JPH0449708B2

JPH0449708B2 -

Info

Publication number: JPH0449708B2
Application number: JP59185352A
Authority: JP
Inventors: Hiroyoshi Hosomura; Katsumi Harada; Tsukasa Matsuda
Original assignee: Fuji Xerox Co Ltd
Current assignee: Fujifilm Business Innovation Corp
Priority date: 1984-09-06
Filing date: 1984-09-06
Publication date: 1992-08-12
Also published as: JPS6163854A

Description

[Detailed description of the invention]

〔産業上の利用分野〕本発明は電子写真用転写紙、詳しく言えば主と
して電子写真方式の複写機やプリンターに使用さ
れる転写紙に関するものである。〔従来の技術〕近年、製紙業界では、インデイア紙、ライスペ
ーパー等の薄葉紙や金属合紙、防錆紙、電気絶縁
紙、写真印画紙等の特殊紙の分野で実施されてき
た中性抄紙技術を印刷および筆記用の上質紙の製
造に応用する動きが顕著になつている。この中性
抄紙はPH7.0以上の水媒体を用いて抄紙するもの
で、サイズ剤として中性サイズを使用し、填料を
配合する場合には主に炭酸カルシウムを使用する
ものである。上質紙の中性紙化は資源豊富で安価
な炭酸カルシウムを填料として使用して製造コス
トを低減することが大きなねらいであり、その他
用紙製造上の省エネルギー、省資源、生産性向
上、設備の汚損改善、廃水の浄化等の利得をもね
らいとするものである。例えば、特願昭58−
064598号、同58−036623号に示されているような
中性上質紙は電子写真用複写機に使用すると紙送
り性等の適正がないばかりでなく、感光体を摩耗
してコピー質を低下させたり、感光体自身の寿命
を縮める重大な欠点があることが判明した。この
感光体摩耗の現象はクリーニングブレード方式の
複写機で顕著に発生する。また、この現象から考
えると紙送り装置に使用されているゴムロールや
ゴムベルト、クリーニングブレード、定着ロール
等についても当然摩耗が懸念される。欧米では一
部の電子写真用転写紙が中性抄紙されているが、
そのような転写紙についても前記と同様の現象が
認められる。現在ほとんどの上質紙、電子写真用
転写紙は特開昭54−22831号や特開昭54−18740号
等に開示されているように酸性紙であるが、これ
らの用紙では感光体の摩耗は認められず、前記の
欠点は中性紙特有の問題と判断される。〔発明が解決しようとする問題点〕本発明は前記した欠点を解消し、感光体摩耗の
少ない中性電子写真転写紙を提供するものであ
る。〔問題点を解決するための手段及び作用〕本発明者等は感光体に付着した紙粉中に存在す
る填料の炭酸カルシウムがクリーニングブレード
等によつて感光体表面に圧接かつ摩擦されること
により感光体の摩耗が発生することをつきとめ
た。また、炭酸カルシウムが酸性の上質紙や電子
写真用転写紙に使用されている填料のタルクやク
レーより硬いために感光体を摩耗させ易いこと、
粒径の大きな炭酸カルシウムの紙への配合を少な
くすると感光体摩耗現象を改善できることを見出
し本発明を完成した。すなわち、本発明の電子写真転写用紙は、感光
体に付着したトナーを前記感光体と接するブレー
ドでクリーニングする電子写真方式の画像形成装
置に用いられる転写紙であつて、粒径15μ以下が
97重量％以上の粒度分布を有する炭酸カルシウム
から成る填料を、前記炭酸カルシウムが15重量％
を越えない範囲で配合したことを特徴とするもの
である。炭酸カルシウムとしては石灰石、白亜等を粉砕
した重質単関カルシウム、化学的に製造した沈降
性炭酸カルシウムが使用できる。従来の中性上質
紙では粒径15μ以上のものが５％から15％以上の
粒径分布を有するものが一般に使用されており、
これらの用紙では前記したように感光体摩耗を発
生する。所要の粒度分布は重質炭酸カルシウムの
場合には粉砕と分級によつて、また沈降性炭酸カ
ルシウムの場合には反応条件の調整と分級によつ
て得ることができる。これら炭酸カルシウムの配
合量は15％以下である。また炭酸カルシウムに摩耗性の小さいタルク、
カオリン等を総填料配合量が上記配合量を超えな
い範囲で配合することができる。内添サイズ剤と
してはアルキルケテンダイマー系、無水アルケニ
ルコハク酸系サイズ等を使用する。また、コピー適性、走行性、カール性等の電子
写真複写機適性を付与するために原料の配合、調
整、製造条件のコントロールが行われる（特公昭
44−3673号、特公昭46−24199号、特公昭55−
47385号、特開昭55−142799号参照）。すなわち、
適当なコピー画像濃度を維持し、バツクグランド
（白紙部分）の汚れを防ぐために、塩化ナトリウ
ム、塩化カリウム、スチレン−マイレン酸コポリ
マー、第四級アンモニウム塩等の導電剤を抄紙機
のサイズプレスで表面塗布して転写紙の表面電気
抵抗（JIS Ｃ−2111による）を10⁹〜10¹⁰Ω（湿度
（R.H.）65％、温度20℃）にする。またコピー画
像部の鮮鋭度を向上させるために表面の凹凸を少
なくして転写紙の平滑度（JIS Ｋ−6911に準じて
測定）を20秒以上にする。また転写紙の部分的吸
湿による膨潤やカールが発生すると転写時に複写
機の感光体と転写紙との密接度が低下し、コピー
画像濃度の低下やコピーの部分的な抜けが発生す
るのでこれを防止するために紙の水分を4.5〜5.5
％にして保管時に吸脱湿が発生しないように防湿
包装紙で包装する。〔実施例〕次に実施例及び比較例により本発明の電子写真
用転写紙を説明する。実施例１〜３及び比較例１〜３表１に示したような填料配合、パルプ配合、内
添サイズ剤、表面サイズ剤によつて７種の転写用
紙（実施例１〜５、比較例１〜２）を調整した。
また同時に市販の中性上質紙（比較例３）につい
ても、坪量、厚さ、クリーニングブレード方式の
複写機についての感光体摩耗度、黒すじや白抜け
等の発生によるコピー質への影響を評価した。炭酸カルシウムの粒径は原料の状態では沈降法
により測定した。また紙についても水で離解して
サンプルを得て走査型電子顕微鏡により炭酸カル
シウムの粒径を測定した。感光体摩耗に [Industrial Application Field] The present invention relates to an electrophotographic transfer paper, and more specifically, to a transfer paper used mainly in electrophotographic copying machines and printers. [Conventional technology] In recent years, in the paper industry, neutral papermaking technology has been implemented in the field of thin paper such as India paper and rice paper, and special paper such as metal interleaving paper, rust-proof paper, electrical insulation paper, and photographic paper. There is a growing trend to apply paper to the production of high-quality paper for printing and writing. This neutral paper is made using an aqueous medium with a pH of 7.0 or higher, uses a neutral size as a sizing agent, and mainly uses calcium carbonate when adding filler. The main aim of converting high-quality paper to acid-free paper is to reduce manufacturing costs by using resource-rich and inexpensive calcium carbonate as a filler, as well as to save energy and resources in paper manufacturing, improve productivity, and prevent equipment pollution. It also aims at benefits such as improvement and purification of wastewater. For example, the patent application 1983-
When used in electrophotographic copying machines, neutral high-quality papers such as those shown in No. 064598 and No. 58-036623 not only do not have proper paper feeding properties, but also wear out the photoreceptor and deteriorate copy quality. It has been found that there are serious drawbacks, such as shortening the life of the photoreceptor itself. This phenomenon of photoreceptor wear occurs significantly in cleaning blade type copying machines. Furthermore, considering this phenomenon, there is naturally a concern that the rubber rolls, rubber belts, cleaning blades, fixing rolls, etc. used in the paper feeding device may be worn out. In Europe and America, some electrophotographic transfer paper is made from neutral paper,
