JP3945591B2 - Antifouling coating composition, coating film formed from the antifouling coating composition, antifouling method using the antifouling coating composition, and hull or underwater structure coated with the coating - Google Patents

Description

【００１５】
（Ｒ⁴〜Ｒ⁶は水素原子、炭素数１〜１８のアルコキシ基、シクロアルコキシ基、などを示し、Ｒ⁷は炭素数１〜１８のアルキル基などを示し、ｎは１〜３の整数を示す）で表されるアルコキシ基含有珪素化合物を含有した塗料組成物が開示されており、また該公報の発明の構成・作用の欄には、該塗料組成物には酸化亜鉛などの顔料、塩素化パラフィンなどの可塑剤、アクリル樹脂などの樹脂が必要に応じて含まれていてもよい旨記載されている。また、その実施例には、トリｎ−ブチルシリルメタクリレート系重合体、酸化亜鉛、弁柄およびタルクなどを含む塗料組成物が開示されている。しかしながら、該公報においては、得られる塗膜の特に乾燥時の耐クラック性、あるいは喫水線近傍などでの経時変化の安定性については何等教示されていない。
【００１６】
また、特開平７-１０２１９３号公報には、式：
【００１７】
【化２】

【００１８】
（但し、式中Ｒ¹〜Ｒ³はいずれもアルキル基、アリール基の中から選ばれた基であって、互いに同一の基であっても異なる基であってもよい。Ｘはアクリロイルオキシ基、メタクリロイルオキシ基、マレオイルオキシ基またはフマロイルオキシ基である。）で表される単量体Ａと、式：Ｙ−（ＣＨ₂ＣＨ₂Ｏ）_n−Ｒ⁴（但しＲ⁴はアルキル基またはアリール基であり、Ｙはアクリロイルオキシ基またはメタクリロイルオキシ基であり、ｎは１〜２５の整数である。）で表される単量体Ｂとを含む単量体混合物の共重合体と、防汚剤とを必須成分として含有する塗料組成物が開示され、またその発明の作用・効果の項には、防汚剤として酸化亜鉛などが例示され、塗料固形分中０．１〜８０重量％の量で使用される旨記載されている。しかしながら、該公報においては、得られる塗膜の特に乾燥時の耐クラック性、あるいは経時変化の安定性については何等教示されていない。
【００１９】
このように、上記何れの公報記載にも、どんな組成の防汚塗料からなる塗膜が、特に乾燥時の耐クラック性、あるいは水中への浸漬と乾燥空気中への暴露とが繰返されるような環境下での経時変化の安定性に優れるかという点ついては何等教示されていない。
【００２０】
【発明の目的】
本発明は、上記のような従来技術に伴う問題点を解決しようとするものであって、特に船体、水中構造物などの喫水線より上部にあるなど乾燥下での耐クラック性、耐剥離性などの物性に優れ、しかも喫水線の変動により乾燥下に晒されたり、海水中に浸漬されたりすることによっても経時変化しにくく、長期安定性に優れた塗膜を形成でき、また、塗膜に盤木などの圧力が加えられてもこの圧力によるダメージを実用上問題のない程度まで抑制できるような強度に優れた塗膜を形成できるような防汚塗料組成物を提供することを目的としている。
【００２１】
本発明は、さらに好ましくは上記目的に加えて水中での耐クラック性、防汚性、自己研磨性（消耗性）にも優れているような防汚塗膜を形成でき、しかも貯蔵安定性に優れているような防汚塗料組成物を提供することを目的としている。
【００２２】
また、本発明は、このような防汚塗料組成物から形成されている塗膜および該防汚塗料組成物を用いた防汚方法並びに該塗膜で被覆された船体または水中構造物を提供することを目的としている。
【００２３】
【発明の概要】
本発明に係る防汚塗料組成物は、重合性不飽和カルボン酸のトリアルキルシリルエステルから誘導される成分単位を２０〜６５重量％の量で有し数平均分子量が３０００〜２００００、重量平均分子量が４０００〜１５００００、ガラス転移点が２５〜８０℃、５０％キシレン溶液における粘度（２５℃、ＣＰＳ）が４０〜１０００の被膜形成性共重合体と、酸化亜鉛と、上記被膜形成性共重合体と相溶可能な数平均分子量が１０００〜１０００００の（メタ）アクリル酸エステル系重合体とを含んでなり、
上記被膜形成性共重合体１００重量部に対して、上記酸化亜鉛が１〜１０００重量部の量で含有され、上記（メタ）アクリル酸エステル系重合体が５〜２００重量部の量で含有されていることを特徴としている。
その好ましい態様においては、酸化亜鉛を、該被膜形成性共重合体１００重量部に対して、通常１〜１０００重量部の量で、好ましくは３〜５００重量部の量で含有していることが望ましい。
【００２４】
本発明に係る防汚塗料組成物には、上記被膜形成性共重合体と酸化亜鉛とに加えて塩素化パラフィンを含んでいてもよく、このような防汚塗料組成物では、上記被膜形成性共重合体１００重量部に対して、酸化亜鉛が上記のような量で含有され、塩素化パラフィンが、１８〜６５重量部、好ましくは２０〜５５重量部の量で含有されていることが望ましい。
【００２５】
本発明の好ましい態様においては、上記トリアルキルシリルエステルの珪素原子に結合している３つのアルキル基のうちの少なくとも１つが炭素数３以上のものであることが望ましく、さらには、この３つのアルキル基の炭素原子数がすべて４以上であるものが好ましく、特に上記トリアルキルシリルエステルがトリブチルシリル（メタ）アクリレートであることが望ましい。また、上記塩素化パラフィンの平均炭素数は８〜３０であり、塩素含有率は３５〜７５％であることが望ましい。
【００２６】
本発明に係る防汚塗料組成物は、上記の被膜形成性共重合体と、酸化亜鉛とに加えて、上記被膜形成性共重合体と相溶可能な数平均分子量が１０００〜１０００００の（メタ）アクリル酸エステル系重合体を含んでいてもよく、このような防汚塗料組成物では、上記被膜形成性共重合体１００重量部に対して、酸化亜鉛が１〜１０００重量部、好ましくは３〜５００重量部の量で含有され、上記（メタ）アクリル酸エステル系重合体が５〜２００重量部、好ましくは１０〜２００重量部の量で含有されていることが望ましい。
【００２７】
また、このような防汚塗料組成物では、上記相溶可能な（メタ）アクリル酸エステル系重合体が、疎水性の（メタ）アクリル酸エステルの単独重合体、２種以上の（メタ）アクリル酸エステルの共重合体および（メタ）アクリル酸エステル・スチレン系共重合体からなる群から選ばれた少なくとも１種の（メタ）アクリル酸エステル系重合体であることが望ましく、さらには、これらの（メタ）アクリル酸エステル系重合体のガラス転移温度（Ｔｇ）は０℃以上であることが望ましい。
【００２８】
本発明に係る防汚塗料組成物は、上記の被膜形成性共重合体と、酸化亜鉛と、上記の（メタ）アクリル酸エステル系重合体とに加えて、さらに塩素化パラフィンを含んでいてもよく、このような防汚塗料組成物では、上記被膜形成性共重合体１００重量部に対して、酸化亜鉛が１〜１０００重量部好ましくは３〜５００重量部の量で含有され、（メタ）アクリル酸エステル系重合体が５〜２００重量部、好ましくは１０〜２００重量部の量で含有され、上記塩素化パラフィンが５〜１５０重量部、好ましくは８〜１００重量部の量で含有されていることが望ましい。
【００２９】
本発明に係る防汚塗料組成物は、上記被膜形成性共重合体と酸化亜鉛とに加えて、脱水剤を含んでいてもよく、このような防汚塗料組成物では、上記被膜形成性共重合体１００重量部に対して、酸化亜鉛が１〜１０００重量部好ましくは３〜５００重量部の量で含有され、上記脱水剤は０．１〜２００重量部、好ましくは１〜１００重量部の量で含有されていることが望ましい。
【００３０】
本発明に係る防汚塗料組成物は、上記被膜形成性共重合体と酸化亜鉛と塩素化パラフィンと脱水剤とを含んでいてもよく、このような防汚塗料組成物では、上記被膜形成性共重合体１００重量部に対して、酸化亜鉛が１〜１０００重量部好ましくは３〜５００重量部の量で含有され、塩素化パラフィンは３〜２００重量部、好ましくは５〜１５０重量部、さらに好ましくは１８〜６５重量部の量で含有され、上記脱水剤は０．１〜２００重量部、好ましくは１〜１００重量部の量で含有されていることが望ましい。
【００３１】
本発明に係る防汚塗料組成物は、上記被膜形成性共重合体と酸化亜鉛と塩素化パラフィンと上記（メタ）アクリル酸エステル系重合体と脱水剤とを含んでいてもよく、このような防汚塗料組成物では、上記被膜形成性共重合体１００重量部に対して、酸化亜鉛は１〜１０００重量部、好ましくは３〜５００重量部の量で含有され、
塩素化パラフィンは３〜２００重量部、好ましくは５〜１５０重量部の量で含有され、
上記（メタ）アクリル酸エステル系重合体は１〜２００重量部、好ましくは５〜２００重量部、特に好ましくは１０〜２００重量部の量で含有され、
上記脱水剤は０．１〜２００重量部、好ましくは１〜１００重量部の量で含有されていることが望ましい。
【００３２】
本発明に係る上記何れの防汚塗料組成物においても、有機系および／または無機系の防汚剤（酸化亜鉛を除く）を、例えば、被膜形成性共重合体１００重量部に対して５０〜１５００重量部程度の量で含有することが好ましく、このような防汚剤（殺生物剤）のうちでも、銅または銅化合物（例：亜酸化銅）、ジンクピリチオンなどが好ましい。
【００３３】
本発明に係る防汚塗料組成物のうちで、上記被膜形成性共重合体と酸化亜鉛とに加えて、塩素化パラフィン、上記（メタ）アクリル酸エステル系重合体、脱水剤あるいは防汚剤（酸化亜鉛を除く）などを含有するものは、上記効果に加えて水中での耐クラック性、防汚性、自己研磨性（消耗性）などにも優れた塗膜を形成でき、しかも貯蔵安定性に優れている。（なお、本明細書中では、特にその趣旨に反しない限り、「耐クラック性、耐剥離性」なる語は、水中、（乾燥）空気中両者を含む意味で用いる。）
本発明に係る防汚塗膜は、上記防汚塗料組成物から形成されている。
【００３４】
本発明に係る船体または水中構造物の防汚方法は、上記防汚塗料組成物を用いることを特徴としている。
本発明に係る防汚塗膜被覆船体または水中構造物は、上記の防汚塗料組成物からなる塗膜にて船体または水中構造物の表面が被覆されていることを特徴としている。
【００３５】
上記のような本発明に係る一液タイプの防汚塗料組成物によれば、耐クラック性、耐剥離性、特に空気中に晒されるなど乾燥下における耐クラック性、耐剥離性に優れ、しかも経時変化の安定性（すなわち、喫水線の変動などにより繰返して乾燥下に晒されたり、水中に浸漬されたりすることによっても経時変化しにくく、長期安定性を有すること）に優れた塗膜を形成できる。
【００３６】
特に、上記被膜形成性共重合体と酸化亜鉛とに加えて、さらに上記塩素化パラフィン、（メタ）アクリル酸エステル系重合体、脱水剤、防汚剤（酸化亜鉛を除く）などを含有する本発明の防汚塗料組成物では、上記効果に加えて、さらに船底などの基材あるいはプライマー層などに対する耐剥離性などの物性に優れ、防汚性、自己研磨性（消耗性）にも優れているような防汚塗膜を形成でき、しかも貯蔵安定性に優れている。
【００３７】
【発明の具体的説明】
以下、本発明に係る防汚塗料組成物について、具体的に説明する。
本発明に係る防汚塗料組成物は、下記のような被膜形成性共重合体と、酸化亜鉛とを含有しており、酸化亜鉛は、この被膜形成性共重合体１００重量部に対して、通常１〜１０００重量部、好ましくは３〜５００重量部の量で含有されている。このような本発明に係る一液タイプの防汚塗料組成物によれば、耐クラック性、耐剥離性特に空気中に晒されるなど乾燥下における耐クラック性、耐剥離性に優れ、しかも経時変化の安定性（すなわち、船体、水中構造物等の防汚塗膜が喫水線の変動などにより繰返して乾燥下に晒されたり、水中に浸漬されたりすることによっても経時変化しにくく、長期安定性を有すること）に優れた塗膜を形成できる。なお、この酸化亜鉛量が１重量部未満では、例えば塗膜が空気中に晒されるなど乾燥条件下におかれた際に、簡単にクラックや剥離が生じてしまい、また、１０００重量部を超える量では、それ以上の効果の向上は望めず、顔料濃度が高すぎることにより生ずる塗布、乾燥時のワレの発生や、スプレー塗装時のダスト量の増加をまねく傾向がある。
【００３８】
［被膜形成性共重合体］
上記の被膜形成性共重合体は、重合性不飽和カルボン酸のトリアルキルシリルエステルから誘導される成分単位を２０〜６５重量％の量で有し数平均分子量が３０００〜５００００である。
【００３９】
このトリアルキルシリルエステルは、例えば、下記式［I］：
【００４０】
【化３】

