JPH06256006A - Production of nitride powder - Google Patents
Production of nitride powderInfo
- Publication number
- JPH06256006A JPH06256006A JP6146593A JP6146593A JPH06256006A JP H06256006 A JPH06256006 A JP H06256006A JP 6146593 A JP6146593 A JP 6146593A JP 6146593 A JP6146593 A JP 6146593A JP H06256006 A JPH06256006 A JP H06256006A
- Authority
- JP
- Japan
- Prior art keywords
- powder
- raw material
- nitride
- metal
- iron
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B21/00—Nitrogen; Compounds thereof
- C01B21/06—Binary compounds of nitrogen with metals, with silicon, or with boron, or with carbon, i.e. nitrides; Compounds of nitrogen with more than one metal, silicon or boron
Abstract
Description
【産業上の利用分野】本発明は、窒化物粉体の製造方法
に関し、より詳細には窒化物ファインセラミックス原料
粉体や磁性トナー用原料粉体、磁気記録材料用原料粉体
に好適な窒化物粉体の製造方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a nitride powder, and more particularly to a nitride powder suitable for a nitride fine ceramics raw material powder, a magnetic toner raw material powder, and a magnetic recording material raw material powder. The present invention relates to a method for producing powder.
【従来の技術】従来より、ファインセラミックスや磁性
トナー、磁気記録材料等の原料として、金属や金属酸化
物、金属塩化物等の粉体に窒化処理を施した金属窒化物
粉体が用いられている。この金属窒化物を製造する方法
として、種々の方法が提案、実施されており、例えば、
窒化鉄粉体については、窒化性雰囲気において、プラズ
マアーク中に鉄の粉末を供給する方法や、プラズマアー
クにより鉄を蒸発させて鉄蒸気とし、これに窒素ガスを
供給することにより、粒径０．０１μｍ程度の窒化鉄の
超微粒子を製造している。また、金属蒸気や金属塩化物
等の蒸気を、アンモニアガスと還元性のガス雰囲気中で
反応させて金属窒化物の微粉末を製造する方法も採られ
ている。更に、ロータリキルン等の焼成装置を用いて、
高温窒化性雰囲気中に原料粉体を導入し、原料粉体の窒
化物を製造する方法も一般的である。2. Description of the Related Art Conventionally, metal nitride powder obtained by nitriding powder of metal, metal oxide, metal chloride, etc. has been used as a raw material for fine ceramics, magnetic toner, magnetic recording materials and the like. There is. As a method for producing this metal nitride, various methods have been proposed and carried out, for example,
Regarding the iron nitride powder, in a nitriding atmosphere, iron powder is supplied into the plasma arc, or iron is vaporized by the plasma arc to form iron vapor, and nitrogen gas is supplied to this to obtain a particle size of 0. Ultrafine iron nitride particles of about 0.01 μm are manufactured. Further, a method of producing fine powder of metal nitride by reacting vapor of metal vapor or metal chloride with ammonia gas in a reducing gas atmosphere is also adopted. Furthermore, using a firing device such as a rotary kiln,
A method of producing a nitride of the raw material powder by introducing the raw material powder into a high temperature nitriding atmosphere is also common.
【発明が解決しようとする課題】これらの窒化物粉体
は、最終製品の性能の点では、一般的にその粒径が小さ
い程好ましいとされているが、粒径が小さくなりすぎる
とその加工性において種々の困難な問題が生じる。すな
わち磁性トナーでは、磁性体粒子を樹脂などで被覆ある
いは樹脂と混練する必要があるが、このとき粒子が小さ
すぎると磁性体粒子の体積充填率が下がり、被覆材を含
めた全体としての磁化の値が小さくなったり、凝集によ
り製品に不均一性が発生する。このように、窒化物粉体
は、その用途に応じた好ましい粒径範囲があり、ファイ
ンセラミックス原料としては、平均粒径が０．２〜１０
μｍ程度、磁性トナーとしては数μｍ以下、また磁気記
録材料としては０．５〜数μｍ程度であることが望まし
く、概ね平均粒径が１μｍ程度であれば、これらの用途
に共通して、しかも好適なものとして使用することがで
きる。しかし、前記の方法では、粒径１μｍ程度の窒化
物の微粉末を、効率良く、しかも安価に得ることは困難
であった。例えばプラズマ法によれば、粒径が０．０１
μｍという超微粉末を得ることができるものの、逆に１
μｍ程度の粒径のものを多量に得ることが難しく、ま
た、金属や金属塩化物の蒸気を窒化する方法では、生成
窒化物が数珠状の連続体となり、単粒子が得られないと
いう問題を抱えていた。これら生成窒化物の生産性や形
状の問題に加えて、プラズマを発生させたり、原料を一
度蒸発させたりする必要があるため、大量の電力または
熱エネルギーを必要とし、製造装置が高価になるととも
に、反応条件の制御等の製造プロセスも複雑になり、結
果的に製造コストが上昇し、製品として非常に高価なも
のになっていた。一方、ロータリキルン等の焼成装置を
用いて窒化物粉体を製造する方法では、安価に、しかも
多量に窒化物を製造することができるが、処理できる原
料粉体の粒径に制限があり、通常粒径が数μｍ〜数十μ
ｍ程度の粗粒粉末は処理することができるが、粒径１μ
ｍ程度の粉体を処理しようとすると、粉体は、その表面
エネルギーが大きいために、反応中にキルン内壁面に付
着したり、粒子同士が焼結を起こして大きな粒塊となっ
てしまう。この焼結体となった粒塊は硬度が高いため
に、１μｍ程度の粒径まで粉砕するには非常に長い時間
と大きな機械的エネルギーを要し、必ずしも実用的では
なかった。すなわち従来の方法では、ファインセラミッ
クスや磁性トナー、磁気記録材料等の原料として好適な
粒径１μｍ程度の窒化物の微粉末を、安価に、しかも効
率良く得ることは困難であった。従って、本発明の目的
は、粒径１μｍ程度の微細な窒化物粉体を、多量にか
つ、窒化処理後に粉砕等の後処理を必要せずに効率良
く、しかも安価に製造することにある。In view of the performance of the final product, it is generally said that the smaller the particle size of these nitride powders, the more preferable it is. A variety of difficult problems arise in sex. That is, in the magnetic toner, it is necessary to coat or knead the magnetic particles with a resin or the like, but if the particles are too small at this time, the volume filling rate of the magnetic particles decreases and the magnetic properties of the entire magnet including the coating material are reduced. The product becomes inhomogeneous due to the small value or aggregation. As described above, the nitride powder has a preferable particle size range according to its use, and as a fine ceramic raw material, the average particle size is 0.2 to 10
