JP3905009B2 - Electrophotographic image receiving sheet and image forming method - Google Patents

Description

【００９１】
〔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度剥離強さが、０．１Ｎ／２５ｍｍ以下、更に好ましくは、０．０４１Ｎ／２５ｍｍ以下であることが適当である。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が５％以内が好ましい。更には、４００ｎｍ〜７００ｎｍ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が５％以内がより好ましい。
また、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^＊値が８０以上であるのが好ましく、８５以上であるのが好ましく、９０以上であるのがより好ましい。また、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の値が５０以下であるのが好ましく、１８以下であるのがより好ましく、５以下であるのが更に好ましい。
【００９２】
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度光沢度が６０以上であるのが好ましく、７５以上であるのがより好ましく、９０以上であるのが更に好ましい。
但し、光沢度は１１０以下であることが好ましい。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。
【００９３】
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）が３μｍ以下であるのが好ましく、１μｍ以下であるのがより好ましく、０．５μｍ以下であるのが更に好ましい。
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。
【００９４】
前記トナー受像層は、以下の項目の内の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、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、１×１０²〜１×１０^５Ｐａ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。
【００９５】
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。
【００９６】
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、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。
【００９７】
尚、前記支持体に対し、トナー受像層と反対側の面の表面電気抵抗としては、５×１０^８〜３．２×１０^１０Ω／ｃｍ^２が好ましく、１×１０^９〜１×１０^１０Ω／ｃｍ^２がより好ましい。
本発明において、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。
【００９８】
前記トナー受像層の厚さは、使用されるトナーの粒子径の１／２以上、好ましくは、１倍〜３倍の厚さであることが適当である。また、トナー受像層としては、特開平５−２１６３２２号公報及び特開平７−３０１９３９号公報に開示された厚みのものが好ましい。具体的には、トナー受像層の厚みは、例えば、１〜５０μｍ、好ましくは、５〜１５μｍが適当である。
【００９９】
［その他の層］
前記その他の層としては、例えば、表面保護層、バック層、中間層、密着改良層、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。
【０１００】
−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。
【０１０１】
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。
【０１０２】
−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紙の場合、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。
【０１０３】
−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。
【０１０４】
−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。
【０１０５】
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。
【０１０６】
＜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。
【０１０７】
−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。
【０１０８】
−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。
【０１０９】
−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については分子量が１０００以下のものが特に有効であり、３００〜１０００の範囲がより好ましい。
【０１１０】
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。
【０１１１】
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。
【０１１２】
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。
【０１１３】
−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。
【０１１４】
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。
【０１１５】
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。
【０１１６】
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。
【０１１７】
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、好ましくは、０．１〜２μｍであることが適当である。
【０１１８】
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。
【０１１９】
−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）が１．３以下であることが好ましい。
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）は少なくとも０．９５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が１．００〜１．５０が好ましい。
形状係数＝〔π×（２×Ｌ）^２〕／（４×Ｓ）
（但し、Ｌはトナー粒子の最大半径、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。
【０１２０】
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。
【０１２１】
＜画像形成方法＞
本発明の電子写真用受像材料の上に前記トナーが転写され、このトナーが受像材料上のトナー受像層に定着されて画像が形成される。
本発明の画像形成方法は、第１の態様として、前記電子写真用受像シートに、トナー画像を形成した後、前記電子写真用受像シートの該画像形成面を、定着ベルト及び定着ローラにより、加熱及び加圧し、冷却した後、前記定着ベルトから剥離する。
また、本発明の画像形成方法は、第２の態様として、前記電子写真用受像シートに、トナー画像を形成した後、熱ローラにより定着した後、更に、前記電子写真用受像シートの該画像形成面を、定着ベルト及び定着ローラにより、加熱及び加圧し、冷却した後、前記定着ベルトから剥離する。
前記第１及び第２の態様の画像形成方法において、電子写真用受像シートを、定着ベルト及び定着ローラにより、８０℃以上１１０℃未満の温度に加熱加圧し、８０℃以下の温度で定着ベルトから剥離することにより、ポリオレフィン層が軟化し、圧力により変形するが、ブリスターは発生しない条件で加熱加圧すると共に、ポリオレフィン層が固化する条件まで冷却することにより、耐水性、表面平滑性に優れ、良好な光沢を有するトナー受像層表面を形成する点で好ましい。
【０１２２】
なお、転写の方法としては、通常の電子写真方法で使用される方法、例えば、現像ローラ上に形成したトナー画像を直接受像材料に転写する直接転写方式、或いは中間転写ベルト等に一次転写した後、受像材料に転写する中間転写ベルト方式がある。環境安定性及び高画質化の面から、中間転写ベルト方式が好ましくは使用される。
【０１２３】
本発明の電子写真用受像材料は、定着ベルトを有する電子写真装置を使用して、受像材料上に転写されたトナーが受像材料に定着される。ベルト定着方式としては、例えば、特開平１１−３５２８１９号公報に記載のオイルレスタイプのベルト定着方法、特開平１１−２３１６７１号公報及び特開平５−３４１６６６号公報に記載の二次転写と定着を同時に達成する方法等が知られている。本発明でいう定着ベルトを有する電子写真装置は、例えば、少なくとも、トナーを溶融し、加圧し得る加熱加圧部と、トナーの付着した受像材料をトナー受像層と接する状態で搬送することができる定着ベルトと、任意に、加熱した受像材料を定着ベルトに付着させたままの状態で冷却できる冷却部とを有するベルト方式のトナー定着部を有する電子写真装置が挙げられる。このような定着ベルトを有する電子写真装置にトナー受像層を有する電子写真用受像材料を使用することにより、トナー受像層に付着したトナーが、受像材料に広がることなく細密に定着されると共に、定着ベルトに密着した状態で溶融トナーが冷却・固化するので、トナー受像層にトナーが完全に埋め込まれた状態でトナー受像層に受容される。従って、画像段差がなく、光沢のある平滑なトナー画像を得ることができる。
【０１２４】
本発明で形成される電子写真用受像シートは、特にオイルレス方式のベルト定着方式による画像形成方法に好適であり、これにより、オフセットが大幅に改善される。但し、それ以外の各種の画像形成法に対しても、同様に使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を使用することにより、フルカラー画像を、画質の改善及びひび割れの防止を図りながら、好適に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、受像紙搬送部と、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紙搬送部に近接してトナー像中間転写部を有している。
【０１２５】
更に、画質の向上を図るための方法として、静電転写又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る方法が好ましい。また、電子写真用受像シートへのトナー転写後又は転写後半の中間ベルトには冷却装置を設けることが好ましい。該冷却装置により、トナー（トナー画像）は、それに使用されるバインダー樹脂の軟化温度又はトナーのガラス転移温度以下に冷却され、効率よく電子写真用受像シートに転写され、中間ベルトからの剥離が可能となる。
【０１２６】
定着は、最終画像の光沢や平滑性を左右する重要な工程である。定着方式は、加熱加圧ローラによる定着、ベルトを用いたベルト定着などが知られているが、上記光沢、平滑性等の画像品質の点からはベルト定着方式の方が好ましい。ベルト定着方式については、例えば、特開平１１−３５２８１９号公報に記載のオイルレスタイプのベルト定着方法、特開平１１−２３１６７１号公報及び特開平５−３４１６６６号公報に記載の二次転写と定着を同時に達成する方法等が知られている。また、定着ベルトと定着ローラによる加圧及び加熱の前に、熱ローラによる一次定着を行ってもよい。
【０１２７】
前記定着ベルトの表面は、トナーの剥離性又はトナー成分のオフセットを防止するためにシリコーン系又はフッ素系或いはその併用系の表面処理が施されていてもよい。また、定着の後半にはベルトの冷却装置を備え、電子写真用受像シートの剥離を良好にすることが好ましい。冷却温度は、トナーバインダー樹脂及び／又は電子写真用受像シートのトナー受像層のポリマーの軟化点以下、或いはガラス転移点以下にすることが好ましい。一方、定着初期には、電子写真用受像シートのトナー受像層又はトナーが十分に軟化する温度まで昇温する必要がある。具体的には冷却温度は８０℃以下、３０℃以上が実用上好ましく、定着初期においては１８０℃以下、１００℃以上が好ましい。
【０１２８】
ここで、前記画像形成装置に使用される定着ベルトとしては、例えば、ポリイミド、電鋳ニッケル及びアルミニウム等を基材として形成された無端状ベルトであることが適当である。
前記定着ベルトの表面には、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、定着ベルト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、前記定着ベルト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。
【０１２９】
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。
【０１３０】
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。
【０１３１】
【化１】

【０１３２】
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。
【０１３３】
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。
【０１３４】
【化２】

【０１３５】
（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。
【０１３６】
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。
【０１３７】
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。
【０１３８】
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。
【０１３９】
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。
【０１４０】
【化３】

