JP3573870B2 - Photo material - Google Patents

Description

【００４４】
数１において、Ｗｘは試料面域のＸ軸方向（抄紙方向）の長さを表わし、Ｗｙは試料面域のＹ軸方向（抄紙方向と垂直な方向）の長さを表わし、Ｓａは試料面域の面積を表わす。
【００４５】
本発明の実施に好ましく用いられる、中心面平均粗さＳＲａが１．４５μｍ以下の基紙を製造する方法としては、具体的には、平滑性の出やすいサルファイトパルプ、好ましくは広葉樹サルファイトパルプを３０重量％以上、好ましくは５０重量％以上用い、湿紙の乾燥途中で多段の緊度プレスを行い、更に基紙を抄造後マシンカレンダー、スーパーカレンダー、熱カレンダー等を用いて少なくとも２系列以上のカレンダー処理、例えば基紙に第１系列のカレンダー処理としてマシンカレンダー処理あるいは／及び熱マシンカレンダー処理を行い、その後第２系列以降のカレンダー処理として必要に応じて更にマシンカレンダー処理を行った後特開平４−１１０９３９号公報に記載もしくは例示の熱ソフトカレンダー処理を行って、中心面平均粗さＳＲａが１．４５μｍ以下の基紙を製造することが出来る。また、基紙中あるいは基紙上に各種の水溶性ポリマーもしくは親水性コロイドあるいはポリマーラテックスをサイズプレスもしくはタブサイズプレスあるいはブレード塗工、エアーナイフ塗工などの塗工によって固形塗布量として１．０ｇ／ｍ^２以上、特に２．２ｇ／ｍ^２以上含有あるいは塗設せしめるのが好ましい。
【００４６】
本発明による写真材料としては、本発明における写真材料用支持体上に各種の写真構成層が設けられたものであり、カラー写真印画紙用、白黒写真印画紙用、反転写真材料用、銀塩拡散転写法ネガ用及びポジ用、色素拡散転写法用等各種のものを包含する。例えば、塩化銀、臭化銀、塩臭化銀、沃臭化銀、塩沃臭化銀乳剤層を設けたものを包含する。ハロゲン化銀写真乳剤層にカラーカプラーを含有せしめたハロゲン化銀カラー写真材料を包含する。また、銀塩拡散転写法用写真構成層を設けたものを包含する。本発明による特に有用な写真材料は、写真材料用支持体上に下引層、イエローカプラーを含む青感ハロゲン化銀写真乳剤層と中間層、マゼンタカプラーを含む緑感ハロゲン化銀写真乳剤層と紫外線吸収層、シアンカプラーを含む赤感ハロゲン化銀写真乳剤層と保護層等のハロゲン化銀カラー写真構成層が順に設けられて多層配置にされた多層ハロゲン化銀カラー写真材料である。それらの写真構成層の結合剤としては、通常のゼラチンの他に、ポリビニルピロリドン、ポリビニルアルコール、多糖類の硫酸エステル化合物等の親水性高分子物質を用いることができる。また、上記の写真構成層には各種の添加剤を含有せしめることができる。例えば、増感色素として、シアニン色素、メロシアニン色素等、化学増感剤として、水溶性金化合物、イオウ化合物等、カブリ防止剤もしくは安定剤として、ヒドロキシ−トリアゾロピリミジン化合物、メルカプト−複素環化合物等、汚染防止剤として、ジアルキルハイドロキノン化合物等、そのほか蛍光増白剤、鮮鋭度向上色素、帯電防止剤、ｐＨ調製剤、カブらせ剤、さらにハロゲン化銀の生成・分散時に水溶性イリジウム、水溶性ロジウム化合物等を適宜組み合わせて含有せしめることができる。
【００４７】
本発明による写真材料の写真構成層中には、各種の塗布助剤を含有せしめるのが好ましい。それらの塗布助剤としては、特開昭６２−３０２４６号公報、特開昭６２−４４７３４号公報に記載もしくは例示のアルキルベンゼンスルフォン酸塩、スルフォコハク酸エステル塩などのアニオン系界面活性剤、特開平１−１６６０３５号公報に記載もしくは例示のスルフォベタイン型界面活性剤、サニポン、アルキルオキサイド系等のノニオン系界面活性剤、特開昭４７−９３０３号公報、米国特許 ３，５８９，９０６号明細書等に記載もしくは例示のフルオロ化した界面活性剤等の各種の塗布助剤を単独にあるいは併用して含有せしめるのが好ましい。
【００４８】
また、本発明による写真材料の写真構成層中には、各種の硬膜剤を含有せしめるのが好ましい。それらの硬膜剤としては、特開昭６２−３０２４４号公報、特開昭６２−３０２４５号公報に記載もしくは例示の活性ハロゲン化合物、ビニルスルフォン化合物、アジリジン化合物、エポキシ化合物、アクリロイル化合物、イソシアネート化合物、アルボジイミド化合物、イソオキサゾール化合物などの各種の硬膜剤を単独にあるいは併用して含有せしめるのが好ましい。また、硬膜剤の含有量としては、写真構成層中の主ポリマーであるゼラチンの種類、写真材料の種類、現像処理条件などにより異なるが、概ね写真構成層用の塗布液中のゼラチンに対して、ゼラチンの乾燥重量基準で０．０５重量％〜１０重量％、好ましくは０．１重量％〜５重量％の範囲である。又、硬膜剤の添加時期としては、塗布液を調整する任意の段階でよいが、特にハロゲン化銀乳剤に添加する場合には、一般にハロゲン化銀乳剤の化学熟成（第２熟成）後に添加するのが良い。更に、写真構成層の各層への硬膜剤の添加配合としては、ハロゲン化銀写真乳剤層には少なく、非感光性層には多く添加するとか、また支持体より遠い写真構成層には多く、支持体に近い写真構成層には少なく添加するなど各種の添加配合を採用するのが好ましい。
【００４９】
本発明の実施に当たり、下引層を有する写真材料用支持体に写真構成層用塗布液を塗設する方法としては、多層ハロゲン化銀カラー写真印画紙を製造するに適した塗布方法を選択するのが好ましい。代表的な塗布方法としては、多層スライドホッパーより多層写真構成層用塗布液を流下せしめ、多層ビードを形成しつつ多層写真構成層用塗布液を同時に支持体に塗設する多層スライドホッパー方式、いわゆるＥバーコート方式で塗布することが出来る。もう１つの代表的な塗布方法としては、多層スライドホッパーより多層写真構成層用塗布液を流下せしめ、重力場にてカーテンを形成しつつ、好ましくはカーテンの両端をガイドにて安定させつつ、かつ減圧下でカーテンのゆれをなくしつつ多層写真構成層用塗布液を同時に支持体に塗設する方式、いわゆるカーテンコート方式で塗布するのが好ましい。また、塗布速度としては、写真材料の生産性の点から、１５０ｍ／分以上、好ましくは２００ｍ／分以上、特に好ましくは３００ｍ／分以上である。
【００５０】
本発明に係る写真材料は、その写真材料に合わせて「写真感光材料と取扱法」（共立出版、宮本五郎著、写真技術講座２）に記載されている様な露光、現像、停止、定着、漂白、安定などの処理を行うことが出来る。また、多層ハロゲン化銀カラー写真材料は、ベンジルアルコール、タリウム塩、フェニドンなどの現像促進剤を含む現像液で処理してもよいし、ベンジルアルコールを実質的に含まない現像液で処理することもできる。
【００５１】
【実施例】
次に、本発明を更に具体的に説明するために、実施例を述べる。
【００５２】
実施例１
広葉樹漂白クラフトパルプ３０重量％及び広葉樹漂白サルファイトパルプ７０重量％から成る混合パルプを叩解後のパルプの繊維長（ＪＡＰＡＮ ＴＡＰＰＩ紙パルプ試験方法Ｎｏ，５２−８９「紙及びパルプ繊維長試験方法」に準拠して測定した長さ加重平均繊維長で表示して）が０．５８ｍｍになるように叩解後、パルプ１００重量部に対して、カチオン化澱粉３重量部、アニオン化ポリアクリルアミド０．２重量部、アルキルケテンダイマー乳化物（ケテンダイマー分として）０．４重量部、ポリアミドエピクロルヒドリン樹脂０．４重量部及び適当量の蛍光増白剤、青色染料、赤色染料を添加して紙料スラリーを調製した。その後、紙料スラリーを２００ｍ／分で走行している長網抄紙機にのせ、適切なタービュレンスを与えつつ紙匹を形成し、ウェットパートで１５ｋｇ／ｃｍ〜１００ｋｇ／ｃｍの範囲で線圧が調節された３段のウェットプレスを行った後、スムージングロールで処理し、引き続く乾燥パートで３０ｋｇ／ｃｍ〜７０ｋｇ／ｃｍの範囲で線圧が調節された２段の緊度プレスを行った後、乾燥した。その後、乾燥の途中でカルボキシ変性ポリビニルアルコール４重量部、蛍光増白剤０．０５重量部、青色染料０．００２重量部、塩化ナトリウム４重量部及び水９２重量部から成るサイズプレス液を２５ｇ／ｍ^２サイズプレスし、最終的に得られる基紙水分がマイクロ波水分計で８重量％になるように乾燥し、線圧７０ｋｇ／ｃｍでマシンカレンダー処理して、坪量１７０ｇ／ｍ^２の膜厚むら指数Ｒｐｙが１３０ｍＶ、かつ中心面平均粗さＳＲａが１．２０μｍである基紙を製造した。
【００５３】
次に、写真構成層を設ける側とは反対側の基紙面（裏面）をコロナ放電処理した後、該裏面に下記の樹脂組成物（Ｒ１）または（Ｒ２）を樹脂温度３１５℃で２３μｍの樹脂厚さに基紙の走行速度２００ｍ／分で溶融押し出しコーティングした。この際、冷却ロールとしては、下記バック層を塗設後の該バック層面の中心面平均粗さ（ＳＲａ）の自乗値が０．７５μｍ^２になるように冷却ロールは液体ホーニング法で粗面化された冷却ロールを用い、冷却水温度１２℃で操業した。
【００５４】
（樹脂組成物Ｒ１）高密度ポリエチレン樹脂（密度０．９６７ｇ／ｃｍ^３、ＭＦＲ＝６．５ｇ／１０分）５０重量部と低密度ポリエチレン樹脂（密度０．９２６ｇ／ｃｍ^３、ＭＦＲ＝３．５ｇ／１０分）５０重量部と単純混合した樹脂組成物であって、単純混合のまま溶融押し出し機に添加して使用した。
【００５５】
（樹脂組成物Ｒ２）高密度ポリエチレン樹脂（密度０．９６７ｇ／ｃｍ^３、ＭＦＲ＝１５ｇ／１０分）７０重量部と低密度ポリエチレン樹脂（密度０．９２４ｇ／ｃｍ^３、ＭＦＲ＝０．６ｇ／１０分）３０重量部とを溶融押し出し機を用いて予め溶融・混合して調製したコンパウンド樹脂組成物であり、そのペレットとして使用した。
【００５６】
引き続き、基紙の表面をコロナ放電処理した後、該表面に低密度ポリエチレン樹脂（密度０．９２０ｇ／ｃｍ^３、ＭＦＲ＝８．５ｇ／１０分）４７．５重量％、含水酸化アルミニウム（対二酸化チタンに対してＡｌ_２Ｏ_３分として０．７５重量％）で表面処理したアナターゼ型二酸化チタン顔料５０重量％とステアリン酸亜鉛２．５重量％から成る二酸化チタン顔料のマスターバッチ２０重量部、低密度ポリエチレン樹脂（密度０．９２０ｇ／ｃｍ^３、ＭＦＲ＝４．５ｇ／１０分）６５重量部と高密度ポリエチレン樹脂（密度０．９７０ｇ／ｃｍ^３、ＭＦＲ＝７．０ｇ／１０分）１５重量部から成る樹脂組成物を樹脂温度３１５℃で３０μｍの厚さに基紙の走行速度２００ｍ／分で溶融押し出しコーティングした。なお、表、裏のポリエチレン樹脂の溶融押し出しコーティングは、逐次押し出しコーティングが行われる、いわゆるタンデム方式で行われた。その際、該樹脂被覆紙の二酸化チタン顔料を含む樹脂層の表面はグロッシー面に加工した。
【００５７】
更に、表、裏樹脂層を加工後巻き取るまでの間に、樹脂被覆紙の裏樹脂層面にコロナ放電処理後、下記のバック層用塗液をオンマシン塗布した。乾燥重量分として、コロイド状シリカ：スチレン系ラテックス＝１：１から成り、更にポリスチレンスルフォン酸ソーダ０．０２１ｇ／ｍ^２の他適量の塗布助剤等を含むバック層用塗液をラテックス分（固形重量計算で）として０．２１ｇ／ｍ^２になる塗布量で塗設した。なお、別途裏樹脂層の赤外二色比を測定するために、バック層を設けない試料も作成した。
【００５８】
さらに、バック層を塗設後、樹脂被覆紙を巻き取るまでの間に、表側の樹脂面にコロナ放電処理を施し、石灰処理ゼラチン１．２ｇ、低分子量ゼラチン（新田ゼラチン株式会社製、Ｐ−３２２６）０．３ｇ、パラオキシ安息香酸ブチルの１０重量％メタノール溶液０．３ｇ及びスルフォコハク酸−２−エチルヘキシルエステル塩のメタノールと水の５重量％混合液０．４５ｇを含み、全量を水で１００ｇに調製した配合の下引層用塗液をゼラチン塗布量０．０６ｇ／ｍ^２になるように均一にオンマシン塗布して写真材料用支持体を得た。
【００５９】
次いで、グリット制御イオン化装置タイプの極性電荷発生装置により、写真材料用支持体の下引層面に表１に記載の電位を附与した後該下引層上に黄色発色カプラーを含む青感乳剤層、色混り防止剤を含む中間層、マゼンタ発色カプラーを含む緑感乳剤層、紫外線吸収剤を含む紫外線吸収層、シアン発色カプラーを含む赤感乳剤層及び保護層のための各塗液を多層スライドポッパーより流下させてカーテンを形成しつつカーテンコート方式により塗設してゼラチンの総量（乾燥重量）が８ｇ／ｍ^２であるカラー印画紙を作成した。各色感乳剤層は硝酸銀で０．６ｇ／ｍ^２に相当する塩臭化銀を含み、更にハロゲン化銀の生成、分散及び成膜に必要なゼラチンの他、適量のカブリ防止剤、増感色素、塗布助剤、硬膜剤、増粘剤及び適量のフィルター染料等を含む。なお、各塗布液の粘度は、２５センチポイズ〜１００センチポイズの間にあり（青感乳剤層用塗液の粘度は２５センチポイズ）、カーテン高さは１２ｃｍ、塗布速度は２１０ｍ／分であった。また、ゼラチン総量８ｇ／ｍ^２に対して、化１で示される硬膜剤の総量で０．０６ｇ／ｍ^２になる量を適宜各塗布液に配分して含有せしめた。
【００６０】
【化１】

