JP3652864B2

JP3652864B2 - Anticorrosion paint composition

Info

Publication number: JP3652864B2
Application number: JP33862997A
Authority: JP
Inventors: 央加納; 正司浜; 茂男猪俣
Original assignee: Kansai Paint Co Ltd
Current assignee: Kansai Paint Co Ltd
Priority date: 1997-12-09
Filing date: 1997-12-09
Publication date: 2005-05-25
Anticipated expiration: 2017-12-09
Also published as: JPH11172195A

Description

【０００１】
【発明の属する技術分野】
本発明は、低温環境下での硬化性に優れた防食塗料組成物に関し、特にバラストタンクなどの船舶内部の塗装に有用なタ−ルフリ−の防食塗料組成物に関する。
【０００２】
【従来技術及びその課題】
従来、船舶・鋼構造物等の防食塗料としてタ−ルエポキシ塗料が使用されてきている。該塗料は防食性、耐水性、耐薬品性などに優れるものであるが、タ−ルを含有することから安全衛生上の問題が懸念されるだけでなく、黒色であるため維持管理がしにくく密閉場所では暗くなるので作業に危険が伴うなどの不具合があった。そこで、タ−ルの代わりに石油系の樹脂を用いて、特にバラストタンクなどの船舶内部の塗装に有用な淡彩色仕上げが可能な塗料について種々検討されており、本出願人らも特定の性状を有する石油樹脂を含有する防食塗料組成物を提案している（特開平９−２６３７１３号、特開平９−３０２２７６号公報）。これらは、アミン系硬化剤との相溶性に比較的優れる石油樹脂を含み、防食性、耐水性、付着性等に優れた淡彩色塗膜が形成できるが、低温環境下では、使用するアミン系硬化剤によって硬化性が不十分となり、塗膜性能が得られない場合があった。
【０００３】
従来から、エポキシ樹脂及びアミン系硬化剤を含む系では、冬期などの低温環境下での硬化性が悪く、エポキシ樹脂本来の性能が発揮されない不具合があり、通常、低温環境下ではエポキシ／ウレタン硬化系が採用されていた。該系はエポキシ樹脂をエポキシポリオ−ルとし、これにイソシアネ−ト類を硬化剤として用いてなるものであり、低温硬化性に非常に優れている。しかしながら、この硬化系では多湿時にイソシアネ−トが発泡しやすく、また長期の防食性が不十分であり、さらに防食塗料に使用される石油系の樹脂との相溶性が極めて悪く、重防食塗料での設計が困難であるという不具合があった。
【０００４】
【課題を解決するための手段】
本発明者らは、上記問題を解決すべく鋭意検討した結果、特定組成のマンニッヒ反応物をさらにエポキシ変性することにより、特に低温環境下での硬化性に優れ、また石油系樹脂との相溶性にも優れるアミン系硬化剤を用いることにより、低温硬化性に優れたタ−ルフリ−防食塗料が得られ、防食性、耐水性、付着性等に優れた淡彩色塗膜が形成できることを見出し本発明に到達した。
【０００５】
すなわち本発明は、（Ａ）エポキシ樹脂、（Ｂ）アミン系硬化剤、及び（Ｃ）石油系樹脂からなり、該アミン系硬化剤（Ｂ）が、（ａ）キシレンジアミン及び脂肪族ポリアミンの混合物、（ｂ）ビスフェノ−ルＡ、ビスフェノ−ルＦ、石炭酸から選ばれる少なくとも１種及び炭素数９以上のアルキル鎖を有するアルキルフェノ−ルの混合物及び（ｃ）ホルムアルデヒドの縮合反応物に、（ｄ）１分子中に２個以上エポキシ基を含有するエポキシ樹脂を反応させてなるものであり、且つ該石油系樹脂（Ｃ）を硬化樹脂固形分１００重量部に対して２０〜１５０重量部含有することを特徴とする防食塗料組成物を提供するものである。
【０００６】
【発明の実施の形態】