【００４１】
で表される。この式［I］中、Ｒ¹は、水素原子またはメチル基等のアルキル基を表し、Ｒ²、Ｒ³およびＲ⁴は、メチル基、エチル基、プロピル基、ブチル基等の炭素数が１〜１８個程度のアルキル基を表し、Ｒ²、Ｒ³およびＲ⁴は互いに異なっていてもよく同一であってもよい。このようなトリアルキルシリルエステルとしては、具体的には、例えば、（メタ）アクリル酸トリメチルシリルエステル、（メタ）アクリル酸トリエチルシリルエステル、（メタ）アクリル酸トリプロピルシリルエステル、（メタ）アクリル酸トリブチルシリルエステル等のようにＲ²、Ｒ³およびＲ⁴が同一のトリアルキルシリルエステル、
（メタ）アクリル酸ジメチルプロピルシリルエステル、（メタ）アクリル酸モノメチルジプロピルシリルエステル、（メタ）アクリル酸メチルエチルプロピルシリルエステル等のようにＲ²、Ｒ³およびＲ⁴のうちの１部または全部が互いに異なったトリアルキルシリルエステルなどが挙げられる。本発明においては、このようなトリアルキルシリルエステルを１種単独で用いてもよく、また２種以上組み合わせて用いてもよい。このようなトリアルキルシリルエステルの内では、Ｒ²、Ｒ³およびＲ⁴のうちの少なくとも１つのアルキル基の炭素数が３以上であるものが好ましく、さらにはこの３つのアルキル基の炭素原子数がすべて４以上であるものが好ましく、またＲ²、Ｒ³およびＲ⁴の総炭素数が５〜２１程度のものが好ましい。このようなトリアルキルシリルエステルのうちでは、特にトリアルキルシリルエステル合成の容易性、あるいはこのようなトリアルキルシリルエステルを用いてなる防汚塗料組成物の造膜性、貯蔵安定性、研掃性の制御のしやすさなどを考慮すると、（メタ）アクリル酸トリブチルシリルエステルが最も好ましく用いられる。
【００４２】
このようなトリアルキルシリルエステルと共重合されるモノマー（コモノマー）としては、任意の重合性不飽和化合物（エチレン性不飽和単量体）を用いることができ、このような重合性不飽和化合物としては、具体的には、例えば、（メタ）アクリル酸メチルエステル、（メタ）アクリル酸エチルエステル、（メタ）アクリル酸２−エチルヘキシルエステル、（メタ）アクリル酸シクロヘキシルエステル等の（メタ）アクリル酸アルキルエステル、スチレン、α-メチルスチレン等のスチレン類、酢酸ビニル、プロピオン酸ビニル等のビニルエステル類などを挙げることができ、好ましくは、メタアクリル酸メチルエステル（ＭＭＡ）が用いられる。このようなＭＭＡは、コモノマー（エチレン性不飽和単量体）中に、通常、３０重量％以上、好ましくは、５０重量％以上の量で含まれていることが好ましく、このような量でＭＭＡを含有してなる共重合体では、ガラス転移温度（Ｔｇ）が、例えば３０〜６０℃と高く、後述するような塩素化パラフィンが配合されてなる防汚塗料組成物からなる塗膜の強度が低下されない。
【００４３】
この（メタ）アクリル酸アルキルエステル等のような重合性不飽和化合物から誘導される成分単位とトリアルキルシリルエステルから誘導される成分単位とは、共重合体中においては、原料として用いられた各モノマーのエチレン結合が解裂して通常ランダムに結合している。
【００４４】
なお、このような共重合体中にカルボン酸残基が存在していると、得られる防汚塗料組成物の貯蔵安定性を著しく低下させるため、該共重合体中には、カルボン酸残基が存在しないことが望ましい。該共重合体の合成時には、カルボン酸残基を有しない高純度のモノマーを用いることが好ましい。
【００４５】
このような皮膜形成性共重合体中には、上述したように１種または２種以上の上記のような重合性不飽和カルボン酸のトリアルキルシリルエステルから誘導される成分単位（トリアルキルシリルエステル成分単位）が含まれていてもよいが、このようなトリアルキルシリルエステル成分単位は、その合計量として２０〜６５重量％の量で、好ましくは３０〜５５重量％の量で該共重合体中に含有されていると、この防汚塗料組成物から長期防汚性に優れた防汚塗膜が得られるため好ましい。また、この共重合体のＧＰＣ測定による数平均分子量（Ｍｎ）は、３０００〜５００００、好ましくは３０００〜２００００、さらに好ましくは４０００〜１５０００、特に好ましくは５０００〜１２０００であり、また重量平均分子量（Ｍｗ）は、通常４０００〜１５００００（１５万）、好ましくは４０００〜６００００（６万）、さらに好ましくは６０００〜３００００（３万）であることが望ましく、またこの共重合体の分子量分布（Ｍｗ／Ｍｎ）は、通常１．０〜４．０、好ましくは１．０〜３．０、特に好ましくは１．０〜２．５であることが望ましく、またこの共重合体のガラス転移温度（Ｔｇ℃）は、通常１５〜８０℃、好ましくは２５〜８０℃、さらに好ましくは３０〜７０℃、特に好ましくは３５〜６０℃であることが望ましく、また、この共重合体の例えば５０％キシレン溶液における粘度（２５℃、ＣＰＳ）は、通常３０〜１０００、好ましくは４０〜６００であることが望ましい。
【００４６】
この共重合体の数平均分子量が上記範囲（１０００〜５００００）内にあると、長期間の塗膜防汚性能、形成された塗膜の耐ダメージ性（耐衝撃性）および得られる塗料組成物の貯蔵安定性と塗膜の耐クラック性に優れるようになる。
【００４７】
このような被膜形成性共重合体として、具体的には、下記のようなものが挙げられ、好ましくは付番▲１▼、▲２▼、さらに好ましくは付番▲１▼に示す被膜形成性共重合体が用いられる。
▲１▼： トリブチルシリルメタクリレート(イ)と、メチルメタクリレート（MMA）との共重合体であって、その共重合比（(イ)／(MMA)：重量比）が３５〜６５／６５〜３５（全成分合計１００重量部）であり、数平均分子量（Ｍｎ）が３０００〜５万、好ましくは５０００〜１２０００であり、重量平均分子量（Ｍｗ）が４０００〜１５万、好ましくは６０００〜３００００（３万）であり、分子量分布（Ｍｗ／Ｍｎ）が、１．０〜４．０、好ましくは１．０〜２．５であり、ガラス転移温度（Ｔｇ℃）が３０〜７０℃、好ましくは３５〜６０℃であり、その例えば５０％キシレン溶液における粘度（２５℃、ＣＰＳ）が、３０〜１０００、好ましくは４０〜６００のもの、
▲２▼： トリプロピルシリルメタクリレート(ロ)とメチルメタクリレート（MMA）と２-エチルヘキシルアクリレート（ハ）との共重合体であって、その共重合比（(ロ)／(MMA)／(ハ)：重量比）が２５〜５５／７４〜３５／１〜１０（全成分合計１００重量部）であり、数平均分子量（Ｍｎ）が３０００〜５万、好ましくは５０００〜１２０００であり、重量平均分子量（Ｍｗ）が４０００〜１５万、好ましくは６０００〜３００００（３万）であり、分子量分布（Ｍｗ／Ｍｎ）が、１．０〜４．０、好ましくは１．０〜２．５であり、ガラス転移温度（Ｔｇ℃）が３０〜７０℃、好ましくは３５〜６０℃であり、例えば５０％キシレン溶液におけるその粘度（２５℃、ＣＰＳ）が、３０〜１５００、好ましくは４０〜１０００のもの、
▲３▼： トリブチルシリルメタクリレート(イ)と、トリプロピルシリルメタクリレート(ロ)と、メチルメタクリレート（MMA）との共重合体であって、その共重合比（(イ)／(ロ)／(MMA)：重量比）が３０〜６０／１〜２０／６９〜２０（全成分合計１００重量部）であり、数平均分子量（Ｍｎ）が３０００〜５万、好ましくは５０００〜１２０００であり、重量平均分子量（Ｍｗ）が４０００〜１５万、好ましくは６０００〜３００００（３万）であり、分子量分布（Ｍｗ／Ｍｎ）が、１．０〜４．０、好ましくは１．０〜２．５であり、ガラス転移温度（Ｔｇ℃）が３０〜６０℃、好ましくは３５〜５５℃であり、例えば５０％キシレン溶液におけるその粘度（２５℃、ＣＰＳ）が、３０〜１０００、好ましくは４０〜４００のもの、
▲４▼： トリブチルシリルメタクリレート(イ)と、トリプロピルシリルメタクリレート(ロ)と、メチルメタクリレート（MMA）と、２-エチルヘキシルアクリレート（ハ）との共重合体であって、その共重合比（(イ)／(ロ)／(MMA)／(ハ)：重量比）が３０〜６０／１〜２０／６８〜１９／１〜１０（全成分合計１００重量部）であり、数平均分子量（Ｍｎ）が３０００〜５万、好ましくは５０００〜１２０００であり、重量平均分子量（Ｍｗ）が４０００〜１５万、好ましくは６０００〜３００００（３万）であり、分子量分布（Ｍｗ／Ｍｎ）が、１．０〜４．０、好ましくは１．０〜２．５であり、ガラス転移温度（Ｔｇ℃）が３０〜６０℃、好ましくは３５〜５５℃であり、例えば５０％キシレン溶液におけるその粘度（２５℃、ＣＰＳ）が、３０〜１０００、好ましくは４０〜４００のもの、
▲５▼： トリブチルシリルメタクリレート(イ)と、メチルメタクリレート（MMA）と、２-エチルヘキシルアクリレート（ハ）との共重合体であって、その共重合比（(イ)／(MMA)／(ハ)：重量比）が３５〜６５／６４．９〜３４．９／０．１〜１０（全成分合計１００重量部）であり、数平均分子量（Ｍｎ）が３０００〜５万、好ましくは５０００〜１２０００であり、重量平均分子量（Ｍｗ）が４０００〜１５万、好ましくは６０００〜３００００（３万）であり、分子量分布（Ｍｗ／Ｍｎ）が、１．０〜４．０、好ましくは１．０〜２．５であり、ガラス転移温度（Ｔｇ℃）が３０〜７０℃、好ましくは３５〜６０℃であり、例えば５０％キシレン溶液におけるその粘度（２５℃、ＣＰＳ）が、３０〜１０００、好ましくは４０〜６００のもの、
▲６▼： トリイソプロピルシリルアクリレート(ニ)とメチルメタクリレート（MMA）とエチルアクリレート(ホ)との共重合体であって、その共重合比（(ニ)／(MMA)／(ホ)：重量比）が４０〜６５／５９〜２０／１〜２０（全成分合計１００重量部）であり、数平均分子量（Ｍｎ）が１０００〜５万、好ましくは３０００〜３００００（３万）であり、重量平均分子量（Ｍｗ）が１０００〜１５万、好ましくは３０００〜３万であり、分子量分布（Ｍｗ／Ｍｎ）が１．０〜４．０、好ましくは１．０〜３．０であり、ガラス転移温度（Ｔｇ℃）が２０〜８０℃、好ましくは２５〜７５℃であり、例えば５０％キシレン溶液におけるその粘度（２５℃、ＣＰＳ）が３０〜１５００、好ましくは４０〜１３００のもの、
▲７▼： トリイソブチルシリルメタクリレート(ヘ)とメチルメタクリレート（MMA）と、２-エチルヘキシルアクリレート（ハ）との共重合体であって、その共重合比（(ヘ)／(MMA)／(ハ)：重量比）が３５〜６５／６４．９〜３４．９／０．１〜１０（全成分合計１００重量部）であり、数平均分子量（Ｍｎ）が１０００〜５万、好ましくは３０００〜１２０００であり、重量平均分子量（Ｍｗ）が１０００〜１５万、好ましくは３０００〜３００００（３万）であり、分子量分布（Ｍｗ／Ｍｎ）が１．０〜４．０、好ましくは１．０〜２．５であり、ガラス転移温度（Ｔｇ℃）が２５〜８０℃、好ましくは３０〜７０℃であり、例えば５０％キシレン溶液におけるその粘度（２５℃、ＣＰＳ）が、３０〜２０００、好ましくは４０〜１５００のもの、
など。
【００４８】
このような被膜形成性共重合体を調製するには、例えば、通常窒素気流中などの不活性雰囲気下、キシレン等の有機溶媒中で、トリブチルシリルメタクリレート等のトリアルキルシリルエステルと、コモノマー類中にメチルメタクリレートが５０重量％以上（例：８０重量％）の量で含有された重合性不飽和化合物とを、２，２’−アゾビスイソブチロニトリル等のアゾ系あるいは過酸化物系などの重合開始剤、必要に応じてｎ−オクチルメルカプタンなどの重合調整剤などの存在下に、２〜１２時間程度、５０〜１２０℃程度の温度でラジカル重合等の方法にて反応させればよい。
【００４９】
このようにして得られた被膜形成性共重合体には、用いられた各モノマー量に対応する量で各成分単位が含まれている。
なお重合方法は、簡便な上記ラジカル溶液重合法に限定されず、従来より公知の種々の方法を採用することができる。また溶媒としては、上記芳香族（例：キシレン）の他、脂肪族、ケトン、エステル、エーテルなど通常塗料用として汎用されている各種溶剤から任意に選択することができる。溶媒としては、特に水分含有量の低い溶媒が好ましく、このような低水分溶媒を用いると、上記反応時及びその後の加水分解反応を避けることができるため好ましい。なお、アルコール系溶媒は、初期水分含量が高く、しかもシラノールとの反応性を有するため、かかる観点からは上記反応時に用いるのは適当ではない。
【００５０】
［防汚塗料組成物の製造］
このような防汚塗料組成物は、従来より公知の方法を適宜利用することにより製造することができ、例えば、上記被膜形成性共重合体と、該被膜形成性共重合体１００重量部に対して１〜１０００重量部の量の酸化亜鉛と、必要により用いられる後述するような１８〜６５重量部の量の塩素化パラフィンと、５０〜１５００重量部の量の防汚剤（例：亜酸化銅８０〜１２００重量部）と、０．１〜２００重量部の量の脱水剤（例：無水石膏、モレキュラーシーブ）と、任意量のタレ止め・沈降防止剤、顔料、溶剤などとを一度にあるいは任意の順序で加えて攪拌・混合・分散すればよい。
【００５１】
このような本発明に係る防汚塗料組成物は、被膜形成性共重合体と酸化亜鉛（亜鉛華）とを含有しているが、この他に塩素化パラフィン、防汚剤、後述するような（メタ）アクリル酸エステル系重合体、脱水剤、タレ止め・沈降防止剤、鱗片状顔料、溶剤などを含んでいてもよい。
【００５２】
［塩素化パラフィン］
すなわち、本発明の好ましい態様においては、上記防汚塗料組成物には、上記被膜形成性共重合体と酸化亜鉛に加えて、さらに塩素化パラフィン（塩化パラフィン；塩パラ）が含まれていてもよい。このような防汚塗料組成物では、上記被膜形成性共重合体１００重量部に対して、酸化亜鉛は通常、１〜１０００重量部、好ましくは３〜５００重量部の量で含有され、塩素化パラフィンは、１８〜６５重量部、好ましくは２０〜５５重量部の量で含有されていることが望ましい。また、このような防汚塗料組成物では、上記被膜形成性共重合体１００重量部に対して、後述するような防汚剤は、通常５０〜１５００重量部、好ましくは８０〜１２００重量部の量で含有されていることが望ましい。
【００５３】
塩素化パラフィンは、得られる防汚塗料組成物からなる塗膜（本明細書中では、「防汚塗膜」とも言う）の耐クラック性特に水中（淡水、海水を含む。以下同じ）に浸漬するような場合での耐クラック性の向上に寄与するが、このような塩素化パラフィンとしては、直鎖状でもよく分岐を有していてもよく、室温で液状でも固体（粉体）でもよいが、その平均炭素数が通常、８〜３０、好ましくは１０〜２６のものが好ましく用いられ、その数平均分子量が通常、２００〜１２００、好ましくは３００〜１１００であり、粘度が通常１以上（ポイズ／２５℃）、好ましくは１．２以上（ポイズ／２５℃）であり、その比重が１．０５〜１．８０／２５℃、好ましくは１．１０〜１．７０／２５℃のものが好ましく用いられる。このような炭素数の塩素化パラフィンを用いると、得られる防汚塗料組成物を用いて割れ（クラック）、剥がれの少ない塗膜を形成できる。なお塩素化パラフィンの炭素数は、クラックの抑制効果および得られる塗膜表面の消耗性（更新性）と防汚性から８〜３０の範囲にあることが好ましい。また、この塩素化パラフィンの塩素化率（塩素含有量：重量％）は、通常３５〜７５％、好ましくは３５〜６５％であることが好ましい。このような塩素化率の塩素化パラフィンを用いると、得られる防汚塗料組成物を用いて割れ（クラック）、剥がれの少ない塗膜を形成できる。なお塩素化パラフィンの塩素化率が、３５〜７５％の範囲にあると、被膜形成性共重合体（シリルエステル共重合体）との混和性（相溶性）、クラックの抑制効果、得られた塗膜表面の消耗性および防汚性に優れるようになる。このような塩素化パラフィンとしては、東ソー（株）製の「トヨパラックス150」、「トヨパラックスA-70」などが挙げられる。本発明においては、このような塩素含有率、炭素数などの異なる２種以上の塩素化パラフィンを適宜組み合わせて用いることができる。このように２種以上の塩素化パラフィンを組み合わせて用いる場合には、上記塩素化パラフィンの炭素数、塩素化率は、防汚塗料組成物中に含まれるこれらの塩素化パラフィンの炭素数あるいは塩素化率の平均値で示す。
【００５４】
このような塩素化パラフィンは、本発明に係る防汚塗料組成物においては、上記の被膜形成性共重合体１００重量部に対して、３〜２００重量部、好ましくは５〜１５０重量部、さらに好ましくは１８〜６５重量部、より好ましくは２０〜５５重量部、特に好ましくは２０〜５０重量部の量で含まれていることが好ましい。この塩素化パラフィンの量が１８〜６５重量部の範囲にあると、該防汚塗料組成物にて形成された塗膜に生ずるクラックの抑制効果に優れかつ塗膜強度および耐ダメージ（衝撃）性に優れるようになる。
【００５５】
このように上記被膜形成性共重合体と酸化亜鉛とに加えて上記のように塩素化パラフィン等が配合された防汚塗料組成物は、１液性で貯蔵安定性に優れ、しかも、例えば、船底に塗布形成されたこの防汚塗料組成物からなる塗膜（防汚塗膜）が空気中に晒され、また没水しても、防汚塗膜のクラックは抑制される。また、該防汚塗料組成物がプライマー表面に塗布される場合、塗布されたプライマー表面からの防汚塗膜の剥離は抑制される。また、本発明の防汚塗料組成物による塗装を含む各種防汚塗料による船底等の塗装を複数回行ない、あるいは本発明の防汚塗料組成物を用いて、既に本発明の防汚塗膜が形成されている船底等の表面に修繕塗装等を行う場合においては、前回塗布形成された防汚塗膜表面からの本発明の表面防汚塗膜の剥離は抑制される。しかも、このようにプライマー表面にあるいは修繕すべき船底等の表面に塗布形成された本発明の防汚塗膜では、その消耗制御が可能であり、用いられる環境に応じて必要な消耗度と防汚力（性）を提供することができる。従って、この防汚塗料組成物では、用途に応じて形成すべき防汚塗膜の膜厚を最大限低減化することができるため、経済的にも優れている。
【００５６】
［防汚剤］
本発明に係る防汚塗料組成物には、必ずしも防汚剤が含有されていなくともよいが、防汚剤が含有されていることが好ましい。
【００５７】
このような防汚剤としては、有機系のものであってもよく無機系のもの（酸化亜鉛を除く）であってもよく、特に限定されないが、具体的には、例えば、亜酸化銅（Ｃｕ₂Ｏ）、銅粉、チオシアン化第１銅（ロダン銅）、等の銅または銅化合物の他、下記式［II］で示される金属−ピリチオンおよびその誘導体［式中Ｒ¹〜Ｒ⁴は、それぞれ独立に水素、アルキル基、アルコキシ基、ハロゲン化アルキル基を示し、Ｍは、Ｚｎ、Ｃｕ、Ｎａ、Ｍｇ、Ｃａ、Ｂａ、Ｐｂ、Ｆｅ、Ａｌ等の金属を示し、ｎは価数を示す］：
【００５８】
【化４】

