JP2004036017A

JP2004036017A - Newsprint

Info

Publication number: JP2004036017A
Application number: JP2002193064A
Authority: JP
Inventors: Seikichi Ninomiya; 二宮　生吉; Yasuyuki Wakabayashi; 若林　靖幸
Original assignee: Daio Paper Corp
Current assignee: Daio Paper Corp
Priority date: 2002-07-02
Filing date: 2002-07-02
Publication date: 2004-02-05

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a point jamming which is especially a trouble caused between the triangular plate of a rotary press and its nipping rollers and may break the nipping rollers or the like at some case. <P>SOLUTION: This newsprint is characterized by having a basis weight of 35 to 52 g/m<SP>2</SP>, an average coefficient of kinetic friction of 1.5 to 3.0N with a flat metal plate, measured according to a friction test measurement method defined in JIS P 8147, and a surface roughness of 0.1 to 2.0μm defined in JIS B 0601 and measured with a tracer type surface roughness measurer defined in JIS B 0651 for a flat metal plate. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、新聞用紙に関し、特に、印刷工程でのトラブルが少ない新聞用紙に関する。
【０００２】
【従来の技術】
近年、新聞業界では、デジタル技術の導入等によって印刷工程が大幅に短縮されたことから省人化が進んできている。従って、印刷工程でトラブルが発生した場合に、少人数でトラブルを復旧しなくてはならず、作業員の負担が増大している。また、人員導入による迅速な対処ができないため、発送の遅れの危険性も生じている。このようなことから、新聞用紙については印刷工程においてトラブルが生じないことが渇望されている。
【０００３】
ところで、現在、新聞印刷において生ずるトラブルは、断紙、シワ、紙流れなど多岐にわたるが、なかでも深刻な問題となっているのが剣詰まりである。剣先詰りは、新聞輪転機の特に三角板からニッピングローラまでに生ずるトラブルであり、一般に、新聞用紙が三角板上でたるんだり三角板先端で裂けたりして、くしゃくしゃになったままニッピングロールに送られ、新聞用紙がニッピングローラをスムーズに通過できずに詰まったり、三角板上に飛び出してきたりするトラブル等をいう。剣先詰りは場合によってはニッピングローラ等を破損させることもある。
【０００４】
この剣先詰りの発生は、紙のコシと相関関係があることが知られている。具体的には、紙のコシが強いと重ねられた状態での折り適性が悪いことから、ニッピングロールの通過性が悪化し、剣先詰りが生じやすくなることが知られている。
【０００５】
【発明が解決しようとする課題】
これまで剣先詰りは、コシとの関係から、ニップロールの圧力を強化するとともに、紙厚を下げて紙のコシを柔らかくすることで対処されてきたが、このようにすると他の工程で断紙の発生や紙流れなど別のトラブルを招き易くなり、有効な解決策とはなっていない。