【０１４１】
（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。
【０１４２】
（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。
【０１４３】
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、耐溶剤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。
【０１４４】
前記本発明の定着用ベルトは、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。
【０１４５】
前記定着ベルト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、トナーの剥離性或いはトナー成分のオフセットを防止して画像の良好な定着性を得るために２０〜５００μｍ、特に４０〜２００μｍが好ましい。
【０１４６】
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。
【０１４７】
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。
【０１４８】
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、受像シート及びトナーの剥離性、或いは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。
【０１４９】
【実施例】
以下、実施例により本発明を詳細に説明するが、本発明は、下記実施例に何ら限定されるものではない。
尚、以下の実施例において、「％」及び「部」は、質量基準である。
【０１５０】
（実施例１）
−基紙の調製−
広葉樹晒クラフトパルプ（ＬＢＫＰ）をディスクリファイナーで３００ｃｃ（カナダ標準ろ水度、Ｃ．Ｆ．Ｓ．）まで叩解し、繊維長０．５８ｍｍ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。
添加剤の種類 量（％）
カチオン澱粉 １．２
アルキルケテンダイマー（ＡＫＤ） ０．５
アニオンポリアクリルアミド ０．３
エポキシ化脂肪酸アミド（ＥＦＡ） ０．２
ポリアミドポリアミンエピクロルヒドリン ０．３
注）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）を意味し、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。
【０１５１】
得られたパルプ紙料を、長網抄紙機により坪量１５０ｇ／ｍ^２の原紙を作製した。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、ＰＶＡ １．０ｇ／ｍ^２、ＣａＣｌ_２ ０．８ｇ／ｍ^２を付着した。
抄紙工程の最後で、ソフトカレンダーを用いて、密度を１．０１ｇ／ｃｍ^３に調整した。得られた基紙において、トナー受像層が設けられる側において、金属ロールが接するように通紙し、金属ロールの表面温度は１４０℃であった。得られた基紙の白色度は９１％、王研式平滑度は２６５秒、ステキヒト・サイズ度は１２７秒であった。
【０１５２】
得られた基紙を、出力１７ｋＷのコロナ放電によって処理した後、裏面に表面マット粗さ１０μｍのクーリングロールを用い、表１に示した組成のポリエチレン樹脂を溶融吐出膜温度３２０℃、ラインスピード２５０ｍ／分で単層押出ラミネートし、厚さ２２μｍのポリエチレン樹脂層を設けた。
【０１５３】
【表１】

【０１５４】
次に、トナー受像層を塗設する側である基紙の表面に表面マット粗さ０．７μｍのクーリングロールを用い、ポリエチレン樹脂、表２に示したようにマスターバッチ化した酸化チタン、５質量％含有するＬＤＰＥマスターバッチ郡青とを、最終的に組成が表３に示した組成になるように混合したものを、溶融吐出膜温度３２０℃、ラインスピード２５０ｍ／分で単層押出ラミネートし、厚さ２９μｍのポリエチレン樹脂層を設けた。
その後、表面に出力１８ｋＷ、裏面に出力１２ｋＷのコロナ放電により処理した後、表面にはゼラチン下塗り層を、裏面にはコロイダルアルミナ、コロイダルシリカ、及びＰＶＡを含有する帯電防止下塗り層とを設け、支持体を作製した。
【０１５５】
【表２】

【０１５６】
【表３】

【０１５７】
次に、前記支持体のおもて面上に、自己分散型ポリエステル樹脂水分散物、カルナバワックス水分散物、二酸化チタンのＰＶＡ分散物と分子量約１０万のポリエチレンオキサイドを、最終的に表４に示した塗設量組成になるように、トナー受像層をバーコーターで設けて、実施例１の電子写真用受像シートを作製した。なお、塗布液の粘度は７０ｍＰａ・ｓ、表面張力３０ｍＮ／ｍ、ｐＨ７．８であった。
得られた実施例１の電子写真用受像シートの白色度は８７、不透明度は９３であった。
【０１５８】
【表４】

【０１５９】
（比較例１）
実施例１と同様にして、基紙、支持体、及び電子写真用受像シートを作製した。ただし、トナー受像層の組成は、表５に示したように変更した。
【０１６０】
【表５】

【０１６１】
（比較例２）
実施例１と同様にして、基紙、支持体、及び電子写真用受像シートを作製した。ただし、トナー受像層の組成は、表６に示したように変更した。
【０１６２】
【表６】

【０１６３】
次に、得られた実施例１及び比較例１，２の電子写真用受像シートを、Ａ６サイズに裁断し、富士ゼロックス（株）製、カラー電子写真プリンターＤｏｃｕＣｅｎｔｅｒＣｏｌｏｒ４００を用いて、白、灰、黒、黄、マゼンタ、シアン、青、緑、及び赤のカラー画像を印画した。但し、比較例２は、およそ５枚印画したうち４枚が定着部を通紙しなかった。
【０１６４】
印画した画像を、図１に示すベルト定着装置１を用い、後光沢化処理を行った。但し、ベルト２の搬送速度は６０ｍｍ／秒、加熱ローラ３及び加圧ローラ４の設定温度は１３０℃に設定した。図１中６は冷却装置である。
印画、後処理直後に白地の２０度光沢度を、ＪＩＳ Ｚ８７４１に基づいて測定した。その後、２８℃で８５％ＲＨ環境下、１週間、２週間放置した。各経時での光沢度を測定した結果を表７に示す。
また、耐ブロッキング性を、トナー受像面黒部と裏面とを重ね合わせて５０／ｃｍ^２の荷重をかけた状態で４０℃のオーブン中に４８時間放置し、その後はがすことにより、下記基準で評価した。結果を表７に示す。
＜評価基準＞
◎：接着は見られなかった。
○：接着は見られたが、容易に剥がすことができ、接着跡も見られなかった。
△：接着は見られたが、容易に剥がすことができた。但し、接着跡が見られる。
×：接着があり、剥がすと画面に欠落が生じた。
【０１６５】
【表７】

表７中、×印はひび割れが発生し、光沢度が測定不能であった。
なお、実施例１において、カルナバワックスをポリエチレンワックスに変更しても、同様の結果が得られた。
【０１６６】
（実施例２）
実施例１で作成した支持体のおもて面上に、自己分散型アクリル樹脂水分散物を用い、最終的に表８の塗設量組成になるようにして、下引き層をバーコーターで設けた。乾燥させた後、更に下引き層上に、自己分散型ポリエステル樹脂水分散物、カルナバワックス水分散物、二酸化チタンのＰＶＡ分散物と分子量約１０万のポリエチレンオキサイドとを、最終的に表９の塗設量組成になるようにして、トナー受像層をバーコーターで設けて、重層構成のトナー受像層を有する、実施例２の電子写真用受像シートを作成した。
【０１６７】
【表８】

【０１６８】
【表９】

【０１６９】
（実施例３〜５）
実施例２と同様にして、基紙、支持体、及び電子写真用受像シートを作成した。但し、トナー受像層、下引き層のカルナバワックス、ポリエチレンオキサイド量は表１０に示したように変更した。
【０１７０】
得られた実施例２〜５の電子写真用受像シートについて、図１に示したベルト定着装置１を用い、後光沢化処理を行った。その後、実施例１と同様の方法で白地の２０度光沢度及び耐ブロッキング性を評価した。結果を表１０に示す。
【０１７１】
【表１０】

