JPS5928218A - Magnetic recording medium - Google Patents

Abstract

PURPOSE:To obtain a magnetic recording medium having high electromagnetic conversion characteristics and physical characteristics by using a copolymer consisting of vinyl chloride, vinyl ester of alkylcarboxylic acid, a monomer copolymerizable with vinyl chloride, and a saponification product of vinyl ester of alkylcarboxylic acid as an impregnating agent for nitrocellulose and adding a curing agent to improve the strength of a coated film. CONSTITUTION:For example, 16-40g nitrocellulose impregnated with a quaternary vinyl chloride-vinyl acetate type copolymer [the absorption ratio of OH/CH: 0, 0.2, 0.3, 0.5, 0.7 or 0.9, and the monomer (maleic acid) content: 0, 0.5, 1.0, 1.5, 2.0, 2.5 or 3.0(%)], 6-14g polyurethane resin, 120-200g magnetic powder, and 12-36g curing agent are kneaded with a kneader to mix the nitrocellulose with the copolymer. The weight ratio of the nitrocellulose/the copolymer is 0.6-9. The mixture is formed into a resin sheet with a heat roll at 30-40 deg.C while evaporating the solvent, and the residual solvent is evaporated at room temp. The resulting sheet is crushed to form chips.

Description

【発明の詳細な説明】 本発明は磁気記録媒体に関する。[Detailed description of the invention] The present invention relates to magnetic recording media.

磁気テープの結合材に硝化綿は、ゴム系バインダと組合
せて広く用いられている。これは硝化綿のもつ磁性粉と
の親和性・力学的強度が磁気テープのすぐれた電磁特性
・物理特性として反訣される事による。Nitrified cotton is widely used as a binding material for magnetic tape in combination with a rubber binder. This is because the affinity with magnetic powder and mechanical strength of nitrified cotton are used as the excellent electromagnetic and physical properties of magnetic tape.

硝化綿を用いる磁気記録媒体の具体例は特公昭４Ｂ−３
１６０５、同４９−４８１２６号、同５４−２９０８５
号、同５４−１９００９を等に記載されている。A specific example of a magnetic recording medium using nitrified cotton is published in Tokuko Sho 4B-3.
1605, No. 49-48126, No. 54-29085
No. 54-19009, etc.

しかし硝化綿は反応性が高く、発火性を有する危険物で
あり単独で保存・静置するに適さない。However, nitrified cotton is highly reactive and flammable, making it a dangerous substance that is not suitable for storage or standing alone.

安全性を高めるために、含浸剤により浸潤処理を施すの
であるが、含浸剤としてはイソプロピルアルコールやジ
ブチルフタレートなどが用いられていた。しかし、これ
らの添加によって、磁気記録媒体の結合剤としての硝化
綿の特性は低下するのをまぬがれ得ず、前者に於いては
硬化剤と共に使用した場合の不具合、また後者に於いて
は、走行特性・耐久性などの物理特性が可塑剤としての
ジブチル７タレートのために犠牲になっていた。In order to increase safety, an infiltration treatment is performed using an impregnating agent, and as the impregnating agent, isopropyl alcohol, dibutyl phthalate, etc. have been used. However, these additions inevitably reduce the properties of nitrified cotton as a binder for magnetic recording media, and the former may cause problems when used with a hardening agent, and the latter may cause problems when running. Physical properties such as properties and durability were sacrificed due to the use of dibutyl 7-talate as a plasticizer.

この点に鑑み、その物理特性の低下を改善するため、含
浸剤を塩酢ビ共重合体、ポリウレタン、ポリブタジェン
、ブタジエンーアタリロ二トリル共重合体などの樹脂と
したものは本山願人により特公昭５６−１５０４６とし
て示されている。このような樹脂を含浸剤とした硝化綿
は、走行時の摩擦変動・スチル再生時間などの物理特性
に優れた結果を示した。In view of this, in order to improve the deterioration of physical properties, Ganto Motoyama has developed a method using resins such as salt-vinyl acetate copolymer, polyurethane, polybutadiene, butadiene-atarylonitrile copolymer, etc. as an impregnating agent. It is shown as Kosho 56-15046. Nitrified cotton impregnated with such a resin showed excellent physical properties such as friction fluctuation during running and still playback time.

