JPS5855201B2 - Method for producing metal fine particles - Google Patents
Method for producing metal fine particlesInfo
- Publication number
- JPS5855201B2 JPS5855201B2 JP54107572A JP10757279A JPS5855201B2 JP S5855201 B2 JPS5855201 B2 JP S5855201B2 JP 54107572 A JP54107572 A JP 54107572A JP 10757279 A JP10757279 A JP 10757279A JP S5855201 B2 JPS5855201 B2 JP S5855201B2
- Authority
- JP
- Japan
- Prior art keywords
- fine particles
- metal fine
- temperature
- heat treatment
- metal
- 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.)
- Expired
Links
- 239000010419 fine particle Substances 0.000 title claims description 38
- 229910052751 metal Inorganic materials 0.000 title claims description 36
- 239000002184 metal Substances 0.000 title claims description 36
- 238000004519 manufacturing process Methods 0.000 title claims description 9
- 238000010438 heat treatment Methods 0.000 claims description 25
- 238000000034 method Methods 0.000 claims description 14
- 230000001590 oxidative effect Effects 0.000 claims description 8
- 239000002923 metal particle Substances 0.000 description 10
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 9
- 229910001111 Fine metal Inorganic materials 0.000 description 8
- 230000005415 magnetization Effects 0.000 description 8
- 238000005245 sintering Methods 0.000 description 6
- 239000007864 aqueous solution Substances 0.000 description 5
- 238000001035 drying Methods 0.000 description 5
- 239000007789 gas Substances 0.000 description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 4
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 4
- 230000004907 flux Effects 0.000 description 4
- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 239000012279 sodium borohydride Substances 0.000 description 2
- 229910000033 sodium borohydride Inorganic materials 0.000 description 2
- 239000007858 starting material Substances 0.000 description 2
- VKEQBMCRQDSRET-UHFFFAOYSA-N Methylone Chemical compound CNC(C)C(=O)C1=CC=C2OCOC2=C1 VKEQBMCRQDSRET-UHFFFAOYSA-N 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 229940044175 cobalt sulfate Drugs 0.000 description 1
- 229910000361 cobalt sulfate Inorganic materials 0.000 description 1
- KTVIXTQDYHMGHF-UHFFFAOYSA-L cobalt(2+) sulfate Chemical compound [Co+2].[O-]S([O-])(=O)=O KTVIXTQDYHMGHF-UHFFFAOYSA-L 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000003795 desorption Methods 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 235000003891 ferrous sulphate Nutrition 0.000 description 1
- 239000011790 ferrous sulphate Substances 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 description 1
- 229910000359 iron(II) sulfate Inorganic materials 0.000 description 1
- 150000002576 ketones Chemical class 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- -1 methyl ethyl ketone Chemical compound 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
- H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
- H01F1/032—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials
- H01F1/04—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys
- H01F1/06—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys in the form of particles, e.g. powder
- H01F1/061—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys in the form of particles, e.g. powder with a protective layer
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
- B22F1/14—Treatment of metallic powder
- B22F1/142—Thermal or thermo-mechanical treatment
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
- H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
- H01F1/032—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials
- H01F1/04—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys
- H01F1/06—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys in the form of particles, e.g. powder
- H01F1/065—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys in the form of particles, e.g. powder obtained by a reduction
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Hard Magnetic Materials (AREA)
- Manufacture Of Metal Powder And Suspensions Thereof (AREA)
- Powder Metallurgy (AREA)
Description
【発明の詳細な説明】
本発明は、高密度磁気記録媒体用の金属微粒子の製造方
法に関し、更に詳しくは、湿式還元法によって得られた
金属微粒子の熱処理に係るものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing fine metal particles for high-density magnetic recording media, and more specifically to heat treatment of fine metal particles obtained by a wet reduction method.
家庭用ＶＴＲの普及や、高性能オーディオカセットの実
用化に代表されるように、近年の磁気記録装置の進歩、
発展に伴い、それに使用される磁気記録媒体も記録の高
密度化が要求されるようになってきた。Advances in magnetic recording devices in recent years, as exemplified by the spread of home VTRs and the practical use of high-performance audio cassettes,
As the technology advances, the magnetic recording media used therein are required to have higher recording densities.
