JP4024317B2 - Fluorine-containing carboxylic acid amine salt and magnetic recording medium provided with the same - Google Patents

Description

【０００５】
【化３】

【０００６】
【化４】

【０００７】
【発明が解決しようとする課題】
しかし、上記式（化２）、（化３）及び（化４）等で示される潤滑剤は磁気テープを高温高湿度の環境下で保存すると潤滑剤がバックコート面に転写して、磁性層表面の潤滑剤量が減少し潤滑性が低下するという問題があった。この潤滑性の低下は保存後の繰り返し走行の耐久性よりもスチル耐久性の劣化として顕著に現われる。
【０００８】
本発明は上記の従来の問題を解決するもので、高温高湿度の環境下での保存後においても潤滑性の低下しない物質及びそれを表面に付与した磁気記録媒体を提供することを目的とする。
【０００９】
【課題を解決するための手段】
上記の目的を達成するための本発明の含フッ素カルボン酸アミン塩は、前記一般式（化１）で示されるものである。
【００１０】
前記式（化１）においては、Ｒ¹は炭素数が１０〜２４の脂肪族アルキル基または脂肪族アルケニル基を示し、Ｒ² は炭素数が６〜１８のフロロアルキル基、炭素数が６〜１８のフロロアルケニル基、炭素数が６〜１２のフロロフェニル基、または炭素数が５〜３０のフロロアルキルエーテル基を示し、Ｒ³及びＲ⁴は炭素数が１〜１０の飽和または不飽和の炭化水素鎖を示し、Ｒ⁵ は炭素数が６〜１８のフロロアルキル基、または炭素数が６〜１８のフロロアルケニル基を示し、Ｒ⁶及びＲ⁸は炭素数が１〜１０の飽和または不飽和の炭化水素鎖を示し、Ｒ⁷及びＲ⁹ は炭素数が６〜１８のフロロアルキル基、または炭素数が６〜１８のフロロアルケニル基であることが好ましい。
【００１１】
次に本発明の磁気記録媒体は、基材フィルムの上に強磁性膜を設け、その強磁性膜の上に直接または保護膜を介して前記一般式（化１）で示される含フッ素カルボン酸アミン塩を含有する潤滑剤層を設けたものである。
【００１２】
前記においては、潤滑剤層の潤滑剤の存在量が、表面１ｍ² 当り０．１〜５０mgの範囲であることが好ましい。
また前記においては、潤滑剤が、前記一般式（化１）で示される含フッ素カルボン酸アミン塩を９０重量％以上含むことが好ましい。
【００１３】
また前記においては、潤滑剤が、前記一般式（化１）で示される含フッ素カルボン酸アミン塩５０重量％以上と、他の含フッ素化合物の潤滑剤及び防錆剤を含む組成物であることが好ましい。たとえば、他の含フッ素化合物の潤滑剤としては、Ｃ₁₇Ｈ₃₃ＣＯＯＣ₂ Ｈ₄ Ｃ₆ Ｆ₁₃があり、他の含フッ素化合物の防錆剤としては、Ｃ₈ Ｆ₁₇Ｃ₂ Ｈ₄ ＮＨＣ₁₈Ｈ₃₅等がある。
【００１４】
また前記においては、他の含フッ素化合物の潤滑剤及び防錆剤が、液体系の含フッ素化合物であることが好ましい。
また前記においては、保護膜が、膜厚５〜５０ｎｍのアモルファス状カーボン薄膜、グラファイト状カーボン薄膜、ダイヤモンド状カーボン薄膜またはそれらの混合状態、及び積層状カーボン薄膜から選ばれる少なくとも一つの薄膜であることが好ましい。
【００１５】
また前記においては、基材フィルムが、膜厚３〜３０μｍの範囲のポリエチレンテレフタレート、ポリエチレン ２，６−ナフタレート、ポリイミドから選ばれる少なくとも一つのフィルムであることが好ましい。
【００１６】
また前記においては、強磁性膜が、Ｃｏ−Ｎｉ−Ｏ系合金酸化物膜であることが好ましい。厚さは８０〜３００ｎｍ（８００〜３０００オングストローム）の範囲が好ましい。
【００１７】
また前記においては、基材フィルムの裏面にバックコート層が形成されていることが好ましい。
また前記においては、バックコート層が、バインダー樹脂とフィラー物質とを含む組成物であることが好ましい。
【００１８】
また前記においては、バインダー樹脂がポリエステルエラストマ，ニトロセルロースから選ばれる少なくとも一つの樹脂であり、フィラー物質が炭酸カルシウム，カーボンブラックから選ばれる少なくとも一つの粒子であることが好ましい。
【００１９】
【作用】
本発明の含フッ素カルボン酸アミン塩は同一分子内に２個の含フッ素炭化水素末端基、すなわちフロロアルキル末端基、フロロアルケニル末端基、フロロフェニル末端基またはフロロアルキルエーテル末端基と１個の脂肪族炭化水素末端基、すなわち脂肪族アルキル末端基または脂肪族アルケニル末端基とアミノ・カルボキシル基を有する構造である。ここで、含フッ素炭化水素末端基は疎油性であるため、炭化水素系ポリマーから構成されるバックコート層との親和性に乏しい。一方、親油性の脂肪族炭化水素末端基はバックコート層との親和性に富んでいるが、含フッ素炭化水素末端基が同一分子内に脂肪族炭化水素末端基よりも多く存在すると分子全体としては疎油性が強くなり、バックコート層との親和性が弱くなる。このため、含フッ素カルボン酸アミン塩はバックコート層への転写すなわち磁性層表面からの減少が抑えられ、磁気テープは経時劣化を起こさない。
【００２０】
ところで、アミノ・カルボキシル基は金属薄膜の表面または保護膜の表面と磁気ヘッドの表面に強く付着する。また、含フッ素炭化水素末端基は表面に露出してその表面の低エネルギー化に寄与し、非粘着面を形成する。さらに、脂肪族炭化水素末端基は柔軟な炭素−炭素結合鎖であるために良好な潤滑性を示す。そして、これらの各末端基の相乗効果により低湿度環境（たとえば５℃、５％ＲＨ）から高湿度（たとえば４０℃、８０％ＲＨ）環境に至る全環境において優れた潤滑性を発現する。
【００２１】
【実施例】
（実施例１）
以下、本発明の第１の実施例について具体的に説明する。本実施例の物質は下記式（化５）で示されるものである。
【００２２】
【化５】

