TWI677462B - Paper made from wood pulp, laminate, method for protecting metal plates, printing plates or glass plates, and method for feeding paper made from wood pulp - Google Patents

Abstract

An object of the present invention is to provide a paper which is a paper using wood pulp as a raw material and which can stably perform a paper feeding operation.

The invention is a paper using wood pulp as a raw material. The average deviation (MMD) of the friction coefficient of the surface measured by the KES method is 0.022 or less, and the texture index of the surface is 90 or more.

Description

Method for protecting paper, laminated body, metal plate, printing plate or glass plate using wood pulp as raw material, and method for supplying paper using wood pulp as raw material

The invention relates to a paper, which is a paper using wood pulp as a raw material, and can stably perform paper feeding operations.

Generally speaking, various paper systems such as printing paper, engineering paper, and spacer paper, which use wood pulp as a raw material, are laminated in the form of a plurality of papers and circulated on the market. When used, the paper is taken out of the laminate one by one.

In various industrial applications, the operation of taking out paper from the laminated body is usually mechanized or automated for the sake of efficiency. For example, holding means such as gripping means such as jigs and suction means such as vacuum pads are used to maintain the top-level paper of the laminated body. At the end, the paper is fed to the next step one by one by moving the holding means (Patent Document 1, Patent Document 2).

[Prior technical literature]

[Patent Literature]

[Patent Document 1]: Japanese Patent Laid-Open No. 2008-230853

[Patent Document 2]: Japanese Patent Laid-Open No. 2013-124169

However, in the case where the uppermost paper of the paper laminate is held by the holding means and the holding means is moved, there are cases in which the next piece of paper is brought into contact with the uppermost paper and moved, so that The position of the next sheet changes from the initial position.

In this way, if the position of the paper to be fed is changed, the holding means cannot maintain the fixed position of the paper, and it is difficult to stably feed the paper. In particular, if the variation in the position of the paper becomes large, it becomes difficult to perform an automatic take-out operation using a machine at high speed.

Therefore, it is considered to reduce the contact area between the uppermost paper and the next paper when the uppermost paper of the laminated body moves, thereby suppressing the movement of the next paper.

However, it has been confirmed that even if the holding means is moved not only in a direction horizontal to the paper surface of the next paper but also in a direction away from the paper surface in order to reduce the contact area between the top paper and the next paper, it cannot be suppressed. A piece of paper moves.

An object of the present invention is to provide a paper, which is a paper using wood pulp as a raw material, and can stably perform paper feeding operations.

In particular, an object of the present invention is to provide a paper which is in a paper feeding state by holding an end portion of the uppermost paper of a laminate of paper using wood pulp as a raw material and moving the paper away from the paper surface, It is possible to suppress the position change of the next sheet in contact with the uppermost sheet.

The present inventors conducted intensive studies and found that the above-mentioned problems can be solved by setting the mean deviation (MMD) of the coefficient of friction (MMD) of the surface of the paper using wood pulp as a raw material and setting the texture index to a specific range, thereby completing the present invention. invention.

The first aspect of the present invention is a paper using wood pulp as a raw material. The average deviation (MMD) of the friction coefficient of the surface measured by the KES method is 0.022 or less, and the texture index of the surface is 90 or more.

The MMD is preferably 0.018 or less.

The texture index is preferably 100-210.

The basis weight of the paper of the present invention is preferably 20 to 80 g / m ² .

The paper of the present invention is preferably a spacer paper.

The spacer is preferably a spacer for a metal plate.

The above-mentioned spacer paper is preferably a spacer paper for printing plates.

The spacer paper is preferably a spacer paper for a glass plate.

The glass plate is preferably used for a display.

The display is preferably a TFT liquid crystal display or an organic EL display.

A second aspect of the present invention is a laminated body composed of at least one paper of the first aspect of the present invention and at least one metal plate, printing plate, or glass plate.

In the laminated body, a plurality of the metal plate, the printing plate, or the glass plate are preferably present, and the paper is present between the plurality of metal plates, the printing plate, or the glass plate.

The third aspect of the present invention is a protection method for a metal plate, a printing plate, or a glass plate. The method includes the steps of inserting the paper of the first aspect of the present invention between a plurality of metal plates, printing plates, or glass plates.

A fourth aspect of the present invention is a feeding method, which is a paper feeding method using wood pulp as a raw material, and includes a step of holding an end portion of the laminated paper by a holding means, and the holding means. A step of moving away from the surface of the paper or its extended surface;

The average deviation (MMD) of the friction coefficient measured by the KES method is set to 0.022 or less, and the texture index is set to 90 or more.