【０００６】
そこで、本発明の主たる課題は、印刷工程でのトラブル、特に、剣先詰りが生じない、新聞用紙を提供することにある。
【０００７】
【課題を解決するための手段】
上記課題を解決した請求項１記載の発明は、
坪量が３５〜５２ｇ／ｍ^２であり、かつ、
ＪＩＳ　Ｐ　８１４７に規定される摩擦試験測定方法に準拠して測定された金属板との平均動摩擦力が１．５〜３．０ｍＮであり、その金属板のＪＩＳ　Ｂ　０６５１に規定される触針式表面粗さ測定器で測定した表面粗さが０．１〜２．０μｍであることを特徴とする新聞用紙。
【０００８】
坪量を３５〜５２ｇ／ｍ^２としたことによりフォーマー部の折り特性が保持される。金属板との平均動摩擦力を１．５〜３．０ｍＮとしたことにより、三角板上での走行性に優れるものとなる。そして、これらの作用により、剣先詰りの発生率が格段に低下する。
【０００９】
請求項２記載の発明は、ＪＩＳ　Ｐ　８１１３に基づいて測定された、紙の縦方向の引張り強度が、２．０〜４．０ｋＮ／ｍである請求項１記載の新聞用紙である。
【００１０】
新聞用紙の印刷工程において特に破断のしやすさに影響する紙の縦方向の引張り強度を、２．０〜４．０ｋＮ／ｍとしたことにより、フォーマー部に限らず、新聞印刷にかかるその他の工程における新聞用紙の破断が生じずらくなる。
【００１１】
請求項３記載の発明は、ＪＰＡＮ　ＴＡＰＰ　Ｎｏ．６に規定される紙のｐＨ試験方法に基づいて測定されたｐＨ値が、ｐＨ３．５〜８．０である請求項１または２記載の新聞用紙である。
【００１２】
紙面のｐＨ値を酸性あるいは中性領域にしたので、無機填料の効果を高めることができる。
【００１３】
請求項４記載の発明の発明は、無機填料が乾燥パルプあたり０．２〜５重量％内添され、かつ、灰分率が３〜１０重量％である請求項１〜３の何れか１項に記載の新聞用紙である。より望ましいのは、灰分率が３〜７重量％である。
【００１４】
灰分率を３〜１０重量％としたので、紙粉が発生しにくい。また、平均動摩擦力の調整も容易となる。さらに、無機填料の効果が発揮されて裏抜けなどの印面低下がなくなる。
【００１５】
【発明の実施の形態】
本発明の実施の形態を以下に詳述する。本発明者らは、フォーマーにおいて新聞用紙が金属性の三角板に接して走行していることに着目し、三角板と紙との平均動摩擦力との相関について研究を行った。そうしたところ、三角板を構成する金属板とほぼ同様の表面粗さを有する金属板との平均動摩擦力が所定の数値である新聞用紙では、剣先詰りの発生がほとんどないことを知見した。
【００１６】
その本発明にかかる金属板との平均動摩擦力の範囲は、１．５〜３．０ｍＮである。この平均動摩擦力は、ＪＩＳ　Ｐ　８１４７に規定される水平方向の摩擦試験測定方法に準拠して測定した値である。具体的にＪＩＳ　Ｐ　８１４７と異なるところを述べれば、ＪＩＳ　Ｐ　８１４７に規定される水平方法での平均動摩擦力の測定方法は、水平台上に紙試料を固定しその上に所定の錘に固定した他の紙試料を重ね、当該錘とともにその他の紙試料を移動させて紙同士の平均動摩擦力を測定するものであるが、本発明においては水平台上に新聞用紙を固定し、その上に金属板を紙と面接触するように重ね、当該金属板を移動させて、新聞用紙と金属板との平均動摩擦力を測定するものとした。この場合において、紙試料の測定面は限定されない。一般にいう表裏面にかかわらず実際に三角板と接触する面を測定する。紙の縦横方向についても同様である。測定にもちいる新聞用紙はＪＩＳＳ　８１１０に基づいて調整する。その他、金属板の大きさや質量および測定時の移動速度はＪＩＳ　Ｐ　８１４７に規定される錘に関するものと同様とする。
【００１７】
ここで、金属板の表面粗さは平均動摩擦力に影響を与えることから、本発明においては、前記金属板は、ＪＩＳ　Ｂ　０６５１に規定される触針式表面粗さ測定器で測定した表面粗さが０．１〜２．０μｍのものとする。測定時のカットオフ値等は標準値とする。なお、本発明にかかる表面粗さは、ＪＩＳ　Ｂ　０６０１に定義される算術表面粗さにあたる。ここで、ＪＩＳ　Ｂ　０６０１に規定されるように物体の表面の特性は、厳密には触針式表面粗さ測定器で測定した表面粗さ（算術表面粗さ）のみで限定されるものではないが、本発明者らは、本発明に係る平均動摩擦力の測定においては、算術表面粗さを規定すれば十分であることを知見している。
