Manufacturing method of toilet tissue paper

Abstract

To provide a manufacturing method of toilet tissue paper capable of improving yield even when using corrugated boards as a waste paper raw material.SOLUTION: A manufacturing method of toilet tissue paper includes, at least, a dissolution step 1 of dissolution of a waste paper raw material comprising only corrugated boards including a pulp to obtain a slurry, a refining step 2 of extraction of staple fibers and filaments from the slurry, a beating step 3 of beating the extracted filaments to prepare processed fibers, and a blending step 4 of blending a processed fiber waste paper pulp including the processed fibers and a staple fiber waste paper pulp including the staple fibers.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for producing toilet paper using recycled paper pulp made from recycled cardboard. [Background technology]

[0002] Conventionally, recycled paper pulp made from recycled paper such as newspapers and magazines has been used as a raw material for tissue paper such as toilet paper and paper towels. In particular, sanitary paper such as toilet paper is preferred to have a high degree of whiteness, and many are made from high-quality recycled paper or bleached with bleach. However, it is anticipated that there may be situations in which high-quality recycled paper cannot be obtained, and as a countermeasure to such situations, there is toilet paper made solely from recycled cardboard (see Patent Document 1 below).

[0003] Generally, corrugated cardboard is composed of a corrugated core sandwiched between two flat liners. The outer liner, the inner liner, and the core are made of different materials depending on their respective uses. For example, the outer liner is made from high-quality recycled paper because it needs to be impact-resistant to withstand external impacts and have a design that is aesthetically pleasing. High-quality recycled paper contains a large amount of kraft pulp, which has relatively long fibers, and the intertwining of the fibers results in a sturdy and beautiful outer liner. On the other hand, the inner liner is made from recycled paper with a low kraft pulp content because a relatively inexpensive one is sufficient. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Registered Utility Model No. 3235445 Summary of the Invention [Problem to be solved by the invention]

[0005] However, as mentioned above, although corrugated cardboard contains long-fiber pulp, in the process of producing recycled paper pulp and toilet paper from corrugated cardboard as a raw material, only short fibers are sieved out during screening, and long fibers are removed along with foreign matter, resulting in poor yield.

[0006] The present invention has been proposed in view of the above-mentioned circumstances, and provides a toilet paper manufacturing method that can produce toilet paper with a high yield even when cardboard is used as recycled paper raw material. [Means for solving the problem]

[0007] In order to achieve the above object, the toilet paper manufacturing method of the present invention is characterized by comprising a dissolving process in which waste paper raw material consisting only of cardboard containing pulp is dissolved to form a slurry, a screening process in which short fibers and long fibers are extracted from the slurry, a beating process in which the long fibers extracted in the screening process are beaten to produce processed fibers, and a mixing process in which processed fiber waste paper pulp containing the processed fibers is mixed with short fiber waste paper pulp containing the short fibers extracted in the screening process.

[0008] The toilet paper manufacturing method according to the present invention is characterized in that the screening process includes a foreign matter removal process for removing foreign matter from the slurry, and a sieving process for sieving the slurry into short fibers and long fibers. [Effects of the Invention]

[0009] The toilet paper manufacturing method of the present invention includes a dissolving process in which waste paper raw material consisting only of cardboard containing pulp is dissolved to form a slurry, a screening process in which short fibers and long fibers are extracted from the slurry, a beating process in which the long fibers extracted in the screening process are beaten to produce processed fibers, and a mixing process in which processed fiber waste paper pulp containing the processed fibers and short fiber waste paper pulp containing the short fibers extracted in the screening process are mixed. Processed fiber waste paper pulp is produced by extracting and beating the long fibers that were previously removed, and is used together with the short fiber waste paper pulp, resulting in a high yield.

[0010] In the toilet paper manufacturing method according to the present invention, the screening process includes a foreign matter removal process for removing foreign matter from the slurry, and a sieving process for separating the slurry into short fibers and long fibers. In the screening process, the slurry is passed through a multi-stage strainer to separate the foreign matter, long fibers, and short fibers. The sieved long fibers are also used as waste paper raw material, resulting in a high yield. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a process explanatory diagram showing the steps of a toilet paper manufacturing method according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0012] The toilet paper manufacturing method according to an embodiment of the present invention will be described below with reference to the drawings. Figure 1 shows an outline of the toilet paper manufacturing method according to this embodiment.

[0013] As shown in Figure 1, the toilet paper manufacturing method involves at least a dissolving process 1, a refining process 2, a beating process 3, a mixing process 4, a deinking process 5, a sterilization process 6, a papermaking process 7, a raw roll production process 8, and a product processing process 9, to produce tissue paper such as toilet paper.

[0014] In dissolution process 1, waste paper raw material is dissolved to form a slurry. The waste paper raw material consists only of corrugated cardboard. Corrugated cardboard contains kraft pulp, and the outer liner contains a large amount of long-fiber kraft pulp. Here, long fibers are, for example, fibers with a length of more than 1 mm, and fibers with a length of 1 mm or less are short fibers. In dissolution process 1, the waste paper raw material is placed in a pulper, and either water or hot water and chemicals such as surfactants are added and stirred. This breaks down the waste paper raw material into fibers to form a slurry.

