Coating compositions for slow release fertilizer formulations

• US 5,264,019 A
• Filed: 03/05/1991
• Issued: 11/23/1993
• Est. Priority Date: 03/05/1991
• Status: Expired due to Fees

• Current Assignee: Eastman Chemical Company
• Original Assignee: Eastman Kodak Company
• Inventors: Gossett, John R. Jr., Kirk, Shane K., Smith, E. Phillip
• Primary Examiner(s): Lander, Ferris
• Application Number:
  US07/664,719
• Time in Patent Office: 994 Days
• Field of Search: 71/64.11, 71/64.07, 71/64.13, 524/272, 524/476
• US Class Current: 71/64.07
• CPC Class Codes: C05G 5/30 Layered or coated, e.g. dust-preventing coatings
• CPC Class Codes: C05G 5/38 layered or coated with wax or resins

Abstract

Coating compositions containing medium density, low molecular weight polyethylene wax and a tackifying resin. The coating composition coats a fertilizer core such as urea to result in an improved fertilizer release profile.

Claims

1. A fertilizer composition comprising:

(1) a core fertilizer material comprising at least one soluble salt of nitrogen, potassium, or phosphorous, and

(2) a coating composition surrounding said core wherein said coating composition comprises;

(A) about 75% to about 95% of a polyethylene wax having a molecular weight of about 2,000 to about 4,000, and a density of about 0.92 to about 0.94 g/ml, and

(B) about 5% to about 25% of a tackifying resin consisting of a hydrogenated C₅ hydrocarbon resin having a molecular weight of about 700 to about 1,200 and a Ring and Ball softening point of about 80°

C. to about 150°

C.,

said percentages being based on the total weight of components (A) plus (B).

2. The fertilizer composition of claim 1 wherein said core is comprised of urea.

3. The fertilizer composition of claim 1 wherein component (2) is present in an amount of about 5 to about 40%, based on the weight of component (1).

4. The fertilizer composition of claim 1 wherein component (A) is present in an amount of about 80% to about 90% and component (B) is present in an amount of about 10% to about 20%.

5. The fertilizer composition of claim 1 wherein said polyethylene wax has a molecular weight of about 2,500 to about 3,500 and said tackifying resin has a molecular weight of about 800 to about 1,000 and a Ring and Ball softening point of about 90°

C. to about 140°

C.

6. The fertilizer composition of claim 1 wherein said polyethylene wax has a density of about 0.925 g/ml.

7. The fertilizer composition of claim 6 wherein said tackifying resin has a molecular weight of about 850 to about 1,025 and a Ring and Ball softening point of about 100°

C. to about 130°

C.

8. The fertilizer composition of claim 7 comprising about 80% of component (A) and about 20% of component (B).

9. The fertilizer composition of claim 1 wherein said tackifying resin has a molecular weight of about 850 to about 1,025 and a Ring and Ball softening point of about 100°

C. to about 130°

C.

10. The fertilizer composition of claim 1 wherein said coating composition further comprises about 1 to about 50%, based on the total weight of the coating composition, of at least one additional additive selected from the group consisting of talc, TiO₂, and CaCO₃.