JP4900545B2 - Iron-based black composite pigment and method for producing the same, paint using the iron-based black composite pigment, and rubber / resin composition colored with the iron-based black composite pigment - Google Patents

Description

【００４５】
【化２】

【００４６】
【化３】

【００４７】
カーボンブラック微粒子粉末の付着効果及び脱離率を考慮すると、メチルハイドロジェンシロキサン単位を有するポリシロキサン、ポリエーテル変成ポリシロキサン及び末端がカルボン酸で変成された末端カルボン酸変成ポリシロキサンが好ましい。
【００４８】
ポリシロキサンの被覆量は、ポリシロキサン被覆黒色酸化鉄粒子粉末又はポリシロキサン被覆黒色含水酸化鉄粒子粉末に対し、Ｓｉ換算で０．０２〜５．０重量％であることが好ましい。より好ましくは、０．０３〜４．０重量％、更により好ましくは０．０５〜３．０重量％である。
【００４９】
０．０２重量％未満の場合には、黒色度の優れた鉄系黒色複合顔料を得ることが困難である。
【００５０】
５．０重量％を超える場合には、得られる鉄系黒色複合顔料の黒色度を改良できる程度にカーボンブラックを黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末の粒子表面に十分付着させることができるため、必要以上に添加する意味がない。
【００５１】
カーボンブラックの付着量は、黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末１００重量部に対して１〜３０重量部である。
【００５２】
１重量部未満の場合には、カーボンブラックの付着量が不十分であり、十分な黒色度を有する鉄系黒色複合顔料を得ることが困難となる。
【００５３】
３０重量部を超える場合には、得られる鉄系黒色複合顔料は十分な黒色度を有しているが、カーボンブラックの付着量が多いため、カーボンブラックが脱離しやすくなり、その結果、鉄系黒色複合顔料のビヒクル中や樹脂組成物中への分散性が低下する。
【００５４】
カーボンブラックの付着厚みは、０．０４μｍ以下が好ましく、より好ましくは０．０３μｍ以下、更に好ましくは０．０２μｍ以下である。
【００５５】
本発明に係る鉄系黒色複合顔料は、必要により、黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末の粒子表面をあらかじめ、アルミニウムの水酸化物、アルミニウムの酸化物、ケイ素の水酸化物及びケイ素の酸化物から選ばれた１種又は２種以上（以下、「アルミニウムの水酸化物等による被覆」という。）で被覆しておいてもよく、アルミニウムの水酸化物等で被覆しない場合に比べ、鉄系黒色複合顔料のビヒクル中や樹脂組成物中への分散性がより向上する。
【００５６】
アルミニウムの水酸化物等の被覆量は、アルミニウムの水酸化物等が被覆された黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末に対してＡｌ換算、ＳｉＯ₂換算、又はＡｌ換算量とＳｉＯ₂換算量との総和で０．０１〜５０重量％が好ましい。
【００５７】
０．０１重量％未満である場合には、鉄系黒色複合顔料のビヒクル中や樹脂組成物中への分散性改良効果が得られない。
【００５８】
５０重量％を超える場合には、鉄系黒色複合顔料のビヒクル中や樹脂組成物中への分散性改良効果が十分に得られるため、必要以上に被覆する意味がない。
【００５９】
アルミニウムの水酸化物等で被覆されている本発明に係る鉄系黒色複合顔料は、アルミニウムの水酸化物等で被覆されていない本発明に係る鉄系黒色複合顔料の場合とほぼ同程度の粒子サイズ、幾何標準偏差値、ＢＥＴ比表面積値、黒色度Ｌ^*値及びカーボンブラックの脱離率を有している。
【００６０】
次に、本発明に係る鉄系黒色複合顔料の製造法について述べる。
【００６１】
本発明における芯粒子粉末である粒状マグネタイト粒子粉末は、第一鉄塩水溶液と水酸化アルカリ水溶液とを反応して得られる水酸化第一鉄コロイドを含む懸濁液中に酸素含有ガスを通気して酸化する、所謂、湿式法により得られる。
【００６２】
粒状のマンガン含有ヘマタイト粒子粉末は、上記湿式法により生成した粒状マグネタイト粒子粉末を全Ｆｅに対して８〜１５０原子％のマンガン化合物で被覆した粒状マグネタイト粒子粉末又は粒状マグネタイト粒子粉末を生成する上記湿式法においてマンガンの存在下で反応させて全Ｆｅに対して８〜１５０原子％のマンガンを含有する粒状マグネタイト粒子粉末を生成し、次いで濾別、水洗、乾燥して得られた粒状マンガン含有マグネタイト粒子粉末のいずれかを、空気中７５０〜１０００℃で加熱処理することにより得られる。
【００６３】
針状マグネタイト粒子粉末や紡錘状マグネタイト粒子粉末は、第一鉄塩水溶液と水酸化アルカリ水溶液、炭酸アルカリ水溶液又は水酸化アルカリ水溶液・炭酸アルカリ水溶液とを反応して得られる水酸化第一鉄コロイド、炭酸鉄及び鉄含有沈殿物のいずれかを含む懸濁液中に酸素含有ガスを通気して酸化する、所謂、湿式法により針状ゲータイト粒子粉末や紡錘状ゲータイト粒子粉末を生成し、該針状ゲータイト粒子粉末を濾別、水洗後、還元性雰囲気下、３００〜５００℃で加熱還元処理することにより得られる。
【００６４】
針状又は紡錘状のマンガン含有ヘマタイト粒子粉末は、後出の方法により得られる全Ｆｅに対して８〜１５０原子％のマンガンを含有する針状又は紡錘状のゲータイト粒子粉末を空気中４００〜８００℃で加熱脱水処理することにより得ることができる。
【００６５】
本発明における針状又は紡錘状のマンガン含有ゲータイト粒子粉末は、針状又は紡錘状ゲータイト粒子を生成する前記湿式法において、マンガンの存在下で反応させて全Ｆｅに対して８〜１５０原子％のマンガンを含有させることにより得られる。
【００６６】
黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末のポリシロキサンによる被覆は、黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末とポリシロキサンとを機械的に混合攪拌したり、黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末にポリシロキサンを噴霧しながら機械的に混合攪拌すればよい。添加したポリシロキサンは、ほぼ全量が黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末の粒子表面に被覆される。
【００６７】
ポリシロキサンを均一に粒子表面に被覆するためには、黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末の凝集をあらかじめ粉砕機を用いて解きほぐしておくことが好ましい。
【００６８】
黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末とポリシロキサンとの混合攪拌やカーボンブラック微粒子粉末と粒子表面にポリシロキサンが被覆されている黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末との混合攪拌をするための機器としては、粉体層にせん断力を加えることのできる装置が好ましく、殊に、せん断、へらなで及び圧縮が同時に行える装置、例えば、ホイール形混練機、ボール型混練機、ブレード型混練機、ロール型混練機を用いることができる。本発明の実施にあたっては、ホイール型混練機がより効果的に使用できる。
【００６９】
上記ホイール型混練機としては、具体的に、エッジランナー（「ミックスマラー」、「シンプソンミル」、「サンドミル」と同義語である）、マルチマル、ストッツミル、ウエットパンミル、コナーミル、リングマラー等があり、好ましくはエッジランナー、マルチマル、ストッツミル、ウエットパンミル、リングマラーであり、より好ましくはエッジランナーである。上記ボール型混練機としては、具体的に、振動ミル等がある。上記ブレード型混練機としては、具体的に、ヘンシェルミキサー、プラネタリーミキサー、ナウタミキサー等がある。上記ロール型混練機としては、具体的に、エクストルーダー等がある。
【００７０】
混合撹拌時における条件は、黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末の粒子表面にポリシロキサンができるだけ均一に被覆されるように、線荷重は１９．６〜１９６０Ｎ／ｃｍ（２〜２００Ｋｇ／ｃｍ）、好ましくは９８〜１４７０Ｎ／ｃｍ（１０〜１５０Ｋｇ／ｃｍ）、より好ましくは１４７〜９８０Ｎ／ｃｍ（１５〜１００Ｋｇ／ｃｍ）、処理時間は５〜１２０分、好ましくは１０〜９０分の範囲で処理条件を適宜調整すればよい。なお、撹拌速度は２〜２０００ｒｐｍ、好ましくは５〜１０００ｒｐｍ、より好ましくは１０〜８００ｒｐｍの範囲で処理条件を適宜調整すればよい。
【００７１】
ポリシロキサンの添加量は、黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末１００重量部に対して０．１５〜４５重量部が好ましい。０．１５重量部未満の場合には、得られる鉄系黒色複合顔料の黒色度を改良できる程度に黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末の粒子表面にカーボンブラックを十分付着させることが困難である。４５重量部を超える場合には、得られる鉄系黒色複合顔料の黒色度を改良できる程度に黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末の粒子表面にカーボンブラックを十分付着させることができるため、必要以上に添加する意味がない。
【００７２】
次いで、ポリシロキサンが被覆されている黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末に、カーボンブラック微粒子粉末を添加し、混合攪拌してポリシロキサン被覆にカーボンブラックを付着させる。必要により更に、乾燥を行ってもよい。
【００７３】
付着処理に用いるカーボンブラック微粒子粉末は、市販のファーネスブラック、チャンネルブラック等を使用することができ、具体的には、＃３０５０、＃３１５０、＃３２５０、＃３７５０、＃３９５０、ＭＡ１００、ＭＡ７、＃１０００、＃２４００Ｂ、＃３０、ＭＡ７７、ＭＡ８、＃６５０、ＭＡ１１、＃５０、＃５２、＃４５、＃２２００Ｂ、ＭＡ６００等（商品名：三菱化学株式会社（製））シースト９Ｈ、シースト７Ｈ、シースト６、シースト３Ｈ、シースト３００、シーストＦＭ等（商品名、東海カーボン株式会社（製））、Ｒａｖｅｎ １２５０、Ｒａｖｅｎ ８６０、Ｒａｖｅｎ １０００、Ｒａｖｅｎ １１９０ＵＬＴＲＡ（商品名：コロンビヤン・ケミカルズ・カンパニー（製））、ケッチェンブラックＥＣ、ケッチェンブラックＥＣ６００ＪＤ（商品名：ケッチェンブラック・インターナショナル株式会社（製））、ＢＬＡＣＫ ＰＥＡＲＬＳ−Ｌ、ＢＬＡＣＫ ＰＥＡＲＬＳ １０００、ＢＬＡＣＫ ＰＥＡＲＬＳ ４６３０、ＶＵＬＣＡＮ ＸＣ７２、ＲＥＧＡＬ ６６０、ＲＥＧＡＬ ４００（商品名：キャボット・スペシャルティ・ケミカルズ・インク（製））等が使用できる。
【００７４】
ポリシロキサンとの親和性を考慮すれば、ＭＡ−１００、ＭＡ７、＃１０００、＃２４００Ｂ、＃３０、ＢＬＡＣＫ ＰＥＡＲＬＳ−Ｌ及びＢＬＡＣＫ ＰＥＡＲＬＳ ４６３０が好ましい。
【００７５】
付着処理に用いるカーボンブラック微粒子粉末の平均粒子径は０．００５〜０．０５μｍ程度、より好ましくは０．０１０〜０．０３５μｍ程度である。
【００７６】
０．００５μｍ未満の場合には、カーボンブラック微粒子粉末があまりに微細となるため、取扱いが困難となる。
【００７７】
０．０５μｍを超える場合には、カーボンブラック微粒子粉末の粒子サイズが大きいため、ポリシロキサン被覆へ均一に付着させるために非常に大きな機械的せん断力が必要となり、工業的に不利となる。
【００７８】
カーボンブラック微粒子粉末は、少量ずつを時間をかけながら、殊に５〜６０分程度をかけて添加するのが好ましい。
【００７９】
混合攪拌時における条件は、カーボンブラックがポリシロキサン被覆に均一に付着するように、線荷重は１９．６〜１９６０Ｎ／ｃｍ（２〜２００Ｋｇ／ｃｍ）、好ましくは９８〜１４７０Ｎ／ｃｍ（１０〜１５０Ｋｇ／ｃｍ）、より好ましくは１４７〜９８０Ｎ／ｃｍ（１５〜１００Ｋｇ／ｃｍ）、処理時間は５〜１２０分、好ましくは１０〜９０分の範囲で処理条件を適宜調整すればよい。なお、撹拌速度は２〜２０００ｒｐｍ、好ましくは５〜１０００ｒｐｍ、より好ましくは１０〜８００ｒｐｍの範囲で処理条件を適宜調整すればよい。
【００８０】
カーボンブラック微粒子粉末の添加量は、黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末１００重量部に対して１〜３０重量部である。１重量部未満の場合には、カーボンブラックの付着量が不十分であり、十分な黒色度を有する鉄系黒色複合顔料が得られない。３０重量部を超える場合には、得られる鉄系黒色複合顔料は十分な黒色度を有しているが、カーボンブラックの付着量が多くなるため粒子表面からカーボンブラックが脱離しやすくなり、その結果、ビヒクル中や樹脂組成物中への分散性が低下する。
【００８１】
乾燥を行う場合の加熱温度は、通常４０〜２００℃が好ましく、より好ましくは６０〜１５０℃であり、加熱時間は、１０分〜１２時間が好ましく、３０分〜３時間がより好ましい。
【００８２】
黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末は、必要により、ポリシロキサンとの混合攪拌に先立って、あらかじめ、粒子表面をアルミニウムの水酸化物、アルミニウムの酸化物、ケイ素の水酸化物及びケイ素の酸化物から選ばれる１種又は２種以上で被覆しておいてもよい。
【００８３】
アルミニウムの水酸化物等による被覆は、黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末を分散して得られる水懸濁液に、アルミニウム化合物、ケイ素化合物又は当該両化合物を添加して混合攪拌することにより、又は、必要により、混合攪拌後にｐＨ値を調整することにより、前記黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末の粒子表面に、アルミニウムの水酸化物、アルミニウムの酸化物、ケイ素の水酸化物及びケイ素の酸化物から選ばれる１種又は２種以上を被着し、次いで、濾別、水洗、乾燥、粉砕する。必要により、更に、脱気・圧密処理等を施してもよい。
【００８４】
アルミニウム化合物としては、酢酸アルミニウム、硫酸アルミニウム、塩化アルミニウム、硝酸アルミニウム等のアルミニウム塩やアルミン酸ナトリウム等のアルミン酸アルカリ塩等が使用できる。
【００８５】
アルミニウム化合物の添加量は、黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末に対してＡｌ換算で０．０１〜５０重量％である。０．０１重量％未満である場合には、鉄系黒色複合顔料のビヒクル中や樹脂組成物中への分散性改良効果が得られるだけの十分な量のアルミニウムの水酸化物等を粒子表面に被覆することが困難である。５０重量％を超える場合には、被覆効果が飽和するため必要以上に添加する意味がない。
【００８６】
ケイ素化合物としては、３号水ガラス、オルトケイ酸ナトリウム、メタケイ酸ナトリウム、コロイダルシリカ等が使用できる。
【００８７】
ケイ素化合物の添加量は、黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末に対してＳｉＯ₂換算で０．０１〜５０重量％である。０．０１重量％未満である場合には、鉄系黒色複合顔料のビヒクル中や樹脂組成物中への分散性改良効果が得られるだけの十分な量のケイ素の酸化物等を粒子表面に被覆することが困難である。５０重量％を超える場合には、被覆効果が飽和するため、必要以上に添加する意味がない。
【００８８】
アルミニウム化合物とケイ素化合物とを併せて使用する場合には、黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末に対し、Ａｌ換算量とＳｉＯ₂換算量との総和で０．０１〜５０重量％が好ましい。
【００８９】
次に、本発明に係る塗料について述べる。
【００９０】
本発明に係る塗料は、溶剤系塗料を用いて塗膜を形成した場合、塗膜中に存在するカーボンブラック量が少ないにもかかわらず、Ｌ^*値が１５．０〜１９．０、好ましくは１５．０〜１８．５、より好ましくは１５．０〜１８．０であり、カーボンブラック微粒子粉末のみを使用した塗料を用いて形成した塗膜の黒色度に比べて同等又は遜色のない黒色度を有している。また、光沢度は８５％以上、好ましくは８７％以上、より好ましくは８８％以上であって、耐酸性はΔＧ値が１０．０以下、好ましくは９．５以下、より好ましくは９．０以下であって、ΔＬ^*値が１．０以下、好ましくは０．９以下、より好ましくは０．８以下である。
【００９１】
本発明に係る塗料は、水系塗料を用いて塗膜を形成した場合、塗膜中に存在するカーボンブラック量が少ないにもかかわらず、Ｌ^*値が１５．０〜１９．５、好ましくは１５．０〜１９．０、より好ましくは１５．０〜１８．５であり、カーボンブラック微粒子粉末のみを使用した塗料を用いて形成した塗膜の黒色度に比べて同等又は遜色のない黒色度を有している。また、光沢度は、８０％以上、好ましくは８３％以上、より好ましくは８５％以上であって、耐酸性はΔＧ値が１０．０以下、好ましくは９．５以下、より好ましくは９．０以下であって、ΔＬ^*値が１．０以下、好ましくは０．９以下、より好ましくは０．８以下である。
【００９２】
本発明に係る塗料中に配合されている鉄系黒色複合顔料は、塗料構成基材１００重量部に対して１．０〜１００重量部である。塗料のハンドリングを考慮すれば、好ましくは２．０〜１００重量部、更に好ましくは５．０〜１００重量部である。
【００９３】
上記塗料構成基材としては、樹脂及び溶剤とともに、必要により消泡剤、体質顔料、乾燥促進剤、界面活性剤、硬化促進剤、助剤等である。
【００９４】
溶剤系塗料の場合の樹脂は、通常使用されているアクリル樹脂、アルキッド樹脂、ポリエステル樹脂、ポリウレタン樹脂、エポキシ樹脂、フェノール樹脂、メラミン樹脂、アミノ樹脂等である。
【００９５】
水系塗料の場合の樹脂は、通常使用されている水溶性アルキッド樹脂、水溶性メラミン樹脂、水溶性アクリル樹脂、水溶性ウレタンエマルジョン樹脂等である。
【００９６】
溶剤系塗料の溶剤は、通常使用されているトルエン、キシレン、ブチルアセテート、メチルアセテート、メチルイソブチルケトン、ブチルセロソルブ、エチルセロソルブ、ブチルアルコール、脂肪族炭化水素等である。
【００９７】
水系塗料の溶剤は、水に加えて水系塗料で通常使用されているブチルセロソルブ、ブチルアルコール等である。
【００９８】
消泡剤は、ノプコ８０３４（商品名）、ＳＮデフォーマー４７７（商品名）、ＳＮデフォーマー５０１３（商品名）、ＳＮデフォーマー２４７（商品名）、ＳＮデフォーマー３８２（商品名）（以上、いずれもサンノプコ株式会社製）、アンチホーム０８（商品名）、エマルゲン９０３（商品名）（以上、いずれも花王株式会社製）等である。
【００９９】
次に、本発明に係るゴム・樹脂組成物について述べる。
【０１００】
