JPWO2005019358A1 - Coating composition for forming a heat-shielding film and coating method using the same - Google Patents

Abstract

The present invention includes (A) a resin component that forms a film having a refractive index in the range of 1.30 to 1.60, and (B) an average primary particle diameter in the range of 500 to 2,000 nm and a refractive index. The present invention provides a coating composition for forming a heat-shielding film containing a white pigment in the range of 1.80 to 3.00, and a coating method using the coating composition.

Description

  The present invention relates to a coating composition capable of forming a heat-shielding film that suppresses an increase in internal temperature of a building or the like, and a coating method using the same.

It is necessary to suppress the rise in the internal temperature of the building due to the irradiation of sunlight, etc., in order to reduce air conditioning costs. In particular, inorganic building materials such as concrete used as building materials for buildings, houses and the like have high heat storage properties, and promote the temperature rise inside the building.
On the other hand, in oil tanks, grain tanks, etc., the temperature difference between the inside and outside of the tank increases due to the irradiation of sunlight, which causes problems such as evaporation of volatile components and deterioration of grains.
Accordingly, there is a demand for the development of a coating composition for forming a heat-shielding film that can give a sufficient heat-shielding effect to the outer wall and roof of a building, the outer surface of a tank, and the like.
Conventionally, it is known that a white coating film formed from a coating composition containing a titanium dioxide pigment having an average particle size of about 200 to 300 nm is excellent in base concealing properties and exhibits a certain degree of heat shielding effect. However, the heat shielding effect was not satisfactory. Further, when the coating composition is further mixed with a color pigment to color the coating film in a deep color, the heat shielding effect is significantly reduced.
Japanese Patent Application Laid-Open No. 2-185572 discloses a solar heat shielding coating composition containing a resin component having excellent weather resistance, a solar heat shielding pigment such as zirconium oxide, and a complex oxide color pigment. According to the composition, a coating film having heat shielding properties and excellent weather resistance can be formed. However, in the case of a dark-colored coating film, the heat shielding effect may not be observed.
Japanese Patent Application Laid-Open No. 11-323197 discloses a thermal barrier coating material containing a ceramic hollow particle (ceramic bubble) and a structure holding agent for densely laminating ceramic bubbles. According to this paint, a coating film having a single layer and a high heat shielding effect can be obtained. However, since the particle diameter of the ceramic bubbles is as large as 5 to 150 μm, there is a problem that the gloss of the coating film is lowered.

An object of the present invention is to provide a coating composition for forming a heat-shielding film that has an excellent heat-shielding effect and can form a coating film having sufficient base concealing property and gloss, and a coating method using the same.
Other objects and features of the present invention will become apparent from the following description.
The inventor has intensively studied to achieve the above object. As a result, the white pigment having an average primary particle diameter in the range of 500 to 2,000 nm and a refractive index in the range of 1.80 to 3.00 reflects and scatters infrared rays as heat rays. According to the coating composition in which this white pigment is blended with a resin component that forms a film having a refractive index of 1.30 to 1.60, it has an excellent heat shielding effect and has a sufficient base concealing property and gloss. It has been found that a coating film can be formed. The present invention has been completed based on such findings.
The present invention provides the following coating composition for forming a heat-shielding film and a coating method using the same.
1. (A) a resin component that forms a film having a refractive index of 1.30 to 1.60, and (B) an average primary particle diameter in the range of 500 to 2,000 nm and a refractive index of 1.80. A coating composition for forming a heat-shielding film containing a white pigment in the range of ˜3.00.
2. Item 2. The coating composition according to Item 1, wherein the resin component (A) contains a crosslinked acrylic resin or a non-crosslinked acrylic resin.
3. Item 2. The coating composition according to Item 1, wherein the resin component (A) contains a carbonyl group-containing acrylic copolymer and a hydrazine derivative.
4). Item 2. The coating composition according to Item 1, wherein the resin component (A) contains a maleimide group-containing acrylic copolymer.
5). Item 2. The coating composition according to Item 1, wherein the resin component (A) contains an unsaturated fatty acid-modified acrylic resin.
6). Item 2. The coating composition according to Item 1, wherein the white pigment (B) is titanium dioxide and / or zinc oxide.
7). Item 2. The coating composition according to Item 1, wherein the white pigment (B) is blended in an amount of 10 to 140 parts by weight per 100 parts by weight of the resin component (A).
8). Furthermore, the coating composition of said claim | item 1 containing the white pigment (C) whose average primary particle diameter is less than 400 nm.
9. Item 9. The coating composition according to Item 8, wherein the white pigment (C) is titanium dioxide and / or zinc oxide.
10. Item 10. The coating composition according to Item 8, wherein the white pigment (C) is blended in an amount of 10 to 140 parts by weight per 100 parts by weight of the resin component (A).
11. Item 9. The coating composition according to Item 8, wherein the weight ratio of the white pigment (B) and the white pigment (C) is in the range of 10/90 to 90/10.
12 Furthermore, the coating composition of the said claim | item 1 containing a coloring pigment (D).
13. Item 13. The coating composition according to Item 12, containing a plurality of chromatic pigments having a complementary color relationship as the color pigment (D).
14 Item 5. A top coating composition which is a coating composition for forming a heat-shielding film according to Item 1.
15. Item 15. The above item 14 further contains a colored paint (D) and can form a coating film having a lightness (L ^* value) of 20 to 70 based on the L ^* a ^* b ^* color system defined in JIS Z 8729. Topcoat paint composition.
16. An undercoat paint composition, which is the paint composition for forming a heat-shielding film according to Item 1.
17. Item 17. The undercoat coating composition according to Item 16, which can form a coating film having a lightness (L ^* value) of 70 to 98 based on the L ^* a ^* b ^* color system defined in JIS Z 8729.
18. The coating method which coat | covers the top coat composition of said claim | item 14 with a single layer on to-be-coated material.
19. Item 15. A coating method in which an undercoating composition is applied to an article, and then the topcoating composition according to Item 14 is coated on the coated surface.
20. The coating method which coats the top-coat coating composition on this coating surface after applying the undercoat coating composition of said claim | item 16 to a to-be-coated article.
21. Item 21. The coating method according to Item 20, wherein the top coating composition is a coating composition containing a perylene pigment.

The invention's effect

各式中、Ｒ^１及びＲ^２は、独立して、水素原子又はメチル基を示す。Ｒ^３及びＲ^４は、独立して、炭素数４以下のアルキル基を示す。ｎは１〜６の整数を示す。
その他のエチレン性不飽和単量体としては、前記カルボニル基含有アクリル共重合体エマルションの製造に用いるその他のエチレン性不飽和単量体として列記したものと同様のものを使用することができる。
樹脂成分（Ａ）として、カルボニル基含有アクリル共重合体エマルション及びマレイミド基含有アクリル共重合体エマルションを併用することもできる。この場合の併用割合は、前者／後者の固形分重量比で３／９７〜９７／３程度、好ましくは１０／９０〜９０／１０程度の範囲である。また、この併用の場合、カルボニル基含有アクリル樹脂に対して、前記ヒドラジン誘導体を組み合わせて使用することもできる。
樹脂成分（Ａ）として、有機溶剤可溶型である不飽和脂肪酸変性アクリル樹脂を、好ましく使用できる。不飽和脂肪酸変性アクリル樹脂は、常温で酸化重合することにより、自己架橋する。また、該樹脂中の不飽和脂肪酸成分により、白色顔料（Ｂ）配合により発生することがある塗膜光沢の低下を有効に抑制できる。
上記不飽和脂肪酸変性アクリル樹脂は、例えば、有機溶剤の存在下でエポキシ基含有エチレン性不飽和単量体およびその他のエチレン性不飽和単量体を共重合させてエポキシ基含有アクリル共重合体を調製し、そのエポキシ基に不飽和脂肪酸を付加反応させることにより得ることができる。
エポキシ基含有エチレン性不飽和単量体は、１分子中に、少なくとも１個のエポキシ基と重合可能な二重結合とを有する単量体である。該単量体としては、例えば、グリシジル（メタ）アクリレート、β−メチルグリシジル（メタ）アクリレート、３，４−エポキシシクロヘキシルメチル（メタ）アクリレート、３，４−エポキシシクロヘキシルエチル（メタ）アクリレート、３，４−エポキシシクロヘキシルプロピル（メタ）アクリレート、アリルグリシジルエーテル等が挙げられる。
その他のエチレン性不飽和単量体としては、前記カルボニル基含有アクリル共重合体エマルションの製造に用いるその他のエチレン性不飽和単量体として列記したものと同様のものを使用することができる。
不飽和脂肪酸は、形成塗膜を酸化硬化せしめるために導入されるものである。該脂肪酸としては、例えば、魚油脂肪酸、脱水ヒマシ油脂肪酸、サフラワー油脂肪酸、アマニ油脂肪酸、ダイズ油脂肪酸、ゴマ油脂肪酸、ケシ油脂肪酸、エノ油脂肪酸、麻実油脂肪酸、ブドウ核油脂肪酸、トウモロコシ油脂肪酸、トール油脂肪酸、ヒマワリ油脂肪酸、綿実油脂肪酸、クルミ油脂肪酸、ゴム種油脂肪酸等が挙げられる。
また、上記脂肪酸変性アクリル樹脂は、耐候性を向上させる等の目的でシリコン樹脂等で改質してもよい。
また、樹脂成分（Ａ）としては、フッ素樹脂、アクリル樹脂、ポリエステル樹脂、アルキド樹脂、ウレタン樹脂、エポキシ樹脂などの樹脂に水酸基を含有させた樹脂を主剤として、これにポリイソシアネートなどの架橋剤を使用直前に混合する２液型の樹脂組成物も使用できる。例えば、水酸基含有アクリル樹脂を含有するベース樹脂（主剤）に、ポリイソシアネート硬化剤を併用するウレタン硬化型２液型塗料を、好ましく使用できる。
樹脂成分（Ａ）は、必要に応じて、耐汚染化剤としてのオルガノシリケート化合物を含有することができる。該化合物により、形成塗膜が、親水性になり、雨水等により表面が洗浄され易くなるため、汚れにくくなるという利点が得られる。
上記オルガノシリケート化合物としては、例えば、下記式（３）で表される直鎖状の縮合物をあげることができる。

