JP3811464B2 - Impression cylinder, intermediate cylinder or covering for guide roller, printing apparatus using the same, and cleaning apparatus in printing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a covering body, which is less stuck and stained with ink while easily cleaned and highly durable, for an impression cylinder or an intermediate cylinder installed on a printing machine, a printing machine and a cleaning unit. <P>SOLUTION: The covering for the impression cylinder, intermediate cylinder or guide roller body is formed by providing, on the surface of a plate-shaped or sheet-shaped article, a composite coating film (14) which comprises a hard base layer having a porous ceramic thermal-sprayed layer (12) or minute irregularities and a low surface-energy resin layer (13) formed on the surface of the ceramic thermal-sprayed layer and inside holes. The composite coating film can be formed on a flexible metal plate and provided in the form of a coating body which can be wound on a roller. A simpler coating body can also be provided by forming a composite coating film, constituted of an inorganic particles layer of ceramic powder glass beads, etc., instead of the ceramic thermal sprayed layer and the low surface-energy resin layer, on a base material such as a synthetic resin film or water-proof treated paper. <P>COPYRIGHT: (C)2004,JPO

Description

【００７７】
（但し、式中、Ｒはそれぞれ独立に水酸基、アルキル、アリール、アルケニル、ハロゲン置換アルキル、ハロゲン置換アリール、ハロゲン置換アルケニル、好ましくはメチル基を表し、ｎは１〜３００００である。） しかしながら、もちろん使用されるシリコーン系樹脂組成物としては、このようなシリコーン離型剤に何ら限定されるものではない。
【００７８】
またこのようなシリコーン系樹脂組成物中には、必要に応じて、皮膜硬度を高めるためのシリカ微粒子等の充填剤を配合することも可能であるが、セラミックス溶射層の空孔部および凹部に十分侵入し得る程度の粒径のものである必要がある。
【００７９】
またフッ素原子含有樹脂としては、ポリクロロトリフルオロエチレン、ポリフッ化ビニリデン、ポリフッ化ビニル等といった熱可塑性フッ素原子含有樹脂を用い、適当な溶剤に懸濁ないし膨潤させて塗布し、溶融温度以上に加熱して成膜するといったディスパージョン加工法を用いることも可能であるが、セラミックス溶射層の表面上および孔部内により確実に皮膜を形成するためには、分子鎖内に少量の水酸基、カルボン酸基等の官能基を有し、液状にて塗布可能でかつ常温または加熱して架橋硬化する熱硬化性フッ素原子含有樹脂の方が望ましく、例えば、フルオロエチレンとアクリル酸、メタアクリル酸との共重合体などが例示される。
【００８０】
形成される低表面エネルギー性樹脂層のセラミックス溶射層表面上における厚さは、前記したようにセラミックス溶射層のうねり波状凹部には厚く、一方うねり波状凸部には薄く付着するため、平均膜厚として規定することは困難である。しかしながら、溶射層の表面を実質的に全面的に覆い、かつセラミックス溶射層のうねり状凹凸を維持したものとなるように、全体を通じて０．５〜２０μｍ程度の厚さにおいて付着することが望ましい。
【００８１】
このようにして得られる本発明の圧胴または中間胴は、最終的な表面性状が滑らかな凹凸を有するものとなり、代表的にはその表面粗度Ｒ_ｍａｘが、２０〜４０μｍ程度であることが望ましく、また最終的な表面における滑らかな凹凸の凸部は、例えば２０μｍ×２０μｍ平方〜１００μｍ×１００μｍ平方当りに１ケ程度、より好ましくは３０μｍ×３０μｍ平方〜６０μｍ×６０μｍ平方当りに１ケ程度の割合で均一に分散して存在することが望ましい。そしてその全表面は、複合被覆皮膜として前記セラミック溶射層に保持された緻密な低表面エネルギー性樹脂層よって形成されており、使用されるインキに対する濡れ性の低いものである。
【００８２】
このため本発明のローラは、各種の印刷機における圧胴または中間胴に配される各種のローラとして好適に使用でき、具体的には例えば、オフセット印刷機における圧胴、あるいはオフセット輪転機（新聞輪転機、商業用オフセット輪転機、フォーム輪転機）、グラビア印刷機、フレキソ印刷機、凸版新聞輪転機等の各種輪転機におけるガイドローラとして好適に使用できるものである。
【００８３】
次に本第２発明の被覆体について詳細に説明する。本第２発明の被覆体は、可撓性基板上に、表面に微細な凹凸を有する硬質ベース層と前記ベース層の表面上に前記凹凸を完全に消失させることなく形成された低表面エネルギー性樹脂層とからなる複合被覆皮膜が形成されてなるものである。
【００８４】
可撓性基板としては、比較的耐圧性、耐久性等を重視する場合には、アルミニウム合金板、ステンレス鋼板等の金属製板材を用いることが、また施工容易性、価格面等を重視する場合には、水、溶剤等の吸収による収縮、熱による伸縮の小さいもの、ローラ表面にうまく密着するようなある程度の可撓性を有するもの、またある程度の引裂き、張力に耐える強度を有しかつカッターナイフ、鋏等による裁断加工の容易なものであるといった観点から、合成樹脂フィルムまたは耐水処理紙などを用いることが例示されるが、もちろんこれらに限定されるものではない。なお、合成樹脂フィルムとしては、ポリエチレン、ポリプロピレンといったオレフィン系フィルム、ポリウレタン系フィルム、ポリエステル系フィルム、ポリ塩化ビニルないしポリ塩化ビニリデン系フィルム、ポリアミド系フィルム等が、また耐水処理紙としては、樹脂含浸紙、耐水処理クラフト紙、あるいはその他の耐水不織紙などが含まれるが、もちろんこれらに何ら限定されるものではない。
【００８５】
なお、可撓性基板の板厚としては、板材の種類、あるいはローラの種類等によっても左右されるものであり、特に限定されるものではないが、例えば０．１〜０．５ｍｍ程度のものが用いられ得る。
【００８６】
このような可撓性基板上部に形成される表面に微細な凹凸を有する硬質ベース層としては、例えば、前記したようなセラミックス溶射層、あるいは複数の無機微粒子により形成されるコーティング層などが例示でき、さらに前記ベース層の表面上に前記凹凸を完全に消失させることなく形成された低表面エネルギー性樹脂層としては、前記したようなシリコーン系樹脂等が用いられる。
【００８７】
ここで、可撓性基板として金属製板材を用い、硬質ベース層としてセラミックス溶射層を用いる場合（第１の実施態様）には、上記第１発明のローラに関する場合と、その施工される金属製ローラ基材が金属製板材に代わるのみで、その製造方法、製造条件、各層の材質ないし特性値等はほぼ同一であるため詳細な説明を省略する。製造方法についてのみ概略すれば、金属製板材に対し、まず周知の手法により脱脂・ブラスト処理を行ない表面を粗し、次に、必要に応じて金属あるいは金属合金溶射層を形成した後、公知のセラミックス溶射法を用いることにより、セラミックス溶射層を形成し、さらにその上部から低表面エネルギー性樹脂を含浸、コーティングし、所定の温度で乾燥固化させ、セラミックス溶射層の表面上および孔部内に低表面エネルギー性樹脂層を形成して複合被覆皮膜層とするものである。
【００８８】
次に、硬質ベース層として無機微粒子層を形成する場合について説明する。使用される無機微粒子としては、各種セラミックス粉体、ガラスビーズ、硬質金属粒子等が用いられるが、好ましくは各種セラミック粉体、ガラスビーズである。これらの微粒子の大きさは、特に限定されるものではないが、平均粒径３０〜２００μｍ程度のものでかつ粒径分布の狭い粒径の揃ったものがよく、またその形状としては球形ないしは球形に近いものが、印刷紙および印刷面を損傷しないという観点から好ましい。これらの微粒子は、多孔質のものであってもあるいは実質的に無孔質のものであってもよい。多孔質のものである場合、後述する低表面エネルギー性樹脂の付着性が良好なものとなるが、一方で強度的に弱くかつ価格的にも高価なものとなる場合が多い。無孔質のものである場合、逆に低表面エネルギー性樹脂の付着性は低下するものの、強度面および価格面では有利である。従って、当該被覆体が施工されるローラの使用条件等に応じて多孔質のものか無孔質かは適宜選択すればよい。
【００８９】
このような無機微粒子を、可撓性基材、特に合成樹脂フィルムまたは耐水処理紙などの基材上部に付着させるのには、一般に接着剤が使用される。使用される接着剤は、十分な耐水性および耐溶剤性を有し、かつ使用される基材および無機微粒子ならびに上部に付与される低表面エネルギー性樹脂との被着性ないし濡れ性が良好なものを適宜選択して使用する。特に限定されるものではないが、例えばアクリル系接着剤、エポキシ系接着剤、クロロプレン系接着剤、シアノアクリレート系接着剤、ウレタン系接着剤、ＳＢＲ系接着剤、ブチルゴム系接着剤、ＳＢＳ・ＳＩＳ系接着剤等が使用され得る。また基材が熱可塑性の合成樹脂フィルムである場合には、無機微粒子の熱溶着（合成樹脂フィルムの部分的溶融）による直接付着といった態様も考えられる。
【００９０】
このような無機微粒子を基材上部に付着させる場合、その付着させた後の表面粗度が適当な値、例えばＲ_ｍａｘ３０〜１５０μｍになるように、無機微粒子の頭が露出する状態で付着させる必要がある。すなわち、無機微粒子が接着剤層等内に完全に埋没してしまうと、ローラに粗面を付与する被覆体としての機能が果せなくなるためである。また、基材上に付着させた無機微粒子は、全体に均一に付着する限り、二層ないしそれ以上積層された状態となっていてもよいが、図５に示すように一層のみとなっている方が、微粒子の剥離等の不具合が発生する虞れが小さく、安定した特性を示すために望ましい。
【００９１】
このように無機微粒子層を形成した後、この上部に上述したと同様にシリコーン系樹脂等を用いて、この無機微粒子層上部に低表面エネルギー性樹脂層を形成し、複合被覆皮膜とする。この低エネルギー性樹脂層の無機微粒子層上における厚さは、無機微粒子の露出頭部には薄く、一方、粒子相互の間に形成される谷部には比較的厚くさせるが、前記頭部および谷部で形成される凹凸を完全に消失させることなく滑らかな凹凸を残すような状態とする必要がある。例えば、無機微粒子の頭部には約２μｍ程度、一方谷部には約５〜１０μｍ程度の厚さとして付着させることが望ましい。なお、具体的な低エネルギー性樹脂の種類およびその塗布方法等は前記と同様である。なお、低エネルギー性樹脂と無機微粒子（および前記谷部として一部露出する接着剤あるいは基材）との被着性向上のため、例えば、公知のカップリング剤等を使用した化学的前処理あるいは各種の物理的前処理等を行なうことも可能である。
【００９２】
このようにして得られる本第２発明の第２態様に係る被覆体も、最終的な表面性状が滑らかな凹凸を有するものとなるが、その表面粗度Ｒ_ｍａｘは、２０〜１５０μｍ程度であることが望ましい。
【００９３】
なお、本第２発明の第２態様に係る被覆体の場合、基材として合成樹脂フィルムまたは耐水処理紙などを用いることができるため、例えばロール状に巻かれた長尺の基材に対し、無機微粒子コーティングおよび低エネルギー性樹脂コーティングを行なうということができ、高い製造効率を達成できる。そして、巻装しようとする圧胴、中間胴、ガイドローラ等のローラそれぞれに必要なサイズに容易に裁断して適用できる。
【００９４】
本第２発明の被覆体をローラ本体に取付ける方法としては、捩子止め、接着によるもの、あるいはローラ本体にクランプ装置、巻軸を有する巻締め装置を設けたものなどが採用され得るが、殊に第２態様の被覆体の場合、両面接着テープ等を用いて容易に貼着することができる。
【００９５】
上記したような本第１発明のローラ、あるいは本第２発明の被覆体を巻装してなるローラの構成あるいは当該被覆体の構成は、印刷機の分野のみならず、前記したような印刷物におけるインキと同様に、粘着移行性物質が表面に付与されたフィルム状体を処理するローラないしその表面被覆体として、同様にこれらの粘着移行性物質によるローラの汚染が生じにくくかつ耐久性の高いものとして好適に使用できることは明らかである。印刷機における圧胴、中間胴またはガイドローラ以外の適用例としては、例えば、各種複写機における被印写体の圧着・移送系におけるローラ等が例示されるが、もちろんこれらに限定されるものではない。
【００９６】
また本第１発明の圧胴または中間胴、あるいは本第２発明の被覆体を巻装してなる圧胴または中間胴を用いてなる印刷機においては、これらの圧胴または中間胴に対する清浄装置を有することが好ましい。このような清浄装置は、被印刷体の移送経路あるいはその他の装置構成と干渉しない部位において、圧胴または中間胴の面に対し接触し得る清浄体を有するものであればよい。この清浄体はローラ面に対し、印刷終了時のみ接触しうる構成としても、印刷作業時においても適宜接触・離間しうる構成としてもよい。清浄体は、乾式のものでも十分な清浄効果を付与できるが、より高い清浄効果を得る上では溶剤を含浸させた湿式のものが望まれる。なお清浄体は、フェルト、不織布、布材、紙材等の柔軟で吸収性のある材質により構成することができる。また、ローラ面に対し、固定接触する構成としても、回転接触する構成とすることも可能である。
【００９７】
特に、例えば新聞輪転機等の１ロットの印刷が多い印刷機の場合、ロット途中でのガイドローラ洗浄は従来不可欠であり、主なガイドローラには洗浄装置（湿式）が備えられていたが、本発明に係るガイドローラを使用することによって、ロット途中でのローラ洗浄は不要となり、また作業終了時でのローラ上のわずかなインキ汚れも上記のごとき簡単な構成の清浄装置の清浄体をローラ面に軽く押圧して拭き取るという簡単な操作で、必要十分な清浄効果を得ることができるものである。また新聞輪転機等の場合、紙を空通しして、ローラの回転速度を紙の送り速度よりも速くあるいは遅くし、ローラ面と紙面とをスリップさせることことによっても、清浄作業を行なうことができる。なお、従来、新聞輪転機においては、ローラ面に溶剤を付与しローラ面上のインキを溶かした後、このようなスリップを行なうことによって清浄作業が行なわれているが、本発明のローラを用いた場合には、溶剤を用いることなく乾式にてスリップさせることのみで十分な清浄効果が得られる。
【００９８】
さらにオフセット印刷機の圧胴に対する清浄機構としては、より簡便な構成とすることができる。すなわち、本発明に係る圧胴を使用したオフセット印刷機における圧胴清浄装置としては、圧胴に対向するゴム胴のローラ面に押圧可能な清浄体を備え、かつ、前記清浄体をゴム胴へ押圧した状態において一定時間の間圧胴をゴム胴へ接触回転させるものとするシーケンス制御機構を有してなるものでよい。このような構成を有するものであると、印刷作業終了時において、ゴム胴のローラ面に前記清浄体を押圧し、ゴム胴を回転させている状態で、ゴム胴と圧胴の接触をオンとし、ゴム胴と共に圧胴を回転させてやれば、圧胴上のインキ汚れはゴム胴上へと逆転写され、さらにゴム胴上の汚れとして清浄体で拭き取ることができるためである。
【００９９】
【実施例】
以下、本発明を実施例によりさらに具体的に説明する。
【０１００】
参考例１
厚さ０．３ｍｍのＳＵＳ３０４製の金属板の表面を、脱脂、ブラスト処理して表面を粗した。なおこの際の表面粗度Ｒ_ｍａｘは約１０μｍであった。
【０１０１】
