JPH04196503A - Manufacture of magnetic powder having uniform coercive force - Google Patents
Manufacture of magnetic powder having uniform coercive forceInfo
- Publication number
- JPH04196503A JPH04196503A JP2328255A JP32825590A JPH04196503A JP H04196503 A JPH04196503 A JP H04196503A JP 2328255 A JP2328255 A JP 2328255A JP 32825590 A JP32825590 A JP 32825590A JP H04196503 A JPH04196503 A JP H04196503A
- Authority
- JP
- Japan
- Prior art keywords
- powder
- coercive force
- magnetic
- powders
- magnetic powder
- 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.)
- Pending
Links
- 239000006247 magnetic powder Substances 0.000 title claims abstract description 24
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 6
- 239000000843 powder Substances 0.000 claims abstract description 77
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 claims abstract description 13
- 229910052751 metal Inorganic materials 0.000 claims abstract description 12
- 239000002184 metal Substances 0.000 claims abstract description 12
- 238000010438 heat treatment Methods 0.000 claims abstract description 10
- 238000006243 chemical reaction Methods 0.000 claims abstract description 9
- 229910044991 metal oxide Inorganic materials 0.000 claims abstract description 8
- 150000004706 metal oxides Chemical class 0.000 claims abstract description 8
- 239000011812 mixed powder Substances 0.000 claims abstract description 5
- 230000001590 oxidative effect Effects 0.000 claims abstract description 4
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 claims description 16
- 239000002994 raw material Substances 0.000 claims description 12
- 238000002156 mixing Methods 0.000 claims description 8
- WGLPBDUCMAPZCE-UHFFFAOYSA-N Trioxochromium Chemical compound O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 claims description 3
- 229910000423 chromium oxide Inorganic materials 0.000 claims description 3
- 229910052733 gallium Inorganic materials 0.000 claims description 2
- 229910052782 aluminium Inorganic materials 0.000 claims 2
- 150000004649 carbonic acid derivatives Chemical class 0.000 claims 1
- QDOXWKRWXJOMAK-UHFFFAOYSA-N dichromium trioxide Chemical compound O=[Cr]O[Cr]=O QDOXWKRWXJOMAK-UHFFFAOYSA-N 0.000 abstract description 11
- 238000000034 method Methods 0.000 abstract description 11
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 abstract description 4
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 abstract description 4
- 239000000203 mixture Substances 0.000 abstract description 4
- 229910000003 Lead carbonate Inorganic materials 0.000 abstract description 2
- 229910000019 calcium carbonate Inorganic materials 0.000 abstract description 2
- 235000010216 calcium carbonate Nutrition 0.000 abstract description 2
- QZQVBEXLDFYHSR-UHFFFAOYSA-N gallium(III) oxide Inorganic materials O=[Ga]O[Ga]=O QZQVBEXLDFYHSR-UHFFFAOYSA-N 0.000 abstract description 2
- AYJRCSIUFZENHW-UHFFFAOYSA-L barium carbonate Chemical compound [Ba+2].[O-]C([O-])=O AYJRCSIUFZENHW-UHFFFAOYSA-L 0.000 abstract 2
- 239000000463 material Substances 0.000 abstract 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 abstract 1
- 238000013329 compounding Methods 0.000 abstract 1
- 229910052593 corundum Inorganic materials 0.000 abstract 1
- 229910000018 strontium carbonate Inorganic materials 0.000 abstract 1
- LEDMRZGFZIAGGB-UHFFFAOYSA-L strontium carbonate Chemical compound [Sr+2].[O-]C([O-])=O LEDMRZGFZIAGGB-UHFFFAOYSA-L 0.000 abstract 1
- 229910001845 yogo sapphire Inorganic materials 0.000 abstract 1
- 230000000694 effects Effects 0.000 description 6
- 238000010298 pulverizing process Methods 0.000 description 6
- 238000007796 conventional method Methods 0.000 description 5
- 229910000859 α-Fe Inorganic materials 0.000 description 5
- 230000004907 flux Effects 0.000 description 4
- 238000002844 melting Methods 0.000 description 4
- 230000008018 melting Effects 0.000 description 4
- 238000012733 comparative method Methods 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- 108091006629 SLC13A2 Proteins 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 229910052745 lead Inorganic materials 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
Landscapes
- Compounds Of Iron (AREA)
- Hard Magnetic Materials (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
この発明は、保磁力の粉末相互のバラツキが小さく、安
定した磁気特性を示す磁性粉末の製造法に関するもので
ある。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for producing magnetic powder that exhibits stable magnetic properties with small variations in coercive force between powders.
