JP2003081636A - Method for producing metal titanate compound having specified shape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a metal titanate compound with a specified shape of the fibrous, flaky, planar, spherical or the like by a simple process with high efficiency. SOLUTION: Titanate with a specified shape is used as the raw material, and bivalent metal titanate compound in which the specified shape of the raw material is almost retained is produced. In this production method, (1) a titanate with a specified shape, (2) one or more kinds of bivalent metal halides, and, if required, (3) one or more kinds of bivalent metal oxides or compounds to form into bivalent metal oxides by heating (hereinafter referred to as bivalent metal oxide or the like) are mixed, and this mixture is subjected to heating reaction, so that the bivalent metal titanate compound expressed by the general formula of nMO.TiO2 (wherein, M is one or more kinds of bivalent metallic elements, and n is the actual number satisfying 0<n<=1) is produced.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention can be used as a filler for paints and resins, as well as cosmetics, pigments, etc., and has high dielectric properties, heat resistance, reinforcement, slidability, ultraviolet shielding properties, etc. The present invention relates to a method for producing a metal titanate compound having a specific shape, which can utilize the performance.

[0002]

PRIOR ART AND PROBLEM TO BE SOLVED BY THE INVENTION General formula nMO.TiO ₂ (where M represents one or more kinds of divalent metal elements, and n represents a real number of 0 <n ≦ 1). The metal titanate compound to be used has properties such as heat resistance, heat insulation, high dielectric property, and ultraviolet shielding property, and is generally known as a material for fine ceramics. As a method for producing a metal titanate compound having shape anisotropy, a fibrous barium titanate is obtained by mixing and firing potassium titanate fiber and barium oxide or a compound that becomes barium oxide by heating. Kaisho 16-1624
No. 03 publication. However, according to this method, a large amount of barium titanate, which is in the form of particles due to the collapse of the shape of the potassium titanate fiber, is formed and becomes a mixture with the fibrous substance, so that a single particle form cannot be obtained.

Further, fibrous titanic acid, a divalent metal oxide or a compound which becomes a divalent metal oxide by heating, and a flux component are mixed and reacted by heating to obtain a fibrous metal titanate. As JP-A-63-2
It is disclosed in Japanese Patent No. 60822. Further, the fibrous titanic acid is obtained by mixing the fibrous alkali titanate, a divalent metal oxide, a compound that becomes a divalent metal oxide by heating or a halide of the metal, and a flux component, and reacting by heating. It is disclosed in JP-A-2-164800 that a metal salt can be obtained.

However, in these methods, only fibrous substances are obtained as products, and plate-like, scale-like,
No spherical shape was obtained. Further, since a flux component is used in addition to the raw material, there is a drawback that the yield of the product relative to the charged raw material is low and the production efficiency is poor.
Further, fibrous materials are excellent in mechanical strength reinforcement, etc., but plate-like and scale-like materials are suitable for high dielectric properties, UV shielding properties, etc. For example, a spherical shape is suitable, and a filler of each shape is required.

The objects of the present invention are fibrous, scale-like, plate-like,
It is an object of the present invention to provide a method for producing a metal titanate compound capable of producing a divalent metal titanate compound having a specific shape such as a sphere in a simple process and with high efficiency.

[0006]

The present invention is a method for producing a titanate compound of a divalent metal in which a titanate having a specific shape is used as a raw material and the specific shape of the raw material is substantially maintained. ) Titanate having a specific shape, and (2)
One or more kinds of divalent metal halides and, if necessary, (3) one or more kinds of divalent metal oxides or compounds that become divalent metal oxides by heating (hereinafter, these metal oxides and The compound is mixed with “a divalent metal oxide or the like”, and the mixture is heated and reacted to give a compound of the general formula nMO · TiO ₂ (where M is one or more divalent metal elements). , N is a real number satisfying 0 <n ≦ 1), and is characterized by producing a divalent metal titanate compound.

According to the present invention, fibrous, scale-like, plate-like,
Using a titanate having a specific shape such as a sphere as a raw material, the metal ion in this titanate is replaced with a desired divalent metal ion, and at the same time, the crystal structure is converted to change the specific shape of the raw material titanate. A titanic acid compound of a divalent metal that is substantially maintained can be produced with high efficiency.

