JP4294765B2 - Room temperature curable coating composition - Google Patents

Description

【００１１】
具体例としては、例えばジヒドロジシクロペンタジエンモノ（メタ）アクリレ−ト、ジヒドロジシクロペンタジエンエチルモノ（メタ）アクリレ−ト、ジヒドロジシクロペンタジエンモノアリルエ−テルなどのジヒドロジシクロペンタジエン誘導体が挙げられる。
【００１２】
その他のビニル系単量体としては、例えばスチレン、（メタ）アクリル酸メチル、（メタ）アクリル酸エチル、（メタ）アクリル酸ｎ−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）アクリル酸ヘキシル、（メタ）アクリル酸２−エチルヘキシル、（メタ）アクリル酸ｎ−オクチル、（メタ）アクリル酸デシル、（メタ）アクリル酸ラウリル、（メタ）アクリル酸ステアリル、（メタ）アクリル酸シクロヘキシル、（メタ）アクリル酸イソボルニル、（メタ）アクリル酸２−ヒドロキシエチル、（メタ）アクリル酸グリシジルなどが挙げられ、これらは１種または２種以上併用して使用できる。
【００１３】
上記ラジカル重合開始剤としては、例えば、２，２´−アゾビスイソブチロニトリル、２，２´−アゾビス（２，４−ジメチルバレロニトリル）等のアゾ系重合開始剤；ラウリルパーオキサイド、ｔ−ブチルパーオキシ−２−エチルヘキサノエート、ベンゾイルパーオキサイド等の過酸化物系重合開始剤等を挙げられる。
【００１４】
上記の通り得られる分散安定剤（ａ）の存在下で重合されるビニル系単量体としては、（メタ）アクリル酸メチル、（メタ）アクリル酸エチル、（メタ）アクリル酸ｎ−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）アクリル酸ヘキシル、（メタ）アクリル酸２−エチルヘキシル、（メタ）アクリロニトリル、（メタ）アクリル酸２−メトキシエチル、（メタ）アクリル酸２−メトキシブチル、（メタ）アクリルアミド、ビニルピロリドン、（メタ）アクリル酸、マレイン酸、（メタ）アクリル酸２−ヒドロキシエチル、（メタ）アクリル酸２−ヒドロキシプロピル、（メタ）アクリル酸３−ヒドロキシプロピル、（メタ）アクリル酸４−ヒドロキシブチル、（メタ）アクリル酸グリシジル、スチレン、ビニルトルエン、α−メチルスチレン、酢酸ビニルなどが挙げられ、これらは１種または２種以上併用して使用できる。
【００１５】
上記分散重合は、前記有機液体中でラジカル重合開始剤の存在下で行なわれる。該ラジカル重合開始剤は前述と同様のものが使用可能である。
【００１６】
上記の通り得られる重合体分散液（Ａ）は、動的光散乱法による光強度平均粒子径が１５０〜９００ｎｍ、多くは２５０〜４００ｎｍ程度の安定な粒子の分散液である。
【００１７】
本発明において樹脂（Ｂ）は、エポキシ基又はアルコ−ル性水酸基を有する樹脂（ｂ）に炭素数８以上の不飽和脂肪酸（ｃ）を反応させて得られる不飽和脂肪酸変性樹脂である。
【００１８】
上記エポキシ基又はアルコ−ル性水酸基を有する樹脂（ｂ）としては、例えば、（メタ）アクリル酸グリシジル、（メタ）アクリル酸２−ヒドロキシエチル等のエポキシ基またはアルコール性水酸基を有するビニル性不飽和単量体３〜７０重量部、好ましくは１０〜４０重量部と、共重合可能な他のビニル性不飽和単量体、例えば、スチレン、（メタ）アクリル酸メチル、（メタ）アクリル酸エチル、（メタ）アクリル酸ｎ−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）アクリル酸ヘキシル、（メタ）アクリル酸２−エチルヘキシル、（メタ）アクリル酸ｎ−オクチル、（メタ）アクリル酸デシル、（メタ）アクリル酸ラウリル、（メタ）アクリル酸ステアリル、（メタ）アクリル酸シクロヘキシル、（メタ）アクリル酸イソボルニル等の３０〜９７重量部、好ましくは６０〜９０重量部を溶液重合させてなるアクリル樹脂等を挙げることができる。エポキシ基またはアルコール性水酸基を有するビニル性不飽和単量体の共重合量が少なすぎると、不飽和脂肪酸（ｃ）の付加反応において塗膜の酸化硬化に十分な量の脂肪酸（ｃ）を付加させることができず、逆に、エポキシ基またはアルコール性水酸基を有するビニル性不飽和単量体の共重合量が多すぎると、樹脂の溶剤への溶解性が低下し、著しい場合には完全に不溶となることがあるので望ましくない。
【００１９】
上記炭素数８以上の不飽和脂肪酸（ｃ）としては、例えば、魚油脂肪酸、アマニ油脂肪酸、脱水ヒマシ油脂肪酸、トール油脂肪酸、大豆油脂肪酸、綿実油脂肪酸、サフラワー油脂肪酸等の（半）乾性油脂肪酸；オレイン酸、リノール酸、リノレイン酸、エレオステアリン酸、リカン酸、リシノール酸、アラキドン酸等の不飽和脂肪酸のうちの１種あるいは２種以上を挙げることができる。
【００２０】
該不飽和脂肪酸（ｃ）の使用割合は、上記エポキシ基又はアルコ−ル性水酸基を有する樹脂（ｂ）の樹脂固形分に対して１〜６０重量％、好ましくは５〜３０重量％となる範囲が適当である。該使用割合が１重量％未満では、十分な硬化性が得られず、一方６０重量％を越えると耐候性に悪影響を及ぼすので望ましくない。
【００２１】
更に脂肪酸（ｃ）を反応させる工程で、必要に応じて、ヤシ油脂肪酸、水添ヤシ油脂肪酸、パーム油脂肪酸等の不乾性油脂肪酸；カプロン酸、カプリン酸、ラウリン酸、ミリスチン酸、パルミチン酸、ステアリン酸等の飽和脂肪酸を同時に反応させることも可能である。
