JP2004359834A - Stain resistance imparting agent and stain resistant article using the same - Google Patents

Abstract

A coating film formed from a stain resistance imparting agent has a pencil hardness of 5B or more, a contact angle with water of 80 ° or more, and a contact angle with oleic acid, triolein and squalene of 10 ° or less. Stain resistance imparting agent. As the composition, it contains a (meth) acrylic copolymer (A) containing a (meth) acrylate having a water-repellent group containing no silicon and fluorine as a copolymerization component or a composite of the (meth) acrylic copolymer and inorganic oxide fine particles. . It preferably further contains an organic compound having a (meth) acryloyl group curable by an active energy ray.
[Effect] It is possible to form a coating film having excellent hardness, scratch resistance, transparency, low curl and the like at the same time as excellent fingerprint stain resistance and sebum stain resistance. It can be suitably used for a wide range of applications such as touch panel resistance, displays, mobile phone housings, and optical disks.

Description

（式中、Ｘ及びＹは、それぞれ独立に、酸素原子、イオウ原子又はイミノ基のいずれかである）。
【００３２】
式（１）に示す官能基は、分子間において水素結合による過度の凝集力を発生させ、機械的強度、基材への密着性、耐熱性等を付与させる効果があるとともに、無機酸化物表面とラジカル重合性官能基との間のスペーサーとしても働く。具体的には、下記の式（２）の官能基を挙げることができる。
−ＯＣＯＮＨ−、−ＳＣＯＮＨ−、−ＳＣＳＮＨ−、−ＯＣＳＮＨ−、−ＮＨＣＯＮＨ−、−ＮＨＣＳＮＨ− ・・・・・（２）
これらの基のうち、熱安定性や合成の容易さの観点から、−ＯＣＯＮＨ−、−ＳＣＯＮＨ−が特に好ましい。
また、この化合物は同時にチオエーテル基を有する有機化合物であっても良い。チオエーテル基も、シリカ表面とラジカル重合性官能基または特定の極性官能基との間のスペーサーとして働き、過度の凝集を抑える効果があるものと思われる。
【００３３】
無機酸化物と結合しうるシランカップリング剤の官能基としては、シラノール基を生成しうる基であるアルコキシシリル基が特に好ましい。アルコキシシリル基としては、モノアルコキシシリル基、ジアルコキシシリル基、トリアルコキシシリル基を挙げることができるが、中でもトリメトキシシリル基やトリエトキシシリル基などの低級アルコールのトリアルコキシシリル基が反応性を考えると特に好ましい。分子中における、これらの基の位置は、重合性不飽和基と反対側の分子末端にあることが好ましい。また１分子中の基の数は１〜３個であることが好ましく、特に好ましいのは１個である。
【００３４】
シラノール基またはシラノール基生成単位は、縮合反応または加水分解に続いて起きる縮合反応によって、無機酸化物微粒子と結合する生成単位である。このような化合物（Ｄ−１）の好ましい例をいくつか例示すると、
▲１▼ＯＨ基を有する（メタ）アクリレート化合物とＮＣＯ基を有するトリアルコキシシランとが−ＯＣＯＮＨ−結合で接続された化合物、
▲２▼ＳＨ基を有するトリアルコキシシラン化合物とジイソシアネートの一方のＮＣＯ基を−ＮＨＣＯＳ−結合で接続し、残りのＮＣＯ基にＯＨ基を有する（メタ）アクリレート化合物を作用させ、−ＮＨＣＯＯ−結合で接続した化合物、
▲３▼ＮＣＯ基を有する（メタ）アクリレート化合物と、ＳＨ基を有するトリアルコキシシランとが−ＮＨＣＯＳ−結合で接続された化合物、
▲４▼分子内に２個以上の（メタ）アクリロイル基を含有する化合物、とＳＨ基を有するトリアルコキシシランとが、ＳＨ基の（メタ）アクリロイル基へのマイケル付加反応により生成するチオエーテル結合で接続された化合物、
▲５▼α、ω−ヒドロキシ末端ポリアルキレングリコールのモノ（メタ）アクリル酸エステルと、ＮＣＯ基を有するシランカップリング剤とを反応させた化合物、
等を挙げることができるが、これらに限定はされない。
【００３５】
ＯＨ基を有する（メタ）アクリレートとしては、例えばモノ（メタ）アクリレート（例えば、ヒドロキシエチルアクリレート、ヒドロキシエチルメタクリレート、ヒドロキシプロピルアクリレート、ヒドロキシプロピルメタクリレート等）、ジ（メタ）アクリレート（例えば、グリセリンジ（メタ）アクリレート、トリメチロールプロパンジ（メタ）アクリレート等）、トリ〜ポリ（メタ）アクリレート（例えば、ペンタエリスリトールトリアクリレート、ジペンタエリスリトールトリ〜ペンタアクリレート、ジトリメチロールプロパントリアクリレート等）を例示することができる。
【００３６】
ＮＣＯ基を有するトリアルコキシシラン化合物としては、トリエトキシシリルプロピルイソシアネート（例えば信越化学工業株式会社よりＫＢＥ９００７の商品名で入手可能）、トリメトキシシリルプロピルイソシアネート、あるいはトリメトキシシリルプロピルメルカプタン（例えば信越化学工業株式会社よりＫＢＭ８０３の商品名で、東レダウコーニングシリコン株式会社よりＳＨ６０６２の商品名で入手可能）等のトリアルコキシシリルアルキルメルカプタンとジイソシアネート（例えばイソホロンジイソシアネート、ヘキサメチレンジイソシアネート、ＭＤＩ、ＴＤＩ等）の一方のＮＣＯ基とをチオウレタン結合で接続した化合物等を例示することができる。
【００３７】
ＯＨ基とＮＣＯ基との反応による−ＯＣＯＮＨ−結合の生成法は、各化合物をＮＣＯ基／ＯＨ基≦１の割合で配合し、６０〜１００℃で１時間から２０時間混合攪拌することにより得られる。本反応においては、反応中の（メタ）アクロイリル基による重合等を防止するために、例えばハイドロキノン、ハイドロキノンモノメチルエーテル、カテコール、ｐ−ｔ−ブチルカテコール、フェノチアジンなどの重合禁止剤を使用するのが好ましく、その量は反応混合物に対して、０．０１〜１重量％、好ましくは０．０５〜０．５重量％である。また反応を促進するために、例えばジラウリン酸ジ−ｎ−ブチル錫、ジアザビシクロオクタン（通常ＤＡＢＣＯと略す）のような公知の反応触媒を添加しても良い。さらに本反応は例えば、メチルエチルケトン、メチルイソブチルケトン等のケトン系溶媒、エチレングリコールジエチルエーテル、ジエチレングリコールジメチルエーテル等のエーテル系溶媒、酢酸エチル、酢酸ブチル等のカルボン酸エステル系溶媒、キシレン、トルエン等の芳香族炭化水素溶媒等、イソシアネート基を反応しうる基を含まない溶媒中、または、同時に、分子内に３個以上の（メタ）アクリロイル基を有する多官能アクリレートの存在下、行うことができる。
【００３８】
ＮＣＯ基を有する（メタ）アクリレート化合物としては、β−イソシアネートエチル（メタ）アクリレート（メタクリレートはカレンズＭＯＩの商品名で昭和電工株式会社より入手可能）、または、ＯＨ基を有する（メタ）アクリレート類と、ジイソシアネート（例えばイソホロンジイソシアネート、ヘキサメチレンジイソシアネート、ＭＤＩ、ＴＤＩ等）の一方のＮＣＯ基とをウレタン結合で接続した化合物等を例示することができる。
【００３９】
ＳＨ基を有するトリアルコキシシラン化合物としては、例えばトリメトキシシリルプロピルメルカプタン（例えば信越化学工業株式会社よりＫＢＭ８０３の商品名で、東レダウコーニングシリコン株式会社よりＳＨ６０６２の商品名で入手可能）等を例示することができる。
【００４０】
ＮＣＯ基とＳＨ基との反応による−ＮＨＣＯＳ−結合の生成法は、ＮＣＯ基とＯＨ基との反応による−ＮＨＣＯＯ−結合生成と同様の方法でおこなうことができる。
α、ω−ヒドロキシ末端ポリアルキレングリコールのモノ（メタ）アクリル酸エステル化合物としては、ポリエチレングリコールモノ（メタ）アクリレート、ポリプロピレングリコールモノ（メタ）アクリレート、ポリテトラメチレングリコールモノ（メタ）アクリレート、ポリ（エチレン／プロピレン）グリコールモノ（メタ）アクリレート、ポリ（エチレン／テトラメチレン）グリコールモノ（メタ）アクリレート等を例示することができる。
【００４１】
α、ω−ヒドロキシ末端ポリアルキレングリコールのモノ（メタ）アクリル酸エステル化合物とＮＣＯ基を有するトリアルコキシシリル化合物の反応はＮＣＯ基とＯＨ基との反応による−ＮＨＣＯＯ−結合生成と同様の方法でおこなうことができる。
【００４２】
（Ｄ−１）と無機酸化物微粒子の反応、結合については、先に説明したメルカプトシランと無機酸化物微粒子の場合と同様に行うことができる。水や触媒の使用方法、使用量なども同様である。
【００４３】
これとは別に、（Ｄ−１）を合成しうる成分のうち、あらかじめ式（１）または（２）に示す結合基を生成しうる官能基を有するアルコキシシリル化合物を先に無機酸化物微粒子に反応させた後、他の化合物を反応させ、重合性不飽和基および、式（１）または（２）に示す結合基を導入する方法もある。式（１）のうち、アルコキシシリル基を有する化合物として、ＳＨ基を有するトリアルコキシシラン化合物は、あらかじめ無機酸化物微粒子に反応させることが可能である。
【００４４】
例えば、ＳＨ基を有するトリアルコキシシランを無機酸化物に反応させ、その後ＳＨ基を、ジイソシアネート化合物と反応させ、一方のＮＣＯ基を用いて−ＮＨＣＯＳ−結合で接続し、残りのＮＣＯ基にＯＨ基を有する（メタ）アクリレート化合物を作用させ、−ＮＨＣＯＯ−結合で接続させる方法で、先の▲３▼の方法と同様の構造を得ることができる。
【００４５】
また、ＳＨ基を有するトリアルコキシシランを無機酸化物に反応させ、その後ＮＣＯ基を有する（メタ）アクリレート化合物および／または（メタ）アクリルアミド化合物と反応させることで、先の▲４▼と同様の構造を得ることができる。
【００４６】
無機酸化物微粒子と（Ｄ−１）の反応比は、重量比で通常、９０／１０〜５／９５、好ましくは８０／２０〜１０／９０である。無機酸化物微粒子／（Ｄ−１）＞９０／１０であると、無機酸化物の表面保護が不十分で好ましくなく、一方、無機酸化物微粒子／（Ｄ−１）＜５／９５であると、アルコキシシラン自身の重合、架橋による分散状態の不安定化、著しい粘度上昇等を起こすので好ましくない。また、（Ｄ−１）の分子量は３００以上であることが望ましい。３００以下であると、保護コロイドを生成する効果が小さかったり、シランカップリング剤自身の縮合が起こり、架橋等による凝集、ゲル化を起こしやすいので好ましくない。
【００４７】
反応は室温から１００℃、１〜１００時間、好ましくは室温で４時間以上反応の後、室温〜７０℃で１〜１０時間加熱し、反応を進行させる。また副反応を抑えるため、溶媒で反応系を希釈しても良い。用いられる溶媒としては加水分解物であるシランアルコキシドや水、触媒との相溶性があるものが好ましく、例えば、メタノール、エタノール、イソプロパノール、イソブタノール等のアルコール類、アセトン、メチルエチルケトン、メチルイソブチルケトン等のケトン類、ＴＨＦ、ジオキサン等のエーテル類、プロピレングリコールモノメチルエーテル等のＯＨ含有エーテル類等を挙げることができる。
【００４８】
また、（Ｄ−１）の一部（重量で５０％未満）を他のシランカップリング剤で置き換えても良い。他のシランカップリング剤としては、公知の各種市販シランカップリング剤の他、ラジカル重合性官能基を有しない、ポリアルキレングリコール構造を有するシランカップリング剤、カルボン酸基またはカルボン酸エステル基を有するシランカップリング剤、脂環構造を有するシランカップリング剤、枝分かれ構造を有するかさ高いアルコールとＮＣＯ基を有するアルコキシシリル基との反応により得られるシランカップリング剤等を例示することができる。
【００４９】
これらとは別に、（Ｄ）の側鎖が、下記（３）式で示されるシリルエーテル基である、重合性官能基を有するポリマーが結合した無機酸化物微粒子を用いることができる。
−Ｏ−Ｓｉ−Ｒ−Ｓ−Ｐｏｌｙ ・・・・・（３）
但し、Ｒは炭素原子数２〜１０の分岐を有していてもよいアルキレン基であり、Ｐｏｌｙは少なくとも１個の（メタ）アクリロイル基を有するポリマーユニットである。
前記無機酸化物微粒子の製法は特に限定されるものではないが、以下の方法により製造するのが好ましい。
（第１の方法）
まず、メルカプト基含有シランカップリング剤と無機酸化物微粒子を加水分解縮合し、メルカプト基を有する無機酸化物微粒子を合成する（第１−１の工程）。
【００５０】
前記無機酸化物微粒子としては、例えば水及び各種の有機溶媒、又はこれらの混合溶媒を分散媒とし、粒子径が１〜１００ｎｍの無機酸化物微粒子を、その固形分として１０〜４０％含有する無機酸化物微粒子が好ましい。有機溶媒や無機酸化物微粒子の具体例は先に述べたものと同様である。
【００５１】