As the titanate (1) used in the present invention, conventionally known alkali titanate or the like can be widely used. Specific examples of fibrous materials include K ₂ O.
Potassium titanate metal salts and hydrates of 4TiO ₂ , K ₂ O · 6TiO ₂ , K ₂ O · 8TiO _2, etc., Na ₂ O · Ti
O _2, such as _{Na 2 O · 3TiO 2, Na} 2 O · 5TiO 2 titanate sodium metal salt and hydrate and the like.
Further, specific examples of the spherical substance include potassium titanate metal salts such as K ₂ O · 2TiO ₂ and hydrates. Specific examples of the platelet, the general formula _{A x B y □ z Ti 2-} (y + z) O 4
(Here, A and B are mutually different trivalent metals, □
Indicates a defect site of Ti. x represents a positive real number satisfying 0 <x <1.0, and y and z represent 0 or a positive real number satisfying 0 <y + z <1.0. ) Plate-like titanates represented by Specific examples of the plate-like titanate include K _0.80 Li _0.266 Ti _1.733 O ₄ and K _0.80 Mg _{0.40.
Ti 1.6 0 O 4, K 0.575} Fe 0.575 Ti 1.425 O 4, Cs 0.7
Ti _1.825 □ _0.175 O _{4 and the} like can be mentioned. These compounds are easily produced by various known methods, for example, a sintering method, a flux method, a melt method, a metal alkoxide method, etc., but in order to impart various specific shapes, they are produced by the flux method. Those used are preferably used.

The divalent metal halide (2) used in the present invention includes Ba, Ca, Sr, Mg, Zn,
Examples thereof include chloride, bromide and iodide of one or more metals selected from the group consisting of Pb, Co, Ni and the like. Among these, chloride is particularly preferably used from the viewpoint of easy availability.

Examples of the divalent metal oxide and the like (3) used in the present invention include a divalent metal oxide and a compound which becomes a divalent metal oxide by heating. Examples of the divalent metal oxide include Ba, Ca, Mg, Sr, Zn and P.
Examples include oxides of one or more divalent metals selected from the group consisting of b, Co, Ni and the like. Examples of the compound that becomes a divalent metal oxide by heating include Ba, Ca, Mg, and S.
Inorganic acid salts such as hydroxides, carbonates, nitrates and phosphates of one or more divalent metals selected from the group consisting of r, Zn, Pb, Co and Ni, acetates, oxalates, stearines. Examples thereof include carboxylic acid salts such as acid salts, metal alcoholates, organic compounds such as metal acetyl alcoholates, which are converted into metal oxides at the heating temperature during the production of the metal titanate compound. In the present invention, the divalent metal oxide or the like (3) is a component added as necessary and is an optional component.

Among the above divalent metal halides (2) and divalent metal oxides (3), there are compounds having water of crystallization, but such compounds are in the form as they are. Since it may cause troubles in work, it is preferable to use it in a dry state.

The mixing ratio of the respective raw materials of (1), (2) and (3) is such that the divalent metal halide (2) and the divalent metal oxide with respect to titanium in the titanate (1). The ratio R1 of the divalent metal element in (3) is 0.25 ≦ R1.
<5, and the ratio R2 of the divalent metal element in the divalent metal oxide (3) to the divalent metal element in the divalent metal halide (2) is 0 ≦ R2 <2.5. It is preferable to mix them as described above. By setting the mixing ratio within such a range, the metal titanate compound can be obtained in a high yield. The above ratios R1 and R2 are ratios represented by the following formulas.

R1 = (divalent metal in divalent metal halide (2) and divalent metal oxide (3)) / (Ti in titanate) R2 = (divalent metal oxide Etc. (divalent metal in (3)) /
(Divalent Metal in Divalent Metal Halide (2)) The method for mixing the above raw materials (1), (2) and (3) is
It is not particularly limited, and a method of mixing using an ordinary mixer can be applied. The mixing method is not limited to dry mixing, and may be a method of drying the dried product after wet mixing, or a method of further granulating and drying the wet mixture by spray drying or the like. Good.