【００２２】
上記樹脂（ｂ）に脂肪酸（ｃ）を反応させる工程では、必要に応じて、反応触媒を用いることができる。該反応触媒としては、例えば、Ｎ，Ｎ−ジメチルアミノエタノール等の３級アミン；臭化テトラブチルアンモニウム等の４級アンモニウム塩等を挙げることができる。
【００２３】
本発明では上記（Ａ）及び（Ｂ）成分を、両者の合計固形分重量に基づいて、（Ａ）が３０〜９０重量％、好ましくは４０〜７０重量％、及び（Ｂ）が１０〜７０重量％、好ましくは３０〜６０重量％となるように含有せしめる。この範囲を外れて（Ａ）が少ない（（Ｂ）が多い）と、塗膜の耐水性が低下し、一方（Ｂ）が少ない（（Ａ）が多い）と、塗膜の硬化性が不十分となるので好ましくない。
【００２４】
本発明組成物は上記（Ａ）及び（Ｂ）成分を主成分とするものであり、これらにさらに必要に応じて酸化硬化反応触媒、顔料類、有機溶剤、紫外線吸収剤、光安定剤、表面調整剤、顔料分散剤、レオロジ−コントロ−ル剤、塗液皮張り防止剤、防カビ剤、防藻剤、可塑剤、消泡剤などの塗料用添加剤を配合することができる。
【００２５】
上記酸化硬化反応触媒は、反応性二重結合同士の酸化による架橋反応を促進する作用を有するもので、具体例としては、例えば、オクチル酸コバルト、ナフテン酸コバルト、オクチル酸マンガン、ナフテン酸マンガン、オクチル酸ジルコニウム、ナフテン酸ジルコニウム、オクチル酸鉛等の有機金属化合物を挙げることができる。
【００２６】
本発明組成物によって得られた塗膜は、表面光沢等の外観が非常に良好で、耐水性、耐薬品性に優れており、かつ、酸化硬化反応触媒存在下では、塗装後わずか数時間で高い常温硬化性および乾燥性を示す。
【００２７】
【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。「部」及び「％」は、それぞれ「重量部」及び「重量％」を意味する。
【００２８】
実施例１
（１）重合体分散液の製造
フラスコ中にミネラルスピリット（日本石油（株）社製「日石Ａソルベント」）８０部を仕込み、窒素ガスを通気しながら、１１０℃まで撹拌を行ないながら昇温した。次いで、温度を１１０℃に保ちながら
スチレン ２５部
メタクリル酸ｎ−ブチル １２部
メタクリル酸ｉ−ブチル ４３部
アクリル酸２−エチルヘキシル ２０部
２，２´−アゾビスイソブチロニトリル １．５部
の混合物を４時間で滴下した。その後１２０℃に昇温した後２時間熟成し、不揮発分５５％のほぼ無色透明の粘稠なアクリル樹脂溶液を得、これを分散安定剤とした。
【００２９】
フラスコ中に上記で製造した分散安定剤１８５．４部、酢酸イソブチル２５．５部及びミネラルスピリット１０１部を仕込み、窒素ガスを通気しながら、１００℃まで撹拌を行ないながら昇温した。次いで、温度を１００℃に保ちながら
メタクリル酸メチル ２５部
アクリル酸エチル １５部
アクリル酸メチル ４０部
アクリル酸２−ヒドロキシエチル ２０部
２，２´−アゾビスイソブチロニトリル １．５部
の混合物を３時間で滴下した。その後１００℃で３時間熟成し、不揮発分５０％の乳白色の重合体分散液を得た。動的光散乱法による光強度平均粒子径（以下、単に「粒子径」と呼ぶ。）は３７０ｎｍであった。
【００３０】
（２）不飽和脂肪酸変性アクリル樹脂溶液の製造
フラスコ中にミネラルスピリット１００部を仕込み、窒素ガスを通気しながら、１１５℃まで撹拌を行ないながら昇温した。次いで、温度を１１５℃に保ちながら
スチレン ２５部
メタクリル酸ｎ−ブチル １４部
メタクリル酸ｉ−ブチル １６部
アクリル酸２−エチルヘキシル １８部
メタクリル酸グリシジル ２７部
２，２´−アゾビスイソブチロニトリル １部
の混合物を４時間で滴下した。その後１１５℃で２時間熟成した後、１４０℃に昇温してから大豆油脂肪酸４３部及び反応触媒としてＮ，Ｎ−ジメチルアミノエタノール０．４部を加え、脂肪酸の付加反応を行なった。樹脂酸価をＫＯＨ滴定法で追跡し、樹脂酸価が１．０以下になった時点を終点とした。反応終了後、ミネラルスピリット４５部で希釈して不揮発分５０％の褐色透明で粘調な樹脂溶液を得た。
【００３１】
（３）常温硬化性組成物の調整
上記工程（１）で得られた重合体分散液及び工程（２）で得られた不飽和脂肪酸変性アクリル樹脂溶液を、樹脂固形分重量比が８０／２０となるように混合し、これらの合計樹脂固形分に対して硬化触媒としてナフテン酸コバルトを０．３重量％及びナフテン酸鉛を１．０重量％となるように添加した後、均一になるまで攪拌を行なって褐色を帯びた乳白色の常温硬化性組成物を得た。
【００３２】
実施例２
実施例１において、重合体分散液の分散安定剤の製造に使用する単量体混合物として下記の混合物を用いた以外は実施例１と同様にして行ない、乳白色の重合体分散液を得た。その粒子径は３５０ｎｍであった。この重合体分散液を用いる以外は実施例１と同様に行なって褐色を帯びた乳白色の常温硬化性組成物を得た。
【００３３】
ファンクリルＦＡ−５１２ＭＴ（注１） １０部
スチレン ２５部
メタクリル酸ｎ−ブチル １２部
メタクリル酸ｉ−ブチル ３３部
アクリル酸２−エチルヘキシル ２０部
２，２´−アゾビスイソブチロニトリル １部
（注１）「ファンクリルＦＡ−５１２ＭＴ」：日立化成工業社製、下記式で示される酸化硬化型モノマ−
【００３４】
【化３】

【００３５】