本発明においてエポキシ樹脂（Ａ）は、１分子中に少なくとも２個以上のエポキシ基を有するものであり、エポキシ当量が１５０〜６００、好ましくは１３０〜３００のものが適当である。かかるエポキシ樹脂としては、例えばビスフェノ−ル型エポキシ樹脂、脂肪族エポキシ樹脂、グリシジルエステル系エポキシ樹脂、グリシジルアミン系エポキシ樹脂、フェノ−ルノボラック型エポキシ樹脂、クレゾ−ル型エポキシ樹脂、ダイマ−酸変性エポキシ樹脂など従来公知のものが挙げられ、これらは１種又は２種以上混合して使用してもよい。
【０００７】
本発明においてアミン系硬化剤（Ｂ）は、（ａ）アミン、（ｂ）フェノ−ル及び（ｃ）ホルムアルデヒドの縮合反応物に、（ｄ）１分子中に２個以上エポキシ基を含有するエポキシ樹脂を反応させてなる硬化剤である。
【０００８】
上記アミン（ａ）は、キシレンジアミン及び脂肪族ポリアミンの混合物である。脂肪族ポリアミンとしては、例えばジエチレントリアミン、トリエチレンテトラミンなどが好適に使用できる。
【０００９】
該アミン（ａ）において、キシレンジアミン及び脂肪族ポリアミンの混合比は重量比で２／１〜１／２の範囲が好適である。該混合比からキシレンジアミンが多すぎると、得られる塗膜の付着性が劣り、一方脂肪族ポリアミンが多すぎると低温硬化性が劣り、石油系樹脂との相溶性も低下するので好ましくない。
【００１０】
上記フェノ−ル（ｂ）は、ビスフェノ−ルＡ、ビスフェノ−ルＦ、石炭酸から選ばれる少なくとも１種及び炭素数９以上のアルキル鎖を有するアルキルフェノ−ルの混合物である。アルキルフェノ−ルは、炭素数９以上のアルキル鎖を有する。かかる炭素数９未満では、石油系樹脂との相溶性も低下するので望ましくない。該アルキルフェノ−ルとしては、例えばノニルフェノ−ル、ドデシルフェノ−ル、カルダノ−ルなどが挙げられる。
【００１１】
該フェノ−ル（ｂ）において、ビスフェノ−ルＡ、ビスフェノ−ルＦ、石炭酸から選ばれる少なくとも１種及びアルキルフェノ−ルの混合比は重量比で２／１〜１／２の範囲が好適である。該混合比からビスフェノ−ルＡ、ビスフェノ−ルＦ、石炭酸から選ばれる少なくとも１種が多すぎると石油系樹脂との相溶性が低下し、一方アルキルフェノ−ルが多すぎると低温硬化性、耐水性が低下するので好ましくない。
【００１２】
上記エポキシ樹脂（ｄ）は、１分子中に２個以上エポキシ基を含有するものであり、エポキシ当量が１５０〜６００のものが適当である。該エポキシ樹脂（ｄ）としては、特にビスフェノ−ル型エポキシ樹脂が耐水性、低温硬化性の点から好適である。
【００１３】
上記アミン系硬化剤（Ｂ）の製造は、従来公知の方法に従って行なうことができ、まず上記（ａ）、（ｂ）及び（ｃ）成分を混合し５０〜１８０℃に加熱・脱水して、マンニッヒ反応による縮合反応物を得た後、これに（ｄ）成分を加えて２０〜２００℃に加熱し、該縮合反応物中のアミノ基にエポキシ基を反応させてなる。
【００１４】
上記（ａ）、（ｂ）、（ｃ）及び（ｄ）成分の使用モル比は、（ａ）１モルに対して（ｂ）が０．７〜１．３モル、（ｃ）が０．７〜１．３モル及び（ｄ）が０．２〜０．５モルであることが好適である。該使用モル比の範囲を越えて、（ａ）成分量が多くなると低温硬化性が低下し、また塗膜表面から未反応物がブリ−ドする恐れがあり、一方（ａ）成分量が少ないとやはり硬化性が低下し、未反応の（ｂ）成分が塗膜に残存し耐水性が低下するので好ましくない。
【００１５】
上記（Ａ）及び（Ｂ）成分の混合割合は、両者の使用種により適宜選択されるが、通常［（Ｂ）中の活性水素当量／（Ａ）中のエポキシ当量］の当量比が０．５〜１．０の範囲となるようにするのが適当である。
【００１６】
