JP2004251100A - Method for coating ceramic tile wall surface - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating method to prevent deterioration of a ceramic-tile wall surface. <P>SOLUTION: A water-repelling agent (A) which contains emulsion of alkylalkoxysilane (a), organopolysiloxane having alkoxy group (b), alkoxysilane having aminoalkyl group (c1) and/or organopolysiloxane having aminoalkyl group (c2) and emulsifier (d) as active ingredients is painted on the ceramic tiles and/or joints of the ceramic tiles. Furthermore, a clear paint or a coating agent exhibiting photocatalytic activity is applied. The clear paint is preferable to contain either photo-curable resin with maleimide group as resin component or organosilicate compound. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【００１２】
（式中Ｒは、場合によりハロゲン置換されていてもよい、同じか又は異なる炭素数が１〜２０のアルキル基を表し、Ｒ^１は、同じか又は異なる炭素数が１〜６のアルキル基を表し、ｘは０≦ｘ≦３、好ましくは０．６≦ｘ≦１．８の数値を表し、ｙは０≦ｙ≦３、好ましくは０．０１≦ｙ≦２．０の数値を表し、ｚは、０≦ｚ≦３の数値を表す。ただしｘ、ｙ及びｚの合計は、３．５以下である。）。
【００１３】
炭素数が１〜２０のアルキル基、及び炭素数が１〜６のアルコキシ基としては、上記アルキルアルコキシシラン（ａ）の説明で列記したものと同様のものが使用できる。
【００１４】
上記オルガノポリシロキサン（ｂ）は、例えば、メチルトリクロロシラン及び場合により炭素数が１〜８のアルキルトリクロロシラン又はフェニルトリクロロシランとエタノールとを水中で反応させることによって得ることができる。
【００１５】
アミノアルキル基を有するアルコキシシラン（ｃ１）は、下記一般式（ＩＩ）で示されるものが挙げられる。
Ｒ^２ _ａＲ^３ _ｂＳｉ（ＯＲ^４）_{４−ａ−ｂ} （ＩＩ）
（式中Ｒ^２は、ハロゲン置換されてもよい、同じか異なる炭素数が１〜２０のアルキル基、好ましくはメチル基であり、Ｒ^３は、ハロゲン置換されてもよい同じか又は異なる炭素数１〜３０のアミノアルキル基を表し、Ｒ^４は、同じか又は異なる炭素数が１〜６のアルキル基または水素原子を表し、ａは０≦ａ≦２である数値、ｂは、１≦ｂ≦３である数値、ただしａ及びｂの合計は３以下である）。
【００１６】
Ｒ^２はＲと同様のものが使用できる。Ｒ^３基として好ましいアミノアルキル基としては、Ｈ_２ＮＣＨ_２−、Ｈ_２Ｎ（ＣＨ_２）_２−、Ｈ_２Ｎ（ＣＨ_２）_３−、Ｈ_２Ｎ（ＣＨ_２）_２ＮＨ（ＣＨ_２）_２−、Ｈ_２Ｎ（ＣＨ_２）_２ＮＨ（ＣＨ_２）_３−、Ｈ_３ＣＮＨ（ＣＨ_２）_３−、Ｃ_２Ｈ_５ＮＨ（ＣＨ_２）_３−、Ｈ_３ＣＮＨ（ＣＨ_２）_２−、Ｃ_２Ｈ_５ＮＨ（ＣＨ_２）_２−、Ｈ_２Ｎ（ＣＨ_２）_４−、Ｈ_２Ｎ（ＣＨ_２）_５−、Ｈ（ＮＨＣＨ_２ＣＨ_２）_３−、Ｃ_４Ｈ_９ＮＨ（ＣＨ_２）_２ＮＨ（ＣＨ_２）_２−、シクロヘキシル−ＮＨ（ＣＨ_２）_３−、シクロヘキシル−ＮＨ（ＣＨ_２）_２−、（ＣＨ_３）_２Ｎ（ＣＨ_２）_３−、（ＣＨ_３）_２Ｎ（ＣＨ_２）_２−、（Ｃ_２Ｈ_５）_２Ｎ（ＣＨ_２）_３−、及び（Ｃ_２Ｈ_５）_２Ｎ（ＣＨ_２）_３−基等が挙げられる。
【００１７】
アミノアルキル基を有するオルガノポリシロキサン（ｃ２）は、分岐状構造を有し、下記一般式（ＩＩＩ）で表されるものが好適に使用できる。
【００１８】
【化２】

【００１９】
（式中Ｒ^５は、Ｒと同様のものを表し、Ｒ^６は、Ｒ^３と同様のものを表し、Ｒ^７は、Ｒ^１と同様のものを表し、かつｃは０≦ｃ≦１の数値を表し、ｄは０≦ｄ≦３の数値を表し、ｅは０≦ｅ≦３の数値を表し、ただし、ｃ、ｄ及びｅの合計は３以下である。）。
【００２０】
特にＲ^５はメチル基、Ｒ^６はアミノプロピル基又は（アミノエチル）アミノプロピル基、Ｒ^７はメチル又はエチル基が好適である。
【００２１】
上記アミノアルキル基を有するオルガノポリシロキサン（ｃ２）は、上記アミノアルキル基を有するアルコキシシラン（ｃ１）と、アルコキシ基及び／又はヒドロキシル基を有しかつ塩基性窒素を含まないオルガノポリシロキサンとを平衡させるか又は縮合させることによって製造することができる。
【００２２】
乳化剤（ｄ）としては、アニオン性乳化剤、カチオン性乳化剤、ノニオン性乳化剤、両性乳化剤等従来公知のものが制限なく使用できるが、特にノニオン性乳化剤が好ましく、例えばアルキルポリグリコールエーテル、アルキルアリールポリグリコールエーテル、アルキルアミンとエチレンオキシド又はプロピレンオキシドとの付加生成物、アルキルポリグリコシド、ポリビニルアルコールが好ましい。
【００２３】
本発明方法に使用される撥水処理剤（Ａ）に含有されるエマルションは、上記アルキルアルコキシシラン（ａ）、オルガノポリシロキサン（ｂ）、アミノアルキル基を有するアルコキシシラン（ｃ１）及びアミノアルキル基を有するオルガノポリシロキサン（ｃ２）を水、及び乳化剤（ｄ）にて乳化してなるものである。
【００２４】
乳化方法としては定法により乳化する。例えば、先ず水の一部分のみを乳化剤（ｄ）と混合し、次に成分（ｂ）、（ｃ１）及び／又は（ｃ２）を加え、次に成分（ａ）を入れて乳化し、次いで残りの水を入れて希釈する。また成分（ａ）、（ｂ）及び成分（ｃ１）及び／又は（ｃ２）を混合し、これを乳化剤（ｄ）及び水の混合物に加えてもよい。乳化は好ましくは圧力乳化機、コロイドミル高速ステーターローター撹拌機中で行う。
【００２５】
上記撥水処理剤（Ａ）は有効成分として、さらにケイ素樹脂、フッ素含有ポリマー、ポリオレフィンワックス、シリコンワックス、ポリウレタン、アクリル、ポリエステル、エポキシ等の有機ポリマーおよびその分散体、顔料、光触媒活性を有する酸化チタン、分散剤、表面張力調整剤、充填剤、増粘剤、緩衝物質、殺カビ剤、殺菌剤、殺藻剤、殺菌薬、香料、防腐剤、及び消泡剤も含有することができる。
【００２６】
上記撥水処理剤（Ａ）は、通常、水性媒体によって有効成分の濃度を１〜２０％、さらには３〜１５％の範囲に調整して塗装することが好適である。該水性媒体とは、水、あるいは水に溶解可能な有機溶剤を包含する。
【００２７】
塗布量は、有効成分の塗布量が、１〜２０ｇ／ｍ^２、好ましくは３〜１５ｇ／ｍ^２の範囲となるように塗布することが望ましい。水性媒体による希釈後の撥水処理剤（Ａ）の塗布量としては、０．０５〜０．２Ｋｇ／ｍ^２／回、好ましくは０．０７〜０．１５Ｋｇ／ｍ^２／回の範囲が適当である。有効成分の塗布量を上記範囲の如く確保するために、希釈後の撥水処理剤（Ａ）を上記塗布量／回の範囲で、複数回塗り重ねても良い。
【００２８】
その塗装手段は特には限定されないが、例えばスプレー塗り、ローラー塗り、刷毛塗り、流し塗り等の手段で行うことができる。
【００２９】