式中、Ｒ^５は、独立して、水素原子又は炭素数１〜１０の炭化水素基を示す。ｍは１〜１００の整数を示す。
炭素数１〜１０の炭化水素基としては、例えば、メチル基、エチル基、ｎ−プロピル基、ｉ−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、ｉ−ペンチル基、ｎ−ヘキシル基、ｉ−ヘキシル基、ｎ−オクチル基などのアルキル基；フェニル基などのアリール基等が好ましい。
上記式（３）のオルガノシリケート化合物としては、Ｒ^５が炭素数１〜４の低級アルキル基であってｍが２〜１５のものが、より好ましい。
上記オルガノシリケート化合物としては、上記式（３）で表される直鎖状の化合物以外に、分岐状の化合物又は環状の化合物も包含される。
また、樹脂成分（Ｂ）が水性である場合においては、上記オルガノシリケート化合物に、ポリエチレングリコール、ポリプロピレングリコール等のポリアルキレングリコール系化合物を反応させて、変性オルガノシリケート化合物として、配合してもよい。
樹脂成分（Ａ）は、顔料を分散させるために用いられる樹脂を含有していてもよい。顔料分散用樹脂としては、公知のアニオン系樹脂、ノニオン系樹脂、カチオン系樹脂を制限なく使用できる。白色顔料（Ｂ）の分散性を向上させるため、アニオン系樹脂、特にカルボン酸系樹脂を用いるのが好ましい。また、樹脂成分（Ａ）が水性の場合は、ポリカルボン酸系樹脂を、又有機溶剤型の場合は、水酸基含有カルボン酸エステル系樹脂を、用いるのが好ましい。分散用樹脂の配合量としては、塗料組成物に含まれる全顔料に対して１〜１０重量％程度が好適である。
白色顔料（Ｂ）
本発明の組成物に用いられる白色顔料（Ｂ）は、形成塗膜に遮熱性を付与するものであり、平均１次粒子径が５００〜２，０００ｎｍ、好ましくは５５０〜１，６００ｎｍ、より好ましくは６００〜１，４００ｎｍの範囲内であって、且つ屈折率が１．８０〜３．００、好ましくは１．９０〜２．８０、好ましくは１．９５〜２．７０の範囲内である。
白色顔料（Ｂ）は、上記粒子径及び屈折率を有することにより、塗膜中で波長７８０〜２，１００ｎｍ程度の近赤外線を効率的に反射・散乱することができ、遮熱性顔料としての効果を発揮することができる。効果的な白色顔料としては、二酸化チタン及び酸化亜鉛が挙げられ、これらの少なくとも一種を用いるのが好ましい。二酸化チタンを用いるのが特に好ましい。
白色顔料（Ｂ）の平均１次粒子径が５００ｎｍ未満では、可視光を効率よく散乱することはできるが、波長７８０〜２，１００ｎｍ程度の赤外線を透過してしまい、形成塗膜の遮熱効果が不十分になる。一方２，０００ｎｍを超えると、形成塗膜の隠蔽性及び光沢が低下するので、好ましくない。また、屈折率が１．８０未満では、形成塗膜の遮熱効果が十分でなく、又隠蔽性の点からも好ましくない。
ここで、平均１次粒子径とは、個々の独立した顔料粒子の粒子径の平均値である。一般に顔料粒子は凝集して存在しているので、通常の粒子径分布測定装置では粒子の凝集したものと個々の独立した粒子を区別して測定することは困難であるが、電子顕微鏡観察等により、独立した顔料粒子自体の平均粒子径を判定することが可能である。
本明細書において、顔料の「平均１次粒子径」は、電子顕微鏡観察により判定したものである。また、顔料の「屈折率」は、ＪＩＳ Ｋ ００６２に記載のアッベ屈折率計で測定した値である。
本発明において、白色顔料（Ｂ）としての二酸化チタンの結晶系は、上記した平均粒子径と屈折率の範囲であれば、ルチル型であってもアナターゼ型であってもよい。また、二酸化チタン表面を、酸化アルミニウム、酸化ジルコニウム、二酸化珪素等の無機酸化物；アミン、アルコール等の有機化合物などで被覆処理をしてもよい。
本発明においては、十分な遮熱効果を得る点から、形成塗膜の中に含まれる白色顔料（Ｂ）の顔料体積濃度（ｐｉｇｍｅｎｔ ｖｏｌｕｍｅ ｃｏｎｃｅｎｔｒａｔｉｏｎ；ＰＶＣ）が、５〜３０％程度であるのが好ましく、６〜２５％程度であるのがより好ましい。従って、このような顔料体積濃度となるように、樹脂成分（Ａ）に白色顔料（Ｂ）を配合する。顔料体積濃度は、塗膜中に含まれる顔料の体積百分率である。顔料体積濃度は、走査型電子顕微鏡により測定した塗膜断面の面積に対するその顔料の占める総面積の割合として算出することができる。
白色顔料（Ｃ）
本発明の遮熱性被膜形成用塗料組成物においては、平均１次粒子径が４００ｎｍ未満、好ましくは２００〜３００ｎｍ程度の白色顔料（Ｃ）をさらに含有することが、本発明組成物から形成される塗膜の下地隠蔽性を向上させることができる点から、好ましい。
かかる白色顔料（Ｃ）としては、二酸化チタン及び酸化亜鉛が挙げられ、これらの少なくとも一種を用いるのが好ましい。二酸化チタンを用いるのが特に好ましい。
上記二酸化チタン（Ｃ）の結晶型は、ルチル型、アナターゼ型のいずれであってもよいが、形成される塗膜の隠蔽性及び耐候性に優れる点から、ルチル型が好ましい。
着色顔料（Ｄ）
本発明の遮熱性被膜形成用塗料組成物は、着色顔料（Ｄ）をさらに含有することもできる。着色顔料（Ｄ）とは、塗膜に所望の色彩を与えるための顔料をいい、通常、無彩色顔料と有彩色顔料に分類することができる。
無彩色顔料としては、白色顔料及び黒色顔料等が挙げられる。白色顔料としては、例えば、鉛白、塩基性硫酸鉛、硫酸鉛、リトポン、硫化亜鉛、アンチモン白、白色顔料（Ｂ）及び白色顔料（Ｃ）以外の二酸化チタン又は二酸化亜鉛等が挙げられる。黒色顔料としては、例えば、アゾメチン系顔料、ペリレン系顔料、グラファイト等が挙げられる。
上記黒色顔料の内、ペリレン系顔料は、赤外線を吸収し難く、得られる塗膜の遮熱効果の低下が小さい点から、好ましい。一方、黒色顔料として、カーボンブラックを使用することもできるが、カーボンブラックは赤外線を吸収し易く、得られる塗膜の遮熱効果を大きく低下させるので、好ましくない。
有彩色顔料としては、前記無彩色顔料を除く着色顔料が包含される。例えば、黄色酸化鉄、チタンイエロー、モノアゾイエロー、縮合アゾイエロー、アゾメチンイエロー、ビスマスバナデート、ベンズイミダゾロン、イソインドリノン、イソインドリン、キノフタロン、ベンジジンイエロー、パーマネントイエロー等の黄色顔料；パーマネントオレンジ等の橙色顔料；赤色酸化鉄、ナフトールＡＳ系アゾレッド、アンサンスロン、アンスラキノニルレッド、ペリレンマルーン、キナクリドン系赤顔料、ジケトピロロピロール、ウォッチングレッド、パーマネントレッド等の赤色顔料；コバルト紫、キナクリドンバイオレット、ジオキサジンバイオレット等の紫色顔料；コバルトブルー、フタロシアニンブルー、スレンブルーなどの青色顔料；フタロシアニングリーンなどの緑色顔料等を挙げることができる。
該着色顔料（Ｄ）は、一種単独で使用してもよいし、必要に応じて２種以上を選択し組み合わせて使用してもよい。
本発明においては、着色顔料（Ｄ）として、補色関係にある複数の有彩色顔料を含有せしめることにより、上記白色顔料（Ｂ）の存在下においても、濃色の塗膜を形成することができ、幅広い明度の塗膜を得ることができる。
補色関係にある複数の有彩色顔料とは、例えば、マンセルの色相環でお互いほぼ反対の位置にある有彩色の２色の顔料が挙げられる。補色関係にある有彩色の組合せとして、例えば、赤と緑、青と橙色、黄と青紫、紫と黄緑などがあげられる。
遮熱性被膜形成用塗料組成物の配合組成及び調製方法
本発明の遮熱性被膜形成用塗料組成物において、白色顔料（Ｂ）の配合割合は、樹脂成分（Ａ）１００重量部に対して、１０〜１４０重量部程度が好ましく、１５〜１２０重量部程度がより好ましい。白色顔料（Ｂ）の配合量がこの範囲内であれば、形成塗膜中に含まれる白色顔料（Ｂ）の顔料体積濃度を５〜３０％程度の範囲内とすることができ、十分な遮熱効果を得ることができる。
本発明組成物が、白色顔料（Ｃ）を含有する場合、白色顔料（Ｃ）の配合割合は、樹脂成分（Ａ）１００重量部に対して、１０〜１４０重量部程度が好ましく、１５〜１２０重量部程度がより好ましい。白色顔料（Ｃ）の配合量がこの範囲内であれば、十分な下地隠蔽性を有する塗膜が得られる。
また、この場合、白色顔料（Ｂ）及び白色顔料（Ｃ）の重量比が、１０／９０〜９０／１０程度の範囲内であるのが好ましく、２０／８０〜８０／２０程度の範囲内であるのがより好ましい。この範囲内で白色顔料（Ｂ）及び白色顔料（Ｃ）を併用することにより、形成塗膜の遮熱効果と下地隠蔽性とを共に良好にすることができる。
本発明塗料組成物が着色顔料（Ｄ）を含有する場合、その含有量は限定されず、塗膜を所望の色彩とするのに必要な量を配合することができる。但し、着色顔料としてカーボンブラックを配合する場合は、得られる塗膜の遮熱効果が大きく低下しないように、樹脂成分（Ａ）１００重量部に対して、０．１重量部以下程度の少量に抑えることが望ましい。
本発明の遮熱性被膜形成用塗料組成物は、必要に応じて、体質顔料、防錆顔料、光輝性顔料、表面調整剤、界面活性剤、硬化触媒、分散剤、消泡剤、増粘剤、造膜助剤、防腐剤、凍結防止剤、硬化促進剤、反応遅延剤などの塗料用添加剤を含有することができる。
上記体質顔料としては、例えば、バリタ粉、沈降性硫酸バリウム、炭酸バリウム、炭酸カルシウム、石膏、クレー、シリカ、ホワイトカーボン、珪藻土、タルク、炭酸マグネシウム、アルミナホワイト、グロスホワイト等を挙げることができる。
本発明の遮熱性被膜形成用塗料組成物は、以上に述べた各成分を、公知の方法に従って、混合することにより、調製することができる。樹脂成分は、有機溶剤溶液、エマルション等の形態である場合は、そのまま混合することができる。また、顔料成分は、分散用樹脂と混合してペースト状としてから、混合してもよい。また、各成分の混合時に、必要に応じて、有機溶剤、水又はこれらの混合物を、加えてもよい。
本発明の塗料組成物は、固形分含量４０〜８０重量％程度の液状塗料組成物であるのが好ましい。また、液状塗料組成物は、有機溶剤型及び水性型のいずれであってもよい。
本発明組成物が含有する有機溶剤としては、各成分製造時に用いたものであってもよいし、各成分混合時に追加したものであってもよい。
本発明組成物に使用できる有機溶剤としては、例えば、ｎ−ヘキサン、ｎ−オクタン、２，２，２−トリメチルペンタン、イソオクタン、ｎ−ノナン、シクロヘキサン、メチルシクロヘキサン等の脂肪族炭化水素系溶剤；ベンゼン、トルエン、キシレン、エチルベンゼン等の芳香族炭化水素系溶剤；ミネラルスピリット、Ｃ９芳香族炭化水素含有率９５重量％以上の石油系炭化水素混合溶剤、石油エーテル、石油ベンジン、石油ナフサ等の石油系溶剤；メチルエチルケトン、メチルイソブチルケトン等のケトン系溶剤；酢酸エチル、酢酸イソブチル等のエステル系溶剤；エチレングリコールモノブチルエーテル等のエーテル系溶剤；イソプロピルアルコール、ｎ−ブチルアルコール、イソブチルアルコール等のアルコール系溶剤等を挙げることができる。
上記有機溶剤は、単独で、又は２種以上を混合して、用いることができる。また、必要に応じて、水と混合して用いることができる。
遮熱性被膜形成用塗料組成物の用途
本発明の遮熱性被膜形成用塗料組成物は、各種建築物等に遮熱性被膜を形成する場合において、単層仕上げ用の上塗り塗料、二層仕上げ用の上塗り塗料又は下塗り塗料として使用することができる。また、三層以上の複層塗膜用の中塗り塗料としても使用できる。
本発明塗料組成物を、上塗り塗料として使用する場合、着色顔料（Ｄ）を配合して、ＪＩＳ Ｚ ８７２９に規定されるＬ^＊ａ^＊ｂ^＊表色系に基づく明度（Ｌ^＊値）２０〜７０程度、好ましくは２２〜６８程度の塗膜を形成し得る組成物とすることによって、濃色の外観を有する塗膜を形成できる。
上記Ｌ^＊値の範囲の塗膜を得るためには、白色顔料（Ｂ）及び着色顔料（Ｄ）を、白色顔料（Ｂ）／着色顔料（Ｄ）の重量比で９５／５〜５／９５程度、好ましくは９０／１０〜６０／４０程度の範囲内にすることが好適である。
上記Ｌ^＊値は、塗膜の明度の指標であり、１００は純白を、０は純黒を示す。Ｌ^＊値は、公知の測色計を用いて、測定できる。
本発明の塗料組成物を、単層仕上げ用の上塗り塗料に使用する場合又は二層仕上げの下塗り塗料に使用する場合は、形成塗膜の破断伸び率が、２０℃で８０〜５００％程度であることが好ましく、１００〜４００％程度の範囲内であることがより好ましい。破断伸び率がこの範囲内であると、被塗面にワレが発生した場合に、形成塗膜が追随することができ、好適である。
また、本発明塗料組成物を、下塗り塗料として使用する場合、ＪＩＳ Ｚ ８７２９に規定されるＬ^＊ａ^＊ｂ^＊表色系に基づく明度（Ｌ^＊値）７０〜９８程度、好ましくは７５〜９７程度の塗膜を形成し得る組成物とすることにより、該塗膜の上層塗膜の明度等の色調に悪影響を及ぼさないことができる。
上記Ｌ^＊値の範囲の塗膜を得るためには、白色顔料（Ｂ）及び着色顔料（Ｄ）を、白色顔料（Ｂ）／着色顔料（Ｄ）の重量比で１００／０〜９０／１０程度とすることが好ましく、９９／１〜９５／５程度の範囲内とすることがより好ましい。
遮熱性被膜形成用塗料組成物を用いた塗装方法
本発明の遮熱性被膜形成用塗料組成物は、以下に示す種々の塗装方法において、好適に使用することができる。
被塗物及び塗装手段
本発明塗料組成物を適用する被塗物としては、遮熱性被膜を形成する必要がある被塗物であれば、限定されない。好ましい被塗物としては、建設構造物が挙げられる。建設構造物の具体例としては、ビル、住宅、工場、倉庫、店舗、学校等の建築物；石油用タンク、穀物用タンク等の貯蔵槽等が挙げられる。
また、被塗物の被塗面としては、建築物の外壁、屋根、タンクの外面等が好ましい。
上記被塗面の材質としては、金属、コンクリート、石膏ボード、スレート、サイディング材、磁器タイル、軽量気泡コンクリート、モルタル、レンガ、石材等の無機基材；木材、プラスチック等の有機基材が挙げられる。金属としては、鉄、亜鉛、鉄−亜鉛合金、アルミニウム等が挙げられる。
また、被塗面には、既に塗膜が設けられていてもよい。このような塗膜としては、アクリル樹脂系、アクリルウレタン樹脂系、ポリウレタン樹脂系、フッ素樹脂系、シリコンアクリル樹脂系、酢酸ビニル樹脂系、エポキシ樹脂系などの塗膜が挙げられる。
上記被塗面には、必要に応じて、公知のシーラー、下地調整剤等の塗膜を設けておいてもよい。
本発明塗料組成物の塗装手段としては、例えば、ローラー、エアスプレー、エアレススプレー、リシンガン、万能ガン、ハケなどの公知の塗装器具を挙げることができる。塗装後は、通常、常温で、乾燥又は乾燥及び架橋させて、乾燥塗膜を得る。但し、加熱等により、強制乾燥することもできる。
乾燥膜厚は、通常、１０〜２，０００μｍ程度、好ましくは２０〜１，５００μｍ程度の範囲内とすることができる。
本発明塗料組成物を用いる具体的な塗装方法としては、例えば、下記方法Ｉ、ＩＩ及びＩＩＩを挙げることができる。
方法Ｉは、被塗物に、本発明の上塗り塗料組成物を塗装する単層仕上げ塗装方法である。
上記単層仕上げで塗装する場合には、通常、乾燥膜厚が２００〜２，０００μｍ程度、好ましくは３００〜１，５００μｍ程度の範囲内となるように塗装することが好適である。この場合、上記乾燥膜厚の範囲内となるように、同じ塗料組成物を、複数回塗り重ねてもよい。
方法ＩＩは、被塗物に、下塗り塗料組成物を塗装後、該塗面上に本発明の上塗り塗料組成物を塗装する二層仕上げ塗装方法である。
方法ＩＩにおける下塗り塗料組成物としては、建築物の外壁、屋根等に塗装する下塗り塗料として用いられる公知の有機溶剤型塗料組成物及び水性塗料組成物をいずれも使用できる。例えば、アクリル樹脂エマルション、ウレタン樹脂エマルション、エポキシ樹脂エマルション、アルキド樹脂エマルション、脂肪酸変性アクリル樹脂エマルション等の樹脂成分及び顔料を含有する水性塗料組成物が好ましい。
方法ＩＩにおける下塗り塗料組成物の塗装方法としては、本発明塗料組成物の場合と同様の方法を採用できる。
方法ＩＩにおける下塗り塗料組成物は、通常、乾燥膜厚が１０〜３００μｍ程度、好ましくは２０〜２００μｍ程度の範囲内となるように塗装することが好適である。
また、方法ＩＩにおける本発明の上塗り塗料組成物は、通常、乾燥膜厚が１０〜１５０μｍ程度、好ましくは３０〜１００μｍ程度の範囲内となるように塗装することが好適である。
方法ＩＩＩは、被塗物に、本発明の下塗り塗料組成物を塗装後、該塗面上に上塗り塗料組成物を塗装する二層仕上げ塗装方法である。
方法ＩＩＩにおける本発明の下塗り塗料組成物は、通常、乾燥膜厚が２０〜１，０００μｍ程度、好ましくは４０〜８００μｍ程度の範囲内となるように塗装することが好適である。
また、方法ＩＩＩにおける上塗り塗料組成物としては、建築物の外壁、屋根等に塗装する上塗り塗料として用いられる公知の有機溶剤型塗料組成物及び水性塗料組成物をいずれも使用できる。例えば、アクリル樹脂エマルション、ウレタン樹脂エマルション、脂肪酸変性アクリル樹脂エマルション、フッ素樹脂エマルション、酢酸ビニル樹脂エマルション等の樹脂成分及び顔料を含有する水性塗料組成物が好ましい。また、建築物の外壁、屋根等を濃色の外観とする場合には、該上塗り塗料組成物が、ペリレン系顔料を含有する塗料組成物であることが、本発明下塗り塗料組成物の塗膜及び該上塗り塗料組成物の塗膜からなる二層塗膜の遮熱効果を低下させない点から、好ましい。
方法ＩＩＩにおける上塗り塗料組成物の塗装方法としては、本発明塗料組成物の場合と同様の方法を採用できる。
方法ＩＩＩにおける上塗り塗料組成物は、通常、乾燥膜厚が１０〜３００μｍ程度、好ましくは２０〜２００μｍ程度の範囲内となるように塗装することが好適である。
また、上記方法Ｉ〜ＩＩＩ以外の塗装方法として、被塗物に、本発明の下塗り塗料組成物を塗装後、該塗面上に本発明の上塗り塗料組成物を塗装する二層仕上げ塗装方法も採用できる。
更に、被塗物に、公知の下塗り塗料組成物を塗装後、本発明の塗料組成物を中塗り塗料組成物として塗装し、更にこの中塗り塗面上に公知の上塗り塗料組成物を塗装する三層仕上げ塗装方法も採用できる。
かくして、本発明塗料組成物を用いて、各種被塗物上に、遮熱効果等に優れた塗膜を形成することができる。  According to the coating composition for forming a heat-shielding film of the present invention, the refractive index of the film of the resin component (A) and the average particle diameter and refractive index of the white pigment (B) are adjusted within specific ranges, respectively. The following remarkable effects can be obtained.
  (1) A coating film having excellent heat shielding effect and sufficient base concealing property and gloss can be formed in a single layer or multiple layers on various objects to be coated such as buildings. Therefore, it can contribute to suppression of the temperature rise inside the article to be coated.
  (2) By selecting the type of the resin component (A), functions such as contamination resistance and weather resistance can be imparted to the formed coating film.
  (3) By making the coating composition contain a color pigment and using it as a top coating, it is possible to obtain a coating film that is excellent in heat-shielding effect and rich in color variations such as dark colors. Therefore, by applying to the outer wall, roof, etc. of the object to be coated such as a building, an increase in temperature inside the object to be coated can be suppressed, and in addition, an appearance with excellent cosmetics can be obtained.
  (4) By adjusting the coating film formed from the coating composition to have a specific lightness and using it as an undercoating paint, it is possible to form an undercoating coating film having excellent heat shielding effect and concealing property. Therefore, it is possible to form a multilayer coating film having a good appearance and excellent heat-shielding effect without adversely affecting the color tone of the coating film of the top coating applied on the undercoat coating film. According to such a multilayer coating film, for example, even if the top coating film has a deep color appearance, the multilayer coating film as a whole retains the appearance of the object to be coated without causing a bad appearance. However, the internal temperature rise can be suppressed.
  Coating composition for forming a heat-shielding film
  The coating composition for forming a heat-shielding film of the present invention has a resin component (A) that forms a film having a refractive index in the range of 1.30 to 1.60, and an average primary particle diameter of 500 to 2,000 nm. The white pigment (B) within the range and having a refractive index of 1.80 to 3.00 is contained.
  In the coating composition of the present invention, by combining the white pigment (B) with the resin component (A), the action of reflecting and scattering the infrared rays of the white pigment (B) is effectively exhibited, The heat shielding effect of the obtained coating film will be excellent. Here, the said effect | action of a white pigment (B) is an effect | action which reflects and scatters especially the near infrared rays with a wavelength of about 780-2,100nm efficiently.
  Resin component (A)
  The resin component (A) has a refractive index of 1.30 to 1.60, preferably 1.35 to 1.58, more preferably 1.40 to 1.55.
  When the refractive index of the resin component (A) film exceeds 1.60, not only the efficiency of reflection / scattering of infrared rays by the white pigment (B) is lowered, but also the concealability and appearance of the coating film may be lowered. Therefore, it is not preferable.
  Further, in order for the white pigment (B) to reflect and scatter infrared rays efficiently, the refractive index of the resin component (A) film needs to be smaller than the refractive index of the white pigment (B). The value obtained by subtracting the refractive index of the resin component (A) film from the refractive index of the white pigment (B) is 0.20 or more, preferably 0.45 to 1.40, more preferably 0.80 to 1.00. It is. If the refractive index difference is less than 0.20, the ratio of infrared rays to be transmitted increases, which is not preferable.
  In this specification, the refractive index of the coating film of the resin component (A) is obtained by preparing a free coating film of the resin component (A) and measuring it with an Abbe refractometer described in JIS K0062.
  The resin component (A) is not limited as long as the film formed by the component has a refractive index in the above range. The resin component (A) may be a water-soluble or water-dispersible resin, a resin that is soluble or dispersible in an organic solvent, or a powder resin. The resin component (A) is preferably a resin that can be dried at room temperature because the coating composition of the present invention is mainly used for painting outdoors such as the outer surface of a building or the like.
  In addition, the resin component (A) may be either a crosslinked resin or a non-crosslinked resin.
  The crosslinkable resin is usually used in a state in which a self-crosslinkable resin or a crosslinkable functional group-containing resin and a crosslinking agent are dissolved or dispersed in a medium. As the medium, water and / or an organic solvent is used. A coating composition containing a crosslinkable resin undergoes a crosslinking reaction when the medium volatilizes after coating, thereby forming a three-dimensional crosslinked coating film.
  On the other hand, the non-crosslinked resin is usually used in a state dissolved or dispersed in a medium. As the medium, water and / or an organic solvent is used. The coating composition containing the non-crosslinked resin forms a coating film by volatilization of the medium after coating. Examples of the non-crosslinked resin include cellulose derivatives, acrylic resins, urethane resins, vinyl chloride resins, fluororesins, alkyd resins, vinyl acetate resins, and styrene-butadiene resins.
  As the resin component (A), it is desirable to use a crosslinked acrylic resin or a non-crosslinked acrylic resin because the gloss of the coating film formed from the composition of the present invention is good.
  In addition, as the resin component (A), a combination of a carbonyl group-containing acrylic copolymer and a hydrazine derivative that is a crosslinking agent thereof, a maleimide group-containing acrylic copolymer, an unsaturated fatty acid-modified acrylic copolymer, or the like Is preferred. The carbonyl group-containing acrylic copolymer may be used alone as a non-crosslinked resin.
  The carbonyl group-containing acrylic copolymer as the resin component (A) is preferably used as an emulsion.
  The carbonyl group-containing acrylic copolymer emulsion is prepared, for example, according to a general emulsion polymerization method, in the presence of a surfactant as an emulsifier, and a carbonyl group-containing ethylenically unsaturated monomer and other ethylenically unsaturated monomers. Can be easily produced by copolymerization.
  The carbonyl group-containing ethylenically unsaturated monomer is a monomer having, in one molecule, at least one carbonyl-containing group selected from an aldehyde group and a keto group and a polymerizable double bond. Examples of the monomer include (meth) acrolein, formylstyrene, a vinyl alkyl ketone having 4 to 7 carbon atoms, acetoacetoxyethyl (meth) acrylate, diacetone (meth) acrylamide, and the like. Examples of the vinyl alkyl ketone having 4 to 7 carbon atoms include vinyl methyl ketone, vinyl ethyl ketone, and vinyl butyl ketone.
  Other ethylenically unsaturated monomers include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, pentyl (meth) Alkyl (meth) acrylates such as acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate; alicyclic rings such as cyclohexyl (meth) acrylate and isobornyl (meth) acrylate Formula (meth) acrylate; Aralkyl (meth) acrylate such as benzyl (meth) acrylate; Alkoxyalkyl (meth) acrylate such as 2-methoxyethyl (meth) acrylate and 2-ethoxyethyl (meth) acrylate Relate; hydroxyalkyl (meth) acrylates such as hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate; vinyl ester compounds such as vinyl acetate and vinyl propionate; vinyl aromatic compounds such as styrene and α-methylstyrene; Examples thereof include fluoroalkyl (meth) acrylate, glycidyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, (meth) acrylic acid, (meth) acrylamide, (meth) acrylonitrile and the like. Among these, styrene, alkyl (meth) acrylate having an alkyl group having 1 to 8 carbon atoms, (meth) as a preferable monomer from the viewpoint of the refractive index and copolymerizability of the copolymer film obtained. Acrylic acid, (meth) acrylamide, etc. can be mentioned.
  By combining the carbonyl group-containing acrylic copolymer emulsion with a hydrazine derivative, a resin component that is crosslinked at room temperature can be obtained, and a crosslinked coating film having excellent water resistance, weather resistance, and the like can be formed.
  Examples of the hydrazine derivative include a compound having at least two functional groups selected from a hydrazide group, a semicarbazide group, and a hydrazone group per molecule. Two or more functional groups may be the same or different.
  Examples of the compound having two or more hydrazide groups per molecule include succinic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, glutaric acid dihydrazide, adipic acid dihydrazide, and sebacic acid dihydrazide. Dihydrazide of acid; monohydric unsaturated dicarboxylic acid dihydrazide such as maleic acid dihydrazide, fumaric acid dihydrazide, itaconic acid dihydrazide; phthalic acid, terephthalic acid or isophthalic acid dihydrazide; pyromellitic acid dihydrazide, trihydrazide or tetrahydrazide; Nitrilotriacetic acid trihydrazide, citric acid trihydrazide, 1,2,4-benzenetrihydrazide; ethylenediaminetetraacetic acid tetrahydrazide, 1,4,5,8-naphthoic acid tet Hydrazides; such as carboxylic acid lower alkyl ester group oligomer is reacted with hydrazine or hydrazine hydrate comprising polyhydrazide having the like.
  As the hydrazide compound, for example, dihydrazides of saturated fatty acid dicarboxylic acids such as adipic acid dihydrazide and succinic acid dihydrazide are suitable.
  Examples of the compound having two or more semicarbazide groups per molecule include a dihydrazide carbonate, a bissemicarbazide; a diisocyanate compound or a polyisocyanate compound derived therefrom, and an N, N-substituted hydrazine or the above hydrazide reacted excessively. An aqueous polyfunctional semicarbazide obtained by excessive reaction of the dihydrazide with an isocyanate group in a reaction product of the polyisocyanate compound and a hydrophilic group-containing active hydrogen compound; the polyfunctional semicarbazide and the aqueous polyfunctional semicarbazide And the like. Examples of the diisocyanate compound include hexamethylene diisocyanate and isophorone diisocyanate. N, N-substituted hydrazine includes N, N-dimethylhydrazine and the like. Examples of the hydrophilic group-containing active hydrogen compound include polyether polyols and polyethylene glycol monoalkyl ethers.
  As a compound having two or more hydrazone groups per molecule, for example, bisacetyldihydrazone can be preferably used.
  The hydrazine derivatives can be used alone or in combination of two or more. The amount of the hydrazine derivative used is 0 with respect to the nonvolatile content of the carbonyl group-containing acrylic copolymer emulsion in order to make the refractive index of the resin component (A) film in the range of 1.30 to 1.60. Within the range of about 1 to 10.0% by weight is preferable.
  The maleimide group-containing acrylic copolymer that is the resin component (A) is preferably used as an emulsion. The maleimide group-containing acrylic copolymer emulsion has a property that the maleimide group is dimerized by light irradiation, so that a self-crosslinking reaction proceeds at room temperature under sunlight irradiation.
  The emulsion is obtained, for example, by copolymerizing a maleimide group-containing ethylenically unsaturated monomer and other ethylenically unsaturated monomers in the presence of a surfactant as an emulsifier according to a general emulsion polymerization method. It can be manufactured easily.
  As the maleimide group-containing ethylenically unsaturated monomer, it is preferable to use compounds represented by the following formulas (1) and (2).