It is preferable that the magnetic toner has a particle size of about 1 μm, a magnetic toner of several μm or less, and a magnetic recording material of about 0.5 μm to several μm. It can be used as a suitable one. However, according to the above method, it has been difficult to efficiently obtain a fine powder of nitride having a particle size of about 1 μm at a low cost. For example, according to the plasma method, the particle size is 0.01
Ultra fine powder of μm can be obtained, but conversely 1
It is difficult to obtain a large amount of particles having a particle size of about μm, and in the method of nitriding vapor of metal or metal chloride, the generated nitride becomes a bead-shaped continuous body, and a single particle cannot be obtained. I was holding. In addition to the problems of productivity and shape of these generated nitrides, it is necessary to generate plasma or vaporize the raw material once, which requires a large amount of electric power or thermal energy, and the manufacturing equipment becomes expensive. The production process such as control of reaction conditions is complicated, resulting in an increase in production cost and a very expensive product. On the other hand, in the method of producing a nitride powder using a firing device such as a rotary kiln, it is possible to inexpensively produce a large amount of nitride, but there is a limit to the particle size of the raw material powder that can be processed, Normal particle size is several μm to several tens of μ
Coarse-grained powder of about m can be processed, but particle size is 1μ
When a powder having a size of about m is treated, the powder has a large surface energy, so that the powder adheres to the inner wall surface of the kiln during the reaction or particles are sintered with each other to become a large agglomerate. Since the agglomerates formed into this sintered body have high hardness, it takes a very long time and a large amount of mechanical energy to pulverize to a particle size of about 1 μm, which is not always practical. That is, according to the conventional method, it has been difficult to inexpensively and efficiently obtain fine powder of a nitride having a particle diameter of about 1 μm, which is suitable as a raw material for fine ceramics, magnetic toners, magnetic recording materials and the like. Therefore, an object of the present invention is to manufacture a large amount of fine nitride powder having a particle size of about 1 μm, efficiently and inexpensively without requiring post-treatment such as crushing after nitriding treatment.
【課題を解決するための手段及び作用】本発明者らは、
金属窒化物粉体の製造に関する上記課題を解決すべく鋭
意研究の結果、安価な製造方法である焼成装置を用いた
方法を採用し、窒化反応において強制的に焼結を解くこ
とにより、所望の粒径１μｍ程度の微細な窒化物粉体を
多量にかつ効率良く、しかも安価に得ることができる方
法を見出し、本発明を完成するに至った。すなわち回転
式加熱炉内に、原料粉体とともに粉砕媒体を導入し、回
転により両者を強く攪拌しながら高温の窒化性雰囲気に
おいて、窒化反応を起こさせると同時に解砕並びに粉砕
を行うことにより、粉体粒子同志が焼結しない金属窒化
物を得ることができる。本発明に係る窒化物粉体の製造
に用いられる原料粉体は、金属や合金、金属間化合物、
さらにそれらの酸化物や塩化物等の金属化合物からな
り、直径が０．０５〜１０μｍ、好ましくは０．１〜１
μｍの粉体である。また、金属の種類は、特に制限され
るものではなく、通常の磁性材料として使用される金属
や合金、あるいは金属間化合物例えば、鉄やコバルト、
ニッケル、マンガン、クロム等の金属や合金、あるいは
それらを含む金属間化合物の他にも、アルミニウムやチ
タン、シリコンおよびネオジウム、サマリウム等の希土
類金属等種々の金属や合金、あるいはそれらを含む金属
間化合物を挙げることができる。これら原料粉体ととも
に回転式加熱炉に導入される粉砕媒体としては、原料粉
体に汚染の影響を与えず、かつ熱的、機械的強度に優れ
た物質から形成されていることが好ましく、例えば、原
料粉体が鉄の場合には、純鉄または鉄合金からなる粉砕
媒体を、またアルミニウムの場合には、酸化アルミニウ
ムや窒化アルミニウム、ほう化アルミニウム等のセラミ
ックスに変換して、その機械的強度が増強された形態で
使用される。また、その形状は、特に制限されるもので
はないが、直径０．２〜３０ｍｍ、好ましくは０．５〜
１０ｍｍの小球を、単独または直径の異なる小球を適宜
組み合わせて使用することができる。また、球状に限ら
ず、同様の大きさを有する棒状でも構わない。更に、球
状と棒状のものを組み合わせて使用してもよい。例え
ば、原料粉体が鉄の場合には、直径数ｍｍの鉄球を単独
に、あるいは直径の異なる２種類以上の鉄球を組み合わ
せて、また鉄球に鉄棒を組み合わせて使用することがで
きる。このように、粉砕媒体は、原料粉体の種類や粒
径、また生成窒化物の目的とされる形状に応じて適宜選
択される。また、原料粉体と粉砕媒体との混合比率は、
原料粉体の種類や、粉砕媒体の形状やその使用形態すな
わち、球状粉砕媒体単独であるか、球状と棒状粉砕媒体
との組み合わせであるか等により異なるものの、重量比
で、原料粉体１００に対して、粉砕媒体１００〜１００
０、好ましくは原料粉体１００に対して、粉砕媒体２０
０〜５００の比率で混合し、回転式加熱炉内に導入され
る。これら原料粉体と粉砕媒体とを、回転式加熱炉に導
入して窒化処理を行う。反応条件は、原料粉体の種類や
形状により多少異なるものの、水素ガス等の還元性ガ
ス、窒素ガスやアルゴンガス等の不活性ガスまたはこれ
らの混合ガスからなるキャリアガスと、アンモニアガス
等の窒化性ガスとから構成され、これらのガスを体積比
で、キャリアガス（還元性ガス＋不活性ガス）１００に
対して、窒化性ガス４００〜０．０１の範囲で混合して
なる窒化性雰囲気中で、温度２００〜１０００℃、好ま
しくは２００〜８００℃で、０．５〜１０時間加熱して
行われる。また、反応に先立ち、界面活性剤としての作
用をもつ適切な分散剤を、原料粉体に添加しておくこと
は、本方法において生成する粉体の焼結を防ぐという作
用効果を更に顕著にするのに好適な場合がある。このよ
うな反応条件により得られる窒化物粉体は、粒径０．０
５〜１００μｍの粒度分布をもち、粒径０．５〜３μｍ
の範囲に属するものが全体の８５〜９６％を占め、目的
とする粒径１μｍ付近の窒化物粉体を多量に得ることが
できる。Means and Actions for Solving the Problems The present inventors have