メルカプト基含有シランカップリング剤と無機酸化物微粒子との加水分解縮合反応は、この混合物に水を添加することにより行われる。メルカプト基含有シランカップリング剤のアルコキシシリル基が水で加水分解し、シラノール基を生成し、このシラノールと無機酸化物微粒子表面のＯＨ基との間で縮合反応が起こり、メルカプト基を表面に有する無機酸化物微粒子が得られる。水の添加量はメルカプト基含有シランカップリング剤のアルコキシシリル基が理論量として１００％加水分解しうる量以上の量であれば良く、１００〜３００％相当量、好ましくは１００〜２００％相当量を添加する。
【００５２】
この加水分解反応を促進するため、加水分解触媒を反応系に添加することができる。加水分解反応としては、例えば、アセチルアセトンアルミニウム、ホウ酸トリブトキシド、塩酸、酢酸、硝酸、マレイン酸、フマル酸、シュウ酸、ジブチルスズジオクテート、ｐ−トルエンスルホン酸、およびこれらの混合物を使用することができる。その使用量はメルカプト基含有シランカップリング剤１００重量部に対して、０．１〜５重量部、好ましくは０．５〜５重量部である。
【００５３】
反応は２０〜１００℃、１〜１００時間、好ましくは２０〜２５℃で４時間以上反応の後、４０〜７０℃で１〜１０時間加熱し、反応を進行させる。また、副反応を抑えるため、溶媒で反応系を希釈しても良い。用いられる溶媒としては用いる水、触媒と相性の良いものが好ましく、例えば、メタノール、エタノール、イソプロパノール、イソブタノール、等のアルコール類、アセトン、メチルエチルケトン、メチルイソブチルケトン等のケトン類、テトラヒドロフラン、ジオキサン等のエーテル類、プロピレングリコールモノメチルエーテル等の水酸基含有エーテル類等を挙げることができる。
反応系におけるメルカプト基含有シランカップリング剤と無機酸化物微粒子（固形分）との重量比は、０．１／９９．９〜１０／９０であることが好ましく、１／９９〜５／９５であることがより好ましい。メルカプト基含有シランカップリング剤の重量比率が０．１未満であると、無機酸化物微粒子と結合するメルカプト基量が少なくなり、エポキシ基を含有する重合体と結合する部位が少なくなるため、重合体との無機酸化物微粒子が安定に製造出来ない傾向になる。一方メルカプト基含有シランカップリング剤の重量比率が１０を越えても、エポキシ基を含有する重合体に対する結合部位の割合はすでに十分であり、これ以上のメルカプト基量含有シランカップリング剤を使用しても実用的でない。
【００５４】
次に前記第１の工程で製造されたメルカプト基を有する無機酸化物微粒子の存在下で、エポキシ基と１個のラジカル重合性基とを有する単量体の少なくとも１種をラジカル共重合する（第１−２の工程）。
メルカプト基を有する無機酸化物微粒子の存在下で、単量体のラジカル重合を行うことにより、重合過程で、成長反応の単量体のラジカルと、無機酸化物微粒子に結合したメルカプト基との連鎖移動反応が起こり、スルフィド結合を介して、重合体と無機酸化物微粒子が結合する。なお、この際、単量体中のエポキシ基はそのまま維持される。
第２の工程で使用されるエポキシ基と１個のラジカル重合性基を有する単量体（以下「エポキシ基を有する単量体」と言うことがある）としては、グリシジル（メタ）アクリレート、３，４−エポキシシクロヘキシル（メタ）アクリレート等を挙げることができる。
必要であれば前記エポキシ基を有する単量体を、他の単量体と共にラジカル共重合することができる。他の単量体はエポキシ基と反応しないものであれば、特に制限されない。
【００５５】
単量体（エポキシ基を有する単量体及び所望により併用される他の単量体）と無機成分（無機微粒子の固形分）とは、重量比３０／７０〜９５／５で重合反応させるのが好ましく、５０／５０〜９０／１０で重合反応させるのがより好ましい。無機成分の重量比率が７０を越えると安定な無機酸化物微粒子が得られないし、５未満であると、耐摩耗性が不十分になる傾向がある。
【００５６】
このラジカル重合反応は、溶剤中で通常のラジカル重合開始剤を用いて行われる。
溶剤としては、成分（Ａ）の共重合時に使用する有機溶媒はいずれも使用可能であり、また重合開始剤についても同様である。
【００５７】
次に、第２の工程で合成した重合体に、カルボキシル基と（メタ）アクリロイル基を有する化合物を付加させる（第１−３の工程）。
第３の工程に用いられるカルボキシル基と（メタ）アクリロイル基を有する化合物（以下、「（メタ）アクリロイル基導入試薬」という）としては、例えば、（メタ）アクリル酸、２−（メタ）アクリロイルオキシエチルコハク酸、２−（メタ）アクリロイルオキシエチルヘキサヒドロフタル酸、ペンタエリスリトールトリ（メタ）アクリレートと無水コハク酸、無水フタル酸、ヘキサヒドロ無水フタル酸等の酸無水物の付加体、ジペンタエリスリトールペンタ（メタ）アクリレートと無水コハク酸、無水フタル酸、ヘキサヒドロ無水フタル酸等の酸無水物の付加体等を挙げることができる。前記第３の工程では、重合体が有するエポキシ基と、（メタ）アクリロイル基導入試薬が有するカルボキシル基が反応する。重合体と（メタ）アクリロイル基導入試薬とは、エポキシ基／カルボキシル基が１以上となる割合で混合するのが好ましく、１〜１０になる割合でするのがより好ましい。
【００５８】
反応は、５０〜１１０℃で３〜５０時間行うのが好ましい。本反応では、反応を促進させるために、例えば、トリエチルアミン、トリブチルアミン、トリエチレンジアミン、Ｎ，Ｎ−ジメチルベンジルアミン、ベンジルトリメチルアンモニウムクロリド、トリフェニルホスフィン等の公知の触媒を使用することができる。その使用量は反応混合物に対して０．０１〜２重量％であるのが好ましく、０．０５〜１重量％であるのがより好ましい。
【００５９】
また、本反応では（メタ）アクリロイル基によるラジカル重合を防止するために、例えば、ハイドロキノン、ハイドロキノンモノメチルエーテル、カテコール、ｐ−ｔ−ブチルカテコール、フェノチアジン等の重合禁止剤を使用するのが好ましい。重合禁止剤の使用量は、反応混合物に対して０．０１〜１重量％であるのが好ましく、０．０５〜５重量％であるのがより好ましい。
また、塗工性を向上する目的で溶剤をさらに添加することが望ましい場合がある。
【００６０】
用いられる溶剤は、前記無機酸化物微粒子の各製造工程に用いられる種々の反応溶媒であっても良く、例えば、前記第１工程で使用される無機酸化物微粒子の分散媒であっても、また前記第２の工程の反応に用いられる溶媒であっても良い。さらに、前記無機酸化物微粒子を製造した後に、粘度調整のため用いられる溶剤であっても良い。
【００６１】
（Ｄ）の側鎖が、前記（３）式で示されるシリルエーテル基である、重合性官能基を有するポリマーが結合した無機酸化物微粒子を製造する他の方法として、以下に示す方法（第２の方法）が生成物の純度等が高く、好ましい場合がある。
【００６２】
（第２の方法）
メルカプト基を有するアルコキシシランの存在下で、エポキシ基と１個のラジカル重合性基とを有する単量体の少なくとも１種をラジカル共重合する（第２−１の工程）。
メルカプト基を有するアルコキシシランの存在下で、単量体のラジカル重合を行うことにより、重合過程で、成長反応の単量体のラジカルと、メルカプト基との連鎖移動反応が起こり、スルフィド結合を介して、重合体末端にアルコキシシリル基が導入される。なお、この際、単量体中のエポキシ基はそのまま維持される。
第１の工程で使用されるエポキシ基と１個のラジカル重合性基を有する単量体（以下「エポキシ基を有する単量体」と言うことがある）としては、グリシジル（メタ）アクリレート、３，４−エポキシシクロヘキシル（メタ）アクリレート等を挙げることができる。
必要であれば前記エポキシ基を有する単量体を、他の単量体と共にラジカル共重合することができる。このような他の単量体は、ラジカル重合性であれば、特に制限されない。
メルカプト基含有アルコキシシランは、１分子中にメルカプト基とアルコキシシリル基を有するものであれば、成分（Ａ）についての説明と同様であり、特にその構造は制限されない。
【００６３】
前記エポキシ基を有する単量体とともに、他の単量体を併用する場合は、前記エポキシ基を有する単量体と他の単量体とは、重量比が１００／０〜１０／９０の割合で用いられるのが好ましく、１００／０〜３０／７０の割合で用いられるのがより好ましい。前記エポキシ基を有する単量体の割合が１０重量％未満であると、後述する第３の工程において導入される（メタ）アクリロイル基の導入量が少なくなり、十分な耐摩耗性が得られない場合がある。
【００６４】
このラジカル重合反応は、溶剤中で通常のラジカル重合開始剤を用いて行われる。
単量体とメルカプト基を有するアルコキシシランの重量比は９９．５／０．５〜９０／１０、好ましくは９９／１〜９３／７である。メルカプト基を有するアルコキシシランの重量比が０．５未満では、末端に導入されるアルコキシシリル基の数が少なく、無機酸化物微粒子の表面を修飾するのに十分な官能基が存在しているとは言い難い。一方、１０以上では得られる共重合体の分子量が小さすぎ、物性的に好ましくない場合がある。重合用の溶剤としては、成分（Ａ）の調製の場合と同様の有機溶媒が用いられる。
【００６５】
重合反応に使用するラジカル重合開始剤も成分（Ａ）の調製の場合と同様である。
【００６６】
次に、第１の工程で合成した重合体に、カルボキシル基と（メタ）アクリロイル基を有する化合物を付加させる（第２−２の工程）。
第２の工程に用いられるカルボキシル基と（メタ）アクリロイル基を有する化合物（以下、「（メタ）アクリロイル基導入試薬」という）としては、例えば、（メタ）アクリル酸、２−（メタ）アクリロイルオキシエチルコハク酸、２−（メタ）アクリロイルオキシエチルヘキサヒドロフタル酸、ペンタエリスリトールトリ（メタ）アクリレートと無水コハク酸、無水フタル酸、ヘキサヒドロ無水フタル酸等の酸無水物の付加体、ジペンタエリスリトールペンタ（メタ）アクリレートと無水コハク酸、無水フタル酸、ヘキサヒドロ無水フタル酸等の酸無水物の付加体等を挙げることができる。前記第２の工程では、重合体が有するエポキシ基と、（メタ）アクリロイル基導入試薬が有するカルボキシル基が反応する。重合体と（メタ）アクリロイル基導入試薬とは、エポキシ基／カルボキシル基が１以上となる割合で混合するのが好ましく、１〜１０になる割合でするのがより好ましい。
【００６７】
反応は、５０〜１１０℃で３〜５０時間行うのが好ましい。本反応では、反応を促進させるために、例えば、トリエチルアミン、トリブチルアミン、トリエチレンジアミン、Ｎ，Ｎ−ジメチルベンジルアミン、ベンジルトリメチルアンモニウムクロリド、トリフェニルホスフィン等の公知の触媒を使用することができる。その使用量は反応混合物に対して０．０１〜２重量％であるのが好ましく、０．０５〜１重量％であるのがより好ましい。
【００６８】
また、本反応では（メタ）アクリロイル基によるラジカル重合を防止するために、例えば、ハイドロキノン、ハイドロキノンモノメチルエーテル、カテコール、ｐ−ｔ−ブチルカテコール、フェノチアジン等の重合禁止剤を使用するのが好ましい。重合禁止剤の使用量は、反応混合物に対して０．０１〜１重量％であるのが好ましく、０．０５〜５重量％であるのがより好ましい。
また、塗工性を向上する目的で溶剤をさらに添加することが望ましい場合がある。
【００６９】
用いられる溶剤は、前記無機酸化物微粒子の各製造工程に用いられる種々の反応溶媒であっても良く、例えば、前記第１工程で使用される溶媒であっても、また前記第２の工程の反応に用いられる溶媒であっても良い。さらに、粘度調整のため用いられる溶剤であっても良い。
【００７０】
次に第２の工程で得られた重合体のアルコキシシリル基を、無機酸化物微粒子を加水分解縮合し、所定の構造を有する無機酸化物微粒子を合成する（第２−３の工程）。
【００７１】
ここで無機酸化物微粒子としては、成分（Ａ）の調製時と同様のものが使用される。
【００７２】
第２−２の工程で得られた重合体と無機酸化物微粒子の反応、結合に際して、水、触媒、有機溶媒等の使用態様、反応様式等は成分（Ａ）の場合と同様である。
【００７３】
反応は２０〜１００℃、１〜１００時間、好ましくは２０〜２５℃で４時間以上反応の後、４０〜７０℃で１〜１０時間加熱し、反応を進行させる。また、副反応を抑えるため、溶媒で反応系を希釈しても良い。用いられる溶媒としては用いる水、触媒と相性の良いものが好ましく、例えば、メタノール、エタノール、イソプロパノール、イソブタノール、等のアルコール類、アセトン、メチルエチルケトン、メチルイソブチルケトン等のケトン類、テトラヒドロフラン、ジオキサン、等のエーテル類、プロピレングリコールモノメチルエーテル等の水酸基含有エーテル類、等を挙げることができる。
反応系におけるアルコキシシリル基含有ポリマーと無機酸化物微粒子（固形分）との重量比は、３０／７０〜９５／５で反応させるのが好ましく、５０／５０〜９０／１０で反応させるのがより好ましい。無機成分の重量比率が７０を越えると安定な無機酸化物微粒子が得られないし、５未満であると、耐摩耗性が不十分になる傾向がある。
【００７４】
本発明の組成物は、そのまま耐汚染性付与剤として使用できるが、必要に応じ塗膜物性を改良する目的で、例えば、紫外線吸収剤（例えばベンゾトリアゾール系、ベンゾフェノン系、サリチル酸系、シアノアクリレート系紫外線吸収剤）、酸化防止剤（例えばヒンダードフェノール系、硫黄系、リン系酸化防止剤）、光安定剤（例えばヒンダードアミン系光安定剤）、ブロッキング防止剤、スリップ剤、レベリング剤などの、この種の組成物中に配合される種々の添加剤を皮膜に形成する組成中に、それぞれ０．０１〜２重量％配合することができる。
さらに、耐汚染性付与剤（被覆組成物）の粘度調整のため重合体の製造の際に用いた有機溶剤と同一のものを使用することができる。加えて、必要に応じ、他の重合体、ラジカル重合性モノマー、オリゴマー等を本発明で実現しうるような塗膜の物性を損なわない範囲で添加することができる。
【００７５】
本発明にかかる耐汚染性付与剤は、例えば、ポリエチレンテレフタレート、ポリエチレンナフタレート等のポリエステル、ＰＭＭＡ、またはＭＭＡ共重合体（例えばＭＳ樹脂）、ポリカーボネート、トリアセチルセルロース、ＡＢＳ樹脂等のプラスチック基材に、デイップコート、フローコート、スピンコート、スプレーコート、バーコート、グラビアコート、ロールコート、ブレードコート、エアナイフコート等の塗工方法で、溶剤乾燥により塗膜を形成後、活性エネルギー線照射することにより、プラスチック基材表面に１〜５０μｍ、好ましくは２〜２０μｍのコート層が得られる条件の下、塗工される。
