Toilet roll and manufacturing method thereof

Abstract

To provide a toilet roll which has a long wound length, with space-saving planned for storage, which excels in feeling of toilet paper, and which prevents the toilet roll from rewinding.SOLUTION: A 2-ply toilet roll has a wound length of 33 m or more and 100 m or less, a wound diameter of 100 mm or more and 134 mm or less, wound density of 0.790 m / cm2 or more and 1.001 m / cm2 or less, and basis weight per sheet of 11 g / m2 or more and 16 g / m2 or less. The TS750 exterior surface is 12 dBV2 rms or more and 30 dBV2 rms or less. The TS750 interior surface is larger than TS750 exterior surface. The toilet paper is provided with a first joining embossment in which a joint area with two sheets adhered to each other is defined, and with a second joining embossment in which a joint area with two sheets joined is defined together with the first joining embossment, so that the two sheets are integrally joined with the first joining embossment, in the toilet roll.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a toilet roll in which two-ply toilet paper, each consisting of two overlapping sheets, is wound into a roll, and to a method for manufacturing the same. [Background technology]

[0002] In toilet rolls in which toilet paper is wound into a roll, the length of each roll is increased to save space when transporting and storing the roll. Patent Document 1 focuses on the smoothness of two-ply toilet paper, and proposes a long-wound toilet roll in which the TS750 values ​​measured by a tissue softness measuring device TSA are different on both sides of the toilet paper, the value of the outer surface is 12 to 27 dBV2rms, and the ratio of the values ​​of the inner surface and the outer surface is 1.06 to 2.30, improving the texture. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6262439 Summary of the Invention [Problem to be solved by the invention]

[0004] When toilet paper is smoothed as described above to improve the texture, when the manufactured toilet roll is used, due to the smoothness of the toilet paper, only one of the two sheets that make up the two plies of toilet paper (the sheet on the outer surface of the toilet paper, which is the surface on the outside of the roll) is easily pulled out from the roll and used, while the other sheet (the sheet on the inner surface of the toilet paper, which is the surface on the inside of the roll) remains unused on the roll. This tends to cause the order of stacking of the two sheets that make up the two plies of toilet paper in the toilet roll to be reversed, a condition known as "rewinding."

[0005] Fig. 8 is a diagram illustrating "rewinding" of a toilet roll. Fig. 8(a) shows a typical toilet roll 100 in a normal state. Fig. 8(b) shows the toilet roll 100 shown in Fig. 8(a) in a rewound state. As shown in Fig. 8(a) and (b), by rewinding, the sheet 110, which was previously on the outer side, becomes the inner side, and the sheet 120, which was previously on the inner side, becomes the outer side in the two-ply toilet paper 130, reversing the stacking order of the sheets.

[0006] When a toilet roll is rewound, problems can occur such as the ends of the two sheets that make up the toilet paper being misaligned because the sheets are not the same length, the toilet paper being difficult to pull out as two plies from the roll and easily falling apart, and if the toilet paper has perforations, the perforations of the two sheets becoming misaligned.

[0007] The present invention aims to provide a toilet roll that has a long winding length per roll, which saves space when transporting and storing the toilet roll, has an excellent texture, and is prevented from rewinding. [Means for solving the problem]

[0008] As a result of intensive research to solve the above problems, the present inventors have discovered a toilet roll in which two-ply toilet paper, each of which is made up of two overlapping sheets, is wound into a roll, and the roll length of the toilet roll is 33 m or more and 100 m or less. 、 Roll diameter is 100mm to 134mm , and winding density is 0.790m / cm 2 More than 1.001m / cm 2 below The basis weight per sheet is 11 g / m 2 More than 16g / m 2The TS750 outer surface, which is the intensity of the first maximum peak in the spectrum seen from the low frequency side when measured by the vibration sensor, is 12 dBV or less. The TS750 outer surface is measured by measuring the vibration of the sample stage using a tissue softness measuring device TSA. A bladed rotor is pressed from above with a pressure of 100 mN against a sample of toilet paper placed on the sample stage with the outer side of the roll facing up, and then the sample stage is rotated at a speed of 2.0 revolutions per second. 2 rms over 30dBV 2 It has been found that the above-mentioned problems can be solved by a toilet roll characterized in that the TS750 inner surface, which is the intensity of the first maximum peak in the spectrum seen from the low frequency side when a tissue softness measuring device TSA is used to measure the vibration of a toilet paper sample placed on a sample stage with the inner side of the toilet roll facing up, by pressing a bladed rotor from above with a pressing pressure of 100 mN and then rotating the sample stage at a rotation speed of 2.0 per second, the TS750 inner surface is greater than the TS750 outer surface, and the toilet paper has a first bonding embossed portion for defining a bonding area where two sheets come into close contact with each other, and a second bonding embossed portion which, together with the first bonding embossed portion, defines a bonding area where the two sheets come into close contact with each other and bonds the two sheets together with the first bonding embossed portion.

[0009] Specifically, the present invention has the following configuration.