しかしながら該含浸剤の選択如何によって、それを結合
剤の一部とする磁気記録媒体の特性が大きく変動する事
が知見された。例えば、含浸剤として、塩化ビニルΦ酢
酸ビニル共重合体系の樹脂を用いた場合、かかる樹脂に
は、米国ＵＣＣ社のＶＡＧＨ（商品名）を代表例として
種々のものが提供されている。このうち、ＶＡＧＨは、
塩化ビニ／Ｉ／９１ｗｔ％、酢酸ビニル３ｗｔ％、ビニ
ルアルコール６ｗｔ％を構成物として有する共重合体で
あるこれは比較的に安価でかつ相溶性に優れ、ビニル７
７にコールのもつＯＨ基が磁性粉の分散性を高めるため
に、磁気記録媒体の結合材として広く使用されている。However, it has been found that, depending on the selection of the impregnating agent, the characteristics of the magnetic recording medium containing it as part of the binder vary greatly. For example, when a vinyl chloride Φ vinyl acetate copolymer resin is used as the impregnating agent, a variety of resins are available, with VAGH (trade name) manufactured by UCC Corporation in the United States being a representative example. Among these, VAGH is
It is a copolymer containing vinyl chloride/I/91wt%, vinyl acetate 3wt%, and vinyl alcohol 6wt% as constituents.
Since the OH group of Cole 7 improves the dispersibility of magnetic powder, it is widely used as a binder for magnetic recording media.

これに関し、発明者は特開昭５１−１２９２０２に示し
たように、ビニルアルコールのＯＨ基が、磁性粉との高
い親和性を保証している事を知見した。Regarding this, the inventor found that the OH group of vinyl alcohol guarantees high affinity with magnetic powder, as shown in JP-A-51-129202.

さらなる探求によってこれには単にＯＨ基の量ではなく
、ＯＨ基の数とＯＨ基の数の比が・重要な役割を演じて
いる事を知った。しかしながらＯＨ／ＣＨの高められた
塩化ビニル・酢酸ビニル系共重合体樹脂は樹脂金体のガ
ラス転移点を上昇させ、表面加工性を低下させるために
、磁気記録媒体の表面平滑性を高められず、電磁変換特
性を期待した梅肉上出来なかった。Through further investigation, I learned that it is not just the amount of OH groups, but the ratio of the number of OH groups to the number of OH groups that plays an important role. However, vinyl chloride/vinyl acetate copolymer resins with increased OH/CH raise the glass transition point of the resin metal body and reduce surface workability, making it impossible to improve the surface smoothness of magnetic recording media. However, the expected electromagnetic conversion properties of plum meat were not achieved.

本発明者は特願昭５６−９４０１４で、上記の大きいＯ
Ｈ／ＣＩ（比を有する塩化ビニル９酢酸ビニル共重合塩
化ビニルと共重合可能な！レイン酸、７Ｙ−ル酸、メタ
クリル酸、アクリル酸及びこれらのエステルなどの単量
体部分を有する６元共重合体を混用することを示し、ガ
ラス転移点を低下させると共に磁性粉の分散性を高めた
。The present inventor filed a Japanese patent application No. 56-94014 with the above-mentioned large O.
H/CI (vinyl chloride 9-vinyl acetate copolymerization with a ratio of 6-element copolymerizable with vinyl chloride and having monomer moieties such as leic acid, 7Y-ruic acid, methacrylic acid, acrylic acid, and their esters) The mixed use of polymers was shown to lower the glass transition point and improve the dispersibility of magnetic powder.

さらに特願ｆｆｆ！１５６−１ａ２２ｓ４等で、上記高
められたｏｎ／ａｎ比を有する樹脂中のｏｎ／ｃｍを低
減させ、且つその構成成分として単量体を導入した４元
共重合体を示し、物理特性を向上させた。Furthermore, special request fff! 156-1a22s4 etc., which shows a quaternary copolymer that reduces the on/cm in the resin with the above-mentioned increased on/an ratio and introduces a monomer as a constituent component, and improves the physical properties. Ta.

上記のような塩化ビニル酢酸ビニル系共重合体の特徴は
、それを含浸剤とする硝化綿にひきつがれ、それらを基
本系とする固着剤をもつ磁気記録媒体に反訣する。例え
ば前述のＶＡＧＨ等塩化ビニルと共重合可能な単量体を
含まない塩化ビニル、酢酸ビニル共重合体を含浸剤とす
るものは、硝化綿と相溶しないので、分散性に欠点を有
している。The characteristics of the vinyl chloride/vinyl acetate copolymer described above are inherited from the nitrified cotton that uses it as an impregnating agent, and are opposed to magnetic recording media that have a fixing agent based on these copolymers. For example, the above-mentioned VAGH and other impregnating agents that use vinyl chloride and vinyl acetate copolymers that do not contain monomers that can be copolymerized with vinyl chloride are not compatible with nitrified cotton, so they have disadvantages in dispersibility. There is.

また、同様にアル午ルカルポン酸ビニルエステルのナン
化切を適量に含まない塩化ビニル・酢酸ビニル系共重合
体を含浸剤とした硝化綿は、熱安定性に劣り塗膜乾燥中
の熱作用により赤変などを起す。Similarly, nitrified cotton impregnated with a vinyl chloride/vinyl acetate copolymer that does not contain a suitable amount of vinyl carboxyl ester has poor thermal stability and is susceptible to thermal effects during drying of the paint film. Causes red discoloration.