【００７６】
活性エネルギー線照射法としては、キセノンランプ、低圧水銀灯、高圧水銀灯、超高圧水銀灯、メタルハライドランプ、カーボンアーク灯、タングステンランプ等の光源から発せられる紫外線、または通常２０〜２０００ｋＶの粒子加速器から取り出される電子線、α線、β線、γ線、等の活性エネルギー線を照射し、硬化させて被膜を形成させる。このような活性エネルギー線で硬化した被膜は生産性・物性のバランスに優れ、特に好ましい。
【００７７】
本発明にかかる耐汚染性付与剤を用い、以上のような方法で作成した塗膜は以下のような物性を有する。
１）鉛筆硬度
耐汚染性付与剤を、１００μｍ厚のＰＥＴフィルムに乾燥膜厚５μｍで塗布し、硬化させた後の塗膜の鉛筆硬度は５Ｂ以上である。更に耐汚染性付与剤が活性エネルギー線硬化性の成分を含む場合には、その鉛筆硬度は２Ｈ以上、より好ましくは３Ｈ以上である。
２）水に対する接触角
耐汚染性付与剤を塗布、硬化して得られる塗膜の、水に対する接触角は８０度以上、好ましく８５度以上である。８０度未満の場合、撥水性が低いため、特に指紋や皮脂のふき取り性が低下し、好ましくない。
【００７８】
３）オレイン酸、トリオレイン（オレイン酸トリグリセリド）、スクアレン（非環式トリテルペンの１つ。イソプレン残基６個からなる鎖状構造の炭化水素。Ｃ_３０Ｈ_５０）に対する接触角
耐汚染性付与剤を塗布、硬化して得られる塗膜の、上記物質に対する接触角はすべて１０度以下である。５度以下であれば、さらに好ましい。１０度を越える場合、親油性が低いため、特に指紋や皮脂の付着時、非常に目立ち易い。即ち、ヘイズが大幅に悪化し、光沢度も低下する。
このようにして得られた塗膜に指紋を付着させた場合、ほとんど付着しないか、付着しても１回でテイッシュやハンカチ等で容易にふき取れる。また、通常の塗膜や従来の撥水・撥油設計の塗膜で特に問題になっていた皮脂汚れ（特に顔脂や鼻脂の汚れ）に関して、撥水・撥油設計の塗膜では付着時のヘイズ変化が１０〜２０と大きかったのに対し、本発明の塗膜では２〜５と小さく、付着させても目立ちにくい。一方、ふき取り性に関しては、撥水・撥油設計の塗膜では８回以上と多くの回数を要したのに対し、本発明の塗膜では４回以下と少ない回数で完全にふき取れるようになった（１回〜２回のふき取りで実質的にはほとんど汚れが目立たなくなる）。また、基材の透明性も損なわず、耐傷つき性やカール性にも非常にすぐれた塗膜を得ることも可能である。
【００７９】
以下、実施例と比較例、参考例により、本発明を更に詳細に説明するが、本発明はこれら実施例により、限定されるものではない。なお、例中の部および％は、それぞれ重量部および重量％を意味する。
実施例等における塗膜の評価方法を以下に示した。
（１）透明性
ヘイズ値で評価した（ＪＩＳ Ｋ−７１０５）。
（２）耐摩耗性
摩耗輪（Ｃａｌｉｂｒａｓｅ社製：ＣＳ−１０Ｆ）を用い、荷重５００ｇで１００回転テーバー摩耗試験を行い、テーバー摩耗試験後のヘイズ値と試験前のヘイズ値の差△Ｈ（％）で評価した。
（３）鉛筆硬度
ＪＩＳ準拠鉛筆硬度計系（太佑機材株式会社製）を用い、ＪＩＳ Ｋ−５４００の条件に基づき、測定を行い、傷の入らないもっとも硬い鉛筆の番手で示した。
（４）カール性
塗膜を１０ｃｍ角に塗布し、静置時の４角の浮き上がり量の平均値（ｍｍ）で評価した。
（５）塗膜密着性
ＪＩＳ Ｋ５４００ 記載の碁盤目法（１ｍｍ間隔で１００個の碁盤目を入れ、セロハンテープ（ニチバン株式会社製、商品名）で試験した。但し評価方法を同じ操作を５回繰り返し（セロハンテープは常に新しいものを用いる）、全く傷やはがれの生じないものを○、１０％以下の傷やはがれを生じるものを△、それ以外を×、とする方法に変更し、測定評価した。
（６）水に対する接触角
塗膜に０．００２ｍｌの純水を滴下し、１分後の接触角を測定した。なお、接触角の測定には、Ｐ型接触角測定器（協和科学株式会社製）を用いた（単位；度）。
（７）オレイン酸、トリオレイン及びスクアレンに対する接触角
純水の代わりに、これらの溶剤を使用する以外は、（６）に記載の方法で、接触角を測定した（単位；度）。
（８）耐指紋汚れ性
付着性：掌で握り、少し湿らせた親指を塗膜に垂直に３秒間押しつけ、塗膜に指紋を付ける。
付着性は指紋付着後のヘイズで評価した。
ふき取り性：市販のテイッシュで表面を軽くふき、目視で指紋汚れが見えなくなるまでの回数で評価した。
（９）耐皮脂汚れ性
付着性：鼻脂を親指につけ、その親指を塗膜に垂直に３秒間押しつけ、塗膜に指紋を付ける。
付着性は鼻脂付着後のヘイズで評価した。
ふき取り性：市販のテイッシュで表面を軽くふき、目視で皮脂汚れが見えなくなるまでの回数で評価した。
【００８０】
［参考例１］ （耐汚染性付与剤１の合成）
メチルメタクリレート４０ｇ、ステアリルメタクリレート２０ｇ、メチルエチルケトン（ＭＥＫ）２００ｇを攪拌混合し、重合開始剤（２，２’−アゾビス（２，４−ジメチルバレロニトリル）、和光純薬工業株式会社製、Ｖ−６５）を０．５ｇ添加し、６５℃に窒素気流下昇温し、その温度で５時間維持した（途中Ｖ−６５を０．５ｇ追加添加）。その後内温を７５〜８０℃に上げ、２時間維持し、残存するＶ−６５を完全に分解させた。その後室温に冷却し、固形分２４％、数平均分子量１８０００のポリマーが得られた（耐汚染性付与剤１＝ＡＦ１）。
【００８１】
［参考例２］ （耐汚染性付与剤２の合成）
メチルメタクリレート３０ｇ、ステアリルメタクリレート２０ｇ、ポリエチレングリコールモノアクリレート１０ｇ（ブレンマーＡＥ４００；日本油脂株式会社製）、ＭＥＫ２００ｇを攪拌混合し、Ｖ−６５を０．５ｇ添加し、６５℃に窒素気流下昇温し、その温度で５時間維持した（途中Ｖ−６５を０．５ｇ追加添加）。その後内温を７５〜８０℃に上げ、２時間維持し、残存するＶ−６５を完全に分解させた。その後室温に冷却し、固形分２４％、数平均分子量１７０００のポリマーが得られた（耐汚染性付与剤２＝ＡＦ２）。
【００８２】
［参考例３］ （耐汚染性付与剤３の合成）
メルカプトプロピルトリメトキシシラン（信越化学工業株式会社製、ＫＢＭ８０３）を２ｇと固形分３０％のＭＥＫ分散オルガノシリカゾル（日産化学工業株式会社製、ＭＥＫ−ＳＴ）７０ｇとから出発して得られたＳＨ基含有シリカゾル、メチルメタクリレート３０ｇ、ステアリルメタクリレート２０ｇ、ポリエチレングリコールモノアクリレート１０ｇ（ブレンマーＡＥ４００；日本油脂株式会社製）、ＭＥＫ２００ｇを攪拌混合し、Ｖ−６５を０．５ｇ添加し、６５℃に窒素気流下昇温し、その温度で５時間維持した（途中Ｖ−６５を０．５ｇ追加添加）。その後内温を７５〜８０℃に上げ、２時間維持し、残存するＶ−６５を完全に分解させた。その後室温に冷却し、固形分２６％のシリカ含有ポリマーが得られた（耐汚染性付与剤３＝ＡＦ３）。
【００８３】
［参考例４］ （耐汚染性付与剤４の合成）
ＫＢＭ８０３を２ｇと固形分２０％のイソプロパノール分散オルガノシリカゾル（日産化学工業株式会社製、ＩＰＡ−ＳＴＵＰ）１００ｇとから出発して得られたＳＨ基含有シリカゾル、メチルメタクリレート３０ｇ、ステアリルメタクリレート２０ｇ、ポリエチレングリコールモノアクリレート１０ｇ（ブレンマーＡＥ４００；日本油脂株式会社製）、ＩＰＡ２００ｇを攪拌混合し、Ｖ−６５を０．５ｇ添加し、６５℃に窒素気流下昇温し、その温度で５時間維持した（途中Ｖ−６５を０．５ｇ追加添加）。その後内温を７５〜８０℃に上げ、２時間維持し、残存するＶ−６５を完全に分解させた。その後室温に冷却し、固形分２５％のシリカ含有ポリマーが得られた（耐汚染性付与剤４＝ＡＦ４）。
【００８４】
［参考例５］ （耐汚染性付与剤５の合成）
メチルメタクリレート４０ｇ、ステアリルメタクリレート１５ｇ、トリシクロデセンモノメタノールメタクリレート５ｇ、アクリル酸２ｇ、ＭＥＫ２００ｇを攪拌混合し、Ｖ−６５を０．５ｇ添加し、６５℃に窒素気流下昇温し、その温度で５時間維持した（途中Ｖ−６５を０．５ｇ追加添加）。その後内温を７５〜８０℃に上げ、２時間維持し、残存するＶ−６５を完全に分解させた。その後室温に冷却し、固形分２５％、数平均分子量１９０００のポリマーが得られた（耐汚染性付与剤５＝ＡＦ５）。
【００８５】
［参考例６］ （ＯＨ基含有多官能アクリレートとＮＣＯ基含有シランカップリング剤の反応による多官能アクリロイル基を有するシランカップリング剤の合成）
ジペンタエリスリトールペンタアクリレートとジペンタエリスリトールヘキサアクリレートの混合物（日本化薬株式会社製、カヤラッドＤＰＨＡ）１ｋｇとγ−トリエトキシシリルプロピルイソシアネート（信越化学工業株式会社製、ＫＢＥ９００７）５０ｇ、ジブチルスズジラウレート０．２ｇ、ハイドロキノンモノメチルエーテル０．５ｇを攪拌混合の後、空気気流下９０℃に昇温し、その温度で１時間維持した。ＩＲでＮＣＯ基に対応する吸収が完全に消失していることを確認し、その後室温に戻し、生成物を取り出した。反応は定量的であった。（シランカップリング剤１＝ＳＣ１）
【００８６】
［参考例７］ （コロイダルシリカと、多官能アクリロイル基を有するシランカップリング剤との反応）
ＭＥＫ分散オルガノシリカゾル（日産化学工業株式会社製、ＭＥＫ−ＳＴ、固形分３０％）４００ｇ、シランカップリング剤１（多官能アクリロイル基含有シランカップリング剤と、未反応多官能アクリレートの混合物）４００ｇ、ヒドロキノンモノメチルエーテル０．４ｇ、アセチルアセトンアルミニウム４ｇ、をよく攪拌混合の後、純水８ｇを加え、室温で３時間以上攪拌を続けた。その後、空気雰囲気下、５０〜７０℃に昇温し、その温度で２時間以上攪拌継続し、シリカゾルの表面にシランカップリング剤を反応させ保護コロイド化を行った（処理コロイダルシリカ１＝ＳＩ１）。
【００８７】
［参考例８］ （シラン末端ポリマーの合成とコロイダルシリカとの反応）
グリシジルメタクリレート９５ｇ、メルカプトプロピルトリメトキシシラン（信越化学工業株式会社製、ＫＢＭ８０３）３ｇ、プロピレングリコールモノメチルエーテルアセテート（ＰＧＭＡｃ）２００ｇを混合した後、内温を窒素気流化約６０℃まで昇温した。その後Ｖ−６５を２回に分け、合計１．５ｇ添加し、６５℃で６時間攪拌を続けた。その後、内温を１００℃まで上げ、Ｖ−６５を完全に失活させた後、ＰＧＭＡｃ２００ｇ、トリフェニルホスフィン１．５ｇを加え、均一になるまで空気雰囲気下で攪拌を続けた。その後、アクリル酸４９ｇ／ＰＧＭＡｃ１０ｇの混合物を約２０分かけて添加し、その後１１０℃にまで内温を上げ、８時間以上維持・攪拌し、アクリル酸とエポキシ基の反応を完結させた。内容混合物を室温に戻した後、ＭＥＫ−ＳＴ１６３ｇ、アルミニウムアセチルアセトナート０．０４ｇを加え、均一になるまで攪拌の後、純水０．９９ｇを加え、室温で３時間、５０〜７０℃で約４時間反応を行った。その後、内温を室温に戻した。固形分濃度は約３０％であった（処理コロイダルシリカ２＝ＳＩ２）。
【００８８】
［参考例９］ （特開２００１−３５３８０８号公報記載のシランカップリング剤の調製）
２−トリクロロシランエチルステアレートをメタノールで分解し、２−トリメトキシシリルエチルステアレートを得た（シランカップリング剤２＝ＳＣ２）。
【００８９】
［参考例１０］ （本発明の範囲外の耐汚染性付与剤の調製）
メチルメタクリレート４０ｇ、ステアリルメタクリレート２０ｇ、パーフルオロオクチルエチルメタクリレート５ｇ、ＭＥＫ２００ｇを攪拌混合し、Ｖ−６５を０．５ｇ添加し、６５℃に窒素気流下昇温し、その温度で５時間維持した（途中Ｖ−６５を０．５ｇ追加添加）。その後内温を７５〜８０℃に上げ、２時間維持し、残存するＶ−６５を完全に分解させた。その後室温に冷却し、固形分２６％、数平均分子量１８０００のポリマーが得られた（耐汚染性付与剤６＝ＡＦ６）。
【００９０】
［参考例１１］ （本発明の範囲外の耐汚染性付与剤の調製）
メチルメタクリレート４０ｇ、ステアリルメタクリレート２０ｇ、ビスメルカプトポリジメチルシロキサン（信越化学工業株式会社製；Ｘ−２２−１６７Ｂ）５ｇ、ＭＥＫ２００ｇを攪拌混合し、Ｖ−６５を０．５ｇ添加し、６５℃に窒素気流下昇温し、その温度で５時間維持した（途中Ｖ−６５を０．５ｇ追加添加）。その後内温を７５〜８０℃に上げ、２時間維持し、残存するＶ−６５を完全に分解させた。その後室温に冷却し、固形分２６％、数平均分子量１７０００のポリマーが得られた（耐汚染性付与剤７＝ＡＦ７）。
【００９１】
［参考例１２］ （本発明の範囲外の耐汚染性付与剤の調製）
メチルメタクリレート４０ｇ、ｎ−デシルメタクリレート２０ｇ、ＭＥＫ２００ｇを攪拌混合し、Ｖ−６５を０．５ｇ添加し、６５℃に窒素気流下昇温し、その温度で５時間維持した（途中Ｖ−６５を０．５ｇ追加添加）。その後内温を７５〜８０℃に上げ、２時間維持し、残存するＶ−６５を完全に分解させた。その後室温に冷却し、固形分２４％、数平均分子量１９０００のポリマーが得られた（耐汚染性付与剤８＝ＡＦ８）。
【００９２】
［実施例１〜１２］及び［比較例１〜７］
表１に示すような配合で、それぞれの組成物を作成した。該組成物を使用して、以下の方法で塗膜を作成し、評価した。塗膜は透明（ヘイズ値１．５％）な１００ミクロン厚のポリエチレンテレフタレートフィルム（三菱化学ポリエステルフィルム株式会社製：Ｔ６００Ｅ）にバーコータを用いて、乾燥後の膜塗厚が６μｍになるように塗布し、８０℃で２分間加熱乾燥して形成した。このものを出力密度１２０Ｗ／ｃｍの高圧水銀灯を用い、その塗膜について透明性、耐摩耗性、鉛筆硬度、塗膜密着性、カール性、接触角（水、スクアレン、オレイン酸、トリオレイン）耐指紋汚れ性・耐皮脂汚れ性を評価した。組成物の配合については表１、評価結果については表２、表３に示す。
結果から明らかなように、本発明の範囲内の物性を示す塗膜は、耐指紋汚れ性・耐皮脂汚れ性に非常に優れているが、本発明の範囲外の物性を示す塗膜は、耐指紋汚れ性・耐皮脂汚れに劣り、特に耐皮脂汚れ性に関しては本発明の範囲内の物性を示す塗膜に比べ、大きく劣ることは明らかであった。
【００９３】
【表１】