  In each formula, R¹And R²Independently represents a hydrogen atom or a methyl group. R³And R⁴Independently represents an alkyl group having 4 or less carbon atoms. n shows the integer of 1-6.
  As other ethylenically unsaturated monomers, those listed as other ethylenically unsaturated monomers used for the production of the carbonyl group-containing acrylic copolymer emulsion can be used.
  As the resin component (A), a carbonyl group-containing acrylic copolymer emulsion and a maleimide group-containing acrylic copolymer emulsion can be used in combination. The combined ratio in this case is in the range of about 3/97 to 97/3, preferably about 10/90 to 90/10 in terms of the weight ratio of the former / the latter. In the case of this combined use, the hydrazine derivative can be used in combination with the carbonyl group-containing acrylic resin.
  As the resin component (A), an unsaturated fatty acid-modified acrylic resin that is soluble in an organic solvent can be preferably used. The unsaturated fatty acid-modified acrylic resin is self-crosslinked by oxidative polymerization at room temperature. Moreover, the unsaturated fatty-acid component in this resin can suppress effectively the fall of the coating-film gloss which may generate | occur | produce by white pigment (B) mixing | blending.
  The unsaturated fatty acid-modified acrylic resin is obtained by, for example, copolymerizing an epoxy group-containing ethylenically unsaturated monomer and another ethylenically unsaturated monomer in the presence of an organic solvent to produce an epoxy group-containing acrylic copolymer. It can be obtained by preparing and adding an unsaturated fatty acid to the epoxy group.
  The epoxy group-containing ethylenically unsaturated monomer is a monomer having at least one epoxy group and a polymerizable double bond in one molecule. Examples of the monomer include glycidyl (meth) acrylate, β-methylglycidyl (meth) acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate, 3,4-epoxycyclohexylethyl (meth) acrylate, 3, Examples include 4-epoxycyclohexylpropyl (meth) acrylate and allyl glycidyl ether.
  As other ethylenically unsaturated monomers, those listed as other ethylenically unsaturated monomers used for the production of the carbonyl group-containing acrylic copolymer emulsion can be used.
  The unsaturated fatty acid is introduced in order to oxidize and cure the formed coating film. Examples of the fatty acid include fish oil fatty acid, dehydrated castor oil fatty acid, safflower oil fatty acid, linseed oil fatty acid, soybean oil fatty acid, sesame oil fatty acid, poppy oil fatty acid, eno oil fatty acid, hemp oil fatty acid, grape kernel oil fatty acid, corn oil Examples include fatty acid, tall oil fatty acid, sunflower oil fatty acid, cottonseed oil fatty acid, walnut oil fatty acid, rubber seed oil fatty acid and the like.
  The fatty acid-modified acrylic resin may be modified with a silicon resin or the like for the purpose of improving weather resistance.
  The resin component (A) is mainly composed of a resin containing a hydroxyl group in a resin such as a fluororesin, an acrylic resin, a polyester resin, an alkyd resin, a urethane resin, or an epoxy resin, and a crosslinking agent such as polyisocyanate. A two-component resin composition that is mixed immediately before use can also be used. For example, a urethane curable two-component paint in which a polyisocyanate curing agent is used in combination with a base resin (main agent) containing a hydroxyl group-containing acrylic resin can be preferably used.
  The resin component (A) can contain an organosilicate compound as an antifouling agent, if necessary. With this compound, the formed coating film becomes hydrophilic, and the surface is easily washed with rainwater or the like, so that an advantage that it becomes difficult to become dirty is obtained.
  As said organosilicate compound, the linear condensate represented by following formula (3) can be mention | raise | lifted, for example.

