JPS63299203A - Surface treatment of magnetic metal powder - Google Patents
Surface treatment of magnetic metal powderInfo
- Publication number
- JPS63299203A JPS63299203A JP62131687A JP13168787A JPS63299203A JP S63299203 A JPS63299203 A JP S63299203A JP 62131687 A JP62131687 A JP 62131687A JP 13168787 A JP13168787 A JP 13168787A JP S63299203 A JPS63299203 A JP S63299203A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic metal
- metal powder
- surface treatment
- isocyanic ester
- treatment
- 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
- 239000002184 metal Substances 0.000 title claims abstract description 57
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 57
- 239000000843 powder Substances 0.000 title claims abstract description 56
- 238000004381 surface treatment Methods 0.000 title claims abstract description 22
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 22
- -1 ester compound Chemical class 0.000 claims abstract description 22
- 239000007788 liquid Substances 0.000 claims abstract description 13
- 229910052742 iron Inorganic materials 0.000 claims abstract description 11
- 125000001931 aliphatic group Chemical group 0.000 claims abstract description 9
- 239000002635 aromatic organic solvent Substances 0.000 claims abstract description 5
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract 3
- 229910052799 carbon Inorganic materials 0.000 claims abstract 3
- 238000000034 method Methods 0.000 claims description 16
- 239000012948 isocyanate Substances 0.000 claims description 15
- 125000004432 carbon atom Chemical group C* 0.000 claims description 4
- 239000007789 gas Substances 0.000 claims description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 3
- 229910052760 oxygen Inorganic materials 0.000 claims description 3
- 239000001301 oxygen Substances 0.000 claims description 3
- 238000001704 evaporation Methods 0.000 claims description 2
- 239000006185 dispersion Substances 0.000 abstract description 4
- 150000002148 esters Chemical class 0.000 abstract 3
- 230000003064 anti-oxidating effect Effects 0.000 abstract 2
- 125000000113 cyclohexyl group Chemical group [H]C1([H])C([H])([H])C([H])([H])C([H])(*)C([H])([H])C1([H])[H] 0.000 abstract 1
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 21
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 8
- 230000003647 oxidation Effects 0.000 description 7
- 238000007254 oxidation reaction Methods 0.000 description 7
- 230000000052 comparative effect Effects 0.000 description 6
- 239000006247 magnetic powder Substances 0.000 description 6
- 230000015572 biosynthetic process Effects 0.000 description 5
- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 description 3
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 238000007796 conventional method Methods 0.000 description 3
- 230000005415 magnetization Effects 0.000 description 3
- 239000002904 solvent Substances 0.000 description 3
- KQWGXHWJMSMDJJ-UHFFFAOYSA-N cyclohexyl isocyanate Chemical compound O=C=NC1CCCCC1 KQWGXHWJMSMDJJ-UHFFFAOYSA-N 0.000 description 2
- 230000006866 deterioration Effects 0.000 description 2
- 235000014113 dietary fatty acids Nutrition 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 229930195729 fatty acid Natural products 0.000 description 2
- 239000000194 fatty acid Substances 0.000 description 2
- 150000004665 fatty acids Chemical class 0.000 description 2
- 239000003960 organic solvent Substances 0.000 description 2
- 239000003973 paint Substances 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- YIDSTEJLDQMWBR-UHFFFAOYSA-N 1-isocyanatododecane Chemical compound CCCCCCCCCCCCN=C=O YIDSTEJLDQMWBR-UHFFFAOYSA-N 0.000 description 1
- QWDQYHPOSSHSAW-UHFFFAOYSA-N 1-isocyanatooctadecane Chemical compound CCCCCCCCCCCCCCCCCCN=C=O QWDQYHPOSSHSAW-UHFFFAOYSA-N 0.000 description 1
- 229920002799 BoPET Polymers 0.000 description 1
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 description 1
- 235000021355 Stearic acid Nutrition 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 229920001577 copolymer Polymers 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- QIQXTHQIDYTFRH-UHFFFAOYSA-N octadecanoic acid Chemical compound CCCCCCCCCCCCCCCCCC(O)=O QIQXTHQIDYTFRH-UHFFFAOYSA-N 0.000 description 1
- OQCDKBAXFALNLD-UHFFFAOYSA-N octadecanoic acid Natural products CCCCCCCC(C)CCCCCCCCC(O)=O OQCDKBAXFALNLD-UHFFFAOYSA-N 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 229920005749 polyurethane resin Polymers 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 239000008117 stearic acid Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 239000008096 xylene Substances 0.000 description 1
- 229910052725 zinc Inorganic materials 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
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Paints Or Removers (AREA)
- Powder Metallurgy (AREA)
- Magnetic Record Carriers (AREA)
- Manufacturing Of Magnetic Record Carriers (AREA)
- Hard Magnetic Materials (AREA)
Abstract
Description
【発明の詳細な説明】
〈産業上の利用分舒〉
本発明は、磁性金属粉末の耐酸化性及び分散性を向上さ
せるための磁性金属粉末の表面処理法に関する。DETAILED DESCRIPTION OF THE INVENTION <Industrial Application> The present invention relates to a method for surface treatment of magnetic metal powder to improve its oxidation resistance and dispersibility.