ＤＰＨＡ：ジペンタエリスリトールヘキサ／ペンタアクリレート（日本化薬株式会社製）
ＤＰＨＡ＊：ＳＩ１中のＤＰＨＡ
Ｕ１５ＨＡ：多官能ウレタンアクリレート（新中村化学株式会社製）
ＳＩ１／ＳＩ２：配合比（固形分で）２／１
Ｉ１８４：イルガキュア１８４（チバスペシャリテイケミカルズ株式会社製）
注：溶剤はＭＥＫ、ＰＧＭ、ＰＧＭＡｃ、ＩＰＡの混合溶媒を使用
【００９４】
【表２】

【００９５】
【表３】

【００９６】
［比較例８］
ＳＣ２をエタノール／トリアセチルアセトンアルミニウム触媒の存在下、計算量の１．２倍量の水で加水分解し、縮合物を得た。
厚み１００μｍのＰＥＴフィルム（ヘイズ＝１．５％）上に、比較例１に記載の塗膜を厚み６μｍで作成後、上の縮合物を乾燥後の厚みが０．１μｍになるように塗布し、１００℃で５分間処理し、防汚塗膜を表面に設けた。
塗膜の物性は、ヘイズ＝１．６％、耐摩耗性＝５．１％、鉛筆硬度Ｈ、カール性２ｍｍ、密着性△、接触角＝（水）８３度、（スクアレン）１０度、（オレイン酸）７度、（トリオレイン）１０度であり、耐指紋汚れ性は付着時のヘイズ＝３．２％／ふき取り性＝２回、耐皮脂汚れ性は付着時のヘイズ＝６．６％／ふき取り性＝６回であり、初期の耐指紋汚れ性・耐皮脂汚れ性は、本発明の範囲内の塗膜と比較するとやや劣るものの、一般的な防汚・耐指紋汚れ性コート剤の塗膜と比べると良好である。しかし、鉛筆硬度が低く、密着性も劣るため、耐指紋汚れ性・耐皮脂汚れ性を繰り返し評価すると、徐々に細かい傷の生成や塗膜の剥がれが起こり、耐汚れ性は低下するため、実用的には大きな問題があることは明らかであった。
【００９７】
［実施例１３〜１５］及び［比較例９〜１２］
乾燥後の膜厚が約２μｍとなるように、表４に示す成分（Ａ）を単独で使用し塗膜を形成した。塗布基材、塗布方法、乾燥方法等は実施例１と同様に行い塗膜物性を評価した。評価結果を表４に示した。
表４の結果から明らかなように、実施例１３〜１５の成分は、耐指紋汚れ性に優れているので、硬度をあまり必要としない分野（例えば、柔軟性の求められる製品への耐指紋汚れ性付与）では問題なく用いることができる。
【００９８】
【表４】