  Where R⁵Independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms. m shows the integer of 1-100.
  Examples of the hydrocarbon group having 1 to 10 carbon atoms include methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, t-butyl group, n-pentyl group, Alkyl groups such as i-pentyl group, n-hexyl group, i-hexyl group and n-octyl group; aryl groups such as phenyl group and the like are preferable.
  As the organosilicate compound of the above formula (3), R⁵Is more preferably a lower alkyl group having 1 to 4 carbon atoms and m being 2 to 15.
  The organosilicate compound includes a branched compound or a cyclic compound in addition to the linear compound represented by the formula (3).
  When the resin component (B) is aqueous, the organosilicate compound may be blended as a modified organosilicate compound by reacting a polyalkylene glycol compound such as polyethylene glycol or polypropylene glycol.
  The resin component (A) may contain a resin used for dispersing the pigment. As the pigment dispersing resin, known anionic resins, nonionic resins, and cationic resins can be used without limitation. In order to improve the dispersibility of the white pigment (B), it is preferable to use an anionic resin, particularly a carboxylic acid resin. When the resin component (A) is aqueous, it is preferable to use a polycarboxylic acid resin, and when it is an organic solvent type, a hydroxyl group-containing carboxylic acid ester resin is preferably used. The blending amount of the dispersing resin is preferably about 1 to 10% by weight with respect to the total pigment contained in the coating composition.
  White pigment (B)
  The white pigment (B) used in the composition of the present invention imparts heat shielding properties to the formed coating film, and the average primary particle diameter is 500 to 2,000 nm, preferably 550 to 1,600 nm, more preferably. Has a refractive index of 1.80 to 3.00, preferably 1.90 to 2.80, preferably 1.95 to 2.70.
  Since the white pigment (B) has the above particle diameter and refractive index, it can efficiently reflect and scatter near infrared rays having a wavelength of about 780 to 2,100 nm in the coating film, and is effective as a heat shielding pigment. Can be demonstrated. Effective white pigments include titanium dioxide and zinc oxide, and it is preferable to use at least one of these. It is particularly preferable to use titanium dioxide.
  If the average primary particle size of the white pigment (B) is less than 500 nm, visible light can be efficiently scattered, but infrared rays having a wavelength of about 780 to 2,100 nm are transmitted, and the heat-shielding effect of the formed coating film Becomes insufficient. On the other hand, when it exceeds 2,000 nm, the concealability and gloss of the formed coating film are lowered, which is not preferable. Moreover, if the refractive index is less than 1.80, the heat-shielding effect of the formed coating film is not sufficient, and it is not preferable from the viewpoint of concealment.
  Here, the average primary particle diameter is an average value of the particle diameters of the individual independent pigment particles. In general, pigment particles are present in an aggregated state, so it is difficult to distinguish and measure individual and independent particles with an ordinary particle size distribution measuring device. It is possible to determine the average particle size of the independent pigment particles themselves.
  In the present specification, the “average primary particle size” of the pigment is determined by observation with an electron microscope. The “refractive index” of the pigment is a value measured by an Abbe refractometer described in JIS K0062.
  In the present invention, the crystal system of titanium dioxide as the white pigment (B) may be a rutile type or an anatase type as long as the average particle diameter and refractive index are in the above ranges. Further, the surface of titanium dioxide may be coated with an inorganic oxide such as aluminum oxide, zirconium oxide or silicon dioxide; an organic compound such as amine or alcohol.
  In the present invention, from the viewpoint of obtaining a sufficient heat shielding effect, the pigment volume concentration (PVC) of the white pigment (B) contained in the formed coating film is about 5 to 30%. Preferably, it is more preferably about 6 to 25%. Accordingly, the white pigment (B) is blended with the resin component (A) so as to obtain such a pigment volume concentration. The pigment volume concentration is a volume percentage of the pigment contained in the coating film. The pigment volume concentration can be calculated as the ratio of the total area occupied by the pigment to the area of the cross section of the coating film measured by a scanning electron microscope.
  White pigment (C)
  The coating composition for forming a heat-shielding film of the present invention is formed from the composition of the present invention to further contain a white pigment (C) having an average primary particle size of less than 400 nm, preferably about 200 to 300 nm. It is preferable from the point which can improve the base concealment property of a coating film.
  Examples of the white pigment (C) include titanium dioxide and zinc oxide, and it is preferable to use at least one of these. It is particularly preferable to use titanium dioxide.
  The crystal form of the titanium dioxide (C) may be either a rutile type or an anatase type, but the rutile type is preferred from the viewpoint of excellent concealability and weather resistance of the coating film to be formed.
  Color pigment (D)
  The coating composition for forming a heat-shielding film of the present invention can further contain a color pigment (D). The color pigment (D) refers to a pigment for imparting a desired color to a coating film, and can be generally classified into an achromatic color pigment and a chromatic color pigment.
  Examples of the achromatic pigment include a white pigment and a black pigment. Examples of white pigments include lead white, basic lead sulfate, lead sulfate, lithopone, zinc sulfide, antimony white, titanium dioxide or zinc dioxide other than white pigment (B) and white pigment (C). Examples of black pigments include azomethine pigments, perylene pigments, and graphite.
  Among the black pigments, perylene pigments are preferable because they hardly absorb infrared rays and have a small decrease in the heat shielding effect of the resulting coating film. On the other hand, carbon black can also be used as the black pigment, but carbon black is not preferable because it easily absorbs infrared rays and greatly reduces the heat shielding effect of the resulting coating film.
  The chromatic color pigment includes colored pigments excluding the achromatic color pigment. For example, yellow pigments such as yellow iron oxide, titanium yellow, monoazo yellow, condensed azo yellow, azomethine yellow, bismuth vanadate, benzimidazolone, isoindolinone, isoindoline, quinophthalone, benzidine yellow, permanent yellow, etc .; permanent orange, etc. Orange pigment; red iron oxide, naphthol AS azo red, ansanthrone, anthraquinonyl red, perylene maroon, quinacridone red pigment, diketopyrrolopyrrole, watching red, permanent red, etc .; cobalt violet, quinacridone violet, di Examples include purple pigments such as oxazine violet; blue pigments such as cobalt blue, phthalocyanine blue, and selenium blue; green pigments such as phthalocyanine green.
  The color pigment (D) may be used alone or in combination of two or more as necessary.
  In the present invention, a dark coating film can be formed even in the presence of the white pigment (B) by incorporating a plurality of chromatic pigments having a complementary color relationship as the coloring pigment (D). A coating film with a wide range of brightness can be obtained.
  Examples of the plurality of chromatic color pigments having a complementary color relationship include chromatic two-color pigments located at positions almost opposite to each other in the Munsell hue ring. Examples of combinations of chromatic colors having a complementary color relationship include red and green, blue and orange, yellow and blue-violet, purple and yellow-green.
  Composition and preparation method of coating composition for forming thermal barrier coating
  In the coating composition for forming a heat-shielding film of the present invention, the blending ratio of the white pigment (B) is preferably about 10 to 140 parts by weight with respect to 100 parts by weight of the resin component (A), and about 15 to 120 parts by weight. Is more preferable. If the blending amount of the white pigment (B) is within this range, the pigment volume concentration of the white pigment (B) contained in the formed coating film can be within the range of about 5 to 30%, and sufficient shielding is achieved. A thermal effect can be obtained.
  When this invention composition contains a white pigment (C), about 10-140 weight part is preferable with respect to 100 weight part of resin components (A), and the mixture ratio of white pigment (C) is 15-120. About parts by weight are more preferable. When the blending amount of the white pigment (C) is within this range, a coating film having a sufficient base concealing property can be obtained.
  In this case, the weight ratio of the white pigment (B) and the white pigment (C) is preferably in the range of about 10/90 to 90/10, and in the range of about 20/80 to 80/20. More preferably. By using the white pigment (B) and the white pigment (C) in this range, both the heat shielding effect of the formed coating film and the base concealing property can be improved.
  When this invention coating composition contains a coloring pigment (D), the content is not limited, The quantity required in order to make a coating film into a desired color can be mix | blended. However, when carbon black is blended as a color pigment, the amount of the resin component (A) is reduced to about 0.1 parts by weight or less with respect to 100 parts by weight of the resin component (A) so that the heat shielding effect of the obtained coating film is not greatly reduced. It is desirable to suppress.
  The coating composition for forming a heat-shielding film of the present invention is, if necessary, extender pigment, rust preventive pigment, glitter pigment, surface conditioner, surfactant, curing catalyst, dispersant, antifoaming agent, thickener. In addition, coating additives such as a film-forming auxiliary, a preservative, an antifreezing agent, a curing accelerator, and a reaction retarder can be contained.
  Examples of the extender pigment include barita powder, precipitated barium sulfate, barium carbonate, calcium carbonate, gypsum, clay, silica, white carbon, diatomaceous earth, talc, magnesium carbonate, alumina white, and gloss white.
  The coating composition for forming a heat-shielding film of the present invention can be prepared by mixing the above-described components according to a known method. When the resin component is in the form of an organic solvent solution, an emulsion, or the like, it can be mixed as it is. The pigment component may be mixed with the dispersing resin to form a paste and then mixed. Moreover, when mixing each component, you may add an organic solvent, water, or these mixtures as needed.
  The coating composition of the present invention is preferably a liquid coating composition having a solid content of about 40 to 80% by weight. The liquid coating composition may be either an organic solvent type or an aqueous type.
  As an organic solvent which this invention composition contains, what was used at the time of each component manufacture may be used, and what was added at the time of each component mixing may be used.
  Examples of the organic solvent that can be used in the composition of the present invention include aliphatic hydrocarbon solvents such as n-hexane, n-octane, 2,2,2-trimethylpentane, isooctane, n-nonane, cyclohexane, and methylcyclohexane; Aromatic hydrocarbon solvents such as benzene, toluene, xylene, ethylbenzene; mineral spirits, petroleum hydrocarbon mixed solvents with a C9 aromatic hydrocarbon content of 95 wt% or more, petroleum ethers such as petroleum ether, petroleum benzine, and petroleum naphtha Solvents; ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone; ester solvents such as ethyl acetate and isobutyl acetate; ether solvents such as ethylene glycol monobutyl ether; alcohol solvents such as isopropyl alcohol, n-butyl alcohol and isobutyl alcohol Cite Can.
  The said organic solvent can be used individually or in mixture of 2 or more types. Moreover, it can mix with water as needed.
  Use of coating composition for thermal barrier coating formation
  The coating composition for forming a heat-shielding film of the present invention can be used as a top-coat paint for a single-layer finish, a top-coat paint or a bottom-coat paint for a two-layer finish when forming a heat-shielding film on various buildings. it can. Moreover, it can be used as an intermediate coating for a multilayer coating film having three or more layers.
  When the coating composition of the present invention is used as a top coating, a coloring pigment (D) is blended, and L defined in JIS Z 8729^*a^*b^*Lightness based on the color system (L^*Value) A coating film having a dark appearance can be formed by forming a composition capable of forming a coating film of about 20 to 70, preferably about 22 to 68.
  L above^*In order to obtain a coating film having a value in the range, the white pigment (B) and the color pigment (D) are preferably about 95/5 to 5/95 by weight ratio of white pigment (B) / color pigment (D). Is preferably in the range of about 90/10 to 60/40.
  L above^*The value is an indicator of the brightness of the coating film, where 100 indicates pure white and 0 indicates pure black. L^*The value can be measured using a known colorimeter.
  When the coating composition of the present invention is used as a top coat for a single layer finish or used as a bottom coat for a two-layer finish, the elongation at break of the formed coating film is about 80 to 500% at 20 ° C. It is preferable that it is within a range of about 100 to 400%. When the elongation at break is within this range, it is preferable that the formed coating film can follow when cracking occurs on the surface to be coated.
  Further, when the coating composition of the present invention is used as an undercoat paint, L defined in JIS Z 8729^*a^*b^*Lightness based on the color system (L^*Value) By making the composition capable of forming a coating film of about 70 to 98, preferably about 75 to 97, the color tone such as the brightness of the upper coating film of the coating film can be prevented from being adversely affected.
  L above^*In order to obtain a coating film having a value in the range, the white pigment (B) and the color pigment (D) are about 100/0 to 90/10 in weight ratio of white pigment (B) / color pigment (D). It is more preferable that it is in the range of about 99/1 to 95/5.
  Coating method using coating composition for forming thermal barrier coating
  The coating composition for forming a heat-shielding film of the present invention can be suitably used in various coating methods shown below.
  Workpiece and painting means
  The coating object to which the coating composition of the present invention is applied is not limited as long as it is a coating object that needs to form a heat-shielding film. A preferable structure is a construction structure. Specific examples of the construction structure include buildings such as buildings, houses, factories, warehouses, stores, and schools; storage tanks such as oil tanks and grain tanks.
  Moreover, as a coating surface of a coating object, the outer wall of a building, a roof, the outer surface of a tank, etc. are preferable.
  Examples of the material to be coated include inorganic base materials such as metal, concrete, gypsum board, slate, siding material, porcelain tile, lightweight cellular concrete, mortar, brick and stone materials; organic base materials such as wood and plastic. . Examples of the metal include iron, zinc, iron-zinc alloy, aluminum and the like.
  Moreover, the coating surface may already be provided in the to-be-coated surface. Examples of such a coating film include acrylic resin-based, acrylic urethane resin-based, polyurethane resin-based, fluororesin-based, silicon acrylic resin-based, vinyl acetate resin-based, and epoxy resin-based coating films.
  A coating film such as a known sealer or a base conditioner may be provided on the surface to be coated, if necessary.
  Examples of the coating means for the coating composition of the present invention include known coating instruments such as rollers, air sprays, airless sprays, lysing guns, universal guns, and brushes. After coating, it is usually dried or dried and crosslinked at room temperature to obtain a dry coating film. However, forced drying can also be performed by heating or the like.
  The dry film thickness is usually in the range of about 10 to 2,000 μm, preferably about 20 to 1,500 μm.
  Specific coating methods using the coating composition of the present invention include, for example, the following methods I, II and III.
  Method I is a single-layer finish coating method in which the top coating composition of the present invention is applied to an object to be coated.
  In the case of painting with the above single-layer finish, it is usually preferred that the dry film thickness is about 200 to 2,000 μm, preferably about 300 to 1,500 μm. In this case, the same coating composition may be applied a plurality of times so as to be within the range of the dry film thickness.
  Method II is a two-layer finish coating method in which an undercoating composition is applied to an object to be coated, and then the overcoating composition of the present invention is applied onto the coated surface.
  As the undercoat paint composition in Method II, any of known organic solvent-type paint compositions and aqueous paint compositions used as undercoat paints to be applied to the outer walls of buildings, roofs, and the like can be used. For example, an aqueous coating composition containing a resin component and a pigment such as an acrylic resin emulsion, a urethane resin emulsion, an epoxy resin emulsion, an alkyd resin emulsion, and a fatty acid-modified acrylic resin emulsion is preferable.
  As the coating method of the undercoat coating composition in Method II, the same method as in the coating composition of the present invention can be employed.
  The undercoat coating composition in Method II is usually suitably applied so that the dry film thickness is in the range of about 10 to 300 μm, preferably about 20 to 200 μm.
  In addition, the top coating composition of the present invention in Method II is usually applied so that the dry film thickness is in the range of about 10 to 150 μm, preferably about 30 to 100 μm.
  Method III is a two-layer finish coating method in which an undercoat coating composition of the present invention is applied to an object to be coated, and then a top coating composition is applied onto the coated surface.
  In general, the undercoat coating composition of the present invention in Method III is preferably applied so that the dry film thickness is in the range of about 20 to 1,000 μm, preferably about 40 to 800 μm.
  In addition, as the top coating composition in Method III, any of known organic solvent-type coating compositions and water-based coating compositions that are used as top coatings to be applied to the outer walls of buildings, roofs, and the like can be used. For example, an aqueous coating composition containing a resin component and a pigment such as an acrylic resin emulsion, a urethane resin emulsion, a fatty acid-modified acrylic resin emulsion, a fluororesin emulsion, and a vinyl acetate resin emulsion is preferable. Further, when the outer wall of the building, the roof or the like has a dark appearance, the coating film of the undercoating composition of the present invention is such that the overcoating composition is a coating composition containing a perylene pigment. And the point which does not reduce the heat-shielding effect of the two-layer coating film which consists of a coating film of this top coat coating composition is preferable.
  As the coating method of the top coating composition in Method III, the same method as in the coating composition of the present invention can be employed.
  The top coating composition in Method III is usually applied so that the dry film thickness is in the range of about 10 to 300 μm, preferably about 20 to 200 μm.
  Further, as a coating method other than the above-mentioned methods I to III, there is also a two-layer finish coating method in which the undercoating composition of the present invention is applied to an object to be coated and then the overcoating composition of the present invention is coated on the coated surface. Can be adopted.
  Further, after applying a known undercoating composition to the object to be coated, the coating composition of the present invention is applied as an intermediate coating composition, and further, a known topcoating composition is applied onto this intermediate coating surface. A three-layer finish painting method can also be adopted.
  Thus, using the coating composition of the present invention, it is possible to form a coating film having an excellent heat shielding effect on various objects to be coated.