さらにＯＨ／ＣＨ＠収比をガラス転移点を高めすぎず、
高分散性を与える範囲即ち１１．２〜α７に選定すれば
、さらによい効果をもたらす。In addition, the OH/CH@ yield ratio does not raise the glass transition point too much,
Even better effects can be obtained by selecting a range that provides high dispersibility, that is, 11.2 to α7.

前記の４元塩化ビニル酢酸ビール系共重合体は、これを
含浸剤として用いれば、危−険防止の効果はもとより、
硝化綿との相溶性に優れ、熱安定性骨分散性が良好な磁
気記録媒体を与える。If the above-mentioned quaternary vinyl chloride/beer acetate copolymer is used as an impregnating agent, it will not only have the effect of preventing danger, but also
Provides a magnetic recording medium that has excellent compatibility with nitrified cotton and has good thermal stability and bone dispersibility.

本発明はこの４元共重合体、すなねち、塩化ビニルと、
アル午ルカルポン酸ビニルエステルと、塩化ビニル共重
合可能な単量体と、アル午ルカルボン酸ビニルエステル
のケン化物との共重合体、を硝化綿の含浸剤とする事を
提案し、硝化綿の安全性を増進すると共に、硝化綿と塩
化ビニル酢酸ビニル系共重合体のもつ高い分散性を保っ
たまま、塩化ビニルと共重合可能な単量体を含まない塩
化ビニルΦ酢酸ビニル系共重合体を含浸剤とする硝化綿
のもつ物理特性の欠陥を技善しまた、硬化剤の使用によ
って塗膜の強度を改善した、高い電磁変換特性と物理特
性をもつ磁気記録媒体を提供するものである。The present invention utilizes this quaternary copolymer, polyvinyl chloride, and
We proposed that a copolymer of vinyl carboxylate ester, vinyl chloride copolymerizable monomer, and saponified vinyl chloride carboxylate be used as an impregnating agent for nitrified cotton. A vinyl chloride/vinyl acetate copolymer that improves safety and maintains the high dispersibility of nitrified cotton and vinyl chloride/vinyl acetate copolymer, but does not contain monomers that can be copolymerized with vinyl chloride. The present invention provides a magnetic recording medium with high electromagnetic conversion characteristics and physical properties, which improves the physical property defects of nitrified cotton as an impregnating agent and improves the strength of the coating film by using a hardening agent. .

本発明の実施にあたって、硝化綿への４元共重合体の含
浸け、同じ出願人による特公昭５６−１５０４６にある
ように、例えばイソプｐピルアルコーＡ／會浸の硝化綿
と骸４元塩〜酢〜系共重金俸を混合しての熱置換で充分
実現され、その他よく知られた置換方法によっても効果
は同じである。In carrying out the present invention, nitrified cotton is impregnated with a quaternary copolymer, for example, as described in Japanese Patent Publication No. 56-15046 by the same applicant. This effect can be sufficiently achieved by heat substitution using a mixture of vinegar and copolymerized metal, and the same effect can be obtained by other well-known substitution methods.

又、硝化綿の外に、ポリウレタン樹脂、ポリアリリ一二
トリル、ポリエステル樹脂などが共用しうる〇 本発明はバインダー成分としてさらに硬化剤を用いるこ
とが必要である。特にポリイソシアネート系の硬化剤が
本発明の目的に適している。In addition to nitrified cotton, polyurethane resins, polyarylnitrile, polyester resins, etc. can also be used. In the present invention, it is necessary to further use a curing agent as a binder component. Particularly polyisocyanate-based curing agents are suitable for the purpose of the present invention.

以下に本発明の実施例と比較例を述べる。Examples and comparative examples of the present invention will be described below.

ｌ）４元塩化ビニル酢酸ビニル系共重合体の硝化綿の含
浸 硝化綿（ダイセル社製Ｈ捧）　　　　　　１０１０１Ｅ
イソプロピルアルコール３０％含浸）４元塩化ビニル酢
酸ビニル系共重合体（注１）（ＯＨ／ＣＨ吸収比：０、
Ｑ、２、（１３、α５、゛　　α７、Ｑ、９） 〔単量体（マレイン酸）量　０、α５、ｔｏ、ｔ５．２
．０．２．５．５．０（イ）〕０．５〜１２ｋｇ メチルエチルケトン　　　　全ｍ側ｘの１５％注１＝括
弧内の吸収比で示される量のケン化物と、括弧内の量で
示される単量体とを含む４元塩化ビニル・酢酸ビニル共
重合体。l) Nitrified cotton impregnated with nitrified cotton of quaternary vinyl chloride vinyl acetate copolymer (manufactured by Daicel Corporation) 10101E
30% isopropyl alcohol impregnated) Quaternary vinyl chloride vinyl acetate copolymer (Note 1) (OH/CH absorption ratio: 0,
Q, 2, (13, α5, ゛ α7, Q, 9) [Monomer (maleic acid) amount 0, α5, to, t5.2
．． 0.2.5.5.0 (a)] 0.5 to 12 kg Methyl ethyl ketone 15% of the total m side A quaternary vinyl chloride/vinyl acetate copolymer containing a monomer.

