JPS6242338B2

JPS6242338B2 -

Info

Publication number: JPS6242338B2
Application number: JP56000444A
Authority: JP
Inventors: Akio Ishizawa; Mitsuo Yaegashi; Toshihiko Oguchi; Hirohisa Kato
Original assignee: Tokyo Shibaura Electric Co Ltd
Current assignee: Toshiba Corp
Priority date: 1981-01-07
Filing date: 1981-01-07
Publication date: 1987-09-08
Also published as: JPS57113421A

Description

[Detailed description of the invention]

本発明は磁気記録媒体に関する。磁気記録媒体は一般に磁性粉末と樹脂等より製
造される磁性塗料をポリエステルフイルム等の基
体に種々の方法で塗布したものが一般的である。
又磁性塗料中の磁性粉の分散性を向上させて磁気
特性に関しても配向性（角形比）を良好なものと
するため、界面活性剤が磁性塗料中に添加されて
いる。本発明者等はこの化合物について検討した結
果、および The present invention relates to magnetic recording media. Magnetic recording media are generally made by coating a substrate such as a polyester film with a magnetic paint made of magnetic powder, resin, etc. using various methods.
Furthermore, a surfactant is added to the magnetic paint in order to improve the dispersibility of the magnetic powder in the magnetic paint and to improve the orientation (squareness ratio) in terms of magnetic properties. As a result of studying this compound, the present inventors found that and

【式】（但し、R₁は炭素数８〜20のアルキル基又はアルキル基、ｎは２〜10
の整数）で表わされる化合物（(A)化合物）を使用
すると分散性が良好であり、磁気特性に関しても
配向性がすぐれていることを見い出した。さらに
検討を重ねた結果、R₁は炭素数８〜20のアルキ
ル基又はアルキルフエニール基が、又ｎが２〜10
において特に配向性が良好であることがわかつ
た。しかしながらこれらの化合物の添加量を増大
させるとブリード、ブロツキング等の発生あるい
は塗膜の軟化等の悪影響があることが判明した。
そこで分散性、配向性を阻害しないで耐久性のあ
る塗膜を得るのに鋭意検討した結果、ある種の化
合物を併用することにより解決できた。即ち、[Formula] (where R ₁ is an alkyl group or alkyl group having 8 to 20 carbon atoms, n is 2 to 10
It has been found that the use of a compound (compound (A)) represented by (an integer of ) has good dispersibility and excellent orientation in terms of magnetic properties. As a result of further investigation, R ₁ is an alkyl group having 8 to 20 carbon atoms or an alkyl phenyl group, and n is 2 to 10 carbon atoms.
It was found that the orientation was particularly good. However, it has been found that increasing the amount of these compounds added causes adverse effects such as occurrence of bleeding, blocking, etc., and softening of the coating film.
Therefore, as a result of intensive study to obtain a durable coating film without impairing the dispersibility and orientation, we were able to solve the problem by using a certain type of compound in combination. That is,

【式】【formula】

【式】および[expression] and

【式】（但し、R₂はラウリル、パルミチル、ステアリル、オレイル、セスキオレ
イル等のアルキル基）で表わされる化合物（(B)化
合物）を上記有機リン化合物を組み合せて用いる
ことで分散性、配向性は勿論、耐久性のある塗膜
が得られることがわかつた。本発明では、(A)化合物と(B)化合物の混合比は、
５〜１が好ましい。また、(A)化合物と(B)化合物の
添加量は、磁性粉末100重量部に対して2.0〜6.0
重量部が好ましい。以下実施例を示す。[Formula] (where R ₂ is an alkyl group such as lauryl, palmityl, stearyl, oleyl, sesquioleyl, etc.) (compound (B)) can be used in combination with the above organic phosphorus compounds to improve dispersibility and orientation. It was found that a durable coating film could be obtained. In the present invention, the mixing ratio of compound (A) and compound (B) is
5 to 1 is preferred. The amount of compound (A) and compound (B) added is 2.0 to 6.0 parts by weight per 100 parts by weight of magnetic powder.
Parts by weight are preferred. Examples are shown below.