このような磁気記録の高密度化の要求に合うものとして
、水素化ホウ素ナトリウムあるいは水素化ホウ素カリウ
ム等の強制還元剤を用いた湿式還元法による金属微粒子
が知られている。Metal fine particles produced by a wet reduction method using a forced reducing agent such as sodium borohydride or potassium borohydride are known as materials that meet the demands for higher density magnetic recording.
この湿式還元法によって得られた金属微粒子は、保磁力
Ｈｃ＝６００〜１８５０ （Ｏｅ ）、飽和磁化（７８
８０〜１２０ （ｅｍｕ ７ｇ ）、角型比＝０．４〜
０．６の優れた磁気特性を示す。The metal fine particles obtained by this wet reduction method have a coercive force Hc of 600 to 1850 (Oe) and a saturation magnetization of 78
80-120 (emu 7g), squareness ratio = 0.4-
It shows excellent magnetic properties of 0.6.
しかしながら、現在、高密度磁気記録媒体に要求されて
いる磁気特性は、前掲の水準を超えるものであり、より
一層高い保磁力、飽和磁束密度および角型比を有する金
属微粒子の開発が望まれている。However, the magnetic properties currently required for high-density magnetic recording media exceed the above-mentioned standards, and it is desired to develop metal fine particles with even higher coercive force, saturation magnetic flux density, and squareness ratio. There is.
湿式還元法によって得られた金属微粒子を、２００〜４
００℃の還元性雰囲気中で熱処理することにより、磁気
特性が幾分改善された金属微粒子を得ることができるが
、それ以上に改善された金属微粒子を得るには、さらに
高温の熱処理が必要となる。The metal fine particles obtained by the wet reduction method were
Metal fine particles with somewhat improved magnetic properties can be obtained by heat treatment in a reducing atmosphere at 00°C, but in order to obtain metal fine particles with even further improvement, an even higher temperature heat treatment is required. Become.
しかし、熱処理温度が高くなると、金属微粒子間の焼結
の問題が大きくなり、高い飽和磁束密度を得ても、保磁
力あるいは角型比がかえって悪化するという問題があっ
たＯ
本発明は上述する従来の諸問題点を解決し、湿式還元法
により得られた金属微粒子に対して熱処理を施して特性
改善を図る場合に、その焼結を防ぎ、保磁力、飽和磁束
密度および角型比をより一層内上させることのできる、
金属微粒子の製造方法を提供することを目的とする。However, as the heat treatment temperature increases, the problem of sintering between fine metal particles increases, and even if a high saturation magnetic flux density is obtained, there is a problem that the coercive force or squareness ratio worsens. When solving the conventional problems and improving the properties of metal fine particles obtained by the wet reduction method, it is possible to prevent sintering and improve the coercive force, saturation magnetic flux density, and squareness ratio. It can make you feel even better,
The object of the present invention is to provide a method for producing metal fine particles.
上記目的を達成するため、本発明に係る製造方法は、湿
式還元法により得られた金属微粒子を、非酸化性雰囲気
または還元性雰囲気において、湿潤状態より低温加熱し
て、該金属微粒子中に含浸する水分を脱離する工程を経
た後、前記金属微粒子を前記工程よりは高い温度で熱処
理することを特徴とする。In order to achieve the above object, the manufacturing method according to the present invention involves heating fine metal particles obtained by a wet reduction method at a lower temperature than in a wet state in a non-oxidizing atmosphere or a reducing atmosphere to impregnate the fine metal particles into the fine metal particles. The method is characterized in that after the step of removing moisture, the metal fine particles are heat-treated at a temperature higher than that of the step.
次に本発明の内容を更に詳しぐ説明する。Next, the content of the present invention will be explained in more detail.
連続反応装置を用いて湿式還元法により得られた金属微
粒子を、水、メチルアルコール等のアルコール類、メチ
ルエチルケトン等のケトン類およびトルエン等の芳香族
の一種もしくはその混合液中に回収する。Fine metal particles obtained by a wet reduction method using a continuous reaction apparatus are recovered in water, alcohols such as methyl alcohol, ketones such as methyl ethyl ketone, and one type of aromatic group such as toluene, or a mixture thereof.