本発明において石油系樹脂（Ｃ）は、通常、常温で固形状の石油樹脂で、その軟化点が５０〜１５０℃、好ましくは８０〜１００℃であるものが好適に使用でき、該石油樹脂としては、例えば石油ナフサ分解で副生する重質油中からスチレン誘導体、インデン等のＣ₉留分を重合させた芳香族系石油樹脂、前記Ｃ₅留分とＣ₉留分を共重合させた共重合系石油樹脂、シクロペンタジエン、１，３−ペンタジエン等のＣ₅留分の共役ジエンが一部環化重合した脂肪族系石油樹脂、芳香族系石油樹脂を水素添加した樹脂やジシクロペンタジエンを重合させた脂環族系石油樹脂などが挙げられる。
【００１７】
上記石油系樹脂（Ｃ）の軟化点が５０℃未満では、塗膜の耐水性が低下し塗膜表面に該成分がブリ−ドして粘着性が残存する場合あり、一方１５０℃を越えると塗料粘度が高くなり作業性が低下したり、塗膜物性が低下するので望ましくない。
【００１８】
特に、該石油系樹脂（Ｃ）としては、１分子中に０．５〜１．５モルの水酸基を含有し、その軟化点が５０〜１５０℃である水酸基含有石油樹脂が好適に使用できる。該水酸基含有石油樹脂は、上記例示の石油樹脂に水酸基が導入されたものであり、これらのうち特に水酸基含有芳香族系石油樹脂が耐水性、（Ａ）及び（Ｂ）成分との相溶性の点から好適である。
【００１９】
該水酸基含有石油樹脂中の水酸基の含有量が、１分子中に０．５モル未満では上記アミン硬化剤との相溶性が低下し塗膜性能に悪影響を及ぼし、一方１．５モルを越えると耐水性が低下するので望ましくない。
【００２０】
本発明組成物では上記石油系樹脂（Ｃ）を硬化樹脂固形分１００重量部に対して２０〜１５０重量部、好ましくは５０〜１５０重量部含有する。かかる含有量が２０重量部未満では十分な耐水性が得られず、一方１５０重量部を越えると塗膜が脆く良好な物性が得られなくなり、また低温硬化性が著しく低下するので好ましくない。
【００２１】
本発明組成物には、さらに必要に応じて、その他の液状の改質剤や希釈剤；体質顔料、防錆顔料、着色顔料等の顔料類；反応性希釈剤；有機溶剤、沈降防止剤、タレ止め剤、湿潤剤、反応促進剤、付着性付与剤、脱水剤等の通常の塗料用添加剤などを適宜含有してもよい。
【００２２】
また本発明組成物は、エポキシ樹脂（Ａ）及び石油系樹脂（Ｃ）を含む主剤とアミン系硬化剤（Ｂ）からなる二液型塗料であり、通常、ジンクプライマ−などの一次防錆塗膜上に塗装される。上記塗料の塗装方法には、エアスプレ−、エアレススプレ−、刷毛塗り、ロ−ラ−などの従来公知の方法が採用でき、上記塗料を乾燥膜厚で１５０〜５００μｍとなるよう塗布することができる。
【００２３】
【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、「部」及び「％」はそれぞれ「重量部」及び「重量％」を示す。
【００２４】
アミン系硬化剤の製造
製造例１
攪拌機、温度計付き反応容器に、キシレンジアミン６８ｇ（０．５モル）、ジエチレントリアミン５２ｇ（０．５モル）、ビスフェノ−ルＡ１１４ｇ（０．５モル）、及びノニルフェノ−ル１１０ｇ（０．５モル）を仕込み、十分撹拌した後、３７％ホルマリン８１ｇ（１モル）を加えて反応させた。さらに温度を１００℃に上げて２時間反応させた後、脱水して縮合反応物を得た。これに「エポン＃８２８」（エポキシ当量１９０、油化シェルエポキシ社製、エポキシ樹脂）９５ｇ（０．２５モル）を加え、８０℃で２時間反応させた後、トルエン／イソプロパノ−ル＝１／１の混合溶剤で希釈し不揮発分６０％のアミン系硬化剤（Ｂ−１）を得た。該硬化剤液の粘度は、９００ｃｐｓ（２５℃／６０ｒｐｍ、Ｂ型粘度計）であった。
【００２５】
製造例２〜１０
製造例１において、表１に示す組成とする以外は製造例１と同様の操作で各アミン系硬化剤（Ｂ−２）〜（Ｂ−９）を得た。製造例１０は高粘度となり製造不可能であった。尚、表１の組成はモル比で示し、表１中の（注１）、（注２）は、下記の通りである。
【００２６】
（注１）「エポン＃１００１」：エポキシ当量４７５、油化シェルエポキシ社製、エポキシ樹脂
（注２）「エポン＃５２０」：油化シェルエポキシ社製、モノエポキシ化合物
【００２７】
【表１】