【００１８】
一方、本発明の新聞用紙は、ＪＩＳ　Ｐ　８１１３に基づいて測定された、紙の縦方向の引張り強度が、２．０〜４．０ｋＮ／ｍであるのが望ましい。さらに好適な範囲は、２．５〜３．５ｋＮ／ｍである。縦方向の紙力が２．０ｋＮ／ｍ以下であると、当該範囲にない場合と比較して、三角板での折り重ね時に三角板先端で破断して剣先詰りが発生しやすくなる。反対に４．０ｋＮ／ｍより大きくても、三角板での折り重ねが不十分となり剣先詰りが発生しやすくなる。この紙力が大きい場合に剣先詰りが発生すると輪転機の剣先詰り発生近傍部位へ与える力が大きく、ニッピングローラ等を破損させて被害が大きくなりやすい。
【００１９】
また、本発明の新聞用紙は、ＪＰＡＮ　ＴＡＰＰ　Ｎｏ．６に規定される紙のｐＨ試験方法に基づいて測定されたｐＨ値が、ｐＨ３．５〜８．０であるのが望ましい。紙面ｐＨを酸性あるいは中性領域にすることで、無機填料の効果を最大限に発揮できる。アルカリ性領域では、無機填料が溶出し、紙中への歩留まり低下を招き、無機填料本来の裏抜け防止などの印面向上の効果が低くなる。紙面ｐＨを３．５〜８．０の領域に管理することで、剣先詰りを解消する平均動摩擦力の管理及び無機填料本来の裏抜け防止などの印刷適性向上を好適に発揮できる。
【００２０】
灰分が１０重量％を超えると、紙粉が発生しやすくなる。灰分が３重量％未満であると、平均動摩擦力の調整が難しくなり、また、無機填料の効果が低く裏抜けなどの印面低下が生じる。
【００２１】
本発明の新聞用紙は、長網抄紙機、ツインワイヤー型抄紙機等の従来既知の抄紙機によって原料パルプを抄紙する常法によって製造することができる。
【００２２】
前記原料パルプとしては、機械パルプ、化学パルプ、古紙パルプあるいは脱墨パルプ等が挙げられ、これらのパルプを単独あるいは任意の比率で混合して原料とすることができる。特に脱墨パルプに関しては、安価でありまた環境保護の観点からも使用が望ましいことから、近年、高配合化が進んでおり、従って、この脱墨パルプを３０〜７０％程度配合したものを原料とするのが望ましい。
【００２３】
また、本発明の新聞用紙は、乾燥パルプあたり０．２〜５重量％の無機填料を内添させて、灰分率を３〜１０重量％とするのが望ましい。灰分が１０重量％を超えると、紙粉の発生しやすくなる。灰分が３重量％未満であると、平均動摩擦力の調整が難しくなる。また、無機填料本来の効果が低く、裏抜けなどの印面低下が生じやすくなる。従って、剣先詰りの解消と無機填料本来の印刷適性向上を図るには、灰分率を３〜１０重量％とするのが望ましい。
【００２４】
前記無機填料としては、炭酸カルシウム、タルク、クレー、カオリン、ホワイトカーボン、酸化チタン等を使用することができるが、なかでも、ホワイトカーボン、タルクを使用することが好ましい。
【００２５】
また、本発明の新聞用紙は、平均動摩擦力に影響を与えない範囲で、表面処理剤、サイズ剤、紙力増強剤、耐水化剤、紫外線防止剤、退色防止剤などの従来既知の助剤などを使用することができる。
【００２６】
＜実施例＞
灰分率、紙面ｐＨ、平均動摩擦力、引張り強度の異なる新聞用紙を各種抄紙し、本発明にかかるものを実施例としそうでないものを比較例とした。新聞用紙は、古紙パルプ７０重量部およびサーモメカニカルパルプ３０重量部からなる混合パルプに無機填料を添加したパルプ原料を、ツインワイヤー型抄紙機にて抄紙して得た。新聞用紙の灰分率、紙面ｐＨ、平均動摩擦力、引張り強度は、無機填料の添加量、ｐＨ調整剤の添加量、抄紙機の運転条件等を調整して異ならしめた。坪量は全て４４ｇ／ｍ^２とした。
【００２７】
実施例および比較例について、新聞オフセット輪転機［三菱重工社製］にて１２〜１３万部／時で新聞印刷を行い、剣先詰り、断紙、紙粉発生等のトラブルが生ずるか否を確認した。剣先詰り等のトラブルが発生したか否の結果を、各実施例および各比較例の灰分率、紙面ｐＨ、平均動摩擦力、引張り強度の具体的な値とともに、表１に示す。
【００２８】
【表１】