その後、粉末粒径１０〜５５μｍのＮｉ−Ｃｒ合金を用い、プラズマ溶射にて前記シリンダー表面に膜厚約３０μｍのＮｉ−Ｃｒ溶射層を形成し、続いて粉末粒径１０〜４４μｍのＧ−Ａｌ_２Ｏ_３を用い、同様にプラズマ溶射して膜厚約７０μｍのセラミックス溶射層を形成した。このセラミック溶射層の表面粗度Ｒ_ｍａｘは約４０μｍであり、図２に図示するように非常にシャープな突起を有しながらうねる粗面であった。またセラミックス溶射層は０．１〜数十μｍの大きさの空孔を有しており、空孔率は約１６％であった。このようにして得られた被覆体をダクタイル鋳鉄製の金属シリンダーの表面に巻装して圧胴を得た。この圧胴を以下のような印刷試験に供した。
【０１０２】
実施例１
上記参考例１と同様の手順を行なった後、セラミックス溶射層の上から、シリコーン系樹脂離型剤（信越化学工業（株）製 ＫＳ７７６Ｌ）１００部、トルエン３００部および硬化触媒（信越化学工業（株）製 ＣＡＴ−ＰＬ８）１部を混合攪拌した溶液を、スプレー方式で含浸塗布した後、１５０℃の乾燥炉で１時間乾燥固化させてセラミックス溶射層の表面にシリコーン系樹脂皮膜を形成した。このシリコーン系樹脂皮膜は、セラミックス溶射層の連通空孔部を完全に閉塞し、かつ溶射層の表面において、うねり波状凹凸の凹部には厚くかつ凸部には薄く付着しその全面を完全に覆っているものであり、その膜厚は各部位によって相違するが２〜２０μｍの範囲にあった。そしてこのシリコーン系樹脂皮膜形成後における表面粗度Ｒ_ｍａｘは約３０μｍであり、図１または図２に図示するように滑らかな凹凸を有する粗面であった。このようにして得られた圧胴を参考例１と同様に以下のような印刷試験に、更に以下のような耐傷性試験に供した。
【０１０３】
印刷試験１
上記参考例１および実施例１において作成した圧胴を、オフセット印刷機（（株）小森コーポレーション製、菊全両面機）に取付け、紅インキ（東洋インキ（株）製、ハイプラス）を使用して、コート紙３万枚に対し、両面印刷を行なった。なお比較対照のために、通常のクロムメッキ後研磨した圧胴を使用して同様の印刷試験を併せて行なった。その結果、参考例１の圧胴を使用した場合には、圧胴の表面が砂目状の凹凸形状となっている分、通常のクロムメッキの圧胴と比較すると、圧胴表面のインキ汚れは少ないが、紙通し枚数が増えるとどんどん汚れがひどくなり、約３０００枚を越えるころには、この圧胴のインキ汚れに起因する印刷物の裏汚れが顕著となり、実用上採用出来ないことが判明した。またセラミックス溶射層の表面の鋭利な突起部で、印刷物のベタ部のインキを取り去ることによって、数μｍの微細な素抜け（白抜け）が無数に出来、目視によっても明らかに印刷の鮮明性が劣るものとなっていた。
【０１０４】
一方、実施例１の圧胴の場合、３万枚の印刷を行なった後でも、圧胴表面の微細な凸部に極わずかなインキが付着しているのみであり、しかもこのインキ付着量はさらに紙通し枚数を増やしてもほとんど変化なくインキ付着が成長しないものであった。さらに、印刷物のベタ部に当接する部位においても圧胴表面の突起部にインキがほとんど転写されておらず、素抜けも非常に少なくかつ小さいものであり、印刷物の印刷品質上ほとんど障害にならず、良好な印刷物を得ることができた。
【０１０５】
また印刷試験終了後、圧胴表面に付着したインキの除去を試みたところ、実施例１のものにおいては、乾いた布で軽く拭き取るのみでわずかに付着したインキを完全に除去できたが、比較対照のクロムメッキの圧胴の場合、このような処理で取除くことは困難で、白灯油を用いて洗浄しないと除去することができず、さらに参考例１の圧胴の場合、このような有機溶剤を用いても表面の微細な凹部に入り込んだインキが完全には除去できず、かつ溶剤に溶解し流動性の生じたインキが気孔内へと浸み込んでいくために洗浄困難であった。
【０１０６】
耐傷性試験
実施例１で得られた圧胴の表面硬度を、鉛筆硬度試験により調べたところ４Ｈであり、しかも、鉄製の工具（ドライバ）を強く押しつけてこすっても、圧胴上には一旦は金属色の傷状の跡が付くが、その上を指先で拭くとこの跡はきれいに消失した。すなわち、実施例１の圧胴表面に傷が付いたのではなく、工具が削れてその滓が圧胴上に付着しただけのものであった。これは、前記工具とは、圧胴表面微細な突起部のみが工具と接触するだけであり、この突起部は耐磨耗性の高いセラミックス溶射層の上に極薄くシリコーン系樹脂皮膜が付着しているのみであって実質的に前記溶射層の硬度の影響が強く生じるためであると考えられる。なお、この突起部においてはシリコーン系樹脂皮膜が直接的には、工具と接触するものの、非常に微細な点として接触しているのみであり面として接触していないため、これらの非常に微細な突起部のみにおいてシリコーン系樹脂皮膜が磨耗除去されるのみであり、シリコーン系樹脂皮膜が面として剥ぎ取られることはない。
【０１０７】
一方比較対照のために、実施例１で使用したシリコーン系樹脂、あるいは特開昭６２−９４３９２号で開示されるいくつかのシリコーン系樹脂を、ブラスト処理前の滑らかな表面性状の鋳鉄シリンダー表面に直接コーティングして得られた試験体の表面硬度を、鉛筆硬度試験により調べたところＢ〜２Ｈであり、工具等の硬いもので軽く擦るのみで簡単に傷が付いた。
【０１０８】
参考例２
アルミニウム合金製のパイプにより作製されたローラの表面を脱脂、ブラスト処理して表面を粗した。なおこの際の表面粗度Ｒ_ｍａｘは約３５μｍであった。その後、粉末粒径１０〜５５μｍのＮｉ−Ｃｒ合金を用い、プラズマ溶射にて前記シリンダー表面に膜厚約３０μｍのＮｉ−Ｃｒ溶射層を形成し、続いて粉末粒径１０〜４４μｍのＧ−Ａｌ_２Ｏ_３を用い、同様にプラズマ溶射して膜厚約７０μｍのセラミックス溶射層を形成した。このセラミック溶射層の表面粗度Ｒ_ｍａｘは約４０μｍであり、図２に図示するように非常にシャープな突起を有しながらうねる粗面であった。またセラミックス溶射層は０．１〜数十μｍの大きさの空孔を有しており、空孔率は約１６％であった。このようにして得られたガイドローラを以下のような印刷試験に供した。
【０１０９】
実施例２
上記参考例２と同様の手順を行なった後、セラミックス溶射層の上から、シリコーン系樹脂離型剤（信越化学工業（株）製 ＫＳ７７６Ｌ）１００部、トルエン３００部および硬化触媒（信越化学工業（株）製 ＣＡＴ−ＰＬ８）１部を混合攪拌した溶液を、スプレー方式で含浸塗布した後、１５０℃の乾燥炉で１時間乾燥固化させてセラミックス溶射層の表面にシリコーン系樹脂皮膜を形成した。このシリコーン系樹脂皮膜は、セラミックス溶射層の連通空孔部を完全に閉塞し、かつ溶射層の表面において、うねり波状凹凸の凹部には厚くかつ凸部には薄く付着しその全面を完全に覆っているものであり、その膜厚は各部位によって相違するが２〜２０μｍの範囲にあった。そしてこのシリコーン系樹脂皮膜形成後における表面粗度Ｒ_ｍａｘは約３０μｍであり、図１に図示するように滑らかな凹凸を有する粗面であった。このようにして得られたガイドローラを参考例２と同様に以下のような印刷試験に供した。
【０１１０】
印刷試験２
上記参考例２および実施例２において作成したガイドローラを、それぞれフォーム輪転機（（株）ミヤコシ製、ＭＶＦ１８）に取付け、墨、藍、紅、黄のプロセスインキでカラー絵柄の印刷を、上質紙に対し、連続４０時間を行なった。なお比較対照のために、通常のアルミニウム合金製ロールでローレット加工したものをガイドローラとして使用して同様の印刷試験を併せて行なった。
【０１１１】
その結果、参考例２のガイドローラを使用した場合には、良好な耐スリップ性が得られ、また表面が砂目状の凹凸形状となっている分、比較対照のローレット加工したアルミニウム合金製ガイドローラと比較すると、インキ汚れは少なく約１／２の洗浄頻度であったが、紙通し枚数が増えるとどんどん汚れがひどくなり、約１０時間を越えるころには、このガイドローラのインキ汚れに起因する印刷物の汚れが顕著となり、実用上採用出来ないことが判明した。
【０１１２】
一方、実施例２のガイドローラの場合、４０時間の印刷を行なった後でも、表面の微細な凸部に極わずかなインキが付着しているのみであり、しかもこのインキ付着量はさらに紙通し枚数を増やしてもほとんど変化なくインキ付着が成長しないものであった。このため、肉眼で確認できる程の印刷物の汚れは４０時間の連続運転後も生じず、途中でガイドローラを清掃することなく、良好な印刷品質の印刷物を得ることができた。
【０１１３】
また印刷試験終了後、ガイドローラ表面に付着したインキの除去を試みたところ、実施例１のものにおいては、乾いた布で軽く拭き取るのみでわずかに付着したインキを完全に除去でき、印刷装置内に備えられるガイドローラーの清浄装置としては乾式のもので十分であることを示唆するものであった。一方、比較対照のものの場合、このような処理で取除くことは困難で、白灯油を用いて洗浄しないと除去することができず、印刷装置内に備えられる清浄装置も、有機溶剤を用いた湿式の洗浄装置が必要であることが確認された。さらに参考例２のガイドローラの場合、このような有機溶剤を用いて洗浄した場合、溶剤に溶解し流動性の生じたインキが気孔内へと浸み込んでいくために非常に洗浄が行ないにくく、従来の有機溶剤を用いた湿式の洗浄装置によっても十分な洗浄効果が得れないとの結論を得た。
【０１１４】
実施例３
低表面エネルギー性樹脂被膜を、シリコーン系樹脂離型剤（信越化学工業（株）製 ＫＮＳ３１６）１００部、トルエン１００部および硬化触媒（信越化学工業（株）製 ＣＡＴ−ＰＬ５６）３部を混合攪拌した溶液を用いて形成する以外は実施例１と同様にして圧胴を作製し、前記と同様に印刷試験、耐傷性試験を行なったところ実施例１と同様に優れた結果が得られた。
【０１１５】
実施例４〜７
低表面エネルギー性樹脂被膜を、シリコーン系樹脂としてＫＲ２０４６（実施例４）、Ｘ−４０−２１４１（実施例５）、Ｘ−４１−９７１０Ｈ（実施例６）、またはＸ−４０−２０１（実施例７）（いずれも信越化学工業（株）製）を用いて形成する以外は、実施例１と同様にして圧胴を作製し、前記と同様に印刷試験を行なった。印刷試験終了後の圧胴面上の汚れの度合に若干の相違が見られたものの、いずれのものにおいても、実施例１と同様に良好な印刷品質が保たれ、かつ印刷終了後の圧胴の汚れも乾式にて完全に除去できるものであった。
【０１１６】
参考例３
厚さ１００μｍの合成樹脂フィルム（ポリプロピレン系）に、直接シリコーン系樹脂離型剤（信越化学工業（株）製 ＫＮＳ３１６）を膜厚３μｍの厚さにコーティングした試験片を作製した。
【０１１７】
参考例４
参考例３と同じ合成樹脂フィルムに平均粒径２００μｍのガラスビーズを接着剤（アクリル系）により、ガラスビーズがフィルム全面を覆いかつガラスビーズが一層だけ均一に分散するように接着させて試験片を作製した。なお得られた試験片の表面粗度は、Ｒ_ｍａｘ１４０μｍであった。
【０１１８】
実施例８
参考例４と同じ方法で、フィルム表面にガラスビーズを接着させた後、参考例３で用いたと同じシリコーン系離型剤をこのガラスビーズ層の上部からコーティングした。なおシリコーン系離型剤は、ガラスビーズの頭部では約２μｍと比較的薄く、一方ガラスビーズ間の谷部では約５〜１０μｍと比較的厚くコーティングされ、得られた試験片の表面粗度はＲ_ｍａｘ１３３μｍとなっていた。
【０１１９】
このようにして得られた参考例３、４および実施例８の試験片に対し、以下のようなガムテープ剥離試験および印刷試験に供した。
【０１２０】
ガムテープ剥離試験 参考例３、４および実施例８の試験片表面の付着性を確認するため、市販のガムテープ（幅２５ｍｍ×長さ１００ｍｍ）を試験片表面に貼着し、これを剥離する際に要する力を測定した。
【０１２１】
その結果、初期段階で、実施例８および参考例３についてはガムテープはほとんど付着しない状態（剥離力５ｇ未満）であったが、参考例４については１１０ｇの力を要した。なお、比較対照たるポリプロピレン系樹脂フィルムそのものにおける剥離力は４８０ｇであった。
【０１２２】
次に表面磨耗による剥離力の経時的変化を調べるため、それぞれの試験片を直径１００ｍｍのロールに、それぞれシリコーン系樹脂層ないしガラスビーズ層が表面側に向くように両面接着テープで取付け、その上にコート紙を巻角９０°、テンション力２００ｇ／ｃｍで取付け、コート紙側を固定し、ローラを回転させて摺動磨耗テストを行なった。なお、コート紙表面には、インキを定期的に塗布した紙を用いた。そして所定回転数毎に上記したようなガムテープ剥離試験を実施した。それぞれの試験片について得られた累積回転数と剥離力との関係を図１０に示す。
【０１２３】
図１０に示す結果から明らかなように、参考例３の試験片は、シリコーン系樹脂離型剤が表面に存在する間は参考例４のものよりも剥離力が大幅に小さいが、少ない累積回転数（約１０００回転）で離型剤が磨耗脱落し、剥離力が急速に高まっている（すなわち、耐汚染性能の低下）。また参考例４のものは初期段階では比較対照たる樹脂フィルムのみのものと比較して、ガラスビーズで凹凸面を形成させている効果が出て、剥離力が小さいが、累積回転数が大きくなるに従い、インキ及び紙粉が凹面に付着堆積していき、剥離力が高くなる（耐汚染性能の低下）。これに対し、実施例８のものでは初期段階で剥離力がほぼ０のものが累積回転数が大きくなるに従い剥離力はわずかに大きくなるが、その増大は極めてゆるやかで、長期間にわたって耐汚染性能を維持する。これは離型剤の磨耗脱落が、ガラスビーズの凸部のみで、凹部の離型剤はほとんど磨耗脱落せずそのまま残っているため、凹部にインキ及び紙粉が付着堆積せず、参考例４の場合のような耐汚染性能の低下につながらないものであると思われる。
【０１２４】
印刷試験３
上記参考例３、４および実施例８で作製した試験片を、アキヤマ印刷機製造（株）製、ＪＰ−４０両面印刷機の中間胴に両面粘着テープを用いて巻装し、実機にて操業比較テストを行なった。使用した紙はコート紙、インキは東洋インキ（株）製、ハイプラスとし、版はベタ部の多い絵柄のテスト版でインキ厚盛り印刷を行なった。
【０１２５】
その結果参考例３のものを使用した場合、初期段階では、当然インキ反撥性の高い表面となっているが、表面の摩擦係数が高いために中間胴表面と紙面での紙離れ性はあまり良くない。このため第１中間胴→第２中間胴→圧胴へと紙を受渡していく場合、中間胴と紙間では微小なズレが生じるが、中間胴と紙間で紙離れが悪いとそこで擦れが生じ印刷面の傷、汚れが発生した。またこの試験片は、印刷部数の増加とともに表面のシリコーン離型剤層が磨耗・脱落し、１ヵ月位でシ−ト面へのインキ付着が急に増大し、印刷物の傷・汚れも非常に目立つようになり実用に耐えるものではなかった。
【０１２６】
また参考例４のものを使用した場合、５０００〜１００００枚位の印刷で、中間胴がかなり汚れてこれが印刷物のダブリ、汚れとなるため、長持間印刷機を連続稼働することが不可能で、機械を停止してガソリン等で洗浄する必要がある。この試験片は、印刷面との接触が点接触であるため、紙との摩擦を少なくする点では有効と言えるが、ガラスビーズ自体にはインキ反撥性がほとんどなく、特に凹部に付着堆積したインキ・紙粉等の汚染物質は非常に洗浄しにくい。これらの洗浄除去に要する時間・労力は印刷工程のうち大きな割合を占めていた。また毎回の洗浄で落ちきれない汚れが凹部に堆積してインキ反撥性がより一層低下していくため、１〜３ヵ月で新しいシートとの取換えが必要であった。また洗浄に用いられる溶剤によるシートの劣化も無視できない事項であった。
【０１２７】
これに対し実施例８のものを使用した場合、中間胴面の汚れが非常に少なく、１日６万枚の連続印刷でも中間胴汚れによる印刷物の汚れ・ダブリは全く発生しなかった。わずかに付着したインキ汚れも、洗浄油を浸した布で拭き取ることにより簡単に除去でき、凹部での汚れ残りも非常に少ないものであった。すなわち、中間胴汚れによる印刷物不良率の発生減少、洗浄頻度の大幅減少による生産性の向上と労働負荷の減少で、多大な効果があり、またインキ反撥性の長持間持続による寿命の大幅向上が可能となった。
【０１２８】
【発明の効果】
以上述べたように、本発明の被印刷体圧着・移送用ローラおよび本発明の被覆体を巻装した被印刷体圧着・移送用ローラは、その表面性状が微細で比較的滑らかな凹凸を有するものであり、耐磨耗性に優れたセラミックス溶射層ないしは無機微粒子層と表面エネルギーの低いシリコーン系樹脂等の低表面エネルギー性樹脂層とからなる複合皮膜で基材表面を被覆しているものであるため、表面にインキが付着し難いものである。このため各種の印刷機における被印刷体圧着・移送系に配される各種のローラ、例えば、オフセット印刷機における圧胴、あるいはオフセット輪転機（新聞輪転機、商業用オフセット輪転機、フォーム輪転機）、グラビア印刷機、フレキソ印刷機等の各種輪転機におけるガイドローラとして好適に使用できるものであり、連続して多量ないし長持間の印刷操作を行なう場合に、洗浄操作を施す必要もなく、汚れのない良好な印刷品質の印刷物を提供できるものとなり、かつその耐久性も優れたものである。さらに、表面に付着したインキも乾式にて容易に除去できるものであることから、従来、非常に危険でかつ重労働であったローラの洗浄操作も極めて容易なものとなり、また非常に簡単な構成の清浄装置を装置内に組込むことで、自動的に清浄化することも可能であり、清掃に費す時間と労力、またイニシャルコストの削減の上でも非常に高い効果を与えるものである。さらに、例えばビジネスフォーム輪転機等においては、逆転写の不具合を解消するためにＵＶインキを使用することが行なわれていたが、本発明のガイドローラを用いることによって、インキ自体がコスト的に高くまたおよび装置構成が複雑かつコスト高になるＵＶインキを使用しなくとも、通常のインキで同等の印刷レベルを達成することが可能となる。