以上の材料をニーダ−により混練し、硝化綿と４元塩化
ビニ／Ｉ／＠酢酸ビニル共重合体を混合した後熱ｐ−ル
（３０〜４０℃）を用いて溶剤を蒸散しシート状の樹脂
とし、室温で残留溶剤を揮発させた。The above materials were kneaded in a kneader, and the nitrified cotton and the quaternary vinyl chloride/I/@vinyl acetate copolymer were mixed, and then the solvent was evaporated using a heated poll (30 to 40°C) to form a sheet. The resin was prepared and the residual solvent was evaporated at room temperature.

その後チップ状に粉砕加工した。It was then crushed into chips.

この塩化ビニル・酢酸ビニル共重合体を含浸した硝化綿
を以下本発明塩酢ビ含浸硝化綿と呼ぶ。The nitrified cotton impregnated with this vinyl chloride/vinyl acetate copolymer is hereinafter referred to as the nitrified cotton impregnated with vinyl acetate according to the present invention.

また４元塩化ビニル嗜酢酸ビニル共重合体を従来の塩化
ビニル・酢酸ビニル共重金体（ＯＨを含み単量体の入ら
ないもの）に変更して同様に１４成したものを従来品塩
酢ビ含浸硝化綿と呼ぶ。In addition, the conventional vinyl chloride/vinyl acetate copolymer was changed from the quaternary vinyl chloride/vinyl acetate copolymer to the conventional vinyl chloride/vinyl acetate copolymer (containing OH and containing no monomer) to form 14. It is called impregnated nitrified cotton.

以下の実施例・比較例には発明の本質的部分である結合
材および磁性粉のみを示したが必要に応じて磁気記録媒
体に添加される以下のような添加剤を用いても得られる
効果は同じである。なお添えられた数字は磁性粉１００
重量部に対して実施例・比較例に共通して添加した重置
部である。In the Examples and Comparative Examples below, only the binder and magnetic powder, which are the essential parts of the invention, are shown, but the effects can also be obtained by using the following additives added to the magnetic recording medium as necessary. are the same. The attached number is magnetic powder 100
This is the overlapping part added in common to the Examples and Comparative Examples based on the weight part.

ｍ肪酸−そのエステル−シリコンオイル痔　２カーボン
プラツタ　　　　　　　　　　　　　Ｓ研摩剤　　　　
　　　　　　　　　　　　　２１１）本発明塩酢ビ含浸
硝化綿の磁気記録媒体への適用 実施例１ 本発明塩酢ビ含浸硝化綿（注１）１６〜４０ｆ（ＯＨ７
ＣＨｇ＆収比：　０、（１２，０，５，０，５，０，７
、（Ｌ９） 〔単量体（マレイン酸）量　０．０．５、ｔｏ、ｔ５．
２．０．２．５、五〇（イ）〕 硝化綿／塩酢ビ系共重合体（重量比） ０．６〜９ ポリウレタン樹脂（成田薬品工業社製 １Ｅ５５０）　　　　　　　　　　４〜１４ｆ磁性粉　
　　　　　　　　　１２０〜２００ｆ硬化剤（日本ポリ
ウレタン社製コルネートＬ）１２〜５６ｆ 注１；括弧内は１）に記載した４元塩化ビニル・酢酸ビ
ニル共重合体における量比である。m fatty acids - their esters - silicone oil hemorrhoids 2 carbon platters S abrasives
211) Example 1 of application of the salt-vinyl acetate-impregnated nitrified cotton of the present invention to magnetic recording media 16-40f (OH7
CHg & yield ratio: 0, (12,0,5,0,5,0,7
, (L9) [Monomer (maleic acid) amount 0.0.5, to, t5.
2.0.2.5, 50 (a)] Nitrified cotton/salt-vinyl acetate copolymer (weight ratio) 0.6-9 Polyurethane resin (1E550 manufactured by Narita Pharmaceutical Co., Ltd.) 4-14f magnetic powder
120-200f curing agent (Cornate L manufactured by Nippon Polyurethane Co., Ltd.) 12-56f Note 1: The amount in parentheses is the quantitative ratio in the quaternary vinyl chloride/vinyl acetate copolymer described in 1).