【００２８】
防食塗料の作成
実施例１
１リットル容器に、「エポン＃８２８」１００部、チタン白７０部、タルク１００部、水酸基含有石油樹脂（注３）１００部、タレ止め剤（注４）１０部及びキシレン１０部を添加しディスパ−で混合・攪拌し分散して主剤とし、これにアミン硬化剤（Ｂ−１）１００部を塗装直前に添加し混合・攪拌して防食塗料を得た。
【００２９】
（注３）「ネオポリマ−Ｋ−２」：１分子中水酸基含有量１〜１．１モルのジビニルトルエン−インデン共重合物、軟化点１００℃、日本石油化学社製
（注４）「ディスパロンＡ６３０−２０ＸＮ」：ポリアマイド系ワックス、楠本化成社製
実施例２〜６及び比較例１〜９
実施例１において、表２に示す組成及び配合量とする以外は実施例１と同様の操作で各防食塗料を得た。表２中の（注５）、（注６）は、下記の通りである。
（注５）「バ−サミンＦ２０」：マンニッヒ変性メタキシレンジアミン、活性水素当量８０、ヘンケルジャパン社製
（注６）「コロネ−トＬ」：イソシアネ−ト硬化剤、トリレンジイソシアネ−ト変性物、ＮＣＯ含有率１３％、日本ポリウレタン社製
性能試験
上記の通り得られた各防食塗料を下記性能試験に供した。結果を表３に示す。
（＊１）相溶性
各防食塗料において、主剤と硬化剤を混合直後、ガラス板に夫々乾燥膜厚で約２５０μｍとなるようアプリケ−タ−塗装し、５℃で２４時間放置後の塗膜外観を目視で評価した（○：異常なし、△：ニゴリが認められる、×：分離する）。
（＊２）低温硬化性
各防食塗料を、脱脂した磨き軟鋼板（１５０×７０×０．８ｍｍ）にエアレススプレ−にて約２５０μｍ（乾燥膜厚）となるように塗装し、５℃×６５％ＲＨの雰囲気で１６時間乾燥した後の塗膜外観を目視で評価した（○：指で強く押しても膜がずれない、△：指で強く押しても膜がずれる、×：指で軽く押しても膜がずれる）。
【００３０】
（＊３）屈曲性
各防食塗料を、脱脂した磨き軟鋼板（１５０×７０×０．８ｍｍ）にエアレススプレ−にて約２５０μｍ（乾燥膜厚）となるように塗装し、２０℃×６５％ＲＨの雰囲気で７日間乾燥して各試験塗板を作成した。該塗板を２０℃雰囲気で塗面を外側にして９０°に折り曲げ、折り曲げ部分の塗膜の亀裂を目視で評価した（○：亀裂なし、△：わずかに亀裂がある、×：かなり亀裂がある）。
【００３１】
（＊４）温度差耐水性
ショットブラスト鋼板（３００×１００×３．２ｍｍ）（試験板Ｉ）、及び該鋼板上に「ＳＤジンク１０００ＨＡ」（関西ペイント社製、シリケ−トジンクプライマ−）を約２５μｍ（乾燥膜厚）となるように塗装し１日乾燥してなる（試験板II）上に、上記で得た各防食塗料をそれぞれエアレススプレ−にて約２５０μｍ（乾燥膜厚）となるように塗装し、５℃×６５％ＲＨの雰囲気で７日間乾燥して各試験塗板を得た。
【００３２】
該塗板の塗装面が４０℃の温水に、裏面が２０℃の水に接するような浸漬槽中に１４日間浸漬した後、塗面状態を目視で評価した（○：異常なし、△：フクレ、さびの発生が少し認められる、×：フクレさびが著しく発生）。
【００３３】
（＊５）耐海水性
上記（＊４）と同様にして得た各試験塗板を、５０℃の海水に３ケ月間浸漬後の塗面状態を目視で評価した（○：異常なし、△：フクレの発生が少し認められる、×：フクレが著しく発生）。
【００３４】
【発明の効果】
本発明によれば、特定組成のマンニッヒ反応物をさらにエポキシ変性してなる、石油系樹脂との相溶性に優れるアミン系硬化剤を用いることにより、安全衛生上問題なく、特に低温硬化性に優れたタ−ルフリ−の防食塗料組成物が得られる。本発明の防食塗料組成物は、防食性、耐水性、付着性に優れた明色の塗膜を形成でき、船舶・鋼構造物の重防食塗料として非常に有用である。
【００３５】
【表２】

