE PH TP AT LEAST OF 6.5 AND TO REACT WITH THE ACETATE IONS TO FORM AMMONIUM ACETATE TO INHIBIT MOLD GROWTH. PREFERABLY AMMONIUM HYDROXIDE IS ADDED TO ESSENTIALLY NEUTRALIZE THE PURIFIED SOLUTION AND A BASIC SOLUTION SUCH AS TRIETHANOLAMINE IS THEN ADDED TO RAISE THE PH OF THE SOLUTION TO ABOUT 8.5-9.0, WHEREBY BACTERIA GROWTH IS INHIBITED.
Inventors
- 👤 R Repsher
- 👤 W Tarleton
- 👤 W Wilson
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
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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) | 1977-08-26 | 1978-02-25 | 1978-08-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-26 | 1982-02-25 | 1982-08-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-26 | 1986-02-25 | 1986-08-27 | $7700.00 | Window Closed / Lapsed |