実施例２ 実施例１と同じ本発明塩酢ビ含浸硝化綿１６〜４０ｆ ポリウレタン樹脂（日本ポリウレタン社製ニラボラン＋
５ｏｉｉ）　　　　　ｓ〜１４ｆポリエステル樹脂（バ
イエル社製デスモヘンを２２００）　　　　　　　　　
　ｉ〜１４ｆ磁性粉　　　　　　　　　　１２０〜２０
０ｆ硬化剤（！１本ポリウレタン社製コロ本−トＬ）１
２〜５４ｆ ｔ；Ｄ　　従来のＩＦム（イソプルピルアルコール）含
浸硝化綿の例 比較例 硝化綿（ダイセル社製ＨＶ２）　　　　９〜４４ｆ（イ
ソプロピルアルコール含浸） ４元塩化ビニル・酢酸ビニル共重合体（注１）５〜５０
　ｒ！ （ＯＨ／ＣＨ［数比；口、（Ｌ２、α５．０．５、（Ｌ
７、α９） 〔単量体（マレイン酸）量：口、［Ｌｉ、１０゜ｔ５．
２．ｐ、２−５、五〇に）〕 硝化綿／塩酢ビ系共重合体（重量比） ａ６〜９ ポリウレタン樹脂（試用薬品１Ｅ５５０）４〜１４２ 磁性粉　　　　　　　　　　１２０〜２００ｆ硬化剤（
日本ポリウレタン社製コロネートし）１２〜６６１ 注１＝前記１）で用いたと同じ４元塩化ビニル・酢酸ビ
ニル共重合体。本比較例ではこの共重合体は硝化綿に含
浸されない。Example 2 Same as Example 1 Salt-vinyl acetate impregnated nitrified cotton 16-40f Polyurethane resin (Niboran + manufactured by Nippon Polyurethane Co., Ltd.)
5oii) s~14f polyester resin (Desmohen 2200 manufactured by Bayer)
i~14f magnetic powder 120~20
0f hardening agent (! 1 piece Coromoto L manufactured by Polyurethane Co., Ltd.) 1
2~54f t;D Example of conventional IF membrane (isopropyl alcohol) impregnated nitrified cotton Comparative example Nitrified cotton (HV2 manufactured by Daicel) 9~44f (isopropyl alcohol impregnated) Quaternary vinyl chloride/vinyl acetate copolymer ( Note 1) 5-50
r! (OH/CH [number ratio; mouth, (L2, α5.0.5, (L
7, α9) [Monomer (maleic acid) amount: mouth, [Li, 10°t5.
2. p, 2-5, 50)] Nitrified cotton/salt-vinyl acetate copolymer (weight ratio) a6-9 Polyurethane resin (trial chemical 1E550) 4-142 Magnetic powder 120-200f hardening agent (
Coronate (manufactured by Nippon Polyurethane Co., Ltd.) 12-661 Note 1 = the same quaternary vinyl chloride/vinyl acetate copolymer used in 1) above. In this comparative example, this copolymer was not impregnated into the nitrified cotton.

ｉ■）従来品塩酢ビ含浸硝化綿の例（塩化ビニルと共重
合可能な単量体を含まないもの） 比較例２ 従来品塩酢ビ含浸硝化綿 （ＯＨ／ＣＨ［数比：　０．０．２、ａ、ｓ、［Ｌ５．
１７．０．９）　　　　　　　　　１６〜４０ｆ硝化締
／塩酢ビ系共重合体　　　　　０．６〜？ポリウレタン
樹脂（＃Ｅ５５０）　６〜１４ｆ磁性粉　　　　　　　
　　　１２０〜２００ｖ硬化剤（コロネートＬ）　　　
　　１堡〜Ｓ６ｆ以上のような組成惣に、前述の添加剤
を加え、常法により溶剤を加えて混合分散を行って磁性
塗料とし、ポリエチレンテレフタレートフィルム上に塗
布し、乾燥し、表面平滑加工を施し、所定の幅に切断し
て磁気テープとした。i■) Example of conventional salt-vinyl acetate-impregnated nitrified cotton (contains no monomer copolymerizable with vinyl chloride) Comparative example 2 Conventional salt-vinyl acetate-impregnated nitrified cotton (OH/CH [numerical ratio: 0. 0.2, a, s, [L5.
17.0.9) 16~40f Nitrification/salt vinyl acetate copolymer 0.6~? Polyurethane resin (#E550) 6~14f magnetic powder
120-200v curing agent (Coronate L)
Add the above-mentioned additives to the composition of 1 to S6f or more, mix and disperse by adding a solvent in a conventional manner to obtain a magnetic paint, apply it on a polyethylene terephthalate film, dry it, and smooth the surface. It was then cut into a predetermined width to make a magnetic tape.

以下に結果の一部を示す。Some of the results are shown below.

