JP3605940B2 - Irregular pattern-forming powder coating, method for producing the same, and coated object - Google Patents

Description

【００３２】
上記により形成される塗膜は樹脂ビーズにより均一かつ緻密で微細な丸みを帯びた突起状の模様が形成されるため、ソフトで意匠性の高いサテン調の凹凸模様が得られる。そして（Ａ）成分の粉末塗料成分と（Ｂ）成分の樹脂ビーズが溶着により一体化していることにより、化学性能、物理性能、特に加工性および耐食性に優れた塗膜が得られる。凹凸模様の突起が丸みを帯びているかどうかは肉眼により観察可能であるが、拡大三次元断面図を作図することにより、視覚化することができる。
【００３３】
（Ｂ）成分の樹脂ビーズの代りに破砕状ないし不定形の樹脂粒状物を用いると、角ばった突起を有する塗膜が形成され、冷たい感じで、肌ざわりの悪い塗膜が形成され、角ばった部分から塗膜が剥離していくため、化学性能、物理性能なども劣る塗膜が得られる。
【００３４】
【発明の実施の形態】
以下、本発明の実施の形態を図面により説明する。
図１は（Ａ）成分の粉体塗料成分と（Ｂ）成分の樹脂ビーズからなる粉体塗料を塗布して凹凸塗膜を形成した塗装物を拡大して示すもので、（ａ）は斜視図、（ｂ）は断面図である。
【００３５】
図１において塗装物１は被塗装物２の表面に凹凸塗膜３が形成されている。この凹凸塗膜３は（Ａ）成分によって形成される塗膜４中に、（Ｂ）成分の樹脂ビーズ５が埋設されている。樹脂ビーズ５が存在しない部分が凹部６として形成され、樹脂ビーズ５が突出する部分が凸部７として形成されている。
【００３６】
この凹凸塗膜３は凸部７は球形の樹脂ビーズ５が突出し、かつ塗膜４が裾野状に連なるため、丸みを帯びた凸部７が形成され、ソフトで意匠性の高いサテン調の凹凸塗膜が得られる。
【００３７】
図２（ａ）は比較例として図１の樹脂ビーズ５の代りに破砕状の樹脂粒状物８を用いた塗装物を拡大して示す斜視図、（ｂ）はその断面図である。図２では凸部７は破砕状の樹脂粒状物８により形成されるため、角ばった突起となり、ソフトな凹凸模様は得られず、冷たい感じで肌ざわりの悪い塗膜が得られる。
【００３８】
【実施例】
次に、本発明を実施例によりさらに具体的に説明するが本発明はこれらの実施例によって何ら制限されるものではない。
【００３９】
各例中、塗膜性能等の物理性能は次のようにして求めた。
（１）鏡面光沢度
ＪＩＳ Ｋ−５４００（１９９０）７．６に準じて入射角と受光角が６０度の時の値を示した。
（２）鉛筆硬度
ＪＩＳ Ｋ−５４００（１９９０）８．４．２手かき法に準じて行った。
【００４０】
（３）エリクセン値
ＪＩＳ Ｋ−５４００（１９９０）８．２．２破断距離法に準じて行った。
（４）耐衝撃性
ＪＩＳ Ｋ−５４００（１９９０）８．３．２デュポン式に準じて行った。
（５）耐屈曲性
ＪＩＳ Ｋ−５４００（１９９０）８．１に準じて行った。
【００４１】
（６）加工性試験
試験片に素材片を挟み、万力を用いて１８０度折曲試験を行う。塗膜屈曲面におけるワレ等の塗膜欠陥を生じない素材片の数を示す。この場合、例えば２枚素材片を挟んだ際の合格値を２Ｔと表現した。
【００４２】
（７）耐塩水噴霧性
ＪＩＳ Ｋ−５４００（１９９０）９．１に準じて、塗膜表面にクロスカットを行った後３００時間連続で試験を行った。剥離試験はカット面上でテープ剥離を行い、カット中心線から剥離した幅の最大値を示した。
【００４３】
（８）表面状態
肉眼観察により次の基準で判定した。
普通：凸部が独立した突起状模様を形成している状態。
やや緻密：部分的に凸部の重複により突起状模様を形成している状態。
かなり緻密：大部分の凸部が重複し合うことにより突起状模様を形成している状態。
【００４４】
（９）表面粗度測定
ＪＩＳ Ｂ−０６０１（１９９４）表面粗さ一定義および表示に準じて表面粗さとうねりのパラメータを測定し、模様調の範囲を数値表現した。
［振幅に関するパラメータ］
Ｒａ：中心線平均粗さ（μｍ），Ｒｚ：十点平均粗さ（μｍ）
［波長に関するパラメータ］
Ｓｍ：凹凸の平均間隔（ｍｍ），Ｓ：局部的山頂の平均間隔（ｍｍ）
【００４５】
（１０）三次元断面図
三次元断面図は、三次元表面粗さ形状測定装置（商品名：（株）東京精密製品、サーフコム Ｅ−ＲＣ−ＸＹ３Ｂ）を用いて、傾斜補正されていない塗膜表面の断面曲線を縦倍率は１００倍、横倍率、ならびに前後倍率は５０倍、ピッチは２０μｍで測定することにより作成した。
【００４６】
（１１）模様調の評価
肉眼観察、三次元断面図および表面粗度測定結果から次の基準により総合判定した。
良好：均一かつ緻密で微細な丸みを帯びた突起状の模様を有する意匠性塗膜が形成されており、しかも突起状の模様に起因するパラメータが前記表１の好ましい範囲内にあること。
不良：上記以外。
【００４７】
実施例１〜３
表２に示した実施例１〜３の構成成分を、ドライブレンダー（商品名：ヘンシェルミキサー、三井三池化工機株式会社製）により約１分間均一に混合し、次に８０〜１００℃の温度条件で押出混練機（商品名：ブスコニーダーＰＲ−４６，ブス社製）を用いて溶融混練を行い、冷却後ハンマー式衝撃粉砕機で微粉砕したのち８０メッシュの金網で分級することにより粉体塗料を製造した。得られた粉体塗料は、表３に示す塗装平均膜厚となるように−８０ｋｖ荷電で静電吹付法により所定の板厚の被塗物に塗装を行った。次いで表３に示した焼付条件において加熱硬化させた後、塗膜外観および塗膜物性について評価を行った。結果を表３および図３〜５に示す。
【００４８】
【表２】

【００４９】
表２の注
１）商品名：ＤＳＭ Ｒｅｓｉｎｓ社製品、ポリエステル樹脂、酸価３５ｍｇＫＯＨ／ｇ。
２）商品名：大日本インキ化学工業（株）製品、ポリエステル樹脂、水酸基価３０ｍｇＫＯＨ／ｇ。
３）商品名：ＳｈｅｌｌＣｈｅｍｉｃａｌｓ社製品、エポキシ樹脂、エポキシ当量６５０ｇ／Ｅｑ。
４）商品名；ｈｕｅｌｓ社製品、アダクト体イソシアネート硬化剤、イソシアネート当量２８０ｇ／Ｅｑ。
５）商品名：Ｍｏｎｓａｎｔ社製品、レベリング剤。
６）商品名：Ｅｓｔｒｏｎ Ｃｈｅｍｉｃａｌ，Ｉｎｃ．社製品、硬化促進剤。
７）商品名：東洋紡績（株）製品、真球状アクリルビーズ、（ ）内は平均粒径。
【００５０】
【表３】

【００５１】
実施例１は（Ａ）成分としてハイブリッド系粉体塗料、実施例２は平均粒径の異なる樹脂ビーズを２種用いたハイブリッド系粉体塗料、実施例３はＰＣＭ（ブレコート金属鋼板）用ウレタン系粉体塗料を用いた本発明の熱硬化性粉体塗料である。上記粉体塗料を用いて塗装された塗膜は表３および図３〜５から明らかなように、実施例１〜３のいずれもサテン調の均一な凹凸模様が被塗物上に形成され、優れた意匠性と共に良好な化学性能および物理性能を示す塗膜が得られた。
【００５２】
比較例１〜２
