JP2004271791A - Substrate for image receiving sheet for electrophotography, image receiving sheet for electrophotography and image forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image receiving sheet for electrophotography which has excellent silver salt photography like properties (picture quality, color tone, brightness, feeling and the like) and is capable of obtaining high quality picture close to silver salt photographic picture quality, and to provide an image forming method using the image receiving sheet for electrophotography. <P>SOLUTION: In a substrate for the image receiving sheet for electrophotography made by forming polyolefin resin layers on both surfaces of a base paper, the polyolefin resin layer on the side (surface side) on which at least a toner image receiving layer of the substrate is disposed contains a fluorescent bleaching agent of 0.01-0.5 mass% and a bluing agent of 0.01-1.3 mass%. Preferably, the polyolefin resin layer on the side (surface side) on which at least a toner image receiving layer of the substrate is disposed contains a white pigment of 3-30 mass%. In the image receiving sheet for electrophotography, the substrate for the image receiving sheet for electrophotography is used. In the image forming method, the image receiving sheet for electrophotography is used. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０１０９】
本発明のトナー受像層は、前記支持体上に、トナー受像層に用いられるポリマーを含有する塗工液をワイヤーコーター等で塗布し、乾燥することによって設けられる。本発明で使用される前記ポリマーの成膜温度は、プリント前の保存に対しては、室温以上が好ましく、トナー粒子の定着に対しては１００℃以下が好ましい。
【０１１０】
本発明のトナー受像層は、乾燥後の塗布質量は、例えば、１〜２０ｇ／ｍ^２が好ましく、４〜１５ｇ／ｍ^２がより好ましい。
前記トナー受像層の厚みとしては、特に制限はなく、目的に応じて適宜選定することができるが、１〜３０μｍが好ましく、２〜２０μｍがより好ましい。
【０１１１】
〔トナー受像層の諸物性〕
前記トナー受像層は、定着部材との定着温度における１８０度剥離強さは、０．１Ｎ／２５ｍｍ以下が好ましく、０．０４１Ｎ／２５ｍｍ以下がより好ましい。前記１８０度剥離強さは、定着部材の表面素材を用い、ＪＩＳ Ｋ６８８７に記載の方法に準拠して測定することができる。
前記トナー受像層は、白色度が高いのが好ましい。該白色度としては、ＪＩＳＰ ８１２３に規定される方法で測定して、８５％以上が好ましい。また、４４０ｎｍ〜６４０ｎｍの波長域で、分光反射率が８５％以上、かつ同波長域の最大分光反射率と最低分光反射率の差は５％以内が好ましい。更には、４００ｎｍ〜７００ｎｍの波長域で分光反射率は８５％以上が好ましく、かつ同波長域の最大分光反射率と最低分光反射率の差は５％以内がより好ましい。
前記白色度としては、具体的には、ＣＩＥ １９７６（Ｌ^＊ａ^＊ｂ^＊）色空間において、Ｌ^＊値は８０以上が好ましく、８５以上がより好ましく、９０以上が更に好ましい。また、前記白色の色味はできるだけニュートラルであるのが好ましい。白色色味としては、Ｌ^＊ａ^＊ｂ^＊空間において、（ａ^＊）^２＋（ｂ^＊）^２の値は５０以下が好ましく、１８以下がより好ましく、５以下が更に好ましい。
【０１１２】
前記トナー受像層としては、光沢性が高いのが好ましい。光沢度としては、トナーが無い白色から最大濃度の黒色までの全領域において、４５度光沢度は６０以上が好ましく、７５以上がより好ましく、９０以上が更に好ましい。
但し、光沢度は１１０以下が好ましい。１１０を超えると金属光沢のようになり画質として好ましくない。
尚、前記光沢度は、ＪＩＳ Ｚ ８７４１に基づいて測定することができる。
【０１１３】
前記トナー受像層は、平滑性が高いのが好ましい。該平滑度としては、トナーが無い白色から最大濃度の黒色までの全領域において、算術平均粗さ（Ｒａ）は３μｍ以下が好ましく、１μｍ以下がより好ましく、０．５μｍ以下が更に好ましい。
尚、算術平均粗さは、ＪＩＳ Ｂ ０６０１、Ｂ ０６５１、Ｂ ０６５２に基づいて測定することができる。
【０１１４】
前記トナー受像層は、以下の項目における１項目の物性を有することが好ましく、更に好ましくは、複数の項目、最も好ましくは、全ての項目の物性を有することが適当である。
（１）トナー受像層のＴｍ（溶融温度）が３０℃以上、トナーのＴｍ＋２０℃以下である。
（２）トナー受像層の粘度が１×１０^５ＣＰになる温度が、４０℃以上であり、トナーのそれより低い。
（３）トナー受像層の定着温度における貯蔵弾性率（Ｇ’）が、１×１０^２〜１×１０^５Ｐａ、損失弾性率（Ｇ”）が、１×１０^２〜１×１０^５Ｐａである。
（４）トナー受像層の定着温度における損失弾性率（Ｇ”）と、貯蔵弾性率（Ｇ’）との比である損失正接（Ｇ”／Ｇ’）が、０．０１〜１０である。
（５）トナー受像層の定着温度における貯蔵弾性率（Ｇ’）が、トナーの定着温度における貯蔵弾性率（Ｇ”）に対して、−５０〜＋２５００である。
（６）溶融トナーのトナー受像層上の傾斜角が、５０度以下、特に４０度以下である。
また、トナー受像層としては、特許第２７８８３５８号明細書、特開平７−２４８６３７号公報、同８−３０５０６７号公報、同１０−２３９８８９号公報等に開示されている物性等を満足するものが好ましい。
【０１１５】
前記（１）の物性は、示差走査熱量測定装置（ＤＳＣ）により測定することができる。前記（２）〜（３）の物性は、例えば、島津製作所製フローテスターＣＦＴ−５００又は５００Ｄを用いて測定することができる。前記（５）〜（７）の物性は、回転型レオメーター（例えば、レオメトリック社製ダイナミックアナライザーＲＡＤＩＩ）を用いて測定することができる。前記（８）の物性は、協和界面科学（株）製の接触角測定装置を用い、特開平８−３３４９１６号公報に開示した方法で測定することができる。
【０１１６】
前記トナー受像層としては、１×１０^６〜１×１０^１５Ω／ｃｍ^２の範囲（２５℃、６５％ＲＨの条件にて）の表面電気抵抗を有するのが好ましい。
前記表面抵抗が１×１０^６Ω／ｃｍ^２未満であると、トナー受像層にトナーが転写される際のトナー量が充分でなく、得られるトナー画像の濃度が低くなり易いことがある。一方、表面電気抵抗が、１×１０^１５Ω／ｃｍ^２を超えると、転写時に必要以上の電荷が発生し、トナーが充分に転写されず、画像の濃度が低く、電子写真用受像シートの取り扱い中に静電気を帯びて塵埃が付着し易くなる。また、複写時にミスフィード、重送、放電マーク、トナー転写ヌケ等が発生することがある。
ここで、前記表面電気抵抗の測定は、ＪＩＳ Ｋ ６９１１に準拠し、サンプルを温度２０℃、湿度６５％の環境下に８時間以上調湿し、同じ環境下で、アドバンテスト（株）製Ｒ８３４０を使用し、印加電圧１００Ｖの条件で、通電して１分間経過した後に測定することで得られる。
【０１１７】
〔バック層〕
前記バック層は、本発明の電子写真用受像シートにおいて、裏面出力適性付与、裏面出力画質改良、カールバランス改良、機器通過性改良等の目的で、支持体に対して、トナー受像層の反対側に設けられるのが好ましい。
前記バック層の色としては、特に制限はないが、本発明の電子写真用受像シートが、裏面にも画像を形成する両面出力型受像シートの場合、バック層も白色であることが好ましい。白色度及び分光反射率は、表面と同様に８５％以上が好ましい。
また、両面出力適性改良のため、バック層の構成がトナー受像層側と同様であってもよい。バック層には、上記で説明した各種の添加剤を用いることができる。このような添加剤として、特にマット剤や、帯電調整剤等を配合することが適当である。バック層は、単層構成であってもよく、２層以上の積層構成であってもよい。
また、定着時のオフセット防止のため、定着ローラ等に離型性オイルを用いている場合、バック層は、オイル吸収性としてもよい。
前記バック層の厚みは、通常、０．１〜１０μｍが好ましい。
【０１１８】
［その他の層］
前記電子写真用受像シートにおけるその他の層としては、例えば、表面保護層、密着改良層、中間層、下塗り層、クッション層、帯電調節（防止）層、反射層、色味調製層、保存性改良層、接着防止層、アンチカール層、及び、平滑化層等が挙げられる。これらの層は、単層構成であってもよく、２以上の層より構成されていてもよい。
【０１１９】
−表面保護層−
前記表面保護層は、本発明の電子写真用受像シートにおける表面の保護、保存性の改良、取り扱い性の改良、筆記性の付与、機器通過性の改良、アンチオフセット性の付与等の目的で、前記トナー受像層の表面に設けることができる。該表面保護層は、１層であってもよいし、２層以上の層からなっていてもよい。表面保護層には、バインダーとして各種の熱可塑性樹脂、熱硬化性樹脂等を用いることができ、前記トナー受像層と同種の樹脂を用いるのが好ましい。但し、熱力学的特性や、静電特性等は、トナー受像層と同じである必要はなく、各々最適化することができる。
【０１２０】
前記表面保護層には、トナー受像層に使用可能な、前述の各種の添加剤を配合することができる。特に、前記表面保護層には、本発明で使用する離型剤と共に、他の添加剤、例えば、マット剤等を配合することができる。なお、前記マット剤としては、種々の公知のものが挙げられる。
本発明の電子写真用受像シートにおける最表面層（例えば、表面保護層が形成されている場合には、表面保護層等）としては、定着性の点で、トナーとの相溶性が良いのが好ましい。具体的には、溶融したトナーとの接触角が、例えば０〜４０度であることが好ましい。
【０１２１】
−密着改良層等−
前記密着改良層は、本発明の電子写真用受像シートにおいて、支持体及びトナー受像層の密着性を改良する目的で、形成するのが好ましい。密着改良層には、前述の各種の添加剤を配合することができ、特に架橋剤を配合するのが好ましい。また、本発明の電子写真用受像シートには、トナーの受容性を改良するため、該密着改良層及びトナー受像層の間に、更にクッション層等を設けるのが好ましい。
【０１２２】
−中間層−
前記中間層は、例えば、支持体及び密着改良層の間、密着改良層及びクッション層の間、クッション層及びトナー受像層の間、トナー受像層及び保存性改良層との間等に形成することができる。もちろん、支持体、トナー受像層、及び、中間層からなる電子写真用受像シートの場合には、中間層は、例えば、支持体及びトナー受像層の間に存在させることができる。
【０１２３】
なお、本発明の前記電子写真用受像シートの厚みとしては、特に制限はなく、目的に応じて適宜選定することができるが、例えば、５０〜３５０μｍが好ましく、１００〜２８０μｍがより好ましい。
【０１２４】
（トナー）
本発明の電子写真用受像シートは、印刷又は複写の際に、トナー受像層にトナーを受容させて使用される。
前記トナーは、結着樹脂と着色剤とを少なくとも含有し、必要に応じて離型剤、その他の成分を含有する。
【０１２５】
−トナー 結着樹脂−
前記結着樹脂としては、スチレン、パラクロルスチレンなどのスチレン類；ビニルナフタレン、塩化ビニル、臭化ビニル、弗化ビニル、酢酸ビニル、プロピオン酸ビニル、ベンゾエ酸ビニル、酪酸ビニルなどのビニルエステル類；アクリル酸メチル、アクリル酸エチル、アクリル酸ｎ−ブチル、アクリル酸イソブチル、アクリル酸ドデシル、アクリル酸ｎ−オクチル、アクリル酸２−クロルエチル、アクリル酸フェニル、α−クロルアクリル酸メチル、メタクリル酸メチル、メタクリル酸エチル、メタクリル酸ブチルなどのメチレン脂肪族カルボン酸エステル類；アクリロニトリル、メタクリルロニトリル、アクリルアミドなどのビニルニトリル類；ビニルメチルエーテル、ビニルエチルエーテル、ビニルイソブチルエーテルなどのビニルエーテル類；Ｎ−ビニルピロール、Ｎ−ビニルカルバゾール、Ｎ−ビニルインドール、Ｎ−ビニルピロリドンなどのＮ−ビニル化合物類；メタクリル酸、アクリル酸、桂皮酸などのビニルカルボン酸類などビニル系モノマーの単独重合体やその共重合体、更には各種ポリエステル類を使用することができ、各種ワックス類を併用することも可能である。
これらの樹脂の中で、特に本発明のトナー受像層に用いたものと同一系統の樹脂を用いるのが好ましい。
【０１２６】
−トナー 着色剤−
前記着色剤としては、通常トナーに用いられているものを制限なく使用することができ、例えば、カーボンブラック、クロムイエロー、ハンザイエロー、ベンジジンイエロー、スレンイエロー、キノリンイエロー、パーメネントオレンジＧＴＲ、ピラゾロンオレンジ、バルカンオレンジ、ウオッチヤングレッド、パーマネントレッド、ブリリアンカーミン３Ｂ、ブリリアンカーミン６Ｂ、デイポンオイルレッド、ピラゾロンレッド、リソールレッド、ローダミンＢレーキ、レーキレッドＣ、ローズベンガル、アニリンブルー、ウルトラマリンブルー、カルコオイルブルー、メチレンブルークロライド、フタロシアニンブルー、フタロシアニングリーン、マラカイトグリーンオクサレレートなどの種々の顔料が挙げられる。また、アクリジン系、キサンテン系、アゾ系、ベンゾキノン系、アジン系、アントラキノン系、チオインジコ系、ジオキサジン系、チアジン系、アゾメチン系、インジコ系、チオインジコ系、フタロシアニン系、アニリンブラック系、ポリメチン系、トリフェニルメタン系、ジフェニルメタン系、チアジン系、チアゾール系、キサンテン系などの各種染料などが挙げられる。これら着色剤は１種単独で使用してもよいし、複数種類を併せて使用してもよい。
着色剤の含有量は、２〜８質量％の範囲が好ましい。着色剤の含有量が２質量％以上であれば着色力が弱くなることもなく、一方、８質量％以下であれば、透明性が損なわれることもないので好ましい。
【０１２７】
−トナー 離型剤−
前記離型剤としては、原理的には、公知のワックス全てが使用可能であるが、比較的低分子量の高結晶性ポリエチレンワックス、フィッシャートロプシュワックス、アミドワックス、ウレタン化合物など窒素を含有する極性ワックスなどが特に有効である。ポリエチレンワックスの分子量は１０００以下が好ましく、３００〜１０００がより好ましい。
【０１２８】
前記ウレタン結合を有する化合物は、低分子量であっても極性基による凝集力の強さにより、固体状態を保ち、融点も分子量のわりには高く設定できるので好適である。分子量の好ましい範囲は３００〜１０００である。原料は、ジイソシアン酸化合物類とモノアルコール類との組み合わせ、モノイソシアン酸とモノアルコールとの組み合わせ、ジアルコール類とモノイソシアン酸との組み合わせ、トリアルコール類とモノイソシアン酸との組み合わせ、トリイソシアン酸化合物類とモノアルコール類との組み合わせなど、種々の組み合わせを選択することができが、高分子量化させないために、多官能基と単官能基の化合物を組み合わせることが好ましく、また等価の官能基量となるようにすることが重要である。
【０１２９】
具体的な、原料化合物のうちモノイソシアン酸化合物としては、例えば、イソシアン酸ドデシル、イソシアン酸フェニル及びその誘導体、イソシアン酸ナフチル、イソシアン酸ヘキシル、イソシアン酸ベンジル、イソシアン酸ブチル、イソシアン酸アリルなどが挙げられる。
ジイソシアン酸化合物としては、ジイソシアン酸トリレン、ジイソシアン酸４、４’ジフェニルメタン、ジイソシアン酸トルエン、ジイソシアン酸１、３−フェニレン、ジイソシアン酸ヘキサメチレン、ジイソシアン酸４−メチル−ｍ−フェニレン、ジイソシアン酸イソホロンなどが挙げられる。
モノアルコールとしては、メタノール、エタノール、プロパノール、ブタノール、ペンタノール、ヘキサノール、ヘプタノールなど極く一般的なアルコール類を使用することが可能である。
原料化合物のうちジアルコール類としては、エチレングリコール、ジエチレングリコール、トリエチレングリコール、トリメチレングリコールなど多数のグリコール類；トリアルコール類としては、トリメチロールプロパン、トリエチロールプロパン、トリメタノールエタンなどが使用可能であるが、必ずしもこの範囲に限定されない。
【０１３０】
これらのウレタン化合物類は、通常の離型剤のように、混練時に樹脂や着色剤とともに混合して、混練粉砕型トナーとしても使用できる。また、前記の乳化重合凝集溶融法トナーに用いる場合には、水中にイオン性界面活性剤や高分子酸や高分子塩基などの高分子電解質とともに分散し、融点以上に加熱してホモジナイザーや圧力吐出型分散機で強い剪断をかけて微粒子化し、１μｍ以下の離型剤粒子分散液を調製し、樹脂粒子分散液、着色剤分散液などとともに用いることができる。
【０１３１】
−トナー その他の成分−
また、本発明のトナーには、内添剤、帯電制御剤、無機微粒子等のその他の成分を配合することができる。内添剤としては、フェライト、マグネタイト、還元鉄、コバルト、ニッケル、マンガン等の金属、合金、又はこれら金属を含む化合物などの磁性体を使用することができる。
【０１３２】
前記帯電制御剤としては、４級アンモニウム塩化合物、ニグロシン系化合物、アルミや、鉄、クロムなどの錯体からなる染料、トリフェニルメタン系顔料など通常使用される種々の帯電制御剤を使用することができる。なお、凝集、溶融時の安定性に影響するイオン強度の制御や、廃水汚染を減少する観点から水に溶解しにくい材料が好ましい。
【０１３３】
前記無機微粒子としては、シリカ、アルミナ、チタニア、炭酸カルシウム、炭酸マグネシウム、リン酸三カルシウムなど、通常、トナー表面の外添剤を全て使用で、それらをイオン性界面活性剤や高分子酸、高分子塩基で分散して使用することが好ましい。
【０１３４】
更に、乳化重合、シード重合、顔料分散、樹脂粒子分散、離型剤分散、凝集、更には、それらの安定化などに界面活性剤を用いることができる。例えば、硫酸エステル塩系、スルホン酸塩系、リン酸エステル系、せっけん系等のアニオン界面活性剤、アミン塩型、４級アンモニウム塩型等のカチオン系界面活性剤、また、ポリエチレングリコール系、アルキルフェノールエチレンオキサイド付加物系、多価アルコール系等の非イオン性界面活性剤を併用することも効果的である。その際の分散手段としては、回転せん断型ホモジナイザーやメデイアを有するボールミル、サンドミル、ダイノミルなどの一般的なものが使用可能である。
【０１３５】
なお、前記トナーには、必要に応じて更に外添剤を添加してもよい。前記外添剤としては、無機粉末及び有機粒子等が挙げられる。前記無機粒子としては、ＳｉＯ_２、ＴｉＯ_２、Ａｌ_２Ｏ_３、ＣｕＯ、ＺｎＯ、ＳｎＯ_２、Ｆｅ_２Ｏ_３、ＭｇＯ、ＢａＯ、ＣａＯ、Ｋ_２Ｏ、Ｎａ_２Ｏ、ＺｒＯ_２、ＣａＯ・ＳｉＯ_２、Ｋ_２Ｏ・（ＴｉＯ_２）_ｎ、Ａｌ_２Ｏ_３・２ＳｉＯ_２、ＣａＣＯ_３、ＭｇＣＯ_３、ＢａＳＯ_４、ＭｇＳＯ_４等を例示することができる。また、前記有機粒子としては、脂肪酸又はその誘導体や、これ等の金属塩等の粉末、フッ素系樹脂、ポリエチレン樹脂、アクリル樹脂等の樹脂粉末を用いることができる。これらの粉末の平均粒径は、例えば、０．０１〜５μｍが好ましく、０．１〜２μｍがより好ましい。
【０１３６】
前記トナーの製造方法は、特に制限されないが、（ｉ）樹脂粒子を分散させてなる分散液中で凝集粒子を形成し凝集粒子分散液を調製する工程、（ｉｉ）前記凝集粒子分散液中に、微粒子を分散させてなる微粒子分散液を添加混合して前記凝集粒子に前記微粒子を付着させて付着粒子を形成する工程、及び（ｉｉｉ）前記付着粒子を加熱し融合してトナー粒子を形成する工程、とを含むトナーの製造方法により製造することが好ましい。
【０１３７】
−トナー物性等−
本発明のトナーの体積平均粒子径は０．５μｍ以上１０μｍ以下が好ましい。
前記トナーの体積平均粒子径が小さすぎると、トナーのハンドリング（補給性、クリーニング性、流動性等）に悪影響が生じる場合があり、また、粒子生産性が低下する場合がある。一方、トナーの体積平均粒子径が大きすぎると、粒状性、転写性に起因する画質、解像度に悪影響を与える場合がある。
また、本発明のトナーは、前記トナーの体積平均粒子径範囲を満たし、かつ体積平均粒度分布指数（ＧＳＤｖ）は１．３以下が好ましい。
前記体積平均粒度分布指数（ＧＳＤｖ）と数平均粒度分布指数（ＧＳＤｎ）との比（ＧＳＤｖ／ＧＳＤｎ）は０．９５以上が好ましい。
また、本発明のトナーは、前記トナーの体積平均粒子径範囲を満たし、かつ下記式で表される形状係数の平均値は１．００〜１．５０が好ましい。
形状係数＝（π×Ｌ^２）／（４×Ｓ）
（但し、Ｌはトナー粒子の最大長、Ｓはトナー粒子の投影面積を示す。）
トナーが上記条件を満たす場合には、画質、特に、粒状性、解像度に効果があり、また、転写に伴う抜けやブラーが生じにくく、平均粒径が小さくなくてもハンドリング性に悪影響が出にくくなる。
【０１３８】
なお、トナー自体の１５０℃における貯蔵弾性率Ｇ’（角周波数１０ｒａｄ／ｓｅｃで測定）は、１０〜２００Ｐａであることが、定着工程での画質向上とオフセット性の防止の面から適当である。
【０１３９】
（画像形成方法）
本発明の画像形成方法は、加熱加圧処理として、加熱加圧手段と、冷却手段と、冷却剥離部とを有する冷却剥離式のベルト定着型平滑化処理機を用いることが好適である。
前記加熱加圧手段により、前記画像形成層における熱可塑性樹脂の軟化点以上の温度に加熱加圧し、冷却した後、前記加熱加圧手段におけるベルト部材から剥離することが好ましい（冷却剥離処理）。
前記冷却剥離方式のベルト型平滑化処理機の加熱加圧手段としては、特に制限されないが、例えば、加熱ローラと加圧ローラと無端ベルトとの組み合わせなどが挙げられる。前記冷却手段としては、特に制限されないが、例えば、冷気を送風可能であり、冷却温度等を調節可能である冷却装置、ヒートシンク、などが用いられる。
【０１４０】
前記画像形成材料を前記冷却剥離方式のベルト型平滑化処理機の加熱加圧手段に接触させる際には、加圧することが好ましい。この加圧の方法としては、特に制限はないが、ニップ圧を印加するのが好ましい。前記ニップ圧としては、耐水性、表面平滑性に優れ、良好な光沢を有する画像形成を行う観点から、１〜１００ｋｇ／ｃｍ^２が好ましく、５〜３０ｋｇ／ｃｍ^２がより好ましい。また、加熱加圧手段における加熱は、画像形成層における熱可塑性樹脂の軟化点以上の温度であり、用いる熱可塑性樹脂に応じて異なるが、通常、８０℃以上２００℃以下が好ましい。前記冷却手段における冷却温度は、画像形成層における熱可塑性樹脂層が十分に固化する８０℃以下の温度が好ましく、２０〜８０℃がより好ましい。
【０１４１】
前記定着ベルトの表面は、シリコーンゴム、フッ素ゴム、シリコーン樹脂、フッ素樹脂からなる群より選択される少なくとも１種以上からなる薄膜が形成されることが好ましい。中でも、ベルト部材の表面に均一な厚さのフルオロカーボンシロキサンゴム製の層を設ける態様、前記ベルト部材の表面に均一な厚さのシリコーンゴム製の層を有し、かつ該シリコーンゴム層の表面に均一な厚さのフルオロカーボンシロキサンゴム製の層を設ける態様が好ましい。
【０１４２】
前記フルオロカーボンシロキサンゴムとしては、主鎖にパーフルオロアルキルエーテル基及び／又はパーフルオロアルキル基を有するものが好ましい。
このようなフルオロカーボンシロキサンゴムとしては、（Ａ）下記一般式（１）のフルオロカーボンシロキサンを主成分とし、脂肪族不飽和基を有するフルオロカーボンポリマー、（Ｂ）１分子中に２個以上の≡ＳｉＨ基を含有し、上記フルオロカーボンシロキサンゴム組成物中の脂肪族不飽和基量に対して上記≡ＳｉＨ基の含有量が１〜４倍モル量であるオルガノポリシロキサン及び／又はフルオロカーボンシロキサン、（Ｃ）充填剤、（Ｄ）有効量の触媒を含有するフルオロカーボンシロキサンゴム組成物の硬化物が好適に用いられる。
【０１４３】
前記（Ａ）成分のフルオロカーボンポリマーは、下記一般式（１）で示される繰り返し単位を有するフルオロカーボンシロキサンを主成分とし、脂肪族不飽和基を有するものである。
【０１４４】
【化１】