[0010] [1] A toilet roll in which two sheets of toilet paper are overlapped and wound into a roll, The length of the toilet roll must be between 33m and 100m. 、 Roll diameter is 100mm to 134mm , and winding density is 0.790m / cm 2 More than 1.001m / cm 2 below and The basis weight per sheet is 11g / m 2 More than 16g / m 2 is as follows: Using the tissue softness measuring device TSA, a toilet paper sample is placed on the sample stage with the outer side of the roll facing up. A bladed rotor is pressed from above with a pressing pressure of 100mN, then rotated at a speed of 2.0 revolutions per second. The vibration of the sample stage is measured with a vibration sensor. The TS750 outer surface, which is the intensity of the first maximum peak in the spectrum seen from the low frequency side (TS750 value), is 12dBV. 2 rms over 30dBV 2 is less than or equal to rms, Using the tissue softness measuring device TSA, a toilet paper sample was placed on the sample stage with the inside of the roll facing up, and a bladed rotor was pressed from above with a pressing pressure of 100mN, then rotated at a speed of 2.0 revolutions per second. The vibration of the sample stage was measured with a vibration sensor, and the intensity of the first maximum peak in the spectrum from the low frequency side (TS750 value) was obtained. The TS750 inner surface was greater than the TS750 outer surface. Toilet paper is A first bonding embossment for defining a bonding area where two sheets are in close contact with each other; a second bonding embossed portion for defining a bonding area in cooperation with the first bonding embossed portion such that the two sheets are in close contact with each other, and for integrally bonding the two sheets together with the first bonding embossed portion; A toilet roll comprising:

[0011] [2] The toilet roll according to [1], characterized in that the sheet contains wood pulp, and the recycled paper pulp content in the sheet, calculated by the formula R÷(W+R)×100, is 0% by mass or more and less than 40% by mass, where W is the wood pulp content in the sheet and R is the recycled paper pulp content in the sheet. [3] A toilet roll in which two sheets of toilet paper are overlapped and wound into a roll, The length of the toilet roll must be between 33m and 100m. 、 Roll diameter is 100mm to 134mm , and winding density is 0.790m / cm2 More than 1.001m / cm 2 below , The basis weight per sheet is 11g / m 2 More than 16g / m 2 is as follows: Using the tissue softness measuring device TSA, a toilet paper sample is placed on the sample stage with the outer side of the roll facing up. A bladed rotor is pressed from above with a pressing pressure of 100mN, then rotated at a speed of 2.0 revolutions per second. The vibration of the sample stage is measured with a vibration sensor. The TS750 outer surface, which is the intensity of the first maximum peak in the spectrum seen from the low frequency side (TS750 value), is 12dBV. 2 rms over 30dBV 2 is less than or equal to rms, Using the tissue softness measuring device TSA, a toilet paper sample was placed on a sample stage with the inner side of the toilet roll facing up, and a bladed rotor was pressed from above with a pressing pressure of 100 mN, then rotated at a speed of 2.0 revolutions per second. The vibration of the sample stage was measured with a vibration sensor, and the intensity of the first maximum peak in the spectrum seen from the low frequency side (TS750 value) was obtained. The TS750 inner surface, which is the TS750 value, was greater than the TS750 outer surface. Toilet paper is A first bonding embossment for defining a bonding area where two sheets are in close contact with each other; a second bonding embossed portion for defining a bonding area in cooperation with the first bonding embossed portion such that the two sheets are in close contact with each other, and for integrally bonding the two sheets together with the first bonding embossed portion; A method for producing toilet paper comprising: The method includes a forming step of forming a two-ply toilet paper by overlapping two sheets, and rolling the formed two-ply toilet paper by a predetermined length at a predetermined roll diameter. To achieve the specified winding density A winding step of winding the film into a roll, The forming process is TS750 outer surface 12dBV 2 rms over 30dBV 2rms or less, and the inside of the TS750 is larger than the outside of the TS750. (1) A non-embossing process in which two sheets of different paper quality are used and the two sheets are overlapped without embossing the entire surface of each of the two sheets; (2) A double embossing process in which two sheets of the same or different paper quality are used, and the entire surface of each of the two sheets is embossed under different embossing conditions before the two sheets are superimposed; (3) A single embossing process in which two sheets of the same or different paper quality are used, the two sheets are stacked together, and the entire surfaces of the two sheets are embossed at the same time. A first step selected from the following: a second step of performing a bonding embossing process after the first step, which forms a first bonding embossed portion for defining a bonding area where the two sheets are in close contact with each other, and a second bonding embossed portion for integrally bonding the two sheets together with the first bonding embossed portion and defining a bonding area where the two sheets are in close contact with each other together, A method for producing a toilet roll, comprising: Effect of the Invention

[0012] According to the present invention, it is possible to provide a toilet roll which has a long winding length per roll, which allows for space saving during transport and storage, has an excellent feel, and prevents the toilet paper from rewinding. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is an external view showing an example of the configuration of a toilet roll according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic cross-sectional view of the tissue softness measuring device TSA. [Diagram 3] 2 is a schematic cross-sectional view of an example of a sample measured by the measuring device TSA. [Figure 4] FIG. 2 is a diagram illustrating the measurement principle of the measurement device TSA. [Diagram 5] FIG. 2 is a diagram illustrating the measurement principle of the measurement device TSA. [Figure 6] FIG. 13 is a diagram showing an example of a measurement result obtained by the measurement device TSA. [Figure 7] FIG. 1 is a schematic diagram showing an example of a manufacturing facility applicable to the manufacture of toilet rolls. [Figure 8] FIG. 1 is a diagram illustrating how to rewind toilet paper. [Figure 9] 1A to 1C are diagrams showing examples of the structure of a bonding embossed portion. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] (Embodiment) The toilet roll according to the embodiment of the present invention will be described with reference to the drawings. The following embodiments and drawings are provided for illustrative purposes and are not intended to limit the present invention.

[0015] (Toilet roll) FIG. 1 is a schematic external view illustrating an example of the configuration of a toilet roll according to an embodiment of the present invention.

[0016] Referring to FIG. 1, a toilet roll 10 according to an embodiment of the present invention is a so-called two-ply toilet paper 13, consisting of two overlapping sheets 11 and 12, wound into a roll by a predetermined length around a paper tube 14, which is a cylindrical core.