【００３６】
【表３】

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an anticorrosion coating composition excellent in curability under a low temperature environment, and more particularly to a tar-free anticorrosion coating composition useful for painting inside a ship such as a ballast tank.
[0002]
[Prior art and its problems]
Conventionally, tar epoxy paints have been used as anticorrosion paints for ships, steel structures and the like. The paint is excellent in corrosion resistance, water resistance, chemical resistance, etc., but since it contains tar, it is not only concerned about safety and health problems, but it is black and difficult to maintain. Since it was dark in an enclosed space, there were problems such as danger associated with work. Therefore, various investigations have been made on paints that can be used for painting in the interior of ships such as ballast tanks using petroleum-based resin instead of tar, and the present applicants also have specific properties. An anticorrosive coating composition containing a petroleum resin having a water content is proposed (Japanese Patent Laid-Open Nos. 9-263713 and 9-302276). These contain petroleum resins that are relatively excellent in compatibility with amine-based curing agents, and can form light-colored coating films with excellent corrosion resistance, water resistance, adhesion, etc., but in low temperature environments, the amine system used The curability may be insufficient due to the curing agent, and the coating film performance may not be obtained.
[0003]
Conventionally, systems containing epoxy resins and amine curing agents have poor curability in low-temperature environments such as winter, and the original performance of epoxy resins has not been demonstrated. Usually, epoxy / urethane cures in low-temperature environments. The system was adopted. In this system, an epoxy resin is used as an epoxy polyol, and an isocyanate is used as a curing agent. The system is very excellent in low-temperature curability. However, in this cured system, the isocyanate tends to foam when wet, and the long-term anticorrosive property is insufficient, and the compatibility with the petroleum resin used in the anticorrosive coating is extremely poor. There was a problem that it was difficult to design.
[0004]
[Means for Solving the Problems]
As a result of intensive studies to solve the above problems, the inventors of the present invention have further improved the curability under a low temperature environment by further epoxy-modifying a Mannich reaction product having a specific composition, and are compatible with petroleum resins. It was found that a tar-free anticorrosive coating excellent in low-temperature curability can be obtained by using an amine-based curing agent excellent in anti-corrosion property, water resistance, adhesion, etc. The invention has been reached.
[0005]
That is, the present invention comprises (A) an epoxy resin, (B) an amine-based curing agent, and (C) a petroleum-based resin, and the amine-based curing agent (B) is a mixture of (a) xylenediamine and an aliphatic polyamine. (B) a mixture of at least one selected from bisphenol A, bisphenol F, and carboxylic acid and an alkylphenol having an alkyl chain of 9 or more carbon atoms and (c) a condensation reaction product of formaldehyde with (d ) An epoxy resin containing two or more epoxy groups in one molecule is reacted, and the petroleum resin (C) is contained in an amount of 20 to 150 parts by weight with respect to 100 parts by weight of the cured resin solid content. The present invention provides an anticorrosion coating composition characterized by the above.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, the epoxy resin (A) has at least two epoxy groups in one molecule and has an epoxy equivalent of 150 to 600, preferably 130 to 300. Examples of such epoxy resins include bisphenol type epoxy resins, aliphatic epoxy resins, glycidyl ester type epoxy resins, glycidyl amine type epoxy resins, phenol novolac type epoxy resins, cresol type epoxy resins, and dimer acid modified epoxies. A conventionally well-known thing, such as resin, is mentioned, These may be used 1 type or in mixture of 2 or more types.
[0007]
In the present invention, the amine-based curing agent (B) is an (a) amine, (b) phenol, and (c) formaldehyde condensation reaction product, and (d) an epoxy containing two or more epoxy groups in one molecule. It is a curing agent obtained by reacting a resin.
[0008]
The amine (a) is a mixture of xylenediamine and aliphatic polyamine. As the aliphatic polyamine, for example, diethylenetriamine, triethylenetetramine and the like can be preferably used.
[0009]
In the amine (a), the mixing ratio of xylenediamine and aliphatic polyamine is preferably in the range of 2/1 to 1/2 by weight. If the xylene diamine is too much from the mixing ratio, the adhesion of the resulting coating film is inferior. On the other hand, if the aliphatic polyamine is too much, the low temperature curability is inferior and the compatibility with the petroleum resin is also not preferred.
[0010]
The phenol (b) is a mixture of at least one selected from bisphenol A, bisphenol F, and coalic acid and an alkylphenol having an alkyl chain having 9 or more carbon atoms. The alkylphenol has an alkyl chain having 9 or more carbon atoms. If the number of carbon atoms is less than 9, it is not desirable because the compatibility with petroleum-based resins also decreases. Examples of the alkylphenol include nonylphenol, dodecylphenol, cardanol and the like.
[0011]
In the phenol (b), the mixing ratio of at least one selected from bisphenol A, bisphenol F, and coalic acid and the alkylphenol is preferably in the range of 2/1 to 1/2 by weight. is there. From the mixing ratio, if at least one selected from bisphenol A, bisphenol F, and carboxylic acid is too much, the compatibility with the petroleum resin is lowered. On the other hand, if there is too much alkylphenol, low temperature curability and water resistance This is not preferable because the properties are lowered.
[0012]
The epoxy resin (d) contains two or more epoxy groups in one molecule, and those having an epoxy equivalent of 150 to 600 are suitable. As the epoxy resin (d), a bisphenol type epoxy resin is particularly preferable from the viewpoint of water resistance and low-temperature curability.