硝化綿／塩酢ビ系共重合体を３／１（重置比）とした時
に実施例１と比較例２の表面加工前後の光沢度によって
分散性の差を第１図に示す。FIG. 1 shows the difference in dispersibility between Example 1 and Comparative Example 2 depending on the gloss level before and after surface treatment when the nitrified cotton/salt-vinyl acetate copolymer was set to 3/1 (superposition ratio).

分散性の評価には、村上色彩社製表面光沢度計ＧＭ３Ｄ
を用い、白色光を塗膜表面に対して４０’の入射角で入
射させ、６［Ｐの反射光強度を標準反射板（６０°入射
時に９／１％の反射率を有する）に対する同じ測定の結
果を％で示した。For evaluation of dispersibility, a surface gloss meter GM3D manufactured by Murakami Color Co., Ltd.
, the white light was incident on the coating surface at an incident angle of 40', and the reflected light intensity of 6[P was measured in the same manner against a standard reflector (having a reflectance of 9/1% at 60° incidence) The results are shown in %.

図から明らかなように、表面平滑加工前ではＯＨ／ＣＨ
の増大に伴い表面光沢度が増大するが、加工後ではＯＨ
基の絶対量の増加と共にガラス転移点が上昇するので表
面加工の効果が少なくなっている。マレイン酸が含浸用
樹脂の構成成分として含まれるとマレイン酸が禽まれな
（′％含浸用樹脂を用いる場合に比して面光獣炭が改善
されることが分る。As is clear from the figure, before surface smoothing, OH/CH
The surface gloss increases with the increase in OH, but after processing the OH
As the absolute amount of groups increases, the glass transition temperature increases, so the effect of surface treatment decreases. It can be seen that when maleic acid is included as a component of the impregnating resin, the charcoal quality is improved compared to when the impregnating resin is used.

第２図はに′巾に切断したテープをＶＨ８デツキ（松下
ＮＶ−８１００）で４０％Ｃ，８０’５００回繰返し走
行試験を実施した際のヘッド目詰りによる４ＭＨｚの信
号で再生出力のｉｄＢ以上の低下の発生率を５０巻の供
試テープで実施した時′の実施例１と比較例１で硝化綿
／塩酢ビ４／ｉ（重量比）、単量体１％とした時を示す
。図から分るように、マレイン酸を含浸用樹脂の構成部
分として含むと、出力低下の発生が遅れることが分る。Figure 2 shows a 4MHz signal that exceeds the playback output idB due to head clogging when a tape cut into widths was run 500 times at 40%C on a VH8 deck (Matsushita NV-8100). This shows the incidence of decrease in nitrified cotton/salt vinyl acetate 4/i (weight ratio) and 1% monomer in Example 1 and Comparative Example 1 when conducted with 50 rolls of sample tape. . As can be seen from the figure, when maleic acid is included as a constituent part of the impregnating resin, the occurrence of a decrease in output is delayed.

これに対してイソプ■ビルアルコールを含浸した硝化綿
を用いると、本発明で含浸用として用いた４元塩化ビニ
ル・酢酸ビニル共重合体がバインダー成分として混用さ
れたとしても十分な改善を示すことはできなかった。　
゛ また、実施例２に示すようにポリウレタン樹脂に代えて
ポリエステル樹脂を用いたとき、実施例１の場合と同様
にすぐれた効果が確認された。On the other hand, the use of nitrified cotton impregnated with isopropyl alcohol shows sufficient improvement even when the quaternary vinyl chloride/vinyl acetate copolymer used for impregnation in the present invention is mixed as a binder component. I couldn't.
Furthermore, as shown in Example 2, when polyester resin was used instead of polyurethane resin, excellent effects were confirmed as in Example 1.

さらに、硬化剤をバインダー成分の一部として含有させ
ると実施例１において硬化剤を含めないで製造した塗膜
に比してヘッド目詰りによる信号低下がさらに減じるこ
とが分った。Furthermore, it was found that when the curing agent was included as part of the binder component, the signal drop due to head clogging was further reduced compared to the coating film produced without the curing agent in Example 1.

第１図は本発明及び比較例の磁気記録媒体における表面
光沢度とＯＨ／ＣＨ比及びマレイン酸含有率との間係を
示すグラフ、及び第２図はＯＨ／ＣＨ比及びマレイン酸
含有率が出力低下に及ぼす影智を示すグラブである。FIG. 1 is a graph showing the relationship between surface glossiness, OH/CH ratio, and maleic acid content in magnetic recording media of the present invention and comparative examples, and FIG. 2 is a graph showing the relationship between OH/CH ratio and maleic acid content. This is a graph that shows the influence it has on output reduction.