本発明に係るゴム・樹脂組成物は、ゴム・樹脂組成物中に存在するカーボンブラック量が少ないにもかかわらず、Ｌ^*値が１５．０〜２１．０、好ましくは１５．０〜２０．５、より好ましくは１５．０〜２０．０であり、カーボンブラック微粒子粉末のみを使用したゴム・樹脂組成物の黒色度に比べて同等又は遜色のない黒色度を有している。また、ゴム・樹脂組成物中での分散性は、目視観察より、４又は５が好ましく、より好ましくは５である。耐老化性は、１９０℃で９０分間加熱した際の変色部分の割合が１５％以下、好ましくは１０％以下、より好ましくは５％以下である。
【０１０１】
本発明に係るゴム・樹脂組成物中に配合されている鉄系黒色複合顔料は、構成基材１００重量部に対して０．５〜２００重量部の範囲であり、ゴム・樹脂組成物のハンドリングを考慮すれば、好ましくは１．０〜１５０重量部、更に好ましくは２．５〜１００重量部である。
【０１０２】
上記ゴム・樹脂組成物の構成基材は、ゴム又は周知の熱可塑性樹脂とともに、必要により、滑剤、可塑剤、酸化防止剤、紫外線吸収剤、各種安定剤等の添加剤である。
【０１０３】
添加剤は、鉄系黒色複合顔料とゴム又は樹脂との総和に対して５０重量％以下であればよい。添加剤の含有量が５０重量％を超える場合には、成形性が低下する。
【０１０４】
本発明に係るゴム・樹脂組成物は、ゴム又は樹脂原料と鉄系黒色複合顔料をあらかじめよく混合し、次に、混練機もしくは押出機を用いて加熱下で強いせん断作用を加えて、鉄系黒色複合顔料の凝集体を破壊し、ゴム又は樹脂中に鉄系黒色複合粒子粉末を均一に分散させた後、目的に応じた形状に成形加工して使用する。
【０１０５】
【発明の実施の形態】
本発明の代表的な実施の形態は、次の通りである。
【０１０６】
黒色酸化鉄粒子粉末、黒色含水酸化鉄粒子粉末、カーボンブラック微粒子粉末及び鉄系黒色複合顔料の各粒子粉末の平均粒子径は、電子顕微鏡写真（×２００００）を縦方向及び横方向にそれぞれ４倍に拡大した写真に示される粒子約３５０個について定方向径をそれぞれ測定し、その平均値で示した。
【０１０７】
球形度は、平均最長径と平均最短径との比で示し、軸比は、平均長軸径と平均短軸径との比で示し、板状比は平均板面径と平均厚みとの比で示した。
【０１０８】
粒子径（長軸径）の幾何標準偏差値は、下記の方法により求めた値で示した。即ち、上記拡大写真に示される粒子径を測定した値を、その測定値から計算して求めた粒子の実際の粒子径と個数から、統計学的手法に従って、対数正規確率紙上の横軸に粒子径を、縦軸に所定の粒子径区間のそれぞれに属する粒子の累積個数( 積算フルイ下) を百分率でプロットした。そしてこのグラフから粒子の累積個数が５０％及び８４．１３％のそれぞれに相当する粒子径の値を読み取り、幾何標準偏差値＝（積算フルイ下８４．１３％における粒子径）／（積算フルイ下５０％における粒子径（幾何平均径）に従って算出した値で示した。幾何標準偏差値が１に近いほど、粒子径（長軸径）粒度分布が優れていることを意味する。
【０１０９】
比表面積値は、ＢＥＴ法により測定した値で示した。
【０１１０】
黒色酸化鉄粒子粉末、黒色含水酸化鉄粒子粉末及び鉄系黒色複合顔料の粒子内部や粒子表面に存在するＭｎ量、Ａｌ量、及びＳｉ量並びに鉄系黒色複合顔料に被覆されているポリシロキサンに含有されるＳｉ量のそれぞれは、「蛍光Ｘ線分析装置３０６３Ｍ型」（理学電機工業（株) 製）を使用し、ＪＩＳ Ｋ０１１９の「けい光Ｘ線分析通則」に従って測定した。
【０１１１】
鉄系黒色複合顔料に付着しているカーボンブラックの量は「堀場金属炭素・硫黄分析装置ＥＭＩＡ−２２００型」（（株) 堀場製作所製）を用いて炭素量を測定することにより求めた。
【０１１２】
鉄系黒色複合顔料に付着しているカーボンブラックの付着厚みは、「透過型電子顕微鏡ＪＥＭ−２０１０」（日本電子株式会社（製））を用いて加速電圧２００ｋＶの条件下で撮影した電子顕微鏡写真を１０倍に拡大した写真（×５，０００，０００）に写っている粒子の表面に付着しているカーボンブラックの平均的な厚み部分を測定することにより求めた。
【０１１３】
鉄系黒色複合顔料に付着しているカーボンブラックの脱離率（％）は、下記の方法により求めた値で示した。カーボンブラックの脱離率が０％に近いほど、粒子表面からのカーボンブラックの脱離量が少ないことを示す。
【０１１４】
鉄系黒色複合顔料３ｇとエタノール４０ｍｌを５０ｍｌの沈降管に入れ、２０分間超音波分散を行った後、１２０分静置し、比重差によって鉄系黒色複合顔料と脱離したカーボンブラックを分離した。次いで、この鉄系黒色複合顔料に再度エタノール４０ｍｌを加え、更に２０分間超音波分散を行った後１２０分静置し、鉄系黒色複合顔料と脱離したカーボンブラックを分離した。この鉄系黒色複合顔料を１００℃で１時間乾燥させ、前述の「堀場金属炭素・硫黄分析装置ＥＭＩＡ−２２００型」（株式会社堀場製作所製）を用いて炭素量を測定し、下記式に従って求めた値をカーボンブラックの脱離率とした。
【０１１５】
カーボンブラックの脱離率（％）＝[（Ｗａ−Ｗｅ）／Ｗａ]×１００
Ｗａ：鉄系黒色複合顔料のカーボンブラック付着量
Ｗｅ：脱離テスト後の鉄系黒色複合顔料のカーボンブラック付着量
【０１１６】
黒色酸化鉄粒子粉末、黒色含水酸化鉄粒子粉末及び鉄系黒色複合顔料のそれぞれの黒色度は、試料０．５ｇとヒマシ油０．７ｍｌとをフーバー式マーラーで練ってペースト状とし、このペーストにクリアラッカー４．５ｇを加え、混練、塗料化してキャストコート紙上に１５０μｍ（６ｍｉｌ）のアプリケーターを用いて塗布した塗布片（塗膜厚み：約３０μｍ）を作製し、 該塗料片について、多光源分光測色計ＭＳＣ−ＩＳ−２Ｄ（スガ試験機（株）製）を用いて測定を行い、ＪＩＳ Ｚ ８７２９に定めるところに従って表色指数Ｌ^*値で示した。
【０１１７】
塗料の黒色度は、後述組成の塗料を塗布して得られた塗布膜の黒色度を、ゴム・樹脂組成物の黒色度は、後述組成からなる樹脂プレートの黒色度を、それぞれ多光源分光測色計ＭＳＣ−ＩＳ−２Ｄ（スガ試験機（株）製）を用いて測定を行い、ＪＩＳ Ｚ ８７２９に定めるところに従って表色指数Ｌ^*値で示した。
【０１１８】
ここでＬ^*値は、明度を表わし、Ｌ^*値が小さいほど黒色度が優れていることを示す。
【０１１９】
塗料ビヒクル中への分散性は、発明の実施の形態と同様にして作製した塗膜の光沢度を測定することにより評価を行った。
【０１２０】
光沢度は、「グロスメーター ＵＧＶ−５Ｄ」（スガ試験機（株）製）を用いて２０°光沢度を測定して求めた。光沢度が高いほど、粒子粉末の塗料ビヒクル中への分散性が良いことを示す。
【０１２１】
塗料粘度については、後述の処方によって調製した塗料の２５℃における塗料粘度をＥ型粘度計（コーンプレート型粘度計）ＥＭＤ−Ｒ（（株）東京計器製）を用いて、ずり速度Ｄ＝１．９２ｓｅｃ^-1における値を求めた。
【０１２２】
樹脂組成物中への分散性は、 得られた樹脂組成物表面における未分散の凝集粒子の個数を目視により判定し、５段階で評価した。５が最も分散状態が良いことを示す。
【０１２３】
１： １ｃｍ²当たりに５０個以上
２： １ｃｍ²当たりに１０個以上５０個未満
３： １ｃｍ²当たりに５個以上１０個未満
４： １ｃｍ²当たりに１個以上５個未満
５： 未分散物認められず
【０１２４】
耐酸性は、下記のようにして求めた。
【０１２５】
黒色顔料を用いて得られた塗料を冷間圧延鋼板（０．８ｍｍ×７０ｍｍ×１５０ｍｍ）（ＪＩＳ Ｇ ３１４１）に１５０μｍの厚みで塗布、乾燥して製造した塗膜を有する試料片を用意し、光沢度及び黒色度を測定した。
【０１２６】
次に、１０００ｍｌのビーカーに５重量％硫酸水溶液を入れ、上記試料片を糸でつるして、約１２０ｍｍの深さまで浸し２５℃で２４時間静置した。
【０１２７】
次に、試料片を酸液から取り出して流水で静かに洗い、水を振り切った後、試料片の中心部分の光沢度及び黒色度を測定した。そして、試料片の酸液への浸漬前後の光沢度変化（ΔＧ）、及び黒色度変化（ΔＬ^*値）を測定し、これの大小で耐酸性を評価した。ΔＧ及びΔＬ^*値がともに小さいほど耐酸性に優れていることを示す。
【０１２８】
耐老化性は、黒色顔料を練り込んだ着色樹脂プレート（縦１．５ｃｍ×横１．５ｃｍ×厚み１ｍｍ）を１９０℃で加熱したときに、変色して樹脂が劣化した部分の面積Ｓと加熱前の着色プレートの表面積Ｓ₀（１．５×１．５＝２．２５ｃｍ²）との比Ｓ／Ｓ₀を５％刻みで定量することにより求めた。
【０１２９】
即ち、（Ｓ／Ｓ₀）×１００が０％のときは劣化が無い状態を示し、（Ｓ／Ｓ₀）×１００が１００％のときは樹脂が完全に劣化した状態を示す。
【０１３０】
＜鉄系黒色複合顔料の製造＞
図１の電子顕微鏡写真（×２００００）に示すマンガン含有黒色ヘマタイト粒子粉末（粒子形状：粒状、球形度１．３、平均粒子径０．３０μｍ、幾何標準偏差値１．４６、ＢＥＴ比表面積値３．６ｍ²／ｇ、Ｍｎ含有量１３．３重量％、黒色度Ｌ^*値２２．６）２０ｋｇを、凝集を解きほぐすために、純水１５０ｌに攪拌機を用いて邂逅し、更に、「ＴＫパイプラインホモミクサー」（製品名、特殊機化工業（株) 製）を３回通してマンガン含有黒色ヘマタイト粒子粉末を含むスラリーを得た。
【０１３１】
続いて、このマンガン含有黒色ヘマタイト粒子粉末を含むスラリーを横形サンドグラインダー「マイティーミルＭＨＧ−１．５Ｌ」（製品名、井上製作所（株) 製）を用いて、軸回転数２０００ｒｐｍにおいて５回パスさせて、マンガン含有黒色ヘマタイト粒子粉末を含む分散スラリーを得た。
【０１３２】
得られたマンガン含有黒色ヘマタイト粒子粉末を含む分散スラリーの３２５ｍｅｓｈ（目開き４４μｍ）における篩残分は０％であった。この分散スラリーを濾別、水洗して、マンガン含有黒色ヘマタイト粒子粉末のケーキを得た。このマンガン含有黒色ヘマタイト粒子粉末のケーキを１２０℃で乾燥した後、乾燥粉末１１．０ｋｇをエッジランナー「ＭＰＵＶ−２型」（製品名、（株）松本鋳造鉄工所製）に投入して、２９４Ｎ／ｃｍ（３０Ｋｇ／ｃｍ）で３０分間攪拌を行い、粒子粉末の凝集を軽く解きほぐした。
【０１３３】
次に、メチルハイドロジェンポリシロキサン（商品名：ＴＳＦ４８４：東芝シリコーン（株）製）１１０ｇを、エッジランナーを稼動させながら粒子の凝集を解きほぐした上記マンガン含有黒色ヘマタイト粒子粉末に添加し、５８８Ｎ／ｃｍ（６０Ｋｇ／ｃｍ）の線荷重で６０分間混合攪拌を行った。なお、この時の攪拌速度は２２ｒｐｍで行った。
【０１３４】
次に、図２の電子顕微鏡写真（×２００００）に示すカーボンブラック微粒子粉末（粒子形状：粒状、粒子径０．０２２μｍ、幾何標準偏差値１．６８、ＢＥＴ比表面積値１３４ｍ²／ｇ、黒色度Ｌ^*値１６．６）５５０ｇを、エッジランナーを稼動させながら１０分間かけて添加し、更に５８８Ｎ／ｃｍ（６０Ｋｇ／ｃｍ）の線荷重で６０分間混合攪拌を行い、メチルハイドロジェンポリシロキサン被覆にカーボンブラックを付着させた後、乾燥機を用いて１０５℃で６０分間乾燥を行い、鉄系黒色複合顔料を得た。なお、この時の攪拌速度は２２ｒｐｍで行った。
【０１３５】
得られた鉄系黒色複合顔料は、図３の電子顕微鏡写真（×２００００）に示す通り、粒子径が０．３１μｍ、球形度が１．３の粒状粒子であった。幾何標準偏差値は１．４６であり、ＢＥＴ比表面積値は８．９ｍ²／ｇ、Ｍｎ含有量は１２．６重量％、黒色度Ｌ^*値は１８．２、カーボンブラック脱離率は６．４％であり、メチルハイドロジェンポリシロキサンの被覆量はＳｉ換算で０．４１重量％であった。付着しているカーボンブラック量はＣ換算で４．７６重量％（マンガン含有黒色ヘマタイト粒子粉末１００重量部に対して５重量部に相当する）、粒子表面のカーボンブラックの付着厚みは０．００２３μｍであった。図３に示す電子顕微鏡写真には、カーボンブラックがほとんど認められないことから、カーボンブラックのほぼ全量がメチルハイドロジェンポリシロキサン被覆に付着していることが認められた。
【０１３６】
比較のため、メチルハイドロジェンポリシロキサンを被覆することなく、マンガン含有黒色ヘマタイト粒子粉末とカーボンブラック微粒子粉末とを同様にエッジランナーで混合攪拌して得られた混合粒子粉末の電子顕微鏡写真（×２００００）を図４に示す。図４の電子顕微鏡写真に示される通り、カーボンブラックがマンガン含有黒色ヘマタイト粒子の粒子表面に付着しておらず、両粒子粉末が別々に混在していることが認められた。
【０１３７】
＜溶剤系塗料の製造＞
上記鉄系黒色複合顔料１０ｇとアミノアルキッド樹脂及びシンナーとを下記割合で配合して３ｍｍφガラスビーズ９０ｇとともに１４０ｍｌのガラスビンに添加し、次いで、ペイントシェーカーで９０分間混合分散し、ミルベースを作製した。
【０１３８】
鉄系黒色複合顔料 １２．２重量部
アミノアルキッド樹脂 １９．５重量部
（アミラックＮｏ．１０２６：関西ペイント（株）製）
シンナー ７．３重量部
【０１３９】
上記ミルベースを用いて、下記割合となるようにアミノアルキッド樹脂を配合してペイントシェーカーで更に１５分間混合分散して、鉄系黒色複合顔料を含む塗料を得た。
【０１４０】
ミルベース ３９．０重量部
アミノアルキッド樹脂 ６１．０重量部
（アミラックＮｏ．１０２６：関西ペイント（株）製）
【０１４１】
得られた溶剤系塗料の塗料粘度は７０２ｃＰであった。
【０１４２】
この塗料を用いて製造した塗膜の光沢度は９１％、塗膜の黒色度Ｌ^*値は１８．６であった。塗膜の耐酸性テストに基づく光沢度変化ΔＧ値は６．１％、明度変化ΔＬ^*値は０．７であった。
【０１４３】
＜水系塗料の製造＞
上記鉄系黒色複合顔料７．６２ｇと水溶性アルキド樹脂等とを下記割合で３ｍｍφガラスビーズ９０ｇとともに１４０ｍｌのガラスビンに添加し、次いでペイントシェーカーで４５分間又は９０分間混合分散し、ミルベースを作製した。
【０１４４】
鉄系黒色複合顔料 １２．４重量部
水溶性アルキド樹脂 ９．０重量部
（商品名：Ｓ−１１８：大日本インキ化学工業（株）製）
消泡剤 ４．８重量部
（商品名：ノプコ８０３４：サンノプコ（株）製）
水 ４．８重量部
ブチルセロソルブ ４．１重量部
【０１４５】
上記ミルベースを用いて、塗料組成を下記割合で配合してペイントシェーカーで更に１５分間混合分散し水系塗料を得た。
【０１４６】
ミルベース ３０．４重量部
水溶性アルキッド樹脂 ４６．２重量部
（商品名：Ｓ−１１８：大日本インキ化学工業（株）製）
水溶性メラミン樹脂 １２．６重量部
（商品名：Ｓ−６９５：大日本インキ化学工業（株）製）
消泡剤 ０．１重量部
（商品名：ノプコ８０３４：サンノプコ（株）製）
水 ９．１重量部
ブチルセロソルブ １．６重量部
【０１４７】
得られた水系塗料の塗料粘度は７９８ｃＰであった。
【０１４８】
この塗料を用いて製造した塗膜の光沢度は８６％、塗膜の黒色度Ｌ^*値は１８．８であった。塗膜の耐酸性テストに基づく光沢度変化ΔＧ値は、５．３％、明度変化ΔＬ^*値は０．７であった。
【０１４９】
＜樹脂組成物の製造＞
前記鉄系黒色複合顔料２．５ｇとポリ塩化ビニル樹脂粉末１０３ＥＰ８Ｄ（日本ゼオン（株）製）４７．５ｇとを秤量し、これらを１００ｍｌポリビーカーに入れ、スパチュラでよく混合して混合粉末を得た。
【０１５０】
得られた混合粉末にステアリン酸カルシウムを０．５ｇ加えて混合し、１６０℃に加熱した熱間ロールのクリアランスを０．２ｍｍに設定した後、上記混合粉末を少しずつロールにて練り込んで樹脂組成物が一体となるまで混練を続けた後、樹脂組成物をロールから剥離して着色樹脂プレート原料として用いた。
【０１５１】
次に、表面研磨されたステンレス板の間に上記樹脂組成物を挟んで１８０℃に加熱したホットプレス内に入れ、９８０００ｋＰａ（１トン／ｃｍ²）の圧力で加圧成形して厚さ１ｍｍの着色樹脂プレートを得た。得られた着色樹脂プレートの黒色度Ｌ^*値は１７．９、分散状態は５であった。
【０１５２】
着色樹脂プレートを１．５ｃｍ角に裁断した試験片３枚を１９０℃に加熱されたギヤオーブン中に入れ、３０分毎に１枚ずつ取り出し、樹脂劣化の状態を調べた所、３０分後の樹脂劣化程度（Ｓ／Ｓ₀×１００）は０％、６０分後の樹脂劣化程度は０％、９０分後の樹脂劣化程度は５％であった。
【０１５３】
【作用】
本発明において最も重要な点は、黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末、必要により、該黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末の粒子表面にアルミニウムの水酸化物、アルミニウムの酸化物、ケイ素の水酸化物及びケイ素の酸化物から選ばれた１種又は２種以上の化合物が被覆されている黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末の粒子表面にポリシロキサンが被覆されており、該ポリシロキサン被覆の少なくとも１部にカーボンブラックが付着している平均粒子径０．０８２〜１．０５μｍの鉄系黒色複合粒子粉末であって、上記カーボンブラックの付着量が前記黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末１００重量部に対して１〜３０重量部である鉄系黒色複合顔料は、粒子表面から脱離するカーボンブラックが少ないことにより、ビヒクル中や樹脂組成物中への分散性に優れており、且つ、少ないカーボンブラック量で、カーボンブラック微粒子粉末のみを使用した場合の黒色度に比べて同等又は遜色のない黒色度が得られるという事実である。
【０１５４】
本発明に係る鉄系黒色複合顔料の粒子表面から脱離するカーボンブラックが少ない理由について、本発明者は、カーボンブラックが付着しているポリシロキサンが有している各種官能基が、黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末の粒子表面へ強固に結合するためと考えている。
【０１５５】
本発明に係る鉄系黒色複合顔料のビヒクル中や樹脂組成物中における分散性が優れている理由について、本発明者は、鉄系黒色複合顔料の粒子表面から脱離するカーボンブラックが少ないことに起因して、カーボンブラックによって系内の分散が阻害されないとともに、鉄系黒色複合顔料の粒子表面にカーボンブラックが付着していることにより粒子表面に凹凸が生じ、粒子相互間の接触が抑制されるためと考えている。
【０１５６】
本発明に係る鉄系黒色複合顔料の黒色度が優れている理由について、本発明者は、微粒子であることに起因して、通常は凝集体として挙動するカーボンブラックが、黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末の粒子表面にポリシロキサンを介して均一且つ緻密に付着されているため、カーボンブラックによって芯粒子の色が打ち消され、カーボンブラック本来の色が発揮されたことによるものと考えている。
【０１５７】
そして、上記鉄系黒色複合顔料を配合した塗料を用いて形成された塗膜は耐酸性が優れており、また、上記鉄系黒色複合顔料を配合して得られた樹脂組成物は耐老化性が優れているという事実である。
【０１５８】
本発明に係る塗料を用いて形成された塗膜の耐酸性及び樹脂組成物の耐老化性が優れている理由について、本発明者は、耐酸性や耐老化性に優れているカーボンブラックを、黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末の粒子表面にポリシロキサンを介して付着させたことにより、黒色酸化鉄粒子粉末又は黒色含水酸化鉄粒子粉末が本来有している酸化しやすく表面活性が高いという特性が打ち消され、カーボンブラック本来の特性が発揮されたことによるものと考えている。
【０１５９】
【実施例】
次に、実施例並びに比較例を挙げる。
【０１６０】
芯粒子１〜７
公知の製造方法で得られた各種の黒色酸化鉄粒子粉末及び黒色含水酸化鉄粒子粉末を準備し、上記発明の実施の形態と同様にして凝集が解きほぐされた黒色酸化鉄粒子粉末及び黒色含水酸化鉄粒子粉末を得た。
【０１６１】
これら黒色酸化鉄粒子粉末及び黒色含水酸化鉄粒子粉末の諸特性を表１に示す。
【０１６２】
【表１】