【００６１】
次に、作成したカラー印画紙を３５℃、常湿で４日間加温した後、カラー印画紙のハロゲン化銀カラー写真構成層の硬膜度の評価を行った。ハロゲン化銀カラー写真構成層の硬膜度の評価方法としては、カラー発色現像液で３３℃、３分３０秒間現像後、球直径１ｍｍのボールポイント針をハロゲン化銀カラー写真構成層の膜面に垂直に立て、試料面を２ｃｍ／ｓｅｃの速さで移動させた時の膜面に損傷を生じるボールポイント針の荷重（以降膜強度とする）を測定し、膜強度を評価した。
【００６２】
得られた結果を表１に示す。
【００６３】
【表１】

【００６４】
なお、表１中の（注１）〜（注２）は、以下の通りである。
【００６５】
（注１）○は本発明による試料を示す。
【００６６】
（注２）バック層を設けていない試料につき、明細書本文中に記載された方法で測定された裏樹脂層の赤外二色比を示す。
【００６７】
表１の結果から、ポリエチレン樹脂を含む、赤外二色比が０．５５〜０．８５である裏樹脂層で基紙が被覆された樹脂被覆紙型写真材料用支持体の下引層面にプラス１００ボルト以上の電位を附与した後ハロゲン化銀カラー写真構成層が設けられた本発明における写真材料（試料Ｎｏ．８〜Ｎｏ．１２）は、それらの相乗効果により、硬膜がよく効いた優れた写真材料であることがよくわかる。また、附与する電位としては、写真材料の硬膜の改良効果の点から、プラス２５０ボルト以上が好ましく、プラス５００ボルト以上が更に好ましく、プラス７５０ボルト以上が特に好ましいことがよくわかる。
【００６８】
一方、ポリエチレン系樹脂を含む裏樹脂層として、その赤外二色比が、０．８５より大きいものを用いた場合（試料Ｎｏ．１〜Ｎｏ．６）、下引層に附与する電位がプラス１００ボルト未満である場合（試料Ｎｏ．７）、下引層に附与する電位がマイナスである場合（試料Ｎｏ．１３）の本発明外の写真材料は、その硬膜が弱くて問題であることがよくわかる。
【００６９】
実施例２
実施例１の試料Ｎｏ．１０で用いた樹脂組成物（Ｒ２）の代わりに、下記の樹脂組成物（Ｒ１）〜（Ｒ６）を用いる以外は実施例１の試料Ｎｏ．１０と同様に実施した。
【００７０】
（樹脂組成物Ｒ１）実施例１で用いた樹脂組成物（Ｒ１）と同一のもの。
（樹脂組成物Ｒ２）実施例１で用いた樹脂組成物（Ｒ２）と同一のもの。
【００７１】
（樹脂組成物Ｒ３）高密度ポリエチレン樹脂（密度０．９６７ｇ／ｃｍ^３、ＭＦＲ＝６．８ｇ／１０分）６５重量部と低密度ポリエチレン樹脂（密度０．９２６ｇ／ｃｍ^３、ＭＦＲ＝３．５ｇ／１０分）３５重量部とを単純混合した樹脂組成物であって、単純混合のまま溶融押し出し機に添加して使用した。
【００７２】
（樹脂組成物Ｒ４）高密度ポリエチレン樹脂（密度０．９６７ｇ／ｃｍ^３、ＭＦＲ＝１０ｇ／１０分）６５重量部と低密度ポリエチレン樹脂（密度０．９２６ｇ／ｃｍ^３、ＭＦＲ＝０．６ｇ／１０分）３５重量部とを溶融押し出し機を用いて予め溶融・混合して調製したコンパウンド樹脂組成物であり、そのペレットとして使用した。
【００７３】
（樹脂組成物Ｒ５）高密度ポリエチレン樹脂（密度０．９６７ｇ／ｃｍ^３、ＭＦＲ＝１０ｇ／１０分）７８重量部と低密度ポリエチレン樹脂（密度０．９２６ｇ／ｃｍ^３、ＭＦＲ＝０．６ｇ／１０分）２２重量部とを溶融押し出し機を用いて予め溶融・混合して調製したコンパウンド樹脂組成物であり、そのペレットとして使用した。
【００７４】
（樹脂組成物Ｒ６）高密度ポリエチレン樹脂（密度０．９６７ｇ／ｃｍ^３、ＭＦＲ＝１５ｇ／１０分）８５重量部と低密度ポリエチレン樹脂（密度０．９２６ｇ／ｃｍ^３、ＭＦＲ＝０．６ｇ／１０分）１５重量部とを溶融押し出し機を用いて予め溶融・混合して調製したコンパウンド樹脂組成物であり、そのペレットとして使用した。
【００７５】
得られた結果を表２に示す。
【００７６】
【表２】

【００７７】
なお、表２中の（注１）〜（注２）は、表１中のそれらと同意義である。
【００７８】
表２の結果から、裏樹脂層の赤外二色比が０．５５〜０．８５である本発明における写真材料（試料Ｎｏ．１５〜Ｎｏ．１８）は、ハロゲン化銀写真構成層の硬膜がよく効いた優れた写真材料であることがよくわかる。また、硬膜の改良効果及び樹脂組成物の成形加工性等の総合性能の点から、裏樹脂層の赤外二色比が０．７５以下である写真材料が好ましく、０．６５以下かつ０．５５以上である写真材料が特に好ましいことがよくわかる。一方、本発明外の写真材料（Ｎｏ．１４及びＮｏ．１９）は写真材料の硬膜が弱かったり、成形加工性等が不十分であったりして、問題があることがよくわかる。
【００７９】
実施例３
実施例１の試料Ｎｏ．１０で用いた樹脂厚さ２３μｍの裏樹脂層の代わりに、表３に記載の樹脂厚さの裏樹脂層を用いる以外は、実施例１の試料Ｎｏ．１０と同様に実施した。なお、裏樹脂層の赤外二色比は、各々０．６３であった。
【００８０】
得られた結果を表３に示す。
【００８１】
【表３】

