JPH05310410A - Production of strontium hydroxyapatite powder - Google Patents

Abstract

PURPOSE:To simply obtain a strontium hydroxyapatite powder in a short time by compounding strontium hydrogen phosphate and strontium hydroxide or strontium carbonate with water in a prescribed ratio, stirring the mixture in a pot mill, drying the obtained slurry, and subsequently calcining the dried powder. CONSTITUTION:Strontium hydrogen phosphate and strontium hydroxide or strontium carbonate are weighted, mixed with a proper amount of water and subsequently stirred in a pot mill at room temperature. The obtained slurry is dried to obtain the powder of the strontium apatite precursor, which is calcined. The strontium hydrogen phosphate and the strontium hydroxide or strontium carbonate are compounded in a molar ratio of approximately 2:1 to about 1:1. The stirring time in the pot mill is preferably >=1hr, and the calcination temperature is preferably 600-1200 deg.C.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing strontium hydroxyapatite powder. Hydroxyapatite has properties such as biocompatibility, ion exchange characteristics and surface adsorption characteristics, and is an artificial tooth root, artificial bone, humidity sensor, alcohol sensor, heavy metal and phosphorus removal wastewater treatment material, polymer column packing material. It is expected to be put to practical use in various fields. Calcium hydroxyapatite is mainly widely known as hydroxyapatite, but strontium hydroxyapatite is also practically used as a packing material for chromatography and is a substance useful as an industrial material.

[0002]

2. Description of the Related Art Methods for producing strontium hydroxyapatite powder include a dry method, a solution method and a hydrothermal method. The dry method is a method in which strontium diphosphate and strontium carbonate are mixed and heated under reduced pressure at 1100 ° C. for 16 hours and further heated in a steam atmosphere at 900 ° C. for 21 hours, or ammonium dihydrogen phosphate and strontium carbonate are mixed. A method of heating at 900 ° C. after mixing and molding is known.
In addition, the solution method is to add ethylenediamine to the strontium nitrate aqueous solution kept at 95 ° C, add ammonium dihydrogenphosphate aqueous solution to which ethylenediamine is added and keep at 95 ° C, and let it stand at 95 ° C for a whole day and night. A method of drying, heating at 950 ° C. for 4 hours is known. The hydrothermal method is a method in which ammonium dihydrogen phosphate is mixed with strontium carbonate and subjected to hydrothermal treatment (300 ° C., 5 days) in an autoclave together with water.

The dry method is liable to produce by-products and requires repeated heating in order to complete the reaction. For this reason, heating may be required for several tens of hours to several days. on the other hand,
Since the production of phosphate in a solution is greatly affected by pH, the solution method requires strict pH adjustment. The solution method requires a long aging operation. Further, in the hydrothermal method, it is necessary to perform heat treatment for a long time.

Therefore, it is expected to develop a technique for easily producing strontium hydroxyapatite powder.

[0005]

The problem to be solved is to provide a novel manufacturing technique capable of synthesizing strontium hydroxyapatite powder in a relatively short time without requiring complicated procedures such as pH adjustment. ..

[0006]

The technique for producing strontium hydroxyapatite compound ceramics according to the present invention is
It is as follows. In this specification, the term "strontium hydroxide apatite compound" means Sr ₁₀ (PO ₄ ) ₆ X ₂ (X) formed as a result of the reaction of strontium hydrogen phosphate or strontium hydroxide or strontium carbonate at a required ratio. = OH and the like) is meant.

Strontium hydrogen phosphate and strontium hydroxide or strontium carbonate in a molar ratio of 1: 1
Weigh in a ratio of ˜2: 1, add more than 10% by weight of water and stir in a pot mill at room temperature for several hours. By using a powder insoluble or hardly soluble in water as a starting material and applying a mechanical force in the presence of water in a pot mill, a so-called mechanochemical reaction occurs and a precursor of strontium apatite is obtained. Stirring for several hours using a stirrer instead of a pot mill leaves the starting material as unreacted material. Therefore, in order to complete the reaction, it is necessary to stir in a temperature range higher than room temperature or for a longer time. Therefore, it is desirable to stir the starting material in a pot mill. Further, if the stirring time is lengthened, the average particle size of the powder becomes smaller.
Therefore, the stirring time is preferably 16 hours or more.