According to the present invention, it is possible to provide a paper which uses wood pulp as a raw material and can stably perform a paper feeding operation.

In particular, by holding the end portion of the uppermost paper of the laminated body of the paper of the present invention by the holding means and moving the paper away from the paper surface, the paper feed state can be suppressed from contacting with the uppermost paper. The position of the next sheet changes. Therefore, according to the present invention, the holding means can maintain the fixed position of the paper, so that the paper can be stably fed. In particular, according to the present invention, it is possible to stably perform an automatic take-out operation of paper from a laminated body of paper at a high speed by a machine.

The invention relates to a paper using wood pulp as a raw material. The average deviation (MMD) of the friction coefficient of the surface measured by the KES method is 0.022 or less, and the texture index of the surface is 90 or more.

The wood pulp that can be used in the present invention is the use of conifer bleached kraft pulp (NBKP), broadleaf bleached kraft pulp (LBKP), conifer bleached sulfite pulp (NBSP), broadleaf bleached sulfite pulp (LBSP), thermo-mechanical Wood pulp (TMP) and other wood pulp or a mixture of them. Coniferous bleached kraft pulp (NBKP) and coniferous bleached sulfite pulp (NBSP) are preferred. This wood pulp can be used as the main body, and modified wood such as hemp, bamboo, yam, kenaf, fragrant tree, knotwood, or kapok can be used alone or in combination with modified wood, such as cationized wood pulp and mercerized wood pulp. Pulp, rayon, vinylon, nylon, acrylic resin, polyester and other synthetic or chemical fibers, or microfibrillated wood pulp. However, if a large amount of the resin component is contained in the wood pulp, it may cause adverse effects such as contamination of the surface of the object in contact with the paper of the present invention. Therefore, it is preferable to use a chemical wood pulp having as little resin component as possible, For example conifer bleached kraft pulp. In addition, high-yield wood pulp such as crushed wood pulp is not good because it contains a large amount of resin components. Furthermore, if synthetic fibers or chemical fibers are mixed, the machinability is improved, and the workability when the paper is made into a lithographic plate is improved. However, the recyclability in terms of waste disposal is poor, so it is necessary to pay attention.

In addition, as long as the performance of the present invention is not impaired, if necessary, an adhesive, a mildew-proofing agent, various paper-making fillers, a wet paper strength enhancer, and a dry paper strength can be added to the paper-making fibers mainly composed of the above-mentioned wood pulp. Enhancers, sizing agents, colorants, fixatives, antistatic agents, yield improvers, viscosity control agents, etc. In addition, it is necessary to pay close attention to avoid mixing with insects or dirt when adding these drugs.

When producing the wood pulp for paper of the present invention, the effect of enhancing the strength between paper layers can be expected if wood pulp is beaten. However, if the fine fibers in the wood pulp increase due to beating, there is a possibility that paper dust may be generated during use. Therefore, it is not preferable to perform beating more than necessary. Therefore, in the present invention, the preferred beating degree is 300 to 650 mlc.s.f.

It is possible to obtain the above-mentioned wood pulp by conventional methods, such as a well-known and existing long-net type papermaking machine, a cylinder type papermaking machine, a short-net type papermaking machine, a combination of a long-net type and a cylinder type papermaking machine, Paper of the invention.

The paper of the present invention may be composed of multiple layers, but is preferably a single layer.

The thickness of the paper of the present invention is preferably 0.01 to 2 mm, more preferably 0.05 to 1 mm, and even more preferably 0.1 to 0.5 mm.

The basis weight of the paper of the present invention is preferably 20 to 80 g / m ² , more preferably 25 to 70 g / m ² , and even more preferably 30 to 60 g / m ² .

The density of the paper of the present invention is preferably 0.40 to 1.10 g / cm ³ , more preferably 0.5 to 1.00 g / cm ³ , and still more preferably 0.60 to 0.90 g / cm ³ .

In the first aspect of the present invention, the average deviation (MMD) of the surface friction coefficient measured by the KES method of the paper of the present invention is 0.022 or less, and the texture index of the surface is 90 or more.

MMD uses a friction tester (KES-SE manufactured by Kato Tech Co., Ltd.). The side of a 10 mm square friction element composed of a bundle of piano wires with a diameter of 0.5 mm is 50 g / cm ^{2 on} one side. Contact pressure The average deviation of the friction coefficient measured by contacting the surface of the paper fixed with a tension of 20 g / cm while moving 2 cm at a specimen moving speed of 0.1 cm / sec in the same direction as the direction in which the tension was applied.