  FIG. 1 is a cross-sectional view showing an outline of a temperature measuring device used for a test of a heat shielding effect of a coating film. In FIG. 1, reference numeral 1 is a light source, 2 is a free coating film for testing, 3 is a box made of expanded polystyrene, and 4 to 6 are thermocouple thermometers.

脂肪酸変性アクリル樹脂（ｃ）の製造
製造例１１
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℃まで撹拌下に昇温した。次に、温度を１１５℃に保ちながら、スチレン２５部、ｎ−ブチルメタクリレート１５部、ｉ−ブチルメタクリレート２０部、２−エチルヘキシルアクリレート２０部、グリシジルメタクリレート２０部及び２，２’−アゾビスイソブチロニトリル１部の混合物を、４時間かけて滴下した。ついで、１１５℃で２時間熟成した後、１４０℃に昇温してからアマニ油脂肪酸３０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、１６０℃で５時間保持して脂肪酸の付加反応を行った。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、キシレン４５部を加えて希釈して不揮発分５０重量％の褐色透明で粘調な脂肪酸変性共重合体溶液を得た。次に、１００℃まで冷却し、フラスコに水分離器を装備し、シリコン樹脂（シラノール基を有するポリアルキルフェニルシロキサン、商品名「ＳＨ−６０１８」、東レ・ダウコーニング・シリコーン（株）製）２０部、ミネラルスピリット１４部、キシレン６部及び反応触媒としてのテトラ−ｎ−ブチルチタネート０．２０部を加え、１６５℃まで昇温し、還流系中で水分離器で水を分離しながら５時間反応させて不揮発分約５０重量％の褐色透明で粘調なシリコン含有脂肪酸変性アクリル樹脂（ｃ）を得た。
アクリル共重合体エマルション（ｄ）の製造
製造例１２
フラスコに、脱イオン水３６部およびアニオン性界面活性剤（注１１）０．３６部を入れ、窒素置換後、８０℃まで加温し、内液を８０℃に維持しながら０．１部の過硫酸アンモニウムを加えた後、下記組成の単量体エマルションを３時間にわたって滴下した。
単量体エマルション組成
脱イオン水 ５２．４部
アクリル酸 ０．５部
スチレン １７．５部
メチルメタクリレート ２８部
２−エチルヘキシルアクリレート １８部
ｎ−ブチルアクリレート ３６部
アニオン性界面活性剤（注１１） ９．６部
過硫酸アンモニウム ０．２部
滴下終了後３０分より３０分間に渡り、０．１部の過硫酸アンモニウムを１部の脱イオン水に溶かした溶液を滴下し、さらに２時間８０℃に保ってエマルション（ｄ）を得た。
樹脂エマルション（Ｒ−１）の製造
製造例１３
２リットルのステンレス容器に、上記エマルション（ａ）およびエマルション（ｂ）を、固形分重量比がエマルション（ａ）：エマルション（ｂ）＝５０：５となるように混合したものを５５０部、上水５０部、アジピン酸ジヒドラジド１部を入れ、均一になるように攪拌して、樹脂エマルション（Ｒ−１）を得た。
樹脂溶液（Ｒ−２）の製造
製造例１４
１リットルのステンレス容器に、固形分５５重量％のアクリルポリオール樹脂（ガラス転移温度５５℃、商品名「アクリディックＡ−３７０」、大日本インキ化学工業（株）製）５５０部、ミネラルスピリット５０部を入れ、均一に攪拌して、樹脂溶液（Ｒ−２）を得た。
遮熱性塗膜形成用上塗り塗料組成物の製造 Hereinafter, the present invention will be described more specifically with reference to production examples, examples and comparative examples.
In each example, “part” indicates “part by weight”. The average primary particle diameter of the pigment was observed and determined using an electron microscope (trade name “LUZEX AP”, manufactured by Nireco Corporation). The L ^* value based on the L ^* a ^* b ^* color system defined in JIS Z 8729 is determined using a colorimeter (trade name “Color Computer SM-7”, manufactured by Suga Test Instruments Co., Ltd.). It was measured.
Production and production example 1 of pigment paste
The following components for pigment paste were placed in a 1 liter stainless steel container, and stirred for 30 minutes with a stirrer to disperse to prepare an aqueous pigment paste (P-1).
Water 100 parts Ethylene glycol 40 parts Dispersion resin (Note 1) 20 parts Antifoam agent (Note 2) 20 parts Thickener (Note 3) 20 parts Clay (Note 4) 100 parts Titanium dioxide powder (Note 5) 120 Part Titanium dioxide powder (Note 6) 120 parts The above (Note 1) to (Note 6) indicate the following.
(Note 1) Dispersing resin: trade name “Nopcosper 44C”, manufactured by San Nopco, sodium polycarboxylate resin, solid content 43% by weight.
(Note 2) Antifoaming agent: Trade name “SN Deformer 364”, manufactured by San Nopco.
(Note 3) Thickener: Trade name “Fuji Chemi HEC KF100”, manufactured by Fuji Chemical Co., Ltd.
(Note 4) Clay: Trade name “POLYGROSS 90”; M.M. Huber, average particle size 5 μm, refractive index 1.30.
(Note 5) Titanium dioxide powder: trade name “TITANIIX JR-605”, manufactured by Teika Co., Ltd., refractive index 2.72, average primary particle size 250 nm.
(Note 6) Titanium dioxide powder: Trade name “TITANIIX JR-1000”, manufactured by Teika Co., Ltd., refractive index 2.72, average primary particle size 1,000 nm.
Production Example 2
In Production Example 1, aqueous pigment paste (P) was used in the same manner as in Production Example 1 except that 120 parts of titanium dioxide powder (Note 5) was not used and the amount of titanium dioxide powder (Note 6) used was 240 parts. -2).
Production Example 3
In Production Example 1, an aqueous pigment paste (P-3) was prepared in the same manner as in Production Example 1, except that 120 parts of zinc oxide powder (Note 7) was used instead of 120 parts of titanium dioxide powder (Note 6). did.
The above (Note 7) indicates the following.
(Note 7) Zinc oxide powder: Trade name “Zinc oxide 2 types”, Sakai Chemical Industry Co., Ltd., refractive index 2.00, average primary particle diameter 600 nm.
Production Example 4
In Production Example 1, aqueous pigment paste (P) was used in the same manner as in Production Example 1 except that 120 parts of titanium dioxide powder (Note 6) was not used and the amount of titanium dioxide powder (Note 5) used was 240 parts. -4) was created.
Production Example 5
The following blending components were put into a 1 liter stainless steel container, and stirred and dispersed with a stirrer for 30 minutes to prepare an organic solvent pigment paste (P-5).
Mineral spirit 100 parts Dispersing resin (Note 8) 40 parts Defoamer (Note 9) 20 parts Titanium dioxide powder (Note 6) 240 parts The above (Note 8) and (Note 9) indicate the following.
(Note 8) Resin for dispersion: trade name “BYK-109”, manufactured by BYK Chemie, hydroxyl group-containing carboxylic acid ester resin, solid content 100% by weight.
(Note 9) Antifoaming agent: trade name “BYK-066”, manufactured by Big Chemie.
Production Example 6
In Production Example 5, an organic solvent-based pigment paste (P-6) was used in the same manner as in Production Example 5 except that 240 parts of titanium dioxide powder (Note 10) was used instead of 240 parts of titanium dioxide powder (Note 6). It was created.
The above (Note 10) indicates the following.
(Note 10) Titanium dioxide powder: trade name “TITANIIX JR-805”, manufactured by Teika Co., Ltd., refractive index 2.72, average primary particle size 250 nm.
Production Example 7
In Production Example 5, an organic solvent-based pigment paste (P-7) was prepared in the same manner as in Production Example 5 except that 240 parts of titanium dioxide powder (Note 5) was used instead of 240 parts of titanium dioxide powder (Note 6). It was created.
Production Example 8
In Production Example 5, an organic solvent-based pigment paste (P-8) was prepared in the same manner as in Production Example 5 except that 240 parts of zinc oxide powder (Note 7) was used instead of 240 parts of titanium dioxide powder (Note 6). It was created.
Production example 9 of carbonyl group-containing acrylic copolymer emulsion (a)
In a flask, put 36 parts of deionized water and 0.36 part of an anionic surfactant (Note 11). After purging with nitrogen, warm to 80 ° C. and maintain 0.1% of the internal liquid at 80 ° C. After adding ammonium persulfate, a monomer emulsion having the following composition was added dropwise over 3 hours.
Monomer emulsion composition Deionized water 52.4 parts Diacetone acrylamide 10 parts Acrylic acid 0.5 parts Styrene 17.5 parts Methyl methacrylate 18 parts 2-Ethylhexyl acrylate 18 parts n-Butyl acrylate 36 parts Anionic surfactant ( Note 11) 9.6 parts ammonium persulfate 0.2 parts Over 30 minutes after the completion of dropping, a solution of 0.1 part ammonium persulfate in 1 part deionized water is added dropwise, and further 80 hours 2 hours. The emulsion (a) was obtained by keeping at 0 ° C.
The above (Note 11) indicates the following.
(Note 11) Anionic surfactant: trade name “Newcol 707SF”, manufactured by Nippon Emulsifier Co., Ltd., ammonium sulfate having a polyoxyethylene chain, solid content 30% by weight.
The obtained resin emulsion was applied to a glass plate (150 mm × 100 mm × 2 mm) using a doctor blade, dried and cured for 2 weeks at a temperature of 23 ° C. and a relative humidity of 50%, and then the coating film was peeled off. A free coating film having a dry film thickness of about 1 mm was obtained. It was 1.52 when the refractive index of this free coating film was measured using the Abbe refractometer as described in JISK0062.
Production and production example 10 of maleimide group-containing acrylic copolymer emulsion (b)
In a flask, 10 parts of a maleimide group-containing monomer represented by the following formula (4), 50 parts of n-butyl methacrylate, 25 parts of methyl methacrylate, 14 parts of n-butyl acrylate and 1 part of methacrylic acid are mixed, and the mixture is mixed. Add 100 parts of deionized water and 0.5 part of a radical polymerizable surfactant (trade name “AQUALON HS10”, manufactured by Daiichi Kogyo Seiyaku Co., Ltd., ammonium sulfate having a polymerizable unsaturated group and an oxyethylene group). A monomer emulsion was prepared using a rotating homomixer.
On the other hand, the inside of the flask containing 45 parts of deionized water and 0.5 part of a radical polymerizable surfactant (“AQUALON HS10”) was purged with nitrogen, and then heated to a temperature of 80 ° C., and the internal solution was brought to a temperature of 80 ° C. While maintaining, 1 part of ammonium persulfate and 2% by weight of the above monomer emulsion were added thereto, and the remaining monomer emulsion was added dropwise over 2 hours from 15 minutes after the addition, and then for 2 hours. Aged. After aging, the mixture was cooled, and 3 parts of 10% by weight ammonia water was added dropwise as a neutralizing agent to obtain a resin emulsion (b).
A free coating film was prepared from this emulsion in the same manner as in Production Example 9, and the refractive index was measured to be 1.52.