表４に示した比較例１〜２の構成成分を、ドライブレンダー（商品名：ヘンシェルミキサー、三井三池化工機株式会社製）により約１分間均一に混合し、次に８０〜１００℃の温度条件で押出混練機（商品名：ブスコニーダーＰＲ−４６、ブス社製）を用いて溶融混練を行い、冷却後ハンマー式衝撃粉砕機で微粉砕したのち８０メッシュの金網で分級することで粉体塗料を製造した。得られた粉体塗料は、表５に示す塗装平均膜厚となるように−８０ｋｖ荷電で静電吹付法により所定の板厚の被塗物に塗装を行った。次いで表５に示した焼付条件において加熱硬化させた後、塗膜外観および塗膜物性について評価を行った。結果を表５および図６〜７に示す。
【００５３】
比較例３〜４
比較例３は、表４に示した（Ａ）成分をドライブレンダー（商品名：ヘンシェルミキサー、三井三池化工機株式会社製）により約１分間均一に混合し、次に８０〜１００℃の温度条件で押出混練機（商品名：ブスコニーダーＰＲ−４６、ブス社製）を用いて溶融混練を行い、冷却後（Ｂ）成分を添加してハンマー式衝撃粉砕機で微粉砕したのち８０メッシュの金網で分級し、粉体塗料を製造した。
比較例４は上記の比較例３と同様に溶融混練を行い、冷却後にハンマー式衝撃粉砕機で微粉砕した。その後、（Ｂ）成分を添加してから８０メッシュの金網で分級することで粉体塗料を製造した。得られた粉体塗料は、表５に示す塗装平均膜厚となるように−８０ｋｖ荷電で静電吹付法により所定の板厚の被塗物に塗装を行った。次いで表５に示した焼付条件において加熱硬化させた後、塗膜外観および塗膜物性について評価を行った。結果を表５および図６〜７に示す。
【００５４】
【表４】

【００５５】
【表５】

【００５６】
比較例１は、（Ｂ）成分として不定形樹脂を用いた粉体塗料である。得られた塗膜は図６に示すように、不定形樹脂に起因する不規則な角形の凸模様を形成し、目的とする丸みを帯びた凸模様は得られなかった。比較例２では、（Ｂ）成分として平均粒径８０μｍの樹脂ビーズを含有する粉体塗料を用いて１００μｍ以上に厚塗り塗装を行ったものである。得られた塗膜は図７に示すように、塗膜表面に充分な凸模様が形成されず意匠性に欠くものであった。一方、比較例３、４では得られた塗料は、いずれも塗装中に吹きムラを生じ模様は得られず、塗膜物性の低下も認められた。
【００５７】
【発明の効果】
本発明の凹凸模様形成性粉体塗料は、（Ｂ）成分の樹脂ビーズの形状が安定な硬化温度に加熱して（Ａ）成分の熱硬化性樹脂を硬化させ、サテン調の凹凸模様を有する塗膜を形成するための粉体塗料において、粉体塗料成分中の熱硬化性樹脂の加熱硬化温度において形状の安定な高分子化合物の球体からなる樹脂ビーズを含むため、均一かつ緻密で微細な丸みを帯びた突起状の模様で表現されるソフトで意匠性の高いサテン調の凹凸模様を有する塗膜を形成することができる。
【００５８】
本発明の凹凸模様形成性粉体塗料の製造方法は、（Ｂ）成分の樹脂ビーズの形状が安定な硬化温度に加熱して（Ａ）成分の熱硬化性樹脂を硬化させ、サテン調の凹凸模様を有する塗膜を形成するための粉体塗料の製造方法において、粉体塗料成分中の樹脂の溶融温度に加熱して高分子化合物の球体からなる樹脂ビーズを分散させるようにしたため、粉体塗料成分と樹脂ビーズが溶着一体化した粉体塗料を製造することができ、これにより上記のような凹凸模様を有し、かつ化学性能および物理性能、特に加工性および耐食性に優れた塗膜を形成することができる。
【００５９】
本発明の塗装物は、上記のような粉末塗料を被塗装物に塗布し、（Ｂ）成分の樹脂ビーズの形状が安定な硬化温度に加熱して（Ａ）成分の熱硬化性樹脂を硬化させ、樹脂ビーズの平均粒径を上回らない膜厚の塗膜を形成するため、上記のような優れた凹凸模様を有する塗膜を形成した塗装物を得ることができる。
【図面の簡単な説明】
【図１】（ａ）は実施形態の塗装物の表面の拡大斜視図、（ｂ）は断面図である。
【図２】（ａ）は比較例の塗装物の表面の拡大斜視図、（ｂ）は断面図である。
【図３】実施例１の３次元断面図である。
【図４】実施例２の３次元断面図である。
【図５】実施例３の３次元断面図である。
【図６】比較例１の３次元断面図である。
【図７】比較例２の３次元断面図である。
【符号の説明】
１ 塗装物
２ 被塗装物
３ 凹凸塗膜
４ 塗膜
５ 樹脂ビーズ
６ 凹部
７ 凸部
８ 樹脂粒状物[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a powder coating material for forming a soft, highly designable, satin-like uneven pattern, a method for producing the same, and a coated product.
[0002]
[Prior art]
In recent years, with the development of applications of powder coatings progressing, with the diversification of decorative expressions on objects to be coated, demands for powder coatings having design properties are increasing. In such a situation, there has been provided a powder coating material which changes the base tone of a material, for example, forms a concavo-convex pattern such as a matt tone, a velvet tone, a suede tone, a hammer tone finish, and imparts designability. As a method of forming such a concavo-convex pattern, for example, by using an additive such as a silicon compound, a unique repelling-like concavo-convex pattern can be formed on the surface of the coating film to give a design property.
[0003]