【０１６３】
芯粒子８
芯粒子１の凝集が解きほぐされた粒状マンガン含有黒色ヘマタイト粒子粉末２０ｋｇと水１５０ｌとを用いて、発明の実施の形態と同様にして粒状マンガン含有黒色ヘマタイト粒子粉末を含むスラリーを得た。得られた粒状マンガン含有黒色ヘマタイト粒子粉末を含む再分散スラリーのｐＨ値を水酸化ナトリウム水溶液を用いて１０．５に調整し、次いで、該スラリーに水を加えスラリー濃度を９８ｇ／ｌに調整した。このスラリー１５０ｌを加熱して６０℃とし、このスラリー中に１．０ｍｏｌ／ｌのアルミン酸ナトリウム溶液２７２２ｍｌ（粒状マンガン含有黒色ヘマタイト粒子粉末に対してＡｌ換算で０．５重量％に相当する）を加え、３０分間保持した後、酢酸を用いてｐＨ値を７．５に調整した。この状態で３０分間保持した後、濾過、水洗、乾燥、粉砕して粒子表面がアルミニウムの水酸化物により被覆されている粒状マンガン含有黒色ヘマタイト粒子粉末を得た。
【０１６４】
この時の主要製造条件を表２に、得られた粒子表面がアルミニウムの水酸化物により被覆されている粒状マンガン含有黒色ヘマタイト粒子粉末の諸特性を表３に示す。
【０１６５】
尚、表面処理工程における被覆物の種類のＡはアルミニウムの水酸化物を表わし、Ｓはケイ素の酸化物を表わす。
【０１６６】
芯粒子９〜１４
芯粒子の種類、表面処理工程における添加物の種類及び添加量を種々変えた以外は芯粒子８と同様にして表面処理済芯粒子粉末を得た。
【０１６７】
この時の主要処理条件を表２に、得られた表面処理済芯粒子粉末の諸特性を表３に示す。
【０１６８】
【表２】

