MODIFIED PEROVSKITE TYPE COMPOSITE OXIDE, METHOD FOR PREPARING THE SAME, AND COMPOSITE DIELECTRIC MATERIAL

• US 20140179826A1
• Filed: 11/15/2013
• Published: 06/26/2014
• Est. Priority Date: 07/18/2008
• Status: Abandoned Application

• Current Assignee: Nippon Chemical Industrial Company Limited
• Original Assignee: Nippon Chemical Industrial Company Limited
• Inventors: Tanabe, Shinji
• Application Number:
  US14/081,558
• Publication Number:
  US 20140179826A1
• Time in Patent Office: Days
• US Class Current: 523/216
• CPC Class Codes: C01B 33/12 Silica; Hydrates thereof, e.g. lepidoic silicic acid
• CPC Class Codes: C01B 33/126 Preparation of silica of undetermined type
• CPC Class Codes: C01G 23/053 Producing by wet processes, e.g. hydrolysing titanium salts
• CPC Class Codes: C01P 2004/84 one phase coated with the other
• CPC Class Codes: C04B 2235/3236 Alkaline earth titanates
• CPC Class Codes: C04B 2235/3248 Zirconates or hafnates, e.g. zircon
• CPC Class Codes: C04B 2235/449 Organic acids, e.g. EDTA, citrate, acetate, oxalate
• CPC Class Codes: C04B 2235/5409 expressed by specific surface values
• CPC Class Codes: C04B 2235/768 Perovskite structure ABO3
• CPC Class Codes: C04B 35/10 based on aluminium oxide
• CPC Class Codes: C04B 35/4682 based on BaTiO3 perovskite phase
• CPC Class Codes: C04B 35/50 based on rare-earth compounds non-oxide rare earth compounds C04B35/5156
• CPC Class Codes: C04B 35/62655 Drying, e.g. freeze-drying, spray-drying, microwave or supercritical drying
• CPC Class Codes: C04B 35/62807 Silica or silicates
• CPC Class Codes: C04B 35/62813 Alumina or aluminates
• CPC Class Codes: C04B 35/62815 Rare earth metal oxides
• CPC Class Codes: C04B 35/62821 Titanium oxide
• CPC Class Codes: C08K 3/10 Metal compounds
• CPC Class Codes: C08K 3/22 of metals
• CPC Class Codes: C08K 3/34 Silicon-containing compounds
• CPC Class Codes: H01B 3/12 : ceramics
• CPC Class Codes: Y10T 428/2991 : Coated
• CPC Class Codes: Y10T 428/2993 : Silicic or refractory material containing [e.g., tungsten oxide, glass, cement, etc.]

Abstract

The invention provides a modified perovskite type composite oxide in which the particle surface of a perovskite type composite oxide is coated with a first component of at least one selected from TiO₂ and SiO₂ and a second component of at least one selected from a group consisting of Al, Zr, Nd, La, Ce, Pr, and Sm, wherein the coating is formed by hydrolyzing at least one selected from a hydrolyzable TiO₂ precursor and a hydrolyzable SiO₂ precursor as a source of the first component and a salt of at least one selected from a group consisting of Al, Zr, Nd, La, Ce, Pr, and Sm as a source of the second component, and then calcining them.

Claims

1. A modified perovskite type composite oxide in which a particle surface of a perovskite type composite oxide is coated with a first component of at least one selected from TiO₂ and SiO₂, and a second component of at least one selected from a group consisting of Al, Zr, Nd, La, Ce, Pr, and Sm,

wherein a coating is formed by hydrolyzing at least one selected from a hydrolyzable TiO₂ precursor and a hydrolyzable SiO₂ precursor as a source of the first component and a salt of at least one selected from a group consisting of Al, Zr, Nd, La, Ce, Pr, and Sm as a source of the second component, and then calcining them.