第１図 ＯＨ／ＣＨ咳収比 １数比− ＯＨ／ＣＨ９友　！又地 手続補正書 昭和５７年　９月１０日 特許庁長官　若　杉　和　夫　殿 事件の表示　昭和５７年特　願第　１５４６９０号発明
の名称　磁気記録媒体 補正をする者 事件との関係　　　　　　　　　　特許出願人名　称　
（！１０６）東京電気化学工業株式会社代理人 〒１０３ ｍ−−胆倉 補正の対象 １目 明細書の峠寺許請求の範囲・発明の詳細な説明の欄補正
の内容　　別紙の通り 明細書を次の通り補正する。Figure 1 OH/CH cough relief ratio 1 number ratio - OH/CH9 friends! Written amendment to the land procedure September 10, 1980 Kazuo Wakasugi, Commissioner of the Patent Office Indication of the case Patent Application No. 154690 of 1988 Name of the invention Relationship to the case of the person who amends the magnetic recording medium Name of the patent applicant Title
(!106) Tokyo Denki Kagaku Kogyo Co., Ltd. Agent 〒103 m--Togedera of the first specification subject to the Ikura amendment Contents of the amendment in the scope of claims/detailed explanation of the invention The description as shown in the attached sheet Correct as follows.

１　特許請求の範囲の項を次の通り訂正する。1. The scope of claims is amended as follows.

［２、特許請求の範囲 ｔ　（イ）塩化ビニル、アルキルカルボン酸ビニルエス
テル、塩化ビニルと共重合可能な単量体、及びアルキル
カルボン酸ビニルエステルのケン化物を構成部分とする
共重合体を含浸剤として含む硝化綿と、（ロ）ゴム系バ
インダと、（ハ）硬化剤とを樹脂成分として含む結合材
によって支持体上に磁性粉末を固着してなる磁気記録媒
体。[2. Claims t (a) Impregnated with a copolymer containing vinyl chloride, an alkyl carboxylic acid vinyl ester, a monomer copolymerizable with vinyl chloride, and a saponified product of the alkyl carboxylic acid vinyl ester as a constituent part A magnetic recording medium in which magnetic powder is fixed onto a support using a binder containing nitrified cotton as an agent, (b) a rubber-based binder, and (c) a curing agent as resin components.

２　含浸剤が、塩化ビニル５０〜９０重量％、アルキル
カルボン酸ビニルエステＡ１５〜４０重量％、 塩化ビニルと共重合可能な単量体　１０〜５．０重量％
、及び 残余が実質的にアルキルカルボン酸ビニルエステルのケ
ン化物であり、その赤外吸収の０）ｉ１０Ｈ比が［Ｌ２
〜ＩＩＬ７である特許請求の範囲１に記載の磁気記録媒
体。2. The impregnating agent is 50 to 90% by weight of vinyl chloride, 15 to 40% by weight of alkyl carboxylic acid vinyl ester A, and 10 to 5.0% by weight of a monomer copolymerizable with vinyl chloride.
, and the remainder is substantially a saponified product of alkyl carboxylic acid vinyl ester, and the 0)i10H ratio of its infrared absorption is [L2
The magnetic recording medium according to claim 1, which is IIL7.

五　ゴム系バインダが、ポリエステル樹脂、ウレタン樹
脂またはこれらの組合せである特許請求の範囲１又は２
に記載の磁気記録媒体。(v) Claim 1 or 2, wherein the rubber binder is a polyester resin, a urethane resin, or a combination thereof.
The magnetic recording medium described in .

４、含浸剤と硝化綿の重量比が、１０：９０〜６０：４
０である特許請求の範囲１又は２に記載の磁気記録媒体
。4. The weight ratio of impregnating agent and nitrified cotton is 10:90 to 60:4
3. The magnetic recording medium according to claim 1 or 2, wherein the magnetic recording medium is 0.

５、　硬化剤を除く全樹脂の重量を１００とした時に、
前記含浸刻入りの硝化綿が４０〜８５、ゴム系バインダ
が１５〜６０であり、かつ硬化剤が１０〜３０である特
許請求の範囲１又は２に記載の磁気記録媒体。」 ２、　第５頁第１０行に「共重合」（初出）とある次に
「体、」と加入する。5. When the weight of all resin excluding curing agent is 100,
3. The magnetic recording medium according to claim 1, wherein the impregnated and carved nitrified cotton has a molecular weight of 40 to 85, the rubber binder has a molecular weight of 15 to 60, and the curing agent has a molecular weight of 10 to 30. 2. On page 5, line 10, after the word ``copolymerization'' (first appearance), ``body'' is added.

五　第７頁第１行に１塩化ビニル」とある次に１と」と
加入する。5. In the first line of page 7, next to "vinyl chloride", add "1".

４、　第７頁第１１行の次に、以下の文を加入する。4. Add the following sentence after page 7, line 11.