なお、実施例２〜５において、カルナバワックスをポリエチレンワックスに変更しても、同様の結果が得られた。
【０１７２】
【発明の効果】
以上説明したように、本発明によれば、特に、オイルレス定着が可能であり、高湿環境下で放置しても白地部分の光沢度の低下が少なく、耐ブロッキング性及び脆性に優れた高画質な電子写真用受像シートが得られる。
【図面の簡単な説明】
【図１】図１は、実施例で用いたベルト定着装置の一例を示す概略図である。
【符号の説明】
１ ベルト定着装置
２ ベルト
３ 加熱ローラ
４ 加圧ローラ
５ テンションローラ
６ 冷却装置[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electrophotographic image-receiving sheet and an image forming method, and in particular, oilless fixing is possible, and even when left in a high-humidity environment, the glossiness of a white background portion is small, and the blocking resistance and brittleness are reduced. The present invention relates to an excellent electrophotographic image receiving sheet having high image quality and an image forming method using the electrophotographic image receiving sheet.
[0002]
[Prior art]
Conventionally, the electrophotographic method has been used for copying machines and PC output machines because it can be printed on general-purpose paper (plain paper and high-quality paper) by dry processing and has a high printing speed. When image information such as image data is output as a photograph, special-purpose paper for photographic use is required because general-purpose paper or the like is particularly inferior in gloss or feels different from a photograph.
[0003]
In order to meet the above requirements and to obtain special paper having excellent gloss, an electrophotographic image receiving sheet provided with a toner image receiving layer containing a thermoplastic resin on a support has been proposed (for example, Patent Document 1 and Patent Document 1). 2). In addition, an electrophotographic image receiving sheet using a support in which a thermoplastic resin layer is provided on the front and back surfaces of a base paper has been proposed in order to bring the feel closer to a photograph (see, for example, Patent Document 3).
In recent years, a technique for providing releasability to the heat roller of the fixing unit by adding wax, a silicone compound, or the like to the toner has been proposed, and oilless machines that do not use fixing oil and are easy to maintain have begun to spread. Yes.
[0004]
However, the toner image-receiving layer containing the thermoplastic resin as described above has a problem that when an oilless machine without fixing oil is used, the toner image-receiving layer is easily offset and easily causes a conveyance failure. For this reason, the technique using the additive which has a mold release effect in a thermoplastic resin layer is proposed (for example, refer patent documents 4-7). However, these proposals have a problem that, when stored in a high humidity environment, the glossiness is lowered and the feeling is greatly different from that of photographs.
That is, the decrease in glossiness is most noticeable in the white background, suggesting that it is caused by the electrophotographic image-receiving sheet. Further, from the surface observation, it is not observed as a change in unevenness, and there is a high possibility that it is a change in the refractive index of the surface. This is presumed to be caused by swimming of the release agent contained in the electrophotographic image-receiving sheet or by crystallization of the release agent swimming on the surface. It was essential and usually difficult to remove.
[0005]
[Patent Document 1]
JP-A-4-212168
[Patent Document 2]
Japanese Patent Laid-Open No. 8-21645
[Patent Document 3]
Japanese Patent Laid-Open No. 8-21645
[Patent Document 4]
JP-A-11-52604
[Patent Document 5]
Japanese Patent Laid-Open No. 11-52605
[Patent Document 6]
JP-A-11-52606
[Patent Document 7]
JP 11-212292 A
[0006]
[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 is capable of oil-less fixing, has little reduction in glossiness of a white background portion even when left in a high humidity environment, and has a high-quality electrophotographic image-receiving sheet excellent in blocking resistance and brittleness. An object of the present invention is to provide an image forming method using the electrophotographic image receiving sheet.
[0007]
[Means for Solving the Problems]
  Means for solving the problems are as follows. That is,
<1> having at least one toner image-receiving layer on the support;The toner image-receiving layer contains carnauba wax and polyethylene oxide which is a water-soluble polymer having a nonionic polar group, and the mixing mass ratio (carnauba wax: polyethylene oxide) of the carnauba wax to the polyethylene oxide is 1: The electrophotographic image-receiving sheet is 0.1 to 10.
<2>It has a toner image-receiving layer having a laminated structure of two or more layers on the support, contains carnauba wax in the outermost surface layer of the toner image-receiving layer, and has nonionic polar groups in layers other than the outermost surface layer. An electrophotographic image-receiving sheet comprising polyethylene oxide which is a water-soluble polymer.
<3>A toner image-receiving layer having a laminated structure of two or more layers is provided on a support, and carnauba wax is included in the outermost surface layer of the toner image-receiving layer, and layers other than the outermost surface layer and the outermost surface layer of the toner image-receiving layer An electrophotographic image-receiving sheet characterized in that it contains polyethylene oxide, which is a water-soluble polymer having a nonionic polar group.
<4>The total mass ratio of carnauba wax and polyethylene oxide (carnauba wax: polyethylene oxide) in the toner image-receiving layer having two or more layers is 1: 0.1 to 10.<2> or <3>The electrophotographic image-receiving sheet described in 1.
<5>The electrophotographic image-receiving sheet according to any one of <1> to <4>, wherein the polyethylene oxide has an average molecular weight of 10,000 or more.
<6>An image forming method using the electrophotographic image-receiving sheet according to any one of <1> to <5>, wherein a toner image is formed on the electrophotographic image-receiving sheet, and then the electrophotographic image-receiving sheet The image forming surface is heated and pressed by a fixing belt and a fixing roller, cooled, and then peeled off from the fixing belt.
<7>An image forming method using the electrophotographic image receiving sheet according to any one of <1> to <5>, wherein a toner image is formed on the electrophotographic image receiving sheet and then fixed by a heat roller. Further, the image forming method is characterized in that the image forming surface of the electrophotographic image receiving sheet is heated and pressed by a fixing belt and a fixing roller, cooled, and then peeled off from the fixing belt.
<8>The image forming method according to <6> or <7>, wherein a fluorocarbonsiloxane rubber layer having a uniform thickness is provided on a surface of the fixing belt.
<9>The image according to <6> or <7>, wherein the surface of the fixing belt has a silicone rubber layer having a uniform thickness, and the surface of the silicone rubber layer is provided with a layer made of a fluorocarbon siloxane rubber. It is a forming method.
<10>The image forming method according to <8> or <9>, wherein the fluorocarbon siloxane rubber has a perfluoroalkyl ether group and / or a perfluoroalkyl group in a main chain.
[0008]
  The electrophotographic image-receiving sheet of the present invention is, as a first aspect, the toner image-receiving layer,Carnauba waxAnd a water-soluble polymer having a nonionic polar groupPolyethylene oxideincluding. The electrophotographic image-receiving sheet of the present invention, as a second aspect, is a toner image-receiving layer having a laminated structure of two or more layers, the outermost surface layer of the toner image-receiving layer beingCarnauba waxAs a water-soluble polymer having a nonionic polar group in a layer other than the outermost surface layerPolyethylene oxideContaining. The electrophotographic image-receiving sheet of the present invention is a toner image-receiving layer having a laminated structure of two or more layers as a third aspect, and is provided on the outermost surface layer of the toner image-receiving layer.Carnauba waxA water-soluble polymer having a nonionic polar group in the outermost surface layer of the toner image-receiving layer and in a layer other than the outermost surface layerPolyethylene oxideContaining. In the electrophotographic image receiving sheets of the first to third aspects,Carnauba waxAnd water-soluble polymers with nonionic polar groupsPolyethylene oxideBy using both of these, the dissolution effect or the diffusion suppressing effect of the wax (by itself or partly low molecular weight component) by the water-soluble polymer works, and the wax bleeds out to the surface even when left in a high humidity environment. Therefore, a high-quality electrophotographic image-receiving sheet excellent in blocking resistance and brittleness can be obtained with little decrease in glossiness of the white background portion.
[0009]
The image forming method of the present invention uses the electrophotographic image receiving sheet of the present invention, forms a toner image on the electrophotographic image receiving sheet, and then fixes the image forming surface of the electrophotographic image receiving sheet. After being heated and pressed by a belt and a fixing roller, cooled, and then peeled off from the fixing belt. As a result, even if an oilless machine without fixing oil is used, the image receiving sheet paper and toner can be prevented from being peeled off or the image receiving paper and toner components can be prevented from being offset. It is possible to realize a good image having good glossiness and rich in photographic feeling.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
<Electrophotographic image-receiving sheet>
The electrophotographic image-receiving sheet has a support and at least one toner image-receiving layer provided on at least one surface of the support, and other layers appropriately selected as necessary, for example, a surface protective layer, It comprises an intermediate layer, an undercoat layer, a cushion layer, a charge control (prevention) layer, a reflective layer, a tint preparation layer, a storage stability improving layer, an adhesion prevention layer, an anti-curl layer, a smoothing layer and the like. Each of these layers may have a single layer structure or a laminated structure.
[0011]
[Support]
Examples of the support include base paper, synthetic paper, synthetic resin sheet, coated paper, and laminated paper. These supports may have a single layer structure or a laminated structure of two or more layers.
[0012]
-Base paper-
As raw materials for the base paper, those used for known base paper as those used for the support are not particularly limited, and can be selected from various materials. For example, natural pulp selected from conifers and hardwoods, synthetic pulp made of plastic materials such as polyethylene and polypropylene, or a mixture of natural pulp and synthetic pulp can be used.
[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. Although desirable, softwood bleached kraft pulp (NBKP), hardwood sulfite pulp (LBSP) and the like can also be used.
As the pulp fiber, it is appropriate to mainly use hardwood pulp having a short fiber length.
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 a wet agent are used as necessary. A paper strength enhancer, a fixing agent, a pH adjuster, and other agents are added.
[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 and the like, and further higher fatty acids such as alkyl ketene dimer, alkenyl succinic anhydride (ASA) and epoxidized fatty acid amide. Examples thereof include compounds.
[0015]
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. Examples of other chemicals include antifoaming agents, dyes, slime control agents, fluorescent whitening agents, and the like.
Moreover, a softening agent etc. can also be added as needed. The softening agent is described in, for example, New Paper Processing Handbook (edited by Paper Medicine Time), pages 554 to 555 (issued in 1980).
[0016]
The treatment liquid used for the surface sizing treatment may contain, for example, a water-soluble polymer, a sizing agent, a water-resistant substance, a pigment, a pH adjusting agent, a dye, and a fluorescent brightening agent. 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, styrene-maleic anhydride copolymer sodium salt, Examples thereof include sodium polystyrene sulfonate.
[0017]
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.
Examples of base paper materials include synthetic pulp paper, mixed paper of natural pulp and synthetic pulp, and various types of combined paper, in addition to the above-described natural pulp paper.
[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]
In the present invention, the Wangken smoothness of the surface of the base paper on the toner image-receiving layer side is 210 seconds or 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. The upper limit is not particularly limited, but is practically about 600 seconds, preferably about 500 seconds.
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 paper “strain” differs based on the difference in beating style, and after beating, the elasticity (rate) of the paper made from paper is an important factor that represents the degree of paper “strain”. 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 thickness of the base paper is usually 30 to 500 μm, preferably 50 to 300 μm, more preferably 100 to 250 μm. The basis weight of the base paper is preferably 50 to 250 g / m, for example.², More preferably 100 to 200 g / m²It is preferable that it exists in the range.
[0023]
Specific examples of the base paper include high-quality paper and, for example, “Photographic Engineering Basics—Silver Salt Photography” edited by the Japan Photography Society, published by Corona Co., Ltd. (Showa 54) (223) to (240). The papers described are suitable.
[0024]