【００５９】
、テトラメチルチウラムジサルファイド、カーバメート系の毒物（例：ジンクジメチルジチオカーバメート、マンガン-２-エチレンビスジチオカーバメート）、２，４，５，６−テトラクロロイソフタロニトリル、Ｎ，Ｎ−ジメチルジクロロフェニル尿素、４，５−ジクロロ-２-ｎ-オクチル-４-イソチアゾリン-３-オン、２，４，６−トリクロロフェニルマレイミド、ピリジントリフェニルボラン・ロダン銅等を挙げることができ、好ましくは亜酸化銅が用いられる。亜酸化銅以外の防汚剤は、亜酸化銅と併用して用いることが好ましく、この亜酸化銅と併用される防汚剤としては、２-ピリジンチオール-１-オキシド亜鉛塩（ジンクピリチオン）が好ましい。
【００６０】
このような防汚剤は１種または２種以上組み合わせて用いることができる。
このような防汚剤は、防汚塗料組成物調製時に用いられる防汚剤、被膜形成性共重合体などの種類あるいはこのような防汚塗料組成物が塗布形成される船舶等の種類（船舶では、外航−内航用、各種海水域用、木造−鋼鉄−アルミ製船用等）などにもより一概に決定されないが、上記被膜形成性共重合体１００重量部に対して、防汚剤総量として通常５０〜１５００重量部の量で、好ましくは８０〜１２００重量部の量で用いられる。
【００６１】
例えば、防汚剤として上記亜酸化銅を用いる場合、この亜酸化銅は、上記被膜形成性共重合体１００重量部に対して通常、８０〜１２００重量部程度の量で防汚塗料組成物中に含有されていてもよい。
【００６２】
［（メタ）アクリル酸エステル系重合体］
本発明に係る防汚塗料組成物には、上記上記被膜形成性共重合体と酸化亜鉛とに加えて、この被膜形成性共重合体と相溶可能な数平均分子量が１０００〜１０００００（１０万）の（メタ）アクリル酸エステル系重合体［（メタ）アクリル酸シリルエステル以外の（メタ）アクリル酸系エステルの単独重合体または共重合体］が含有されていてもよい。
【００６３】
本発明の防汚塗料組成物においては、上記被膜形成性共重合体と酸化亜鉛と上記塩素化パラフィンとに加えて、この被膜形成性共重合体と相溶可能な（メタ）アクリル酸エステル系重合体が配合されていると、得られる塗膜の耐クラック性を一層改善することができ、塗膜の海水消耗速度と防汚性能の持続性を好適な範囲に調整することができ、また既存の防汚塗膜の上に本発明の防汚塗料組成物を上塗りする場合には得られる塗膜の接着性を一層改善する効果を発揮することができるという利点があり、また、上記塩素化パラフィンの配合量を低減しても、得られる塗膜の耐クラック性を改善することができるという利点がある。
【００６４】
このような被膜形成性共重合体と相溶可能な（メタ）アクリル酸エステル系重合体としては、前記被膜形成性共重合体調製用として用いられる（メタ）アクリル酸シリルエステル以外の（メタ）アクリル酸系エステルの単独重合体または共重合体が挙げられ、（メタ）アクリル酸エステルの単独重合体、少なくとも２種以上の（メタ）アクリル酸エステルの共重合体、（メタ）アクリル酸エステル・スチレン系共重合体などが挙げられる。このような（メタ）アクリル酸エステル系重合体は、１種または２種以上組み合わせて用いることができる。
【００６５】
これらの（メタ）アクリル酸エステル系重合体は、被膜形成性共重合体と相溶可能である限り、例えば鎖状であっても分岐状であってもよく、また架橋構造を有していてもよい。
【００６６】
ここで、被膜形成性共重合体と「相溶可能」な（メタ）アクリル酸エステル系重合体とは、被膜形成性共重合体（トリアルキルシリル（メタ）アクリレート共重合体ともいう）濃度３０重量％のキシレン溶液と、（メタ）アクリル酸エステル系重合体濃度３０重量％のキシレン溶液とを、１：１の容量比で２５℃において混合したとき、透明な均一溶液となるか、または２液分液層を形成することなく乳白色の均一溶液を形成するような（メタ）アクリル酸エステル系重合体をいう。
【００６７】
なお、（メタ）アクリル酸エステル系重合体の数平均分子量が上記のような範囲内にあると、クラックの抑制と、消耗度の調整を効果的に行うことができる上に、静置防汚性にも優れた防汚塗膜を形成できる傾向がある。また（メタ）アクリル酸エステル系重合体の数平均分子量が、上記範囲を超えて大きくなると得られる防汚塗膜のクラックの抑制効果は大きく、消耗度の低減効果も大きいが、静置防汚性は低下する傾向があり、また上記（メタ）アクリル酸エステル系重合体の分子量が上記範囲を超えて小さくなると、得られる防汚塗膜の防汚性を高く維持できても、クラックの抑制効果は低減する傾向がある。
【００６８】
このような（メタ）アクリル酸エステル系重合体としては、例えば、（メタ）アクリル酸メチル、（メタ）アクリル酸ブチル、（メタ）アクリル酸イソブチル、（メタ）アクリル酸ｔ−ブチル、（メタ）アクリル酸シクロヘキシル、（メタ）アクリル酸フェニル等の（メタ）アクリル酸エステルの単独重合体あるいはこれらのモノマーの共重合体、
スチレン(ST)等の芳香族ビニル化合物、酢酸ビニル、塩化ビニル、エチレン、プロピレン、ブタジエン、ビニルエーテル化合物などの各種モノマーと（メタ）アクリル酸エステル系モノマーの共重合体を挙げることができる。
【００６９】
このような（メタ）アクリル酸エステル系重合体として、具体的には、例えば、
▲１▼：メタアクリル酸メチル(MMA)とメタアクリル酸ブチル(BMA)との共重合体であって、その共重合比（各成分の重量比で示す。以下同様）（MMA／BMA）が３０〜７０／７０〜３０（全成分合計１００重量部）であり、数平均分子量が１０００〜１０万、好ましくは１０００〜５万のもの、
▲２▼：メタアクリル酸イソブチル(i-BMA)とメタアクリル酸ｔ−ブチル(t-BMA)とスチレン(ST)とメタアクリル酸ステアリル(SLMA)との共重合体であって、その共重合比（i-BMA／t-BMA／ST／SLMA）が１０〜４０／１０〜４０／２０〜６０／５〜２０（全成分合計１００重量部）であり、数平均分子量が１０００〜１０万、好ましくは１０００〜８万程度のもの、
▲３▼：メタアクリル酸メチル（MMA）の単独重合体であって、数平均分子量が１０００〜１０万、好ましくは１０００〜２万程度のもの、
▲４▼：メタアクリル酸エチル（EMA）の単独重合体であって、数平均分子量が１０００〜１０万、好ましくは１０００〜２万程度のもの、
▲５▼：メタアクリル酸メチル（MMA）とアクリル酸ブチル（BA）の共重合体であって、その共重合比（MMA／BA）が９０〜１０／１０〜９０（全成分合計１００重量部）であり、数平均分子量が１０００〜１０万、好ましくは１０００〜５万程度のもの、
▲６▼：メタアクリル酸エチル（EMA）とアクリル酸ブチル（BA）の共重合体であって、その共重合比（EMA／BA）が１００〜７０／０〜３０（全成分合計１００重量部）であり、数平均分子量が１０００〜１０万、好ましくは１０００〜３万程度のもの、
などを挙げることができる。
【００７０】
このような（メタ）アクリル酸エステル系重合体のうちでは、
好ましくは疎水性のアクリル系ポリマー［（メタ）アクリル酸エステル含量が５０重量％を超え、スチレン含量が５０重量％未満のもの］、またはスチレン系ポリマー［スチレン含量が５０重量％以上のもの］が用いられ、付番▲１▼、▲２▼の（メタ）アクリル酸エステル系重合体が特に好ましく用いられる。
【００７１】
このような（メタ）アクリル酸エステル系重合体のガラス転移温度（Ｔｇ）は０℃以上であることが好ましく、特に２０〜１０５℃であることが好ましい。なお、ガラス転移温度（Ｔｇ）の低い（メタ）アクリル酸エステル系重合体（例：アクリル酸ブチル(BA)ホモポリマー）では、得られる防汚塗膜におけるクラックの抑制効果が低くなることがある。
【００７２】
なお、このような（メタ）アクリル酸エステル系重合体は、塩素化パラフィンが含有されない被膜形成性共重合体含有防汚塗料組成物では、該被膜形成性共重合体１００重量部に対して通常１０〜２００重量部の量で用いられるが、この塩素化パラフィンが含有される防汚塗料組成物ではさらに低減可能であり、該被膜形成性共重合体１００重量部に対して５〜２００重量部の量で用いることができる。
【００７３】
すなわち、このような防汚塗料組成物では、酸化亜鉛は、前記被膜形成性共重合体１００重量部に対して、１〜１０００重量部、好ましくは３〜５００重量部の量で含有され、
上記（メタ）アクリル酸エステル系重合体は、通常１〜２００重量部、好ましくは５〜２００重量部、さらに好ましくは１０〜２００重量部、特に好ましくは１５〜１６０重量部の量で含有され、
上記塩素化パラフィンは、通常３〜２００重量部、好ましくは５〜１５０重量部、さらに好ましくは８〜１００重量部の量で含有されていることが望ましい。また、このような防汚塗料組成物では、前記被膜形成性共重合体１００重量部に対して、防汚剤は、通常１００〜２０００重量部、好ましくは１５０〜１５００重量部の量で含有されていることが望ましい。上記塩素化パラフィン含量が５〜１５０重量部の範囲にあると、とくに得られる防汚塗膜のクラックの抑制効果および得られる防汚塗膜の機械的強度に優れるようになる。
【００７４】
なお、このような（メタ）アクリル酸エステル系重合体中には、前記被膜形成性共重合体の場合と同様、カルボン酸残基が存在していると、得られる防汚塗料組成物の貯蔵安定性を著しく低下させるため、該（メタ）アクリル酸エステル系重合体中には、カルボン酸残基が存在しないことが望ましく、ポリマーの酸価（ＡＶ値）は通常１５以下、さらに好ましくは１０以下、特に好ましくは５以下となるように、カルボン酸残基を有しないモノマーを用いることが好ましい。
【００７５】
この防汚塗料組成物では、例えば、船底に塗布形成されたこの防汚塗料組成物からなる塗膜（防汚塗膜）が没水しても、防汚塗膜のクラックは抑制され、消耗制御は可能であり、用いられる環境に応じて必要な消耗度と防汚性能を提供することができる。従って、このように（メタ）アクリル酸エステル系重合体が含有されている防汚塗料組成物では、用途に応じて防汚塗膜の膜厚を最大限低減化することができるために、経済的にも優れている。
【００７６】
［鱗片状顔料］
本発明に係る防汚塗料組成物には、上記の被膜形成性共重合体と上記の酸化亜鉛と上記の塩素化パラフィンとに加えて、下記のような鱗片状顔料が含有されていてもよい。
【００７７】
鱗片状顔料としては、雲母粉、鱗片状のアルミ粉、銅粉、亜鉛末あるいはパール顔料などが挙げられ、雲母粉が好ましく用いられる。
このような雲母粉の原石として、さらに具体的には、シロウンモ、ベニウンモ、ソーダウンモ、セリサイト、バナジンウンモ、イライトなどのシロウンモ系列、
クロウンモ、キンウンモ、テツウンモ、チンワルドウンモなどのクロウンモ系列の他、
カイリョク石、セラドン石などが挙げられるが、一般的には、シロウンモの粉砕物が用いられる。
【００７８】
このような鱗片状顔料の平均粒径、アスペクト比などは通常特に限定されないが、好ましくは、その平均粒径が０．１〜２００μｍであり、アスペクト比が（粒子の長辺／短辺の比）１０以上であることが望ましい。
【００７９】
このような防汚塗料組成物では、前記被膜形成性共重合体１００重量部に対して酸化亜鉛は１〜１０００重量部、好ましくは３〜５００重量部の量で含有され、上記塩素化パラフィンは通常５〜６５重量部、好ましくは８〜５５重量部の量で含有され、上記鱗片状顔料は通常１〜１００重量部、好ましくは５〜９０重量部の量で含有されていることが好ましい。またこのような防汚塗料組成物では、前記被膜形成性共重合体１００重量部に対して、防汚剤は、通常１００〜８００重量部、好ましくは２００〜６００重量部の量で含有されていることが望ましい。鱗片状顔料が１〜１００重量部の範囲にあると、添加効果に優れかつ防汚効果に優れ特に耐クラック性に優れた防汚塗膜を形成することができる。
【００８０】
なお、一般的に、鱗片状顔料を防汚塗料組成物などに配合すれば、得られる塗膜の耐クラック性の向上には効果的であると考えられる。しかしながら、従来の防汚塗料では、生理活性を有しない鱗片状顔料が配合された場合には、得られる防汚塗膜からの防汚剤の溶出は妨げられ、防汚効力は、大幅に低下してしまうとの問題点があった。ところが、本発明のような自己研磨性（消耗性）に優れたシリルエステル系防汚塗料組成物（ＡＦ）から形成される防汚塗膜では、海水中における表面更新性に優れており、塗膜表面に鱗片状顔料が存在していても充分な塗膜の更新性を有する上、もともと防汚活性も極めて高いレベルにあるため、防汚剤の過度の溶出を制御し適切な範囲に保持（制御）しつつ、しかも、没水後のクラックの発生をさらに効率的に抑制することができる。
【００８１】
なお、被膜形成性共重合体が（メタ）アクリル酸トリブチルシリルエステル［TBS(M)A］と（メタ）アクリル酸メチル［M(M)A］との共重合体である防汚塗料組成物からなる防汚塗膜を例に採って、さらに具体的に説明すると、海水中では、水酸イオン（ＯＨ^-）等の影響を受けて、該被膜形成性共重合体中のトリブチルシロキシ基（Ｂｕ₃ＳｉＯ−）が該共重合体主鎖に結合しているカルボニル基（−ＣＯ−）から切れて、トリブチルシラノール（Ｂｕ₃ＳｉＯＨ）となって海水中に溶解して行く。一方、主鎖を構成していたポリマーもカルボン酸塩の構造（−ＣＯＯ^-）で、海水中に脱落・溶解していくため防汚塗膜の海水との接面（防汚塗膜表面）は、次々と更新されるものと考えられる。このため、防汚塗膜中に含有されていた防汚剤は、速やかに防汚塗膜表面から放出される。ところが、上記のように鱗片状顔料が塗料中に含まれていると、海水と、防汚剤および被膜形成性共重合体との接触は抑制されるため、本発明では、上記のような効果が得られるのであろうと思われる。
【００８２】
本発明に係る防汚塗料組成物には、上記の被膜形成性共重合体と酸化亜鉛と塩素化パラフィンとに加えて、上記の（メタ）アクリル酸エステル系重合体と鱗片状顔料とが含有されていてもよい。
【００８３】
このような防汚塗料組成物では、前記被膜形成性共重合体１００重量部に対して、酸化亜鉛は１〜１０００重量部、好ましくは３〜５００重量部の量で含有され、
上記塩素化パラフィンは、通常３〜２００重量部、好ましくは５〜１００重量部、さらに好ましくは１０〜１００重量部の量で含有され、
上記（メタ）アクリル酸エステル系重合体は、通常１〜２００重量部、好ましくは５〜１００重量部、さらに好ましくは１０〜１００重量部の量で含有され、上記鱗片状顔料は通常０．５〜４００重量部、好ましくは１〜２００重量部、さらに好ましくは５〜１５０重量部の量で含有されていることが望ましい。また、このような防汚塗料組成物では、前記被膜形成性共重合体１００重量部に対して、防汚剤は、通常１００〜２０００重量部、好ましくは１５０〜１５００重量部の量で含有されていることが望ましい。
【００８４】
［脱水剤］
また、脱水剤が含有された防汚塗料組成物では、貯蔵安定性を一層向上させることができ、このような脱水剤としては、無水石膏（ＣａＳＯ₄）、合成ゼオライト系吸着剤（商品名：モレキュラーシーブ等）、オルソギ酸メチル、オルソ酢酸メチル等のオルソエステル類、オルソほう酸エステル、シリケート類やイソシアネート類（商品名：アディティブＴＩ）等が挙げられ、無水石膏、モレキュラーシーブが好ましく、特にモレキュラーシーブが好ましく用いられる。このような脱水剤は、１種または２種以上組み合わせて用いることができる。なお、無水石膏よりもモレキュラーシーブが特に好ましく用いられるのは、下記の理由による。すなわち、無水石膏が含有された防汚塗料組成物を塗布すると、塗布後のスウェットや降雨の際には、水溶性の水和した石膏が塗膜表面に析出し、塗膜の白化原因となることがあり、またこの防汚塗膜の表面にさらに上塗りを行なう場合には、上塗り性への影響が生ずる傾向があるため、これらを回避するには、モレキュラーシーブを用いることが特に好ましい。
【００８５】
なお、このような脱水剤との関係で、前記特開平７-１８２１６号公報記載の塗料組成物と対比しつつ本願発明についてさらに詳説すると、本願発明の防汚塗料組成物には、前記皮膜形成性共重合体として比較的低分子量のものが含有されているために、上記脱水剤が配合されていない防汚塗料組成物においてもある程度、貯蔵中の増粘ゲル化は抑制される。また、もし該防汚塗料組成物の長期貯蔵中に多少増粘し、ゲル化する傾向が認められたとしても、適宜選択された溶剤を用いて該防汚塗料組成物を希釈して船底等に塗布できれば、形成された塗膜は消耗性（自己研磨性）を有しており、良好な防汚性が認められる。このように増粘ゲル化してしているような防汚塗料組成物を塗布形成してなる塗膜であっても、消耗性を有しているのは、主として前述したような量で比較的低分子量の皮膜形成性共重合体が用いられているためであろうと思われる。
【００８６】
これに対して、前記特開平７-１８２１６号公報記載の塗料組成物では、脱水剤が配合されていないと、該塗料組成物の貯蔵中に顕著な増粘ゲル化傾向が見られ、このように増粘ゲル化した塗料組成物を船底等に塗布形成してなる塗膜では、消耗性は殆ど認められず、防汚性に劣る。
【００８７】
このような脱水剤は、上記被膜形成性共重合体１００重量部に対して、通常０．１〜２００重量部の量で、好ましくは１〜１００重量部の量で用いられる。
［タレ止め・沈降防止剤、顔料など］
タレ止め・沈降防止剤としては、有機粘土などのような防汚塗料組成物の貯蔵安定性を害するもの以外は、任意量で配合されていてもよい。このようなタレ止め・沈降防止剤としては、Ａｌ、Ｃａ、Ｚｎのステアレート塩、レシチン塩、アルキルスルホン酸塩などの塩類、ポリエチレンワックス、アミドワックス、水添ヒマシ油ワックス系，ポリアマイドワックス系および両者の混合物、合成微粉シリカ、酸化ポリエチレン系ワックス等が挙げられ、好ましくは水添ヒマシ油ワックス、ポリアマイドワックス、合成微粉シリカ、酸化ポリエチレン系ワックスが用いられる。このようなタレ止め・沈降防止剤としては、楠本化成（株）製の「ディスパロン305」、「ディスパロン4200-20」等の商品名で上市されているものが挙げられる。
【００８８】
顔料としては、前記鱗片状顔料（例：雲母粉）の他、従来公知の有機系、無機系の各種顔料（例：チタン白、ベンガラ）を用いることができる。なお、染料等の各種着色剤も含まれていてもよい。
【００８９】
溶剤としては、例えば、脂肪族系、芳香族系（例：キシレン、トルエン等）、ケトン系、エステル系、エーテル系など通常、防汚塗料に配合されるような各種溶剤が用いられる。
【００９０】
上記のような防汚塗料組成物を水中構造物（例：原子力発電所の給排水口）の表面に、あるいは、湾岸道路、海底トンネル、港湾設備、運河・水路等のような各種海洋土木設備の工事用の汚泥拡散防止膜の表面に、あるいは、船舶、漁具（例：ロープ、漁網）などの各種成形体の表面に常法に従って１回〜複数回塗布すれば、特に乾燥条件下に晒され、あるいは喫水線付近のように水中への浸漬と空気中への暴露とが繰り返されるような箇所での耐クラック性、経時変化の安定性に優れた防汚塗膜被覆船体または水中構造物などが得られる。なお、本発明に係る防汚塗料組成物は、直接上記船体または水中構造物等の表面に塗布してもよく、また予め防錆剤、プライマーなどの下地材が塗布された船体または水中構造物等の表面に塗布してもよい。さらには、既に従来の防汚塗料による塗装が行われ、あるいは本発明発明の防汚塗料組成物による塗装が行われている船体、水中構造物等の表面に、補修用として本発明の防汚塗料組成物を上塗りしてもよい。このようにして船体、水中構造物等の表面に形成された防汚塗膜の厚さは特に限定されないが、例えば、３０〜１５０μｍ／回程度である。
【００９１】
【発明の効果】
このような本発明に係る防汚塗料組成物は、特に空気中に晒されるなど乾燥下における耐クラック性、耐剥離性に優れ、しかも経時変化の安定性（すなわち、喫水線の変動により繰返して乾燥下に晒されたり、水中に浸漬されたりすることによっても経時変化しにくく、長期安定性を有すること）に優れた塗膜を形成できる。
【００９２】
特に、上記被膜形成性共重合体と酸化亜鉛とに加えて、さらに上記塩素化パラフィン、（メタ）アクリル酸エステル系重合体、脱水剤、防汚剤（酸化亜鉛を除く）などを含有する本発明の防汚塗料組成物では、上記効果に加えて、さらに船底などの基材あるいはプライマー層などに対する耐剥離性などの物性に優れ、防汚性、自己研磨性（消耗性）にも優れているような防汚塗膜を形成でき、しかも貯蔵安定性に優れている。
【００９３】
【実施例】
以下、本発明を実施例によりさらに具体的に説明するが、本発明は、これらの実施例により何等制限されるものではない。なお、以下の実施例、比較例等において、「部」は「重量部」の意味である。また、表中の各成分量例えば、共重合体成分量、塩素化パラフィン（塩パラ）量、着色顔料、亜酸化銅、亜鉛華などの量、あるいは溶媒（例：キシレン）量などは、特に断らない限りいずれも「重量部」表示で示す。
［ポリマーの製造例］
（共重合体Ｓ−１の製造）
攪拌機、コンデンサー、温度計、滴下装置、加熱・冷却ジャケットを備えた反応容器にキシレン１００部を仕込み窒素気流下で９０℃の温度条件に加熱攪拌を行った。
【００９４】
同温度を保持しつつ滴下装置より、上記反応器内にトリブチルシリルメタクリレート４０部、メチルメタクリレート６０部および重合開始剤の２，２’−アゾビスイソブチロニトリル１．２部の混合物を４時間かけて滴下した。
【００９５】
その後同温度で４時間攪拌を続けて無色透明の共重合体溶液Ｓ−１を得た。
得られた共重合体溶液Ｓ−１を１０５℃で３時間加熱した後の加熱残分は４９．９重量％であり、ＧＰＣによる残存モノマーの定量結果より各モノマーの９５重量％以上は、共重合体中に組み込まれ、反応中の重合率変化は各モノマーでほぼ等しく、これらのモノマーから誘導される各成分単位はほぼそれぞれ用いられたモノマー量比で、ランダムに配列しているものと考えられる。
【００９６】
またこの共重合体溶液Ｓ−１中の共重合体（加熱残分）Ｓ−１のガラス転移温度（Ｔｇ）は５１℃であり、共重合体溶液Ｓ−１の２５℃における粘度は２９５ｃｐｓであり、ＧＰＣ測定による数平均分子量（Ｍｎ）は１１２００であり、重量平均分子量（Ｍｗ）は２１２００であった。
（共重合体Ｓ−２〜共重合体Ｓ−６の製造）
上記共重合体Ｓ−１の製造の際に、滴下配合成分を表１に示すように変えた以外は、上記と同様にして共重合体Ｓ−２、共重合体Ｓ−３、共重合体Ｓ−４、共重合体Ｓ−５および共重合体Ｓ−６を得て、上記と同様にこれらの共重合体（溶液）の物性値を測定した。
【００９７】
結果を併せて表１に示す。
【００９８】
【表１】