【００８２】
なお、表３中の（注１）は、表１中のそれと同意義である。
【００８３】
表３の結果から、樹脂被覆紙型写真材料用支持体の裏樹脂層の厚さが厚くなると写真材料の写真構成層の硬膜が強くなることがわかる。このことは、裏樹脂層が、表樹脂層に塗設された写真構成層の硬膜に影響を与えるという本発明の特異な相乗効果を示している。又、裏樹脂層の厚さは、２０μｍ〜３４μｍの範囲が好ましいことが理解出来る。裏樹脂層の厚さが３４μｍより厚いと写真材料のカール物性等が悪くなって問題となる。
【００８４】
実施例４
実施例３の試料Ｎｏ．２３において用いた基紙の代わりに、マイクロ波水分計で測定して表１に記載の水分含有率である基紙を用いる以外は、実施例３の試料Ｎｏ．２３と同様に実施した。なお、裏樹脂層の赤外二色比は、０．６３であった。
【００８５】
得られた結果を表４に示す。
【００８６】
【表４】

【００８７】
なお、表４中の（注１）は、表１中のそれと同意義である。
【００８８】
表４の結果から、本発明の実施に用いられる樹脂被覆紙用基紙としては、写真材料の硬膜の改良効果の点から、マイクロ波水分計で測定して水分含有率が７．５重量％以上であり、かつ９．５重量％未満である基紙が好ましいことがよくわかる。
【００８９】
実施例５
実施例１において写真構成層用塗液をカーテンコート方式で塗設する代わりに、Ｅバーコート方式で塗設し、青感乳剤層用塗液として６センチポイズのものを用いる以外は実施例１と同様に実施し、実施例１と同様な結果を得た。
【００９０】
実施例６
実施例１で用いた化１で示される硬膜剤の代わりに、化２で示される硬膜剤を９６ｍｇ／ｍ^２用いる以外は実施例１と同様に実施して、実施例１と同様の結果を得た。
【００９１】
【化２】