[0013]
The amine-based curing agent (B) can be produced according to a conventionally known method. First, the components (a), (b) and (c) are mixed, heated and dehydrated to 50 to 180 ° C., After obtaining a condensation reaction product by Mannich reaction, the component (d) is added thereto and heated to 20 to 200 ° C. to react an epoxy group with an amino group in the condensation reaction product.
[0014]
The molar ratios of the components (a), (b), (c) and (d) used are (b) 0.7 to 1.3 mol and (c) 0. It is preferable that 7-1.3 mol and (d) are 0.2-0.5 mol. When the amount of component (a) increases beyond the range of the molar ratio used, the low-temperature curability decreases and unreacted material may bleed from the coating surface, while the amount of component (a) is small. After all, the curability is lowered, the unreacted component (b) remains in the coating film and the water resistance is lowered, which is not preferable.
[0015]
The mixing ratio of the above components (A) and (B) is appropriately selected depending on the type of both used, but the equivalent ratio of [active hydrogen equivalent in (B) / epoxy equivalent in (A)] is usually 0.00. It is appropriate to set it in the range of 5 to 1.0.
[0016]
In the present invention, the petroleum resin (C) is usually a solid petroleum resin at normal temperature, and a softening point of 50 to 150 ° C., preferably 80 to 100 ° C. can be suitably used. is set to, for example by-product styrene derivatives from heavy oil, aromatic petroleum resins and C ₉ fraction obtained by polymerization of indene, obtained by copolymerizing the C ₅ fraction and C ₉ fraction in petroleum naphtha cracking copolymerized petroleum resins, cyclopentadiene, 1,3-conjugated dienes of C ₅ fractions, such as pentadiene part cyclic polymerization aliphatic petroleum resins, resins and aromatic petroleum resins and hydrogenated and dicyclopentadiene And alicyclic petroleum resins obtained by polymerizing
[0017]
When the softening point of the petroleum resin (C) is less than 50 ° C., the water resistance of the coating film is lowered and the component may be bred on the surface of the coating film to remain sticky. This is not desirable because the viscosity of the paint is increased and the workability is lowered and the physical properties of the coating film are lowered.
[0018]
In particular, as the petroleum resin (C), a hydroxyl group-containing petroleum resin containing 0.5 to 1.5 mol of hydroxyl group in one molecule and having a softening point of 50 to 150 ° C. can be preferably used. The hydroxyl group-containing petroleum resin is obtained by introducing a hydroxyl group into the above-exemplified petroleum resin. Of these, the hydroxyl group-containing aromatic petroleum resin is particularly resistant to water and compatible with the components (A) and (B). From the point of view, it is preferable.
[0019]
When the hydroxyl group content in the hydroxyl group-containing petroleum resin is less than 0.5 mol in one molecule, the compatibility with the amine curing agent is lowered and the coating film performance is adversely affected. Undesirably, water resistance is reduced.
[0020]
In the composition of the present invention, the petroleum resin (C) is contained in an amount of 20 to 150 parts by weight, preferably 50 to 150 parts by weight, based on 100 parts by weight of the cured resin solid content. If the content is less than 20 parts by weight, sufficient water resistance cannot be obtained. On the other hand, if it exceeds 150 parts by weight, the coating film is brittle and good physical properties cannot be obtained, and the low-temperature curability is remarkably lowered.
[0021]
In the composition of the present invention, if necessary, other liquid modifiers and diluents; pigments such as extender pigments, rust preventive pigments and colored pigments; reactive diluents; organic solvents, anti-settling agents, Ordinary paint additives such as a sagging inhibitor, a wetting agent, a reaction accelerator, an adhesion-imparting agent, and a dehydrating agent may be appropriately contained.
[0022]
The composition of the present invention is a two-component paint comprising a main component containing an epoxy resin (A) and a petroleum resin (C) and an amine curing agent (B), and usually a primary antirust coating such as a zinc primer. Painted on the membrane. Conventionally known methods such as air spray, airless spray, brush coating, and roller can be adopted as the coating method for the coating, and the coating can be applied to a dry film thickness of 150 to 500 μm. .
[0023]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples. “Parts” and “%” indicate “parts by weight” and “% by weight”, respectively.
[0024]
Production of amine curing agent Production Example 1
In a reaction vessel equipped with a stirrer and a thermometer, 68 g (0.5 mol) of xylenediamine, 52 g (0.5 mol) of diethylenetriamine, 114 g (0.5 mol) of bisphenol A, and 110 g (0.5 mol) of nonylphenol Was added and stirred sufficiently, and then 81 g (1 mol) of 37% formalin was added and reacted. Further, the temperature was raised to 100 ° C. and reacted for 2 hours, followed by dehydration to obtain a condensation reaction product. To this was added 95 g (0.25 mol) of “Epon # 828” (epoxy equivalent 190, manufactured by Yuka Shell Epoxy Co., Ltd.), reacted at 80 ° C. for 2 hours, and then toluene / isopropanol = 1 / 1 to obtain an amine-based curing agent (B-1) having a nonvolatile content of 60%. The viscosity of the curing agent solution was 900 cps (25 ° C./60 rpm, B-type viscometer).
[0025]
Production Examples 2 to 10
In Production Example 1, amine-based curing agents (B-2) to (B-9) were obtained in the same manner as in Production Example 1 except that the compositions shown in Table 1 were used. Production Example 10 had a high viscosity and could not be produced. In addition, the composition of Table 1 is shown by molar ratio, and (Note 1) and (Note 2) in Table 1 are as follows.
[0026]
(Note 1) “Epon # 1001”: Epoxy equivalent 475, manufactured by Yuka Shell Epoxy, epoxy resin (Note 2) “Epon # 520”: Monoepoxy compound, manufactured by Yuka Shell Epoxy Co., Ltd.
[Table 1]