The same phenomenon as described above is also observed with such transfer paper. Currently, most of the high-quality paper and transfer paper for electrophotography are acidic papers, as disclosed in Japanese Patent Application Laid-Open Nos. 54-22831 and 18740-1980, but these papers do not cause abrasion of the photoreceptor. This is not recognized, and the above-mentioned drawbacks are considered to be problems specific to acid-free paper. [Problems to be Solved by the Invention] The present invention solves the above-mentioned drawbacks and provides a neutral electrophotographic transfer paper with less wear on the photoreceptor. [Means and effects for solving the problem] The present inventors discovered that calcium carbonate, which is a filler present in paper powder adhering to a photoreceptor, is pressed against and rubbed against the surface of the photoreceptor by a cleaning blade or the like. It was found that the photoreceptor wears out. In addition, calcium carbonate is harder than the fillers talc and clay used in acidic high-quality paper and electrophotographic transfer paper, so it easily wears out the photoreceptor.
The present invention was completed by discovering that photoreceptor abrasion can be improved by reducing the amount of calcium carbonate with large particle size added to paper. That is, the electrophotographic transfer paper of the present invention is a transfer paper used in an electrophotographic image forming apparatus in which toner adhering to a photoreceptor is cleaned with a blade in contact with the photoreceptor, and the paper has a particle size of 15 μm or less.
A filler consisting of calcium carbonate having a particle size distribution of 97% by weight or more is added, and the calcium carbonate is 15% by weight.
It is characterized in that it is blended within a range that does not exceed. As the calcium carbonate, heavy calcium carbonate obtained by crushing limestone, chalk, etc., and precipitated calcium carbonate produced chemically can be used. Conventional neutral high-quality paper is generally used with a particle size distribution of 5% to 15% or more with a particle size of 15μ or more.
With these papers, photoreceptor wear occurs as described above. The required particle size distribution can be obtained in the case of ground calcium carbonate by grinding and classification, and in the case of precipitated calcium carbonate by adjusting the reaction conditions and classification. The amount of calcium carbonate added is 15% or less. Calcium carbonate also has less abrasive talc,
Kaolin or the like may be blended within the range in which the total filler blending amount does not exceed the above blending amount. As the internal sizing agent, alkyl ketene dimer type, alkenyl succinic anhydride type size, etc. are used. In addition, the blending, adjustment, and manufacturing conditions of raw materials are controlled in order to impart properties suitable for electrophotographic copying machines, such as copyability, runnability, and curling properties.
No. 44-3673, Special Publication No. 1984-24199, Special Publication No. 1987-
47385, JP-A-55-142799). That is,
To maintain appropriate copy image density and prevent background (white paper) stains, conductive agents such as sodium chloride, potassium chloride, styrene-maleic acid copolymer, and quaternary ammonium salts are applied to the surface using the size press of the paper machine. The surface electrical resistance of the transfer paper (according to JIS C-2111) is set to 10 ⁹ to 10 ¹⁰ Ω (humidity (RH) 65%, temperature 20°C) by coating. In addition, in order to improve the sharpness of the copy image area, surface irregularities are reduced and the smoothness of the transfer paper (measured according to JIS K-6911) is set to 20 seconds or more. Also, if swelling or curling occurs due to partial absorption of moisture in the transfer paper, the closeness between the copying machine's photoreceptor and the transfer paper will decrease during transfer, resulting in a decrease in copy image density and partial omissions in the copy. To prevent paper moisture from 4.5 to 5.5
% and packaged with moisture-proof wrapping paper to prevent moisture absorption and desorption during storage. [Example] Next, the electrophotographic transfer paper of the present invention will be explained with reference to Examples and Comparative Examples. Examples 1 to 3 and Comparative Examples 1 to 3 Seven types of transfer paper (Examples 1 to 5, Comparative Example 1 ~2) was adjusted.
At the same time, regarding the commercially available neutral high-quality paper (Comparative Example 3), we investigated the basis weight, thickness, degree of wear of the photoconductor for cleaning blade type copiers, and the effects on copy quality due to the occurrence of black streaks and white spots. evaluated. The particle size of calcium carbonate was measured in the raw material state by a sedimentation method. Paper was also disintegrated with water to obtain a sample, and the particle size of calcium carbonate was measured using a scanning electron microscope. For photoreceptor wear