【００２３】
前記式（化５）の化合物は、分子量１，６０３である。上記の物質を前記式（化１）の一般式と比較しながら説明すると、Ｒ¹ が炭素数１８の脂肪族アルキル基で、Ｒ² がフッ素と結合した炭素を１１個有するフロロアルキルエーテル基で、Ｒ³ が炭素数１の炭化水素鎖で、Ｒ⁴ が炭素数１０の飽和の炭化水素鎖で、Ｒ⁵ がフッ素と結合した炭素を９個有し、結合基としてエーテルを有するフロロアルケニル基で、ｎが１のものである。
【００２４】
次に、前記式（化５）で示される物質の製造方法を説明する。出発原料はＴＧ式（化６）で示されるフロロアルケニル基付アミンと下記式（化７）で示される物質である。
【００２５】
【化６】

【００２６】
【化７】

【００２７】
前記式（化７）で示される物質はオクタデシル無水コハク酸と、１Ｈ, １Ｈ−パーフロロ−２, ５, ８−トリメチル−３, ６, ９−トリオキサウンデカン−１−オールから合成されたものである。すなわち、前記式（化７）で示される原料１００. ０ｇ（０. １０モル）と酢酸エチル１０００mlを撹拌翼を備えた２リットルのフラスコに採取し、１５℃に冷却した後、酢酸エチル４００mlに溶解した化学式６で示される原料６６. ４ｇ（０. １１モル）を滴下した。滴下終了後、反応溶液を室温に戻して２時間撹拌を続けた。反応終了後、反応溶液を０℃に冷却して反応生成物を再結晶させ、減圧ろ過により未反応のフロロアルケニル基付アミンを除去して、融点７２℃の白色固体１１５g を得た。この白色固体は赤外分光分析（ＩＲ）、ゲルパーミエーションクロマトグラフィ（ＧＰＣ）および有機質量分析（ＦＤ−ＭＳ）により、出発原料および副生成物を含まない化学式５で示される含フッ素カルボン酸アミン塩であることが確認できた。
【００２８】
ＩＲ；カルボン酸の１, ７０５cm^-1の吸収ピーク消滅、カルボン酸アミン塩の１５４０cm^-1の吸収ピーク出現（図３）。
ＧＰＣ；出発原料および副生成物検出されず。
【００２９】
ＦＤ−ＭＳ；ｍ／ｅ １, ６０３に主ピーク有り。
（実施例２）
つぎに、本発明の第２の実施例について具体的に説明する。本実施例の物質は下記式（化８）で示されるものである。
【００３０】
【化８】

【００３１】
前記式（化８）の化合物は、分子量１，３１６であった。前記式（化８）の物質を前記式（化１）の一般式と比較しながら説明すると、Ｒ¹ が炭素数１８の脂肪族アルケニル基で、Ｒ² がフッ素と結合した炭素を６個有するフロロアルキル基で、Ｒ³ が炭素数１１の不飽和の炭化水素鎖で、Ｒ⁴ が炭素数３の飽和の炭化水素鎖で、Ｒ⁵ がフッ素と結合した炭素を８個有するフロロアルキル基で、ｎが０のものである。
【００３２】
つぎに、前記式（化８）で示される物質の製造方法を説明する。出発原料は下記式（化９）で示されるフロロアルキル基付アミンと下記式（化１０）で示される物質である。この下記式（化１０）で示される物質は２−オクタデセニル無水コハク酸と１１−（パーフロロ−ｎ−ヘキシル）−１０−ウンデセノールから合成されたものである。
【００３３】
【化９】