【０１２９】
また、本発明の被覆体において、基材として合成樹脂フィルムまたは耐水処理紙などを使用した態様においては、その生産性に優れかつ既設の各種印刷機の様々なサイズの非印刷体圧着・移送ローラに対しても任意のサイズに容易に裁断して巻装可能であり、その適用範囲が非常に広いものとなる。
【０１３０】
さらに、このような構成を有するローラは、印刷機の分野のみならず、粘着移行性物質が表面に付与されたフィルム状体を処理するその他の分野における各種ローラとしても、同様の優れた効果を奏するものである。
【図面の簡単な説明】
【図１】 本発明に係る圧胴または中間胴用被覆体の一実施態様における断面構造を模式的に示す図、
【図２】 本発明に係る圧胴または中間胴用被覆体の断面構造をさらに拡大して模式的に示す図、
【図３】 本発明に係る圧胴または中間胴用被覆体の製造過程における断面構造を模式的に示す図、
【図４】 本発明に係る圧胴または中間胴用被覆体の第１の実施態様を被印刷体圧着・移送用ローラに巻装する状態を模式的に示す断面図、
【図５】 本発明に係る中間胴またはガイドローラ用被覆体の第２の実施態様の断面構造を模式的に示す図、
【図６】 オフセット印刷機における印刷機構の概略的な構成を示す図、
【図７】 オフセット印刷における両面印刷時の圧胴のインキ汚れを説明する模式図、
【図８】 オフセット印刷機における圧胴およびゴム胴と被印刷体の関係を示す図であり、（ａ）は幅狭の被印刷体に印刷している状態、（ｂ）は幅広の被印刷体に印刷している状態をそれぞれ示す図、
【図９】 別のオフセット印刷機（輪転機）における被印刷体の印刷および移送機構の概略的な構成を示す図、
【図１０】 本発明の実施例において得られた各種被覆体表面の付着特性の経時的変化を示すグラフ。
【符号の説明】
１…版胴、
２…ゴム胴、
３…圧胴、
４…被印刷体、
５…インキ像、
６，８…転写インキ像、
７…ガイドローラ、
１０，２２…金属製ローラ基材、
１１，２３…金属溶射層、
１２，２４…セラミックス溶射層、
１３，２５，３４…低表面エネルギー性樹脂層、
１４，２６，３５…複合被覆皮膜、
２０…ローラ本体、
２１…被覆体、
３２…基材（合成樹脂フィルムまたは耐水処理紙）、
３３…無機微粒子層、
３６…接着剤層。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pressure drum, an intermediate drum or a cover for a guide roller, a printing apparatus using the same, and a cleaning device in various printing apparatuses.
[0002]
[Prior art]
The printing technique is a technique for copying a large amount of text and other graphic information as a hard copy (printed material) in which a homogeneous image is formed on the surface of a printing medium such as paper. In such a printing technique, as is well known, as a printing apparatus used to make a printed material by attaching a color material (ink) to a printing plate and then pressure-transferring it to the surface of the printing material, the printing plate type and Depending on the difference in the ink transfer form (direct printing or indirect printing method) from the printing plate to the surface of the printing material, various types such as offset printing machines, letterpress printing machines, flexographic printing machines, gravure printing machines, screen printing machines, etc. is there.
[0003]
In these printing apparatuses, there is a difference in whether the printing plate is directly bonded to the printing medium, or an intermediate medium such as a rubber blanket to which the ink attached to the printing plate is once transferred is bonded to the printing medium, The large concept of transferring the ink on the printing element (printing plate or intermediate medium) to the printing medium is the same, and the printing medium is pressure-bonded to the printing element and then transferred. -There are many common configurations for the transfer system.
[0004]
FIG. 6 is a diagram showing a schematic configuration of a printing mechanism in an offset printing machine. In an offset printing machine, ink is transferred from a plate cylinder 1 to a rubber cylinder (rubber blanket) 2 and then transferred onto the surface of the printing medium 4 fed between the rubber cylinder 2 and the impression cylinder 3. Then, an ink image (printed material) 5 is formed.
[0005]
Conventionally, as an impression cylinder of an offset printing machine, a metal cylinder surface usually finished with chrome plating has been used, but double-sided printing was performed with a printing machine equipped with an impression cylinder of such a configuration. In this case, the printing medium 4 after the first surface printing is fed between the rubber cylinder 2 and the impression cylinder 3 having the same configuration as described above (that is, the ink image 5 is formed) in the next step as shown in FIG. When the first surface of the printed material comes into contact with the pressure drum 3 side), the ink image 5 printed on the first surface is transferred onto the surface of the pressure drum 3 as a transfer ink image 6 and subsequently sent. As a result of the transfer ink image 6 being transferred again to the same surface of the printing medium 4 to be printed, the printing surface is contaminated (hereinafter referred to as “back stain”). If double-sided printing was repeated, this tendency became worse and printing unevenness was generated.
[0006]
In the case of single-sided printing, as shown in FIGS. 8A and 8B, the size of the printing medium 4 to be used ranges from a wide one to a narrow one. As shown in FIG. 2, when printing on a narrow substrate 4, the rubber cylinder 2 and the impression cylinder 3 are in direct contact with each other in a width portion where the substrate 4 does not exist (because a strong printing pressure is applied). The rubber cylinder 2 dents the portion corresponding to the thickness of the printing medium 4), and a slight stain ink on the plate cylinder 1 is transferred to the impression cylinder 3 through the rubber cylinder 2 and becomes impression cylinder stains. Next, when the wide printing medium 4 passes while the impression cylinder is dirty, there is a problem that dirt on the impression cylinder adheres to the printing medium 4 and the printed matter is stained.
[0007]
Therefore, when the double-sided printing as described above is repeated, or when changing from narrow printing to wide printing, the impression cylinder 3 must be washed. Since the ink adhering to the surface of the impression cylinder 3 is difficult to remove easily, the printing machine is stopped, the hand is extended to a narrow part in a very unstable posture, and a waste cloth containing an organic solvent is used. The pressure drum 3 was forced to be wiped while being manually rotated one after another.
[0008]
In order to solve such problems, Japanese Patent Application Laid-Open No. 62-94392 proposes an impression cylinder in which the surface of a metal cylinder is coated with a specific silicone resin.
[0009]
However, if the surface of the metal cylinder is simply coated with a silicone resin, the resulting silicone resin film has a low hardness, so the performance is significantly degraded due to scratches and wear. It proved impractical to use as a difficult part. In addition, when such a silicone-based resin film is directly formed on the surface of the metal cylinder, the surface property becomes extremely smooth and flat. Since the silicone resin exhibits non-adhesive surface properties with low surface energy, the ink transfer from the printing medium 4 was found to be quite large.
[0010]
FIG. 9 is also a drawing showing a schematic configuration of a printing and transport mechanism for a printing medium in another offset printing machine. This example is a rotary type using continuous paper wound in a roll shape as the printing material 4, and ink is transferred from the plate cylinder 1 to the rubber cylinder 2 in the same manner as described above. The ink-jet image 5 is formed on the surface of the printing medium 4 fed between the impression cylinders 3 to form an ink image 5. It passes through the apparatus while being redirected by the guide roller 7.
[0011]
In a rotary press that continuously prints on a printing medium such as paper or film wound in a roll shape as described above, a large number of guide rollers are provided in the transfer system of the printing medium. The transfer system using such guide rollers is not limited to the above-described offset rotary press (newspaper rotary press, commercial offset rotary press, foam rotary press), but also a gravure printing press, flexographic printing press, letterpress rotary press. A rotary press such as the same is also included.
