US3762909A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Phosphorus borate glass frits as plant micro nutrient carriers
Assignee: STEEL CORPUS
•
Filing: 1971-06-10
•
Granted: 1973-10-02
•
Expires: 1991-06-10
Abstract
Abstract Vitreous compositions of phosphorus-borate glass and oxides of various metals fused and adapted to cause a slow release of nutrient materials to plants and a process for their production.
Inventors
- 👤 W Davie
- 👤 L Green
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 06:40
CPC Classifications
C; C05; C05D; C05D9/00; C05D9/02; C03; C03C; C03C3/00; C03C3/12; C03C3/16; C03C3/19; C03C4/00; C03C4/0035; C05B; C05B13/00; C05B13/06; Y; Y10; Y10S; Y10S71/00; Y10S71/904
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
18 words
The composition of claim 1 wherein the ratio of said metal cations to phosphate anion is about 1:1.
Claim 2
Dependent Claim
25 words
A mixed fertilizer comprising a source of potassium, phosphorous, and nitrogen as a major component and the composition of claim 1 as a minor component.
Claim 3
Dependent Claim
207 words
A fertilizer composition for imparting micronutrients, phosphorous and boron to soil and having a boron release rate of less than 8.3 percent by weight, a micronutrient release rate of less than 0.010 percent by weight and at least 75 percent available phosphorous, said composition being obtained by the steps of: a. preparing a mixture of water insoluble micronutrient source, a water soluble borate, and a phosphate consisting of a mixture of sodium metaphosphate and metaphosphoric acid, said micronutrient source being selected from the group consisting of the oxides and carbonates of copper, iron, manganese, molybdenum, zinc, magnesium, calcium and mixtures thereof, said borate being present in an amount of about 2 percent by weight by weight calculated as Na2B4O2.1OH2O, said phosphate being present in an amount of about 51 percent by weight, said micronutrient source being the remainder, and the molar ratio of the sum of the metal cation in the borate and the metal cation in the phosphate to the phosphate anion is between 1:2 and 2:1, b. fusing said mixture to a homogeneous mass at a temperature of 900* to 1,000* C, c. quickly quenching said mixture to produce a frit, and d. grinding said frit and recovering sizes from 200 mesh to 40 mesh.
Claim 4
Dependent Claim
18 words
The composition of claim 4 wherein the ratio of said metal cations to phosphate anion is about 1:1.
Claim 5
Dependent Claim
25 words
A mixed fertilizer comprising a source of potassium, phosphorous and nitrogen as a major component and the composition of claim 4 as a minor component.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-01 | 1977-04-02 | 1977-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-01 | 1981-04-02 | 1981-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-01 | 1985-04-02 | 1985-10-02 | $7700.00 | Window Closed / Lapsed |