【００９２】
【発明の効果】
本発明により、写真構成層の膜物性が良好であり硬膜がよく効いた、樹脂被覆紙を支持体とする優れた写真材料を提供出来る。[0001]
TECHNICAL FIELD OF THE INVENTION
In the present invention, a paper substrate (hereinafter, sometimes referred to as a base paper) on the side on which one of the photographic constituent layers is provided is a resin layer (A) containing a polyolefin resin, using paper mainly composed of natural pulp as a substrate. The present invention relates to a photographic material in which a photographic constituent layer is provided via a subbing layer on a resin-coated paper-type photographic material support coated and covered with a resin layer (B) containing a polyethylene resin on the opposite side of the paper substrate. More specifically, the present invention relates to a photographic material having an excellent hardened film having good film physical properties of a photographic constituent layer.
[0002]
[Prior art]
Usually, a photographic material is composed of a support for a photographic material and a photographic component layer provided on the support. Such a photographic constituent layer includes a silver halide photographic emulsion layer, a protective layer, an undercoat layer, an intermediate layer or an anti-color mixing layer, an antihalation layer, or a filter layer, an ultraviolet absorbing layer, a back layer, and the like, and combinations thereof. It is composed. For example, a single silver halide photographic material has a silver halide photographic emulsion layer and a protective layer provided on a photographic material support. Further, a multilayer silver halide color photographic material comprises an undercoat layer, a blue-sensitive silver halide photographic emulsion layer and an intermediate layer, a green-sensitive silver halide photographic emulsion layer and an ultraviolet absorbing layer, A silver halide photographic emulsion layer and a silver halide color photographic constituting layer such as a protective layer are provided in order and are arranged in a multilayer.
[0003]
BACKGROUND ART Conventionally, a resin-coated paper-type support in which a base paper surface for a photographic material support is coated with a thermoplastic resin layer is well known. For example, Japanese Patent Publication No. 55-12584 discloses a technique for a photographic material support in which a base paper is coated with a film-forming resin, preferably a polyolefin resin. U.S. Pat. No. 3,501,298 discloses a technique for a photographic material support in which both sides of a base paper are coated with a polyolefin resin. Since the rapid photographic processing of silver halide photographic materials was applied, supports for photographic materials in which both sides of the base paper were coated with a polyethylene resin have been mainly used for photographic printing paper. If necessary, the resin layer on the side on which one image forming layer is provided usually contains a titanium dioxide pigment in order to impart sharpness.
[0004]
Further, a resin-coated paper provided with an undercoat layer for the purpose of improving the coating property of the photographic constituent layer coating solution on the support for photographic materials or for providing good adhesion between the support and the photographic constituent layer. Supports for photographic materials are known. JP-A-50-97325 and JP-A-61-84643 disclose a support for a resin-coated paper type photographic material provided with an undercoat layer containing gelatin as a main component. JP-A-59-142543, JP-A-59-226344, JP-A-61-107343, JP-A-62-260149 and the like mainly disclose gelatin containing various preservatives. A support for a resin-coated paper type photographic material provided with an undercoat layer as a component is disclosed. JP-A-62-30246, JP-A-62-44735, JP-A-1-92740, JP-A-1-16635 and the like disclose gelatin containing various surfactants as a main component. A resin-coated paper type photographic material support provided with an undercoat layer is disclosed. Further, JP-A-62-30244 and JP-A-62-30245 disclose resin-coated paper type photographic materials provided with an undercoat layer containing gelatin as a main component and containing various hardeners. A support is disclosed.
[0005]
There are also several technical proposals for coating a photographic component layer on a photographic material support having an undercoat layer. JP-A-2-24647 discloses a photographic emulsion called mottle by applying a high-frequency corona treatment to a resin-coated paper type photographic support material having an adhesion layer mainly composed of gelatin and then applying a photographic emulsion. A method for producing a photographic support material capable of providing a photographic material having improved coating unevenness and a technique of the photographic material are disclosed. Japanese Patent Application Laid-Open No. 63-4881 discloses that an application of an electrostatic field is applied to a web provided with a gelatin subbing layer containing a surfactant to apply a coating solution from a coating die, thereby increasing the coating speed. The technique of the coating method is disclosed.
[0006]
However, a support for a photographic material in which the side on which a photographic component layer of a base paper, particularly a base paper mainly composed of natural pulp is provided, is coated with a resin layer containing a polyolefin resin, and the opposite side is coated with a resin layer containing a polyethylene resin. A photographic material in which a photographic constituent layer is applied on a body by a conventionally known method via an undercoat layer still has a serious problem, and a satisfactory result has not yet been obtained. is there.
[0007]
Generally, a photographic material is exposed, exposed, developed, stopped, and fixed, then washed with water and dried. In particular, in the case of silver halide color photographic printing paper, development, bleaching / fixing treatment is performed after exposure, and, if necessary, after stable and washing treatment, drying and cutting. In a recent rapid photographic development processing system, a series of photographic development processing is achieved in an extremely short time of 30 to 60 seconds by an automatic processing machine. Incidentally, the photographic constituent layer is generally composed of a so-called gelatin layer mainly composed of gelatin. However, since the gelatin layer has a very good swelling property with respect to water, particularly an aqueous alkali solution, the photographic constituent layer becomes lumpy during the development processing as it is, and the development processing cannot be performed.
[0008]
For this reason, a compound called a hardener, which causes a cross-linking reaction with a functional group such as an amino group, a carboxyl group, or an amide group in the gelatin molecule, is contained in the gelatin layer to improve the physical properties of the gelatin layer. Hardening of a so-called photographic constituent layer is performed. Hardeners for this purpose include epoxy hardeners, ethyleneimino hardeners, active halogen hardeners, acryloyl hardeners, vinylsulfone hardeners, carbodiimide hardeners, etc. Many hardeners are known. However, when hardening a gelatin layer, it is necessary to obtain a sufficient hardening level at the earliest possible stage after the photographic material is manufactured, but these ordinary hardeners require a large amount of hardening. In general, the amount used is generally limited due to the extremely bad side effects involved. If the photographic constituent layers of the photographic material are insufficiently hardened, the photographic constituent layers may become excessively expanded, causing the photographic material to dry during the development process, especially during rapid photographic development, especially during the drying process. Is insufficient, and the prints after development process stick to each other, causing the so-called blocking phenomenon, or because the physical strength of the photographic component layer film is insufficient, Often, this is a serious problem in practical use, such as scratching and eventually scratching the print. The problem of insufficient hardening of the photographic constituent layer of the photographic material is that the paper base on which one of the photographic constituent layers is provided is a resin layer containing a polyolefin resin (A). This is particularly noticeable in a photographic material in which a photographic component layer is provided via a subbing layer on a resin-coated paper type photographic material support coated with a polyethylene resin (B) and a paper substrate on the opposite side is coated with a polyethylene resin (B). There was a problem of becoming.
[0009]
Therefore, the present inventors have conducted various studies on the factors of insufficient hardening of a photographic material in which a photographic constituent layer is provided on a resin-coated paper-type photographic material support via an undercoat layer, and as a result, There are various factors such as a resin-coated paper as a support, an undercoat layer, a photographic constituent layer, and a method for producing the same.However, the hardening of a photographic material depends on the factors of the resin-coated paper as a support. It turned out to be greatly affected. Therefore, the present inventors further examined various factors affecting the hardening of photographic materials, and found that the factors depended on factors such as the type and properties of the base paper containing natural pulp as a main component and also greatly depended on the factors of the resin layer. It turned out to be. Factors for the type and properties of the base paper include, for example, the type of natural pulp, stock slurry conditions such as paper additives added to the stock slurry, papermaking speed, papermaking conditions such as drying conditions, size press, Depends on processing conditions such as tab size press and post-processing conditions such as additives contained in the size press liquid, and furthermore, various factors such as synergistic effects of various additive chemicals, density of base paper, moisture content, etc. Turned out to be. The factors of the resin layer depend on various factors such as, for example, the type and density of the resin constituting the front and back resin layers, the additives to be contained, the thickness of the resin layer, and the conditions of the melt extrusion process. The thing turned out. In particular, the lower the moisture content of the resin-coated paper as measured by the microwave moisture meter, the more specifically, it is 9.5% by weight or less, more preferably 9.0% by weight or less, and particularly preferably 8. When the content is less than 5% by weight, it has been found that the hardening of a photographic material using a resin-coated paper as a support is extremely insufficient. Further, as the thickness of the back resin layer of the resin-coated paper becomes thinner, specifically, when the thickness is 34 μm or less, further 30 μm or less, particularly 27 μm or less, and more particularly 24 μm or less, the resin-coated paper is supported. The hardening of the photographic material was found to be extremely insufficient.
[0010]
[Problems to be solved by the invention]
Accordingly, an object of the present invention is to use a paper mainly composed of natural pulp as a substrate, and to cover one of the paper substrates on which a photographic constituent layer is provided with a resin layer (A) containing a polyolefin resin, A photographic material in which a photographic component layer is provided via a subbing layer on a resin-coated paper-type photographic material support in which a paper substrate is coated with a resin layer (B) containing a polyethylene-based resin. The purpose of the present invention is to provide a photographic material in which a hardened film having good film properties is excellent. Other objects of the present invention will become apparent from the following description.
[0011]
[Means for Solving the Problems]
As a result of intensive studies conducted by the present inventors to solve the above-mentioned problems, paper containing natural pulp as a main component is used as a substrate, and a paper substrate on which one of the photographic constituent layers is provided is a resin layer containing a polyolefin resin. A photographic material in which a photographic component layer is provided via a subbing layer on a photographic material support coated with (A) and the opposite side of the paper substrate is coated with a resin layer (B) containing a polyethylene resin. The resin layer (B) containing the polyethylene resin has an infrared dichroic ratio defined below in the range of 0.55 to 0.85, and has a positive layer on the undercoat layer surface of the support. It has been found that the object of the invention is achieved by a photographic material characterized by the provision of a photographic constituent layer after application of a potential of at least 100 volts.
[0012]
Infrared dichroic ratio: The resin layer (B) coated on the side opposite to the side on which the image forming layer is provided without the back layer is peeled off from the paper substrate with an aqueous solution of sodium hypochlorite, The infrared absorption spectrum of the peeled film was measured with infrared light polarized by a polarizing plate, and the CH of the polyethylene molecule was measured. _Two 720cm originated from the horizontal vibration ^-1 Before and after 730cm ^-1 720 cm in two infrared absorption peaks before and after ^-1 Find the peak intensity of the front and rear. This peak intensity is 675 cm ^-1 ~ 725cm ^-1 Point with the smallest absorbance in And 7 25cm ^-1 ~ 775cm ^-1 Is a value of the absorbance obtained by using a line connecting the point having the smallest absorbance in the above as a baseline. At this time, 720 cm of infrared light polarized in a direction parallel to the running direction (longitudinal direction) at the time of melt extrusion is used as a base axis. ^-1 720 cm of infrared light polarized vertically with peak intensity A (=) before and after ^-1 The peak intensity A (+) before and after is determined, and the ratio of A (=) / A (+) is defined as the infrared dichroic ratio.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
In the present invention, the infrared dichroic ratio of the resin layer (B) having a back layer can be completely removed by, for example, shaving the back layer on the surface of the resin layer. Further, depending on the structure of the back layer, the binder can be completely removed by dissolving the binder in the back layer using an aqueous solution of sodium hypochlorite or the like so as not to affect the physical properties of the resin layer. At this time, whether or not it has been completely removed can be determined by measuring infrared absorption or the like.
[0014]
An object of the present invention is to (1) merely use a resin layer containing a polyethylene resin (B) having an infrared dichroic ratio of from 0.55 to 0.85, or (2) subbing a support. The object of the present invention can be achieved synergistically by applying the technical requirements of (1) and (2) together by providing a photographic constituent layer after applying a potential of plus 100 volts or more to the layer surface. It has been found that the present invention has been made.
[0015]
The resin layer (B) containing a polyethylene resin preferably has an infrared dichroic ratio of 0.75 or less, particularly preferably 0.65 or less, and 0.55 or more. It has been found that by use, the objects of the invention are more synergistically achieved. Further, the object of the present invention is to provide a potential applied to the undercoat layer surface of the support, preferably at least 250 volts, more preferably at least 500 volts, particularly preferably at least 750 volts. Have been found to be more remarkably achieved synergistically, and have arrived at the present invention.
[0016]
As the polyethylene resin contained in the back resin layer (B) used in the practice of the present invention, various polyethylene resins are useful as long as the infrared dichroic ratio is 0.85 or less. However, in view of the effect of improving the hardening of the photographic material, those having an infrared dichroic ratio of 0.75 or less are more preferable, those having an infrared dichroic ratio of 0.65 or less, and those of 0.55 or more are particularly preferable. . When the infrared dichroic ratio is less than 0.55, the moldability of the resin composition for the back resin layer tends to deteriorate. The polyethylene resin for the back resin layer used in the practice of the present invention has a melt flow rate defined by JIS K 6760 of 10 g / 10 min to 40 g / 10 min, and a density of 0.960 g / cm. ³ 90 parts by weight to 65 parts by weight of the high-density polyethylene resin described above, the melt flow rate specified by JIS K 6760 is 0.2 g / 10 min to 3 g / 10 min, and the density is 0.935 g / cm. ³ A compound resin composition obtained by previously melting and mixing 10 parts by weight to 35 parts by weight of the following low-density polyethylene resin or medium-density polyethylene resin is preferable.
[0017]
The high-density polyethylene resin for the back resin layer preferably used in the practice of the present invention has a density of 0.960 g / cm. ³ The melt flow rate specified in JIS K 6760 (hereinafter, the melt flow rate specified in JIS K 6760 is simply referred to as MFR) is in the range of 10 g / 10 min to 40 g / 10 min. As long as the resin layer (B) has an infrared dichroic ratio of 0.85 or less, various densities, MFRs, molecular weights, and molecular weight distributions can be used alone or in combination. Various materials such as ordinary high-density polyethylene resins, copolymers of ethylene with α-olefins such as propylene and butylene, and mixtures thereof can be used.
[0018]
The MFR of the high-density polyethylene resin for the back resin layer preferably used in the practice of the present invention is in the range of 10 g / 10 min to 40 g / 10 min, particularly preferably 10 g / 10 min to 30 g / 10 min. Range. If the MFR of the resin is lower than 10 g / 10 min, the infrared dichroic ratio tends to increase, the hardening of the photographic material tends to be poor, and the adhesion between the base paper and the resin layer, the high-speed processability, etc. are poor. If it is higher than 40 g / 10 minutes, the mixing property of the resin, the moldability and the like are deteriorated. The density of the high-density polyethylene resin is 0.960 g / cm ³ Above, but with a density of 0.960 g / cm ³ If it is lower, the elastic modulus of the resin layer is lowered, and the curl physical properties, stiffness, etc. are deteriorated, which is a problem, and is preferably 0.962 g / cm. ³ That is all.
[0019]
The low-density polyethylene resin or medium-density polyethylene resin for the back resin layer preferably used in the practice of the present invention has a density of 0.935 g / cm. ³ Hereinafter, as long as the MFR is in the range of 0.2 g / 10 min to 3 g / 10 min and the infrared dichroic ratio of the resin layer (B) is 0.85 or less, various densities are available. Those having MFR, molecular weight and molecular weight distribution can be used alone or in combination. For example, high-pressure low-density polyethylene resin (autoclave low-density polyethylene resin, tubular low-density polyethylene resin), linear low-density polyethylene resin, medium-density polyethylene resin, copolymer of ethylene with α-olefins such as propylene and butylene. Various materials such as polymers, carboxy-modified polyethylene resins and mixtures thereof can be used.
[0020]
The MFR of the low-density polyethylene resin or the medium-density polyethylene resin for the back resin layer preferably used in the practice of the present invention is in the range of 0.2 g / 10 min to 3 g / 10 min. If the time is shorter than 10 minutes, the mixing properties of the resin, the adhesion between the base paper and the resin layer, the high-speed processability, etc. are deteriorated, which is a problem. If the time is longer than 3 g / 10 minutes, the infrared dichroic ratio tends to increase. The problem is that the hardening of the photographic material tends to be poor, and the moldability is poor, more preferably from 0.2 g / 10 min to less than 2 g / 10 min, particularly preferably from 0.2 g / 10 min to 1 g. / 10 min. The density of the low-density polyethylene resin or the medium-density polyethylene resin is 0.935 g / cm ³ Less than or equal to 0.935 g / cm ³ If it is higher, the molding processability of the resin composition, the adhesiveness between the base paper and the resin layer, etc. are deteriorated, which is a problem, and is preferably 0.930 g / cm. ³ It is as follows. The molecular weight distribution of the resin preferably has a molecular weight of 500,000 or more with a fraction of 10% by weight or more, particularly preferably 12% by weight or more. If the fraction of the resin having a molecular weight of 500,000 or more is less than 10% by weight, molding processability, particularly neck-in, is undesirably increased. Here, the molecular weight was measured using Waters 150-C (column: GMH-XL HT manufactured by Tosoh Corporation, 8 mmφ × 30 cm × 3, solvent: 1,2,4-trichlorobenzene, temperature: 135 ° C., flow rate: 1 ml / min) by the GPC method.
[0021]
The amount of the high-density polyethylene resin in the compound resin composition comprising the high-density polyethylene resin and the low-density or medium-density polyethylene resin preferably used in the practice of the present invention is 90 parts by weight to 65 parts by weight, preferably Ranges from 85 parts by weight to 70 parts by weight. If the amount of the resin used is less than 65 parts by weight, the infrared dichroic ratio of the resin layer (B) becomes high and the hardening of the photographic material becomes poor, which is a problem. The problem is getting worse. On the other hand, if the amount is more than 90 parts by weight, the mixing properties of the resin, the moldability, the adhesion between the base paper and the resin layer, and the like are deteriorated.
[0022]