As a result of earnest research to solve the above-mentioned problems regarding the production of metal nitride powder, a method using a firing device, which is an inexpensive production method, was adopted, and the desired sintering was performed by forcibly releasing the sintering. The present invention has been completed by finding a method capable of obtaining a large amount of fine nitride powder having a particle size of about 1 μm, efficiently and at low cost. That is, a grinding medium is introduced into the rotary heating furnace together with the raw material powder, and the powder is crushed and ground at the same time as the nitriding reaction is caused in the high temperature nitriding atmosphere while strongly stirring the both by rotation. It is possible to obtain a metal nitride in which body particles do not sinter. The raw material powder used for producing the nitride powder according to the present invention is a metal or alloy, an intermetallic compound,
Further, they are made of metal compounds such as oxides and chlorides and have a diameter of 0.05 to 10 μm, preferably 0.1 to 1
It is a powder of μm. The type of metal is not particularly limited, and a metal or alloy used as a normal magnetic material, or an intermetallic compound such as iron or cobalt,
In addition to metals and alloys such as nickel, manganese and chromium, or intermetallic compounds containing them, various metals and alloys such as aluminum, titanium, silicon and rare earth metals such as neodymium and samarium, or intermetallic compounds containing them Can be mentioned. As the grinding medium introduced into the rotary heating furnace together with these raw material powders, it is preferable that they are formed of a substance which does not affect the raw material powders by contamination and is excellent in thermal and mechanical strength. , If the raw material powder is iron, convert the grinding medium made of pure iron or iron alloy, and if it is aluminum, convert it to ceramics such as aluminum oxide, aluminum nitride, aluminum boride, etc. Are used in enhanced form. The shape is not particularly limited, but the diameter is 0.2 to 30 mm, preferably 0.5 to
Small spheres of 10 mm can be used alone or in combination of small spheres having different diameters. Further, the shape is not limited to the spherical shape, and may be a rod shape having the same size. Further, spherical and rod-shaped ones may be used in combination. For example, when the raw material powder is iron, iron balls having a diameter of several mm can be used alone, or two or more kinds of iron balls having different diameters can be used in combination, or iron balls can be used in combination with iron rods. As described above, the grinding medium is appropriately selected according to the type and particle size of the raw material powder and the intended shape of the produced nitride. In addition, the mixing ratio of the raw material powder and the grinding medium is
Although it differs depending on the type of the raw material powder, the shape of the pulverizing medium and the usage thereof, that is, whether it is a spherical pulverizing medium alone or a combination of spherical and rod-like pulverizing media, the raw material powder 100 has a weight ratio. On the other hand, grinding medium 100 to 100
0, preferably 100 raw material powders to 20 grinding media 20
The mixture is mixed at a ratio of 0 to 500 and introduced into a rotary heating furnace. The raw material powder and the grinding medium are introduced into a rotary heating furnace for nitriding treatment. Although the reaction conditions vary slightly depending on the type and shape of the raw material powder, a reducing gas such as hydrogen gas, an inert gas such as nitrogen gas or argon gas, or a carrier gas composed of a mixed gas thereof, and a nitriding gas such as ammonia gas. In a nitriding atmosphere in which the gas is mixed with a carrier gas (reducing gas + inert gas) 100 in a volume ratio of 400 to 0.01 in a range of 400 to 0.01. The heating is performed at a temperature of 200 to 1000 ° C., preferably 200 to 800 ° C. for 0.5 to 10 hours. In addition, by adding an appropriate dispersant having a function as a surfactant to the raw material powder prior to the reaction, the effect of preventing the sintering of the powder generated in this method becomes more remarkable. It may be suitable to do. The nitride powder obtained under such reaction conditions has a particle size of 0.0
Has a particle size distribution of 5 to 100 μm and a particle size of 0.5 to 3 μm
85% to 96% of the total particles belong to the above range, and a large amount of the target nitride powder having a particle size of about 1 μm can be obtained.