As another method, there is a method of forming a concavo-convex pattern by mixing resins having different properties into a powder coating. For example, Japanese Patent Publication No. 48-7686 discloses a resin powder having an average particle size of 200 mesh or less and a melt viscosity at 100 to 250 ° C. at room temperature of 100 poise or less, and an average particle size of 60 mesh or more and less than 200 mesh. And a powder coating characterized by a concavo-convex pattern mixed with a solid resin powder at room temperature having a melt viscosity at 100 to 250 ° C. of 100 poise or less. However, the coating film formed by this powder coating has shallow irregularities and is in the form of orange peel, which is poor in design. In addition, this method has a drawback that the expression pattern of the obtained coating film changes under coating conditions or when using recovered powder.
[0004]
As another method, a method in which a specific resin is dispersed in a main resin of a powder coating material to form a coating material is already known. For example, Japanese Patent Application Laid-Open No. 60-258270 discloses that a mixture containing a thermosetting resin which is solid at room temperature and a thermoplastic cellulose ether-based resin powder is melted, but the thermoplastic cellulose ether-based resin is dissolved. There is disclosed a powder coating material which is kneaded at a temperature not to be cooled, cooled and pulverized. However, in this powder coating, the thermosetting resin and the thermoplastic cellulose ether-based resin are kneaded at the same temperature, so that sufficient dispersion of the thermoplastic cellulose ether-based resin cannot be obtained. Not only is it not possible to obtain uniformity, but also a part of the coating film has a phenomenon of reaching the base material, and has a problem of lack of corrosion resistance.
[0005]
[Problems to be solved by the invention]
The design coating films obtained by these various methods are limited to the design expression by forming a continuous irregular uneven pattern on the surface of the object to be coated, and patterns with different tones have not been obtained. However, design orientation has been increasing mainly in OA equipment, measuring equipment, and the like, and there is a demand for a soft, moist, and highly designable coating film.
[0006]
The object of the present invention is to form such a soft and highly designable satin-like uneven pattern which is expressed by a uniform, dense and fine rounded protruding pattern in order to meet such a demand. An object of the present invention is to provide a powder coating material, an efficient production method thereof, and a coated product formed thereby.
[0007]
[Means for Solving the Problems]
The present invention relates to the following method for producing a powder coating having a concavo-convex pattern and a coated article.
(1) A powder for heating a thermosetting resin of component (A) by heating the resin beads of component (B) below to a stable curing temperature to form a coating film having a satin-like uneven pattern. Body paint,
(A) 60 to 99.9% by weight of a thermosetting powder coating component containing a thermosetting resin which is solid at room temperature, and
(B) Average particle size 30 -200 μm and stable in shape at the heat curing temperature of the component (A). Consists of polymer compound spheres Resin beads 0.1-40% by weight
And a pattern paint capable of forming a concavo-convex pattern.