【００９９】
防汚塗料組成物を構成する際に用いられる相溶性（メタ）アクリル酸エステル系重合体成分（溶液）の種類と物性値［加熱残分（重量％／重合体溶液）および該重合体成分中に含有される相溶性（メタ）アクリル酸エステル系重合体の粘度（ガードナー／２５℃）、分子量（Ｍｎ：ＧＰＣ測定による）、酸価（ＡＶ）、ガラス転移温度（Ｔｇ℃）］を測定した。
【０１００】
結果を表２に示す。
【０１０１】
【表２】

【０１０２】
[参考例１、実施例２、参考例３〜６、参考例８〜１４、実施例１５〜３１、比較例１〜
７及び９]
［防汚塗料組成物の製造例］表４〜表１１に示す配合組成の各防汚塗料組成物を製造した（各成分量は重量部表示）。
【０１０３】
表４〜表１１に示す配合組成の防汚塗料組成物を製造するに際しては、ガラスビーズを入れたペイントシェーカー内でこれらの配合成分を一緒にして２時間振とうした後、室温で１２時間熟成を行った。次いで１００メッシュのフィルターにて濾過して、所望の防汚塗料組成物を得た。
【０１０４】
該防汚塗料組成物についてストーマー粘度計で測定した製造直後の粘度（Ｋｕ値／２５℃）、および常温で１カ月貯蔵後の粘度を表１２〜１４に併せて示す。
また、該防汚塗料組成物を用いた防汚性、経時消耗度、乾湿交互部における物性、塗膜強度の評価を下記のようにして行った。
【０１０５】
結果を、表１２〜１４に示す。
［防汚性の評価］
広島湾の海水中に設置した回転ドラムの側面に取付け可能なように曲げ加工が施された７０×２００×３ｍｍのサンドブラスト板を用意した。このサンドブラスト板に、エポキシ系ジンクリッチプライマー（乾燥塗膜中の亜鉛末含有率８０重量％）、タールエポキシ系防食塗料、ビニル系バインダーコートをそれぞれの乾燥膜厚が２０μｍ、１５０μｍ、５０μｍとなるように順次重ねて塗装した後、供試防汚塗料組成物をその乾燥後の膜厚が２００μｍとなるように塗装し、試験板を得た。
【０１０６】
回転ドラムにこの試験板を取り付けて周速１５ノット、５０％稼働条件（夜間１２時間稼働、昼間１２時間停止の交互運転）にて１２カ月間船舶の運航をシュミレートした後、防汚性（動的防汚性，試験板への各種水棲生物の付着面積％）、消耗度μ（膜厚減少：表中★印欄）の評価を行った。
【０１０７】
また、下記のような条件で経時消耗度、乾湿交互部における物性、塗膜強度の評価をも行った。
［経時消耗度の評価］
直径３００ｍｍで厚さ３ｍｍの円盤状サンドブラスト板にエポキシ系ジンクリッチプライマー（乾燥塗膜中の亜鉛末含有率８０％のもの）を、その乾燥膜厚が２０μｍとなるように塗装した後、一日置いて、タールエポキシ系防食塗料をその乾燥膜厚が１５０μｍとなるように塗装した後、また一日置いて、さらにビニル系バインダーコートをその乾燥膜厚が５０μｍとなるように順次重ねて塗装した後、７日間室内で乾燥した。
【０１０８】
その後スキマ５００μｍのアプリケーターを用い供試防汚塗料組成物を半径方向に放射状に塗装し、試験板を得た。
２５℃の海水を入れた恒温槽中でモーターにこの試験板を取りつけ、周速１５ノットで１００％稼働条件（昼夜を問わず連続運転）で回転し、円周付近の消耗度（膜厚減少）を３ヶ月毎に４回測定した。
［乾湿交互部における物性の評価］
７０ｍｍ×１５０ｍｍ×２．３ｍｍのサンドブラスト板に、「防汚性の評価」で用いた塗装方法と同様の方法で塗装を行い、試験板を得た。
【０１０９】
この試験板を、１２時間の海水浸漬と１２時間の空中暴露とを繰り返す回転式乾燥交互試験機に取り付け、３ヶ月間この試験機の運転を行った後、目視にて該試験板の物性評価を行った。
【０１１０】
評価基準は以下の通り。
５：試験板表面に、ワレ、ハガレが認められない。
４：試験板表面に、微細なワレが僅かに認められる。
３：試験板表面に、微細なワレが認められる。
２：試験板表面に、顕著なワレが認められる。
１：試験板表面に、ハガレを伴う顕著なワレが認められる。
［塗膜強度の評価］
７０ｍｍ×１５０ｍｍ×２．３ｍｍのサンドブラスト板にタールエポキシ系防食塗料をその乾燥膜厚が１５０μｍとなるように塗装した後、１日置いて、その表面にさらにビニール系バインダーコートをその乾燥膜厚が５０μｍとなるように塗装し、次いで４０℃の恒温器中で２日間乾燥した。
【０１１１】
次いで、上記乾燥膜の表面に、さらにビニル系バインダーコートをその乾燥膜厚が５０μｍとなるように塗装した。
その翌日に、供試防汚塗料組成物をその乾燥膜厚が１５０μｍとなるように塗装した後、さらにその翌日にも、これと同じ防汚塗料組成物を１５０μｍの乾燥膜厚で塗装した（防汚塗料組成物よりなる乾燥膜厚合計：150+150=300μｍ）。
【０１１２】
次いで、温度２０℃で湿度７５％の恒温・恒湿室中で１４日間乾燥した。
このようにして得られた試験板の塗膜表面に、５０ｍｍ×５０ｍｍのポリエチレンシートを置き、その上に３０ｍｍ×３０ｍｍの模擬盤木を置いて、３０ｋｇ／ｃｍ²の荷重で３０分間加圧した後、塗膜のダメージを目視により評価した。
【０１１３】
評価基準は、以下の通り。
【０１１４】
【表３】

【０１１５】
上記評価結果を、併せて表１２〜１４に示す。
なお、表中の成分名称等は以下の通りである。
▲１▼「トヨパラックス150」
東ソー（株）製の塩素化パラフィン、平均炭素数：１４．５、塩素含有率（量）５０％、粘度：１２ポイズ／２５℃、比重：１．２５／２５℃。
▲２▼「トヨパラックスA-40」
東ソー（株）製の塩素化パラフィン、平均炭素数：２４．５、塩素含有率（量）４０．５％、粘度：１８．５ポイズ／２５℃、比重：１．１６／２５℃。
▲３▼「トヨパラックス 270」
東ソー（株）製の塩素化パラフィン、平均炭素数：１２、塩素含有率（量）７０％、粘度：４ポイズ／８０℃、比重：１．５０／８０℃。
▲４▼「トヨパラックスA-70」
東ソー（株）製の塩素化パラフィン、平均炭素数：２４．５、塩素含有率（量）７０％、白色粉体、比重：１．６５／２５℃。
▲５▼「モレキュラーシーブ４Ａ」
脱水剤、ユニオン昭和（株）製、合成ゼオライトパウダー。
▲６▼「ディスパロン305」
楠本化成（株）製の水添ヒマシ油系タレ止め剤。
▲７▼「ディスパロン4200-20」
楠本化成（株）製の酸化ポリエチレン系沈降防止剤、２０％キシレンペースト。
▲８▼「マイカ白玉」：（有）（脇元雲母）製の鱗片状顔料、平均粒径：１５μｍ、アスペクト比：４０。
【０１１６】
表中、「塩素化パラフィン（重量％）（対共重合体）」、「Ｃｕ₂Ｏ（重量％）（対共重合体、すなわち対被膜形成性共重合体、以下同じ）」、「ＺｎＯ（重量％）（対共重合体）」等の算出方法は、以下のとおりである。
【０１１７】
例えば「防汚塗料組成物Ｐ−１」では、「塩パラ（塩素化パラフィン）含有量（重量％）（対共重合体）」＝３０．８は、以下のようにして求められる。
すなわち、「防汚塗料組成物Ｐ−１」中には、塩素化パラフィンは４重量部の量で配合され、また「共重合体成分（溶液）Ｓ−１」は２６重量部の量で配合されており、この「共重合体成分（溶液）Ｓ−１」２６重量部中には、加熱残分（共重合体Ｓ−１）が４９．９重量％の量で含有されている。従って、「防汚塗料組成物Ｐ−１」では、「塩素化パラフィン（重量％）（対共重合体）」＝［４／｛２６×４９．９／１００｝］×１００％＝３０．８（重量％）となる。
【０１１８】
【表４】