【０１４５】
ここで、上記式（１）において、Ｒ^１０は非置換又は置換の好ましくは炭素数１〜８の一価炭化水素基であり、好ましくは炭素数１〜８のアルキル基又は炭素数２〜３のアルケニル基であり、特にメチル基であることが好ましい。ａ，ｅはそれぞれ０又は１、ｂ，ｄはそれぞれ１〜４の整数、ｃは０〜８の整数である。また、ｘは１以上の整数、好ましくは１０〜３０である。
【０１４６】
このような（Ａ）成分としては、下記式（２）で示すものを挙げることができる。
【０１４７】
【化２】

【０１４８】
前記（Ｂ）成分において、≡ＳｉＨ基を有するオルガノポリシロキサンとしては、ケイ素原子に結合した水素原子を分子中に少なくとも２個有するオルガノハイドロジェンポリシロキサンを挙げることができる。
【０１４９】
また、本発明で用いるフルオロカーボンシロキサンゴム組成物においては、（Ａ）成分のフルオロカーボンポリマーが脂肪族不飽和基を有するものであるときには、硬化剤として上述したオルガノハイドロジェンポリシロキサンを使用することができる。即ち、この場合には、フルオロカーボンシロキサン中の脂肪族不飽和基と、オルガノハイドロジェンポリシロキサン中のケイ素原子に結合した水素原子との間で生ずる付加反応によって硬化物が形成されるものである。
【０１５０】
このようなオルガノハイドロジェンポリシロキサンとしては、付加硬化型のシリコーンゴム組成物に使用される種々のオルガノハイドロジェンポリシロキサンを使用することができる。
【０１５１】
上述したオルガノハイドロジェンポリシロキサンは、一般にその≡ＳｉＨ基の数が、（Ａ）成分のフルオロカーボンシロキサン中の脂肪族不飽和炭化水素基１個に対して、少なくとも１個、特に１〜５個となるような割合で配合することが好適である。
【０１５２】
また、≡ＳｉＨ基を有するフルオロカーボンとしては、上記式（１）の単位又は式（１）においてＲ^１０がジアルキルハイドロジェンシロキシ基であり、かつ末端がジアルキルハイドロジェンシロキシ基又はシリル基等の≡ＳｉＨ基であるものが好ましく、下記式（３）で示すものを挙げることができる。
【０１５３】
【化３】

【０１５４】
前記（Ｃ）成分の充填剤としては、一般的なシリコーンゴム組成物に使用されている種々の充填剤を用いることができる。例えば、煙霧質シリカ、沈降性シリカ、カーボン粉末、二酸化チタン、酸化アルミニウム、石英粉末、タルク、セリサイト及びベントナイト等の補強性充填剤、アスベスト、ガラス繊維、有機繊維等の繊維質充填剤などを例示することができる。
【０１５５】
前記（Ｄ）成分の触媒としては、付加反応用触媒として公知とされている塩化白金酸、アルコール変性塩化白金酸、塩化白金酸とオレフィンとの錯体、白金黒又はパラジウムをアルミナ、シリカ、カーボンなどの担体に担持したもの、ロジウムとオレフィンとの錯体、クロロトリス（トリフェニルフォスフィン）ロジウム（ウィルキンソン触媒）、ロジウム（ＩＩＩ）アセチルアセトネートなどのような周期律表第ＶＩＩＩ族元素又はその化合物が例示されるが、これらの錯体はアルコール系、エーテル系、炭化水素などの溶剤に溶解して用いることが好ましい。
【０１５６】
本発明で用いるフルオロカーボンシロキサンゴム組成物においては、耐薬品性を向上させるという本発明の目的を損なわない範囲において、種々の配合剤を添加することができる。例えば、ジフェニルシランジオール、低重合度の分子鎖末端水酸基封鎖ジメチルポリシロキサン、ヘキサメチルジシラザン等の分散剤、酸化第一鉄、酸化第二鉄、酸化セリウム、オクチル酸鉄等の耐熱性向上剤、顔料等の着色剤等を必要に応じて配合することができる。
【０１５７】
前記本発明のベルト部材は、耐熱性樹脂製又は金属製のベルト本体の表面を上記フルオロカーボンシロキサンゴム組成物で被覆し、加熱硬化することによって得られるが、必要に応じて更に、ｍ−キシレンヘキサフロライド、ベンゾトリフロライド等の溶剤で希釈して塗工液とし、スプレーコート、ディップコート及びナイフコート等の一般的なコーティング法によって塗布することができる。また、加熱硬化の温度、時間は適宜選定することができ、通常温度１００〜５００℃、時間５秒〜５時間の範囲でベルト本体の種類及び製造方法などに応じて選択される。
【０１５８】
前記ベルト部材の表面に形成するフルオロカーボンシロキサンゴム層の厚さは特に限定されるものではないが、通常２０〜５００μｍが好ましく、４０〜２００μｍがより好ましい。
【０１５９】
前記ベルト部材の表面粗さ〔算術平均粗さ（Ｒａ）〕としては、特に、表面平滑性に優れ、良好な光沢を有する画像形成を行える点で、２０μｍ以下が好ましく、５μｍ以下がより好ましく、１μｍ以下が更に好ましい。なお、算術平均粗さは、ＪＩＳ Ｂ ０６０１、Ｂ ０６５１、Ｂ ０６５２に基づいて測定することができる。
る。
【０１６０】
本発明の電子写真用受像シートに画像を形成する方法は、定着ベルトを使用した電子写真方法であれば、特に制限はなく、通常の電子写真法であれば、いずれも適用することができる。
例えば、本発明の電子写真用受像シートには、カラー画像を好ましく形成することができる。カラー画像の形成は、フルカラー画像を形成し得る電子写真装置を用いて行うことができる。通常の電子写真装置は、受像シート搬送部と、潜像形成部と、潜像形成部に近接して配設されている現像部とがあり、機種によっては、装置本体の中央に潜像形成部と受像シート搬送部に近接してトナー像中間転写部を有している。
【０１６１】
更に、画質の向上を図るための方法として、静電転写或いはバイアスローラ転写に代わって、或いは併用して、粘着転写又は熱支援型の転写方式が知られている。例えば、特開昭６３−１１３５７６号公報及び特開平５−３４１６６６号公報にはその具体的な構造が記載されている。特に熱支援型転写方式の中間転写ベルトを用いた方法は、小粒径のトナーを使用する場合には好ましい。
【０１６２】
本発明の画像形成方法によれば、定着オイルのないオイルレス機を使用しても、電子写真用受像シート及びトナーの剥離性、或いは電子写真用受像シート及びトナー成分のオフセットを防止でき、安定した給紙を実現できると共に、これまでにない良好な光沢性を有し、写真感覚に富む、良好な画像を実現できる。
【０１６３】
図１は、本発明の電子写真装置（例えば、富士ゼロックス製フルカラーレーザープリンター（ＤＣＣ−５００））を示し、該電子写真装置のベルト状定着部が図２のベルト定着型平滑化処理機に改造して用いられている。図１中、１００は画像形成装置、３７は感光体ドラム、９は現像装置、３１は中間転写ベルト、１６は記録シート、２５はベルト状定着部、をそれぞれ示す。
図２は、上記図１の電子写真装置（画像形成装置）１００の内部に配設されるベルト式定着部２５を示す。
このベルト式定着装置２５は、図２に示すように、加熱ロール７１と、該加熱ロール７１を含む剥離ロール７４、テンションロール７５により回動可能に支持された無端ベルト７３と、前記加熱ロール７１に無端ベルト７３を介して圧接する加圧ロール７２とを備えている。
また、前記無端ベルト７３の内面側には、加熱ロール７１と剥離ロール７４との間に、該無端ベルト７３を強制的に冷却する冷却用のヒートシンク７７が配設されており、この冷却用ヒートシンク７７によって電子写真用受像シートの冷却及びシートの搬送を行う冷却・シート搬送部が構成されている。
【０１６４】
そして、前記ベルト式定着装置２５では、図２に示すように、表面にカラートナー画像が転写・定着された電子写真用転写シートが、加熱ロール７１と当該加熱ロール７１に無端ベルト７３を介して圧接する加圧ロール７２との圧接部（ニップ部）に、カラートナー画像が加熱ロール７１側に位置するようにして導入され、上記加熱ロール７１と加圧ロール７２との圧接部を通過する間に、カラートナー画像Ｔが電子写真用転写シート上に加熱溶融されて定着される。
【０１６５】
その後、前記加熱ロール７１と加圧ロール７２との圧接部において、例えば、トナーが実質的に１２０〜１３０℃程度の温度に加熱され、溶融されて、カラートナー画像が受像層に定着された電子写真用受像シートは、その表面の受像層が無端ベルト７３の表面に密着したまま状態で、当該無端ベルト７３と共に搬送される。その間、上記無端ベルト７３は、冷却用のヒートシンク７７によって強制的に冷却され、カラートナー画像及び受像層が冷却して固化した後、剥離ロール７４によって電子写真用受像シート自身の腰（剛性）によって剥離される。
【０１６６】
なお、剥離工程が終了した後の無端ベルト７３の表面は、クリーナ（図示せず）によって残留トナー等が除去され、次の定着工程に備えるようになっている。
【０１６７】
本発明の電子写真用受像シートに画像を形成する方法は、定着ベルトを使用した電子写真方法であれば、上記方法に制限されるものではない。通常の電子写真法であれば、いずれも適用することができる。
例えば、本発明の電子写真用受像シートには、カラー画像を好ましく形成することができる。カラー画像の形成は、フルカラー画像を形成し得る電子写真装置を用いて行うことができる。通常の電子写真装置は、受像シート搬送部と、潜像形成部と、潜像形成部に近接して配設されている現像部とがあり、機種によっては、装置本体の中央に潜像形成部と受像シート搬送部に近接してトナー像中間転写部を有している。
【０１６８】
更に、画質の向上を図るための方法として、静電転写或いはバイアスローラ転写に代わって、或いは併用して、粘着転写又は熱支援型の転写方式が知られている。例えば、特開昭６３−１１３５７６号公報及び特開平５−３４１６６６号公報にはその具体的な構造が記載されている。特に熱支援型転写方式の中間転写ベルトを用いた方法は、小粒径のトナーを使用する場合には好ましい。
【０１６９】
本発明の画像形成方法によれば、定着オイルのないオイルレス機を使用しても、電子写真用受像シート及びトナーの剥離性、或いは電子写真用受像シート及びトナー成分のオフセットを防止でき、安定した給紙を実現できると共に、これまでにない良好な光沢性を有し、写真感覚に富む、良好な画像を実現できる。
【０１７０】
【実施例】
以下、本発明の実施例について説明するが、本発明はこれらの実施例に何ら限定されるものではない。
なお、以下の実施例及び比較例において、「％」及び「部」は、質量基準である。
【０１７１】
（実施例１〜６及び比較例１〜４）
−支持体の作製−
広葉樹晒クラフトパルプ（ＬＢＫＰ；白色度９０％）をディスクリファイナーで３００ｍｌ（カナダ標準ろ水度、Ｃ．Ｆ．Ｓ．）まで叩解し、繊維長０．６０ｍｍに調整した。このパルプ紙料に対して、パルプの質量に基づいて、以下の割合で添加剤を添加した。

注）前記ＡＫＤは、アルキルケテンダイマー（アルキル部分は、ベヘン酸を主体とする脂肪酸由来のものである）を意味する。前記ＥＦＡは、エポキシ化脂肪酸アミド（脂肪酸部分は、ベヘン酸を主体とする脂肪酸由来のものである）を意味する。
【０１７２】
得られたパルプ紙料を、長網抄紙機により絶乾燥坪量１６０ｇ／ｍ^２の原紙を作製した。なお、なお、長網抄紙機の乾燥ゾーンの中間でサイズプレス装置により、固形分でＰＶＡ １．２ｇ／ｍ^２、ＣａＣＯ_３ ０．９ｇ／ｍ^２を付着した。
その後、マシンカレンダーを用いて、原紙のトナー受像層を設ける側の面（表面）に表面温度が１１０℃の金属ロールが接するように通紙し、カレンダー処理を行った。なお、原紙の反対側の面（裏面）は表面温度４０℃の金属ロールが接するようにした。
更に、ソフトカレンダーを用いて、原紙の表面に表面温度２１０℃の金属ロール、裏面には表面温度４０℃の樹脂ロールが接するように通紙し、カレンダー処理を行い、密度１．０３ｇ／ｃｍ^３の原紙を作製した。
【０１７３】
下記（１）〜（４）の４種類のペレットを混合して、表１に示す蛍光増白剤、群青、ＴｉＯ_２の含有量を有する樹脂組成物を調製した。
（１）ＰＥ：１００質量％
（２）ベンゾオキゾリルスチルベン系化合物：２質量％＋ＰＥ：９８質量％
（３）群青（青群青／紫群青＝１／２（質量比））：６質量％＋ＰＥ：９４質量％
（４）ＴｉＯ_２：５０質量％＋ＰＥ：５０質量％
なお、前記（１）〜（４）におけるＰＥは、いずれもＨＤＰＥ／ＬＤＰＥ＝１／１（質量比）である。
【０１７４】
得られた各樹脂組成物を、トナー受像層を設ける側の面（表面）に塗布し、乾燥膜厚が２５μｍのポリエチレン樹脂層を形成した。
一方、ＨＤＰＥ／ＬＤＰＥ＝１／１（質量比）からなる樹脂組成物をトナー受像層を設けない側の面（裏面）に塗布し、乾燥膜厚が２０μｍのポリエチレン樹脂層を形成した。
続いて、表面側にコロナ放電処理を行い、ゼラチンを０．１ｇ／ｍ^２塗布した。また、裏面にコロナ放電処理を行い、ゼラチンを０．０６ｇ／ｍ^２、コロイダルシリカを０．０２ｇ／ｍ^２塗布し、実施例１〜６及び比較例１〜４の支持体を作製した。
【０１７５】
【表１】