【００２９】
表１に示されるとおり、本発明に係る実施例１〜５については、剣先詰り等のトラブルが発生しなかったのに対し、比較例１〜６は、剣先詰りや紙粉発生、断紙が発生する結果となった。
【００３０】
【発明の効果】
以上詳述のとおり、本発明によれば、印刷工程でのトラブル、特に、剣先詰りが生じない、新聞用紙が提供される。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to newsprint, and more particularly to newsprint with less trouble in a printing process.
[0002]
[Prior art]
2. Description of the Related Art In recent years, in the newspaper industry, the printing process has been significantly shortened due to the introduction of digital technology and the like, and labor saving has been progressing. Therefore, when a trouble occurs in the printing process, the trouble has to be recovered by a small number of people, and the burden on the worker is increasing. In addition, there is a danger of delays in shipping because prompt measures cannot be taken by introducing personnel. For this reason, it is desired that newsprint does not cause any trouble in the printing process.
[0003]
By the way, at present, troubles that occur in newspaper printing are various, such as paper cutting, wrinkling, and paper running. Among them, sword jamming is a serious problem. Sword tip clogging is a problem that occurs in newspaper rotary presses, especially from the triangular plate to the nip roller. It refers to troubles such as paper jamming without being able to pass through the nip roller smoothly, or jumping out onto a triangular plate. In some cases, the tip of the sword may damage the nipping roller and the like.
[0004]
It is known that the occurrence of the sword clogging has a correlation with the paper stiffness. Specifically, it is known that if the paper has a high stiffness, the suitability for folding in a stacked state is poor, so that the passability of the nip roll is deteriorated and the tip of the sword tends to be clogged.
[0005]
[Problems to be solved by the invention]
Until now, sword tip jamming has been dealt with by increasing the pressure of the nip roll and reducing the paper thickness to soften the paper stiffness due to the relationship with the stiffness. Other troubles such as generation and paper flow are likely to occur, and are not an effective solution.
[0006]
Accordingly, a main object of the present invention is to provide newsprint that does not cause troubles in the printing process, particularly, clogging of the sword.
[0007]
[Means for Solving the Problems]
The invention according to claim 1 which has solved the above-mentioned problem,
The basis weight is 35 to 52 g / m ² , and
The average kinetic friction force with a metal plate measured in accordance with the friction test measurement method specified in JIS P 8147 is 1.5 to 3.0 mN, and the stylus type of the metal plate specified in JIS B 0651 Newsprint paper characterized in that the surface roughness measured by a surface roughness measuring device is 0.1 to 2.0 μm.
[0008]
By setting the basis weight to 35 to 52 g / m ² , the folding characteristics of the former portion are maintained. By setting the average kinetic frictional force with the metal plate to 1.5 to 3.0 mN, the running property on the triangular plate becomes excellent. Then, due to these effects, the incidence of sword clogging is significantly reduced.
[0009]
The invention according to claim 2 is the newsprint according to claim 1, wherein the tensile strength of the paper measured in accordance with JIS P 8113 in the longitudinal direction is 2.0 to 4.0 kN / m.
[0010]
In the newsprint printing process, by setting the tensile strength in the longitudinal direction of the paper, which particularly affects the easiness of breakage, to be 2.0 to 4.0 kN / m, not only the former portion but also other newsprint related newsprints can be used. Breakage of newsprint in the process is less likely to occur.
[0011]
The invention according to claim 3 is a method according to JPAN TAPP No. The newsprint according to claim 1 or 2, wherein the pH value of the paper measured according to the paper pH test method specified in No. 6 is 3.5 to 8.0.
[0012]
Since the pH value of the paper is in the acidic or neutral range, the effect of the inorganic filler can be enhanced.
[0013]
The invention according to claim 4 is the invention according to any one of claims 1 to 3, wherein the inorganic filler is internally added in an amount of 0.2 to 5% by weight per dry pulp, and the ash content is 3 to 10% by weight. Newspaper as described. More preferably, the ash content is 3 to 7% by weight.
[0014]
Since the ash content is set to 3 to 10% by weight, paper powder is hardly generated. Further, the adjustment of the average dynamic friction force is also facilitated. In addition, the effect of the inorganic filler is exerted, so that the seal surface does not deteriorate such as strikethrough.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiments of the present invention will be described in detail below. The present inventors have paid attention to the fact that newsprint is running in contact with a metallic triangular plate in a former, and studied the correlation between the triangular plate and the average dynamic friction force between the paper and the triangular plate. In such a case, it has been found that sword tip clogging hardly occurs in newsprint in which the average kinetic friction force with a metal plate having substantially the same surface roughness as the metal plate constituting the triangular plate is a predetermined value.
[0016]
The range of the average dynamic friction force with the metal plate according to the present invention is 1.5 to 3.0 mN. The average dynamic friction force is a value measured in accordance with a horizontal friction test measurement method specified in JIS P8147. Specifically, the difference from JIS P 8147 is as follows. In the method of measuring the average dynamic friction force in the horizontal method defined in JIS P 8147, a paper sample is fixed on a horizontal table and a predetermined weight is fixed thereon. Another paper sample is stacked, and the other paper sample is moved together with the weight to measure the average kinetic friction force between the papers.In the present invention, newsprint is fixed on a horizontal table and metal The plates were stacked so as to make surface contact with the paper, the metal plates were moved, and the average kinetic friction force between the newsprint and the metal plates was measured. In this case, the measurement surface of the paper sample is not limited. The surface that actually contacts the triangular plate is measured regardless of the front and back sides. The same applies to the vertical and horizontal directions of the paper. Newspaper used for measurement is adjusted based on JISS 8110. In addition, the size and mass of the metal plate and the moving speed at the time of measurement are the same as those relating to the weight specified in JIS P8147.
