JP2005029685A - Water-based coating material for protecting soft groundwork - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water-based coating material for protecting soft groundwork, forming a coating film having highly balanced followingness to the soft groundwork, stain resistance, weather resistance and water resistance. <P>SOLUTION: The water-based coating material for protecting the soft groundwork contains a polymer comprising a monomer unit (A) containing silicon, and a monomer unit (B) derived from a monomer in which the solubility of water is ≤0.5 at 20°C, a homopolymer of which has ≤25°C glass transition temperature, and which does not contain the silicon. The polymer preferably has 50-99 mass% content of the monomer unit (B). The monomer constituting the monomer unit (B) is preferably the one whose homopolymer has ≤0°C glass transition temperature. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００１４】
本発明において用いる他の単量体としては、例えば、メチル（メタ）アクリレート、エチル（メタ）アクリレート、ｉ−ブチルメタアクリレート、ｓｅｃ−ブチルメタアクリレート、ｔ−ブチルメタアクリレート等のアルキル（メタ）アクリレート類；シクロヘキシルメタアクリレート、等のシクロアルキルメタアクリレート類；２−ヒドロキシエチル（メタ）アクリレート、２−ヒドロキシプロピル（メタ）アクリレート、３−ヒドロキシプロピル（メタ）アクリレート、４−ヒドロキシブチル（メタ）アクリレート、グリセロールモノ（メタ）アクリレート等のヒドロキシアルキル（メタ）アクリレート類；ヒドロキシポリエチレンオキシドモノ（メタ）アクリレート、ヒドロキシポリプロピレンオキシドモノ（メタ）アクリレート、ヒドロキシ（ポリエチレンオキシド−ポリプロピレンオキシド）モノ（メタ）アクリレート、ヒドロキシポリ（エチレンオキシド／プロピレンオキシド）モノ（メタ）アクリレート、ヒドロキシ（ポリエチレンオキシド−ポリテトラメチレンオキシド）モノ（メタ）アクリレート、ヒドロキシポリ（エチレンオキシド／テトラメチレンオキシド）モノ（メタ）アクリレート、ヒドロキシ（ポリプロピレンオキシド−ポリテトラメチレンオキシド）モノ（メタ）アクリレート、ヒドロキシポリ（プロピレンオキシド／テトラメチレンオキシド）モノ（メタ）アクリレート、メトキシポリエチレンオキシドモノ（メタ）アクリレート、ラウロキシポリエチレンオキシドモノ（メタ）アクリレート、ステアロキシポリエチレンオキシドモノ（メタ）アクリレート、アリロキシポリエチレンオキシドモノ（メタ）アクリレート、ノニルフェノキシポリエチレンオキシドモノ（メタ）アクリレート、ノニルフェノキシポリプロピレンオキシドモノ（メタ）アクリレート、オクトキシ（ポリエチレンオキシド−ポリプロピレンオキシド）モノ（メタ）アクリレート、ノニルフェノキシポリ（エチレンオキシド／プロピレンオキシド）モノ（メタ）アクリレート等のポリアルキレンオキシド基含有（メタ）アクリレート類；ｐ−ヒドロキシシクロヘキシル（メタ）アクリレート等のヒドロキシシクロアルキル（メタ）アクリレート類；ラクトン変性ヒドロキシアルキル（メタ）アクリレート類；２−アミノエチル（メタ）アクリレート、２−ジメチルアミノエチル（メタ）アクリレート、２−アミノプロピル（メタ）アクリレート、２−ブチルアミノエチル（メタ）アクリレート等のアミノアルキル（メタ）アクリレート類；（メタ）アクリルアミド、Ｎ−メチロールアクリルアミド、Ｎ−ブトキシメチル（メタ）アクリルアミド等のアミド基含有重合性単量体；エチレングリコールジ（メタ）アクリレート、プロピレングリコールジ（メタ）アクリレート、ブチレングリコールジ（メタ）アクリレート、トリメチロールプロパントリ（メタ）アクリレート等の多官能性（メタ）アクリレート類；２−（２’−ヒドロキシ−５’−（メタ）アクリロキシエチルフェニル）−２Ｈ−ベンゾトリアゾールや、１−（メタ）アクリロイル−４−ヒドロキシ−２，２，６，６−テトラメチルピペリジン、１−（メタ）アクリロイル−４−メトキシ−２，２，６，６−テトラメチルピペリジン、１−（メタ）アクリロイル−４−アミノ−４−シアノ−２，２，６，６−テトラメチルピペリジン等の耐紫外線基含有（メタ）アクリリレート；ジ（メタ）アクリル酸亜鉛等の金属含有ラジカル重合性単量体；ジメチルアミノエチル（メタ）アクリレートメチルクロライド塩、グリシジル（メタ）アクリレート、（メタ）アクリロニトリル、フェニル（メタ）アクリレート、イソボルニル（メタ）アクリレート、テトラヒドロフルフリル（メタ）アクリレート、メトキシエチル（メタ）アクリレート、エトキシエチル（メタ）アクリレート等の他の（メタ）アクリル系単量体；アクロレイン、ジアセトンアクリルアミド、ホルミルスチロール、ビニルメチルケトン、ビニルエチルケトン、ビニルイソブチルケトン、ピバリンアルデヒド、ジアセトン（メタ）アクリレート、アセトニルアクリレート、アセトアセトキシエチル（メタ）アクリレート等のアルデヒド基またはケト基に基づくカルボニル基含有単量体；スチレン、メチルスチレン、クロロスチレン、メトキシスチレン等の芳香族ビニル系単量体；１，３−ブタジエン、イソプレン、２−クロル−１，３−ブタジエン等の共役ジエン系単量体；（メタ）アクリル酸や、イタコン酸、フマル酸、マレイン酸やそのハーフエステル等、２−（メタ）アクリロキシエチルフタル酸、２−（メタ）アクリロキシエチルヘキサヒドロフタル酸等のカルボキシル基含有単量体；酢酸ビニル、塩化ビニル、エチレン、プロピオン酸ビニル等が挙げられるが、ラジカル重合可能なものであればこれらに限られるものではない。
上記単量体の内、特に、ｔ−ブチルメタクリレートとシクロヘキシルメタクリレートとを組み合わせて用いることが好ましい。この含有量は、全重合体中を２〜４９質量％の範囲内とすることが好ましい。この含有量が２質量％以上であると、塗膜の耐水性および耐候性が向上し、４９質量％以下であると、塗膜の柔軟性の低下を抑制できる。より好ましい含有量は、５〜４０質量％である。
【００１５】
本発明においては、単量体の２０℃における単量体に対する水の溶解度が０．５以下であることにより塗膜の耐候性、耐水性が向上し、ホモポリマーのガラス転移温度が２５℃以下であることにより塗膜の柔軟性が向上する。
これらの２つの条件を満たす単量体単位を、全重合体中５０〜９９質量％の範囲内で含有することにより、塗膜の柔軟性、耐候性、耐水性を向上することができる。
この含有量が５０質量％以上であると、塗膜の柔軟性が向上し、９９質量％以下であると、塗膜の耐汚染性、耐候性、耐水性の低下を抑制できる。より好ましい含有量は、５５〜９０質量％である。
特に、ホモポリマーのガラス転移温度が０℃以下である単量体を使用することにより塗膜の柔軟性がさらに向上する。その含有量は全重合体中３５〜９０質量％であることが好ましい。さらに好ましい含有量は４０〜８０質量部％である。
【００１６】
本発明においては、重合体水分散液の貯蔵安定性、顔料や添加物を入れ塗料化する際の配合安定性の点から、他の単量体として、エチレン性不飽和カルボン酸単量体を含有することが好ましい。この含有量は、全重合体中０．１〜１０質量％の範囲内が好ましい。この含有量が０．１質量％以上であるとビニル系共重合体水分散液の貯蔵安定性が向上し、本発明の水性被覆材に顔料を入れて着色した場合、凝集物が発生するような問題を回避することができる。また、この含有量が１０質％部以下であると、塗膜の耐水性および耐候性の低下を抑制できる。より好ましい含有量は、０．５〜８質量％である。
このエチレン性不飽和カルボン酸単量体としては、例えば、（メタ）アクリル酸、イタコン酸、シトラコン酸、マレイン酸、マレイン酸モノメチル、マレイン酸モノブチル、イタコン酸モノメチル、イタコン酸モノブチル、ビニル安息香酸、シュウ酸モノヒドロキシエチル（メタ）アクリレート、テトラヒドロフタル酸モノヒドロキシエチル（メタ）アクリレート、テトラヒドロフタル酸モノヒドロキシプロピル（メタ）アクリレート、５−メチル−１，２−シクロヘキサンジカルボン酸モノヒドロキシエチル（メタ）アクリレート、フタル酸モノヒドロキシエチル（メタ）アクリレート、フタル酸モノヒドロキシプロピル（メタ）アクリレート、マレイン酸モノヒドロキシエチル（メタ）アクリレート、マレイン酸ヒドロキシプロピル（メタ）アクリレート、テトラヒドロフタル酸モノヒドロキシブチル（メタ）アクリレート等が挙げられる。これらは必要に応じて１種以上を適宜選択して使用できる。
【００１７】
また、重合体水分散液の配合安定性や塗膜の耐汚染性、耐候性、耐水性、および各種下地に対する密着性の点から、他の単量体としてヒドロキシアルキル（メタ）アクリレートを含有することが好ましい。この含有量は、全重合体中０．１〜１５質量％の範囲内が好ましい。この含有量が０．１質量％以上であるとビニル系共重合体水分散液の配合安定性や塗膜の耐汚染性、耐候性、耐水性、および各種下地に対する密着性が向上し、１５質量％以下であると塗膜の耐水性および耐候性の低下を抑制できる。より好ましい含有量は、０．５〜１２質量％である。
ヒドロキシアルキル（メタ）アクリレートとしては、例えば、ヒドロキシメチル（メタ）アクリレート、２−ヒドロキシエチル（メタ）アクリレート、２−ヒドロキシプロピル（メタ）アクリレート、３−ヒドロキシプロピル（メタ）アクリレート、４−ヒドロキシブチル（メタ）アクリレート、６−ヒドロキシヘキシル（メタ）アクリレー等が挙げられる。これらは必要に応じて１種以上を適宜選択して使用できる。
【００１８】
また、ビニル系共重合体水分散液の配合安定性や塗膜の耐汚染性、耐候性、耐水性、および各種下地に対する密着性の点から、他の単量体として、ポリオキシアルキレン基含有（メタ）アクリレートを含有することが好ましい。この含有量は、全重合体中、０．１〜１５質量％の範囲内が好ましい。この含有量が０．１質量％以上であるとビニル系共重合体水分散液の配合安定性や塗膜の耐汚染性、耐候性、耐水性、および各種下地に対する密着性が向上し、１５質量％以下であると塗膜の耐水性および耐候性の低下を抑制できる。より好ましい含有量は、０．５〜１２質量％である。
ポリオキシアルキレン基含有（メタ）アクリレートとしては、例えば、ヒドロキシポリエチレンオキシドモノ（メタ）アクリレート、ヒドロキシポリプロピレンオキシドモノ（メタ）アクリレート、ヒドロキシ（ポリエチレンオキシド−ポリプロピレンオキシド）モノ（メタ）アクリレート、ヒドロキシポリ（エチレンオキシド／プロピレンオキシド）モノ（メタ）アクリレート、ヒドロキシ（ポリエチレンオキシド−ポリテトラメチレンオキシド）モノ（メタ）アクリレート、ヒドロキシポリ（エチレンオキシド／テトラメチレンオキシド）モノ（メタ）アクリレート、ヒドロキシ（ポリプロピレンオキシド−ポリテトラメチレンオキシド）モノ（メタ）アクリレート、ヒドロキシポリ（プロピレンオキシド／テトラメチレンオキシド）モノ（メタ）アクリレート等の末端ヒドロキシ型ポリアルキレンオキシド基含有エチレン性不飽和単量体や、メトキシポリエチレンオキシドモノ（メタ）アクリレート、ラウロキシポリエチレンオキシドモノ（メタ）アクリレート、ステアロキシポリエチレンオキシドモノ（メタ）アクリレート、アリロキシポリエチレンオキシドモノ（メタ）アクリレート、ノニルフェノキシポリエチレンオキシドモノ（メタ）アクリレート、ノニルフェノキシポリプロピレンオキシドモノ（メタ）アクリレート、オクトキシ（ポリエチレンオキシド−ポリプロピレンオキシド）モノ（メタ）アクリレート、ノニルフェノキシ（ポリエチレンオキシド−プロピレンオキシド）モノ（メタ）アクリレート等のアルキル基末端封止型ポリアルキレンオキシド基含有エチレン性不飽和単量体が挙げられる。これらは必要に応じて１種以上を適宜選択して使用できる。
【００１９】
また、塗膜の耐汚染性、耐候性、耐水性、および各種下地に対する密着性の点から、他の単量体として、自己架橋性官能基含有エチレン性不飽和単量体を含有することが好ましい。この含有量は、全重合体中０．１〜１５質量％の範囲内が好ましい。この含有量が０．１質量％以上であると塗膜の耐汚染性、耐候性、耐水性、および各種下地に対する密着性が向上し、１５質量％以下であると塗膜の耐水性および耐候性の低下を抑制できる。より好ましい含有量は、０．５〜１２質量％である。
ここで、自己架橋性官能基含有エチレン性不飽和単量体とは、樹脂が樹脂分散液中に分散し、室温で保管されている間は化学的に安定であって、塗装時の乾燥、加熱あるいはその他の外的要因によって側鎖官能基同士の反応を生じ、該側鎖基間に化学結合を生じるような官能基を有するエチレン性不飽和単量体を指す。
自己架橋性官能基含有エチレン性不飽和単量体としては、例えば、グリシジル（メタ）アクリレート等のオキシラン基含有エチレン性不飽和単量体、Ｎ−メチロール（メタ）アクリルアミド、Ｎ−ブトキシメチル（メタ）アクリルアミド、Ｎ−メトキシメチル（メタ）アクリルアミド等のエチレン性不飽和アミドのアルキロールまたはアルコキシアルキル化合物が挙げられる。これらは必要に応じて１種以上を適宜選択して使用できる。
【００２０】
また、塗膜の耐候性の点から、ケイ素を含有しない単量体として、耐紫外線エチレン性不飽和単量体を含有することが好ましい。この含有量は、全重合体中０．１〜１０質量％の範囲内が好ましい。この含有量が０．１質量％以上であると塗膜の耐候性が向上し、１０質量％以下であると重合安定性の低下を抑制できる。より好ましい含有量は、０．５〜８質量％である。
耐紫外線エチレン性不飽和単量体としては、代表的には、光安定化作用を有する（メタ）アクリレート、紫外線吸収性成分を有する（メタ）アクリレートが挙げられる。
光安定化作用を有する（メタ）アクリレートとしては、例えば、４−（メタ）アクリロイルオキシ−２，２，６，６−テトラメチルピペリジン、４−（メタ）アクリロイルアミノ−２，２，６，６−テトラメチルピペリジン、４−（メタ）アクリロイルオキシ−１，２，２，６，６−ペンタメチルピペリジン、４−（メタ）アクリロイルアミノ−１，２，２，６，６−ペンタメチルピペリジン、４−シアノ−４−（メタ）アクリロイルオキシ−２，２，６，６−トラメチルピペリジン等が挙げられる。
紫外線吸収性成分を有する（メタ）アクリレートとしては、例えば、２−［２−ヒドロキシ−５−（メタ）アクリロイルオキシエチルフェニル］−２Ｈ−ベンゾトリアゾール、２−［２−ヒドロキシ−３−ｔ−ブチル−５−（メタ）アクリロイルオキシエチルフェニル］−２Ｈ−ベンゾトリアゾール、２−［２−ヒドロキシ−３−ｔ−アミル−５−（メタ）アクリロイルオキシエチルフェニル］−２Ｈ−ベンゾトリアゾール等が挙げられる。
これら耐紫外線エチレン性不飽和単量体は必要に応じて１種以上を適宜選択して使用できる。
また、耐汚染性がより高度に要求される場合や、可塑剤を有している軟質下地で、この可塑剤のブリードアウトにより塗膜の汚染性が低下する場合には、ケイ素を含有しない単量体として金属含有ラジカル重合性単量体や、また特定の架橋システムを導入することも好ましい態様である。
本発明において使用される金属含有ラジカル重合性単量体としては、下記一般式（Ｉ）で表される金属含有重合性単量体が示される。
【００２１】
【化１】

（式中、Ｒ^１は水素原子またはメチル基、ＭはＭｇ、Ｃａ、Ｆｅ、Ｃｕ、Ｚｎ、Ｚｒ等の２価の金属イオン、Ｒ^２は有機酸残基を示す。）
【００２２】
なお、有機酸残基が（メタ）アクリル酸残基であるときは、２個の不飽和基を有する金属含有重合性単量体であり、具体的には、例えば、ジアクリル酸マグネシウム、ジメタクリル酸マグネシウム、アクリル酸メタクリル酸マグネシウム、ジアクリル酸カルシウム、ジメタクリル酸カルシウム、アクリル酸メタクリル酸カルシウム、ジアクリル酸鉄、ジメタクリル酸鉄、アクリル酸メタクリル酸鉄、ジアクリル酸銅、ジメタクリル酸銅、アクリル酸メタクリル酸銅、ジアクリル酸亜鉛、ジメタクリル酸亜鉛、アクリル酸メタクリル酸亜鉛、ジアクリル酸ジルコニウム、ジメタクリル酸ジルコニウム、アクリル酸メタクリル酸ジルコニウム等が好ましい。
金属含有重合性単量体のＲ^２が（メタ）アクリル酸残基以外の有機酸残基であるとき、好ましい有機酸残基として、モノクロル酢酸、モノフルオロ酢酸、プロピオン酸、オクチル酸、バーサチック酸、イソステアリン酸、パルミチン酸、クレソチン酸、α−ナフトエ酸、β−ナフトエ酸、安息香酸、２，４，５−トリクロロフェノキシ酢酸、２，４−ジクロロフェノキシ酢酸、キノリンカルボン酸、ニトロ安息香酸、ニトロナフタレンカルボン酸、プルビン酸等の一価の有機酸から誘導されるものが例示される。