＊１：スチルベン系蛍光増白剤
＊２：群青（青群青／紫群青＝１／２（質量比））
＊３：ベンゾオキゾリルスチルベン系蛍光増白剤
【０１７６】
−電子写真用受像シートの作製−
得られた実施例１〜６及び比較例１〜４の各支持体を用いて、下記のようにして電子写真用受像シートを作製した。
【０１７７】
＜トナー受像層用塗布液の調製＞
（二酸化チタン分散液）
下記の成分を混合し、日本精機製作所製ＮＢＫ−２を用いて分散させ、二酸化チタン分散液（二酸化チタン顔料４０質量％）を作製した。
二酸化チタン
（タイペーク（登録商標）Ａ−２２０、石原産業製） ４０．０ｇ
ＰＶＡ１０２ ２．０ｇ
イオン交換水 ５８．０ｇ
【０１７８】
（トナー受像層用塗布液）
下記成分を混合し、攪拌して、トナー受像層用塗布液を調製した。
上記二酸化チタン分散液 １５．５ｇ
カルナバワックス分散液
（セロゾール５２４、中京油脂（株）製） １５．０ｇ
ポリエステル樹脂水分散物
（固形分３０％、ＫＺＡ−７０４９、ユニチカ製） １００．０ｇ
増粘剤（アルコックスＥ３０、明成化学製） ２．０ｇ
アニオン界面活性剤（ＡＯＴ） ０．５ｇ
イオン交換水 ８０ｍｌ
得られたトナー受像層用塗布液の粘度は、４０ｍＰａ・ｓであり、表面張力は３４ｍＮ／ｍ、ポリエステル樹脂のＴｇは６１℃であった。
【０１７９】
＜バック層用塗布液の調製＞
下記の成分を混合し、攪拌して、バック層用塗布液を調製した。
アクリル樹脂水分散物
（固形分３０％、ハイロスＸＢＨ−９９７Ｌ、星光化学製） １００．０ｇ
マット剤
（テクポマーＭＢＸ−１２、積水化成品工業（株）製） ５．０ｇ
離型剤（ハイドリンＤ３３７、中京油脂（株）製） １０．０ｇ
増粘剤（ＣＭＣ） ２．０ｇ
アニオン界面活性剤（ＡＯＴ） ０．５ｇ
イオン交換水 ８０ｍｌ
バック層用塗布液の粘度は、３５ｍＰａ・ｓであり、表面張力は、３３ｍＮ
／ｍであった。
【０１８０】
＜バック層及びトナー受像層の塗工＞
得られた実施例１〜６及び比較例１〜４の各支持体の裏面に、上記バック層用塗布液をバーコーターで塗布した。次いで、支持体の表面に、上記トナー受像層用塗布液を、バック層の場合と同様に、バーコーターで塗布した。
塗布量は、バック層については、乾燥質量で９ｇ／ｍ^２であり、トナー受像層については、乾燥質量１２ｇになるように、トナー受像層用塗布液及びバック層用塗布液を塗布した。なお、トナー受像層中の熱可塑性樹脂の含有量は、トナー受像層の全質量の６４質量％であった。
バック層及びトナー受像層は、塗布後、オンラインで熱風により乾燥した。乾燥は、バック面及びトナー受像面ともに塗布後２分以内に乾燥するように、乾燥風量及び温度を調整した。乾燥点は、塗布表面温度が乾燥風の湿球温度と同じ温度となる点とした。
乾燥後、ソフトカレンダー処理を行った。ソフトカレンダー処理は、ソフトカレンダーを用い、トナー受像層面に表面温度５５℃の金属ローラが接するように通紙して行い、ニップ圧２３５ｋＮ／ｍにて行った。
【０１８１】
＜評価＞
得られた電子写真用受像シートを、Ａ４に裁断し、女の人のポートレイト画像をプリント用画像とした。使用したプリンターは、図１に示した富士ゼロックス製フルカラーレーザープリンター（ＤＣＣ−５００）の定着部を、図２に示したベルト状定着部に改造した画像形成装置（ベルト及び冷却条件は下記のとおりである）を用いた。
−ベルト−
ベルトの支持体：ポリイミド（ＰＩ）フイルム、幅＝５０ｃｍ、
厚み＝８０μｍ
ベルトの離型層素材：フルオロカーボンシロキサンゴム前駆体であるＳＩＦＥＬ６１０を加硫硬化してフルオロカーボンシロキサンゴム５０μｍの膜厚に形成した。
−冷却条件−
冷却器：ヒートシンク長＝８０ｍｍ
速度：５３ｍｍ／ｓｅｃ
【０１８２】
＜官能画質評価＞
得られた実写画像サンプルについて、比較的写真の画質の評価に長けている者により銀塩写真ライク適性としての画質、色調、及び輝度を下記基準で評価した。結果を表２に示す。
［評価基準］
Ａ：銀塩写真同等の画質である。
Ｂ：銀塩写真に近い画質であり、写真として許容できる。
Ｃ：銀塩写真とは異なる画質であるが、写真としてある程度許容できる。
Ｄ：銀塩写真から明らかに画質が劣り、写真として許容できない。
Ｅ：全く画質が許容できない。
【０１８３】
【表２】