【００３４】
【化１０】

【００３５】
前記式（化１０）で示される原料８３. ９ｇ（０. １０モル）と酢酸エチル１０００mlを撹拌翼を備えた２リットルのフラスコに採取し、１５℃に冷却した後、酢酸エチル４００mlに溶解した前記式（化９）で示される原料５２. ５ｇ（０. １１モル）を滴下した。滴下終了後、反応溶液を室温に戻して２時間撹拌を続けた。反応終了後、反応溶液を−２０℃に冷却して反応生成物を固化析出させ、低温ろ過により未反応のフロロアルキル基付アミンを除去して、無色透明の液体８８g を得た。この無色透明の液体はＩＲ、ＧＰＣおよびＦＤ−ＭＳにより、出発原料および副生成物を含まない化学式８で示される含フッ素カルボン酸アミン塩であることが確認できた。
【００３６】
ＩＲ；カルボン酸の１, ７０５cm^-1の吸収ピーク消滅、カルボン酸アミン塩の１５４０cm^-1の吸収ピーク出現（図４）。
ＧＰＣ；出発原料および副生成物検出されず。
【００３７】
ＦＤ−ＭＳ；ｍ／ｅ １, ３１６に主ピーク有り。
（実施例３）
つぎに、本発明の磁気記録媒体について説明する。まず図１は、本発明の一実施例の磁気記録媒体の断面図である。図１において、１は膜厚３〜３０μｍの範囲のポリエチレンテレフタレート、ポリエチレン ２，６−ナフタレート、ポリイミドから選ばれる少なくとも一つの基材フィルムである。２はＣｏ−Ｎｉ−Ｏ系合金酸化物メッキ膜などの強磁性膜、３は本発明の含フッ素カルボン酸アミン塩で形成されている潤滑剤層、４はバックコート層である。バックコート層４は、たとえばポリエステルエラストマ（ポリブチレンテレフタレート−ポリテトラフロロエーテル共重合体）（東洋紡社製”バイロン”）３０重量％、ニトロセルロース２０重量％、炭酸カルシウム微粒子３０重量％及びカーボンブラック２０重量％で構成され、厚さ３〜１０μｍの範囲、表面抵抗１０¹⁰オーム／ｃｍ² 以下であることが好ましい。
【００３８】
次に図２は、強磁性膜２と潤滑剤層３の間に保護膜５を設けた例である。保護膜５を設けることにより、強磁性膜２の酸化劣化を防止でき長期間安定して使用できる。なお、図１〜２において、基材フィルム１と強磁性膜２の接着性を上げるため、基材フィルム１の表面に中間層を設けても良い。
【００３９】
以下具体的実施例を説明する。
本実施例の磁気記録媒体の基材フィルム１は、ポリエチレンテレフタレートフィルム内に添加されたシリカ微粒子による勾配のゆるやかな粒状突起（平均高さ７ｎｍ（７０オングストローム）、直径１μｍ）が表面１００μｍ² 当り数個存在し、しかも重合触媒残さに起因する微粒子による比較的大きな突起を極力低減させたポリエステルフィルムを用いた。その表面に、平均直径１５ｎｍ（１５０オングストローム）のシリカコロイド粒子を核とし、紫外線硬化エポキシ樹脂を結合剤とする急峻な山状突起を１mm² 当り１×１０⁷ 個となるように中間層を形成させた。中間層の厚さは約１５μｍであった。そして、その非磁性支持体の上に連続真空斜め蒸着法によりＣｏ−Ｎｉの強磁性膜２（Ｎｉ含有量２０atm ％、膜厚１００ｎｍ（１０００オングストローム））を微量の酸素の存在下で設けた。強磁性膜中の酸素含有量は原子分率で５％であった。
【００４０】
つぎに、上記の強磁性膜の上に前記式（化５）で示される含フッ素カルボン酸アミン塩を１ｍ² 当り１０mgの存在量になるように塗布して潤滑剤層３を形成させた後、所定幅に裁断して磁気テープＡを作製した。また、強磁性膜の上にプラズマＣＶＤ法によって厚さ５ｎｍ（５０オングストローム）のダイヤモンドライクカーボンの保護膜を形成させた後、磁気テープＡと同様にして磁気テープＢを作製した。その磁気テープを４０℃、９０％ＲＨの環境下で１週間保存した後、Ｘ線光電子分光分析法（ＥＳＣＡ）で磁性層表面の保存前後のフッ素残存率を調べた。また、２３℃、１０％ＲＨと４０℃、８０％ＲＨの環境下で市販のビデオデッキに掛けてスチル再生時の出力特性を測定し、ＲＦ出力が初期値に対し３ｄＢ低下するかまたは出力変動の発生し始めるまでのスチル耐久時間を求めた。
【００４１】
（実施例４）
実施例３の磁気テープＢにおいて、前記式（化５）に代えて前記式（化８）を用いた磁気テープを作製して同様の試験を行った。
【００４２】
（実施例５）
実施例３の磁気テープＡにおいて、前記式（化５）に代えて前記式（化５）と従来公知の防錆剤Ｃ₈ Ｆ₁₇Ｃ₂ Ｈ₄ ＮＨＣ₁₈Ｈ₃₅を重量比で２：１の混合物を用いた磁気テープを作製して同様の試験を行った。
【００４３】
（実施例６）
実施例３の磁気テープＢにおいて、前記式（化５）に代えて前記式（化５）と従来公知の潤滑剤Ｃ₁₇Ｈ₃₃ＣＯＯＣ₂ Ｈ₄ Ｃ₆ Ｆ₁₃を重量比で１：１の混合物を用いた磁気テープを作製して同様の試験を行った。
【００４４】
以上の実施例の試験結果を表１に示す。表中の従来例１、２および３の潤滑剤はそれぞれ前記式（化２）、（化３）および（化４）に示すものである。
【００４５】
【表１】

【００４６】
（表１）より、本発明の含フッ素カルボン酸アミン塩を１種以上含有する潤滑剤層を設けた磁気テープはすべて、高温高湿度の環境下での保存後においても潤滑性が優れていることが確認できた。一方、従来の潤滑剤のみから成る潤滑剤層を設けた磁気テープは高温高湿度の環境下で保存すると、潤滑剤の減少が起こり潤滑性が低下することが明かである。
【００４７】
なお、実施例では前記式（化５）、（化８）および前記式（化５）の物質と従来公知の潤滑剤、防錆剤との混合物について説明したが、下記式（化１１）〜（化１５）の物質、これらの物質と従来公知の潤滑剤、防錆剤との混合物についても同様の効果が得られる。
【００４８】
【化１１】

【００４９】
【化１２】

【００５０】
【化１３】

【００５１】
【化１４】

【００５２】
【化１５】

【００５３】
（実施例７）
つぎに、本発明の第７の実施例について具体的に説明する。本実施例の物質は下記式（化１６）で示されるものである。
【００５４】
【化１６】