【０１６９】
【表３】

【０１７０】
実施例１〜４２、比較例１〜１１
芯粒子の種類、ポリシロキサン被覆工程におけるポリシロキサン添加の有無、種類及び添加量、エッジランナー処理条件、カーボンブラックの付着工程におけるカーボンブラック微粒子粉末の種類及び添加量、エッジランナーによる処理条件を種々変えた以外は、前記発明の実施の形態と同様にして鉄系黒色複合顔料を得た。実施例１〜４２の各実施例で得られた鉄系黒色複合顔料は、電子顕微鏡観察の結果、カーボンブラックがほとんど認められないことから、カーボンブラックのほぼ全量がポリシロキサン被覆に付着していることが認められた。
【０１７１】
使用したカーボンブラック微粒子粉末Ａ乃至Ｃの諸特性を表４に示す。
【０１７２】
【表４】

【０１７３】
この時の主要処理条件及び得られた鉄系黒色複合顔料の諸特性を表５乃至表１０に示す。
【０１７４】
【表５】

【０１７５】
【表６】

【０１７６】
【表７】

【０１７７】
【表８】

【０１７８】
【表９】

【０１７９】
【表１０】

【０１８０】
比較例１２（特公昭５０−１３３００号記載の方法）
芯粒子３のマグネタイト粒子粉末（ブラック酸化鉄）を含む水懸濁液（マグネタイト粒子粉末６８．３ｇを含有する懸濁液１０００ｍｌ）を調整し、冷水で５回洗浄した。
【０１８１】
次に、カーボンブラック微粒子粉末Ｂの水性分散液（乾燥カーボンブラックＢ１．７５ｇを含有する５ｇの水分散液）を冷水で５００ｍｌに希釈した。
【０１８２】
このカーボンブラック微粒子粉末の懸濁液を攪拌しながら、上記マグネタイト粒子粉末を含む水懸濁液に５分間に亘って添加し、添加完了後、混合懸濁液を更に１０分間に亘って攪拌を続け、次いで放置した。
【０１８３】
約４時間後、得られた黒色沈殿物を常法により、水で濾別洗浄を５回繰り返した後、１００℃で空気中で乾燥した。
【０１８４】
得られた黒色粒子粉末のカーボンブラック脱離率は５０．２％、黒色度Ｌ^*値は２０．２であり、芯粒子粉末であるマグネタイト粒子粉末の黒色度とほとんど変わらない値であった。
【０１８５】
＜溶剤系塗料の製造＞
実施例４３〜８４、比較例１３〜３３
黒色顔料の種類を種々変えた以外は、前記発明の実施の形態と同様にして溶剤系塗料を製造した。
【０１８６】
この時の主要製造条件及び得られた塗膜の諸特性を表１１乃至表１３に示した。
【０１８７】
【表１１】

【０１８８】
【表１２】

【０１８９】
【表１３】

【０１９０】
＜水系塗料の製造＞
実施例８５〜１２６、比較例３４〜５４
黒色顔料の種類を種々変えた以外は、前記発明の実施の形態と同様にして水系塗料を製造した。
【０１９１】
この時の主要製造条件及び得られた塗膜の諸特性を表１４乃至表１６に示した。
【０１９２】
【表１４】

【０１９３】
【表１５】

【０１９４】
【表１６】

【０１９５】
＜樹脂組成物の製造＞
実施例１２７〜１６８、比較例５５〜７５
黒色顔料の種類を種々変えた以外は、前記発明の実施の形態と同様にして着色樹脂プレートを製造した。
【０１９６】
この時の主要製造条件及び得られた着色樹脂プレートの諸特性を表１７乃至１９に示す。
【０１９７】
【表１７】

【０１９８】
【表１８】

【０１９９】
【表１９】

【０２００】
【発明の効果】
本発明に係る鉄系黒色複合顔料は、粒子表面から脱離するカーボンブラックが少ないことにより、ビヒクル中や樹脂組成物中における分散性に優れており、且つ、少ないカーボンブラック量で、カーボンブラック微粒子粉末のみを使用した場合の黒色度に比べて同等又は遜色のない黒色度を有しているので、塗料用、印刷インク用、化粧品用、ゴム・樹脂成形物用等の黒色顔料として好ましいものである。
【０２０１】
上記鉄系黒色複合顔料を用いて得られる本発明に係る塗料は、これを用いて塗膜を形成した場合、少ないカーボンブラック量で、カーボンブラック微粒子粉末のみを使用した塗料を用いて形成した塗膜の黒色度に比べて同等又は遜色のない黒色度を有しているとともに、得られた塗膜の耐酸性が優れているので、黒色塗料として好適である。
【０２０２】
上記鉄系黒色複合顔料を用いて得られる本発明に係るゴム・樹脂組成物は、少ないカーボンブラック量で、カーボンブラック微粒子粉末のみを使用した場合のゴム・樹脂組成物の黒色度に比べて同等又は遜色のない黒色度を有しているとともに、耐酸性が優れているので、黒色のゴム・樹脂組成物として好ましいものである。
【０２０３】
そして、本発明に係る鉄系黒色複合顔料は、ビヒクル中や樹脂組成物中への分散性が優れており、取り扱いやすく作業性に優れているので、工業的及び経済的に有利である。
【０２０４】
また、カーボンブラック微粒子粉末の使用量が少ないので、安全上、衛生上からも好ましいものである。
【図面の簡単な説明】
【図１】 発明の実施の形態で使用した粒状マンガン含有黒色ヘマタイト粒子粉末の粒子構造を示す電子顕微鏡写真（×２００００）である。
【図２】 発明の実施の形態で使用したカーボンブラック微粒子粉末の粒子構造を示す電子顕微鏡写真（×２００００）である。
【図３】 発明の実施の形態で得られた鉄系黒色複合顔料の粒子構造を示す電子顕微鏡写真（×２００００）である。
【図４】 比較のために示したマンガン含有黒色ヘマタイト粒子粉末とカーボンブラック微粒子粉末との混合粒子粉末の粒子構造を示す電子顕微鏡写真（×２００００）である。[0001]
[Industrial application fields]
The present invention is excellent in dispersibility in a vehicle or a resin composition due to a small amount of carbon black desorbed from the particle surface, and when only a carbon black fine particle powder is used with a small amount of carbon black. In addition to providing an iron-based black composite pigment having a blackness comparable or comparable to the blackness of the paint, a paint that forms a coating film excellent in acid resistance and a resin composition excellent in aging resistance The purpose is to provide.
[0002]
[Prior art]
Carbon black fine particle powder and magnetite particle powder are typical black pigments, and have been widely used as colorants for paints, printing inks, cosmetics, rubber / resin compositions, etc. for a long time.
[0003]
The carbon black fine particle powder has the highest blackness among various black pigments, and the coating film and resin composition obtained using the carbon black fine particle powder are also excellent in acid resistance and aging resistance. On the other hand, since the carbon black fine particle powder is a fine particle powder having an average particle size of about 0.005 to 0.05 μm, it is difficult to disperse in the vehicle or the resin composition, and the bulk density is 0.00. 1g / cm ^Three Since the powder is bulky and bulky, handling is difficult and workability is poor. In addition, problems from safety and hygiene such as carcinogenicity have been pointed out.
[0004]
In other words, the carbon black fine particle powder tends to have better blackness as the amount used becomes larger, but if the amount used is increased, the dispersion in the vehicle or the resin composition becomes more difficult and the workability becomes worse. Also, it is not preferable from the viewpoint of safety and hygiene.
[0005]
On the other hand, the magnetite particle powder has an appropriate particle size, particularly an average particle diameter of about 0.08 to 1.0 μm, compared with the carbon black fine particle powder, and therefore dispersibility in the vehicle and the resin composition. Is excellent, easy to handle, and harmless, but on the other hand, the blackness is still insufficient and the coating film and resin composition obtained using magnetite particle powder The acid resistance and aging resistance of the product were also insufficient.
[0006]
In addition, since magnetite particle powder has magnetism, it tends to cause magnetic agglomeration. From the viewpoint of improving dispersibility in a vehicle or resin composition, it is an iron-based black particle powder having no magnetism. Manganese-containing hematite particle powder and manganese-containing hydrous iron oxide particle powder are known, but these are inferior to magnetite particle powder in terms of blackness.
[0007]
In recent years, improvement in various characteristics of black pigments as colorants has been desired. Advantageous characteristics of carbon black fine particle powder and black iron oxide particle powder such as magnetite particle powder and manganese-containing black hematite particle powder and manganese-containing black goethite particles There is a strong demand for black pigments that combine the advantageous properties of black hydrated iron oxide particles such as powder.
[0008]
That is, it is difficult to disperse in a vehicle or a resin composition, workability such as handleability is poor, and there is a problem in safety and hygiene. There is a strong demand for black pigments that have a blackness that is comparable or inferior to the blackness when only fine particle powders are used, and that have excellent dispersibility in vehicles and resin compositions. . And by including such a black pigment, the coating composition which is excellent in acid resistance, and the resin composition excellent in aging resistance are requested | required strongly.
[0009]
In response to these demands, various attempts have been made to obtain a black pigment having both excellent characteristics by combining carbon black fine particle powder and magnetite particle powder. For example, 1) magnetite precipitated from an aqueous solution A method in which an aqueous dispersion containing carbon black fine particle powder is added to an aqueous suspension containing particles, followed by mixing and stirring to adsorb the carbon black fine particle powder on the particle surface of the magnetite particle powder (Japanese Patent Publication No. 50-13300) 2) Iron-containing waste sludge in which high molecular weight organic substances such as molasses are dissolved and hot gas containing carbon black fine particle powder are introduced into a spray reactor at a temperature of 450 to 850 ° C., and magnetite particle powder is obtained from iron salt. Carbon black fine particle powder using molasses as a binding accelerator on the particle surface of the magnetite particle powder 3) By suspending carbon black in an aqueous iron salt solution and then adding an alkali to coprecipitate the carbon black fine particle powder and iron trioxide. A method for obtaining a coprecipitate whose surface is coated with carbon black fine particle powder (Japanese Patent Publication No. 55-39580), 4) The carbon black fine particle powder or the like is deposited on the surface of the fine plate-like particles, A method of immobilizing the carbon black fine particle powder or the like with an anionic or cationic surfactant, a nonionic surfactant and an organofunctional polysiloxane (JP-A-6-145556, JP-A-7-316458) Etc.) are known.
[0010]
[Problems to be solved by the invention]
Black pigments that combine the advantageous properties of carbon black fine particle powder with the advantageous properties of black iron oxide particle powder and black hydrous iron oxide particle powder are currently the most demanded. However, a black pigment that sufficiently satisfies these characteristics has not been obtained. That is, in the case of the above-mentioned known method 1), the carbon black desorption rate is high as shown in Comparative Example 6 below, and the carbon black fine particle powder is removed during dispersion in the vehicle or the resin composition. Therefore, uniform dispersion in the vehicle or the resin composition is difficult, and the blackness of the obtained paint or resin composition cannot be sufficiently improved.
[0011]
In the case of the above known method 2), in order to obtain the same or inferior blackness as compared with the case where only the carbon black fine particle powder is used, the carbon black fine particle powder is added to 100 parts by weight of the magnetite particle powder. It is necessary to use a large amount of about 280 parts by weight. Also in the case of the above known method 3), in order to obtain the same or inferior blackness as compared with the case where only the carbon black fine particle powder is used, the carbon black fine particle powder is added to 100 parts by weight of the magnetite particle powder. On the other hand, it is necessary to add about 100 to 400 parts by weight, and the carbon black fine particle powder adhering to the surface of the coprecipitate is easily detached. The particle powder obtained by the above-mentioned known method 4) has poor blackness, and the carbon black fine particle powder is easily detached. The particle powder obtained by this method is hardly a black pigment.
[0012]
Therefore, the present invention is excellent in dispersibility in a vehicle or a resin composition because of less carbon black detaching from the particle surface, and uses only carbon black fine particle powder with a small amount of carbon black. In addition to obtaining a black pigment having a blackness equivalent to or comparable to the blackness in the case of the blackness, a paint or aging resistance that forms a coating film excellent in acid resistance by including the black pigment It is a technical problem to obtain a rubber / resin composition having excellent resistance.
[0013]
[Means for Solving the Problems]
The technical problem can be achieved by the present invention as follows.
[0014]
That is, the present invention relates to black iron oxide particle powder or black hydrated iron oxide particle powder, and, if necessary, aluminum hydroxide, aluminum oxide, silicon hydroxide and silicon oxide on the particle surface of the particle powder. The surface of either the black iron oxide particle powder or the black hydrous iron oxide particle powder coated with one or more selected from the above is coated with polysiloxane, and at least a part of the polysiloxane coating An iron-based black composite particle powder having an average particle size of 0.082 to 1.05 μm with carbon black attached to The coating amount of polysiloxane is 0.02 to 5.0% by weight in terms of Si with respect to the polysiloxane-coated black iron oxide particle powder or the polysiloxane-coated black hydrous iron oxide particle powder, The iron-based black composite pigment is characterized in that the carbon black adheres in an amount of 1 to 30 parts by weight with respect to 100 parts by weight of the black iron oxide particle powder or black hydrated iron oxide particle powder.
[0015]
Further, the present invention provides a black iron oxide particle powder or black hydrated iron oxide particle powder having an average particle size of 0.08 to 1.0 μm, and if necessary, an aluminum hydroxide or an aluminum oxide on the particle surface of the particle powder. Mixing and stirring a black iron oxide particle powder or black hydrated iron oxide particle powder and polysiloxane coated with one or more selected from silicon hydroxide and silicon oxide using a kneader Then, after coating the surface of the particle powder with polysiloxane, carbon black fine particles having an average particle diameter of 0.005 to 0.05 μm with respect to 100 parts by weight of the black iron oxide particle powder or black iron oxide hydroxide powder Add 1-30 parts by weight of powder and mix using a kneader And must In short, it is a method for producing the iron-based black composite pigment, characterized in that carbon black is adhered to at least a part of the polysiloxane coating by drying.
[0016]
In addition, the present invention is a paint characterized in that any one of the above iron-based black composite pigments is blended in a paint constituting base material.
[0017]
Further, the present invention is a rubber / resin composition characterized by being colored using any one of the iron-based black composite pigments.
[0018]
The configuration of the present invention will be described in detail as follows.
[0019]
First, the iron-based black composite pigment according to the present invention will be described.
[0020]
In the iron-based black composite pigment according to the present invention, the surface of the black iron oxide particle powder or black hydrated iron oxide particle powder that is the core particle powder is coated with polysiloxane, and at least a part of the polysiloxane coating is carbon. It consists of iron-based black composite particle powder having an average particle size of 0.082 to 1.05 μm to which black is adhered.
[0021]
The core particle powder is a black iron oxide particle powder such as a manganese-containing hematite particle powder containing 5 to 40% by weight of manganese with respect to the magnetite particle powder and the manganese-containing hematite particle powder, or the manganese-containing goethite particle powder. Black hydrated iron oxide particles such as manganese-containing goethite particles containing 5 to 40% by weight of manganese.
[0022]
Considering the dispersibility and blackness of the resulting iron-based black composite pigment in the vehicle or the resin composition, manganese-containing hematite particles are preferred because they are non-magnetic and hardly cause magnetic aggregation.
[0023]
Black iron oxide particles and black hydrated iron oxide particles have various shapes, such as spherical, granular, octahedral, hexahedral, polyhedral, etc., acicular, spindle, rice, etc. And plate-like particles.
[0024]
The particle size of the black iron oxide particle powder and the black hydrated iron oxide particle powder is 0.080 to 1.0 μm, preferably 0.098 to 0.68 μm, more preferably 0 in the case of the granular particle powder. 0.098 to 0.48 μm, and sphericity (ratio of average longest diameter to average shortest diameter) (hereinafter referred to as “sphericity”) is 1.0 or more and less than 2.0, preferably 1.0-1 .8, more preferably 1.0 to 1.5.
[0025]
In the case of the acicular particle powder, the average particle diameter (average major axis diameter) is 0.08 to 1.0 μm, preferably 0.098 to 0.68 μm, more preferably 0.098 to 0.48 μm, The axial ratio (ratio of the average major axis diameter to the average minor axis diameter) (hereinafter referred to as “axis ratio”) is 2 to 20, preferably 3 to 15, and more preferably 3 to 10.
[0026]
In the case of the plate-like particle powder, the average particle diameter (average plate surface diameter) is 0.08 to 1.0 μm, preferably 0.098 to 0.68 μm, more preferably 0.098 to 0.48 μm. The shape ratio (ratio of average plate surface diameter to average thickness) (hereinafter referred to as “plate ratio”) is 2 to 50, preferably 3 to 20, and more preferably 3 to 10.
[0027]
When the average particle diameter exceeds 1.0 μm, the resulting iron-based black composite particles are coarse and the coloring power is reduced. When the average particle size is less than 0.08 μm, aggregation is likely to occur due to an increase in intermolecular force due to the refinement of the particles. Therefore, the surface of the black iron oxide particle powder and the black hydrated iron oxide particle powder is caused by polysiloxane. Uniform coating treatment and uniform adhesion treatment with carbon black become difficult.
[0028]
In the case of acicular particle powder, when the axial ratio exceeds 20, the entanglement of particles increases, and the surface of black iron oxide particle powder and black hydrated iron oxide particle powder is uniformly coated with polysiloxane and uniform with carbon black. Is difficult.
[0029]
In the case of plate-like particle powder, when the plate-like ratio exceeds 50, stacking between particles increases, and the surface of the black iron oxide particle powder and black hydrated iron oxide particle powder is uniformly coated with polysiloxane and carbon black. This makes it difficult to perform uniform adhesion treatment.
[0030]
The BET specific surface area value of the black iron oxide particle powder and the black hydrated iron oxide particle powder is 1.0 to 200 m. ² / G, preferably 2.0 to 150 m ² / G, more preferably 2.5 to 100 m ² / G. BET specific surface area value is 1.0m ² / G, the black iron oxide particle powder and the black hydrated iron oxide particle powder are coarse or sintered between the particles, and the resulting iron-based black composite particles are also Coarse particles are formed and coloring power is reduced. BET specific surface area value is 200m ² / G exceeding, it is easy to cause aggregation due to an increase in intermolecular force due to the refinement of the particles, so that the uniform coating treatment with polysiloxane on the surface of the black iron oxide particle powder and the black hydrous iron oxide particle powder and Uniform adhesion treatment with carbon black becomes difficult.
[0031]
The geometric standard deviation value of the particle diameter of the black iron oxide particle powder and the black hydrated iron oxide particle powder is preferably 1.8 or less, more preferably 1.7 or less. When the geometric standard deviation value exceeds 1.8, uniform dispersion is hindered by the coarse particles present, and therefore, the uniform dispersion of the black iron oxide particle powder and the black hydrated iron oxide particle powder by the polysiloxane on the particle surface is difficult. The coating treatment and the uniform adhesion treatment with carbon black become difficult. The lower limit value of the geometric standard deviation value is 1.01, and those less than 1.01 are difficult to obtain industrially.
[0032]
The blackness of black iron oxide particle powder or black hydrated iron oxide particle powder is usually L in the case of magnetite particle powder. ^* The lower limit of the value exceeds 18.0, and the upper limit is 25.0, preferably 24.0. In the case of manganese-containing hematite particles, usually L ^* The lower limit of the value exceeds 18.0, and the upper limit is 28.0, preferably 26.0. For manganese-containing goethite particles, usually L ^* The lower limit of the value exceeds 18.0, and the upper limit is 30.0, preferably 28.0.
[0033]
L ^* When the value exceeds the above upper limit, it is difficult to say that the blackness is sufficient, and it is difficult to obtain an iron-based black composite pigment excellent in blackness, which is the object of the present invention.
[0034]
The particle shape and particle size of the iron-based black composite pigment according to the present invention largely depend on the particle shape and particle size of the black iron oxide particles and black hydrated iron oxide particles as the core particles, and the particle shape is almost similar to the core particles The particle size is slightly larger than the core particle.
[0035]
That is, the iron-based black composite pigment according to the present invention has a particle size of 0.082 to 1.05 μm, preferably an average particle size of 0.082 to 1.05 μm when granular black iron oxide particles or black hydrated iron oxide particles are used as core particles. The average particle size is 0.1 to 0.7 μm, more preferably the average particle size is 0.1 to 0.5 μm, and the sphericity is 1.0 or more and less than 2.0, preferably 1.0 to 1.8, More preferably, the average particle diameter (average major axis diameter) is 0.082 to 1 when needle-shaped black iron oxide particles or black hydrated iron oxide particles are used as core particles. 0.05 μm, preferably 0.1 to 0.7 μm, more preferably 0.1 to 0.5 μm, and the axial ratio is 2 to 20, preferably 3 to 15, more preferably 3 to 10, When the black iron oxide particles or black hydrated iron oxide particles are used as the core particles, the average particle diameter (average plate Diameter) is 0.082 to 1.05 μm, preferably 0.1 to 0.7 μm, more preferably 0.1 to 0.5 μm, and the plate-like ratio is 2 to 50, preferably 3 to 20, more. Preferably it is 3-10.
[0036]
When the average particle diameter of the iron-based black composite pigment is less than 0.082 μm, aggregation is likely to occur due to an increase in intermolecular force due to the formation of fine particles, and dispersion in the vehicle or the resin composition becomes difficult. When the average particle diameter exceeds 1.05 μm, the coloring power decreases as the particle size increases.
[0037]
When the iron black composite pigment has a needle-like particle shape, if the axial ratio exceeds 20, the particles are entangled, making it difficult to disperse in the vehicle or the resin composition.
[0038]
When the particle shape of the iron-based black composite pigment is plate-like, if the plate-like ratio exceeds 50, stacking between particles increases, and dispersion in the vehicle or the resin composition becomes difficult.
[0039]
The BET specific surface area value of the iron-based black composite pigment is 1.0 to 200 m. ² / G, preferably 2.0 to 150 m ² / G, more preferably 2.5 to 100 m ² / G. BET specific surface area value is 1.0m ² If it is less than / g, the particles are coarse or particles are sintered between particles, which is not preferable because it adversely affects the dispersibility in the vehicle and the resin composition. . BET specific surface area value is 200m ² When the amount exceeds / g, dispersion in the vehicle or the resin composition becomes difficult due to an increase in intermolecular force due to finer particles.
[0040]
The geometric standard deviation value of the particle diameter of the iron-based black composite pigment is preferably 1.8 or less. When the geometric standard deviation value exceeds 1.8, due to the presence of coarse particles, uniform dispersion in the vehicle or resin composition becomes difficult. Considering uniform dispersion in the vehicle or resin composition, it is preferably 1.7 or less. Considering industrial productivity, the lower limit value of the geometric standard deviation value is 1.01, and those less than 1.01 are difficult to obtain industrially.
[0041]
The blackness of the iron-based black composite pigment has an upper limit of L when magnetite particles are used as the core particles. ^* The value is 18.0, preferably 17.5. When manganese-containing hematite particles are used as the core particles, the upper limit is L ^* The value is 18.5, preferably 18.0. When manganese-containing goethite particles are used as the core particles, the upper limit is L ^* The value is 19.0, preferably 18.5. L ^* When the value exceeds the above upper limit, the brightness becomes high and the blackness is not sufficient. The lower limit of blackness is L ^* Is 15.0.
[0042]
The carbon black removal rate of the iron-based black composite pigment is preferably 20% or less, more preferably 10% or less. When the carbon black desorption rate exceeds 20%, the desorbed carbon black may inhibit uniform dispersion in the vehicle or the resin composition during the production of the paint or resin composition. .
[0043]
As the polysiloxane in the iron-based black composite pigment, a polysiloxane represented by Chemical Formula 1, a modified polysiloxane represented by Chemical Formula 2, a terminal modified polysiloxane represented by Chemical Formula 3, or a mixture thereof can be used.
[0044]
[Chemical 1]