[0017] (Sheet) Each of the two sheets 11, 12 that are components of the toilet paper 13 is obtained by papermaking a slurry containing a pulp component, which is a fiber raw material. The two sheets 11, 12 may be sheets of the same or different paper quality.

[0018] (Pulp component) Pulp components include wood pulp, non-wood pulp, and waste paper pulp.

[0019] Examples of wood pulp produced using wood as a raw material include chemical pulps such as hardwood pulp (hardwood kraft pulp (LKP)), softwood pulp (softwood kraft pulp (NKP)), sulfite pulp (SP), dissolving pulp (DP), soda pulp (AP), unbleached kraft pulp (UKP), and oxygen bleached kraft pulp (OKP). Other examples include semi-chemical pulps such as semi-chemical pulp (SCP) and chemi-ground wood pulp (CGP), groundwood pulp (GP), and thermomechanical pulp (TMP, BCTMP), but are not limited thereto.

[0020] Non-wood pulps produced using plants or animals other than wood as raw materials include, but are not limited to, cotton pulps such as cotton linters and cotton lint, non-wood pulps such as hemp, wheat straw, and bagasse, and cellulose, chitin, and chitosan isolated from sea squirts and seaweed.

[0021] Examples of waste paper pulp produced using waste paper (pulp produced from papermaking) as a raw material include so-called milk carton pulp, which is made from paper cartons for filling and packaging liquids, such as milk cartons, and deinked pulp, which is made from newspapers, magazines, etc., but is not particularly limited to these.

[0022] The pulp component may be one of the above-mentioned types, or may be a mixture of two or more types. These pulp components greatly affect the quality of the toilet paper 13, so they are appropriately blended in a predetermined type and blending ratio according to the required quality.

[0023] For example, only wood pulp (100% by mass) can be used as the pulp component. At least one selected from coniferous pulp and hardwood pulp can be preferably used as the wood pulp. Coniferous pulp has long and strong fibers, and can impart strength to the sheet produced. Hardwood pulp has short and flexible fibers, and can provide uniformity, good texture, softness, and the like to the sheet produced. In an embodiment of the present invention, it is preferable to use coniferous pulp and hardwood pulp in combination, and it is more preferable to use coniferous kraft pulp (NKP) and hardwood kraft pulp (LKP) in combination.

[0024] When softwood pulp and hardwood pulp are used in combination, the L / N ratio, which indicates the blending ratio (mass ratio) of softwood pulp to hardwood pulp, is, for example, preferably 10 / 90 to 90 / 10, more preferably 20 / 80 or more, even more preferably 30 / 70 or more, and more preferably 80 / 20 or less, and even more preferably 70 / 30 or less.

[0025] (optional ingredient) Various chemicals may be added to the sheets 11 and 12 as optional components to achieve the required quality and stabilize operation. Examples of optional components include dry strength agents, wet strength agents, softeners, bulking agents, dyes, fragrances, dispersants, drainage improvers, pitch control agents, retention improvers, sizing agents, and the like. Examples of dry strength agents include cationic starch, polyacrylamide (PAM), carboxymethyl cellulose (CMC), and the like. Examples of wet strength agents include polyamide epichlorohydrin, urea, melamine, thermally crosslinked polyacrylamide, and the like. Examples of softeners include anionic surfactants, nonionic surfactants, cationic surfactants, and zwitterionic surfactants, and the like. The above optional components may be used alone or in combination of two or more.

[0026] In the embodiment of the present invention, the types (paper quality such as material and physical properties) of the two sheets 11, 12 to be overlapped with each other may be the same or different depending on the required quality and the like.

[0027] One end (starting end) of the toilet paper 13 is adhered and fixed to the outer periphery of the paper tube 14 by pick-up glue (adhesive) (not shown). This makes it possible for the toilet paper 13 to be wound around the paper tube 14 when the toilet roll 10 is manufactured, and also prevents the toilet paper 13 from peeling off and becoming detached from the paper tube 14 in the toilet roll 10.

[0028] (Paper tube) The cardboard tube 14 has a cylindrical shape, around which the toilet paper 13 is wound to form the toilet roll 10. The inner diameter of the cardboard tube 14 is set according to the size of the components (core, hooks, etc.) of the toilet roll holder that support the rotation of the toilet roll 10. For example, the inner diameter according to the Japanese Industrial Standards JIS is 38 mm (±1 mm), and the core diameter DC, which is the outer diameter of the cardboard tube 14, depends on the thickness of the cardboard tube 14, but is generally around 38 mm to 40 mm.

[0029] The material of the cardboard tube 14 may be any material that can be applied to its outer circumferential surface, pick up and glue the beginning end of the toilet paper 13, and wind the toilet paper 13, and is often made of cardboard such as cardboard tube base paper, cardboard base paper, or kraft paper. The cardboard tube 14 may be made of a strip of paper wound in a spiral shape, for example.

[0030] (Pickup glue) The pick-up glue is an adhesive for adhering and fixing the beginning end of the toilet paper 13 to the outer circumferential surface of the paper tube 14. The type of adhesive is not particularly limited, but it is preferable that the adhesive is capable of quickly adhering and fixing the toilet paper 13 and has an adhesive strength that can withstand the tensile force when the toilet paper 13 is wound up. As such an adhesive, a water-soluble adhesive is preferable, and a cellulose derivative adhesive is more preferable. Among commercially available cellulose derivative adhesives, for example, Kanebinol TV976 and Kanebinol TV986 (both trade names, manufactured by Nippon NSC Co., Ltd.) are preferably used because they have strong wet tack and excellent pick-up properties.