【００５５】
前記式（化１６）の物質の分子量は１，７５４であった。前記式（化１６）の物質を前記式（化１）の一般式と比較しながら説明すると、Ｒ¹ が炭素数１８の脂肪族アルキル基で、Ｒ² がフッ素と結合した炭素を８個有するフロロアルキル基で、Ｒ³ が炭素数２の飽和の炭化水素鎖で、Ｒ⁴ が炭素数３の飽和の炭化水素鎖で、Ｒ⁵ がフッ素と結合した炭素を８個有するフロロアルキル基で、ｎが０の２級アミン塩である。
【００５６】
つぎに、前記式（化１６）で示される物質の製造方法を説明する。出発原料は下記式（化１７）で示されるフロロアルキル基付アミンと下記式（化１８）で示される物質である。この下記式（化１８）で示される物質はオクタデシル無水コハク酸と２−（パーフロロ−ｎ−オクチル）エタノールから合成されたものである。
【００５７】
【化１７】

【００５８】
【化１８】

【００５９】
前記式（化１８）で示される原料８１. ７ｇ（０. １０モル）と酢酸エチル１０００mlを撹拌翼を備えた２リットルのフラスコに採取し、１５℃に冷却した後、酢酸エチル４００mlに溶解した前記式（化１７）で示される原料９３. ７ｇ（０. １０モル）を滴下した。滴下終了後、反応溶液を室温に戻して２時間撹拌を続けた。反応終了後、実施例１および２と同様に処理して、無色透明の固体１７０g （融点８０℃）を得た。この無色透明の固体はＩＲ、ＧＰＣおよびＦＤ−ＭＳにより、出発原料および副生成物を含まない前記式（化１６）で示される含フッ素カルボン酸アミン塩であることが判明した。
【００６０】
ＩＲ；カルボン酸の１, ７０５cm^-1の吸収ピーク消滅、カルボン酸アミン塩の１５４０cm^-1の吸収ピーク出現（図５）。
ＧＰＣ；出発原料および副生成物検出されず。
【００６１】
ＦＤ−ＭＳ；ｍ／ｅ １, ７５４に主ピーク有り。
【００６２】
【発明の効果】
以上の説明から明かなように、本発明の含フッ素カルボン酸アミン塩は同一分子内に２個の含フッ素炭化水素末端基、すなわちフロロアルキル末端基、フロロアルケニル末端基、フロロフェニル末端基またはフロロアルキルエーテル末端基と１個の脂肪族炭化水素末端基、すなわち脂肪族アルキル末端基または脂肪族アルケニル末端基とアミノ・カルボキシル基を有する構造であるために、高温高湿度の環境下での保存後においても潤滑性が低下しないという優れた効果を示す。
【図面の簡単な説明】
【図１】 本発明の一実施例の含フッ素カルボン酸アミン塩からなる潤滑剤を設けた磁気記録媒体の断面図である。
【図２】 本発明の別の実施例の含フッ素カルボン酸アミン塩からなる潤滑剤を設けた磁気記録媒体の断面図である。
【図３】 本発明の実施例１の赤外線（ＩＲ）スペクトルチャートである。
【図４】 本発明の実施例２の赤外線（ＩＲ）スペクトルチャートである。
【図５】 本発明の実施例７の赤外線（ＩＲ）スペクトルチャートである。
【符号の説明】
１ 基材フィルム
２ 強磁性膜
３ 潤滑剤層
４ バックコート層
５ 保護膜[0001]
[Industrial application fields]
The present invention relates to a novel fluorine-containing carboxylic acid amine salt useful as a precision machine requiring high-precision lubricity, a lubricant for precision parts, a surfactant, a mold release agent, a rust inhibitor, and the like, and a magnetic recording having the same. It relates to the medium.
[0002]
[Prior art]
With the downsizing and high precision of mechanical devices and parts, the lubrication form of these sliding parts has also shifted from fluid lubrication to boundary lubrication. In particular, in electronic devices and electronic parts such as VTRs and magnetic disks, the use of a ferromagnetic metal thin film for the purpose of improving the recording density requires high-precision lubrication for sliding between the magnetic recording medium and the magnetic head. It has become. For example, with vapor deposition tape and hard disks, there are only a few lubricant layers on the surface of the magnetic layer in order to increase the output by minimizing the spacing loss between the magnetic recording medium and the magnetic head while ensuring durability and reliability. It is formed to have a thickness of nm (several tens of angstroms). Therefore, development of an organic compound having excellent lubricity is an important issue as a material for forming the lubricant layer.
[0003]
As a lubricant for a metal thin film type magnetic recording medium, a long-chain carboxylic acid perfluoroalkylamine salt compound represented by the following formula (Chemical Formula 2) or a fluoroalkyl ether group-containing aliphatic carboxylic acid represented by the following formula (Chemical Formula 3) Since an acid or an aliphatic carboxylic acid having a fluoroalkyl group represented by the following formula (Chemical Formula 4) is excellent in compatibility with a metal thin film, proposals have been made (Japanese Patent Laid-Open Nos. 4-274018 and 4- 270243).
[0004]
[Chemical 2]

[0005]
[Chemical 3]

[0006]
[Formula 4]