【００９９】
【発明の効果】
本発明の耐汚染性付与剤によれば、非常に高いレベルの耐指紋汚れ性・耐皮脂汚れ性を有する塗膜の作成を実現することができる。また、組成物に多官能アクリレートや、無機酸化物微粒子の表面に、−Ｏ−Ｓｉ−Ｒ−結合を介して（メタ）アクリロイル基を有する基が結合している無機酸化物微粒子を含有させることで、同時に卓越した硬度、耐傷つき性、透明性、低カール性等を併せ持つことが可能であり、耐タッチパネル、デイスプレイ、携帯電話筐体、光デイスクなど幅広い用途に好適に使用することができる。
即ち、本発明の耐汚染性付与剤を、例えばＰＥＴ、ＴＡＣ、ＰＭＭＡといった代表的な透明基材に塗布した場合、鉛筆硬度が２Ｈ以上と高い硬度を有し、同時に水に対する接触角が８０度以上と撥水性を示すことで、親水性汚れの付着が防止され、一方、代表的な皮脂成分のオレイン酸、トリオレイン、スクアレンに対する接触角が１０度以下と親油性を示すため、皮脂成分が濡れ、付着時目立たない。一方で水に対する接触角が高いため、指紋や皮脂（同時に水分も存在するため、水より比重が軽い油溶成分が表面に浮き、塗膜と直接接するのは最終的には水分になる）成分の過度のなじみが抑えられ、ふき取り性にも優れる。さらに、撥水基と親水基を組み合わせると、その効果がさらに高くなり、ふき取り性が一層向上するため、従来到達し得なかった高いレベルの耐指紋汚れ性・耐皮脂汚れ性を実現することができる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a stain resistance imparting agent having excellent fingerprint stain resistance and sebum stain resistance, and a stain resistant article using the same. Specifically, an active energy ray-curable stain resistance imparting agent that cures by irradiating with an active energy ray, and at the same time, forms a film with excellent hardness, abrasion resistance, low curl, and transparency, and The present invention relates to a stain-resistant article using the same.
[0002]
[Prior art]
Plastic products, for example, polycarbonate, polymethyl methacrylate, polyethylene terephthalate, polybutylene terephthalate, ABS, MS resin, styrene resin such as AS resin, vinyl chloride resin, resin base material such as cellulose acetate such as triacetyl cellulose, Base material for display devices such as containers, instrument panels, packaging materials, various housing materials, optical disk substrates, plastic lenses, liquid crystal displays, plasma displays, etc., because they are particularly excellent in lightness, ease of processing, impact resistance, etc. And so on.
[0003]
However, these plastic products have low surface hardness and are easily damaged, and transparent resins such as polycarbonate and polyethylene terephthalate have the drawback that the original transparency or appearance of the resin is significantly impaired, and wear resistance is poor. It makes it difficult to use plastic products in the fields that need them.
Therefore, there is a need for an active energy ray-curable hard coat material (coating material) that imparts abrasion resistance to the surface of these plastic products. However, a cured layer of a commercially available active energy ray-curable hard coat material has a tendency that fingerprints and sebum easily adhere to the surface and that stains cannot be easily removed, which impairs the appearance and transparency of the product.
[0004]
To solve such problems, many attempts have been made to increase the resistance to such stains by making the surface a low-energy surface, repelling fingerprints and sebum, and making it less likely to adhere. The techniques can be broadly divided into three approaches.
(1) A method of introducing a perfluoroalkyl group to make the surface water and oil repellent (for example, see Patent Document 1).
(2) A method of introducing a water-repellent silicone resin skeleton such as a polydimethylsiloxane group to make the surface water-repellent and oil-repellent (for example, see Patent Document 2).
(3) A method in which fine irregularities are formed on the surface to further increase water and oil repellency, reduce the contact area, and make the surface more difficult to stain (for example, see Patent Document 3).
However, in these conventional methods, in the application of direct contact with the sebum of the face like a mobile phone, or in the application of repeated contact with a finger like a touch panel, it is still easy to adhere, and because of water and oil repellency, There is a problem that the adhered dirt is repelled and the dirt becomes conspicuous.
[0005]
On the other hand, as a technical flow based on an idea slightly different from the above-mentioned method, the following method can be cited.
(4) A method of improving stain resistance by superhydrophilizing the surface (for example, see Patent Document 4).
(5) A method in which a specific hydrophilic group is combined with a water-repellent / oil-repellent group to improve dirt wiping properties (for example, see Patent Documents 5 to 7).
(6) A method in which the surface is made water-repellent and lipophilic to make it more compatible with fingerprints and sebum components, and to make it less noticeable even when attached (see, for example, Patent Document 8).
Among these, the last method is particularly inconspicuous even when adhered, but the surface cannot be sufficiently scratch-resistant, and the wiping property is reduced (particularly, durability such as repeated wiping properties), and multi-step coating is not performed. However, there is a problem such as an increase in cost due to the above, and drastic improvement is required.
[Patent Document 1] JP-A-10-104403
[Patent Document 2] Japanese Patent Application Laid-Open No. 10-7986
[Patent Document 3] JP-A-10-310455
[Patent Document 4] Japanese Patent Application Laid-Open No. 9-268280
[Patent Document 5] JP-A-2000-290535
[Patent Document 6] JP-A-2001-98190
[Patent Document 7] JP-A-2001-98188
[Patent Document 8] JP-A-2001-353808
[0006]
[Problems to be solved by the invention]
The problem to be solved by the present invention is that, compared to these conventional techniques, in particular, while significantly improving the anti-adhesion property of fingerprints and sebum, and the wiping properties, in particular, by irradiating with active energy rays, the composition is cured and has excellent hardness. An object of the present invention is to provide an active energy ray-curable stain resistance imparting agent and a stain resistant article using the same, which can also realize abrasion resistance, transparency and low curl.
[0007]
[Means for Solving the Problems]
The present inventors have previously found that the balance between the water-repellent / oil-repellent groups and the hydrophilic groups is effective in controlling the adhesion / wiping properties of a specific type of stain (eg, a marker for whiteboard). JP 2001-80290 A). At this time, they have found that it is possible to secure the wiping property while blending with the components of the dirt, and have conceived to apply the idea to a design for preventing dirt of fingerprints and sebum components.
Therefore, in order to make ordinary dirt difficult to attach, while ensuring water repellency, it was possible to make fingerprints and sebum component stains less noticeable by conducting various studies. Further, a stain resistance imparting agent having a hydrophilic group at the same time is added to the active energy ray-curable composition, and applied and cured to obtain a coating film having a desired stain-resistant surface with a single-step coating. Was found to be. In addition, since this stain resistance imparting agent (antifouling agent) can exert sufficient performance even with a very small amount of compounding, for example, it has a composition having a hard coat property and a low curl property as an active energy ray-curable composition. Even when blended into the composition, it has excellent stain resistance against fingerprint stains and sebum stains without impairing its performance (for example, excellent abrasion resistance, hardness, transparency, low curl, etc.). It was confirmed that a coating film having the same was obtained, and the present invention was completed.
[0008]
That is, the gist of the present invention is that a coating formed from a stain resistance imparting agent has a pencil hardness of 5B or more, a contact angle to water of 80 ° or more, and a contact angle to oleic acid, triolein and squalene. Is also 10 degrees or less. Further, another gist of the present invention is that a coating film formed from a stain resistance imparting agent has a pencil hardness of 2H or more, a contact angle with water of 80 ° or more, and a contact angle with oleic acid, triolein and squalene. Are all 10 degrees or less. Still another aspect resides in a stain resistant article using these stain resistant agents.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in more detail.
[0010]
(A) (meth) acrylic copolymer containing (meth) acrylate having a water-repellent group containing neither an organo (poly) siloxane group nor an organic fluorine compound group as a copolymer component: (A) component
In the present invention, (1) a water-repellent copolymer component, (2) a high-rigidity copolymer component, and (3) a hydrophilic copolymer component are used as monomers constituting the component (A). Among them, (1) a (meth) acrylate having a water-repellent group containing neither an organo (poly) siloxane group nor an organic fluorine compound group is used as an essential component as the water-repellent copolymer component.
The component (A) may be present in the form of the (meth) acrylic copolymer itself in the stain resistance imparting agent of the present invention. Can be combined in advance. Hereinafter, description will be made in the order of (1) to (4).
[0011]
(1) Examples of the copolymer component having a water-repellent group include (meth) acrylates having an alkyl group or a polycycloalkyl group having 10 or more carbon atoms, preferably 12 or more carbon atoms. Some specific examples include, for example, decyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, behenyl (meth) acrylate, tricyclodecene monomethanol mono (meth) acrylate, and the like. . An alkyl group or a monocycloalkyl group having less than 10 carbon atoms is not preferable because water repellency is not sufficient. The upper limit of the number of carbon atoms is not particularly limited from the viewpoint of water repellency, but is practically selected from a range of about 30. If silicon (mainly polydimethylsiloxane) or fluorine (mainly perfluoroalkyl group), which is generally used as a water-repellent group, is used, oil repellency as well as water repellency occur simultaneously. It is important to use a copolymer component containing no.
(2) High rigidity copolymer component
In the case of the homopolymer of (meth) acrylate obtained by polymerizing only the water-repellent copolymer component (1), problems such as a decrease in hardness are likely to occur. Therefore, styrene, α-methylstyrene, methyl (meth) acrylate, (meth) It is preferable to copolymerize a radical copolymerizable monomer capable of giving a relatively hard polymer such as ethyl acrylate and butyl (meth) acrylate.
(3) Hydrophilic copolymer component
Further, copolymerization of a radical copolymerizable monomer having a hydrophilic group may be preferable because hydrophilicity is appropriately imparted. For example, the following hydrophilization technique can be exemplified.
(I) Introduction of polyalkylene glycol group
(Ii) Introduction of OH group or carboxylic acid group, sulfonic acid group, phosphoric acid group and salts thereof
[0012]
(I) Introduction of polyalkylene glycol group
For the above introduction, copolymerization of a radical polymerizable monomer having a polyalkylene glycol group in a side chain is preferable. Specific examples of such a monomer include polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, and poly (ethylene glycol / propylene glycol) mono (meth) acrylate. These can be obtained, for example, from NOF Corporation under the trade name of Blemmer.
[0013]
(Ii) Introduction of OH group or carboxylic acid group, sulfonic acid group, phosphoric acid group and salts thereof
For the above introduction, copolymerization of a radical polymerizable monomer having these groups is preferable. For example, as a monomer into which an OH group can be introduced, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate and the like can be exemplified.
Examples of the monomer into which a carboxylic acid group can be introduced include acrylic acid, methacrylic acid, methacryloyloxyethyl phthalic acid, and the like. Examples of the monomer into which a sulfonic acid group can be introduced include styrene sulfonic acid. Monomers capable of introducing a phosphate group include mono (meth) acrylate phosphate.
These alkali (earth) metal salts, quaternary ammonium salts, and the like are also effective for imparting hydrophilicity.
[0014]
(4) Component (A) bonded to inorganic oxide fine particles
When it is desired to further impart hardness and hydrophilicity, it is sometimes more preferable to bond the copolymer of the component (A) to the inorganic oxide fine particles.
Although there are several methods for bonding to the inorganic oxide fine particles, the following method is most preferable.
First, mercaptosilane is bound to inorganic oxide fine particles to prepare inorganic oxide fine particles having a mercapto group. When the copolymerizable monomers (1), (2), and (3) constituting the copolymer (A) are radically copolymerized in the presence of such oxide fine particles, the inorganic oxide fine particles having a mercapto group become a polymerization terminator ( (A chain transfer agent), resulting in a form in which the copolymer (A) is bonded to the surface of the inorganic oxide fine particles.
[0015]
The inorganic oxide is not particularly limited, but is preferably an oxide of silicon, aluminum, zirconium, titanium, zinc, lead, germanium, indium, tin, antimony, cerium, lithium or a composite oxide thereof, and specifically, , Silicon oxide (silica), aluminum oxide (alumina), silicon-aluminum composite oxide, zirconium oxide (zirconia), titanium oxide (titania), zinc oxide, tin oxide, antimony-doped oxide Examples thereof include tin, indium-tin composite oxide (ITO), cerium oxide, and silica-lithium oxide composite oxide. Silica or those containing it as a main component are particularly preferred.
The shape of the inorganic oxide fine particles is spherical, hollow, porous, rod-like, fibrous, plate-like or irregular, and among them, spherical is preferable. The primary particle diameter of the metal oxide is preferably from 1 to 100 nm. If the primary particle size is less than 1 nm, the effect of improving mechanical properties is small, while if it is 100 nm or more, secondary aggregation is likely to occur, and transparency and the like are lost, which is not preferable.
These inorganic oxide fine particles can be obtained in a dried powder state or in a state of being dissolved or dispersed in water or an organic solvent. Among them, in order to exhibit excellent dispersibility, it is preferable to use a sol dissolved or dispersed in water or an organic solvent. Typically, an aqueous silica sol dissolved in water, an organic solvent having an OH group, or an organosilica sol dissolved or dispersed in a polar solvent having a ketone group is most preferably used as a main component. As the aqueous silica sol, ST-20 (basic aqueous silica sol, manufactured by Nissan Chemical Industries, Ltd.), ST-O (acidic aqueous silica sol, manufactured by Nissan Chemical Industries, Ltd.), ST-AK (weakly acidic) Aqueous silica / alumina sol, manufactured by Nissan Chemical Industries, Ltd.) and lithium silicate (basic silica / lithium oxide sol, manufactured by Nissan Chemical Industries, Ltd.). Representative examples of the organosilica sol include IPA-ST (isopropanol (IPA) dispersed organosilica sol, manufactured by Nissan Chemical Industries, Ltd.) and MEK-ST (methyl ethyl ketone (MEK) dispersed organosilica sol, manufactured by Nissan Chemical Industries, Ltd.) Or a sol obtained by using these as a raw material and replacing the solvent with an organic solvent having another OH group (for example, a PGM-dispersed organosilica sol or the like).
The solid content in the dispersion is usually 5 to 50% by weight, preferably 10 to 40% by weight, which is easy to handle and easily available.
[0016]
Examples of the mercaptosilane (silane coupling agent having a mercapto group) include, for example, trimethoxysilylpropyl mercaptan (for example, available from Shin-Etsu Chemical Co., Ltd. under the trade name of KBM803, and from Toray Dow Corning Silicone Co., Ltd. under the trade name of SH6062). And the like. In addition, trialkoxysilylalkyl mercaptans such as triethoxysilylpropylmercaptan and trimethoxysilylethylmercaptan, dialkoxyalkylsilylalkylmercaptans such as methyldimethoxysilylpropylmercaptan and methyldiethoxysilylpropylmercaptan may be used.
[0017]
The reaction and bonding can be achieved by various methods generally used in the production of this type of compound. Basically, a method of hydrolyzing an alkoxysilyl group to generate a silanol group, and performing a condensation reaction with an alkoxy group and / or a hydroxyl group on the surface of the inorganic oxide to bond them is common.
Water is used in a range that does not impair the performance of the coating film and the stability of the coating solution, and the amount is usually 1 to 400 mol%, preferably 30 to 200 mol%, based on the alkoxysilyl group. If the amount is less than 1 mol%, hydrolysis and condensation reaction hardly occur, and if it is more than 400 mol%, gelation or the like is apt to occur, which is not preferable. The water used includes distilled water, ion-exchanged water, industrial water, and soft water.
[0018]
Further, in order to accelerate the hydrolysis and condensation reactions, it is also possible to add an acid or an alkali, or another appropriate compound as a catalyst. Various types of these can be used as long as they do not impair the performance of the coating film and the performance of the coating liquid. For example, acid catalysts include hydrogen chloride solution, phosphoric acid solution, inorganic acids such as boric acid, organic acids such as citric acid, maleic acid, acetic acid, and paratoluenesulfonic acid, and alkali catalysts include alcoholic potassium hydroxide, ammonia, and trialkylamines. And heterocyclic-containing amines such as dimethylaminopyridine. In addition, a metal acetylacetone complex such as aluminum triacetylacetonate is also effective.
The amount is 0.1 to 5 parts by weight, preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the mercapto group-containing silane coupling agent.
[0019]
The weight ratio of the inorganic oxide fine particles to the mercaptosilane is from 100 / 0.1 to 100/10, preferably from 100/1 to 100/5. When this ratio is larger than 100 / 0.1, the content of the mercapto group introduced into the inorganic oxide fine particles is low, and as a result, the proportion of the inorganic oxide fine particles having substantially no mercapto group introduced therein increases, Not preferred. On the other hand, if it is smaller than 100/10, the content of the mercapto group contained in the inorganic oxide fine particles is too high, and the molecular weight of the copolymer may be significantly reduced, or conversely, insolubilization may occur due to crosslinking and gelation, Not preferred.
[0020]
In preparing the (meth) acrylic copolymer (A) of the component (A), the above-mentioned (1) water-repellent copolymer component, (2) high-rigidity copolymer component, and (3) hydrophilic copolymer component And (4) the inorganic oxide fine particles, (1) the water-repellent copolymer component is 5 to 60% by weight, preferably 10 to 50% by weight, and (2) the high-rigidity copolymer component is 5 to 80% by weight, preferably 10 to 70% by weight, (3) the hydrophilic copolymer component is 0 to 40% by weight, preferably 0 to 25% by weight, and (4) the inorganic oxide fine particles are 0 to 40% by weight, preferably, in terms of solid matter. It is used in the range of 0 to 30% by weight.
[0021]
In the copolymerization, it is generally preferable to use a solvent in order to improve the uniformity. Examples of such a solvent include alcohol solvents such as methanol, ethanol, isopropanol (IPA) and isobutanol; ketone solvents such as acetone, methyl ethyl ketone (MEK) and methyl isobutyl ketone (MIBK); tetrahydrofuran, dioxane, methoxyethanol, and ethylene glycol monoester. Ether solvents such as ethyl ether, ethylene glycol dimethyl ether and propylene glycol monomethyl ether; carboxylic acid ester solvents such as methyl acetate, ethyl acetate, propyl acetate, butyl propionate and butyl butyrate; propylene glycol monomethyl ether acetate (PGMAc); -Ether ester solvents such as ethoxyethyl acetate, aromatic hydrocarbon solvents such as benzene, toluene and xylene, dimethylform Bromide, organic solvents such as dimethylacetamide is used. Further, water may be added within a range where the uniformity of the reaction system is not impaired.
[0022]
The method of mixing and dissolving the copolymerization component and the solvent is not particularly limited, but it is important to add a radical polymerization initiator within a certain period of time, preferably within three hours after mixing, to start polymerization. After mixing, if left without a radical polymerization initiator, the Michael addition reaction of a mercapto group to a radical polymerizable functional group (double bond) proceeds as a side reaction, especially when the component (4) is contained. When the polymerization is started after 3 hours or more, the physical properties of the copolymer greatly change, which may be undesirable.
[0023]
As the radical polymerization initiator, a known initiator generally used for radical polymerization can be used. Representative examples include organic peroxides such as benzoyl peroxide, di-t-butyl peroxide, cumene hydroperoxide, 2,2′-azobisbutyronitrile, and 2,2′-azobis (2,4 -Azo compounds such as -dimethylvaleronitrile) (V65) and 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile) are particularly preferably used. The total concentration of the monomers (including the component D) in the polymerization liquid is usually 10 to 60% by weight, and the polymerization initiator is usually 0.1 to 10% by weight, preferably 0.1 to 10% by weight, based on the monomer mixture. It is used in an amount of 2 to 2% by weight.
[0024]
The preferred polymerization temperature varies depending on the radical polymerization initiator used, but the polymerization temperature is 20 to 150 ° C and the polymerization time is 1 to 72 hours.
[0025]
When radical polymerization is carried out by allowing mercaptosilane to coexist with a mixture of copolymerized monomers constituting the (meth) acrylic copolymer (A), the mercaptosilane acts as a chain transfer agent, and a copolymer having a silane group at the terminal is obtained. A combination (A) is obtained. The silane-terminated copolymer (A) may be bonded to inorganic oxide fine particles. In such a case, the same method as described above can be employed for the copolymerization method and the method of bonding to the inorganic oxide fine particles.
[0026]
In order to make the stain resistance imparting agent of the present invention curable with an active energy ray, (B) a polyfunctional (meth) acrylate compound is used.
[0027]
The polyfunctional (meth) acrylate compound is not particularly limited as long as it is a compound having three or more (meth) acryloyl groups in one molecule. Typical examples thereof include pentaerythritol tri (meth) acrylate, pentaerythritol tetra Examples include (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ditrimethylolpropanetetra (meth) acrylate, polyester (meth) acrylates, and polyfunctional urethane (meth) acrylates. can do.
[0028]
In the stain resistance imparting agent curable by an active energy ray, (C) a photopolymerization initiator is blended in order to accelerate the curing of the (B) polyfunctional (meth) acrylate compound.
[0029]
Examples of such a photopolymerization initiator include benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, diethoxyacetophenone, benzyldimethyl ketal, 2-hydroxy-2-methylpropiophenone, 1-hydroxycyclohexylphenyl ketone, Benzophenone, 2,4,6-trimethylbenzoindiphenylphosphine oxide, 2-methyl- [4- (methylthio) phenyl] -2-morpholino-1-propanone, 2-benzyl-2-dimethylamino-1- (4-morpho (Linophenyl) -butan-1-one, Michler's ketone, isoamyl N, N-dimethylaminobenzoate, 2-chlorothioxanthone, 2,4-diethylthioxanthone and the like. The initiator may be appropriately used in combination of two or more thereof.
The photopolymerization initiator (C) is used in an amount of 10% by weight or less, preferably 1 to 5% by weight, of the sum of the polymerizable components (A), (B) and (D).
[0030]
(D) Inorganic oxide fine particles having a (meth) acryloyl group bonded to the surface of the inorganic oxide fine particles via a -O-Si-R- bond
In addition, as the inorganic oxide fine particles here, those similar to the inorganic oxide fine particles bonded to the component (A) described above can be used.
[0031]
(D-1) Silane coupling agent having (meth) acryloyl group
In order to bond a group having a (meth) acryloyl group to the surface of the inorganic oxide fine particles via a -O-Si-R- bond, a silane coupling agent having a (meth) acryloyl group is usually used. One such compound is a silane coupling agent having a molecular weight of 300 or more and containing at least one (meth) acryloyl group as a radically polymerizable functional group. The number is not particularly limited, but preferably has 1 to 5 polymerizable functional groups per molecule. The position is not particularly limited, but is preferably at the end of the molecule.
The compound is preferably an organic compound having a functional group represented by the formula (1) at the same time.