[0045]
[Chemical formula 2]

[0046]
[Chemical 3]

[0047]
Considering the adhesion effect and desorption rate of the carbon black fine particle powder, polysiloxane having a methylhydrogensiloxane unit, polyether-modified polysiloxane, and terminal carboxylic acid-modified polysiloxane having a terminal modified with a carboxylic acid are preferable.
[0048]
The coating amount of polysiloxane is preferably 0.02 to 5.0% by weight in terms of Si with respect to the polysiloxane-coated black iron oxide particle powder or the polysiloxane-coated black hydrated iron oxide particle powder. More preferably, it is 0.03-4.0 weight%, More preferably, it is 0.05-3.0 weight%.
[0049]
When it is less than 0.02% by weight, it is difficult to obtain an iron-based black composite pigment having excellent blackness.
[0050]
If it exceeds 5.0% by weight, carbon black should be sufficiently adhered to the particle surface of the black iron oxide particle powder or black hydrated iron oxide particle powder to such an extent that the blackness of the resulting iron-based black composite pigment can be improved. Therefore, there is no point in adding more than necessary.
[0051]
The adhesion amount of carbon black is 1 to 30 parts by weight with respect to 100 parts by weight of black iron oxide particle powder or black hydrated iron oxide particle powder.
[0052]
When the amount is less than 1 part by weight, the amount of carbon black attached is insufficient, and it is difficult to obtain an iron-based black composite pigment having sufficient blackness.
[0053]
When the amount exceeds 30 parts by weight, the resulting iron-based black composite pigment has sufficient blackness, but because of the large amount of carbon black attached, carbon black is easily detached, and as a result, iron-based Dispersibility of the black composite pigment in the vehicle or the resin composition is lowered.
[0054]
The adhesion thickness of carbon black is preferably 0.04 μm or less, more preferably 0.03 μm or less, and still more preferably 0.02 μm or less.
[0055]
In the iron-based black composite pigment according to the present invention, the surface of the black iron oxide particle powder or black hydrated iron oxide particle powder is preliminarily provided with an aluminum hydroxide, an aluminum oxide, a silicon hydroxide and a silicon, if necessary. It may be coated with one or more selected from these oxides (hereinafter referred to as “coating with aluminum hydroxide, etc.”), compared with the case where it is not coated with aluminum hydroxide, etc. Further, the dispersibility of the iron-based black composite pigment in the vehicle or the resin composition is further improved.
[0056]
The coating amount of aluminum hydroxide and the like is Al conversion with respect to black iron oxide particle powder or black hydrated iron oxide particle powder coated with aluminum hydroxide or the like, SiO ₂ Conversion or Al conversion amount and SiO ₂ The total amount with the converted amount is preferably 0.01 to 50% by weight.
[0057]
If it is less than 0.01% by weight, the effect of improving the dispersibility of the iron-based black composite pigment in the vehicle or resin composition cannot be obtained.
[0058]
If it exceeds 50% by weight, the effect of improving the dispersibility of the iron-based black composite pigment in the vehicle or the resin composition can be sufficiently obtained, so there is no meaning of covering more than necessary.
[0059]
The iron-based black composite pigment according to the present invention coated with aluminum hydroxide or the like has almost the same particle size as that of the iron-based black composite pigment according to the present invention not coated with aluminum hydroxide or the like. Size, geometric standard deviation, BET specific surface area, blackness L ^* Value and carbon black desorption rate.
[0060]
Next, a method for producing the iron-based black composite pigment according to the present invention will be described.
[0061]
The granular magnetite particle powder, which is the core particle powder in the present invention, aerated oxygen-containing gas in a suspension containing ferrous hydroxide colloid obtained by reacting a ferrous salt aqueous solution and an alkali hydroxide aqueous solution. It is obtained by a so-called wet method that oxidizes.
[0062]
The granular manganese-containing hematite particle powder is the above-mentioned wet type that generates the granular magnetite particle powder or the granular magnetite particle powder obtained by coating the granular magnetite particle powder generated by the above-described wet method with a manganese compound of 8 to 150 atomic% with respect to the total Fe. The granular manganese-containing magnetite particles obtained by reacting in the presence of manganese in the method to produce granular magnetite particles containing 8 to 150 atomic% manganese based on the total Fe, and then filtering, washing and drying It is obtained by heat-treating any of the powders at 750 to 1000 ° C. in air.
[0063]
Acicular magnetite particle powder and spindle-shaped magnetite particle powder are ferrous hydroxide colloid obtained by reacting ferrous salt aqueous solution with alkali hydroxide aqueous solution, alkali carbonate aqueous solution or alkali hydroxide aqueous solution / alkali carbonate aqueous solution, Oxygen-containing gas is passed through a suspension containing either iron carbonate or iron-containing precipitate and oxidized, so-called wet goethite particle powder or spindle-shaped goethite particle powder is produced by a so-called wet method. It is obtained by filtering the goethite particle powder and washing it with water, followed by heat reduction treatment at 300 to 500 ° C. in a reducing atmosphere.
[0064]
The acicular or spindle-shaped manganese-containing hematite particle powder is obtained by changing the acicular or spindle-shaped goethite particle powder containing 8-150 atomic% manganese to the total Fe obtained by the following method in the air from 400 to 800. It can be obtained by heat dehydration treatment at ° C.
[0065]
The acicular or spindle-shaped manganese-containing goethite particles in the present invention may be reacted in the presence of manganese in the wet method for producing needle-like or spindle-shaped goethite particles in an amount of 8 to 150 atomic% based on the total Fe. It can be obtained by containing manganese.
[0066]
The coating of black iron oxide particle powder or black hydrated iron oxide particle powder with polysiloxane is performed by mechanically mixing and stirring black iron oxide particle powder or black hydrated iron oxide particle powder and polysiloxane, What is necessary is just to mix and stir mechanically, spraying polysiloxane to black hydrous iron oxide particle powder. The added polysiloxane is almost entirely coated on the surface of the black iron oxide particle powder or black hydrated iron oxide particle powder.
[0067]
In order to coat polysiloxane uniformly on the particle surface, it is preferable that the agglomeration of the black iron oxide particle powder or the black hydrous iron oxide particle powder is previously unraveled using a pulverizer.
[0068]
Mixing and stirring black iron oxide particle powder or black hydrated iron oxide particle powder and polysiloxane, mixing carbon black fine particle powder and black iron oxide particle powder or black hydrated iron oxide particle powder whose particle surface is coated with polysiloxane As an apparatus for stirring, an apparatus capable of applying a shearing force to the powder layer is preferable. In particular, an apparatus capable of simultaneously performing shearing, spatula and compression, such as a wheel-type kneader, a ball-type kneader. A blade-type kneader or a roll-type kneader can be used. In carrying out the present invention, a wheel-type kneader can be used more effectively.
[0069]
Specific examples of the wheel type kneader include edge runners (synonymous with “mix muller”, “simpson mill”, “sand mill”), multi-mal, stotz mill, wet pan mill, conner mill, ring muller, and the like. , Preferably an edge runner, multi-mal, Stots mill, wet pan mill, and ring muller, and more preferably an edge runner. Specific examples of the ball kneader include a vibration mill. Specific examples of the blade-type kneader include a Henschel mixer, a planetary mixer, and a nauta mixer. Specific examples of the roll-type kneader include an extruder.
[0070]
The conditions at the time of mixing and stirring are such that the line load is 19.6 to 1960 N / cm (2 to 200 Kg / cm 2) so that the polysiloxane is coated as uniformly as possible on the surface of the black iron oxide particle powder or black hydrated iron oxide particle powder. cm), preferably 98 to 1470 N / cm (10 to 150 Kg / cm), more preferably 147 to 980 N / cm (15 to 100 Kg / cm), and the treatment time is in the range of 5 to 120 minutes, preferably 10 to 90 minutes. The processing conditions may be adjusted as appropriate. In addition, what is necessary is just to adjust process conditions suitably in the range of stirring speed 2-2000rpm, Preferably 5-1000rpm, More preferably, it is 10-800rpm.
[0071]
The amount of polysiloxane added is preferably 0.15 to 45 parts by weight with respect to 100 parts by weight of black iron oxide particle powder or black hydrated iron oxide particle powder. When the amount is less than 0.15 parts by weight, carbon black may be sufficiently adhered to the particle surface of the black iron oxide particle powder or black hydrated iron oxide particle powder to such an extent that the blackness of the obtained iron-based black composite pigment can be improved. Have difficulty. If it exceeds 45 parts by weight, carbon black can be sufficiently adhered to the particle surface of the black iron oxide particle powder or black hydrated iron oxide particle powder to such an extent that the blackness of the obtained iron-based black composite pigment can be improved. There is no point in adding more than necessary.
[0072]
Next, carbon black fine particle powder is added to black iron oxide particle powder or black hydrated iron oxide particle powder coated with polysiloxane, and mixed and stirred to adhere carbon black to the polysiloxane coating. If necessary, drying may be further performed.
[0073]
Commercially available furnace black, channel black or the like can be used as the carbon black fine particle powder used for the adhesion treatment. Specifically, # 3050, # 3150, # 3250, # 3750, # 3950, MA100, MA7, # 1000, # 2400B, # 30, MA77, MA8, # 650, MA11, # 50, # 52, # 45, # 2200B, MA600, etc. (trade name: Mitsubishi Chemical Co., Ltd.) Seast 9H, Seast 7H, Seast 6, Seast 3H, Seast 300, Seast FM, etc. (trade names, Tokai Carbon Co., Ltd.), Raven 1250, Raven 860, Raven 1000, Raven 1190 ULTRA (trade names: Colombian Chemicals Company (made)), Ket Chain Black EC, Ketchembe Rack EC600JD (trade name: Ketchen Black International Co., Ltd.), BLACK PEARLS-L, BLACK PEARLS 1000, BLACK PEARLS 4630, VULCAN XC72, REGAL 660, REGAL 400 (trade name: Cabot Specialty Chemicals, Inc.) (Made)) can be used.
[0074]
Considering the affinity with polysiloxane, MA-100, MA7, # 1000, # 2400B, # 30, BLACK PEARLS-L and BLACK PEARLS 4630 are preferable.
[0075]
The average particle size of the carbon black fine particle powder used for the adhesion treatment is about 0.005 to 0.05 μm, more preferably about 0.010 to 0.035 μm.
[0076]
When it is less than 0.005 μm, the carbon black fine particle powder becomes too fine, and handling becomes difficult.
[0077]
When it exceeds 0.05 μm, the particle size of the carbon black fine particle powder is large, so that a very large mechanical shearing force is required to uniformly adhere to the polysiloxane coating, which is industrially disadvantageous.
[0078]
The carbon black fine particle powder is preferably added over a period of about 5 to 60 minutes while taking a small amount of time.
[0079]
The conditions during mixing and stirring are such that the linear load is 19.6 to 1960 N / cm (2 to 200 Kg / cm), preferably 98 to 1470 N / cm (10 to 150 Kg) so that carbon black adheres uniformly to the polysiloxane coating. / Cm), more preferably 147 to 980 N / cm (15 to 100 Kg / cm), and the treatment time may be suitably adjusted within the range of 5 to 120 minutes, preferably 10 to 90 minutes. In addition, what is necessary is just to adjust process conditions suitably in the range of stirring speed 2-2000rpm, Preferably 5-1000rpm, More preferably, it is 10-800rpm.
[0080]
The addition amount of the carbon black fine particle powder is 1 to 30 parts by weight with respect to 100 parts by weight of the black iron oxide particle powder or the black hydrated iron oxide particle powder. When the amount is less than 1 part by weight, the amount of carbon black attached is insufficient, and an iron-based black composite pigment having sufficient blackness cannot be obtained. When the amount exceeds 30 parts by weight, the resulting iron-based black composite pigment has sufficient blackness, but the amount of carbon black attached increases, so that the carbon black is easily detached from the particle surface, and as a result Further, the dispersibility in the vehicle and the resin composition is lowered.
[0081]
The heating temperature for drying is usually preferably 40 to 200 ° C, more preferably 60 to 150 ° C, and the heating time is preferably 10 minutes to 12 hours, more preferably 30 minutes to 3 hours.
[0082]
If necessary, the black iron oxide particle powder or the black hydrated iron oxide particle powder may have a surface of an aluminum hydroxide, an aluminum oxide, a silicon hydroxide and a silicon prior to mixing and stirring with the polysiloxane. You may coat | cover with 1 type, or 2 or more types chosen from these oxides.
[0083]
Coating with aluminum hydroxide or the like is performed by adding an aluminum compound, a silicon compound, or both of these compounds to an aqueous suspension obtained by dispersing black iron oxide particle powder or black hydrated iron oxide particle powder, and mixing and stirring. Or, if necessary, by adjusting the pH value after mixing and stirring, the surface of the black iron oxide particle powder or black hydrated iron oxide particle powder has aluminum hydroxide, aluminum oxide, silicon One or more selected from hydroxides and silicon oxides are deposited, and then filtered, washed with water, dried and pulverized. If necessary, a deaeration / consolidation process may be further performed.
[0084]
As the aluminum compound, aluminum salts such as aluminum acetate, aluminum sulfate, aluminum chloride, and aluminum nitrate, and alkali aluminates such as sodium aluminate can be used.
[0085]
The addition amount of the aluminum compound is 0.01 to 50% by weight in terms of Al with respect to the black iron oxide particle powder or the black hydrous iron oxide particle powder. When the amount is less than 0.01% by weight, a sufficient amount of aluminum hydroxide or the like sufficient to obtain a dispersibility improving effect in the vehicle or resin composition of the iron-based black composite pigment is applied to the particle surface. It is difficult to coat. If it exceeds 50% by weight, the coating effect is saturated, so there is no point in adding more than necessary.
[0086]
As the silicon compound, No. 3 water glass, sodium orthosilicate, sodium metasilicate, colloidal silica and the like can be used.
[0087]
The addition amount of the silicon compound is SiO to the black iron oxide particle powder or black hydrated iron oxide particle powder. ₂ It is 0.01 to 50% by weight in terms of conversion. When the amount is less than 0.01% by weight, the surface of the particle is coated with a sufficient amount of silicon oxide or the like sufficient to improve the dispersibility of the iron-based black composite pigment in the vehicle or resin composition. Difficult to do. If it exceeds 50% by weight, the coating effect is saturated, so there is no point in adding more than necessary.
[0088]
When an aluminum compound and a silicon compound are used in combination, with respect to black iron oxide particle powder or black hydrated iron oxide particle powder, the amount in terms of Al and SiO ₂ The total amount with the converted amount is preferably 0.01 to 50% by weight.
[0089]
Next, the paint according to the present invention will be described.
[0090]
When the paint according to the present invention is formed using a solvent-based paint, the amount of carbon black present in the paint film is small, even though the amount of carbon black is small. ^* A value of 15.0 to 19.0, preferably 15.0 to 18.5, more preferably 15.0 to 18.0, and a coating film formed using a coating material using only carbon black fine particle powder. Compared to the blackness, the blackness is equal or inferior. Further, the glossiness is 85% or more, preferably 87% or more, more preferably 88% or more, and the acid resistance is ΔG value of 10.0 or less, preferably 9.5 or less, more preferably 9.0 or less. And ΔL ^* The value is 1.0 or less, preferably 0.9 or less, more preferably 0.8 or less.
[0091]
When the paint according to the present invention is formed using a water-based paint, the amount of carbon black present in the paint film is low, even though the amount of carbon black is small. ^* A value of 15.0 to 19.5, preferably 15.0 to 19.0, more preferably 15.0 to 18.5, and a coating film formed using a coating material using only carbon black fine particle powder. Compared to the blackness, the blackness is equal or inferior. Further, the glossiness is 80% or more, preferably 83% or more, more preferably 85% or more, and the acid resistance is ΔG value of 10.0 or less, preferably 9.5 or less, more preferably 9.0. ΔL ^* The value is 1.0 or less, preferably 0.9 or less, more preferably 0.8 or less.
[0092]
The iron-based black composite pigment blended in the paint according to the present invention is 1.0 to 100 parts by weight with respect to 100 parts by weight of the paint-constituting substrate. Considering handling of the paint, it is preferably 2.0 to 100 parts by weight, more preferably 5.0 to 100 parts by weight.
[0093]
Examples of the paint-constituting substrate include an antifoaming agent, an extender pigment, a drying accelerator, a surfactant, a curing accelerator, an auxiliary agent and the like, if necessary, together with a resin and a solvent.
[0094]
Resins in the case of solvent-based paints are commonly used acrylic resins, alkyd resins, polyester resins, polyurethane resins, epoxy resins, phenol resins, melamine resins, amino resins, and the like.
[0095]
Resins in the case of water-based paints are commonly used water-soluble alkyd resins, water-soluble melamine resins, water-soluble acrylic resins, water-soluble urethane emulsion resins, and the like.
[0096]
Solvents for solvent-based paints are commonly used toluene, xylene, butyl acetate, methyl acetate, methyl isobutyl ketone, butyl cellosolve, ethyl cellosolve, butyl alcohol, aliphatic hydrocarbons, and the like.
[0097]
Examples of the solvent for the water-based paint include butyl cellosolve and butyl alcohol which are commonly used in water-based paints in addition to water.
[0098]
Antifoaming agents are Nopco 8034 (product name), SN deformer 477 (product name), SN deformer 5013 (product name), SN deformer 247 (product name), SN deformer 382 (product name) (all of these are San Nopco shares Company-made), anti-home 08 (product name), Emulgen 903 (product name) (all of which are manufactured by Kao Corporation).
[0099]
Next, the rubber / resin composition according to the present invention will be described.
[0100]
Although the rubber / resin composition according to the present invention has a small amount of carbon black present in the rubber / resin composition, L ^* The value is 15.0 to 21.0, preferably 15.0 to 20.5, more preferably 15.0 to 20.0, and the blackness of the rubber / resin composition using only the carbon black fine particle powder. Compared with the same or inferior blackness. The dispersibility in the rubber / resin composition is preferably 4 or 5, more preferably 5, from visual observation. In the aging resistance, the ratio of the discolored portion when heated at 190 ° C. for 90 minutes is 15% or less, preferably 10% or less, more preferably 5% or less.
[0101]
The iron-based black composite pigment blended in the rubber / resin composition according to the present invention is in the range of 0.5 to 200 parts by weight with respect to 100 parts by weight of the constituent base material, and handling of the rubber / resin composition. Is preferably 1.0 to 150 parts by weight, more preferably 2.5 to 100 parts by weight.
[0102]
The base material of the rubber / resin composition is an additive such as a lubricant, a plasticizer, an antioxidant, an ultraviolet absorber, and various stabilizers, if necessary, together with rubber or a known thermoplastic resin.
[0103]
An additive should just be 50 weight% or less with respect to the sum total of an iron-type black composite pigment and rubber | gum or resin. When the content of the additive exceeds 50% by weight, the moldability is lowered.
[0104]
The rubber / resin composition according to the present invention is prepared by thoroughly mixing a rubber or resin raw material and an iron-based black composite pigment in advance, and then applying a strong shearing action under heating using a kneader or an extruder. The aggregate of the black composite pigment is destroyed, and the iron-based black composite particle powder is uniformly dispersed in rubber or resin, and then molded into a shape according to the purpose and used.