塗装方法としては、磁器タイル面及び該磁器タイルの目地部を共に塗装する方法、磁器タイル目地部にのみ塗装する方法が挙げられる。本発明方法に適用される撥水処理剤（Ａ）によれば、磁器タイル面及び該目地部共に濡れ色となることもなく、撥水性を付与することができるが、防水性を特に要求される目地部のみに塗装してもよい。例えば、上記塗装手段により目地部のみを選択して塗装してもよいが、磁器タイル面及び該磁器タイルの目地部共に上記手段にて塗装し、該磁器タイルの目地部に該処理剤（Ａ）を含侵させた後、磁器タイル面に塗布された処理剤（Ａ）を除去する方法等が挙げられる。磁器タイル面に塗布された処理剤（Ａ）を除去する方法としては、該表面を拭く、散水処理等の手段が挙げられる。このように撥水処理剤（Ａ）の目地部に対する含浸度が磁器タイル自体の含浸度より大きいことを利用して、上記のごとく磁器タイル目地部にのみ撥水処理剤（Ａ）を塗布することができる。
【００３０】
本発明方法においては、上記撥水処理剤（Ａ）にて磁器タイル面及び／又は該磁器タイル目地部を処理した後、さらに従来公知のシリコン系、ジルコニウム系の撥水処理剤を上記塗装方法により重ねて塗装してもよい。
【００３１】
次工程として上記した従来の撥水処理剤もしくは後述のクリヤー塗料（Ｂ）もしくは光触媒活性を有する酸化チタンを含有する塗布剤（Ｃ）を、撥水処理剤（Ａ）の塗面上に塗り重ねる場合において、該撥水処理剤（Ａ）塗装後の乾燥は、例えば、２０℃の乾燥温度では約２時間から１０日間の範囲であることが好適である。
【００３２】
本発明方法は、上記方法で撥水処理剤（Ａ）を塗装した後、さらにクリヤー塗料（Ｂ）を塗装する塗装工法を提供する。
【００３３】
かかるクリヤー塗料（Ｂ）としては、従来公知のクリヤー塗料を使用することができる。
【００３４】
ビヒクル成分となる樹脂成分としては、従来公知の架橋、もしくは非架橋タイプの樹脂が挙げられ、例えばアクリル樹脂、アクリルシリコン樹脂、ポリエステル樹脂、シリコン樹脂、フッ素樹脂、ウレタン樹脂等が挙げられる。また、これらを適宜組み合わせて変性してなる樹脂、または混合してなる樹脂も包含される。
【００３５】
クリヤー塗料（Ｂ）としては、例えば上記に例示の樹脂成分を水性媒体または有機溶剤（例えば、芳香族系、エステル系、ケトン系、アルコール系、エーテル系、脂肪族炭化水素系などこれらを単独でまたは２種以上組み合わせた有機溶剤等）に溶解、または分散したものを使用することができる。
【００３６】
本発明方法においては、上記樹脂成分として、マレイミド基を有する光硬化型樹脂を使用することが望ましい。マレイミド基は光の照射により２量化することのできる官能基であり、これを含む樹脂は光硬化をすることができる。光源としては太陽光等の自然光であってもよく、屋外における塗膜形成過程において硬化が進行するので、貯蔵安定性と硬化性が両立することが可能である。
【００３７】
マレイミド基の導入方法としては、例えばマレイミド基を有する重合性不飽和モノマーとその他のモノマーを共重合する方法が挙げられる。本発明においてクリヤー塗料（Ｂ）がマレイミド基を含有することにより、クリヤー塗膜が汚れ難いという利点がある。
【００３８】
また、クリヤー塗膜の表面を降雨水等により経時で親水化させ、クリヤー塗膜に耐汚染性を付与させるために、上記クリヤー塗料（Ｂ）が、オルガノシリケート化合物を包含することが望ましい。そのような目的で使用しうるオルガノシリケート化合物としては、例えば、下記一般式（ＩＶ）で表される化合物を挙げることができる。
【００３９】
【化３】

【００４０】
式中、Ｒ^８は同じか又は異なり、水素原子又は炭素数１〜１０のアルキル基である。例えば、メチル基、エチル基、ｎ−プロピル基、イソ−プロピル基、ｎ−ブチル基、ｉ−ブチル基、ｔ−ブチル基、ｎ−ペンチル基、イソ−ペンチル基、ｎ−ヘキシル基、イソ−ヘキシル基、ｎ−オクチル基等の直鎖又は分岐状のアルキル基や、フェニル基などのアリール基が好適である。
【００４１】
しかして、上記式（ＩＶ）のオルガノシリケート化合物の具体例としては、例えば、テトラヒドロキシシラン、テトラメトキシシラン、テトラエトキシシラン、テトラプロポキシシラン、テトラブトキシシラン、テトラフェノキシシラン、ジメトキシジエトキシシランなどが挙げられる。これらはそれぞれ単独で又は２種以上組み合わせて用いることができる。
【００４２】
また、上記オルガノシリケート化合物同士の分岐状もしくは直鎖状の縮合物も使用することもでき、その縮合度は通常２〜１００の範囲内が適当である。
【００４３】
また、クリヤー塗料が水系である場合には、オルガノシリケート化合物として、上記のオルガノシリケート化合物及び／又はその縮合物中のアルコキシ基又は水酸基にポリアルキレングリコール系化合物を一部反応させた変性オルガノシリケート化合物が水に対する溶解性が良好であり、好適に使用できる。
【００４４】
変性剤としてのポリアルキレングリコール系化合物としては、一般式（Ｖ）
Ｒ^９Ｏ−（Ｒ^{１ ０}Ｏ）ｎ−Ｈ （Ｖ）
式中、Ｒ^９は水素原子、アルキル基又はアリール基であり、Ｒ^１０は炭素数２〜４のアルキレン基であり、ｎは２〜６０である、で表わされるものが挙げられる。具体的には、例えば、ポリエチレングリコール、ポリプロピレングリコール、ポリテトラメチレングリコールなどのポリアルキレングリコール；メトキシポリエチレングリコール、エトキシポリエチレングリコール、エトキシポリプロピレングリコール、エトキシポリブチレングリコールなどのアルコキシポリアルキレングリコール；ポリオキシエチレンノニルフェニルエーテル、ポリオキシエチレンオクチルフェニルエーテルなどのポリオキシアルキレンアルキルフェニルエーテル等が挙げられ、特にポリエチレングリコール、ポリオキシエチレンノニルフェニルエーテルが好適である。
【００４５】
上記オルガノシリケート化合物の含有量は、クリヤー塗料（Ｂ）の樹脂固形分１００重量部あたり一般に０．１〜５０重量部、好ましくは１〜２０重量部の範囲内が好適である。
【００４６】
上記クリヤー塗料（Ｂ）は、樹脂固形分が通常２０〜６０重量％、特に３０〜５０重量％の範囲が適当であり、また、塗布量は約０．０５〜０．１２Ｋｇ／ｍ^２／回、好ましくは０．０８〜０．ｌ０Ｋｇ／ｍ^２／回の範囲が好ましい。クリヤー塗料の乾燥塗膜厚は１０〜１００μｍ、好ましくは２０〜７０μｍの範囲が好適である。この乾燥塗膜厚を得るために上記塗布量の範囲で複数回塗り重ねても良い。この塗装手段は特に限定はされないが、例えばスプレー塗り、ローラー塗り、刷毛塗り、流し塗りなどの手段で行うことができる。塗布量がこの範囲を下回ると塗膜の保護能力が低下し、この範囲を超えると目地部が濡れ色となることがある。
【００４７】
上記クリヤー塗料（Ｂ）を使用した本発明に従う塗装工法によれば、目地部内部に撥水処理剤（Ａ）が含浸され、目地部内部は撥水性となり防水性が向上し、かつ磁器タイル壁面の表面は、クリヤー塗膜により保護され、さらに低汚染性を発現させることもできる。
【００４８】
本発明は、撥水処理剤（Ａ）を塗装した後、さらに光触媒活性を有する酸化チタンを含有する塗布剤（Ｃ）を塗装する塗装工法を提供する。
【００４９】
上記光触媒活性を有する酸化チタンは、バンド・ギャップを有する半導体粒子であり、そのバンド・ギャップ以上のエネルギ−を持つ光（例えば太陽光や人工照明光の紫外線等）が照射されると光励起により生成した電子と正孔が半導体粒子表面に移動し、その強い酸化能力によってこれに接する汚染物質などを分解する機能を発揮するものである。該酸化チタンには正方晶系に属するルチル型、アナタ−ゼ型と、斜方晶系に属するブルッカイト型の３種類の結晶型があるが、光触媒活性を有する酸化チタンとしては通常、アナタ−ゼ型の酸化チタンである。
【００５０】
上記塗布剤（Ｃ）における光触媒活性を有する酸化チタン以外の成分としては、シリコン樹脂等の無機系樹脂等のビヒクル成分や各種添加剤、希釈剤等が挙げられる。また、塗布剤（Ｃ）としては、上記光触媒活性を有する酸化チタンを変性させることにより得られるコロイド状水分散物を主成分とする塗布剤も包含される。
【００５１】
塗布剤（Ｃ）の塗布量は、該塗布剤（Ｃ）の固形分が、０．１〜１０ｇ／ｍ^２、好ましくは０．３〜５ｇ／ｍ^２の範囲となるように塗布することが望ましい。