従来、磁気カートや磁気テープなどの磁気記録媒体とし
て用いられている磁性粉末が、例えば特開平２−８６９
０２号公報に記載される方法によって製造されているこ
とは良く知られている。Magnetic powders conventionally used as magnetic recording media such as magnetic carts and magnetic tapes have been disclosed in Japanese Patent Application Laid-Open No. 2-869, for example.
It is well known that it is produced by the method described in No. 02.
この従来方法は、原料粉末として、酸化鉄（以下、Ｆ
ｅ ２０３で示す）粉末、Ｂａ、Ｓｒ。This conventional method uses iron oxide (hereinafter referred to as F) as a raw material powder.
e 203) powder, Ba, Sr.
ｐｂ、およびＣａの炭酸塩（以下、ＢａＣＯ２゜Ｓ ｒ
ｃｏ３．ＰｂＣＯ３，お、Ｊ：びｃａｃｏ３で示す）の
うちの１種以上からなる金属炭酸塩粉末、八ρおよびＧ
ａの酸化物（以下、Ａｇ２Ｏ３，およびＧ ａ ２−０
３で示す）のうちの１種以上からなる金属酸化物粉末、
並びにＮａＣΩ、 Ｂ ａ ＣＤ ２ 。pb, and Ca carbonate (hereinafter referred to as BaCO2°S r
co3. Metal carbonate powder consisting of one or more of PbCO3, O, J: and caco3), 8ρ and G
oxide of a (hereinafter referred to as Ag2O3, and Ga 2-0
metal oxide powder consisting of one or more of the following:
and NaCΩ, B a CD 2 .
ＫＣＩ、およびＳ ｒ Ｃ１２のうちの１種以上からな
る融剤を用い、これら原料粉末を、所定の割合に配合し
、混合した後、この混合粉末を、酸化性雰囲気（大気）
中、９００〜１ＩｏＯ℃の温度に所定時間保持、
の条件で加熱溶解し、冷却し、粉砕し、洗浄して融剤を
除去した後、ろ過し、乾燥することにより磁性粉末を製
造するものである。Using a flux consisting of one or more of KCI and S r C12, these raw material powders are blended in a predetermined ratio and mixed, and then the mixed powder is placed in an oxidizing atmosphere (atmosphere).
Magnetic powder is manufactured by heating and melting the powder at a temperature of 900 to 1 IoO°C for a predetermined period of time, cooling it, pulverizing it, washing it to remove the flux, filtering it, and drying it. be.
一方、近年の磁気カードおよび磁気テープなどにおける
磁気記録の高密度化に伴ない、これに使用される磁性粉
末の保磁力の粉末相互のバラツキか小さく、個々の粉末
かてきるたけ同水準の均一な保磁力を有することか強く
要求される傾向にあるか、上記の従来方法はしめ、その
他の方法で製造された磁性粉末は、高い保磁力をもつも
のの、粉末相互の保磁力のバラツキが相対的に大きく、
これらの要求に十分満足して対応することがてきないの
が現状である。On the other hand, with the recent increase in the density of magnetic recording in magnetic cards and magnetic tapes, the variation in coercive force of the magnetic powder used for this has become smaller, and the coercive force of individual powders has become uniform at the same level. Although magnetic powders produced by the conventional methods mentioned above and other methods have a high coercive force, the variation in coercive force between powders is relatively high. greatly,
At present, it is not possible to meet these demands satisfactorily.
そこで、本発明者等は、上述のような観点から、粉末相
互の保磁力のバラツキか小さ（、かつ高い保磁力を有す
る磁性粉末を製造すべく研究を行なった結果、上記の従
来磁性粉末の製造法で原料粉末として用いられている融
剤を用いず、すなわち加熱融解処理法を適用せずに、加
熱反応処理法を用い、かつ原料粉末として、さらに全体
に占める割合で３〜１０重量％の酸化クロム（以下、Ｃ
ｒ２Ｏ３で示す）粉末を配合すると、製造された磁性粉
末は、高保磁力を保持した状態で、粉末相互のバラツキ
かきわめて小さく、均一な保磁力をもつようになるとい
う研究結果を得たのである。Therefore, from the above-mentioned viewpoint, the present inventors conducted research in order to manufacture a magnetic powder with a small variation in coercive force between powders (and a high coercive force). The heating reaction treatment method is used without using the flux used as the raw material powder in the manufacturing method, that is, without applying the heat melting treatment method, and as the raw material powder, it is further 3 to 10% by weight relative to the total. Chromium oxide (hereinafter referred to as C
The research results showed that when powders (represented by r2O3) are blended, the produced magnetic powder has a uniform coercive force with extremely small variations among the powders while maintaining a high coercive force.