[0105]
DETAILED DESCRIPTION OF THE INVENTION
A typical embodiment of the present invention is as follows.
[0106]
The average particle size of each of the black iron oxide particle powder, black hydrated iron oxide particle powder, carbon black fine particle powder, and iron-based black composite pigment is 4 times the electron micrograph (× 20000) in the vertical and horizontal directions, respectively. The fixed direction diameter was measured for each of about 350 particles shown in the enlarged photograph, and the average value was shown.
[0107]
The sphericity is indicated by the ratio of the average longest diameter to the average shortest diameter, the axial ratio is indicated by the ratio of the average long axis diameter to the average short axis diameter, and the plate ratio is the ratio of the average plate surface diameter to the average thickness. It showed in.
[0108]
The geometric standard deviation value of the particle diameter (major axis diameter) was indicated by a value obtained by the following method. That is, the value measured for the particle size shown in the above enlarged photograph is calculated from the measured value, and the particle size is plotted on the horizontal axis on the log-normal probability paper according to a statistical method from the actual particle size and number of particles. The diameter was plotted on the vertical axis in terms of the cumulative number of particles belonging to each of the predetermined particle diameter sections (under the cumulative sieve) as a percentage. Then, from this graph, the particle diameter values corresponding to the cumulative number of particles of 50% and 84.13% are read, and the geometric standard deviation value = (particle diameter at 84.13% under accumulated fluid) / (under accumulated fluid). The value calculated according to the particle diameter (geometric mean diameter) at 50% is shown as the geometric standard deviation value is closer to 1, meaning that the particle diameter (major axis diameter) particle size distribution is excellent.
[0109]
The specific surface area value was indicated by a value measured by the BET method.
[0110]
The amount of Mn, Al, and Si present in the interior and surface of the black iron oxide particle powder, black hydrated iron oxide particle powder, and iron black composite pigment, and the polysiloxane coated with the iron black composite pigment Each amount of Si contained was measured using a “fluorescence X-ray analyzer 3063M type” (manufactured by Rigaku Denki Kogyo Co., Ltd.) according to “General X-ray fluorescence analysis rules” of JIS K0119.
[0111]
The amount of carbon black adhering to the iron-based black composite pigment was determined by measuring the amount of carbon using “Horiba Metal Carbon / Sulfur Analyzer EMIA-2200” (manufactured by Horiba, Ltd.).
[0112]
The thickness of the carbon black adhering to the iron-based black composite pigment was measured using an electron microscope photograph taken using a “transmission electron microscope JEM-2010” (manufactured by JEOL Ltd.) under an acceleration voltage of 200 kV. Was obtained by measuring the average thickness of the carbon black adhering to the surface of the particles shown in the photograph (× 5,000,000) magnified 10 times.
[0113]
The desorption rate (%) of carbon black adhering to the iron-based black composite pigment was indicated by the value obtained by the following method. The closer the desorption rate of carbon black is to 0%, the smaller the desorption amount of carbon black from the particle surface.
[0114]
3 g of iron-based black composite pigment and 40 ml of ethanol were placed in a 50 ml settling tube, subjected to ultrasonic dispersion for 20 minutes, and then allowed to stand for 120 minutes to separate the carbon black released from the iron-based black composite pigment due to the difference in specific gravity. . Next, 40 ml of ethanol was again added to the iron-based black composite pigment, and after further ultrasonic dispersion for 20 minutes, the mixture was allowed to stand for 120 minutes to separate the iron-based black composite pigment from the detached carbon black. This iron-based black composite pigment was dried at 100 ° C. for 1 hour, and the carbon amount was measured using the above-mentioned “Horiba Metal Carbon / Sulfur Analyzer EMIA-2200 Model” (manufactured by Horiba, Ltd.). The value obtained was the carbon black desorption rate.
[0115]
Desorption rate of carbon black (%) = [(Wa-We) / Wa] × 100
Wa: Carbon black adhesion amount of iron-based black composite pigment
We: Carbon black adhesion amount of iron-based black composite pigment after desorption test
[0116]
The blackness of each of the black iron oxide particle powder, the black hydrated iron oxide particle powder and the iron-based black composite pigment was measured by mixing 0.5 g of a sample and 0.7 ml of castor oil into a paste by kneading with a Hoover type Mahler. Add 4.5 g of clear lacquer, knead, paint, and apply the coated piece (coating thickness: about 30 μm) using a 150 μm (6 mil) applicator on cast coated paper. Measurement is performed using a colorimeter MSC-IS-2D (manufactured by Suga Test Instruments Co., Ltd.), and the color index L is determined according to JIS Z 8729. ^* Indicated by value.
[0117]
The blackness of the paint is the blackness of the coating film obtained by applying the paint having the composition described later, and the blackness of the rubber / resin composition is the blackness of the resin plate having the composition described later by multi-light source spectroscopy. Measurement is performed using a color meter MSC-IS-2D (manufactured by Suga Test Instruments Co., Ltd.), and the color index L is determined according to JIS Z 8729. ^* Indicated by value.
[0118]
Where L ^* The value represents lightness and L ^* It shows that blackness is excellent, so that a value is small.
[0119]
The dispersibility in the paint vehicle was evaluated by measuring the glossiness of a coating film produced in the same manner as in the embodiment of the invention.
[0120]
The glossiness was determined by measuring the 20 ° glossiness using “Gloss meter UGV-5D” (manufactured by Suga Test Instruments Co., Ltd.). The higher the glossiness, the better the dispersibility of the particle powder in the paint vehicle.
[0121]
Regarding the viscosity of the paint, the paint viscosity at 25 ° C. of the paint prepared according to the formulation described below was measured using an E-type viscometer (cone plate type viscometer) EMD-R (manufactured by Tokyo Keiki Co., Ltd.) and a shear rate D = 1 .92 sec ^-1 The value at was determined.
[0122]
The dispersibility in the resin composition was evaluated in five stages by visually determining the number of undispersed aggregated particles on the surface of the obtained resin composition. 5 indicates the best dispersion state.
[0123]
1: 1cm ² More than 50 per
2: 1 cm ² 10 or more and less than 50 per
3: 1 cm ² 5 to less than 10 per
4: 1cm ² 1 to less than 5 per
5: Undispersed material not recognized
[0124]
The acid resistance was determined as follows.
[0125]
A sample piece having a coating film produced by coating and drying a paint obtained using a black pigment on a cold-rolled steel sheet (0.8 mm × 70 mm × 150 mm) (JIS G 3141) at a thickness of 150 μm is prepared, Glossiness and blackness were measured.
[0126]
Next, a 5 wt% aqueous sulfuric acid solution was placed in a 1000 ml beaker, the sample piece was hung with a thread, immersed to a depth of about 120 mm, and allowed to stand at 25 ° C. for 24 hours.
[0127]
Next, the sample piece was taken out from the acid solution, gently washed with running water, shaken off the water, and then the gloss and blackness of the central part of the sample piece were measured. And the glossiness change ((DELTA) G) before and behind the immersion to the acid solution of a sample piece, and a blackness change ((DELTA) L). ^* Value) was measured, and the acid resistance was evaluated based on the magnitude. ΔG and ΔL ^* It shows that it is excellent in acid resistance, so that both values are small.
[0128]
Aging resistance is determined by heating the colored resin plate kneaded with a black pigment (length 1.5 cm x width 1.5 cm x thickness 1 mm) at 190 ° C and the area S where the resin deteriorates due to discoloration. Surface area S of the previous colored plate ₀ (1.5 × 1.5 = 2.25cm ² Ratio S / S ₀ Was determined by quantifying in increments of 5%.
[0129]
That is, (S / S ₀ ) × 100 is 0%, indicating no deterioration, (S / S ₀ ) When x100 is 100%, the resin is completely deteriorated.
[0130]
<Manufacture of iron-based black composite pigment>
Manganese-containing black hematite particle powder (particle shape: granular, sphericity 1.3, average particle diameter 0.30 μm, geometric standard deviation value 1.46, BET specific surface area value 3 shown in the electron micrograph (× 20000) of FIG. .6m ² / G, Mn content 13.3% by weight, blackness L ^* Value 22.6) In order to break up the agglomeration, 20 kg was poured into 150 liters of pure water using a stirrer, and “TK Pipeline Homomixer” (product name, manufactured by Tokushu Kika Kogyo Co., Ltd.) was used three times. A slurry containing manganese-containing black hematite particle powder was obtained.
[0131]
Subsequently, the slurry containing this manganese-containing black hematite particle powder was passed five times at a shaft rotational speed of 2000 rpm using a horizontal sand grinder “Mighty Mill MHG-1.5L” (product name, manufactured by Inoue Seisakusho Co., Ltd.). Thus, a dispersion slurry containing manganese-containing black hematite particle powder was obtained.
[0132]
The sieve residue in 325 mesh (aperture 44 μm) of the obtained dispersion slurry containing manganese-containing black hematite particle powder was 0%. The dispersion slurry was filtered and washed with water to obtain a cake of manganese-containing black hematite particles. This manganese-containing black hematite particle powder cake was dried at 120 ° C., and then 11.0 kg of the dried powder was introduced into an edge runner “MPUV-2 type” (product name, manufactured by Matsumoto Foundry Co., Ltd.). The mixture was stirred at 30 cm / cm (30 kg / cm) for 30 minutes to loosen the agglomeration of the particle powder.
[0133]
Next, 110 g of methyl hydrogen polysiloxane (trade name: TSF484: manufactured by Toshiba Silicone Co., Ltd.) is added to the above-mentioned manganese-containing black hematite particle powder that has been released from the aggregation of particles while operating the edge runner, and 588 N / cm. The mixture was stirred for 60 minutes with a linear load of (60 Kg / cm). The stirring speed at this time was 22 rpm.
[0134]
Next, carbon black fine particle powder (particle shape: granular, particle diameter 0.022 μm, geometric standard deviation value 1.68, BET specific surface area value 134 m shown in the electron micrograph (× 20000) in FIG. ² / G, blackness L ^* Value 16.6) 550 g was added over 10 minutes while running the edge runner, and further mixed and stirred at a linear load of 588 N / cm (60 Kg / cm) for 60 minutes to cover the methylhydrogenpolysiloxane coating with carbon black Then, drying was performed at 105 ° C. for 60 minutes using a dryer to obtain an iron-based black composite pigment. The stirring speed at this time was 22 rpm.
[0135]
The obtained iron-based black composite pigment was a granular particle having a particle diameter of 0.31 μm and a sphericity of 1.3 as shown in an electron micrograph (× 20000) in FIG. The geometric standard deviation value is 1.46, and the BET specific surface area value is 8.9 m. ² / G, Mn content is 12.6% by weight, blackness L ^* The value was 18.2, the carbon black desorption rate was 6.4%, and the coating amount of methyl hydrogen polysiloxane was 0.41% by weight in terms of Si. The amount of adhering carbon black is 4.76% by weight in terms of C (corresponding to 5 parts by weight with respect to 100 parts by weight of manganese-containing black hematite particle powder), and the adhesion thickness of carbon black on the particle surface is 0.0023 μm. there were. In the electron micrograph shown in FIG. 3, since almost no carbon black was observed, it was confirmed that almost the entire amount of carbon black was adhered to the methyl hydrogen polysiloxane coating.
[0136]
For comparison, an electron micrograph of a mixed particle powder obtained by mixing and stirring manganese-containing black hematite particle powder and carbon black fine particle powder with an edge runner without coating with methylhydrogenpolysiloxane (× 20000). ) Is shown in FIG. As shown in the electron micrograph of FIG. 4, it was confirmed that carbon black did not adhere to the particle surface of manganese-containing black hematite particles, and both particle powders were mixed separately.
[0137]
<Manufacture of solvent-based paints>
10 g of the iron-based black composite pigment, amino alkyd resin and thinner were blended in the following proportions and added together with 90 g of 3 mmφ glass beads to a 140 ml glass bottle, and then mixed and dispersed for 90 minutes with a paint shaker to prepare a mill base.
[0138]
Iron black complex pigment 12.2 parts by weight
Amino alkyd resin 19.5 parts by weight
(Amirac No. 1026: manufactured by Kansai Paint Co., Ltd.)
Thinner 7.3 parts by weight
[0139]
Using the above mill base, an amino alkyd resin was blended so as to have the following ratio, and further mixed and dispersed in a paint shaker for 15 minutes to obtain a paint containing an iron-based black composite pigment.
[0140]
Mill base 39.0 parts by weight
Aminoalkyd resin 61.0 parts by weight
(Amirac No. 1026: manufactured by Kansai Paint Co., Ltd.)
[0141]
The resulting solvent-based paint had a paint viscosity of 702 cP.
[0142]
The gloss of the coating film produced using this paint is 91%, and the blackness of the coating film is L ^* The value was 18.6. Gloss change ΔG based on the acid resistance test of the film is 6.1%, brightness change ΔL ^* The value was 0.7.
[0143]
<Manufacture of water-based paint>
The above iron-based black composite pigment (7.62 g) and water-soluble alkyd resin and the like were added to a 140 ml glass bottle together with 90 g of 3 mmφ glass beads at the following ratio, and then mixed and dispersed in a paint shaker for 45 minutes or 90 minutes to prepare a mill base.
[0144]
12.4 parts by weight of iron-based black composite pigment
9.0 parts by weight of water-soluble alkyd resin
(Product name: S-118: manufactured by Dainippon Ink & Chemicals, Inc.)
4.8 parts by weight of defoaming agent
(Product name: Nopco 8034: manufactured by San Nopco)
4.8 parts by weight of water
Butyl cellosolve 4.1 parts by weight
[0145]
Using the mill base, the paint composition was blended at the following ratio, and further mixed and dispersed for 15 minutes with a paint shaker to obtain an aqueous paint.
[0146]
Mill base 30.4 parts by weight
Water-soluble alkyd resin 46.2 parts by weight
(Product name: S-118: manufactured by Dainippon Ink & Chemicals, Inc.)
12.6 parts by weight of water-soluble melamine resin
(Product name: S-695: manufactured by Dainippon Ink & Chemicals, Inc.)
Defoamer 0.1 parts by weight
(Product name: Nopco 8034: manufactured by San Nopco)
9.1 parts by weight of water
Butyl cellosolve 1.6 parts by weight
[0147]
The obtained water-based paint had a paint viscosity of 798 cP.
[0148]
The gloss of the coating film produced using this paint is 86%, and the blackness of the coating film is L ^* The value was 18.8. Gloss value change ΔG value based on acid resistance test of coating film is 5.3%, lightness change ΔL ^* The value was 0.7.
[0149]
<Manufacture of resin composition>
2.5 g of the iron-based black composite pigment and 47.5 g of polyvinyl chloride resin powder 103EP8D (manufactured by Nippon Zeon Co., Ltd.) are weighed, put in a 100 ml poly beaker and mixed well with a spatula to obtain a mixed powder. It was.
[0150]
After adding 0.5 g of calcium stearate to the obtained mixed powder and mixing, and setting the clearance of a hot roll heated to 160 ° C. to 0.2 mm, the above mixed powder is kneaded with a roll little by little to obtain a resin composition The kneading was continued until the products were integrated, and then the resin composition was peeled from the roll and used as a colored resin plate raw material.
[0151]
Next, the resin composition is sandwiched between surface-polished stainless steel plates and placed in a hot press heated to 180 ° C., and 98000 kPa (1 ton / cm ² ) To obtain a colored resin plate having a thickness of 1 mm. Blackness L of the obtained colored resin plate ^* The value was 17.9 and the dispersion state was 5.
[0152]
Three test pieces obtained by cutting a colored resin plate into a 1.5 cm square were put in a gear oven heated to 190 ° C., and taken out one by one every 30 minutes to examine the state of resin deterioration. Deterioration degree of resin (S / S ₀ × 100) was 0%, the degree of resin deterioration after 60 minutes was 0%, and the degree of resin deterioration after 90 minutes was 5%.
[0153]
[Action]
In the present invention, the most important point is that the black iron oxide particle powder or the black hydrous iron oxide particle powder, and if necessary, the surface of the black iron oxide particle powder or the black hydrous iron oxide particle powder has aluminum hydroxide, aluminum Polysiloxane is coated on the surface of black iron oxide particle powder or black hydrated iron oxide particle powder coated with one or more compounds selected from oxides, silicon hydroxides and silicon oxides An iron-based black composite particle powder having an average particle diameter of 0.082 to 1.05 μm, in which carbon black is attached to at least a part of the polysiloxane coating, and the amount of carbon black attached is the black The iron-based black composite pigment, which is 1 to 30 parts by weight with respect to 100 parts by weight of the iron oxide particle powder or the black hydrated iron oxide particle powder, is carbon released from the particle surface. Due to the small number of racks, it has excellent dispersibility in vehicles and resin compositions, and is equivalent or inferior to the blackness when only carbon fine particle powder is used with a small amount of carbon black. This is the fact that blackness can be obtained.
[0154]
As for the reason why the amount of carbon black released from the particle surface of the iron-based black composite pigment according to the present invention is small, the present inventor found that the various functional groups possessed by the polysiloxane to which the carbon black is attached are black iron oxide. This is considered to be firmly bonded to the particle surface of the particle powder or black hydrated iron oxide particle powder.
[0155]
As for the reason why the dispersibility of the iron-based black composite pigment according to the present invention in the vehicle or the resin composition is excellent, the present inventor said that the amount of carbon black released from the particle surface of the iron-based black composite pigment is small. As a result, the dispersion in the system is not inhibited by the carbon black, and because the carbon black adheres to the particle surface of the iron-based black composite pigment, unevenness occurs on the particle surface, and the contact between the particles is suppressed. I think because.
[0156]
As for the reason why the blackness of the iron-based black composite pigment according to the present invention is excellent, the present inventor found that the carbon black that normally behaves as an aggregate due to the fine particles is a black iron oxide particle powder or This is due to the fact that the color of the core particles was canceled by the carbon black and the original color of the carbon black was exhibited because the black hydrated iron oxide particles were uniformly and densely attached to the particle surface via the polysiloxane. ing.
[0157]
The coating film formed using the paint containing the iron-based black composite pigment has excellent acid resistance, and the resin composition obtained by blending the iron-based black composite pigment is resistant to aging. Is the fact that is superior.
[0158]
As for the reason why the acid resistance of the coating film formed using the paint according to the present invention and the aging resistance of the resin composition are excellent, the present inventor has carbon black excellent in acid resistance and aging resistance, By attaching to the particle surface of black iron oxide particle powder or black hydrated iron oxide particle powder via polysiloxane, the surface activity is easy to oxidize inherently in black iron oxide particle powder or black hydrated iron oxide particle powder. This is due to the fact that the characteristic of high carbon was canceled and the original characteristics of carbon black were exhibited.
[0159]
【Example】
Next, examples and comparative examples are given.
[0160]
Core particles 1-7
Various black iron oxide particle powders and black hydrated iron oxide particle powders obtained by a known production method were prepared, and the black iron oxide particle powder and the black hydrated water that were deagglomerated in the same manner as in the above embodiment of the invention. An iron oxide particle powder was obtained.
[0161]
Table 1 shows various characteristics of these black iron oxide particle powder and black hydrated iron oxide particle powder.
[0162]
[Table 1]