【００５２】
この塗装手段は特に限定はされないが、例えばスプレー塗り、ローラー塗り、刷毛塗り、流し塗りなどの手段で行うことができる。磁器タイル面及び該磁器タイル目地部共に塗装してもよいし、磁器タイル面及び該磁器タイルの目地部共に上記手段にて塗装し、該磁器タイルの目地部に該塗布剤（Ｃ）を含侵させた後、磁器タイル面に塗布された塗布剤（Ｃ）を例えば上記で説明した方法で除去する方法にて塗装してもよい。
【００５３】
上記塗布剤（Ｃ）を使用した本発明に従う塗装工法によれば、目地部内部に撥水処理剤（Ａ）が含浸され、目地部内部は撥水性となり防水性が向上し、目地部表面には光触媒層を形成することが出来、内部は防水性を維持しながら表面は、低汚染性、汚染物質分解性等の光触媒活性を発現することが可能である。
【００５４】
【実施例】
以下、実施例を挙げて本発明をさらに詳細に説明する。尚、文中「部」及び「％」は、それぞれ「重量部」及び「重量％」を意味する。
【００５５】
撥水処理剤（Ａ）の製造
製造例１〜５
下記表１に示す各成分を下記に示す配合組成で混合し、高速ステーターローター攪拌装置で乳化した後、有効成分濃度が１０％になるようにさらに水で希釈して撥水処理剤（Ａ１）〜（Ａ５）を得た。
【００５６】
【表１】

【００５７】
（注１）アルキルアルコキシシラン（ａ１）：イソオクチルトリエトキシシラン
（注２）アルキルアルコキシシラン（ａ２）：ｎ−ヘキシルトリメトキシシラン
（注３）アルコキシ基を有するオルガノポリシロキサン（ｂ１）：平均分子量７６０ｇ／モルを有する実験式（ＣＨ_３）_０．７（イソオクチル）_０．３Ｓｉ（ＯＣＨ_３）_１．３Ｏ_０．８５で示される化合物
（注４）アルコキシ基を有するオルガノポリシロキサン（ｂ２）：平均分子量６５０ｇ／モルを有する実験式ＣＨ_３Ｓｉ（ＯＣ_２Ｈ_５）_０．８Ｏ_１．１で示される化合物
（注５）アミノアルキル基を有するアルコキシシラン（ｃ１）：Ｎ−（２−アミノエチル）−３−アミノプロピルトリメトキシシラン
（注６）アミノアルキル基を有するオルガノポリシロキサン（ｃ２）：ＫＯＨの存在下でアルコキシ基を有するオルガノポリシロキサン（ｂ１）およびアミノアルキル基を有するアルコキシシラン（ｃ１）から製造される、アミン価約３．０、粘度約５００ｍｍ^２／ｓ（２５℃）及びＮ−（２−アミノエチル）−３−アミノプロピルトリメトキシシラン中に初めに存在するメトキシ基を基準にして５モル％未満の残余メトキシ基を有する縮合生成物
（注７）乳化剤（ｄ１）：イソトリデシルアルコール−（１６）−ポリグリコールエーテル。
【００５８】
クリヤー塗料（Ｂ）の製造
製造例６
攪拌機、温度計、滴下ロート、窒素導入管を付設した２Ｌフラスコに、酢酸ブチル９００ｇ、メチルメタクリレート２２０ｇ、ｎ−ブチルメタクリレート４４ｇ、ｎブチルアクリレート８７ｇ、ヒドロキシエチルメタクリレート５８ｇ、下記式で表されるマレイミド基含有メタクリレート８７ｇ、メタクリル酸５ｇを仕込み、十分窒素置換をおこなった後、７５℃まで昇温した。フラスコの内温が７５℃に到達した時点で、アゾビスイソブチロニトリル５ｇを酢酸ブチル１００ｇに溶解した開始剤溶液を滴下し、重合を開始した。その後、メチルメタクリレート２２０ｇ、ｎ−ブチルメタクリレート４４ｇ、ｎ−ブチルアクリレート８７ｇ、ヒドロキシエチルメタクリレート５８ｇ、下記式で表されるマレイミド基含有メタクリレート８７ｇ、メタクリル酸５ｇにアゾイソブチロニトリル５ｇを溶解させたモノマー混合物を該フラスコに３時間かけて滴下した。その後、温度を８５℃に昇温して２時間熟成し、更に９０℃で２時間熟成させた。
【００５９】
その後、フラスコの内容物を多量のメタノールに沈殿させ、９９９ｇ（重合率９９．７％）、水酸基価５０ｍｇＫＯＨ／ｇ、酸価６．５ｍｇＫＯＨ／ｇの重合体を得た。該重合体を固形分４０％になるようにキシレン／酢酸ブチル＝５０／５０（重量比）に溶解すると、無色透明な溶液が得られた。得られた重合体溶液１００部に硬化剤として「コロネートＨＸ」（商品名、日本ポリウレタン（株）製、イソシアネート硬化剤）を水酸基価／ＮＣＯ価＝１．０になるように７．３部、硬化促進剤として、ジブチル錫ジラウレートの０．１ｗｔ％キシレン溶液を２．９部加え、マレイミド基を有する光硬化型樹脂を樹脂成分として含有するクリヤ塗料（Ｂ１）を調製した。
【００６０】
【化４】

【００６１】
製造例７
「アレスレタンクリヤ−」（商品名、関西ペイント社製、アクリル樹脂／イソシアネ−ト硬化型有機溶剤系塗料）の樹脂固形分１００部に対して、「エチルシリケート４０」（商品名、コルコ−ト社製、テトラエチルシリケ−ト縮合物）の固形分が２０部となるように配合し、オルガノシリケート含有クリヤ（Ｂ２）を調整した。
【００６２】
試験基板の調整
スレート板に１０ｃｍ角磁器タイルを縦横２個ずつエポキシ接着剤を使用して貼り付け、その際に各磁器タイル間の目地幅を２ｍｍとした。この目地に目地モルタル（ダントーメジフィット、ダントー株式会社製）をタイル表面より２ｍｍ低くなるように埋め込み、１４日間養生して磁器タイルパネル試験基板とした。
【００６３】
実施例１
上記試験基板の表面全体に上記撥水処理剤（Ａ１）を刷毛にて、塗布量が１００ｇ／ｍ^２／回となるように塗装し、常温で７日間乾燥させて試験体を得た。
実施例２〜５
実施例１において、撥水処理剤（Ａ１）の変わりに撥水処理剤（Ａ２）〜（Ａ５）を夫々使用する以外は実施例１と同様にして各試験体を得た。
実施例６
試験基板の表面全体に上記製造例で得た撥水処理剤（Ａ１）を刷毛にて、塗布量が１００ｇ／ｍ^２／回となるように塗装し、目地モルタル面に塗装した撥水処理剤を染み込ませた後に磁器タイル表面の撥水処理剤（Ａ１）のみをウエスで拭き取って、常温で７日間乾燥させて試験体を得た。
実施例７
試験基板の表面全体に上記製造例で得た撥水処理剤（Ａ１）を刷毛にて、塗布量が１００ｇ／ｍ^２／回となるように塗装し、目地モルタル面に塗装した撥水処理剤を十分染み込ませた後に試験基板表面に散水し、磁器タイル表面の撥水処理剤のみを洗い流した後、常温で７日間乾燥させて実施例７の試験体を得た。
実施例８
実施例１と同様に撥水処理剤（Ａ１）を塗装した後、常温で１日乾燥させ、さらに、クリヤー掛け工程として、「アクアプリズム」（商品名、関西ペイント社製、水性シリコン系クリヤー塗料、固形分４５％）を刷毛にて塗布量１００ｇ／ｍ^２／回となるように１回塗装し、常温で７日間乾燥させて試験体を得た。
実施例９
実施例６と同様に撥水処理剤（Ａ１）を塗装して磁器タイル表面の撥水処理剤のみを除去した後、常温で１日乾燥させ、さらに、クリヤー掛け工程として、「アクアプリズム」（商品名、関西ペイント社製、水性シリコン系クリヤー塗料、固形分４５％）を刷毛にて塗布量１００ｇ／ｍ^２／回となるように１回塗装し、常温で７日間乾燥させて実施例９の試験体を得た。
【００６４】
実施例１０
実施例７と同様に撥水処理剤（Ａ１）を塗装して磁器タイル表面の撥水処理剤のみを除去した後、常温で１日乾燥させ、さらに、クリヤー掛け工程として、「アクアプリズム」（商品名、関西ペイント社製、水性シリコン系クリヤー塗料、固形分４５％）を刷毛にて塗布量１００ｇ／ｍ^２／回となるように１回塗装し、常温で７日間乾燥させて実施例１０の試験体を得た。
実施例１１
実施例６と同様に撥水処理剤（Ａ１）を塗装して磁器タイル表面の撥水処理剤のみを除去した後、常温で１日乾燥させ、さらに、クリヤー掛け工程としてマレイミド基を有する光硬化型樹脂を樹脂成分として含有するクリヤー塗料（Ｂ１）を刷毛にて塗布量１００ｇ／ｍ^２／回となるように１回塗装し、常温で７日間乾燥させて実施例１１の試験体を得た。
実施例１２
実施例６と同様に撥水処理剤（Ａ１）を塗装して磁器タイル表面の撥水処理剤のみを除去した後、常温で１日乾燥させ、さらに、クリヤー掛け工程としてオルガノシリケート含有クリヤー塗料（Ｂ２）を刷毛にて塗布量１００ｇ／ｍ^２／回となるように１回塗装し、常温で７日間乾燥させて実施例１２の試験体を得た。
実施例１３