[0012]
As the guide roller 7 for a rotary press, many aluminum alloy pipes are used for weight reduction. Of course, in addition to this, there are also known ones in which the surface of an iron pipe is plated with chrome, or ones using carbon fiber reinforced resin or the like for further weight reduction. Furthermore, in order to prevent the printing material from slipping and ink adhesion, these guide roller surfaces are knurled, taped with a sandpaper-like rough surface, and ceramic sprayed. Are known. However, the knurled aluminum alloy pipe has low wear resistance, and the knurled irregularities disappear in a short period of time, and slip easily occurs. Similarly, even when a sandpaper-like rough surface tape was applied to the roller surface, the sand beads were dropped and the tape was peeled off after a short period of use, and could not withstand long-term use. On the other hand, the ceramic sprayed surface has a very high wear resistance and a very good effect in terms of slip resistance, but the following ink adhesion problems become significant. There was a drawback.
[0013]
That is, the surface of any conventionally known guide roller is made of a material having a relatively high ink adhesion property. Therefore, even if such a guide roller 7 has a rough surface, When the printing press is operated for a long time, the ink image 5 printed on the surface of the printing medium 4 is transferred as a transfer ink image 8 onto the surface of the guide roller 7 that is in contact with the transfer cylinder 4 as in the case of the impression cylinder described above. A problem similar to that in the above-described impression cylinder, in which the ink image 8 is reversely transferred to the surface of the subsequent printing medium 4 and contamination of the printed matter occurs. For this reason, when operating a rotary press, such guide rollers must be cleaned periodically, interrupting the printing operation for cleaning operations, causing a large cleaning load, and neglecting cleaning. This leads to the occurrence of troubles such as producing defective printed products.
[0014]
In particular, in the case where the ceramic sprayed surface is formed, the ink penetrates into and adheres to the concave portion of the sprayed rough surface, so it cannot be easily removed by wiping the surface, and a solvent is used. When washing is performed, the ink dissolved in the solvent is transferred and impregnated into the pores of the ceramic sprayed layer, so that the washing operation is difficult. Further, Japanese Patent Laid-Open No. 63-102940 proposes to wrap a covering material having a silicone resin as a surface layer and having compressibility around the surface of the intermediate cylinder in order to prevent ink smearing on the intermediate cylinder of the printing press. ing. However, as described above, the coating material made of only the silicone resin coating has extremely poor wear resistance and loses the releasing effect in a very short period due to wear contact, so that it can be applied to members used under the wear action. Absent.
[0015]
In addition, as a member for preventing ink adhesion to the impression cylinder, feed cylinder, and guide roller of the printing press, Japanese Patent Publication No. 53-7841 and Japanese Utility Model Publication No. 61-31740 are provided on substrates such as kraft paper, synthetic paper and resin film. A technique relating to a coating for preventing ink adhesion, which is coated with glass beads, is generally marketed and is applied to an impression cylinder, a feed cylinder and a guide roller. This technology is based on the idea of preventing ink adhesion by making a point contact effect by bringing the head of glass beads into contact with the printing surface. The material is relatively high in surface energy and has a low repellent property against ink. Inhibiting the effect of preventing ink adhesion. In particular, the valleys (recesses) formed between the glass beads are sharp and easy to remain and solidify, and when operated for a certain period of time, ink, paper dust, etc. adhere and accumulate and contaminate the following paper. There is a drawback. For this reason, it is necessary to periodically stop the machine to clean and remove the adhering contaminants with an organic solvent. In this case as well, it is impossible to continuously operate the printing press for a long time, and the time required for removing the contaminants The effort was quite large. In addition, due to repeated use, residual contaminants such as dried and solidified ink remaining in the valleys increase, and the release effect is lost, and it is necessary to replace with a new covering in a short period of time. .
[0016]
Further, in Japanese Examined Patent Publication No. 53-7841, porous beads such as silica gel, alumina, styrene gel or the like are bonded to a sheet-like substrate in place of the glass beads, and moisture is included in the pores of the porous material. Has been disclosed in which the ink is constantly moistened during printing and imparts ink repellent properties. It is stated that hydration in this porous material can be done by spraying or other methods, but if water is sprayed on the sheet surface in use, excess water will adhere to the printing paper surface, causing problems such as color density reduction. Control is very difficult to control. Also, the pores of the porous material are impractical because the ink is clogged and its function is lost in a short time. Furthermore, if the ink repellency effect due to water is lost, as in the case of the sheet with the glass beads adhered, problems due to ink accumulation in the valleys formed between the beads occur, and a large improvement effect is maintained. It was impossible.
[0017]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an improved roller for pressure-bonding / transferring a printing body used in various printing apparatuses or a covering for the roller. Another object of the present invention is to provide a roller for press-fitting and transferring a printed material that has less ink adhesion contamination and is easy to clean, or a covering for the roller. It is another object of the present invention to provide an impression cylinder and an intermediate cylinder for an offset printing press that are less likely to cause problems such as back stains during double-sided printing and printed matter stains due to changes in the width of a printed material during single-sided printing. is there. It is another object of the present invention to provide a guide roller for a rotary press that has good slip resistance with respect to a printing material and is less likely to cause a problem of printed matter stains. It is another object of the present invention to provide a cleaning device that can clean an impression cylinder, a guide roller, and the like of an offset printing machine with a very simple configuration.
[0018]
[Means for Solving the Problems]
  The above-mentioned objects are such that, in a printing apparatus, a printing medium is pressure-bonded to a printing element, and then detachable over substantially the entire circumference of an impression cylinder or an intermediate cylinder arranged in a printing medium pressure-bonding / transferring system to be transferred thereafter. A covering to be wound,Short-period irregularities that form a very sharp protrusion by spraying a porous ceramic sprayed layer having a porosity of 5 to 20% on a substrate made of a degreased and blasted metal plate, and more A rough surface formed by combining long-period unevenness is formed, and the uneven surface layer of the porous ceramic and the inside of the hole are substantially entirely covered, but the long-period concave portion of the ceramic sprayed layer is formed. Is coated with a low surface energy resin so that it adheres thinly to the long-period protrusions.A composite coating film is formed and its surface properties areKeeping the long-period irregularities of ceramic spraying roughlySurface roughness R_max  It is achieved by a coating for an impression cylinder or an intermediate cylinder, which is 20 to 40 μm and has smooth unevenness.
[0019]
In the covering according to the present invention, the low surface energy resin layer is preferably composed of a silicone resin.
[0020]
In addition, the following aspects can be considered for this covering. For example, the roller is preferably applied to a roller (high load portion) having a relatively high printing pressure, such as an impression cylinder or an intermediate cylinder for an offset printing machine, and a substrate made of a metal plate material that has been degreased and blasted. A coated body is formed by forming a composite coating film comprising a porous ceramic sprayed layer and a low surface energy resin layer formed on the surface of the ceramic sprayed layer and in the pores.
[0021]
In the coated body of the above aspect, the surface property of the coated body is a surface roughness R._maxIt is desirable that it has a smooth unevenness of 20 to 40 μm, and that the protrusions of the unevenness are present at a ratio of about 1 per 20 μm × 20 μm square to 100 μm × 100 μm square, and It is desirable that a metal sprayed layer is formed between the plate material and the composite coating film.
[0022]
  It is a coated body in which a metal sprayed layer is formed between the metal substrate and the composite coating film.
[0023]
A typical example of a roller to which the covering as described above is applied is an impression cylinder or an intermediate cylinder for an offset printing machine.
[0024]
    The above objectives are(A) Short-period irregularities that form a very sharp protrusion by spraying a porous ceramic sprayed layer having a porosity of 5 to 20% on a degreased and blasted metal roller substrate; Furthermore, a rough surface formed by combining long-period unevenness is formed, and the uneven surface layer of the porous ceramic and the inside of the hole are substantially entirely covered. A composite coating film coated with a low surface energy resin is formed so that the concave portion is thick, while the long-period convex portion is thinly adhered, and the surface property is long-period unevenness of ceramic spraying. An impression cylinder or an intermediate cylinder having a surface roughness Rmax of 20 to 40 μm so as to be maintained and having smooth irregularities, or (B) a degreased and blasted metal plate material A short-period unevenness that forms a very sharp protrusion by spraying a porous ceramic sprayed layer having a porosity of 5 to 20% on a substrate and a longer-period unevenness are combined. Further, a rough surface formed by the above method is formed, and the surface of the irregular surface of the porous ceramic and the inside of the hole are substantially entirely covered, but the long-period concave portion of the ceramic sprayed layer is thick, while the long-period convex portion is formed. A composite coating film in which a low surface energy resin is coated so as to be thinly adhered is formed on the part, and the surface texture generally maintains long-period irregularities of ceramic spraying so that the surface roughness Rmax 20 It is also achieved by a printing apparatus having an impression cylinder or an intermediate cylinder formed by winding a covering body having a smooth unevenness at ˜40 μm.
[0025]
The coated body of the present invention is preferable for a roller (low load portion) having a relatively low contact pressure between the printing paper surface and the roller, such as a feed cylinder (intermediate cylinder) of a sheet-fed printing press or a guide roller for a rotary printing press. A base layer formed by adhering a plurality of inorganic fine particles to a substrate made of a synthetic resin film or water-resistant treated paper, and a low surface energy resin formed on the surface of the base layer It is the coating body formed by forming the composite coating film which consists of a layer.
[0026]
In the coated body of the present invention, the fine particles are ceramic powder or glass beads, and the surface property of the coated body is a surface roughness R._maxIt is desirable that it is 20-150 micrometers and has a smooth unevenness | corrugation.
[0027]
Typical examples of the roller to which the covering as described above is applied include an intermediate cylinder for an offset printing machine, a guide roller for a rotary printing machine, and the like.
[0028]
Similarly, the present invention is a covering that is detachably wound over substantially the entire circumferential surface of a roller for treating a film-like body having a surface having an adhesion transfer substance applied thereto, similar to a printed matter in a printing press, A composite coating film comprising a hard base layer having fine irregularities on the surface and a silicone resin layer formed on the surface of the base layer without completely eliminating the irregularities is formed on the flexible substrate. It is characterized by that.
[0029]
The above-mentioned objects include: (A) a porous ceramic sprayed layer on a degreased and blasted metal roller base material, and a low surface energy resin layer formed on the surface of the ceramic sprayed layer and in the pores; A composite coating film is formed, and the surface property is surface roughness R_maxOn the impression cylinder or intermediate cylinder or (B) flexible substrate having a smooth unevenness of 20 to 40 μm, the hard base layer having fine unevenness on the surface and the unevenness on the surface of the base layer A composite coating film comprising a low surface energy resin layer formed without completely disappearing is formed, and the surface property is surface roughness R_maxA hard base layer having fine irregularities on the surface and a base on an impression cylinder or intermediate cylinder or (C) a flexible substrate formed by winding a covering having 20-40 μm and having smooth irregularities A composite coating film comprising a low surface energy resin layer formed without completely eliminating the unevenness is formed on the surface of the layer, and the surface property is surface roughness R_maxIt is also achieved by a printing apparatus having a guide roll or an intermediate cylinder formed by winding a covering having a smooth unevenness at 20 to 150 μm.
[0030]
The surface texture of the impression cylinder or intermediate cylinder is typically represented by the surface roughness R_maxIs preferably 20 to 40 μm, and has smooth unevenness. Furthermore, it is desirable that the uneven projections are uniformly dispersed at a rate of about 1 per 20 μm × 20 μm square to 100 μm × 100 μm square.
[0031]
In addition, a metal sprayed layer may be formed between the metal roller base material or the metal plate material and the composite coating film in order to bond the composite coating film more firmly. preferable.
[0032]
Further, the low surface energy resin is preferably a silicone resin.
[0033]
The above-mentioned objects include: (A) a porous ceramic sprayed layer on a degreased and blasted metal roller base material, and a low surface energy resin layer formed on the surface of the ceramic sprayed layer and in the pores; A composite coating film is formed, and the surface property is surface roughness R_maxOn the impression cylinder or intermediate cylinder or (B) flexible substrate having a smooth unevenness of 20 to 40 μm, the hard base layer having fine unevenness on the surface and the unevenness on the surface of the base layer A composite coating film comprising a low surface energy resin layer formed without completely disappearing is formed, and the surface property is surface roughness R_maxA hard base layer having fine irregularities on the surface and a base on an impression cylinder or intermediate cylinder or (C) a flexible substrate formed by winding a covering having 20-40 μm and having smooth irregularities A composite coating film comprising a low surface energy resin layer formed without completely eliminating the unevenness is formed on the surface of the layer, and the surface property is surface roughness R_maxBy a cleaning device in a printing apparatus, characterized in that a guide roll or intermediate cylinder, which is 20 to 150 μm and wound with a covering having smooth irregularities, is provided with a cleaning body that can be pressed and released. Is also achieved.
[0034]
The surface texture of the impression cylinder or intermediate cylinder used in the present invention is typically a surface roughness R._maxIs preferably 20 to 40 μm, and has smooth unevenness. Furthermore, it is desirable that the uneven projections are uniformly dispersed at a rate of about 1 per 20 μm × 20 μm square to 100 μm × 100 μm square.
[0035]
In addition, a metal sprayed layer may be formed between the metal roller base material or the metal plate material and the composite coating film in order to bond the composite coating film more firmly. preferable.
[0036]
Further, the low surface energy resin is preferably a silicone resin.
[0037]
In addition, such a composite coating does not have to be directly formed on the surface of the metal roller base material, but is configured as a detachable coating, and is wound around substantially the entire circumference of the roller for pressing and transferring the printing medium. It is good also as something to do.
[0038]
  The present invention is a cleaning device in an offset printing apparatus comprising the impression cylinder according to any one of the above, comprising a cleaning body that can be pressed and dissociated on a roller surface of a rubber cylinder facing the impression cylinder, And a sequence control mechanism that rotates the pressure drum in contact with the rubber cylinder for a certain period of time in a state in which the cleaning body is pressed against the rubber cylinder. It is also achieved by a cleaning device characterized in that it can be performed.