すなわち、この金属含有重合性単量体の具体例としては、例えば、モノクロル酢酸マグネシウム（メタ）アクリレート、モノクロル酢酸カルシウム（メタ）アクリレート、モノクロル酢酸鉄（メタ）アクリレート、モノクロル酢酸銅（メタ）アクリレート、モノクロル酢酸亜鉛（メタ）アクリレート、モノクロル酢酸ジルコニウム（メタ）アクリレート、モノフルオロ酢酸マグネシウム（メタ）アクリレート、モノフルオロ酢酸カルシウム（メタ）アクリレート、モノフルオロ酢酸鉄（メタ）アクリレート、モノフルオロ酢酸銅（メタ）アクリレート、モノフルオロ酢酸亜鉛（メタ）アクリレート、モノフルオロ酢酸ジルコニウム（メタ）アクリレート、プロピオン酸マグネシウム（メタ）アクリレート、プロピオン酸カルシウム（メタ）アクリレート、プロピオン酸鉄（メタ）アクリレート、プロピオン酸銅（メタ）アクリレート、プロピオン酸亜鉛（メタ）アクリレート、プロピオン酸ジルコニウム（メタ）アクリレート、オクチル酸マグネシウム（メタ）アクリレート、オクチル酸カルシウム（メタ）アクリレート、オクチル酸鉄（メタ）アクリレート、オクチル酸銅（メタ）アクリレート、オクチル酸亜鉛（メタ）アクリレート、オクチル酸ジルコニウム（メタ）アクリレート、バーサチック酸マグネシウム（メタ）アクリレート、バーサチック酸カルシウム（メタ）アクリレート、バーサチック酸鉄（メタ）アクリレート、バーサチック酸銅（メタ）アクリレート、バーサチック酸亜鉛（メタ）アクリレート、バーサチック酸ジルコニウム（メタ）アクリレート、イソステアリン酸マグネシウム（メタ）アクリレート、イソステアリン酸カルシウム（メタ）アクリレート、イソステアリン酸鉄（メタ）アクリレート、イソステアリン酸銅（メタ）アクリレート、イソステアリン酸亜鉛（メタ）アクリレート、イソステアリン酸ジルコニウム（メタ）アクリレート、パルミチン酸マグネシウム（メタ）アクリレート、パルミチン酸カルシウム（メタ）アクリレート、パルミチン酸鉄（メタ）アクリレート、パルミチン酸銅（メタ）アクリレート、パルミチン酸亜鉛（メタ）アクリレート、パルミチン酸ジルコニウム（メタ）アクリレート、クレソチン酸マグネシウム（メタ）アクリレート、クレソチン酸カルシウム（メタ）アクリレート、クレソチン酸鉄（メタ）アクリレート、クレソチン酸銅（メタ）アクリレート、クレソチン酸亜鉛（メタ）アクリレート、クレソチン酸ジルコニウム（メタ）アクリレート、α−ナフトエ酸マグネシウム（メタ）アクリレート、α−ナフトエ酸カルシウム（メタ）アクリレート、α−ナフトエ酸鉄（メタ）アクリレート、α−ナフトエ酸銅（メタ）アクリレート、α−ナフトエ酸亜鉛（メタ）アクリレート、α−ナフトエ酸ジルコニウム（メタ）アクリレート、β−ナフトエ酸マグネシウム（メタ）アクリレート、β−ナフトエ酸カルシウム（メタ）アクリレート、β−ナフトエ酸鉄（メタ）アクリレート、β−ナフトエ酸銅（メタ）アクリレート、β−ナフトエ酸亜鉛（メタ）アクリレート、β−ナフトエ酸ジルコニウム（メタ）アクリレート、安息香酸マグネシウム（メタ）アクリレート、安息香酸カルシウム（メタ）アクリレート、安息香酸鉄（メタ）アクリレート、安息香酸銅（メタ）アクリレート、安息香酸亜鉛（メタ）アクリレート、安息香酸ジルコニウム（メタ）アクリレート、２，４，５−トリクロロフェノキシ酢酸マグネシウム（メタ）アクリレート、２，４，５−トリクロロフェノキシ酢酸カルシウム（メタ）アクリレート、２，４，５−トリクロロフェノキシ酢酸鉄（メタ）アクリレート、２，４，５−トリクロロフェノキシ酢酸銅（メタ）アクリレート、２，４，５−トリクロロフェノキシ酢酸亜鉛（メタ）アクリレート、２，４，５−トリクロロフェノキシ酢酸ジルコニウム（メタ）アクリレート、２，４−ジクロロフェノキシ酢酸マグネシウム（メタ）アクリレート、２，４−ジクロロフェノキシ酢酸カルシウム（メタ）アクリレート、２，４−ジクロロフェノキシ酢酸鉄（メタ）アクリレート、２，４−ジクロロフェノキシ酢酸銅（メタ）アクリレート、２，４−ジクロロフェノキシ酢酸亜鉛（メタ）アクリレート、２，４−ジクロロフェノキシ酢酸ジルコニウム（メタ）アクリレート、キノリンカルボン酸マグネシウム（メタ）アクリレート、キノリンカルボン酸カルシウム（メタ）アクリレート、キノリンカルボン酸鉄（メタ）アクリレート、キノリンカルボン酸銅（メタ）アクリレート、キノリンカルボン酸亜鉛（メタ）アクリレート、キノリンカルボン酸ジルコニウム（メタ）アクリレート、ニトロ安息香酸マグネシウム（メタ）アクリレート、ニトロ安息香酸カルシウム（メタ）アクリレート、ニトロ安息香酸鉄（メタ）アクリレート、ニトロ安息香酸銅（メタ）アクリレート、ニトロ安息香酸亜鉛（メタ）アクリレート、ニトロ安息香酸ジルコニウム（メタ）アクリレート、ニトロナフタレンカルボン酸マグネシウム（メタ）アクリレート、ニトロナフタレンカルボン酸カルシウム（メタ）アクリレート、ニトロナフタレンカルボン酸鉄（メタ）アクリレート、ニトロ安息香酸銅（メタ）アクリレート、ニトロ安息香酸亜鉛（メタ）アクリレート、ニトロ安息香酸ジルコニウム（メタ）アクリレート、プルビン酸マグネシウム（メタ）アクリレート、プルビン酸カルシウム（メタ）アクリレート、プルビン酸鉄（メタ）アクリレートプルビン酸銅（メタ）アクリレート、プルビン酸亜鉛（メタ）アクリレート、プルビン酸ジルコニウム（メタ）アクリレート等が挙げられる。
これら金属含有重合性単量体は、１種または２種以上を必要に応じて適宜選択して使用することができるが、中でも、亜鉛含有重合性単量体が好ましい。
金属含有ラジカル重合性単量体は、ビニル系共重合体を構成する全単量体を１００質量部とするとき、０．１〜１０質量部の範囲内で含有されていることが好ましい。この含有量が０．１質量部以上であると塗膜の耐汚染性が向上し、１０質量部以下であると塗膜の耐水性および耐候性の低下を抑制できる。より好ましい含有量は、０．５〜８質量部である。
【００２３】
さらに本発明では、塗膜の耐汚染性、耐候性、耐水性、強度、耐溶剤性および各種下地に対する密着性の点から、カルボニル基および／またはアルデヒド基含有エチレン性不飽和単量体を使用し、このビニル系共重合体水分散液に、分子中に少なくとも２個のヒドラジノ基を有する有機ヒドラジン化合物を配合することがより好ましい。これは、塗膜の乾燥時に、ビニル系共重合体中のカルボニル基と、配合された有機ヒドラジン化合物のヒドラジノ基との間で架橋反応が進行し、さらに優れた塗膜の耐汚染性、耐候性、耐水性、強度、耐溶剤性および各種下地に対する密着性が得られるためである。
カルボニル基またはアルデヒド基含有エチレン性不飽和単量体としては、例えば、アクロレイン、ジアセトンアクリルアミド、ホルミルスチロール、ビニルアルキルケトン等があり、好ましくは、炭素数４〜７個のビニルメチルケトン、ビニルエチルケトン、ビニルイソブチルケトン、（メタ）アクリルオキシアルキルプロパナールの他、（メタ）アクリルアミド、ピバリンアルデヒド、ジアセトン（メタ）アクリレート、アセトニルアクリレート、アセトアセトキシエチル（メタ）アクリレート等が挙げられるが、中でも、アクロレイン、ジアセトンアクリルアミド、ビニルメチルケトンが特に好ましい。これらは、必要に応じて１種以上を適宜選択して使用することができる。
ビニル系共重合体水分散液に配合される分子中に少なくとも２個のヒドラジノ基を有する有機ヒドラジン化合物としては、例えば、エチレン−１，２−ジヒドラジン、プロピレン−１，３−ジヒドラジン、ブチレン−１，４−ジヒドラジン、シュウ酸ジヒドラジド、マロン酸ジヒドラジド、コハク酸ジヒドラジド、グルタル酸ジヒドラジド、アジピン酸ジヒドラジド、セバシン酸ジヒドラジド、マレイン酸ジヒドラジド、フマル酸ジヒドラジド、イソフタル酸ジヒドラジド、イタコン酸ジヒドラジド等の炭素数２〜１５のジカルボン酸のジヒドラジドおよび１，３−ビス（ヒドラジノカルボエチル）−５−イソプロピルヒダントイン、１，３−ビス（ヒドラジノカルボエチル）−５−（２−メチルメルカプトエチル）ヒダントイン、１−ヒドラジノカルボエチル−３−ヒドラジノカルボイソプロピル−５−（２−メチルメルカプトエチル）ヒダントイン等のヒダントイン骨格を有する有機ヒドラジン化合物が挙げられる。これらは必要に応じて１種以上を適宜選択して使用できる。中でも、塗膜の耐汚染性の点から、ヒダントイン骨格を有する有機ヒドラジン化合物が好ましく、１，３−ビス（ヒドラジノカルボエチル）−５−イソプロピルヒダントインが特に好ましい。
また、それぞれの使用量としては、ビニル系共重合体中のカルボニル基および／またはアルデヒド基のモル数を（Ｐ）、重合体水分散液に配合される有機ヒドラジン化合物のヒドラジノ基のモル数を（Ｑ）としたとき、その比率｛（Ｐ）／（Ｑ）｝を０．１〜１０の範囲とすることが好ましく、０．８〜２の範囲とすることがより好ましい。これは、｛（Ｐ）／（Ｑ）｝が０．１未満ではカルボニル基またはアルデヒド基と架橋反応を起こさない有機ヒドラジン化合物が大過剰に存在するため耐水性が低下し、｛（Ｐ）／（Ｑ）｝が１０を超えると、架橋度が低いために架橋の効果が得られないためである。
カルボニル基および／またはアルデヒド基含有エチレン性不飽和単量体の使用量は、全重合体中、０．５〜１０質量％、好ましくは１〜８質量％である。その使用量が０．５質量％以上であると、塗膜の耐汚染性、耐候性、耐水性、強度、耐溶剤性および各種下地に対する密着性が向上し、１０質量％以下であると重合安定性や塗膜の柔軟性の低下を抑制できる。なお、２個のヒドラジノ基を有する有機ヒドラジン化合物を配合する場合は、上記（Ｐ）／（Ｑ）を適正にしておくことは当然である。
上記の金属含有ラジカル重合性単量体やカルボニル／ヒドラジン架橋システムを導入することによって、可塑剤を含んでいる軟質下地の可塑剤移行を防止し、耐汚染性を大幅に向上することができるため、このような軟質下地に対して適用することが特に好ましい。
【００２４】
上述した、２０℃における単量体に対する水の溶解度が０．５以下でありホモポリマーのガラス転移温度が２５℃以下である単量体とともに使用する単量体、必要に応じて２種以上を併用することができる。
ビニル系共重合体としてのガラス転移温度は請求項に記載の単量体の使用範囲内であれば特に制約を受けないが、塗膜の非粘着性および耐汚染性の点から、Ｆｏｘの計算式により求められる計算ガラス転移温度（Ｔｇ）が−６０℃以上であることが好ましく、−５０℃以上がより好ましい。また、温冷繰り返し試験や凍結融解試験等での耐クラック性、つまり軟質下地への追従性の点から４０℃以下が好ましく、３０℃以下がより好ましい。ここで、Ｆｏｘの式とは、共重合体のガラス転移温度（℃）についての下記の関係式である。
１／（２７３＋Ｔｇ）＝Σ（Ｗｉ／（２７３＋Ｔｇｉ））
［式中、Ｗｉはモノマーｉの質量分率、ＴｇｉはモノマーｉのホモポリマーのＴｇ（℃）を示す。］
特に、防水シート等の柔軟性の高い素材の保護塗料として使用する場合は、ケイ素を含有する単量体以外の単量体で構成される重合体のガラス転移温度が０℃以下であることが塗膜の下地追従性の点でより好ましい。
【００２５】
重合体水分散液は、各種の単量体を、例えば、溶液重合法、懸濁重合法、乳化重合法の公知の重合法により重合させて得ることができる。特に、乳化重合法によりエマルション形態の重合体水分散液を得ることが、水性被覆材の貯蔵安定性、塗膜の硬度、耐水性、耐候性、耐汚染性等の諸物性の点から好ましい。乳化重合法によりエマルションを得る為には、例えば、界面活性剤の存在下、単量体混合物を重合系内に供給し、水溶性開始剤により重合を行わせる方法、また例えば、有機過酸化物とチオ硫酸ナトリウム等の還元剤を組み合わせたレドックス系開始剤により重合を行わせる方法等の公知の方法を使用することができる。
開始剤としては、例えば、過硫酸カリウム、過硫酸ナトリウム、過硫酸アンモニウム、過酸化水素等の無機過酸化物；過酸化ベンゾイル、ｔ−ブチルハイドロパーオキサイド、ジ−ｔ−ブチルハイドロパーオキサイド、ｔ−ブチルパーオキシベンゾエート、クメンハイドロパーオキサイド等の有機過酸化物；２，２−アゾビスイソブチロニトリル、２，２−アゾビス（２−ジアミノプロパン）ハイドロクロライド、２，２−アゾビス（２，４−ジメチルバレロニトリル）等のアゾ化合物；無機過酸化物と亜硫酸水素ナトリウムまたはロンガリットまたはアスコルビン酸ナトリウムの組み合わせ、有機化酸化物と硫酸水素ナトリウムまたはロンガリットまたはアスコルビン酸ナトリウムの組み合わせ等に代表されるレドックス系触媒；などが挙げられる。
【００２６】
乳化重合法により得たエマルションは、重合後、塩基性化合物の添加により系のｐＨを中性領域〜弱アルカリ性、すなわちｐＨ６．５〜１０．０程度の範囲に調整することで系の安定性を高めることができる。この塩基性化合物としては、例えば、アンモニア、トリエチルアミン、プロピルアミン、ジブチルアミン、アミルアミン、１−アミノオクタン、２−ジメチルアミノエタノール、エチルアミノエタノール、２−ジエチルアミノエタノール、１−アミノ−２−プロパノール、２−アミノ−１−プロパノール、２−アミノ−２−メチル−１−プロパノール、３−アミノ−１−プロパノール、１−ジメチルアミノ−２−プロパノール、３−ジメチルアミノ−１−プロパノール、２−プロピルアミノエタノール、エトキシプロピルアミン、アミノベンジルアルコール、モルホリン、水酸化ナトリウム、水酸化カリウム等が挙げられる。
重合体の分子量を調整する場合には、分子量調整剤として、ｎ−ドデシルメルカプタン、ｔ−ドデシルメルカプタン、α−メチルスチレンダイマー等の公知の連鎖移動剤を用いることで、その調整が可能である。
また、重合体を構成する重合体を１００質量部とするとき、界面活性剤を０．１〜１０質量部添加することが好ましい。界面活性剤が０．１質量部以上存在することによって、ビニル系共重合体水分散液の貯蔵安定性が向上し、界面活性剤存在下に乳化重合する場合には重合時の安定性も向上する。また、界面活性剤を１０質量部以下とすることによって、耐水性を損なうことなく塗料化配合時の安定性、経時的安定性等を維持することができる。より好ましい含有量は、０．５〜８質量部である。
この界面活性剤としては、従来より知られる各種のアニオン性、カチオン性、またはノニオン性の界面活性剤、さらには高分子乳化剤が挙げられる。また、界面活性剤成分中にエチレン性不飽和結合を持つ、いわゆる反応性乳化剤も使用できる。
【００２７】
本発明の水性被覆材は、通常、固形分２０〜８０質量％の範囲で使用される。また、コーティング材料として高度な性能を発現させるために、各種顔料、消泡剤、顔料分散剤、レベリング剤、たれ防止剤、艶消し剤、紫外線吸収剤、酸化防止剤、耐熱性向上剤、スリップ剤、防腐剤、可塑剤等を含んでもよい。さらに、他のエマルション樹脂、水溶性樹脂、粘性制御剤、メラミン類等の硬化剤と混合して使用してもよい。
かくして以上のように配合され、形成された塗料はウレタンゴム系、アクリルゴム系、クロロプレンゴム系、シリコンゴム系、塩化ビニルゴム系、加硫ゴム系、非加硫ゴム系、オレフィン系熱可塑性エラストマー、ポリウレタン樹脂系、ポリアクリル樹脂系、ポリ塩化ビニル樹脂系、軟質ポリエステル樹脂系、軟質エポキシ樹脂系、ポリサルファイド系、ゴムアスファルト等の軟質下地に塗布される。
特に、ＥＰＤＭなどのゴム、ポリ塩化ビニル、ポリエチレン、オレフィン系熱可塑性エラストマー、ウレタンなどからなる予めシートを形成した防水シートやウレタン塗膜などの現場にてシートを形成するような防水シートの保護塗料として好適である。
本発明の水性被覆材を用いて各種材料の表面に被膜を形成する為には、例えば、噴霧コート法、ローラーコート法、バーコート法、エアナイフコート法、刷毛塗り法、ディッピング法等の各種の塗装法を適宜選択して実施すればよい。また、本発明の水性被覆材は、室温乾燥または５０〜１８０℃で加熱乾燥することで、十分に造膜した被膜を得ることができる。
【００２８】
【実施例】
以下、本発明を実施例によりさらに詳細に説明するが、本発明はこれらによって何ら限定されるものではない。なお、以下の記載において「部」は質量基準である。水性被覆材の物性試験については、下記配合組成で塗料を調整し、下記方法に従って試験を実施した。
＜水性被覆材（白エナメル塗料）の作製＞
酸化チタンとしてタイペークＣＲ−９７（石原産業（株）製、塩素法酸化チタン）７０７ｇ、顔料分散剤としてアデカコール Ｗ−１９３（旭電化工業（株）製）１２ｇおよび消泡剤としてサーフィノール ＤＦ−５８（エア・プロダクツ（株）製）２５ｇを脱イオン水２５６ｇと十分に混合し、ガラスビーズを加えて高速分散機で３０分間顔料分散を行い、次いでガラスビーズ等を３００メッシュナイロン紗で濾別し、評価用ミルベースを得た（固形分７１質量％）。
次に、後述する共重合体水分散液１００ｇ（固形分４５質量％基準）に対し、上記の評価用ミルベースを４２．７ｇ、造膜助剤としてキョウワノールＭ（協和発酵（株）社製）を最低造膜温度が０℃となるように適量（ただし、最低造膜温度が既に０℃以下である場合には、キョウワノールＭの添加はなし）、プロピレングリコールを３ｇ、増粘剤としてＲＨＥＯＬＡＴＥ３５０（ＲＨＥＯＸ（株）社製）を０．５ｇ、順に加え、十分に攪拌し、フォードカップ ＃４で３０秒程度になるように脱イオン水を加えて調整した。その後、再度３００メッシュナイロン紗を用いて濾過を行い、評価用水性被覆材（白エナメル塗料）を得た。
【００２９】
＜軟質下地の作製＞
ポリアクリル樹脂系軟質下地を作製するにあたり下記手順にて水性アクリル樹脂を得た。
まず、２−エチルヘキシルアクリレート７０部、ｎ−ブチルメタクリレート１９部、メチルメタクリレート５部、２−ヒドロキシメタクリレート４部、メタクリル酸２部の単量体混合物を１００部、界面活性剤であるアデカリアソープＳＲ−１０を１部および脱イオン水を５０部、十分に混合し、均一な乳化状態のプレエマルション（以下「ＰＥ液」と略す）を作製した。次いで、攪拌機、還流冷却管、温度制御装置、滴下ポンプおよび窒素導入管を備えたフラスコに、脱イオン水を７０部、アデカリアソープＳＲ−１０を０．５部、ＰＥ液を１０部投入し、反応容器の内温を８０℃に昇温した。その後、過硫酸アンモニウム０．１部を脱イオン水１部に溶解したものを投入して１時間保ち、これによりシード粒子を作製した。
さらに、ＰＥ液の残り全部と、過硫酸ナトリウム０．２部を脱イオン水１０部に溶解したものとを、反応容器の内温を８０℃に維持しながら３時間かけて並行滴下した。滴下完了後、内温を８０℃に２時間維持して樹脂への転化率を高め、反応を完結した。その後、６０℃まで冷却し、エマルションのｐＨが８〜１０の間になるように２８％アンモニア水溶液を添加し、３０分間攪拌してポリアクリル樹脂系軟質下地を作製するための水性アクリル樹脂を得た。
次に、この水性アクリル樹脂１００ｇに対し、上記の評価用ミルベースを４２．７ｇ、プロピレングリコールを３ｇ、増粘剤としてＲＨＥＯＬＡＴＥ３５０（ＲＨＥＯＸ（株）社製）を０．５ｇ、順に加え、十分に攪拌し、フォードカップ＃４で３０秒程度になるように脱イオン水を加えて調整した。その後、再度３００メッシュナイロン紗を用いて濾過を行い、ポリアクリル樹脂系軟質下地を作製するための白エナメル塗料を得た。
リン酸亜鉛処理鋼鈑（ボンデライト＃１００処理鋼鈑、板厚０．８ｍｍ、７０ｍｍ×１５０ｍｍ）に、ポリアクリル樹脂系軟質下地を作製するための白エナメル塗料を乾燥膜厚が１００μｍになるようにスプレー塗装し、その後室温で３時間放置し、再度乾燥膜厚が１００μｍになるようにスプレー塗装して、室温で１週間放置したものをポリアクリル樹脂系軟質下地とした。
【００３０】
＜試験板の作製＞