〈従来の技術〉
従来、オーディオテープ、ビデオテープなどの磁気テー
プ等の磁性粉末としては主に酸化鉄系磁性粉末が用いら
れていたが、近年、磁気テープの高性能化の要求に対応
するために鉄又は鉄を主体とする磁性金属粉末が用いら
れるようになってきた。しかし、この磁性金属粉末は、
従来の酸化鉄系磁性粉末と比較した場合優れた磁性特性
を有しているが、金属粉であるため化学的に不安定であ
るという欠点を有している。すなわち、磁性金属粉末は
空気中にて酸化され易いので場合によっては発火の危険
があるとともに、得られた磁気テープ等の磁気特性が経
時的に低下してしまうという問題がある。又、磁性金属
粉末は酸化鉄系磁性粉末と較べて凝集し易いので、例え
ば磁気テープ製造における塗料化の際に分散性が悪いと
いう問題がある。<Conventional technology> In the past, iron oxide-based magnetic powders were mainly used as magnetic powders for magnetic tapes such as audio tapes and video tapes, but in recent years, in order to meet the demands for higher performance of magnetic tapes, iron oxide magnetic powders have been used. Iron or magnetic metal powders mainly composed of iron have come to be used. However, this magnetic metal powder
Although it has superior magnetic properties when compared to conventional iron oxide magnetic powder, it has the disadvantage of being chemically unstable because it is a metal powder. That is, since magnetic metal powder is easily oxidized in the air, there is a risk of ignition in some cases, and there is a problem that the magnetic properties of the obtained magnetic tape etc. deteriorate over time. Furthermore, since magnetic metal powders tend to aggregate more easily than iron oxide magnetic powders, there is a problem in that they have poor dispersibility when, for example, they are made into paints in the manufacture of magnetic tapes.
そこで、従来においては発火を防止し且つ安定化するた
めに磁性金属粉末を気相あるいは液相にて徐々に酸化し
て粒子表面に緻密な酸化皮膜を形成しており、さらに耐
酸化性を高めるとともに分散性を向上させるための表面
処理法が種々検討されている。例えば、特開昭４９−９
７７３８号公報には金属磁性粉末と高級脂肪酸粉末とを
有機溶剤中で攪拌混合することにより粒子表面に高級脂
肪酸基膜を形成する方法が開示されている。Therefore, in the past, in order to prevent and stabilize ignition, magnetic metal powder was gradually oxidized in the gas or liquid phase to form a dense oxide film on the particle surface, which further increased the oxidation resistance. At the same time, various surface treatment methods have been studied to improve dispersibility. For example, JP-A-49-9
Japanese Patent No. 7738 discloses a method of forming a higher fatty acid base film on the particle surface by stirring and mixing metal magnetic powder and higher fatty acid powder in an organic solvent.
一方、短波長記録による高記録密度化の流れの中で磁性
金属粉末の微細化が進められているが、磁性金属粉末に
おいては微細になればなるほど酸化され易くなるととも
に分散し２ζくくなるというｒＪＪ題がある。よって、
微細化された磁性金属粉末、例えば比表面８Ｉ５５ｒｎ
’ ／ ｇ以上の高比表面積を有する磁性金属粉末にお
いては上述したような表面処理では対処できないという
のが現状である。On the other hand, with the trend toward higher recording densities through short wavelength recording, magnetic metal powders are being made finer. There is a problem. Therefore,
Finely divided magnetic metal powder, e.g. specific surface 8I55rn
The current situation is that magnetic metal powders having a high specific surface area of 1/g or more cannot be treated with the above-mentioned surface treatment.