As the polyethylene resin for the back resin layer used in the practice of the present invention, a compound resin prepared by melting and mixing in advance is preferable. As a method for preparing a compound resin by previously melting and mixing a low-density polyethylene resin or a medium-density polyethylene resin and a high-density polyethylene resin, a simple melt mixing method, a multi-stage melt mixing method, or the like can be used. For example, using an extruder, a twin-screw extruder, a heating roll mill, a Banbury mixer, a pressure kneader, and the like, a predetermined amount of low-density or medium-density polyethylene resin and high-density polyethylene resin, and if necessary, an antioxidant A method of adding various additives such as a lubricant, melting and mixing, and then pelletizing the mixture is advantageously used. If the polyethylene resin is not added as a compound resin but directly added to the melt extruder in the state of simple mixing and melt extrusion coated, the adhesion between the base paper and the resin layer, the mixing properties of the resin, the molding process It is a problem that the properties are worsened.
[0023]
The side on which the photographic component layer of the base paper of the photographic material support used in the practice of the present invention is provided is covered with a resin layer (A) containing a polyolefin resin. Examples of the polyolefin resins include homopolymers such as polyethylene, polypropylene, polybutene and polypentene, copolymers composed of two or more α-olefins such as ethylene-butylene copolymer, and mixtures thereof. Polyethylene resins are particularly preferred from the viewpoint of coating properties and adhesion to base paper.
[0024]
As the polyethylene resin for the surface resin layer preferably used in the practice of the present invention, low-density polyethylene resin, medium-density polyethylene resin, high-density polyethylene resin, linear low-density polyethylene resin, ethylene and propylene, α such as butylene -Various types such as copolymers with olefins, carboxy-modified polyethylene resins and the like and mixtures thereof can be used. Further, those having various densities, MFRs, molecular weights and molecular weight distributions can be used, and usually, the density is 0.91 g / cm. ³ ~ 0.97g / cm ³ , A MFR of 0.3 g / 10 min to 45 g / 10 min, preferably 1 g / 10 min to 30 g / 10 min, and a molecular weight of 20,000 to 250,000 can be used singly or as a mixture.
[0025]
The support for a photographic material used in the practice of the present invention is formed into a film form from its slit die on a running base paper by using a resin extruder for a resin composition for a back resin layer and a resin composition for a front resin layer. It is preferred to be manufactured by a so-called melt extrusion coating method of casting and coating. Usually, using a melt extruder on a running base paper, extruding the molten resin composition from the slit die into a film, casting and coating, pressure-bonded between a pressure roll and a cooling roll, It is produced in a series of steps of being separated from the chill roll. At that time, the temperature of the molten film is preferably 280 to 340 ° C. As the slit die, a flat die such as a T-type die, an L-type die and a fishtail type die is preferable, and the slit opening diameter is desirably 0.1 mm to 2 mm. Further, it is preferable to perform an activation treatment such as a corona discharge treatment or a flame treatment on the base paper before coating the resin composition on the base paper. Further, as described in JP-B-61-42254, a resin layer may be coated on a running base paper after spraying an ozone-containing gas onto a molten resin composition on a side in contact with the base paper.
[0026]
Further, the front and back resin layers are preferably sequentially and preferably continuously coated on the base paper by a so-called tandem extrusion coating method. It may be coated by a multi-layer extrusion coating method, which has a multi-layer structure of more than layers. In the case where the resin layer has a multilayer structure, the present invention uses, for example, an outermost layer resin having an MFR of 5 g / 10 min to 20 g / 10 min, and a lower layer resin having an MFR of 2 g / 10 min to 10 g / 10 min. Resins having different properties and constitutions can be used within a range satisfying the requirements. The surface resin layer surface of the support for photographic materials can be processed into a glossy surface, a finely rough surface described in JP-B No. 62-19732, a matte surface or a silk surface, and the back resin layer is usually matte. It is preferable to process the surface.
[0027]
The thickness of the front and back resin layers of the photographic material support used in the practice of the present invention is not particularly limited, but the thickness of the front resin layer is preferably in the range of 9 μm to 60 μm. And preferably in the range of 12 μm to 45 μm. The thickness of the back resin layer is usefully in the range of 7 μm to 60 μm, preferably in the range of 14 μm to 40 μm, and particularly preferably in the range of 20 μm to 34 μm. Further, the difference in the resin coating amount between the front and back resin layers was reduced to 3 g / m by reducing the coating amount of the back resin layer as compared with the front resin layer. ² It is preferable to make the above.
[0028]
Various additives can be contained in the front and back resin layers of the support for photographic materials used in the practice of the present invention. Titanium oxide, zinc oxide and talc described or exemplified in JP-B-60-3430, JP-B-63-11655, JP-B1-38291, JP-B1-38292 and JP-A-1-105245. , White pigments such as calcium carbonate, fatty acid amides such as stearamide, arachidic amide, zinc stearate, calcium stearate, aluminum stearate, magnesium stearate, zinc palmitate, zinc myristate, and fatty acid metals such as calcium palmitate Salts, various antioxidants such as hindered phenols, hindered amines, phosphorus-based, sulfur-based and the like described in JP-A-1-105245, blue pigments and dyes such as cobalt blue, ultramarine, celian blue, and phthalocyanine blue; Cobalt violet, fass Violet, magenta pigments and dyes such as manganese violet, JP-A fluorescent whitening agent according or exemplified in JP-2-254440, various additives such as an ultraviolet absorber are appropriately combined with can be incorporated. These additives are preferably incorporated as a resin masterbatch or compound. In particular, as a method of incorporating these additives into the compound resin composition for the back resin layer preferably used in the practice of the present invention, a method of previously adding to a high-density polyethylene resin and a low-density polyethylene resin or a medium-density polyethylene resin Alternatively, a masterbatch may be added at the time of preparing the compound resin, or a masterbatch added at a high concentration to the resin may be prepared in advance, and the masterbatch may be added to the resin at the time of melt extrusion coating.
[0029]
On the backing resin layer surface of the photographic material support used in the practice of the present invention, after performing an activation treatment such as a corona discharge treatment or a flame treatment, various back layers are coated for antistatic and the like. be able to. Further, the back layer may contain an inorganic antistatic agent such as colloidal silica, colloidal alumina, hectorite clay colloid described in or exemplified in JP-A-5-107688 and a mixture thereof, a binder, an organic antistatic agent, or both. A water-soluble synthetic polymer compound having a carboxyl group or a sulfone group or a salt thereof or a hydrophilic synthetic polymer colloid substance or a salt thereof described in or exemplified in JP-A-59-214849 for the purpose of Polymer latex described or exemplified in JP-A-214849, starch described or exemplified in JP-A-58-14131, polyvinylpyrrolidone described or exemplified in JP-A-58-45248, JP-A-62-220950 Polyvinyl alcohol described or exemplified in the gazette, JP Polymers such as chitosan described or exemplified in JP 63-189859, hardeners described or exemplified in JP-B-58-56859, matting agents and surfactants described or exemplified in JP-A-59-21849 And the like can be appropriately combined and contained.
[0030]
The photographic material in the present invention is obtained by applying a potential of at least 100 volts to the undercoat layer surface of a support for a resin-coated paper type photographic material and then providing a photographic constituent layer. Therefore, the support for photographic materials used in the practice of the present invention is preferably a support in which a subbing layer is previously applied to the surface of the surface resin layer containing the polyolefin resin on the side on which the photographic constituent layer is provided.
[0031]
The undercoat layer used in the practice of the invention preferably contains gelatin from the viewpoint of the adhesiveness between the photographic constituent layer and the surface resin layer. Examples of such gelatin include lime-processed gelatin, acid-processed gelatin, enzyme-processed gelatin, gelatin derivatives, such as gelatin reacted with an anhydride of dibasic acid, and low-molecular-weight gelatin. The low molecular weight gelatin referred to herein means a gelatin having a molecular weight of 70,000 or less, preferably 500 to 60,000, particularly preferably 1000 to 40,000, and preferably a viscosity of 1 to 2 cps as determined by the PAGI method. In addition, other hydrophilic polymers such as modified polyvinyl alcohol and starch compatible with gelatin in combination with gelatin, hydrolyzates of styrene / maleic anhydride copolymers, sodium polystyrene sulfonate, sulfates of polysaccharides Gelatin thickeners such as compounds can also be used. Further, the pH of the undercoat layer coating solution is preferably in the range of pH 4 to pH 9.5, particularly preferably in the range of pH 5 to pH 8, from the viewpoint of the effect of improving the hardening of the photographic material.
[0032]
Various additives can be contained in the undercoat layer used in the practice of the present invention. Examples of preservatives include p-hydroxybenzoic acid ester compounds, benzisothiazolone compounds, and isothiazolone compounds described and exemplified in JP-A-1-102551, and examples of surfactants described and described in JP-A-1-16635 are exemplified. Fobetaine type surfactant, anionic surfactants such as alkyl benzene sulfonates and sulfosuccinates described or exemplified in JP-A-62-30246 and JP-A-62-44733, saponins, alkylene oxides Nonionic surfactants, such as fluorinated surfactants described in or exemplified in JP-B-47-9303, U.S. Pat. No. 3,589,906, etc., amino acids, esters of amino alcohols, etc. As an amphoteric surfactant and a hardening agent, No. 30244, JP-A-62-230245 or organic hardeners such as active halogen compounds, vinyl sulfone compounds, aziridine compounds, epoxy compounds, acryloyl compounds, isocyanate compounds, etc., chromium alum, sulfuric acid In addition to an inorganic hardening agent such as chromium, a toning agent, a fluorescent whitening agent, a matting agent, a fogging inhibitor or a stabilizer, a pH adjuster, and the like can be appropriately combined.
[0033]
As a method of providing the undercoat layer on the polyolefin resin surface used in the practice of the present invention, after coating the running base paper surface with the polyolefin resin, the photographic component layer is provided on the resin surface on the side where the photographic constituent layer is provided before winding. It is preferable to apply and coat a coating liquid for an undercoat layer to form an undercoat layer, that is, a so-called on-machine method. Alternatively, the resin-coated paper may be wound up, and if necessary, the wound up may be stored, and then a new undercoat layer may be provided, that is, a so-called off-machine method. Examples of the device for applying the undercoat layer coating liquid include an air knife coater, a roll coater, a bar coater, a wire bar coater, a blade coater, a slide hopper coater, a curtain coater, a gravure coater, a flexographic gravure coater, and combinations thereof. Can be Prior to application, it is desirable that the resin surface be subjected to activation treatment such as corona discharge treatment or flame treatment before application. Various drying devices such as a hot air dryer such as a straight tunnel dryer, an arch dryer, an air loop dryer and a sine curve air float dryer, an infrared dryer, a heating dryer, and a microwave dryer are used as a drying device for the applied coating liquid. Can be given. Drying conditions are optional, but generally drying is performed at 60 to 150 ° C. for several seconds to 10 minutes.
[0034]
Further, the coating amount of the undercoat layer is preferably 0.005 to 1.0 g / m 2 in view of the adhesion between the photographic constituent layer and the surface resin layer. ² , Preferably 0.01 to 0.3 g / m ² , More preferably 0.015 to 0.1 g / m ² Range. The drying after the application of the undercoat layer coating liquid is preferably performed without setting.
[0035]
In the practice of the present invention, as a method for applying a potential of 100 volts or more to the undercoat layer surface of the support for photographic materials, a polarity of a grit-controlled ionization apparatus type described or exemplified in JP-A-3-501702 is exemplified. A method in which a potential is applied using a charge generation device is preferable. Further, a method in which a high voltage is applied to a DC electrode formed on a backup roller of a photographic material support described in or exemplified in JP-A-63-4881, and a potential is applied can be used. The potential applied to the undercoat layer surface of the photographic material support is preferably at least 250 volts, more preferably at least 500 volts, particularly preferably at least 750 volts from the viewpoint of the effect of improving the hardening of the photographic material. Preferably, plus a few kilovolts or less is useful from a practical standpoint. On the other hand, even if a negative potential is applied as the potential applied to the undercoat layer surface of the photographic material support, the effect of the present invention of improving the hardened film of the photographic material is hardly or not obtained at all.
[0036]
The base paper used in the practice of the present invention is a natural pulp paper whose main component is ordinary natural pulp. Further, a mixed paper made of natural pulp as a main component and synthetic pulp and synthetic fiber may be used. Such natural pulp is described or exemplified in JP-A-58-37642, JP-A-60-67940, JP-A-60-69649, JP-A-61-35442 and the like. It is advantageous to use such appropriately selected natural pulp. Natural pulp was subjected to normal bleaching treatment of chlorine, hypochlorite, chlorine dioxide bleaching and alkali extraction or alkali treatment and, if necessary, oxidative bleaching treatment with hydrogen peroxide, oxygen, etc., and a combination treatment thereof Wood pulp of softwood pulp, hardwood pulp, and softwood mixed pulp is advantageously used, and various pulp such as kraft pulp, sulfite pulp, soda pulp, and other recycled pulp (waste paper pulp) can be used.
[0037]
Various additives can be contained in the base paper mainly composed of natural pulp used in the practice of the present invention when preparing the stock slurry. Examples of the sizing agent include fatty acid metal salts, fatty acids or a combination thereof, an alkyl ketene dimer emulsion described in JP-B No. 62-7534 or exemplified, an epoxidized higher fatty acid amide or a combination thereof, alkenyl or alkyl succinic anhydride. Emulsions, rosin derivatives, etc., as dry paper strength enhancers, anionic, cationic or amphoteric polyacrylamide, polyvinyl alcohol, cationized starch, vegetable galactomannan, etc., as wet paper strength enhancers, polyamine polyamide epichlorohydrin resin As fillers, clay, kaolin, calcium carbonate, titanium oxide, etc., as fixing agents, aluminum chloride, water-soluble aluminum salts such as bansulfate, etc., as pH regulators, caustic soda, sodium carbonate, sulfuric acid, etc. 63-204251 It is advantageous to incorporate color pigments, coloring dyes, fluorescent whitening agents and the like described or exemplified in JP-A-1-266637 and the like in an appropriate combination.
[0038]
In addition, a composition comprising various water-soluble polymers or hydrophilic colloids or latexes, an antistatic agent, and additives is placed in a base paper or a base paper mainly composed of natural pulp used in the practice of the present invention. Alternatively, it can be contained or coated by coating such as tab size press, blade coating, or air knife coating. As a water-soluble polymer or hydrophilic colloid, starch-based polymers described in or exemplified in JP-A-1-266637, polyvinyl alcohol-based polymers, gelatin-based polymers, polyacrylamide-based polymers, cellulose-based polymers, etc., as emulsions and latexes, Petroleum resin emulsion, emulsion or latex of a copolymer containing at least ethylene and acrylic acid (or methacrylic acid) as described or exemplified in JP-A-55-4027 and JP-A-1-180538, styrene Belts such as butadiene-based, styrene-acryl-based, vinyl acetate-acryl-based, ethylene-vinyl acetate-based, butadiene-methyl methacrylate-based copolymers and emulsions or latexes of carboxy-modified copolymers thereof; Examples of the inhibitor include alkali metal salts such as sodium chloride and potassium chloride, alkaline earth metal salts such as calcium chloride and barium chloride, colloidal metal oxides such as colloidal silica, and organic antistatic agents such as polystyrene sulfonate. , As pigments, clay, kaolin, calcium carbonate, talc, barium sulfate, titanium oxide, etc., as pH regulators, hydrochloric acid, phosphoric acid, citric acid, caustic soda, etc., as well as the above-mentioned coloring pigments, coloring dyes, fluorescent brighteners, etc. It is advantageous to incorporate the additives in an appropriate combination.
[0039]
The thickness of the base paper used in the practice of the present invention is not particularly limited, but its basis weight is 20 g / m2. ² ~ 250g / m ² Is useful, but 50 g / m ² ~ 210g / m ² Are preferred. The base paper used in the practice of the present invention has a water content of 7% by weight or more, preferably 7.5% by weight or more, and 9.5% by weight from the viewpoint of the effect of improving the hardening of the photographic material. % Are useful. The moisture of the base paper can be measured with a microwave moisture meter (Moistrex MX5000, manufactured by Infrared Engineering Co., Ltd.).
[0040]
The base paper used in the practice of the present invention preferably has a thickness unevenness index Rpy of 250 mV or less, more preferably 200 mV or less, and most preferably 150 mV or less, as defined below. . The film thickness non-uniformity index Rpy referred to here is a value obtained by moving a sample between two spherical styluses and using a film thickness measuring device that measures a change in thickness of the sample as an electric signal via an electronic micrometer. Under the condition that the sensitivity range of the sample is ± 15 μm / ± 3 V, the sample is scanned at a constant speed of 1.5 m / min after the zero point adjustment in the papermaking direction to measure the thickness variation in the papermaking direction of the sample. The signal value is subjected to fast Fourier transform using a FFT analyzer using a Hanning window as a time window, and a power spectrum obtained by averaging 128 times of integration (unit: mV) ² ) Is obtained by summing the power values in the frequency range of 2 Hz to 25 Hz and multiplying by 2/3 and raising the value to the 乗 power (unit: mV).
[0041]
As a method for producing a base paper having a thickness unevenness index Rpy of 250 mV or less, which is preferably used in the practice of the present invention, specifically, hardwood pulp which is short fiber and easily smooth is 30% by weight or more, preferably 50% or more. It is beaten with a beater so that the long fiber content is as small as possible. For example, it is preferable that the pulp is beaten so that the weighted average fiber length of the pulp after beaten is 0.4 to 0.65 mm. Then, a base paper is preferably formed by using a fourdrinier paper machine by using an appropriate papermaking method for the stock slurry to which the internal additive has been added so that a uniform formation can be obtained. Specifically, for example, a wet part using a fourdrinier paper machine having an appropriate upper dewatering mechanism as described or exemplified in JP-A-61-284762, which gives an appropriate turbulence to a stock slurry. As a press, a multi-stage wet press, preferably a three-stage or more wet press, and a smooth paper roll is provided at the final stage of the press part, so that a uniform formation can be obtained by combining appropriate papermaking methods. After the papermaking, the paper is subjected to a calendering process using a machine calender, a super calender, a heat calender, or the like, so that a base paper having a film thickness unevenness index Rpy of 250 mV or less can be produced.
[0042]
As the base paper mainly composed of natural pulp used in the practice of the present invention, the papermaking direction at a cutoff value of 0.8 mm measured using a stylus type three-dimensional surface roughness meter on the front side of the base paper Central plane average roughness SRa (hereinafter, the term “center plane average roughness SRa in the papermaking direction at a cutoff value of 0.8 mm measured using a stylus type three-dimensional surface roughness meter on the front side of the base paper, It is useful that the surface roughness is simply 1.45 μm or less, preferably 1.40 μm or less, more preferably 1.35 μm or less, and more preferably 1.25 μm or less. Is particularly preferred. The center plane average roughness SRa at a cut-off value of 0.8 mm measured using a stylus type three-dimensional surface roughness meter referred to in the present specification is defined by Formula 1.
[0043]
(Equation 1)