[0031] (Toilet roll length) In an embodiment of the present invention, the wound length of the toilet roll 10, which is the length of the toilet paper 13 wound around the paper tube 14, is 33 m or more and 100 m or less. The wound length can be determined, for example, by actually measuring the length of the toilet paper 13 while unwinding it from the toilet roll 10.

[0032] When the roll length of the toilet roll 10 is within this range, the length of the toilet paper 13 per roll is long, making it possible to save space when carrying or storing the toilet roll 10. When the roll length of the toilet roll 10 exceeds 100 m, the roll diameter of the toilet roll 10 generally becomes large, making it difficult for the toilet roll 10 to fit into a typical toilet roll holder. Also, when the roll length of the toilet roll 10 is less than 33 m, the roll length per roll is short, making it difficult to save space when carrying or storing the toilet roll 10.

[0033] (Toilet roll diameter) In an embodiment of the present invention, the roll diameter DR of the toilet roll 10, which is the roll diameter of the toilet paper 13 wound into a roll, is 100 mm or more and 134 mm or less. The roll diameter DR can be measured using, for example, a vernier caliper.

[0034] When the roll diameter DR of the toilet roll 10 is within this range, the toilet roll 10 can be accommodated in a general toilet roll holder and can be supported therein so as to be freely rotatable. When the roll diameter DR of the toilet roll 10 is larger than 134 mm, the toilet roll 10 is difficult to accommodate in a general toilet roll holder. Also, when the roll diameter DR of the toilet roll 10 is smaller than 100 mm, the roll length of the toilet roll 10 is limited, making it difficult to save space during transport and storage by increasing the roll length. Also, when attempting to ensure a long roll length of the toilet roll 10 with a small roll diameter DR, the paper thickness and bulkiness of the toilet paper 13 and the basis weight of the constituent sheets 11 and 12 are limited, making it difficult to ensure a good feel in use and strength.

[0035] (Toilet roll density) The winding density of the toilet roll 10 is calculated according to the following formula (I).

[0036] (Winding density) = (Winding length x Number of plies) ÷ (Cross-sectional area of ​​toilet roll) (Formula I)

[0037] The cross-sectional area of ​​the toilet roll 10 corresponds to the area of ​​the portion of the side of the toilet roll 10 shown in Fig. 1(b) that is composed of the toilet paper 13. In other words, the cross-sectional area of ​​the toilet roll 10 is the area of ​​a circle whose diameter is the winding diameter DR minus the area of ​​a circle whose diameter is the core diameter DC of the paper tube 14. The cross-sectional area of ​​the toilet roll 10 is calculated by the following formula (II).

[0038] (Cross-sectional area) = (Toilet roll diameter DR ÷ 2) 2 ×3.14-(Core diameter DC÷2) 2 ×3.14 (Formula II)

[0039] For example, if the toilet roll 10 has a roll length of 37.5 m, a roll diameter DR of 117 mm, and a core diameter DC of the paper tube 14 of 40 mm, the toilet paper 13 has two plies, so the roll density is (37.5 m × 2) ÷ {(117 mm ÷ 2) 2×3.14-(40mm÷2) 2 × 3.14} to get 0.79 m / cm 2 It becomes.

[0040] (toilet paper) The toilet paper 13 is a so-called two-ply toilet paper, and has the form of a laminated sheet in which two sheets 11 and 12 are overlapped.

[0041] (grammage per sheet) In the embodiment of the present invention, the basis weight of each of the two sheets 11 and 12 constituting the toilet paper 13 is 11 g / m 2 More than 16g / m 2 The basis weight per sheet can be calculated by measuring the basis weight of the two-ply toilet paper 13 and dividing the basis weight by 2, the number of plies, in accordance with the provisions of Japanese Industrial Standard JIS P8124. That is, the two-ply toilet paper 13 is conditioned according to the method specified in Japanese Industrial Standard JIS P8111, and the conditioned two-ply toilet paper 13 is cut into a predetermined size, for example, 10 cm x 10 cm, while the two sheets 11, 12 are still stacked, and the weight of the cut-out two-ply toilet paper 13 is measured, and the weight is multiplied by 0.01 m of the cut-out area of ​​the two-ply toilet paper 13. 2 The basis weight of the two-ply toilet paper 13 is measured by dividing the basis weight by 2, the number of plies, to obtain the basis weight per sheet.

[0042] The basis weight per sheet is 11g / m 2 If it is less than this, the strength will be low and the feeling of use will be poor due to the reduced water absorption, etc. The basis weight per sheet is 16 g / m 2If the thickness exceeds this range, the paper will generally become thicker and the roll diameter of the toilet roll 10 will become larger. If the roll diameter of the toilet roll 10 is to be kept within the above range, it will be difficult to ensure the roll length of the toilet roll 10. Furthermore, if a roll length within the above range is to be obtained, it will be necessary to reduce the thickness of the sheets 11, 12, which may cause the sheets 11, 12 to become crushed and the texture of the toilet paper 13 to be impaired.

[0043] In the embodiment of the present invention, the toilet paper 13 is characterized in that a joining embossing process is applied to a partial area of ​​the sheet for the purpose of joining two sheets constituting two plies.

[0044] In addition, in the embodiment of the present invention, the toilet paper 13 may be an embossed product in which the entire sheet (entire surface area) is embossed for the purpose of imparting a pattern or changing the feel to improve the texture, or may be a non-embossed product that is not embossed. If the toilet paper 13 is an embossed product, the embossing specification may be a so-called single embossing or a so-called double embossing. The embossing and the joining embossing will be described below.