実施例３
実施例１において、重合体分散液の分散安定剤の製造に使用する単量体混合物として下記の混合物を用いた以外は実施例１と同様にして行ない、乳白色の重合体分散液を得た。その粒子径は３２０ｎｍであった。この重合体分散液を用いる以外は実施例１と同様に行なって褐色を帯びた乳白色の常温硬化性組成物を得た。
【００３６】
ファンクリルＦＡ−５１２ＭＴ（注１） ４０部
スチレン １５部
メタクリル酸ｎ−ブチル １２部
メタクリル酸ｉ−ブチル ２３部
アクリル酸２−エチルヘキシル ２０部
２，２´−アゾビスイソブチロニトリル １．５部
実施例４
実施例１において、不飽和脂肪酸変性アクリル樹脂溶液の製造に使用する不飽和脂肪酸を大豆油脂肪酸からアマニ油脂肪酸に変更する以外は実施例１と同様にして褐色を帯びた乳白色の常温硬化性組成物を得た。
【００３７】
実施例５
実施例１の常温硬化性組成物の調整において、硬化触媒としてナフテン酸マンガンを０．３重量％及びナフテン酸鉛を１．０重量％となるように添加する以外は実施例１と同様にして褐色を帯びた乳白色の常温硬化性組成物を得た。
【００３８】
比較例１
フラスコ中にミネラルスピリット８０部を仕込み、窒素ガスを通気しながら、１１０℃まで撹拌を行ないながら昇温した。次いで、温度を１１０℃に保ちながら
スチレン ２５部
メタクリル酸ｎ−ブチル １２部
メタクリル酸ｉ−ブチル ４３部
アクリル酸２−エチルヘキシル ２０部
２，２´−アゾビスイソブチロニトリル １．５部
の混合物を４時間で滴下した。その後１２０℃に昇温した後２時間熟成し、不揮発分５５％のほぼ無色透明の粘稠なアクリル樹脂溶液を得た。
【００３９】
このアクリル樹脂溶液と、実施例１の工程（１）で得られた重合体分散液とを、樹脂固形分重量比が２０／８０となるように混合し、均一になるまで攪拌を行なって乳白色の組成物を得た。
【００４０】
比較例２
実施例１の工程（２）で得られた不飽和脂肪酸変性アクリル樹脂溶液に、この樹脂固形分に対して硬化触媒としてナフテン酸コバルトを０．３重量％及びナフテン酸鉛を１．０重量％となるように添加した後、均一になるまで攪拌を行なって褐色透明な常温硬化性組成物を得た。
【００４１】
比較例３
実施例３において製造された乳白色の重合体分散液に、この樹脂固形分に対して硬化触媒としてナフテン酸コバルトを０．３重量％及びナフテン酸鉛を１．０重量％となるように添加した後、均一になるまで攪拌を行なって、やや褐色を帯びた乳白色の常温硬化性組成物を得た。
【００４２】
性能試験
上記実施例及び比較例で得られた各組成物について常温貯蔵１週間における沈降物の有無により貯蔵安定性を評価した（○：沈降物無）。さらに各組成物を３００μｍのアプリケーターで塗装後、常温乾燥させた塗板に対して下記性能試験による評価を行なった。結果を表１に示す。
【００４３】
（＊１）初期乾燥性：ガラス板上に各組成物を３００μｍのアプリケーターで塗装後、２０℃、７５％ＲＨで６時間放置後の指触乾燥性を調べた。
【００４４】
◎：全く指紋がつかない
○：わずかに指紋がつく
△：指紋がつく
×：塗膜が指に付着する
（＊２）２回塗り作業性：ガラス板上に各組成物を３００μｍのアプリケーターで塗装後、２０℃、７５％ＲＨで６時間放置後、もう１度各組成物を刷毛で乾燥膜厚８０〜１００μｍとなるように塗装した後の塗膜の状態を観察した。
【００４５】
○：異常なし
△：塗膜にチヂミが認められる
×：１回目塗装時の塗膜が再溶解し、刷毛さばきが重くなる
（＊３）塗膜光沢：「アレスセラマイルド」（関西ペイント社製、白色の艶消し塗料）を塗装してなるスレ−ト板上に、各組成物を３００μｍのアプリケーターで塗装し１週間乾燥後、６０°鏡面反射率を測定し、８０％以上を○とした。
【００４６】
（＊４）耐水性：スレ−ト板上に各組成物を３００μｍのアプリケーターで塗装し常温乾燥させた塗板を、上水（２０℃）に３日間浸漬した後の塗膜の状態を観察した。
【００４７】
○：異常なし
△：わずかにフクレが認められる
×：著しくフクレが認められる
（＊５）耐酸性：（＊１）と同様にして得た塗板にＯ．１Ｎの硫酸水溶液０．５ｃｃを滴下し、２０℃で２４時間放置後、水洗して塗膜の状態を観察した。
【００４８】
○：異常なし
△：わずかに白化が認められる
×：著しく白化及び表面のエッチングが認められる
（＊６）耐アルカリ性：（＊１）と同様にして得た塗板にＯ．１Ｎの水酸化ナトリウム水溶液０．５ｃｃを滴下し、２０℃で２４時間放置後、水洗して塗膜の状態を観察した。
【００４９】
○：異常なし
△：わずかに白化が認められる
×：著しく白化及び表面のエッチングが認められる
【００５０】
【発明の効果】
本発明によれば、常温硬化型の２種の樹脂成分を特定の使用比で用いることで、初期乾燥性が格段に向上し、貯蔵安定性や２回塗り作業性に優れ、また光沢、耐水性にも優れた塗膜を形成し得る。
【００５１】
【表１】

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a room temperature curable coating composition that is excellent in storage stability and workability for two-time coating, and can form a coating film excellent in initial drying property, glossiness, and water resistance.