[0007]
[Problems to be solved by the invention]
However, the lubricants represented by the above formulas (Chemical Formula 2), (Chemical Formula 3), and (Chemical Formula 4) are transferred to the back coat surface when the magnetic tape is stored in a high temperature and high humidity environment. There was a problem that the amount of lubricant on the surface decreased and the lubricity decreased. This decrease in lubricity is more prominent as deterioration in still durability than in repeated running after storage.
[0008]
The present invention solves the above-described conventional problems, and an object thereof is to provide a substance that does not deteriorate lubricity even after storage in a high-temperature and high-humidity environment, and a magnetic recording medium provided with the substance. .
[0009]
[Means for Solving the Problems]
The fluorine-containing carboxylic acid amine salt of the present invention for achieving the above object is represented by the above general formula (Formula 1).
[0010]
In Formula (Formula 1), R ¹ is represents an aliphatic alkyl group or an aliphatic alkenyl group with a carbon number of 10 to 24, R ² is a fluoroalkyl group having a carbon number is 6 to 18, carbon atoms 6 18 represents a fluoroalkenyl group having 6 to 12 carbon atoms, or a fluoroalkyl ether group having 5 to 30 carbon atoms, and R ³ and R ⁴ are saturated or unsaturated having 1 to 10 carbon atoms. a hydrocarbon chain, R ⁵ is a fluoroalkyl group having a carbon number is 6 to 18 or carbon atoms showed 6-18 of Furoroarukeniru group, R ⁶ and R ⁸ are saturated having 1 to 10 carbon atoms or an a hydrocarbon chain, saturated, R ⁷ and R ⁹ are a fluoroalkyl group having a carbon number is 6 to 18, or is preferably carbon number is 6-18 Furoroarukeniru group.
[0011]
Next, in the magnetic recording medium of the present invention, a fluorinated carboxylic acid represented by the above general formula (Chemical Formula 1) is provided on a base film with a ferromagnetic film directly or via a protective film. A lubricant layer containing an amine salt is provided.
[0012]
In the above, the amount of the lubricant in the lubricant layer is preferably in the range of 0.1 to 50 mg per 1 m ^{2 of} the surface.
In the above, the lubricant preferably contains 90% by weight or more of the fluorine-containing carboxylic acid amine salt represented by the general formula (Formula 1).
[0013]
In the above, the lubricant is a composition containing 50% by weight or more of the fluorine-containing carboxylic acid amine salt represented by the general formula (Formula 1), and a lubricant and a rust preventive agent of other fluorine-containing compounds. Is preferred. For example, C ₁₇ H ₃₃ COOC ₂ H ₄ C ₆ F ₁₃ is used as a lubricant for other fluorine-containing compounds, and C ₈ F ₁₇ C ₂ H ₄ NHC ₁₈ is used as a rust preventive for other fluorine-containing compounds. H ₃₅ etc.
[0014]
Moreover, in the above, it is preferable that the lubricant and rust preventive agent of other fluorine-containing compounds are liquid fluorine-containing compounds.
In the above, the protective film is at least one thin film selected from an amorphous carbon thin film having a film thickness of 5 to 50 nm, a graphite carbon thin film, a diamond carbon thin film or a mixed state thereof, and a laminated carbon thin film. Is preferred.
[0015]
In the above, it is preferable that the base film is at least one film selected from polyethylene terephthalate, polyethylene 2,6-naphthalate, and polyimide having a film thickness of 3 to 30 μm.
[0016]
In the above, the ferromagnetic film is preferably a Co—Ni—O-based alloy oxide film. The thickness is preferably in the range of 80 to 300 nm (800 to 3000 angstroms).
[0017]
Moreover, in the above, it is preferable that the backcoat layer is formed in the back surface of a base film.
In the above, the back coat layer is preferably a composition containing a binder resin and a filler substance.
[0018]
In the above, the binder resin is preferably at least one resin selected from polyester elastomer and nitrocellulose, and the filler material is preferably at least one particle selected from calcium carbonate and carbon black.
[0019]
[Action]
The fluorine-containing carboxylic acid amine salt of the present invention has two fluorine-containing hydrocarbon end groups, that is, a fluoroalkyl end group, a fluoroalkenyl end group, a fluorophenyl end group or a fluoroalkyl ether end group and one fat in the same molecule. It has a structure having an aliphatic hydrocarbon end group, that is, an aliphatic alkyl end group or an aliphatic alkenyl end group and an amino carboxyl group. Here, since the fluorine-containing hydrocarbon terminal group is oleophobic, it has poor affinity with a backcoat layer composed of a hydrocarbon-based polymer. On the other hand, lipophilic aliphatic hydrocarbon end groups have a high affinity with the backcoat layer, but if there are more fluorine-containing hydrocarbon end groups in the same molecule than the aliphatic hydrocarbon end groups, Becomes more oleophobic and less compatible with the backcoat layer. For this reason, the fluorinated carboxylic acid amine salt is suppressed from being transferred to the backcoat layer, that is, from the surface of the magnetic layer, and the magnetic tape does not deteriorate over time.
[0020]
By the way, the amino / carboxyl group strongly adheres to the surface of the metal thin film or the surface of the protective film and the surface of the magnetic head. Further, the fluorine-containing hydrocarbon end groups are exposed on the surface and contribute to lowering the energy of the surface, thereby forming a non-adhesive surface. Furthermore, the aliphatic hydrocarbon end group is a flexible carbon-carbon bond chain, and therefore exhibits good lubricity. Then, due to the synergistic effect of these terminal groups, excellent lubricity is exhibited in all environments from a low humidity environment (eg, 5 ° C., 5% RH) to a high humidity environment (eg, 40 ° C., 80% RH).
[0021]
【Example】
Example 1
The first embodiment of the present invention will be specifically described below. The substance of this example is represented by the following formula (Formula 5).
[0022]
[Chemical formula 5]