【０１８４】
【発明の効果】
本発明によると、原紙の両面にポリオレフィン樹脂層を設けてなり、該ポリオレフィン樹脂層中における蛍光増白剤とブルーイング剤との含有量を適正化した電子写真用受像シート用支持体が得られる。
また、本発明によると、該電子写真用受像シート用支持体を用いた良好な銀塩写真ライク適性（画質、色調、輝度、風合など）を備え、銀塩写真画質に近い高画質な電子写真プリントが得られる電子写真用受像シートを提供できる。
【図面の簡単な説明】
【図１】図１は、本発明の電子写真装置の一例を示す概略図である。
【図２】図２は、図１の定着部で用いられる冷却剥離式のベルト定着型平滑化処理機の一例を示す概略図である。
【符号の説明】
２５ ベルト式定着装置
７１ 加熱ロール
７２ 加圧ロール
７４ 剥離ロール
７５ テンションロール
７３ 無端ベルト
７７ 冷却ヒートシンク
１００ 画像形成装置[0001]
BACKGROUND OF THE INVENTION
The present invention provides a support for an electrophotographic image-receiving sheet, comprising a polyolefin resin layer on both sides of a base paper, wherein the contents of the fluorescent whitening agent and the bluing agent in the polyolefin resin layer are optimized. The present invention relates to an electrophotographic image-receiving sheet having good silver salt photographic-like suitability (image quality, color tone, luminance, texture, etc.) using a support for an image-receiving sheet, and an image forming method using the electrophotographic image-receiving sheet.
[0002]
[Prior art]
Conventionally, a resin-coated support (double-sided polyolefin resin-coated paper) used for silver-salt photographic prints has been used as a support for electrophotographic image-receiving sheets in order to achieve high-quality images of silver-salt photographic-like in electrophotography It is used. As a result, an electrophotographic image-receiving sheet having high smoothness, gloss and flatness and excellent in image quality and handling is obtained (see, for example, Patent Documents 1 to 3).
[0003]
However, the conventional electrophotographic image-receiving sheets are inferior to silver-salt photographic prints in terms of image quality, color tone, brightness, texture, and the like of recorded images. In order to obtain a high-quality print, the present situation is that further improvement and development is desired.
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 8-21645
[Patent Document 2]
JP 2000-10327 A
[Patent Document 3]
JP 2001-56585 A
[0005]
[Problems to be solved by the invention]
An object of the present invention is to solve the conventional problems and achieve the following objects. That is, the present invention provides a support for an electrophotographic image-receiving sheet, comprising a polyolefin resin layer on both sides of a base paper, wherein the content of the fluorescent brightening agent and the bluing agent in the polyolefin resin layer is optimized. For electrophotography that has good silver salt photographic-like suitability (image quality, color tone, brightness, texture, etc.) using a support for an electrophotographic image-receiving sheet, and provides high-quality electrophotographic prints close to silver salt photographic image quality An object of the present invention is to provide an image receiving sheet and an image forming method using the electrophotographic image receiving sheet.
[0006]
[Means for Solving the Problems]
Means for solving the problems are as follows. That is,
<1> In a support for an electrophotographic image-receiving sheet provided with a polyolefin resin layer on both sides of a base paper, the polyolefin resin layer on the side (surface side) on which at least the toner image-receiving layer is provided is a fluorescent brightening agent 0 An electrophotographic image-receiving sheet support comprising 0.01 to 0.5% by mass and a bluing agent of 0.01 to 1.3% by mass.
<2> The electrophotographic photo described in <1>, wherein the optical brightener is at least one selected from a stilbene compound, a benzoxazolyl stilbene compound, a coumarin compound, a pyrazole compound, and an oxazole compound. Image receiving sheet support.
<3> The support for an electrophotographic image-receiving sheet according to any one of <1> to <2>, wherein the bluing agent is at least one selected from ultramarine, cobalt blue, cobalt oxide phosphate and quinacdrine pigments. Is the body.
<4> The support for an electrophotographic image-receiving sheet according to <3>, wherein the bluing agent is ultramarine, and the ultramarine is a mixture of blue and blue.
<5> For electrophotography according to any one of <1> to <4>, wherein the polyolefin resin layer on the side (surface side) on which at least the toner image-receiving layer is provided contains 3 to 30% by mass of a white pigment. It is a support for an image receiving sheet.
<6> The white pigment is at least one selected from titanium dioxide, calcium carbonate, barium sulfate, zinc white, kaolin, calcined kaolin, magnesium carbonate, aluminum silicate, calcium silicate, magnesium silicate, and synthetic amorphous silica. The support for an electrophotographic image-receiving sheet according to <5>, which is a seed.
<7> The support for an electrophotographic image-receiving sheet according to any one of <1> to <6>, wherein the base paper contains a pulp stock whose pulp whiteness specified by JIS P8123 is 88% or more. is there.
<8> The support for an electrophotographic image-receiving sheet according to any one of <1> to <7>, wherein the base paper contains a pulp paper stock having a mass average fiber length of 0.45 to 0.70 mm.
<9> The support for an electrophotographic image-receiving sheet according to any one of <1> to <8>, wherein the base paper contains at least one of an alkyl ketene dimer and an epoxidized fatty acid amide as a sizing agent.
<10> The support for an electrophotographic image-receiving sheet according to any one of <1> to <9>, wherein the base paper contains 0.01 to 0.5% by mass of a fluorescent brightening agent.
<11> A support, and at least one toner image-receiving layer is provided on one surface of the support, and at least one back layer is provided on the other surface of the support. An electrophotographic image-receiving sheet using the electrophotographic image-receiving sheet support according to any one of <1> to <10>.
<12> For electrophotography according to <11>, using a cooling and peeling type belt-fixing type smoothing processing machine having a heating and pressing unit, a cooling unit, and a cooling and peeling unit. An image forming method comprising heating and pressurizing to a temperature equal to or higher than a softening point of a thermoplastic resin in a toner image receiving layer of an image receiving sheet, cooling, and then peeling from a belt member in the heating and pressurizing unit.
<13> The image forming method according to <12>, wherein a fluorocarbonsiloxane rubber layer having a uniform thickness is provided on a surface of the fixing belt.
<14> The <12>, wherein the surface of the fixing belt has a layer made of silicone rubber having a uniform thickness, and the surface of the silicone rubber layer is provided with a layer made of fluorocarbon siloxane rubber having a uniform thickness. The image forming method described in 1.
<15> The image forming method according to any one of <13> to <14>, wherein the fluorocarbon siloxane rubber has a perfluoroalkyl ether group and / or a perfluoroalkyl group in a main chain.
[0007]
The support for an electrophotographic image-receiving sheet of the present invention comprises a polyolefin resin layer provided on both sides of a base paper, and the polyolefin resin layer on the side (surface side) on which at least the toner image-receiving layer is provided is a fluorescent whitening agent. It contains 0.01 to 0.5% by mass and 0.01 to 1.3% by mass of a bluing agent. As a result, the contents of the fluorescent brightening agent and the bluing agent in the polyolefin resin layer of the support are optimized, and a high-quality electrophotographic print close to the silver salt photographic image quality is obtained.
[0008]
The electrophotographic image-receiving sheet of the present invention comprises a support, at least one toner image-receiving layer on one side of the support, and at least one back layer on the other side of the support. The support for an electrophotographic image-receiving sheet of the present invention is used as the support. As a result, a high-quality electrophotographic print having good silver salt photographic-like suitability such as image quality, color tone, brightness, and texture can be obtained.
[0009]
The image forming method of the present invention uses a cooling / peeling type belt fixing type smoothing processor having a heating / pressurizing unit, a cooling unit, and a cooling / peeling unit, and cools and peels the electrophotographic image-receiving sheet of the present invention. To process. As a result, even if an oil-less machine without fixing oil is used, stable paper feeding without offset to the fixing roller and fixing belt can be realized, and the glossiness is unprecedented. A high-quality image close to the quality of a silver salt photograph can be obtained.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
(Support for electrophotographic image-receiving sheet)
The support for an electrophotographic image-receiving sheet of the present invention comprises a polyolefin resin layer on both sides of a base paper, and further has other layers as necessary.
[0011]
-Base paper-
The base paper is not particularly limited and may be appropriately selected depending on the intended purpose. For example, high-quality paper, edited by the Japan Photography Society, “Basics of Photographic Engineering—Silver Salt Photography”, published by Corona Co., Ltd. ( (Showa 54) Papers described on pages (223) to (240) are preferable.
[0012]
The raw material of the base paper (including synthetic paper) is not particularly limited and can be appropriately selected from various materials. For example, natural pulp selected from softwood and hardwood, synthetic pulp made of plastic materials such as polyethylene and polypropylene Or a mixture of natural pulp and synthetic pulp.
[0013]
The pulp that can be used as the raw material of the base paper is hardwood bleached kraft pulp (LBKP) from the viewpoint of improving the surface smoothness, rigidity and dimensional stability (curlability) of the base paper at the same time in a well-balanced and sufficient level. Preferably, softwood bleached kraft pulp (NBKP), hardwood sulfite pulp (LBSP) and the like can also be used.
The pulp fiber preferably has a mass average fiber length of 0.45 to 0.70 mm.
A beater or refiner can be used for beating the pulp. In the pulp slurry obtained after beating the pulp (hereinafter sometimes referred to as “pulp paper material”), various additives such as a filler, a dry paper strength enhancer, a sizing agent, and wet paper are used as necessary. A force enhancer, a fixing agent, a pH adjuster, other agents, and the like can be added.
The pulp whiteness specified in JIS P8123 in the pulp stock is preferably 88% or more, more preferably 90% or more.
When the pulp whiteness is less than 88%, yellowishness tends to be conspicuous, and adjustment with a fluorescent whitening agent or a bluing agent may be difficult.
[0014]
Examples of the filler include calcium carbonate, clay, kaolin, white clay, talc, titanium oxide, diatomaceous earth, barium sulfate, aluminum hydroxide, and magnesium hydroxide.
Examples of the dry paper strength enhancer include cationized starch, cationized polyacrylamide, anionized polyacrylamide, amphoteric polyacrylamide, and carboxy-modified polyvinyl alcohol.
Examples of the sizing agent include fatty acid salts, rosin derivatives such as rosin and maleated rosin, paraffin wax, alkyl ketene dimer, alkenyl succinic anhydride (ASA), compounds containing higher fatty acids such as epoxidized fatty acid amide, etc. Among these, alkyl ketene dimers and epoxidized fatty acid amides are preferable.
Examples of the wet paper strength enhancer include polyamine polyamide epichlorohydrin, melamine resin, urea resin, and epoxidized polyamide resin.
Examples of the fixing agent include polyvalent metal salts such as aluminum sulfate and aluminum chloride, and cationic polymers such as cationized starch.
Examples of the pH adjuster include caustic soda and sodium carbonate.
As said other chemical | medical agent, an antifoamer, dye, a slime control agent etc. are mentioned, for example.
Furthermore, a softening agent etc. can also be added as needed. Examples of the softening agent are described in New Handbook for Paper Processing (Edited by Paper Medicine Time), pages 554 to 555 (issued in 1980).
[0015]
The treatment liquid used for the surface sizing treatment may contain, for example, a fluorescent brightener, a water-soluble polymer, a water-resistant substance, a pigment, a dye, and the like.
[0016]
Examples of the fluorescent brightener include stilbene compounds, coumarin compounds, biphenyl compounds, benzoxazoline compounds, naphthalimide compounds, pyrazoline compounds, carbostyril compounds, diaminostilbene disulfonic acid derivatives, imidazole derivatives, Examples include coumarin derivatives, triazole derivatives, carbazole derivatives, pyridine derivatives, naphthalic acid derivatives, imidazolone derivatives, and the like. Among these, stilbene compounds are preferable.
The content of the fluorescent brightener in the base paper is not particularly limited, but is preferably 0.01 to 0.5% by mass, and more preferably 0.02 to 0.2% by mass.
[0017]
Examples of the water-soluble polymer include cationized starch, polyvinyl alcohol, carboxy-modified polyvinyl alcohol, carboxymethyl cellulose, hydroxyethyl cellulose, cellulose sulfate, gelatin, casein, sodium polyacrylate, and styrene-maleic anhydride copolymer sodium salt. And sodium polystyrene sulfonate.
Examples of the water resistant substance include latex emulsions such as styrene-butadiene copolymer, ethylene-vinyl acetate copolymer, polyethylene, vinylidene chloride copolymer, and polyamide polyamine epichlorohydrin.
Examples of the pigment include calcium carbonate, clay, kaolin, talc, barium sulfate, and titanium oxide.
[0018]
The base paper as described above is a ratio (Ea / Eb) of the longitudinal Young's modulus (Ea) and the transverse Young's modulus (Eb) in terms of improving the rigidity and dimensional stability (curlability) of the electrophotographic image receiving paper. ) Is preferably in the range of 1.5 to 2.0. In the range where the Ea / Eb value is less than 1.5 or more than 2.0, the rigidity and curl property of the electrophotographic image-receiving paper are liable to be deteriorated, and the running property during transportation is hindered. Absent.
[0019]
The Oken type smoothness of the surface of the base paper on the toner image-receiving layer side is preferably 210 seconds or more, and more preferably 250 seconds or more. If the Oken type smoothness is less than 210 seconds, the image quality of the toner image becomes poor, which is not preferable. In addition, although an upper limit is not specifically limited, In practice, about 600 seconds are preferable and about 500 seconds are more preferable.
Here, the Oken-type smoothness is measured according to JAPAN TAPPI No. 5 Smoothness defined by the B method.
[0020]
In general, it is known that the “strain” of paper differs based on the difference in the mode of beating. After beating, the elastic force (rate) of the paper made after paper beating is an important indicator of the degree of “strain” of the paper. Can be used as an additional factor. In particular, the elastic modulus of paper is measured by measuring the speed of sound propagating through the paper, using the relationship between the dynamic elastic modulus and density, which indicates the physical properties of the viscoelastic material of the paper, and using an ultrasonic vibration element. Can be obtained from the following equation.
E = ρc²(1-n²)
[E: dynamic elastic modulus, ρ: density, c: speed of sound in paper, n: Poisson's ratio]
[0021]
In the case of normal paper, since n = about 0.2, even if it is calculated by the following formula, it can be calculated without much difference.
E = ρc²
That is, if the density and sound speed of paper can be measured, the elastic modulus can be easily obtained. In the above equation, when measuring the speed of sound, various known devices such as Sonic Tester SST-110 (manufactured by Nomura Corporation) can be used.
[0022]
The density of the base paper is 0.9 g / cm³Above, 0.95 g / cm³Or more, preferably 0.95 to 1.2 g / cm³Is more preferable.
There is no restriction | limiting in particular in the thickness of the said base paper, According to the objective, it can select suitably, Usually, 30-500 micrometers is preferable, 50-300 micrometers is more preferable, 100-250 micrometers is still more preferable. There is no restriction | limiting in particular in the basic weight of the said base paper, According to the objective, it can select suitably, For example, 50-250 g / m²Is preferable, 100-200 g / m²Is more preferable.
[0023]
-Polyolefin resin layer-
As the polyolefin resin layer, for example, a polyolefin resin such as a homopolymer of α-olefin such as polyethylene and polypropylene and a mixture thereof is used. These polyolefin resins are not particularly limited in molecular weight as long as extrusion coating is possible, and can be appropriately selected according to the purpose. Usually, polyolefin resins having a molecular weight in the range of 20,000 to 200,000 are used. Used.
[0024]
There is no restriction | limiting in particular as said polyethylene resin, According to the objective, it can select suitably, For example, high density polyethylene (HDPE), low density polyethylene (LDPE), linear low density polyethylene (L-LDPE), etc. Is mentioned.
For example, the melt index is 5 to 30 g / 10 min, preferably 10 to 20 g / 10 min, and the density is 0.945 g in that the cut surface when cut to a specified size with a cutter or the like in the cutting process is uniform and clean. / Cm³40 to 75 parts by mass of the above high-density polyethylene, a melt index of 1 to 15 g / 10 min, preferably 2 to 10 g / 10 min, and a density of 0.930 g / cm³It is preferable to use a polyethylene resin mixture obtained by mixing 25 to 60 parts by mass of the following low density polyethylene. These resins may be used alone or in combination of two or more.
[0025]
The mixing ratio (HDPE / LDPE) of the high-density polyethylene and the low-density polyethylene is preferably 40 to 75/60 to 25 in terms of mass ratio, and the mass ratio is 50 to 70/50 to 30. It is more preferable. In the support having a polyolefin resin layer coated with a polyethylene mixture in which the high-density polyethylene is 75 parts by mass or more and the low-density polyethylene is less than 25 parts by mass, sufficient cutting characteristics (uniform cutting) Surface) may not be obtained. In addition, in a support having a polyolefin resin layer coated with a polyethylene mixture in which high-density polyethylene is less than 40 parts by mass and low-density polyethylene is 60 parts by mass or more, sufficient cutting characteristics (uniform cut surface) However, it is not preferable because the surface is partially melted by the heating roll at the time of fixing, causing a deterioration in surface properties or a jamming failure due to poor running.
[0026]
When a polyolefin resin layer is provided on both sides of the base paper, it is preferable to coat a polyolefin resin layer made of a polyethylene mixture having the above composition on both sides. Further, the polyolefin resin layer may contain an antistatic agent such as a surfactant or a metal oxide in order to adjust the surface electric resistance, and further serves as both a polyolefin resin layer containing these and a conductive layer. It may be used as a layer.
[0027]
In the present invention, in the case where the polyolefin resin layer is a single layer, in the polyolefin resin layer, in the case where the polyolefin resin layer is a multilayer, in at least one of the layers, a fluorescent whitening agent, blue A white pigment such as titanium dioxide, an antioxidant, and the like can be contained as required. In addition, when this polyolefin resin layer is a multilayer, the tackifier resin, adhesive resin, etc. can also be contained in the lowest layer which contact | connects a base paper from a viewpoint of making adhesiveness with a base paper favorable.
[0028]
In the present invention, at least the polyolefin resin layer on the side where the toner image receiving layer is provided (surface side) of the support contains 0.01 to 0.5% by mass of a fluorescent brightening agent, and 0.01 to 0.2%. It is preferable to contain by mass.
When the content of the fluorescent brightening agent is less than 0.01% by mass, the effect on the whiteness becomes insufficient. On the other hand, if it exceeds 0.5% by mass, bleeding occurs with time, and there is a risk of poor adhesion between the base paper and the polyolefin resin layer.
[0029]
The fluorescent whitening agent is not particularly limited as long as it is a compound that absorbs in the near ultraviolet region and emits fluorescence at 400 to 500 nm, and can be used from known fluorescent whitening agents. Mention may be made of the compounds described in “The Chemistry of Synthetic Dies”, Volume V, Chapter 8, edited by Veen Rataraman. Specifically, stilbene compounds, coumarin compounds, biphenyl compounds, benzoxazoline compounds, naphthalimide compounds, pyrazoline compounds, carbostyryl compounds, diaminostilbene disulfonic acid derivatives, imidazole derivatives, coumarin derivatives, triazole derivatives Carbazole derivatives, pyridine derivatives, naphthalic acid derivatives, imidazolone derivatives, and the like.
Moreover, the fluorescent whitening agent described in JP-A-3-144447 can also be used. In addition, materials described in “New Edition Dye Handbook” (edited by Synthetic Organic Chemistry Association; Maruzen, 1970), “Color Index” (The Society of Dyer's and Colorists), and the like can also be used.
[0030]
As the fluorescent brightening agent, an appropriately synthesized product or a commercially available product may be used. As this commercial item, Sumitomo Chemical white fur fur PSN, PHR, HCS, PCS, B; UVITEX-OB by Ciba-Geigy etc. are mentioned, for example.
[0031]
Further, in the present invention, the polyolefin resin layer on the side of the support on which the toner image-receiving layer is provided (surface side) satisfies the content of the fluorescent brightening agent, and then the bluing agent is added in an amount of 0.01 to 1. .3% by mass, and more preferably 0.05 to 1% by mass.
If the content of the bluing agent is less than 0.01% by mass, the yellowish color is noticeable and the suitability for silver salt photographic like is deteriorated. The aptitude is reduced.
[0032]
The bluing agent is not particularly limited and may be appropriately selected depending on the purpose. Examples thereof include ultramarine blue, cobalt blue, cobalt phosphate phosphate, quinacridone pigments, and mixtures thereof. Of these, ultramarine blue is more preferable. As the ultramarine blue, a mixture of blue ultraviolet and purple ultramarine blue (for example, blue ultramarine blue / purple ultramarine blue (mass ratio) = 1/1 to 1/3) is particularly preferable.
The particle size of the bluing agent is not particularly limited and may be appropriately selected depending on the intended purpose, but is usually preferably in the range of 0.3 to 10 μm.
[0033]
Furthermore, in the present invention, at least the polyolefin resin layer on the side where the toner image-receiving layer is provided (surface side) of the support preferably contains 3 to 30% by mass of white pigment, and preferably 10 to 20% by mass. Is more preferable.
When the content is less than 3% by mass, the light transmittance in the image forming or image fixing material is increased. On the other hand, when it exceeds 30% by mass, handling properties such as cracking and anti-adhesion may be deteriorated. is there.
[0034]
Examples of the white pigment include titanium dioxide, calcium carbonate, barium sulfate, zinc white, kaolin, calcined kaolin, magnesium carbonate, aluminum silicate, calcium silicate, magnesium silicate, and synthetic amorphous silica. Of these, titanium dioxide is preferred because of its high image resolution.
[0035]
Examples of the titanium dioxide include rutile titanium dioxide, anatase titanium dioxide, titanium dioxide that has been surface-coated with an inorganic substance such as alumina-containing treatment, hydrous silicon dioxide treatment, or zinc oxide treatment.
[0036]
The titanium dioxide preferably has a particle surface treated with a silane coupling agent, and the silane coupling agent preferably has an end modified with ethoxy or methoxy. The treatment amount of the silane coupling agent is preferably 0.05 to 2.5% by mass, more preferably 0.5 to 2.0% by mass with respect to titanium dioxide. When the treatment amount of the silane coupling agent is less than 0.05% by mass, the surface treatment effect by the silane coupling agent may not be sufficient, while when it exceeds 2.5% by mass, it is excessive with respect to titanium dioxide. It may be a process.
[0037]
In order to suppress the activity of the titanium dioxide pigment, the surface of the titanium dioxide is preferably subjected to a surface treatment with an inorganic surface treatment agent before the surface treatment of the silane coupling agent. Examples of the inorganic surface treatment agent include Al.₂O₃And SiO₂It is preferable that the treatment amount (calculated in the form of an anhydride) of the inorganic surface treatment agent is 0.01 to 1.8% by mass with respect to titanium dioxide. -1.0 mass% is more preferable.
If the surface of the titanium dioxide is not subjected to an inorganic surface treatment, the heat resistance of the titanium dioxide is low, and the titanium dioxide may turn yellow when used in an extrusion laminate at around 320 ° C. Further, since the activity of titanium dioxide is not suppressed, the titanium dioxide particles are aggregated and caught in a metal filter net equivalent to 20 to 400 mesh which is generally provided in the vicinity of the extrusion laminate outlet to prevent extrusion of foreign matter. May cause an increase in pressure.
On the other hand, when the treatment amount of the inorganic surface treatment agent is 1.8% by mass or more with respect to titanium dioxide, moisture tends to adhere to the surface of the inorganic surface treatment agent, and when used for extrusion lamination, the growth of the die lip stain is remarkably accelerated. There is a case.
[0038]
The titanium dioxide is kneaded such as a metal roll of higher fatty acid, higher fatty acid ethyl, higher fatty acid amide, higher fatty acid, polyolefin wax and the like as a dispersion aid, and a two-roll, three-roll, kneader, Banbury mixer, continuous kneading, etc. And kneaded into the resin. As the dispersion aid, metal stearate is preferable, and zinc stearate is more preferable. The resin thus kneaded with the titanium dioxide pigment is formed into a pellet shape and used as a master batch of the titanium dioxide pigment.
[0039]
The titanium dioxide concentration in the pellet is preferably about 30 to 75% by mass. The concentration of the dispersion aid in the pellet is preferably about 0.5 to 10% by mass. When the titanium dioxide concentration is less than 30% by mass, the bulk of the pellet increases. Conversely, when it exceeds 75% by mass, the dispersibility of the titanium dioxide is deteriorated and the pellet is liable to be cracked. Moreover, it is preferable to dry dry or vacuum dry the masterbatch containing titanium dioxide at 50-90 degreeC for 2 hours or more before use.
The average primary particle diameter of the titanium dioxide is preferably in the range of 0.1 to 1.0 μm.
[0040]
The tackifier resin is appropriately selected from, for example, rosin derivative resins, terpene resins (for example, polymer β-pinene), coumarone-indene resins, petroleum hydrocarbon resins, and the like. These may be used alone or in combination of two or more.
[0041]
Examples of the petroleum hydrocarbon resins include aliphatic petroleum resins, aromatic petroleum resins, dicyclopentadiene petroleum resins, copolymer petroleum resins, hydrogenated petroleum resins, alicyclic petroleum resins, and the like. Is mentioned. As the aliphatic petroleum resin, those having 5 carbon atoms are particularly preferable. As the aromatic petroleum resin, those having 9 carbon atoms are particularly preferable.
[0042]
As a compounding quantity of the said tackifier resin, 0.5-60 mass% is preferable normally with respect to resin which comprises the said polyolefin resin layer, and 10-35 mass% is more preferable. If the blending amount of the tackifier resin is less than 0.5% by mass, adhesion failure may occur. On the other hand, if it exceeds 60% by mass, neck-in during production may easily occur.
[0043]
Examples of the adhesive resin include ionomer, ethylene vinyl acetate copolymer (EVA), ethylene-acrylic acid copolymer, and metal salts thereof. As a compounding quantity of the said adhesive resin, 20-500 mass% is preferable with respect to resin which forms the said polyolefin resin layer, and 50-200 mass% is more preferable. The tackifier resin and the adhesive resin may be used in combination.
[0044]
(Method for producing support for electrophotographic image-receiving sheet)
The polyolefin resin layer is melted by heating and melting the pellet containing the fluorescent brightening agent, bluing agent, titanium dioxide, etc., and if necessary diluted with a resin that forms the polyolefin resin layer, and melted. On the traveled base paper, it is coated by any of the usual laminating method, sequential laminating method, or laminating method using a single-layer or multi-layer extrusion die such as a foot block type, a multi-manifold type, a multi-slot type, or a laminator. Is formed. The shape of the single-layer or multi-layer extrusion die is not particularly limited and may be appropriately selected depending on the intended purpose. In general, a T die, a coat hanger die, and the like are preferable.
[0045]
The base paper is subjected to an activation treatment such as a corona discharge treatment, a flame treatment, a glow discharge treatment, or a plasma treatment before the resin for forming the polyolefin resin layer is coated on one or both surfaces of the base paper. It is preferable to apply.
[0046]
As thickness of the polyolefin-type resin layer formed in the side (surface) in which the image forming layer of the said support is formed, 10-60 micrometers is preferable. On the other hand, the thickness of the polyolefin resin layer formed on the side of the support on which the image forming layer is not formed (back surface) is preferably 10 to 50 μm.
[0047]
In the polyethylene mixture used for the polyolefin resin layer, the mixing method of the high-density polyethylene and the low-density polyethylene is not particularly limited and can be appropriately selected depending on the purpose. For example, using a kneader extruder, a heat kneading roll, a Banbury mixer, a kneader, etc., after adding a predetermined amount of high-density polyethylene and low-density polyethylene and further adding various additives as necessary, these are melt-mixed. A method of pulverizing or pelletizing the mixture, a method of directly feeding in a simply blended state using an extruder, and performing extrusion coating, etc. can be appropriately employed.
[0048]
The surface of the polyolefin resin layer can be subjected to an activation treatment such as a corona discharge treatment or a flame treatment, and after the activation treatment, a subbing treatment as described in JP-A No. 61-84443 is performed. You can also.
[0049]
(Electrophotographic image-receiving sheet)
The electrophotographic image-receiving sheet of the present invention comprises the support for an electrophotographic image-receiving sheet, at least one toner image-receiving layer provided on one side of the support, and at least one back on the other side of the support. A layer is provided. Further, other layers appropriately selected as necessary, for example, surface protective layer, intermediate layer, undercoat layer, cushion layer, reflective layer, tint adjusting layer, storage stability improving layer, adhesion preventing layer, anti-curl layer, smoothing It has a layer. Each of these layers may have a single layer structure or a laminated structure.
[0050]
[Toner image receiving layer]
The toner image receiving layer is a toner image receiving layer for receiving color or black toner and forming an image. The toner image receiving layer receives a toner for forming an image from a developing drum or an intermediate transfer body by (static) electricity, pressure, etc. in a transfer process, and fixes it by heat, pressure, etc. in a fixing process. Have
[0051]
The toner image-receiving layer needs to be a low-transparency toner image-receiving layer having a light transmittance of 78% or less from the viewpoint of making the electrophotographic image-receiving sheet of the present invention feel close to a photograph. Is preferably 73% or less, and more preferably 72% or less.
The light transmittance can be measured by separately forming a coating film having the same thickness on a polyethylene terephthalate film (100 μm) and using the direct reading haze meter (Suga Test Instruments HGM-2DP). .
[0052]
As the material of the toner image-receiving layer, at least a thermoplastic resin is contained, and various additives that are added for the purpose of improving the thermodynamic properties of the toner image-receiving layer as necessary, for example, a release agent, a plasticizer, Contains a colorant, filler, crosslinking agent, charge control agent, emulsion, dispersion and the like.
[0053]
-Thermoplastic resin-
The thermoplastic resin is not particularly limited as long as it is deformable under temperature conditions such as fixing and can accept toner, and can be appropriately selected according to the purpose. For example, it is preferable to use a copolymer resin such as a polyester resin, styrene, or styrene-butyl acrylate, and contains 20% by mass or more of a copolymer resin such as a polyester resin, styrene, or styrene-butyl acrylate. Is more preferable. Further, styrene, styrene-butyl acrylate copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer and the like are more preferable.
[0054]
Examples of the thermoplastic resin include (a) a resin having an ester bond, (b) a polyurethane resin, (c) a polyamide resin, (d) a polysulfone resin, (e) a polyvinyl chloride resin, etc. ) Polyvinyl butyral, (to) polycaprolactone resin, (h) polyolefin resin, and the like.
[0055]
Examples of the resin having an ester bond (b) include terephthalic acid, isophthalic acid, maleic acid, fumaric acid, phthalic acid, adipic acid, sebacic acid, azelaic acid, abietic acid, succinic acid, trimellitic acid, and pyromellitic acid. Dicarboxylic acid components such as acids (these dicarboxylic acid components may be substituted with sulfonic acid groups, carboxyl groups, etc.) and diether derivatives of ethylene glycol, diethylene glycol, propylene glycol, bisphenol A, bisphenol A (for example, Bisphenol A ethylene oxide 2 adducts, bisphenol A propylene oxide 2 adducts, etc.), bisphenol S, 2-ethylcyclohexyldimethanol, neopentyl glycol, cyclohexyldimethanol, glycerin, etc. Polyacrylic acid ester resins such as polyester resins, polymethyl methacrylate, polybutyl methacrylate, polymethyl acrylate, polybutyl acrylate, etc. obtained by condensation with the alcohol component (these alcohol components may be substituted with hydroxyl groups, etc.) Alternatively, polymethacrylic acid ester resin, polycarbonate resin, polyvinyl acetate resin, styrene acrylate resin, styrene-methacrylic acid ester copolymer resin, vinyl toluene acrylate resin, and the like can be given.
Specific examples include those described in JP-A Nos. 59-101395, 63-7971, 63-7972, 63-7773, and 60-294862.
[0056]
Examples of commercially available polyester resins include Toyobo's Byron 290, Byron 200, Byron 280, Byron 300, Byron 103, Byron GK-140, Byron GK-130; Kao's Tufton NE-382, Tufton U- 5, ATR-2009, ATR-2010; Elitel UE3500, UE3210, XA-8153 manufactured by Unitika; Polyester TP-220, R-188 manufactured by Nippon Synthetic Chemical Co., Ltd.
Commercially available products of the acrylic resin include Mitsubishi Rayon Co., Ltd. Dianal SE-5437, SE-5102, SE-5377, SE-5649, SE-5466, SE-5482, HR-169, 124, HR-1127. , HR-116, HR-113, HR-148, HR-131, HR-470, HR-634, HR-606, HR-607, LR-1065, 574, 143, 396, 637, 162, 469, 216 , BR-50, BR-52, BR-60, BR-64, BR-73, BR-75, BR-77, BR-79, BR-80, BR-83, BR-85, BR-87, BR -88, BR-90, BR-93, BR-95, BR-100, BR-101, BR-102, BR-105, BR-106, BR-107, BR- 08, BR-112, BR-113, BR-115, BR-116, BR-117; Sreck P SE-0020, SE-0040, SE-0070, SE-0100, SE-1010, SE- manufactured by Sekisui Chemical Co., Ltd. 1035; Sanyo Chemical Industries Himer ST95, ST120; FM601 manufactured by Mitsui Chemicals.
[0057]
Examples of the (e) polyvinyl chloride resin include polyvinylidene chloride resin, vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl propionate copolymer resin, and the like.
Examples of the (f) polyvinyl butyral include cellulose resins such as polyol resin, ethyl cellulose resin, and cellulose acetate resin. Examples of commercially available products include those manufactured by Denki Kagaku Kogyo Co., Ltd. and Sekisui Chemical Co., Ltd. The polyvinyl butyral has a polyvinyl butyral content of 70% by mass or more, an average polymerization degree of 500 or more is preferable, an average polymerization degree of 1000 or more is more preferable, and a commercially available product is Denka Butyral manufactured by Denki Kagaku Kogyo Co. 3000-1, 4000-2, 5000A, 6000C; manufactured by Sekisui Chemical Co., Ltd. S-REC BL-1, BL-2, BL-3, BL-S, BX-L, BM-1, BM-2, BM-5 , BM-S, BH-3, BX-1, BX-7, and the like.