[0002]
[Prior art and its problems]
Alkyd resins using unsaturated fatty acids are well known as resins that have room temperature curing after coating and are stable in solution for a long period of time, and are widely used in building interior and exterior paints, Alkyd resins are prone to weathering deterioration due to ultraviolet rays and are insufficient in performance for outdoor use. As a technique for solving this problem of weather resistance, for example, British Patent No. 793,776 proposes an acrylic resin modified with a fatty acid, and Japanese Patent Publication No. 3-71448 as an application example to a non-aqueous dispersion system. The publication proposes a non-water-dispersed acrylic resin and the like obtained by performing dispersion polymerization in the presence of the fatty acid-modified acrylic resin. However, only the fatty acid-modified acrylic resin has insufficient film performance such as water resistance, acid resistance and alkali resistance, and when this is applied to a non-aqueous dispersion system, it has a large particle diameter of 2 during the formation reaction. Secondary particles were produced, a stable dispersion having a narrow particle size distribution was not obtained, and the gloss of the coating film was insufficient.
[0003]
On the other hand, JP-B-52-26260 discloses a non-aqueous dispersion type acrylic resin obtained by performing dispersion polymerization in the presence of an acrylic resin having a vinyl monomer having an oxidatively curable unsaturated group as a copolymerization component. Proposed. According to this, a stable dispersion can be obtained, and a coating film excellent in water resistance, acid resistance and alkali resistance can be formed, but there is a problem that curability at the initial stage of coating film formation is insufficient. .
[0004]
[Means for Solving the Problems]
As a result of intensive studies to solve the above-mentioned problems, the present inventors use two room temperature curing resin components at a specific usage ratio, so that the initial drying property is remarkably improved, storage stability and 2 The present inventors have found that a coating film excellent in spin coating workability, gloss and water resistance can be formed, and has reached the present invention.