実施例６と同様に撥水処理剤（Ａ１）を塗装して磁器タイル表面の撥水処理剤のみを除去した後、常温で１日乾燥させ、さらに、「ＴＫＣ−３０４」（商品名、テイカ株式会社製、アナターゼ型光触媒酸化チタンの水性ディスパージョン、固形分濃度９％）を刷毛にて塗布量が３０ｇ／ｍ^２／回となるように１回塗装し、常温で７日間乾燥させて実施例１２の試験体を得た。
【００６５】
比較例１
試験基板の表面全体に「セラシリコンタイルコーティング材」（商品名、関西ペイント株式会社製、アクリルシリコン樹脂系クリヤー塗料）を１００ｇ／ｍ^２塗装し、常温で１日間乾燥させた後、該セラシリコンタイルコーティング材を６０ｇ／ｍ^２塗装し、常温で７日間乾燥させて比較例１の試験体を得た。
比較例２
試験基板の表面全体に、ヘキシルトリメトキシシランをトルエンで１０％に希釈したものを塗布量が１００ｇ／ｍ^２／回となるように塗装し、常温で７日間乾燥させて比較例２の試験体を得た。
比較例３
試験基板の表面全体に、オルガチックスＺＢ−３２０（松本製薬工業社製、有効成分（Ｃ_４Ｈ_９Ｏ）_３Ｚｒ（ＯＣＯＣ_１７Ｈ_３５））をトルエンで１０％に希釈したものを塗布量が１００ｇ／ｍ^２／回となるように塗装し、常温で７日間乾燥させて比較例２の試験体を得た。
【００６６】
得られた各試験体について下記の試験方法に基づいて試験を行った。試験結果を下記表２に示す。
【００６７】
【表２】

【００６８】
（＊１）初期外観の濡れ色
各試験体の目地モルタル部分の色を塗装していない目地モルタルと比較して、下記の基準で判定した。
◎：試験体と塗装していない目地モルタル部分とで見分けがつかない
○：試験体と塗装していない目地モルタル部分とでほとんど見分けがつかない
△：試験体の色が塗装していない目地モルタル部分よりやや濃い
×：試験体の色が塗装していない目地モルタル部分よりはっきり濃い
（＊２）水接触角
各試験体目地部表面に水滴を滴下し、角度測定器で各試験体表面と水滴の境界の角度（水接触角）を測定した。値が大きいほど表面が撥水性であることを示している。
（＊３）サンシャインウェザーメーター試験後の水接触角
各試験体をＪＩＳ Ｂ７７５３ に規定される試験機（サンシャインウェザーメーター）に１０００時間暴露した後の水接触角を測定した。暴露前後で水接触角の変化が少ないほど良好であることを示す。
（＊４）付着性
上記の促進試験終了後、各試験体の磁器タイル面および目地モルタル面にカッターナイフで素地に達するまでクロスカットを入れた後、粘着テープを貼り付けてはがし、下記の基準で判定した。
◎：全く剥離しない
○：クロスカットにそって若干の剥離がある
△：はっきりした剥離がある
×：全面剥離
（＊５）耐汚染性
各試験体を１年間の屋外曝露試験を行った後、試験体の目視評価をし、下記の基準で判定した。
◎：ほとんど汚れが目立たない
○：わずかに汚れが分かる
△：汚れが目立つ
×：汚れが著しい
【００６９】
【発明の効果】
本発明の塗装工法によれば、磁器タイルと目地部という性質の異なる素材が組み合わされた素材である磁器タイル壁面の保護方法として、特定の撥水処理剤を塗装することにより、磁器タイル面の質感を損なうことなく、磁器タイル目地部の防水性を向上させることができる。また、磁器タイル自体にも撥水性を付与することができる。目地部には該撥水処理剤が内部奥深くに含浸されているので、クリヤー塗料や光触媒を含有する塗布剤の塗装により目地部が濡れ色となることもなく、内部は防水性、表層は低汚染性、光触媒活性等の機能を付与させることも可能であり、磁器タイル壁面の美観を長期にわたって維持することができる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a coating method for preventing deterioration of a wall surface of a porcelain tile used for an exterior material of a building and maintaining the appearance.
[0002]
2. Description of the Related Art
Porcelain tiles are widely used, for example, as interior and exterior materials for buildings, because they have excellent durability and a unique aesthetic appearance due to their good color and gloss. The finishing method using such a porcelain tile has many advantages, but has a problem that joints provided between the porcelain tiles are apt to deteriorate due to long-term exposure. For example, mortar used for joints between porcelain tiles, due to long-term exposure, the neutralization etc. lowers the waterproofness, as a result, water enters the back of the porcelain tile, and the porcelain tile layer deteriorates, In some cases, problems such as dropping of porcelain tiles occurred. As a countermeasure, Patent Literature 1 proposes a method of applying an alkoxysilyl group-containing acrylic resin-based paint to porcelain tiles and joints, and then applying a specific clear paint.
[Patent Document 1] JP-A-8-290107
However, this method has a problem in that the joints and some porcelain tiles change to a dark color and a "wet color" phenomenon occurs, which impairs the appearance. Patent Document 2 proposes a method of applying a silicon-based or zirconium-based water-repellent agent to joints.
[Patent Document 2] JP-A-2001-347221
However, this method has a problem that although the wetting color phenomenon is alleviated, the water repellency persistence becomes insufficient. In addition, the porcelain tile wall is made of a combination of materials that are completely different from each other in the properties of porcelain tiles and joints, so that both materials retain their texture and have good adhesion and water repellency. Development was required.