[0044]
In Equation 1, Wx represents the length of the sample surface area in the X-axis direction (papermaking direction), Wy represents the length of the sample surface area in the Y-axis direction (direction perpendicular to the papermaking direction), and Sa represents the sample surface area. Indicates the area of the area.
[0045]
As a method of producing a base paper having a center plane average roughness SRa of 1.45 μm or less, which is preferably used in the practice of the present invention, specifically, a sulphite pulp which is easily smooth, preferably a hardwood sulphite pulp Is used in an amount of 30% by weight or more, preferably 50% by weight or more, and a multi-stage press is performed during the drying of the wet paper. For example, machine calendering and / or thermal machine calendering are performed on the base paper as a first series of calendering, and then machine calendering is further performed as necessary for the second and subsequent calenders. A thermal soft calendering process described or exemplified in Japanese Unexamined Patent Publication No. Hei 4-110939 is performed to Roughness SRa can be produced the following base paper 1.45 .mu.m. Further, various water-soluble polymers or hydrophilic colloids or polymer latexes are coated in a base paper or on a base paper by a size press or a tab size press, a blade coating, an air knife coating or the like to obtain a solid coating amount of 1.0 g / m ² Above, especially 2.2 g / m ² It is preferable to contain or coat the above.
[0046]
The photographic material according to the present invention includes the photographic material support of the present invention on which various photographic constituent layers are provided, for color photographic printing paper, for black-and-white photographic printing paper, for reversal photographic material, and for silver salt. Diffusion transfer method Negative, positive, and dye diffusion transfer methods and the like are included. For example, those provided with silver chloride, silver bromide, silver chlorobromide, silver iodobromide, and silver chloroiodobromide emulsion layers are included. Includes silver halide color photographic materials in which a color coupler is contained in a silver halide photographic emulsion layer. In addition, those having a photographic component layer for silver salt diffusion transfer method are also included. Particularly useful photographic materials according to the present invention are an undercoat layer, a blue-sensitive silver halide photographic emulsion layer containing a yellow coupler and an interlayer, and a green-sensitive silver halide photographic emulsion layer containing a magenta coupler on a photographic material support. This is a multilayer silver halide color photographic material in which an ultraviolet absorbing layer, a red-sensitive silver halide photographic emulsion layer containing a cyan coupler, and a silver halide color photographic constituent layer such as a protective layer are provided in order. As a binder for these photographic constituent layers, in addition to ordinary gelatin, hydrophilic polymer substances such as polyvinylpyrrolidone, polyvinyl alcohol, and a polysaccharide sulfate compound can be used. Further, the above-mentioned photographic constituent layer can contain various additives. For example, as sensitizing dyes, cyanine dyes, merocyanine dyes, etc., as chemical sensitizers, water-soluble gold compounds, sulfur compounds, etc., as antifoggants or stabilizers, hydroxy-triazolopyrimidine compounds, mercapto-heterocyclic compounds, etc. As a stain inhibitor, dialkyl hydroquinone compounds, etc., as well as a fluorescent brightener, a sharpness improving dye, an antistatic agent, a pH adjuster, a fogging agent, and water-soluble iridium when forming and dispersing silver halide, and water-soluble Rhodium compounds and the like can be appropriately combined and contained.
[0047]
It is preferable that various coating aids are contained in the photographic constituent layer of the photographic material according to the present invention. Examples of such coating aids include anionic surfactants such as alkylbenzene sulfonates and sulfosuccinates described or exemplified in JP-A-62-30246 and JP-A-62-44733; Sulfobetaine surfactants described or exemplified in JP-A-1666035, nonionic surfactants such as Sanipon and alkyl oxides, JP-A-47-9303, U.S. Pat. No. 3,589,906, etc. It is preferred that various coating aids such as the fluorinated surfactants described or exemplified above are incorporated alone or in combination.
[0048]
Further, it is preferable that various hardeners are contained in the photographic constituent layer of the photographic material according to the present invention. Examples of these hardeners include active halogen compounds, vinyl sulfone compounds, aziridine compounds, epoxy compounds, acryloyl compounds, isocyanate compounds described or exemplified in JP-A-62-30244 and JP-A-62-30245. It is preferable to include various hardeners such as an arbodiimide compound and an isoxazole compound alone or in combination. The content of the hardener varies depending on the type of gelatin, which is the main polymer in the photographic constituent layer, the type of photographic material, the development processing conditions, etc., but generally with respect to the gelatin in the coating solution for the photographic constituent layer. The range is from 0.05% to 10% by weight, preferably from 0.1% to 5% by weight, based on the dry weight of gelatin. The hardener may be added at any stage of adjusting the coating solution. In particular, when the hardener is added to the silver halide emulsion, it is generally added after the chemical ripening (second ripening) of the silver halide emulsion. Good to do. Further, the hardening agent may be added to each layer of the photographic constituent layer in a small amount in the silver halide photographic emulsion layer and in a large amount in the non-photosensitive layer, or in a photographic constituent layer far from the support. It is preferable to employ various addition formulations such as adding a small amount to the photographic constituent layer close to the support.
[0049]
In the practice of the present invention, as a method of applying a coating solution for a photographic constituent layer on a support for a photographic material having an undercoat layer, a coating method suitable for producing a multilayer silver halide color photographic printing paper is selected. Is preferred. As a typical coating method, a multilayer slide hopper system in which a coating solution for a multilayer photographic constituent layer is caused to flow down from a multilayer slide hopper and a coating solution for a multilayer photographic constituent layer is simultaneously applied to a support while forming a multilayer bead, so-called, It can be applied by the E-bar coating method. As another typical coating method, a coating solution for a multilayer photographic component layer is caused to flow down from a multilayer slide hopper to form a curtain in a gravitational field, and preferably while both ends of the curtain are stabilized by a guide, and It is preferred to apply the coating solution for the multilayer photographic constituent layer simultaneously on the support under a reduced pressure while eliminating the deformation of the curtain, that is, a so-called curtain coating method. The coating speed is at least 150 m / min, preferably at least 200 m / min, particularly preferably at least 300 m / min, from the viewpoint of productivity of the photographic material.
[0050]
The photographic material according to the present invention may be used in accordance with the photographic material, such as exposure, development, stop, fixing, as described in "Photosensitive Material and Handling Method" (Kyoritsu Shuppan, Goro Miyamoto, Photographic Technology Course 2). Processing such as bleaching and stabilization can be performed. Further, the multi-layer silver halide color photographic material may be processed with a developer containing a development accelerator such as benzyl alcohol, thallium salt, phenidone or the like, or may be processed with a developer substantially free of benzyl alcohol. it can.
[0051]
【Example】
Next, examples will be described in order to more specifically describe the present invention.
[0052]
Example 1
Fiber length of pulp after beating a mixed pulp composed of 30% by weight of hardwood bleached kraft pulp and 70% by weight of hardwood bleached sulphite pulp (JAPAN TAPPI Paper Pulp Test Method No. 52-89 "Paper and Pulp Fiber Length Test Method") The fiber was beaten so that the length measured in accordance with the formula (expressed as a length-weighted average fiber length) was 0.58 mm, and then 3 parts by weight of cationized starch and 0.2 part by weight of anionic polyacrylamide were added to 100 parts by weight of pulp. Parts, alkyl ketene dimer emulsion (as ketene dimer) 0.4 parts by weight, polyamide epichlorohydrin resin 0.4 parts by weight and appropriate amounts of fluorescent whitening agent, blue dye and red dye are added to prepare a stock slurry. did. Thereafter, the stock slurry is placed on a fourdrinier paper machine running at 200 m / min to form a web while giving an appropriate turbulence, and a linear pressure of 15 kg / cm to 100 kg / cm is applied in the wet part. After performing the adjusted three-stage wet press, treated with a smoothing roll, and performed a two-stage tension press in which the linear pressure was adjusted in the range of 30 kg / cm to 70 kg / cm in the subsequent drying part, Dried. Then, during the drying, 25 g / size press solution consisting of 4 parts by weight of carboxy-modified polyvinyl alcohol, 0.05 parts by weight of optical brightener, 0.002 parts by weight of blue dye, 4 parts by weight of sodium chloride and 92 parts by weight of water. m ² The paper is subjected to size press, dried so that the finally obtained base paper moisture becomes 8% by weight by a microwave moisture meter, machine calendered at a linear pressure of 70 kg / cm, and a basis weight of 170 g / m2. ² A base paper having a thickness unevenness index Rpy of 130 mV and a center plane average roughness SRa of 1.20 μm was manufactured.
[0053]
Next, after subjecting the base paper surface (back surface) opposite to the side on which the photographic component layer is provided to corona discharge treatment, the following resin composition (R1) or (R2) is applied to the back surface at a resin temperature of 315 ° C. and a resin of 23 μm. The thickness was melt-extruded and coated at a running speed of the base paper of 200 m / min. At this time, as the cooling roll, the square value of the center surface average roughness (SRa) of the back layer surface after coating the following back layer was 0.75 μm. ² As the cooling roll, a cooling roll roughened by a liquid honing method was used, and the cooling roll was operated at a cooling water temperature of 12 ° C.
[0054]
(Resin composition R1) High density polyethylene resin (density 0.967 g / cm ³ , MFR = 6.5 g / 10 min) 50 parts by weight and low density polyethylene resin (density 0.926 g / cm) ³ , MFR = 3.5 g / 10 min) The resin composition was simply mixed with 50 parts by weight and added to the melt extruder with simple mixing.
[0055]
(Resin composition R2) High-density polyethylene resin (density 0.967 g / cm ³ , MFR = 15 g / 10 min) 70 parts by weight and a low density polyethylene resin (density 0.924 g / cm) ³ , MFR = 0.6 g / 10 min.) Was used in the form of pellets, prepared by previously melting and mixing 30 parts by weight with a melt extruder.
[0056]
Subsequently, the surface of the base paper was subjected to a corona discharge treatment, and then a low-density polyethylene resin (density 0.920 g / cm ³ , MFR = 8.5 g / 10 min) 47.5% by weight, hydrous aluminum hydroxide (based on titanium dioxide and Al ₂ O ₃ 20 parts by weight of a master batch of a titanium dioxide pigment composed of 50% by weight of anatase type titanium dioxide pigment and 2.5% by weight of zinc stearate surface-treated with 0.75% by weight of a low-density polyethylene resin (density 0.920 g) / Cm ³ , MFR = 4.5 g / 10 min) 65 parts by weight and high density polyethylene resin (density 0.970 g / cm) ³ , MFR = 7.0 g / 10 min) was melt-extruded and coated at a resin temperature of 315 ° C. to a thickness of 30 μm at a running speed of the base paper of 200 m / min. In addition, the melt extrusion coating of the front and back polyethylene resins was performed by a so-called tandem method in which extrusion coating was sequentially performed. At this time, the surface of the resin layer containing the titanium dioxide pigment of the resin-coated paper was processed into a glossy surface.
[0057]
Further, before the front and back resin layers were processed and wound up, the back resin layer surface of the resin-coated paper was subjected to a corona discharge treatment, and then the following back layer coating solution was applied on-machine. In terms of dry weight, colloidal silica: styrene-based latex = 1: 1, and further, polystyrene sodium sulfonate 0.021 g / m 2 ² The coating liquid for the back layer containing an appropriate amount of a coating aid and the like in the amount of latex (calculated as solid weight) is 0.21 g / m2. ² The amount of coating was such that In order to separately measure the infrared dichroic ratio of the back resin layer, a sample having no back layer was also prepared.
[0058]
Further, after coating the back layer and before winding the resin-coated paper, a corona discharge treatment was applied to the resin surface on the front side, and 1.2 g of lime-treated gelatin and low molecular weight gelatin (manufactured by Nitta Gelatin Co., Ltd .; -3226) containing 0.3 g, 0.3 g of a 10% by weight methanol solution of butyl paraoxybenzoate and 0.45 g of a 5% by weight mixture of methanol and water of 2-ethylhexyl sulfosuccinate, and the total amount is 100 g with water. The coating solution for the undercoat layer prepared in the above was coated with a gelatin coating amount of 0.06 g / m2. ² To obtain a support for a photographic material.
[0059]
Subsequently, a potential shown in Table 1 was applied to the undercoat layer surface of the support for photographic material by a polar charge generator of a grit control ionizer type, and then the blue-sensitive emulsion layer containing a yellow color coupler was formed on the undercoat layer. , An intermediate layer containing an anti-color-mixing agent, a green-sensitive emulsion layer containing a magenta-color-forming coupler, an ultraviolet-absorbing layer containing an ultraviolet-ray absorbing agent, a red-sensitive emulsion layer containing a cyan-color-forming coupler, and a multi-layer coating solution for each protective layer. A curtain is applied by a curtain coat method while forming a curtain by flowing down from a slide popper, and the total amount of gelatin (dry weight) is 8 g / m 2. ² Color photographic paper. Each color sensitive emulsion layer is 0.6 g / m2 of silver nitrate. ² In addition to silver chlorobromide corresponding to, in addition to the gelatin required for the formation, dispersion and film formation of silver halide, an appropriate amount of antifoggant, sensitizing dye, coating aid, hardener, thickener and Contains an appropriate amount of filter dye and the like. The viscosity of each coating solution was between 25 centipoise and 100 centipoise (the viscosity of the blue-sensitive emulsion layer coating solution was 25 centipoise), the curtain height was 12 cm, and the coating speed was 210 m / min. In addition, the total amount of gelatin was 8 g / m ² With respect to the total amount of the hardening agent represented by Chemical Formula 1 as 0.06 g / m ² Was appropriately distributed and contained in each coating solution.
[0060]
Embedded image