[0005]
That is, the present invention relates to (A) an organic liquid in which a vinyl monomer is dissolved and a polymer formed from the monomer does not dissolve, and is soluble in the organic liquid and is oxidatively polymerizable double bond A polymer dispersion obtained by polymerizing the vinyl-based monomer in the presence of a dispersion stabilizer (a) which is a resin having a resin , and (B) (b) a resin having an epoxy group or an alcoholic hydroxyl group (C) a resin obtained by reacting an unsaturated fatty acid having 8 or more carbon atoms, (A) is 30 to 90% by weight based on the total solid weight of (A) and (B), and (B) Is provided so that it may become 10 to 70 weight%, It provides the normal temperature curable coating composition characterized by the above-mentioned.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, the polymer dispersion (A) is a dispersion stabilizer (S) that is soluble in an organic liquid in an organic liquid that dissolves a vinyl monomer and does not dissolve a polymer formed from the monomer. It is obtained by polymerizing the vinyl monomer in the presence of a).
[0007]
Examples of the organic liquid include aliphatic hydrocarbon solvents such as n-hexane, n-octane, 2,2,2-trimethylpentane, isooctane, n-nonane, cyclohexane, and methylcyclohexane; benzene, toluene, xylene, and ethylbenzene. Aromatic hydrocarbon solvents such as mineral spirits, “Swazole 1000” (product of Maruzen Petrochemical Co., Ltd.), petroleum ethers such as petroleum ether, petroleum benzine and petroleum naphtha; ketone solvents such as methyl isobutyl ketone; An ester solvent such as isobutyl; an alcohol solvent such as isopropanol, or the like can be used alone or in admixture of two or more as required.
[0008]
Various conventionally known resins can be applied to the dispersion stabilizer (a) soluble in the organic liquid, and usually a resin having a number average molecular weight of about 1,000 to 100,000. In particular, as the dispersion stabilizer (a), a resin having an oxidatively polymerizable double bond is preferable from the viewpoint of curability of the formed coating film. The resin having an oxidatively polymerizable double bond is usually 5 to 70% by weight, preferably 15 to 50% by weight of a vinyl monomer having an oxidatively polymerizable double bond, and other vinyl monomers 30. It is a resin obtained by radical copolymerization of ˜95% by weight, preferably 50 to 85% by weight in the organic liquid in the presence of a radical polymerization initiator. If the amount of copolymerization of the vinyl monomer having an oxidatively polymerizable double bond is too small, sufficient curability may not be obtained particularly at the initial stage of coating film formation, while the amount of copolymerization is too large. And unreacted monomer may remain, which is not desirable.
[0009]
The vinyl monomer having an oxidatively polymerizable double bond is preferably one having a site represented by the following structural formula in the molecule.
[0010]
[Chemical formula 2]

[0011]
Specific examples include dihydrodicyclopentadiene derivatives such as dihydrodicyclopentadiene mono (meth) acrylate, dihydrodicyclopentadiene ethyl mono (meth) acrylate, dihydrodicyclopentadiene monoallyl ether and the like. .
[0012]
Examples of other vinyl monomers include styrene, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, and t- (meth) acrylic acid. Butyl, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, decyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, (meth ) Cyclohexyl acrylate, isobornyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, glycidyl (meth) acrylate, and the like. These may be used alone or in combination of two or more.
[0013]
Examples of the radical polymerization initiator include azo polymerization initiators such as 2,2′-azobisisobutyronitrile and 2,2′-azobis (2,4-dimethylvaleronitrile); lauryl peroxide, t -Peroxide polymerization initiators such as butylperoxy-2-ethylhexanoate and benzoyl peroxide.
[0014]
Examples of the vinyl monomer polymerized in the presence of the dispersion stabilizer (a) obtained as described above include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, ( (Meth) acrylic acid isobutyl, (meth) acrylic acid t-butyl, (meth) acrylic acid hexyl, (meth) acrylic acid 2-ethylhexyl, (meth) acrylonitrile, (meth) acrylic acid 2-methoxyethyl, (meth) acrylic 2-methoxybutyl acid, (meth) acrylamide, vinylpyrrolidone, (meth) acrylic acid, maleic acid, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, (meth) acrylic acid 3- Hydroxypropyl, 4-hydroxybutyl (meth) acrylate, glycidyl (meth) acrylate, styrene, Nirutoruen, alpha-methyl styrene, vinyl acetate and the like, which can be used in combination one or more.
[0015]
The dispersion polymerization is performed in the organic liquid in the presence of a radical polymerization initiator. As the radical polymerization initiator, the same ones as described above can be used.
[0016]
The polymer dispersion (A) obtained as described above is a dispersion of stable particles having a light intensity average particle diameter of 150 to 900 nm, most of which is about 250 to 400 nm by a dynamic light scattering method.
[0017]
In the present invention, the resin (B) is an unsaturated fatty acid-modified resin obtained by reacting an unsaturated fatty acid (c) having 8 or more carbon atoms with a resin (b) having an epoxy group or an alcoholic hydroxyl group.