【０１１９】
【表５】

【０１２０】
【表６】

【０１２１】
【表７】

【０１２２】
【表８】

【０１２３】
【表９】

【０１２４】
【表１０】

【０１２５】
【表１１】

【０１２６】
【表１２】

【０１２７】
【表１３】

【０１２８】
【表１４】

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an antifouling coating composition, a coating film formed from the antifouling coating composition, an antifouling method using the antifouling coating composition, and a hull or an underwater structure coated with the coating film. .
[0002]
More specifically, the present invention is excellent in the strength of the coating film, for example, can form a coating film having a strength capable of suppressing damage to the coating on the wood part where a large pressure is applied particularly during ship construction. Excellent resistance to cracking and peeling in alternating environments (dry and wet alternating parts), for example, immersion in seawater and exposure to air, such as in the vicinity of the waterline of a ship or the waterline of an underwater structure It is possible to form a coating film that is resistant to changes over time even in an environment where it is repeated and has excellent stability, and also has a stable scouring ability in seawater, such as ship bottoms, underwater structures, fishing nets, etc. Self-abrasive antifouling paint composition capable of effectively preventing adhesion of aquatic organisms to the surface, a coating film formed from the antifouling paint composition, an antifouling method using the antifouling paint composition, and Hull covered with the coating The other is related to underwater structures.
[0003]
TECHNICAL BACKGROUND OF THE INVENTION
The bottom of the ship, underwater structures, fishing nets, etc. are exposed to water for a long period of time, and animals such as shellfish and barnacles, algae such as laver (seaweed), or various aquatic organisms such as bacteria adhere to the surface Breeding can impair the appearance and impair its function.
[0004]
In particular, when such aquatic organisms adhere to and propagate on the bottom of the ship, the surface roughness of the entire ship increases, and there is a high risk of causing a decrease in ship speed and an increase in fuel consumption. Moreover, to remove such aquatic organisms from the ship bottom, a great amount of labor and work time are required at the dock. In addition, when bacteria adhere to and propagate on underwater structures or the like and slime (sludge-like material) adheres to them, they may rot, causing damage such as deterioration of their physical properties and a significant decrease in life.
[0005]
For this reason, conventionally, research and development of various antifouling paints has been made only from the viewpoint of preventing the above-described damage in a portion such as a ship bottom that is immersed in water exclusively.
In other words, in the past, it was practically used in consideration of the point that it was applied to parts where alternating dry and wet conditions were repeated, such as the waterline part of the hull and the vicinity of the waterline of the underwater structure, and the coating film strength in the board part Research and development have not been conducted from the viewpoint of designing extremely useful antifouling paints.
[0006]
For this reason, the present inventors are particularly excellent in crack resistance and peel resistance in dry and wet alternating portions, and are repeatedly immersed in seawater and exposed to air, for example, in the waterline portion of a ship. In such environments, it is possible to form a coating film that does not easily change over time and has excellent stability, and has particularly practical strength, such as a place where large pressure is applied, such as a wood block during ship construction. In an effort to find a self-polishing antifouling paint composition that can form a coating that can suppress damage even in
Surprisingly, the antifouling coating composition containing two components of a specific silyl ester copolymer and zinc oxide in a specific amount is particularly excellent in crack resistance and peeling resistance in wet and dry alternating parts. Even in a dry and wet alternating environment such as a water line part, it is hard to change over time and has excellent stability and coating film strength.For example, it has excellent strength that can suppress board damage to the extent that there is no practical problem. While finding that a film can be formed,
In addition to these components, we have found that antifouling paint compositions containing chlorinated paraffin and antifouling agents can effectively prevent the attachment of aquatic organisms to ship bottoms, underwater structures, fishing nets, etc. The invention has been completed.
[0007]
Conventionally, various antifouling paints have been applied to the bottom of the ship in order to prevent aquatic organisms and the like from being attached to parts such as the bottom of the ship that are immersed in water.
As such an antifouling paint, for example, a copolymer of tributyltin methacrylate and methyl methacrylate, and cuprous oxide (Cu₂And O). The copolymer in the antifouling coating is hydrolyzed in seawater to give bistributyltin oxide (tributyltin ether, Bu_ThreeSn-O-SnBu_Three: Bu is a butyl group) or tributyltin halide (Bu_ThreeReleases organotin compounds such as SnX: X is a halogen atom) and exhibits an antifouling effect, and the hydrolyzed copolymer itself becomes water-soluble and dissolves in seawater. Because it is a "type paint", the resin paint residue does not remain on the ship bottom coating surface, and an active surface can always be maintained.
[0008]
However, such organotin compounds are highly toxic and may cause marine pollution, generation of malformed fish, adverse effects on the ecosystem due to the food chain, etc. Development is required.
[0009]
Examples of such antifouling paints that do not contain tin include silyl ester antifouling paints described in JP-A-4-264170, JP-A-4-264169, and JP-A-4-264168. . However, in these publications, what is the resistance to cracking of the coating film obtained in particular, or the stability of change over time in an environment in which immersion in water and exposure to dry air are repeated? Not taught. These antifouling paints are inferior in antifouling properties as taught in JP-A-6-157941, JP-A-6-157940, etc., and cracks and peeling in water occur. There are also problems.
[0010]
JP-A-2-196869 discloses a block containing a carboxylic acid group blocked by a trimethylsilyl group, which is obtained by copolymerizing trimethylsilyl methacrylate, ethyl methacrylate and methoxyethyl acrylate in the presence of an azo polymerization initiator. An antifouling paint containing a modified acid functional copolymer (A) and a polyvalent cation compound (B) is taught, and the specific description of the invention includes a biocide against marine organisms. Examples thereof include zinc oxide, cuprous oxide and the like, and examples thereof include an antifouling paint containing a chlorinated paraffin plasticizer in addition to the acid functional copolymer (A) and a compound of a polyvalent cation. Is disclosed. However, the coating film obtained from the antifouling paint disclosed in this example has a problem that the crack resistance (particularly, crack resistance during drying) and the peel resistance are not sufficiently satisfactory. That is, in JP-A-2-196869, a coating film made of an antifouling paint containing any amount of zinc oxide is particularly excellent in crack resistance and peeling resistance during drying, and is immersed in seawater and dried. There is no teaching about whether it is difficult to change with time even under an environment where repeated exposure to air is repeated, and is excellent in stability.
[0011]
Japanese Patent Laid-Open No. 63-215780 discloses that a vinyl monomer having an organosilyl group, such as a trialkylsilyl ester of (meth) acrylic acid, is copolymerized with other vinyl monomers. Resin for antifouling paint having an average molecular weight of 3000 to 40000 is described. In the detailed description of the invention, an organic water binder such as trimethyl orthoformate, an antifouling agent such as cuprous oxide, Bengala, etc. In the antifouling paint resin composition described in the publication, it is inferior in crack resistance and peeling resistance especially during drying, and is immersed in water (drying). In an environment where repeated exposure to the air is repeated, there is a problem that it tends to change with time and is inferior in stability.
[0012]
In addition, Japanese Patent Publication No. 5-32433 corresponding to the above-mentioned Japanese Translation of PCT Publication No. 60-500342 discloses a poisonous substance (a) and a formula [(-CH₂-CXCOOR)-(B)-: X is H or CH_ThreeAnd R is SiR '_ThreeOr Si (OR ')_ThreeWherein R ′ represents an alkyl group, B represents an ethylenically unsaturated monomer residue, and a polymer binder (b) having a specific hydrolysis rate and the like. An antifouling paint comprising, zinc oxide and the like is exemplified as the antifouling poison (a), and further describes that it may contain a solvent, a water sensitive pigment component, an inert pigment, a filler, a retarder, and this In the section of production examples of test paints in JP-T-60-500342, an antifouling paint containing tributyltin methacrylate polymer (TBTM) and cuprous oxide is described, and silyl acrylate is substituted for this TBTM. Although it is described that a polymer can be used, the coating film obtained from the antifouling paint actually disclosed in this production example is inferior in crack resistance, particularly crack resistance at the time of drying, and in the vicinity of the water line, etc. Easy to change over time and stable There is a problem that it is inferior.
[0013]
In JP-A-7-18216, A) In the molecule, the formula: —COO—SiR¹R²R^Three(R¹~ R^ThreeIn the coating composition comprising as a main component an organosilicon-containing polymer having a triorganosilicon ester group represented by (1) an alkyl group having 1 to 18 carbon atoms, and B) copper or a copper compound, As an essential component other than the A and B components, the formula C):
[0014]
[Chemical 1]

[0015]
(R^Four~ R⁶Represents a hydrogen atom, an alkoxy group having 1 to 18 carbon atoms, a cycloalkoxy group, etc., and R⁷Represents an alkyl group having 1 to 18 carbon atoms, n represents an integer of 1 to 3), and a coating composition containing an alkoxy group-containing silicon compound is disclosed. In the column of composition and action, it is described that the coating composition may contain a pigment such as zinc oxide, a plasticizer such as chlorinated paraffin, and a resin such as an acrylic resin as necessary. In the examples, a coating composition containing a tri-n-butylsilyl methacrylate polymer, zinc oxide, a petiole, talc and the like is disclosed. However, this publication does not teach anything about the crack resistance of the obtained coating, especially when it is dried, or the stability over time near the water line.
[0016]
Japanese Patent Laid-Open No. 7-102193 discloses a formula:
[0017]
[Chemical 2]

[0018]
(However, R in the formula¹~ R^ThreeAre groups selected from an alkyl group and an aryl group, and may be the same group or different groups. X is an acryloyloxy group, a methacryloyloxy group, a maleoyloxy group or a fumaroyloxy group. And a monomer A represented by the formula: Y- (CH₂CH₂O)_n-R^Four(However, R^FourIs an alkyl group or an aryl group, Y is an acryloyloxy group or a methacryloyloxy group, and n is an integer of 1-25. ), A coating composition containing a monomer mixture copolymer containing the monomer B and an antifouling agent as essential components is disclosed. Zinc oxide is exemplified as the antifouling agent, and it is described that it is used in an amount of 0.1 to 80% by weight in the solid content of the paint. However, this publication does not teach anything about crack resistance at the time of drying, particularly the stability of change with time of the obtained coating film.
[0019]
As described above, in any of the above publications, a coating film composed of an antifouling paint of any composition is repeatedly cracked particularly during drying, or repeatedly immersed in water and exposed to dry air. No teaching is given as to whether it is excellent in stability over time in an environment.
[0020]
OBJECT OF THE INVENTION
The present invention seeks to solve the problems associated with the prior art as described above, and is particularly resistant to cracking and peeling, etc. under dry conditions such as being above the waterline of a hull, underwater structure, etc. It is easy to change over time by being exposed to dryness due to fluctuations in the waterline or being immersed in seawater, and can form a coating film with excellent long-term stability. An object of the present invention is to provide an antifouling coating composition capable of forming a coating film having excellent strength capable of suppressing damage caused by pressure even when a pressure such as wood is applied.
[0021]
More preferably, the present invention can form an antifouling coating film having excellent crack resistance in water, antifouling properties, and self-polishing properties (consumability) in addition to the above-mentioned purpose, and also has storage stability. An object is to provide an antifouling coating composition that is excellent.
[0022]
The present invention also provides a coating film formed from such an antifouling coating composition, an antifouling method using the antifouling coating composition, and a hull or underwater structure coated with the coating film. The purpose is that.
[0023]
SUMMARY OF THE INVENTION
The antifouling coating composition according to the present invention has a component unit derived from a trialkylsilyl ester of a polymerizable unsaturated carboxylic acid in an amount of 20 to 65% by weight, a number average molecular weight of 3000 to 20000, and a weight average molecular weight. Is a film-forming copolymer having a glass transition point of 25 to 80 ° C., a viscosity (25 ° C., CPS) in a 50% xylene solution of 40 to 1000, zinc oxide,A (meth) acrylic acid ester-based polymer having a number average molecular weight of 1000 to 100,000 which is compatible with the film-forming copolymer,
  The zinc oxide is contained in an amount of 1 to 1000 parts by weight and the (meth) acrylic acid ester polymer is contained in an amount of 5 to 200 parts by weight with respect to 100 parts by weight of the film-forming copolymer. ingAs a featureYes.
  In the preferred embodiment, zinc oxide is usually contained in an amount of 1 to 1000 parts by weight, preferably 3 to 500 parts by weight, based on 100 parts by weight of the film-forming copolymer. desirable.
[0024]
The antifouling paint composition according to the present invention may contain chlorinated paraffin in addition to the above-mentioned film-forming copolymer and zinc oxide. It is desirable that zinc oxide is contained in an amount as described above with respect to 100 parts by weight of the copolymer, and chlorinated paraffin is contained in an amount of 18 to 65 parts by weight, preferably 20 to 55 parts by weight. .
[0025]
In a preferred embodiment of the present invention, it is desirable that at least one of the three alkyl groups bonded to the silicon atom of the trialkylsilyl ester has 3 or more carbon atoms. Those having 4 or more carbon atoms in all groups are preferred, and the trialkylsilyl ester is particularly preferably tributylsilyl (meth) acrylate. The average carbon number of the chlorinated paraffin is 8 to 30, and the chlorine content is preferably 35 to 75%.
[0026]
The antifouling coating composition according to the present invention has a number average molecular weight compatible with the film-forming copolymer in addition to the film-forming copolymer and zinc oxide (meta ) Acrylic ester-based polymer may be contained, and in such an antifouling coating composition, zinc oxide is contained in an amount of 1 to 1000 parts by weight, preferably 3 parts per 100 parts by weight of the film-forming copolymer. It is contained in an amount of ˜500 parts by weight, and the (meth) acrylic acid ester polymer is contained in an amount of 5 to 200 parts by weight, preferably 10 to 200 parts by weight.
[0027]
In such an antifouling coating composition, the compatible (meth) acrylic acid ester polymer is a hydrophobic (meth) acrylic acid ester homopolymer, or two or more (meth) acrylic polymers. Desirably, it is at least one (meth) acrylic acid ester polymer selected from the group consisting of acid ester copolymers and (meth) acrylic acid ester / styrene copolymers. The glass transition temperature (Tg) of the (meth) acrylic acid ester polymer is preferably 0 ° C. or higher.
[0028]
The antifouling paint composition according to the present invention may further contain chlorinated paraffin in addition to the above-mentioned film-forming copolymer, zinc oxide, and the above-mentioned (meth) acrylic acid ester-based polymer. Well, in such an antifouling coating composition, zinc oxide is contained in an amount of 1 to 1000 parts by weight, preferably 3 to 500 parts by weight, based on 100 parts by weight of the film-forming copolymer. The acrylate polymer is contained in an amount of 5 to 200 parts by weight, preferably 10 to 200 parts by weight, and the chlorinated paraffin is contained in an amount of 5 to 150 parts by weight, preferably 8 to 100 parts by weight. It is desirable.
[0029]
The antifouling paint composition according to the present invention may contain a dehydrating agent in addition to the above-mentioned film-forming copolymer and zinc oxide. Zinc oxide is contained in an amount of 1 to 1000 parts by weight, preferably 3 to 500 parts by weight, based on 100 parts by weight of the polymer, and the dehydrating agent is 0.1 to 200 parts by weight, preferably 1 to 100 parts by weight. It is desirable that it is contained in an amount.
[0030]
The antifouling coating composition according to the present invention may contain the above-mentioned film-forming copolymer, zinc oxide, chlorinated paraffin, and a dehydrating agent. Zinc oxide is contained in an amount of 1 to 1000 parts by weight, preferably 3 to 500 parts by weight, and chlorinated paraffin is 3 to 200 parts by weight, preferably 5 to 150 parts by weight, based on 100 parts by weight of the copolymer. It is preferably contained in an amount of 18 to 65 parts by weight, and the dehydrating agent is contained in an amount of 0.1 to 200 parts by weight, preferably 1 to 100 parts by weight.
[0031]
The antifouling coating composition according to the present invention may contain the film-forming copolymer, zinc oxide, chlorinated paraffin, the (meth) acrylic acid ester polymer, and a dehydrating agent. In the antifouling coating composition, zinc oxide is contained in an amount of 1 to 1000 parts by weight, preferably 3 to 500 parts by weight, based on 100 parts by weight of the film-forming copolymer.
Chlorinated paraffin is contained in an amount of 3 to 200 parts by weight, preferably 5 to 150 parts by weight,
The (meth) acrylic acid ester polymer is contained in an amount of 1 to 200 parts by weight, preferably 5 to 200 parts by weight, particularly preferably 10 to 200 parts by weight,
The dehydrating agent is contained in an amount of 0.1 to 200 parts by weight, preferably 1 to 100 parts by weight.
[0032]
In any of the above antifouling coating compositions according to the present invention, an organic and / or inorganic antifouling agent (excluding zinc oxide) is added in an amount of, for example, 50 to 100 parts by weight based on 100 parts by weight of the film-forming copolymer. It is preferably contained in an amount of about 1500 parts by weight, and among such antifouling agents (biocides), copper or copper compounds (eg, cuprous oxide), zinc pyrithione, and the like are preferable.
[0033]
Among the antifouling coating compositions according to the present invention, in addition to the film-forming copolymer and zinc oxide, chlorinated paraffin, the (meth) acrylic acid ester polymer, a dehydrating agent or an antifouling agent ( In addition to the above effects, it can form a coating film with excellent resistance to cracking in water, antifouling properties, self-polishing properties (consumability), and storage stability. Is excellent. (In the present specification, unless otherwise specified, the terms “crack resistance and peel resistance” are used to include both in water and in (dry) air.)
The antifouling coating film according to the present invention is formed from the above antifouling coating composition.
[0034]
The antifouling method for a hull or underwater structure according to the present invention is characterized by using the antifouling paint composition.
The antifouling coating film hull or underwater structure according to the present invention is characterized in that the surface of the hull or underwater structure is coated with a coating film made of the above antifouling coating composition.
[0035]
According to the one-pack type antifouling paint composition according to the present invention as described above, it is excellent in crack resistance, peel resistance, particularly crack resistance under drying such as being exposed to air, and peel resistance. Forms a coating film with excellent stability over time (that is, it is difficult to change over time even if it is repeatedly exposed to drying due to fluctuations in the waterline, etc., or immersed in water, and has long-term stability). it can.
[0036]
In particular, in addition to the film-forming copolymer and zinc oxide, the book further contains the chlorinated paraffin, (meth) acrylic acid ester polymer, dehydrating agent, antifouling agent (excluding zinc oxide), etc. In addition to the above effects, the antifouling paint composition of the invention is further excellent in physical properties such as peel resistance to a base material such as a ship bottom or a primer layer, and also excellent in antifouling properties and self-polishing properties (consumability). The antifouling coating film can be formed, and it is excellent in storage stability.
[0037]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the antifouling paint composition according to the present invention will be specifically described.
The antifouling paint composition according to the present invention contains the following film-forming copolymer and zinc oxide, and the zinc oxide is based on 100 parts by weight of the film-forming copolymer. Usually, it is contained in an amount of 1 to 1000 parts by weight, preferably 3 to 500 parts by weight. According to such a one-pack type antifouling paint composition according to the present invention, it is excellent in crack resistance, peel resistance, particularly crack resistance under drying such as exposure to air, and changes with time. Stability (i.e., anti-fouling coatings such as hulls and underwater structures are repeatedly exposed to dryness due to fluctuations in the waterline, etc., and are less likely to change over time, resulting in long-term stability. It is possible to form an excellent coating film. When the amount of zinc oxide is less than 1 part by weight, for example, when the coating film is exposed to the air such as being exposed to the air, cracks and peeling easily occur, and more than 1000 parts by weight. With regard to the amount, no further improvement in the effect can be expected, and there is a tendency to cause cracks during coating and drying caused by an excessively high pigment concentration, and an increase in the amount of dust during spray coating.
[0038]
[Film-forming copolymer]
The film-forming copolymer has a component unit derived from a trialkylsilyl ester of a polymerizable unsaturated carboxylic acid in an amount of 20 to 65% by weight and a number average molecular weight of 3000 to 50000.
[0039]
This trialkylsilyl ester is represented, for example, by the following formula [I]:
[0040]
[Chemical Formula 3]