本発明はこのような事情に鑑み、高比表面積の磁性金属
粉末に対しても耐酸化性及び分散性の双方を向上させる
ことができる磁性金属粉末の表面処理法を提供すること
を目的とする。In view of these circumstances, an object of the present invention is to provide a surface treatment method for magnetic metal powder that can improve both oxidation resistance and dispersibility even for magnetic metal powder with a high specific surface area. .
く問題点を解決するための手段〉
前記目的を達成する本発明の構成は鉄又は鉄を主体とす
る磁性金属粉末を炭素数６〜８の脂肪族もしくＣよ環状
脂肪族のイソシアン酸エステル化合物で表面処理するこ
とを特徴とする。Means for Solving the Problems> The structure of the present invention to achieve the above object is to mix iron or magnetic metal powder mainly composed of iron with an aliphatic or C-cycloaliphatic isocyanate ester having 6 to 8 carbon atoms. It is characterized by surface treatment with a compound.
本発明では、炭素数６〜８の脂肪族もしくは環状脂肪族
のイソシアン酸エステル化合物（以下「イソシアン酸エ
ステル化合物」という）を用いて常法により磁性金属粉
末の表面処理を行えばいいのであるが、好適にはイソシ
アン酸エステル化合物を芳香族有機溶媒１ζ溶解又は分
散した処理液中に磁性金属粉末を浸漬することによって
行うのがよい。In the present invention, the magnetic metal powder may be surface-treated by a conventional method using an aliphatic or cycloaliphatic isocyanate compound having 6 to 8 carbon atoms (hereinafter referred to as "isocyanate compound"). This is preferably carried out by immersing the magnetic metal powder in a treatment liquid in which an isocyanate ester compound is dissolved or dispersed in an aromatic organic solvent 1ζ.
本発明で用いるイソシアン酸エステル化合物としてはｎ
−オクチルイソシアン酸エステル、ｎ−ドデシルイソシ
アン酸エステル、ｎ−オクタデシルイソシアン酸エステ
ル、シクロヘキシルイソシアン酸エステル等を挙ケるこ
とができる。このイソシアン酸エステル化合物は表面処
理された磁性金属粉末重量に対して０．１〜７！ｉｔ％
、好ましくは３〜５重量％となる量を用いるのがよい。The isocyanate ester compound used in the present invention is n
Examples include -octyl isocyanate, n-dodecyl isocyanate, n-octadecyl isocyanate, and cyclohexyl isocyanate. The amount of this isocyanate ester compound is 0.1 to 7% relative to the weight of the surface-treated magnetic metal powder. it%
, preferably in an amount of 3 to 5% by weight.
これは０．１重量％未満では表面処理効果が不十分であ
り、７重量％を超えて用いても増量効果がみられないか
らである。This is because if the amount is less than 0.1% by weight, the surface treatment effect will be insufficient, and if it is used in excess of 7% by weight, no increase in weight will be achieved.
また、本発明方法が適用できる磁性金属粉末としては鉄
又は鉄を主体としてこれにＮｌ。Further, the magnetic metal powder to which the method of the present invention can be applied is iron or iron as a main component, and Nl is added to the iron.
Ｃｏ、Ｚｎ、Ｍｎ、Ｃｒ、Ｍｇ、Ｐ、Ａｊ、Ｓｉ等を少
なくとも１９１以上添加したものなどがあるが、この磁
性金属粉末は酸化皮膜形成前のものでもよいし、常法に
より全体にあるいは部分的に酸化皮膜を形成したもので
もよい。There are magnetic metal powders containing at least 191 or more elements such as Co, Zn, Mn, Cr, Mg, P, Aj, Si, etc., but this magnetic metal powder may be before the formation of an oxide film, or it may be completely or partially added by a conventional method. A material with an oxide film formed thereon may also be used.
ここで、イソシアン酸エステル化合物を芳香族有機溶媒
に溶解・分散した処理液中に磁性金属粉末を浸漬するこ
とにより行う表面処理法について説明する。Here, a surface treatment method performed by immersing magnetic metal powder in a treatment liquid in which an isocyanate ester compound is dissolved and dispersed in an aromatic organic solvent will be described.