ＥＰＤＭゴムからなる防水シートおよび上記ポリアクリル樹脂系軟質下地に、評価用水性被覆材（白エナメル塗料）を乾燥膜厚が５０μｍになるようにスプレー塗装し、その後室温で３時間放置し、再度乾燥膜厚が５０μｍになるようにスプレー塗装して、室温で１週間放置したものを、下地追従性、耐汚染性、耐候性、耐水性の試験体とした。
【００３１】
＜試験方法＞
（１） 下地追従性
試験体を２０±２℃の水中に１８時間浸漬した後、直ちに−２０±３℃の恒温器中で３時間冷却し、次いで５０±３℃の別の恒温器中で３時間加温し、この２４時間を１サイクルとする操作を実施し、塗膜状態に異常が見られる（塗膜のはがれ、ひび割れ及び膨れ、変色及び光沢低下）までのサイクル数を測定し、以下の基準にて判定した。
「◎」 ：３０サイクルでも異常が見られなかった。
「○」 ：２０〜２９サイクルまでは異常が見られなかった。
「○△」：１０〜１９サイクルまでは異常が見られなかった。
「△」 ：５〜９サイクルまでは異常が見られなかった。
「△×」：１〜４サイクルまでは異常が見られなかった。
「×」 ：１サイクルで異常が見られた。
（２）耐汚染性
試験板を屋外の暴露台（沖縄県糸満市）に南面４５度となるように設置し、２００２年４月〜２００３年３月の１年間暴露したのち、塗膜の暴露前後の白さの差△Ｌを色差計により測定した。△Ｌを汚染性の指標とし、以下の基準で判定した。
「◎」 ：２．５未満。
「○」 ：２．５以上、５．０未満。
「△」 ：５．０以上、７．５未満。
「×」 ：７．５以上
（３）耐候性
試験板を７０ｍｍ×５０ｍｍの大きさに切り取り、ダイプラ・メタルウエザーＫＵ−Ｒ４−Ｗ型（ダイプラ・ウィンテス（株）社製）にこの試験板を入れ、試験サイクル：照射６時間／結露２時間、ＵＶ強度：６５ｍＷ／ｃｍ^２、ブラックパネル温度：照射時６３℃／結露時３０℃、湿度：照射時５０％ＲＨ／結露時９６％ＲＨの条件で、６００時間経過後の６０゜グロスの保持率を耐候性の指標とし、以下の基準で判定した。
「◎」 ：８０％以上。
「○」 ：７０％以上、８０％未満。
「△」 ：６０％以上、７０％未満。
「×」 ：６０％未満。
（４）耐水性
試験板を２０±２℃の水中に１ヶ月間浸した後、室温で２時間乾燥した。塗膜の状態および６０゜グロスの保持率を耐水性の指標とし、以下の基準で判定した。
「◎」 ：割れ・膨れ・剥がれが認められず、光沢保持率が８０％以上。
「○」 ：割れ・膨れ・剥がれが認められず、光沢保持率が７０％以上。
「△」 ：割れ・膨れ・剥がれが認められず、光沢保持率が６０％以上。
「×」 ：どれか１項目でも上記耐水性評価「△」に示される項目を満たさなかったもの。
【００３２】
＜製造例１＞ ケイ素成分の導入方法（イ）で使用するケイ素を含有する重合体の作製方法
環状ジメチルシロキサンオリゴマー３〜７量体混合物９８部と、γ−メタクリロイルオキシプロピルトリメトキシシラン２部、脱イオン水３１０部およびドデシルベンゼンスルホン酸ナトリウム１部からなる組成物を、ホモミキサーで予備混合し、圧力式ホモジナイザーを用いて２００ｋｇ／ｃｍ^２の圧力で強制乳化して、ケイ素原料プレエマルションを得た。
次いで、水９０部およびドデシルベンゼンスルホン酸９部を、攪拌機、還流冷却管、温度制御装置および滴下ポンプを備えたフラスコに仕込み、攪拌下に、フラスコの内温を８５℃に保ちながら、上記ケイ素原料プレエマルションを４時間かけて滴下した。滴下終了後、さらに１時間重合を進行させ、冷却して、ドデシルベンゼンスルホン酸と当モル量の水酸化ナトリウムを加えて、ケイ素を含有する単量体であるポリオルガノシロキサン重合体水分散液（Ａ）を得た。固形分は２０％であった。
【００３３】
＜実施例１及び２（ケイ素成分の導入方法（イ））＞
攪拌機、還流冷却管、温度制御装置、滴下ポンプおよび窒素導入管を備えたフラスコに、製造例１に記載のポリオルガノシロキサン重合体水分散液（Ａ）５部（固形分として１部）、脱イオン水７０部、界面活性剤（反応型アニオン性界面活性剤、旭電化（株）製、商品名アデカリアソープ ＳＲ−１０）０．８部、下記表２に示す初期仕込み組成部のケイ素を含有しない単量体２９部、およびｔ−ブチルハイドロパーオキサイド０．１部を仕込み、室温で１時間、窒素雰囲気下で攪拌した。そして、フラスコの内温を５０℃に昇温した後、硫酸第一鉄０．０００２部、ロンガリット０．０５部、脱イオン水１部の水溶液を添加し、１時間攪拌を継続した。その後、フラスコの内温を８０℃に昇温し、下記表２に示す滴下組成部のケイ素を含有しない単量体７０部、脱イオン水３５部、アデカリアソープ ＳＲ−１０ ２部を予め乳化分散させたＰＥ液と過硫酸アンモニウム５％水溶液２部とを、２時間かけて２系列滴下した。この滴下中はフラスコの内温を８０℃に保持し、滴下が終了してからさらに８０℃で２時間保持し、その後室温まで冷却し、２８％アンモニア水溶液で中和してビニル系共重合体水分散液を得た。
このビニル系共重合体水分散液の固形分および最低造膜温度を下記表２に示す。また、このビニル系共重合体水分散液を用いて水性被覆材（白エナメル塗料）を調製し、下地追従性、耐汚染性、耐候性、耐水性の試験を行った。その結果を下記表５に示す。
【００３４】
＜実施例３（ケイ素成分の導入方法（イ））＞
攪拌機、還流冷却管、温度制御装置、滴下ポンプおよび窒素導入管を備えたフラスコに、製造例１に記載のポリオルガノシロキサン重合体水分散液（Ａ）２５部（固形分として５部）、脱イオン水７０部、下記表２に示す初期仕込み組成部のケイ素を含有しない単量体３５部、およびｔ−ブチルハイドロパーオキサイド０．１部を仕込み、室温で１時間、窒素雰囲気下で攪拌した。そして、フラスコの内温を５０℃に昇温した後、硫酸第一鉄０．０００２部、ロンガリット０．０５部、脱イオン水１部の水溶液を添加し、１時間攪拌を継続した。その後、フラスコの内温を８０℃に昇温し、下記表２に示す滴下組成部のケイ素を含有しない単量体６０部、脱イオン水３０部、アデカリアソープ ＳＲ−１０ １部を予め乳化分散させたＰＥ液と過硫酸アンモニウム５％水溶液２部とを、２時間かけて２系列滴下した。この滴下中はフラスコの内温を８０℃に保持し、滴下が終了してからさらに８０℃で２時間保持し、その後室温まで冷却し、２８％アンモニア水溶液で中和してビニル系共重合体水分散液を得た。
このビニル系共重合体水分散液の固形分および最低造膜温度を下記表２に示す。また、このビニル系共重合体水分散液を用いて水性被覆材（白エナメル塗料）を調製し、下地追従性、耐汚染性、耐候性、耐水性の試験を行った。その結果を下記表５に示す。
【００３５】
＜実施例４（ケイ素成分の導入方法（イ））＞
攪拌機、還流冷却管、温度制御装置、滴下ポンプおよび窒素導入管を備えたフラスコに、製造例１に記載のポリオルガノシロキサン重合体水分散液（Ａ）２５部（固形分として５部）、脱イオン水７０部、下記表２に示す初期仕込み組成部のケイ素を含有しない単量体３５部、およびｔ−ブチルハイドロパーオキサイド０．１部を仕込み、室温で１時間、窒素雰囲気下で攪拌した。そして、フラスコの内温を５０℃に昇温した後、硫酸第一鉄０．０００２部、ロンガリット０．０５部、脱イオン水１部の水溶液を添加し、１時間攪拌を継続した。その後、フラスコの内温を８０℃に昇温し、下記表２に示す滴下組成部のケイ素を含有しない単量体６０部、脱イオン水３０部、アデカリアソープ ＳＲ−１０ ２部を予め乳化分散させたＰＥ液と過硫酸アンモニウム５％水溶液２部とを、２時間かけて２系列滴下した。この滴下中はフラスコの内温を８０℃に保持し、滴下が終了してからさらに８０℃で２時間保持し、その後室温まで冷却し、２−アミノ−２−メチル−１−プロパノール（ＡＭＰ）で中和した。最後に下記表２に示す有機ヒドラジン化合物の２０％水溶液１２．５部を添加してビニル系共重合体水分散液を得た。
このビニル系共重合体水分散液の固形分および最低造膜温度を下記表２に示す。また、このビニル系共重合体水分散液を用いて水性被覆材（白エナメル塗料）を調製し、下地追従性、耐汚染性、耐候性、耐水性の試験を行った。その結果を下記表５に示す。
【００３６】
＜実施例５〜９（ケイ素成分の導入方法（イ））＞
攪拌機、還流冷却管、温度制御装置、滴下ポンプおよび窒素導入管を備えたフラスコに、製造例１に記載のポリオルガノシロキサン重合体水分散液（Ａ）５０部（固形分として１０部）、脱イオン水５０部、下記表２に示す初期仕込み組成部のケイ素を含有しない単量体３０部、およびｔ−ブチルハイドロパーオキサイド０．１部を仕込み、室温で１時間、窒素雰囲気下で攪拌した。そして、フラスコの内温を５０℃に昇温した後、硫酸第一鉄０．０００２部、ロンガリット０．０５部、脱イオン水１部の水溶液を添加し、１時間攪拌を継続した。その後、フラスコの内温を８０℃に昇温し、下記表２に示す滴下組成部のケイ素を含有しない単量体６０部、脱イオン水３０部、アデカリアソープ ＳＲ−１０ １部を予め乳化分散させたＰＥ液と過硫酸アンモニウム５％水溶液２部とを、２時間かけて２系列滴下した。この滴下中はフラスコの内温を８０℃に保持し、滴下が終了してからさらに８０℃で２時間保持し、その後室温まで冷却し、２８％アンモニア水溶液で中和してビニル系共重合体水分散液を得た。
このビニル系共重合体水分散液の固形分および最低造膜温度を下記表２に示す。また、このビニル系共重合体水分散液を用いて水性被覆材（白エナメル塗料）を調製し、下地追従性、耐汚染性、耐候性、耐水性の試験を行った。その結果を下記表５に示す。
【００３７】
＜実施例１０（ケイ素成分の導入方法（イ））＞
攪拌機、還流冷却管、温度制御装置、滴下ポンプおよび窒素導入管を備えたフラスコに、製造例１に記載のポリオルガノシロキサン重合体水分散液（Ａ）５０部（固形分として１０部）、脱イオン水５０部、下記表２に示す初期仕込み組成部のケイ素を含有しない単量体３０部、およびｔ−ブチルハイドロパーオキサイド０．１部を仕込み、室温で１時間、窒素雰囲気下で攪拌した。そして、フラスコの内温を５０℃に昇温した後、硫酸第一鉄０．０００２部、ロンガリット０．０５部、脱イオン水１部の水溶液を添加し、１時間攪拌を継続した。その後、フラスコの内温を８０℃に昇温し、下記表２に示す滴下組成部のケイ素を含有しない単量体６０部、脱イオン水３０部、アデカリアソープ ＳＲ−１０ ２部を予め乳化分散させたＰＥ液と過硫酸アンモニウム５％水溶液２部とを、２時間かけて２系列滴下した。この滴下中はフラスコの内温を８０℃に保持し、滴下が終了してからさらに８０℃で２時間保持し、その後室温まで冷却し、ＡＭＰで中和した。最後に下記表２に示す有機ヒドラジン化合物の２０％水溶液１２．５部を添加してビニル系共重合体水分散液を得た。
このビニル系共重合体水分散液の固形分および最低造膜温度を下記表３に示す。また、このビニル系共重合体水分散液を用いて水性被覆材（白エナメル塗料）を調製し、下地追従性、耐汚染性、耐候性、耐水性の試験を行った。その結果を下記表５に示す。
【００３８】
＜実施例１１（ケイ素成分の導入方法（イ））＞
攪拌機、還流冷却管、温度制御装置、滴下ポンプおよび窒素導入管を備えたフラスコに、製造例１に記載のポリオルガノシロキサン重合体水分散液（Ａ）１２５部（固形分として２５部）、下記表２に示す初期仕込み組成部のケイ素を含有しない単量体２５部、およびｔ−ブチルハイドロパーオキサイド０．１部を仕込み、室温で１時間、窒素雰囲気下で攪拌した。そして、フラスコの内温を５０℃に昇温した後、硫酸第一鉄０．０００２部、ロンガリット０．０５部、脱イオン水１部の水溶液を添加し、１時間攪拌を継続した。その後、フラスコの内温を８０℃に昇温し、下記表２に示す滴下組成部のケイ素を含有しない単量体５０部、脱イオン水２５部、アデカリアソープ ＳＲ−１０ ０．５部を予め乳化分散させたＰＥ液と過硫酸アンモニウム５％水溶液２部とを、２時間かけて２系列滴下した。この滴下中はフラスコの内温を８０℃に保持し、滴下が終了してからさらに８０℃で２時間保持し、その後室温まで冷却し、２８％アンモニア水溶液で中和してビニル系共重合体水分散液を得た。
このビニル系共重合体水分散液の固形分および最低造膜温度を下記表３に示す。また、このビニル系共重合体水分散液を用いて水性被覆材（白エナメル塗料）を調製し、下地追従性、耐汚染性、耐候性、耐水性の試験を行った。その結果を下記表５に示す。
【００３９】
＜実施例１２（ケイ素成分の導入方法（イ））＞
攪拌機、還流冷却管、温度制御装置、滴下ポンプおよび窒素導入管を備えたフラスコに、製造例１に記載のポリオルガノシロキサン重合体水分散液（Ａ）２００部（固形分として４０部）、下記表２に示す初期仕込み組成部のケイ素を含有しない単量体２５部、およびｔ−ブチルハイドロパーオキサイド０．１部を仕込み、室温で１時間、窒素雰囲気下で攪拌した。そして、フラスコの内温を５０℃に昇温した後、硫酸第一鉄０．０００２部、ロンガリット０．０５部、脱イオン水１部の水溶液を添加し、１時間攪拌を継続した。その後、フラスコの内温を８０℃に昇温し、下記表２に示す滴下組成部のケイ素を含有しない単量体３５部、脱イオン水１８部、アデカリアソープ ＳＲ−１０ ０．５部を予め乳化分散させたＰＥ液と過硫酸アンモニウム５％水溶液２部とを、２時間かけて２系列滴下した。この滴下中はフラスコの内温を８０℃に保持し、滴下が終了してからさらに８０℃で２時間保持し、その後室温まで冷却し、２８％アンモニア水溶液で中和してビニル系共重合体水分散液を得た。
このビニル系共重合体水分散液の固形分および最低造膜温度を下記表３に示す。また、このビニル系共重合体水分散液を用いて水性被覆材（白エナメル塗料）を調製し、下地追従性、耐汚染性、耐候性、耐水性の試験を行った。その結果を下記表５に示す。
【００４０】
＜実施例１３及び１４（ケイ素成分の導入方法（ロ））＞
攪拌機、還流冷却管、温度制御装置、滴下ポンプおよび窒素導入管を備えたフラスコに、脱イオン水６０部、下記表２に示す初期仕込み組成部のケイ素を含有しない単量体３５部、アデカリアソープＳＲ−１０ １部を仕込み、室温で１時間、窒素雰囲気下で攪拌した。そして、フラスコの内温を８０℃に昇温した後、過硫酸アンモニウム５％水溶液１０部を添加し、１時間攪拌を継続した。その後、フラスコの温度を６０℃に下げた。
次に、脱イオン水３５部、下記表２に示す滴下組成部のケイ素を含有する単量体５部及びケイ素を含有しない単量体６５部、アデカリアソープＳＲ−１０ ２部を予め乳化分散させたＰＥ液と過硫酸アンモニウム５％水溶液２部、亜硫酸水素ナトリウム５％水溶液１部とを、２時間かけて３系列滴下した。この滴下中はフラスコの内温を６０℃に保持し、滴下が終了してからさらに６０℃で２時間保持し、その後室温まで冷却し、２８％アンモニア水溶液で中和してビニル系共重合体水分散液を得た。
このビニル系共重合体水分散液の固形分および最低造膜温度を下記表３に示す。また、このビニル系共重合体水分散液を用いて水性被覆材（白エナメル塗料）を調製し、下地追従性、耐汚染性、耐候性、耐水性の試験を行った。その結果を下記表５に示す。
【００４１】
＜実施例１５（ケイ素成分の導入方法（ハ））＞
攪拌機、還流冷却管、温度制御装置、滴下ポンプおよび窒素導入管を備えたフラスコに、脱イオン水６０部、下記表２に示す初期仕込み組成部のケイ素を含有しない単量体３５部、アデカリアソープＳＲ−１０ １部を仕込み、室温で１時間、窒素雰囲気下で攪拌した。そして、フラスコの内温を８０℃に昇温した後、過硫酸アンモニウム５％水溶液１０部を添加し、１時間攪拌を継続した。
次に、脱イオン水３５部、下記表２に示す滴下組成部のケイ素を含有する単量体５部及びケイ素を含有しない単量体６５部、アデカリアソープＳＲ−１０ ２部をホモミキサーで１００００ｒｐｍの攪拌速度で１０分間攪拌して、ＰＥ液を作製した。このＰＥ液と過硫酸アンモニウム５％水溶液２部とを、２時間かけて２系列滴下した。この滴下中はフラスコの内温を８０℃に保持し、滴下が終了してからさらに８０℃で２時間保持し、その後室温まで冷却し、２８％アンモニア水溶液で中和してビニル系共重合体水分散液を得た。
このビニル系共重合体水分散液の固形分および最低造膜温度を下記表３に示す。また、このビニル系共重合体水分散液を用いて水性被覆材（白エナメル塗料）を調製し、下地追従性、耐汚染性、耐候性、耐水性の試験を行った。その結果を下記表５に示す。
【００４２】
＜比較例１及び２（アクリルエマルション）＞
まず、下記表４に示す滴下組成部のケイ素を含有しない単量体１００部、アデカリアソープＳＲ−１０ ２部および脱イオン水５０部を十分に混合し、ＰＥ液を作製した。
次いで、攪拌機、還流冷却管、温度制御装置、滴下ポンプおよび窒素導入管を備えたフラスコに、脱イオン水７０部、アデカリアソープＳＲ−１０ ０．５部を投入し、反応容器の内温を８０℃に昇温した。
その後、予め乳化したＰＥ液と過硫酸アンモニウム５％水溶液５部とを、３時間かけて２系列滴下した。この滴下中はフラスコの内温を８０℃に保持し、滴下が終了してからさらに８０℃で２時間保持し、その後室温まで冷却し、２８％アンモニア水溶液で中和してビニル系共重合体水分散液を得た。
このビニル系共重合体水分散液の固形分および最低造膜温度を下記表４に示す。また、このビニル系共重合体水分散液を用いて水性被覆材（白エナメル塗料）を調製し、下地追従性、耐汚染性、耐候性、耐水性の試験を行った。その結果を下記表５に示す。
【００４３】
【表２】

【００４４】
【表３】

【００４５】
【表４】

【００４６】
【表５】

【００４７】
表２〜表４中の略号は、以下の化合物を示す。
・「ｎ−ＢＭＡ」：ｎ−ブチルメタクリレート
・「ｎ−ＢＡ」：ｎ−ブチルアクリレート
・「２−ＥＨＡ」：２−エチルヘキシルアクリレート
・「ｔ−ＢＭＡ」：ｔ−ブチルメタクリレート
・「ＣＨＭＡ」：シクロヘキシルメタクリレート
・「ＭＡＡ」：メタクリル酸
・「２−ＨＥＭＡ」：２−ヒドロキシエチルメタクリレート
・「ブレンマー７０ＰＥＰ３５０Ｂ」：ヒドロキシ（ポリエチレングリコール−ポリプロピレングリコール）モノメタクリレート（商品名、日本油脂（株）社製）
・「アデカスタブＬＡ−８２」：１，２，２，６，６−ペンタメチル−４−ピペリジルメタクリレート（商品名、旭電化工業（株）社製）
・「ＤＡＡｍ」：ダイアセトンアクリルアミド
・「ＭＭＡ」：メチルメタクリレート
・「ＥＡ」：エチルアクリレート
・「アデカリアソープＳＲ−１０」：反応型アニオン性界面活性剤（商品名、旭電化（株）社製）
・「ＤＢＳＮａ」：ドデシルベンゼンスルホン酸ナトリウム
・「ＦＭ０７２５」：シリコーンマクロモノマー、分子量１００００（商品名、チッソ（株）社製）
・「ＶＤＨ」：１，３−ビス（ヒドラジノカルボエチル）−５−イソプロピルヒダントイン（商品名アミキュアＶＤＨ、味の素ファインテクノ（株）社製）