[0018]
Examples of the resin (b) having an epoxy group or an alcoholic hydroxyl group include vinyl unsaturated groups having an epoxy group or an alcoholic hydroxyl group such as glycidyl (meth) acrylate and 2-hydroxyethyl (meth) acrylate. 3 to 70 parts by weight of monomer, preferably 10 to 40 parts by weight, and other vinyl unsaturated monomers copolymerizable, such as styrene, methyl (meth) acrylate, ethyl (meth) acrylate, N-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, Decyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, Meth) 30 to 97 parts by weight of acrylic acid isobornyl, preferably an acrylic resin or the like to be by solution polymerizing 60 to 90 parts by weight. If the copolymerization amount of the vinyl unsaturated monomer having an epoxy group or an alcoholic hydroxyl group is too small, an amount of fatty acid (c) sufficient for oxidative curing of the coating film is added in the addition reaction of the unsaturated fatty acid (c). Conversely, if the amount of copolymerization of the vinyl unsaturated monomer having an epoxy group or alcoholic hydroxyl group is too large, the solubility of the resin in the solvent is lowered, This is undesirable because it may become insoluble.
[0019]
Examples of the unsaturated fatty acid (c) having 8 or more carbon atoms include (semi) dryness such as fish oil fatty acid, linseed oil fatty acid, dehydrated castor oil fatty acid, tall oil fatty acid, soybean oil fatty acid, cottonseed oil fatty acid and safflower oil fatty acid. Examples include oil fatty acids; one or more of unsaturated fatty acids such as oleic acid, linoleic acid, linolenic acid, eleostearic acid, ricanoic acid, ricinoleic acid, and arachidonic acid.
[0020]
The proportion of the unsaturated fatty acid (c) used is in the range of 1 to 60% by weight, preferably 5 to 30% by weight, based on the resin solid content of the resin (b) having an epoxy group or an alcoholic hydroxyl group. Is appropriate. If the use ratio is less than 1% by weight, sufficient curability cannot be obtained, while if it exceeds 60% by weight, the weather resistance is adversely affected.
[0021]
Further, in the step of reacting the fatty acid (c), if necessary, non-drying oil fatty acids such as coconut oil fatty acid, hydrogenated coconut oil fatty acid and palm oil fatty acid; caproic acid, capric acid, lauric acid, myristic acid, palmitic acid It is also possible to react a saturated fatty acid such as stearic acid at the same time.
[0022]
In the step of reacting the resin (b) with the fatty acid (c), a reaction catalyst can be used as necessary. Examples of the reaction catalyst include tertiary amines such as N, N-dimethylaminoethanol; quaternary ammonium salts such as tetrabutylammonium bromide.
[0023]
In the present invention, the components (A) and (B) are based on the total solid content weight of both, and (A) is 30 to 90% by weight, preferably 40 to 70% by weight, and (B) is 10 to 70%. It is contained so that it may become weight%, Preferably it is 30 to 60 weight%. Outside this range, when (A) is small (many (B)), the water resistance of the coating film is lowered, while when (B) is small (many (A)), the curability of the coating film is poor. This is not preferable because it is sufficient.
[0024]
The composition of the present invention comprises the above components (A) and (B) as the main components. If necessary, an oxidation curing reaction catalyst, pigments, an organic solvent, an ultraviolet absorber, a light stabilizer, a surface. Additives for paints such as a regulator, a pigment dispersant, a rheology control agent, a coating liquid anti-skinning agent, an antifungal agent, an antialgae agent, a plasticizer, and an antifoaming agent can be blended.
[0025]
The oxidative curing reaction catalyst has an action of promoting a crosslinking reaction by oxidation of reactive double bonds, and specific examples thereof include, for example, cobalt octylate, cobalt naphthenate, manganese octylate, manganese naphthenate, Mention may be made of organometallic compounds such as zirconium octylate, zirconium naphthenate and lead octylate.
[0026]
The coating film obtained by the composition of the present invention has a very good appearance such as surface gloss, excellent water resistance and chemical resistance, and in the presence of an oxidation curing reaction catalyst, only a few hours after coating. High room temperature curing and drying properties.
[0027]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples. “Parts” and “%” mean “parts by weight” and “% by weight”, respectively.
[0028]
Example 1
(1) Production of polymer dispersion Into a flask, 80 parts of mineral spirit (“Nisseki A Solvent” manufactured by Nippon Oil Co., Ltd.) was charged, and the temperature was increased while stirring up to 110 ° C. while ventilating nitrogen gas. did. Next, a mixture of styrene 25 parts n-butyl methacrylate 12 parts i-butyl methacrylate 43 parts 2-ethylhexyl acrylate 20 parts 2,2′-azobisisobutyronitrile 1.5 parts while maintaining the temperature at 110 ° C. Was added dropwise over 4 hours. Thereafter, the temperature was raised to 120 ° C., followed by aging for 2 hours to obtain an almost colorless and transparent viscous acrylic resin solution having a nonvolatile content of 55%, which was used as a dispersion stabilizer.