In order to impart a desired centerline average roughness to the surface of the base paper, for example, as disclosed in JP-A-58-68037, a fiber length distribution (for example, a 24 mesh screen residue and , 42 mesh screen residue is preferably 20% by mass to 45% by mass, and 24 mesh screen residue is preferably 5% by mass or less. Further, the center line average roughness can be adjusted by applying heat and pressure to the surface with a machine calendar, a super calendar, or the like.
[0025]
-Synthetic paper-
The synthetic paper is paper mainly composed of polymer fibers other than cellulose, and examples of the polymer fibers include polyolefin fibers such as polyethylene and polypropylene.
[0026]
-Synthetic resin sheet (film)-
Examples of the synthetic resin sheet (film) include those obtained by forming a synthetic resin into a sheet shape, such as polypropylene, stretched polyethylene, stretched polypropylene, polyester film, stretched polyester, nylon film, stretched white film, Examples include a white film containing a white pigment.
[0027]
-Coated paper-
The coated paper is a paper obtained by coating various sheets of resin, rubber latex, or polymer material on one side or both sides of a sheet such as a base paper, and the coating amount varies depending on the application. Examples of such coated paper include art paper, cast coated paper, Yankee paper, and the like.
[0028]
As the resin applied to the surface of the base paper or the like, it is appropriate to use a thermoplastic resin. Examples of such a thermoplastic resin include the following thermoplastic resins (a) to (h).
[0029]
(A) Polyolefin resins such as polyethylene resins and polypropylene resins, copolymer resins of olefins such as ethylene and propylene and other vinyl monomers, acrylic resins, and the like.
(B) A thermoplastic resin having an ester bond. For example, a dicarboxylic acid component (these dicarboxylic acid components may be substituted with a sulfonic acid group, a carboxyl group, etc.) and an alcohol component (these alcohol components may be substituted with a hydroxyl group, etc.) Polyester resin, polymethyl methacrylate, polybutyl methacrylate, polymethyl acrylate, polybutyl acrylate and other polyacrylic acid ester resins or polymethacrylic acid ester resins, polycarbonate resins, polyvinyl acetate resins, styrene acrylate resins, styrene -Methacrylic acid ester copolymer resin, vinyl toluene acrylate resin, etc. are mentioned.
Specific examples include those described in JP-A Nos. 59-101395, 63-7971, 63-7972, 63-7773, and 60-294862. it can.
Commercially available products include Byron 290, Byron 200, Byron 280, Byron 300, Byron 103, Byron GK-140, Byron GK-130 manufactured by Toyobo; Kao Tufton NE-382, Tufton U-5, ATR- 2009, ATR-2010; Unitika's Elitel UE3500, UE3210, XA-8153, KZA-7049, KZA-1449; Nippon Synthetic Chemical Polyester TP-220, R-188; And various thermoplastic resins.
[0030]
(C) Polyurethane resin etc. are mentioned.
(D) Polyamide resin, urea resin, etc. are mentioned.
(E) Polysulfone resin and the like.
(F) Polyvinyl chloride resin, polyvinylidene chloride resin, vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl propionate copolymer resin, and the like.
(G) Cellulose resins, such as polyol resin, ethyl cellulose resin, cellulose acetate resin, etc., such as polyvinyl butyral.
(H) Polycaprolactone resin, styrene-maleic anhydride resin, polyacrylonitrile resin, polyether resin, epoxy resin, phenol resin and the like.
In addition, the said thermoplastic resin may be used individually by 1 type, and may use 2 or more types together.
[0031]
Further, the resin may contain a brightening agent, a conductive agent, a filler, a pigment such as titanium oxide, ultramarine blue, carbon black, or a dye, if necessary.
[0032]
-Laminated paper-
The laminated paper is a paper obtained by laminating various resins, rubber or polymer sheets or films on a sheet such as a base paper. Examples of the laminate material include polyolefin, polyvinyl chloride, polyethylene terephthalate, polystyrene, polymethacrylate, polycarbonate, polyimide, triacetyl cellulose, and the like. These resins may be used alone or in combination of two or more.
[0033]
In general, the polyolefin is often formed using low density polyethylene, but in order to improve the heat resistance of the support, polypropylene, a blend of polypropylene and polyethylene, high density polyethylene, high density polyethylene and low density polyethylene, It is preferable to use a blend of In particular, it is most preferable to use a blend of high-density polyethylene and low-density polyethylene from the viewpoint of cost, suitability for lamination, and the like.
[0034]
The blend of the high density polyethylene and the low density polyethylene is used, for example, in a blend ratio (mass ratio) of 1/9 to 9/1. The blend ratio is preferably 2/8 to 8/2, and more preferably 3/7 to 7/3. When forming a thermoplastic resin layer on both surfaces of the support, the back surface of the support is preferably formed using, for example, high-density polyethylene or a blend of high-density polyethylene and low-density polyethylene. The molecular weight of polyethylene is not particularly limited, but the melt index is 1.0 to 40 g / 10 min for both high-density polyethylene and low-density polyethylene and has extrudability. preferable.
In addition, you may perform the process which gives white reflectivity to these sheets or films. Examples of such a treatment method include a method of blending a pigment such as titanium oxide in these sheets or films.
[0035]
The thickness of the support is preferably 25 μm to 300 μm, more preferably 50 μm to 260 μm, and still more preferably 75 μm to 220 μm. Various stiffnesses can be used according to the purpose, and the support for a photographic image receiving sheet for electrophotography is close to a support for color silver halide photography. Those are preferred.
[0036]
<Toner image-receiving layer>
  The toner image-receiving layer is a first aspect,Carnauba waxAnd a water-soluble polymer having a nonionic polar groupPolyethylene oxideContaining. As a result, it is possible to provide a high-quality electrophotographic image-receiving sheet that can be fixed in oilless and has little reduction in glossiness of the white background. In this case, in the toner image receiving layerCarnauba waxAnd a water-soluble polymer having a nonionic polar groupPolyethylene oxideThe mixing mass ratio (wax: water-soluble polymer having a nonionic polar group) is preferably 1: 0.1 to 10, more preferably 1: 1 to 5.
[0037]
  As a second aspect, the toner image receiving layer is a toner image receiving layer having a laminated structure of two or more layers, and is formed on the outermost surface layer of the toner image receiving layer.Carbana waxAs a water-soluble polymer having a nonionic polar group in a layer other than the outermost surface layer.Polyethylene oxideContaining.
  Further, as a third aspect, the toner image receiving layer is a toner image receiving layer having a laminated structure of two or more layers, and is formed on the outermost surface layer of the toner image receiving layer.Carbana waxAs a water-soluble polymer having a nonionic polar group in the outermost surface layer of the toner image-receiving layer and in a layer other than the outermost surface layer.Polyethylene oxideContaining.
  According to the toner image-receiving layers of the second and third aspects, the toner image-receiving layer has a multilayer structure, and is formed on the outermost surface layer.Carbana waxIn the case where it contains, since it is possible to prevent the bleed out of the wax even when left in a high humidity environment, it is possible to provide a high-quality electrophotographic image-receiving sheet with little reduction in glossiness of the white background portion.
  In this case, in the toner image receiving layer having a laminated structure of two or more layers.Carbana waxAnd water-soluble polymers with nonionic polar groupsPolyethylene oxideAnd the total mass ratio (wax:Polyethylene oxide) Is preferably 1: 0.1 to 10, more preferably 1: 1 to 5.
[0038]
  In the present invention, the wax contained in the toner image-receiving layer is carnauba wax, and the water-soluble polymer having a nonionic polar group is polyethylene oxide.It is.By using carnauba wax and polyethylene oxide in combination, the wax does not bleed out to the surface even when left in a high-humidity environment, there is little loss of glossiness on white areas, and high image quality with excellent blocking resistance and brittleness An electrophotographic image-receiving sheet can be obtained. Furthermore, polyethylene oxide is suitable for thickening and stabilizing a latex (in particular, a latex having a carboxylic acid residue and self-dispersing is preferable).
[0039]
-Wax-
  The waxasFor example, petroleum wax, modified wax, hydrogenated wax, vegetable wax, animal wax, mineral wax, synthetic hydrocarbon, modified wax, hydrogenated wax, etc., among these, fatty acid ester wax, Polyethylene wax, etc.Is.The wax of the present invention is carnauba wax.
[0040]
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 ° Fin, 135 ° paraffin, 135 ° H, 140 ° paraffin, 140 ° N, 145 ° paraffin, paraffin wax M, etc .; microcrystalline wax (Hi-Mic-2095, Hi-Mic-3090 manufactured by Nippon Seiki as commercial products) , 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; Petroleum (Nippon Seiki OX-1749, OX-0450, OX-0650B, OX-0153, OX-261BN, OX-0551, OX-0550, OX as commercially available products) -0750B, JP- 500, JP-056R, JP-011P, etc.); Fischer-Tropsch wax (commercially available products such as FT100, FT-0070 manufactured by Nippon Seiki); acid amide compounds or acid imide compounds (specifically, stearic acid amide, phthalic anhydride) Examples of commercially available products such as acid imide include Chukyo Oil & Fats Cellosol 920, B-495, Hymicron G-270, G-110, Hydrin D-757, and the like.
Examples of the modified wax include amine-modified polypropylene (QN-7700 manufactured by Sanyo Chemical Co., Ltd. as a commercial product), acrylic acid-modified, 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.
Examples of the hydrogenated wax include hydrogenated castor oil (such as a castor wax manufactured by Ito Oil Co., Ltd.), castor oil derivatives (dehydrated castor oil DCO, DCO Z-1, DCO Z-3, castor oil fatty acid manufactured by Ito Oil Co., Ltd. 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), heptyl 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), and synthetic waxes such as cyclopentadiene oil (commercially available products such as CP oil and CP oil-S made by Ito Oil). .
[0041]
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.
Examples of the animal wax include beeswax, lanolin, spermaceti, stew wax (whale oil), and wool wax.
Examples of the mineral wax include natural waxes such as montan wax, montan ester wax, ozokerite, and ceresin, and fatty acid esters (commercially available products such as Sanso Sizer DOA, AN-800, DINA, DIDA, DOZ, manufactured by Shin Nippon Rika). DOS, TOTM, TITM, E-PS, nE-PS, E-PO, E-4030, E-6000, E-2000H, E-9000H, TCP, C-1100, etc.).
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 (Sanyo Kasei Biscol 330-P, 550-P, 660-P), Fischer-Tropsch wax (Nippon Seiki FT100, FT-0070, etc.) Amide compounds or acid imide compounds (specifically, stearamide, 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.
Examples of the modified wax include amine-modified polypropylene (QN-7700 manufactured by Sanyo Chemical Co., Ltd. as a commercial product), acrylic acid-modified, fluorine-modified, olefin-modified wax, and urethane type wax (NPS-6010 manufactured by Nippon Seiki Co., Ltd. as a commercial product). -5090), alcohol type wax (NPS-9210, NPS-9215, OX-1949, XO-020T, etc., manufactured by Nippon Seiki) and the like.
Examples of the hydrogenated wax include hardened castor oil (as a commercially available product, castor wax from Ito Oil Co., Ltd.), castor oil derivatives (dehydrated castor oil DCO, DCO Z-1, DCO Z-3, castor from Ito Oil as commercial products). Oil fatty acid 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 MINERASOL RC-2, RC-17, RC-55, RC-335, Special castor oil-based condensed fatty acid ester MINERASOL LB-601, LB-603, LB-604, LB-702, L B-703, # 11, L-164, etc.), stearic acid (12-hydroxystearic acid made by Ito Oil as a commercial product), lauric acid, myristic acid, palmitic acid, behenic acid, sebacic acid (as commercial products) Sebacic acid from Ito Oil), undecylenic acid (such as undecylenic acid from Ito Oil as a commercial product), heptylic acid (such as heptyl acid from Ito Oil as a commercial product), maleic acid, highly maleated oil (as a commercial product) HIMALIN DC-15, LN-10, 00-15, DF-20, SF-20, etc., manufactured by Ito Oil Co., Ltd., blown oil (commercially available, Celbonol # 10, # 30, # 60, R-40 manufactured by Ito Oil Co., Ltd.) , S-7, etc.), cyclopentadiene oils (commercially available products such as CP oil and CP oil-S made by Ito Oil) And the like.
[0042]
In addition, these derivatives, oxides, purified products, and mixtures can also be used as the wax. Moreover, these may have a reactive substituent.
[0043]
  Used in the present inventionCarnauba waxThe amount is 1 to 20% by mass, preferably 2 to 10% by mass, based on the mass of the toner image-receiving layer.
[0044]
-Water-soluble polymer having nonionic polar group-
  The water-soluble polymer having a nonionic polar group of the present invention is polyethylene oxide. Among these, polyethylene oxide having an average molecular weight of 10,000 or more is preferable, and polyethylene oxide having an average molecular weight of 100,000 or more is more preferable.
[0045]
  Water-soluble polymer having nonionic polar group used in the present inventionPolyethylene oxideThe amount is 1 to 20% by mass, preferably 2 to 10% by mass, based on the mass of the toner image-receiving layer.
[0046]
-Thermoplastic resin-