[0017]
Here, since the surface roughness of the metal plate affects the average kinetic friction force, in the present invention, the metal plate has a surface roughness measured by a stylus type surface roughness measuring device specified in JIS B 0651. Is 0.1 to 2.0 μm. The cut-off value at the time of measurement is a standard value. The surface roughness according to the present invention corresponds to the arithmetic surface roughness defined in JIS B0601. Here, as stipulated in JIS B 0601, the surface characteristics of the object are not strictly limited only by the surface roughness (arithmetic surface roughness) measured by a stylus type surface roughness measuring device. However, the present inventors have found that it is sufficient to define the arithmetic surface roughness in the measurement of the average dynamic friction force according to the present invention.
[0018]
On the other hand, the newsprint of the present invention desirably has a tensile strength in the longitudinal direction of the paper of 2.0 to 4.0 kN / m, measured based on JIS P 8113. A more preferred range is from 2.5 to 3.5 kN / m. When the paper strength in the longitudinal direction is 2.0 kN / m or less, the tip of the triangular plate is broken at the time of folding on the triangular plate and the sword is more likely to be clogged than in the case where the paper force is not in the range. Conversely, if it is larger than 4.0 kN / m, folding with a triangular plate is insufficient and sword tip clogging is likely to occur. If the paper force is large and sword tip jam occurs, the force applied to the vicinity of the sword tip jam of the rotary press is large, and the nip roller and the like are damaged, and the damage tends to increase.
[0019]
In addition, the newsprint of the present invention is JPAN TAPP No. The pH value measured based on the paper pH test method specified in No. 6 is desirably pH 3.5 to 8.0. The effect of the inorganic filler can be maximized by setting the paper surface pH to an acidic or neutral range. In the alkaline region, the inorganic filler is eluted, causing a decrease in the yield into the paper, and the effect of improving the stamped surface such as the prevention of strike-through inherent in the inorganic filler is reduced. By controlling the paper surface pH in the range of 3.5 to 8.0, it is possible to suitably exert the improvement of printability such as the management of the average dynamic frictional force for eliminating the sword tip clogging and the prevention of strikethrough of the inorganic filler.
[0020]
If the ash content exceeds 10% by weight, paper powder is likely to be generated. When the ash content is less than 3% by weight, it is difficult to adjust the average dynamic frictional force, and the effect of the inorganic filler is low, resulting in deterioration of the stamped surface such as strikethrough.
[0021]
The newsprint of the present invention can be produced by a conventional method in which raw pulp is made by a conventionally known paper machine such as a fourdrinier paper machine or a twin-wire paper machine.
[0022]
Examples of the raw material pulp include mechanical pulp, chemical pulp, waste paper pulp, deinked pulp, and the like. These pulp can be used alone or as a mixture at an arbitrary ratio. In particular, since deinked pulp is inexpensive and is preferably used from the viewpoint of environmental protection, its blending has been advanced in recent years. Therefore, a blend of about 30 to 70% of this deinked pulp is used as a raw material. It is desirable that
[0023]
In addition, the newsprint of the present invention desirably contains 0.2 to 5% by weight of an inorganic filler per dry pulp to make the ash content 3 to 10% by weight. If the ash content exceeds 10% by weight, paper powder is likely to be generated. When the ash content is less than 3% by weight, it is difficult to adjust the average dynamic friction force. In addition, the inherent effect of the inorganic filler is low, and the stamp surface such as strikethrough tends to be reduced. Therefore, it is desirable to set the ash content to 3 to 10% by weight in order to eliminate the clogging of the sword and to improve the original printability of the inorganic filler.
[0024]
As the inorganic filler, calcium carbonate, talc, clay, kaolin, white carbon, titanium oxide and the like can be used, and among them, white carbon and talc are preferably used.
[0025]
In addition, the newsprint of the present invention is a conventional auxiliary agent such as a surface treatment agent, a sizing agent, a paper strength enhancer, a water-proofing agent, an ultraviolet ray inhibitor, and a fading inhibitor, as long as the average dynamic friction force is not affected. Etc. can be used.
[0026]
<Example>
Various newsprints having different ash content, paper surface pH, average kinetic frictional force, and tensile strength were made, and those according to the present invention were regarded as examples and those not according to the present invention as comparative examples. Newsprint paper was obtained by making a pulp raw material obtained by adding an inorganic filler to a mixed pulp composed of 70 parts by weight of waste paper pulp and 30 parts by weight of thermomechanical pulp using a twin-wire type paper machine. The ash content, paper surface pH, average kinetic friction force, and tensile strength of newsprint were varied by adjusting the amount of the inorganic filler, the amount of the pH adjuster, the operating conditions of the paper machine, and the like. The grammage was all 44 g / m ² .
[0027]
For the examples and the comparative examples, newspaper printing was performed at a newspaper offset rotary press [manufactured by Mitsubishi Heavy Industries] at 120,000 to 130,000 copies / hour, and it was confirmed whether or not troubles such as clogging of the sword, breakage of paper, and generation of paper dust would occur. did. Table 1 shows the results of whether or not a trouble such as sword tip clogging has occurred, together with specific values of the ash content, the paper surface pH, the average dynamic friction force, and the tensile strength of each of the examples and comparative examples.
[0028]
[Table 1]

