Preparation of corrosion-protective copper paste through single process and application thereof to dipole tag antenna

Patent metadata

Field	Value
Publication number	US-9945038-B2
Application number	US-201414909919-A
Country	US
Kind code	B2
Filing date	May 27, 2014
Priority date	Nov 18, 2013
Publication date	Apr 17, 2018
Grant date	Apr 17, 2018

Abstract

Provided are a method of producing corrosion-protective copper paste through a single process and an application thereof to a dipole tag antenna. Copper powder is surface-etched by using a hydrochloric acid in an inert gas atmosphere, a phosphoric acid aqueous solution is added thereto to form copper phosphate on the etched surface of the copper powder, and then, a vinyl imidazole-silane copolymer and poly(4-styrenesulfonate) were introduced thereto to form a corrosion-protective coating layer on the surface of copper powder on which the copper phosphate has been formed, and a centrifuge and an agate mortar are used to prepare a copper paste having high viscosity and high dispersability. When a copper paste thin film is formed on a flexible film by screen printing, a produced dipole tag antenna may have high efficiency.

First claim

What is claimed is:

1. A method of preparing a copper paste for a dipole tag antenna, the method comprising:
etching a surface of copper powder by introducing a hydrochloric acid aqueous solution to the copper powder in an inert gas atmosphere;
forming copper phosphate by introducing a phosphoric acid aqueous solution to the surface of the copper powder that has been etched;
forming a corrosion-protective coating layer by adding a vinyl imidazole-silane copolymer and a poly(4-styrenesulfonate) aqueous solution to the copper powder on which the copper phosphate has been formed, and
using a centrifuge and an agate mortar, with respect to the copper powder on which the corrosion-protective coating layer has been formed.

2. The method of claim 1 , wherein the copper powder is in a pattern selected from a flake pattern, a sphere pattern, a bead pattern, and a dendrite pattern.

3. The method of claim 1 , wherein a volume of the copper powder is at most half a volume of a reactor.

4. The method of claim 1 , wherein a volume of the hydrochloric acid aqueous solution is in a range of 1 ml to 2 ml per 1 g of the copper powder.

5. The method of claim 1 , wherein a concentration of the phosphoric acid aqueous solution is in a range of 1 M to 2 M.

6. The method of claim 1 , wherein a volume of the phosphoric acid aqueous solution is in a range of 3 ml to 5 ml per 1 g of the copper powder.

7. The method of claim 1 , wherein when a copolymerization is performed to produce the vinyl imidazole-silane copolymer, a volume of a silane monomer is in a range of 5 parts by volume to 20 parts by volume based on 100 parts by volume of vinyl imidazole and the silane monomer.

8. The method of claim 1 , wherein when a copolymerization is performed to produce the vinyl imidazole-silane copolymer, a concentration of an initiator is in a range of 0.05 parts by weight to 0.5 parts by weight based on 100 parts by weight of vinyl imidazole and a silane monomer.

9. The method of claim 1 , wherein when the vinyl imidazole-silane copolymer is formed, a copolymerization time is in a range of 12 hours to 24 hours.

10. The method of claim 1 , wherein when the vinyl imidazole-silane copolymer is formed, a reaction temperature is in a range of 50° C. to 70° C.

11. The method of claim 1 , wherein a volume of the vinyl imidazole-silane copolymer is in a range of 0.5 ml to 1 ml based on 1 g of the copper powder.

12. The method of claim 1 , wherein when the poly(4-styrenesulfonate) aqueous solution is subjected to a radical polymerization, a ratio of an initiator is in a range of 0.1 mol to 0.2 mol based on 100 mol of a styrenesulfonate monomer.

13. The method of claim 1 , wherein when the poly(4-styrenesulfonate) aqueous solution is subjected to a polymerization, a reaction temperature is in a range of 40° C. to 50° C.

14. The method of claim 1 , wherein the poly(4-styrenesulfonate) aqueous solution is subjected to a polymerization, a reaction time is in a range of 6 hours to 24 hours.

15. The method of claim 1 , wherein a volume of the poly(4-styrenesulfonate) aqueous solution is in a range of 0.5 ml to 1 ml based on 1 g of the copper powder.

16. The method of claim 1 , wherein a stirring time for forming the corrosion-protective coating layer is in a range of 1 hour to 3 hours.

17. The method of claim 1 , wherein when centrifuging is performed using the centrifuge, the speed of the centrifuge is in a range of 5,000 rpm to 10,000 rpm.

18. The method of claim 1 , wherein when centrifuging is performed using the centrifuge, a precipitation time of the copper paste is in a range of 5 minutes to 30 minutes.

19. The method of claim 1 , wherein when centrifuging is performed using the centrifuge, a centrifuging product is re-distributed in ethanol.

20. A copper paste embodied by using the method of claim 1 .

21. A method of producing a dipole tag antenna comprising copper paste, the method comprising the method of claim 1 to embody the copper paste.

22. The method of claim 21 , wherein a film used to produce the dipole tag antenna comprises any one of polyethyleneterephthalate and polyimide.

23. The method of claim 21 , wherein when screen printing is performed to produce the dipole tag antenna, a mask used has fine mesh having 270 pores to 300 pores within an interval of 1 centimeter.

24. The method of claim 21 , wherein when the dipole tag antenna is produced, a thickness of the copper paste thin film is at most 30 micrometers.

Assignees

• Seoul Nat Univ R&Db Foundation

Inventors

• Jang Jyongsik
• Shin Keunyoung

Classifications

• B22F1/107

  containing organic material comprising solvents, e.g. for slip casting · CPC title

• B22F1/068

  Flake-like particles · CPC title

• B22F1/145

  Chemical treatment, e.g. passivation or decarburisation · CPC title

• B22F1/065

  Spherical particles · CPC title

• B22F1/062

  Fibrous particles · CPC title