(2) Among resin beads whose resin beads are made of polyamide resin, polyolefin resin, acrylic resin, epoxy resin, polyester resin, polyurethane resin, and melamine resin, and thermoplastic resin and thermosetting resin obtained by three-dimensionally cross-linking these. The powder coating according to the above (1), which is at least one member selected from the group consisting of:
(3) A powder for heating a thermosetting resin of the component (A) by heating the resin beads of the following component (B) to a stable curing temperature to form a coating film having a satin-like uneven pattern. A method for producing a body paint,
(A) 60 to 99.9% by weight of a thermosetting powder coating component containing a thermosetting resin which is solid at room temperature, and
(B) Average particle size 30 -200 μm and stable in shape at the heat curing temperature of the component (A). Consists of polymer compound spheres 0.1-40% by weight of resin beads
A method for producing a concavo-convex pattern-forming powder coating, wherein the component (B) is dispersed in the component (A) by heating to a temperature at which the resin component in the component (A) melts.
(4) The powder coating material described in the above (1) or (2) is applied to an object to be coated, and the shape of the resin beads of the component (B) is heated to a curing temperature at which the component is stable. A coated product obtained by curing a resin and forming a coating film having a satin-like uneven pattern such that the cured coating film of the component (A) has a thickness not exceeding the average particle diameter of the component (B).
[0008]
The uneven pattern forming powder coating of the present invention, The resin beads of the following component (B) are heated to a stable curing temperature to cure the thermosetting resin of the component (A) and form a powder coating for forming a coating film having a satin-like uneven pattern. So, It contains a thermosetting powder coating component as the component (A) and resin beads as the component (B). The thermosetting powder coating component (A) contains a thermosetting resin that is solid at room temperature and other components added as necessary, and has been conventionally used as a thermosetting powder coating material. Components can be used as is.
[0009]
In the powder coating of the present invention, the thermosetting resin that is solid at room temperature used as the component (A) is not particularly limited, but the self-curing resin used as a coating forming component in the conventional thermosetting powder coating is used. Known thermosetting resins such as a crosslinking type, a type containing a curing agent, and a type after adding a curing agent can be used. As a general example of such a thermosetting resin, for example, an epoxy-based, polyester-based, acrylic-based, or thermosetting solid thermosetting resin such as a fluorine-based resin is preferably used as a main agent, and melamine as a curing agent is also used. Blocked isocyanates, polybasic acids / amides, glycidyl compounds, and polymers thereof can be used.
[0010]
As the component (A), a pigment can be added as another component, if necessary, in the range of 0.01 to 100 parts by weight based on 100 parts by weight of the thermosetting resin. Examples of the pigment include inorganic pigments such as titanium dioxide, carbon black, and iron oxide; extenders such as talc, precipitated barium sulfate, silica, and calcium carbonate; and organic pigments such as a cyanine blue azo pigment. In addition, as in the case of the conventional powder coating, a curing accelerator, a leveling agent, a defoaming agent, an antioxidant, a modifier such as an ultraviolet absorber, and other additives as other components, and other additives are added to 100 parts by weight of the thermosetting resin. It can be added in the range of 0.01 to 30 parts by weight.
[0011]
The resin beads used as the component (B) of the present invention have an average particle size. 30 It is a sphere made of a polymer compound having a shape within a range of from about 200 μm and having a stable shape at the heat curing temperature of the component (A). The shape of the resin beads is preferably a true sphere, but may be a pseudo sphere having a slightly collapsed shape. Columnar bodies, needle-like bodies, irregularly shaped bodies, etc. are not preferred because dispersibility during the production of the coating material is reduced and the intended satin pattern is impaired.
[0012]
The resin beads are preferably made of a resin having affinity or compatibility with the thermosetting resin (A). From the viewpoint of preventing thermal deformation at the time of heating, a thermoplastic resin or a thermosetting resin having a three-dimensional cross-linked structure is desirable. However, if the shape is stable at the heat-curing temperature of the component (A), a high non-cross-linking property is obtained. It may be a molecular compound. Further, the resin beads may contain various reactive functional groups, but are desirably inert to the reactive functional groups of the component (A).
[0013]
These resin beads are not particularly limited in their resin composition and synthesis route as long as they have the average particle size and the shape, nylon, polyolefin, acrylic resin, epoxy resin, polyester resin, urethane resin, melamine resin, A high molecular compound such as a thermoplastic resin or a thermosetting resin obtained by three-dimensionally cross-linking these can be suitably used. Further, as the resin beads, colored beads containing an organic pigment and / or an inorganic pigment can be used according to a desired pattern tone.
[0014]
As a method for producing these resin beads, for example, in the case of an acrylic resin, the resin beads can be produced by emulsion polymerization of an α, β-unsaturated monomer and a polyfunctional unsaturated monomer. In addition, resin beads such as an epoxy resin can be produced by performing a crosslinking reaction at the time of emulsification after solution polymerization and removing the solvent. Other resins can also be manufactured by a known method for manufacturing each resin.