If the MMD is large, it means that the friction coefficient of the paper surface varies greatly according to the position of the paper surface, and microscopically, it means that the minute irregularities on the surfaces of the paper are increased. If the MMD exceeds 0.022, the minute irregularities on the surfaces of the papers increase, so that the blocking of the papers with each other increases, which is not good.

The MMD is preferably 0.020 or less, more preferably 0.019 or less, even more preferably 0.018 or less, and still more preferably 0.017 or less.

The MMD is, for example, preferably from 0.001 to 0.022, more preferably from 0.002 to 0.020, and even more preferably from 0.004 to 0.019.

"Formation Index" is a standard for the uniformity of the fiber structure of paper. The method for determining the texture index is described in US Patent No. 6,440,267. US Patent No. 6,440,267 is incorporated by reference as part of this specification. Specifically, the texture index can be measured using a paper sheet uniformity tester (for example, a uniformity tester FMT-MIII, manufactured by Nomura Corporation).

If the texture index is small, it means that the fibers in the paper are evenly distributed, and there are too few or too few fibers, so macroscopically it means that the surface shape of the paper is more uniform. However, the more uniform the surface shape of the paper surface means that the paper surface is closer to a flat surface, and the contact area between the papers will increase. If the texture index is less than 90, the contact area of the paper surface will increase, and the offset caused by the friction between the papers will increase, which is not good.

The texture index is preferably 95 or more, more preferably 98 or more, and even more preferably 100 or more.

The texture index is, for example, preferably 95 to 300, more preferably 98 to 250, and even more preferably 100 to 210. The method of setting the texture index to a specific range can be a known method, for example, Examples include the conditions for adjusting the papermaking speed, adjusting the wood pulp slurry concentration, adjusting the pulp net speed ratio (J / W ratio) of the mesh part in the papermaking step, adjusting the wire vibration device, adjusting the tension or suction conditions of the wire, or Adjust the conditions of the small printing roller. The J / W ratio is the ratio of the speed of the slice jet to the speed of the wire in relation to the wood pulp slurry sprayed from the headbox.

In the first aspect of the present invention, the average deviation (MMD) of the friction coefficient of the surface measured by the KES method is set to 0.022 or less to reduce the minute unevenness on the paper. On the other hand, the surface texture index is set For 90 or more, the large surface shape of the paper surface is intentionally non-uniform, thereby reducing the area where the papers contact each other, thereby reducing the offset caused by friction, and reducing the blocking caused by the small unevenness on the contact surface.

The method for producing the paper of the first aspect of the present invention is not particularly limited. The paper of the first aspect of the present invention can be produced by appropriately selecting the type of wood pulp that is the raw material of the paper, but in order to make it universal Wood pulp is used as a raw material to manufacture the paper of the first aspect of the present invention, and it is preferable to perform calendering, super calendering, soft nip calendering, embossing, etc. during the manufacturing process of the paper of the present invention and / or after manufacturing machining. By such processing, the surface properties of the paper of the present invention can be adjusted, and thus the MMD and texture index of the paper surface can be adjusted.

The application of the paper of the first aspect of the present invention is not limited, and may be various printing papers or non-printing papers. Examples of the non-printing paper include engineering paper and spacer paper. Regardless of the application, the paper of the first aspect of the present invention is preferably a paper of a type that holds the end portion and feeds the paper. Most of this type of paper are relatively large and relatively heavy paper, and most are discontinuous paper in a properly cut state rather than continuous paper in the form of a roll.

The paper of the first aspect of the present invention is preferably a spacer paper. The spacer paper is used to protect the surface of a metal plate, a printing plate (where a photosensitive image-forming layer is present on a substrate), and a glass plate, for example. Therefore, the paper of the first aspect of the present invention is preferably a spacer for metal plates, a spacer for printing plates, or a spacer for glass plates.

As such, the second aspect of the present invention is a laminated body composed of at least one paper of the first aspect of the present invention and at least one metal plate, printing plate, or glass plate.

In the laminated body of the present invention, there are preferably a plurality of the metal plate, the printing plate, or the glass plate, and the paper of the first aspect of the present invention exists in a plurality of the metal plate, the printing plate, or the glass plate. between.