・「ＡＭＰ」：２−アミノ−２−メチル−１−プロパノール
【００４８】
【発明の効果】
以上説明したように、本発明によれば、ケイ素を含有する単量体単位（Ａ）と２０℃における単量体に対する水の溶解度が０．５以下であって、ホモポリマーのガラス転移温度が２５℃以下であるケイ素を含有しない単量体に由来する単量体単位（Ｂ）とを含む重合体を含有することにより、優れた軟質下地対する追従性および耐汚染性、耐候性、耐水性をも兼ね備えた水性被覆材を提供できる。
本発明の水性低汚染被覆材は工業上極めて有用なものであり、具体的には、例えば、ウレタンゴム系、アクリルゴム系、クロロプレンゴム系、シリコンゴム系、塩化ビニルゴム系、加硫ゴム系、非加硫ゴム系、オレフィン系熱可塑性エラストマー、ポリウレタン樹脂系、ポリアクリル樹脂系、ポリ塩化ビニル樹脂系、軟質ポリエステル樹脂系、軟質エポキシ樹脂系、ポリサルファイド系、ゴムアスファルト等の各種軟質下地の表面仕上げ等に使用することができ、主に建築物、土木構造物等の躯体保護に使用する水性被覆材として極めて有用である。[0001]
BACKGROUND OF THE INVENTION
The present invention includes urethane rubber, acrylic rubber, chloroprene rubber, silicon rubber, vinyl chloride rubber, vulcanized rubber, non-vulcanized rubber, olefin thermoplastic elastomer, polyurethane resin, polyacrylic resin, The present invention relates to a coating material used for a protective coating for a soft base such as a polyvinyl chloride resin type, a soft polyester resin type, a soft epoxy resin type, a polysulfide type, or a rubber asphalt.
[0002]
[Prior art]
In recent years, in the field of paints used for buildings and civil engineering structures, water-based paints that use water as a solvent, from solvent-based paints that use organic solvents as solvents, in consideration of the health and environmental protection of painters and local residents. Conversion to is planned. In order to meet the user's need to protect the aesthetics of buildings for a long period of time, paints having both weather resistance and contamination resistance have been developed. Furthermore, there is a problem that the coating film cracks due to a temperature difference between summer / winter, daytime / nighttime, etc., and there is an increasing need for a coating film with high base followability. In particular, urethane rubber, acrylic rubber, chloroprene rubber, silicon rubber, vinyl chloride rubber, vulcanized rubber, non-vulcanized rubber, olefin thermoplastic elastomer, polyurethane resin, polyacrylic resin, polychlorinated In protective coatings for soft bases such as vinyl resin, soft polyester resin, soft epoxy resin, polysulfide, rubber asphalt, etc., it is important that the coating has good base followability, that is, flexibility and adhesion. is there.
As such a protective coating, for example, an acrylic coating aqueous dispersion using a polymer having a glass transition temperature of 0 ° C. or higher has been reported. (For example, Patent Document 1)
[Patent Document 1] Japanese Patent No. 3094118
[0003]
[Problems to be solved by the invention]
A protective material using such an aqueous dispersion has excellent adhesion to a substrate, particularly a plastic substrate, and can form a coating film with excellent antifouling properties and hardness, but it can follow a soft substrate. And it is not satisfactory in terms of weather resistance. In addition, because the flexibility, stain resistance, weather resistance, and water resistance of the coating film are contradictory, the conventional water-based paint has the following ability to the soft base of the coating film, stain resistance, weather resistance, and water resistance. It was difficult to achieve a high balance.
The present invention has been made in order to solve these problems, and it is a soft base protecting aqueous solution that forms a coating film in which the followability to a soft base, stain resistance, weather resistance, and water resistance are highly balanced. The object is to provide a covering material.
[0004]
[Means for Solving the Problems]
The gist of the present invention is that the monomer unit (A) containing silicon,
A monomer unit (B) derived from a silicon-free monomer having a water solubility in a monomer at 20 ° C. of 0.5 or less and a glass transition temperature of the homopolymer of 25 ° C. or less; It is in the aqueous | water-based coating material for soft base protection containing the polymer to contain.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
The aqueous coating agent for protecting a soft base of the present invention has a monomer unit (A) containing silicon and water solubility in the monomer at 20 ° C. of 0.5 or less, and the glass transition temperature of the homopolymer. And a polymer containing a monomer unit (B) derived from a monomer containing no silicon and having a temperature of 25 ° C. or lower.
By containing the monomer unit containing silicon, the stain resistance, weather resistance, and water resistance of the coating film can be improved.
Further, in the polymer constituting the aqueous coating material, a monomer unit containing no silicon having a water solubility in a monomer at 20 ° C. of 0.5 or less and a glass transition temperature of the homopolymer of 25 ° C. or less. It is preferable to contain within the range of 50-99 mass%.
[0006]
The method for synthesizing the polymer is not particularly limited, and examples thereof include the following methods (a) to (c). Moreover, it is also possible to implement combining 2 or more of method (A)-(C) as needed.
(A) Silicon in which the solubility of water in the monomer at 20 ° C. is 0.5 or less and the glass transition temperature of the homopolymer is 25 ° C. or less in the presence of polysiloxane particles dispersed in an aqueous medium. A method of obtaining a polymer aqueous dispersion by polymerizing a monomer not containing benzene or a mixture of this with another monomer.
(B) The solubility of water in the monomer at 20 ° C. is 0.5 or less and the homopolymer has a glass transition temperature of 25 ° C. or less, a silicon-free monomer, hydrolyzable silane, and A method in which a polymer aqueous dispersion is obtained by radical polymerization of other monomers in the presence of water, a surfactant and a polymerization initiator.
(C) The solubility of water in the monomer at 20 ° C. is 0.5 or less, and the homopolymer has a glass transition temperature of 25 ° C. or less. A method of obtaining a polymer aqueous dispersion by radical polymerization with other monomers in the presence of water, a surfactant and a polymerization initiator.
[0007]
Hereinafter, the above-described methods (a) to (c) will be sequentially described.
In the method (a), in the presence of polysiloxane particles dispersed in an aqueous medium, the solubility of water in the monomer at 20 ° C. is 0.5 or less, and the glass transition temperature of the homopolymer is 25 ° C. or less. This is a method of polymerizing a silicon-free monomer or a mixture of this with another monomer to obtain a polymer aqueous dispersion.
Preferably, by using a silicon-containing graft crossing agent, the polymer block (I) having an organosiloxane as a repeating unit, the solubility of water in a monomer at 20 ° C. is 0.5 or less, and a homopolymer glass Polymer block (II) containing a monomer unit not containing silicon having a transition temperature of 25 ° C. or lower, a silicon-containing graft cross-linking agent (III) copolymerized with polymer block (I) and polymer block (II) A graft block copolymer aqueous dispersion composed of
The polymer block (I) constituting the graft block copolymer is composed of dimethyldialkoxysilanes such as dimethyldimethoxysilane and dimethyldiethoxysilane, hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane. , Dimethylsiloxane cyclic oligomers such as dodecamethylcyclohexasiloxane, tetradecamethylcycloheptasiloxane, dimethyl cyclic (dimethylsiloxane cyclic oligomer 3-7 mer mixture), dimethyldichlorosilane, etc. can be synthesized as raw materials. . Among them, the dimethylsiloxane cyclic oligomer is most suitable as a raw material for the polymer block (I) because there is no alcohol byproduct.
The polymer block (I) is preferably contained in the range of 0.5 to 50% by mass in the graft block copolymer. If content of polymer block (I) is 0.5 mass% or more, the softness | flexibility of a coating film, a weather resistance, and water resistance will improve. Moreover, if it is 50 mass% or less, the fall of the hardness of a coating film, intensity | strength, and stain resistance can be suppressed. A more preferable content is 1 to 40% by mass.