【実施例】次に、本発明に係る窒化物粉体の製造方法に
関して、実施例に基づいてより詳細に説明する。 〔実施例１〕平均粒径が約０．５μｍの四三酸化鉄粉
（戸田工業製）５００ｇと、直径１ｍｍの鉄球１ｋｇと
を回転式加熱炉に導入し、いったん反応系内部を真空と
し、窒素置換を行った後、反応室に毎分２．０リットル
の流量で窒素ガスを供給しながら毎分１００回転の速さ
で回転して、５００℃まで昇温した後、窒素ガスの供給
を停止し、次いで水素ガスを毎分２．０リットルの流量
で流しながら５００℃で２時間保持し、四三酸化鉄粉を
還元する。その後、温度を６００℃に上昇させ、窒素ガ
ス１．６リットルとアンモニアガス０．４リットルとか
らなる混合ガスを毎分２．０リットルの流量で流しなが
ら２時間保持する。その後、反応室を室温になるまで放
冷して、窒化鉄粉末４９０ｇを得た。得られた窒化鉄粉
末１の性状は、表１に示すとおりである。 〔実施例２〕約１００メッシュの粒度をもつ無水塩化鉄
粉（和光純薬製）４００ｇと、直径１ｍｍの鉄球０．５
ｋｇ、直径９．５ｍｍの鉄球０．５ｋｇとを回転式加熱
炉に導入し、反応系内部を真空とし、窒素置換を行った
後、反応室を毎分２．０リットルの流量で窒素ガスを供
給しながら毎分９０回転の速さで回転しながら、５００
℃まで昇温した後、窒素ガスの供給を停止し、次いでア
ンモニアガスを毎分２．０リットルの流量で流しながら
５００℃で２時間保持し、塩化鉄を窒化する。その後、
温度を６００℃に上昇させ、流入ガスを窒素ガス１．６
リットルとアンモニアガス０．４リットルとからなる混
合ガスを毎分２．０リットルの流量で流入しながら、２
時間保持する。その後、反応室を室温になるまで放冷し
て、窒化鉄粉末１４８ｇを得た。得られた窒化鉄粉末２
の性状は、表１に示すとおりである。EXAMPLES Next, the method for producing a nitride powder according to the present invention will be described in more detail based on examples. [Example 1] 500 g of iron oxide black powder (manufactured by Toda Kogyo Co., Ltd.) having an average particle size of about 0.5 µm and 1 kg of iron balls having a diameter of 1 mm were introduced into a rotary heating furnace, and the inside of the reaction system was evacuated once. After performing nitrogen replacement, while supplying nitrogen gas to the reaction chamber at a flow rate of 2.0 liters per minute, the reaction chamber was rotated at a speed of 100 rpm to raise the temperature to 500 ° C., and then nitrogen gas was supplied. Is stopped, and then hydrogen gas is flowed at a flow rate of 2.0 liters per minute, and the temperature is maintained at 500 ° C. for 2 hours to reduce the ferrosoferric oxide powder. Then, the temperature is raised to 600 ° C., and a mixed gas composed of 1.6 liters of nitrogen gas and 0.4 liters of ammonia gas is flown at a flow rate of 2.0 liters per minute and kept for 2 hours. Then, the reaction chamber was left to cool to room temperature to obtain 490 g of iron nitride powder. The properties of the obtained iron nitride powder 1 are as shown in Table 1. [Example 2] 400 g of anhydrous iron chloride powder (manufactured by Wako Pure Chemical Industries, Ltd.) having a particle size of about 100 mesh, and 0.5 mm of iron balls having a diameter of 1 mm
After introducing 0.5 kg and an iron ball 0.5 kg with a diameter of 9.5 mm into a rotary heating furnace and evacuating the inside of the reaction system to perform nitrogen substitution, the reaction chamber was purged with nitrogen gas at a flow rate of 2.0 liters per minute. 500 rpm while feeding at 90 rpm
After the temperature is raised to 0 ° C., the supply of nitrogen gas is stopped, and then ammonia gas is flown at a flow rate of 2.0 liters / min and held at 500 ° C. for 2 hours to nitride iron chloride. afterwards,
The temperature was raised to 600 ° C. and the inflow gas was changed to nitrogen gas 1.6
While injecting a mixed gas of liter and 0.4 liter of ammonia gas at a flow rate of 2.0 liters per minute, 2
Hold for time. Then, the reaction chamber was left to cool to room temperature to obtain 148 g of iron nitride powder. Obtained iron nitride powder 2
The properties are shown in Table 1.
【０００１】[0001]
【表１】 [Table 1]
【０００２】[0002]
【発明の効果】以上説明したとおり、本発明によると、
原料粉体とともに粉砕媒体を反応容器内に導入して、窒
化処理と同時に、生成する窒化物の粉砕を行うことによ
り、従来の方法では得られなかった粒径１μｍ程度の窒
化物粉体を、多量にかつ安価に製造することができる。
また、原料粉体と粉砕媒体の強制的な攪拌の効果によ
り、原料粉体が窒化性ガスと均一にかつよく接触するた
め、窒化反応は効率よく進み、窒化処理時間を短縮する
ことができ、同時に得られる窒化物粉体の組成並びに性
状の均一性は極めて高いものである。As described above, according to the present invention,
By introducing a grinding medium into the reaction vessel together with the raw material powder and performing nitriding treatment and grinding of the generated nitride, a nitride powder having a particle diameter of about 1 μm, which cannot be obtained by the conventional method, is obtained. It can be manufactured in large quantities and at low cost.
Further, due to the effect of forcibly stirring the raw material powder and the grinding medium, the raw material powder uniformly and well contacts the nitriding gas, the nitriding reaction proceeds efficiently, it is possible to shorten the nitriding treatment time, The uniformity of composition and properties of the nitride powder obtained at the same time is extremely high.
【手続補正書】[Procedure amendment]
【提出日】平成６年３月２５日[Submission date] March 25, 1994
【手続補正１】[Procedure Amendment 1]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】全文[Correction target item name] Full text
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【書類名】 明細書[Document name] Statement
【発明の名称】 窒化物粉体の製造方法Title of the Invention Method for producing nitride powder
【特許請求の範囲】[Claims]
【発明の詳細な説明】Detailed Description of the Invention
【０００１】[0001]
【産業上の利用分野】本発明は、窒化物粉体の製造方法
に関し、より詳細には窒化物ファインセラミックス原料
粉体や磁性トナー用原料粉体、磁気記録材料用原料粉体
に好適な窒化物粉体の製造方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a nitride powder, and more particularly to a nitride powder suitable for a nitride fine ceramics raw material powder, a magnetic toner raw material powder, and a magnetic recording material raw material powder. The present invention relates to a method for producing powder.