次にこれを、乾燥金属微粒子の重量に対し、併せて２〜
５倍重量部によるように絞る。Next, add a total of 2 to 20% of the weight of the dry metal fine particles.
Squeeze to 5 parts by weight.
この湿潤状態の金属微粒子を、回転型あるいは静置型の
還元炉内に入れる。The wet metal particles are placed in a rotary or stationary reduction furnace.
そしてこの還元炉を、常温〜２４０℃の非酸化性雰囲気
あるいは還元性雰囲気とし、０．５〜６時間低温処理し
、相対湿度で４０％以下となるように乾燥させる。Then, the reduction furnace is set to a non-oxidizing atmosphere or a reducing atmosphere at room temperature to 240° C., and low temperature treatment is performed for 0.5 to 6 hours, followed by drying to a relative humidity of 40% or less.
非酸化性雰囲気は窒素あるいはアルゴン等の不活性ガス
によって形成され、また還元性雰囲気は水素あるいは炭
酸ガスによって形成される。The non-oxidizing atmosphere is formed by an inert gas such as nitrogen or argon, and the reducing atmosphere is formed by hydrogen or carbon dioxide gas.
この加熱乾燥工程を経ることにより、次の熱処理工程に
おける金層微粒子相互間の焼結を防止することができる
。By going through this heating and drying step, it is possible to prevent the gold layer fine particles from sintering with each other in the next heat treatment step.
即ちこの乾燥工程は、次の熱処理工程に対し、焼結防止
のための前工程となる。That is, this drying step is a pre-step for the next heat treatment step to prevent sintering.
次に非酸化性あるいは還元性雰囲気内で、１°Ｃ／ｍｉ
ｎ、〜５℃／ｍｉｎ、の昇温速度で、炉内の温度を２０
０〜６００℃まで昇温させ、Ｏ〜１０時間程時間熱する
。Then, in a non-oxidizing or reducing atmosphere,
The temperature in the furnace was increased to 20°C at a heating rate of 5°C/min.
Raise the temperature to 0 to 600°C and heat for about 10 hours.
なお、前記低温処理の温度は１５０〜２００℃付近が最
も望ましく、高温加熱処理時の温度は３７０〜５００℃
付近が望ましい。The temperature of the low-temperature treatment is most preferably around 150 to 200°C, and the temperature of the high-temperature heat treatment is 370 to 500°C.
Preferably nearby.
また出発物質としての金属微粒子の初期特性が同じであ
っても、高温加熱時の温度あるいは加熱時間を適当に設
定することにより、用途に応じた特性の金属微粒子を得
ることも可能である。Further, even if the initial characteristics of the metal fine particles as a starting material are the same, by appropriately setting the temperature or heating time during high-temperature heating, it is possible to obtain metal fine particles with characteristics depending on the intended use.
上述した本発明に係る製造方法によれば、高温熱処理を
施す前に加熱乾燥工程を施すことにより、高温熱処理時
における金属微粒子の焼結を防止し、保磁力Ｈｃ＝６０
０〜２３５０（Ｏｅ）、飽和磁束密度σＳ二１００〜１
７５（ｅｍｕ／ｇ）、角型比０．５〜０．６の磁気特性
を有し、高密度磁気記録に最適な金属微粒子を容易に得
ることができる。According to the manufacturing method according to the present invention described above, by performing a heating drying step before performing high-temperature heat treatment, sintering of metal fine particles during high-temperature heat treatment is prevented, and coercive force Hc = 60
0 to 2350 (Oe), saturation magnetic flux density σS2100 to 1
75 (emu/g) and a squareness ratio of 0.5 to 0.6, metal fine particles suitable for high-density magnetic recording can be easily obtained.