Moreover, the third aspect of the present invention is a method for protecting a metal plate, a printing plate, or a glass plate, and includes a step of inserting the paper of the first aspect of the invention between a plurality of metal plates, printing plates, or glass plates. .

In the case where the paper of the first aspect of the present invention is a spacer sheet for glass plates, the spacer sheet for glass plates of the present invention is used by being inserted between glass plates. For example, typically, the spacer paper for a glass plate of the present invention is inserted one by one between a plurality of glass plates to form a laminated body as a whole, and the laminated body becomes the object of storage and transportation. In this way, a spacer for a glass plate can be inserted between a plurality of glass plates to protect the glass plate. Moreover, you may package a glass plate single body or the said laminated body using the spacer for glass plates.

The glass plate is not particularly limited, but glass plates for flat panel displays such as plasma display panels, liquid crystal display panels (especially TFT liquid crystal display panels), and organic EL display panels are preferred.

In particular, with the increase in the size of displays, the size and weight of glass plates for flat-panel displays continue to increase, but the spacers for glass plates made of the paper of the first aspect of the present invention can protect such large or large The weight of the glass surface.

A fourth aspect of the present invention is a feeding method, which is a paper feeding method using wood pulp as a raw material, and is characterized by including a step of holding an end portion of the laminated paper by a holding means; and the holding means The step of moving in a direction away from the surface of the paper or its extended surface

The average deviation (MMD) of the friction coefficient measured by the KES method is set to 0.022 or less, and the texture index is set to 90 or more.

The MMD is preferably 0.020 or less, more preferably 0.018 or less, and even more preferably 0.017 or less.

The MMD is, for example, preferably 0.001 to 0.020, more preferably 0.002 to 0.018, and even more preferably 0.004 to 0.017.

The texture index is preferably 95 or more, more preferably 98 or more, and even more preferably 100 or more.

The texture index is, for example, preferably 95 to 300, more preferably 98 to 250, and even more preferably 100 to 210.

In the fourth aspect of the present invention, the type of the holding means for holding the end portion of the laminated paper is not limited. For example, any holding means used in the field of paper feeding, such as gripping means such as grips, a pair of rollers, and suction means such as a vacuum pad, can be used.

The paper held at the end by the above-mentioned holding means is preferably the uppermost paper of the laminated paper.

The above-mentioned end portion is also not particularly limited. An arbitrary portion of the peripheral portion of the paper can be used as the end portion. Specifically, a range of 1 to 50 cm from the periphery of the paper is preferred, and a range of 3 to 50 cm is preferred. A range of 40 cm is preferably a range of 5 to 30 cm.

The moving direction of the holding means is not particularly limited as long as it is a direction away from the surface of the paper or its extended surface. For example, if the holding means includes a movement vector in a direction away from the surface of the paper or its extended surface, the moving direction of the holding means may also include a movement vector in the direction of the surface of the paper or its extended surface. Specifically, the holding means may be moved from the paper surface in a vertical direction, and the holding means may be moved from the paper surface in an obliquely upward direction.

In the fourth aspect of the present invention, even if the stacked paper is moved by the holding means, it is possible to suppress a change in the position of a sheet of paper under contact with the paper. Therefore, in the fourth aspect of the present invention, the holding means can maintain the fixed position of the paper, so that the paper can be stably fed.

[Example]

Hereinafter, the present invention will be described more specifically using examples and comparative examples, but the scope of the present invention is not limited to the examples.

[MMD]

A friction tester (KES-SE manufactured by Kado Technology Co., Ltd.) will be used to make the side of a 10 mm square friction element composed of a piano wire bundle of 0.5 mm in diameter contact pressure at 50 g / cm ² to 20 g The average deviation of the friction coefficient measured on the surface of the paper whose tension is fixed at / cm is 2 mm at a sample movement speed of 0.1 cm / sec in the same direction as the direction in which the tension is applied.

[Texture Index]

The texture index was measured using a uniformity tester FMT-MIII (made by Nomura Corporation).

[Paper feed test]

The paper was cut to a size of half a chrysanthemum (636mmX470mm), and 7000 sheets were laminated. A commercially-available printing press of the type that feeds paper to the end of the paper, and continuously feeds 7,000 sheets at a speed of 7000 sheets / hour under an environment of 25 ° C and a relative humidity of 30%, and makes the following judgments .

：: The paper is not shifted, and paper can be fed stably.

○: During the paper feeding process, it can be observed that during the paper feeding of the topmost paper, the next paper is driven to move the position, but the printer continues the paper feeding operation without stopping.