In the present invention, the mixture is heated and reacted to produce a metal titanate compound. The reaction temperature is usually preferably about 600 ° C to 1100 ° C, more preferably about 700 ° C to 1000 ° C. Reaction time is 10
Minutes to 12 hours are preferable, and more preferably 1 hour to 10 hours.

In the present invention, after completion of the above reaction, the reaction product is treated with hot water or cold water to remove water-soluble components such as flux. If necessary, this may be washed with an acid or an alkali, and then crushed, dried and classified to recover the desired metal titanate compound. The above-mentioned crushing can be carried out using a general crusher, and the classification is preferably carried out by various known classification methods such as air classification.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited to the following Examples, and may be appropriately modified within the scope of the gist of the present invention. It can be implemented.

Example 1 Potassium titanate (K ₂ O.4Ti) having an average fiber length of 20 μm and an average fiber diameter of 0.4 μm
O ₂ ) fiber 10 g, calcium hydroxide (manufactured by Wako Pure Chemical Industries,
Reagent special grade, Ca (OH) ₂ ) 4.3 g, calcium chloride (Wako Pure Chemical Industries Ltd., reagent special grade, CaCl ₂ ) 4.3 g were homogeneously mixed in a mortar (R1 = 1, R2 = 1.56) 1
0 g was packed in a cylindrical mold with a diameter of 25 mm, and pressure-molded was transferred to a mullite crucible and placed in a muffle furnace for 950
After firing at 0 ° C. for 4 hours, wet defibration and washing in 0.1N nitric acid were taken out by filtration and dried for 3 hours in a constant temperature dryer at 110 ° C.

The product obtained was 6.1 g, and the result of X-ray diffraction was only perovskite-type calcium titanate. As a result of observing this sample with an electron microscope (SEM), an average fiber length of 17 μm and an average fiber length of 17 μm were obtained. It was a fibrous material having a diameter of 0.5 μm.

Example 2 Potassium titanate (K ₂ O.4Ti) having an average fiber length of 20 μm and an average fiber diameter of 0.4 μm
O ₂ ) fiber 10 g, barium chloride (manufactured by Wako Pure Chemical Industries, special grade reagent, BaCl ₂ ) 16.7 g homogeneously mixed in a mortar (R1 = 0.83, R2 = 0) 10 g diameter 25 mm
Filled in a cylindrical mold of No. 1 and pressure-molded was transferred to a mullite crucible and baked in a muffle furnace at 900 ° C. for 3 hours,
Wet defibration and washing in 0.1N nitric acid are filtered off,
It was dried for 3 hours in a constant temperature dryer at 110 ° C.

The product obtained was 4 g, and the result of X-ray diffraction was barium tetratitanate only. As a result of observing this sample with an electron microscope (SEM), an average fiber length of 17
It was a fibrous material having a particle diameter of μm and an average fiber diameter of 0.5 μm.

Example 3 Potassium titanate having an average fiber length of 17 μm and an average fiber diameter of 0.4 μm (T, manufactured by Otsuka Chemical Co., Ltd.)
10 g of ISMO-D) fiber, 5.2 g of barium carbonate (manufactured by Wako Pure Chemical Industries, Ltd., reagent grade, BaCO ₃ ) 5.2 g, and barium chloride (16.5 g of Wako Pure Chemical Industries Ltd, reagent grade, BaCl ₂ ) were homogeneously mixed in a mortar. (R1 = 0.97, R2 = 0.
33) 10 g of a cylindrical mold having a diameter of 25 mm was filled and pressure-molded, transferred to a mullite crucible, baked in a muffle furnace at 1000 ° C. for 3 hours, then wet defibrated and washed in 0.1 N nitric acid. The obtained product was separated by filtration and dried in a constant temperature dryer at 110 ° C. for 3 hours.

The amount of the obtained product was 7.2 g, and the X-ray diffraction result was in agreement with the perovskite type barium titanate. As a result of observing this sample with an electron microscope (SEM), it was a fibrous material having an average fiber length of 16 μm and an average fiber diameter of 0.4 μm.