[0039]
In the covering according to the second aspect of the invention, the low surface energy resin layer is preferably made of a silicone resin.
[0040]
In addition, this covering can be roughly divided into two modes. One of them is preferably applied to a roller (high load portion) having a relatively high printing pressure, such as an impression cylinder for an offset printing machine, for example, from a metal plate that has been degreased and blasted. On a substrate formed by forming a composite coating film composed of a porous ceramic sprayed layer and a low surface energy resin layer formed on the surface of the ceramic sprayed layer and in the pores (hereinafter, This will be referred to as “the covering of the first embodiment”).
[0041]
The other is preferably applied to a roller (low load portion) having a relatively low contact pressure between the printing paper surface and the roller, such as a feed cylinder of a sheet-fed printing machine or a guide roller for a rotary printing machine. A composite coating film comprising a base layer formed by adhering a plurality of inorganic fine particles on a substrate made of a resin film or water-resistant treated paper and the like, and a low surface energy resin layer formed on the surface of the base layer It is a covering formed (hereinafter referred to as “the covering of the second embodiment”).
[0042]
In the covering of the first aspect, the surface property of the covering is a surface roughness R._maxIt is desirable that it has a smooth unevenness of 20 to 40 μm, and that the protrusions of the unevenness are present at a ratio of about 1 per 20 μm × 20 μm square to 100 μm × 100 μm square, and It is desirable that a metal sprayed layer is formed between the plate material and the composite coating film.
[0043]
In the covering of the second aspect, the fine particles are ceramic powder or glass beads, and the surface property of the covering is a surface roughness R._maxIt is desirable that it is 20-150 micrometers and has a smooth unevenness | corrugation.
[0044]
Typical examples of the roller to which the covering as described above is applied include an impression cylinder or intermediate cylinder for an offset printing machine, a guide roller for a rotary printing machine, and the like.
[0045]
The present invention is also a printing apparatus having the impression cylinder or the intermediate cylinder of the first invention. The present invention is also a printing apparatus including a printing medium pressure-bonding / transfer roller formed by winding the covering according to the second invention around an outer peripheral surface. The present invention further includes a pressure drum or an intermediate drum formed by winding the pressure drum or the intermediate drum according to the first invention or the covering according to the first aspect of the second invention on an outer peripheral surface in a high load portion. And it is also a printing apparatus which arrange | positions the intermediate | middle cylinder or guide roller which winds the coating | coated body which concerns on the 2nd aspect of the said 2nd invention on an outer peripheral surface in a low load part.
[0046]
The present invention also relates to a cleaning device in a printing apparatus comprising an impression cylinder or intermediate cylinder according to the first invention or an impression cylinder or intermediate cylinder formed by winding the covering of the second invention around an outer peripheral surface. The roller surface of the impression cylinder or the intermediate cylinder is provided with a cleanable body that can be pressed and released.
[0047]
The present invention also provides offset printing comprising the impression cylinder or intermediate cylinder of the first invention, or the impression cylinder configured as an impression cylinder or intermediate cylinder formed by winding the covering of the second invention on the outer peripheral surface. The cleaning device includes a cleaning body that can be pressed on a roller surface of a rubber cylinder facing the impression cylinder, and the pressure cylinder contacts the rubber cylinder for a predetermined time in a state where the cleaning body is pressed against the rubber cylinder. It has a sequence control mechanism that rotates, and is characterized in that the pressure cylinder can be cleaned together with the cleaning of the rubber cylinder.
[0048]
Further, the present invention is a roller for treating a film-like body having a surface having an adhesion transfer substance applied thereto, like a printed matter in a printing press, and is porous on the surface of a metal roller base material that has been degreased and blasted. A composite coating film comprising a ceramic sprayed layer and a silicone-based resin layer formed on the surface of the ceramic sprayed layer and in the hole is formed.
[0049]
Similarly, the present invention is a covering that is detachably wound over substantially the entire circumferential surface of a roller for treating a film-like body having a surface having an adhesion transfer substance applied thereto, similar to a printed matter in a printing press, A composite coating film comprising a hard base layer having fine irregularities on the surface and a silicone resin layer formed on the surface of the base layer without completely eliminating the irregularities is formed on the flexible substrate. It is characterized by that.
[0050]
As this covering, a porous ceramic sprayed layer as a base layer on a substrate made of a metal plate material that has been degreased and blasted, and a silicone-based resin layer formed on the surface of the ceramic sprayed layer and in the pores, A first layer comprising a composite coating film comprising: a base layer formed by adhering a plurality of inorganic fine particles on a substrate comprising a synthetic resin film or water-resistant treated paper; and the base layer The 2nd aspect which consists of the thing in which the composite coating film which consists of a silicone type resin layer formed on the surface of this is formed is contained.
[0051]
DETAILED DESCRIPTION OF THE INVENTION
As described above, the impression cylinder or the intermediate cylinder according to the present invention is formed on the surface of the porous ceramic sprayed layer, the surface of the ceramic sprayed layer, and in the hole portion on the surface of the metal roller base material that has been degreased and blasted. A composite coating film comprising a low surface energy resin layer is formed. FIG. 1 schematically shows a cross-sectional structure of an embodiment of the impression cylinder or intermediate cylinder according to the present invention, and FIG. 2 further enlarges the cross-sectional structure of the impression cylinder or intermediate cylinder according to the present invention. FIG. 3 schematically shows a cross-sectional structure in the manufacturing process of the impression cylinder or the intermediate cylinder according to the present invention. In these drawings, the vertical and horizontal scale ratios are exaggerated.
[0052]
In order to obtain an impression cylinder or an intermediate cylinder used in the present invention, first, a ceramic sprayed layer 12 is formed on the surface of a metal roller base 10 having a roughened surface by degreasing and blasting as shown in FIG. . In the example shown in this figure, a metal sprayed layer 11 is formed on the surface of the metal roller base material 10, and a ceramic sprayed layer 12 is formed thereon. The surface of the ceramic sprayed layer 12 formed in this way has short-period irregularities (pitch-like irregularities) that form very sharp protrusions as shown in the figure, and even longer-period irregularities (waviness-like irregularities). And a rough surface formed by combining with R, typically, preferably R_maxThe ceramic sprayed layer 12 has a rough surface of about 30 to 50 μm and is porous, and preferably has fine pores of 0.1 μm to several tens of μm with a porosity of 5 to 20%.
[0053]
Here, when the ceramic sprayed layer 12 is impregnated with a low surface energy resin such as a silicone resin and dried and solidified, for example, as shown in FIGS. A low surface energy resin layer 13 is formed in the portion. As described above, the low surface energy resin 13 has the adhesiveness to the ceramic sprayed layer 12 due to the anchor effect caused by entering the portions because the ceramic sprayed layer 12 has pitch-wave irregularities and is porous. The composite coating is well formed, and the composite coating 14 is constituted by the ceramic sprayed layer 12 and the low surface energy resin layer 13.
[0054]
Further, the low surface energy resin 13 substantially covers the entire surface of the ceramic sprayed layer 12, but is thick on the undulating undulations and thinly attached to the undulating undulations. For this reason, the surface texture is smoother than the state in which only the ceramic sprayed layer 12 is formed, but the unevenness caused by the ceramic sprayed layer 12 is not completely buried, and the undulating unevenness is generally maintained. A rough surface having smooth irregularities can be formed. The final surface roughness R_maxIs typically about 20 to 40 μm. Further, it is desirable that the convex portions in the final smooth unevenness (the convex portion of the swell) are uniformly dispersed at a ratio of about 1 per 30 μm × 30 μm square to 60 μm × 60 μm square, for example. The convex portion referred to here is measured by two-dimensionally scanning the surface of the object to be measured over a length of 20 mm × width of 20 mm, and has a height of 70% or more of the height of the highest convex portion in this measurement region. The convex part which has is pointed out.
[0055]
For this reason, when the impression cylinder or the intermediate cylinder according to the present invention is in contact with the printing medium, it contacts only the smooth protrusion as described above without contacting the entire roller surface, and the surface is low. Due to the presence of the surface energy resin, the transfer of ink from the substrate is unlikely to occur, and the transferred ink may have a smooth uneven profile because the surface is due to the low surface energy resin. Together, it can be easily removed by lightly touching with a dry cloth material or the like.
[0056]
In addition, as described above, since the low surface energy resin layer 13 is combined with the ceramic sprayed layer 12 and applied to the surface, even if it is used for an extremely long period of time, the entire surface is worn away. It does not occur, and only wear occurs at a very small portion, that is, the convex portion of the undulating unevenness. For this reason, the low surface energy of the roll surface is maintained over a long period of time, and the characteristics are hardly deteriorated. The undulations are expressed as “undulations” for comparison with the concavo-convexs of finer pitches. However, the undulations are not visible at all. Therefore, the resin layer 13 on the surface of the projections is not visible. Even if the ceramic sprayed layer 12 is exposed and the ink adheres and reversely shifts at this portion, there is no problem in print quality.
[0057]
In the present invention, as described above, not only the composite coating film is directly formed on the surface of the metal roller base material, but the roller can be detachably mounted on the roller body 20, for example, as shown in FIG. A structure having a covering 21 to be wound, and a metal spray layer 23 similar to the above, a ceramic spray layer 24 and a low surface energy resin layer 25 on a metal plate 22 as a base material of the cover 21. It is also possible to form a composite coating film 26 consisting of the following. In this case, the excellent action and effect can be obtained in the same manner as described above. Since only the covering 21 can be exchanged without exchanging, it is advantageous in terms of cost. In addition, in the aspect of forming the covering body 21 in this way, in order to increase the adhesion of the composite covering film 26 to the roller body 20 in consideration of the bending stress applied when the roller body 20 is mounted, The metal spray layer 23 is preferably formed as much as possible.
[0058]
Furthermore, in the case of a covering, an aspect different from that described above may be more preferable depending on the type of roller to be applied. That is, the roller to which the cover according to the first aspect of the second invention as described above, or the roller of the first invention is applied, has a very high ink adhesion preventing effect and high durability when used in an actual machine. Has practically very great value. However, when applied to the impression cylinder, intermediate cylinder, guide roller, etc. of an existing printing press, the work is complicated and the cost is high, such as replacement of the roller and modification of the plate detaching mechanism. It also has a side. In the case of the covering according to the first aspect of the second invention, a metal plate material is used as the base material. The metal plate material has vertical and horizontal dimensions, hole processing for mounting, bending according to the shape of the roller to be mounted. After processing or the like is performed in advance, it is necessary to perform ceramic spraying and low surface energy resin coating, which inevitably requires batch processing with a cut plate, resulting in high costs. And as a roller to which such a covering is applied, there are many low-load rollers that do not apply printing pressure.
[0059]
From such a viewpoint, as a coating material for a roller whose conditions such as printing pressure and friction are mainly low, for example, as shown in FIG. In addition, as a hard base layer replacing the ceramic sprayed layer 23, a composite coating formed by adhering a plurality of inorganic fine particles such as ceramic powder and glass beads and comprising the inorganic fine particle layer 33 and the low surface energy resin layer 34 is provided. The thing of the 2nd aspect formed with the membrane | film | coat 35 can be considered. In the figure, reference numeral 36 denotes an adhesive layer for attaching inorganic fine particles to the base material 32.
[0060]
In the case of the covering according to the second aspect, although it is inferior to the covering according to the first aspect in terms of durability, it can be easily cut to a desired size using a scissors, a cutter or the like, and is bent for winding. This is advantageous in terms of workability and cost.
[0061]
The cover according to the second aspect is particularly advantageous as a cover for a low-load roller as described above. Furthermore, there is another point to be noted. That is, in a conventional printing apparatus using, for example, a blasted chrome-plated roller or the like in a high load portion (for example, a chrome-plated roller as an impression cylinder of an offset printing machine), the roller is contaminated during operation of the printing apparatus. Remarkably, it is necessary to frequently stop the operation and perform manual cleaning of the roller, and the roller of the low load portion has not been a problem because it is also cleaned at this time. In the case of a printing apparatus using as a high load portion a roller formed by winding the roller according to the first aspect of the present invention or the cover according to the second aspect of the present invention, the following low load portion roller is chrome plated on a general iron roller. If a conventional coating body such as a glass bead coating body is pasted on these, the fouling frequency of the high load roller will be significantly reduced. Contamination of the low-load portion roller becomes a problem, and there is a situation in which the operation must be stopped for cleaning the low-load portion roller or replacing the adhered cover. In the printing apparatus having a configuration in which the roller for press-bonding / transferring the printing body of the invention or the roller around which the covering according to the first aspect of the second invention of the present application is wound is provided in the high load portion, It means that a printing apparatus having extremely excellent operability can be provided by winding the covering of the two aspects.
[0062]
As described above, the covering of the second invention was formed on a flexible substrate without causing the unevenness to completely disappear on the surface of the hard base layer having fine unevenness on the surface and the surface of the base layer. Widely included are those formed with a composite coating film comprising a low surface energy resin layer.
[0063]
In addition, as described above, the impression cylinder, the intermediate cylinder or the guide roller according to the present invention is extremely easy to remove the transferred and adhered ink. It is only necessary to provide a cleaning body such as a cloth material, and it can be made very compact, and can be sufficiently automatically cleaned by being incorporated in the printing apparatus. In particular, an impression cylinder is used in the printing apparatus. A pressure body is provided on the roller surface of the rubber cylinder facing the pressure cylinder, and the pressure cylinder is rotated in contact with the rubber cylinder for a predetermined time in a state in which the cleaning body is pressed against the rubber cylinder. Then, even if the impression cylinder is not directly equipped with a cleaning device, the ink stain attached to the impression cylinder can be transferred to the rubber cylinder side, and the impression cylinder can be cleaned together with the cleaning of the rubber cylinder. More effective in configuration It becomes as.
[0064]
Hereinafter, the present invention will be described in more detail based on embodiments.
[0065]
As the metal roller base material in the impression cylinder or the intermediate cylinder of the first invention, one made of cast iron, stainless steel, aluminum alloy pipes, cylinders or rolls from plate materials, etc. is appropriately selected according to the application. . For example, when the roller is an impression cylinder of an offset printing press, a pipe such as an aluminum alloy or iron is preferable when a cylinder such as FCD (ductile cast iron) is a guide roller of a rotary press. Of course, it is not limited to these.