[0015]
Commercially available resin beads can also be used. Representative examples of commercially available resin beads include polyamide resin (nylon) such as Orgasol powder (trade name: Nippon Rilsan Co., Ltd.) and diamide (trade name: Daicel Huls Co., Ltd.). XM (trade name: Mitsui Petrochemical Industry Co., Ltd.) and the like. Further, examples of the acrylic resin include Julimar MB (trade name: Nippon Pure Chemical Co., Ltd.), Tuftic AR (trade name: Toyobo Co., Ltd.), Lab Color (trade name: Dainichi Seika Kogyo Co., Ltd.), Techpolymer MBX , Techpolymer SBX, Techpolymer SME (trade name: Sekisui Chemical Co., Ltd.), Fine Pearl PB, Fine Pearl PM (trade name: Sumitomo Chemical Co., Ltd.), SPG type, SP type (trade name: Soken Chemical Co., Ltd.) Company). Further, as a polyester resin, VALINAX FC (trade name: Mitsui Toatsu Chemicals Co., Ltd.), and as a urethane resin, Vernox CFB (trade name: Dainippon Ink and Chemicals, Inc.) and urethane beads (products of Sekisui Plastics Co., Ltd.) ), Deco Silk (trade name: Sakai Shoji Co., Ltd.), etc. For melamine resin, Eposter L (trade name: Nippon Shokubai Co., Ltd.), Bell Pearl R, Bell Pearl H, Bell Pearl C (trade name: Kanebo Co., Ltd.), Univex-C, Thermoset resin beads such as Univex-WA-C and GCP series (product name: Unitika Ltd.) can be mentioned.
[0016]
Regarding the use of these resin beads, one of an arbitrary type may be used alone, or a combination of two or more types may be used depending on a desired pattern tone irrespective of color or colorless.
[0017]
The average particle size of the resin beads used as the component (B) is as follows: 30 The thickness may be within the range of 200 to 200 μm, but is preferably within the range of 30 to 150 μm. Here, if the average particle size exceeds 200 μm, the obtained pattern becomes coarse, which not only impairs the uniformity and design of the obtained pattern, but also lowers the physical properties of the coating film. The average particle size is 30 If it is less than μm, it is difficult to form a pattern on the coating film, and a matting effect may occur, which is not preferable.
[0018]
The particle size of the resin beads may be selected from those having an appropriate particle size depending on the desired pattern tone, and may be used alone or in combination of two or more. For example, when only resin beads having an average particle size of less than 50 μm are used, a generally obtained satin pattern tends to be shallow, but beads having an average particle size of less than 50 μm and resin beads having an average particle size of 50 to 200 μm are used. By using in combination, a good satin pattern can be obtained.
[0019]
The uneven pattern-forming powder coating material of the present invention comprises 60 parts of the thermosetting powder coating component (A) containing the thermosetting resin and the pigments, modifiers and other additives added as required. It is a powder coating containing from 9 to 99.9% by weight, preferably from 70 to 95% by weight, and from 0.1 to 40% by weight, preferably from 5 to 30% by weight of the resin beads of the component (B). A satin-like pattern can be obtained even when the amount of the resin beads exceeds 40% by weight, but the physical properties of the coating film deteriorate with respect to workability and corrosion resistance. It becomes a film.
[0020]
In the powder coating of the present invention, it is desirable that the resin beads of the component (B) are uniformly dispersed in the powder coating of the component (A). In this case, the resin beads need to be uniformly dispersed in the component (A) while maintaining a spherical shape. In order that the components (A) and (B) do not separate during the preservation, transportation and painting operations, it is important that both components are in a molten and integrated state.
[0021]
In the method for producing a concavo-convex pattern-forming powder coating material of the present invention, the components (A) and (B) are heated to a temperature at which the resin component in the component (A) melts, and the component (B) is heated to the component (A). It is a method of dispersing in components. In this case, at the temperature at which the resin component of the component (A) melts, the softening temperature of the component (B) is adjusted so that the resin component of the component (B) maintains a spherical shape. Must be higher than the temperature.
[0022]
In the above production method, the components (A) and (B) are simultaneously kneaded at the temperature at which the resin component in the component (A) melts during the production of the powder coating, and the resin beads are added to the molten powder coating. Can be dispersed. This is not a special method, and the resin beads can be dispersed by kneading according to ordinary powder coating production.
[0023]
Specifically, the powder coating is produced by adding a predetermined amount of the component (B) to a mixture of the main component (A) of the thermosetting resin, a pigment, an additive, and the like, mixing the mixture with a drive render, and then extruding the mixture. Using a kneader, a single-screw or twin-screw extruder or the like, melt kneading is performed in a temperature range in which the resin component (A) is melted, usually at 80 to 120 ° C., and pelletized, followed by cooling. This is finely pulverized by an impact pulverizer, a pneumatic pulverizer or the like, and classified to produce a powder coating. It is necessary that the resin beads of the component (B) not be deformed by heating and have such a strength that they are not crushed even when crushed.
[0024]
Here, when the component (B) is added and dispersed at the time of pulverization after melt kneading of the component (A) or at the time of classification without dispersing the component (B) in the component (A), the ( B) Not only the content of the component becomes unstable between production lots, but also the uniformity of the pattern is impaired due to a change in coating efficiency at the time of coating, and a change in the pattern tone occurs when the recovered powder is used. Further, non-uniformity of the formed pattern causes deterioration in physical properties of the coating film such as workability and corrosion resistance, which is not preferable.
[0025]
The coating method using the concavo-convex pattern-forming powder coating material of the present invention is a method for applying the powder coating material by a coating method in a normal powder coating material such as an electrostatic spraying method, a fluid immersion method or an electrostatic fluid immersion method. And then apply (B) The shape of the resin beads of the component has a stable curing temperature Heat and melt Curing the thermosetting resin of component (A) By doing so, a coating film having a satin-like uneven pattern that is soft and highly designable is formed, and a coated product is obtained. In this case, the blending and application amount of the powder coating are selected so that the cured coating film formed by the component (A) has a thickness not exceeding the average particle diameter of the resin beads of the component (B). Among the paint finishing methods, an electrostatic spraying method is particularly preferable.