The reason why it is possible to balance the flexibility, weather resistance and water resistance of the coating film by using the polymer block (I) in the range of 0.5 to 50% by mass is, for example, dimethylsiloxane cyclic oligomer The glass transition temperature of the dimethylsiloxane polymer which is a condensate of -123 ° C., the solubility of water in the monomer at 20 ° C. exemplified later in Table 1 is 0.5 or less, and the glass transition temperature of the homopolymer is This is because the glass transition temperature is lower than that of a monomer not containing silicon at 25 ° C. or lower, so that the flexibility is further improved, and since the silicon component is included, the weather resistance and water resistance are further improved.
[0008]
In the polymer block (II) constituting the graft block copolymer, the solubility of water in the monomer at 20 ° C. described later is 0.5 or less, and the glass transition temperature of the homopolymer is 25 ° C. or less. A monomer not containing silicon or a mixture of this with another monomer is used.
The silicon-containing graft crossing agent (III) constituting the graft block copolymer is a component that ensures the transparency of the resulting coating film. Examples of the silicon-containing graft crossing agent (III) include compounds containing one or more hydrolyzable silyl groups and one or more vinyl polymerizable functional groups or mercapto groups in the molecule. The hydrolyzable silyl group is preferably an alkoxysilyl group in view of polymerization reactivity and ease of handling.
Specific examples of the silicon-containing graft cross-linking agent (III) include vinyl silanes such as vinylmethyldimethoxysilane, vinyltrimethoxysilane, and vinyltriethoxysilane; γ-methacryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropylmethyldimethoxy. Methacryloyloxyalkylsilanes such as silane and γ-methacryloyloxypropyltriethoxysilane; acryloyloxyalkylsilanes such as γ-acryloyloxypropyltrimethoxysilane, γ-acryloyloxypropylmethyldimethoxysilane, and γ-acryloyloxypropyltriethoxysilane Γ-mercaptopropyltrimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropylmethyldiethoxy Mercaptoalkyl silanes such as silane; and the like. Among these, methacryloyloxyalkylsilanes, acryloyloxyalkylsilanes, and mercaptoalkylsilanes are particularly preferable in consideration of vinyl polymerization reactivity. These may be used alone or in combination of two or more as required.
The silicon-containing graft crossing agent (III) is preferably used within a range of 0.5 to 50 mol% based on 100 mol% of the total silicon atoms in the graft block copolymer. If this content is 0.5 mol% or more, the transparency of the coating film tends to be improved, and if it is 50 mol% or less, the coating film performance tends to be improved. A more preferable content is 1 to 15 mol%. When the content is 1 mol% or more, the transparency of the resulting coating film is extremely good, and when it is 15 mol% or less, the latex stability during emulsion polymerization is good.
[0009]
Method (b) includes a silicon-free monomer, hydrolyzable silane, wherein the solubility of water in the monomer at 20 ° C. is 0.5 or less and the glass transition temperature of the homopolymer is 25 ° C. or less. This is a method for obtaining a polymer aqueous dispersion by radical polymerization of other monomers as necessary in the presence of water, a surfactant and a polymerization initiator.
The hydrolyzable silane used here is not particularly limited as long as it hydrolyzes and condenses with an acid catalyst or an alkali catalyst to form an organopolysiloxane. Specific examples of the hydrolyzable silane include the following general formula (1)
(R ¹ ) _n -Si- (R ² ) _4-n (1)
(Wherein R ¹ Represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 16 carbon atoms, an aryl group or a cycloalkyl group; ² Represents an alkoxy group having 1 to 8 carbon atoms, an acetoxy group or a hydroxyl group, and n represents an integer of 1 to 3. )
And organoalkoxysilanes represented by the formula:
In the general formula (1), R ¹ If there are 2 or 3, R ¹ May all be the same group, or a part or all of them may be different groups. R ¹ As such, a methyl group and a phenyl group are particularly preferable. R ² As such, a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a methoxyethoxy group, and a hydroxyl group are particularly preferable.
Examples of the organoalkoxysilanes represented by the general formula (1) include methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, and diphenyl. Particularly preferred are diethoxysilane, isobutyltrimethoxysilane, methylphenyldimethoxysilane and the like.
Moreover, as alkoxysilanes other than general formula (1), it is possible to copolymerize with an ethylenically unsaturated monomer, for example, vinyltris (β-methoxyethoxy) silane, vinyltrimethoxysilane, vinyltriethoxysilane, γ- (Meth) acryloyloxypropyltrimethoxysilane, γ- (meth) acryloyloxypropyltriethoxysilane, γ- (meth) acryloyloxypropyldimethoxymethylsilane, γ-glycidoxypropyltrimethoxysilane, N-β- (amino Ethyl) γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, tetramethoxysilane, tetraethoxysilane and the like can also be used.
Also, for example, chlorosilanes such as methyldichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, phenyltrichlorosilane, diphenylchlorosilane, vinylchlorosilane, γ- (meth) acryloyloxypropyltrichlorosilane, γ- (meth) acryloyloxypropyldichloromethylsilane Cyclic silanes such as octamethylcyclotetrasilane, octaphenylcyclosiloxane, hexamethylcyclotrisiloxane, decamethylcyclopentasiloxane, tetramethyltetravinylcyclotetrasiloxane; and the like can also be used.
These hydrolyzable silanes can be used alone or in combination of two or more as required. Further, it is particularly preferable to use a hydrolyzable silane copolymerizable with the ethylenically unsaturated monomer and another hydrolyzable silane.
The amount of the hydrolyzable silane used is preferably 0.5 to 10% by mass in the polymer. If the amount used is 0.5% by mass or more, the effect of improving the stain resistance and weather resistance due to the use of hydrolyzable silane as a constituent component tends to be exhibited. Moreover, if it is 10 mass% or less, the softness | flexibility of a coating film, the fall of water resistance, the storage stability of a vinyl-type copolymer aqueous dispersion, and the fall of pigment dispersion stability can be suppressed. A more preferable content is 1 to 8% by mass.
A silicon-free monomer for use with a hydrolyzable silane having a water solubility in the monomer at 20 ° C. of 0.5 or less and a homopolymer glass transition temperature of 25 ° C. or less, and The other monomers used depending on the use are those described below.
As a polymerization method, the solubility of water in the monomer at 20 ° C. is 0.5 or less and the homopolymer has a glass transition temperature of 25 ° C. or less, a silicon-free monomer, hydrolyzable silane, and If necessary, other monomers may be polymerized in a dispersion system based on water, a surfactant, a polymerization initiator, an acid catalyst for hydrolysis and condensation of hydrolyzable silane, and polymer particles. Is preferred. In this emulsion polymerization, the monomer or monomer mixture and the hydrolyzable silane may be polymerized simultaneously in the same reaction system, or one of them may be polymerized first. It is preferable to polymerize simultaneously.
Examples of the acid catalyst for hydrolysis and condensation of hydrolyzable silane include inorganic acids such as hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, methanesulfonic acid, p-toluenesulfonic acid, β-naphthalenesulfonic acid, 2- Organic sulfonic acids such as mesitylenesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, and alkylbenzenesulfonic acid, and fatty acids such as formic acid, acetic acid, maleic acid, fumaric acid, and (meth) acrylic acid can be used. However, it is not limited to these. The amount of use is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 5 parts by mass with respect to 100 parts by mass of the solid content of the vinyl copolymer aqueous dispersion.
After completion of emulsion polymerization, as a curing catalyst during film formation, for example, dibutyltin dilaurate, dioctyltin dilaurate, dibutyltin diacetate, tin octylate, tin laurate, tin octylate, lead octylate, tetrabutyl titanate, etc. An acid metal salt can be added to the vinyl copolymer aqueous dispersion. The amount used is preferably 0.0001 to 10 parts by mass, and more preferably 0.01 to 5 parts by mass with respect to 100 parts by mass of the solid content of the vinyl copolymer aqueous dispersion. The curing catalyst is desirably emulsified with a surfactant and water when used.
[0010]
Method (c) includes a silicon-free monomer, a silicone macromonomer, and a necessary component in which the solubility of water in the monomer at 20 ° C. is 0.5 or less and the glass transition temperature of the homopolymer is 25 ° C. or less. In accordance with the method, radical polymerization is carried out with other monomers in the presence of water, a surfactant and a polymerization initiator to obtain a polymer aqueous dispersion. The silicone macromonomer used here is a terminal Is a high molecular weight monomer having a radical polymerizable group and having a polysiloxane structure. The molecular weight is preferably about 1000 to 10,000. The polymerizable group at the terminal of the silicone macromonomer is preferably an acryl group or a methacryl group from the viewpoint of ease of copolymerization with the ethylenically unsaturated monomer.
Silicone macromonomer is available as a commercial item, for example. Specific examples thereof include FM0711, FM0721, FM0725 manufactured by Chisso Corporation, AK-5, AK-30, AK-32 manufactured by Toa Gosei Co., Ltd., and X-manufactured by Shin-Etsu Chemical Co., Ltd. 22-174DX, etc. (all are trade names). These may be used alone or in combination of two or more as required.
The amount of the silicone macromonomer used is preferably 0.5 to 10% by mass in the polymer. If the amount used is 0.5% by mass or more, the effect of improving weather resistance and water resistance due to the silicone macromonomer as a constituent component tends to be exhibited. Moreover, if it is 10 mass% or less, the phenomenon that an unreacted macromonomer remains or the polymer component rich in a silicon component will separate from the vinyl copolymer aqueous dispersion can be suppressed. Such a phenomenon not only deteriorates the polymerization stability of the vinyl copolymer aqueous dispersion, but also the coating film formed with the paint produced using the vinyl copolymer aqueous dispersion is uneven. As a result, the adhesive layer formed by the unreacted macromonomer may cause contamination, or the portion having too much silicon component will not produce a robust coating film, resulting in a coating film with excellent weather resistance and water resistance. There is a tendency to cause the problem of being unable to. A more preferable content is 1 to 8% by mass.
Non-silicon-containing monomer having water solubility in monomer at 20 ° C. used with silicone macromonomer of 0.5 or less and glass transition temperature of homopolymer of 25 ° C. or less, other monomer Uses the following.
[0011]
Among the methods (a) to (c) described above, when the silicon component is introduced by the method (a), the flexibility and adhesion of the coating is improved, so that the followability to the soft base is improved, and the stain resistance and weather resistance are improved. The water resistance can be achieved in the most balanced manner.
[0012]
As the polymer used in the present invention, a silicon-free monomer having a water solubility in a monomer at 20 ° C. of 0.5 or less and a homopolymer glass transition temperature of 25 ° C. or less is used.
Such monomers include n-butyl (meth) acrylate, n-amyl (meth) acrylate, i-amyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n -Octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, lauryl (meth) acrylate, etc. are mentioned.
Among these, use of n-butyl (meth) acrylate or 2-ethylhexyl (meth) acrylate is preferred because it tends to be compatible with the flexibility, weather resistance, water resistance and stain resistance of the coating film.
For some of these monomers, the solubility of water in the monomer at 20 ° C. and the glass transition temperature of the homopolymer are shown in Table 1 below.
[0013]
[Table 1]

[0014]
Examples of other monomers used in the present invention include alkyl (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, i-butyl methacrylate, sec-butyl methacrylate, and t-butyl methacrylate. Cycloalkyl methacrylates such as cyclohexyl methacrylate; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, Hydroxyalkyl (meth) acrylates such as glycerol mono (meth) acrylate; hydroxypolyethylene oxide mono (meth) acrylate, hydroxypolypropylene oxide mono (meth) acrylate, Roxy (polyethylene oxide-polypropylene oxide) mono (meth) acrylate, hydroxy poly (ethylene oxide / propylene oxide) mono (meth) acrylate, hydroxy (polyethylene oxide-polytetramethylene oxide) mono (meth) acrylate, hydroxy poly (ethylene oxide / tetra) Methylene oxide) mono (meth) acrylate, hydroxy (polypropylene oxide-polytetramethylene oxide) mono (meth) acrylate, hydroxy poly (propylene oxide / tetramethylene oxide) mono (meth) acrylate, methoxypolyethylene oxide mono (meth) acrylate, Lauroxy polyethylene oxide mono (meth) acrylate, stearoxy polyethylene oxide mono (meth) a Relate, allyloxypolyethylene oxide mono (meth) acrylate, nonylphenoxypolyethylene oxide mono (meth) acrylate, nonylphenoxypolypropyleneoxide mono (meth) acrylate, octoxy (polyethyleneoxide-polypropyleneoxide) mono (meth) acrylate, nonylphenoxypoly ( (Ethylene oxide / propylene oxide) poly (alkylene oxide) -containing (meth) acrylates such as mono (meth) acrylate; hydroxycycloalkyl (meth) acrylates such as p-hydroxycyclohexyl (meth) acrylate; lactone-modified hydroxyalkyl (meth) acrylate 2-aminoethyl (meth) acrylate, 2-dimethylaminoethyl (meth) acrylate, 2-aminopropyl Aminoalkyl (meth) acrylates such as propyl (meth) acrylate and 2-butylaminoethyl (meth) acrylate; amide group-containing polymerizability such as (meth) acrylamide, N-methylolacrylamide and N-butoxymethyl (meth) acrylamide Monomer; Multifunctional (meth) acrylates such as ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate; 2- ( 2′-hydroxy-5 ′-(meth) acryloxyethylphenyl) -2H-benzotriazole, 1- (meth) acryloyl-4-hydroxy-2,2,6,6-tetramethylpiperidine, 1- (meta ) Acrylyl-4-methoxy-2, , 6,6-tetramethylpiperidine, 1- (meth) acryloyl-4-amino-4-cyano-2,2,6,6-tetramethylpiperidine and the like (meth) acrylate having anti-ultraviolet groups; di (meth) Metal-containing radical polymerizable monomers such as zinc acrylate; dimethylaminoethyl (meth) acrylate methyl chloride salt, glycidyl (meth) acrylate, (meth) acrylonitrile, phenyl (meth) acrylate, isobornyl (meth) acrylate, tetrahydrofur Other (meth) acrylic monomers such as furyl (meth) acrylate, methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate; acrolein, diacetone acrylamide, formylstyrene, vinyl methyl ketone, vinyl ethyl ketone, vinyl isobuty Carbonyl group-containing monomers based on aldehyde groups or keto groups such as luketone, pivalin aldehyde, diacetone (meth) acrylate, acetonyl acrylate, acetoacetoxyethyl (meth) acrylate; styrene, methylstyrene, chlorostyrene, methoxystyrene, etc. Aromatic vinyl monomers; conjugated diene monomers such as 1,3-butadiene, isoprene, 2-chloro-1,3-butadiene; (meth) acrylic acid, itaconic acid, fumaric acid, maleic acid, Carboxyl group-containing monomers such as 2- (meth) acryloxyethyl phthalic acid and 2- (meth) acryloxyethyl hexahydrophthalic acid; vinyl acetate, vinyl chloride, ethylene, vinyl propionate, etc. However, these are limited to those that can be radically polymerized. Not intended to be.
Of the above monomers, it is particularly preferable to use a combination of t-butyl methacrylate and cyclohexyl methacrylate. This content is preferably in the range of 2 to 49% by mass in the entire polymer. When this content is 2% by mass or more, the water resistance and weather resistance of the coating film are improved, and when it is 49% by mass or less, a decrease in flexibility of the coating film can be suppressed. A more preferable content is 5 to 40% by mass.
[0015]
In the present invention, the solubility of water in the monomer at 20 ° C. of the monomer is 0.5 or less, so that the weather resistance and water resistance of the coating film are improved, and the glass transition temperature of the homopolymer is 25 ° C. or less. As a result, the flexibility of the coating film is improved.
By containing a monomer unit satisfying these two conditions within the range of 50 to 99% by mass in the total polymer, the flexibility, weather resistance, and water resistance of the coating film can be improved.
When the content is 50% by mass or more, the flexibility of the coating film is improved, and when it is 99% by mass or less, deterioration of the stain resistance, weather resistance, and water resistance of the coating film can be suppressed. A more preferable content is 55 to 90% by mass.
In particular, the use of a monomer having a homopolymer glass transition temperature of 0 ° C. or lower further improves the flexibility of the coating film. It is preferable that the content is 35-90 mass% in all the polymers. A more preferable content is 40 to 80 parts by mass.
[0016]
In the present invention, an ethylenically unsaturated carboxylic acid monomer is used as another monomer from the viewpoint of the storage stability of the polymer aqueous dispersion and the blending stability when a pigment or additive is added to form a paint. It is preferable to contain. This content is preferably in the range of 0.1 to 10% by mass in the total polymer. When the content is 0.1% by mass or more, the storage stability of the vinyl copolymer aqueous dispersion is improved, and aggregates are generated when the aqueous coating material of the present invention is colored with a pigment. Problems can be avoided. Moreover, the fall of the water resistance of a coating film and a weather resistance can be suppressed as this content is 10 mass% or less. A more preferable content is 0.5 to 8% by mass.
Examples of the ethylenically unsaturated carboxylic acid monomer include (meth) acrylic acid, itaconic acid, citraconic acid, maleic acid, monomethyl maleate, monobutyl maleate, monomethyl itaconate, monobutyl itaconate, vinylbenzoic acid, Oxalic acid monohydroxyethyl (meth) acrylate, tetrahydrophthalic acid monohydroxyethyl (meth) acrylate, tetrahydrophthalic acid monohydroxypropyl (meth) acrylate, 5-methyl-1,2-cyclohexanedicarboxylic acid monohydroxyethyl (meth) acrylate , Monohydroxyethyl phthalate (meth) acrylate, monohydroxypropyl phthalate (meth) acrylate, monohydroxyethyl maleate (meth) acrylate, hydroxypropyl maleate ( ) Acrylate, tetrahydrophthalic acid mono-hydroxybutyl (meth) acrylate. One or more of these can be appropriately selected and used as necessary.