[0045] (Embossed) Embossing refers to a process in which an embossed convex portion is formed on one of the two surfaces of a sheet to be embossed, and an embossed concave portion formed by the back side of the embossed convex portion is formed on the other surface. Embossing can be performed by a known method. For example, embossing may be performed by a "matched" embossing roll in which a male (convex) embossing roll and a female (concave) embossing roll of approximately complementary shapes mesh together, or by a so-called "mismatched" embossing roll in which the male (convex) embossing roll and the female (concave) embossing roll are not identical in shape and apply a shear force to the sheet when they mesh together, or by a male (convex) embossing steel roll and a plain rubber roll.

[0046] (1) Embossing the entire sheet (entire surface area) The embossing in one embodiment of the present invention shown in Fig. 1 is a so-called single embossing. That is, in toilet paper 13, its constituent sheets 11 and 12 are stacked on top of each other and then embossed as a whole. In the example of Fig. 1, toilet paper 13 has a large number of embossed portions 13a that protrude toward the inside of the roll formed in a repeating pattern across the entire surface (whole surface) of the paper.

[0047] In this manner, in this embodiment, the embossed portion 13a is protruded on the inner surface side of the toilet paper 13, which is the surface that faces the inside of the roll, and an embossed recess is provided on the outer surface side of the toilet paper 13, which is the surface that faces the outside of the roll, making the outer surface of the toilet paper 13 smooth to the touch while making the inner surface less smooth.

[0048] In the embodiment of the present invention, the pattern of the embossed portion may be any pattern other than those described above. For example, in one aspect of the embodiment of the present invention, the pattern of the embossed portion may be a so-called double embossed pattern. That is, in the toilet paper 13, each or one of the sheets 11 and 12, which are the components of the toilet paper 13, may be embossed in its entirety before being superimposed on each other.

[0049] In one embodiment of the present invention, the sheets 11 and 12 that are components of the toilet paper 13 may not be embossed in their entirety. In other words, the toilet paper 13 may be a non-embossed product in which no repeating pattern is formed over the entire surface of the paper.

[0050] (2) Embossing for bonding In an embodiment of the present invention, in order to prevent the sheets 11 and 12 constituting each layer of the toilet paper 13 from peeling off from each other from the viewpoint of preventing rewinding of the toilet roll 10, the toilet paper 13 is provided with a bonding embossed portion (for example, the embossed portion 13e (11e, 12e) in (a) of FIG. 1) for bonding the constituent sheets 11 and 12 to each other. The bonding embossed portion 13e (11e, 12e) defines a bonding area for integrally bonding the sheets 11 and 12. The bonding embossed portion 13e (11e, 12e) may be formed in a repeating pattern on both side edges of the width direction (CD direction) of the toilet paper 13 so as to extend along its longitudinal direction (MD direction), and when formed in this manner, it is also called an edge embossment. The bonding embossed portion 13e (11e, 12e) may be formed so as not to protrude outward in the thickness direction from both the front and back sides of the toilet paper 13.

[0051] 9 is a diagram showing an example of the structure of the joining embossed portion 13e (11e, 12e). Referring to (a) of FIG. 9, the toilet paper 13 includes a first joining embossed portion 11e for defining a joining area where the two sheets 11, 12 constituting the two plies are in close contact with each other, and a second joining embossed portion 12e for defining a joining area where the two sheets 11, 12 are in close contact with each other together with the first joining embossed portion 11e and for integrally joining the two sheets 11, 12 together with the first joining embossed portion 11e. By joining the two sheets 11, 12 together with the joining embossed portion, peeling of the two sheets 11, 12 is prevented, and therefore rewinding of the toilet roll can be prevented.

[0052] FIG. 9(b) shows a pair of metallic embossing rolls 16 and 17 used to form the joining embossed portion 13e (11e, 12e) shown in FIG. 9(a).

[0053] Fig. 9(c) shows another example of the bonding embossed portions 11e, 12e formed by a pair of metal embossing rolls 16, 17 shown in Fig. 9(b). As shown in Fig. 9, even when the same processing rolls are used, bonding embossed portions of various patterns can be formed depending on the processing conditions, and thus the texture and appearance of the bonding embossed portion areas can be made different.

[0054] (TS750 value obtained by tissue softness measuring device TSA) In an embodiment of the present invention, the TS750 values ​​obtained by a tissue softness measuring device TSA (hereinafter, also simply referred to as the measuring device TSA) are specified for both sides of the toilet paper 13. Before describing the specific range of the TS750 value according to the embodiment of the present invention, the tissue softness measuring device TSA, the measurement principle, and the measurement procedure used to obtain the TS750 value will be described with reference to Figs. 2 to 6.

[0055] (Tissue Softness Measurement Device TSA) 2 is a schematic cross-sectional view of a tissue softness measuring device TSA manufactured by Emtec Electronic GmbH, Germany, which can be used to obtain a TS750 value according to an embodiment of the present invention. The measuring device TSA is available from Nippon Luft Co., Ltd. (a distributor in Japan).

[0056] The human feel (touch) when touching toilet paper 13 is affected by three characteristics of toilet paper 13: "softness," "smoothness / roughness," and "rigidity." The measuring device TSA is a device that can quantify the parameters (referred to as TS7, TS750, and D, respectively) that are indicators of these three characteristics through acoustic measurement and deformation measurement. The measuring device TSA can calculate a value called the hand feel (HF) value by performing an analysis using an algorithm based on these obtained parameters (raw data) and the basis weight, thickness, number of plies, etc. of the toilet paper 13. The HF value is a value used for a comprehensive quantitative evaluation of the touch of toilet paper 13, which is correlated with the results of human touch (panel test).

