Controlled-release type fertilizer with decreased floating property comprising tri-block copolymer and method for preparing the same

Patent metadata

Field	Value
Publication number	US-11370719-B2
Application number	US-201816646959-A
Country	US
Kind code	B2
Filing date	Sep 13, 2018
Priority date	Sep 13, 2017
Publication date	Jun 28, 2022
Grant date	Jun 28, 2022

Abstract

The present invention relates to a controlled-release type fertilizer with outstandingly decreased floating property, comprising a granular fertilize core; a coating layer (shell) formed on the surface of the granular fertilizer core, and comprising olefin-based resin; and additives attached on the coating layer, and comprising ethylene oxide-propylene oxide-ethylene oxide(EO-PO-EO) or propylene oxide-ethylene oxide-propylene oxide(PO-EO-PO) tri-block copolymer.

First claim

The invention claimed is:

1. A controlled-release type fertilizer comprising:
a granular fertilizer core;
a coating layer formed on the surface of the granular fertilizer core, the coating layer comprising an olefin-based resin; and
additives attached on the coating layer, the additives comprising an ethylene oxide-propylene oxide-ethylene oxide(EO-PO-EO) tri-block copolymer or a propylene oxide-ethylene oxide-propylene oxide(PO-EO-PO) tri-block copolymer,
wherein the ethylene oxide-propylene oxide-ethylene oxide (EO-PO-EO) or the propylene oxide-ethylene oxide-propylene oxide (PO-EO-PO) tri-block copolymer has a HLB value of 1 to 10, and
the ethylene oxide block in the tri-block copolymer is included in an amount of 5 to 50 wt % based on the total weight of the tri-block copolymer.

2. The controlled-release type fertilizer according to claim 1 , wherein the olefin-based resin is polyolefin or a copolymer of olefin and ethylene vinyl acetate.

3. The controlled-release type fertilizer according to claim 1 , wherein the propylene oxide block in the tri-block copolymer has a weight average molecular weight of 950 to 4,000.

4. The controlled-release type fertilizer according to claim 1 , wherein the ethylene oxide block in the tri-block copolymer has a weight average molecular weight of 50 to 2,000.

5. The controlled-release type fertilizer according to claim 1 , comprising 0.025 wt % to 0.5 wt % of the additives based on the weight of the controlled-release type fertilizer.

6. The controlled-release type fertilizer according to claim 1 , wherein the additives further comprise inorganic powder.

7. The controlled-release type fertilizer according to claim 6 , wherein the inorganic powder has a specific surface area of 100 m 2 /g to 500 m 2 /g.

8. The controlled-release type fertilizer according to claim 6 , wherein the inorganic powder has a particle size of 1 μm to 500 μm.

9. The controlled-release type fertilizer according to claim 6 , wherein the inorganic powder is hydrophilic inorganic powder having a hydroxyl group.

10. The controlled-release type fertilizer according to claim 6 , wherein the inorganic powder is included in the amount of 0.01 wt % to 1 wt %, based on the weight of the controlled-release type fertilizer.

11. The controlled-release type fertilizer of claim 1 , wherein the ethylene oxide-propylene oxide-ethylene oxide(EO-PO-EO) or propylene oxide-ethylene oxide-propylene oxide(PO-EO-PO) tri-block copolymer has a HLB value of 1 to 5, and wherein a weight average molecular weight of the propylene oxide block is 1500 to 4000.

12. The controlled-release type fertilizer of claim 1 , wherein the coating layer is a shell covering the granular fertilizer core and the additives are uniformly attached to the surface of the shell.

13. A method for preparing a controlled-release type fertilizer, comprising the steps of:
i) coating the surface of a granular fertilizer core with a coating composition comprising an olefin-based resin to form a first coating layer; and
ii) coating the first coating layer with liquid additives comprising an ethylene oxide-propylene oxide-ethylene oxide(EO-PO-EO) tri-block copolymer or a propylene oxide-ethylene oxide-propylene oxide(PO-EO-PO) tri-block copolymer,
wherein the ethylene oxide-propylene oxide-ethylene oxide (EO-PO-EO) or the propylene oxide-ethylene oxide-propylene oxide (PO-EO-PO) tri-block copolymer has a HLB value of 1 to 10, and
the ethylene oxide block in the tri-block copolymer is included in an amount of 5 to 50 wt % based on the total weight of the tri-block copolymer.

14. The method of claim 13 , wherein the coating step (ii) comprises adding the liquid additives in an amount of 0.025 wt % to 0.5 wt % based on the weight of the controlled-release type fertilizer.

15. The method of claim 13 , wherein the first coating layer in step (i) is a shell covering the granular fertilizer core.

Assignees

• Lg Chemical Ltd

Inventors

• KIM Mihee
• Joo Hyosook
• Park Eun Kyoung
• Choi Hyeon
• Yoon Kiyoul
• Lee Joon Seok

Classifications

• C05C9/005 Primary

  Post-treatment · CPC title

• C05G5/30

  Layered or coated, e.g. dust-preventing coatings · CPC title

• C05G5/37

  layered or coated with a polymer · CPC title

• C05G3/44 Primary

  for affecting solubility · CPC title

• C05G5/38

  layered or coated with wax or resins · CPC title