[0026]
The material and shape are not particularly limited as long as they can withstand the heating conditions at the time of forming the coating film, and any object can be coated. Examples of the material of the object to be coated include a steel plate having a thickness of about 0.2 to 2 mm, a galvanized steel plate, an aluminum plate, a metal plate such as a stainless steel plate, glass, ceramic, and a molded product thereof. it can.
[0027]
In order to apply the powder coating to the object to be coated as described above, the object to be coated is uniformly coated by a commercially available electrostatic coating machine (loading voltage: -50 to -90 kV) or other powder coating methods. It is heated and melted in a hot air baking furnace, infrared furnace, induction heating furnace, etc., and cured to form a coating film.
The conditions for the heat curing depend on the type of the thermosetting powder coating material of the component (A) and the composition of the coating material, but the temperature of the object to be coated is usually 150 to 280 ° C. for 1 to 30 minutes, preferably. The temperature is suitably from 170 ° C. to 250 ° C. for 3 to 20 minutes.
[0028]
It is appropriate that the coating thickness is usually 30 to 150 μm, preferably 50 to 80 μm in average. At this time, if the film thickness is adjusted so as not to exceed the average particle size of the component (B) to be used, a uniform, dense, finely-coated projection film having rounded projections is formed, and a soft, high-design satin-like coating is obtained. An uneven pattern is obtained. Here, the average film thickness is the average value of the entire film thickness including the convex portions and the concave portions, and is arithmetically determined from the area of the object to be coated, the applied weight of the paint used for coating, and the specific gravity of the paint. Can be.
[0029]
When the range of the pattern is limited based on the parameters of the surface roughness and the undulation according to “JIS B-0601 (1994) Surface roughness definition and display” for the concavo-convex pattern formed as described above, the pattern becomes a rounded protruding pattern. The above-mentioned parameters of the surface roughness and undulation are desirably within the range of Table 1 below at all five or more arbitrarily selected surface roughness measurement points on the coating film surface.
[0030]
Here, the center line average roughness Ra, the average interval Sm of the concave and convex portions, and the average interval S of the local peaks express the density of the above-mentioned projecting pattern, and the ten-point average roughness Rz expresses the height of the pattern. And the following values:
Ra: Average value of absolute value deviation from the average line.
Rz: the sum of the average value of the absolute values of the five points from the higher side of the convex portion and the average value of the absolute values of the five points from the lower side of the concave portion for each reference length.
Sm: Average value of the interval of one cycle of the concavo-convex obtained from the intersection of the roughness curve and the average line.
S: Average value of the interval between adjacent local protrusions.
[0031]
[Table 1]

[0032]
In the coating film formed as described above, a uniform, dense and fine rounded protruding pattern is formed by the resin beads, so that a soft, highly designable, satin-like uneven pattern can be obtained. And, since the powder coating component (A) and the resin beads (B) are integrated by welding, a coating film excellent in chemical performance, physical performance, especially workability and corrosion resistance can be obtained. Whether or not the projections of the concavo-convex pattern are rounded can be visually observed, but can be visualized by drawing an enlarged three-dimensional sectional view.
[0033]
When crushed or irregular resin granules are used in place of the resin beads of the component (B), a coating film having angular projections is formed, and a coating film having a cold feeling and a poor texture is formed. Since the coating film is peeled off from the film, a coating film having inferior chemical performance and physical performance is obtained.
[0034]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an enlarged view showing a coated article formed by applying a powder coating composed of a powder coating component of the component (A) and a resin bead of the component (B) to form an uneven coating film, and FIG. FIG. 2B is a cross-sectional view.
[0035]
In FIG. 1, a coating object 1 has an uneven coating film 3 formed on a surface of a coating object 2. In the uneven coating film 3, resin beads 5 of the component (B) are embedded in a coating film 4 formed by the component (A). The portion where the resin beads 5 do not exist is formed as a concave portion 6, and the portion where the resin beads 5 protrude is formed as a convex portion 7.
[0036]
In the uneven coating film 3, the convex portion 7 has the spherical resin beads 5 protruding therefrom and the coating film 4 extends in a skirt shape, so that the rounded convex portion 7 is formed, and the soft and high-design satin-like unevenness is formed. A coating is obtained.
[0037]
FIG. 2A is a perspective view showing, as a comparative example, an enlarged painted product using crushed resin granules 8 instead of the resin beads 5 of FIG. 1, and FIG. 2B is a sectional view thereof. In FIG. 2, since the convex portion 7 is formed by the crushed resin granules 8, the convex portion 7 becomes an angular projection, a soft uneven pattern is not obtained, and a coating film with a cold feeling and a poor texture is obtained.
[0038]
【Example】
Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.
[0039]
In each example, physical performance such as coating film performance was determined as follows.
(1) Specular gloss
The values when the incident angle and the light receiving angle are 60 degrees are shown in accordance with JIS K-5400 (1990) 7.6.
(2) Pencil hardness
The measurement was performed according to JIS K-5400 (1990) 8.4.2 Hand-drawing method.
[0040]
(3) Erichsen value
It carried out according to JIS K-5400 (1990) 8.2.2 breaking distance method.
(4) Impact resistance
The measurement was performed according to JIS K-5400 (1990) 8.3.2 Dupont method.
(5) Flex resistance
The measurement was performed according to JIS K-5400 (1990) 8.1.