しかも、焼結防止工程となる乾燥工程と次の熱処理工程
とを、非酸化性雰囲気または還元性雰囲気に保たれた同
一炉内で連続して行なうことが可能であり、金属微粒子
の製造能率が非常に高くなる。Moreover, the drying process, which is a sintering prevention process, and the next heat treatment process can be performed continuously in the same furnace maintained in a non-oxidizing atmosphere or reducing atmosphere, increasing the production efficiency of metal fine particles. becomes very expensive.
次に実施例および比較例をあげ、本発明の内容を更に具
体的に説明する。Next, the content of the present invention will be explained in more detail with reference to Examples and Comparative Examples.
実施例 １
Ｑ Ｆ ｅ Ｓ ０４ ・７ Ｈ２０（硫酸第１鉄水
溶液）０．７モル
ＣＯ３Ｏ４・７Ｈ２０（硫酸コバルト水溶液）０．３モ
ル
ＨＣｌ （塩酸水溶液）０．６モル（Ｂ）
ＮａＢＨ＋ （水素化ホウ素ナトリウム水溶液）１．０
モル
上記（４）および（Ｂ）の水溶液を、当モル反応するよ
うに連続反応装置を用いて反応させ、合金微粒子を得、
エタノール中に回収した。Example 1 Q Fe S 04 ・7 H20 (ferrous sulfate aqueous solution) 0.7 mol CO3O4 ・7H20 (cobalt sulfate aqueous solution) 0.3 mol HCl (hydrochloric acid aqueous solution) 0.6 mol (B)
NaBH+ (sodium borohydride aqueous solution) 1.0
The aqueous solutions of (4) and (B) above are reacted using a continuous reactor so as to react equimolarly to obtain alloy fine particles,
Collected in ethanol.
これを空気中で乾燥させると、保磁力Ｈｃ＝ １８２０
（Ｏｅ）、飽和磁化σｓ ＝ １３０．０ （ｅｍｕ
７ｇ ）、角型比０．５８の合金微粒子が得られた。When this is dried in the air, the coercive force Hc = 1820
(Oe), saturation magnetization σs = 130.0 (emu
7 g) and a squareness ratio of 0.58 were obtained.
この金属微粒子をＰｌとする。These metal fine particles are referred to as Pl.
エタノール中に回収されて湿潤状態にある金属微粒子（
Ｐ−１）を、溶質と溶媒を合わせた重量が、溶質の３〜
４倍重量となるように絞った後、静置型還元炉内に設置
した。Fine metal particles collected in ethanol and in a wet state (
P-1), the combined weight of the solute and solvent is 3 to 3 of the solute.
After squeezing the weight to 4 times its weight, it was placed in a stationary reduction furnace.
その後、還元炉内に還元性ガスとして水素ガスを流しな
がら炉を加熱し、１５０°Ｃの温度条件で、３時間の低
温熱処理を行なった。Thereafter, the furnace was heated while flowing hydrogen gas as a reducing gas into the reduction furnace, and low-temperature heat treatment was performed at a temperature of 150° C. for 3 hours.
処理最終時に炉から流出するガスの相対湿度は約３０％
であった。The relative humidity of the gas leaving the furnace at the end of the process is approximately 30%.
Met.
前述の低温熱処理後、さらに水素ガスを流しながら、還
元炉内の温度を３℃／ｍｉｄ、の昇温速度で５０５℃ま
で上昇させた直後に、室温まで冷却し、改善された金属
微粒子をトルエンに浸した。After the above-mentioned low-temperature heat treatment, the temperature inside the reduction furnace was raised to 505°C at a temperature increase rate of 3°C/mid while flowing hydrogen gas. Soaked in.
このようにして得られた金属微粒子は、保磁力Ｈｅ ＝
１９８０ （Ｏｅ）、飽和磁化σ５＝１４０．Ｏｅｍ
ｕ／ｇｓ角型比０．５８で、出発物質たる金属微粒子（
Ｐ−１）より、保磁力Ｈｃ、飽和磁化σＳがかなり改善
された。The metal fine particles obtained in this way have a coercive force He =
1980 (Oe), saturation magnetization σ5=140. Oem
With a u/gs squareness ratio of 0.58, the starting material metal fine particles (
P-1), the coercive force Hc and saturation magnetization σS were significantly improved.