[0061]
Next, the prepared color printing paper was heated at 35 ° C. and normal humidity for 4 days, and then the hardness of the silver halide color photographic constituent layer of the color printing paper was evaluated. As a method for evaluating the hardness of the silver halide color photographic component layer, a film point of a ball point needle having a ball diameter of 1 mm is developed with a color developing solution at 33 ° C. for 3 minutes and 30 seconds. And the load (hereinafter referred to as film strength) of a ball point needle that causes damage to the film surface when the sample surface was moved at a speed of 2 cm / sec was measured to evaluate the film strength.
[0062]
Table 1 shows the obtained results.
[0063]
[Table 1]

[0064]
Note that (Note 1) and (Note 2) in Table 1 are as follows.
[0065]
(Note 1) ○ indicates a sample according to the present invention.
[0066]
(Note 2) The infrared dichroic ratio of the back resin layer measured by the method described in the description of the sample without the back layer is shown.
[0067]
From the results in Table 1, it can be seen that the undercoat layer surface of the resin-coated paper-type photographic material support in which the base paper is coated with the backing resin layer containing a polyethylene resin and having an infrared dichroic ratio of 0.55 to 0.85 is provided. The photographic materials of the present invention (samples Nos. 8 to 12) in which a silver halide color photographic component layer was provided after applying a potential of plus 100 volts or more, had a hardened film due to their synergistic effect. It can be seen that the material was excellent. Further, it can be clearly understood that the applied potential is preferably 250 volts or more, more preferably 500 volts or more, and particularly preferably 750 volts or more from the viewpoint of the effect of improving the hardening of the photographic material.
[0068]
On the other hand, when an infrared dichroic ratio of more than 0.85 is used as the back resin layer containing the polyethylene resin (Sample Nos. 1 to 6), the potential applied to the undercoat layer becomes lower. When the potential is less than plus 100 volts (Sample No. 7) and when the potential applied to the undercoat layer is negative (Sample No. 13), the photographic material outside the present invention has a problem that its hard film is weak. It is clear that there is.
[0069]
Example 2
Sample No. of Example 1 10 except that the following resin compositions (R1) to (R6) were used in place of the resin composition (R2) used in Sample No. 10. Performed similarly to 10.
[0070]
(Resin composition R1) Same as the resin composition (R1) used in Example 1.
(Resin composition R2) Same as the resin composition (R2) used in Example 1.
[0071]
(Resin composition R3) High-density polyethylene resin (density 0.967 g / cm ³ , MFR = 6.8 g / 10 min) 65 parts by weight and a low density polyethylene resin (density 0.926 g / cm) ³ , MFR = 3.5 g / 10 min) was simply mixed with 35 parts by weight of the resin composition.
[0072]
(Resin composition R4) High-density polyethylene resin (density 0.967 g / cm ³ , MFR = 10 g / 10 min) 65 parts by weight and low density polyethylene resin (density 0.926 g / cm) ³ , MFR = 0.6 g / 10 min.) 35 parts by weight using a melt extruder to melt and mix in advance and used as pellets.
[0073]
(Resin composition R5) High-density polyethylene resin (density 0.967 g / cm ³ , MFR = 10 g / 10 min) 78 parts by weight and a low density polyethylene resin (density 0.926 g / cm) ³ , MFR = 0.6 g / 10 min.) 22 parts by weight using a melt extruder to melt and mix in advance, and used as pellets.
[0074]
(Resin composition R6) High-density polyethylene resin (density 0.967 g / cm ³ , MFR = 15 g / 10 min) 85 parts by weight and low density polyethylene resin (density 0.926 g / cm) ³ , MFR = 0.6 g / 10 min) in a melt extruder and 15 parts by weight in advance to obtain a compound resin composition, which was used as pellets.
[0075]
Table 2 shows the obtained results.
[0076]
[Table 2]

