Scorch-resistant water-soluble flame-retardants for cellulose
Abstract
Abstract Cellulosic materials are made flame retardant, while minimizing the scorching and loss of strength of such materials when heated, by applying thereto a composition, preferably in aqueous solution, consisting essentially of at least one sodium or potassium salt of orthophosphoric acid or the various polymeric phosphoric acids, and at least one guanidine, guanylurea or biguanide salt of hydrochloric, hydrobromic, sulfuric, sulfamic or phosphoric acid, with the proportion, by weight, of the sodium or potassium salt to the guanidine, guanylurea or biguanide salt being in the range from 1:5 to 5:1, and with the total dry add-on of the composition being from 5 to 30 percent of the weight of the cellulosic material being treated therewith. The guanidine, guanylurea or biguanide salt constituent of the flame retardant composition may be provided in the form of the product of the condensation reaction of dicyandiamide with at least one of ammonium chloride, bromide, sulfamate or sulfate.
Inventors
- 👤 A Endler
Bibliographic Details
Claims Analysis
Total Claims: 3References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-24 | 1977-12-24 | 1978-06-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-24 | 1981-12-24 | 1982-06-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-24 | 1985-12-24 | 1986-06-25 | $7700.00 | Window Closed / Lapsed |