イソシアン酸エステル化合物を溶解・分散するための芳
香＃Ｃ有機溶媒としては例えば、ベンゼン、トルエン、
キシレン等がある。これら溶媒を用いて処理液を調製す
る場合には、イソシアン酸エステル化合物が表面処理さ
れた磁性金属粉末重量に対して上述したように０．１〜
７重量％、好ましくは３〜５重量％となろようにする。Examples of aromatic #C organic solvents for dissolving and dispersing isocyanate ester compounds include benzene, toluene,
There are xylene, etc. When preparing a treatment liquid using these solvents, the amount of isocyanate ester compound is 0.1 to 0.1 to
The amount should be 7% by weight, preferably 3-5% by weight.
この処理液による磁性金属粉末の処理は６０℃以上で行
うのがよい。この処理は０．５〜１０時間、好ましくは
１〜５時間程度浸漬した後磁性金属粉末を取り出して乾
燥することにより行ってもよいし、磁性金属粉末を浸漬
している処理液から溶媒を蒸発・留去し、全て留去した
後取り出すようにしてもよい。The treatment of magnetic metal powder with this treatment liquid is preferably carried out at 60° C. or higher. This treatment may be carried out by immersing the magnetic metal powder for 0.5 to 10 hours, preferably 1 to 5 hours, then taking it out and drying it, or by evaporating the solvent from the treatment liquid in which the magnetic metal powder is immersed. - You may distill it off and take it out after all of it has been distilled off.
さらに、この表面処理法を実施する場合には磁性金属粉
末として酸化膜形成前のものを用い、該磁性金属粉末が
浸漬された処理液に酸素含有ガスを導入することにより
、表面処理及び酸化皮膜形成を同時に行うようにするの
が好適である。Furthermore, when carrying out this surface treatment method, the magnetic metal powder is used before oxide film formation, and by introducing an oxygen-containing gas into the treatment solution in which the magnetic metal powder is immersed, surface treatment and oxide film formation are performed. Preferably, the formation takes place simultaneously.
く実 施 例〉 以下に本発明の実施例を詳細に説明する。Example of implementation Examples of the present invention will be described in detail below.
（実施例１）
■ 表面処理
ｎ−オクタデシルイソシアン酸エステル６０ｇをトルエ
ン３１中に溶解して処理液を調製し、この処理液に酸化
皮膜形成前の磁性金属粉末（長軸０．１５μｍ１軸比７
〜１０、比表面積６０ ｍ’／ ｇ ） １ ｋｇを
浸漬し、−晩装置した。(Example 1) ■ Surface treatment A treatment solution was prepared by dissolving 60 g of n-octadecyl isocyanate ester in 31 toluene, and a magnetic metal powder (major axis: 0.15 μm, uniaxial ratio: 7) before oxide film formation was added to this treatment solution.
~10, specific surface area 60 m'/g) 1 kg was immersed and left overnight.
次にこの浸漬液を内容積２０１のステンレス製密閉容璧
に全量を投入し、内部温度を６０℃に保持しつつ５％酸
素含有ガスを２０！／分の流量で処理液中に導入するこ
とにより磁性金属粉末表面に酸化皮膜を形成した。その
後溶媒を完全に蒸発させて表面処理された磁性金属粉末
を取り出し、乾燥した。Next, the entire amount of this immersion liquid is poured into a stainless steel airtight container with an internal volume of 201°C, and while maintaining the internal temperature at 60°C, 5% oxygen-containing gas is added at 20°C. An oxide film was formed on the surface of the magnetic metal powder by introducing it into the treatment solution at a flow rate of /min. Thereafter, the solvent was completely evaporated and the surface-treated magnetic metal powder was taken out and dried.