[0077]
Note that (Note 1) and (Note 2) in Table 2 have the same meanings as those in Table 1.
[0078]
From the results shown in Table 2, the photographic materials of the present invention (Sample Nos. 15 to 18) in which the infrared dichroic ratio of the back resin layer is 0.55 to 0.85 are the same as those of the silver halide photographic constituent layer. It is clear that the film is an excellent photographic material that worked well. Further, in view of the effect of improving the hardening and the overall performance such as the moldability of the resin composition, a photographic material having an infrared dichroic ratio of the back resin layer of 0.75 or less is preferable, and 0.65 or less and 0 or less. It can be clearly seen that a photographic material having a .55 or more is particularly preferred. On the other hand, it can be clearly understood that the photographic materials (Nos. 14 and 19) outside of the present invention have problems such as a poor hardness of the photographic materials and insufficient molding workability.
[0079]
Example 3
Sample No. of Example 1 10 except that the back resin layer having a resin thickness shown in Table 3 was used instead of the back resin layer having a resin thickness of 23 μm used in Sample No. 10. Performed similarly to 10. The infrared dichroic ratio of the back resin layer was 0.63.
[0080]
Table 3 shows the obtained results.
[0081]
[Table 3]

[0082]
Note that (Note 1) in Table 3 has the same meaning as in Table 1.
[0083]
From the results shown in Table 3, it can be seen that as the thickness of the backing resin layer of the resin-coated paper-type photographic material support increases, the hardening of the photographic component layer of the photographic material increases. This indicates a unique synergistic effect of the present invention in which the back resin layer affects the hardening of the photographic constituent layer applied to the front resin layer. Also, it can be understood that the thickness of the back resin layer is preferably in the range of 20 μm to 34 μm. If the thickness of the back resin layer is greater than 34 μm, the curl properties of the photographic material and the like are deteriorated, causing a problem.
[0084]
Example 4
In the sample No. of Example 3, Sample No. 23 of Example 3 except that the base paper having the water content shown in Table 1 measured by a microwave moisture meter was used instead of the base paper used in Sample No. 23. 23. The infrared dichroic ratio of the back resin layer was 0.63.
[0085]
Table 4 shows the obtained results.
[0086]
[Table 4]

[0087]
Note that (Note 1) in Table 4 has the same meaning as that in Table 1.
[0088]
From the results shown in Table 4, as the base paper for resin-coated paper used in the practice of the present invention, the moisture content as measured by a microwave moisture meter was 7.5 wt. % Or more and less than 9.5% by weight.
[0089]
Example 5
Example 1 was repeated except that the coating solution for the photographic constituent layer was applied by the E-bar coating method instead of the coating solution by the curtain coating method, and that the coating liquid for the blue-sensitive emulsion layer was 6 centipoise. It carried out similarly and obtained the same result as Example 1.
[0090]
Example 6
Instead of the hardener represented by Chemical Formula 1 used in Example 1, a hardener represented by Chemical Formula 2 was used at 96 mg / m 2. ² The same operation as in Example 1 was carried out except for using the same, and the same result as in Example 1 was obtained.
[0091]
Embedded image

[0092]
【The invention's effect】
According to the present invention, it is possible to provide an excellent photographic material using a resin-coated paper as a support, in which the photographic constituent layers have good film physical properties and the hardening is effective.

Claims (6)

Using a paper mainly composed of natural pulp as a substrate, one of the paper substrates on which a photographic constituent layer is provided is coated with a resin layer (A) containing a polyolefin resin, and the other paper substrate on the other side contains a polyethylene resin. A photographic material comprising a photographic material layer provided on a photographic material support covered with a resin layer (B) via an undercoat layer, wherein the resin layer (B) containing a polyethylene resin is defined as follows. The infrared dichroic ratio is in the range of 0.55 to 0.85, and a photographic constituent layer is provided after applying a potential of 100 V or more to the undercoat layer surface of the support. And photographic materials.
Infrared dichroic ratio: The resin layer (B) coated on the side opposite to the side on which the image forming layer is provided without the back layer is peeled off from the paper substrate with an aqueous solution of sodium hypochlorite, the infrared absorption spectrum of the peeled film was measured with infrared light that is polarized by the polarizing plate, 720 cm ^-1 before and after the 730 cm ^-1 2 two infrared absorption peaks before and after from the rocking vibration of the CH ₂ of polyethylene molecules The peak intensity around 720 cm ^-1 is determined. The peak intensity of absorbance was determined highest absorbance small point and 7 small dots and lines connecting the most absorbance in 25cm ^-1 ~775cm ^-1 in the 675cm ^-1 ~725cm ^-1 as a baseline Value. At this time, the peak intensity A (=) around 720 cm ⁻¹ due to the infrared light polarized in a direction parallel to the running direction (longitudinal direction) at the time of melt extrusion and the infrared light polarized in the vertical direction. The peak intensity A (+) around 720 cm ^-1 is determined, and the ratio of A (=) / A (+) is defined as the infrared dichroic ratio. 2. The photographic material according to claim 1, wherein the undercoat layer contains gelatin. The polyolefin resin in the resin layer (A) is a polyethylene resin, and the polyethylene resin is composed of 15 to 50 parts by weight of a high-density polyethylene resin and 50 to 85 parts by weight of a low-density polyethylene resin. 3. The photographic material according to claim 1, which is a photographic material. 4. A photographic material according to claim 1, wherein the resin layer (A) contains a titanium dioxide pigment. The photographic material according to claim 1, 2, 3 or 4, wherein the thickness of the resin layer (B) containing a polyethylene-based resin is 20 µm to 34 µm. 6. The photographic material according to claim 1, wherein the substrate paper has a water content of not less than 7.5% by weight and less than 9.5% by weight as measured by a microwave moisture meter.