Examples of the (g) polycaprolactone resin include styrene-maleic anhydride resin, polyacrylonitrile resin, polyether resin, epoxy resin, phenol resin, and the like.
Examples of the (h) polyolefin resin include polyethylene resins, polypropylene resins, copolymer resins of olefins such as ethylene and propylene and other vinyl monomers, acrylic resins, and the like.
[0058]
The said thermoplastic resin may be used individually by 1 type, may be 2 or more types, In addition to these, these mixtures, these copolymers, etc. can also be used.
[0059]
The thermoplastic resin is preferably one that can satisfy the following properties of the toner image-receiving layer in the state where the toner image-receiving layer is formed, more preferably one that can satisfy the above-mentioned properties of the toner image-receiving layer even with the resin alone. It is also preferable to use two or more resins having different layer properties.
[0060]
As the thermoplastic resin, those having a larger molecular weight than the thermoplastic resin used in the toner are preferable. However, the molecular weight described above is not necessarily preferable depending on the relationship between the thermodynamic properties of the thermoplastic resin used in the toner and the resin used in the toner image-receiving layer. For example, when the softening temperature of the resin used in the toner image receiving layer is higher than that of the thermoplastic resin used in the toner, the molecular weight is the same or the resin used in the toner image receiving layer is the same. Smallness may be preferred.
[0061]
It is also preferable to use a mixture of resins having the same composition and different average molecular weights as the thermoplastic resin. Further, as the relationship with the molecular weight of the thermoplastic resin used in the toner, the relationship disclosed in JP-A-8-334915 is preferable.
The molecular weight distribution of the thermoplastic resin is preferably wider than the molecular weight distribution of the thermoplastic resin used in the toner.
Examples of the thermoplastic resin include JP-B-5-127413, JP-A-8-194394, JP-A-8-334915, JP-A-8-334916, JP-A-9-171265, and JP-A-10. Those satisfying the physical properties disclosed in the publication No. 221877 / etc. Are preferred.
[0062]
The thermoplastic resin used for the toner image-receiving layer is particularly preferably an aqueous resin such as a water-soluble resin or a water-dispersible resin for the following reasons (i) to (ii).
(I) The organic solvent is not discharged in the coating and drying process, and is excellent in environmental suitability and work suitability.
(Ii) Many release agents such as wax are difficult to dissolve in a solvent at room temperature, and are often dispersed in a solvent (water, organic solvent) in advance. Further, the water dispersion form is more stable and more suitable for the production process. Furthermore, the water-based coating is more likely to cause the wax to bleed onto the surface during the coating and drying process, and the effects of the release agent (offset resistance, adhesion resistance, etc.) can be easily obtained.
[0063]
As the water-based resin, if it is a water-soluble resin or a water-decomposable resin, its composition, bond structure, molecular structure, molecular weight, molecular weight distribution, and form are not specified. Examples of the water-based group of the polymer include a sulfonic acid group, a hydroxyl group, a carboxylic acid group, an amino group, an amide group, or an ether group.
Examples of the water-soluble resin include Research Disclosure No. 17,643, page 26, No. 18,716, page 651, No. 307,105, pages 873-874, and JP-A No. 64-13546. 71) to those described on pages (75) to (75).
Specifically, for example, vinylpyrrolidone-vinyl acetate copolymer, styrene-vinylpyrrolidone copolymer, styrene-maleic anhydride copolymer, water-soluble polyester, water-soluble acrylic, water-soluble polyurethane, water-soluble nylon, water-soluble An epoxy resin can be used. Further, the gelatin may be selected from so-called demineralized gelatin in which the content of lime-processed gelatin, acid-processed gelatin, calcium, or the like is reduced in accordance with various purposes, and is preferably used in combination. Commercially available plus coats manufactured by Teraoh Chemical Co., Ltd. as water-soluble polyesters; Finetex ES series manufactured by Dainippon Ink &Chemicals; Jurimer AT series manufactured by Nippon Pure Chemical as water-soluble acrylics; Tex 6161, K-96; Seiko Chemical Industries high loss NL-1189, BH-997L, and the like.
[0064]
Examples of water-dispersible resins include water-dispersed resins such as water-dispersed acrylic resins, water-dispersed polyester resins, water-dispersed polystyrene resins, and water-dispersed urethane resins; acrylic resin emulsions, polyvinyl acetate emulsions, and SBR (styrene / butadiene). -Rubber) Emulsions such as emulsions, resins and emulsions in which the thermoplastic resins (a) to (h) above are dispersed in water, or their copolymers, mixtures, and cationically modified ones are appropriately selected. Two or more types can be combined.
Commercially available products of the water-dispersible resin include, for example, Toyobo's Bironal series, Takamatsu Yushi pesresin A series, Kao Tufton UE series, Nippon Synthetic Polyester WR series, Unitika Eliere series, and acrylic series. Then, high loss XE, KE, PE series manufactured by Seiko Chemical Industry, Jurimer ET series manufactured by Nippon Pure Chemical Co., Ltd. and the like can be mentioned.
The film formation temperature (MFT) of the polymer used is preferably room temperature or higher for storage before printing, and preferably 100 ° C. or lower for fixing of toner particles.
[0065]
The content of the thermoplastic resin is preferably 50% by mass or more, and more preferably 50 to 90% by mass with respect to the total amount of the toner image-receiving layer.
[0066]
The thickness of the toner image-receiving layer is suitably ½ or more, preferably 1 to 3 times the particle diameter of the toner used. The toner image receiving layer preferably has a thickness disclosed in JP-A-5-216322 and JP-A-7-301939. Specifically, the thickness of the toner image receiving layer is, for example, preferably 1 to 50 μm, and more preferably 5 to 15 μm.
[0067]
-Release agent-
The release agent of the present invention is blended in the toner image receiving layer in order to prevent offset of the toner image receiving layer. The release agent used in the present invention is heated and melted at the fixing temperature, deposited on the surface of the toner image-receiving layer, unevenly distributed on the surface of the toner image-receiving layer, and further cooled and solidified to be released onto the surface of the toner image-receiving layer. The type is not limited as long as it forms a layer of the mold material.
Examples of the release agent exhibiting such effects include at least one release agent selected from the group consisting of silicone compounds, fluorine compounds, waxes, and matting agents. Preferably, at least one release agent selected from the group consisting of silicone oil, polyethylene wax, carnauba wax, and silicone particles and polyethylene wax particles is used.
[0068]
As the mold release agent, for example, compounds described in “Summary of properties and applications of revised wax” by Kosho Shobo and the Silicone Handbook published by Nikkan Kogyo Shimbun, Inc. can be used. JP-B-59-38581, JP-B-4-32380, Patent Nos. 2838498, 2949558, JP-A-50-117433, 52-52640, 57-148755, 61-62056. 61-62057, 61-118760, JP-A-2-42451, 3-41465, 4-212175, 4-214570, 4-263267, 5-34966, 5-119514, 6-59502, 6-161150, 6-175396, 6-219040, 6-230600, 6-295093, 7-36210, 7 -43940, 7-56387, 7-56390, 7-64335, 7-199682, 7-223362 7-287413, 8-184992, 8-227180, 8-248671, 8-248799, 8-248801, 8-278663, 9-152939, 9 -160278, 9-185181, 9-319139, 9-319143, 10-20549, 10-48889, 10-198069, 10-207116, 11-2917 No. 11-44969, No. 11-65156, No. 11-73049, No. 11-194542, and the silicone compounds, fluorine compounds, and waxes used in the toners are also preferably used. . Further, a plurality of these compounds can be used in combination.
[0069]
Specifically, as the silicone compound, unmodified silicone oil as silicone oil (specifically, dimethylsiloxane oil, methyl hydrogen silicone oil, phenylmethyl silicone oil, commercially available KF-96 manufactured by Shin-Etsu Chemical Co., Ltd.) KF-96L, KF-96H, KF-99, KF-50, KF-54, KF-56, KF-965, KF-968, KF-994, KF-995, HIVAC F-4, F-5; Toray Dow Corning Silicone SH200, SH203, SH490, SH510, SH550, SH710, SH704, SH705, SH7028A, SH7036, SM7060, SM7001, SM7706, SH7036, SH8710, SH1107, SH8627; Toshiba Silicone TSF400, TSF401, TSF404, TSF405, TSF431, TSF433, TSF434, TSF437, TSF450 series, TSF451 series, TSF456, TSF458 series, TSF483, TSF484, TSF4045, TSF4300, TSF4600, YF33 series, YF-3057, YF-3057 3802, YF-3804, YF-3807, YF-3897, XF-3905, XS69-A1753, TEX100, TEX101, TEX102, TEX103, TEX104, TSW831, etc., amino-modified silicone oil (KF manufactured by Shin-Etsu Chemical Co., Ltd. as a commercial product) -857, KF-858, KF-859, KF-861, KF-864, KF-880, Toray Dowconi SF8417, SM8709 made by Ning Silicone, TSF4700, TSF4701, TSF4702, TSF4703, TSF4704, TSF4705, TSF4706, TEX150, TEX151, TEX154, etc. made by Toshiba Silicone, carboxy-modified silicone oil (Toray Dow Corning Silicone BY16- as a commercial product) 880, Toshiba Silicone TSF4770, XF42-A9248, etc.), carbinol modified silicone oil (Toshiba Silicone XF42-B0970 etc. as a commercial product), vinyl modified silicone oil (Toshiba Silicone XF40-A1987 etc. as a commercial product), epoxy modified Silicone oil (Toray Dow Corning Silicone SF8411, SF8413 as a commercial product; Toshiba Silico TSF3965, TSF4730, TSF4732, XF42-A4439, XF42-A4438, XF42-A5041, XC96-A4462, XC96-A4463, XC96-A4464, TEX170, etc., polyether-modified silicone oil (KF made by Shin-Etsu Chemical) -351 (A), KF-352 (A), KF-353 (A), KF-354 (A), KF-355 (A), KF-615 (A), KF-618, KF-945 (A ); Toray Dow Corning Silicone SH3746, SH3771, SF8421, SF8419, SH8400, SF8410; Toshiba Silicone TSF4440, TSF4441, TSF4445, TSF4446, TSF4450, TSF4452, TSF4453, SF4460), silanol-modified silicone oil, methacryl-modified silicone oil, mercapto-modified silicone oil, alcohol-modified silicone oil (Toray Dow Corning Silicone SF8427, SF8428, Toshiba Silicone TSF4750, TSF4751, XF42-B0970, etc.) , Alkyl-modified silicone oils (Toray Dow Corning Silicone SF8416, Toshiba Silicone TSF410, TSF411, TSF4420, TSF4421, TSF4422, TSF4450, XF42-334, XF42-A3160, XF42-A3161, etc.), fluorine-modified silicone Oil (commercially available FS1265 made by Toray Dow Corning Silicone, Toshiba Silicone FQF501, etc.), silicone rubber and silicone fine particles (Toray Dow Corning Silicone SH851U, SH745U, SH55UA, SE4705U, SH502UA & B, SRX539U, SE6770U-P, DY38-038, DY38-047, Trefill F-201, F-202, F-250, R-900, R-902A, E-500, E-600, E-601, E-506, BY29-119; Toshiba Silicone Tospearl 105, 120, 130, 145, 240, 3120), silicone-modified resins (specifically, olefin resins, polyester resins, vinyl resins, polyamide resins, cellulose resins, phenoxy resins, vinyl chloride-vinyl acetate resins, urethane resins, acrylic resins, styrene resins) Dairy Seika's Dialomer SP203V, SP712, SP2105, SP3023; Nippon Oil & Fats Modiper FS700, FS710, FS720, FS730, FS770; Toa Gosei Chemical Co., Ltd. Symac US-270, US-350, US-352, US-380, US-413, US-450, Reseda GP-705, GS-30, GF-150, GF-300; SH997 manufactured by Toray Dow Corning Silicone SR2114, SH2104, SR2115, SR2202, DCI-2577, SR2317, SE4001U, SRX625B, SRX643, SRX439U, SRX488U, SH804, SH840, SR2107, SR2115; YR3370, TSR1122, TSR102, TSR108, TSR116, TSR117, TSR125A, TSR127B, TSR144, TSR180, TSR187, YR47, YR3187, YR3224, YR3232, YR3270, YR3340, TE2173, TE2 , Reactive silicone compounds (specifically, there are addition reaction type, peroxide curable type, ultraviolet curable type, and TSR1500, TSR1510, TSR1511, TSR1515, TSR1520, YR3286, YR3340, PSA6574, manufactured by Toshiba Silicones as commercially available products. TPR6500, TPR6501, TPR6600, TPR6702, TPR6604, TP R6700, TPR6701, TPR6705, TPR6707, TPR6708, TPR6710, TPR6712, TPR6721, TPR6722, UV9300, UV9315, UV9425, UV9430, XS56-A2775, XS56-A2982, XS56-A3075, XS56-A3957, XS56S30X80 XS56-B1794, SL6100, SM3000, SM3030, SM3200, YSR3022, and the like.
[0070]
Examples of the fluorine compound include fluorine oil (Daikin Industries # 1, # 3, # 10, # 20, # 50, # 100, Unidyne TG-440, TG-452, TG-490, TG-560 as commercial products. TG-561, TG-590, TG-652, TG-670U, TG-991, TG-999, TG-3010, TG-3020, TG-3510; TF-100, MF-110, MF manufactured by Tochem Products -120, MF-130, MF-160, MF-160E; Asahi Glass Surflon S-111, S-112, S-113, S-121, S-131, S-132, S-141, S-145; FC-430, FC-431 made by Mitsui Fluorochemical, etc.), fluoro rubber (LS63U made by Toray Dow Corning Silicone as a commercial product) Fluorine-modified resin (Nippon Yushi Modiper F200, F220, F600, F2020, F3035; Dainippon Chemical Dialomer FF203, FF204; Asahi Glass Surflon S-381, S-383, S-393, SC- 101, SC-105, KH-40, SA-100; EF-351, EF-352, EF-801, EF-802, EF-601, TFE, TFEA, TFEMA, PDFOH manufactured by Tochem Products; THV manufactured by Sumitomo 3M -200P, etc.), fluorine sulfonic acid compounds (commercially available products EF-101, EF-102, EF-103, EF-104, EF-105, EF-112, EF-121, EF-122A, EF manufactured by Tochem Products) -122B, EF-122C, EF-123A, EF-123B, E -125M, EF-132, EF-135M, EF-305, FBSA, KFBS, LFBS, etc., fluorosulfonic acid, fluorinated acid compounds and salts (specifically, hydrofluoric acid, dilute hydrofluoric acid, borofluoric acid, borofluoride) Zinc, nickel borofluoride, tin borofluoride, lead borofluoride, copper borofluoride, silicic acid, potassium fluoride titanate, perfluorocaprylic acid, ammonium perfluorooctanoate, etc., inorganic fluoride (specifically fluoride) Aluminum, potassium silicofluoride, potassium fluoride zirconate, zinc fluoride tetrahydrate, calcium fluoride, lithium fluoride, barium fluoride, tin fluoride, potassium fluoride, acidic potassium fluoride, magnesium fluoride, fluoride Titanic acid, zirconic fluoride, ammonium hexafluorophosphate, potassium hexafluorophosphate Etc.).
[0071]
Examples of the wax include synthetic hydrocarbons, modified waxes, hydrogenated waxes, and natural waxes.
[0072]
Examples of the synthetic hydrocarbon include polyethylene wax (as commercially available products Polylon A, 393, H-481, manufactured by Chukyo Yushi Co., Ltd., Sanyo Kasei Sun Wax E-310, E-330, E-250P, LEL-250, LEL-800, LEL-400P, etc.), polypropylene wax (commercially available Sanyo Chemical Co., Ltd. Biscol 330-P, 550-P, 660-P), Fischer-Tropsch wax (commercially available products such as FT100, FT-0070 manufactured by Nippon Seiki) Amide compound or acid imide compound (specifically stearic acid amide, phthalic anhydride imide, etc., commercially available products such as Chukyo Yushi Cellosol 920, B-495, Hymicron G-270, G-110, Hydrin D-757, etc. ) And the like.
[0073]
Examples of the modified wax include amine-modified polypropylene (QN-7700 manufactured by Sanyo Chemical Co., Ltd. as a commercial product), acrylic acid-modified or fluorine-modified, olefin-modified wax, and urethane-type wax (NPS-6010 and HAD-5090 manufactured by Nippon Seiki as commercial products). Etc.), alcohol type waxes (NPS-9210, NPS-9215, OX-1949, XO-020T, etc., manufactured by Nippon Seiki) and the like.
[0074]
Examples of the hydrogenated wax include hydrogenated castor oil (as a commercial product, castor wax from Ito Oil Co., Ltd.), castor oil derivatives (dehydrated castor oil DCO, DCO Z-1, DCO Z-3, castor oil fatty acid from Ito Oil as commercial products). CO-FA, ricinoleic acid, dehydrated castor oil fatty acid DCO-FA, dehydrated castor oil fatty acid epoxy ester D-4 ester, castor oil-based urethane acrylate CA-10, CA-20, CA-30, castor oil derivative MINERASOL S-74 , S-80, S-203, S-42X, S-321, special castor oil-based condensed fatty acid MINERASOLRC-2, RC-17, RC-55, RC-335, special castor oil-based condensed fatty acid ester MINERASOL LB-601 , LB-603, LB-604, LB-702, LB-70 , # 11, L-164, etc.), stearic acid (such as 12-hydroxystearic acid made by Ito Oil as a commercial product), lauric acid, myristic acid, palmitic acid, behenic acid, sebacic acid (made by Ito Oil as commercial products) Sebacic acid, etc.), undecylenic acid (such as undecylenic acid made by Ito Oil as a commercial product), heptylic acid (such as heptyl acid from Ito Oil as a commercial product), maleic acid, highly maleated oil (made by Ito Oil as a commercial product) HIMALIN DC-15, LN-10, 00-15, DF-20, SF-20, etc.), blown oil (commercially available from Celonol # 10, # 30, # 60, R-40, S-40 manufactured by Ito Oil) 7), synthetic waxes such as cyclopentadiened oil (CP oil, CP oil-S, etc. made by Ito Oil as commercial products) That.
[0075]
The natural wax is preferably at least one selected from vegetable wax, animal wax, mineral wax and petroleum wax.
[0076]
Examples of the plant wax include carnauba wax (Nippon Seiki EMUSTAR-0413, Chukyo Yushi Cellosol 524, etc. as commercial products), castor oil (commercially available Ito Oil refined castor oil, etc.), rapeseed oil, large Examples include bean oil, wax, cotton wax, rice wax, sugarcane wax, candelilla wax, Japan wax, jojoba oil, and the like. Among these, in particular, it has an excellent offset resistance, adhesion resistance, paper permeability, glossiness, is resistant to cracking, and can provide an electrophotographic image-receiving sheet capable of forming a high-quality image. Is particularly preferably a carnauba wax having a temperature of 70 to 95 ° C.
Examples of the animal wax include lanolin, spermaceti, stew wax (whale oil), and wool wax.
[0077]
Examples of the mineral wax include, for example, montan wax, montan ester wax, ozokerite, ceresin, fatty acid ester (commercially available products are Sansizer DOA, AN-800, DINA, DIDA, DOZ, DOS, TOTM, TITM manufactured by Shin Nippon Rika). , E-PS, nE-PS, E-PO, E-4030, E-6000, E-2000H, E-9000H, TCP, C-1100, etc.). Among these, in particular, it has an excellent anti-offset property, anti-adhesion property, paper passing property, glossiness, is resistant to cracking, and can provide an electrophotographic image-receiving sheet capable of forming a high-quality image. Is particularly preferably a montan wax of carnauba wax having a temperature of 70 to 95 ° C.
[0078]
Examples of the petroleum wax include paraffin wax (paraffin wax 155, 150, 140, 135, 130, 125, 120, 115, HNP-3, HNP-5, HNP-9, HNP- 10, HNP-11, HNP-12, HNP-14G, SP-0160, SP-0145, SP-1040, SP-1035, SP-3040, SP-3035, NPS-8070, NPS-L-70, OX- 2151, OX-2251, EMUSTAR-0384, EMUSTAR-0136, Chukyo Oil & Fats Cellosol 686, 428, 651-A, A, H-803, B-460, E-172, 866, K-133, Hydrin D-337 E-139, 125 ° paraffin, 125 ° FD, 130 ° Fins, 135 ° paraffin, 135 ° H, 140 ° paraffin, 140 ° N, 145 ° paraffin, paraffin wax M, etc., microcrystalline wax (commercially available from Nihon Seiki Hi-Mic-2095, Hi-Mic-3090) , Hi-Mic-1080, Hi-Mic-1070, Hi-Mic-2065, Hi-Mic-1045, Hi-Mic-2045, EMUSTAR-0001, EMUSTAR-042X, Chukyo Oil & Fats Cellosol 967, M, Nisseki Mitsubishi Petroleum (manufactured by Nippon Seiki OX-1749, OX-0450, OX-0650B, OX-0153, OX-261BN, OX-0551, OX-0550, OX) -0750B, JP- 500, JP-056R, such as JP-011P) and the like.
[0079]
Content (g / m) of the natural wax in the toner image-receiving layer (surface)²) As 0.1 to 4 g / m²Is preferably 0.2 to 2 g / m²Is preferred.
The content is 0.1 g / m²If it is less than 4 g / m, the offset resistance and adhesion resistance may be particularly insufficient.²If it exceeds 1, the amount of wax is too large, and the image quality of the formed image may be inferior.
The melting point (° C.) of the natural wax is preferably 70 to 95 ° C., more preferably 75 to 90 ° C., particularly in terms of offset resistance and paper passing properties.
[0080]
Examples of the matting agent include various known ones. Solid particles used as a matting agent can be classified into inorganic particles and organic particles. Specific examples of the material for the inorganic matting agent include oxides (for example, silicon dioxide, titanium oxide, magnesium oxide, aluminum oxide), alkaline earth metal salts (for example, barium sulfate, calcium carbonate, magnesium sulfate), halogens Examples include silver halide (eg, silver chloride, silver bromide) and glass.
[0081]
Examples of the inorganic matting agent include West German Patent 2529321, British Patent 760775, 1260772, U.S. Patent 1201905, 2192241, 3030562, 3030649, 3257206, 3322555, and 3353958. No. 3,370,951, No. 3,411,907, No. 3,437,484, No. 3523022, No. 3,615,554, No. 3,635,714, No. 3769020, No. 40212245, and No. 4029504.
[0082]
The material of the organic matting agent includes starch, cellulose ester (for example, cellulose acetate propionate), cellulose ether (for example, ethyl cellulose) and synthetic resin. The synthetic resin is preferably water-insoluble or poorly water-soluble. Examples of water-insoluble or poorly water-soluble synthetic resins include, for example, poly (meth) acrylic acid esters (for example, polyalkyl (meth) acrylate, polyalkoxyalkyl (meth) acrylate, polyglycidyl (meth) acrylate), poly (meth) acrylate, (Meth) acrylamide, polyvinyl ester (eg, polyvinyl acetate), polyacrylonitrile, polyolefin (eg, polyethylene), polystyrene, benzoguanamine resin, formaldehyde condensation polymer, epoxy resin, polyamide, polycarbonate, phenol resin, polyvinyl carbazole, polyvinylidene chloride, Etc.
You may use the copolymer which combined the monomer used for the above polymer.
[0083]
In the case of the copolymer, a small amount of hydrophilic repeating units may be contained. Examples of the monomer forming the hydrophilic repeating unit include acrylic acid, methacrylic acid, α, β-unsaturated dicarboxylic acid, hydroxyalkyl (meth) acrylate, sulfoalkyl (meth) acrylate and styrene sulfonic acid.
Examples of the organic matting agent include British Patent No. 1055713, U.S. Pat. Nos. 1,939,213, 2221873, 2268661, 2322037, 2376005, 2391181, 2701245, 2992101, and 3079257. Nos. 3,262,782, 3,443,946, 3,516,832, 3,539,344, 3,591,379, 3,754,924, 3,767,448, JP-A-49-106821, JP-A-57-14835 Are described in the above.
Two or more kinds of solid particles may be used in combination. The average particle size of the solid particles is, for example, preferably 1 to 100 μm, and more preferably 4 to 30 μm. The amount of solid particles used is 0.01 to 0.5 g / m.²Is preferred, 0.02-0.3 g / m²Is more preferable.
[0084]
As the release agent added to the toner image-receiving layer of the present invention, these derivatives, oxides, purified products, and mixtures can also be used. Moreover, these may have a reactive substituent.
[0085]
The melting point (° C.) of the release agent is preferably 70 to 95 ° C., and more preferably 75 to 90 ° C., particularly in terms of offset resistance and paper passing properties.
The release agent is preferably a water-dispersed release agent, particularly in terms of compatibility when an aqueous thermoplastic resin is used as the thermoplastic resin of the toner image-receiving layer.
[0086]
The content of the release agent is preferably 0.1 to 10% by mass, more preferably 0.3 to 8.0% by mass, and further 0.5 to 5.0% by mass with respect to the total amount of the toner image-receiving layer. preferable.
[0087]
-Plasticizer-
As the plasticizer, known plasticizers for resins can be used without particular limitation. The plasticizer has a function of adjusting the flow or softening of the toner image-receiving layer by heat and / or pressure when fixing the toner.
Examples of the plasticizer include "Chemical Handbook" (edited by the Chemical Society of Japan, Maruzen), "Plasticizer -Theory and Application-" (written by Koichi Murai, Koshobo), "Research on plasticizer" “Lower” (edited by Polymer Chemistry Association), “Handbook Rubber / Plastic Compounded Chemicals” (edited by Rubber Digest Co., Ltd.), etc.
[0088]
Some of the plasticizers are described as high-boiling organic solvents or thermal solvents. For example, JP-A-59-83154, 59-178451, 59-178453, and 59-178454. 59-178455, 59-178457, 62-174754, 62-245253, 61-209444, 61-200538, 62-8145, 62-9348, 62-30247, 62-136646, 62-174754, 62-245253, 61-209444, 61-200538, 62-8145, 62-9348, 62- Esters such as those described in publications such as 30247, 62-136646, and JP-A-2-235694 (examples) For example, phthalic acid esters, phosphoric acid esters, fatty acid esters, abietic acid esters, adipic acid esters, sebacic acid esters, azelaic acid esters, benzoic acid esters, butyric acid esters, epoxidized fatty acid esters , Glycolic acid esters, propionic acid esters, trimellitic acid esters, citric acid esters, sulfonic acid esters, carboxylic acid esters, succinic acid esters, maleic acid esters, fumaric acid esters, phthalic acid esters And stearic acid esters), amides (for example, fatty acid amides, sulfoamides, etc.), ethers, alcohols, lactones, polyethyleneoxy compounds and the like.
The plasticizer can be used by mixing with a resin.
[0089]
A relatively low molecular weight polymer can be used as the plasticizer. In this case, the molecular weight of the plasticizer is preferably lower than the molecular weight of the binder resin to be plasticized, and the molecular weight is preferably 15000 or less, more preferably 5000 or less. In the case of a polymer plasticizer, the polymer is preferably the same type as the binder resin to be plasticized. For example, a low molecular weight polyester is preferable for plasticizing a polyester resin. Furthermore, oligomers can also be used as plasticizers. In addition to the compounds listed above, commercially available products include, for example, Adeka Sizer PN-170, PN-1430 manufactured by Asahi Denka Kogyo; P. HALL products PARAPLEX-G-25, G-30, G-40; Rika Hercules products Ester gum 8L-JA, Ester R-95, Pentaline 4851, FK115, 4820, 830, Louisol 28-JA, Picolastic A75, Pico Examples include Tex LC and Crystallex 3085.
[0090]
The plasticizer relieves stress and strain (physical strain such as elastic force and viscosity, strain due to mass balance of molecules, binder main chain, pendant, etc.) generated when toner particles are embedded in the toner image receiving layer. Can be used arbitrarily to
The plasticizer may be in a micro-dispersed state in the toner image-receiving layer, may be in a phase-separated microscopically in a sea-island shape, or may be in a sufficiently mixed and dissolved state with other components such as a binder.
The content of the plasticizer in the toner image-receiving layer is preferably 0.001 to 90% by mass, more preferably 0.1 to 60% by mass, and still more preferably 1 to 40% by mass.
The plasticizer adjusts smoothness (improves transportability due to reduced frictional force), improves fixing unit offset (detachment of toner and layers from the fixing unit), adjusts curl balance, and adjusts charging (toner electrostatic image It may be used for the purpose of forming).
[0091]
-Colorant-
Examples of the colorant include fluorescent whitening agents, white pigments, colored pigments, and dyes.
The fluorescent whitening agent is a compound that absorbs in the near ultraviolet region and emits fluorescence at 400 to 500 nm, and various known fluorescent whitening agents can be used without particular limitation. Examples of the optical brightener include K.I. Preferable examples include the compounds described in “The Chemistry of Synthetic Dies” edited by Veen Rataraman, Vol. Specific examples include stilbene compounds, coumarin compounds, biphenyl compounds, benzoxazoline compounds, naphthalimide compounds, pyrazoline compounds, carbostyryl compounds, and the like. Examples thereof include white fur fur PSN, PHR, HCS, PCS, B manufactured by Sumitomo Chemical; UVITEX-OB manufactured by Ciba-Geigy.
[0092]
As the white pigment, an inorganic pigment (for example, titanium oxide, calcium carbonate, etc.) in the filler section described later can be used. Examples of colored pigments include various pigments and azo pigments described in JP-A-63-44653 (for example, azo lake; carmine 6B, red 2B, insoluble azo; monoazo yellow, disazo yellow, pyrazolo orange, vulcan orange, condensation) Azo series; chromophthal yellow, chromophthal red), polycyclic pigments (for example, phthalocyanine series; copper phthalocyanine blue, copper phthalocyanine green, dioxazine series; dioxazine violet, isoindolinone series; isoindolinone yellow, slen series; Perylene, perinone, flavantron, thioindigo, lake pigment (eg, malachite green, rhodamine B, rhodamine G, Victoria blue B) or inorganic pigment (eg, oxide, titanium dioxide, bengara, sulfate; precipitated barium sulfate) Calcium precipitated carbonates, silicates; carbonates hydrous silicates, anhydrous silicates, metal powders; aluminum powder, bronze powder, zinc powder, carbon black, chrome yellow, Prussian blue and the like.
These may be used alone or in combination of two or more. Among these, titanium oxide is particularly preferable as the pigment.
[0093]
Various known dyes can be used as the dye.
Examples of oil-soluble dyes include anthraquinone compounds and azo compounds.
Specific examples of water-insoluble dyes include C.I. I. Vat violet 1, C.I. I. Vat violet 2, C.I. I. Vat violet 9, C.I. I. Vat violet 13, C.I. I. Vat violet 21, C.I. I. Vat Blue 1, C.I. I. Vat Blue 3, C.I. I. Vat Blue 4, C.I. I. Vat Blue 6, C.I. I. Vat Blue 14, C.I. I. Vat Blue 20, C.I. I. Vat dyes such as Vat Blue 35; I. Dispers Violet 1, C.I. I. Disperse Violet 4, C.I. I. Disperse Violet 10, C.I. I. Disperse Blue 3, C.I. I. Disperse Blue 7, C.I. I. Disperse dyes such as Disperse Blue 58; I. Solvent Violet 13, C.I. I. Solvent Violet 14, C.I. I. Solvent Violet 21, C.I. I. Solvent Violet 27, C.I. I. Solvent Blue 11, C.I. I. Solvent Blue 12, C.I. I. Solvent Blue 25, C.I. I. And oil-soluble dyes such as Solvent Blue 55.
A colored coupler used in silver salt photography can also be preferably used.
[0094]
Content of the colorant in the toner image receiving layer (surface) (g / m²) As 0.1 to 8 g / m²Is preferably 0.5 to 5 g / m²Is more preferable.
The content of the colorant is 0.1 g / m²If it is less than 1, the light transmittance in the toner image-receiving layer is increased, while the colorant content is 8 g / m.²Exceeding may cause poor handling such as cracking and adhesion resistance.
[0095]
-Filler-
As said filler, an organic or inorganic filler is mentioned, A well-known thing can be used as a reinforcing agent for binder resin, a filler, and a reinforcing material. The filler should be selected with reference to "Handbook Rubber / Plastic Compounding Chemicals" (edited by Rubber Digest Co., Ltd.), "New Edition Plastic Compounding Agent Fundamentals and Applications" (Taiseisha), "Filler Handbook" (Taiseisha), etc. Can do.
Moreover, various inorganic fillers (or pigments) can be used as the filler. Examples of the inorganic pigment include silica, alumina, titanium dioxide, zinc oxide, zirconium oxide, mica-like iron oxide, white lead, lead oxide, cobalt oxide, strontium chromate, molybdenum pigment, smectite, magnesium oxide, calcium oxide, carbonic acid Examples include calcium and mullite. As the filler, silica and alumina are particularly preferable. These fillers may be used alone or in combination of two or more. The filler preferably has a small particle size. If the particle size is large, the surface of the toner image-receiving layer tends to be roughened.
[0096]
The silica includes spherical silica and amorphous silica. The silica can be synthesized by a dry method, a wet method, or an airgel method. The surface of the hydrophobic silica particles may be surface-treated with a trimethylsilyl group or silicone. As silica, colloidal silica is preferable. The average particle diameter of silica is preferably 200 to 5000 nm.
The silica is preferably porous. The average pore diameter of the porous silica is preferably 4 to 120 nm, and more preferably 4 to 90 nm. The average pore volume per mass of the porous silica is preferably 0.5 to 3 ml / g.
[0097]
The alumina includes anhydrous alumina and alumina hydrate. As the crystal form of anhydrous alumina, α, β, γ, δ, ζ, η, θ, κ, ρ, or χ can be used. Alumina hydrate is preferred over anhydrous alumina. As the alumina hydrate, a monohydrate or a trihydrate can be used. Monohydrates include pseudoboehmite, boehmite and diaspore. Trihydrates include dibsite and bayerite. The average particle diameter of the alumina is preferably 4 to 300 nm, and more preferably 4 to 200 nm. Alumina is preferably porous. The average pore diameter of the porous alumina is preferably 50 to 500 nm. The average pore volume per mass of the porous alumina is preferably about 0.3 to 3 ml / g.
[0098]
The alumina hydrate can be synthesized by a sol-gel method in which ammonia is added to an aluminum salt solution to precipitate or a method in which an alkali aluminate is hydrolyzed. Anhydrous alumina can be obtained by dehydrating alumina hydrate by heating.
The filler is preferably 5 to 2000% by mass based on the dry mass of the binder in the layer to be added.
[0099]
-Crosslinking agent-
The cross-linking agent can be blended in order to adjust the storage stability, thermoplasticity, etc. of the toner image-receiving layer. As such a crosslinking agent, a compound having two or more known reactive groups in the molecule as an epoxy group, isocyanate group, aldehyde group, active halogen group, active methylene group, acetylene group or the like is used as a reactive group.
[0100]
As the cross-linking agent, a compound having two or more groups capable of forming a bond by hydrogen bond, ionic bond, coordination bond or the like can be used.
As the crosslinking agent, known compounds can be used as coupling agents for resins, curing agents, polymerization agents, polymerization accelerators, coagulants, film-forming agents, film-forming aids, and the like. Examples of coupling agents include, for example, chlorosilanes, vinyl silanes, epoxy silanes, aminosilanes, alkoxyaluminum chelates, titanate coupling agents, etc., and "Handbook Rubber / Plastic Compounding Chemicals" (Rubber Digest Co., Ltd.) Ed) and the like can be used.
[0101]
-Charge control agent-
The toner image-receiving layer of the present invention preferably contains a charge adjusting agent in order to adjust toner transfer, adhesion, etc., and to prevent charge adhesion of the toner image-receiving layer.
Conventionally known various charge control agents can be used as the charge control agent. Examples of such a charge control agent include cationic surfactants, surfactants such as anionic surfactants, amphoteric surfactants, and nonionic surfactants, as well as polymer electrolytes and conductive metal oxides. Things can be used. For example, quaternary ammonium salts, polyamine derivatives, cation-modified polymethyl methacrylate, cationic antistatic agents such as cation-modified polystyrene, anionic antistatic agents such as alkyl phosphates and anionic polymers, fatty acid esters, polyethylene oxide, etc. Nonionic antistatic agents may be mentioned, but are not limited thereto.
[0102]
When the toner has a negative charge, for example, a cation or nonion is preferable as the charge adjusting agent to be blended in the toner image receiving layer.
Examples of the conductive metal oxide include ZnO and TiO.₂, SnO₂, Al₂O₃, In₂O₃, SiO₂, MgO, BaO, MoO₃Etc. These conductive metal oxides may be used alone or in combination with these composite oxides. Further, the metal oxide may further contain a different element, for example, Al, In, etc., TiO 2 with respect to ZnO.₂Nb, Ta, etc., SnO₂Can contain (doping) Sb, Nb, a halogen element, or the like.
[0103]
-Other additives-
The material that can be used in the toner image-receiving layer of the present invention can contain various additives for improving the stability of the output image and improving the stability of the toner image-receiving layer itself. Examples of the additive include various known antioxidants, antioxidants, deterioration inhibitors, ozone deterioration inhibitors, ultraviolet absorbers, metal complexes, light stabilizers, preservatives, fungicides, and the like.
[0104]
Examples of the antioxidant include a chroman compound, a coumaran compound, a phenol compound (eg, hindered phenol), a hydroquinone derivative, a hindered amine derivative, and a spiroindane compound. The antioxidant is described in JP-A No. 61-159644.
[0105]
Examples of the antiaging agent include those described in “Handbook Rubber / Plastic Compounding Chemicals Revised 2nd Edition” (1993, Rubber Digest Co.) p76-121.
[0106]
Examples of the ultraviolet absorber include benzotriazole compounds (described in U.S. Pat. No. 3,533,794), 4-thiazolidone compounds (described in U.S. Pat. No. 3,352,681), benzophenone compounds (described in JP-A-46-2784), and Examples thereof include ultraviolet absorbing polymers (described in JP-A-62-260152).
[0107]
Examples of the metal complex include U.S. Pat. Nos. 4,241,155, 4,425,018 and 4,254,195, JP-A-61-88256, JP-A-62-174741, JP-A-63-199248, JP-A-1-75568. Nos. 1 and 74272 are appropriate.
Further, ultraviolet absorbers and light stabilizers described in "Handbook Rubber / Plastic Compounding Chemicals Revised 2nd Edition" (1993, Rubber Digest Co., Ltd.) p122 to 137 are also preferably used.
[0108]
In addition, as described above, a known photographic additive can be added to the material that can be used for the toner image-receiving layer of the present invention, if necessary. As the photographic additive, for example, Research Disclosure Magazine (hereinafter abbreviated as RD) No. 17643 (December 1978), No. 18716 (November 1979) and 307105 (November 1989), and the corresponding parts are summarized below.