[0023]
The compound of the above formula (Formula 5) has a molecular weight of 1,603. The above substance will be described in comparison with the general formula of the above formula (Chemical Formula 1). R ¹ is an aliphatic alkyl group having 18 carbon atoms and R ² is a fluoroalkyl ether group having 11 carbons bonded to fluorine. , A fluoroalkenyl group in which R ³ is a hydrocarbon chain having 1 carbon atom, R ⁴ is a saturated hydrocarbon chain having 10 carbon atoms, R ⁵ has 9 carbons bonded to fluorine, and has ether as a bonding group And n is 1.
[0024]
Next, a method for producing the substance represented by the above formula (Formula 5) will be described. The starting materials are an amine with a fluoroalkenyl group represented by the TG formula (Formula 6) and a substance represented by the following formula (Formula 7).
[0025]
[Chemical 6]

[0026]
[Chemical 7]

[0027]
The substance represented by the above formula (Chem. 7) is synthesized from octadecyl succinic anhydride and 1H, 1H-perfluoro-2,5,8-trimethyl-3,6,9-trioxaundecan-1-ol. is there. That is, 100.0 g (0.10 mol) of the raw material represented by the above formula (Chemical Formula 7) and 1000 ml of ethyl acetate were collected in a 2 liter flask equipped with a stirring blade, cooled to 15 ° C., and then added to 400 ml of ethyl acetate. 66.4 g (0.11 mol) of the dissolved raw material represented by Chemical Formula 6 was added dropwise. After completion of the dropping, the reaction solution was returned to room temperature and stirred for 2 hours. After completion of the reaction, the reaction solution was cooled to 0 ° C. to recrystallize the reaction product, and the unreacted fluoroalkenyl-containing amine was removed by filtration under reduced pressure to obtain 115 g of a white solid having a melting point of 72 ° C. This white solid was analyzed by infrared spectroscopic analysis (IR), gel permeation chromatography (GPC), and organic mass spectrometry (FD-MS), and contained a fluorine-containing carboxylic acid amine salt represented by Chemical Formula 5 that does not contain any starting materials and by-products. It was confirmed that.
[0028]
IR; absorption peak disappearance of carboxylic acids of 1, 705cm ^-1, the absorption peak appearance of 1540 cm ^-1 of the carboxylic acid amine salt (Figure 3).
GPC; no starting materials and by-products detected.
[0029]
FD-MS; Main peak at m / e 1,603.
(Example 2)
Next, a second embodiment of the present invention will be specifically described. The substance of this example is represented by the following formula (Formula 8).
[0030]
[Chemical 8]

[0031]
The compound of the above formula (Formula 8) had a molecular weight of 1,316. The substance of the formula (Chemical Formula 8) will be described in comparison with the general formula of the Formula (Chemical Formula 1). R ¹ is an aliphatic alkenyl group having 18 carbon atoms, and R ² has 6 carbons bonded to fluorine. A fluoroalkyl group, wherein R ³ is an unsaturated hydrocarbon chain having 11 carbon atoms, R ⁴ is a saturated hydrocarbon chain having 3 carbon atoms, and R ⁵ is a fluoroalkyl group having 8 carbons bonded to fluorine. , N is 0.
[0032]
Next, a method for producing the substance represented by the above formula (Formula 8) will be described. The starting materials are an amine with a fluoroalkyl group represented by the following formula (Formula 9) and a substance represented by the following formula (Formula 10). The substance represented by the following formula (Formula 10) is synthesized from 2-octadecenyl succinic anhydride and 11- (perfluoro-n-hexyl) -10-undecenol.
[0033]
[Chemical 9]