[0041]
(6) Workability test
A 180 ° bending test is performed using a vice with a material piece sandwiched between test pieces. Shows the number of material pieces that do not cause coating defects such as cracks on the curved surface of the coating. In this case, for example, a pass value when two material pieces are sandwiched is expressed as 2T.
[0042]
(7) Salt spray resistance
According to JIS K-5400 (1990) 9.1, a test was conducted continuously for 300 hours after cross-cutting the coating film surface. In the peeling test, the tape was peeled on the cut surface, and the maximum value of the width peeled from the cut center line was shown.
[0043]
(8) Surface condition
Judgment was made by visual observation according to the following criteria.
Normal: A state in which the projections form an independent projection pattern.
Slightly dense: a state in which a protruding pattern is formed by partially overlapping convex portions.
Relatively dense: a state in which most of the projections overlap to form a projecting pattern.
[0044]
(9) Surface roughness measurement
According to JIS B-0601 (1994) Surface Roughness One Definition and Display, parameters of surface roughness and waviness were measured, and the range of pattern tone was expressed numerically.
[Parameters related to amplitude]
Ra: center line average roughness (μm), Rz: ten point average roughness (μm)
[Parameters related to wavelength]
Sm: average distance between irregularities (mm), S: average distance between local peaks (mm)
[0045]
(10) Three-dimensional sectional view
The three-dimensional cross-sectional view is obtained by using a three-dimensional surface roughness profile measuring device (trade name: Tokyo Seimitsu Co., Ltd., Surfcom E-RC-XY3B) to calculate the longitudinal curve of the cross-sectional curve of the coating film surface on which the inclination is not corrected Is 100 times, the lateral magnification, and the front-back magnification are 50 times, and the pitch is 20 μm.
[0046]
(11) Evaluation of pattern tone
From the results of visual observation, three-dimensional sectional view and surface roughness measurement, comprehensive judgment was made according to the following criteria.
Good: A uniform, dense, finely rounded design-like coating film having a protruding pattern is formed, and the parameters attributable to the protruding pattern are within the preferable ranges in Table 1.
Bad: Other than the above.
[0047]
Examples 1-3
The components of Examples 1 to 3 shown in Table 2 were uniformly mixed for about 1 minute by a drive render (trade name: Henschel mixer, manufactured by Mitsui Miike Kakoki Co., Ltd.), and then temperature conditions of 80 to 100 ° C. Is melt kneaded using an extrusion kneader (trade name: Buscon Kneader PR-46, manufactured by Bus), cooled, pulverized finely with a hammer type impact pulverizer, and then classified with an 80 mesh wire mesh to obtain a powder coating. Manufactured. The obtained powder coating material was applied to an object having a predetermined thickness by electrostatic spraying with -80 kv charge so as to have a coating average film thickness shown in Table 3. Next, after curing by heating under the baking conditions shown in Table 3, the appearance and physical properties of the coating film were evaluated. The results are shown in Table 3 and FIGS.
[0048]
[Table 2]

[0049]
Notes for Table 2
1) Trade name: DSM Resins product, polyester resin, acid value 35 mgKOH / g.
2) Trade name: product of Dainippon Ink and Chemicals, polyester resin, hydroxyl value 30 mgKOH / g.
3) Trade name: product of Shell Chemicals, epoxy resin, epoxy equivalent 650 g / Eq.
4) Trade name: Huels product, adduct isocyanate curing agent, isocyanate equivalent 280 g / Eq.
5) Trade name: Monsant product, leveling agent.
6) Trade name: Estron Chemical, Inc. Products, curing accelerators.
7) Trade name: Toyobo Co., Ltd. product, spherical acrylic beads.
[0050]
[Table 3]

[0051]
Example 1 is a hybrid powder coating as the component (A), Example 2 is a hybrid powder coating using two types of resin beads having different average particle sizes, and Example 3 is a urethane type for PCM (Burecoat metal steel plate). It is a thermosetting powder coating of the present invention using a powder coating. As is clear from Table 3 and FIGS. 3 to 5, all of Examples 1 to 3 had a uniform satin-like uneven pattern formed on the object to be coated, as is clear from Table 3 and FIGS. A coating film showing good chemical performance and physical performance with excellent design properties was obtained.
[0052]
Comparative Examples 1-2
The components of Comparative Examples 1 and 2 shown in Table 4 were uniformly mixed for about 1 minute by a drive render (trade name: Henschel mixer, manufactured by Mitsui Miike Kakoki Co., Ltd.), and then temperature conditions of 80 to 100 ° C. The mixture is melt-kneaded using an extrusion kneader (trade name: Buscon Kneader PR-46, manufactured by Bus), cooled, pulverized by a hammer-type impact pulverizer, and then classified by an 80-mesh wire mesh to obtain a powder coating. Manufactured. The obtained powder coating material was applied to an object having a predetermined thickness by electrostatic spraying with -80 kv charge so as to have a coating average film thickness shown in Table 5. Then, after curing by heating under the baking conditions shown in Table 5, the appearance and physical properties of the coating film were evaluated. The results are shown in Table 5 and FIGS.
[0053]
Comparative Examples 3 and 4
In Comparative Example 3, the component (A) shown in Table 4 was uniformly mixed for about 1 minute by a drive render (trade name: Henschel mixer, manufactured by Mitsui Miike Kakoki Co., Ltd.), and then temperature conditions of 80 to 100 ° C. And melt kneading using an extrusion kneader (trade name: Buscon Kneader PR-46, manufactured by Bus), and after cooling, adding the component (B), finely pulverizing with a hammer impact pulverizer, and then using an 80 mesh wire mesh. After classification, a powder coating was produced.