[0163]
Core particle 8
Using 20 kg of granular manganese-containing black hematite particle powder in which the aggregation of the core particles 1 was unraveled and 150 l of water, a slurry containing granular manganese-containing black hematite particle powder was obtained in the same manner as in the embodiment of the invention. The pH value of the redispersed slurry containing the granular manganese-containing black hematite particles obtained was adjusted to 10.5 using an aqueous sodium hydroxide solution, and then water was added to the slurry to adjust the slurry concentration to 98 g / l. . 150 l of this slurry was heated to 60 ° C., and 2722 ml of a 1.0 mol / l sodium aluminate solution (corresponding to 0.5 wt% in terms of Al with respect to granular manganese-containing black hematite particles) was added to this slurry. In addition, after maintaining for 30 minutes, the pH value was adjusted to 7.5 using acetic acid. After maintaining in this state for 30 minutes, granular manganese-containing black hematite particles having a particle surface coated with aluminum hydroxide were obtained by filtration, washing with water, drying and pulverization.
[0164]
Table 2 shows the main production conditions at this time, and Table 3 shows various characteristics of the granular manganese-containing black hematite particles whose surface is coated with an aluminum hydroxide.
[0165]
In the surface treatment step, the coating type A represents an aluminum hydroxide, and S represents a silicon oxide.
[0166]
Core particles 9-14
A surface-treated core particle powder was obtained in the same manner as the core particle 8 except that the type of the core particle, the type and amount of the additive in the surface treatment step were variously changed.
[0167]
Table 2 shows the main treatment conditions at this time, and Table 3 shows the characteristics of the obtained surface-treated core particle powder.
[0168]
[Table 2]