[0003]
[Means for Solving the Problems]
The present inventors have conducted intensive studies to solve the above problems, and as a result, have an alkylalkoxysilane, an organopolysiloxane having an alkoxy group, and an aminoalkyl group on the porcelain tile surface and / or joint portions of the porcelain tile. By applying a specific water-repellent agent containing an emulsion containing an organopolysiloxane having an alkoxysilane and / or an aminoalkyl group and an emulsifier as an active ingredient, it is possible to improve the aesthetic maintenance and durability of the entire porcelain tile wall surface. As a result, the present invention has been completed.
That is, the present invention
1. An alkylalkoxysilane (a), an organopolysiloxane having an alkoxy group (b), an alkoxysilane having an aminoalkyl group (c1) and / or an aminoalkyl group are provided on the surface of the porcelain tile and / or at the joints of the porcelain tile. A method of coating a wall of a porcelain tile, which comprises applying a water-repellent agent (A) containing an emulsion containing an organopolysiloxane (c2) and an emulsifier (d) as active ingredients;
2. After applying the water-repellent agent (A) to the porcelain tile surface and the joints of the porcelain tile, the water-repellent agent (A) applied to the porcelain tile surface is removed. Painting method,
3. 3. A method of coating a porcelain tile wall by applying a water repellent treatment agent (A) by the method described in 1 or 2 and then further applying a clear paint (B).
4. 4. The method for coating a porcelain tile wall according to item 3, wherein the clear paint (B) contains a photocurable resin having a maleimide group as a resin component.
5. The method for coating a porcelain tile wall according to item 3 or 4, wherein the clear coating material (B) contains an organosilicate compound,
6. A method for coating the wall of a porcelain tile, in which after applying the water-repellent treatment agent (A) by the method described in item 1 or 2, further applying a coating agent (C) containing titanium oxide having photocatalytic activity,
7.1 A porcelain tile wall surface finished by the coating method according to any one of Items 1 to 6;
About.
[0004]
BEST MODE FOR CARRYING OUT THE INVENTION
The wall of the porcelain tile to which the method of the present invention is applied is composed of a porcelain tile and joints. In the case of new construction, after sufficient curing, in the case of repair, the surface of the porcelain tile is cleaned using a cleaning solution containing a detergent or acid. It is preferable that the resin is sufficiently removed, washed with water, dried, and then provided for painting.
[0005]
The porcelain tile is usually obtained by melting and sintering a mixture of a porcelain earth at a high temperature, and is mainly composed of, for example, a clay material, feldspar and silica stone.
[0006]
On the other hand, the joint portion is usually made of mortar, that is, a cementitious material and sand, and is desirably dried to a moisture content of 10% by weight or less, preferably 8% by weight or less before painting. Thereby, there is an advantage that the joint part is easily impregnated with the water repellent treatment agent (A) of the present invention.
[0007]
The water-repellent treating agent (A) used in the method of the present invention includes an alkylalkoxysilane (a), an organopolysiloxane having an alkoxy group (b), an alkoxysilane having an aminoalkyl group (c1) and / or an aminoalkyl group. And an emulsion containing an organopolysiloxane (c2) having the formula (1) and an emulsifier (d) as active ingredients.
[0008]
In the above alkylalkoxysilane (a), examples of the alkyl group include a linear / branched, alicyclic aliphatic alkyl group and an aromatic alkyl group, and the alkyl group is fluorine, chlorine, bromine or the like. And a halogen atom such as iodine. In the method of the present invention, an alkyl group having 1 to 20 carbon atoms is preferable. As the alkyl group, for example, a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, an iso- Butyl, t-butyl, n-pentyl, iso-pentyl, neo-pentyl, t-pentyl, n-hexyl, n-heptyl, n-octyl, iso-octyl, 2, 2,4-trimethylpentyl group, n-nonyl group, n-decyl group, linear or branched alkyl group such as n-dodecyl group, cyclopentyl group, cyclohexyl group, 4-ethylcyclohexyl group, cycloheptyl group, Cycloalkyl groups such as norbornyl group and methylcyclohexenyl group; vinyl group, allyl group, n-5-hexenyl group, 4-vinylcyclohexenyl group and 3-norbo Alkenyl groups such as enyl group; aryl groups such as phenyl group, biphenylyl group, naptyl group, anthryl group and phenanthryl group; alkaryl groups such as o-, m-, p-tolyl group, xylyl group and ethylphenyl group; And aralkyl groups such as benzyl group, α- and β-phenylethyl groups. Among these, an unsubstituted alkyl group having 1 to 12 carbon atoms and a phenyl group are preferred.
[0009]
As the alkoxy group, an alkoxy group having 1 to 6 carbon atoms is preferable, for example, methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, tert-butoxy group, pentyl An oxy group, a hexyloxy group and the like can be mentioned. The alkoxy group may be substituted by a halogen atom.
[0010]
The organopolysiloxane (b) having an alkoxy group in the present invention has a branched structure, and examples thereof include those represented by the following general formula (I).
[0011]
Embedded image

[0012]
(Wherein R represents an alkyl group having 1 to 20 carbon atoms which may be optionally substituted with halogen, and¹Represents the same or different alkyl group having 1 to 6 carbon atoms, x represents a value of 0 ≦ x ≦ 3, preferably 0.6 ≦ x ≦ 1.8, y represents 0 ≦ y ≦ 3, Preferably, it represents a numerical value of 0.01 ≦ y ≦ 2.0, and z represents a numerical value of 0 ≦ z ≦ 3. However, the sum of x, y and z is not more than 3.5. ).
[0013]
As the alkyl group having 1 to 20 carbon atoms and the alkoxy group having 1 to 6 carbon atoms, those similar to those listed in the description of the alkylalkoxysilane (a) can be used.
[0014]
The organopolysiloxane (b) can be obtained, for example, by reacting methyltrichlorosilane and optionally an alkyltrichlorosilane or phenyltrichlorosilane having 1 to 8 carbon atoms with ethanol in water.
[0015]
Examples of the alkoxysilane (c1) having an aminoalkyl group include those represented by the following general formula (II).
R² _aR³ _bSi (OR⁴)_4-ab    (II)
(Where R²Is an alkyl group having 1 to 20 carbon atoms, which may be substituted by halogen, preferably a methyl group,³Represents the same or different aminoalkyl group having 1 to 30 carbon atoms which may be substituted with halogen,⁴Represents the same or different alkyl group having 1 to 6 carbon atoms or a hydrogen atom, a is a numerical value satisfying 0 ≦ a ≦ 2, b is a numerical value satisfying 1 ≦ b ≦ 3, provided that the sum of a and b Is 3 or less).
[0016]
R²Can be the same as R. R³Preferred aminoalkyl groups include H₂NCH₂-, H₂N (CH₂)₂-, H₂N (CH₂)₃-, H₂N (CH₂)₂NH (CH₂)₂-, H₂N (CH₂)₂NH (CH₂)₃-, H₃CNH (CH₂)₃-, C₂H₅NH (CH₂)₃-, H₃CNH (CH₂)₂-, C₂H₅NH (CH₂)₂-, H₂N (CH₂)₄-, H₂N (CH₂)₅-, H (NHCH₂CH₂)₃-, C₄H₉NH (CH₂)₂NH (CH₂)₂-, Cyclohexyl-NH (CH₂)₃-, Cyclohexyl-NH (CH₂)₂−, (CH₃)₂N (CH₂)₃−, (CH₃)₂N (CH₂)₂−, (C₂H₅)₂N (CH₂)₃-, And (C₂H₅)₂N (CH₂)₃-Groups and the like.
[0017]
The organopolysiloxane (c2) having an aminoalkyl group has a branched structure, and those represented by the following general formula (III) can be suitably used.
[0018]
Embedded image

[0019]
(Where R⁵Represents the same as R, and R⁶Is R³Represents the same as⁷Is R¹And c represents a numerical value of 0 ≦ c ≦ 1, d represents a numerical value of 0 ≦ d ≦ 3, e represents a numerical value of 0 ≦ e ≦ 3, where c, d and The sum of e is 3 or less. ).