この発明は、上記の研究結果にもとづいてなされたしの
であって、
原料粉末として、Ｆｅ Ｏ粉末と、Ｂ ａ ＣＯａ
。This invention has been made based on the above research results, and uses FeO powder and B a COa as raw material powders.
.
ＳｒＣＯ、ＰｂＣ０、およびＣａ ＣＯ３のうちの１種
以上からなる金属炭酸塩粉末と、Ａｇ２Ｏ３およびＧａ
２Ｏ３のうちの１種以上からなる金属酸化物粉末と、Ｃ
「２０３粉末とを用い、これら原料粉末を、重量％で（
以下％は重量％を示す）金属炭酸塩粉末、１０〜２０％
、
金属酸化物粉末 １５〜４０％、
Ｃ「２０３，３〜ｌＯ％、
Ｆｅ２Ｏ３：残り（たたし、４０〜７０％含有）、から
なる組成に配合し、混合した後、この混合粉末に、
酸化性雰囲気（通常大気）中、９５０〜１２００”Ｃの
温度に所定時間保持、
の条件での加熱反応処理を１回以上施すことにより保磁
力のバラツキの小さい、均一な磁性粉末を製造する方法
に特徴を有するしのである。Metal carbonate powder consisting of one or more of SrCO, PbC0, and CaCO3, and Ag2O3 and Ga
A metal oxide powder consisting of one or more of 2O3 and C
203 powder and these raw material powders in weight% (
% below indicates weight %) Metal carbonate powder, 10-20%
, metal oxide powder 15-40%, C'203,3-10%, Fe2O3: balance (contains 40-70%), and after mixing, to this mixed powder, A method of producing uniform magnetic powder with small variations in coercive force by performing a heating reaction treatment at least once under the conditions of holding at a temperature of 950 to 1200"C for a predetermined time in an oxidizing atmosphere (usually air). Shino has the following characteristics.
つぎに、この発明の方法において、配合組成および加熱
反応処理温度を上記の通りに限定した理由を説明する。Next, in the method of this invention, the reason why the blending composition and heating reaction treatment temperature are limited as described above will be explained.
（ａ） 酸化鉄粉末および金属炭酸塩粉末これらの粉
末には、加熱反応処理で、代表組成かＭ Ｏ−ｎ Ｆ
ｅ ２０３（たたしＭ：Ｂａ、Ｓｒ。(a) Iron oxide powder and metal carbonate powder These powders are heated to give a typical composition or M O-n F
e 203 (Tatashi M: Ba, Sr.
Ｐｂ、およびＣａのうち１種以上）からなるフェライト
磁性粉末を合成するのに不可欠の原料粉末であり、した
かって、その割合が、酸化鉄粉末：４０％未満および金
属炭酸塩粉末５１０％未満ても、また酸化鉄粉末・７０
％および金属炭酸塩粉末：２０％をそれぞれ越えても上
記の組成式を満足せす、これ結果磁性粉末の形成か不可
能となることから、その割合を、それぞれ酸化鉄粉末
４０〜７０％、金属炭酸塩粉末、１０〜２０％とそれぞ
れ定めた。It is an essential raw material powder for synthesizing ferrite magnetic powder consisting of one or more of Pb and Ca), and its proportions are less than 40% for iron oxide powder and less than 510% for metal carbonate powder. Also, iron oxide powder・70
% and metal carbonate powder: Since the above compositional formula is satisfied even if it exceeds 20%, it is impossible to form a magnetic powder, so the proportions are changed to iron oxide powder, respectively.
40-70%, metal carbonate powder, and 10-20%, respectively.
（ｂ） 金属酸化物粉末
これらの粉末には、加熱反応処理後、代表組成式： Ｍ
Ｏ・ｎ （Ｆｅ 、Ａｇ／Ｇａ）２０３を有するフェラ
イト磁性粉末の構成成分として存在し、粉末の保磁力を
向上させる作用があるが、その割合が１５％未満では所
望の保磁力向上効果が得られず、一方その割合か４０９
６を越えると、保磁力に低下傾向か現われるようになる
ことから、その割合を１５〜４０％と定めた。(b) Metal oxide powders These powders, after heating reaction treatment, have a representative compositional formula: M
It exists as a component of ferrite magnetic powder having O.n (Fe, Ag/Ga)203, and has the effect of improving the coercive force of the powder, but if its proportion is less than 15%, the desired coercive force improving effect is not achieved. On the other hand, the percentage is 409
If it exceeds 6, the coercive force tends to decrease, so the ratio was set at 15 to 40%.