[0169]
[Table 3]

[0170]
Examples 1-42 and Comparative Examples 1-11
Various types of core particles, presence or absence of polysiloxane in polysiloxane coating process, type and amount added, edge runner treatment conditions, type and amount of carbon black fine particle powder in carbon black adhesion process, and treatment conditions by edge runner Except for the above, an iron-based black composite pigment was obtained in the same manner as in the above embodiment. As for the iron-based black composite pigments obtained in Examples 1 to 42, almost no carbon black was observed as a result of observation with an electron microscope, so that almost all of the carbon black was adhered to the polysiloxane coating. It was recognized that
[0171]
Table 4 shows various properties of the carbon black fine particle powders A to C used.
[0172]
[Table 4]

[0173]
Tables 5 to 10 show main treatment conditions and various characteristics of the obtained iron-based black composite pigment.
[0174]
[Table 5]

[0175]
[Table 6]

[0176]
[Table 7]

[0177]
[Table 8]

[0178]
[Table 9]

[0179]
[Table 10]

[0180]
Comparative Example 12 (Method described in JP-B-50-13300)
A water suspension (1000 ml of a suspension containing 68.3 g of magnetite particle powder) containing magnetite particle powder (black iron oxide) of core particle 3 was prepared and washed 5 times with cold water.
[0181]
Next, an aqueous dispersion of carbon black fine particle powder B (5 g of an aqueous dispersion containing 1.75 g of dry carbon black B) was diluted to 500 ml with cold water.
[0182]
While stirring the suspension of the carbon black fine particle powder, the suspension is added to the aqueous suspension containing the magnetite particle powder for 5 minutes. After the addition is completed, the mixed suspension is stirred for another 10 minutes. Continued and then left.
[0183]
After about 4 hours, the obtained black precipitate was filtered and washed with water five times in the usual manner, and then dried in air at 100 ° C.
[0184]
The resulting black particle powder has a carbon black desorption rate of 50.2% and a blackness of L ^* The value was 20.2, which was almost the same as the blackness of the magnetite particle powder as the core particle powder.
[0185]
<Manufacture of solvent-based paints>
Examples 43 to 84, Comparative Examples 13 to 33
A solvent-based paint was produced in the same manner as in the above-described embodiment except that the type of the black pigment was variously changed.
[0186]
Tables 11 to 13 show the main production conditions at this time and various properties of the obtained coating film.
[0187]
[Table 11]

[0188]
[Table 12]

[0189]
[Table 13]

[0190]
<Manufacture of water-based paint>
Examples 85-126, Comparative Examples 34-54
A water-based paint was produced in the same manner as in the above-described embodiment except that the type of the black pigment was changed.
[0191]
Tables 14 to 16 show the main production conditions and the characteristics of the obtained coating film.
[0192]
[Table 14]

[0193]
[Table 15]

[0194]
[Table 16]

[0195]
<Manufacture of resin composition>
Examples 127-168, Comparative Examples 55-75
A colored resin plate was produced in the same manner as in the embodiment of the present invention except that various kinds of black pigments were changed.
[0196]
Tables 17 to 19 show the main production conditions at this time and various characteristics of the obtained colored resin plate.
[0197]
[Table 17]

[0198]
[Table 18]

[0199]
[Table 19]

[0200]
【Effect of the invention】
The iron-based black composite pigment according to the present invention has excellent dispersibility in a vehicle or a resin composition due to a small amount of carbon black desorbed from the particle surface. Compared to the blackness when using only powder, it has the same or inferior blackness, so it is preferable as a black pigment for paints, printing inks, cosmetics, rubber and resin moldings, etc. is there.
[0201]
The paint according to the present invention obtained using the iron-based black composite pigment, when a coating film is formed using this, is a paint formed using a paint using only carbon black fine particle powder with a small amount of carbon black. Since it has the same or inferior blackness as compared with the blackness of the film, and the acid resistance of the obtained coating film is excellent, it is suitable as a black paint.
[0202]
The rubber / resin composition according to the present invention obtained using the iron-based black composite pigment is equivalent to the blackness of the rubber / resin composition when only carbon fine particle powder is used with a small amount of carbon black. Or it has blackness without inferiority, and since acid resistance is excellent, it is preferable as a black rubber-resin composition.
[0203]
The iron-based black composite pigment according to the present invention is excellent in dispersibility in a vehicle and a resin composition, is easy to handle and has excellent workability, and is industrially and economically advantageous.
[0204]
Further, since the amount of carbon black fine particles used is small, it is preferable from the viewpoint of safety and hygiene.
[Brief description of the drawings]
FIG. 1 is an electron micrograph (× 20000) showing the particle structure of granular manganese-containing black hematite particles used in an embodiment of the invention.
FIG. 2 is an electron micrograph (× 20000) showing the particle structure of the carbon black fine particle powder used in the embodiment of the invention.
FIG. 3 is an electron micrograph (× 20000) showing the particle structure of the iron-based black composite pigment obtained in the embodiment of the invention.
FIG. 4 is an electron micrograph (× 20000) showing the particle structure of a mixed particle powder of manganese-containing black hematite particle powder and carbon black fine particle powder shown for comparison.

Claims (6)

The average particle diameter of 0.082 to 1.05 μm, wherein the surface of the black iron oxide particle powder or black hydrated iron oxide particle powder is coated with polysiloxane, and carbon black is adhered to at least a part of the polysiloxane coating. The amount of the polysiloxane coating is 0.02 to 5.0% by weight in terms of Si with respect to the polysiloxane-coated black iron oxide particle powder or the polysiloxane-coated black hydrated iron oxide particle powder. There, black iron-based composite pigment, wherein the amount of adhesion of the carbon black is the 1-30 parts by weight based on the black iron oxide particles or black iron oxide hydroxide particles 100 parts by weight. One or more selected from the hydroxide of aluminum, the oxide of aluminum, the hydroxide of silicon and the oxide of silicon as a lower layer on the particle surface of black iron oxide particle powder or black hydrated iron oxide particle powder An iron-based black composite particle powder having an average particle size of 0.082 to 1.05 μm, which is coated and coated with polysiloxane as an upper layer, and carbon black is attached to at least a part of the polysiloxane coating , The coating amount of the polysiloxane is 0.02 to 5.0% by weight in terms of Si with respect to the polysiloxane-coated black iron oxide particle powder or the polysiloxane-coated black hydrated iron oxide particle powder. An iron-based black composite pigment characterized by being 1 to 30 parts by weight per 100 parts by weight of iron oxide particle powder or black hydrous iron oxide powder. Black iron oxide particle powder or black hydrous iron oxide particle powder having a mean particle diameter of 0.08 to 1.0 μm and mixed and stirred using a kneader with black iron oxide particle powder or black hydrous iron oxide particle powder and polysiloxane. 1 to 30 carbon black fine particles having an average particle size of 0.005 to 0.05 μm with respect to 100 parts by weight of the black iron oxide particles or black hydrated iron oxide particles. was added at a ratio of parts by weight, were mixed with stirring using a kneader, further by necessary, by drying as claimed in claim 1, wherein the depositing of carbon black in at least a portion of the polysiloxane coating A method for producing iron-based black composite pigments. The particle surface is coated with one or more selected from an aluminum hydroxide, an aluminum oxide, a silicon hydroxide and a silicon oxide. After the black iron oxide particle powder or black hydrous iron oxide particle powder and polysiloxane are mixed and stirred using a kneader to coat the surface of the black iron oxide particle powder or black hydrous iron oxide particle powder with polysiloxane Adding 1 to 30 parts by weight of carbon black fine particle powder having an average particle size of 0.005 to 0.05 μm to 100 parts by weight of the black iron oxide particle powder or black hydrated iron oxide particle powder; were mixed and stirred with further by necessary, iron according to claim 2, wherein the depositing of carbon black in at least a portion of the polysiloxane coating by drying Method for producing a black composite pigment.   3. A paint comprising the iron-based black composite pigment according to claim 1 or 2 blended in a paint constituting base material.   A rubber / resin composition colored using the iron-based black composite pigment according to claim 1.

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