[0057] Of the parameter values ​​mentioned above, TS7 (softness), TS750 (smoothness / roughness), and D (stiffness), the TS7 and TS750 values ​​can be obtained by acoustic measurement using the tissue softness measuring device TSA.

[0058] (Principle of Acoustic Measurement by Tissue Softness Analyzer TSA) The measurement principle of acoustic measurement by the tissue softness measuring device TSA will be described with reference to Figs.

[0059] FIG. 3 is a schematic cross-sectional view showing an example of a sample of toilet paper 13 to be measured by the tissue softness measuring device TSA. In an embodiment of the present invention, the sample 23 to be measured by the measuring device TSA 20 is a two-ply toilet paper 13 consisting of two sheets 11 and 12, but in FIG. 3, the sample 23 is shown generally as a single sheet. The sample 23 has an uneven texture. In addition, the surface of the sample 23 has raised naps, which are protruding portions originating from the constituent fibers 23f. Raised naps are also called fiber fluff, and the roots of the raised fibers are present on the surface or inside of the sample 23.

[0060] 2(a), in the tissue softness measuring device TSA 20, a vibration sensor 21a is provided inside a sample stage 21, and a bladed rotor 25 that rotates a blade 25a by a motor 25b is provided above the sample stage 21. The sample 23 is attached to the sample stage 21 like a drum head, with the surface to be measured facing upwards, i.e., with the measurement surface facing the bladed rotor 25.

[0061] In the first measurement step, the bladed rotor 25 is moved vertically downward, and the blade 25a presses the specimen 23 with a set load, as shown in FIG. 2(b). Then, at the constant vertical position, the blade 25a is rotated at a set speed. The horizontal movement of the blade 25a on the specimen 23 caused by this generates different types of vibrations and noises. The generated vibrations and noises are detected by the vibration sensor 21a. The detected vibrations and noises are analyzed for frequency using a PC to obtain the TS750 value. For example, by using the emtec measurement system, which is software from Emtec, the TS750 value can be automatically obtained on the software.

[0062] In detail, referring to Fig. 4, during measurement by the measuring device TSA 20, the blade 25a is moved horizontally at a constant vertical position, as illustrated by the movement from position (1) to (3) in the figure. Such horizontal movement of the blade 25a causes the position of the sample 23 to vary, inducing vertical vibration of the sample 23. The induced vibration frequency depends on the structural dimensions of the toilet paper 13 (e.g. dimensions resulting from creep, embossment, etc.) and the rotation speed of the blade 25a. The amplitude (strength) of the vibration depends on the height of the structure.

[0063] 5, during the above-mentioned measurement by the measuring device TSA 20, the blade 25a, which is moved horizontally at a constant vertical position, advances horizontally on the surface of the sample 23, as exemplified by the movement from position (i) to (iii) in the figure. At this time, the blade 25a is momentarily interrupted by contact with the fiber 23f protruding from the sample surface, and due to the vibration of the blade 25a, horizontal vibration of the blade 25a itself is induced.

[0064] In comparison with FIG. 5(a), in FIG. 5(b), the fiber 23f is soft, and when the blade 25a and the fiber 23f come into contact, the fiber 23f bends significantly and the blade 25a bends less, so the amplitude of the induced horizontal vibration of the blade 25a is relatively small. The amplitude of the horizontal vibration of the blade 25a depends on the softness and hardness of the fiber 23f (the rigidity of each fiber), the internal structure of the material of the sample 23 (bulk, fiber bond strength), micro and macro compressibility, additive chemicals (softener, starch, dry strength agent), etc. The resonant frequency is constant depending on the material and geometric dimensions of the sample 23, and is approximately 6,500 Hz.

[0065] FIG. 6 shows an example of a frequency spectrum obtained as a result of acoustic measurement by the measurement device TSA 20. The horizontal axis is frequency (unit: Hz) and the vertical axis is amplitude (intensity) (unit: dBV 2 The resulting spectrum generally consists of two overlapping single spectra.

[0066] The single spectrum based on the vertical vibration of sample 23, as described with reference to Figure 4, appears as the first maximum peak P1 in the spectrum viewed from the low frequency side. The intensity (amplitude) of maximum peak P1 is the TS750 value, which is an index of the "smoothness / roughness" of sample 23. The smaller the TS750 value, the smoother the sample 23 is evaluated to be.

[0067] 5, the single spectrum based on the horizontal vibration of the blade 25a appears as a maximum peak P2 in the spectrum including (around) 6500 Hz, which is the resonant frequency. The intensity (amplitude) of the maximum peak P2 is the TS7 value, which is an index of the "softness" of the sample 23. The smaller the TS7 value, the softer the sample 23 is evaluated to be.

[0068] In addition, in the measuring device TSA 20, as a second measurement step, a D value representing the "rigidity" of the sample 23 can be obtained by measuring the deformation by repeating a cycle of changing the load applied to the sample 23. A hand feel (HF) value can be obtained by a nonlinear algorithm from the obtained D value, the above-mentioned TS7 value and TS750 value, the paper thickness, basis weight, number of plies, etc. These D value and HF value are not numerical values ​​defined in the embodiment of the present invention, so further explanation of them will be omitted in this specification.

[0069] (TS750 value measurement procedure) Measurement of the TS750 value using the tissue softness measuring device TSA 20 can be performed according to the following procedure.