この表面処理磁性金属粉末の磁性特性、比表面積及び耐
酸化性を測定した。この結果を第１表に示す。なお、耐
酸化性は表面処理磁性金属粉末を６０℃、９０％ＲＨの
空気中に暴露し、１週間経過後の飽和磁化を測定し、こ
の飽和磁化の暴露前の飽和磁化に対する劣化率（Δσ）
で評価した。The magnetic properties, specific surface area, and oxidation resistance of this surface-treated magnetic metal powder were measured. The results are shown in Table 1. The oxidation resistance is measured by exposing the surface-treated magnetic metal powder to air at 60°C and 90% RH, measuring the saturation magnetization after one week, and calculating the deterioration rate (Δσ) of this saturation magnetization relative to the saturation magnetization before exposure. )
It was evaluated by
■ 磁気シートの作製
上記表面処理磁性金属粉末を用い、下記の組成でサンド
ミルにより分散塗料化した。(2) Preparation of magnetic sheet The surface-treated magnetic metal powder described above was used to form a dispersion coating using a sand mill using the following composition.
表面処理磁性金属粉末 １００ＶＡＧＨ（
塩ビ・酢ビ共重合体）１１
ポリウレタン樹脂 １ルシチン
２メチルエチルケト
ン ８０トルエン
８０シクロへキサノン
４０上述のようにして得た分散塗料をＰＥＴフィル
ム（厚み１０μｍ）上に塗布し、次いで、永久磁石３０
００Ｇにより磁場配向させて乾燥し、磁性塗膜厚みが３
μｍの磁気シートを得た。Surface treatment magnetic metal powder 100VAGH (
PVC/vinyl acetate copolymer) 11 Polyurethane resin 1 Lucitin 2 Methyl ethyl ketone 80 Toluene
80cyclohexanone
40 The dispersion paint obtained as described above was applied onto a PET film (thickness 10 μm), and then a permanent magnet 30
00G magnetic field orientation and drying, the thickness of the magnetic coating is 3.
A μm magnetic sheet was obtained.
得られた磁気シートの磁気特性を第２表に示す。The magnetic properties of the obtained magnetic sheet are shown in Table 2.
（実施例２）
シクロヘキシルイソシアン酸エステル３０呂をトルエン
３Ｉ中に溶解して処理液を調製し、以下実施例１と同様
に操作した。この結果を第１表及び第２表に示す。(Example 2) A treatment liquid was prepared by dissolving 30 parts of cyclohexyl isocyanate in 3 I of toluene, and the same procedure as in Example 1 was carried out. The results are shown in Tables 1 and 2.
（比較例１）
イソシアン酸エステル化合物を添加せず、トルエンだけ
を用いて実施例１と同様の条件で操作した。この結果を
第１表及び第２表に示す。(Comparative Example 1) Operation was carried out under the same conditions as in Example 1 using only toluene without adding an isocyanate ester compound. The results are shown in Tables 1 and 2.
（比較例２）
ステアリン酸４０ｇをトルエン５１中に溶解して処理液
とした他は、実施例１とｒｒＩＪ様に操作した。この結
果を第１表及び第２表に示す。(Comparative Example 2) The procedure of Example 1 and rrIJ was repeated except that 40 g of stearic acid was dissolved in 51 parts of toluene to prepare a treatment liquid. The results are shown in Tables 1 and 2.
第２表
第１表より、実施例１，２による表面処理磁性金属粉末
は比較例１，２のものと比べて劣化率が著しく小さくな
っており、耐酸化性が向上しているのが認められた。ま
た磁気特性においても同等以上の値を示しな。Table 2 From Table 1, it can be seen that the surface-treated magnetic metal powders according to Examples 1 and 2 have significantly lower deterioration rates than those of Comparative Examples 1 and 2, and have improved oxidation resistance. It was done. Also, the magnetic properties should show equivalent or higher values.
また実施例１，２の表面処理磁性金属粉末を用いて作製
した磁気シートにおいては比較例１．２のものに比べて
特に角形比（Ｓｑ）が向上されているのが認められる。Furthermore, it is observed that the magnetic sheets produced using the surface-treated magnetic metal powders of Examples 1 and 2 have particularly improved squareness ratios (Sq) compared to those of Comparative Examples 1.2.
すなわち、実施例１，２においては、空試験となる比較
例１に比べて０．０２〜０．０３改善され、従来法によ
る表面処理を行った比較例２と同等以上の角形比となっ
ているが、これは塗料化の際の分散性が大きく向上して
いることを示している。That is, in Examples 1 and 2, the squareness ratio was improved by 0.02 to 0.03 compared to Comparative Example 1, which was a blank test, and was equal to or higher than Comparative Example 2, which was surface treated by the conventional method. However, this shows that the dispersibility during coating has been greatly improved.