Production and production example 11 of fatty acid-modified acrylic resin (c)
In the flask, 100 parts of mineral spirits were charged, and the temperature was raised to 115 ° C. with stirring while venting nitrogen gas. Next, while maintaining the temperature at 115 ° C., 25 parts of styrene, 15 parts of n-butyl methacrylate, 20 parts of i-butyl methacrylate, 20 parts of 2-ethylhexyl acrylate, 20 parts of glycidyl methacrylate and 2,2′-azobisisobutyrate. A mixture of 1 part of nitrile was added dropwise over 4 hours. Next, after aging at 115 ° C. for 2 hours, after raising the temperature to 140 ° C., 30 parts of linseed oil fatty acid and 0.4 part of N, N-dimethylaminoethanol as a reaction catalyst were added and held at 160 ° C. for 5 hours. Fatty acid addition reaction was performed. 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, 45 parts of xylene was added and diluted to obtain a brown transparent and viscous fatty acid-modified copolymer solution having a nonvolatile content of 50% by weight. Next, the flask was cooled to 100 ° C., and the flask was equipped with a water separator. Silicon resin (polyalkylphenylsiloxane having a silanol group, trade name “SH-6018”, manufactured by Toray Dow Corning Silicone Co., Ltd.) 20 Part, 14 parts of mineral spirit, 6 parts of xylene and 0.20 part of tetra-n-butyl titanate as a reaction catalyst, heated to 165 ° C., and separated water in a reflux system for 5 hours. A brown transparent and viscous silicon-containing fatty acid-modified acrylic resin (c) having a nonvolatile content of about 50% by weight was obtained.
Production Example 12 of Acrylic Copolymer Emulsion (d)
In a flask, put 36 parts of deionized water and 0.36 part of an anionic surfactant (Note 11). After purging with nitrogen, warm to 80 ° C. and maintain 0.1% of the internal liquid at 80 ° C. After adding ammonium persulfate, a monomer emulsion having the following composition was added dropwise over 3 hours.
Monomer emulsion composition Deionized water 52.4 parts Acrylic acid 0.5 part Styrene 17.5 parts Methyl methacrylate 28 parts 2-Ethylhexyl acrylate 18 parts n-Butyl acrylate 36 parts Anionic surfactant (Note 11) 9. 6 parts Ammonium persulfate 0.2 part 30 minutes after the completion of dropping, a solution of 0.1 part ammonium persulfate dissolved in 1 part deionized water was added dropwise, and the emulsion was further maintained at 80 ° C. for 2 hours. (D) was obtained.
Production and production example 13 of resin emulsion (R-1)
550 parts of a mixture of the above emulsion (a) and emulsion (b) mixed in a 2 liter stainless steel container so that the solid content weight ratio is emulsion (a): emulsion (b) = 50: 5, 50 parts and 1 part of adipic acid dihydrazide were added and stirred uniformly to obtain a resin emulsion (R-1).
Production Production Example 14 of Resin Solution (R-2) 14
In a 1 liter stainless steel container, 550 parts of an acrylic polyol resin (glass transition temperature 55 ° C., trade name “Acrydic A-370”, manufactured by Dainippon Ink & Chemicals, Inc.) with a solid content of 55% by weight, 50 parts of mineral spirits And stirred uniformly to obtain a resin solution (R-2).
Manufacture of top coating composition for thermal barrier coating formation

270 parts of an aqueous pigment paste (P-1) is placed in a 1 liter stainless steel container, and further 600 parts of a resin emulsion (R-1), 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate 60 parts were added with stirring, and adjusted to pH 7-9 with aqueous ammonia to obtain an aqueous coating composition.
In this coating composition, the mixing ratio of titanium dioxide powder having an average primary particle diameter of 250 nm with respect to 100 parts by weight of the resin component was 20 parts, and the mixing ratio of titanium dioxide powder having an average primary particle diameter of 1,000 nm was 20 parts. It was.
Here, the resin component in the coating composition is the total amount of the resin solid content in the resin emulsion (R-1) and the resin solid content in the aqueous pigment paste (P-1).

In Example 1, it replaced with the water-based pigment paste (P-1), and except having mix | blended the same quantity of water-based pigment paste (P-2), it carried out similarly to Example 1, and obtained the water-based coating composition.
In this coating composition, the blending ratio of titanium dioxide powder having an average primary particle diameter of 1,000 nm with respect to 100 parts by weight of the resin component was 40 parts.
Here, the resin component in the coating composition is the total amount of the resin solid content in the resin emulsion (R-1) and the resin solid content in the aqueous pigment paste (P-2).

In Example 1, it replaces with resin emulsion (R-1), and it mix | blends similarly to Example 1 except mix | blending acrylic copolymer emulsion (d) so that it may become the same amount by solid content, Aqueous paint composition I got a thing.
In this coating composition, the mixing ratio of titanium dioxide powder having an average primary particle diameter of 250 nm with respect to 100 parts by weight of the resin component was 20 parts, and the mixing ratio of titanium dioxide powder having an average primary particle diameter of 1,000 nm was 20 parts. It was.

A two-component urethane curable organic solvent coating composition comprising a base resin and a curing agent was prepared by the following method.
280 parts of organic solvent-based pigment paste (P-5) is placed in a 1 liter stainless steel container, and 600 parts of the resin solution (R-2) obtained in Production Example 13 is added with stirring to contain an acrylic polyol resin. A base resin solution was obtained.
Separately, 50 parts of isocyanurate of hexamethylene diisocyanate (trade name “Duranate TSS-100”, manufactured by Asahi Kasei Co., Ltd.) and 10 parts of a low condensate of ethyl silicate (trade name “ES-48”, manufactured by Colcoat) Mixing was performed to obtain a curing agent. When used as a paint, 20 parts of the curing agent is blended with 100 parts of the solid content of the base resin solution.
The blending ratio of the titanium dioxide powder having an average primary particle diameter of 1,000 nm with respect to 100 parts by weight of the resin component in this paint was 50 parts.

280 parts of organic solvent pigment paste (P-5) is placed in a 1 liter stainless steel container, and further 600 parts of the fatty acid-modified acrylic resin (c) obtained in Production Example 11 is mixed and stirred to form a room temperature crosslinking type. An organic solvent-type coating composition was obtained.
The blending ratio of the titanium dioxide powder having an average primary particle diameter of 1,000 nm with respect to 100 parts by weight of the resin component in this paint was 50 parts.
Manufacture of dark top coating composition

The following blending components were put into a 1 liter stainless steel container, stirred for 30 minutes with a stirrer and dispersed, and then adjusted to pH 7 to 9 with aqueous ammonia to prepare an aqueous color coating composition (chocolate color). .
Water 100 parts Ethylene glycol 20 parts Pigment dispersing resin (Note 1) 10 parts Defoamer (Note 2) 10 parts Thickener (Note 3) 10 parts Clay (Note 4) 50 parts Red pigment paste (Note 12) 80 parts Green pigment paste (Note 13) 20 parts Titanium dioxide pigment (Note 6) 60 parts Resin emulsion (a) obtained in Production Example 9 500 parts Resin emulsion (b) obtained in Production Example 10 50 parts 2,2, 4-trimethyl-1,3-pentanediol monoisobutyrate 60 parts The above (Note 12) and (Note 13) indicate the following.
(Note 12) Red pigment paste: trade name “NS BROWN C522”, manufactured by Sanyo Dye Co., Ltd. Pigment: red iron oxide (content: 50% by weight).
(Note 13) Green pigment paste: trade name “NS GREEN 4711”, manufactured by Sanyo Dye Co., Ltd., pigment; phthalocyanine green (content 30% by weight).

表１において、ＪＲ−６０５、ＪＲ−１０００及びＪＲ−８０５は、平均１次粒子径２５０ｎｍの二酸化チタン粉末「ＴＩＴＡＮＮＩＸ ＪＲ−６０５」（商品名、テイカ（株）製）、平均１次粒子径１，０００ｎｍの二酸化チタン粉末「ＴＩＴＡＮＮＩＸ ＪＲ−１０００」（商品名、テイカ（株）製）及び平均１次粒子径２５０ｎｍの二酸化チタン粉末「ＴＩＴＡＮＮＩＸ ＪＲ−８０５」（商品名、テイカ（株）製）を、それぞれ示す。また、酸化亜鉛は、平均１次粒子径６００ｎｍの酸化亜鉛粉末（商品名「酸化亜鉛２種」、堺化学工業（株）製）を示す。
実施例８〜１４および比較例５〜８
スレート板（７０ｍｍ×１５０ｍｍ×５ｍｍ）に、実施例１〜７及び比較例１〜４で得られた各塗料組成物を、乾燥膜厚が１，０００μｍとなるようにドクターブレードを用いて塗装し、２３℃（相対湿度５０％）にて１４日間乾燥させて、試験塗板を得た。
また、スレート板に代えて、ガラス板（１５０ｍｍ×１００ｍｍ×２ｍｍ）を用いた他は同様に、塗装及び乾燥し、次いで乾燥塗膜を剥離して遊離塗膜を得た。
上記で得られた各試験塗板について、光沢、下地隠蔽性及びＬ^＊値を調べた。また、上記で得られた各遊離塗膜について、遮熱効果を調べた。各試験方法は、以下の通りである。
光沢
各試験塗板の鏡面光沢度（６０°グロス）を測定した。大きいほど光沢が高いことを意味する。
下地隠蔽性
各試験塗板を目視で観察し、次の基準で評価した。Ａは下地が観察できず隠蔽性が良好であることを、Ｂは下地が観察でき、隠蔽性が不良であることを、それぞれ示す。
Ｌ ^＊ 値
各試験塗板の塗膜について、測色計（商品名「カラーコンピュータＳＭ−７」、スガ試験機（株）製）を用いてＪＩＳ Ｚ ８７２９に規定されるＬ^＊ａ^＊ｂ^＊表色系に基づくＬ^＊値を測定した。
遮熱効果
上記遊離塗膜の遮熱効果を、図１に示した温度測定装置を用いて、調べた。図１は、該装置の概略を示した断面図である。図１において符号１は光源を、２は試験用の遊離塗膜を、３は発泡スチロール製の箱を、４〜６は温度センサーとして用いられる熱電対温度計を、それぞれ示す。
光源１としては、赤外線を含む光を発する白熱電球（商品名「レフランプ」、１００Ｗ、東芝（株）製）を用いた。乾燥膜厚１，０００μｍの遊離塗膜（５０ｍｍ×７０ｍｍ）を、箱３の上面に設けられた遊離塗膜と同じ大きさの穴に、設置した。光源１と遊離塗膜２の距離は１５ｃｍとした。熱電対温度計を、遊離塗膜２の表面と裏面及び箱３の内部に夫々設置した。
光源１の電源を入れ、遊離塗膜表面に赤外線を含む光を照射しながら、塗膜の表面、裏面及び箱内部の各温度を測定し、各温度が一定値に収束したときの各温度を調べた。箱内部温度が低いほど、遮熱効果が高いことを意味する。
上記試験結果を、表２に示す。