[0017]
In addition, it contains hydroxyalkyl (meth) acrylate as another monomer from the viewpoint of blending stability of the polymer aqueous dispersion, stain resistance of the coating film, weather resistance, water resistance, and adhesion to various substrates. It is preferable. This content is preferably in the range of 0.1 to 15% by mass in the total polymer. When the content is 0.1% by mass or more, the blending stability of the vinyl copolymer aqueous dispersion, the stain resistance of the coating film, the weather resistance, the water resistance, and the adhesion to various bases are improved. The fall of the water resistance of a coating film and a weather resistance can be suppressed as it is below mass%. A more preferable content is 0.5 to 12% by mass.
Examples of the hydroxyalkyl (meth) acrylate include hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and 4-hydroxybutyl ( And (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, and the like. One or more of these can be appropriately selected and used as necessary.
[0018]
In addition, it contains polyoxyalkylene group as another monomer from the viewpoint of blending stability of vinyl copolymer aqueous dispersion, stain resistance of coating film, weather resistance, water resistance, and adhesion to various bases. It is preferable to contain (meth) acrylate. This content is preferably in the range of 0.1 to 15% by mass in the whole polymer. When the content is 0.1% by mass or more, the blending stability of the vinyl copolymer aqueous dispersion, the stain resistance of the coating film, the weather resistance, the water resistance, and the adhesion to various bases are improved. The fall of the water resistance of a coating film and a weather resistance can be suppressed as it is below mass%. A more preferable content is 0.5 to 12% by mass.
Examples of polyoxyalkylene group-containing (meth) acrylates include hydroxypolyethylene oxide mono (meth) acrylate, hydroxypolypropyleneoxide mono (meth) acrylate, hydroxy (polyethyleneoxide-polypropyleneoxide) mono (meth) acrylate, and hydroxypoly (ethyleneoxide) / Propylene oxide) mono (meth) acrylate, hydroxy (polyethylene oxide-polytetramethylene oxide) mono (meth) acrylate, hydroxy poly (ethylene oxide / tetramethylene oxide) mono (meth) acrylate, hydroxy (polypropylene oxide-polytetramethylene oxide) ) Mono (meth) acrylate, hydroxypoly (propylene oxide / tetramethylene oxide) Terminal hydroxy type polyalkylene oxide group-containing ethylenically unsaturated monomers such as (meth) acrylate, methoxypolyethylene oxide mono (meth) acrylate, lauroxypolyethylene oxide mono (meth) acrylate, stearoxypolyethylene oxide mono (meth) Acrylate, allyloxypolyethylene oxide mono (meth) acrylate, nonylphenoxypolyethyleneoxide mono (meth) acrylate, nonylphenoxypolypropyleneoxide mono (meth) acrylate, octoxy (polyethyleneoxide-polypropyleneoxide) mono (meth) acrylate, nonylphenoxy (poly (Ethylene oxide-propylene oxide) mono (meth) acrylate and other alkyl group end-capped polyalkylene oxide groups Ethylenic unsaturated monomers. One or more of these can be appropriately selected and used as necessary.
[0019]
In addition, from the viewpoint of stain resistance, weather resistance, water resistance, and adhesion to various bases of the coating film, it may contain a self-crosslinkable functional group-containing ethylenically unsaturated monomer as another monomer. preferable. This content is preferably in the range of 0.1 to 15% by mass in the total polymer. When the content is 0.1% by mass or more, the stain resistance, weather resistance, water resistance, and adhesion to various bases of the coating are improved, and when it is 15% by mass or less, the water resistance and weather resistance of the coating are improved. The decline in sex can be suppressed. A more preferable content is 0.5 to 12% by mass.
Here, the self-crosslinkable functional group-containing ethylenically unsaturated monomer means that the resin is dispersed in the resin dispersion and chemically stable while being stored at room temperature, The term refers to an ethylenically unsaturated monomer having a functional group that causes a reaction between side chain functional groups by heating or other external factors to form a chemical bond between the side chain groups.
Examples of the self-crosslinkable functional group-containing ethylenically unsaturated monomer include oxirane group-containing ethylenically unsaturated monomers such as glycidyl (meth) acrylate, N-methylol (meth) acrylamide, N-butoxymethyl (meta ) An alkylol or alkoxyalkyl compound of an ethylenically unsaturated amide such as acrylamide or N-methoxymethyl (meth) acrylamide. One or more of these can be appropriately selected and used as necessary.
[0020]
Moreover, it is preferable to contain a ultraviolet-ray ethylenically unsaturated monomer as a monomer which does not contain silicon from the point of the weather resistance of a coating film. This content is preferably in the range of 0.1 to 10% by mass in the total polymer. When this content is 0.1% by mass or more, the weather resistance of the coating film is improved, and when it is 10% by mass or less, a decrease in polymerization stability can be suppressed. A more preferable content is 0.5 to 8% by mass.
Typical examples of the ultraviolet-resistant ethylenically unsaturated monomer include (meth) acrylate having a light stabilizing action and (meth) acrylate having an ultraviolet-absorbing component.
Examples of the (meth) acrylate having a light stabilizing action include 4- (meth) acryloyloxy-2,2,6,6-tetramethylpiperidine, 4- (meth) acryloylamino-2,2,6,6. -Tetramethylpiperidine, 4- (meth) acryloyloxy-1,2,2,6,6-pentamethylpiperidine, 4- (meth) acryloylamino-1,2,2,6,6-pentamethylpiperidine, 4 -Cyano-4- (meth) acryloyloxy-2,2,6,6-tramethylpiperidine and the like.
Examples of the (meth) acrylate having an ultraviolet absorbing component include 2- [2-hydroxy-5- (meth) acryloyloxyethylphenyl] -2H-benzotriazole, 2- [2-hydroxy-3-t-butyl. -5- (meth) acryloyloxyethylphenyl] -2H-benzotriazole, 2- [2-hydroxy-3-t-amyl-5- (meth) acryloyloxyethylphenyl] -2H-benzotriazole, and the like.
These ultraviolet-resistant ethylenically unsaturated monomers can be used by appropriately selecting one or more kinds as necessary.
In addition, when the stain resistance is more highly required, or when the contamination of the coating film decreases due to the bleed-out of the plasticizer on a soft base having a plasticizer, the silicon-free simple substance is not included. It is also a preferable aspect to introduce a metal-containing radically polymerizable monomer or a specific crosslinking system as a monomer.
Examples of the metal-containing radical polymerizable monomer used in the present invention include a metal-containing polymerizable monomer represented by the following general formula (I).
[0021]
[Chemical 1]

(Wherein R ¹ Is a hydrogen atom or a methyl group, M is a divalent metal ion such as Mg, Ca, Fe, Cu, Zn, Zr, R ² Represents an organic acid residue. )
[0022]
When the organic acid residue is a (meth) acrylic acid residue, it is a metal-containing polymerizable monomer having two unsaturated groups. Specifically, for example, magnesium diacrylate, dimethacrylate Magnesium acrylate, magnesium acrylate methacrylate, calcium diacrylate, calcium dimethacrylate, calcium acrylate methacrylate, iron diacrylate, iron dimethacrylate, iron acrylate methacrylate, copper diacrylate, copper dimethacrylate, acrylic acid Copper methacrylate, zinc diacrylate, zinc dimethacrylate, zinc acrylate methacrylate, zirconium diacrylate, zirconium dimethacrylate, zirconium acrylate methacrylate and the like are preferred.
R of metal-containing polymerizable monomer ² Is an organic acid residue other than a (meth) acrylic acid residue, preferred organic acid residues include monochloroacetic acid, monofluoroacetic acid, propionic acid, octylic acid, versatic acid, isostearic acid, palmitic acid, cresotic acid, Monovalents such as α-naphthoic acid, β-naphthoic acid, benzoic acid, 2,4,5-trichlorophenoxyacetic acid, 2,4-dichlorophenoxyacetic acid, quinolinecarboxylic acid, nitrobenzoic acid, nitronaphthalenecarboxylic acid, and puruvic acid Those derived from organic acids are exemplified.
That is, as specific examples of the metal-containing polymerizable monomer, for example, monochloromagnesium acetate (meth) acrylate, monochlorocalcium acetate (meth) acrylate, monochloroiron acetate (meth) acrylate, monochloroacetate copper (meth) acrylate, Monochloro zinc acetate (meth) acrylate, zirconium monochloro acetate (meth) acrylate, magnesium monofluoroacetate (meth) acrylate, calcium monofluoroacetate (meth) acrylate, iron monofluoroacetate (meth) acrylate, copper monofluoroacetate (meth) Acrylate, zinc monofluoroacetate (meth) acrylate, zirconium monofluoroacetate (meth) acrylate, magnesium propionate (meth) acrylate, calcium propionate (meth) a Relate, iron propionate (meth) acrylate, copper propionate (meth) acrylate, zinc propionate (meth) acrylate, zirconium propionate (meth) acrylate, magnesium octylate (meth) acrylate, calcium octylate (meth) acrylate, Iron octylate (meth) acrylate, copper octylate (meth) acrylate, zinc octylate (meth) acrylate, zirconium octylate (meth) acrylate, magnesium versatate (meth) acrylate, calcium calcium versatate (meth) acrylate, versatic acid Iron (meth) acrylate, versatic acid copper (meth) acrylate, versatic acid zinc (meth) acrylate, versatic acid zirconium (meth) acrylate, isos Magnesium allate (meth) acrylate, calcium isostearate (meth) acrylate, iron (meth) isostearate, copper (meth) isostearate, zinc isostearate (meth) acrylate, zirconium isostearate (meth) acrylate, palmitic acid Magnesium (meth) acrylate, calcium palmitate (meth) acrylate, iron palmitate (meth) acrylate, copper palmitate (meth) acrylate, zinc palmitate (meth) acrylate, zirconium palmitate (meth) acrylate, magnesium cresotate ( (Meth) acrylate, calcium cresotate (meth) acrylate, iron cresotate (meth) acrylate, copper cresotate (meth) acrylate , Zinc cresotinate (meth) acrylate, zirconium cresotate (meth) acrylate, α-magnesium naphthoate (meth) acrylate, α-calcium naphthoate (meth) acrylate, α-iron naphthoate (meth) acrylate, α- Naphthoic acid copper (meth) acrylate, α-naphthoic acid zinc (meth) acrylate, α-naphthoic acid zirconium (meth) acrylate, β-magnesium naphthoic acid (meth) acrylate, β-calcium naphthoic acid (meth) acrylate, β- Naphthoic acid iron (meth) acrylate, β-naphthoic acid copper (meth) acrylate, β-naphthoic acid zinc (meth) acrylate, β-naphthoic acid zirconium (meth) acrylate, magnesium benzoate (meth) acrylate, calcium benzoate ( Meta) Relate, iron benzoate (meth) acrylate, copper benzoate (meth) acrylate, zinc benzoate (meth) acrylate, zirconium benzoate (meth) acrylate, 2,4,5-trichlorophenoxymagnesium acetate (meth) acrylate, 2 , 4,5-trichlorophenoxyacetate calcium (meth) acrylate, 2,4,5-trichlorophenoxyacetate iron (meth) acrylate, 2,4,5-trichlorophenoxyacetate copper (meth) acrylate, 2,4,5- Zinc trichlorophenoxyacetate (meth) acrylate, 2,4,5-trichlorophenoxyacetate zirconium (meth) acrylate, 2,4-dichlorophenoxymagnesium acetate (meth) acrylate, 2,4-dichlorophenoxyacetate calcium (meth) acrylate 2,4-dichlorophenoxyacetic acid iron (meth) acrylate, 2,4-dichlorophenoxyacetic acid copper (meth) acrylate, 2,4-dichlorophenoxyacetic acid zinc (meth) acrylate, 2,4-dichlorophenoxyacetic acid zirconium (meth) Acrylate, magnesium quinolinecarboxylate (meth) acrylate, calcium quinolinecarboxylate (meth) acrylate, quinolinecarboxylate iron (meth) acrylate, quinolinecarboxylate copper (meth) acrylate, quinolinecarboxylate zinc (meth) acrylate, quinolinecarboxylic acid Zirconium (meth) acrylate, magnesium nitrobenzoate (meth) acrylate, calcium nitrobenzoate (meth) acrylate, iron nitrobenzoate (meth) acrylate, copper nitrobenzoate (meth) Acrylate, Zinc nitrobenzoate (meth) acrylate, Zirconium nitrobenzoate (meth) acrylate, Magnesium nitronaphthalenecarboxylate (meth) acrylate, Calcium nitronaphthalenecarboxylate (meth) acrylate, Iron (meth) acrylate nitronaphthalenecarboxylate, Nitrobenzoic acid copper (meth) acrylate, nitrobenzoic acid zinc (meth) acrylate, nitrobenzoic acid zirconium (meth) acrylate, magnesium puruvate (meth) acrylate, calcium puruvate (meth) acrylate, iron puruvate (meth) acrylate Examples thereof include copper (meth) acrylate puruvate, zinc (meth) acrylate, and zirconium (meth) acrylate.
These metal-containing polymerizable monomers can be used by appropriately selecting one or two or more kinds as necessary, and among them, a zinc-containing polymerizable monomer is preferable.
The metal-containing radically polymerizable monomer is preferably contained within a range of 0.1 to 10 parts by mass when the total amount of monomers constituting the vinyl copolymer is 100 parts by mass. When the content is 0.1 parts by mass or more, the stain resistance of the coating film is improved, and when it is 10 parts by mass or less, deterioration of water resistance and weather resistance of the coating film can be suppressed. A more preferable content is 0.5 to 8 parts by mass.
[0023]
Furthermore, in the present invention, a carbonyl group and / or an aldehyde group-containing ethylenically unsaturated monomer is used from the viewpoint of stain resistance, weather resistance, water resistance, strength, solvent resistance, and adhesion to various substrates. It is more preferable to add an organic hydrazine compound having at least two hydrazino groups in the molecule to the aqueous vinyl copolymer dispersion. This is because, when the coating film is dried, a crosslinking reaction proceeds between the carbonyl group in the vinyl copolymer and the hydrazino group of the compounded organic hydrazine compound, and further excellent stain resistance and weather resistance of the coating film. This is because the properties, water resistance, strength, solvent resistance and adhesion to various substrates are obtained.
Examples of the carbonyl group- or aldehyde group-containing ethylenically unsaturated monomer include acrolein, diacetone acrylamide, formyl styrene, vinyl alkyl ketone, etc., preferably 4 to 7 carbon atoms vinyl methyl ketone, vinyl ethyl In addition to ketone, vinyl isobutyl ketone, (meth) acryloxyalkylpropanal, (meth) acrylamide, pivalin aldehyde, diacetone (meth) acrylate, acetonyl acrylate, acetoacetoxyethyl (meth) acrylate, etc., among others, Acrolein, diacetone acrylamide and vinyl methyl ketone are particularly preferred. One or more of these can be appropriately selected and used as necessary.
Examples of the organic hydrazine compound having at least two hydrazino groups in the molecule blended in the vinyl copolymer aqueous dispersion include ethylene-1,2-dihydrazine, propylene-1,3-dihydrazine, butylene. -1,4-dihydrazine, oxalic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, glutaric acid dihydrazide, adipic acid dihydrazide, sebacic acid dihydrazide, maleic acid dihydrazide, fumaric acid dihydrazide, isophthalic acid dihydrazide, etc. Dihydrazides of dicarboxylic acids of number 2 to 15 and 1,3-bis (hydrazinocarboethyl) -5-isopropylhydantoin, 1,3-bis (hydrazinocarboethyl) -5- (2-methylmercaptoethyl) hydantoin, 1-Hide Gino carboxymethyl ethyl-3 hydrazinocarboethyl-isopropyl-5- (2-methyl-mercaptoethyl) organic hydrazine compounds having a hydantoin skeleton such hydantoin and the like. One or more of these can be appropriately selected and used as necessary. Among these, from the viewpoint of stain resistance of the coating film, an organic hydrazine compound having a hydantoin skeleton is preferable, and 1,3-bis (hydrazinocarboethyl) -5-isopropylhydantoin is particularly preferable.
The amount of each used is the number of moles of carbonyl groups and / or aldehyde groups in the vinyl copolymer (P), and the number of moles of hydrazino groups in the organic hydrazine compound blended in the polymer aqueous dispersion. When (Q), the ratio {(P) / (Q)} is preferably in the range of 0.1 to 10, more preferably in the range of 0.8 to 2. This is because when {(P) / (Q)} is less than 0.1, there is a large excess of an organic hydrazine compound that does not cause a crosslinking reaction with a carbonyl group or an aldehyde group, resulting in a decrease in water resistance, and {(P) / If (Q)} exceeds 10, the degree of crosslinking is low, so that the effect of crosslinking cannot be obtained.
The amount of the carbonyl group and / or aldehyde group-containing ethylenically unsaturated monomer used is 0.5 to 10% by mass, preferably 1 to 8% by mass in the total polymer. When the amount used is 0.5% by mass or more, the stain resistance, weather resistance, water resistance, strength, solvent resistance and adhesion to various substrates of the coating film are improved, and when it is 10% by mass or less, polymerization is performed. A decrease in stability and flexibility of the coating film can be suppressed. In addition, when mix | blending the organic hydrazine compound which has two hydrazino groups, it is natural to make said (P) / (Q) appropriate.
By introducing the above metal-containing radical polymerizable monomer and carbonyl / hydrazine crosslinking system, it is possible to prevent the plasticizer migration of the soft base containing the plasticizer and greatly improve the stain resistance. It is particularly preferable to apply to such a soft base.