【表】【table】

【表】以上実施例１〜３および比較例においてこれら
の組成により公知の方法で磁気記録媒体を作成し
た。第１図は実施例においてｎを９一定とし、有機
リン化合物の炭素数を変えたときの配向性（角形
比）の変化を示す。これより炭素数８から20の間
が良好であることがわかる。第２図は有機リン化
合物の炭素数を９一定とし、ｎを変えたときの配
向性の変化を示し、これによりｎが２から10の間
が良好であることがわかる。第３図は(B)化合物界
面活性剤の最適添加量を示したものである。これ
により(A)化合物と(B)化合物の界面活性剤の混合比
は５〜１の間にあることがわかつた。また、第４
図から磁性粉末100重量部に対して本発明の添加
剤を2.0〜6.0重量部添加したときにプリード、ブ
ロツキングがなく、分散性、配向性が阻害される
ことのない耐久性のある塗膜が得られることがわ
かつた。表−１は各実施例と比較例において角形比と摩
耗量（106時間相対速度4.7ｍ／sec）を測定した
結果である。表−１にみられるように本発明によれば、磁気
記録体として角形比を損うことなく摩耗量を大幅
に改善することができた。以上、実施例においては、上記一般式における
R₁として、ノニルフエニル基、トリデシル基の
例を、ｎの値として４、５および９の例を、また
R₂としてオレイル基、パルミチル基、ステアリ
ル基の例をそれぞれ示したが、本発明における他
の化合物においてもこれらと同等の効果を示す。[Table] In Examples 1 to 3 and Comparative Examples, magnetic recording media were prepared using these compositions by a known method. FIG. 1 shows the change in orientation (squareness ratio) when the number of carbon atoms in the organic phosphorus compound was changed with n constant at 9 in the example. From this, it can be seen that a carbon number between 8 and 20 is favorable. FIG. 2 shows the change in orientation when n is changed with the number of carbon atoms in the organic phosphorus compound being constant at 9, and it can be seen from this that n is good when n is between 2 and 10. FIG. 3 shows the optimum amount of compound surfactant (B) added. This revealed that the mixing ratio of the surfactants of compound (A) and compound (B) was between 5 and 1. Also, the fourth
The figure shows that when 2.0 to 6.0 parts by weight of the additive of the present invention is added to 100 parts by weight of magnetic powder, a durable coating film is formed that does not lead or block and does not inhibit dispersibility or orientation. I found out what I could get. Table 1 shows the results of measuring the squareness ratio and amount of wear (relative velocity 4.7 m/sec for 106 hours) in each Example and Comparative Example. As shown in Table 1, according to the present invention, it was possible to significantly improve the amount of wear as a magnetic recording medium without impairing the squareness ratio. As mentioned above, in the examples, in the above general formula,
Examples of nonylphenyl group and tridecyl group as R ₁ , examples of 4, 5 and 9 as the value of n, and
Although examples of oleyl group, palmityl group, and stearyl group are shown as R ₂ , other compounds in the present invention also exhibit effects equivalent to these.

[Brief explanation of the drawing]

第１図、第２図は、本発明において用いる有機
リン化合物の最適な範囲を示す図であり、第３図
は、有機リン化合物と複素環化合物との配合割合
が及ぼす結果を示す図であり、また第４図は本発
明の分散剤の添加量が及ぼす効果を示す図であ
る。 Figures 1 and 2 are diagrams showing the optimal range of the organic phosphorus compound used in the present invention, and Figure 3 is a diagram showing the results of the blending ratio of the organic phosphorus compound and the heterocyclic compound. , and FIG. 4 is a diagram showing the effect of the added amount of the dispersant of the present invention.

【table】

Claims

[Claims] 1 and One or more of the compounds represented by and A magnetic recording material containing one or more of the compounds represented by: [However, R ₁ is an alkyl group or an alkyl phenyl group having 8 to 20 carbon atoms, R ₂ is an alkyl group such as lauryl, palmityl, stearyl, oleyl, sesquioleyl, and n is an integer of 2 to 10. ]