Example 4 Potassium titanate (K ₂ O.4Ti) having an average fiber length of 20 μm and an average fiber diameter of 0.4 μm
O ₂ ) fiber 10 g, barium carbonate (manufactured by Wako Pure Chemical Industries, Ltd., reagent grade, BaCO ₃ ) 9.5 g, strontium carbonate (manufactured by Wako Pure Chemical Industries, reagent grade, SrCO ₃ ) 2.9 g, strontium chloride (Wako Pure Chem. (Reagent special grade, SrCl ₂ )
A homogeneous mixture of 4.6 g in a mortar (R1 = 1, R2 =
2.3) 10 g of a cylindrical mold having a diameter of 25 mm was filled and pressure-molded, transferred to a mullite crucible, baked in a muffle furnace at 1000 ° C. for 3 hours, and then wet defibrated in 0.1 N nitric acid. The washed product was separated by filtration and dried in a constant temperature dryer at 110 ° C. for 3 hours.

The amount of the obtained product was 7.5 g, and the result of X-ray diffraction was consistent with that of perovskite type barium strontium titanate (Ba _0.5 Sr _0.5 TiO ₂ ).
As a result of observing this sample with an electron microscope (SEM),
It was a fibrous material having an average fiber length of 17 μm and an average fiber diameter of 0.5 μm.

Example 5 Sodium trititanate (manufactured by Otsuka Chemical Co., average fiber length 19 μm, average fiber diameter 5 μm) 1
0 g, basic magnesium carbonate (Wako Pure Chemical Industries, Ltd., 3 Mg
CO ₃ .Mg (OH) ₂ .3H ₂ O) 4.7 g, magnesium chloride (manufactured by Wako Pure Chemical Industries, special grade reagent, MgCl ₂ ) 4.7
g homogeneously mixed in a mortar (R1 = 1, R2 = 1) 1
0 g was filled in a cylindrical mold having a diameter of 25 mm, and pressure-molded was transferred to a mullite crucible, and 900 m in a muffle furnace.
After firing at 0 ° C for 3 hours, wet defibration and washing in 0.1N nitric acid were taken out by filtration and dried for 3 hours in a constant temperature dryer at 110 ° C.

The amount of the product obtained was 5 g, and the result of X-ray diffraction was consistent with that of perovskite-type magnesium titanate. As a result of observing this sample with an electron microscope (SEM), an average fiber length of 15 μm and an average fiber diameter of 4 μm were obtained. It was a columnar object.

(Example 6) 5 g of lithium potassium titanate (K _0.80 Li _0.266 Ti _1.733 O ₄ , average particle size 9 μm, average particle thickness 0.8 μm), calcium hydroxide (manufactured by Wako Pure Chemical Industries, special grade reagent, Ca) (OH) ₂ ) 3.2 g, calcium chloride (manufactured by Wako Pure Chemical Industries, special grade reagent, CaCl ₂ ) 5 g
Homogenously mixed in a mortar (R1 = 1.8, R2 = 1)
10 g of a cylindrical metal mold with a diameter of 25 mm was filled, and pressure-molded was transferred to a mullite crucible and placed in a muffle furnace for 10
After calcination at 00 ° C for 3 hours, wet defibration in 0.2N nitric acid,
The washed product was separated by filtration and dried in a constant temperature dryer at 110 ° C. for 3 hours.

The product obtained was 5 g, and the result of X-ray diffraction was only perovskite-type calcium titanate. As a result of observing this sample with an electron microscope (SEM), an average particle size of 10 μm and an average particle thickness of 1 It was a plate-like material having a size of 1 μm.

(Example 7) 5 g of magnesium potassium titanate (K _0.80 Mg _0.40 Ti _1.60 O ₄ , average particle diameter 4 μm, average particle thickness 1 μm), strontium hydroxide (manufactured by Wako Pure Chemical Industries, special grade reagent, Sr (OH) ) ₂ ) 2.7 g, strontium chloride (manufactured by Wako Pure Chemical Industries, special grade reagent, SrCl ₂ ).
A homogeneous mixture of 5.2 g in a mortar (R1 = 1.16,
(R2 = 0.68) 10 g was packed in a cylindrical mold having a diameter of 25 mm, pressure-molded, transferred to a mullite crucible, baked in a muffle furnace at 1000 ° C. for 3 hours, and then wet in 0.2 N nitric acid. The defibrated and washed product was separated by filtration and dried in a constant temperature dryer at 110 ° C. for 3 hours.