[0070] (1) Sample preparation The toilet paper 13 is unwound from the toilet roll 10, and a circular toilet paper sample 23 having a diameter of 112.8 mm is cut out. The sample 23 includes a set of two sheets 11, 12 that make up the toilet paper 13. An Emtec sample punch may be used to cut out the sample 23.

[0071] (2) Mounting the sample The sample 23 is placed on the circular sample stage 21 so that the measurement surface of the sample 23 faces upward (i.e., the bladed rotor 25 side). Next, the sample fixing ring 24 is pressed down so as to hold the outer periphery of the sample 23, and the sample 23 is locked onto the sample stage 21.

[0072] (3) Measurement The bladed rotor 25 is pressed onto the sample 23 with a pressing pressure of 100 mN. Next, the motor 25b is operated to rotate the bladed rotor 25 at a rotation speed of 2.0 revolutions per second. The vibration of the sample stage 21 at this time is measured by the vibration sensor 21a installed inside the sample stage. Using software, the vibration frequency is analyzed and the TS750 value is automatically obtained.

[0073] (4) Calculation of the average For 10 toilet rolls of one type, steps (1) to (3) are repeated to perform a total of 10 measurements, and the TS750 value is obtained as the average value.

[0074] (TS750 value) Here, the TS750 value of the toilet roll 10 according to the embodiment of the present invention is defined as follows.

[0075] (TS750 exterior) Using the tissue softness measuring device TSA 20, the toilet paper 13 is placed on the sample stage 21 with the outer side of the toilet roll 10 facing up. The bladed rotor 25 is pressed from above with a pressing pressure of 100 mN, and then rotated at a rotation speed of 2.0 per second. The vibration of the sample stage 21 is measured by the vibration sensor 21a. The TS750 outer surface, which is the intensity of the first maximum peak of the spectrum seen from the low frequency side (TS750 value), is 12 dBV. 2 rms over 30dBV 2 is less than rms.

[0076] TS750 exterior: 12dBV 2 rms over 30dBV 2 When the TS750 outer surface is 12 dBV rms or less, the surface of the toilet paper 13 on the outside of the toilet roll 10 (also called the outer surface of the toilet paper) is smooth and has an excellent texture. 2 If the rms is less than 30 dBV, the toilet paper 13 will have a slippery texture, which is undesirable for its texture, and manufacturing will be difficult. 2If it is greater than rms, the outer surface of the toilet paper 13 will not be sufficiently smooth, and a good texture will not be obtained.

[0077] (Difference D (TS750 inner surface - TS750 outer surface)) Using the tissue softness measuring device TSA 20, the toilet paper 13 is placed on the sample stage with the inner side of the toilet roll 10 (also called the inner side of the toilet paper) facing up, and the bladed rotor 25 is pressed from above with a pressing pressure of 100 mN against the toilet paper 13, which is then rotated at a rotation speed of 2.0 per second. The vibration of the sample stage 21 is measured by the vibration sensor 21a, and the difference D (TS750 inner side - TS750 outer side) between the TS750 inner side, which is the intensity of the first maximum peak of the spectrum seen from the low frequency side (TS750 value), and the above-mentioned TS750 outer side is 0 dBV. 2 rms. That is, the TS750 inner surface is larger than the TS750 outer surface. This means that the inner surface of the toilet paper 13 is rougher than the outer surface of the toilet paper 13.

[0078] Above mentioned TS750 external surface (12dBV 2 rms over 30dBV 2 rms or less), the difference D (TS750 inner surface - TS750 outer surface) is 0 dBV 2 When the smoothness is equal to or less than rms, the inner surface of the toilet paper 13 is as smooth as or smoother than the outer surface of the toilet paper 13. In this case, the texture of the inner surface as well as the outer surface of the toilet paper is improved, but the inner sheet and the outer sheet of the two-ply toilet paper 13 are slippery, and the two-ply toilet paper 13 peels off when the toilet paper 13 is pulled out from the toilet roll 10, which makes it easy for the toilet roll 10 to rewind.

[0079] On the other hand, the above-mentioned TS750 outer surface (12 dBV 2 rms over 30dBV 2 rms or less), and the difference D (TS750 inside surface - TS750 outside surface) is 0 dBV2 When the rms is larger, the toilet paper 13 has a moderately smooth outer surface with an excellent texture, and the inner surface is rougher than the outer surface, so that the inner sheet and the outer sheet of the two-ply toilet paper 13 do not slide easily, and peeling of the two-ply toilet paper 13 is suppressed when the toilet paper 13 is pulled out from the toilet roll 10, and as a result, rewinding of the toilet roll 10 is suppressed.

[0080] (Examples of manufacturing methods and manufacturing equipment applicable to embodiments of the present invention) An example of a method and equipment applicable to manufacturing a toilet roll according to an embodiment of the present invention will be described with reference to Figures 1 and 7. The toilet roll 10 can be manufactured, for example, as follows.

[0081] (Manufacture of raw rolls) Raw rolls 11R, 12R are manufactured to manufacture the sheets 11, 12, which are the components of the toilet paper 13. In detail, a papermaking machine (not shown) is used to make and wind wide (several times to twenty-odd times the width of the toilet roll) and long sheets 11L, 12L from a papermaking slurry (paper material), to manufacture the raw rolls 11R, 12R on which the sheets 11L, 12L are wound. As the papermaking machine, for example, a known papermaking machine such as a twin wire former, a cylinder former, a suction pressed former, or a crescent former can be used.

[0082] The papermaking machine may be equipped with a creping section that performs creping. In the creping section, during the drying of the sheet (web) to be made in the raw roll manufacturing process, a creping doctor can give the sheet very fine wavy wrinkles called crepes as necessary. Creping can give the sheet softness, bulkiness (bulk feeling), absorbency, aesthetic appearance (crepe shape), and good touch.