実施例 ２
実施例１の湿式還元法で得られた金属微粒子（Ｐ−■）
を、実施例１で説明した還元炉内に設置し、この還元炉
内に非酸化性ガスたる窒素ガスを流しながら、１５０℃
の温度条件で３時間の低温熱処理を行なった。Example 2 Metal fine particles (P-■) obtained by the wet reduction method of Example 1
was installed in the reduction furnace described in Example 1, and heated to 150°C while flowing nitrogen gas, which is a non-oxidizing gas, into the reduction furnace.
A low-temperature heat treatment was performed for 3 hours under the following temperature conditions.
このとき炉流出ガスの相対湿度は約２０％であった。At this time, the relative humidity of the furnace outflow gas was about 20%.
上述の低温熱処理後、さらに３℃／ｍｉｎ、の昇温速度
で５１０°Ｃまで加熱して高温熱処理を行ない、次に室
温まで冷却してトルエン中に改善された金属微粒子を回
収した。After the above-mentioned low-temperature heat treatment, high-temperature heat treatment was performed by further heating to 510°C at a heating rate of 3°C/min, and then cooling to room temperature to collect the improved metal fine particles in toluene.
こうして得られた金属微粒子は、保磁力Ｈｃ１９５０（
Ｏｅ）、飽和磁化（７Ｓ ＝＝ １３８．０ （ｅｍｕ
／ｇ）、角型比０．５８であり、出発の金属微粒子（Ｐ
−１）より保磁力、飽和磁化がかなり改善された。The metal fine particles thus obtained have a coercive force of Hc1950 (
Oe), saturation magnetization (7S == 138.0 (emu
/g), the squareness ratio is 0.58, and the starting metal fine particles (P
-1) The coercive force and saturation magnetization were significantly improved.
比較例 １
実施例１における金属微粒子（Ｐ−１）を室温で乾燥さ
せて水分を完全に除去したものを、水素気流中で５００
℃まで加熱し、その直後に室温まで冷却してトルエン中
に金属微粒子を得た。Comparative Example 1 The metal fine particles (P-1) in Example 1 were dried at room temperature to completely remove moisture, and then dried at 500 ml in a hydrogen stream.
It was heated to .degree. C. and immediately cooled to room temperature to obtain metal fine particles in toluene.
この金属微粒子は保磁力Ｈｃ＝１５５０ （Ｏｅ）、飽
和磁化σｓ＝１２５（ｅｍｕ／ｇ）、角型比０．４９と
なり、出発金属微粒子（Ｐ−１）の磁気特性より、かえ
って劣化したものとなった。These metal fine particles had a coercive force Hc = 1550 (Oe), a saturation magnetization σs = 125 (emu/g), and a squareness ratio of 0.49, which indicates that the magnetic properties of the starting metal fine particles (P-1) were rather deteriorated. became.
以上述べたように本発明に係る製造方法は、湿式還元法
により得られた金属微粒子を、非酸化性雰囲気または還
元性雰囲気において、湿潤状態より低温加熱して該金属
微粒子中に含浸する水分を脱離する工程と、該工程に続
いて前記金属微粒子を前記工程よりは高い温度で熱処理
する工程とを含むことを特徴とするから、保磁力、飽和
磁化および角型比の全てにおいて改善された金属微粒子
を容易に製造することができる。As described above, the production method according to the present invention heats metal fine particles obtained by a wet reduction method at a lower temperature than in a wet state in a non-oxidizing atmosphere or a reducing atmosphere to remove moisture impregnated into the metal fine particles. Since it is characterized by including a step of desorption, and a step of heat-treating the metal fine particles at a temperature higher than that of the step, the coercive force, saturation magnetization, and squareness ratio are all improved. Metal fine particles can be easily produced.
したがって本発明によれば、高密度磁気記録媒体用とし
て誠に好適な金属粒子を、容易に製造することができる
。Therefore, according to the present invention, metal particles that are truly suitable for use in high-density magnetic recording media can be easily produced.