In Comparative Example 4, melt kneading was performed in the same manner as in Comparative Example 3 described above, and after cooling, the mixture was finely pulverized with a hammer impact pulverizer. Thereafter, the powder coating was manufactured by adding the component (B) and then classifying it with a 80-mesh wire mesh. The obtained powder coating material was applied to an object having a predetermined thickness by electrostatic spraying with -80 kv charge so as to have a coating average film thickness shown in Table 5. Then, after curing by heating under the baking conditions shown in Table 5, the appearance and physical properties of the coating film were evaluated. The results are shown in Table 5 and FIGS.
[0054]
[Table 4]

[0055]
[Table 5]

[0056]
Comparative Example 1 is a powder coating using an amorphous resin as the component (B). As shown in FIG. 6, the obtained coating film formed an irregular square convex pattern due to the irregular resin, and the intended rounded convex pattern could not be obtained. In Comparative Example 2, a thick coating of 100 μm or more was performed using a powder coating containing resin beads having an average particle size of 80 μm as the component (B). As shown in FIG. 7, the obtained coating film did not have a sufficient convex pattern formed on the surface of the coating film and lacked design properties. On the other hand, in Comparative Examples 3 and 4, all of the obtained paints caused unevenness in blowing during coating, no pattern was obtained, and a decrease in physical properties of the coating film was also observed.
[0057]
【The invention's effect】
The uneven pattern-forming powder coating material of the present invention has a satin-like uneven pattern by heating the (A) component thermosetting resin by heating to a curing temperature at which the shape of the resin beads (B) is stable. In powder coating for forming a coating film, the shape of the thermosetting resin in the powder coating component is stable at the heat curing temperature. Consists of polymer compound spheres Since the resin beads are included, it is possible to form a coating film having a soft, highly designable, satin-like uneven pattern expressed by a uniform, dense, fine, rounded projection pattern.
[0058]
The method for producing a concavo-convex pattern-forming powder coating according to the present invention is characterized in that the resin beads of the component (B) are heated to a stable curing temperature to cure the thermosetting resin of the component (A). In the method for producing a powder coating for forming a coating film having a pattern, heating to the melting temperature of the resin in the powder coating component Consists of polymer compound spheres Since the resin beads are dispersed, it is possible to produce a powder coating in which the powder coating component and the resin beads are welded and integrated, thereby having the above-mentioned uneven pattern, and having chemical and physical properties, In particular, a coating film having excellent workability and corrosion resistance can be formed.
[0059]
The coated material of the present invention is applied to the object to be coated with the powder coating as described above, The shape of the resin beads of the component (B) is heated to a stable curing temperature to cure the thermosetting resin of the component (A), Since a coating film having a thickness not exceeding the average particle size of the resin beads is formed, it is possible to obtain a coated article having a coating film having an excellent uneven pattern as described above.
[Brief description of the drawings]
FIG. 1A is an enlarged perspective view of a surface of a coated article according to an embodiment, and FIG. 1B is a cross-sectional view.
FIG. 2A is an enlarged perspective view of the surface of a coated article of a comparative example, and FIG. 2B is a cross-sectional view.
FIG. 3 is a three-dimensional cross-sectional view of the first embodiment.
FIG. 4 is a three-dimensional sectional view of a second embodiment.
FIG. 5 is a three-dimensional sectional view of a third embodiment.
FIG. 6 is a three-dimensional sectional view of Comparative Example 1.
FIG. 7 is a three-dimensional sectional view of Comparative Example 2.
[Explanation of symbols]
1 painted objects
2 Objects to be painted
3 Uneven coating
4 Coating
5 Resin beads
6 recess
7 convex
8 Resin granules

Claims (4)

The resin beads of the following component (B) are heated to a stable curing temperature to cure the thermosetting resin of the component (A) and form a powder coating for forming a coating film having a satin-like uneven pattern. So,
(A) 60 to 99.9% by weight of a thermosetting powder coating component containing a thermosetting resin which is solid at ordinary temperature; and (B) an average particle size of 30 to 200 μm, and a heat curing temperature of the component (A). 0.1-40% by weight of resin beads consisting of spheres of a polymer compound having a stable shape
And a pattern paint capable of forming a concavo-convex pattern. The resin beads are selected from a polyamide resin, a polyolefin resin, an acrylic resin, an epoxy resin, a polyester resin, a polyurethane resin, and a melamine resin, and a resin bead made of a thermoplastic resin and a thermosetting resin obtained by three-dimensionally cross-linking these resins. The powder coating according to claim 1, which is at least one kind. The shape of the resin beads of the following component (B) is heated to a stable curing temperature to cure the thermosetting resin of the component (A) and form a powder coating for forming a coating film having a satin-like uneven pattern. A manufacturing method,
(A) 60 to 99.9% by weight of a thermosetting powder coating component containing a thermosetting resin which is solid at ordinary temperature; and (B) an average particle size of 30 to 200 μm, and a heat curing temperature of the component (A). In 0.1 to 40% by weight of resin beads composed of spheres of a polymer compound having a stable shape,
A method for producing a concavo-convex pattern-forming powder coating, wherein the component (B) is dispersed in the component (A) by heating to a temperature at which the resin component in the component (A) melts. Applying the powder coating material according to claim 1 to an object to be coated, heating the resin beads of the component (B) to a stable curing temperature to cure the thermosetting resin of the component (A), A coated article having a coated film having a satin-like uneven pattern such that the cured coating film of the component (A) has a thickness not exceeding the average particle size of the component (B).

Images