【０００２】[0002]
【従来の技術】従来より、ファインセラミックスや磁性
トナー、磁気記録材料等の原料として、金属や金属酸化
物、金属塩化物等の粉体に窒化処理を施した金属窒化物
粉体が用いられている。この金属窒化物を製造する方法
として、種々の方法が提案、実施されており、例えば、
窒化鉄粉体については、窒化性雰囲気において、プラズ
マアーク中に鉄の粉末を供給する方法や、プラズマアー
クにより鉄を蒸発させて鉄蒸気とし、これに窒素ガスを
供給することにより、粒径０．０１μｍ程度の窒化鉄の
超微粒子を製造している。2. Description of the Related Art Conventionally, metal nitride powder obtained by nitriding powder of metal, metal oxide, metal chloride, etc. has been used as a raw material for fine ceramics, magnetic toner, magnetic recording materials and the like. There is. As a method for producing this metal nitride, various methods have been proposed and carried out, for example,
Regarding the iron nitride powder, in a nitriding atmosphere, iron powder is supplied into the plasma arc, or iron is vaporized by the plasma arc to form iron vapor, and nitrogen gas is supplied to this to obtain a particle size of 0. Ultrafine iron nitride particles of about 0.01 μm are manufactured.
【０００３】また、金属蒸気や金属塩化物等の蒸気を、
アンモニアガスと還元性のガス雰囲気中で反応させて金
属窒化物の微粉末を製造する方法も採られている。更
に、ロータリキルン等の焼成装置を用いて、高温窒化性
雰囲気中に原料粉体を導入し、原料粉体の窒化物を製造
する方法も一般的である。In addition, the vapor of metal vapor or metal chloride,
There is also adopted a method of producing fine powder of metal nitride by reacting with ammonia gas in a reducing gas atmosphere. Further, a method of producing a nitride of the raw material powder by introducing the raw material powder into a high temperature nitriding atmosphere using a rotary kiln or the like is also common.
【０００４】[0004]
【発明が解決しようとする課題】これらの窒化物粉体
は、最終製品の性能の点では、一般的にその粒径が小さ
い程好ましいとされているが、粒径が小さくなりすぎる
とその加工性において種々の困難な問題が生じる。すな
わち磁性トナーでは、磁性体粒子を樹脂などで被覆ある
いは樹脂と混練する必要があるが、このとき粒子が小さ
すぎると磁性体粒子の体積充填率が下がり、被覆材を含
めた全体としての磁化の値が小さくなったり、凝集によ
り製品に不均一性が発生する。In view of the performance of the final product, it is generally said that the smaller the particle size of these nitride powders, the more preferable it is. A variety of difficult problems arise in sex. That is, in the magnetic toner, it is necessary to coat or knead the magnetic particles with a resin or the like, but if the particles are too small at this time, the volume filling rate of the magnetic particles decreases and the magnetic properties of the entire magnet including the coating material are reduced. The product becomes inhomogeneous due to the small value or aggregation.
【０００５】このように、窒化物粉体は、その用途に応
じた好ましい粒径範囲があり、ファインセラミックス原
料としては、平均粒径が０．２〜１０μｍ程度、磁性ト
ナーとしては数μｍ以下、また磁気記録材料としては
０．５〜数μｍ程度であることが望ましく、概ね平均粒
径が１μｍ程度であれば、これらの用途に共通して、し
かも好適なものとして使用することができる。As described above, the nitride powder has a preferable particle size range according to its use. The fine ceramic raw material has an average particle size of about 0.2 to 10 μm, and the magnetic toner is several μm or less. Further, the magnetic recording material is preferably about 0.5 to several μm, and if the average particle diameter is about 1 μm, the magnetic recording material can be commonly used for these applications and can be suitably used.
【０００６】しかし、前記の方法では、粒径１μｍ程度
の窒化物の微粉末を、効率良く、しかも安価に得ること
は困難であった。例えばプラズマ法によれば、粒径が
０．０１μｍという超微粉末を得ることができるもの
の、逆に１μｍ程度の粒径のものを多量に得ることが難
しく、また、金属や金属塩化物の蒸気を窒化する方法で
は、生成窒化物が数珠状の連続体となり、単粒子が得ら
れないという問題を抱えていた。However, according to the above method, it is difficult to efficiently obtain a fine powder of nitride having a particle size of about 1 μm at a low cost. For example, according to the plasma method, although an ultrafine powder having a particle size of 0.01 μm can be obtained, it is difficult to obtain a large amount of particles having a particle size of about 1 μm, and vapor of metal or metal chloride In the method of nitriding, the produced nitride becomes a beaded continuous body, and there is a problem that single particles cannot be obtained.
【０００７】これら生成窒化物の生産性や形状の問題に
加えて、プラズマを発生させたり、原料を一度蒸発させ
たりする必要があるため、大量の電力または熱エネルギ
ーを必要とし、製造装置が高価になるとともに、反応条
件の制御等の製造プロセスも複雑になり、結果的に製造
コストが上昇し、製品として非常に高価なものになって
いた。In addition to the problems of productivity and shape of these produced nitrides, a large amount of electric power or thermal energy is required because it is necessary to generate plasma or vaporize the raw material once, and the manufacturing apparatus is expensive. In addition, the manufacturing process such as the control of reaction conditions becomes complicated, resulting in an increase in manufacturing cost and a very expensive product.