【表】ついてはクリーニングブレード方式の複写機を使
用してトナー現像を行わずに用紙を5000枚走行さ
せ、クリーニングブレード上で補集した紙粉の
XPS（Ｘ−ray Photoelectron Spectro−scopy）
分析で感光体成分の有無を判定した。コピー質は
感光体摩耗テストと同じ条件で用紙を１万枚走行
した後にトナー現像してコピーを取り、黒すじ、
白抜けの有無で判定した。〔発明の効果〕本発明によつて使用される炭酸カルシウムは粒
径15μ以下の細かいものの割合が高く、しかも用
紙への配合割合が15重量％以下と少ないので、感
光体の摩耗を顕著に減少させることができる。ま
た、本発明によれば、粒径の大きな炭酸カルシウ
ムを多量配合することがないので、用紙同志の滑
りは良好であり、従つてカセツトから用紙を搬送
するのに大きなトルクを必要としない利点があ
る。[Table] Using a cleaning blade type copying machine, 5,000 sheets of paper were run without toner development, and the paper dust collected on the cleaning blade was measured.
XPS (X-ray Photoelectron Spectro-scopy)
The presence or absence of photoreceptor components was determined by analysis. The copy quality was determined by running 10,000 sheets of paper under the same conditions as the photoreceptor wear test, developing the toner, and making copies.
Judgment was made based on the presence or absence of white spots. [Effects of the Invention] The calcium carbonate used in the present invention has a high proportion of fine particles with a particle size of 15μ or less, and the blending ratio in the paper is small at 15% by weight or less, so wear on the photoreceptor is significantly reduced. can be done. Further, according to the present invention, since a large amount of calcium carbonate with a large particle size is not blended, the slippage between the sheets is good, and therefore there is an advantage that large torque is not required to convey the sheets from the cassette. be.

Claims

[Claims]

1 A transfer paper used in an electrophotographic image forming apparatus that cleans toner adhering to a photoreceptor with a blade in contact with the photoreceptor, which has a particle size of
1. An electrophotographic transfer paper characterized in that a filler consisting of calcium carbonate having a particle size distribution of 97% by weight or less of 15μ or less is blended in an amount that does not exceed 15% by weight of calcium carbonate.