2. The modified perovskite type composite oxide as set forth in claim 1, wherein the first component is TiO₂ and the second component is at least one selected from a group consisting of Nd, La, Ce, Pr, and Sm.

3. The modified perovskite type composite oxide as set forth in claim 1, wherein the first component is SiO₂ and the second component is at least one selected from a group consisting of Al, Zr, Nd, La, Ce, Pr, and Sm.

4. The modified perovskite type composite oxide as set forth in claim 1, wherein the coating is at a ratio of 0.05% by mass to 20% by mass in terms of oxides with respect to the perovskite type composite oxide.

5. The modified perovskite type composite oxide as set forth in claim 1, wherein the perovskite type composite oxide is of an ABO₃ type, an A-site element is at least one selected from a group consisting of Ba, Ca, Sr, and Mg, and a B-site element is at least one selected from Ti and Zr.

6. The modified perovskite type composite oxide as set forth in claim 1, wherein a BET specific surface area of the perovskite type composite oxide is 0.5 m²/g to 12 m²/g.

9. A composite dielectric material comprising the modified perovskite type composite oxide as set forth in claim 1 and a polymer material.

10. The modified perovskite type composite oxide as set forth in claim 2, wherein the coating is at a ratio of 0.05% by mass to 20% by mass in terms of oxides with respect to the perovskite type composite oxide.

11. The modified perovskite type composite oxide as set forth in claim 3, wherein the coating is at a ratio of 0.05% by mass to 20% by mass in terms of oxides with respect to the perovskite type composite oxide.

12. The modified perovskite type composite oxide as set forth in claim 2, wherein the perovskite type composite oxide is of an ABO₃ type, an A-site element is at least one selected from a group consisting of Ba, Ca, Sr, and Mg, and a B-site element is at least one selected from Ti and Zr.

13. The modified perovskite type composite oxide as set forth in claim 3, wherein the perovskite type composite oxide is of an ABO₃ type, an A-site element is at least one selected from a group consisting of Ba, Ca, Sr, and Mg, and a B-site element is at least one selected from Ti and Zr.

14. The modified perovskite type composite oxide as set forth in claim 4, wherein the perovskite type composite oxide is of an ABO₃ type, an A-site element is at least one selected from a group consisting of Ba, Ca, Sr, and Mg, and a B-site element is at least one selected from Ti and Zr.

15. The modified perovskite type composite oxide as set forth in claim 2, wherein a BET specific surface area of the perovskite type composite oxide is 0.5 m²/g to 12 m²/g.

16. The modified perovskite type composite oxide as set forth in claim 3, wherein a BET specific surface area of the perovskite type composite oxide is 0.5 m²/g to 12 m²/g.

17. The modified perovskite type composite oxide as set forth in claim 4, wherein a BET specific surface area of the perovskite type composite oxide is 0.5 m²/g to 12 m²/g.

18. A composite dielectric material comprising the modified perovskite type composite oxide as set forth in claim 2 and a polymer material.

19. A composite dielectric material comprising the modified perovskite type composite oxide as set forth in claim 3 and a polymer material.

20. A composite dielectric material comprising the modified perovskite type composite oxide as set forth in claim 4 and a polymer material.

7. A method for preparing the modified perovskite type composite oxide, comprising:

(A1) a step of dispersing perovskite type composite oxide particles in a solvent to prepare a slurry;

(A2) a step of adding a source of a first component of at least one selected from a hydrolyzable TiO₂ precursor and a hydrolyzable SiO₂ precursor and a salt of a source of a second component of at least one selected from a group consisting of Al, Zr, Nd, La, Ce, Pr, and Sm to the slurry obtained in (A1), carrying out a hydrolysis reaction of the precursor(s) and the salt in the presence of a catalyst, and then drying the slurry; and

(A3) a step of calcining the dried product obtained in (A2).

8. The method for preparing the modified perovskite type composite oxide as set forth in claim 7, wherein the solvent is a hydrophilic organic solvent and the catalyst is an organic alkali.