【０００８】一方、ロータリキルン等の焼成装置を用い
て窒化物粉体を製造する方法では、安価に、しかも多量
に窒化物を製造することができるが、処理できる原料粉
体の粒径に制限があり、通常粒径が数μｍ〜数十μｍ程
度の粗粒粉末は処理することができるが、粒径１μｍ程
度の粉体を処理しようとすると、粉体は、その表面エネ
ルギーが大きいために、反応中にキルン内壁面に付着し
たり、粒子同士が焼結を起こして大きな粒塊となってし
まう。この焼結体となった粒塊は硬度が高いために、１
μｍ程度の粒径まで粉砕するには非常に長い時間と大き
な機械的エネルギーを要し、必ずしも実用的ではなかっ
た。On the other hand, in the method of producing a nitride powder by using a calcining device such as a rotary kiln, the nitride can be produced inexpensively and in a large amount, but the particle size of the raw material powder that can be processed is limited. However, it is possible to process coarse powder having a particle size of several μm to several tens of μm, but when a powder having a particle size of about 1 μm is processed, the powder has a large surface energy. During the reaction, they may adhere to the inner wall surface of the kiln, or particles may sinter to form a large agglomerate. Since the agglomerates that became this sintered body have high hardness, 1
Grinding to a particle size of about μm requires a very long time and a large mechanical energy, and is not always practical.
【０００９】すなわち従来の方法では、ファインセラミ
ックスや磁性トナー、磁気記録材料等の原料として好適
な粒径１μｍ程度の窒化物の微粉末を、安価に、しかも
効率良く得ることは困難であった。従って、本発明の目
的は、粒径１μｍ程度の微細な窒化物粉体を、多量にか
つ、窒化処理後に粉砕等の後処理を必要せずに効率良
く、しかも安価に製造することにある。That is, according to the conventional method, it has been difficult to inexpensively and efficiently obtain fine powder of nitride, which is suitable as a raw material for fine ceramics, magnetic toners, magnetic recording materials and the like, and has a particle size of about 1 μm. Therefore, an object of the present invention is to manufacture a large amount of fine nitride powder having a particle size of about 1 μm, efficiently and inexpensively without requiring post-treatment such as crushing after nitriding treatment.
【００１０】[0010]
【課題を解決するための手段及び作用】本発明者らは、
金属窒化物粉体の製造に関する上記課題を解決すべく鋭
意研究の結果、安価な製造方法である焼成装置を用いた
方法を採用し、窒化反応において強制的に焼結を解くこ
とにより、所望の粒径１μｍ程度の微細な窒化物粉体を
多量にかつ効率良く、しかも安価に得ることができる方
法を見出し、本発明を完成するに至った。Means and Actions for Solving the Problems The present inventors have
As a result of earnest research to solve the above-mentioned problems regarding the production of metal nitride powder, a method using a firing device, which is an inexpensive production method, was adopted, and the desired sintering was performed by forcibly releasing the sintering. The present invention has been completed by finding a method capable of obtaining a large amount of fine nitride powder having a particle size of about 1 μm, efficiently and at low cost.
【００１１】すなわち回転式加熱炉内に、原料粉体とと
もに粉砕媒体を導入し、回転により両者を強く攪拌しな
がら高温の窒化性雰囲気において、窒化反応を起こさせ
ると同時に解砕並びに粉砕を行うことにより、粉体粒子
同志が焼結しない金属窒化物を得ることができる。本発
明に係る窒化物粉体の製造に用いられる原料粉体は、金
属や合金、金属間化合物、さらにそれらの酸化物や塩化
物等の金属化合物からなり、直径が０．０５〜１０μ
ｍ、好ましくは０．１〜１μｍの粉体である。また、金
属の種類は、特に制限されるものではなく、通常の磁性
材料として使用される金属や合金、あるいは金属間化合
物例えば、鉄やコバルト、ニッケル、マンガン、クロム
等の金属や合金、あるいはそれらを含む金属間化合物の
他にも、アルミニウムやチタン、シリコンおよびネオジ
ウム、サマリウム等の希土類金属等種々の金属や合金、
あるいはそれらを含む金属間化合物を挙げることができ
る。That is, the pulverizing medium is introduced into the rotary heating furnace together with the raw material powder, and both are crushed and crushed at the same time as the nitriding reaction is caused in a high temperature nitriding atmosphere while strongly stirring the both. This makes it possible to obtain a metal nitride in which powder particles do not sinter. The raw material powder used in the production of the nitride powder according to the present invention is composed of a metal compound such as a metal, an alloy, an intermetallic compound, or an oxide or chloride thereof, and has a diameter of 0.05 to 10 μm.
m, preferably 0.1 to 1 μm. Further, the kind of metal is not particularly limited, and a metal or alloy used as a usual magnetic material, or an intermetallic compound, for example, a metal or alloy such as iron, cobalt, nickel, manganese, or chromium, or those In addition to intermetallic compounds containing, various metals and alloys such as aluminum and titanium, silicon and neodymium, rare earth metals such as samarium,
Alternatively, an intermetallic compound containing them can be mentioned.
【００１２】これら原料粉体とともに回転式加熱炉に導
入される粉砕媒体としては、原料粉体に汚染の影響を与
えず、かつ熱的、機械的強度に優れた物質から形成され
ていることが好ましく、例えば、原料粉体が鉄の場合に
は、純鉄または鉄合金からなる粉砕媒体を、またアルミ
ニウムの場合には、酸化アルミニウムや窒化アルミニウ
ム、ほう化アルミニウム等のセラミックスに変換して、
その機械的強度が増強された形態で使用される。The pulverizing medium introduced into the rotary heating furnace together with these raw material powders is formed of a substance which does not affect the raw material powders by contamination and is excellent in thermal and mechanical strength. Preferably, for example, when the raw material powder is iron, a grinding medium made of pure iron or an iron alloy, and in the case of aluminum, is converted to ceramics such as aluminum oxide, aluminum nitride, and aluminum boride,
It is used in a form whose mechanical strength is enhanced.
【００１３】また、その形状は、特に制限されるもので
はないが、直径０．２〜３０ｍｍ、好ましくは０．５〜
１０ｍｍの小球を、単独または直径の異なる小球を適宜
組み合わせて使用することができる。また、球状に限ら
ず、同様の大きさを有する棒状でも構わない。更に、球
状と棒状のものを組み合わせて使用してもよい。例え
ば、原料粉体が鉄の場合には、直径数ｍｍの鉄球を単独
に、あるいは直径の異なる２種類以上の鉄球を組み合わ
せて、また鉄球に鉄棒を組み合わせて使用することがで
きる。The shape is not particularly limited, but the diameter is 0.2-30 mm, preferably 0.5-.