実施例１５および比較例９
スレート板（７０ｍｍ×１５０ｍｍ×５ｍｍ）に、アクリル樹脂エマルション系下塗り塗料組成物（商品名「アレスホルダーＧＩＩ」、関西ペイント（株）製、顔料体積濃度６２％、２０℃での破断伸び率１２０％）を、乾燥膜厚が１ｍｍとなるようにドクターブレードを用いて塗装し、室温（２３℃）で１６時間乾燥させた後、該塗面上に実施例１又は比較例１で得られた塗料組成物を乾燥膜厚が５０μｍとなるようにドクターブレードを用いて塗装し、室温（２３℃）で１４日間乾燥させ、試験塗板とした。In Example 1, it replaced with the water-based pigment paste (P-1), and except having mix | blended the same quantity of water-based pigment paste (P-3), it carried out similarly to Example 1, and obtained the water-based coating composition.
Comparative Example 1
In Example 1, it replaced with the water-based pigment paste (P-1), and except having mix | blended the same amount of water-based pigment paste (P-4), it carried out similarly to Example 1, and obtained the water-based coating composition.
Comparative Example 2
In Example 4, instead of the organic solvent-based pigment paste (P-5), an acrylic polyol resin is contained in the same manner as in Example 4 except that the same amount of the organic solvent-based pigment paste (P-6) is blended. A base resin solution was obtained. A two-pack urethane curable organic solvent coating composition comprising this base resin solution and the curing agent described in Example 4 was obtained.
Comparative Example 3
In Example 5, in place of the organic solvent-based pigment paste (P-5), the same amount of the organic solvent-based pigment paste (P-7) is blended in the same manner as in Example 5 except that it is a room temperature crosslinking type organic. A solvent-type coating composition was obtained.
Comparative Example 4
280 parts of organic solvent pigment paste (P-8) is put into a 1 liter stainless steel container, and further, a vinyl chloride resin (trade name “45% Kanebirak LE-Y”, manufactured by Kaneka Chemical Co., Ltd., refractive index of coating film) 1.75) 600 parts were mixed and stirred to obtain a room temperature drying type organic solvent type coating composition.
About each coating composition obtained in the said Examples 1-7 and Comparative Examples 1-4, the refractive index of the resin film, the pigment volume concentration of the coating film, and the elongation at break were measured according to the following test method.
Refractive index of resin film A resin composition having a composition obtained by removing the pigment component from each coating composition was prepared, and this was applied to a glass plate (150 mm × 100 mm × 2 mm) using a doctor blade, at a temperature of 23 ° C. and a relative humidity. After drying and curing for 2 weeks under the condition of 50%, the coating film was peeled off to obtain a free coating film having a dry film thickness of about 1 mm. The refractive index of the free coating film was measured using an Abbe refractometer described in JIS K0062.
Pigment volume concentration (PVC)
Each coating composition was applied to a glass plate (150 mm × 100 mm × 2 mm) using a doctor blade, dried and cured at a temperature of 23 ° C. and a relative humidity of 50% for 2 weeks, and then the coating film was peeled off. A free coating film having a dry film thickness of about 1 mm was obtained. A cross-sectional photograph of this free coating film was taken with a scanning electron microscope (trade name “JSM-5310LV”, manufactured by JEOL Ltd.) to obtain an SEM photograph. In the SEM photograph of the coating film cross section, a continuous phase based on the resin component and a dispersed phase based on the pigment component were observed. The free coating film was analyzed with wavelength-type EPMA (trade name “JXA-8100”, manufactured by JEOL Ltd.), and among the dispersed phases observed in the SEM photograph, the dispersed phases caused by titanium dioxide and zinc oxide were analyzed. Identified. About the disperse phase resulting from the identified titanium dioxide, the major axis and the minor axis are converted from the magnification in the SEM photograph, and the disperse phase having an average of 500 to 2,000 nm is the average primary particle diameter of 1,000 nm. Titanium was used, and the dispersed phase of less than 400 nm was titanium dioxide having an average primary particle size of 250 nm. Moreover, about the disperse phase resulting from the identified zinc oxide, the disperse phase having an average major axis and minor axis of 500 to 2,000 nm was defined as zinc oxide having an average primary particle diameter of 600 nm.
Among the dispersed phases observed in the SEM photograph, the dispersed phase attributed to each white pigment is specified by the above criteria, and the volume ratio of the pigment is calculated by calculating the ratio of the total area of the dispersed phase to the coating cross-sectional area. (%) Was calculated.
Elongation at break (%)
Each coating composition was applied to release paper (200 mm x 200 mm) using a doctor blade, dried and cured for 2 weeks at a temperature of 23 ° C and a relative humidity of 50%, and then the coating film was peeled off to form a dry film. A free coating film having a thickness of about 1 mm was obtained. The elongation at break of the free coating film was measured using a tensile tester (trade name “Autograph AG2000B type”, manufactured by Shimadzu Corporation) at a temperature of 20 ° C. and a tensile speed of 200 mm / min.
The test results are shown in Table 1.

In Table 1, JR-605, JR-1000 and JR-805 are titanium dioxide powder “TITANIIX JR-605” (trade name, manufactured by Teika Co., Ltd.) having an average primary particle diameter of 250 nm, and an average primary particle diameter of 1 2,000 nm titanium dioxide powder “TITANIIX JR-1000” (trade name, manufactured by Teika) and titanium dioxide powder “TITANIIX JR-805” (trade name, manufactured by Teika) with an average primary particle size of 250 nm. , Respectively. Zinc oxide indicates zinc oxide powder having an average primary particle diameter of 600 nm (trade name “Zinc Oxide 2”, manufactured by Sakai Chemical Industry Co., Ltd.).
Examples 8-14 and Comparative Examples 5-8
Each paint composition obtained in Examples 1 to 7 and Comparative Examples 1 to 4 was applied to a slate plate (70 mm × 150 mm × 5 mm) using a doctor blade so that the dry film thickness was 1,000 μm. , And dried at 23 ° C. (relative humidity 50%) for 14 days to obtain a test coated plate.
Moreover, it replaced with the slate plate and applied and dried similarly except having used the glass plate (150 mm x 100 mm x 2 mm), and then peeled off the dried coating film, and obtained the free coating film.
About each test coating board obtained above, glossiness, base concealment property, and L ^* value were investigated. Moreover, the heat shielding effect was investigated about each free coating film obtained above. Each test method is as follows.
Gloss The specular gloss (60 ° gloss) of each test coating plate was measured. Larger means higher gloss.
The base concealing properties each test coated plate was visually observed and evaluated according to the following criteria. A indicates that the background cannot be observed and the concealability is good, and B indicates that the background can be observed and the concealability is poor.
L ^* value L ^* a ^* b ^* table defined in JIS Z 8729 using a colorimeter (trade name “Color Computer SM-7”, manufactured by Suga Test Instruments Co., Ltd.) L ^* values based on the color system were measured.
Thermal barrier effect The thermal barrier effect of the above-mentioned free coating film was examined using the temperature measuring device shown in FIG. FIG. 1 is a sectional view schematically showing the apparatus. In FIG. 1, reference numeral 1 denotes a light source, 2 denotes a free coating film for testing, 3 denotes a box made of expanded polystyrene, and 4 to 6 denote thermocouple thermometers used as temperature sensors.
As the light source 1, an incandescent bulb (trade name “Leff Lamp”, 100 W, manufactured by Toshiba Corporation) that emits light including infrared rays was used. A free coating film (50 mm × 70 mm) having a dry film thickness of 1,000 μm was placed in a hole having the same size as the free coating film provided on the upper surface of the box 3. The distance between the light source 1 and the free coating film 2 was 15 cm. Thermocouple thermometers were installed on the front and back surfaces of the free coating film 2 and inside the box 3, respectively.
Turn on the power of the light source 1 and measure the temperature on the surface, back surface, and inside the box while irradiating the surface of the free paint film with infrared rays. Examined. The lower the box internal temperature, the higher the heat shielding effect.
The test results are shown in Table 2.

Example 15 and Comparative Example 9
A slate plate (70 mm x 150 mm x 5 mm) with an acrylic resin emulsion base coating composition (trade name “Ares Holder GII”, manufactured by Kansai Paint Co., Ltd., pigment volume concentration 62%, elongation at break at 20 ° C. 120% ) Was applied using a doctor blade so that the dry film thickness was 1 mm, dried at room temperature (23 ° C.) for 16 hours, and then the paint obtained in Example 1 or Comparative Example 1 on the coated surface. The composition was coated with a doctor blade so that the dry film thickness was 50 μm, and dried at room temperature (23 ° C.) for 14 days to obtain a test coated plate.

Examples 16-17

表３において、ホルダーＧＩＩは、アクリル樹脂エマルション系下塗り塗料組成物（商品名「アレスホルダーＧＩＩ」、関西ペイント（株）製）を示す。
顔料ペーストの製造
製造例１５
１リットルのステレンス容器に、下記に示す顔料ペースト用の配合成分を入れ、攪拌機にて３０分間攪拌し分散して水性顔料ペースト（Ｐ−９）を作成した。
上水 １００部
エチレングリコール ４０部
分散用樹脂（注１） ２０部
消泡剤（注２） ２０部
増粘剤（注３） ２０部
二酸化チタン粉末（注５） １２０部
二酸化チタン粉末（注６） １２０部
製造例１６
１リットルのステレンス容器に、下記に示す顔料ペースト用の配合成分を入れ、攪拌機にて３０分間攪拌し分散して水性顔料ペースト（Ｐ−１０）を作成した。
上水 １００部
エチレングリコール ４０部
分散用樹脂（注１） ２０部
消泡剤（注２） ２０部
増粘剤（注３） ２０部
二酸化チタン粉末（注５） １１０部
二酸化チタン粉末（注６） １１０部
赤色顔料ペースト（注１２） １０部
緑色顔料ペースト（注１３） １０部
製造例１７
１リットルのステレンス容器に、下記に示す顔料ペースト用の配合成分を入れ、攪拌機にて３０分間攪拌し分散して水性顔料ペースト（Ｐ−１１）を作成した。
上水 １００部
エチレングリコール ４０部
消泡剤（注２） ２０部
増粘剤（注３） ２０部
赤色顔料ペースト（注１２） ４０部
緑色顔料ペースト（注１３） ４０部
製造例１８
１リットルのステレンス容器に、下記に示す顔料ペースト用の配合成分を入れ、攪拌機にて３０分間攪拌し分散して水性顔料ペースト（Ｐ−１２）を作成した。
上水 １００部
エチレングリコール ４０部
分散用樹脂（注１） ２０部
消泡剤（注２） ２０部
増粘剤（注３） ２０部
二酸化チタン粉末（注５） １２０部
二酸化チタン粉末（注６） １２０部
ペリレン系黒色顔料（注１４） ５部
上記（注１４）は、下記のものを示す。
（注１４）ペリレン系黒色顔料：商品名「ＰＡＬＩＯＧＥＮ ＢＬＡＣＫ Ｓ ００８４」、ＢＡＳＦ社製。
製造例１９
１リットルのステレンス容器に、下記に示す顔料ペースト用の配合成分を入れ、攪拌機にて３０分間攪拌し分散して水性顔料ペースト（Ｐ−１３）を作成した。
上水 １００部
エチレングリコール ４０部
消泡剤（注２） ２０部
増粘剤（注３） ２０部
カーボンブラック顔料ペースト（注１５） ２０部
上記（注１５）は、下記のものを示す。
（注１５）カーボンブラック顔料ペースト：商品名「ＮＳブラックＣ−６２８」、山陽色素社製。
製造例２０
１リットルのステレンス容器に、下記に示す顔料ペースト用の配合成分を入れ、攪拌機にて３０分間攪拌し分散して水性顔料ペースト（Ｐ−１４）を作成した。
上水 １００部
ヒドロキシエチルセルロース（増粘剤） ０．５部
分散用樹脂（注１６） ６．６部
ペリレン系黒色顔料（注１４） ３３．３部
上記（注１６）は、下記のものを示す。
（注１６）分散用樹脂：商品名「ＢＹＫ−１９０」、ビッグ・ケミー社製、ポリカルボン酸系樹脂、固形分４０重量％。
遮熱性塗膜形成用下塗り塗料組成物の製造 The paint composition obtained in Example 2 was applied to a slate plate (70 mm × 150 mm × 5 mm) using a doctor blade so that the dry film thickness was 150 μm, and dried at room temperature (23 ° C.) for 16 hours. It was. Next, the coating composition obtained in Example 1 or Comparative Example 1 was applied on the coated surface so that the dry film thickness was 50 μm and dried at room temperature (23 ° C.) for 14 days to obtain a test coated plate. .
About each test coating plate obtained by the said Examples 15-17 and the comparative example 9, glossiness, base | substrate concealment property, and L ^* value were investigated with the said method. Moreover, about each free coating film obtained by using a glass plate instead of a slate plate, the heat-shielding effect was investigated by the said method.
The test results are shown in Table 3.