(Wherein X and Y are each independently an oxygen atom, a sulfur atom or an imino group).
[0032]
The functional group represented by the formula (1) has an effect of generating excessive cohesive force due to hydrogen bonding between molecules, imparting mechanical strength, adhesion to a substrate, heat resistance, and the like, and has an inorganic oxide surface. Also acts as a spacer between the and the radical polymerizable functional group. Specifically, functional groups of the following formula (2) can be exemplified.
-OCONH-, -SCONH-, -SCSNH-, -OCSNH-, -NHCONH-, -NHCSNH- (2)
Among these groups, -OCONH- and -SCONH- are particularly preferable from the viewpoint of thermal stability and ease of synthesis.
This compound may be an organic compound having a thioether group at the same time. The thioether group also seems to act as a spacer between the silica surface and the radical polymerizable functional group or a specific polar functional group, and has an effect of suppressing excessive aggregation.
[0033]
As the functional group of the silane coupling agent capable of binding to the inorganic oxide, an alkoxysilyl group, which is a group capable of forming a silanol group, is particularly preferable. Examples of the alkoxysilyl group include a monoalkoxysilyl group, a dialkoxysilyl group, and a trialkoxysilyl group, and among them, a trialkoxysilyl group of a lower alcohol such as a trimethoxysilyl group or a triethoxysilyl group has reactivity. It is particularly preferable when considered. The position of these groups in the molecule is preferably at the molecular end opposite to the polymerizable unsaturated group. Further, the number of groups in one molecule is preferably 1 to 3, particularly preferably 1.
[0034]
The silanol group or the silanol group-forming unit is a unit that bonds to the inorganic oxide fine particles by a condensation reaction or a condensation reaction that occurs after hydrolysis. Some preferred examples of such a compound (D-1) are as follows:
(1) a compound in which a (meth) acrylate compound having an OH group and a trialkoxysilane having an NCO group are connected by an -OCONH- bond;
{Circle around (2)} The trialkoxysilane compound having an SH group and one of the NCO groups of the diisocyanate are connected by an -NHCOS- bond, the remaining NCO group is acted on by a (meth) acrylate compound having an OH group, and the -NCOO- bond is used. Connected compounds,
(3) a compound in which a (meth) acrylate compound having an NCO group and a trialkoxysilane having an SH group are connected via an -NHCOS- bond,
{Circle around (4)} A compound containing two or more (meth) acryloyl groups in the molecule and a trialkoxysilane having an SH group form a thioether bond formed by a Michael addition reaction of the SH group to the (meth) acryloyl group. Connected compounds,
(5) a compound obtained by reacting a mono (meth) acrylate of α, ω-hydroxy-terminated polyalkylene glycol with a silane coupling agent having an NCO group;
And the like, but are not limited thereto.
[0035]
Examples of the (meth) acrylate having an OH group include mono (meth) acrylate (for example, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, etc.), di (meth) acrylate (for example, glycerin di (meth) acrylate). A) acrylate, trimethylolpropane di (meth) acrylate, etc.), and tri-poly (meth) acrylates (eg, pentaerythritol triacrylate, dipentaerythritol tri-pentaacrylate, ditrimethylolpropane triacrylate, etc.). .
[0036]
Examples of the trialkoxysilane compound having an NCO group include triethoxysilylpropyl isocyanate (for example, available under the trade name of KBE9007 from Shin-Etsu Chemical Co., Ltd.), trimethoxysilylpropyl isocyanate, or trimethoxysilylpropyl mercaptan (for example, Shin-Etsu Chemical Co., Ltd.) One of trialkoxysilylalkyl mercaptans such as KBM803 (trade name of Toray Dow Corning Silicon Co., Ltd. under the trade name of SH6062) and diisocyanate (for example, isophorone diisocyanate, hexamethylene diisocyanate, MDI, TDI, etc.). Compounds in which an NCO group is connected by a thiourethane bond can be exemplified.
[0037]
A method for producing an —OCONH— bond by a reaction between an OH group and an NCO group is obtained by blending each compound at a ratio of NCO group / OH group ≦ 1, and mixing and stirring at 60 to 100 ° C. for 1 to 20 hours. Can be In this reaction, it is preferable to use a polymerization inhibitor such as, for example, hydroquinone, hydroquinone monomethyl ether, catechol, pt-butylcatechol, and phenothiazine in order to prevent polymerization due to a (meth) acroylyl group during the reaction. The amount is from 0.01 to 1% by weight, preferably from 0.05 to 0.5% by weight, based on the reaction mixture. In order to accelerate the reaction, a known reaction catalyst such as di-n-butyltin dilaurate or diazabicyclooctane (generally abbreviated as DABCO) may be added. Further, this reaction is carried out, for example, ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone, ether solvents such as ethylene glycol diethyl ether and diethylene glycol dimethyl ether, carboxylic acid ester solvents such as ethyl acetate and butyl acetate, and aromatic solvents such as xylene and toluene. The reaction can be carried out in a solvent containing no group capable of reacting with an isocyanate group, such as a hydrocarbon solvent, or simultaneously, in the presence of a polyfunctional acrylate having three or more (meth) acryloyl groups in the molecule.
[0038]
Examples of the (meth) acrylate compound having an NCO group include β-isocyanatoethyl (meth) acrylate (methacrylate is available from Showa Denko KK under the trade name of Karenz MOI) or (meth) acrylates having an OH group. And a compound in which one of NCO groups of diisocyanate (for example, isophorone diisocyanate, hexamethylene diisocyanate, MDI, TDI and the like) is connected by a urethane bond.
[0039]
Examples of the trialkoxysilane compound having an SH group include, for example, trimethoxysilylpropyl mercaptan (available under the trade name of KBM803 from Shin-Etsu Chemical Co., Ltd. and under the trade name of SH6062 from Toray Dow Corning Silicone Co., Ltd.). be able to.
[0040]
The method for forming an -NHCOS- bond by the reaction between the NCO group and the SH group can be performed in the same manner as the method for forming the -NHCOO- bond by the reaction between the NCO group and the OH group.
Examples of the mono (meth) acrylate compound of α, ω-hydroxy-terminated polyalkylene glycol include polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, polytetramethylene glycol mono (meth) acrylate, and poly (ethylene). (Propylene) glycol mono (meth) acrylate, poly (ethylene / tetramethylene) glycol mono (meth) acrylate, and the like.
[0041]
The reaction of a mono (meth) acrylate compound of an α, ω-hydroxy-terminated polyalkylene glycol with a trialkoxysilyl compound having an NCO group is carried out in the same manner as the formation of a -NHCOO- bond by the reaction between an NCO group and an OH group. be able to.
[0042]
The reaction and bonding between (D-1) and the inorganic oxide fine particles can be performed in the same manner as in the case of mercaptosilane and inorganic oxide fine particles described above. The same applies to the use method and amount of water and catalyst.
[0043]
Separately, among components capable of synthesizing (D-1), an alkoxysilyl compound having a functional group capable of generating a bonding group represented by the formula (1) or (2) is first added to the inorganic oxide fine particles. After the reaction, there is a method in which another compound is reacted to introduce a polymerizable unsaturated group and a bonding group represented by the formula (1) or (2). In the formula (1), the trialkoxysilane compound having an SH group as the compound having an alkoxysilyl group can be reacted with the inorganic oxide fine particles in advance.
[0044]
For example, a trialkoxysilane having an SH group is reacted with an inorganic oxide, and then the SH group is reacted with a diisocyanate compound. One of the NCO groups is connected by an -NHCOS- bond, and the other NCO group is connected to an OH group. (Meth) acrylate compound having the formula (1), and connecting by a -NHCOO- bond to obtain a structure similar to that of the above method (3).
[0045]
Further, by reacting a trialkoxysilane having an SH group with an inorganic oxide and then reacting with a (meth) acrylate compound and / or a (meth) acrylamide compound having an NCO group, a structure similar to the above (4) is obtained. Can be obtained.
[0046]
The reaction ratio between the inorganic oxide fine particles and (D-1) is usually 90/10 to 5/95, preferably 80/20 to 10/90 by weight. When inorganic oxide fine particles / (D-1)> 90/10, the surface protection of the inorganic oxide is insufficient, which is not preferable. On the other hand, when inorganic oxide fine particles / (D-1) <5/95. However, it is not preferable because polymerization of the alkoxysilane itself, instability of the dispersion state due to crosslinking, and a significant increase in viscosity are caused. The molecular weight of (D-1) is desirably 300 or more. If it is less than 300, the effect of forming the protective colloid is small, or the silane coupling agent itself is condensed, and aggregation or gelation due to cross-linking or the like is liable to occur.
[0047]
The reaction is carried out at room temperature to 100 ° C. for 1 to 100 hours, preferably at room temperature for 4 hours or more, followed by heating at room temperature to 70 ° C. for 1 to 10 hours to progress the reaction. The reaction system may be diluted with a solvent in order to suppress a side reaction. The solvent used is preferably a silane alkoxide or water which is a hydrolyzate, and those having compatibility with a catalyst, for example, alcohols such as methanol, ethanol, isopropanol and isobutanol, acetone, methyl ethyl ketone, methyl isobutyl ketone and the like. Examples thereof include ketones, ethers such as THF and dioxane, and OH-containing ethers such as propylene glycol monomethyl ether.
[0048]
Further, a part (less than 50% by weight) of (D-1) may be replaced with another silane coupling agent. Other silane coupling agents include, in addition to various known commercially available silane coupling agents, a silane coupling agent having a polyalkylene glycol structure having no radically polymerizable functional group, having a carboxylic acid group or a carboxylic ester group. Examples thereof include a silane coupling agent, a silane coupling agent having an alicyclic structure, and a silane coupling agent obtained by reacting a bulky alcohol having a branched structure with an alkoxysilyl group having an NCO group.
[0049]
Apart from these, inorganic oxide fine particles having a polymer having a polymerizable functional group, in which the side chain of (D) is a silyl ether group represented by the following formula (3), can be used.
-O-Si-RS-Poly (3)
Here, R is an alkylene group having 2 to 10 carbon atoms which may have a branch, and Poly is a polymer unit having at least one (meth) acryloyl group.
The method for producing the inorganic oxide fine particles is not particularly limited, but is preferably produced by the following method.
(First method)
First, a mercapto group-containing silane coupling agent and inorganic oxide fine particles are hydrolyzed and condensed to synthesize inorganic oxide fine particles having a mercapto group (Step 1-1).
[0050]
As the inorganic oxide fine particles, for example, an inorganic material containing inorganic oxide fine particles having a particle diameter of 1 to 100 nm as a solid content of 10 to 40% as a dispersion medium using water and various organic solvents or a mixed solvent thereof. Oxide fine particles are preferred. Specific examples of the organic solvent and the inorganic oxide fine particles are the same as those described above.
[0051]
The hydrolytic condensation reaction between the mercapto group-containing silane coupling agent and the inorganic oxide fine particles is performed by adding water to the mixture. The alkoxysilyl group of the mercapto group-containing silane coupling agent is hydrolyzed with water to generate a silanol group, and a condensation reaction occurs between the silanol and the OH group on the surface of the inorganic oxide fine particles, and has a mercapto group on the surface. Inorganic oxide fine particles are obtained. The amount of water to be added may be an amount at which the alkoxysilyl group of the mercapto group-containing silane coupling agent can be hydrolyzed by 100% as a theoretical amount or more, and is equivalent to 100 to 300%, preferably 100 to 200%. Is added.
[0052]
In order to accelerate this hydrolysis reaction, a hydrolysis catalyst can be added to the reaction system. As the hydrolysis reaction, for example, aluminum acetylacetone, boric acid tributoxide, hydrochloric acid, acetic acid, nitric acid, maleic acid, fumaric acid, oxalic acid, dibutyltin dioctate, p-toluenesulfonic acid, and mixtures thereof are used. Can be. The amount is 0.1 to 5 parts by weight, preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the mercapto group-containing silane coupling agent.
[0053]
The reaction is carried out at 20 to 100 ° C. for 1 to 100 hours, preferably at 20 to 25 ° C. for 4 hours or more, followed by heating at 40 to 70 ° C. for 1 to 10 hours to advance the reaction. Further, the reaction system may be diluted with a solvent in order to suppress a side reaction. The solvent used is preferably water, which has good compatibility with the catalyst.Examples include alcohols such as methanol, ethanol, isopropanol and isobutanol, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, and tetrahydrofuran and dioxane. Examples thereof include ethers and hydroxyl group-containing ethers such as propylene glycol monomethyl ether.
The weight ratio of the mercapto group-containing silane coupling agent to the inorganic oxide fine particles (solid content) in the reaction system is preferably 0.1 / 99.9 to 10/90, and is preferably 1/99 to 5/95. More preferably, there is. When the weight ratio of the mercapto group-containing silane coupling agent is less than 0.1, the amount of mercapto groups bonded to the inorganic oxide fine particles decreases, and the number of sites bonded to the epoxy group-containing polymer decreases. Inorganic oxide microparticles with the coalescence tend to be unable to be produced stably. On the other hand, even if the weight ratio of the mercapto group-containing silane coupling agent exceeds 10, the ratio of the bonding site to the epoxy group-containing polymer is already sufficient, and the use of a mercapto group-containing silane coupling agent with a higher amount is required. It is not practical.
[0054]
Next, in the presence of the inorganic oxide fine particles having a mercapto group produced in the first step, at least one monomer having an epoxy group and one radical polymerizable group is radically copolymerized ( 1-2 step).
By performing radical polymerization of the monomer in the presence of the inorganic oxide fine particles having a mercapto group, a chain of the radical of the monomer of the growth reaction and the mercapto group bonded to the inorganic oxide fine particles during the polymerization process. A transfer reaction occurs, and the polymer and the inorganic oxide fine particles are bonded via a sulfide bond. At this time, the epoxy group in the monomer is maintained as it is.
As a monomer having an epoxy group and one radical polymerizable group (hereinafter sometimes referred to as “monomer having an epoxy group”) used in the second step, glycidyl (meth) acrylate, 3 And 4-epoxycyclohexyl (meth) acrylate.
If necessary, the monomer having an epoxy group can be radically copolymerized with another monomer. Other monomers are not particularly limited as long as they do not react with the epoxy group.
[0055]
The monomer (the monomer having an epoxy group and optionally another monomer used in combination) and the inorganic component (solid content of the inorganic fine particles) are subjected to a polymerization reaction in a weight ratio of 30/70 to 95/5. The polymerization reaction is more preferably performed at 50/50 to 90/10. If the weight ratio of the inorganic component exceeds 70, stable inorganic oxide fine particles cannot be obtained, and if it is less than 5, the abrasion resistance tends to be insufficient.
[0056]
This radical polymerization reaction is carried out in a solvent using a usual radical polymerization initiator.
As the solvent, any organic solvent used at the time of copolymerization of the component (A) can be used, and the same applies to the polymerization initiator.
[0057]
Next, a compound having a carboxyl group and a (meth) acryloyl group is added to the polymer synthesized in the second step (step 1-3).
Examples of the compound having a carboxyl group and a (meth) acryloyl group (hereinafter, referred to as “(meth) acryloyl group-introducing reagent”) used in the third step include (meth) acrylic acid, 2- (meth) acryloyloxy Adducts of ethyl succinic acid, 2- (meth) acryloyloxyethyl hexahydrophthalic acid, pentaerythritol tri (meth) acrylate and acid anhydrides such as succinic anhydride, phthalic anhydride and hexahydrophthalic anhydride; dipentaerythritol pentane Adducts of (meth) acrylate and acid anhydrides such as succinic anhydride, phthalic anhydride and hexahydrophthalic anhydride can be given. In the third step, the epoxy group of the polymer reacts with the carboxyl group of the (meth) acryloyl group introduction reagent. The polymer and the (meth) acryloyl group-introducing reagent are preferably mixed at a ratio where the epoxy group / carboxyl group is 1 or more, more preferably 1 to 10.
[0058]
The reaction is preferably performed at 50 to 110 ° C for 3 to 50 hours. In this reaction, a known catalyst such as triethylamine, tributylamine, triethylenediamine, N, N-dimethylbenzylamine, benzyltrimethylammonium chloride, and triphenylphosphine can be used to promote the reaction. The amount used is preferably from 0.01 to 2% by weight, more preferably from 0.05 to 1% by weight, based on the reaction mixture.
[0059]
In this reaction, it is preferable to use a polymerization inhibitor such as, for example, hydroquinone, hydroquinone monomethyl ether, catechol, pt-butylcatechol, and phenothiazine in order to prevent radical polymerization by (meth) acryloyl group. The use amount of the polymerization inhibitor is preferably from 0.01 to 1% by weight, more preferably from 0.05 to 5% by weight, based on the reaction mixture.
In some cases, it is desirable to further add a solvent for the purpose of improving coatability.
[0060]
The solvent used may be various reaction solvents used in each production step of the inorganic oxide fine particles, for example, a dispersion medium of the inorganic oxide fine particles used in the first step, The solvent used in the reaction of the second step may be used. Further, it may be a solvent used for adjusting the viscosity after producing the inorganic oxide fine particles.
[0061]
As another method for producing inorganic oxide fine particles having a polymer having a polymerizable functional group, wherein the side chain of (D) is a silyl ether group represented by the above formula (3), the following method (No. Method 2) may be preferable because the purity of the product is high.
[0062]
(Second method)
In the presence of an alkoxysilane having a mercapto group, at least one monomer having an epoxy group and one radical polymerizable group is radically copolymerized (Step 2-1).
By performing radical polymerization of the monomer in the presence of an alkoxysilane having a mercapto group, a chain transfer reaction between the radical of the monomer for the growth reaction and the mercapto group occurs in the polymerization process, via a sulfide bond. Thus, an alkoxysilyl group is introduced into the terminal of the polymer. At this time, the epoxy group in the monomer is maintained as it is.
Examples of the monomer having an epoxy group and one radical polymerizable group used in the first step (hereinafter sometimes referred to as “monomer having an epoxy group”) include glycidyl (meth) acrylate, And 4-epoxycyclohexyl (meth) acrylate.
If necessary, the monomer having an epoxy group can be radically copolymerized with another monomer. Such other monomers are not particularly limited as long as they are radically polymerizable.
The mercapto group-containing alkoxysilane is the same as that described for the component (A) as long as it has a mercapto group and an alkoxysilyl group in one molecule, and its structure is not particularly limited.
[0063]
When another monomer is used in combination with the monomer having an epoxy group, the weight ratio of the monomer having the epoxy group and the other monomer is 100/0 to 10/90. It is preferably used in a ratio of 100/0 to 30/70. If the proportion of the monomer having an epoxy group is less than 10% by weight, the amount of the (meth) acryloyl group introduced in the third step described later will be small, and sufficient abrasion resistance cannot be obtained. There are cases.
[0064]
This radical polymerization reaction is carried out in a solvent using a usual radical polymerization initiator.
The weight ratio of the monomer to the alkoxysilane having a mercapto group is 99.5 / 0.5 to 90/10, preferably 99/1 to 93/7. When the weight ratio of the alkoxysilane having a mercapto group is less than 0.5, the number of alkoxysilyl groups introduced into the terminal is small, and sufficient functional groups to modify the surface of the inorganic oxide fine particles are present. Is hard to say. On the other hand, if the molecular weight is 10 or more, the molecular weight of the obtained copolymer is too small, which may be unfavorable in physical properties. As the solvent for polymerization, the same organic solvent as in the case of preparing the component (A) is used.
[0065]
The radical polymerization initiator used in the polymerization reaction is the same as in the case of preparing the component (A).
[0066]
Next, a compound having a carboxyl group and a (meth) acryloyl group is added to the polymer synthesized in the first step (Step 2-2).