Small spheres of 10 mm can be used alone or in combination of small spheres having different diameters. Further, the shape is not limited to the spherical shape, and may be a rod shape having the same size. Further, spherical and rod-shaped ones may be used in combination. For example, when the raw material powder is iron, iron balls having a diameter of several mm can be used alone, or two or more kinds of iron balls having different diameters can be used in combination, or iron balls can be used in combination with iron rods.
【００１４】このように、粉砕媒体は、原料粉体の種類
や粒径、また生成窒化物の目的とされる形状に応じて適
宜選択される。また、原料粉体と粉砕媒体との混合比率
は、原料粉体の種類や、粉砕媒体の形状やその使用形態
すなわち、球状粉砕媒体単独であるか、球状と棒状粉砕
媒体との組み合わせであるか等により異なるものの、重
量比で、原料粉体１００に対して、粉砕媒体１００〜１
０００、好ましくは原料粉体１００に対して、粉砕媒体
２００〜５００の比率で混合し、回転式加熱炉内に導入
される。As described above, the grinding medium is appropriately selected according to the kind and particle size of the raw material powder and the intended shape of the produced nitride. Further, the mixing ratio of the raw material powder and the pulverizing medium is the kind of the raw material powder, the shape of the pulverizing medium and the usage form thereof, that is, the spherical pulverizing medium alone or the combination of the spherical and rod-like pulverizing media. Etc., but in a weight ratio, 100 to 1 of the pulverizing medium to the raw material powder 100
000, preferably 100 of the raw material powder, is mixed at a ratio of 200 to 500 as the grinding medium and introduced into the rotary heating furnace.
【００１５】これら原料粉体と粉砕媒体とを、回転式加
熱炉に導入して窒化処理を行う。反応条件は、原料粉体
の種類や形状により多少異なるものの、水素ガス等の還
元性ガス、窒素ガスやアルゴンガス等の不活性ガスまた
はこれらの混合ガスからなるキャリアガスと、アンモニ
アガス等の窒化性ガスとから構成され、これらのガスを
体積比で、キャリアガス（還元性ガス＋不活性ガス）１
００に対して、窒化性ガス４００〜０．０１の範囲で混
合してなる窒化性雰囲気中で、温度２００〜１０００
℃、好ましくは２００〜８００℃で、０．５〜１０時間
加熱して行われる。The raw material powder and the grinding medium are introduced into a rotary heating furnace for nitriding treatment. Although the reaction conditions vary slightly depending on the type and shape of the raw material powder, a reducing gas such as hydrogen gas, an inert gas such as nitrogen gas or argon gas, or a carrier gas composed of a mixed gas thereof, and a nitriding gas such as ammonia gas. 1) carrier gas (reducing gas + inert gas) by volume ratio of these gases.
00 in a nitriding atmosphere in which a nitriding gas is mixed in the range of 400 to 0.01 at a temperature of 200 to 1000.
It heats at 0.5 degreeC, preferably 200-800 degreeC, and is performed for 0.5 to 10 hours.
【００１６】また、反応に先立ち、界面活性剤としての
作用をもつ適切な分散剤を、原料粉体に添加しておくこ
とは、本方法において生成する粉体の焼結を防ぐという
作用効果を更に顕著にするのに好適な場合がある。この
ような反応条件により得られる窒化物粉体は、粒径０．
０５〜１００μｍの粒度分布をもち、粒径０．５〜３μ
ｍの範囲に属するものが全体の８５〜９６％を占め、目
的とする粒径１μｍ付近の窒化物粉体を多量に得ること
ができる。In addition, adding a suitable dispersant having a function as a surfactant to the raw material powder prior to the reaction has the effect of preventing sintering of the powder produced in this method. It may be preferable to make it more remarkable. The nitride powder obtained under such reaction conditions has a particle size of 0.
Has a particle size distribution of 05 to 100 μm and a particle size of 0.5 to 3 μm.
Those belonging to the range of m occupy 85 to 96% of the whole, and it is possible to obtain a large amount of the target nitride powder having a particle size of about 1 μm.