×: During the paper feeding process, there were cases where the position of the next sheet was driven and the printing machine stopped when the top sheet was fed.

[Example 1]

Blend conifer bleached kraft pulp and broadleaf bleached kraft pulp at a mass ratio of 90:10 to make a wood pulp, mash it and adjust the beating degree to 520 ml c.sf, add it to the whole wood A cationic starch (trade name: paper strength agent DD4280, manufactured by Starlight PMC Co., Ltd.) having a pulp mass of 0.1 parts by mass was used as a paper strength enhancer to prepare a wood pulp slurry having a concentration of 0.2% by mass. Under the condition that the J / W ratio is 0.97, the paper is made by a Fourdrinier paper machine, and further, the paper is smoothed by a soft nip under a non-heating condition at a linear pressure of 60 kgf / cm or less. To obtain a paper with a basis weight of 55 g / m ² . The obtained paper had an MMD of 0.022 and a texture index of 93.

[Example 2]

Except that papermaking was performed under the condition that the J / W ratio was 0.95, a paper having a basis weight of 55 g / m ² was obtained in the same manner as in Example 1. The obtained paper had an MMD of 0.021 and a texture index of 102.

[Example 3]

A paper having a basis weight of 55 g / m ² was obtained in the same manner as in Example 1 except that smoothing treatment was performed at a linear pressure of 80 kgf / cm under a non-heating condition by soft nip rolling. The obtained paper had an MMD of 0.018 and a texture index of 93.

[Comparative Example 1]

A paper having a basis weight of 55 g / m ² was obtained in the same manner as in Example 1 except that the J / W ratio was set to 1.00. The obtained paper had an MMD of 0.021 and a texture index of 88.

[Comparative Example 2]

A paper having a basis weight of 55 g / m ² was obtained in the same manner as in Example 1 except that no rolling treatment was performed. The obtained paper had an MMD of 0.025 and a texture index of 94.

The paper feed test was performed using the paper obtained in the examples and comparative examples. As a result, Example 1 was ○, and Examples 2 and 3 were ◎, and the comparative examples were all ×.

Claims (21)

A paper using wood pulp as a raw material, the average deviation (MMD) of the friction coefficient of the surface measured by the KES method is 0.022 or less, and the texture index of the surface is 90 or more. For example, the paper of the first patent application scope, wherein the MMD is 0.018 or less. For example, the paper of the first scope of patent application, wherein the above-mentioned texture index is 100 ~ 210. For example, the paper for the second scope of the patent application, wherein the above-mentioned texture index is 100 ~ 210. For example, the paper of any one of the scope of patent applications 1 to 4 has a basis weight of 20 to 80 g / m ² . If the paper in any one of claims 1 to 4 is applied for, it is a spacer paper. For example, the paper in the scope of patent application No. 5 is a spacer paper. For example, the paper in the scope of patent application No. 6 is a spacer paper for metal plates. For example, the paper in the scope of patent application No. 7 is a spacer paper for metal plates. For example, the paper under the scope of patent application No. 6 is a spacer for printing plates. For example, the paper in the scope of patent application No. 7 is a spacer for printing plates. For example, the paper in the scope of patent application No. 6 is a spacer for glass plates. For example, the paper in the scope of patent application No. 7 is a spacer for glass plates. For example, the paper in the scope of patent application No. 12 in which the above glass plate is used for display. For example, the paper in the scope of patent application No. 13 in which the above glass plate is used for display. For example, the paper in the scope of application for patent No. 14 wherein the above display is a TFT liquid crystal display or an organic EL display. For example, the paper in the scope of patent application No. 15 in which the above display is a TFT liquid crystal display or an organic EL display. A laminated body composed of at least one paper according to any one of claims 1 to 17, and at least one metal plate, printing plate, or glass plate. For example, in the laminated body of the scope of application for item 18, a plurality of the metal plate, the printing plate, or the glass plate exist, and the paper exists between the plurality of metal plates, the printing plate, or the glass plate. A method for protecting a metal plate, a printing plate, or a glass plate includes the steps of: inserting the paper of any one of claims 1 to 17 between a plurality of metal plates, printing plates, or glass plates. A supply method is a paper supply method using wood pulp as a raw material, characterized in that it includes a step of holding an end portion of the laminated paper by holding means, and moving the holding means away from the surface of the paper or the Step of moving the extended surface; set the average deviation (MMD) of the friction coefficient of the surface of the paper measured by the KES method to 0.022 or less, and set the texture index to 90 or more.