[0020]
Especially R⁵Is a methyl group, R⁶Is an aminopropyl group or an (aminoethyl) aminopropyl group, R⁷Is preferably a methyl or ethyl group.
[0021]
The organopolysiloxane (c2) having an aminoalkyl group is obtained by equilibrating the alkoxysilane (c1) having an aminoalkyl group with the organopolysiloxane having an alkoxy group and / or a hydroxyl group and containing no basic nitrogen. Or by condensation.
[0022]
As the emulsifier (d), conventionally known emulsifiers such as anionic emulsifier, cationic emulsifier, nonionic emulsifier, and amphoteric emulsifier can be used without any limitation. Nonionic emulsifiers are particularly preferable, for example, alkyl polyglycol ether and alkylaryl polyglycol. Preferred are ethers, addition products of alkylamines with ethylene oxide or propylene oxide, alkyl polyglycosides, and polyvinyl alcohol.
[0023]
The emulsion contained in the water-repellent treating agent (A) used in the method of the present invention comprises the above-mentioned alkylalkoxysilane (a), organopolysiloxane (b), alkoxysilane (c1) having an aminoalkyl group and aminoalkyl group. Is obtained by emulsifying an organopolysiloxane (c2) having water and an emulsifier (d).
[0024]
Emulsification is carried out by a conventional method. For example, first only a portion of the water is mixed with the emulsifier (d), then the components (b), (c1) and / or (c2) are added, then the component (a) is added and emulsified, then the remaining Dilute with water. Alternatively, the components (a) and (b) and the components (c1) and / or (c2) may be mixed and added to a mixture of the emulsifier (d) and water. The emulsification is preferably carried out in a pressure emulsifier, a colloid mill high speed stator rotor stirrer.
[0025]
The water-repellent agent (A) may further contain, as an active ingredient, a silicon resin, a fluorine-containing polymer, a polyolefin wax, a silicone wax, an organic polymer such as polyurethane, acrylic, polyester, or epoxy, a dispersion thereof, a pigment, and an oxidation having photocatalytic activity. Titanium, dispersants, surface tension modifiers, fillers, thickeners, buffer substances, fungicides, bactericides, algicides, bactericides, fragrances, preservatives, and defoamers can also be included.
[0026]
It is preferable that the water-repellent agent (A) is usually applied by adjusting the concentration of the active ingredient to 1 to 20%, more preferably 3 to 15%, with an aqueous medium. The aqueous medium includes water or an organic solvent soluble in water.
[0027]
The coating amount is such that the coating amount of the active ingredient is 1 to 20 g / m.², Preferably 3 to 15 g / m²It is desirable to apply so as to fall within the range of The coating amount of the water repellent treatment agent (A) after dilution with the aqueous medium is 0.05 to 0.2 kg / m²/ Time, preferably 0.07 to 0.15 kg / m²/ Time range is appropriate. In order to secure the applied amount of the active ingredient within the above range, the diluted water repellent treatment agent (A) may be applied and applied a plurality of times within the range of the above applied amount / time.
[0028]
The coating means is not particularly limited, but can be applied by means of, for example, spray coating, roller coating, brush coating, flow coating and the like.
[0029]
Examples of the coating method include a method of coating both the porcelain tile surface and the joint of the porcelain tile, and a method of coating only the porcelain tile joint. According to the water-repellent treatment agent (A) applied to the method of the present invention, water repellency can be imparted without causing a wet color on the porcelain tile surface and the joints, but waterproofness is particularly required. May be applied only to the joints. For example, only the joints may be selected and painted by the above-mentioned painting means. However, the porcelain tile surface and the joints of the porcelain tile are painted by the above-mentioned means, and the treatment agent (A) is applied to the joints of the porcelain tile. ) And then removing the treating agent (A) applied to the porcelain tile surface. Examples of a method for removing the treatment agent (A) applied to the porcelain tile surface include a method such as wiping the surface and water spraying. As described above, the water repellent agent (A) is applied only to the porcelain tile joint portion by utilizing the fact that the degree of impregnation of the joint portion of the water repellent agent (A) is larger than that of the porcelain tile itself. be able to.
[0030]
In the method of the present invention, after the porcelain tile surface and / or the porcelain tile joint is treated with the above-mentioned water-repellent treatment agent (A), a conventionally known silicon-based or zirconium-based water-repellent treatment agent is further coated with the above-mentioned coating method. May be applied repeatedly.
[0031]
As the next step, the above-mentioned conventional water-repellent agent or a clear paint (B) described later or a coating agent (C) containing titanium oxide having photocatalytic activity is applied over the surface of the water-repellent agent (A). In this case, the drying after the application of the water-repellent treatment agent (A) is preferably, for example, at a drying temperature of 20 ° C. for about 2 hours to 10 days.
[0032]
The method of the present invention provides a coating method in which the water repellent treatment agent (A) is applied by the above method, and then the clear coating material (B) is applied.
[0033]
As the clear paint (B), a conventionally known clear paint can be used.
[0034]
Examples of the resin component serving as the vehicle component include a conventionally known crosslinked or non-crosslinked resin, such as an acrylic resin, an acrylic silicone resin, a polyester resin, a silicone resin, a fluororesin, and a urethane resin. In addition, a resin obtained by modifying the above components in an appropriate combination or a resin obtained by mixing them is also included.
[0035]
As the clear paint (B), for example, the resin components exemplified above may be used alone or in an aqueous medium or an organic solvent (eg, aromatic, ester, ketone, alcohol, ether, aliphatic hydrocarbon, etc.). Or a solution dissolved or dispersed in an organic solvent or the like in which two or more kinds are combined).
[0036]
In the method of the present invention, it is desirable to use a photocurable resin having a maleimide group as the resin component. A maleimide group is a functional group that can be dimerized by light irradiation, and a resin containing the same can be photocured. The light source may be natural light such as sunlight, and the curing proceeds during the coating film formation process outdoors, so that both storage stability and curability can be achieved.
[0037]
Examples of a method for introducing a maleimide group include a method of copolymerizing a polymerizable unsaturated monomer having a maleimide group with another monomer. In the present invention, when the clear coating (B) contains a maleimide group, there is an advantage that the clear coating film is hardly stained.
[0038]
In order to make the surface of the clear coating film hydrophilic over time with rainwater or the like, and to impart stain resistance to the clear coating film, the clear coating material (B) desirably contains an organosilicate compound. Examples of the organosilicate compound that can be used for such a purpose include a compound represented by the following general formula (IV).
[0039]
Embedded image

[0040]
Where R⁸Are the same or different and are a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. For example, methyl, ethyl, n-propyl, iso-propyl, n-butyl, i-butyl, t-butyl, n-pentyl, iso-pentyl, n-hexyl, iso- A straight-chain or branched alkyl group such as a hexyl group and an n-octyl group, and an aryl group such as a phenyl group are preferred.
[0041]
Thus, specific examples of the organosilicate compound of the above formula (IV) include, for example, tetrahydroxysilane, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, tetraphenoxysilane, dimethoxydiethoxysilane and the like. No. These can be used alone or in combination of two or more.
[0042]
In addition, a branched or linear condensate of the above-mentioned organosilicate compounds can also be used, and the condensation degree is usually suitably in the range of 2 to 100.
[0043]
When the clear coating is water-based, a modified organosilicate compound obtained by partially reacting a polyalkylene glycol-based compound with an alkoxy group or a hydroxyl group in the above-mentioned organosilicate compound and / or a condensate thereof is used as the organosilicate compound. Has good solubility in water and can be suitably used.
[0044]
As the polyalkylene glycol-based compound as a modifier, a compound represented by the general formula (V)
R⁹O- (R^{1 0}O) n-H (V)
Where R⁹Is a hydrogen atom, an alkyl group or an aryl group;¹⁰Is an alkylene group having 2 to 4 carbon atoms, and n is 2 to 60. Specifically, for example, polyalkylene glycols such as polyethylene glycol, polypropylene glycol and polytetramethylene glycol; alkoxypolyalkylene glycols such as methoxy polyethylene glycol, ethoxy polyethylene glycol, ethoxy polypropylene glycol and ethoxy polybutylene glycol; polyoxyethylene nonyl Examples thereof include polyoxyalkylene alkyl phenyl ethers such as phenyl ether and polyoxyethylene octyl phenyl ether, and polyethylene glycol and polyoxyethylene nonyl phenyl ether are particularly preferable.