Examples of the compound having a carboxyl group and a (meth) acryloyl group (hereinafter referred to as “(meth) acryloyl group-introducing reagent”) used in the second step include, for example, (meth) acrylic acid, 2- (meth) acryloyloxy Adducts of ethyl succinic acid, 2- (meth) acryloyloxyethyl hexahydrophthalic acid, pentaerythritol tri (meth) acrylate and acid anhydrides such as succinic anhydride, phthalic anhydride and hexahydrophthalic anhydride; dipentaerythritol pentane Adducts of (meth) acrylate and acid anhydrides such as succinic anhydride, phthalic anhydride and hexahydrophthalic anhydride can be given. In the second step, the epoxy group of the polymer reacts with the carboxyl group of the (meth) acryloyl group introduction reagent. The polymer and the (meth) acryloyl group-introducing reagent are preferably mixed at a ratio where the epoxy group / carboxyl group is 1 or more, more preferably 1 to 10.
[0067]
The reaction is preferably performed at 50 to 110 ° C for 3 to 50 hours. In this reaction, a known catalyst such as triethylamine, tributylamine, triethylenediamine, N, N-dimethylbenzylamine, benzyltrimethylammonium chloride, and triphenylphosphine can be used to promote the reaction. The amount used is preferably from 0.01 to 2% by weight, more preferably from 0.05 to 1% by weight, based on the reaction mixture.
[0068]
In this reaction, it is preferable to use a polymerization inhibitor such as, for example, hydroquinone, hydroquinone monomethyl ether, catechol, pt-butylcatechol, and phenothiazine in order to prevent radical polymerization by (meth) acryloyl group. The use amount of the polymerization inhibitor is preferably from 0.01 to 1% by weight, more preferably from 0.05 to 5% by weight, based on the reaction mixture.
In some cases, it is desirable to further add a solvent for the purpose of improving coatability.
[0069]
The solvent used may be various reaction solvents used in each of the production steps of the inorganic oxide fine particles, for example, the solvent used in the first step, or the solvent used in the second step. It may be a solvent used for the reaction. Further, it may be a solvent used for adjusting the viscosity.
[0070]
Next, inorganic oxide fine particles are hydrolyzed and condensed with the alkoxysilyl group of the polymer obtained in the second step to synthesize inorganic oxide fine particles having a predetermined structure (step 2-3).
[0071]
Here, as the inorganic oxide fine particles, the same ones as used when preparing the component (A) are used.
[0072]
In the reaction and bonding between the polymer obtained in the step 2-2 and the inorganic oxide fine particles, the mode of use of water, a catalyst, an organic solvent, and the like, the reaction mode, and the like are the same as those of the component (A).
[0073]
The reaction is carried out at 20 to 100 ° C. for 1 to 100 hours, preferably at 20 to 25 ° C. for 4 hours or more, followed by heating at 40 to 70 ° C. for 1 to 10 hours to advance the reaction. Further, the reaction system may be diluted with a solvent in order to suppress a side reaction. As the solvent to be used, water to be used and those having good compatibility with the catalyst are preferable, for example, alcohols such as methanol, ethanol, isopropanol and isobutanol, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, tetrahydrofuran and dioxane. And hydroxyl-containing ethers such as propylene glycol monomethyl ether.
The weight ratio between the alkoxysilyl group-containing polymer and the inorganic oxide fine particles (solid content) in the reaction system is preferably from 30/70 to 95/5, more preferably from 50/50 to 90/10. preferable. If the weight ratio of the inorganic component exceeds 70, stable inorganic oxide fine particles cannot be obtained, and if it is less than 5, the abrasion resistance tends to be insufficient.
[0074]
The composition of the present invention can be used as it is as a stain resistance imparting agent. However, for the purpose of improving the properties of the coating film, if necessary, for example, an ultraviolet absorber (for example, benzotriazole type, benzophenone type, salicylic acid type, cyanoacrylate type) UV absorbers), antioxidants (eg, hindered phenol, sulfur, phosphorus antioxidants), light stabilizers (eg, hindered amine light stabilizers), antiblocking agents, slip agents, leveling agents, etc. The various additives incorporated in the various compositions can be incorporated in the composition for forming the film in an amount of 0.01 to 2% by weight, respectively.
Further, for adjusting the viscosity of the stain resistance imparting agent (coating composition), the same organic solvent used in the production of the polymer can be used. In addition, if necessary, other polymers, radically polymerizable monomers, oligomers, and the like can be added within a range that does not impair the physical properties of the coating film that can be realized in the present invention.
[0075]
The stain resistance-imparting agent according to the present invention can be used, for example, on a plastic substrate such as a polyester such as polyethylene terephthalate and polyethylene naphthalate, a PMMA or MMA copolymer (for example, an MS resin), a polycarbonate, a triacetyl cellulose, and an ABS resin. , Dip coating, flow coating, spin coating, spray coating, bar coating, gravure coating, roll coating, blade coating, air knife coating, etc. The coating is performed under the condition that a coating layer of 1 to 50 μm, preferably 2 to 20 μm is obtained on the surface of the plastic substrate.
[0076]
The active energy ray irradiation method includes ultraviolet rays emitted from a light source such as a xenon lamp, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halide lamp, a carbon arc lamp, and a tungsten lamp, or electrons normally extracted from a 20 to 2000 kV particle accelerator. Irradiation with active energy rays such as X-rays, α-rays, β-rays, γ-rays, etc., and curing to form a film. A film cured by such active energy rays is excellent in balance between productivity and physical properties, and is particularly preferable.
[0077]
The coating film prepared by the above method using the stain resistance imparting agent according to the present invention has the following physical properties.
1) Pencil hardness
The stain resistance imparting agent is applied to a PET film having a thickness of 100 μm at a dry film thickness of 5 μm, and the cured coating has a pencil hardness of 5B or more. Further, when the stain resistance imparting agent contains an active energy ray-curable component, the pencil hardness is 2H or more, more preferably 3H or more.
2) Contact angle with water
The contact angle with water of the coating film obtained by applying and curing the stain resistance imparting agent is 80 degrees or more, preferably 85 degrees or more. If the angle is less than 80 degrees, the water repellency is low, so that the fingerprint and sebum wiping properties are particularly deteriorated, which is not preferable.
[0078]
3) Oleic acid, triolein (oleic acid triglyceride), squalene (one of acyclic triterpenes, a hydrocarbon having a chain structure composed of six isoprene residues. C) ₃₀ H ₅₀ ) Contact angle
The contact angles of the coatings obtained by applying and curing the stain resistance imparting agent to the above substances are all 10 degrees or less. It is more preferable that the angle is 5 degrees or less. If it exceeds 10 degrees, the lipophilicity is low, so that it is very conspicuous especially when a fingerprint or sebum adheres. That is, haze is greatly deteriorated and glossiness is also reduced.
When a fingerprint is adhered to the coating film thus obtained, it hardly adheres, or even if it adheres, it can be easily wiped off with a tissue or handkerchief in one operation. Also, sebum dirt (especially facial oil and nasal dirt), which has been a particular problem with conventional coatings and conventional water- and oil-repellent coatings, adheres to water- and oil-repellent coatings. While the change in haze at that time was as large as 10 to 20, the coating of the present invention was as small as 2 to 5 and was less noticeable even when adhered. On the other hand, with respect to the wiping properties, the water-repellent and oil-repellent coating film required a large number of times of 8 or more, whereas the coating film of the present invention required a small number of times of 4 or less so that it could be completely wiped off. (Slightly less noticeable after one or two wipings). Further, it is also possible to obtain a coating film which does not impair the transparency of the base material and is also excellent in scratch resistance and curling properties.
[0079]
Hereinafter, the present invention will be described in more detail with reference to Examples, Comparative Examples, and Reference Examples, but the present invention is not limited to these Examples. In the examples, parts and% mean parts by weight and% by weight, respectively.
The evaluation method of the coating film in Examples and the like is shown below.
(1) Transparency
The haze value was evaluated (JIS K-7105).
(2) Wear resistance
Using a worn wheel (manufactured by Caliberase: CS-10F), a 100-rotation Taber abrasion test was performed under a load of 500 g and evaluated by the difference ΔH (%) between the haze value after the Taber abrasion test and the haze value before the test.
(3) Pencil hardness
Using a JIS-compliant pencil hardness meter system (manufactured by Taiyo Kiki Co., Ltd.), the measurement was performed based on the conditions of JIS K-5400, and the measurement was indicated by the number of the hardest pencil that does not scratch.
(4) curl properties
The coating film was applied on a 10 cm square, and evaluated by the average value (mm) of the lift amounts of the four corners at the time of standing.
(5) Coating adhesion
The cross-cut method described in JIS K5400 (100 cross-cuts were inserted at 1 mm intervals and tested with cellophane tape (trade name, manufactured by Nichiban Co., Ltd.)) However, the same operation was repeated five times (cellophane tape was always new. The test was evaluated by changing the method to な い when no scratch or peeling occurred at all and to Δ when 10% or less of scratches or peeling occurred, and x for the others.
(6) Contact angle with water
0.002 ml of pure water was dropped on the coating film, and the contact angle after 1 minute was measured. The contact angle was measured using a P-type contact angle measuring device (manufactured by Kyowa Kagaku Co., Ltd.) (unit: degree).
(7) Contact angle for oleic acid, triolein and squalene
The contact angle was measured by the method described in (6) except that these solvents were used instead of pure water (unit: degree).
(8) Fingerprint stain resistance
Adhesion: Hold with palm and press slightly moistened thumb vertically onto coating for 3 seconds to fingerprint the coating.
Adhesion was evaluated by haze after fingerprint attachment.
Wipeability: The surface was lightly wiped with a commercially available tissue and evaluated by the number of times until fingerprint stains were not visually observed.
(9) Sebum stain resistance
Adhesion: Place the nose on your thumb and press the thumb vertically on the coating for 3 seconds to fingerprint the coating.
Adhesion was evaluated by haze after adhesion of nasal fat.
Wipeability: The surface was lightly wiped with a commercially available tissue, and evaluated by the number of times until sebum stains disappeared visually.
[0080]
[Reference Example 1] (Synthesis of stain resistance imparting agent 1)
40 g of methyl methacrylate, 20 g of stearyl methacrylate, and 200 g of methyl ethyl ketone (MEK) were stirred and mixed, and a polymerization initiator (2,2′-azobis (2,4-dimethylvaleronitrile), V-65, manufactured by Wako Pure Chemical Industries, Ltd.) Was added and the temperature was raised to 65 ° C. in a nitrogen stream, and the temperature was maintained for 5 hours (addition of 0.5 g of V-65 during the addition). Thereafter, the internal temperature was raised to 75 to 80 ° C., and maintained for 2 hours to completely decompose the remaining V-65. Thereafter, the mixture was cooled to room temperature to obtain a polymer having a solid content of 24% and a number average molecular weight of 18,000 (stain resistance imparting agent 1 = AF1).
[0081]
[Reference Example 2] (Synthesis of stain resistance imparting agent 2)
30 g of methyl methacrylate, 20 g of stearyl methacrylate, 10 g of polyethylene glycol monoacrylate (Blemmer AE400; manufactured by NOF Corporation) and 200 g of MEK were stirred and mixed, 0.5 g of V-65 was added, and the temperature was raised to 65 ° C. in a nitrogen stream, The temperature was maintained for 5 hours (additionally 0.5 g of V-65 was added on the way). Thereafter, the internal temperature was raised to 75 to 80 ° C., and maintained for 2 hours to completely decompose the remaining V-65. Thereafter, the mixture was cooled to room temperature to obtain a polymer having a solid content of 24% and a number average molecular weight of 17,000 (stain resistance imparting agent 2 = AF2).
[0082]
[Reference Example 3] (Synthesis of stain resistance imparting agent 3)
SH group obtained by starting from 2 g of mercaptopropyltrimethoxysilane (KBM803, manufactured by Shin-Etsu Chemical Co., Ltd.) and 70 g of MEK-dispersed organosilica sol having 30% solid content (MEK-ST, manufactured by Nissan Chemical Industries, Ltd.) Containing silica sol, 30 g of methyl methacrylate, 20 g of stearyl methacrylate, 10 g of polyethylene glycol monoacrylate (Blenmer AE400; manufactured by NOF CORPORATION), and 200 g of MEK are stirred and mixed, 0.5 g of V-65 is added, and the mixture is heated to 65 ° C under a nitrogen stream. The mixture was heated and maintained at that temperature for 5 hours (addition of 0.5 g of V-65 during the addition). Thereafter, the internal temperature was raised to 75 to 80 ° C., and maintained for 2 hours to completely decompose the remaining V-65. Thereafter, the mixture was cooled to room temperature to obtain a silica-containing polymer having a solid content of 26% (stain resistance imparting agent 3 = AF3).
[0083]
[Reference Example 4] (Synthesis of stain resistance imparting agent 4)
SH group-containing silica sol obtained by starting from 2 g of KBM803 and 100 g of an isopropanol-dispersed organosilica sol having a solid content of 20% (IPA-STUP, manufactured by Nissan Chemical Industries, Ltd.), 30 g of methyl methacrylate, 20 g of stearyl methacrylate, polyethylene glycol mono 10 g of acrylate (Blenmer AE400; manufactured by NOF Corporation) and 200 g of IPA were mixed with stirring, 0.5 g of V-65 was added, the temperature was raised to 65 ° C. in a nitrogen stream, and the temperature was maintained for 5 hours (on the way V-). 65 was added in an additional 0.5 g). Thereafter, the internal temperature was raised to 75 to 80 ° C., and maintained for 2 hours to completely decompose the remaining V-65. Thereafter, the mixture was cooled to room temperature, and a silica-containing polymer having a solid content of 25% was obtained (stain resistance imparting agent 4 = AF4).
[0084]
[Reference Example 5] (Synthesis of stain resistance imparting agent 5)
40 g of methyl methacrylate, 15 g of stearyl methacrylate, 5 g of tricyclodecene monomethanol methacrylate, 2 g of acrylic acid, and 200 g of MEK were stirred and mixed, 0.5 g of V-65 was added, and the temperature was raised to 65 ° C. under a nitrogen stream. The time was maintained (0.5 g of V-65 was added during the addition). Thereafter, the internal temperature was raised to 75 to 80 ° C., and maintained for 2 hours to completely decompose the remaining V-65. Thereafter, the mixture was cooled to room temperature to obtain a polymer having a solid content of 25% and a number average molecular weight of 19000 (stain resistance imparting agent 5 = AF5).
[0085]
[Reference Example 6] (Synthesis of silane coupling agent having polyfunctional acryloyl group by reaction of OH group-containing polyfunctional acrylate and NCO group-containing silane coupling agent)
1 kg of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd., Kayarad DPHA), 50 g of γ-triethoxysilylpropyl isocyanate (KBE9007, manufactured by Shin-Etsu Chemical Co., Ltd.), 0.2 g of dibutyltin dilaurate After stirring and mixing 0.5 g of hydroquinone monomethyl ether, the temperature was raised to 90 ° C. in an air stream and maintained at that temperature for 1 hour. It was confirmed by IR that the absorption corresponding to the NCO group had completely disappeared. Thereafter, the temperature was returned to room temperature, and the product was taken out. The reaction was quantitative. (Silane coupling agent 1 = SC1)
[0086]
[Reference Example 7] (Reaction of colloidal silica with a silane coupling agent having a polyfunctional acryloyl group)
400 g of MEK-dispersed organosilica sol (manufactured by Nissan Chemical Industries, Ltd., MEK-ST, solid content 30%), 400 g of silane coupling agent 1 (a mixture of a polyfunctional acryloyl group-containing silane coupling agent and an unreacted polyfunctional acrylate), After 0.4 g of hydroquinone monomethyl ether and 4 g of aluminum acetylacetone were mixed well, 8 g of pure water was added, and stirring was continued at room temperature for 3 hours or more. Thereafter, the temperature was raised to 50 to 70 ° C. in an air atmosphere, and stirring was continued for 2 hours or more at that temperature, and the surface of the silica sol was reacted with a silane coupling agent to form a protective colloid (treated colloidal silica 1 = SI1). .
[0087]
[Reference Example 8] (Synthesis of silane-terminated polymer and reaction with colloidal silica)
After 95 g of glycidyl methacrylate, 3 g of mercaptopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM803) and 200 g of propylene glycol monomethyl ether acetate (PGMAc) were mixed, the internal temperature was raised to about 60 ° C. under a nitrogen stream. Thereafter, V-65 was divided into two portions, a total of 1.5 g was added, and stirring was continued at 65 ° C for 6 hours. Thereafter, the internal temperature was raised to 100 ° C. to completely inactivate V-65, and then 200 g of PGMAc and 1.5 g of triphenylphosphine were added, and stirring was continued under an air atmosphere until the mixture became uniform. Thereafter, a mixture of 49 g of acrylic acid / 10 g of PGMAc was added over about 20 minutes, and then the internal temperature was raised to 110 ° C., and maintained and stirred for 8 hours or more to complete the reaction between the acrylic acid and the epoxy group. After the content mixture was returned to room temperature, 163 g of MEK-ST and 0.04 g of aluminum acetylacetonate were added. After stirring until the mixture became uniform, 0.99 g of pure water was added. The reaction was performed for 4 hours. Then, the internal temperature was returned to room temperature. The solid concentration was about 30% (treated colloidal silica 2 = SI2).
[0088]
[Reference Example 9] (Preparation of silane coupling agent described in JP-A-2001-353808)
2-Trichlorosilaneethyl stearate was decomposed with methanol to obtain 2-trimethoxysilylethyl stearate (silane coupling agent 2 = SC2).
[0089]
[Reference Example 10] (Preparation of stain resistance imparting agent outside the scope of the present invention)
40 g of methyl methacrylate, 20 g of stearyl methacrylate, 5 g of perfluorooctylethyl methacrylate and 200 g of MEK were stirred and mixed, 0.5 g of V-65 was added, the temperature was raised to 65 ° C. under a nitrogen stream, and the temperature was maintained for 5 hours (on the way). 0.5 g of V-65 was additionally added). Thereafter, the internal temperature was raised to 75 to 80 ° C., and maintained for 2 hours to completely decompose the remaining V-65. Thereafter, the mixture was cooled to room temperature to obtain a polymer having a solid content of 26% and a number average molecular weight of 18,000 (stain resistance imparting agent 6 = AF6).
[0090]
[Reference Example 11] (Preparation of stain resistance imparting agent outside the scope of the present invention)
40 g of methyl methacrylate, 20 g of stearyl methacrylate, 5 g of bismercaptopolydimethylsiloxane (manufactured by Shin-Etsu Chemical Co., Ltd .; X-22-167B), and 200 g of MEK were stirred and mixed, 0.5 g of V-65 was added, and a nitrogen gas flow at 65 ° C. The temperature was lowered and maintained at that temperature for 5 hours (addition of 0.5 g of V-65 during the addition). Thereafter, the internal temperature was raised to 75 to 80 ° C., and maintained for 2 hours to completely decompose the remaining V-65. Thereafter, the mixture was cooled to room temperature to obtain a polymer having a solid content of 26% and a number average molecular weight of 17000 (stain resistance imparting agent 7 = AF7).
[0091]
[Reference Example 12] (Preparation of stain resistance imparting agent outside the scope of the present invention)
40 g of methyl methacrylate, 20 g of n-decyl methacrylate, and 200 g of MEK were mixed with stirring, 0.5 g of V-65 was added, the temperature was raised to 65 ° C. in a nitrogen stream, and the temperature was maintained for 5 hours (the V-65 was reduced to 0%). .5 g). Thereafter, the internal temperature was raised to 75 to 80 ° C., and maintained for 2 hours to completely decompose the remaining V-65. Thereafter, the mixture was cooled to room temperature to obtain a polymer having a solid content of 24% and a number average molecular weight of 19000 (stain resistance imparting agent 8 = AF8).
[0092]
[Examples 1 to 12] and [Comparative Examples 1 to 7]
Each composition was prepared with the composition shown in Table 1. Using the composition, a coating film was formed by the following method and evaluated. The coating film was applied to a transparent (1.5% haze value) 100 micron thick polyethylene terephthalate film (manufactured by Mitsubishi Chemical Polyester Film Co., Ltd .: T600E) using a bar coater so that the film thickness after drying was 6 μm. And dried by heating at 80 ° C. for 2 minutes. Using a high-pressure mercury lamp with an output density of 120 W / cm, this film was tested for its transparency, abrasion resistance, pencil hardness, coating film adhesion, curl properties, and contact angle (water, squalene, oleic acid, triolein) resistance. Fingerprint stain resistance and sebum stain resistance were evaluated. Table 1 shows the composition of the composition, and Tables 2 and 3 show the evaluation results.
As is evident from the results, coating films exhibiting physical properties within the scope of the present invention are extremely excellent in fingerprint stain resistance and sebum stain resistance, but coating films exhibiting physical properties outside the scope of the present invention are: It was clear that the fingerprint stain resistance and sebum stain resistance were inferior, and in particular, the sebum stain resistance was significantly inferior to a coating film showing physical properties within the range of the present invention.
[0093]
[Table 1]