[0034]
Embedded image

[0035]
83.9 g (0.10 mol) of the raw material represented by the above formula (Chemical Formula 10) and 1000 ml of ethyl acetate were collected in a 2 liter flask equipped with a stirring blade, cooled to 15 ° C., and dissolved in 400 ml of ethyl acetate. 52.5 g (0.11 mol) of the raw material represented by the above formula (Chemical Formula 9) was added dropwise. After completion of the dropping, the reaction solution was returned to room temperature and stirred for 2 hours. After completion of the reaction, the reaction solution was cooled to −20 ° C. to solidify and precipitate the reaction product, and the unreacted fluoroalkyl group-containing amine was removed by low-temperature filtration to obtain 88 g of a colorless and transparent liquid. This colorless and transparent liquid was confirmed by IR, GPC and FD-MS to be a fluorine-containing carboxylic acid amine salt represented by the chemical formula 8 containing no starting materials and by-products.
[0036]
IR: Absorption peak disappearance at 1,705 cm ⁻¹ of carboxylic acid, absorption peak appearance at 1540 cm ⁻¹ of carboxylic acid amine salt (FIG. 4).
GPC; no starting materials and by-products detected.
[0037]
FD-MS; Main peak at m / e 1,316.
(Example 3)
Next, the magnetic recording medium of the present invention will be described. FIG. 1 is a sectional view of a magnetic recording medium according to an embodiment of the present invention. In FIG. 1, 1 is at least one base film selected from polyethylene terephthalate, polyethylene 2,6-naphthalate and polyimide having a film thickness of 3 to 30 μm. 2 is a ferromagnetic film such as a Co—Ni—O-based alloy oxide plating film, 3 is a lubricant layer formed of the fluorine-containing carboxylic acid amine salt of the present invention, and 4 is a backcoat layer. The back coat layer 4 is made of, for example, polyester elastomer (polybutylene terephthalate-polytetrafluoroether copolymer) (Toyobo "Byron") 30% by weight, nitrocellulose 20% by weight, calcium carbonate fine particles 30% by weight, and carbon black 20 It is preferably composed of% by weight, a thickness in the range of 3 to 10 μm, and a surface resistance of 10 ¹⁰ ohm / cm ² or less.
[0038]
Next, FIG. 2 shows an example in which a protective film 5 is provided between the ferromagnetic film 2 and the lubricant layer 3. Providing the protective film 5 can prevent the ferromagnetic film 2 from being oxidized and can be used stably for a long period of time. 1 and 2, an intermediate layer may be provided on the surface of the base film 1 in order to increase the adhesion between the base film 1 and the ferromagnetic film 2.
[0039]
Specific examples will be described below.
In the base film 1 of the magnetic recording medium of this example, the granular projections (average height 7 nm (70 angstrom), diameter 1 μm) due to silica fine particles added in the polyethylene terephthalate film are several per 100 μm ^{2 of the} surface. There was used a polyester film in which relatively large protrusions due to fine particles caused by residual polymerization catalyst were reduced as much as possible. On its surface, and the colloidal silica particles with an average diameter of 15 nm (0.99 Å) as a core, an intermediate layer such a steep mountain-like projections for the ultraviolet cured epoxy resin and the binder is ² per 1 × 10 ⁷ cells 1mm I let you. The thickness of the intermediate layer was about 15 μm. Then, a Co—Ni ferromagnetic film 2 (Ni content: 20 atm%, film thickness: 100 nm (1000 angstroms)) was provided on the nonmagnetic support by continuous vacuum oblique deposition in the presence of a small amount of oxygen. The oxygen content in the ferromagnetic film was 5% in atomic fraction.
[0040]
Next, the lubricant layer 3 is formed by applying the fluorine-containing carboxylic acid amine salt represented by the above formula (Chemical Formula 5) on the above ferromagnetic film so as to be 10 mg / m ^2. The tape A was cut to a predetermined width to produce a magnetic tape A. Further, a diamond-like carbon protective film having a thickness of 5 nm (50 angstroms) was formed on the ferromagnetic film by plasma CVD, and then magnetic tape B was produced in the same manner as magnetic tape A. The magnetic tape was stored for 1 week in an environment of 40 ° C. and 90% RH, and then the fluorine residual rate before and after storage on the magnetic layer surface was examined by X-ray photoelectron spectroscopy (ESCA). In addition, the output characteristics at the time of still reproduction are measured by putting it on a commercially available video deck in an environment of 23 ° C., 10% RH and 40 ° C., 80% RH, and the RF output is reduced by 3 dB from the initial value or the output fluctuation. The still endurance time until the occurrence of stagnation was determined.
[0041]
(Example 4)
In the magnetic tape B of Example 3, a magnetic tape using the above formula (Chemical Formula 8) instead of the formula (Chemical Formula 5) was produced, and the same test was performed.
[0042]
(Example 5)
In the magnetic tape A of Example 3, in place of the formula (Chemical Formula 5), the formula (Chemical Formula 5) and a conventionally known rust preventive agent C ₈ F ₁₇ C ₂ H ₄ NHC ₁₈ H ₃₅ in a weight ratio of 2: 1. A magnetic tape using the above mixture was prepared and subjected to the same test.
[0043]
(Example 6)
In the magnetic tape B of Example 3, the above formula (Chemical Formula 5) and the conventionally known lubricant C ₁₇ H ₃₃ COOC ₂ H ₄ C ₆ F ₁₃ were mixed at a weight ratio of 1: 1 instead of the above Formula (Chemical Formula 5). A magnetic tape using the mixture was prepared and subjected to the same test.
[0044]
The test results of the above examples are shown in Table 1. The lubricants of Conventional Examples 1, 2, and 3 in the table are those shown in the above formulas (Chemical Formula 2), (Chemical Formula 3), and (Chemical Formula 4), respectively.
[0045]
[Table 1]

[0046]
From Table 1, all magnetic tapes provided with a lubricant layer containing one or more fluorine-containing carboxylic acid amine salts of the present invention are excellent in lubricity even after storage in a high temperature and high humidity environment. I was able to confirm. On the other hand, it is clear that a magnetic tape provided with a lubricant layer made of only a conventional lubricant is stored in a high-temperature and high-humidity environment, resulting in a decrease in the lubricant and a decrease in lubricity.
[0047]
In addition, although the Example demonstrated the mixture of the substance of said Formula (Chemical Formula 5), (Chemical Formula 8) and the said Formula (Chemical Formula 5) and a conventionally well-known lubricant and a rust preventive agent, following formula (Chemical Formula 11)- The same effect can be obtained with the chemical formula (15) and mixtures of these substances with conventionally known lubricants and rust inhibitors.
[0048]
Embedded image

[0049]
Embedded image

[0050]
Embedded image

[0051]
Embedded image

[0052]
Embedded image

[0053]
(Example 7)
Next, a seventh embodiment of the present invention will be specifically described. The substance of this example is represented by the following formula (Formula 16).
[0054]
Embedded image

[0055]
The molecular weight of the substance represented by the formula (Formula 16) was 1,754. The substance of the formula (Chem. 16) will be described in comparison with the general formula of the formula (Chem. 1). R ¹ is an aliphatic alkyl group having 18 carbon atoms, and R ² has 8 carbons bonded to fluorine. A fluoroalkyl group, wherein R ³ is a saturated hydrocarbon chain having 2 carbon atoms, R ⁴ is a saturated hydrocarbon chain having 3 carbon atoms, and R ⁵ is a fluoroalkyl group having 8 carbons bonded to fluorine; A secondary amine salt in which n is 0.
[0056]
Next, a method for producing the substance represented by the above formula (Formula 16) will be described. The starting materials are an amine with a fluoroalkyl group represented by the following formula (Chemical Formula 17) and a substance represented by the following formula (Chemical Formula 18). The substance represented by the following formula (Chemical Formula 18) is synthesized from octadecyl succinic anhydride and 2- (perfluoro-n-octyl) ethanol.
[0057]
Embedded image