[0066]
Such a metal roller base material needs to have a predetermined diameter accuracy by cutting or polishing first. That is, the impression cylinder or the intermediate cylinder roller used in the printing apparatus according to the present invention cannot perform such cutting and polishing as the final finish.
[0067]
And in order to improve adhesiveness with the ceramic sprayed layer formed in the upper part, the surface of a metal roller base material is degreased and blasted by a known method to roughen the surface.
[0068]
Next, if necessary, a metal or metal alloy such as Al, Ni, Cr or the like, preferably a spray layer such as Ni-Cr, is applied to the metal roller base material by a method such as plasma spraying, arc spraying, gas spraying, or the like. Form. This metal spray layer is intended to further improve the adhesion between the metal roller base material surface and the ceramic spray layer, and in particular for a roller that is subjected to a high load during use, such as an impression cylinder. It is highly desirable to form a metal sprayed layer, but it is possible to omit a roller such as a guide roller that does not require a relatively high load in consideration of economy and the like. Note that the thickness of the metal sprayed layer may be an average film thickness of about 30 to 70 μm. If the thickness is less than 30 μm, the adhesion improving effect due to the formation of the metal spray layer may not be obtained. On the other hand, if the thickness exceeds 70 μm, no further effect can be expected, which is economically disadvantageous.
[0069]
Next, a ceramic sprayed layer is formed on the surface of the metal roller substrate or the metal sprayed layer by using a known ceramic spraying method such as a plasma jet spraying method. As a ceramic material, Al₂O₃TiO₂, Al₂O₃-TiO₂, Cr₂O₃, ZrO₂, WC, WC-Co, Cr₃C₂Examples thereof include, but are not limited to, TiC and the like or a mixture thereof, as well as composite coatings and cermets which are obtained by simultaneously spraying ceramics and metal in order to provide conductivity. The ceramic material can be selected from adhesion strength with metal roller base material or sprayed metal, wear resistance, and fine ceramic pores (continuous pores) of several to several tens of micrometers. 20% and its surface roughness is R_maxWhat is necessary is just to carry out in consideration of economical efficiency, such as becoming 30-50 micrometers. Generally, white alumina (W-Al₂O₃) And gray alumina (G-Al₂O₃) (Al₂O₃-TiO₂), Chromia (Cr₂O₃) Is desirable.
[0070]
In addition, it is desirable that the ceramic sprayed layer has fine pores (continuous pores) of several μm to several tens of μm with a porosity of 5 to 20%. When the porosity is less than 5%, the surface active resin may not sufficiently enter the ceramic sprayed layer, and the peelability may be increased. On the other hand, the porosity exceeds 20%. This is because the strength of the ceramic sprayed layer that becomes the skeleton structure of the composite coating may be lowered. The surface roughness is R_maxIt is desirable to have about 30 to 50 μm when the low surface energy resin as described later is deposited on the surface of the ceramic sprayed layer, and the low surface energy resin stably adheres and is finally necessary. Moreover, this is because a sufficiently large smooth unevenness is easily formed.
[0071]
Further, the thickness of the ceramic sprayed layer is desirably about 30 to 200 μm, more preferably about 40 to 80 μm. That is, if the average film thickness is less than 30 μm, there is a possibility that a sprayed layer having uniform properties such as adhesion, strength and abrasion resistance cannot be obtained, while the average film thickness exceeds 200 μm. This is disadvantageous in terms of cost. Furthermore, in an embodiment where high diameter accuracy is required as in the case where the roll is an impression cylinder, the film thickness is desirably 150 μm or less. That is, in the case of the impression cylinder, it is necessary to suppress the final finishing diameter to D ± 0.02 mm or less and the cylindricity of 0.020 or less.
[0072]
The surface roughness of the ceramic sprayed layer is generally R as described above._maxAlthough it is desired to be about 30 to 50 μm, the optimum surface roughness required for the final product varies depending on the type of roller.
[0073]
When the ceramic sprayed layer is formed in this way, the low surface energy resin is impregnated and coated from the upper part by a method such as spraying, dipping, brushing, roller coating, etc., and dried and solidified at a predetermined temperature, A low surface energy resin layer is formed on the surface of the thermal spray layer and in the pores. The low surface energy resin is not particularly limited as long as it has a low wettability with respect to the ink used and can form a film that is stable against a chemical used in the ink composition, preferably a high hardness film. However, usually, a silicone resin and a fluorine atom-containing resin are desirable, and a silicone resin is more desirable in terms of its hardness, workability, chemical stability, and the like.
[0074]
Silicone resins have a skeletal structure mainly composed of Si-O-Si bonds and organic groups, preferably methyl groups and / or phenyl groups, and more preferably methyl groups, after polymerizing and three-dimensionally after construction. And what is necessary is just to be able to form a stable cured film. The more methyl groups as the side chain, the lower the wettability with respect to the ink. However, from the viewpoint of improving the hardness, it is possible to increase the content of the cross-linked structure due to functional groups such as phenyl groups or vinyl groups. desired.
[0075]
In addition, the form at the time of construction is not particularly limited, for example, liquids such as oligomers and monomers, or solutions in which a resinous material is dissolved in an appropriate solvent, such as silicone varnish and silicone rubber Various known compositions that are classified and marketed can be appropriately selected and used. For example, a composition marketed as a varnish-type silicone release agent, or a composition similar thereto is available. Many are preferable from the viewpoints of workability and obtained film properties. As the silicone release agent, for example, a silicone mold or copolymer having a structure represented by the general formula (I) as a main component can be obtained as a commercial product.
[0076]
[Chemical 1]

[0077]
(However, in the formula, each R independently represents a hydroxyl group, alkyl, aryl, alkenyl, halogen-substituted alkyl, halogen-substituted aryl, halogen-substituted alkenyl, preferably methyl group, and n is 1 to 30000.) The silicone resin composition to be used is not limited to such a silicone release agent.
[0078]
Further, in such a silicone-based resin composition, if necessary, a filler such as silica fine particles for increasing the film hardness can be blended. It is necessary to have a particle size that can penetrate sufficiently.
[0079]
In addition, as the fluorine atom-containing resin, a thermoplastic fluorine atom-containing resin such as polychlorotrifluoroethylene, polyvinylidene fluoride, polyvinyl fluoride or the like is used, which is applied after being suspended or swollen in an appropriate solvent and heated to a melting temperature or higher. It is also possible to use a dispersion processing method such as forming a film, but in order to form a film more reliably on the surface of the ceramic sprayed layer and in the pores, a small amount of hydroxyl groups and carboxylic acid groups are formed in the molecular chain. Thermosetting fluorine atom-containing resins that have functional groups such as, can be applied in liquid form, and are cured at room temperature or by crosslinking are desirable. For example, co-polymerization of fluoroethylene with acrylic acid and methacrylic acid Examples include coalescence.
[0080]
The thickness of the low surface energy resin layer to be formed on the surface of the ceramic sprayed layer is thicker on the wavy undulations of the ceramic sprayed layer as described above, while it is thinly attached to the wavy undulations of the ceramic sprayed layer. It is difficult to specify as However, it is desirable that the entire surface of the thermal spray layer be deposited at a thickness of about 0.5 to 20 μm so as to cover the entire surface substantially and maintain the undulations of the ceramic thermal spray layer.
[0081]
The impression cylinder or the intermediate cylinder of the present invention thus obtained has smooth surface irregularities in the final surface texture, and typically has a surface roughness R_maxIs preferably about 20 to 40 μm, and the smooth surface irregularities on the final surface are, for example, about 1 piece per 20 μm × 20 μm square to 100 μm × 100 μm square, more preferably 30 μm × 30 μm square It is desirable that they are uniformly dispersed at a rate of about one per 60 μm × 60 μm square. The entire surface is formed by a dense low surface energy resin layer held as a composite coating film on the ceramic sprayed layer, and has low wettability with respect to the ink used.
[0082]
For this reason, the roller of the present invention can be suitably used as various rollers disposed on an impression cylinder or an intermediate cylinder in various printing machines. Specifically, for example, an impression cylinder in an offset printing machine, or an offset rotary press (newspaper). It can be suitably used as a guide roller in various rotary presses such as rotary presses, commercial offset rotary presses, foam rotary presses, gravure printing presses, flexographic printing presses and letterpress rotary presses.
[0083]
Next, the covering of the second invention will be described in detail. The covering according to the second invention is formed on a flexible substrate with a hard base layer having fine irregularities on the surface and a low surface energy property formed on the surface of the base layer without completely eliminating the irregularities. A composite coating film composed of a resin layer is formed.
[0084]
When relatively stressing pressure resistance, durability, etc. as a flexible substrate, it is necessary to use a metal plate such as an aluminum alloy plate or stainless steel plate, and when emphasizing ease of construction, price, etc. These include shrinkage due to absorption of water, solvent, etc., small expansion and contraction due to heat, some degree of flexibility to adhere well to the roller surface, and some degree of tearing, strength to withstand tension, and cutter From the viewpoint of easy cutting with a knife, scissors or the like, the use of a synthetic resin film or water-resistant treated paper is exemplified, but it is of course not limited thereto. Synthetic resin films include olefin-based films such as polyethylene and polypropylene, polyurethane-based films, polyester-based films, polyvinyl chloride or polyvinylidene chloride-based films, polyamide-based films, etc., and water-resistant treated paper includes resin-impregnated paper. , Water-resistant kraft paper, or other water-resistant non-woven paper is included, but it is of course not limited thereto.
[0085]
The thickness of the flexible substrate depends on the type of plate material or the type of roller, and is not particularly limited, but is about 0.1 to 0.5 mm, for example. Can be used.
[0086]
Examples of such a hard base layer having fine irregularities on the surface formed on the flexible substrate include a ceramic sprayed layer as described above or a coating layer formed of a plurality of inorganic fine particles. Further, as the low surface energy resin layer formed on the surface of the base layer without completely eliminating the unevenness, the above-described silicone resin or the like is used.
[0087]
Here, when a metal plate material is used as the flexible substrate and a ceramic sprayed layer is used as the hard base layer (first embodiment), the case relating to the roller of the first aspect of the invention and the metal product to be constructed are used. Since the roller base material is merely replaced with a metal plate material, the manufacturing method, manufacturing conditions, material and characteristic values of each layer are substantially the same, and detailed description thereof will be omitted. To outline only the manufacturing method, a metal plate material is first degreased and blasted by a well-known method to roughen the surface, and then a metal or metal alloy sprayed layer is formed as necessary. By using the ceramic spraying method, a ceramic sprayed layer is formed, and a low surface energy resin is impregnated and coated from the upper part, dried and solidified at a predetermined temperature, and a low surface is formed on the surface of the ceramic sprayed layer and in the pores. An energetic resin layer is formed to form a composite coating film layer.
[0088]
Next, the case where an inorganic fine particle layer is formed as a hard base layer will be described. As the inorganic fine particles to be used, various ceramic powders, glass beads, hard metal particles and the like are used, and various ceramic powders and glass beads are preferable. The size of these fine particles is not particularly limited, but those having an average particle size of about 30 to 200 μm and having a narrow particle size distribution are preferable, and the shape thereof is spherical or spherical. Is preferably from the viewpoint of not damaging the printing paper and the printing surface. These fine particles may be porous or substantially nonporous. In the case of a porous material, the adhesion of a low surface energy resin to be described later is good, but on the other hand, it is often weak in strength and expensive in price. In the case of a non-porous material, the adhesion of the low surface energy resin is reduced, but it is advantageous in terms of strength and price. Therefore, what is necessary is just to select suitably whether it is a porous thing or a non-porous according to the use conditions etc. of the roller in which the said covering body is constructed.
[0089]
In general, an adhesive is used to adhere such inorganic fine particles to a flexible substrate, in particular, a top of a substrate such as a synthetic resin film or water-resistant treated paper. The adhesive used has sufficient water resistance and solvent resistance, and has good adherence or wettability with the substrate and inorganic fine particles used and the low surface energy resin applied to the upper part. A thing is appropriately selected and used. Although not particularly limited, for example, acrylic adhesive, epoxy adhesive, chloroprene adhesive, cyanoacrylate adhesive, urethane adhesive, SBR adhesive, butyl rubber adhesive, SBS / SIS adhesive An adhesive or the like can be used. Further, when the base material is a thermoplastic synthetic resin film, a mode of direct adhesion by thermal welding of inorganic fine particles (partial melting of the synthetic resin film) is also conceivable.
[0090]
When such inorganic fine particles are attached to the upper part of the substrate, the surface roughness after the attachment is an appropriate value, for example, R_maxIt is necessary to make it adhere in the state which the head of an inorganic fine particle exposes so that it may become 30-150 micrometers. That is, if the inorganic fine particles are completely buried in the adhesive layer or the like, the function as a covering for imparting a rough surface to the roller cannot be achieved. In addition, the inorganic fine particles adhered on the base material may be in a state of being laminated in two layers or more as long as they are uniformly adhered to the whole, but only one layer as shown in FIG. This is more preferable because it is less likely to cause defects such as peeling of fine particles and exhibits stable characteristics.
[0091]
After the inorganic fine particle layer is formed in this manner, a low surface energy resin layer is formed on the upper part of the inorganic fine particle layer by using a silicone resin or the like in the same manner as described above to obtain a composite coating film. The thickness of the low-energy resin layer on the inorganic fine particle layer is thin on the exposed head of the inorganic fine particles, while it is relatively thick on the valley formed between the particles. It is necessary to have a state in which smooth irregularities are left without completely eliminating the irregularities formed in the valleys. For example, it is desirable that the inorganic fine particles be attached to the head portion with a thickness of about 2 μm and to the valley portion with a thickness of about 5 to 10 μm. In addition, the kind of specific low energy resin, its application | coating method, etc. are the same as that of the above. In order to improve the adherence between the low-energy resin and the inorganic fine particles (and the adhesive or base material partially exposed as the valleys), for example, chemical pretreatment using a known coupling agent or the like Various physical pretreatments can also be performed.
[0092]
The covering according to the second aspect of the second invention thus obtained also has smooth irregularities in the final surface properties, but the surface roughness R_maxIs preferably about 20 to 150 μm.