[0024]
The monomer used together with the monomer whose water solubility in the monomer at 20 ° C. is 0.5 or less and whose homopolymer has a glass transition temperature of 25 ° C. or less, and two or more kinds as necessary. Can be used together.
The glass transition temperature as a vinyl copolymer is not particularly limited as long as it is within the range of use of the monomer described in the claims, but from the viewpoint of non-adhesiveness and stain resistance of the coating film, calculation of Fox It is preferable that the calculated glass transition temperature (Tg) calculated | required by a type | formula is -60 degreeC or more, and -50 degreeC or more is more preferable. Further, it is preferably 40 ° C. or lower, more preferably 30 ° C. or lower, from the viewpoint of crack resistance in a hot / cold repeated test or a freeze-thaw test, that is, followability to a soft base. Here, the formula of Fox is the following relational expression regarding the glass transition temperature (° C.) of the copolymer.
1 / (273 + Tg) = Σ (Wi / (273 + Tgi))
[Wherein Wi represents the mass fraction of monomer i, and Tgi represents Tg (° C.) of the homopolymer of monomer i. ]
In particular, when used as a protective coating for highly flexible materials such as waterproof sheets, the glass transition temperature of a polymer composed of monomers other than silicon-containing monomers may be 0 ° C. or lower. It is more preferable in terms of the base followability of the coating film.
[0025]
The polymer aqueous dispersion can be obtained by polymerizing various monomers by a known polymerization method such as a solution polymerization method, a suspension polymerization method, or an emulsion polymerization method. In particular, it is preferable to obtain a polymer aqueous dispersion in the form of an emulsion by an emulsion polymerization method from the viewpoint of various physical properties such as storage stability of the aqueous coating material, hardness of the coating film, water resistance, weather resistance, and contamination resistance. In order to obtain an emulsion by the emulsion polymerization method, for example, a method in which a monomer mixture is supplied into a polymerization system in the presence of a surfactant and polymerization is carried out with a water-soluble initiator, and for example, an organic peroxide is used. A known method such as a method of polymerizing with a redox initiator in which a reducing agent such as sodium thiosulfate is combined can be used.
Examples of the initiator include inorganic peroxides such as potassium persulfate, sodium persulfate, ammonium persulfate, and hydrogen peroxide; benzoyl peroxide, t-butyl hydroperoxide, di-t-butyl hydroperoxide, t- Organic peroxides such as butyl peroxybenzoate and cumene hydroperoxide; 2,2-azobisisobutyronitrile, 2,2-azobis (2-diaminopropane) hydrochloride, 2,2-azobis (2,4 -Azo compounds such as (dimethylvaleronitrile); redox compounds represented by combinations of inorganic peroxides and sodium bisulfite or Rongalite or sodium ascorbate, organic oxides and sodium hydrogensulfate or Rongalite or sodium ascorbate Catalyst; It is.
[0026]
The emulsion obtained by the emulsion polymerization method has a stability of the system by adjusting the pH of the system to neutral to weakly alkaline, that is, in the range of about pH 6.5 to 10.0 by adding a basic compound after polymerization. Can be increased. Examples of the basic compound include ammonia, triethylamine, propylamine, dibutylamine, amylamine, 1-aminooctane, 2-dimethylaminoethanol, ethylaminoethanol, 2-diethylaminoethanol, 1-amino-2-propanol, 2 -Amino-1-propanol, 2-amino-2-methyl-1-propanol, 3-amino-1-propanol, 1-dimethylamino-2-propanol, 3-dimethylamino-1-propanol, 2-propylaminoethanol , Ethoxypropylamine, aminobenzyl alcohol, morpholine, sodium hydroxide, potassium hydroxide and the like.
In the case of adjusting the molecular weight of the polymer, it can be adjusted by using a known chain transfer agent such as n-dodecyl mercaptan, t-dodecyl mercaptan, α-methylstyrene dimer as the molecular weight adjusting agent.
Moreover, when making the polymer which comprises a polymer into 100 mass parts, it is preferable to add 0.1-10 mass parts of surfactant. The presence of 0.1 part by mass or more of the surfactant improves the storage stability of the vinyl copolymer aqueous dispersion, and also improves the stability during polymerization when emulsion polymerization is performed in the presence of a surfactant. To do. In addition, by setting the surfactant to 10 parts by mass or less, it is possible to maintain stability at the time of coating and blending, stability over time, and the like without impairing water resistance. A more preferable content is 0.5 to 8 parts by mass.
Examples of the surfactant include various conventionally known anionic, cationic or nonionic surfactants, and polymer emulsifiers. A so-called reactive emulsifier having an ethylenically unsaturated bond in the surfactant component can also be used.
[0027]
The aqueous coating material of this invention is normally used in 20-80 mass% of solid content. In addition, various pigments, antifoaming agents, pigment dispersants, leveling agents, anti-sagging agents, matting agents, UV absorbers, antioxidants, heat resistance improvers, slips are used to develop high performance coating materials. Agents, preservatives, plasticizers and the like may be included. Furthermore, you may mix and use hardening agents, such as another emulsion resin, water-soluble resin, a viscosity control agent, and melamines.
Thus, the paints formulated and formed as described above are urethane rubber type, acrylic rubber type, chloroprene rubber type, silicon rubber type, vinyl chloride rubber type, vulcanized rubber type, non-vulcanized rubber type, olefin type thermoplastic elastomer, It is applied to a soft base such as polyurethane resin, polyacrylic resin, polyvinyl chloride resin, soft polyester resin, soft epoxy resin, polysulfide, rubber asphalt.
In particular, waterproof coating for waterproof sheets such as EPDM rubber, polyvinyl chloride, polyethylene, olefinic thermoplastic elastomer, urethane, etc. that form a sheet in advance, such as waterproof sheets and urethane coatings. It is suitable as.
In order to form a film on the surface of various materials using the aqueous coating material of the present invention, various coating methods such as spray coating, roller coating, bar coating, air knife coating, brush coating, and dipping are used. What is necessary is just to select and implement the coating method suitably. Moreover, the aqueous coating material of this invention can obtain the film formed sufficiently by drying at room temperature or heat-drying at 50-180 degreeC.
[0028]
【Example】
EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited at all by these. In the following description, “part” is based on mass. About the physical property test of the aqueous coating material, the paint was prepared with the following composition, and the test was performed according to the following method.
<Production of water-based coating material (white enamel paint)>
707 g of Typeke CR-97 (produced by Ishihara Sangyo Co., Ltd., chlorinated titanium oxide) as titanium oxide, 12 g of Adekacol W-193 (produced by Asahi Denka Kogyo Co., Ltd.) as a pigment dispersant, and Surfynol DF-58 as an antifoam 25 g (produced by Air Products Co., Ltd.) is thoroughly mixed with 256 g of deionized water, glass beads are added, and pigment dispersion is performed with a high-speed disperser for 30 minutes, and then the glass beads are filtered with a 300 mesh nylon bottle. A mill base for evaluation was obtained (solid content: 71% by mass).
Next, 42.7 g of the above-mentioned mill base for evaluation was used for 100 g of a copolymer aqueous dispersion described later (based on a solid content of 45% by mass), and Kyowanol M (manufactured by Kyowa Hakko Co., Ltd.) as a film-forming aid. In an appropriate amount so that the minimum film-forming temperature is 0 ° C. (however, when the minimum film-forming temperature is already 0 ° C. or less, Kyowanol M is not added), 3 g of propylene glycol, and RHEOLATE 350 ( RHEOX (manufactured by RHEOX Co., Ltd.) was added in an order of 0.5 g, and the mixture was sufficiently stirred, and adjusted with Ford Cup # 4 by adding deionized water to about 30 seconds. Thereafter, filtration was again performed using a 300 mesh nylon bag to obtain an aqueous coating material for evaluation (white enamel paint).
[0029]
<Production of soft base>
In producing a polyacrylic resin-based soft base, an aqueous acrylic resin was obtained by the following procedure.
First, 100 parts of a monomer mixture of 70 parts of 2-ethylhexyl acrylate, 19 parts of n-butyl methacrylate, 5 parts of methyl methacrylate, 4 parts of 2-hydroxy methacrylate, and 2 parts of methacrylic acid, Adekari Soap SR as a surfactant 1 part of -10 and 50 parts of deionized water were sufficiently mixed to prepare a pre-emulsion in a uniform emulsified state (hereinafter abbreviated as “PE solution”). Next, 70 parts of deionized water, 0.5 part of Adeka Soap SR-10, and 10 parts of PE solution are charged into a flask equipped with a stirrer, a reflux condenser, a temperature controller, a dropping pump, and a nitrogen introduction pipe. The internal temperature of the reaction vessel was raised to 80 ° C. Thereafter, 0.1 part of ammonium persulfate dissolved in 1 part of deionized water was added and kept for 1 hour, thereby producing seed particles.
Further, all of the remaining PE solution and 0.2 part of sodium persulfate dissolved in 10 parts of deionized water were dropped in parallel over 3 hours while maintaining the internal temperature of the reaction vessel at 80 ° C. After completion of the dropping, the internal temperature was maintained at 80 ° C. for 2 hours to increase the conversion rate to the resin, and the reaction was completed. Then, it cools to 60 degreeC, 28% ammonia aqueous solution is added so that the pH of an emulsion may be between 8-10, and it stirs for 30 minutes, and obtains the water-based acrylic resin for producing a polyacrylic resin-type soft base | substrate. It was.
Next, 42.7 g of the above-mentioned mill base for evaluation, 3 g of propylene glycol, and 0.5 g of RHEOLATE 350 (manufactured by RHEOX Co., Ltd.) as a thickener were sequentially added to 100 g of this aqueous acrylic resin, and stirred sufficiently. Then, it was adjusted by adding deionized water so that it would be about 30 seconds in Ford Cup # 4. Thereafter, filtration was again performed using a 300 mesh nylon bag to obtain a white enamel paint for producing a polyacrylic resin-based soft base.
White enamel paint for making polyacrylic resin-based soft base on zinc phosphate-treated steel plate (Bondelite # 100-treated steel plate, thickness 0.8mm, 70mm x 150mm) so that the dry film thickness becomes 100μm After spray coating, the mixture was allowed to stand at room temperature for 3 hours, spray-coated again so that the dry film thickness was 100 μm, and left at room temperature for 1 week to make a polyacrylic resin-based soft base.
[0030]
<Preparation of test plate>
An aqueous coating material for evaluation (white enamel paint) is spray-coated on the waterproof sheet made of EPDM rubber and the above polyacrylic resin-based soft base so that the dry film thickness is 50 μm, then left at room temperature for 3 hours and dried again. A sample that was spray-coated so as to have a film thickness of 50 μm and allowed to stand at room temperature for 1 week was used as a test article for substrate follow-up, contamination resistance, weather resistance, and water resistance.
[0031]
<Test method>
(1) Substrate following ability
The specimen was immersed in 20 ± 2 ° C. water for 18 hours, immediately cooled in a −20 ± 3 ° C. incubator for 3 hours, and then heated in another 50 ± 3 ° C. incubator for 3 hours. This 24 hour operation is performed as one cycle, and the number of cycles until an abnormality is observed in the coating film state (coating peeling, cracking and swelling, discoloration and gloss reduction) is determined according to the following criteria. did.
“A”: No abnormality was found even after 30 cycles.
“◯”: No abnormality was observed until 20 to 29 cycles.
“◯ △”: No abnormality was observed until 10 to 19 cycles.
“Δ”: No abnormality was observed until 5 to 9 cycles.
“Δ ×”: No abnormality was observed until 1 to 4 cycles.
“×”: An abnormality was observed in one cycle.
(2) Pollution resistance
The test board was placed on an outdoor exposure table (Itoman City, Okinawa Prefecture) at 45 degrees south and exposed for one year from April 2002 to March 2003. ΔL was measured with a color difference meter. ΔL was used as a contamination index, and the determination was made according to the following criteria.
“◎”: Less than 2.5.
“◯”: 2.5 or more and less than 5.0.
“Δ”: 5.0 or more and less than 7.5.
“×”: 7.5 or more
(3) Weather resistance
The test plate is cut into a size of 70 mm × 50 mm, and the test plate is put into a die plastic metal weather KU-R4-W type (manufactured by Daipura Wintes Co., Ltd.). Test cycle: irradiation 6 hours / condensation 2 hours, UV intensity: 65 mW / cm ² Black panel temperature: 63 ° C. during irradiation / 30 ° C. during condensation, humidity: 50% RH during irradiation / 96% RH during condensation, 60 ° gloss retention after 600 hours as an indicator of weather resistance Judgment was made according to the following criteria.
“◎”: 80% or more.
“◯”: 70% or more and less than 80%.
“△”: 60% or more and less than 70%.
"X": Less than 60%.
(4) Water resistance
The test plate was immersed in water at 20 ± 2 ° C. for 1 month and then dried at room temperature for 2 hours. The state of the coating film and the 60 ° gloss retention were used as indicators of water resistance, and the determination was made according to the following criteria.
“◎”: No cracking, swelling, or peeling, and gloss retention of 80% or more.
“◯”: No cracking, swelling, or peeling, and gloss retention of 70% or more.
“△”: No cracking, blistering, or peeling, and gloss retention of 60% or more.
“X”: Any one of the items did not satisfy the items shown in the above water resistance evaluation “Δ”.
[0032]
<Production Example 1> Method for producing silicon-containing polymer used in silicon component introduction method (a)
A composition comprising 98 parts of a cyclic dimethylsiloxane oligomer 3 to 7-mer mixture, 2 parts of γ-methacryloyloxypropyltrimethoxysilane, 310 parts of deionized water and 1 part of sodium dodecylbenzenesulfonate was premixed with a homomixer. 200 kg / cm using a pressure homogenizer ² The silicon raw material pre-emulsion was obtained by forcibly emulsifying under the pressure of
Next, 90 parts of water and 9 parts of dodecylbenzenesulfonic acid were charged into a flask equipped with a stirrer, a reflux condenser, a temperature controller and a dropping pump, and while stirring, the above silicon was kept at 85 ° C. The raw material pre-emulsion was dropped over 4 hours. After completion of the dropwise addition, the polymerization is further allowed to proceed for 1 hour, cooled, added with dodecylbenzenesulfonic acid and an equimolar amount of sodium hydroxide, and a polyorganosiloxane polymer aqueous dispersion, which is a silicon-containing monomer ( A) was obtained. The solid content was 20%.
[0033]
<Examples 1 and 2 (Method for introducing silicon component (I))>
In a flask equipped with a stirrer, a reflux condenser, a temperature controller, a dropping pump, and a nitrogen inlet tube, 5 parts of the polyorganosiloxane polymer aqueous dispersion (A) described in Production Example 1 (1 part as a solid content), desorption 70 parts of ionic water, 0.8 part of surfactant (reactive anionic surfactant, manufactured by Asahi Denka Co., Ltd., trade name Adekaria Soap SR-10), and silicon of the initial charge composition part shown in Table 2 below. 29 parts of a monomer not contained and 0.1 part of t-butyl hydroperoxide were charged and stirred at room temperature for 1 hour in a nitrogen atmosphere. And after raising the internal temperature of a flask to 50 degreeC, the aqueous solution of 0.0002 part of ferrous sulfate, 0.05 part of Rongalite, and 1 part of deionized water was added, and stirring was continued for 1 hour. Thereafter, the internal temperature of the flask was raised to 80 ° C., and 70 parts of the silicone-free monomer, 35 parts of deionized water, and 2 parts of Adekari Soap SR-10 shown in Table 2 below were pre-emulsified. The dispersed PE solution and 2 parts of 5% aqueous solution of ammonium persulfate were dropped in two series over 2 hours. During this dropping, the internal temperature of the flask is maintained at 80 ° C. After the dropping is completed, the flask is further maintained at 80 ° C. for 2 hours, then cooled to room temperature, neutralized with a 28% aqueous ammonia solution, and a vinyl copolymer. An aqueous dispersion was obtained.
The solid content and the minimum film-forming temperature of this vinyl copolymer aqueous dispersion are shown in Table 2 below. Also, an aqueous coating material (white enamel paint) was prepared using this vinyl copolymer aqueous dispersion, and tests for substrate follow-up property, stain resistance, weather resistance, and water resistance were conducted. The results are shown in Table 5 below.
[0034]
<Example 3 (Method for introducing silicon component (I))>
In a flask equipped with a stirrer, a reflux condenser, a temperature controller, a dropping pump, and a nitrogen introduction tube, 25 parts of the polyorganosiloxane polymer aqueous dispersion (A) described in Production Example 1 (5 parts as a solid content) was removed. 70 parts of ionic water, 35 parts of a monomer containing no silicon in the initial charge composition part shown in Table 2 below, and 0.1 part of t-butyl hydroperoxide were charged and stirred at room temperature for 1 hour in a nitrogen atmosphere. . And after raising the internal temperature of a flask to 50 degreeC, the aqueous solution of 0.0002 part of ferrous sulfate, 0.05 part of Rongalite, and 1 part of deionized water was added, and stirring was continued for 1 hour. Thereafter, the internal temperature of the flask was raised to 80 ° C., and 60 parts of a silicone-free monomer, 30 parts of deionized water, and 1 part of Adekari Soap SR-10 shown in Table 2 below were pre-emulsified. The dispersed PE solution and 2 parts of 5% aqueous solution of ammonium persulfate were dropped in two series over 2 hours. During this dropping, the internal temperature of the flask is maintained at 80 ° C. After the dropping is completed, the flask is further maintained at 80 ° C. for 2 hours, then cooled to room temperature, neutralized with a 28% aqueous ammonia solution, and a vinyl copolymer. An aqueous dispersion was obtained.