[0028]
Preparation of anticorrosion paint Example 1
Add 1 part of "Epon # 828", 70 parts of titanium white, 100 parts of talc, 100 parts of hydroxyl-containing petroleum resin (Note 3), 10 parts of sagging agent (Note 4) and 10 parts of xylene to a 1 liter container. The mixture was stirred and dispersed at − to obtain a main agent, and 100 parts of an amine curing agent (B-1) was added immediately before coating to the mixture, followed by mixing and stirring to obtain an anticorrosive paint.
[0029]
(Note 3) “Neopolymer-K-2”: divinyltoluene-indene copolymer having a hydroxyl group content of 1 to 1.1 mol in the molecule, softening point 100 ° C., manufactured by Nippon Petrochemical Co., Ltd. (Note 4) “Dispalon A630 −20XN ”: Polyamide wax, Examples 2 to 6 and Comparative Examples 1 to 9 manufactured by Enomoto Kasei Co., Ltd.
In Example 1, each anticorrosion coating material was obtained by the same operation as Example 1 except having set it as the composition and compounding quantity shown in Table 2. (Note 5) and (Note 6) in Table 2 are as follows.
(Note 5) “Basamine F20”: Mannich modified meta-xylene diamine, active hydrogen equivalent 80, manufactured by Henkel Japan Ltd. (Note 6) “Colone L”: isocyanate curing agent, tolylene diisocyanate modified Product, NCO content 13%, made by Nippon Polyurethane
Performance test Each anticorrosion paint obtained as described above was subjected to the following performance test. The results are shown in Table 3.
(* 1) Immediately after mixing the main agent and the curing agent in each compatible anticorrosive paint, an applicator was applied to the glass plate to a dry film thickness of about 250 μm, and the coating film appearance after standing at 5 ° C. for 24 hours. Was visually evaluated (◯: no abnormality, Δ: scratched, x: separated).
(* 2) Each low-temperature curing anticorrosion paint was applied to a degreased polished mild steel sheet (150 x 70 x 0.8 mm) with an airless spray to a thickness of about 250 µm (dry film thickness), and 5 ° C x 65 The appearance of the coating film after being dried for 16 hours in an atmosphere of% RH was visually evaluated (◯: the film did not shift even when pressed strongly with a finger, Δ: the film shifted even when pressed strongly with a finger, X: lightly pressed with a finger. The film is displaced).
[0030]
(* 3) Flexibility Each anticorrosive paint was applied to a degreased polished mild steel plate (150 x 70 x 0.8 mm) with an airless spray to a thickness of about 250 µm (dry film thickness), and 20 ° C x 65%. Each test coating plate was prepared by drying in an RH atmosphere for 7 days. The coated plate was folded at 90 ° with the coated surface facing outside in an atmosphere of 20 ° C., and the cracks in the coating film at the bent portion were visually evaluated (◯: no crack, Δ: slightly cracked, ×: considerably cracked) ).
[0031]
(* 4) Temperature difference water-resistant shot blast steel plate (300 × 100 × 3.2 mm) (test plate I) and “SD zinc 1000HA” (manufactured by Kansai Paint Co., Ltd., silicate zinc primer) on the steel plate Each anticorrosion paint obtained above is about 250 μm (dry film thickness) on an airless spray on (test plate II), which is coated and dried for about 25 μm (dry film thickness) for one day. Each test coating plate was obtained by coating for 7 days in an atmosphere of 5 ° C. × 65% RH.
[0032]
After dipping for 14 days in a dipping bath in which the coated surface of the coated plate was in contact with warm water at 40 ° C. and the back surface in contact with water at 20 ° C., the coated surface state was visually evaluated (◯: no abnormality, Δ: swelling, Rust is slightly observed, x: bulge rust is significantly generated).
[0033]
(* 5) Seawater resistance Each test coated plate obtained in the same manner as in (* 4) above was visually evaluated for the state of the coated surface after immersion in seawater at 50 ° C. for 3 months (◯: no abnormality, Δ: Slight occurrence of bulge is observed, x: bulge is significantly generated).
[0034]
【The invention's effect】
According to the present invention, by using an amine curing agent excellent in compatibility with a petroleum resin, which is obtained by further epoxy-modifying a Mannich reaction product having a specific composition, there is no problem in terms of safety and health, and in particular, excellent low temperature curability. A tar-free anticorrosive coating composition is obtained. The anticorrosion coating composition of the present invention can form a light-colored coating film excellent in anticorrosion, water resistance and adhesion, and is very useful as a heavy anticorrosion coating for ships and steel structures.
[0035]
[Table 2]