[0029]
The flask was charged with 185.4 parts of the dispersion stabilizer prepared above, 25.5 parts of isobutyl acetate, and 101 parts of mineral spirit, and the temperature was raised while stirring to 100 ° C. while ventilating nitrogen gas. Next, while maintaining the temperature at 100 ° C., a mixture of methyl methacrylate 25 parts ethyl acrylate 15 parts methyl acrylate 40 parts 2-hydroxyethyl acrylate 20 parts 2,2′-azobisisobutyronitrile 1.5 parts It was dripped in 3 hours. Thereafter, the mixture was aged at 100 ° C. for 3 hours to obtain a milky white polymer dispersion having a nonvolatile content of 50%. The light intensity average particle diameter (hereinafter simply referred to as “particle diameter”) by dynamic light scattering was 370 nm.
[0030]
(2) Production of unsaturated fatty acid-modified acrylic resin solution 100 parts of mineral spirit was charged into a flask, and the temperature was increased while stirring to 115 ° C. while ventilating nitrogen gas. Next, while maintaining the temperature at 115 ° C., styrene 25 parts n-butyl methacrylate 14 parts i-butyl methacrylate 16 parts 2-ethylhexyl acrylate 18 parts glycidyl methacrylate 27 parts 2,2′-azobisisobutyronitrile 1 Part of the mixture was added dropwise over 4 hours. After aging at 115 ° C. for 2 hours, the temperature was raised to 140 ° C., and 43 parts of soybean oil fatty acid and 0.4 part of N, N-dimethylaminoethanol were added as a reaction catalyst to carry out an addition reaction of fatty acid. The resin acid value was traced by the KOH titration method, and the time when the resin acid value became 1.0 or less was taken as the end point. After completion of the reaction, it was diluted with 45 parts of mineral spirits to obtain a brown transparent and viscous resin solution having a nonvolatile content of 50%.
[0031]
(3) Preparation of room temperature curable composition The polymer dispersion obtained in the step (1) and the unsaturated fatty acid-modified acrylic resin solution obtained in the step (2) are mixed at a resin solid content weight ratio of 80/20. And mixed to 0.3% by weight of cobalt naphthenate and 1.0% by weight of lead naphthenate as a curing catalyst with respect to the total resin solid content until uniform. Stirring was performed to obtain a brownish milky white room temperature curable composition.
[0032]
Example 2
In Example 1, it carried out like Example 1 except having used the following mixture as a monomer mixture used for manufacture of the dispersion stabilizer of a polymer dispersion, and the milky white polymer dispersion was obtained. Its particle size was 350 nm. A brownish milky white room temperature curable composition was obtained in the same manner as in Example 1 except that this polymer dispersion was used.
[0033]
Fancryl FA-512MT (Note 1) 10 parts Styrene 25 parts n-butyl methacrylate 12 parts i-butyl methacrylate 33 parts 2-ethylhexyl acrylate 20 parts 2,2'-azobisisobutyronitrile 1 part (Note) 1) “Fancryl FA-512MT”: manufactured by Hitachi Chemical Co., Ltd., an oxidation hardening type monomer represented by the following formula
[0034]
[Chemical 3]

[0035]
Example 3
In Example 1, it carried out like Example 1 except having used the following mixture as a monomer mixture used for manufacture of the dispersion stabilizer of a polymer dispersion, and the milky white polymer dispersion was obtained. The particle size was 320 nm. A brownish milky white room temperature curable composition was obtained in the same manner as in Example 1 except that this polymer dispersion was used.
[0036]
Fanacrylyl FA-512MT (Note 1) 40 parts Styrene 15 parts n-butyl methacrylate 12 parts i-butyl methacrylate 23 parts 2-ethylhexyl acrylate 20 parts 2,2'-azobisisobutyronitrile 1.5 parts
Example 4
In Example 1, except that the unsaturated fatty acid used for the production of the unsaturated fatty acid-modified acrylic resin solution is changed from soybean oil fatty acid to linseed oil fatty acid, a brownish milky white room temperature curable composition in the same manner as in Example 1 I got a thing.
[0037]
Example 5
In the preparation of the room temperature curable composition of Example 1, the same procedure as in Example 1 was conducted except that manganese naphthenate was added as a curing catalyst in an amount of 0.3% by weight and lead naphthenate at 1.0% by weight. A brownish milky white room temperature curable composition was obtained.
[0038]
Comparative Example 1
The flask was charged with 80 parts of mineral spirit and heated to 110 ° C. while stirring with nitrogen gas. Next, a mixture of styrene 25 parts n-butyl methacrylate 12 parts i-butyl methacrylate 43 parts 2-ethylhexyl acrylate 20 parts 2,2′-azobisisobutyronitrile 1.5 parts while maintaining the temperature at 110 ° C. Was added dropwise over 4 hours. Thereafter, the temperature was raised to 120 ° C., followed by aging for 2 hours to obtain a substantially colorless and transparent viscous acrylic resin solution having a nonvolatile content of 55%.