The solid content and the minimum film-forming temperature of this vinyl copolymer aqueous dispersion are shown in Table 2 below. Also, an aqueous coating material (white enamel paint) was prepared using this vinyl copolymer aqueous dispersion, and tests for substrate follow-up property, stain resistance, weather resistance, and water resistance were conducted. The results are shown in Table 5 below.
[0035]
<Example 4 (Method for introducing silicon component (I))>
In a flask equipped with a stirrer, a reflux condenser, a temperature controller, a dropping pump, and a nitrogen introduction tube, 25 parts of the polyorganosiloxane polymer aqueous dispersion (A) described in Production Example 1 (5 parts as a solid content) was removed. 70 parts of ionic water, 35 parts of a monomer containing no silicon in the initial charge composition part shown in Table 2 below, and 0.1 part of t-butyl hydroperoxide were charged and stirred at room temperature for 1 hour in a nitrogen atmosphere. . And after raising the internal temperature of a flask to 50 degreeC, the aqueous solution of 0.0002 part of ferrous sulfate, 0.05 part of Rongalite, and 1 part of deionized water was added, and stirring was continued for 1 hour. Thereafter, the internal temperature of the flask was raised to 80 ° C., and 60 parts of the silicone-free monomer, 30 parts of deionized water, and 2 parts of Adekari Soap SR-10 shown in Table 2 below were pre-emulsified. The dispersed PE solution and 2 parts of 5% aqueous solution of ammonium persulfate were dropped in two series over 2 hours. During the dropping, the internal temperature of the flask is maintained at 80 ° C., and after the dropping is completed, the flask is further maintained at 80 ° C. for 2 hours, and then cooled to room temperature, 2-amino-2-methyl-1-propanol (AMP) Neutralized. Finally, 12.5 parts of a 20% aqueous solution of an organic hydrazine compound shown in Table 2 below was added to obtain an aqueous vinyl copolymer dispersion.
The solid content and the minimum film-forming temperature of this vinyl copolymer aqueous dispersion are shown in Table 2 below. Also, an aqueous coating material (white enamel paint) was prepared using this vinyl copolymer aqueous dispersion, and tests for substrate follow-up property, stain resistance, weather resistance, and water resistance were conducted. The results are shown in Table 5 below.
[0036]
<Examples 5 to 9 (Silicon component introduction method (I))>
In a flask equipped with a stirrer, a reflux condenser, a temperature controller, a dropping pump, and a nitrogen introduction pipe, 50 parts (10 parts as a solid content) of the polyorganosiloxane polymer aqueous dispersion (A) described in Production Example 1 were removed. 50 parts of ionic water, 30 parts of silicon-free monomer of initial charge composition part shown in Table 2 below, and 0.1 part of t-butyl hydroperoxide were charged and stirred at room temperature for 1 hour in a nitrogen atmosphere. . And after raising the internal temperature of a flask to 50 degreeC, the aqueous solution of 0.0002 part of ferrous sulfate, 0.05 part of Rongalite, and 1 part of deionized water was added, and stirring was continued for 1 hour. Thereafter, the internal temperature of the flask was raised to 80 ° C., and 60 parts of a silicone-free monomer, 30 parts of deionized water, and 1 part of Adekari Soap SR-10 shown in Table 2 below were pre-emulsified. The dispersed PE solution and 2 parts of 5% aqueous solution of ammonium persulfate were dropped in two series over 2 hours. During this dropping, the internal temperature of the flask is maintained at 80 ° C. After the dropping is completed, the flask is further maintained at 80 ° C. for 2 hours, then cooled to room temperature, neutralized with a 28% aqueous ammonia solution, and a vinyl copolymer. An aqueous dispersion was obtained.
The solid content and the minimum film-forming temperature of this vinyl copolymer aqueous dispersion are shown in Table 2 below. Also, an aqueous coating material (white enamel paint) was prepared using this vinyl copolymer aqueous dispersion, and tests for substrate follow-up property, stain resistance, weather resistance, and water resistance were conducted. The results are shown in Table 5 below.
[0037]
<Example 10 (Method for introducing silicon component (I))>
In a flask equipped with a stirrer, a reflux condenser, a temperature controller, a dropping pump, and a nitrogen introduction pipe, 50 parts (10 parts as a solid content) of the polyorganosiloxane polymer aqueous dispersion (A) described in Production Example 1 were removed. 50 parts of ionic water, 30 parts of silicon-free monomer of initial charge composition part shown in Table 2 below, and 0.1 part of t-butyl hydroperoxide were charged and stirred at room temperature for 1 hour in a nitrogen atmosphere. . And after raising the internal temperature of a flask to 50 degreeC, the aqueous solution of 0.0002 part of ferrous sulfate, 0.05 part of Rongalite, and 1 part of deionized water was added, and stirring was continued for 1 hour. Thereafter, the internal temperature of the flask was raised to 80 ° C., and 60 parts of the silicone-free monomer, 30 parts of deionized water, and 2 parts of Adekari Soap SR-10 shown in Table 2 below were pre-emulsified. The dispersed PE solution and 2 parts of 5% aqueous solution of ammonium persulfate were dropped in two series over 2 hours. During the dropping, the internal temperature of the flask was kept at 80 ° C., and after the dropping was finished, the flask was further kept at 80 ° C. for 2 hours, then cooled to room temperature and neutralized with AMP. Finally, 12.5 parts of a 20% aqueous solution of an organic hydrazine compound shown in Table 2 below was added to obtain an aqueous vinyl copolymer dispersion.
The solid content and the minimum film-forming temperature of this vinyl copolymer aqueous dispersion are shown in Table 3 below. Also, an aqueous coating material (white enamel paint) was prepared using this vinyl copolymer aqueous dispersion, and tests for substrate follow-up property, stain resistance, weather resistance, and water resistance were conducted. The results are shown in Table 5 below.
[0038]
<Example 11 (Method for introducing silicon component (I))>
In a flask equipped with a stirrer, a reflux condenser, a temperature controller, a dropping pump, and a nitrogen introduction tube, 125 parts of the polyorganosiloxane polymer aqueous dispersion (A) described in Production Example 1 (25 parts as solid content), The initial charge composition part shown in Table 2 was charged with 25 parts of silicon-free monomer and 0.1 part of t-butyl hydroperoxide, and stirred at room temperature for 1 hour in a nitrogen atmosphere. And after raising the internal temperature of a flask to 50 degreeC, the aqueous solution of 0.0002 part of ferrous sulfate, 0.05 part of Rongalite, and 1 part of deionized water was added, and stirring was continued for 1 hour. Thereafter, the internal temperature of the flask was raised to 80 ° C., and 50 parts of a monomer not containing silicon, 25 parts of deionized water, and 0.5 part of Adekari Soap SR-10 shown in Table 2 below were added. The PE solution emulsified and dispersed in advance and 2 parts of a 5% aqueous solution of ammonium persulfate were dropped in two series over 2 hours. During this dropping, the internal temperature of the flask is maintained at 80 ° C. After the dropping is completed, the flask is further maintained at 80 ° C. for 2 hours, then cooled to room temperature, neutralized with a 28% aqueous ammonia solution, and a vinyl copolymer. An aqueous dispersion was obtained.
The solid content and the minimum film-forming temperature of this vinyl copolymer aqueous dispersion are shown in Table 3 below. Also, an aqueous coating material (white enamel paint) was prepared using this vinyl copolymer aqueous dispersion, and tests for substrate follow-up property, stain resistance, weather resistance, and water resistance were conducted. The results are shown in Table 5 below.
[0039]
<Example 12 (Method for introducing silicon component (I))>
In a flask equipped with a stirrer, a reflux condenser, a temperature controller, a dropping pump and a nitrogen introduction tube, 200 parts of the polyorganosiloxane polymer aqueous dispersion (A) described in Production Example 1 (40 parts as a solid content), the following The initial charge composition part shown in Table 2 was charged with 25 parts of silicon-free monomer and 0.1 part of t-butyl hydroperoxide, and stirred at room temperature for 1 hour in a nitrogen atmosphere. And after raising the internal temperature of a flask to 50 degreeC, the aqueous solution of 0.0002 part of ferrous sulfate, 0.05 part of Rongalite, and 1 part of deionized water was added, and stirring was continued for 1 hour. Thereafter, the internal temperature of the flask was raised to 80 ° C., and 35 parts of a monomer not containing silicon, 18 parts of deionized water, and 0.5 part of Adecare Soap SR-10 as shown in Table 2 below were added. The PE solution emulsified and dispersed in advance and 2 parts of a 5% aqueous solution of ammonium persulfate were dropped in two series over 2 hours. During this dropping, the internal temperature of the flask is maintained at 80 ° C. After the dropping is completed, the flask is further maintained at 80 ° C. for 2 hours, then cooled to room temperature, neutralized with a 28% aqueous ammonia solution, and a vinyl copolymer. An aqueous dispersion was obtained.
The solid content and the minimum film-forming temperature of this vinyl copolymer aqueous dispersion are shown in Table 3 below. Also, an aqueous coating material (white enamel paint) was prepared using this vinyl copolymer aqueous dispersion, and tests for substrate follow-up property, stain resistance, weather resistance, and water resistance were conducted. The results are shown in Table 5 below.
[0040]
<Examples 13 and 14 (Silicon component introduction method (b))>
In a flask equipped with a stirrer, a reflux condenser, a temperature controller, a dropping pump and a nitrogen introduction tube, 60 parts of deionized water, 35 parts of a monomer containing no silicon in the initial charge composition part shown in Table 2 below, Adekaria 1 part of soap SR-10 was charged and stirred at room temperature for 1 hour under a nitrogen atmosphere. And after raising the internal temperature of a flask to 80 degreeC, 10 parts of 5% aqueous solution of ammonium persulfate was added, and stirring was continued for 1 hour. Thereafter, the temperature of the flask was lowered to 60 ° C.
Next, 35 parts of deionized water, 5 parts of a monomer containing silicon, 65 parts of a monomer not containing silicon, and 2 parts of Adeka Soap SR-10 are pre-emulsified and dispersed. The PE solution, 2 parts of a 5% aqueous solution of ammonium persulfate, and 1 part of a 5% aqueous solution of sodium hydrogensulfite were added dropwise over 3 hours over 3 hours. During this dropping, the internal temperature of the flask is maintained at 60 ° C., and after the dropping is completed, the flask is further maintained at 60 ° C. for 2 hours, then cooled to room temperature, neutralized with a 28% aqueous ammonia solution, and a vinyl copolymer. An aqueous dispersion was obtained.
The solid content and the minimum film-forming temperature of this vinyl copolymer aqueous dispersion are shown in Table 3 below. Also, an aqueous coating material (white enamel paint) was prepared using this vinyl copolymer aqueous dispersion, and tests for substrate follow-up property, stain resistance, weather resistance, and water resistance were conducted. The results are shown in Table 5 below.
[0041]
<Example 15 (Silicon component introduction method (c))>
In a flask equipped with a stirrer, a reflux condenser, a temperature controller, a dropping pump and a nitrogen introduction tube, 60 parts of deionized water, 35 parts of a monomer containing no silicon in the initial charge composition part shown in Table 2 below, Adekaria 1 part of soap SR-10 was charged and stirred at room temperature for 1 hour under a nitrogen atmosphere. And after raising the internal temperature of a flask to 80 degreeC, 10 parts of 5% aqueous solution of ammonium persulfate was added, and stirring was continued for 1 hour.
Next, 35 parts of deionized water, 5 parts of a monomer containing silicon and 65 parts of a monomer not containing silicon, and 2 parts of Adeka Soap SR-10 are added with a homomixer. The PE solution was prepared by stirring for 10 minutes at a stirring speed of 10,000 rpm. This PE solution and 2 parts of a 5% aqueous solution of ammonium persulfate were dropped in two series over 2 hours. During this dropping, the internal temperature of the flask is maintained at 80 ° C. After the dropping is completed, the flask is further maintained at 80 ° C. for 2 hours, then cooled to room temperature, neutralized with a 28% aqueous ammonia solution, and a vinyl copolymer. An aqueous dispersion was obtained.
The solid content and the minimum film-forming temperature of this vinyl copolymer aqueous dispersion are shown in Table 3 below. Also, an aqueous coating material (white enamel paint) was prepared using this vinyl copolymer aqueous dispersion, and tests for substrate follow-up property, stain resistance, weather resistance, and water resistance were conducted. The results are shown in Table 5 below.
[0042]
<Comparative Examples 1 and 2 (acrylic emulsion)>
First, 100 parts of a monomer not containing silicon, 2 parts of Adeka Soap SR-10 and 50 parts of deionized water shown in Table 4 below were sufficiently mixed to prepare a PE solution.
Next, 70 parts of deionized water and 0.5 part of Adeka Soap SR-10 are introduced into a flask equipped with a stirrer, a reflux condenser, a temperature controller, a dropping pump, and a nitrogen introduction pipe, and the internal temperature of the reaction vessel is reduced. The temperature was raised to 80 ° C.
Thereafter, PE solution emulsified in advance and 5 parts of 5% ammonium persulfate aqueous solution were dropped in two series over 3 hours. During this dropping, the internal temperature of the flask is maintained at 80 ° C. After the dropping is completed, the flask is further maintained at 80 ° C. for 2 hours, then cooled to room temperature, neutralized with a 28% aqueous ammonia solution, and a vinyl copolymer. An aqueous dispersion was obtained.
Table 4 below shows the solid content and the minimum film-forming temperature of this vinyl copolymer aqueous dispersion. Also, an aqueous coating material (white enamel paint) was prepared using this vinyl copolymer aqueous dispersion, and tests for substrate follow-up property, stain resistance, weather resistance, and water resistance were conducted. The results are shown in Table 5 below.
[0043]
[Table 2]

[0044]
[Table 3]

[0045]
[Table 4]

[0046]
[Table 5]

[0047]
The abbreviations in Tables 2 to 4 indicate the following compounds.
"N-BMA": n-butyl methacrylate
"N-BA": n-butyl acrylate
・ "2-EHA": 2-ethylhexyl acrylate
"T-BMA": t-butyl methacrylate
"CHMA": cyclohexyl methacrylate
・ "MAA": Methacrylic acid
・ "2-HEMA": 2-hydroxyethyl methacrylate
"Blemmer 70PEP350B": hydroxy (polyethylene glycol-polypropylene glycol) monomethacrylate (trade name, manufactured by NOF Corporation)
"Adekastab LA-82": 1,2,2,6,6-pentamethyl-4-piperidyl methacrylate (trade name, manufactured by Asahi Denka Kogyo Co., Ltd.)
・ DAAm: Diacetone acrylamide
・ "MMA": Methyl methacrylate
・ "EA": Ethyl acrylate
"Adekaria soap SR-10": reactive anionic surfactant (trade name, manufactured by Asahi Denka Co., Ltd.)
"DBSNa": sodium dodecylbenzenesulfonate
"FM0725": Silicone macromonomer, molecular weight 10,000 (trade name, manufactured by Chisso Corporation)
"VDH": 1,3-bis (hydrazinocarboethyl) -5-isopropylhydantoin (trade name Amicure VDH, manufactured by Ajinomoto Fine Techno Co., Ltd.)
"AMP": 2-amino-2-methyl-1-propanol
[0048]
【The invention's effect】
As described above, according to the present invention, the solubility of water in the monomer unit (A) containing silicon and the monomer at 20 ° C. is 0.5 or less, and the glass transition temperature of the homopolymer is By containing a polymer containing a monomer unit (B) derived from a monomer that does not contain silicon at 25 ° C. or less, it has excellent followability to soft substrates, stain resistance, weather resistance, and water resistance. It is possible to provide a water-based coating material that also has both.
The aqueous low-pollution coating material of the present invention is extremely useful industrially. Specifically, for example, urethane rubber, acrylic rubber, chloroprene rubber, silicon rubber, vinyl chloride rubber, vulcanized rubber, Surface finishing of various soft substrates such as non-vulcanized rubber, olefin thermoplastic elastomer, polyurethane resin, polyacrylic resin, polyvinyl chloride resin, soft polyester resin, soft epoxy resin, polysulfide, rubber asphalt It is extremely useful as a water-based coating material mainly used for protecting buildings such as buildings and civil engineering structures.

Claims (5)

A monomer unit (A) containing silicon;
A monomer unit (B) derived from a silicon-free monomer having a water solubility in a monomer at 20 ° C. of 0.5 or less and a glass transition temperature of the homopolymer of 25 ° C. or less; A water-based coating material for protecting a soft base, comprising a polymer. The aqueous coating material for soft base protection according to claim 1, comprising a polymer having a monomer unit (B) content of 50 to 99% by mass. The monomer for constituting the monomer unit (B), wherein a monomer containing no silicon and having a glass transition temperature of 0 ° C. or lower is used, for protecting a soft base according to claim 1 Water-based coating material. The aqueous coating material for soft ground protection according to claim 1, comprising a polymer having a monomer unit (B) content of 35 to 90% by mass. Does not contain silicon in the presence of polysiloxane particles dispersed in an aqueous medium, the solubility of water in the monomer at 20 ° C. is 0.5 or less, and the glass transition temperature of the homopolymer is 25 ° C. or less The aqueous coating material for soft ground protection according to any one of claims 1 to 4, obtained by polymerizing a monomer or a mixture of the monomer and another monomer.