Claims (1)
性雰囲気または還元性雰囲気において、湿潤状態より低
温加熱して、該金属微粒子中に含浸される水分を脱離す
る工程と、該工程に続いて前記金属微粒子を前記工程よ
りは高い温度まで加熱する工程とを含むことを特徴とす
る金属微粒子の製造方法。 ２ 前記第１の工程は常温乃至２４０℃の温度条件で行
なうことを特徴とする特許請求の範囲第１項に記載の金
属微粒子の製造方法。 ３ 前記第２の工程は２００℃乃至６００℃の温度条件
で行なうことを特徴とする特許請求の範囲第１項または
第２項に記載の金属微粒子の製造方法。[Claims] 1. A step of heating metal fine particles obtained by a wet reduction method at a lower temperature than in a wet state in a non-oxidizing atmosphere or a reducing atmosphere to remove moisture impregnated in the metal fine particles. and a step of heating the metal fine particles to a temperature higher than that in the step, following the step. 2. The method for producing metal fine particles according to claim 1, wherein the first step is carried out at a temperature of room temperature to 240°C. 3. The method for producing metal fine particles according to claim 1 or 2, wherein the second step is carried out at a temperature of 200°C to 600°C.
Priority Applications (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP54107572A JPS5855201B2 (en) | 1979-08-23 | 1979-08-23 | Method for producing metal fine particles |
| GB8026454A GB2058845B (en) | 1979-08-23 | 1980-08-13 | Method of producing fine metal particles |
| NL8004746A NL8004746A (en) | 1979-08-23 | 1980-08-21 | METHOD FOR THE MANUFACTURE OF FINE METAL PARTICLES |
| DE19803031768 DE3031768A1 (en) | 1979-08-23 | 1980-08-22 | METHOD FOR PRODUCING FINE METAL PARTICLES |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP54107572A JPS5855201B2 (en) | 1979-08-23 | 1979-08-23 | Method for producing metal fine particles |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5633401A JPS5633401A (en) | 1981-04-03 |
| JPS5855201B2 true JPS5855201B2 (en) | 1983-12-08 |
Family
ID=14462565
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP54107572A Expired JPS5855201B2 (en) | 1979-08-23 | 1979-08-23 | Method for producing metal fine particles |
Country Status (4)
| Country | Link |
|---|---|
| JP (1) | JPS5855201B2 (en) |
| DE (1) | DE3031768A1 (en) |
| GB (1) | GB2058845B (en) |
| NL (1) | NL8004746A (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4486225A (en) * | 1982-06-07 | 1984-12-04 | Mpd Technology Corporation | Production of highly reflective metal flake |
| IT1172540B (en) * | 1983-09-07 | 1987-06-18 | Finike Italiana Marposs | FORK COMPARATOR FOR THE CONTROL OF LINEAR DIMENSIONS OF MECHANICAL PIECES |
| JPS6140303A (en) * | 1984-07-31 | 1986-02-26 | Fuji Boseki Kk | Production of low-molecular-weight chitosan |
| JPS6279201A (en) * | 1985-10-01 | 1987-04-11 | Fuji Boseki Kk | Production of porous granular n-acylated chitosan |
| JPH089641B2 (en) * | 1988-05-13 | 1996-01-31 | 大日精化工業株式会社 | Method for producing low molecular weight chitosan |
| JP3884611B2 (en) | 2000-09-13 | 2007-02-21 | 和夫 酒井 | Improving agent for impulsive disease |
| KR20190061828A (en) | 2017-11-27 | 2019-06-05 | 이보균 | Method for producing chitosan for forage use |
-
1979
- 1979-08-23 JP JP54107572A patent/JPS5855201B2/en not_active Expired
-
1980
- 1980-08-13 GB GB8026454A patent/GB2058845B/en not_active Expired
- 1980-08-21 NL NL8004746A patent/NL8004746A/en not_active Application Discontinuation
- 1980-08-22 DE DE19803031768 patent/DE3031768A1/en not_active Withdrawn
Also Published As
| Publication number | Publication date |
|---|---|
| GB2058845B (en) | 1983-09-21 |
| JPS5633401A (en) | 1981-04-03 |
| DE3031768A1 (en) | 1981-03-26 |
| NL8004746A (en) | 1981-02-25 |
| GB2058845A (en) | 1981-04-15 |
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