[0093]
In the case of the covering according to the second aspect of the second aspect of the present invention, a synthetic resin film or water-resistant treated paper can be used as the base material. For example, for a long base material wound in a roll shape, It can be said that inorganic fine particle coating and low energy resin coating are performed, and high production efficiency can be achieved. Then, it can be easily cut and applied to a necessary size for each of the pressure cylinder, intermediate cylinder, guide roller and the like to be wound.
[0094]
As a method of attaching the covering of the second invention to the roller body, a method using screwing or adhesion, or a method in which the roller body is provided with a clamping device or a winding device having a winding shaft can be employed. In the case of the covering according to the second embodiment, it can be easily attached using a double-sided adhesive tape or the like.
[0095]
The above-described roller according to the first invention or the roller wound with the covering according to the second invention or the structure of the covering are not limited to the field of printing presses, but also in the printed matter as described above. As with ink, a roller for treating a film-like body to which an adhesive migrating substance has been applied to the surface or its surface coating is similarly resistant to contamination of the roller by the adhesive migrating substance and has a high durability. It is clear that it can be suitably used as. Examples of applications other than the impression cylinder, intermediate cylinder, or guide roller in a printing machine include, for example, rollers in a pressure-bonding / transfer system of a printing object in various copying machines, but of course, the invention is not limited thereto. Absent.
[0096]
Further, in the printing press using the impression cylinder or the intermediate cylinder formed by winding the pressure cylinder or the intermediate cylinder of the first invention or the cover of the second invention, a cleaning device for these impression cylinders or the intermediate cylinder is provided. It is preferable to have. Such a cleaning device only needs to have a cleaning body that can come into contact with the surface of the impression cylinder or the intermediate cylinder in a portion that does not interfere with the transfer path of the printing medium or other apparatus configuration. The cleaning body may be configured to be in contact with the roller surface only at the end of printing, or may be configured to be appropriately contacted / separated during printing work. The cleansing body can provide a sufficient cleaning effect even if it is dry, but in order to obtain a higher cleaning effect, a wet body impregnated with a solvent is desired. In addition, a cleaning body can be comprised with flexible and absorptive materials, such as felt, a nonwoven fabric, a cloth material, and a paper material. Further, it is possible to adopt a configuration in which the roller surface is fixedly contacted or rotationally contacted.
[0097]
In particular, in the case of a printing press with a lot of printing such as a newspaper rotary press, cleaning of the guide roller in the middle of the lot is conventionally indispensable, and the main guide roller has been equipped with a cleaning device (wet). By using the guide roller according to the present invention, it is not necessary to clean the roller in the middle of the lot, and even a slight ink stain on the roller at the end of the operation can be obtained by cleaning the cleaning body of the cleaning device having the simple structure as described above. A necessary and sufficient cleaning effect can be obtained by a simple operation of lightly pressing on the surface and wiping. In the case of a newspaper rotary press or the like, the cleaning operation can also be performed by emptying the paper, making the rotation speed of the roller faster or slower than the paper feed speed, and slipping the roller surface and the paper surface. it can. Conventionally, in a newspaper rotary press, a cleaning operation is performed by applying a solvent to the roller surface and dissolving the ink on the roller surface, and then performing such a slip. However, the roller of the present invention is used. In such a case, a sufficient cleaning effect can be obtained only by slipping dry without using a solvent.
[0098]
Furthermore, the cleaning mechanism for the impression cylinder of the offset printing machine can have a simpler configuration. That is, as an impression cylinder cleaning device in an offset printing press using an impression cylinder according to the present invention, a cleaning body that can be pressed against a roller surface of a rubber cylinder facing the impression cylinder is provided, and the cleaning body is converted into a rubber cylinder. It may have a sequence control mechanism that rotates the pressure drum in contact with the rubber drum for a certain time in the pressed state. With such a configuration, at the end of the printing operation, the cleaning body is pressed against the roller surface of the rubber cylinder, and the contact between the rubber cylinder and the impression cylinder is turned on while the rubber cylinder is rotating. This is because if the pressure cylinder is rotated together with the rubber cylinder, the ink stain on the impression cylinder is reversely transferred onto the rubber cylinder and can be wiped off as a dirt on the rubber cylinder with a clean body.
[0099]
【Example】
Hereinafter, the present invention will be described more specifically with reference to examples.
[0100]
Reference example 1
The surface of a metal plate made of SUS304 having a thickness of 0.3 mm was roughened by degreasing and blasting. In this case, the surface roughness R_maxWas about 10 μm.
[0101]
Thereafter, a Ni—Cr alloy having a powder particle size of 10 to 55 μm is used, and a Ni—Cr sprayed layer having a film thickness of about 30 μm is formed on the cylinder surface by plasma spraying, followed by G-Al having a powder particle size of 10 to 44 μm.₂O₃The ceramic sprayed layer having a film thickness of about 70 μm was formed by plasma spraying in the same manner. Surface roughness R of this ceramic sprayed layer_maxWas about 40 μm, and as shown in FIG. 2, it was a rough surface wavy with very sharp protrusions. The ceramic sprayed layer had pores with a size of 0.1 to several tens of micrometers, and the porosity was about 16%. The coated body thus obtained was wound around the surface of a ductile cast iron metal cylinder to obtain an impression cylinder. This impression cylinder was subjected to the following printing test.
[0102]
Example 1
After performing the same procedure as in Reference Example 1, 100 parts of a silicone-based resin release agent (KS776L manufactured by Shin-Etsu Chemical Co., Ltd.), 300 parts of toluene and a curing catalyst (Shin-Etsu Chemical ( A solution obtained by mixing and stirring 1 part of CAT-PL8 manufactured by Co., Ltd. was impregnated and applied by a spray method, and then dried and solidified in a drying furnace at 150 ° C. for 1 hour to form a silicone resin film on the surface of the ceramic sprayed layer. This silicone-based resin film completely closes the communicating pores of the ceramic sprayed layer, and on the surface of the sprayed layer, it adheres thickly to the concave portions of the wavy undulations and thinly covers the convex portions and completely covers the entire surface. The film thickness was in the range of 2 to 20 μm although it varied depending on each part. And the surface roughness R after this silicone resin film formation_maxWas about 30 μm, and was a rough surface having smooth irregularities as shown in FIG. 1 or FIG. The impression cylinder thus obtained was subjected to the following printing test in the same manner as in Reference Example 1 and further to the following scratch resistance test.
[0103]
Printing test 1
The impression cylinder created in Reference Example 1 and Example 1 above is attached to an offset printing machine (manufactured by Komori Corporation, Kikuzen Duplex Machine), and red ink (manufactured by Toyo Ink Co., Ltd., High Plus) is used. Thus, double-sided printing was performed on 30,000 coated papers. For comparison purposes, a similar printing test was also performed using an ordinary impression cylinder polished after chromium plating. As a result, when the impression cylinder of Reference Example 1 was used, the ink stain on the impression cylinder surface compared to a normal chrome-plated impression cylinder because the impression cylinder surface had a grainy uneven shape. Although the number of paper passes increases, the stains become more and more serious, and when it exceeds about 3000 sheets, the back stain of the printed matter due to the ink stain on the impression cylinder becomes noticeable, and it turns out that it cannot be used practically. did. In addition, by removing the ink on the solid part of the printed matter with the sharp protrusions on the surface of the ceramic sprayed layer, countless fine voids (white spots) of several μm can be obtained, and the clearness of the printing is clearly visible even visually. It was inferior.
[0104]
On the other hand, in the case of the impression cylinder of Example 1, even after printing 30,000 sheets, only a very small amount of ink is adhered to the fine convex portions on the impression cylinder surface. Further, even if the number of sheets passed through was increased, there was almost no change and the ink adhesion did not grow. Furthermore, ink is hardly transferred to the protrusions on the surface of the impression cylinder even at the part that contacts the solid part of the printed matter, and the amount of missing ink is very small and small, so that there is almost no obstacle to the print quality of the printed matter. Good prints could be obtained.
[0105]
Further, after the printing test was completed, an attempt was made to remove the ink adhering to the surface of the impression cylinder. In the case of Example 1, the ink slightly adhered could be completely removed by lightly wiping with a dry cloth. In the case of the control chrome-plated impression cylinder, it is difficult to remove it by such treatment, and it cannot be removed unless it is washed with white kerosene. Even if an organic solvent is used, the ink that has entered the fine recesses on the surface cannot be completely removed, and the ink that has dissolved in the solvent and has flowed into the pores is difficult to clean. It was.
[0106]
Scratch resistance test
When the surface hardness of the impression cylinder obtained in Example 1 was examined by a pencil hardness test, it was 4H, and even if the iron tool (driver) was strongly pressed and rubbed, it was once a metal color on the impression cylinder. There was a scar mark, but this trace disappeared cleanly when I wiped it with a fingertip. That is, the surface of the impression cylinder in Example 1 was not scratched, but the tool was shaved and the wrinkles adhered to the impression cylinder. This means that only the fine projections on the surface of the impression cylinder are in contact with the tool, and this projection has an extremely thin silicone-based resin film on the ceramic sprayed layer with high wear resistance. This is considered to be because the influence of the hardness of the sprayed layer is strongly generated. In this projection, the silicone-based resin film is in direct contact with the tool, but it is only in contact as a very fine point and not as a surface. The silicone resin film is only worn and removed only at the protrusions, and the silicone resin film is not peeled off as a surface.
[0107]
On the other hand, for comparison, the silicone resin used in Example 1 or some silicone resins disclosed in Japanese Patent Application Laid-Open No. 62-94392 are applied to the cast iron cylinder surface having a smooth surface property before blasting. When the surface hardness of the test body obtained by direct coating was examined by a pencil hardness test, it was B to 2H, and it was easily scratched only by lightly rubbing with a hard tool or the like.
[0108]
Reference example 2
The surface of the roller made of an aluminum alloy pipe was degreased and blasted to roughen the surface. In this case, the surface roughness R_maxWas about 35 μm. Thereafter, a Ni—Cr alloy having a powder particle size of 10 to 55 μm is used, and a Ni—Cr sprayed layer having a film thickness of about 30 μm is formed on the cylinder surface by plasma spraying, followed by G-Al having a powder particle size of 10 to 44 μm.₂O₃The ceramic sprayed layer having a film thickness of about 70 μm was formed by plasma spraying in the same manner. Surface roughness R of this ceramic sprayed layer_maxWas about 40 μm, and was a rough surface wavy with very sharp protrusions as shown in FIG. The ceramic sprayed layer had pores with a size of 0.1 to several tens of micrometers, and the porosity was about 16%. The guide roller thus obtained was subjected to the following printing test.
[0109]
Example 2
After performing the same procedure as in Reference Example 2, 100 parts of a silicone-based resin release agent (KS776L manufactured by Shin-Etsu Chemical Co., Ltd.), 300 parts of toluene and a curing catalyst (Shin-Etsu Chemical ( A solution obtained by mixing and stirring 1 part of CAT-PL8 manufactured by Co., Ltd. was impregnated and applied by a spray method, and then dried and solidified in a drying furnace at 150 ° C. for 1 hour to form a silicone resin film on the surface of the ceramic sprayed layer. This silicone-based resin film completely closes the communicating pores of the ceramic sprayed layer, and on the surface of the sprayed layer, it adheres thickly to the concave portions of the wavy corrugations and thinly covers the convex portions, and completely covers the entire surface. The film thickness was in the range of 2 to 20 μm although it varied depending on each part. And the surface roughness R after this silicone resin film formation_maxWas about 30 μm, and was a rough surface having smooth irregularities as shown in FIG. The guide roller thus obtained was subjected to the following printing test in the same manner as in Reference Example 2.
[0110]
Printing test 2
The guide rollers created in Reference Example 2 and Example 2 above are each mounted on a foam press (MVF18, manufactured by Miyakoshi Co., Ltd.), and color pictures are printed with black, indigo, red and yellow process inks. On the other hand, continuous 40 hours were performed. For comparison, a similar printing test was also performed using a knurled roll with a normal aluminum alloy roll as a guide roller.
[0111]
As a result, when the guide roller of Reference Example 2 was used, good slip resistance was obtained, and the surface was a grainy uneven shape, so that a comparative knurled aluminum alloy guide was used. Compared with the roller, the ink stain was less and the cleaning frequency was about 1/2. However, as the number of papers passed increased, the stain became more serious, and when it exceeded about 10 hours, it was caused by the ink stain on this guide roller. As a result, it was found that the printed matter was noticeably soiled and could not be used practically.
[0112]
On the other hand, in the case of the guide roller of Example 2, even after 40 hours of printing, only a very small amount of ink adheres to the fine convex portions on the surface. Even if the number of sheets was increased, there was almost no change and the ink adhesion did not grow. For this reason, the stain of the printed matter that can be confirmed with the naked eye does not occur even after 40 hours of continuous operation, and a printed matter with good print quality can be obtained without cleaning the guide roller in the middle.
[0113]
In addition, after the printing test was completed, an attempt was made to remove the ink adhering to the surface of the guide roller. In the case of Example 1, the ink slightly adhering to the inside of the printing apparatus could be completely removed by simply wiping with a dry cloth. It was suggested that a dry type cleaning device for the guide roller provided in the above is sufficient. On the other hand, in the case of the comparative control, it is difficult to remove by such treatment, and it cannot be removed without washing with white kerosene, and the cleaning device provided in the printing apparatus also uses an organic solvent. It was confirmed that a wet cleaning device was necessary. Further, in the case of the guide roller of Reference Example 2, when washing is performed using such an organic solvent, the ink that has dissolved in the solvent and has flowed infiltrates into the pores, so that the cleaning is very difficult to perform. It was concluded that a sufficient cleaning effect could not be obtained even with a conventional wet cleaning apparatus using an organic solvent.
[0114]
Example 3
A low surface energy resin film is mixed and stirred with 100 parts of a silicone-based resin release agent (KNS316 manufactured by Shin-Etsu Chemical Co., Ltd.), 100 parts of toluene and 3 parts of a curing catalyst (CAT-PL56 manufactured by Shin-Etsu Chemical Co., Ltd.). An impression cylinder was produced in the same manner as in Example 1 except that it was formed using the prepared solution, and a printing test and a scratch resistance test were conducted in the same manner as described above. As a result, excellent results were obtained as in Example 1.