DPHA: dipentaerythritol hexa / pentaacrylate (Nippon Kayaku Co., Ltd.)
DPHA *: DPHA in SI1
U15HA: Polyfunctional urethane acrylate (Shin-Nakamura Chemical Co., Ltd.)
SI1 / SI2: compounding ratio (solid content) 2/1
I184: Irgacure 184 (manufactured by Ciba Specialty Chemicals Co., Ltd.)
Note: Solvent is a mixed solvent of MEK, PGM, PGMAc, IPA
[0094]
[Table 2]

[0095]
[Table 3]

[0096]
[Comparative Example 8]
SC2 was hydrolyzed with 1.2 times the calculated amount of water in the presence of an ethanol / aluminum triacetylacetone catalyst to obtain a condensate.
On a PET film having a thickness of 100 μm (haze = 1.5%), a coating film described in Comparative Example 1 was formed at a thickness of 6 μm, and the above condensate was applied so that the thickness after drying became 0.1 μm. At 100 ° C. for 5 minutes to form an antifouling coating on the surface.
The physical properties of the coating film were as follows: haze = 1.6%, abrasion resistance = 5.1%, pencil hardness H, curl property 2 mm, adhesion △, contact angle = (water) 83 degrees, (squalene) 10 degrees, ( (Oleic acid) 7 °, (triolein) 10 °, fingerprint stain resistance: haze at the time of adhesion = 3.2% / wiping property = 2 times, sebum resistance: haze at the time of adhesion = 6.6% / Wipeability = 6 times, and the initial fingerprint stain resistance and sebum stain resistance are slightly inferior to those of the coating film within the scope of the present invention, but the general antifouling / fingerprint stain resistant coating agent Good compared to coatings. However, since the pencil hardness is low and the adhesiveness is poor, repeated evaluation of fingerprint stain resistance and sebum stain resistance results in the formation of fine scratches and peeling of the coating film, and the stain resistance is reduced. It was clear that there was a major problem.
[0097]
[Examples 13 to 15] and [Comparative Examples 9 to 12]
Component (A) shown in Table 4 was used alone to form a coating film so that the film thickness after drying was about 2 μm. The coating base material, coating method, drying method, etc. were performed in the same manner as in Example 1, and the coating film properties were evaluated. Table 4 shows the evaluation results.
As is clear from the results in Table 4, the components of Examples 13 to 15 are excellent in fingerprint stain resistance, so that the components that do not require much hardness (for example, fingerprint stain resistance on products requiring flexibility) Can be used without any problem.
[0098]
[Table 4]

[0099]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to the stain resistance imparting agent of this invention, preparation of a coating film which has very high levels of fingerprint stain resistance and sebum stain resistance can be realized. Further, the composition contains polyfunctional acrylate or inorganic oxide fine particles having a group having a (meth) acryloyl group bonded to the surface of the inorganic oxide fine particles via an -O-Si-R- bond. At the same time, it can have excellent hardness, scratch resistance, transparency, low curl, etc., and can be suitably used for a wide range of applications such as touch panels, displays, mobile phone housings, and optical disks.
That is, when the stain resistance imparting agent of the present invention is applied to a typical transparent substrate such as PET, TAC, or PMMA, the pencil hardness is as high as 2H or more, and the contact angle with water at the same time is 80 degrees. By exhibiting water repellency as described above, adhesion of hydrophilic stains is prevented, while on the other hand, typical sebum components such as oleic acid, triolein, and squalene have a contact angle of 10 degrees or less and exhibit lipophilicity. Wet, inconspicuous when attached. On the other hand, since the contact angle with water is high, fingerprints and sebum (although water is also present, oil-soluble components with a lower specific gravity than water float on the surface and eventually come into direct contact with the coating film) Excessive adaptation is suppressed, and excellent wiping properties are provided. Furthermore, the combination of a water-repellent group and a hydrophilic group further enhances the effect and further improves the wiping properties, thus realizing a high level of fingerprint stain resistance and sebum stain resistance that could not be achieved conventionally. it can.

Claims (13)

The pencil hardness of the coating film formed from the stain resistance imparting agent is 5B or more, the contact angle to water is 80 degrees or more, and the contact angles to oleic acid, triolein and squalene are all 10 degrees or less. The stain resistance-imparting agent described above. The (meth) acrylic copolymer (A) (A) wherein the stain resistance imparting agent contains a (meth) acrylate having a water-repellent group containing neither an organo (poly) siloxane group nor an organic fluorine compound group as a copolymer component. The stain resistance-imparting agent according to claim 1, which comprises a component (A), or a composite of the component (A) and inorganic oxide fine particles. The stain resistance-imparting agent according to claim 2, wherein the water-repellent group is an alkyl group having 12 or more carbon atoms or a polycycloalkyl group. Claims wherein the component (A) comprises, as copolymerization components, a (meth) acrylate having a water-repellent group containing neither an organo (poly) siloxane group nor an organic fluorine compound group, and a (meth) acrylate having a hydrophilic group. Item 6. The stain resistance-imparting agent according to Item 2 or 3. The stain resistance imparting agent according to claim 4, wherein the hydrophilic group is at least one group selected from the group consisting of a polyalkylene glycol group, a hydroxyl group, a carboxylic acid group, a sulfonic acid group, a phosphoric acid group, and salts thereof. The stain resistance imparting agent according to any one of claims 2 to 5, wherein the component (A) is bound to colloidal silica or inorganic oxide fine particles containing the same as a main component. The pencil hardness of the coating film formed from the stain resistance imparting agent is 2H or more, the contact angle with water is 80 degrees or more, and the contact angles with oleic acid, triolein and squalene are all 10 degrees or less. Characteristic active energy ray-curable stain resistant agent. The active energy ray-curable stain resistance-imparting agent according to claim 7, comprising a component (A), a polyfunctional (meth) acrylate compound (B) and a photopolymerization initiator (C). On the surface of the component (A), the polyfunctional (meth) acrylate compound (B), the photopolymerization initiator (C), and the surface of the inorganic oxide fine particles, an —O—Si—R— bond (R is a carbon number of 2 to 10) The active energy ray-curable composition according to claim 7 or 8, which comprises inorganic oxide fine particles (D) in which a group having a (meth) acryloyl group is bonded via a linear or branched alkylene group. Stain resistance imparting agent. A stain resistant article having on its surface a coating film formed from the stain imparting agent according to claim 1. A stain resistant article having on its surface a coating film formed from the active energy ray-curable stain resistant agent according to claim 7. The coating obtained by applying the active energy ray-curable stain resistance imparting agent according to claim 8 or 9 to the surface of a metal, glass, ceramics, or resin film, sheet, or molded article, and irradiating with an active energy ray to cure the coating. A stain-resistant article having a film. The pencil hardness of the coating film formed from the active energy ray-curable resin composition is 2H or more, the contact angle with water is 80 ° or more, and the contact angles with oleic acid, triolein and squalene are all 10 ° or less. The active energy ray-curable resin composition described above.