［上記の４元共重合体の構成成分中、アルキルカルボン
酸ビニルエステルは酢酸ビニルが好ましく、また塩化ビ
ニルと共重合可能な単量体はマレイン酸、７マール酸、
メタクリル酸、アクリル酸及びこれらのエステルであり
、特にマレイン酸が好ましい。」 ５．　同頁第１５行に「塩〜酢〜糸」とあるを「塩化ビ
ニル・酢酸ビニル系」と訂正する。[Among the constituent components of the above quaternary copolymer, the alkyl carboxylic acid vinyl ester is preferably vinyl acetate, and the monomers copolymerizable with vinyl chloride are maleic acid, hexamaric acid,
Methacrylic acid, acrylic acid and esters thereof, with maleic acid being particularly preferred. ” 5. In line 15 of the same page, the phrase ``salt, vinegar, and thread'' is corrected to ``vinyl chloride/vinyl acetate type.''

４　第１０頁第８行に「（重量比）」とある次に「（注
２）」と加入する。4. On page 10, line 8, after "(weight ratio)", add "(Note 2)".

ｌ　同頁下から第４行の次に、次の文を加入する。l Add the following sentence after the fourth line from the bottom of the same page.

［注２：本発明塩酢ビ含浸硝化綿の含浸比を示す。」ａ
　第１１頁下から第２行に「（重量比）」とある次に次
の文を加入する。[Note 2: Shows the impregnation ratio of the salt-vinyl acetate-impregnated nitrified cotton of the present invention. ”a
In the second line from the bottom of page 11, next to "(weight ratio)", add the following sentence.

「注２；注１に示した共重合体と硝化綿の比」貴　第１
４頁第６行に「塩酢ビ」とある次に「共重合体」ど無人
する。"Note 2; Ratio of copolymer and nitrified cotton shown in Note 1" No. 1
On page 4, line 6, there is ``salt vinyl acetate'', followed by ``copolymer''.

１０３−103-

Claims (1)

【特許請求の範囲】 ｔ　（イ）塩化ビニル寥アルキルカルボン酸ビニルエス
テル、塩化ビニルと共重合可能な単量体、及びアルキル
カルボン酸ビニルエステルのケン化物を構成部分とする
共重合体を含浸剤として含む硝化綿と、（ロ）ゴム系バ
インダと、（ハ）硬化剤とを樹脂成分として含む結合材
によって支持体上に磁性粉末ｆ：固着してなる磁気記録
媒体。 ２　含浸剤が、塩化ビニル５０〜９０重量優、アルキル
カルボン酸ビニルエステル　５〜４０重量メ重 量化ビニルと共重合可能な単量体　ｔｏ−５，０重量％
、及び 残余が実質的にアルキルカルボン酸ビニルエステルのケ
ン化物であり、その赤外吸収のＯＨ／ＣＨ比が０．２〜
［１７である特許請求の範囲１に記載の磁気記録媒体Ｏ Ｉ　　ゴム系バインダが、ポリエステルｔｌｄｊＬｖ＞
レタン樹脂またはこれらの組合せである特許請求の範囲
１又は２に記載の磁気記録媒体。 ４、　含浸剤と硝化綿の重量比が、１０：９０〜４０：
４０である特許請求の範囲１又は２に記載の磁気記録媒
体◇ 五　全樹脂の重量を１００とした時に、前記含浸刻入り
の硝化綿が４０〜８５、ゴム系バインダが１５〜６０で
あり、かつ硬化剤が１０〜６０である特許請求の範囲１
又は２に記載の磁気記録媒体。[Claims] t (a) An impregnating agent containing a copolymer containing vinyl chloride-alkyl carboxylic acid vinyl ester, a monomer copolymerizable with vinyl chloride, and a saponified product of alkyl carboxylic acid vinyl ester as a constituent part. A magnetic recording medium in which magnetic powder (f) is fixed on a support by a binder containing as resin components: nitrified cotton, (b) a rubber-based binder, and (c) a curing agent. 2 The impregnating agent is a monomer copolymerizable with vinyl chloride 50 to 90% by weight, alkyl carboxylic acid vinyl ester 5 to 40% by weight vinyl, to-5.0% by weight.
, and the remainder is substantially a saponified product of alkyl carboxylic acid vinyl ester, and the OH/CH ratio of infrared absorption is 0.2 to
[17] The magnetic recording medium O I rubber-based binder according to claim 1 is polyester tldjLv>
The magnetic recording medium according to claim 1 or 2, which is a urethane resin or a combination thereof. 4. The weight ratio of impregnating agent and nitrified cotton is 10:90 to 40:
The magnetic recording medium according to claim 1 or 2, wherein the weight of the impregnated and carved nitrified cotton is 40 to 85, and the rubber binder is 15 to 60, when the weight of the total resin is 100. and the curing agent is 10 to 60.
Or the magnetic recording medium according to 2.