[0015] In the screening process 2, short and long fibers are extracted from the slurry. Specifically, the process includes a foreign matter removal process 21, in which foreign matter is removed from the slurry, and a sieving process 22, in which the slurry is sieved into short and long fibers. In the foreign matter removal process 21, for example, heavy foreign matter such as paper clips and staples used to bind the waste paper raw material is removed using the centrifugal force of a liquid cyclone. Furthermore, foreign matter such as plastics that cannot be used as paper raw materials is removed using a screen separator. In the sieving process 22, for example, a screening device is used. The screening device has multiple strainers, each with a different hole size. For example, the first layer of the strainer removes fine dust from the slurry, allowing only long and short fibers to pass through. The second layer has countless holes large enough to allow only short fibers to pass through, and when the slurry passes through the second layer, only short fibers pass through the holes. Thus, long and short fibers are sieved out of the slurry.

[0016] In the beating process 3, the long fibers are beaten to produce processed fibers. The beating process 3 makes the lengths of the processed fibers and short fibers more uniform. At the same time, the fibers are fluffed, making them more likely to entangle with each other. Note that the short fibers do not go through the beating process 3.

[0017] In the mixing step 4, short fiber wastepaper pulp containing the short fibers extracted in the screening step 2 is mixed with processed fiber wastepaper pulp containing the processed fibers obtained through the beating step 3. In the mixing step 4, the short fiber wastepaper pulp and the processed fiber wastepaper pulp may be mixed using a mixer equipped with a screw or the like, or the short fiber wastepaper pulp and the processed fiber wastepaper pulp may be directly transported to the next step. Note that because the processed fiber wastepaper pulp has relatively high strength, it is possible to obtain a long length of toilet paper that is tightly wound under high tension as the final product, while the inclusion of short fiber wastepaper pulp also makes it possible to enhance smoothness.

[0018] In the de-inking process 5, ink printed on the waste paper material is peeled off and removed by flotation. In the sterilization process 6, the paper is sterilized with chemicals such as oxygen, hydrogen peroxide, ozone, and sodium hypochlorite.

[0019] Through the above steps, waste paper pulp containing a mixture of short fiber waste paper pulp and processed fiber waste paper pulp is produced.

[0020] In the papermaking process 7, the recycled paper pulp is processed by a paper machine to produce a long sheet of base paper, which is then wound on a Pope reel. The papermaking process 7 includes at least a wetting process 71 in which the suspension is filtered from the recycled paper pulp, a pressing process 72 in which water is squeezed out, and a drying process 73 in which the recycled paper is dried.

[0021] In the wetting process 71, waste paper pulp is spread on a mesh wire and the suspension is filtered through the mesh. In the pressing process 72, the pulp is passed between rollers with opposing peripheral surfaces to squeeze out the water. In the drying process 73, the pulp is dried in a drying device to obtain base paper. For example, a Yankee dryer or band dryer is used as the drying device.

[0022] In the raw paper roll preparation step 8, the raw paper is wound into a roll on a Pope reel to prepare a raw paper roll.

[0023] In the product processing process 9, a rewinder rewinds the raw roll to the specified product length. The raw roll is also perforated and cut to the specified product width. The product processing process 9 also includes a paper roll production process 91. In the paper roll production process 91, the base paper is layered and wound around a shaft to become what is known as rolled tissue paper. If necessary, the base paper may also go through a printing process to decorate it.

[0024] As described above, in the toilet paper manufacturing method, the sieving step 22 extracts long fibers that were previously removed, and the beating step 3 obtains processed fibers. The subsequent mixing step 4 mixes the short fiber recycled paper pulp and the processed fiber recycled paper pulp, resulting in a good yield and making it possible to obtain toilet paper that takes advantage of the advantages of both the short fiber recycled paper pulp and the processed fiber recycled paper pulp.

[0025] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various design modifications can be made to the present invention without departing from the scope of the claims. [Explanation of symbols]

[0026] 1 Melting process 2 Selection process 21 Foreign matter removal process 22 Sieving process 3 Beating process 4 Mixing process 5 Deinking process 6 Sterilization process 7 Paper making process 71 Wet process 72 Pressing process 73 Dryer process 8. Raw roll production process 9 Product processing process 91 Paper roll manufacturing process

Claims

1. A dissolving process in which the recycled paper material, consisting of only cardboard containing pulp, is dissolved to create a slurry. a screening step of extracting short fibers and long fibers from the slurry; a beating step of beating the long fibers extracted in the screening step to produce processed fibers; a mixing step of mixing the processed fiber waste paper pulp containing the processed fibers with the short fiber waste paper pulp containing the short fibers extracted in the screening step, A method for producing toilet paper.

2. The screening step a foreign matter removing step of removing foreign matter from the slurry; A sieving step of sieving the short fibers and the long fibers.

2. The toilet paper manufacturing method according to claim 1.

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