When the obtained slurry of the strontium apatite precursor is dried and then heated, it is first dehydrated gradually, and crystalline strontium hydroxyapatite powder is obtained in a temperature range of 500 ° C. or higher. When the calcination temperature is 600 ° C. or higher, the crystallinity of the powder is improved, but when the calcination temperature is higher than 800 ° C., the average particle size of the powder is large. Therefore, it is desirable to set the calcination temperature to 800 ° C. in order to obtain fine powder.

[0009]

【Example】

Example 1 Strontium hydrogen phosphate and strontium hydroxide were weighed at a molar ratio of 2: 1 and water was added so that the weight ratio was 10% or more, and 500 g of zirconia balls and 500 g of zirconia balls were used at room temperature every time. Stir at 50 rpm. After stirring, the powder obtained by drying is calcined at 800 ° C.

The powder thus obtained has an average particle size of about 1 μm.
m indicates a substantially spherical shape. According to the X-ray diffraction spectrum of the product, only strontium hydroxyapatite is produced.

Example 2 Strontium hydrogen phosphate and strontium hydroxide were weighed at a molar ratio of 2: 1, water was added so that the weight ratio was 10% or more, and the mixture was stirred with a stirrer at room temperature. After stirring, the powder obtained by drying is calcined at 800 ° C.

The powder thus obtained has an average particle size of about 1 μm.
m indicates a substantially spherical shape. According to the X-ray diffraction spectrum of the product, mainly tristrontium phosphate (Sr ₃ (PO ₄ ) ₂ ) is obtained.

Example 3 Strontium hydrogen phosphate and strontium hydroxide were weighed out in a molar ratio of 3: 2, water was added so that the weight ratio was 10% or more, and 500 g of zirconia balls were placed in a zirconia pot mill at room temperature. Stir below at 50 rpm. After stirring, the powder obtained by drying is calcined at 800 ° C.

The powder thus obtained has an average particle size of about 1 μm.
m indicates a substantially spherical shape. According to the X-ray diffraction spectrum of the product, only strontium hydroxyapatite is produced.

[0015]

As described above, the technique for producing the strontium hydroxyapatite compound ceramics according to the present invention is that the starting materials are stirred in a pot mill for several hours or more and then calcined. Apatite powder can be synthesized. In the present invention, a substance that is sparingly soluble or insoluble in water is selected as the starting material, so that strict adjustment of pH is not particularly required as described at the beginning.
When the mixture is stirred in a pot mill, a strontium apatite precursor is rapidly produced, and by calcining it, crystalline strontium hydroxyapatite is produced. Therefore, it is not necessary to repeat heating in order to obtain a strontium hydroxyapatite single phase as in the dry method. By the above operation, fine powder having an average particle size of about 1 μm can be obtained. Further, according to the present invention, the heating time can be shortened as compared with other methods, so that the running cost can be reduced in the production of products.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Takahiro Suzuki 3-11-3 Kitahara-cho, Mizuho-ku, Nagoya-shi, Aichi 102, Mizuho Kitahara 102 (72) Inventor Kaori Nishizawa 3-90, Koen-cho, Nishi-ku, Aichi Sun Heights Maeda A-206 (72) Inventor Hajime Nagae 1-70, Heiwagaoka, Meito-ku, Nagoya, Aichi Prefecture 9 Inoishi stone houses, No. 402

Claims (4)

[Claims] 1. Strontium hydrogen phosphate and strontium hydroxide or strontium carbonate are weighed, water is added in an appropriate amount, and the mixture is stirred in a pot mill at room temperature. The obtained slurry is dried to obtain a strontium apatite precursor powder. A method for producing a strontium hydroxyapatite compound ceramics, which is characterized in that crystalline strontium hydroxyapatite is obtained by further calcination. 2. Strontium hydrogen phosphate and strontium hydroxide or strontium carbonate are weighed,
The production method according to the first aspect, wherein the molar ratio is 2: 1 to 1: 1. 3. Stir in a pot mill for a stirring time of
The method according to item 1, which is for 1 hour or more. 4. The manufacturing method according to claim 1, wherein the calcination temperature is 600 to 1200 ° C.