The toner image receiving layer preferably contains a thermoplastic resin. The thermoplastic resin is not particularly limited as long as it can be deformed under temperature conditions such as fixing and can accept the toner, and can be appropriately selected according to the purpose. And the same type of resins are preferred. In many of the toners, polyester resins, copolymer resins such as styrene and styrene-butyl acrylate are used. In this case, polyester resins, styrene, styrene are also used as the thermoplastic resins used in the electrophotographic image-receiving sheet. -It is preferable to use a copolymer resin such as butyl acrylate, more preferably 20% by mass or more of a copolymer resin such as polyester resin, styrene, or styrene-butyl acrylate. Polymers, styrene-acrylic acid ester copolymers, styrene-methacrylic acid ester copolymers and the like are also preferable.
[0047]
Specific examples of the thermoplastic resin include, for example, (a) a resin having an ester bond, (b) a polyurethane resin, (c) a polyamide resin, (d) a polysulfone resin, (e) a polyvinyl chloride resin, and the like. (F) Polyvinyl butyral, (g) Polycaprolactone resin, (h) Polyolefin resin, and the like.
[0048]
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 adduct, bisphenol A propylene oxide 2 adduct, etc.), bisphenol S, 2-ethylcyclohexyldimethanol, neopentylglycol, cyclohexyldimethanol, glycerin, etc. Polyester resins obtained by condensation with components (hydroxyl groups may be substituted on these alcohol components), polyacrylic ester resins such as polymethyl methacrylate, polybutyl methacrylate, polymethyl acrylate, polybutyl acrylate, etc. Examples thereof include polymethacrylate resin, polycarbonate resin, polyvinyl acetate resin, styrene acrylate resin, styrene-methacrylate copolymer resin, and vinyl toluene acrylate resin.
Specific examples include those described in JP-A Nos. 59-101395, 63-7971, 63-7972, 63-7773, and 60-294862.
[0049]
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.
[0050]
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 (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., Ltd. 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.
[0051]
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.
[0052]
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.
[0053]
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.
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.
[0054]
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.
[0055]
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, vinyl pyrrolidone-vinyl acetate copolymer, styrene-vinyl pyrrolidone 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 products include water-soluble polyester plus coats manufactured by Tateo Chemical Industry Co., Ltd., Dainippon Ink and Chemicals Finetex ES series, water-soluble acrylics Jurimer AT Series made by Dainippon Ink and Dainippon Ink and Chemicals Fine Examples include Tex 6161, K-96, Hiros NL-1189, BH-997L manufactured by Seiko Chemical Industry.
[0056]
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's Pesresin A series, Kao's Tufton UE series, Nippon Synthetic Polyester WR series, Unitika's Eliere series, and acrylic series. Then, high loss XE, KE, PE series made by Seiko Chemical Industry, Jurimer ET series made by Nippon Pure Chemical Co., Ltd., etc. are 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.
[0057]
In the present invention, it is preferable to use a self-dispersing water-based polyester resin emulsion that satisfies the following characteristics (1) to (4) as the thermoplastic resin. Since this is a self-dispersion type that does not use a surfactant, it has low hygroscopicity even in a high humidity atmosphere, and there is little decrease in the softening point due to moisture, and it is possible to suppress the occurrence of offset during fixing and the failure of adhesion between sheets during storage. In addition, it is environmentally friendly and workable because it is aqueous. Furthermore, since a polyester resin having a high cohesive energy and a molecular structure is used, it has a sufficient hardness in the storage environment, but becomes a low elastic (low viscosity) molten state in the fixing process of electrophotography, and the toner becomes a toner. A sufficient image quality can be achieved by being embedded in the image receiving layer.
(1) The number average molecular weight (Mn) is preferably 5,000 to 10,000, and more preferably 5,000 to 7,000.
(2) The molecular weight distribution (weight average molecular weight / number average molecular weight) is preferably ≦ 4, and more preferably Mw / Mn ≦ 3.
(3) The glass transition temperature (Tg) is preferably 40 to 100 ° C, more preferably 50 to 80 ° C.
(4) The volume average particle diameter is preferably 20 to 200 nmφ, more preferably 40 to 150 mmφ.
[0058]
In the toner image-receiving layer, as components other than the thermoplastic resin and wax, the light transmittance of the image-receiving layer can be easily adjusted within the numerical range, and in particular, the whiteness of the image-receiving layer can be adjusted. Colorants such as pigments and dyes are preferred, and pigments are particularly preferred. In addition to the above, the other components include various additives added for the purpose of improving the thermodynamic properties of the toner image-receiving layer, such as plasticizers, mold release agents or slip agents (excluding wax), Matting agents, fillers, crosslinking agents, charge control agents, emulsions, dispersions and the like can be mentioned.
[0059]
-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.
[0060]
An inorganic pigment (titanium oxide, calcium carbonate, etc.) can be used as the white pigment. Examples of colored pigments include various pigments and azo pigments described in JP-A-63-44653 (Azo lake; Carmine 6B, Red 2B, Insoluble azo; Monoazo yellow, Disazo yellow, Pyrazolo orange, Vulcan orange, Condensed azo type) Chromophthalier, chromophthaled red), polycyclic pigments (phthalocyanine series; copper phthalocyanine blue, copper phthalocyanine green, dioxazine series; dioxazine violet, isoindolinone series; isoindolinone yellow, slen series; perylene, perinone, Flavantron, thioindigo, lake pigment (malachite green, rhodamine B, rhodamine G, Victoria blue B) or inorganic pigment (oxide, titanium dioxide, bengara, sulfate; precipitated barium sulfate, carbonate; precipitated calcium carbonate, Hydrous succinate, anhydrous succinate, metal powder: aluminum powder, bronze powder, zinc powder, carbon black, chrome lead, bitumen, etc. These may be used alone, Two or more of these may be used in combination, and among these, titanium oxide is particularly preferable as the pigment.
[0061]
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, C.I. 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, C.I. 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. There are oil-soluble dyes such as Solvent Blue 55.
[0062]
Further, a colored coupler used in silver salt photography can also be preferably used.
[0063]
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 is 0.1 g / m²If it is less than 1, the light transmittance in the toner image-receiving layer is increased, while 8 g / m.²Exceeding may cause poor handling such as cracking and adhesion resistance.
[0064]
-Release agent (excluding wax)-
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 a silicone compound, a fluorine compound, and a matting agent.
[0065]
Specifically, as the mold release agent used in the present invention, for example, compounds described in “Summary and Application of Revision Wax” by Kosho Shobo and Silicone Handbook published by Nikkan Kogyo Shimbun, Inc. can be used. JP-B-59-38581, JP-B-4-32380, Japanese 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, 11-65156, 11-73049, and 11-194542. A plurality of these compounds can be used in combination.
[0066]
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, F-3800 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, TSF4702, 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. Cymac 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, TE2175, 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.
[0067]
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 resins (Nippon Yushi Modiper F200, F220, F600, F2020, F3035; Dainichi Seika's 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.).
[0068]
Content (g / m) of the release agent (excluding 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 the release agent is too large, and the image quality of the formed image may be inferior.
[0069]
-Matting agent-
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.
[0070]
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.
[0071]
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 poly (meth) acrylic acid esters (for example, polyalkyl (meth) acrylate, polyalkoxyalkyl (meth) acrylate, polyglycidyl (meth) acrylate), poly (meth) Includes acrylamide, polyvinyl ester (eg, polyvinyl acetate), polyacrylonitrile, polyolefin (eg, polyethylene), polystyrene, benzoguanamine resin, formaldehyde condensation polymer, epoxy resin, polyamide, polycarbonate, phenol resin, polyvinyl carbazole and polyvinylidene chloride .
You may use the copolymer which combined the monomer used for the above polymer.
[0072]
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. Patent No. 1,939,213, No. 2221873, No. 2,268,662, No. 2322037, No. 2376005, No. 233911, No. 2701245, No. 2992101, No. 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 What has been described.
Two or more kinds of solid particles may be used in combination. The average particle diameter of the solid particles is, for example, 1 to 100 μm, preferably 4 to 30 μm. The amount of solid particles used is 0.01 to 0.5 g / m.², Preferably 0.02 to 0.3 g / m²It is appropriate that
[0073]
-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-" (edited by Koichi Murai, Koshobo), "Research on plasticizer" "Study under" (edited by Polymer Chemistry Association) and "Handbook Rubber and Plastic Compounded Chemicals" (edited by Rubber Digest Co., Ltd.).
[0074]
Some of the plasticizers are described as high-boiling organic solvents and 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- No. 30247, 62-136646, JP-A-2-235694, and the like (for example, Tarates, phosphates, 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, glycols 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, 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.
[0075]
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 15000 or less, 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 and 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, pentalin 4851, FK115, 4820, 830, Louisol 28-JA, picolastic A75, pico Examples include Tex LC and Crystallex 3085.
[0076]
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).
[0077]
-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 Basics and Applications" (Taiseisha), "Filler Handbook" (Taiseisha) 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, lead white, 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. Moreover, as said filler, a thing with a small particle size is preferable. If the particle size is large, the surface of the toner image-receiving layer tends to be roughened.
[0078]
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. As an average particle diameter of a silica, 4-120 nm is preferable and 4-90 nm is more preferable.
The silica is preferably porous. The average pore diameter of the porous silica is preferably 50 to 500 nm. Moreover, the average pore volume per mass of the porous silica is preferably, for example, 0.5 to 3 ml / g.
[0079]
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. As an average particle diameter of an alumina, 4-300 nm is preferable and 4-200 nm is more preferable. 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.
[0080]
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.
It is preferable that the said filler is 5-2000 mass% based on the dry mass of the binder of the layer to add.
[0081]
-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, an epoxy group as a reactive group, an isocyanate group, an aldehyde group, an active halogen group, an active methylene group, an acetylene group, or a compound having two or more known reactive groups in the molecule is used.
[0082]
As the crosslinking agent, a compound having two or more groups capable of forming a bond by a hydrogen bond, an ionic bond, a coordinate 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) The publicly known thing mentioned by the company edition) etc. can be used.
[0083]
-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.
[0084]
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. In addition, the metal oxide may further contain a different element, for example, Al, In, etc. with respect to ZnO, such as TiO.₂Nb, Ta, etc., SnO₂Can contain (doping) Sb, Nb, a halogen element, or the like.
[0085]
-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. Additives for this purpose include various known antioxidants, anti-aging agents, anti-aging agents, anti-ozone deterioration agents, ultraviolet absorbers, metal complexes, light stabilizers, antiseptics, fungicides, etc. Can be mentioned.
[0086]
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.
[0087]
Examples of the antiaging agent include those described in “Handbook Rubber / Plastic Compounding Chemicals Revised 2nd Edition” (1993, Rubber Digest Co.) p76-121.
[0088]
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).
[0089]
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.
[0090]
As described above, known photographic additives can be added to the material that can be used in the toner image-receiving layer of the present invention. As photographic additives, for example, Research Disclosure Magazine (hereinafter abbreviated as RD) No. 17643 (December 1978), No. 1 18716 (November 1979) and 307105 (November 1989), and the corresponding parts are summarized below.