In Table 3, the holder GII indicates an acrylic resin emulsion-based undercoat coating composition (trade name “Ares Holder GII”, manufactured by Kansai Paint Co., Ltd.).
Production and production example 15 of pigment paste
The components for pigment paste shown below were placed in a 1 liter stainless steel container, and stirred and dispersed for 30 minutes with a stirrer to prepare an aqueous pigment paste (P-9).
Water 100 parts Ethylene glycol 40 parts Dispersion resin (Note 1) 20 parts Antifoam agent (Note 2) 20 parts Thickener (Note 3) 20 parts Titanium dioxide powder (Note 5) 120 parts Titanium dioxide powder (Note 6) 120 parts Production Example 16
The following components for pigment paste were placed in a 1 liter stainless steel container and stirred and dispersed for 30 minutes with a stirrer to prepare an aqueous pigment paste (P-10).
Water 100 parts Ethylene glycol 40 parts Dispersing resin (Note 1) 20 parts Antifoaming agent (Note 2) 20 parts Thickener (Note 3) 20 parts Titanium dioxide powder (Note 5) 110 parts Titanium dioxide powder (Note 6) 110 parts Red pigment paste (Note 12) 10 parts Green pigment paste (Note 13) 10 parts Production Example 17
The following components for pigment paste were placed in a 1 liter stainless steel container and stirred and dispersed with a stirrer for 30 minutes to prepare an aqueous pigment paste (P-11).
Water 100 parts Ethylene glycol 40 parts Antifoaming agent (Note 2) 20 parts Thickener (Note 3) 20 parts Red pigment paste (Note 12) 40 parts Green pigment paste (Note 13) 40 parts Production Example 18
The following components for pigment paste were placed in a 1 liter stainless steel container and stirred and dispersed with a stirrer for 30 minutes to prepare an aqueous pigment paste (P-12).
Water 100 parts Ethylene glycol 40 parts Dispersion resin (Note 1) 20 parts Antifoam agent (Note 2) 20 parts Thickener (Note 3) 20 parts Titanium dioxide powder (Note 5) 120 parts Titanium dioxide powder (Note 6) ) 120 parts Perylene-based black pigment (Note 14) 5 parts The above (Note 14) indicates the following.
(Note 14) Perylene-based black pigment: trade name “PALIOGEN BLACK S 0084”, manufactured by BASF Corporation.
Production Example 19
The following components for pigment paste were placed in a 1 liter stainless steel container and stirred and dispersed with a stirrer for 30 minutes to prepare an aqueous pigment paste (P-13).
Water 100 parts Ethylene glycol 40 parts Antifoaming agent (Note 2) 20 parts Thickener (Note 3) 20 parts Carbon black pigment paste (Note 15) 20 parts The above (Note 15) indicates the following.
(Note 15) Carbon black pigment paste: trade name “NS Black C-628”, manufactured by Sanyo Dye
Production Example 20
The following components for pigment paste were placed in a 1 liter stainless steel container, and stirred for 30 minutes with a stirrer to disperse to prepare an aqueous pigment paste (P-14).
Water 100 parts Hydroxyethyl cellulose (thickener) 0.5 parts Dispersion resin (Note 16) 6.6 parts Perylene black pigment (Note 14) 33.3 parts The above (Note 16) indicates the following: .
(Note 16) Resin for dispersion: trade name “BYK-190”, manufactured by Big Chemie, polycarboxylic acid resin, solid content 40% by weight.
Manufacture of undercoating composition for thermal barrier coating formation

表４における樹脂エマルションＲ−３、Ｒ−４及びＲ−５は、以下のものを示す。
Ｒ−３：シリコーン樹脂エマルション、商品名「３８％サンモールＥＷ１０２」、サンノプコ社製、被膜の屈折率１．５５。
Ｒ−４：アクリル樹脂エマルション、商品名「５４％ＭＫ−２５０」、大日本インキ化学工業（株）製、被膜の屈折率１．５５。
Ｒ−５：塩化ビニル樹脂エマルション、商品名「４５％モビニール」、クラリアントポリマー（株）製、被膜の屈折率１．７５。
製造例２１
１リットルのステレンス容器に、下記配合成分を、攪拌機にて３０分間攪拌混合することにより、黒色水性上塗り塗料組成物を得た。
水性顔料ペースト（Ｐ−１４） ２６５部
製造例９で得た樹脂エマルション（ａ） ２００部
２，２，４−トリメチル−１，３−ペン
タンジオール モノイソブチレート ２０部
増粘剤（注１７） ５部
上水 ５０部
実施例２３〜３０及び比較例１３〜１５
スレート板（１００ｍｍ×１５０ｍｍ×４ｍｍ）に、表５の組み合わせにて各下塗り塗料組成物及び上塗り塗料組成物をドクターブレードを用いて塗装し、試験塗板を作成し、各試験に供した。下塗り塗料組成物は乾燥膜厚が１５０μｍに、上塗り塗料組成物は乾燥膜厚が６０μｍとなるように塗装し、乾燥条件は共に温度２３℃、相対湿度５０％にて１４日間である。
上記実施例２３〜３０及び比較例１３〜１５で得られた各試験塗板について、前記方法により、光沢、下地隠蔽性及びＬ^＊値を調べた。
また、スレート板に代えてガラス板を用いて得られた各遊離塗膜について、前記方法と同様にして、遮熱効果を調べた。更に、各遊離塗膜について、赤外線反射率を、下記方法により、調べた。
赤外線反射率
乾燥した遊離塗膜について、分光反射率測定機（商品名「ＵＶ−３１００ＰＣ」、島津製作所（株）製）を使用して、波長７８０ｎｍ〜２，１００ｎｍの近赤外線領域における分光反射率を測定し、次いでＪＩＳ Ａ ５７５９に定義される日射反射率を算出し、その結果を赤外線反射率（％）とした。
上記試験結果を、表５に併記する。

表５における上塗り塗料Ｔ−１、Ｔ−２及びＴ−３は、以下のものを示す。
Ｔ−１：商品名「アレスアクアグロス 白」、関西ペイント（株）製、カルボニル基含有アクリル樹脂エマルション塗料、樹脂成分１００部に対して平均粒子径２２０ｎｍの二酸化チタン顔料５０部含有。
Ｔ−２：商品名「アレスアクアヤネシリコン グレー」、関西ペイント（株）製、カルボニル基含有アクリル樹脂エマルション塗料、樹脂成分１００部に対して平均粒子径２２０ｎｍの二酸化チタン顔料５０部及びカーボンブラック０．８部含有。
Ｔ−３：商品名「アレスアクアヤネシリコン クリーム」、関西ペイント（株）製、カルボニル基含有アクリル樹脂エマルション塗料、樹脂成分１００部に対して平均粒子径２２０ｎｍの二酸化チタン顔料５０部及び黄色酸化鉄２部含有。An aqueous undercoat coating composition was obtained by stirring and mixing the following blending components in a 1 liter stainless steel container with a stirrer for 30 minutes.
Aqueous pigment paste (P-10) 350 parts Resin emulsion obtained in Production Example 9 (a) 200 parts 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate 20 parts Thickener (Note 17) 5 parts Water 50 parts The above (Note 17) indicates the following.
(Note 17) Thickener: Trade name “DK thickener SCT-275”, manufactured by San Nopco.
Examples 19-22 and Comparative Examples 10-12
In Example 18, each undercoat paint composition was obtained with the same composition as in Example 18 except that the pigment paste and the resin emulsion were combined as shown in Table 4 below.
Table 4 also shows the L ^* value of the coating film formed from each undercoat coating composition. The L ^* value is the same as described above after coating each coating composition on a glass plate with a doctor blade so that the dry film thickness is 150 μm, and drying for 2 days at a temperature of 23 ° C. and a relative humidity of 65%. Measurement was performed using a colorimeter.

Resin emulsions R-3, R-4 and R-5 in Table 4 show the following.
R-3: Silicone resin emulsion, trade name “38% Sanmor EW102”, manufactured by San Nopco, refractive index of coating film 1.55.
R-4: Acrylic resin emulsion, trade name “54% MK-250”, manufactured by Dainippon Ink & Chemicals, Inc., refractive index of coating film: 1.55.
R-5: Vinyl chloride resin emulsion, trade name “45% Movinyl”, manufactured by Clariant Polymer Co., Ltd., refractive index of coating film 1.75.
Production Example 21
A black aqueous top coating composition was obtained by stirring and mixing the following ingredients in a 1 liter stainless steel container with a stirrer for 30 minutes.
Aqueous pigment paste (P-14) 265 parts Resin emulsion (a) obtained in Production Example 9 200 parts 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate 20 parts Thickener (Note 17) 5 parts clean water 50 parts Examples 23-30 and Comparative Examples 13-15
Each undercoat paint composition and topcoat paint composition were applied to a slate plate (100 mm × 150 mm × 4 mm) with the combination shown in Table 5 using a doctor blade to prepare test coat plates, which were subjected to each test. The undercoat paint composition was applied so that the dry film thickness was 150 μm, and the topcoat composition was applied so that the dry film thickness was 60 μm, and the drying conditions were both at a temperature of 23 ° C. and a relative humidity of 50% for 14 days.
About each test coating plate obtained by the said Examples 23-30 and Comparative Examples 13-15, glossiness, base | substrate concealing property, and L ^* value were investigated by the said method.
Moreover, about each free coating film obtained by using a glass plate instead of a slate plate, the heat-shielding effect was investigated like the said method. Furthermore, about each free coating film, the infrared reflectance was investigated by the following method.
Infrared reflectivity For the dried free coating film, using a spectral reflectometer (trade name “UV-3100PC”, manufactured by Shimadzu Corporation), the spectral reflectivity in the near infrared region of wavelength 780 nm to 2,100 nm. Then, the solar reflectance defined in JIS A 5759 was calculated, and the result was taken as the infrared reflectance (%).
The test results are also shown in Table 5.

Top coating materials T-1, T-2 and T-3 in Table 5 are as follows.
T-1: Trade name “Ares Aqua Gloss White”, manufactured by Kansai Paint Co., Ltd., carbonyl group-containing acrylic resin emulsion paint, containing 50 parts of titanium dioxide pigment having an average particle diameter of 220 nm with respect to 100 parts of the resin component.
T-2: Trade name “Ares Aqua Yane Silicon Gray”, manufactured by Kansai Paint Co., Ltd., carbonyl group-containing acrylic resin emulsion paint, 50 parts of titanium dioxide pigment having an average particle diameter of 220 nm with respect to 100 parts of resin component, and carbon black 0 Contains 8 parts.
T-3: Trade name “Ares Aqua Yane Silicon Cream”, manufactured by Kansai Paint Co., Ltd., carbonyl group-containing acrylic resin emulsion paint, 50 parts of titanium dioxide pigment having an average particle size of 220 nm and 100 parts of resin component and yellow iron oxide Contains 2 parts.

Claims (21)

(A) a resin component that forms a film having a refractive index of 1.30 to 1.60, and (B) an average primary particle diameter in the range of 500 to 2,000 nm and a refractive index of 1.80. A coating composition for forming a heat-shielding film containing a white pigment in the range of ˜3.00. The coating composition according to claim 1, wherein the resin component (A) contains a crosslinked acrylic resin or a non-crosslinked acrylic resin. The coating composition according to claim 1, wherein the resin component (A) contains a carbonyl group-containing acrylic copolymer and a hydrazine derivative. The coating composition according to claim 1, wherein the resin component (A) contains a maleimide group-containing acrylic copolymer. The coating composition according to claim 1, wherein the resin component (A) contains an unsaturated fatty acid-modified acrylic resin. The coating composition according to claim 1, wherein the white pigment (B) is titanium dioxide and / or zinc oxide. The coating composition according to claim 1, wherein the blending ratio of the white pigment (B) is 10 to 140 parts by weight with respect to 100 parts by weight of the resin component (A). Furthermore, the coating composition of Claim 1 containing the white pigment (C) whose average primary particle diameter is less than 400 nm. The coating composition according to claim 8, wherein the white pigment (C) is titanium dioxide and / or zinc oxide. The coating composition according to claim 8, wherein the blending ratio of the white pigment (C) is 10 to 140 parts by weight with respect to 100 parts by weight of the resin component (A). The coating composition according to claim 8, wherein the weight ratio of the white pigment (B) and the white pigment (C) is in the range of 10/90 to 90/10. Furthermore, the coating composition of Claim 1 containing a coloring pigment (D). The coating composition according to claim 12, comprising a plurality of chromatic pigments having a complementary color relationship as the color pigment (D). A top coating composition, which is the coating composition for forming a heat-shielding film according to claim 1. Furthermore, the coloring paint (D) is contained, The coating film of the brightness (L ^* value) 20-70 based on L ^* a ^* b ^* colorimetric system prescribed | regulated to JISZ8729 can be formed. Topcoat paint composition. An undercoat paint composition, which is the paint composition for forming a heat-shielding film according to claim 1. The undercoat paint composition according to claim 16, which can form a coating film having a lightness (L ^* value) of 70 to 98 based on the L ^* a ^* b ^* color system defined in JIS Z 8729. The coating method which coats the top coat composition of Claim 14 to a to-be-coated article by a single layer. The coating method which coats the top-coat paint composition of Claim 14 on this coating surface after coating a base-coat paint composition to a to-be-coated article. A coating method in which an undercoat paint composition according to claim 16 is applied to an article to be coated, and then a topcoat composition is applied onto the coated surface. The coating method according to claim 20, wherein the top coating composition is a coating composition containing a perylene pigment.

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