[0115]
Examples 4-7
KR2046 (Example 4), X-40-2141 (Example 5), X-41-9710H (Example 6) or X-40-201 (Example) 7) Except for using 7 (made by Shin-Etsu Chemical Co., Ltd.), an impression cylinder was prepared in the same manner as in Example 1, and a printing test was performed in the same manner as described above. Although there was a slight difference in the degree of soiling on the impression cylinder surface after the printing test, good printing quality was maintained as in Example 1 and the impression cylinder after completion of printing. The soil was completely removable by a dry method.
[0116]
Reference example 3
A test piece was prepared by coating a synthetic resin film (polypropylene) having a thickness of 100 μm with a silicone resin release agent (KNS316, manufactured by Shin-Etsu Chemical Co., Ltd.) to a thickness of 3 μm.
[0117]
Reference example 4
A glass bead having an average particle diameter of 200 μm is bonded to the same synthetic resin film as in Reference Example 3 with an adhesive (acrylic) so that the glass bead covers the entire surface of the film and the glass bead is evenly dispersed. Produced. The surface roughness of the obtained test piece is R_max140 μm.
[0118]
Example 8
After the glass beads were adhered to the film surface by the same method as in Reference Example 4, the same silicone release agent as used in Reference Example 3 was coated from the top of the glass bead layer. Silicone mold release agent is relatively thin, about 2 μm at the head of the glass beads, while it is relatively thick, about 5-10 μm, at the valley between the glass beads. R_maxIt was 133 μm.
[0119]
The test pieces of Reference Examples 3 and 4 and Example 8 thus obtained were subjected to the following gum tape peeling test and printing test.
[0120]
Gum Tape Peeling Test In order to confirm the adhesion of the test piece surfaces of Reference Examples 3, 4 and Example 8, a commercially available gum tape (width 25 mm × length 100 mm) was attached to the test piece surface and peeled off. The required force was measured.
[0121]
As a result, in the initial stage, Example 8 and Reference Example 3 were in a state where the gum tape hardly adhered (peeling force less than 5 g), but Reference Example 4 required a force of 110 g. The peel strength of the comparative polypropylene resin film itself was 480 g.
[0122]
Next, in order to examine the change with time of the peeling force due to surface wear, each test piece was attached to a roll having a diameter of 100 mm with a double-sided adhesive tape so that the silicone resin layer or the glass bead layer faced the surface side. The coated paper was attached with a winding angle of 90 ° and a tension force of 200 g / cm, the coated paper side was fixed, and the roller was rotated to perform a sliding wear test. In addition, the paper which apply | coated the ink regularly was used for the coated paper surface. And the above-mentioned gum tape peeling test was implemented for every predetermined rotation speed. FIG. 10 shows the relationship between the cumulative number of rotations obtained for each test piece and the peel force.
[0123]
As is clear from the results shown in FIG. 10, the test piece of Reference Example 3 has significantly less peeling force than that of Reference Example 4 while the silicone-based resin release agent is present on the surface, but the cumulative rotation is small. The number of release agents (about 1000 revolutions) wears off and the release force increases rapidly (that is, the stain resistance decreases). In addition, the reference example 4 has an effect of forming an uneven surface with glass beads in the initial stage compared to the resin film only as a comparison, and the peel force is small, but the cumulative rotational speed is large. As a result, ink and paper powder adhere to and accumulate on the concave surface, and the peeling force increases (decrease in stain resistance). On the other hand, in the case of Example 8, when the peel force is almost zero in the initial stage, the peel force increases slightly as the cumulative rotational speed increases, but the increase is very gradual, and the anti-contamination performance over a long period of time. To maintain. This is because the release of the release agent is only the convex part of the glass beads, and the release agent in the concave part is not worn off and remains as it is, so that ink and paper powder do not adhere and accumulate in the concave part. It seems that this does not lead to a decrease in the anti-contamination performance as in the case of.
[0124]
Printing test 3
The test pieces prepared in Reference Examples 3 and 4 and Example 8 were wound on the intermediate cylinder of a JP-40 double-sided printing machine manufactured by Akiyama Printing Co., Ltd. using double-sided adhesive tape and operated on the actual machine. A comparative test was performed. The paper used was coated paper, the ink was made by Toyo Ink Co., Ltd., High Plus, and the plate was printed on a test plate with a pattern with many solid parts.
[0125]
As a result, when the sample of Reference Example 3 was used, the surface was naturally high in ink repellency at the initial stage, but because of the high friction coefficient of the surface, the paper separation between the intermediate cylinder surface and the paper surface was very good. Absent. For this reason, when paper is transferred from the first intermediate cylinder to the second intermediate cylinder to the impression cylinder, a slight misalignment occurs between the intermediate cylinder and the paper. The print surface was scratched and smudged. In addition, with this test piece, the surface silicone release agent layer was worn and dropped as the number of printed copies increased, and the ink adhesion to the sheet surface suddenly increased in about one month, and the scratches and smudges on the printed matter were also extremely high. It became conspicuous and did not endure practical use.
[0126]
Moreover, when the thing of the reference example 4 is used, since an intermediate | middle cylinder becomes considerably dirty by printing about 5000-10000 sheets, and this becomes a double of a printed matter and dirt, it is impossible to operate a long-lasting printing press continuously, It is necessary to stop the machine and clean it with gasoline. This test piece is effective in terms of reducing the friction with the paper because the contact with the printing surface is a point contact, but the glass beads themselves have almost no ink repellency, especially the ink deposited and deposited in the recesses.・ Contaminants such as paper dust are very difficult to clean. The time and labor required for these cleaning removals accounted for a large proportion of the printing process. Also, dirt that could not be removed by each washing was accumulated in the recesses and the ink repellency was further lowered, so that a new sheet had to be replaced in 1 to 3 months. Further, deterioration of the sheet due to the solvent used for cleaning was a matter that cannot be ignored.
[0127]
On the other hand, when the sample of Example 8 was used, the stain on the intermediate cylinder surface was very small, and even with continuous printing of 60,000 sheets per day, the printed matter was not stained or doubled due to the intermediate cylinder stain. Slightly adhering ink stains could be easily removed by wiping with a cloth soaked in cleaning oil, and the residue on the recesses was very small. In other words, there is a great effect in reducing the occurrence of defective prints due to smearing of the intermediate cylinder, improving productivity by reducing the frequency of washing, and reducing the work load. It has become possible.
[0128]
【The invention's effect】
As described above, the printing-material pressure-bonding / transfer roller of the present invention and the printed-material pressure-bonding / transfer roller wound with the covering of the present invention have fine and relatively smooth irregularities on the surface properties. The surface of the substrate is coated with a composite coating consisting of a ceramic sprayed layer with excellent wear resistance or an inorganic fine particle layer and a low surface energy resin layer such as a silicone resin having a low surface energy. Therefore, it is difficult for ink to adhere to the surface. For this reason, various rollers disposed in the press-bonding / transfer system of the printing medium in various printing presses, for example, an impression cylinder in an offset printing press, or an offset rotary press (news rotary press, commercial offset rotary press, foam rotary press) It can be suitably used as a guide roller in various rotary presses such as gravure printing machines, flexographic printing machines, etc., and it is not necessary to perform a washing operation when performing a printing operation for a large amount or a long time continuously. It is possible to provide a printed matter having a good print quality and excellent durability. Furthermore, since the ink adhering to the surface can be easily removed by a dry method, the cleaning operation of the roller, which has been extremely dangerous and heavy labor in the past, becomes extremely easy and has a very simple configuration. By incorporating the cleaning device into the device, it is possible to automatically clean the device, and it is very effective in reducing the time and labor required for cleaning and the initial cost. Further, for example, in business form rotary presses, UV ink has been used in order to eliminate the problem of reverse transfer. However, by using the guide roller of the present invention, the ink itself is expensive. In addition, it is possible to achieve the same printing level with ordinary ink without using UV ink, which is complicated and expensive.
[0129]
Further, in the coated body of the present invention, in a mode in which a synthetic resin film or water-resistant treated paper is used as a base material, the non-printed body crimping / transfer roller of various sizes of an existing various printing machine is excellent in productivity. However, it can be easily cut and wound into an arbitrary size, and its application range is very wide.
[0130]
Furthermore, the roller having such a configuration has the same excellent effect not only in the field of printing presses but also in various fields in other fields for processing a film-like body to which an adhesion transfer substance is applied. It is what you play.
[Brief description of the drawings]
FIG. 1 is a diagram schematically showing a cross-sectional structure in one embodiment of a pressure drum or intermediate drum covering according to the present invention;
FIG. 2 is a diagram schematically showing an enlarged cross-sectional structure of an impression cylinder or intermediate cylinder covering according to the present invention;
FIG. 3 is a diagram schematically showing a cross-sectional structure in the manufacturing process of an impression cylinder or intermediate cylinder covering according to the present invention;
FIG. 4 is a cross-sectional view schematically showing a state in which the first embodiment of the pressure drum or intermediate drum covering according to the present invention is wound around a printing-material press-fitting / transfer roller;
FIG. 5 is a diagram schematically showing a cross-sectional structure of a second embodiment of the intermediate cylinder or guide roller covering according to the present invention;
FIG. 6 is a diagram showing a schematic configuration of a printing mechanism in an offset printing machine;
FIG. 7 is a schematic diagram for explaining ink stains on the impression cylinder during double-sided printing in offset printing;
FIGS. 8A and 8B are diagrams illustrating a relationship between an impression cylinder and a rubber cylinder and a printing medium in an offset printing machine, in which FIG. 8A illustrates a state where printing is performed on a narrow printing medium, and FIG. Figures showing the state of printing on the body,
FIG. 9 is a diagram showing a schematic configuration of a printing and transfer mechanism for a printing medium in another offset printing press (rotary press);
FIG. 10 is a graph showing the change over time in the adhesion characteristics of various coated surfaces obtained in the examples of the present invention.
[Explanation of symbols]
1 ... plate cylinder,
2 ... Rubber body,
3 ... impression cylinder,
4 ... Substrate,
5 ... Ink image,
6, 8 ... transfer ink image,
7 ... Guide roller
10, 22 ... metal roller base material,
11, 23 ... Metal sprayed layer,
12, 24 ... Ceramic sprayed layer,
13, 25, 34 ... low surface energy resin layer,
14, 26, 35 ... composite coating film,
20 ... Roller body,
21 ... covered body,
32 ... Base material (synthetic resin film or water-resistant treated paper),
33 ... inorganic fine particle layer,
36: Adhesive layer.

Claims (9)

  In a printing apparatus, a cover that is detachably wound over substantially the entire circumferential surface of an impression cylinder or an intermediate cylinder that is arranged in a pressure-bonding / transfer system for a printing medium that is bonded to the printing element and then transferred to the printing element. This is a short periodical method in which a porous ceramic sprayed layer having a porosity of 5 to 20% is sprayed on a substrate made of a metal plate material that has been degreased and blasted to form very sharp protrusions. A rough surface formed by combining unevenness and a longer period unevenness is formed, and the uneven surface layer of the porous ceramic and the inside of the hole are substantially entirely covered. A composite coating film coated with a low surface energy resin is formed so that it is thick on the periodic recesses, while thinly attached to the long-period projections, and the surface properties are long-period of ceramic spraying. Na Convex and generally in surface roughness Rmax 20 to 40 [mu] m so as to maintain the impression cylinder or transfer cylinder covering element, characterized in that those having a smooth irregularities.   The covering according to claim 1, wherein the low surface energy resin is a silicone-based resin. The covering according to claim 1 or 2, wherein the long-period uneven projections are present at a rate of about 1 per 20 µm × 20 µm square to 100 µm × 100 µm square.   The coated body according to claim 1, wherein a metal sprayed layer is formed between the metal substrate and the composite coating film.   (A) Short-period irregularities that form a very sharp protrusion by spraying a porous ceramic sprayed layer having a porosity of 5 to 20% on a degreased and blasted metal roller substrate; Furthermore, a rough surface formed by combining long-period unevenness is formed, and the uneven surface layer of the porous ceramic and the inside of the hole are substantially entirely covered. A composite coating film coated with a low surface energy resin is formed so that the concave portion is thick, while the long-period convex portion is thinly adhered, and the surface property is long-period unevenness of ceramic spraying. An impression cylinder or an intermediate cylinder having a surface roughness Rmax of 20 to 40 μm so as to be maintained and having smooth irregularities, or (B) a degreased and blasted metal plate material A short period unevenness which forms a very sharp protrusion by spraying a porous ceramic sprayed layer having a porosity of 5 to 20% on a substrate made of the above, and an even longer period unevenness are combined. Further, a rough surface formed by the above method is formed, and the surface of the irregular surface of the porous ceramic and the inside of the hole are substantially entirely covered, but the long-period concave portion of the ceramic sprayed layer is thick, while the long-period convex portion is formed. A composite coating film in which a low surface energy resin is coated so as to be thinly adhered is formed on the part, and the surface texture generally maintains long-period irregularities of ceramic spraying so that the surface roughness Rmax 20 A printing apparatus having an impression cylinder or an intermediate cylinder on which a covering body having a smooth unevenness is wound with a thickness of ˜40 μm. The long convex portion of the periodic roughness is, 20 [mu] m × 20 [mu] m square to the printing apparatus according to claim 5 being present in a ratio of about 1 pc in 100 [mu] m × 100 [mu] m square per.   The printing apparatus according to claim 5 or 6, wherein a metal sprayed layer is formed between the metal roller base material or the metal substrate and the composite coating film.   The printing apparatus according to claim 5, wherein the low surface energy resin is a silicone-based resin.   A cleaning device for an offset printing apparatus comprising the impression cylinder according to any one of claims 5 to 8, comprising a cleaning body that can be pressed and released on a roller surface of a rubber cylinder facing the impression cylinder. And a sequence control mechanism that rotates the pressure cylinder in contact with the rubber cylinder for a certain period of time while the cleaning body is pressed against the rubber cylinder, and cleaning the impression cylinder together with the cleaning of the rubber cylinder. A cleaning device characterized in that

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