[0109]
The toner image-receiving layer of the present invention is provided by applying a coating solution containing a polymer used for the toner image-receiving layer on the support with a wire coater or the like and drying. The film forming temperature of the polymer used in the present invention is preferably room temperature or higher for storage before printing, and preferably 100 ° C. or lower for fixing toner particles.
[0110]
The toner image-receiving layer of the present invention has a coating weight after drying of, for example, 1 to 20 g / m.²Is preferably 4 to 15 g / m.²Is more preferable.
The thickness of the toner image receiving layer is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 1 to 30 μm, and more preferably 2 to 20 μm.
[0111]
[Physical properties of toner image-receiving layer]
The toner image-receiving layer has a 180 degree peel strength at a fixing temperature with the fixing member of preferably 0.1 N / 25 mm or less, and more preferably 0.041 N / 25 mm or less. The 180 degree peel strength can be measured according to the method described in JIS K6887 using the surface material of the fixing member.
The toner image receiving layer preferably has high whiteness. The whiteness is preferably 85% or more as measured by the method defined in JISP 8123. Further, in the wavelength range of 440 nm to 640 nm, the spectral reflectance is preferably 85% or more, and the difference between the maximum spectral reflectance and the minimum spectral reflectance in the same wavelength region is preferably within 5%. Furthermore, the spectral reflectance is preferably 85% or more in the wavelength region of 400 nm to 700 nm, and the difference between the maximum spectral reflectance and the minimum spectral reflectance in the same wavelength region is more preferably within 5%.
As the whiteness, specifically, CIE 1976 (L^*a^*b^*) In color space, L^*The value is preferably 80 or more, more preferably 85 or more, and still more preferably 90 or more. The white color is preferably as neutral as possible. The white color is L^*a^*b^*In space, (a^*)²+ (B^*)²The value of is preferably 50 or less, more preferably 18 or less, and still more preferably 5 or less.
[0112]
The toner image receiving layer preferably has high gloss. As the glossiness, the 45 ° glossiness is preferably 60 or more, more preferably 75 or more, and still more preferably 90 or more in the entire region from white without toner to black having the maximum density.
However, the glossiness is preferably 110 or less. If it exceeds 110, it becomes like metallic luster, which is not preferable as image quality.
In addition, the said glossiness can be measured based on JISZ8741.
[0113]
The toner image-receiving layer preferably has high smoothness. As the smoothness, the arithmetic average roughness (Ra) is preferably 3 μm or less, more preferably 1 μm or less, and even more preferably 0.5 μm or less in the entire region from white without toner to black having the maximum density.
The arithmetic average roughness can be measured based on JIS B 0601, B 0651, B 0652.
[0114]
The toner image-receiving layer preferably has one physical property among the following items, more preferably a plurality of items, and most preferably all physical properties.
(1) Tm (melting temperature) of the toner image-receiving layer is 30 ° C. or higher and Tm + 20 ° C. or lower of the toner.
(2) The toner image receiving layer has a viscosity of 1 × 10⁵The temperature at which CP becomes 40 ° C. or higher, which is lower than that of toner.
(3) The storage elastic modulus (G ′) at the fixing temperature of the toner image receiving layer is 1 × 10²~ 1x10⁵Pa, loss elastic modulus (G ″) is 1 × 10²~ 1x10⁵Pa.
(4) The loss tangent (G ″ / G ′), which is the ratio of the loss elastic modulus (G ″) at the fixing temperature of the toner image-receiving layer and the storage elastic modulus (G ′), is 0.01 to 10.
(5) The storage elastic modulus (G ′) at the fixing temperature of the toner image-receiving layer is −50 to +2500 with respect to the storage elastic modulus (G ″) at the fixing temperature of the toner.
(6) The inclination angle of the molten toner on the toner image-receiving layer is 50 degrees or less, particularly 40 degrees or less.
The toner image-receiving layer preferably satisfies the physical properties disclosed in Japanese Patent No. 2788358, Japanese Patent Application Laid-Open Nos. 7-248637, 8-305067, and 10-239889. .
[0115]
The physical property (1) can be measured by a differential scanning calorimeter (DSC). The physical properties (2) to (3) can be measured using, for example, a flow tester CFT-500 or 500D manufactured by Shimadzu Corporation. The physical properties (5) to (7) can be measured using a rotational rheometer (for example, a dynamic analyzer RADII manufactured by Rheometric). The physical property (8) can be measured by a method disclosed in JP-A-8-334916 using a contact angle measuring device manufactured by Kyowa Interface Science Co., Ltd.
[0116]
As the toner image-receiving layer, 1 × 10⁶~ 1x10¹⁵Ω / cm²It is preferable to have a surface electrical resistance in the range of (under conditions of 25 ° C. and 65% RH).
The surface resistance is 1 × 10⁶Ω / cm²If it is less than 1, the amount of toner when the toner is transferred to the toner image-receiving layer is not sufficient, and the density of the resulting toner image tends to be low. On the other hand, the surface electrical resistance is 1 × 10¹⁵Ω / cm²Exceeding this amount generates more charge than necessary during transfer, and the toner is not sufficiently transferred, resulting in a low image density, and electrostatic charge is easily deposited during handling of the electrophotographic image receiving sheet. Misfeeds, double feeds, discharge marks, toner transfer missing, etc. may occur during copying.
Here, the measurement of the surface electrical resistance is based on JIS K 6911, the sample is conditioned for 8 hours or more in an environment of a temperature of 20 ° C. and a humidity of 65%, and R8340 manufactured by Advantest Corporation is used in the same environment. It is obtained by measuring after using for 1 minute after energization under the condition of an applied voltage of 100V.
[0117]
[Back layer]
In the electrophotographic image-receiving sheet of the present invention, the back layer is provided on the opposite side of the toner image-receiving layer with respect to the support for the purpose of imparting backside output suitability, improving backside output image quality, improving curl balance, and improving device passability. Is preferably provided.
Although there is no restriction | limiting in particular as a color of the said back layer, When the image receiving sheet for electrophotography of this invention is a double-sided output type image receiving sheet which forms an image also in a back surface, it is preferable that a back layer is also white. The whiteness and the spectral reflectance are preferably 85% or more like the surface.
Further, the back layer may have the same structure as that of the toner image receiving layer for improving the duplex output suitability. Various additives described above can be used for the back layer. As such an additive, it is particularly suitable to blend a matting agent, a charge adjusting agent and the like. The back layer may have a single layer configuration or a stacked configuration of two or more layers.
Further, in order to prevent offset at the time of fixing, when a releasable oil is used for the fixing roller or the like, the back layer may be oil absorbing.
The thickness of the back layer is usually preferably from 0.1 to 10 μm.
[0118]
[Other layers]
Examples of other layers in the electrophotographic image-receiving sheet include, for example, a surface protective layer, an adhesion improving layer, an intermediate layer, an undercoat layer, a cushion layer, a charge control (prevention) layer, a reflective layer, a tint adjusting layer, and a storage stability improvement. A layer, an adhesion preventing layer, an anti-curl layer, and a smoothing layer. These layers may be composed of a single layer or may be composed of two or more layers.
[0119]
-Surface protective layer-
The surface protective layer is for the purpose of protecting the surface of the electrophotographic image-receiving sheet of the present invention, improving storage stability, improving handleability, imparting writability, improving instrument passability, imparting anti-offset properties, etc. It can be provided on the surface of the toner image-receiving layer. The surface protective layer may be a single layer or may be composed of two or more layers. In the surface protective layer, various thermoplastic resins, thermosetting resins, and the like can be used as a binder, and it is preferable to use the same type of resin as the toner image receiving layer. However, thermodynamic characteristics, electrostatic characteristics, and the like do not need to be the same as those of the toner image-receiving layer, and can be optimized.
[0120]
The surface protective layer may contain the various additives described above that can be used for the toner image-receiving layer. In particular, the surface protective layer may be blended with other additives such as a matting agent in addition to the release agent used in the present invention. In addition, as said mat agent, various well-known things are mentioned.
The outermost surface layer in the electrophotographic image-receiving sheet of the present invention (for example, the surface protective layer when a surface protective layer is formed) has good compatibility with the toner in terms of fixing properties. preferable. Specifically, the contact angle with the melted toner is preferably, for example, 0 to 40 degrees.
[0121]
-Adhesion improvement layer, etc.-
The adhesion improving layer is preferably formed for the purpose of improving the adhesion between the support and the toner image receiving layer in the electrophotographic image receiving sheet of the present invention. The above-mentioned various additives can be blended in the adhesion improving layer, and it is particularly preferable to blend a crosslinking agent. The electrophotographic image-receiving sheet of the present invention preferably further comprises a cushion layer or the like between the adhesion improving layer and the toner image-receiving layer in order to improve toner acceptability.
[0122]
-Intermediate layer-
The intermediate layer is formed, for example, between the support and the adhesion improving layer, between the adhesion improving layer and the cushion layer, between the cushion layer and the toner image receiving layer, and between the toner image receiving layer and the storage stability improving layer. Can do. Of course, in the case of an electrophotographic image-receiving sheet comprising a support, a toner image-receiving layer, and an intermediate layer, the intermediate layer can be present, for example, between the support and the toner image-receiving layer.
[0123]
The thickness of the electrophotographic image-receiving sheet of the present invention is not particularly limited and may be appropriately selected depending on the intended purpose. For example, 50 to 350 μm is preferable, and 100 to 280 μm is more preferable.
[0124]
(toner)
The electrophotographic image-receiving sheet of the present invention is used with a toner image-receiving layer receiving toner during printing or copying.
The toner contains at least a binder resin and a colorant, and if necessary, a release agent and other components.
[0125]
-Toner binder resin-
Examples of the binder resin include styrenes such as styrene and parachlorostyrene; vinyl esters such as vinyl naphthalene, vinyl chloride, vinyl bromide, vinyl fluoride, vinyl acetate, vinyl propionate, vinyl benzoate, and vinyl butyrate; Methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, dodecyl acrylate, n-octyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, methyl α-chloroacrylate, methyl methacrylate, methacryl Methylene aliphatic carboxylic acid esters such as ethyl acetate and butyl methacrylate; Vinyl nitriles such as acrylonitrile, methacrylonitrile, and acrylamide; Vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, and vinyl isobutyl ether Tells; N-vinyl compounds such as N-vinyl pyrrole, N-vinyl carbazole, N-vinyl indole, N-vinyl pyrrolidone; single weight of vinyl monomers such as vinyl carboxylic acids such as methacrylic acid, acrylic acid and cinnamic acid Copolymers, copolymers thereof, and various polyesters can be used, and various waxes can be used in combination.
Among these resins, it is preferable to use resins of the same system as those used for the toner image receiving layer of the present invention.
[0126]
-Toner Colorant-
As the colorant, those usually used in toners can be used without limitation. For example, carbon black, chrome yellow, hansa yellow, benzidine yellow, sren yellow, quinoline yellow, permanent orange GTR, pyrazolone. Orange, Vulcan Orange, Watch Young Red, Permanent Red, Brilliantamine 3B, Brilliantamine 6B, Daypon Oil Red, Pyrazolone Red, Risor Red, Rhodamine B Lake, Lake Red C, Rose Bengal, Aniline Blue, Ultramarine Blue, Calco Examples include various pigments such as oil blue, methylene blue chloride, phthalocyanine blue, phthalocyanine green, and malachite green oxalelate. Acridine, xanthene, azo, benzoquinone, azine, anthraquinone, thioindico, dioxazine, thiazine, azomethine, indico, thioindico, phthalocyanine, aniline black, polymethine, triphenyl Examples include various dyes such as methane, diphenylmethane, thiazine, thiazole, and xanthene. These colorants may be used alone or in combination of two or more.
The content of the colorant is preferably in the range of 2 to 8% by mass. If the content of the colorant is 2% by mass or more, the coloring power is not weakened. On the other hand, if it is 8% by mass or less, the transparency is not impaired, which is preferable.
[0127]
-Toner release agent-
As the mold release agent, all known waxes can be used in principle, but polar waxes containing nitrogen such as relatively low molecular weight high crystalline polyethylene wax, Fischer-Tropsch wax, amide wax, urethane compound, etc. Etc. are particularly effective. The molecular weight of the polyethylene wax is preferably 1000 or less, and more preferably 300 to 1000.
[0128]
The compound having a urethane bond is suitable because even if it has a low molecular weight, the solid state can be maintained and the melting point can be set high for the molecular weight due to the strength of cohesive force due to the polar group. The preferred range of molecular weight is 300-1000. The raw materials are a combination of diisocyanate compounds and monoalcohols, a combination of monoisocyanic acid and monoalcohol, a combination of dialcohols and monoisocyanic acid, a combination of trialcohols and monoisocyanic acid, triisocyanic acid Various combinations such as combinations of compounds and monoalcohols can be selected, but in order not to increase the molecular weight, it is preferable to combine a compound of a polyfunctional group and a monofunctional group, and an equivalent functional group amount. It is important to ensure that
[0129]
Specific examples of the monoisocyanate compound among the raw material compounds include dodecyl isocyanate, phenyl isocyanate and derivatives thereof, naphthyl isocyanate, hexyl isocyanate, benzyl isocyanate, butyl isocyanate, and allyl isocyanate. It is done.
Examples of the diisocyanate compound include tolylene diisocyanate, 4,4′diphenylmethane diisocyanate, toluene diisocyanate, 1,3-phenylene diisocyanate, hexamethylene diisocyanate, 4-methyl-m-phenylene diisocyanate, and isophorone diisocyanate. Can be mentioned.
As the monoalcohol, it is possible to use very common alcohols such as methanol, ethanol, propanol, butanol, pentanol, hexanol, and heptanol.
Among the raw material compounds, as the dialcohols, a number of glycols such as ethylene glycol, diethylene glycol, triethylene glycol, trimethylene glycol; as the trialcohols, trimethylolpropane, triethylolpropane, trimethanolethane, etc. can be used. However, it is not necessarily limited to this range.
[0130]
These urethane compounds can be mixed with a resin and a colorant at the time of kneading and used as a kneaded and pulverized toner as in a normal release agent. Also, when used in the emulsion polymerization aggregation melting toner described above, it is dispersed in water together with a polymer electrolyte such as an ionic surfactant, a polymer acid or a polymer base, and heated to a melting point or higher to produce a homogenizer or pressure discharge. A fine dispersion is obtained by applying strong shearing with a mold disperser to prepare a release agent particle dispersion of 1 μm or less, which can be used together with a resin particle dispersion, a colorant dispersion and the like.
[0131]
-Toner and other components-
Further, the toner of the present invention may contain other components such as an internal additive, a charge control agent, and inorganic fine particles. As the internal additive, a magnetic material such as a metal such as ferrite, magnetite, reduced iron, cobalt, nickel, manganese, an alloy, or a compound containing these metals can be used.
[0132]
As the charge control agent, various commonly used charge control agents such as quaternary ammonium salt compounds, nigrosine compounds, dyes composed of complexes of aluminum, iron, chromium, and triphenylmethane pigments may be used. it can. A material that is difficult to dissolve in water is preferable from the viewpoint of controlling the ionic strength that affects the stability during aggregation and melting and reducing wastewater contamination.
[0133]
Examples of the inorganic fine particles include silica, alumina, titania, calcium carbonate, magnesium carbonate, tricalcium phosphate, and the like. Usually, all external additives on the toner surface are used. It is preferable to use by dispersing with a molecular base.
[0134]
Furthermore, a surfactant can be used for emulsion polymerization, seed polymerization, pigment dispersion, resin particle dispersion, release agent dispersion, aggregation, and stabilization thereof. For example, anionic surfactants such as sulfate ester, sulfonate, phosphate, and soap, cationic surfactants such as amine salt type and quaternary ammonium salt type, polyethylene glycol type, alkylphenol It is also effective to use a nonionic surfactant such as an ethylene oxide adduct system or a polyhydric alcohol system in combination. As a dispersing means at that time, a general means such as a rotary shear type homogenizer, a ball mill having a media, a sand mill, a dyno mill or the like can be used.
[0135]
An external additive may be further added to the toner as necessary. Examples of the external additive include inorganic powder and organic particles. Examples of the inorganic particles include SiO.₂TiO₂, Al₂O₃, CuO, ZnO, SnO₂, Fe₂O₃, MgO, BaO, CaO, K₂O, Na₂O, ZrO₂, CaO / SiO₂, K₂O. (TiO₂)_n, Al₂O₃・ 2SiO₂, CaCO₃, MgCO₃, BaSO₄, MgSO₄Etc. can be illustrated. Moreover, as said organic particle, resin powder, such as fatty acid or its derivative (s), powders, such as these metal salts, a fluorine resin, a polyethylene resin, an acrylic resin, can be used. For example, the average particle size of these powders is preferably 0.01 to 5 μm, and more preferably 0.1 to 2 μm.
[0136]
The method for producing the toner is not particularly limited, and (i) a step of forming aggregated particles in a dispersion obtained by dispersing resin particles to prepare an aggregated particle dispersion, (ii) in the aggregated particle dispersion. A step of adding and mixing a fine particle dispersion in which fine particles are dispersed to adhere the fine particles to the aggregated particles to form adhered particles; and (iii) heating and fusing the adhered particles to form toner particles. It is preferable that the toner is manufactured by a toner manufacturing method including the steps.
[0137]
-Toner physical properties-
The volume average particle diameter of the toner of the present invention is preferably from 0.5 μm to 10 μm.
If the volume average particle size of the toner is too small, there may be an adverse effect on toner handling (replenishability, cleaning properties, fluidity, etc.), and particle productivity may be reduced. On the other hand, if the volume average particle diameter of the toner is too large, the image quality and resolution due to graininess and transferability may be adversely affected.
Further, the toner of the present invention preferably satisfies the volume average particle size range of the toner and has a volume average particle size distribution index (GSDv) of 1.3 or less.
The ratio (GSDv / GSDn) of the volume average particle size distribution index (GSDv) to the number average particle size distribution index (GSDn) is preferably 0.95 or more.
In addition, the toner of the present invention satisfies the volume average particle diameter range of the toner, and the average value of the shape factor represented by the following formula is preferably 1.00 to 1.50.
Shape factor = (π × L²) / (4 × S)
(However, L represents the maximum length of toner particles, and S represents the projected area of toner particles.)
When the toner satisfies the above conditions, it is effective for image quality, particularly graininess, and resolution, and it is difficult for transfer and omission to occur, and handling properties are not adversely affected even if the average particle size is not small. Become.
[0138]
The storage elastic modulus G ′ (measured at an angular frequency of 10 rad / sec) at 150 ° C. of the toner itself is suitably 10 to 200 Pa from the viewpoint of improving the image quality and preventing the offset property in the fixing process.
[0139]
(Image forming method)
In the image forming method of the present invention, it is preferable to use a cooling / peeling type belt fixing type smoothing processing machine having a heating / pressurizing unit, a cooling unit, and a cooling / peeling unit as the heat / pressure treatment.
It is preferable that the heating and pressurizing unit is heated and pressurized to a temperature equal to or higher than the softening point of the thermoplastic resin in the image forming layer, cooled, and then peeled off from the belt member in the heating and pressing unit (cooling peeling process).
The heating and pressing means of the cooling-peeling belt type smoothing processor is not particularly limited, and examples thereof include a combination of a heating roller, a pressing roller, and an endless belt. Although it does not restrict | limit especially as said cooling means, For example, a cooling device, a heat sink, etc. which can ventilate cool air and can adjust cooling temperature etc. are used.
[0140]
It is preferable to apply pressure when the image forming material is brought into contact with the heating and pressurizing unit of the cooling and peeling type belt type smoothing processor. Although there is no restriction | limiting in particular as this pressurization method, It is preferable to apply nip pressure. The nip pressure is 1 to 100 kg / cm from the viewpoint of forming an image having excellent water resistance and surface smoothness and good gloss.²Is preferred, 5-30 kg / cm²Is more preferable. Further, the heating in the heating and pressurizing means is a temperature equal to or higher than the softening point of the thermoplastic resin in the image forming layer, and varies depending on the thermoplastic resin used, but is usually preferably 80 ° C. or higher and 200 ° C. or lower. The cooling temperature in the cooling means is preferably 80 ° C. or lower, more preferably 20 to 80 ° C., at which the thermoplastic resin layer in the image forming layer is sufficiently solidified.
[0141]
The surface of the fixing belt is preferably formed with a thin film made of at least one selected from the group consisting of silicone rubber, fluororubber, silicone resin, and fluororesin. Among them, an aspect in which a fluorocarbonsiloxane rubber layer having a uniform thickness is provided on the surface of the belt member, a silicone rubber layer having a uniform thickness is provided on the surface of the belt member, and the surface of the silicone rubber layer is provided. An embodiment in which a fluorocarbon siloxane rubber layer having a uniform thickness is provided.
[0142]
The fluorocarbon siloxane rubber preferably has a perfluoroalkyl ether group and / or a perfluoroalkyl group in the main chain.
Such a fluorocarbon siloxane rubber includes (A) a fluorocarbon siloxane having the following general formula (1) as a main component and an aliphatic unsaturated group, and (B) two or more ≡SiH groups in one molecule. Organopolysiloxane and / or fluorocarbon siloxane, wherein the content of the ≡SiH group is 1 to 4 times the molar amount of the aliphatic unsaturated group in the fluorocarbon siloxane rubber composition, (C) filling A cured product of a fluorocarbon siloxane rubber composition containing an agent and (D) an effective amount of a catalyst is preferably used.
[0143]
The (A) component fluorocarbon polymer is mainly composed of a fluorocarbon siloxane having a repeating unit represented by the following general formula (1) and has an aliphatic unsaturated group.
[0144]
[Chemical 1]