[0091]
[Physical properties of toner image-receiving layer]
The toner image-receiving layer has a 180-degree peel strength at a fixing temperature with a fixing member of 0.1 N / 25 mm or less, more preferably 0.041 N / 25 mm or less. The 180 degree peel strength can be measured in accordance with 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, it is preferable that the spectral reflectance is 85% or more in the wavelength region of 440 nm to 640 nm and the difference between the maximum spectral reflectance and the minimum spectral reflectance in the same wavelength region is within 5%. Furthermore, it is more preferable that the spectral reflectance is 85% or more in the wavelength range of 400 nm to 700 nm, and the difference between the maximum spectral reflectance and the minimum spectral reflectance in the same wavelength range is within 5%.
Further, as the whiteness, specifically, CIE 1976 (L^*a^*b^*) In color space, L^*The value is preferably 80 or more, preferably 85 or more, and 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^*)²Is preferably 50 or less, more preferably 18 or less, and even more preferably 5 or less.
[0092]
The toner image receiving layer preferably has high gloss. The glossiness is preferably 60 or more, more preferably 75 or more, and even 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.
[0093]
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 more preferably 0.5 μm or less in the entire region from white without toner to black having the maximum density. More preferably.
The arithmetic average roughness can be measured based on JIS B 0601, B 0651, B 0652.
[0094]
The toner image-receiving layer preferably has physical properties of one of 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 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 between 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, 10-239889, and the like. .
[0095]
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.
[0096]
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 the ratio 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 obtained toner image tends to be low, while the surface electrical resistance is 1 × 10.¹⁵Ω / cm²Exceeding the amount of charge will generate more charge than necessary during transfer, the toner will not be transferred sufficiently, the image density will be low, and electrostatic charge will easily adhere to the electrophotographic image receiving sheet, and during copying, Misfeed, double feed, discharge mark, toner transfer missing, etc. may occur.
[0097]
The surface electrical resistance of the surface opposite to the toner image-receiving layer with respect to the support is 5 × 10.⁸~ 3.2 × 10¹⁰Ω / cm²1 × 10 is preferred⁹~ 1x10¹⁰Ω / cm²Is more preferable.
In the present invention, the surface electrical resistance is measured in accordance with 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 under the same environment, R8340 manufactured by Advantest Corporation. Is used, and measurement is performed after 1 minute has passed after energization under the condition of an applied voltage of 100V.
[0098]
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, 1 to 50 μm, preferably 5 to 15 μm.
[0099]
[Other layers]
Examples of the other layers include a surface protective layer, a back layer, an intermediate layer, an adhesion improving layer, an undercoat layer, a cushion layer, a charge control (prevention) layer, a reflective layer, a tint adjusting layer, a storage stability improving layer, and an adhesive. Examples include a prevention 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.
[0100]
-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.
[0101]
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.
[0102]
-Back layer-
In the electrophotographic image-receiving sheet of the present invention, the back layer is on the opposite side of the toner image-receiving layer from the support for the purpose of imparting backside output suitability, improving backside output image quality, improving curl balance, improving device passability, etc. Is preferably provided.
The color of the back layer is not particularly limited, but when the electrophotographic image-receiving sheet of the present invention is a double-sided output type image-receiving paper that forms an image on the back surface, the back layer is preferably 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.
[0103]
-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.
[0104]
-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.
[0105]
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.
[0106]
<Toner>
The electrophotographic image-receiving sheet of the present invention is used by allowing a toner image-receiving layer to receive 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.
[0107]
-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.
[0108]
-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.
[0109]
-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 polyethylene wax having a molecular weight of 1000 or less is particularly effective, and a range of 300 to 1000 is more preferable.
[0110]
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
[0111]
Specific examples of the raw material compound include monoisocyanate compounds such as dodecyl isocyanate, phenyl isocyanate and derivatives thereof, naphthyl isocyanate, hexyl isocyanate, benzyl isocyanate, butyl isocyanate, and allyl isocyanate. It is done.
Examples of diisocyanate compounds 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.
[0112]
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.
[0113]
-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.
[0114]
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.
[0115]
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.
[0116]
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.
[0117]
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 powders, such as fatty acid or its derivative (s), these metal salts, fluorine resin, a polyethylene resin, an acrylic resin, can be used. The average particle diameter of these powders is, for example, 0.01-5 μm, preferably 0.1-2 μm.
[0118]
The method for producing the toner is not particularly limited, and (i) a step of forming an aggregated particle 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 the 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.
[0119]
-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 diameter 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 at least 0.95.
In addition, the toner of the present invention preferably satisfies the volume average particle diameter range of the toner and has an average value of a shape factor represented by the following formula of 1.00 to 1.50.
Shape factor = [π × (2 × L)²] / (4 × S)
(However, L represents the maximum radius 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. Also, it is difficult to cause omission and blur due to transfer, and handling properties are hardly adversely affected even if the average particle size is not small. Become.
[0120]
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.
[0121]
<Image forming method>
The toner is transferred onto the electrophotographic image receiving material of the present invention, and the toner is fixed on the toner image receiving layer on the image receiving material to form an image.
In the image forming method of the present invention, as a first aspect, after a toner image is formed on the electrophotographic image receiving sheet, the image forming surface of the electrophotographic image receiving sheet is heated by a fixing belt and a fixing roller. And after pressurizing and cooling, it peels from the fixing belt.
In the image forming method of the present invention, as a second aspect, after the toner image is formed on the electrophotographic image receiving sheet and fixed by a heat roller, the image forming of the electrophotographic image receiving sheet is further performed. The surface is heated and pressed by a fixing belt and a fixing roller, cooled, and then peeled off from the fixing belt.
In the image forming methods according to the first and second aspects, the electrophotographic image-receiving sheet is heated and pressed to a temperature of 80 ° C. or higher and lower than 110 ° C. by a fixing belt and a fixing roller, By exfoliating, the polyolefin layer softens and deforms due to pressure, but it is heated and pressurized under conditions that do not generate blisters, and by cooling to a condition where the polyolefin layer solidifies, it has excellent water resistance and surface smoothness. This is preferable in that the surface of the toner image-receiving layer having high gloss is formed.
[0122]
As a transfer method, a method used in a normal electrophotographic method, for example, a direct transfer method in which a toner image formed on a developing roller is directly transferred to an image receiving material, or after primary transfer to an intermediate transfer belt or the like. There is an intermediate transfer belt system for transferring to an image receiving material. From the viewpoint of environmental stability and high image quality, an intermediate transfer belt system is preferably used.
[0123]
In the electrophotographic image receiving material of the present invention, the toner transferred onto the image receiving material is fixed on the image receiving material using an electrophotographic apparatus having a fixing belt. As the belt fixing method, for example, an oilless type belt fixing method described in JP-A-11-352819, secondary transfer and fixing described in JP-A-11-231671 and JP-A-5-341666 are used. Methods to achieve at the same time are known. The electrophotographic apparatus having a fixing belt according to the present invention can convey, for example, at least a heating and pressurizing unit capable of melting and pressurizing a toner and an image receiving material to which the toner is adhered in a state of being in contact with the toner image receiving layer. An electrophotographic apparatus having a belt-type toner fixing unit having a fixing belt and, optionally, a cooling unit that can cool a heated image receiving material while attached to the fixing belt. By using an electrophotographic image-receiving material having a toner image-receiving layer in an electrophotographic apparatus having such a fixing belt, the toner adhering to the toner image-receiving layer is finely fixed without spreading on the image-receiving material and fixing. Since the molten toner is cooled and solidified in close contact with the belt, the toner is received in the toner image receiving layer in a state where the toner is completely embedded in the toner image receiving layer. Therefore, it is possible to obtain a glossy and smooth toner image with no image level difference.
[0124]
The electrophotographic image-receiving sheet formed according to the present invention is particularly suitable for an image forming method using an oil-less belt fixing method, whereby the offset is greatly improved. However, it can be similarly used for various other image forming methods.
For example, by using the electrophotographic image receiving sheet of the present invention, a full color image can be suitably formed while improving the image quality and preventing cracks. 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 paper transport section, a latent image forming section, and a developing section disposed in the vicinity of 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 adjacent to the image receiving portion and the image receiving paper transport portion.
[0125]
Further, 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 an intermediate transfer belt of a heat assisted transfer system is preferable. Further, it is preferable to provide a cooling device for the intermediate belt after toner transfer to the electrophotographic image receiving sheet or in the latter half of the transfer. With this cooling device, the toner (toner image) is cooled below the softening temperature of the binder resin used in it or the glass transition temperature of the toner, and is efficiently transferred to the electrophotographic image-receiving sheet and can be peeled off from the intermediate belt. It becomes.
[0126]
Fixing is an important process that affects the gloss and smoothness of the final image. As the fixing method, fixing by a heat and pressure roller, belt fixing using a belt, and the like are known, but the belt fixing method is preferable from the viewpoint of the image quality such as gloss and smoothness. Regarding the belt fixing method, for example, an oilless type belt fixing method described in JP-A-11-352819, secondary transfer and fixing described in JP-A-11-231671 and JP-A-5-341666 are performed. Methods to achieve at the same time are known. Further, primary pressing with a heat roller may be performed before pressing and heating with the fixing belt and the fixing roller.
[0127]
The surface of the fixing belt may be subjected to a surface treatment of silicone, fluorine, or a combination thereof in order to prevent toner releasability or toner component offset. Further, it is preferable to provide a belt cooling device in the latter half of the fixing so that the electrophotographic image-receiving sheet is peeled off satisfactorily. The cooling temperature is preferably below the softening point of the toner binder resin and / or the polymer of the toner image-receiving layer of the electrophotographic image-receiving sheet, or below the glass transition point. On the other hand, at the initial stage of fixing, it is necessary to raise the temperature to a temperature at which the toner image receiving layer or toner of the electrophotographic image receiving sheet is sufficiently softened. Specifically, the cooling temperature is preferably 80 ° C. or lower and 30 ° C. or higher for practical use.
[0128]
Here, it is appropriate that the fixing belt used in the image forming apparatus is an endless belt formed using, for example, polyimide, electroformed nickel, aluminum, or the like as a base material.
It is preferable that a thin film made of at least one selected from the group consisting of silicone rubber, fluororubber, silicone resin, and fluororesin is formed on the surface of the fixing belt. Among them, a mode in which a fluorocarbon siloxane rubber layer having a uniform thickness is provided on the surface of the fixing belt, a silicone rubber layer having a uniform thickness is provided on the surface of the fixing belt, and the surface of the silicone rubber layer is provided. An embodiment in which a layer made of a fluorocarbon siloxane rubber is provided is preferable.
[0129]
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.
[0130]
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.
[0131]
[Chemical 1]