[0045]
The content of the organosilicate compound is generally in the range of 0.1 to 50 parts by weight, preferably 1 to 20 parts by weight, per 100 parts by weight of the resin solid content of the clear coating composition (B).
[0046]
The clear coating material (B) preferably has a resin solid content in the range of usually 20 to 60% by weight, particularly 30 to 50% by weight, and the coating amount is about 0.05 to 0.12 kg / m.²/ Times, preferably 0.08-0. 10Kg / m²/ Times is preferred. The dry coating thickness of the clear paint is preferably in the range of 10 to 100 μm, and more preferably 20 to 70 μm. In order to obtain this dry coating thickness, the coating may be applied a plurality of times within the range of the above-mentioned coating amount. The coating means is not particularly limited, but can be applied by means of, for example, spray coating, roller coating, brush coating, flow coating, or the like. If the coating amount is below this range, the protective ability of the coating film will be reduced, and if it exceeds this range, the joints may become wet.
[0047]
According to the coating method according to the present invention using the clear paint (B), the joint portion is impregnated with the water-repellent treatment agent (A), the joint portion becomes water-repellent, the waterproof property is improved, and the porcelain tile wall surface is improved. Surface is protected by a clear coating film, and furthermore, low contamination can be exhibited.
[0048]
The present invention provides a coating method in which a water repellent treatment agent (A) is applied, and then a coating agent (C) containing titanium oxide having photocatalytic activity is applied.
[0049]
The titanium oxide having photocatalytic activity is a semiconductor particle having a band gap, and is generated by photoexcitation when irradiated with light having energy equal to or larger than the band gap (for example, sunlight or ultraviolet light of artificial illumination light). The electrons and holes move to the surface of the semiconductor particles, and exert a function of decomposing contaminants and the like in contact with the semiconductor particles due to their strong oxidizing ability. The titanium oxide has three crystal types, a rutile type and an anatase type belonging to a tetragonal system, and a brookite type belonging to an orthorhombic system, and titanium oxide having photocatalytic activity is usually an anatase. Type titanium oxide.
[0050]
Components other than titanium oxide having photocatalytic activity in the coating agent (C) include vehicle components such as inorganic resins such as silicone resins, various additives, and diluents. The coating agent (C) also includes a coating agent containing a colloidal aqueous dispersion obtained by modifying the above-mentioned titanium oxide having photocatalytic activity as a main component.
[0051]
The coating amount of the coating agent (C) is such that the solid content of the coating agent (C) is 0.1 to 10 g / m², Preferably 0.3 to 5 g / m²It is desirable to apply so as to fall within the range of
[0052]
The coating means is not particularly limited, but can be applied by means of, for example, spray coating, roller coating, brush coating, flow coating, or the like. The porcelain tile surface and the porcelain tile joints may be painted together, or the porcelain tile surface and the porcelain tile joints may be painted by the above-mentioned means, and the joint agent of the porcelain tile contains the coating agent (C). After the infiltration, the coating agent (C) applied to the porcelain tile surface may be applied by, for example, a method of removing by the method described above.
[0053]
According to the coating method according to the present invention using the coating agent (C), the joint portion is impregnated with the water-repellent treatment agent (A), the joint portion becomes water-repellent, and the waterproof property is improved. Can form a photocatalytic layer, and the surface can exhibit photocatalytic activity such as low pollution and decomposability of pollutants while maintaining waterproofness inside.
[0054]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples. In the description, “parts” and “%” mean “parts by weight” and “% by weight”, respectively.
[0055]
Production of water repellent agent (A)
Production Examples 1 to 5
Each component shown in the following Table 1 was mixed in the following composition and emulsified by a high-speed stator rotor stirring device, and further diluted with water so that the active ingredient concentration became 10%, and a water-repellent treatment agent (A1) To (A5) were obtained.
[0056]
[Table 1]

[0057]
(Note 1) Alkylalkoxysilane (a1): isooctyltriethoxysilane
(Note 2) Alkylalkoxysilane (a2): n-hexyltrimethoxysilane
(Note 3) Organopolysiloxane having an alkoxy group (b1): empirical formula having an average molecular weight of 760 g / mol (CH₃)_0.7(Isooctyl)_0.3Si (OCH₃)_1.3O_0.85Compound represented by
(Note 4) Organopolysiloxane having an alkoxy group (b2): empirical formula CH having an average molecular weight of 650 g / mol.₃Si (OC₂H₅)_0.8O_1.1Compound represented by
(Note 5) Alkoxysilane having an aminoalkyl group (c1): N- (2-aminoethyl) -3-aminopropyltrimethoxysilane
(Note 6) Organopolysiloxane having an aminoalkyl group (c2): An amine value produced from an organopolysiloxane having an alkoxy group (b1) and an alkoxysilane having an aminoalkyl group (c1) in the presence of KOH. 3.0, viscosity about 500mm²/ S (25 ° C.) and condensation products having less than 5 mol% residual methoxy groups, based on the methoxy groups originally present in N- (2-aminoethyl) -3-aminopropyltrimethoxysilane
(Note 7) Emulsifier (d1): isotridecyl alcohol- (16) -polyglycol ether.
[0058]
Production of clear paint (B)
Production Example 6
In a 2 L flask equipped with a stirrer, thermometer, dropping funnel and nitrogen inlet tube, 900 g of butyl acetate, 220 g of methyl methacrylate, 44 g of n-butyl methacrylate, 87 g of n-butyl acrylate, 58 g of hydroxyethyl methacrylate, and a maleimide group represented by the following formula After 87 g of the contained methacrylate and 5 g of methacrylic acid were charged and sufficiently replaced with nitrogen, the temperature was raised to 75 ° C. When the internal temperature of the flask reached 75 ° C, an initiator solution obtained by dissolving 5 g of azobisisobutyronitrile in 100 g of butyl acetate was added dropwise to start polymerization. Thereafter, a monomer obtained by dissolving 5 g of azoisobutyronitrile in 220 g of methyl methacrylate, 44 g of n-butyl methacrylate, 87 g of n-butyl acrylate, 58 g of hydroxyethyl methacrylate, 87 g of a maleimide group-containing methacrylate represented by the following formula, and 5 g of methacrylic acid. The mixture was added dropwise to the flask over 3 hours. Thereafter, the temperature was raised to 85 ° C and aged for 2 hours, and further aged at 90 ° C for 2 hours.
[0059]
Thereafter, the contents of the flask were precipitated in a large amount of methanol to obtain a polymer having 999 g (polymerization rate of 99.7%), a hydroxyl value of 50 mgKOH / g, and an acid value of 6.5 mgKOH / g. When the polymer was dissolved in xylene / butyl acetate = 50/50 (weight ratio) so as to have a solid content of 40%, a colorless and transparent solution was obtained. To 100 parts of the obtained polymer solution, 7.3 parts of “Coronate HX” (trade name, manufactured by Nippon Polyurethane Co., Ltd., isocyanate curing agent) as a curing agent so that hydroxyl value / NCO value = 1.0, As a curing accelerator, 2.9 parts of a 0.1 wt% xylene solution of dibutyltin dilaurate was added, and a clear coating (B1) containing a photocurable resin having a maleimide group as a resin component was prepared.
[0060]
Embedded image

[0061]
Production Example 7
Ethyl silicate 40 (trade name, Corco Co., Ltd.) is used for 100 parts of resin solid content of "Aresle tank rear" (trade name, manufactured by Kansai Paint Co., Ltd., acrylic resin / isocyanate-curable organic solvent-based paint). The solid content of tetraethyl silicate condensate (manufactured by Tohoku Co., Ltd.) was adjusted to 20 parts to prepare an organosilicate-containing clear (B2).
[0062]
Test board adjustment
Two 10 cm square porcelain tiles were attached to the slate plate using an epoxy adhesive, two by two in the vertical and horizontal directions, and the joint width between the porcelain tiles was set to 2 mm. A joint mortar (Dantau Medifit, manufactured by Danto Corporation) was embedded in the joint so as to be lower than the tile surface by 2 mm and cured for 14 days to obtain a porcelain tile panel test substrate.