（ｃ） Ｃｒ ２０３粉末
Ｃｒ２Ｏ３粉末には、同様に代表組成式・ＭＯ−ｎ （
Ｆｅ 、ＡＮ ／Ｇａ 、Ｃｒ）２０３を有するフェラ
イト磁性粉末の構成成分として存在し、粉末のもつ保磁
力の相互バラツキを小さくし、もって均一な保磁力をも
つようにする作用かあるが、その割合か３％未満ては前
記作用に所望の効果が得られず、一方その割合か１０９
６を越えると保磁力か低下するようになることから、そ
の割合を３〜１０％と定めた。(c) Cr203 powder Cr2O3 powder has a representative compositional formula MO-n (
Fe, AN/Ga, Cr) 203 exists as a component of ferrite magnetic powder, and has the effect of reducing the mutual variation in the coercive force of the powder and making it have a uniform coercive force, but the proportion If the ratio is less than 3%, the desired effect cannot be obtained;
If it exceeds 6, the coercive force will decrease, so the ratio was set at 3 to 10%.
（ｄ） 加熱反応処理温度
その温度か９５０℃未満では、フェライトへの合成反応
か遅く、実操業的でなく、一方その温度か１２００℃を
越えると、合成後のフェライト粉末に融着が起こるよう
になり、処理後の粉砕が困難になるばかりでなく、結晶
粒か粗大化して保磁力が低下するようになることから、
その温度を９５０〜１２００℃に定めた。(d) Heating reaction treatment temperature If the temperature is lower than 950°C, the synthesis reaction to ferrite will be slow and not suitable for practical operation, while if the temperature exceeds 1200°C, fusion will occur in the ferrite powder after synthesis. This not only makes pulverization difficult after treatment, but also causes the crystal grains to become coarser and reduce the coercive force.
The temperature was set at 950-1200°C.
つぎに、この発明の方法を実施例により具体的に説明す
る。Next, the method of the present invention will be specifically explained using examples.
原料粉末として、Ｆｅ２Ｏ３粉末、各種の金属炭酸塩粉
末、ＡΩ２０３粉末、Ｇａ２Ｏ３粉末、およびＣｒ２Ｏ
３粉末を用意し、さらに融剤としてＮａＣ１粉末および
Ｂ ａ Ｃｉ’ ２粉末も用い、これら原料粉末を第１
表に示される割合に配合し、ボールミルで２４時間粉砕
混合した後、同じく第１表に示される条件で加熱反応処
理（２回以上の場合は１回毎に微粉砕を行なう）または
加熱融解処理を行ない、処理後ボールミルで１０時間の
粉砕を行なうことにより本発明法１〜７、比較法１〜３
、および従来法１〜４をそれぞれ実施し、磁性粉末を製
造した。Raw material powders include Fe2O3 powder, various metal carbonate powders, AΩ203 powder, Ga2O3 powder, and Cr2O.
3 powders were prepared, NaC1 powder and B a Ci' 2 powder were also used as fluxing agents, and these raw material powders were
After blending in the proportions shown in the table and pulverizing and mixing in a ball mill for 24 hours, heat reaction treatment (if pulverization is performed twice or more, finely pulverize each time) or heat melting treatment under the conditions also shown in Table 1. After the treatment, pulverization was carried out in a ball mill for 10 hours to obtain methods 1 to 7 of the present invention and comparative methods 1 to 3.
, and Conventional Methods 1 to 4 were carried out, respectively, to produce magnetic powder.
なお、従来法１〜４においては、加熱融解処理後の粉砕
に引続いて、洗浄、ろ過、および乾燥の融剤除去処理を
施した。In Conventional Methods 1 to 4, subsequent to the pulverization after the heating and melting treatment, flux removal treatment of washing, filtration, and drying was performed.
また、比較法１〜３は、いずれも原料粉末としてＣｒ２
Ｏ３粉末を配合しない場合、並びに配合してもその割合
がこの発明の範囲から外れた場合を示すものである。In addition, Comparative Methods 1 to 3 all use Cr2 as the raw material powder.
This shows the case where O3 powder is not blended, and the case where even if O3 powder is blended, the proportion is outside the scope of the present invention.