[0058]
Embedded image

[0059]
81.7 g (0.10 mol) of the raw material represented by the above formula (Chemical Formula 18) and 1000 ml of ethyl acetate were collected in a 2 liter flask equipped with a stirring blade, cooled to 15 ° C., and dissolved in 400 ml of ethyl acetate. 93.7 g (0.10 mol) of the raw material represented by the above formula (Chemical Formula 17) was added dropwise. After completion of the dropping, the reaction solution was returned to room temperature and stirred for 2 hours. After completion of the reaction, the same treatment as in Examples 1 and 2 was performed to obtain 170 g of a colorless and transparent solid (melting point: 80 ° C.). This colorless and transparent solid was found by IR, GPC and FD-MS to be a fluorine-containing carboxylic acid amine salt represented by the above formula (Formula 16) containing no starting materials and by-products.
[0060]
IR: Absorption peak disappearance at 1,705 cm ⁻¹ of carboxylic acid, absorption peak appearance at 1540 cm ⁻¹ of carboxylic acid amine salt (FIG. 5).
GPC; no starting materials and by-products detected.
[0061]
FD-MS; Main peak at m / e 1,754.
[0062]
【The invention's effect】
As is clear from the above description, the fluorine-containing carboxylic acid amine salt of the present invention has two fluorine-containing hydrocarbon terminal groups in the same molecule, that is, a fluoroalkyl terminal group, a fluoroalkenyl terminal group, a fluorophenyl terminal group or a fluorocarbon terminal group. After storage in a high temperature and high humidity environment due to the structure having an alkyl ether end group and one aliphatic hydrocarbon end group, ie, an aliphatic alkyl end group or an aliphatic alkenyl end group and an amino carboxyl group In this case, the excellent effect that the lubricity does not deteriorate is exhibited.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a magnetic recording medium provided with a lubricant comprising a fluorine-containing carboxylic acid amine salt according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of a magnetic recording medium provided with a lubricant comprising a fluorine-containing carboxylic acid amine salt according to another embodiment of the present invention.
FIG. 3 is an infrared (IR) spectrum chart of Example 1 of the present invention.
FIG. 4 is an infrared (IR) spectrum chart of Example 2 of the present invention.
FIG. 5 is an infrared (IR) spectrum chart of Example 7 of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Base film 2 Ferromagnetic film 3 Lubricant layer 4 Backcoat layer 5 Protective film

Claims (7)

A fluorine-containing carboxylic acid amine salt represented by the following general formula (Formula 1).

However, R ¹ is represents an aliphatic alkyl group or an aliphatic alkenyl group having 6 to 30 carbon atoms, R ² is a fluoroalkyl group having a carbon number of 3 to 30, Furoroarukeniru group having 6 to 18 carbon atoms A fluorophenyl group having 6 to 18 carbon atoms, or a fluoroalkyl ether group having 5 to 50 carbon atoms, R ³ and R ⁴ represent a saturated or unsaturated hydrocarbon chain having 1 to 20 carbon atoms, and R ⁵ fluoroalkyl group having a carbon number of 3 to 30 or a carbon number represents the Furoroarukeniru group of 3 to 30, n is 0 or 1, X is hydrogen ^{or, - (R 8) -R 9} ( wherein, R ⁶ and R ⁸ represents a saturated or unsaturated hydrocarbon chain having 1 to 20 carbon atoms, R ⁷ and R ⁹ are a fluoroalkyl group having a carbon number of 3 to 30, or carbon number is 3-30 fluoroalkyl Represents an alkenyl group. The Formula (1), R ¹ represents an aliphatic alkyl group or an aliphatic alkenyl group with a carbon number of 10 to 24, R ² is a fluoroalkyl group having a carbon number is 6 to 18, carbon atoms 6 to 18 A fluoroalkenyl group having 6 to 12 carbon atoms, or a fluoroalkyl ether group having 5 to 30 carbon atoms, wherein R ³ and R ⁴ are saturated or unsaturated carbon atoms having 1 to 10 carbon atoms. It represents hydrogen chain, R ⁵ is a fluoroalkyl group having a carbon number is 6 to 18 or carbon atoms showed 6-18 of Furoroarukeniru group, R ⁶ and R ⁸ are saturated or unsaturated having 1 to 10 carbon atoms hydrocarbon chain indicates, R ⁷ and R ⁹ are a fluoroalkyl group having a carbon number is 6 to 18, or a fluorine-containing carboxylic acid amine salt according to claim 1 carbon number is 6-18 Furoroarukeniru group .   A ferromagnetic film is provided on a base film, and a lubricant layer containing the fluorine-containing carboxylic acid amine salt represented by the above general formula (Formula 1) is provided directly or via a protective film on the ferromagnetic film. Magnetic recording media. The magnetic recording medium according to claim 3, wherein the amount of the lubricant in the lubricant layer is in the range of 0.1 to 50 mg per 1 m ^{2 of} the surface.   4. The lubricant according to claim 3, wherein the lubricant is a composition comprising 50% by weight or more of the fluorine-containing carboxylic acid amine salt represented by the general formula (Chemical Formula 1), and a lubricant and a rust preventive of other fluorine-containing compounds. Magnetic recording medium.   6. The magnetic recording medium according to claim 5, wherein the other fluorine-containing compound lubricant and rust preventive agent are liquid fluorine-containing compounds.   The protective film is at least one thin film selected from an amorphous carbon thin film having a film thickness of 5 to 50 nm, a graphite-like carbon thin film, a diamond-like carbon thin film or a mixed state thereof, and a laminated carbon thin film. Magnetic recording medium.

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