[0132]
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.
[0133]
Examples of the component (A) include those represented by the following formula (2).
[0134]
[Chemical formula 2]

[0135]
In the component (B), examples of the organopolysiloxane having ≡SiH groups include organohydrogenpolysiloxanes having at least two hydrogen atoms bonded to silicon atoms in the molecule.
[0136]
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.
[0137]
As such organohydrogenpolysiloxane, various organohydrogenpolysiloxanes used in addition-curable silicone rubber compositions can be used.
[0138]
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.
[0139]
Further, the fluorocarbon having an ≡SiH group may be a unit of the above formula (1) or R in the formula (1).¹⁰Is a dialkylhydrogensiloxy group and the terminal is preferably a SiH group such as a dialkylhydrogensiloxy group or a silyl group, and examples thereof include those represented by the following formula (3).
[0140]
[Chemical Formula 3]

[0141]
As the filler of 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.
[0142]
As the catalyst of 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, platinum, alumina, silica, carbon, etc. Examples include those supported on a carrier, complex of rhodium and olefin, group VIII element of periodic table such as chlorotris (triphenylphosphine) rhodium (Wilkinson catalyst), rhodium (III) acetylacetonate and the like. However, these complexes are preferably used by dissolving in a solvent such as alcohol, ether, or hydrocarbon.
[0143]
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 solvent 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.
[0144]
The fixing belt 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 hexafluoride or benzotrifluoride to form 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.
[0145]
The thickness of the fluorocarbon siloxane rubber layer formed on the surface of the fixing belt is not particularly limited. However, in order to obtain good image fixing properties by preventing toner releasability or toner component offset. 500 μm, particularly 40 to 200 μm is preferable.
[0146]
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.
[0147]
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.
[0148]
According to the image forming method of the present invention, even when an oilless machine having no fixing oil is used, it is possible to prevent the image receiving sheet and the toner from being peeled off or the image receiving sheet and the toner component from being offset, thereby realizing stable paper feeding. At the same time, it is possible to realize a good image having unprecedented good glossiness and rich in photographic feeling.
[0149]
【Example】
EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to the following Example at all.
In the following examples, “%” and “part” are based on mass.
[0150]
Example 1
-Preparation of base paper-
Hardwood bleached kraft pulp (LBKP) was beaten with a disc refiner to 300 cc (Canadian standard freeness, CFS) and adjusted to a fiber length of 0.58 mm. Additives were added to the pulp stock at the following ratio based on the mass of the pulp.
Type of additive Amount (%)
Cationic starch 1.2
Alkyl ketene dimer (AKD) 0.5
Anionic polyacrylamide 0.3
Epoxidized fatty acid amide (EFA) 0.2
Polyamide polyamine epichlorohydrin 0.3
Note) AKD means alkyl ketene dimer (the alkyl part is derived from a fatty acid mainly composed of behenic acid), and EFA is an epoxidized fatty acid amide (the fatty acid part is derived from a fatty acid mainly composed of behenic acid). Is).
[0151]
The obtained pulp paper stock was basis weight 150 g / m by a long net paper machine.²A base paper was prepared. In addition, PVA 1.0 g / m by a size press machine in the middle of the drying zone of the long paper machine.², CaCl₂  0.8g / m²Attached.
At the end of the papermaking process, using a soft calendar, the density is 1.01 g / cm³Adjusted. In the obtained base paper, the metal roll was passed through on the side where the toner image-receiving layer was provided, and the surface temperature of the metal roll was 140 ° C. The resulting base paper had a whiteness of 91%, an Oken-type smoothness of 265 seconds, and a Steecht size of 127 seconds.
[0152]
After the obtained base paper was treated by corona discharge with an output of 17 kW, a cooling roll having a surface mat roughness of 10 μm was used on the back surface, and a polyethylene resin having the composition shown in Table 1 was melted at a film discharge temperature of 320 ° C. and a line speed of 250 m A single layer extrusion lamination was performed at a rate of / min, and a polyethylene resin layer having a thickness of 22 μm was provided.
[0153]
[Table 1]