この結果得られた各種の磁性粉末について、ロット毎に
任意の５個所から試料を取り出し、それぞれの粉末試料
の保磁力をＭ］定し、第１表に保磁力のバラツキを評価
する目的で、最高値と最低値を示した。また、第１表に
は磁性粉末の組成も示した。For the various magnetic powders obtained as a result, samples were taken from five arbitrary locations for each lot, and the coercive force of each powder sample was determined. Highest and lowest values were shown. Table 1 also shows the composition of the magnetic powder.
第１表に示される結果から、本発明法１〜７によれば、
いずれも従来法１〜４で製造された磁性粉末と同等の高
保磁力を有し、かつこれより一段と保磁力の粉末相互の
バラツキかきわめて小さい磁性粉末を製造することかで
き、また、比較法１〜３に見られるように、Ｃｒ２Ｏ３
粉末の配合割合かこの発明の範囲から低い方に外れる（
配合しない場合も含む）と、保磁力のバラツキか大きく
なり、一方Ｃｒ２Ｏ３粉末の配合割合がこの発明の範囲
から外れて多くなると保磁力が低下するようになること
が明らかである。From the results shown in Table 1, according to methods 1 to 7 of the present invention,
All of them can produce magnetic powders that have a high coercive force equivalent to that of the magnetic powders produced by conventional methods 1 to 4, and have much smaller variations in coercive force among the powders. As seen in ~3, Cr2O3
The blending ratio of powder is lower than the scope of this invention (
It is clear that if the blending ratio of Cr2O3 powder exceeds the scope of the present invention and increases, the coercive force will decrease.
上述のように、この発明の方法によれば、保磁力の粉末
相互のバラツキがきわめて小さく、均一な保磁力をもっ
た磁性粉末を製造することができ、しかもこの結果再ら
れた磁性粉末は高い保磁力を合せもつので、これを磁気
カードや磁気テープなどの磁気記録媒体として用いた場
合、磁気記録を安定した状態で高密度化できるなど工業
上有用な効果をもたらすのである。As described above, according to the method of the present invention, it is possible to produce magnetic powder with extremely small variations in coercive force between powders and a uniform coercive force, and the resulting recycled magnetic powder has a high Since it also has a coercive force, when used as a magnetic recording medium such as a magnetic card or magnetic tape, it brings about industrially useful effects such as stably increasing the density of magnetic recording.
Claims (1)
ｂ．およびＣａの炭酸塩のうちの１種以上からなる金属
炭酸塩粉末と、ＡｌおよびＧａの酸化物のうちの１種以
上からなる金属酸化物粉末と、酸化クロム粉末とを用い
、これら原料粉末を、重量％で、 金属炭酸塩粉末：１０〜２０％、 金属酸化物粉末：１５〜４０％、 酸化クロム粉末：３〜１０％、 酸化鉄粉末：残り（ただし４０〜７０％含有）、からな
る配合組成に配合し、混合した後、この混合粉末に、 酸化性雰囲気中、９５０〜１２００℃の温度に所定時間
保持、 の条件での加熱反応処理を１回以上施すことを特徴とす
る均一な保磁力を有する磁性粉末の製造法。(1) Iron oxide powder, Ba, Sr, P as raw material powder
b. A metal carbonate powder consisting of one or more of carbonates of Al and Ca, a metal oxide powder consisting of one or more of oxides of Al and Ga, and a chromium oxide powder are used to prepare these raw material powders. , in weight%, consists of: metal carbonate powder: 10-20%, metal oxide powder: 15-40%, chromium oxide powder: 3-10%, iron oxide powder: remainder (contains 40-70%). After blending and mixing, the mixed powder is subjected to a heating reaction treatment at least once under the conditions of holding at a temperature of 950 to 1200°C for a predetermined time in an oxidizing atmosphere. A method for producing magnetic powder with coercive force.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2328255A JPH04196503A (en) | 1990-11-28 | 1990-11-28 | Manufacture of magnetic powder having uniform coercive force |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2328255A JPH04196503A (en) | 1990-11-28 | 1990-11-28 | Manufacture of magnetic powder having uniform coercive force |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04196503A true JPH04196503A (en) | 1992-07-16 |
Family
ID=18208178
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2328255A Pending JPH04196503A (en) | 1990-11-28 | 1990-11-28 | Manufacture of magnetic powder having uniform coercive force |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04196503A (en) |
-
1990
- 1990-11-28 JP JP2328255A patent/JPH04196503A/en active Pending
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