[0041]
It is represented by In this formula [I], R¹Represents an alkyl group such as a hydrogen atom or a methyl group, and R², R^ThreeAnd R^FourRepresents an alkyl group having about 1 to 18 carbon atoms, such as a methyl group, an ethyl group, a propyl group, or a butyl group;², R^ThreeAnd R^FourMay be different from each other or the same. Specific examples of such trialkylsilyl esters include (meth) acrylic acid trimethylsilyl ester, (meth) acrylic acid triethylsilyl ester, (meth) acrylic acid tripropylsilyl ester, and (meth) acrylic acid tributyl. R like silyl ester², R^ThreeAnd R^FourAre the same trialkylsilyl esters,
R such as (meth) acrylic acid dimethylpropylsilyl ester, (meth) acrylic acid monomethyldipropylsilyl ester, (meth) acrylic acid methylethylpropylsilyl ester, etc.², R^ThreeAnd R^FourAnd trialkylsilyl esters in which one part or all of them are different from each other. In the present invention, such trialkylsilyl esters may be used alone or in combination of two or more. Among such trialkylsilyl esters, R², R^ThreeAnd R^FourIn which at least one of the alkyl groups has 3 or more carbon atoms, and preferably all of these three alkyl groups have 4 or more carbon atoms.², R^ThreeAnd R^FourThose having a total carbon number of about 5 to 21 are preferred. Among such trialkylsilyl esters, in particular, the ease of synthesis of trialkylsilyl esters, or the film-forming properties, storage stability, and scouring properties of antifouling coating compositions using such trialkylsilyl esters. In view of the ease of control, (meth) acrylic acid tributylsilyl ester is most preferably used.
[0042]
As a monomer (comonomer) copolymerized with such a trialkylsilyl ester, any polymerizable unsaturated compound (ethylenically unsaturated monomer) can be used. As such a polymerizable unsaturated compound, Specifically, alkyl (meth) acrylates such as (meth) acrylic acid methyl ester, (meth) acrylic acid ethyl ester, (meth) acrylic acid 2-ethylhexyl ester, (meth) acrylic acid cyclohexyl ester, etc. Examples thereof include styrenes such as esters, styrene and α-methylstyrene, vinyl esters such as vinyl acetate and vinyl propionate, and preferably, methyl methacrylate (MMA) is used. Such MMA is usually contained in a comonomer (ethylenically unsaturated monomer) in an amount of usually 30% by weight or more, preferably 50% by weight or more. In the copolymer containing the glass, the glass transition temperature (Tg) is as high as 30 to 60 ° C., for example, and the strength of the coating film made of an antifouling coating composition containing chlorinated paraffin as described later is high. Not lowered.
[0043]
The component unit derived from the polymerizable unsaturated compound such as this (meth) acrylic acid alkyl ester and the component unit derived from the trialkylsilyl ester are each used as a raw material in the copolymer. The ethylene bond of the monomer is cleaved and usually bonded randomly.
[0044]
In addition, if a carboxylic acid residue is present in such a copolymer, the storage stability of the resulting antifouling coating composition is significantly reduced. It is desirable that is not present. In synthesizing the copolymer, it is preferable to use a high-purity monomer having no carboxylic acid residue.
[0045]
In such a film-forming copolymer, as described above, one or more component units derived from a trialkylsilyl ester of a polymerizable unsaturated carboxylic acid as described above (trialkylsilyl ester) Such a trialkylsilyl ester component unit may be contained in an amount of 20 to 65% by weight, preferably 30 to 55% by weight. It is preferable that it is contained in the antifouling coating composition because an antifouling coating film having excellent long-term antifouling properties can be obtained from this antifouling coating composition. Moreover, the number average molecular weight (Mn) of this copolymer by GPC measurement is 3000-50000, Preferably it is 3000-20000, More preferably, it is 4000-15000, Most preferably, it is 5000-12000, and a weight average molecular weight (Mw). ) Is usually 4000-150,000 (150,000), preferably 4000-60000 (60,000), more preferably 6000-30000 (30,000), and the molecular weight distribution (Mw / Mn) of this copolymer ) Is usually 1.0 to 4.0, preferably 1.0 to 3.0, particularly preferably 1.0 to 2.5, and the glass transition temperature (Tg ° C.) of the copolymer. ) Is usually 15 to 80 ° C, preferably 25 to 80 ° C, more preferably 30 to 70 ° C, and particularly preferably 35 to 60 ° C. Preferred, The viscosity of for example, 50% xylene solution of the copolymer (25 ° C., CPS) is usually 30 to 1000, it is desirable that preferably is 40 to 600.
[0046]
When the number average molecular weight of this copolymer is within the above range (1000 to 50000), the coating film antifouling performance for a long period of time, the damage resistance (impact resistance) of the formed coating film, and the resulting coating composition The storage stability of the film and the crack resistance of the coating film become excellent.
[0047]
Specific examples of such a film-forming copolymer include the following, and preferably the film-forming properties shown by the numbering (1) and (2), more preferably the numbering (1). A copolymer is used.
(1): A copolymer of tributylsilyl methacrylate (I) and methyl methacrylate (MMA), the copolymerization ratio ((I) / (MMA): weight ratio) of 35 to 65/65 to 35 (Total component total 100 parts by weight), number average molecular weight (Mn) is 3000 to 50,000, preferably 5000 to 12000, and weight average molecular weight (Mw) is 4000 to 150,000, preferably 6000 to 30000 (3 And a molecular weight distribution (Mw / Mn) of 1.0 to 4.0, preferably 1.0 to 2.5, and a glass transition temperature (Tg ° C) of 30 to 70 ° C, preferably 35. Having a viscosity (25 ° C., CPS) in a 50% xylene solution of 30 to 1000, preferably 40 to 600, for example,
(2): A copolymer of tripropylsilyl methacrylate (b), methyl methacrylate (MMA) and 2-ethylhexyl acrylate (c), and its copolymerization ratio ((b) / (MMA) / (c) : Weight ratio) is 25 to 55/74 to 35/1 to 10 (total 100 parts by weight of all components), the number average molecular weight (Mn) is 3000 to 50,000, preferably 5000 to 12000, and the weight average molecular weight. (Mw) is 4000-150,000, preferably 6000-30000 (30,000), and the molecular weight distribution (Mw / Mn) is 1.0-4.0, preferably 1.0-2.5, Glass transition temperature (Tg ° C) is 30-70 ° C, preferably 35-60 ° C, for example, its viscosity (25 ° C, CPS) in a 50% xylene solution is 30-1500, preferably 40-1000,
(3): A copolymer of tributylsilyl methacrylate (b), tripropylsilyl methacrylate (b), and methyl methacrylate (MMA), the copolymerization ratio ((b) / (b) / (MMA ): Weight ratio) is 30-60 / 1-20 / 69-20 (total 100 parts by weight of all components), number average molecular weight (Mn) is 3000-50,000, preferably 5000-12000, weight average. The molecular weight (Mw) is 4000-150,000, preferably 6000-30000 (30,000), and the molecular weight distribution (Mw / Mn) is 1.0-4.0, preferably 1.0-2.5. The glass transition temperature (Tg ° C) is 30 to 60 ° C, preferably 35 to 55 ° C. For example, the viscosity (25 ° C, CPS) in a 50% xylene solution is 30 to 1000, preferably 40 to 400 ,
{Circle around (4)} A copolymer of tributylsilyl methacrylate (I), tripropylsilyl methacrylate (b), methyl methacrylate (MMA), and 2-ethylhexyl acrylate (c), the copolymerization ratio (( A) / (b) / (MMA) / (c): weight ratio) is 30 to 60/1 to 20/68 to 19/1 to 10 (100 parts by weight in total of all components), and the number average molecular weight (Mn ) Is 3000 to 50,000, preferably 5000 to 12000, the weight average molecular weight (Mw) is 4000 to 150,000, preferably 6000 to 30000 (30,000), and the molecular weight distribution (Mw / Mn) is 1. 0 to 4.0, preferably 1.0 to 2.5, and a glass transition temperature (Tg ° C.) of 30 to 60 ° C., preferably 35 to 55 ° C., for example, its viscosity in a 50% xylene solution (25 C, CPS) 0 to 1000, preferably those of 40 to 400,
(5): A copolymer of tributylsilyl methacrylate (I), methyl methacrylate (MMA), and 2-ethylhexyl acrylate (C), and the copolymerization ratio ((I) / (MMA) / (C ): Weight ratio) is 35 to 65 / 64.9 to 34.9 / 0.1 to 10 (total 100 parts by weight of all components), and the number average molecular weight (Mn) is 3000 to 50,000, preferably 5000 to 12000, the weight average molecular weight (Mw) is 4000-150,000, preferably 6000-30000 (30,000), and the molecular weight distribution (Mw / Mn) is 1.0-4.0, preferably 1.0. To 2.5, glass transition temperature (Tg ° C.) of 30 to 70 ° C., preferably 35 to 60 ° C., for example, its viscosity (25 ° C., CPS) in a 50% xylene solution is 30 to 1000, preferably 40 ~ 600 ,
(6): A copolymer of triisopropylsilyl acrylate (d), methyl methacrylate (MMA) and ethyl acrylate (e), and its copolymerization ratio ((d) / (MMA) / (e): weight) Ratio) is 40 to 65/59 to 20/1 to 20 (total 100 parts by weight of all components), the number average molecular weight (Mn) is 1000 to 50,000, preferably 3000 to 30000 (30,000), and the weight The average molecular weight (Mw) is 1000-150,000, preferably 3000-30,000, the molecular weight distribution (Mw / Mn) is 1.0-4.0, preferably 1.0-3.0, and the glass transition The temperature (Tg ° C.) is 20 to 80 ° C., preferably 25 to 75 ° C., for example, the viscosity (25 ° C., CPS) in a 50% xylene solution is 30 to 1500, preferably 40 to 1300,
(7): A copolymer of triisobutylsilyl methacrylate (f), methyl methacrylate (MMA) and 2-ethylhexyl acrylate (c), and the copolymerization ratio ((f) / (MMA) / (c) ): Weight ratio) is 35 to 65 / 64.9 to 34.9 / 0.1 to 10 (total 100 parts by weight of all components), and the number average molecular weight (Mn) is 1000 to 50,000, preferably 3000 to 12000, the weight average molecular weight (Mw) is 1000-150,000, preferably 3000-30000 (30,000), and the molecular weight distribution (Mw / Mn) is 1.0-4.0, preferably 1.0- 2.5, a glass transition temperature (Tg ° C.) of 25 to 80 ° C., preferably 30 to 70 ° C., for example, its viscosity (25 ° C., CPS) in a 50% xylene solution is 30 to 2000, preferably 40-1500 Of,
Such.
[0048]
In order to prepare such a film-forming copolymer, for example, in an inert solvent such as a nitrogen stream, in an organic solvent such as xylene, a trialkylsilyl ester such as tributylsilyl methacrylate and a comonomer A polymerizable unsaturated compound containing methyl methacrylate in an amount of 50% by weight or more (eg, 80% by weight), an azo type or a peroxide type such as 2,2′-azobisisobutyronitrile, etc. In the presence of a polymerization initiator such as n-octyl mercaptan as necessary, and a reaction such as radical polymerization at a temperature of about 50 to 120 ° C. for about 2 to 12 hours. .
[0049]
The film-forming copolymer thus obtained contains each component unit in an amount corresponding to the amount of each monomer used.
The polymerization method is not limited to the simple radical solution polymerization method, and various conventionally known methods can be employed. The solvent can be arbitrarily selected from various solvents commonly used for paints, such as aliphatics, ketones, esters and ethers, in addition to the aromatics (eg, xylene). As the solvent, a solvent having a low water content is particularly preferable. Use of such a low water solvent is preferable because the hydrolysis reaction during and after the reaction can be avoided. In addition, since the alcohol solvent has a high initial moisture content and has reactivity with silanol, it is not appropriate to use the alcohol solvent during the reaction from this viewpoint.
[0050]
[Production of antifouling paint composition]
Such an antifouling coating composition can be produced by appropriately using a conventionally known method. For example, the antifouling coating composition can be produced, for example, with respect to 100 parts by weight of the film-forming copolymer and the film-forming copolymer. Zinc oxide in an amount of 1 to 1000 parts by weight, chlorinated paraffin in an amount of 18 to 65 parts by weight as described later, and an antifouling agent in an amount of 50 to 1500 parts by weight (for example, suboxidation) Copper (80-1200 parts by weight), 0.1-200 parts by weight of dehydrating agent (eg, anhydrous gypsum, molecular sieve) and any amount of anti-sagging / precipitating agent, pigment, solvent, etc. Alternatively, they may be added in any order and stirred, mixed, and dispersed.
[0051]
Such an antifouling coating composition according to the present invention contains a film-forming copolymer and zinc oxide (zinc white). In addition to this, a chlorinated paraffin, an antifouling agent, as described later. It may contain (meth) acrylic acid ester polymer, dehydrating agent, sagging / precipitating agent, scaly pigment, solvent and the like.
[0052]
[Chlorinated paraffin]
That is, in a preferred embodiment of the present invention, the antifouling coating composition may further contain chlorinated paraffin (chlorinated paraffin; salt para) in addition to the film-forming copolymer and zinc oxide. Good. In such an antifouling coating composition, zinc oxide is usually contained in an amount of 1 to 1000 parts by weight, preferably 3 to 500 parts by weight, based on 100 parts by weight of the film-forming copolymer. The paraffin is desirably contained in an amount of 18 to 65 parts by weight, preferably 20 to 55 parts by weight. Further, in such an antifouling coating composition, the antifouling agent as described later is usually 50 to 1500 parts by weight, preferably 80 to 1200 parts by weight with respect to 100 parts by weight of the film-forming copolymer. It is desirable that it is contained in an amount.
[0053]
Chlorinated paraffin is immersed in water (including fresh water and seawater; the same shall apply hereinafter) crack resistance of a coating film (also referred to as “antifouling coating film” in the present specification) comprising the resulting antifouling coating composition. The chlorinated paraffin may be linear or branched and may be liquid or solid (powder) at room temperature. However, those having an average carbon number of usually 8 to 30, preferably 10 to 26 are preferably used, and the number average molecular weight is usually 200 to 1200, preferably 300 to 1100, and the viscosity is usually 1 or more ( (Poise / 25 ° C.), preferably 1.2 or more (poise / 25 ° C.), with a specific gravity of 1.05-1.80 / 25 ° C., preferably 1.10-1.70 / 25 ° C. Preferably used. When such a carbon number chlorinated paraffin is used, a coating film with little cracking and peeling can be formed using the resulting antifouling coating composition. In addition, it is preferable that the carbon number of a chlorinated paraffin exists in the range of 8-30 from the suppression effect of a crack, and the consumable property (upgradability) and antifouling property of the coating film surface obtained. The chlorination rate (chlorine content: wt%) of the chlorinated paraffin is usually 35 to 75%, preferably 35 to 65%. When chlorinated paraffin having such a chlorination rate is used, a coating film with little cracking and peeling can be formed using the resulting antifouling coating composition. When the chlorination rate of the chlorinated paraffin is in the range of 35 to 75%, the miscibility (compatibility) with the film-forming copolymer (silyl ester copolymer) and the crack suppressing effect were obtained. Excellent wear and antifouling properties of the coating surface. Examples of such chlorinated paraffin include “Toyoparax 150” and “Toyoparax A-70” manufactured by Tosoh Corporation. In the present invention, two or more kinds of chlorinated paraffins having different chlorine contents and carbon numbers can be used in appropriate combination. When two or more kinds of chlorinated paraffins are used in combination, the carbon number and chlorination rate of the chlorinated paraffin are the carbon number or chlorine of these chlorinated paraffins contained in the antifouling coating composition. The average value of the conversion rate is shown.
[0054]
In the antifouling coating composition according to the present invention, such chlorinated paraffin is used in an amount of 3 to 200 parts by weight, preferably 5 to 150 parts by weight, based on 100 parts by weight of the film-forming copolymer. It is preferably contained in an amount of 18 to 65 parts by weight, more preferably 20 to 55 parts by weight, particularly preferably 20 to 50 parts by weight. When the amount of the chlorinated paraffin is in the range of 18 to 65 parts by weight, the effect of suppressing cracks generated in the coating film formed with the antifouling coating composition is excellent, and the coating film strength and damage resistance (impact) resistance. To become better.
[0055]
Thus, the antifouling coating composition in which chlorinated paraffin or the like is blended as described above in addition to the above-mentioned film-forming copolymer and zinc oxide is one-component and excellent in storage stability. Even if the coating film (antifouling coating film) made of this antifouling coating composition formed on the ship bottom is exposed to the air and submerged, cracks in the antifouling coating film are suppressed. Moreover, when this antifouling coating composition is applied to the primer surface, peeling of the antifouling coating film from the applied primer surface is suppressed. In addition, the antifouling coating film of the present invention has already been applied by coating the bottom of the ship with various antifouling paints including coating with the antifouling paint composition of the present invention a plurality of times, or by using the antifouling paint composition of the present invention. In the case where repair coating or the like is performed on the surface of the ship bottom or the like formed, peeling of the surface antifouling coating film of the present invention from the surface of the antifouling coating film previously applied and formed is suppressed. In addition, the antifouling coating film of the present invention applied and formed on the primer surface or the surface of the ship bottom to be repaired in this way can be controlled for consumption, and the necessary degree of wear and prevention can be reduced depending on the environment used. Dirty power (sex) can be provided. Therefore, this antifouling coating composition is economically superior because the film thickness of the antifouling coating film to be formed can be reduced to the maximum according to the application.
[0056]
[Anti-fouling agent]
The antifouling paint composition according to the present invention does not necessarily contain an antifouling agent, but preferably contains an antifouling agent.
[0057]
Such an antifouling agent may be organic or inorganic (excluding zinc oxide) and is not particularly limited. Specifically, for example, cuprous oxide ( Cu₂In addition to copper or copper compounds such as O), copper powder, cuprous thiocyanate (rhodan copper), etc., metal-pyrithione and its derivatives represented by the following formula [II] [wherein R¹~ R^FourEach independently represents hydrogen, an alkyl group, an alkoxy group, or a halogenated alkyl group, M represents a metal such as Zn, Cu, Na, Mg, Ca, Ba, Pb, Fe, or Al, and n represents a valence. Show]:
[0058]
[Formula 4]