また、実施例１，２の表面処理磁性金属粉末をトルエン
で洗浄してその洗浄液を分析したが、イソシアン酸エス
テル化合物は全く検出されなかった。これにより、磁性
金属粉末の表面においてイソシアン酸エステル化合物が
強固に保持されていることが確認された。Furthermore, when the surface-treated magnetic metal powders of Examples 1 and 2 were washed with toluene and the washing solution was analyzed, no isocyanate compound was detected. This confirmed that the isocyanate ester compound was firmly held on the surface of the magnetic metal powder.
〈発明の効果〉
以上、実施例とともに具体的に説明したように、本発明
方法によれば耐酸化性及び分散性が著しく向上した磁性
金属粉末を得ることができろ。<Effects of the Invention> As specifically explained above in conjunction with Examples, the method of the present invention makes it possible to obtain magnetic metal powder with significantly improved oxidation resistance and dispersibility.
特 許 出 願 人 三井金属鉱業株式会社 代 理 人Patent applicant Mitsui Metal Mining Co., Ltd. People
Claims (6)
８の脂肪族もしくは環状脂肪族のイソシアン酸エステル
化合物で表面処理することを特徴とする磁性金属粉末の
表面処理法。(1) Iron or iron-based magnetic metal powder with a carbon number of 6 or more
8. A method for surface treatment of magnetic metal powder, comprising surface treatment with an aliphatic or cycloaliphatic isocyanate ester compound.
シアン酸エステル化合物を芳香族有機溶媒に溶解又は分
散した処理液に磁性金属粉末を浸漬する特許請求の範囲
第１項記載の磁性金属粉末の表面処理法。(2) The magnetic metal according to claim 1, wherein the magnetic metal powder is immersed in a treatment liquid in which an aliphatic or cycloaliphatic isocyanate compound having 6 to 8 carbon atoms is dissolved or dispersed in an aromatic organic solvent. Powder surface treatment method.
上である特許請求の範囲第２項記載の磁性金属粉末の表
面処理法。(3) The method for surface treatment of magnetic metal powder according to claim 2, wherein the treatment temperature of the magnetic metal powder with the treatment liquid is 60° C. or higher.
上として芳香族有機溶媒を蒸発・留去しながら処理する
特許請求の範囲第２項記載の磁性金属粉末の表面処理法
。(4) The surface treatment method for magnetic metal powder according to claim 2, wherein the magnetic metal powder is treated with the treatment liquid at a treatment temperature of 60° C. or higher while evaporating and distilling off the aromatic organic solvent.
る特許請求の範囲第２項、第３項あるいは第４項記載の
磁性金属粉末の表面処理法。(5) A method for surface treatment of magnetic metal powder according to claim 2, 3 or 4, wherein an oxygen-containing gas is introduced into the treatment liquid during surface treatment.
シアン酸エステル化合物が表面処理された磁性金属粉末
重量に対して０．１〜７重量％である特許請求の範囲第
１項〜第５項の何れかに記載の磁性金属粉末の表面処理
法。(6) Claims 1 to 7 in which the aliphatic or cycloaliphatic isocyanate compound having 6 to 8 carbon atoms is present in an amount of 0.1 to 7% by weight based on the weight of the surface-treated magnetic metal powder. The method for surface treatment of magnetic metal powder according to any one of Item 5.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62131687A JPS63299203A (en) | 1987-05-29 | 1987-05-29 | Surface treatment of magnetic metal powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62131687A JPS63299203A (en) | 1987-05-29 | 1987-05-29 | Surface treatment of magnetic metal powder |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS63299203A true JPS63299203A (en) | 1988-12-06 |
Family
ID=15063867
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62131687A Pending JPS63299203A (en) | 1987-05-29 | 1987-05-29 | Surface treatment of magnetic metal powder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63299203A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1990012392A1 (en) * | 1989-04-05 | 1990-10-18 | Hitachi Maxell Ltd. | Magnetic recording medium |
-
1987
- 1987-05-29 JP JP62131687A patent/JPS63299203A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1990012392A1 (en) * | 1989-04-05 | 1990-10-18 | Hitachi Maxell Ltd. | Magnetic recording medium |
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