【００１７】[0017]
【実施例】次に、本発明に係る窒化物粉体の製造方法に
関して、実施例に基づいてより詳細に説明する。 〔実施例１〕平均粒径が約０．５μｍの四三酸化鉄粉
（戸田工業製）５００ｇと、直径１ｍｍの鉄球１ｋｇと
を回転式加熱炉に導入し、いったん反応系内部を真空と
し、窒素置換を行った後、反応室に毎分２．０リットル
の流量で窒素ガスを供給しながら毎分１００回転の速さ
で回転して、５００℃まで昇温した後、窒素ガスの供給
を停止し、次いで水素ガスを毎分２．０リットルの流量
で流しながら５００℃で２時間保持し、四三酸化鉄粉を
還元する。その後、温度を６００℃に上昇させ、窒素ガ
ス１．６リットルとアンモニアガス０．４リットルとか
らなる混合ガスを毎分２．０リットルの流量で流しなが
ら２時間保持する。その後、反応室を室温になるまで放
冷して、窒化鉄粉末４９０ｇを得た。得られた窒化鉄粉
末１の性状は、表１に示すとおりである。 〔実施例２〕約１００メッシュの粒度をもつ無水塩化鉄
粉（和光純薬製）４００ｇと、直径１ｍｍの鉄球０．５
ｋｇ、直径９．５ｍｍの鉄球０．５ｋｇとを回転式加熱
炉に導入し、反応系内部を真空とし、窒素置換を行った
後、反応室を毎分２．０リットルの流量で窒素ガスを供
給しながら毎分９０回転の速さで回転しながら、５００
℃まで昇温した後、窒素ガスの供給を停止し、次いでア
ンモニアガスを毎分２．０リットルの流量で流しながら
５００℃で２時間保持し、塩化鉄を窒化する。その後、
温度を６００℃に上昇させ、流入ガスを窒素ガス１．６
リットルとアンモニアガス０．４リットルとからなる混
合ガスを毎分２．０リットルの流量で流入しながら、２
時間保持する。その後、反応室を室温になるまで放冷し
て、窒化鉄粉末１４８ｇを得た。得られた窒化鉄粉末２
の性状は、表１に示すとおりである。EXAMPLES Next, the method for producing a nitride powder according to the present invention will be described in more detail based on examples. [Example 1] 500 g of iron oxide black powder (manufactured by Toda Kogyo Co., Ltd.) having an average particle size of about 0.5 µm and 1 kg of iron balls having a diameter of 1 mm were introduced into a rotary heating furnace, and the inside of the reaction system was evacuated once. After performing nitrogen replacement, while supplying nitrogen gas to the reaction chamber at a flow rate of 2.0 liters per minute, the reaction chamber was rotated at a speed of 100 rpm to raise the temperature to 500 ° C., and then nitrogen gas was supplied. Is stopped, and then hydrogen gas is flowed at a flow rate of 2.0 liters per minute, and the temperature is maintained at 500 ° C. for 2 hours to reduce the ferrosoferric oxide powder. Then, the temperature is raised to 600 ° C., and a mixed gas composed of 1.6 liters of nitrogen gas and 0.4 liters of ammonia gas is flown at a flow rate of 2.0 liters per minute and kept for 2 hours. Then, the reaction chamber was left to cool to room temperature to obtain 490 g of iron nitride powder. The properties of the obtained iron nitride powder 1 are as shown in Table 1. [Example 2] 400 g of anhydrous iron chloride powder (manufactured by Wako Pure Chemical Industries, Ltd.) having a particle size of about 100 mesh, and 0.5 mm of iron balls having a diameter of 1 mm
After introducing 0.5 kg and an iron ball 0.5 kg with a diameter of 9.5 mm into a rotary heating furnace and evacuating the inside of the reaction system to perform nitrogen substitution, the reaction chamber was purged with nitrogen gas at a flow rate of 2.0 liters per minute. 500 rpm while feeding at 90 rpm
After the temperature is raised to 0 ° C., the supply of nitrogen gas is stopped, and then ammonia gas is flown at a flow rate of 2.0 liters / min and held at 500 ° C. for 2 hours to nitride iron chloride. afterwards,
The temperature was raised to 600 ° C. and the inflow gas was changed to nitrogen gas 1.6
While injecting a mixed gas of liter and 0.4 liter of ammonia gas at a flow rate of 2.0 liters per minute, 2
Hold for time. Then, the reaction chamber was left to cool to room temperature to obtain 148 g of iron nitride powder. Obtained iron nitride powder 2
The properties are shown in Table 1.
【００１８】[0018]
【表１】 [Table 1]
【００１９】[0019]
【発明の効果】以上説明したとおり、本発明によると、
原料粉体とともに粉砕媒体を反応容器内に導入して、窒
化処理と同時に、生成する窒化物の粉砕を行うことによ
り、従来の方法では得られなかった粒径１μｍ程度の窒
化物粉体を、多量にかつ安価に製造することができる。As described above, according to the present invention,
By introducing a grinding medium into the reaction vessel together with the raw material powder and performing nitriding treatment and grinding of the generated nitride, a nitride powder having a particle diameter of about 1 μm, which cannot be obtained by the conventional method, is obtained. It can be manufactured in large quantities and at low cost.
【００２０】また、原料粉体と粉砕媒体の強制的な攪拌
の効果により、原料粉体が窒化性ガスと均一にかつよく
接触するため、窒化反応は効率よく進み、窒化処理時間
を短縮することができ、同時に得られる窒化物粉体の組
成並びに性状の均一性は極めて高いものである。Further, since the raw material powder comes into uniform and good contact with the nitriding gas due to the effect of forcibly stirring the raw material powder and the grinding medium, the nitriding reaction proceeds efficiently and the nitriding treatment time is shortened. And the uniformity of the composition and properties of the nitride powder obtained at the same time is extremely high.
Claims (1)
料とする粉体とともに粉砕媒体を高温、窒化性雰囲気内
に共存させ、かつ両者を揺動させ攪拌しながら、窒化反
応を行うことを特徴とする窒化物粉体の製造方法。1. In a method for producing a nitride powder, a nitriding reaction is carried out by coexisting a powder as a raw material with a grinding medium in a nitriding atmosphere at a high temperature, and agitating both by shaking them. A method for producing a characteristic nitride powder.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP06146593A JP3362742B2 (en) | 1993-02-26 | 1993-02-26 | Method for producing nitride powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP06146593A JP3362742B2 (en) | 1993-02-26 | 1993-02-26 | Method for producing nitride powder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH06256006A true JPH06256006A (en) | 1994-09-13 |
| JP3362742B2 JP3362742B2 (en) | 2003-01-07 |
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ID=13171824
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP06146593A Expired - Fee Related JP3362742B2 (en) | 1993-02-26 | 1993-02-26 | Method for producing nitride powder |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107010610A (en) * | 2017-06-13 | 2017-08-04 | 王兆兵 | A kind of energy-efficient high purity silicon nitride manganese production system |
-
1993
- 1993-02-26 JP JP06146593A patent/JP3362742B2/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107010610A (en) * | 2017-06-13 | 2017-08-04 | 王兆兵 | A kind of energy-efficient high purity silicon nitride manganese production system |
| CN107010610B (en) * | 2017-06-13 | 2023-09-19 | 王兆兵 | High-efficiency energy-saving high-purity manganese nitride production system |
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| Publication number | Publication date |
|---|---|
| JP3362742B2 (en) | 2003-01-07 |
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