[0059]
, Tetramethylthiuram disulfide, carbamate toxicants (eg zinc dimethyldithiocarbamate, manganese-2-ethylenebisdithiocarbamate), 2,4,5,6-tetrachloroisophthalonitrile, N, N-dimethyldichlorophenylurea 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one, 2,4,6-trichlorophenylmaleimide, pyridine triphenylborane and rhodan copper, preferably cuprous oxide Is used. Antifouling agents other than cuprous oxide are preferably used in combination with cuprous oxide. As the antifouling agent used in combination with cuprous oxide, 2-pyridinethiol-1-oxide zinc salt (zinc pyrithione) is used. preferable.
[0060]
Such antifouling agents can be used alone or in combination.
Such an antifouling agent may be a type of antifouling agent, a film-forming copolymer or the like used in preparing the antifouling coating composition, or a type of ship or the like on which such an antifouling coating composition is applied and formed (ship However, it is not determined more generally than for ocean-going coastal use, various seawater areas, wooden-steel-aluminum ships, etc.), but the antifouling agent is used with respect to 100 parts by weight of the film-forming copolymer. The total amount is usually 50 to 1500 parts by weight, preferably 80 to 1200 parts by weight.
[0061]
For example, when the cuprous oxide is used as an antifouling agent, the cuprous oxide is usually contained in an antifouling coating composition in an amount of about 80 to 1200 parts by weight with respect to 100 parts by weight of the film-forming copolymer. It may be contained in.
[0062]
[(Meth) acrylic acid ester polymer]
In the antifouling coating composition according to the present invention, the number average molecular weight compatible with the film-forming copolymer is 1,000 to 100,000 (100,000 (100,000) in addition to the film-forming copolymer and zinc oxide. ) (Meth) acrylic acid ester polymer [a (meth) acrylic acid ester homopolymer or copolymer other than (meth) acrylic acid silyl ester] may be contained.
[0063]
In the antifouling coating composition of the present invention, in addition to the film-forming copolymer, zinc oxide and the chlorinated paraffin, a (meth) acrylic acid ester system compatible with the film-forming copolymer. When the polymer is blended, the crack resistance of the resulting coating film can be further improved, the seawater consumption rate of the coating film and the durability of the antifouling performance can be adjusted to a suitable range, and When the antifouling coating composition of the present invention is overcoated on an existing antifouling coating film, there is an advantage that the effect of further improving the adhesion of the obtained coating film can be exhibited. Even if the blending amount of the chlorinated paraffin is reduced, there is an advantage that the crack resistance of the obtained coating film can be improved.
[0064]
As the (meth) acrylic acid ester-based polymer compatible with such a film-forming copolymer, (meth) other than the (meth) acrylic acid silyl ester used for preparing the film-forming copolymer. Examples include homopolymers or copolymers of acrylic acid esters, (meth) acrylic acid ester homopolymers, copolymers of at least two (meth) acrylic acid esters, (meth) acrylic acid esters, Examples thereof include styrene copolymers. Such (meth) acrylic acid ester polymers can be used alone or in combination of two or more.
[0065]
These (meth) acrylic acid ester-based polymers may be, for example, chain-like or branched as long as they are compatible with the film-forming copolymer, and have a crosslinked structure. Also good.
[0066]
Here, the film-forming copolymer and the “compatible” (meth) acrylate polymer are a film-forming copolymer (also referred to as a trialkylsilyl (meth) acrylate copolymer) concentration of 30. When the xylene solution of wt% and the xylene solution of (meth) acrylic acid ester polymer concentration of 30 wt% are mixed at 25 ° C. at a volume ratio of 1: 1, a transparent uniform solution is obtained, or 2 A (meth) acrylic acid ester-based polymer that forms a milky white uniform solution without forming a liquid separation layer.
[0067]
In addition, if the number average molecular weight of the (meth) acrylic acid ester polymer is in the above range, it is possible to effectively suppress cracking and adjust the degree of wear, and to prevent static contamination. There exists a tendency which can form the antifouling coating film excellent also in the property. In addition, when the number average molecular weight of the (meth) acrylic acid ester polymer exceeds the above range, the antifouling coating film obtained has a large effect of suppressing cracks and a large effect of reducing the degree of wear. If the molecular weight of the (meth) acrylic acid ester polymer is smaller than the above range, the antifouling property of the resulting antifouling coating can be kept high, but cracks can be suppressed. The effect tends to decrease.
[0068]
Examples of such a (meth) acrylate polymer include, for example, methyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, (meth) Homopolymers of (meth) acrylic acid esters such as cyclohexyl acrylate and phenyl (meth) acrylate, or copolymers of these monomers,
Examples thereof include copolymers of various monomers such as aromatic vinyl compounds such as styrene (ST), vinyl acetate, vinyl chloride, ethylene, propylene, butadiene, and vinyl ether compounds, and (meth) acrylic acid ester monomers.
[0069]
As such (meth) acrylic acid ester polymer, specifically, for example,
(1): Copolymer of methyl methacrylate (MMA) and butyl methacrylate (BMA), the copolymerization ratio (indicated by the weight ratio of each component, the same shall apply hereinafter) (MMA / BMA) 30-70 / 70-30 (all components total 100 parts by weight), number average molecular weight is 1000-100,000, preferably 1000-50,000,
(2): A copolymer of isobutyl methacrylate (i-BMA), t-butyl methacrylate (t-BMA), styrene (ST) and stearyl methacrylate (SLMA), and the copolymer The ratio (i-BMA / t-BMA / ST / SLMA) is 10-40 / 10-40 / 20-60 / 5-20 (total 100 parts by weight of all components), and the number average molecular weight is 1000-100,000, Preferably about 1000 to 80,000,
(3): A methyl methacrylate (MMA) homopolymer having a number average molecular weight of 1,000 to 100,000, preferably about 1,000 to 20,000,
(4): Ethyl methacrylate (EMA) homopolymer having a number average molecular weight of 1,000 to 100,000, preferably about 1,000 to 20,000,
(5): Copolymer of methyl methacrylate (MMA) and butyl acrylate (BA), with a copolymerization ratio (MMA / BA) of 90 to 10/10 to 90 (total 100 parts by weight of all components) ) Having a number average molecular weight of 1,000 to 100,000, preferably about 1,000 to 50,000,
{Circle around (6)} A copolymer of ethyl methacrylate (EMA) and butyl acrylate (BA) having a copolymerization ratio (EMA / BA) of 100 to 70/0 to 30 (total 100 parts by weight of all components) ) Having a number average molecular weight of 1,000 to 100,000, preferably about 1,000 to 30,000,
And so on.
[0070]
Among such (meth) acrylic acid ester polymers,
Preferably, a hydrophobic acrylic polymer (with a (meth) acrylic acid ester content of more than 50% by weight and a styrene content of less than 50% by weight), or a styrene polymer (with a styrene content of 50% by weight or more) The (meth) acrylic acid ester-based polymers having the numbering (1) and (2) are particularly preferably used.
[0071]
The glass transition temperature (Tg) of such a (meth) acrylic acid ester polymer is preferably 0 ° C. or higher, and particularly preferably 20 to 105 ° C. In addition, in the (meth) acrylic acid ester-based polymer having a low glass transition temperature (Tg) (eg, butyl acrylate (BA) homopolymer), the effect of suppressing cracks in the resulting antifouling coating film may be low. .
[0072]
In addition, such a (meth) acrylic acid ester polymer is usually used for 100 parts by weight of the film-forming copolymer in the film-forming copolymer-containing antifouling coating composition containing no chlorinated paraffin. Although used in an amount of 10 to 200 parts by weight, the antifouling coating composition containing this chlorinated paraffin can be further reduced, and 5 to 200 parts by weight with respect to 100 parts by weight of the film-forming copolymer. Can be used.
[0073]
That is, in such an antifouling coating composition, zinc oxide is contained in an amount of 1 to 1000 parts by weight, preferably 3 to 500 parts by weight, with respect to 100 parts by weight of the film-forming copolymer.
The (meth) acrylic acid ester polymer is usually contained in an amount of 1 to 200 parts by weight, preferably 5 to 200 parts by weight, more preferably 10 to 200 parts by weight, particularly preferably 15 to 160 parts by weight,
The chlorinated paraffin is usually contained in an amount of 3 to 200 parts by weight, preferably 5 to 150 parts by weight, and more preferably 8 to 100 parts by weight. In such an antifouling coating composition, the antifouling agent is usually contained in an amount of 100 to 2000 parts by weight, preferably 150 to 1500 parts by weight, based on 100 parts by weight of the film-forming copolymer. It is desirable that When the chlorinated paraffin content is in the range of 5 to 150 parts by weight, the effect of suppressing cracks in the obtained antifouling coating film and the mechanical strength of the obtained antifouling coating film are particularly excellent.
[0074]
In such a (meth) acrylic acid ester-based polymer, as in the case of the film-forming copolymer, if a carboxylic acid residue is present, storage of the resulting antifouling coating composition is possible. In order to significantly reduce the stability, it is desirable that no carboxylic acid residue is present in the (meth) acrylic acid ester polymer, and the acid value (AV value) of the polymer is usually 15 or less, more preferably 10 In the following, it is preferable to use a monomer having no carboxylic acid residue so that it is particularly preferably 5 or less.
[0075]
In this antifouling coating composition, for example, even if a coating film (antifouling coating film) made of this antifouling coating composition formed on the ship bottom is submerged, cracks in the antifouling coating film are suppressed and consumed. Control is possible, and a necessary wear level and antifouling performance can be provided according to the environment used. Therefore, in the antifouling coating composition containing the (meth) acrylic acid ester-based polymer in this way, the film thickness of the antifouling coating film can be reduced to the maximum according to the use. Also excellent.
[0076]
[Scale pigments]
The antifouling paint composition according to the present invention may contain the following scaly pigments in addition to the above-mentioned film-forming copolymer, the above-mentioned zinc oxide, and the above-mentioned chlorinated paraffin. .
[0077]
Examples of the scaly pigment include mica powder, scaly aluminum powder, copper powder, zinc dust, pearl pigment, and the like, and mica powder is preferably used.
More specifically, such as mica powder ore, more specifically, white eel series such as white peach, red peach, saw down peach, sericite, vanadine peach, illite,
In addition to the Chronomo series such as Chronomo, Kinunmo, Tetsuunmo, Chinwaldmo,
Examples thereof include calyokite and celadonite, but generally white ground pulverized material is used.
[0078]
The average particle diameter, aspect ratio, and the like of such scaly pigments are not particularly limited, but preferably the average particle diameter is 0.1 to 200 μm, and the aspect ratio is (ratio of long side / short side of particles). ) It is desirable that it is 10 or more.
[0079]
In such an antifouling coating composition, zinc oxide is contained in an amount of 1 to 1000 parts by weight, preferably 3 to 500 parts by weight, based on 100 parts by weight of the film-forming copolymer. It is usually contained in an amount of 5 to 65 parts by weight, preferably 8 to 55 parts by weight, and the scaly pigment is usually contained in an amount of 1 to 100 parts by weight, preferably 5 to 90 parts by weight. In such an antifouling coating composition, the antifouling agent is usually contained in an amount of 100 to 800 parts by weight, preferably 200 to 600 parts by weight, based on 100 parts by weight of the film-forming copolymer. It is desirable. When the scale pigment is in the range of 1 to 100 parts by weight, it is possible to form an antifouling coating film that is excellent in the additive effect, excellent in the antifouling effect, and particularly excellent in crack resistance.
[0080]
In general, it is considered that if a scaly pigment is blended in an antifouling paint composition or the like, it is effective in improving the crack resistance of the resulting coating film. However, in the conventional antifouling paint, when a scaly pigment having no physiological activity is blended, elution of the antifouling agent from the obtained antifouling coating is prevented, and the antifouling effect is greatly reduced. There was a problem with it. However, the antifouling coating film formed from the silyl ester antifouling coating composition (AF) excellent in self-polishing property (consumable) as in the present invention has excellent surface renewability in seawater, Even if scaly pigment is present on the surface of the film, it has sufficient renewability of the coating film, and the antifouling activity is originally at a very high level, so excessive elution of the antifouling agent is controlled and kept within an appropriate range. In addition, the occurrence of cracks after submergence can be more efficiently suppressed while (controlling).
[0081]
The antifouling paint composition, wherein the film-forming copolymer is a copolymer of (meth) acrylic acid tributylsilyl ester [TBS (M) A] and methyl (meth) acrylate [M (M) A] An example of an antifouling coating film made of is described in more detail. In seawater, hydroxide ions (OH^-The tributylsiloxy group (Bu) in the film-forming copolymer_ThreeSiO—) breaks from the carbonyl group (—CO—) bonded to the copolymer main chain, and tributylsilanol (Bu_ThreeIt becomes SiOH) and dissolves in seawater. On the other hand, the polymer constituting the main chain also has a carboxylate structure (—COO^-), The contact surface of the antifouling coating film with the seawater (the antifouling coating film surface) is considered to be renewed one after another. For this reason, the antifouling agent contained in the antifouling coating film is promptly released from the antifouling coating film surface. However, when the scaly pigment is contained in the paint as described above, contact between seawater and the antifouling agent and the film-forming copolymer is suppressed. It seems that will be obtained.
[0082]
The antifouling paint composition according to the present invention contains the above (meth) acrylic acid ester polymer and scaly pigment in addition to the above-mentioned film-forming copolymer, zinc oxide and chlorinated paraffin. May be.
[0083]
In such an antifouling coating composition, zinc oxide is contained in an amount of 1 to 1000 parts by weight, preferably 3 to 500 parts by weight, based on 100 parts by weight of the film-forming copolymer.
The chlorinated paraffin is usually contained in an amount of 3 to 200 parts by weight, preferably 5 to 100 parts by weight, more preferably 10 to 100 parts by weight,
The (meth) acrylic acid ester-based polymer is usually contained in an amount of 1 to 200 parts by weight, preferably 5 to 100 parts by weight, more preferably 10 to 100 parts by weight. It is desirable that it is contained in an amount of ˜400 parts by weight, preferably 1 to 200 parts by weight, more preferably 5 to 150 parts by weight. In such an antifouling coating composition, the antifouling agent is usually contained in an amount of 100 to 2000 parts by weight, preferably 150 to 1500 parts by weight, based on 100 parts by weight of the film-forming copolymer. It is desirable that
[0084]
[Dehydrating agent]
In addition, the antifouling coating composition containing a dehydrating agent can further improve the storage stability. As such a dehydrating agent, anhydrous gypsum (CaSO_Four), Synthetic zeolite-based adsorbents (trade name: molecular sieve, etc.), orthoesters such as methyl orthoformate and methyl orthoacetate, orthoborate esters, silicates and isocyanates (trade name: additive TI), etc. Anhydrous gypsum and molecular sieve are preferable, and molecular sieve is particularly preferably used. Such dehydrating agents can be used alone or in combination of two or more. The molecular sieve is more preferably used than anhydrous gypsum for the following reasons. That is, when an antifouling paint composition containing anhydrous gypsum is applied, water-soluble hydrated gypsum precipitates on the surface of the coating film during sweating or raining after application, causing whitening of the coating film. In addition, when further overcoating the surface of the antifouling coating film, there is a tendency to affect the overcoating property. Therefore, in order to avoid these, it is particularly preferable to use a molecular sieve.
[0085]
Further, in relation to such a dehydrating agent, the present invention will be described in more detail while comparing with the coating composition described in JP-A-7-18216. Since a relatively low molecular weight copolymer is contained as a functional copolymer, thickening gelation during storage is suppressed to some extent even in an antifouling coating composition not containing the dehydrating agent. In addition, even if the antifouling coating composition is somewhat thickened during long-term storage and has a tendency to gel, the antifouling coating composition is diluted with an appropriately selected solvent to If it can be applied, the formed coating film has wearability (self-polishing property) and good antifouling property is recognized. Even a coating film formed by applying an antifouling coating composition that has been thickened and gelled in this way has a consumable property, mainly in the amount described above. This is probably because a low molecular weight film-forming copolymer is used.
[0086]
On the other hand, in the coating composition described in JP-A-7-18216, when no dehydrating agent is blended, a remarkable tendency to thicken and gel is observed during storage of the coating composition. In a coating film formed by applying a coating composition thickened and gelled to the bottom of a ship or the like, wearability is hardly recognized and the antifouling property is poor.
[0087]
Such a dehydrating agent is usually used in an amount of 0.1 to 200 parts by weight, preferably 1 to 100 parts by weight, based on 100 parts by weight of the film-forming copolymer.
[Anti-sagging / anti-settling agent, pigment, etc.]
The anti-sagging / anti-settling agent may be blended in an arbitrary amount other than those that impair the storage stability of the antifouling paint composition such as organic clay. Such anti-sagging and anti-settling agents include Al, Ca, Zn stearate salts, lecithin salts, alkyl sulfonate salts, polyethylene wax, amide wax, hydrogenated castor oil wax system, polyamide wax system. And a mixture of both, synthetic finely divided silica, oxidized polyethylene wax, and the like. Preferably, hydrogenated castor oil wax, polyamide wax, synthetic finely divided silica, and oxidized polyethylene wax are used. Examples of such anti-sagging and anti-settling agents include those marketed under trade names such as “Dispalon 305” and “Dispalon 4200-20” manufactured by Enomoto Kasei Co., Ltd.
[0088]
As the pigment, in addition to the scaly pigment (eg, mica powder), various conventionally known organic and inorganic pigments (eg, titanium white, bengara) can be used. Various colorants such as dyes may also be included.
[0089]
As the solvent, for example, various solvents such as aliphatic, aromatic (e.g., xylene, toluene, etc.), ketone, ester, ether, and the like that are usually blended in antifouling paints are used.
[0090]
The antifouling paint composition as described above is applied to the surface of underwater structures (eg, water supply / drainage outlets of nuclear power plants) or various marine civil engineering facilities such as gulf roads, submarine tunnels, port facilities, canals and waterways. If it is applied to the surface of a sludge diffusion prevention film for construction, or the surface of various molded products such as ships and fishing gear (eg ropes, fishing nets) one or more times according to conventional methods, it will be exposed to dry conditions. Or anti-fouling coating coated hulls or underwater structures with excellent resistance to cracking and stability over time, such as in the vicinity of the waterline where immersion in water and exposure to air are repeated. can get. The antifouling paint composition according to the present invention may be applied directly to the surface of the above-mentioned hull or underwater structure, or a hull or underwater structure to which a base material such as a rust preventive or primer has been applied in advance. You may apply | coat to the surface of these. Furthermore, the antifouling of the present invention is used for repair on the surface of a hull, underwater structure or the like that has already been coated with a conventional antifouling paint or is coated with the antifouling paint composition of the present invention. The coating composition may be overcoated. Thus, although the thickness of the antifouling coating film formed on the surface of a hull, an underwater structure, etc. is not specifically limited, For example, it is about 30-150 micrometers / time.
[0091]
【The invention's effect】
Such an antifouling coating composition according to the present invention is particularly excellent in crack resistance and peeling resistance under drying such as being exposed to air, and is stable over time (that is, repeatedly dried due to fluctuations in the waterline). It is possible to form a coating film that is less likely to change over time and has long-term stability) by being exposed to the bottom or immersed in water.
[0092]
In particular, in addition to the film-forming copolymer and zinc oxide, the book further contains the chlorinated paraffin, (meth) acrylic acid ester polymer, dehydrating agent, antifouling agent (excluding zinc oxide), etc. In addition to the above effects, the antifouling paint composition of the invention is further excellent in physical properties such as peel resistance to a base material such as a ship bottom or a primer layer, and also excellent in antifouling properties and self-polishing properties (consumability). The antifouling coating film can be formed, and it is excellent in storage stability.
[0093]
【Example】
EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples. In the following examples and comparative examples, “part” means “part by weight”. In addition, the amount of each component in the table, for example, the amount of copolymer component, the amount of chlorinated paraffin (salt para), the amount of coloring pigment, cuprous oxide, zinc white, or the amount of solvent (eg, xylene) Unless otherwise indicated, all are indicated by “parts by weight”.
[Example of polymer production]
(Production of copolymer S-1)
A reaction vessel equipped with a stirrer, a condenser, a thermometer, a dropping device, and a heating / cooling jacket was charged with 100 parts of xylene and heated and stirred at a temperature of 90 ° C. under a nitrogen stream.
[0094]
While maintaining the same temperature, a mixture of 40 parts of tributylsilyl methacrylate, 60 parts of methyl methacrylate and 1.2 parts of 2,2′-azobisisobutyronitrile as a polymerization initiator was added to the reactor from the dropping device for 4 hours. It was dripped over.
[0095]
Thereafter, stirring was continued for 4 hours at the same temperature to obtain a colorless and transparent copolymer solution S-1.
The heating residue after heating the obtained copolymer solution S-1 at 105 ° C. for 3 hours was 49.9% by weight, and 95% by weight or more of each monomer was determined from the quantification result of the residual monomer by GPC. Incorporated in the polymer, the polymerization rate change during the reaction is almost the same for each monomer, and each component unit derived from these monomers is considered to be randomly arranged at the ratio of the amount of monomer used. It is done.
[0096]
The glass transition temperature (Tg) of the copolymer (heating residue) S-1 in the copolymer solution S-1 is 51 ° C., and the viscosity of the copolymer solution S-1 at 25 ° C. is 295 cps. Yes, the number average molecular weight (Mn) by GPC measurement was 11,200, and the weight average molecular weight (Mw) was 21,200.
(Production of Copolymer S-2 to Copolymer S-6)
Copolymer S-2, Copolymer S-3, Copolymer in the same manner as described above except that the dripping components were changed as shown in Table 1 during the production of Copolymer S-1. S-4, copolymer S-5, and copolymer S-6 were obtained, and the physical properties of these copolymers (solutions) were measured in the same manner as described above.
[0097]
The results are also shown in Table 1.
[0098]
[Table 1]

