Fine barium titanate powder

• US 8,367,206 B2
• Filed: 03/12/2010
• Issued: 02/05/2013
• Est. Priority Date: 03/12/2009
• Status: Active Grant

• Current Assignee: Hanwha Chemical Corporation
• Original Assignee: Hanwha Chemical Corporation
• Inventors: Park, Sei Ung, Ryu, Ju Suk, Lim, Seong Jae, Baek, In Jae
• Primary Examiner(s): KILIMAN, LESZEK B
• Application Number:
  US13/255,554
• Publication Number:
  US 20110318583A1
• Time in Patent Office: 1,061 Days
• Field of Search: 428/402, 428/404, 423/598, 423/608
• US Class Current: 428/402
• CPC Class Codes: C01G 23/003 Titanates C01G23/001 takes precedence
• CPC Class Codes: C01P 2004/03 obtained by SEM
• CPC Class Codes: C01P 2004/62 Submicrometer sized, i.e. from 0.1-1 micrometer
• CPC Class Codes: C01P 2006/12 Surface area
• CPC Class Codes: C04B 2235/3206 Magnesium oxides or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3208 Calcium oxide or oxide-forming salts thereof, e.g. lime
• CPC Class Codes: C04B 2235/3213 Strontium oxides or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3217 Aluminum oxide or oxide forming salts thereof, e.g. bauxite, alpha-alumina
• CPC Class Codes: C04B 2235/3224 Rare earth oxide or oxide forming salts thereof, e.g. scandium oxide
• CPC Class Codes: C04B 2235/3225 Yttrium oxide or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3239 Vanadium oxides, vanadates or oxide forming salts thereof, e.g. magnesium vanadate
• CPC Class Codes: C04B 2235/3241 Chromium oxides, chromates, or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3244 Zirconium oxides, zirconates, hafnium oxides, hafnates, or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3251 Niobium oxides, niobates, tantalum oxides, tantalates, or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3262 Manganese oxides, manganates, rhenium oxides or oxide-forming salts thereof, e.g. MnO
• CPC Class Codes: C04B 2235/3275 Cobalt oxides, cobaltates or cobaltites or oxide forming salts thereof, e.g. bismuth cobaltate, zinc cobaltite
• CPC Class Codes: C04B 2235/42 Non metallic elements added as constituents or additives, e.g. sulfur, phosphor, selenium or tellurium
• CPC Class Codes: C04B 2235/442 Carbonates
• CPC Class Codes: C04B 2235/443 Nitrates or nitrites
• CPC Class Codes: C04B 2235/444 Halide containing anions, e.g. bromide, iodate, chlorite
• CPC Class Codes: C04B 2235/447 : Phosphates or phosphites, e.g. orthophosphate or hypophosphite
• CPC Class Codes: C04B 2235/448 : Sulphates or sulphites
• 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 2235/5445 : submicron sized, i.e. from 0,1 to 1 micron
• CPC Class Codes: C04B 2235/6582 : Hydrogen containing atmosphere
• CPC Class Codes: C04B 2235/765 : Tetragonal symmetry
• CPC Class Codes: C04B 35/4682 : based on BaTiO3 perovskite phase
• CPC Class Codes: H01G 4/1227 : based on alkaline earth titanates
• CPC Class Codes: H01G 4/30 : Stacked capacitors H01G4/33 takes precedence
• CPC Class Codes: Y10T 428/2982 : Particulate matter [e.g., sphere, flake, etc.]
• CPC Class Codes: Y10T 428/2993 : Silicic or refractory material containing [e.g., tungsten oxide, glass, cement, etc.]

Abstract

Provided is barium titanate based powder represented by Chemical Formula 1:
(Ba_xR¹_r1R²_r2)(Ti_yR³_r3R⁴_r4)O₃  [Chemical Formula 1]

• • wherein R¹ is at least one element selected from the group consisting of yttrium (Y) and lanthanoids; R² is at least one element selected from the group consisting of magnesium (Mg), calcium (Ca) and strontium (Sr); R³ includes phosphorus (P) and niobium (Nb); R⁴ is at least one element selected from the group consisting of aluminum (Al), vanadium (V), chrome (Cr), manganese (Mn), cobalt (Co), zirconium (Zr) and tantalum (Ta); r₁ and r₃ independently represent a real number greater than 0 and equal to or less than 0.05; r₂ and r₄ independently represent a real number greater than 0 and equal to or less than 0.1; and (x+r₁+r₂)/(y+r₃+r₄) is a real number ranging from 0.85 to 1.15.

Claims

1. A barium titanate based powder represented by Chemical Formula 1:

(Ba_xR¹_r1R²_r2)(Ti_yR³_r3R⁴_r4)O₃  

 

[Chemical Formula 1]

wherein R¹ is at least one element selected from the group consisting of yttrium (Y) and lanthanoids;

R² is at least one element selected from the group consisting of magnesium (Mg), calcium (Ca) and strontium (Sr);

R³ includes phosphorus (P) and niobium (Nb);

R⁴ is at least one element selected from the group consisting of aluminum (Al), vanadium (V), chrome (Cr), manganese (Mn), cobalt (Co), zirconium (Zr) and tantalum (Ta);

r₁ and r₃ independently represent a real number greater than 0 and equal to or less than 0.05;

r₂ and r₄ independently represent a real number greater than 0 and equal to or less than 0.1; and

(x+r₁+r₂)/(y+r₃+r₄) is a real number ranging from 0.85 to 1.15.

2. The barium titanate based powder according to claim 1, wherein r₁, r₂, r₃ and r₄ independently represent a number greater than 0 and equal to or less than 0.03.

3. The barium titanate based powder according to claim 1, wherein R³ includes niobium and phosphorus at a molar ratio of phosphorus to niobium ranging from 1:

0.1-2.0.

4. The barium titanate based powder according to claim 1, wherein R¹ is yttrium (Y), R² is magnesium (Mg), R³ includes phosphorus (P) and niobium (Nb), and R⁴ includes aluminum (Al), vanadium (V), chrome (Cr) and manganese (Mn).

5. The barium titanate based powder according to claim 1, wherein barium elements contained in the barium titanate based powder are present in an amount of 0.995-1.005 moles per mole of titanium elements.

6. The barium titanate based powder according to claim 1, which comprises a tetragonal phase at a ratio of 60-100 wt % based on the total weight of the barium titanate based powder.

7. The barium titanate based powder according to claim 1, which has a particle size of 10-500 nm and a specific surface area of 2-35 m²/g.

8. The barium titanate based powder according to claim 1, which has a relative dielectric constant of 1500-3000 at 25°

C.

9. The barium titanate based powder according to claim 1, which has a relative dielectric constant, ∈

_T, satisfying Equation 1 at −

55 to 125°

C.;

0.85×

∈

₀≦

∈

_T≦

1.15×

∈

₀(wherein ∈

₀ is a relative dielectric constant at 25°

C.) 

 

[Equation 1].

10. Dielectric materials comprising barium titanate based powder according to claim 1.

11. Ceramic electronic parts comprising barium titanate based powder according to claim 1.