[0036]
[Table 3]

Claims

(A) an epoxy resin, (B) an amine-based curing agent, and (C) a petroleum-based resin, wherein the amine-based curing agent (B) is (a) a mixture of xylenediamine and aliphatic polyamine, (b) bisphenol A mixture of alkylphenol having at least one selected from A, bisphenol F, and coalic acid and an alkyl chain having 9 or more carbon atoms and (c) a condensation reaction product of formaldehyde, (d) in one molecule It is formed by reacting an epoxy resin containing two or more epoxy groups, and contains 20 to 150 parts by weight of the petroleum resin (C) with respect to 100 parts by weight of the cured resin solid content. Anticorrosion paint composition.

The anticorrosion coating composition according to claim 1, wherein in the component (a), the mixing ratio of xylenediamine and aliphatic polyamine is 2/1 to 1/2 by weight.

The anticorrosive coating composition according to claim 1 or 2, wherein in the component (b), the mixing ratio of bisphenol A and alkylphenol is 2/1 to 1/2 by weight.

In the amine curing agent (B), the use molar ratio of the components (a), (b), (c) and (d) is such that (b) is 0.7 to 1.3 with respect to 1 mol of (a). The anticorrosive coating composition according to any one of claims 1 to 3, wherein the mole, (c) is 0.7 to 1.3 mole, and (d) is 0.2 to 0.5 mole.

The petroleum resin (C) is a petroleum resin containing 0.5 to 1.5 mol of hydroxyl group in one molecule, and has a softening point of 50 to 150 ° C. The anticorrosion coating composition as described.