[0099]
Types and physical properties of compatible (meth) acrylic acid ester polymer component (solution) used in constituting the antifouling coating composition [heating residue (% by weight / polymer solution) and the polymer component The viscosity (Gardner / 25 ° C.), molecular weight (Mn: measured by GPC), acid value (AV), glass transition temperature (Tg ° C.)] of the compatible (meth) acrylic acid ester polymer contained in .
[0100]
The results are shown in Table 2.
[0101]
[Table 2]

[0102]
[Reference Example 1, Example 2, Reference Examples 3-6, Reference Examples 8-14, Examples 15-31,Comparative Examples 1 to
7 and 9]
[Production example of antifouling paint composition]Each antifouling coating composition having the composition shown in Tables 4 to 11 was produced (each component amount is expressed in parts by weight).
[0103]
When producing the antifouling paint compositions having the composition shown in Tables 4 to 11, these composition components were shaken together in a paint shaker containing glass beads for 2 hours and then aged at room temperature for 12 hours. Went. Next, the mixture was filtered through a 100 mesh filter to obtain a desired antifouling paint composition.
[0104]
The viscosities immediately after production (Ku value / 25 ° C.) measured with a Stormer viscometer for the antifouling coating composition and the viscosities after storage for 1 month at room temperature are also shown in Tables 12-14.
Further, the antifouling property, the degree of wear over time, the physical properties at alternating wet and dry parts, and the coating strength were evaluated using the antifouling coating composition as follows.
[0105]
The results are shown in Tables 12-14.
[Evaluation of antifouling properties]
A 70 × 200 × 3 mm sandblast plate that was bent so as to be attached to the side of a rotating drum installed in the seawater of Hiroshima Bay was prepared. To this sandblast plate, epoxy zinc rich primer (zinc powder content 80% by weight in dry coating film), tar epoxy anticorrosive paint, vinyl binder coat so that the dry film thicknesses become 20 μm, 150 μm and 50 μm, respectively. Then, the test antifouling paint composition was applied so that the film thickness after drying was 200 μm to obtain a test plate.
[0106]
After mounting this test plate on a rotating drum and simulating the operation of a ship for 12 months under a peripheral speed of 15 knots and 50% operating conditions (alternate operation of 12 hours at night and 12 hours during the day), antifouling properties (dynamic Anti-fouling property, adhesion area% of various aquatic organisms to the test plate), and degree of wear μ (thickness reduction: star column in the table).
[0107]
In addition, the degree of wear over time, the physical properties at alternating wet and dry parts, and the coating strength were also evaluated under the following conditions.
[Evaluation of wear over time]
After coating an epoxy zinc rich primer (with a zinc powder content of 80% in the dry coating film) on a disc-shaped sandblast plate with a diameter of 300 mm and a thickness of 3 mm, the dry film thickness is 20 μm, The tar-epoxy anticorrosion paint was applied so that the dry film thickness was 150 μm, and then left for another day, and further, a vinyl-based binder coat was applied in order so that the dry film thickness was 50 μm. Then, it was dried indoors for 7 days.
[0108]
Thereafter, a test antifouling coating composition was applied radially in the radial direction using an applicator having a clearance of 500 μm to obtain a test plate.
Attach this test plate to a motor in a thermostatic bath containing 25 ° C seawater, rotate at a peripheral speed of 15 knots under 100% operating conditions (continuous operation day and night), and wear rate around the circumference (thickness reduction) ) Was measured 4 times every 3 months.
[Evaluation of physical properties in alternating wet and dry parts]
A 70 mm × 150 mm × 2.3 mm sandblast plate was coated in the same manner as the coating method used in “Evaluation of antifouling properties” to obtain a test plate.
[0109]
This test plate is attached to a rotary dry alternating test machine that repeats 12 hours of immersion in seawater and 12 hours of exposure in the air. After the test machine has been operated for 3 months, the physical properties of the test plate are evaluated visually. Went.
[0110]
The evaluation criteria are as follows.
5: No crack or peeling on the surface of the test plate.
4: A slight crack is recognized on the test plate surface.
3: Fine cracks are observed on the surface of the test plate.
2: Remarkable cracking is observed on the surface of the test plate.
1: Remarkable cracking with peeling is observed on the surface of the test plate.
[Evaluation of coating strength]
A tar-epoxy anticorrosive paint is applied to a 70mm x 150mm x 2.3mm sandblast plate so that the dry film thickness is 150 µm, and then placed for 1 day. It was coated to 50 μm and then dried in a 40 ° C. incubator for 2 days.
[0111]
Next, a vinyl binder coat was further applied to the surface of the dry film so that the dry film thickness was 50 μm.
On the next day, the test antifouling paint composition was applied so that the dry film thickness was 150 μm, and the same antifouling paint composition was applied on the next day with a dry film thickness of 150 μm ( Total dry film thickness of antifouling paint composition: 150 + 150 = 300 μm).
[0112]
Then, it was dried for 14 days in a constant temperature / humidity chamber with a temperature of 20 ° C. and a humidity of 75%.
A 50 mm × 50 mm polyethylene sheet was placed on the coating film surface of the test plate thus obtained, and a 30 mm × 30 mm simulated board was placed on top of it, 30 kg / cm.²After pressurizing with a load of 30 minutes, the damage of the coating film was visually evaluated.
[0113]
The evaluation criteria are as follows.
[0114]
[Table 3]

[0115]
The said evaluation result is collectively shown to Tables 12-14.
In addition, the component names in the table are as follows.
▲ 1 ▼ “Toyo Parax 150”
Chlorinated paraffin manufactured by Tosoh Corporation, average carbon number: 14.5, chlorine content (amount) 50%, viscosity: 12 poise / 25 ° C., specific gravity: 1.25 / 25 ° C.
▲ 2 ▼ “Toyoparax A-40”
Chlorinated paraffin manufactured by Tosoh Corporation, average carbon number: 24.5, chlorine content (amount) 40.5%, viscosity: 18.5 poise / 25 ° C, specific gravity: 1.16 / 25 ° C.
▲ 3 ▼ “Toyoparax 270”
Chlorinated paraffin manufactured by Tosoh Corporation, average carbon number: 12, chlorine content (amount) 70%, viscosity: 4 poise / 80 ° C., specific gravity: 1.50 / 80 ° C.
▲ 4 ▼ “Toyoparax A-70”
Chlorinated paraffin manufactured by Tosoh Corporation, average carbon number: 24.5, chlorine content (amount) 70%, white powder, specific gravity: 1.65 / 25 ° C.
▲ 5 ▼ "Molecular sieve 4A"
Dehydrating agent, Union Showa Co., Ltd., synthetic zeolite powder.
▲ 6 ▼ "Disparon 305"
A hydrogenated castor oil-based sagging agent manufactured by Enomoto Kasei Co., Ltd.
▲ 7 ▼ “Disparon 4200-20”
Polyethylene oxide anti-settling agent, 20% xylene paste, manufactured by Enomoto Kasei Co., Ltd.
(8) “Mica Shiratama”: Scale pigment made by (Yes) (Wakimoto Mica), average particle size: 15 μm, aspect ratio: 40.
[0116]
In the table, “chlorinated paraffin (% by weight) (to copolymer)”, “Cu₂The calculation method of “O (wt%) (copolymer, ie, film-forming copolymer, the same shall apply hereinafter)”, “ZnO (wt%) (copolymer)” and the like are as follows.
[0117]
For example, in the “antifouling paint composition P-1”, “salt para (chlorinated paraffin) content (% by weight) (to copolymer)” = 30.8 is determined as follows.
That is, in the “antifouling paint composition P-1”, chlorinated paraffin is blended in an amount of 4 parts by weight, and “copolymer component (solution) S-1” is blended in an amount of 26 parts by weight. In addition, 26 parts by weight of the “copolymer component (solution) S-1” contains 49.9% by weight of the residual residue (copolymer S-1). Therefore, in the “antifouling paint composition P-1”, “chlorinated paraffin (% by weight) (to copolymer)” = [4 / {26 × 49.9 / 100}] × 100% = 30.8 (% By weight).
[0118]
[Table 4]

[0119]
[Table 5]

[0120]
[Table 6]

[0121]
[Table 7]

[0122]
[Table 8]

[0123]
[Table 9]

[0124]
[Table 10]

[0125]
[Table 11]

[0126]
[Table 12]

[0127]
[Table 13]

[0128]
[Table 14]

Claims (12)

It has a component unit derived from a trialkylsilyl ester of a polymerizable unsaturated carboxylic acid in an amount of 20 to 65% by weight, has a number average molecular weight of 3000 to 20000, a weight average molecular weight of 4000 to 150,000, and a glass transition point of 25 to 25. A film-forming copolymer having a viscosity (25 ° C., CPS) in a 50% xylene solution at 80 ° C. of 40 to 1000;
Zinc oxide ,
A (meth) acrylic acid ester-based polymer having a number average molecular weight of 1000 to 100,000 which is compatible with the film-forming copolymer ,
The zinc oxide is contained in an amount of 1-1000 parts by weight with respect to 100 parts by weight of the film-forming copolymer ,
An antifouling paint composition comprising the (meth) acrylic acid ester polymer in an amount of 5 to 200 parts by weight . It has a component unit derived from a trialkylsilyl ester of a polymerizable unsaturated carboxylic acid in an amount of 20 to 65% by weight, a number average molecular weight of 3000 to 20000, a weight average molecular weight of 4000 to 150,000, and a glass transition point of 25 to 25. A film-forming copolymer having a viscosity (25 ° C., CPS) in a 50% xylene solution at 80 ° C. of 40 to 1000 ;
Zinc oxide,
A (meth) acrylic acid ester polymer having a number average molecular weight of 1000 to 100,000 which is compatible with the film-forming copolymer,
Chlorinated paraffin and
The zinc oxide is contained in an amount of 1-1000 parts by weight with respect to 100 parts by weight of the film-forming copolymer,
The (meth) acrylic ester polymer is contained in an amount of 5 to 200 parts by weight,
An antifouling paint composition comprising the chlorinated paraffin in an amount of 5 to 150 parts by weight. It has a component unit derived from a trialkylsilyl ester of a polymerizable unsaturated carboxylic acid in an amount of 20 to 65% by weight, has a number average molecular weight of 3000 to 20000, a weight average molecular weight of 4000 to 150,000, and a glass transition point of 25 to 25. Viscosity in xylene solution at 80 ° C. (2
A film-forming copolymer having a temperature of 5 ° C. and a CPS of 40 to 1000 ;
Zinc oxide,
A (meth) acrylic acid ester polymer having a number average molecular weight of 1000 to 100,000 which is compatible with the film-forming copolymer ,
Chlorinated paraffin ,
Comprising a dehydrating agent,
For 100 parts by weight of the film-forming copolymer,
The zinc oxide is contained in an amount of 1-1000 parts by weight,
The (meth) acrylic acid ester polymer is contained in an amount of 1 to 200 parts by weight,
The chlorinated paraffin is contained in an amount of 3 to 200 parts by weight,
An antifouling paint composition comprising the dehydrating agent in an amount of 0.1 to 200 parts by weight. The antifouling paint according to any one of claims 1 to 3, wherein at least one of the three alkyl groups bonded to the silicon atom of the trialkylsilyl ester has 3 or more carbon atoms. Composition. The antifouling paint composition according to any one of claims 1 to 3, wherein the trialkylsilyl ester is tributylsilyl (meth) acrylate. 4. The antifouling paint composition according to claim 2 , wherein the chlorinated paraffin has an average carbon number of 8 to 30 and a chlorine content of 35 to 75%. A (meth) acrylic acid ester polymer having a number average molecular weight of 1000 to 100,000 which is compatible with the film-forming copolymer is a hydrophobic (meth) acrylic acid ester homopolymer, two or more ( meth) acrylic acid copolymer ester and (meth) at least one member selected from the group consisting of acrylic ester-styrene copolymer (meth) of claim 1 is an acrylic acid ester polymer The antifouling paint composition according to any one of the above. Claim 1 said film forming copolymer and compatible possible number average molecular weight of 1,000 to 100,000 glass transition temperature of the (meth) acrylate ester polymer (Tg) of at 0 ℃ or higher The antifouling paint composition described in 1. The antifouling paint composition according to any one of claims 1 to 3, further comprising an antifouling agent (excluding zinc oxide). A coating film formed from the antifouling paint composition according to any one of claims 1 to 9 . An antifouling method for a hull or underwater structure, wherein the antifouling paint composition according to any one of claims 1 to 9 is used. A hull or underwater structure characterized in that the surface of the hull or underwater structure is coated with a coating film comprising the antifouling paint composition according to any one of claims 1 to 9 .