[0029]
As shown in Table 1, in Examples 1 to 5 according to the present invention, troubles such as sword tip clogging did not occur, whereas in Comparative Examples 1 to 6, sword tip clogging, paper dust generation, and paper breakage occurred. The result was that it occurred.
[0030]
【The invention's effect】
As described in detail above, according to the present invention, newsprint is provided that does not cause troubles in the printing process, in particular, does not cause sword tip clogging.

Claims

The basis weight is 35 to 52 g / m ² , and
The average kinetic friction force with a metal plate measured in accordance with the friction test measurement method specified in JIS P 8147 is 1.5 to 3.0 mN, and the stylus type of the metal plate specified in JIS B 0651 Newspaper paper having a surface roughness of 0.1 to 2.0 μm measured by a surface roughness measuring device.

The newsprint according to claim 1, wherein the paper has a tensile strength in the longitudinal direction of 2.0 to 4.0 kN / m as measured according to JIS P # 8113.

JPAN {TAPP} No. The newsprint according to claim 1 or 2, wherein the pH value of the paper measured in accordance with the paper pH test method specified in (6) is from 3.5 to 8.0.

The newsprint according to any one of claims 1 to 3, wherein the inorganic filler is internally added in an amount of 0.2 to 5% by weight per dry pulp, and the ash content is 3 to 10% by weight.