[0154]
Next, using a cooling roll having a surface mat roughness of 0.7 μm on the surface of the base paper on which the toner image-receiving layer is coated, polyethylene resin, titanium oxide masterbatched as shown in Table 2, 5 mass % LDPE masterbatch-gun blue mixed in a single layer extrusion lamination at a melt discharge film temperature of 320 ° C. and a line speed of 250 m / min. A polyethylene resin layer having a thickness of 29 μm was provided.
Then, after processing by corona discharge with an output of 18 kW on the front surface and an output of 12 kW on the back surface, a gelatin undercoat layer is provided on the front surface, and an antistatic undercoat layer containing colloidal alumina, colloidal silica, and PVA is provided on the back surface. The body was made.
[0155]
[Table 2]

[0156]
[Table 3]

[0157]
Next, a self-dispersing polyester resin aqueous dispersion, carnauba wax aqueous dispersion, titanium dioxide PVA dispersion and polyethylene oxide having a molecular weight of about 100,000 are finally formed on the front surface of the support. The electrophotographic image-receiving sheet of Example 1 was prepared by providing a toner image-receiving layer with a bar coater so that the coating amount composition shown in FIG. The coating solution had a viscosity of 70 mPa · s, a surface tension of 30 mN / m, and a pH of 7.8.
The obtained electrophotographic image-receiving sheet of Example 1 had a whiteness of 87 and an opacity of 93.
[0158]
[Table 4]

[0159]
(Comparative Example 1)
In the same manner as in Example 1, a base paper, a support, and an electrophotographic image receiving sheet were prepared. However, the composition of the toner image-receiving layer was changed as shown in Table 5.
[0160]
[Table 5]

[0161]
(Comparative Example 2)
In the same manner as in Example 1, a base paper, a support, and an electrophotographic image receiving sheet were prepared. However, the composition of the toner image-receiving layer was changed as shown in Table 6.
[0162]
[Table 6]

[0163]
Next, the obtained electrophotographic image-receiving sheets of Example 1 and Comparative Examples 1 and 2 were cut into A6 size and white, gray, black using Fuji Xerox Co., Ltd. color electrophotographic printer DocuCenterColor400. Yellow, magenta, cyan, blue, green, and red color images were printed. However, in Comparative Example 2, about 5 sheets were printed, and 4 sheets did not pass through the fixing portion.
[0164]
The printed image was subjected to post-gloss processing using the belt fixing device 1 shown in FIG. However, the conveying speed of the belt 2 was set to 60 mm / second, and the set temperatures of the heating roller 3 and the pressure roller 4 were set to 130 ° C. In FIG. 1, 6 is a cooling device.
Immediately after printing and post-processing, the 20-degree glossiness of a white background was measured based on JIS Z8741. Then, it was left to stand at 28 ° C. in an 85% RH environment for 1 week and 2 weeks. Table 7 shows the results of measuring the glossiness over time.
Further, the blocking resistance is 50 / cm by superimposing the black portion and the back surface of the toner image receiving surface.²Evaluation was performed according to the following criteria by leaving it in an oven at 40 ° C. for 48 hours under a load of The results are shown in Table 7.
<Evaluation criteria>
A: Adhesion was not observed.
○: Adhesion was observed, but could be easily peeled off, and no adhesion mark was observed.
(Triangle | delta): Although adhesion | attachment was seen, it was able to peel off easily. However, adhesion marks can be seen.
X: There was adhesion, and when peeled off, the screen was missing.
[0165]
[Table 7]

In Table 7, the x marks indicate that cracks occurred and the glossiness was not measurable.
In Example 1, the same result was obtained even when the carnauba wax was changed to polyethylene wax.
[0166]
(Example 2)
A self-dispersing acrylic resin aqueous dispersion was used on the front surface of the support prepared in Example 1, and finally the coating amount composition shown in Table 8 was used. Provided. After drying, a self-dispersing polyester resin aqueous dispersion, a carnauba wax aqueous dispersion, a titanium dioxide PVA dispersion and a polyethylene oxide having a molecular weight of about 100,000 are finally formed on the undercoat layer. An electrophotographic image-receiving sheet of Example 2 having a toner image-receiving layer having a multilayer structure was prepared by providing a toner image-receiving layer with a bar coater so as to have a coating amount composition.
[0167]
[Table 8]

[0168]
[Table 9]

[0169]
(Examples 3 to 5)
In the same manner as in Example 2, a base paper, a support, and an electrophotographic image receiving sheet were prepared. However, the amounts of carnauba wax and polyethylene oxide in the toner image-receiving layer and the undercoat layer were changed as shown in Table 10.
[0170]
The obtained electrophotographic image-receiving sheets of Examples 2 to 5 were subjected to post-glossing using the belt fixing device 1 shown in FIG. Thereafter, the 20-degree glossiness and blocking resistance of the white background were evaluated in the same manner as in Example 1. The results are shown in Table 10.
[0171]
[Table 10]

In Examples 2 to 5, similar results were obtained even when the carnauba wax was changed to polyethylene wax.
[0172]
【The invention's effect】
As described above, according to the present invention, in particular, oilless fixing is possible, and even when left in a high-humidity environment, there is little decrease in glossiness of a white background portion, and high resistance to blocking and brittleness is high. A high-quality electrophotographic image-receiving sheet can be obtained.
[Brief description of the drawings]
FIG. 1 is a schematic diagram illustrating an example of a belt fixing device used in an embodiment.
[Explanation of symbols]
1 Belt fixing device
2 belts
3 Heating roller
4 Pressure roller
5 Tension roller
6 Cooling device

Claims (10)

The support has at least one toner image-receiving layer, and the toner image-receiving layer contains carnauba wax and polyethylene oxide which is a water-soluble polymer having a nonionic polar group, and the carnauba wax and the polyethylene An electrophotographic image-receiving sheet, wherein a mixing mass ratio with respect to oxide (carnauba wax: polyethylene oxide) is 1: 0.1 to 10. It has a toner image-receiving layer having a laminated structure of two or more layers on the support, contains carnauba wax in the outermost surface layer of the toner image-receiving layer, and has nonionic polar groups in layers other than the outermost surface layer. An electrophotographic image-receiving sheet comprising polyethylene oxide which is a water-soluble polymer. A toner image-receiving layer having a laminated structure of two or more layers is provided on a support, and carnauba wax is included in the outermost surface layer of the toner image-receiving layer, and layers other than the outermost surface layer and the outermost surface layer of the toner image-receiving layer An electrophotographic image-receiving sheet comprising: polyethylene oxide which is a water-soluble polymer having a nonionic polar group. 4. The electrophotographic image receiving image according to claim 2, wherein the total mass ratio of carnauba wax to polyethylene oxide (carnauba wax: polyethylene oxide) in the toner image-receiving layer having two or more layers is 1: 0.1 to 10. 5. Sheet. 5. The electrophotographic image-receiving sheet according to claim 1, wherein the polyethylene oxide has an average molecular weight of 10,000 or more. 6. An image forming method using the electrophotographic image-receiving sheet according to claim 1, wherein a toner image is formed on the electrophotographic image-receiving sheet, and then the image of the electrophotographic image-receiving sheet. An image forming method, wherein a forming surface is heated and pressed by a fixing belt and a fixing roller, cooled, and then peeled off from the fixing belt. An image forming method using the electrophotographic image-receiving sheet according to any one of claims 1 to 5, wherein after forming a toner image on the electrophotographic image-receiving sheet and fixing with a heat roller, An image forming method, wherein the image forming surface of the electrophotographic image receiving sheet is heated and pressed by a fixing belt and a fixing roller, cooled, and then peeled off from the fixing belt. The image forming method according to claim 6 or 7, wherein a layer made of a fluorocarbon siloxane rubber having a uniform thickness is provided on the surface of the fixing belt. 8. The image forming method according to claim 6, further comprising a silicone rubber layer having a uniform thickness on the surface of the fixing belt, and a fluorocarbon siloxane rubber layer provided on the surface of the silicone rubber layer. The image forming method according to claim 8 or 9, wherein the fluorocarbon siloxane rubber has a perfluoroalkyl ether group and / or a perfluoroalkyl group in a main chain.

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