[0063]
Example 1
The above-mentioned water repellent treatment agent (A1) is applied to the entire surface of the test substrate with a brush by an amount of 100 g / m2.²/ Times, and dried at room temperature for 7 days to obtain a test body.
Examples 2 to 5
Each specimen was obtained in the same manner as in Example 1 except that the water-repellent agents (A2) to (A5) were used instead of the water-repellent agent (A1).
Example 6
Apply the water-repellent agent (A1) obtained in the above-mentioned production example to the entire surface of the test substrate with a brush at an application amount of 100 g / m2.²The test was conducted by applying the water repellent on the joint mortar surface and then wiping only the water repellent (A1) on the porcelain tile surface with a rag and drying at room temperature for 7 days. Got a body.
Example 7
Apply the water-repellent agent (A1) obtained in the above-mentioned production example to the entire surface of the test substrate with a brush at an application amount of 100 g / m2.²After applying the water-repellent treatment applied to the joint mortar surface sufficiently, water was sprayed on the test substrate surface, and only the water-repellent treatment agent on the porcelain tile surface was washed off, and then at room temperature for 7 days. The test piece of Example 7 was obtained by drying.
Example 8
After applying the water-repellent treatment agent (A1) in the same manner as in Example 1, it is dried at room temperature for one day, and as a clearing step, "Aqua Prism" (trade name, manufactured by Kansai Paint Co., Ltd., water-based silicone clear paint) , Solid content 45%) with a brush 100 g / m²/ Times, and dried at room temperature for 7 days to obtain test specimens.
Example 9
A water-repellent agent (A1) was applied in the same manner as in Example 6 to remove only the water-repellent agent on the surface of the porcelain tile, and then dried at room temperature for one day. Further, as a clearing step, "Aqua prism" ( Brand name, Kansai Paint Co., Ltd., water-based silicone clear paint, solid content 45%) applied with a brush 100 g / m²/ Times, and dried at room temperature for 7 days to obtain a specimen of Example 9.
[0064]
Example 10
A water-repellent agent (A1) was applied in the same manner as in Example 7 to remove only the water-repellent agent from the surface of the porcelain tile, and then dried at room temperature for one day. Further, as a clearing step, "Aqua prism" ( Brand name, Kansai Paint Co., Ltd., water-based silicone clear paint, solid content 45%) applied with a brush 100 g / m²/ Times, and dried at room temperature for 7 days to obtain a test sample of Example 10.
Example 11
A water-repellent agent (A1) was applied in the same manner as in Example 6 to remove only the water-repellent agent on the surface of the porcelain tile, dried at room temperature for one day, and then photocured with a maleimide group as a clearing step 100 g / m of clear paint (B1) containing a mold resin as a resin component with a brush²/ Times, and dried at room temperature for 7 days to obtain a test sample of Example 11.
Example 12
A water-repellent treatment agent (A1) was applied in the same manner as in Example 6 to remove only the water-repellent treatment agent on the surface of the porcelain tile, dried at room temperature for one day, and further subjected to an organosilicate-containing clear paint ( B2) is applied with a brush at a coating amount of 100 g / m.²/ Times, and dried at room temperature for 7 days to obtain a test body of Example 12.
Example 13
After coating the water repellent agent (A1) in the same manner as in Example 6 to remove only the water repellent agent on the surface of the porcelain tile, it is dried at room temperature for one day, and further, “TKC-304” (trade name, Teica) Aqueous dispersion of anatase type photocatalytic titanium oxide aqueous solution, solid content 9%, manufactured by Co., Ltd.²/ Times, and dried at room temperature for 7 days to obtain a test body of Example 12.
[0065]
Comparative Example 1
100 g / m of "cera silicon tile coating material" (trade name, clear paint of acrylic silicone resin, manufactured by Kansai Paint Co., Ltd.) on the entire surface of the test substrate²After painting and drying at room temperature for one day, the sera silicone tile coating material was applied at 60 g / m2.²The test piece of Comparative Example 1 was obtained by coating and drying at room temperature for 7 days.
Comparative Example 2
Hexyltrimethoxysilane diluted to 10% with toluene was applied to the entire surface of the test substrate at a coating amount of 100 g / m2.²/ Times and dried at room temperature for 7 days to obtain a test sample of Comparative Example 2.
Comparative Example 3
On the entire surface of the test substrate, Olgatics ZB-320 (Matsumoto Pharmaceutical Co., Ltd., active ingredient (C₄H₉O)₃Zr (OCOC₁₇H₃₅)) Was diluted to 10% with toluene, and the coating amount was 100 g / m2.²/ Times and dried at room temperature for 7 days to obtain a test sample of Comparative Example 2.
[0066]
A test was performed on each of the obtained test specimens based on the following test method. The test results are shown in Table 2 below.
[0067]
[Table 2]

[0068]
(* 1) Wet color of initial appearance
The color of the joint mortar portion of each test piece was compared with the unpainted joint mortar, and judged based on the following criteria.
◎: Indistinguishable between test specimen and unpainted joint mortar
：: Almost indistinguishable between test specimen and unpainted joint mortar
△: The color of the test specimen is slightly darker than the unpainted joint mortar
×: The color of the specimen is clearly darker than the unpainted joint mortar
(* 2) Water contact angle
A water drop was dropped on the joint surface of each test piece, and the angle (water contact angle) between the surface of each test piece and the water drop was measured with an angle measuring instrument. A higher value indicates that the surface is more water repellent.
(* 3) Water contact angle after sunshine weather meter test
The water contact angle was measured after each test piece was exposed to a tester (sunshine weather meter) specified in JIS B7753 for 1000 hours. The smaller the change in water contact angle before and after exposure, the better.
(* 4) Adhesiveness
After completion of the accelerated test, a cross cut was made on the porcelain tile surface and joint mortar surface of each test piece with a cutter knife until the base material was reached, and then an adhesive tape was attached and peeled off, and judgment was made according to the following criteria.
◎: Does not peel at all
：: slight peeling along the cross cut
△: Clear peeling
×: Peeling over the entire surface
(* 5) Stain resistance
After performing a one-year outdoor exposure test on each specimen, the specimen was visually evaluated and judged according to the following criteria.
：: Almost no dirt is noticeable
：: Slight dirt can be seen
Δ: Dirt is noticeable
×: Extremely dirty
[0069]
【The invention's effect】
According to the coating method of the present invention, as a method of protecting a porcelain tile wall surface, which is a material in which porcelain tiles and materials having different properties of joints are combined, a specific water-repellent agent is applied to coat the porcelain tile surface. The waterproof property of the porcelain tile joint can be improved without impairing the texture. Further, the porcelain tile itself can be provided with water repellency. Since the joint portion is impregnated with the water repellent agent deep inside, the joint portion does not become wet by coating with a clear paint or a coating agent containing a photocatalyst, the inside is waterproof, and the surface layer is low. It is also possible to impart functions such as contamination and photocatalytic activity, and it is possible to maintain the beautiful appearance of the porcelain tile wall surface for a long time.

Claims (7)

An alkylalkoxysilane (a), an organopolysiloxane having an alkoxy group (b), an alkoxysilane having an aminoalkyl group (c1) and / or an aminoalkyl group are provided on the surface of the porcelain tile and / or at the joints of the porcelain tile. A method for coating a porcelain tile wall, comprising applying a water-repellent agent (A) containing an emulsion containing an organopolysiloxane (c2) and an emulsifier (d) as active ingredients. After applying the water repellent agent (A) to both the porcelain tile surface and the joints of the porcelain tile, the water repellent agent (A) applied to the porcelain tile surface is removed. Painting method. A method for coating a porcelain tile wall, wherein the water repellent treatment agent (A) is applied by the method according to claim 1 or 2, and then a clear paint (B) is applied. The method for coating a porcelain tile wall according to claim 3, wherein the clear paint (B) contains a photo-curable resin having a maleimide group as a resin component. The method for coating a porcelain tile wall according to claim 3 or 4, wherein the clear coating (B) contains an organosilicate compound. A method for coating the wall of a porcelain tile, comprising applying a water-repellent treatment agent (A) by the method according to claim 1 or 2, and further applying a coating agent (C) containing titanium oxide having photocatalytic activity. A porcelain tile wall finished by the coating method according to any one of claims 1 to 6.