The obtained product was 5.7 g, and the result of X-ray diffraction was in agreement with the perovskite type strontium titanate. As a result of observing this sample with an electron microscope (SEM), the average particle size was 5 μm and the average particle size was 5 μm. It was a plate having a thickness of 1.3 μm.

(Embodiment 8) 10 g of nearly spherical potassium titanate (K ₂ O.2TiO ₂ , average particle size 20 μm), calcium hydroxide (manufactured by Wako Pure Chemical Industries, special grade reagent, Ca (O)
H) ₂ ) 2.8 g and calcium chloride (Wako Pure Chemical Industries, Ltd. special grade reagent, CaCl ₂ ) 4.2 g homogeneously mixed in a mortar (R1 = 0.94, R2 = 1) 10 g cylinder with a diameter of 25 mm The mold was filled and pressure-molded, then transferred to a mullite crucible and baked in a muffle furnace at 900 ° C for 3 hours.
Wet defibration and washing in 0.3N nitric acid are filtered off,
It was dried for 3 hours in a constant temperature dryer at 110 ° C.

The product obtained was 5.3 g, and the result of X-ray diffraction was only perovskite-type calcium titanate. As a result of observing this sample with an electron microscope (SEM), spherical particles having an average particle size of 17 μm were obtained. Met.

[0033]

According to the present invention, a divalent metal titanate compound having a specific shape such as fibrous, scale-like, plate-like or spherical shape can be produced by a simple production process. Therefore,
According to the present invention, the process control is easy and the yield of the target product with respect to the charged raw materials is high. Therefore, the production method of the present invention is an industrially advantageous production method as a method for producing a metal titanate compound having a specific shape.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Harue Matsunaga             463 Kagasuno, Kawauchi Town, Tokushima City, Tokushima Prefecture             Tokushima Research Institute F-term (reference) 4G047 CA06 CB04 CC01 CC02 CC03                       CD05

Claims (4)

[Claims] 1. A method for producing a titanate compound of a divalent metal in which a titanate having a specific shape is used as a raw material, and the specific shape of the raw material is substantially maintained, (1) Titanium having the specific shape An acid salt, and (2) one or more divalent metal halides, and optionally (3)
One or more kinds of divalent metal oxides or compounds that become divalent metal oxides by heating (hereinafter, "divalent metal oxides and the like")
, And the mixture is heated and reacted to produce nMO.TiO ₂ (where M represents one or more divalent metal elements, and n is a real number satisfying 0 <n ≦ 1). .)
A method for producing a metal titanate compound having a specific shape, which comprises producing a divalent metal titanate compound represented by: 2. The ratio R1 of the divalent metal element in the divalent metal halide (2) and the divalent metal oxide (3) to titanium in the titanate (1) is 0.25 ≦. R1
<5, and the ratio R2 of the divalent metal element in the divalent metal oxide or the like (3) to the divalent metal element in the divalent metal halide (2) is 0 ≦ R2 <2.5. So that
The method for producing a metal titanate compound having a specific shape according to claim 1, wherein the raw materials of (1), (2) and (3) are mixed. 3. The specific shape according to claim 1 or 2, wherein the compound which becomes a divalent metal oxide by heating is a divalent metal hydroxide or a divalent metal carbonate. A method for producing a metal titanate compound having the same. 4. Titanate (1) is a fibrous K ₂ O.4
TiO ₂ or the general formula _{A x B y □ z Ti 2-} (y + z) O 4 ( where,, A and B are mutually different monovalent to trivalent metal, □ the Ti
The defect site of is shown. x represents a positive real number satisfying 0 <x <1.0, and y and z represent 0 or a positive real number satisfying 0 <y + z <1.0. 4. The method for producing a metal titanate compound having a specific shape according to any one of claims 1 to 3, which is a plate titanate represented by the formula (4).