[0039]
This acrylic resin solution and the polymer dispersion obtained in the step (1) of Example 1 were mixed so that the resin solid content weight ratio was 20/80, and stirred until it became uniform. A composition was obtained.
[0040]
Comparative Example 2
In the unsaturated fatty acid-modified acrylic resin solution obtained in the step (2) of Example 1, 0.3% by weight of cobalt naphthenate and 1.0% by weight of lead naphthenate are used as a curing catalyst with respect to the resin solid content. Then, the mixture was stirred until it became uniform to obtain a brown transparent room temperature curable composition.
[0041]
Comparative Example 3
To the milky white polymer dispersion prepared in Example 3, 0.3 wt% cobalt naphthenate and 1.0 wt% lead naphthenate were added as a curing catalyst to the resin solid content. Thereafter, the mixture was stirred until it became uniform to obtain a slightly brownish milky white room temperature curable composition.
[0042]
Performance test The storage stability of each of the compositions obtained in the above Examples and Comparative Examples was evaluated based on the presence or absence of precipitates at room temperature storage for 1 week (O: no precipitate). Furthermore, after coating each composition with a 300 μm applicator, the coated plate dried at room temperature was evaluated by the following performance test. The results are shown in Table 1.
[0043]
(* 1) Initial drying property: Each composition was coated on a glass plate with a 300 μm applicator, and the touch drying property after leaving at 20 ° C. and 75% RH for 6 hours was examined.
[0044]
◎: No fingerprint at all ○: Slight fingerprint is attached △: Fingerprint is attached ×: The coating film adheres to the finger (* 2) Double coating workability: Each composition is applied on a glass plate with a 300 μm applicator After coating, the film was allowed to stand at 20 ° C. and 75% RH for 6 hours, and then the state of the coating film after the coating of each composition with a brush to a dry film thickness of 80 to 100 μm was observed.
[0045]
○: No abnormality △: Chijimi is observed in the coating film ×: The coating film is redissolved at the first coating and the brush handling becomes heavy (* 3) Gloss of coating film: “Ares Ceramild” (manufactured by Kansai Paint Co., Ltd.) Each composition was coated with a 300 μm applicator on a slate plate coated with a white matte paint), dried for 1 week, measured for 60 ° specular reflectance, and 80% or more was rated as ◯. .
[0046]
(* 4) Water resistance: The state of the coating film after observing the coated plate obtained by coating each composition on a plate with a 300 μm applicator and drying at room temperature for 3 days in clean water (20 ° C.) was observed. .
[0047]
◯: No abnormality Δ: Slight bulge is observed ×: Severe bulge is observed (* 5) Acid resistance: O.D. on the coated plate obtained in the same manner as (* 1). A 1 N aqueous sulfuric acid solution (0.5 cc) was added dropwise, left at 20 ° C. for 24 hours, washed with water, and the state of the coating film was observed.
[0048]
◯: No abnormality Δ: Slight whitening is observed X: Remarkable whitening and surface etching are observed (* 6) Alkali resistance: O.D. on the coated plate obtained in the same manner as (* 1) A 1N sodium hydroxide aqueous solution (0.5 cc) was added dropwise, left at 20 ° C. for 24 hours, washed with water, and the state of the coating film was observed.
[0049]
○: No abnormality △: Slight whitening is observed ×: Remarkably whitening and surface etching are observed [0050]
【The invention's effect】
According to the present invention, by using two kinds of room temperature curing resin components in a specific use ratio, initial drying property is remarkably improved, storage stability and two-time coating workability are excellent, and gloss and water resistance are improved. It is possible to form a coating film having excellent properties.
[0051]
[Table 1]

Claims (4)

(A) Dispersion which is a resin soluble in an organic liquid and having an oxidative polymerizable double bond in an organic liquid in which a vinyl monomer is dissolved and a polymer formed from the monomer is not dissolved A polymer dispersion obtained by polymerizing the vinyl monomer in the presence of the stabilizer (a), and (B) (b) a resin having an epoxy group or an alcoholic hydroxyl group (c) A resin obtained by reacting 8 or more unsaturated fatty acids, (A) is 30 to 90% by weight, and (B) is 10 to 70% by weight based on the total solid weight of (A) and (B). A room-temperature curable coating composition characterized by comprising: A resin having an oxidatively polymerizable double bond is obtained by copolymerizing 5 to 70% by weight of a vinyl monomer having an oxidatively polymerizable double bond with 30 to 95% by weight of another vinyl monomer. cold-curing coating composition according to claim 1, wherein the resin. The room temperature curable coating composition according to claim 2, wherein the vinyl monomer having an oxidatively polymerizable double bond has a moiety represented by the following structural formula in the molecule.

Resin (b) is an epoxy group or alkoxyalkyl - vinyl monomer and any one of claims 1 to 3 and other vinyl monomer is a resin obtained by copolymerizing with Le hydroxyl cold-curing coating composition according to.