[0145]
Here, in the above formula (1), R¹⁰Is an unsubstituted or substituted monovalent hydrocarbon group having preferably 1 to 8 carbon atoms, preferably an alkyl group having 1 to 8 carbon atoms or an alkenyl group having 2 to 3 carbon atoms, particularly a methyl group. Is preferred. a and e are each 0 or 1, b and d are each an integer of 1 to 4, and c is an integer of 0 to 8. Moreover, x is an integer greater than or equal to 1, Preferably it is 10-30.
[0146]
Examples of the component (A) include those represented by the following formula (2).
[0147]
[Chemical 2]

[0148]
In the component (B), examples of the organopolysiloxane having an ≡SiH group include organohydrogenpolysiloxanes having at least two hydrogen atoms bonded to silicon atoms in the molecule.
[0149]
In the fluorocarbon siloxane rubber composition used in the present invention, when the fluorocarbon polymer as the component (A) has an aliphatic unsaturated group, the above-described organohydrogenpolysiloxane can be used as a curing agent. . That is, in this case, a cured product is formed by an addition reaction that occurs between an aliphatic unsaturated group in the fluorocarbon siloxane and a hydrogen atom bonded to a silicon atom in the organohydrogenpolysiloxane.
[0150]
As such organohydrogenpolysiloxane, various organohydrogenpolysiloxanes used in addition-curable silicone rubber compositions can be used.
[0151]
The above-mentioned organohydrogenpolysiloxane generally has at least one ≡SiH group, particularly 1 to 5 with respect to one aliphatic unsaturated hydrocarbon group in the fluorocarbon siloxane of component (A). It is suitable to mix | blend in such a ratio.
[0152]
Further, the fluorocarbon having an ≡SiH group may be a unit of the above formula (1) or R in the formula (1).¹⁰Is preferably a dialkylhydrogensiloxy group and the terminal is a ≡SiH group such as a dialkylhydrogensiloxy group or a silyl group, and examples thereof include those represented by the following formula (3).
[0153]
[Chemical 3]

[0154]
As the filler of the component (C), various fillers used in general silicone rubber compositions can be used. For example, fumed silica, precipitated silica, carbon powder, titanium dioxide, aluminum oxide, quartz powder, reinforcing fillers such as talc, sericite and bentonite, fibrous fillers such as asbestos, glass fiber, organic fiber, etc. It can be illustrated.
[0155]
As the catalyst of the component (D), chloroplatinic acid, alcohol-modified chloroplatinic acid, complexes of chloroplatinic acid and olefin, platinum black or palladium, which are known as addition reaction catalysts, alumina, silica, carbon, etc. Examples are those supported on the above-mentioned carrier, complex of rhodium and olefin, group VIII element of periodic table such as chlorotris (triphenylphosphine) rhodium (Wilkinson catalyst), rhodium (III) acetylacetonate, etc. However, these complexes are preferably used by being dissolved in a solvent such as an alcohol, ether, or hydrocarbon.
[0156]
In the fluorocarbon siloxane rubber composition used in the present invention, various compounding agents can be added as long as the object of the present invention to improve chemical resistance is not impaired. For example, diphenylsilane diol, low-polymerization degree molecular chain terminal hydroxyl-blocked dimethylpolysiloxane, dispersant such as hexamethyldisilazane, heat resistance improver such as ferrous oxide, ferric oxide, cerium oxide, iron octylate Further, colorants such as pigments can be blended as necessary.
[0157]
The belt member of the present invention is obtained by coating the surface of a heat-resistant resin or metal belt body with the fluorocarbon siloxane rubber composition, followed by heat curing. It can be diluted with a solvent such as fluoride or benzotrifluoride to obtain a coating solution, which can be applied by a general coating method such as spray coating, dip coating or knife coating. The temperature and time for heat curing can be selected as appropriate, and are selected according to the type of belt body and the manufacturing method, etc., in the range of normal temperature of 100 to 500 ° C. and time of 5 seconds to 5 hours.
[0158]
The thickness of the fluorocarbonsiloxane rubber layer formed on the surface of the belt member is not particularly limited, but is usually preferably 20 to 500 μm, more preferably 40 to 200 μm.
[0159]
As the surface roughness [arithmetic mean roughness (Ra)] of the belt member, 20 μm or less is preferable, and 5 μm or less is more preferable, particularly in that it is excellent in surface smoothness and can form an image having good gloss. 1 μm or less is more preferable. The arithmetic average roughness can be measured based on JIS B 0601, B 0651, B 0652.
The
[0160]
The method for forming an image on the electrophotographic image-receiving sheet of the present invention is not particularly limited as long as it is an electrophotographic method using a fixing belt, and any ordinary electrophotographic method can be applied.
For example, a color image can be preferably formed on the electrophotographic image-receiving sheet of the present invention. The color image can be formed using an electrophotographic apparatus capable of forming a full color image. A typical electrophotographic apparatus has an image receiving sheet conveying section, a latent image forming section, and a developing section arranged close to the latent image forming section. Depending on the model, a latent image is formed at the center of the apparatus main body. A toner image intermediate transfer portion in proximity to the image receiving portion and the image receiving sheet conveying portion.
[0161]
Furthermore, as a method for improving the image quality, an adhesive transfer or heat-assisted transfer system is known instead of or in combination with electrostatic transfer or bias roller transfer. For example, Japanese Patent Laid-Open Nos. 63-113576 and 5-341666 describe specific structures thereof. In particular, a method using a heat-assisted transfer type intermediate transfer belt is preferable when a toner having a small particle diameter is used.
[0162]
According to the image forming method of the present invention, even when an oilless machine without fixing oil is used, the electrophotographic image receiving sheet and the toner can be prevented from being peeled off, or the electrophotographic image receiving sheet and the toner component can be prevented from being offset. In addition, it is possible to realize a good image that has an unprecedented gloss and is rich in photographic feeling.
[0163]
FIG. 1 shows an electrophotographic apparatus of the present invention (for example, a full color laser printer (DCC-500) manufactured by Fuji Xerox), and the belt-like fixing unit of the electrophotographic apparatus is modified to the belt fixing type smoothing processor shown in FIG. It is used as. In FIG. 1, 100 is an image forming apparatus, 37 is a photosensitive drum, 9 is a developing device, 31 is an intermediate transfer belt, 16 is a recording sheet, and 25 is a belt-like fixing unit.
FIG. 2 shows a belt-type fixing unit 25 disposed in the electrophotographic apparatus (image forming apparatus) 100 of FIG.
As shown in FIG. 2, the belt-type fixing device 25 includes a heating roll 71, an endless belt 73 rotatably supported by a peeling roll 74 including the heating roll 71 and a tension roll 75, and the heating roll 71. And a pressure roll 72 in pressure contact with the endless belt 73.
A cooling heat sink 77 for forcibly cooling the endless belt 73 is disposed between the heating roll 71 and the peeling roll 74 on the inner surface side of the endless belt 73. 77 constitutes a cooling / sheet conveying section for cooling the electrophotographic image-receiving sheet and conveying the sheet.
[0164]
In the belt-type fixing device 25, as shown in FIG. 2, an electrophotographic transfer sheet having a color toner image transferred and fixed on the surface is heated to the heating roll 71 and the heating roll 71 via an endless belt 73. A color toner image is introduced into a pressure contact portion (nip portion) with the pressure roll 72 to be pressed so as to be positioned on the heating roll 71 side, and passes through the pressure contact portion between the heating roll 71 and the pressure roll 72. Further, the color toner image T is heated and melted and fixed on the electrophotographic transfer sheet.
[0165]
Thereafter, in the press-contact portion between the heating roll 71 and the pressure roll 72, for example, the toner is heated to a temperature of about 120 to 130 ° C. and melted to fix the color toner image to the image receiving layer. The photographic image-receiving sheet is conveyed together with the endless belt 73 while the image-receiving layer on the surface thereof is in close contact with the surface of the endless belt 73. In the meantime, the endless belt 73 is forcibly cooled by a cooling heat sink 77, and after the color toner image and the image receiving layer are cooled and solidified, the peeling roller 74 uses the waist (rigidity) of the electrophotographic image receiving sheet itself. It is peeled off.
[0166]
The surface of the endless belt 73 after the peeling process is completed is prepared for the next fixing process by removing residual toner and the like by a cleaner (not shown).
[0167]
The method for forming an image on the electrophotographic image-receiving sheet of the present invention is not limited to the above method as long as it is an electrophotographic method using a fixing belt. Any ordinary electrophotographic method can be applied.
For example, a color image can be preferably formed on the electrophotographic image-receiving sheet of the present invention. The color image can be formed using an electrophotographic apparatus capable of forming a full color image. A typical electrophotographic apparatus has an image receiving sheet conveying section, a latent image forming section, and a developing section arranged close to the latent image forming section. Depending on the model, a latent image is formed at the center of the apparatus main body. A toner image intermediate transfer portion in proximity to the image receiving portion and the image receiving sheet conveying portion.
[0168]
Furthermore, as a method for improving the image quality, an adhesive transfer or heat-assisted transfer system is known instead of or in combination with electrostatic transfer or bias roller transfer. For example, Japanese Patent Laid-Open Nos. 63-113576 and 5-341666 describe specific structures thereof. In particular, a method using a heat-assisted transfer type intermediate transfer belt is preferable when a toner having a small particle diameter is used.
[0169]
According to the image forming method of the present invention, even when an oilless machine without fixing oil is used, the electrophotographic image receiving sheet and the toner can be prevented from being peeled off, or the electrophotographic image receiving sheet and the toner component can be prevented from being offset. In addition, it is possible to realize a good image that has an unprecedented gloss and is rich in photographic feeling.
[0170]
【Example】
Examples of the present invention will be described below, but the present invention is not limited to these examples.
In the following examples and comparative examples, “%” and “parts” are based on mass.
[0171]
(Examples 1-6 and Comparative Examples 1-4)
-Production of support-
Hardwood bleached kraft pulp (LBKP; whiteness 90%) was beaten with a disc refiner to 300 ml (Canadian standard freeness, CFS) and adjusted to a fiber length of 0.60 mm. Additives were added to the pulp stock at the following ratio based on the mass of the pulp.

Note) The AKD means an alkyl ketene dimer (the alkyl part is derived from a fatty acid mainly composed of behenic acid). The EFA means an epoxidized fatty acid amide (the fatty acid part is derived from a fatty acid mainly composed of behenic acid).
[0172]
The obtained pulp paper stock was dried at a basis weight of 160 g / m using a long paper machine.²A base paper was prepared. In addition, PVA 1.2 g / m in solid content by a size press machine in the middle of the drying zone of the long paper machine², CaCO₃  0.9g / m²Attached.
Thereafter, using a machine calendar, the paper was passed so that a metal roll having a surface temperature of 110 ° C. was in contact with the surface (surface) of the base paper on which the toner image receiving layer was provided, and a calendar process was performed. The opposite surface (back surface) of the base paper was in contact with a metal roll having a surface temperature of 40 ° C.
Furthermore, using a soft calender, paper was fed so that a metal roll with a surface temperature of 210 ° C. was in contact with the surface of the base paper and a resin roll with a surface temperature of 40 ° C. was in contact with the back surface, and calendering was performed, and the density was 1.03 g / cm³A base paper was prepared.
[0173]
The following four types of pellets (1) to (4) are mixed, and the optical brightener, ultramarine, and TiO shown in Table 1 are mixed.₂A resin composition having a content of was prepared.
(1) PE: 100% by mass
(2) Benzooxolyl stilbene compound: 2% by mass + PE: 98% by mass
(3) Ultramarine blue (blue ultramarine blue / purple ultramarine blue = 1/2 (mass ratio)): 6% by mass + PE: 94% by mass
(4) TiO₂: 50% by mass + PE: 50% by mass
In addition, all PE in said (1)-(4) is HDPE / LDPE = 1/1 (mass ratio).
[0174]
Each of the obtained resin compositions was applied to the surface (surface) on the side where the toner image-receiving layer is provided to form a polyethylene resin layer having a dry film thickness of 25 μm.
On the other hand, a resin composition comprising HDPE / LDPE = 1/1 (mass ratio) was applied to the surface (back surface) on which the toner image-receiving layer is not provided to form a polyethylene resin layer having a dry film thickness of 20 μm.
Subsequently, the surface side was subjected to corona discharge treatment, and gelatin was 0.1 g / m 2.²Applied. Further, the back surface is subjected to corona discharge treatment, and gelatin is 0.06 g / m.², 0.02 g / m of colloidal silica²It apply | coated and the support body of Examples 1-6 and Comparative Examples 1-4 was produced.
[0175]
[Table 1]

* 1: Stilbene fluorescent whitening agent
* 2: Ultramarine blue (blue ultramarine blue / purple ultramarine blue = 1/2 (mass ratio))
* 3: Benzooxolyl stilbene fluorescent whitening agent
[0176]
-Production of electrophotographic image-receiving sheet-
Using the obtained supports of Examples 1 to 6 and Comparative Examples 1 to 4, electrophotographic image-receiving sheets were produced as follows.
[0177]
<Preparation of coating solution for toner image-receiving layer>
(Titanium dioxide dispersion)
The following components were mixed and dispersed using NBK-2 manufactured by Nippon Seiki Seisakusho to prepare a titanium dioxide dispersion (titanium dioxide pigment 40% by mass).
titanium dioxide
(Taipek (registered trademark) A-220, manufactured by Ishihara Sangyo) 40.0 g
PVA102 2.0g
Ion exchange water 58.0g
[0178]
(Toner image-receiving layer coating solution)
The following components were mixed and stirred to prepare a toner image-receiving layer coating solution.
15.5 g of the above titanium dioxide dispersion
Carnauba wax dispersion
(Cerosol 524, manufactured by Chukyo Yushi Co., Ltd.) 15.0 g
Polyester resin water dispersion
(Solid content 30%, KZA-7049, manufactured by Unitika) 100.0 g
Thickener (Alcox E30, Meisei Chemical) 2.0g
Anionic surfactant (AOT) 0.5g
Ion exchange water 80ml
The resulting toner image-receiving layer coating solution had a viscosity of 40 mPa · s, a surface tension of 34 mN / m, and a polyester resin Tg of 61 ° C.
[0179]
<Preparation of coating solution for back layer>
The following components were mixed and stirred to prepare a back layer coating solution.
Acrylic resin water dispersion
(Solid content 30%, high loss XBH-997L, manufactured by Seiko Chemical) 100.0 g
Matting agent
(Tecpomer MBX-12, manufactured by Sekisui Plastics Co., Ltd.) 5.0 g
Release agent (Hydrin D337, manufactured by Chukyo Yushi Co., Ltd.) 10.0 g
Thickener (CMC) 2.0g
Anionic surfactant (AOT) 0.5g
Ion exchange water 80ml
The back layer coating solution has a viscosity of 35 mPa · s and a surface tension of 33 mN.
/ M.
[0180]
<Coating of Back Layer and Toner Image Receiving Layer>
The back layer coating solution was applied to the back surface of each of the obtained Examples 1 to 6 and Comparative Examples 1 to 4 with a bar coater. Next, the toner image-receiving layer coating liquid was applied to the surface of the support with a bar coater, as in the case of the back layer.
The coating amount is 9 g / m in dry mass for the back layer.²The toner image-receiving layer was coated with the toner image-receiving layer coating solution and the back layer coating solution so that the dry mass was 12 g. The content of the thermoplastic resin in the toner image receiving layer was 64% by mass of the total mass of the toner image receiving layer.
The back layer and the toner image-receiving layer were dried online with hot air after coating. For drying, the amount of drying air and the temperature were adjusted so that both the back surface and the toner image-receiving surface were dried within 2 minutes after coating. The drying point was the point at which the coating surface temperature was the same as the wet bulb temperature of the drying air.
After drying, a soft calendar process was performed. The soft calendering process was performed using a soft calender, passing the paper so that a metal roller having a surface temperature of 55 ° C. was in contact with the surface of the toner image-receiving layer, and a nip pressure of 235 kN / m.
[0181]
<Evaluation>
The obtained electrophotographic image-receiving sheet was cut into A4, and a portrait image of a woman was used as a print image. The printer used was an image forming apparatus in which the fixing unit of the Fuji Xerox full color laser printer (DCC-500) shown in FIG. 1 was modified to the belt-like fixing unit shown in FIG. 2 (belt and cooling conditions are as follows) ) Was used.
−Belt−
Belt support: polyimide (PI) film, width = 50 cm,
Thickness = 80μm
Release layer material for belt: SIFEL 610, which is a fluorocarbon siloxane rubber precursor, was vulcanized and cured to a film thickness of 50 μm.
-Cooling conditions-
Cooler: Heat sink length = 80mm
Speed: 53mm / sec
[0182]
<Evaluation of sensory image quality>
About the obtained real image sample, the image quality, color tone, and brightness as silver salt photograph-like suitability were evaluated by the following criteria by a person who is relatively good at evaluating the image quality of photographs. The results are shown in Table 2.
[Evaluation criteria]
A: The image quality is equivalent to a silver halide photograph.
B: Image quality close to that of a silver salt photograph and acceptable as a photograph.
C: Although the image quality is different from that of a silver halide photograph, it is acceptable to some extent as a photograph.
D: The image quality is clearly inferior from the silver salt photograph and is not acceptable as a photograph.
E: Image quality is not acceptable at all.
[0183]
[Table 2]

[0184]
【The invention's effect】
According to the present invention, a support for an electrophotographic image-receiving sheet can be obtained in which a polyolefin resin layer is provided on both surfaces of a base paper, and the contents of the fluorescent whitening agent and the bluing agent in the polyolefin resin layer are optimized. .
In addition, according to the present invention, a high-quality electronic device having good silver salt photographic-like suitability (image quality, color tone, brightness, texture, etc.) using the support for an electrophotographic image-receiving sheet, and close to the silver salt photographic image quality. An electrophotographic image-receiving sheet from which a photographic print can be obtained can be provided.
[Brief description of the drawings]
FIG. 1 is a schematic view showing an example of an electrophotographic apparatus of the present invention.
FIG. 2 is a schematic view showing an example of a cooling and peeling type belt fixing type smoothing processing machine used in the fixing unit of FIG. 1;
[Explanation of symbols]
25 Belt type fixing device
71 Heating roll
72 Pressure roll
74 Peeling roll
75 Tension roll
73 Endless belt
77 Cooling heat sink
100 Image forming apparatus

Claims (15)

In a support for an electrophotographic image-receiving sheet in which a polyolefin resin layer is provided on both sides of a base paper, at least the polyolefin resin layer on the side (surface side) on which the toner image-receiving layer is provided is 0.01 to An electrophotographic image-receiving sheet support comprising 0.5% by mass and a bluing agent of 0.01 to 1.3% by mass. 2. The electrophotographic image-receiving sheet according to claim 1, wherein the optical brightener is at least one selected from stilbene compounds, benzoxazolyl stilbene compounds, coumarin compounds, pyrazole compounds, and oxazole compounds. Support. The support for an electrophotographic image-receiving sheet according to any one of claims 1 to 2, wherein the bluing agent is at least one selected from ultramarine, cobalt blue, cobalt oxide phosphate and quinacdrine pigments. The support for an electrophotographic image-receiving sheet according to claim 3, wherein the bluing agent is ultramarine blue, and the ultramarine blue is a mixture of blue and blue ultramarine blue. The support for an electrophotographic image-receiving sheet according to any one of claims 1 to 4, wherein at least the polyolefin resin layer on the side (surface side) on which the toner image-receiving layer is provided contains 3 to 30% by mass of a white pigment. The white pigment is at least one selected from titanium dioxide, calcium carbonate, barium sulfate, zinc white, kaolin, calcined kaolin, magnesium carbonate, aluminum silicate, calcium silicate, magnesium silicate, and synthetic amorphous silica. The support for an electrophotographic image-receiving sheet according to claim 5. The support for an electrophotographic image-receiving sheet according to any one of claims 1 to 6, wherein the base paper contains a pulp stock having a pulp whiteness specified by JIS P8123 of 88% or more. The support for an electrophotographic image-receiving sheet according to any one of claims 1 to 7, comprising a pulp stock having a base paper mass average fiber length of 0.45 to 0.70 mm. The support for an electrophotographic image-receiving sheet according to any one of claims 1 to 8, wherein the base paper contains at least one of an alkyl ketene dimer and an epoxidized fatty acid amide as a sizing agent. The support for an electrophotographic image-receiving sheet according to any one of claims 1 to 9, wherein the base paper contains 0.01 to 0.5% by mass of a fluorescent brightening agent. 11. A support, comprising at least one toner image-receiving layer on one surface of the support and at least one back layer on the other surface of the support. An electrophotographic image-receiving sheet, wherein the electrophotographic image-receiving sheet support according to any one of the above is used. 12. The toner of an electrophotographic image receiving sheet according to claim 11, wherein a cooling and peeling belt fixing type smoothing processor having a heating and pressing unit, a cooling unit, and a cooling and peeling unit is used, and the heating and pressing unit is used. An image forming method comprising: heating and pressurizing to a temperature equal to or higher than a softening point of a thermoplastic resin in an image receiving layer; cooling and then peeling from a belt member in the heating and pressurizing unit. The image forming method according to claim 12, wherein a layer made of a fluorocarbon siloxane rubber having a uniform thickness is provided on the surface of the fixing belt. 13. The image according to claim 12, wherein the surface of the fixing belt has a silicone rubber layer having a uniform thickness, and the silicone rubber layer has a layer made of a fluorocarbon siloxane rubber having a uniform thickness. Forming method. The image forming method according to claim 13, wherein the fluorocarbon siloxane rubber has a perfluoroalkyl ether group and / or a perfluoroalkyl group in a main chain.

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