[0083] The papermaking machine may also include a calendar section. In the calendar section, the dried sheet may be subjected to a calendaring process, in which the sheet is sandwiched and pressed from above and below by a pair of calendar rolls, as necessary. This compresses the sheets 11L and 12L, adjusting and equalizing the paper thickness, and smoothing the surface. The calendaring process suppresses protrusions (fuzzing) caused by fibers on the sheet surface, and generally reduces softness. The calendaring section may be provided separately from the papermaking machine, and the calendaring process may be performed in any manufacturing process after the raw roll manufacturing process. The calendaring process may be performed in multiple stages.

[0084] (Toilet roll manufacturing) The raw rolls 11R and 12R are used to manufacture toilet rolls. The raw rolls 11R and 12R may be manufactured according to the above-mentioned manufacturing method for raw rolls, or manufactured raw rolls 11R and 12R may be obtained by purchase or the like, and there is no particular limitation on the method for preparing the raw rolls 11R and 12R. Fig. 7 is a schematic diagram showing an example of a manufacturing facility applicable to the manufacture of toilet rolls according to an embodiment of the present invention. Fig. 7 is for illustrative purposes only and does not limit the present invention.

[0085] The raw web roll 11R and the raw web roll 12R are rotatably attached to a raw web roll stand 70, and are rotated and driven by a raw paper sheet payout device (not shown) to pay out the sheets 11L and 12L. The sheets 11L and 12L may be of the same or different paper quality.

[0086] The sheets 11L and 12L unwound from the original rolls 11R and 12R are transported to an embossing section 76 disposed downstream of the original roll stand 70. Downstream of the embossing section 76, a winding section 77 and an end processing section 78 are further disposed in this order.

[0087] The embossing section 76 is, in short, a unit that embosses the sheets 11L and 12L to form embossed sheets.

[0088] The embossing section 76 includes two pairs of embossing roll units 71 and 72 and one bonding embossing roll unit 75 .

[0089] Each of the embossing roll units 71 and 72 has an embossing roll and a backup roll. The embossing roll of the embossing roll unit 71 is rotatable, and the outer peripheral surface of the embossing roll is formed with uneven portions corresponding to the embossing pattern of the first embossed portion 11a of the sheet 11 shown in Fig. 1. Similarly, the embossing roll of the embossing roll unit 72 is rotatable, and the outer peripheral surface of the embossing roll of the embossing roll unit 72 is formed with uneven portions corresponding to the embossing pattern of the second embossed portion (not shown) of the sheet 12 shown in Fig. 1.

[0090] On the upstream side of the embossing roll units 71, 72, two rotatable guide rollers 73, 74 for guiding the sheets 11L, 12L corresponding to the embossing roll units 71, 72, respectively, are provided.

[0091] In the manufacturing apparatus shown in FIG. 7, the embossing section 76 is configured to be able to selectively perform (i) single embossing, (ii) double embossing, or (iii) no embossing, depending on the paper path of the sheets 11L, 12L and the presence or absence of pressing by the embossing roll units 71, 72.

[0092] (i) Single embossing FIG. 7 shows an example of the paper path of the sheets 11L, 12L when single embossing is performed. When single embossing is performed, the sheets 11L, 12L fed from the original rolls 11R, 12R are both wrapped around a guide roller 73, overlapped, and guided toward the embossing roll unit 71. The embossing roll unit 71 includes an embossing roll and a backup roll arranged to be movable along the direction facing the embossing roll, and the overlapped sheets 11L, 12L are inserted between them. As a result of the backup roll being pressed against the outer circumferential surface of the embossing roll with a predetermined pressure, the sheets 11L, 12L passing between them are commonly embossed. In this case, sheets of the same or different paper quality can be used as the sheets 11L, 12L. As a modified example, a single original roll on which the sheets 11L and 12L are previously overlapped and wound may be used, and the sheets 11L and 12L may be unwound from the original roll in an overlapped state and wound around the guide roller 73.

[0093] (ii) Double embossing When performing double embossing, the sheet 11L unwound from the original roll 11R is wound around a guide roller 73 and guided toward the embossing roll unit 71, and is inserted between the embossing roll and the backup roll of the embossing roll unit 71. Similarly, the sheet 12L unwound from the original roll 12R is wound around a guide roller 74 and guided toward the embossing roll unit 72. The embossing roll unit 72 includes an embossing roll and a backup roll arranged to be movable along the direction facing the embossing roll, and the sheet 12L is inserted between them. Each backup roll is pressed against the outer circumferential surface of the corresponding embossing roll with a predetermined pressure, and the sheets 11L and 12L passing between them are embossed. In this case, sheets of the same or different paper quality can be used as the sheets.

[0094] (iii) No embossing In the case of so-called no embossing, in which the sheets 11L and 12L are not embossed over the entire surface (whole surface), the sheets 11L and 12L are passed through the same paper passing path as either the double embossing or single embossing, but the backup roll is not pressed against the outer circumferential surface of the embossing roll in the embossing roll unit. In this case, sheets of different paper quality are used as the sheets 11L and 12L.

[0095] (Embossing for joining) A bonding embossing roll unit 75 is disposed downstream of the embossing roll units 71 and 72. The bonding embossing roll unit 75 has an embossing wheel and a backing roll that face each other. The backing roll is rotatable so as to rotate synchronously with the embossing rolls of the embossing roll units 71 and 72, and an embossing pattern corresponding to the bonding embossing portion is formed on the outer circumferential surfaces of the embossing wheel and the backing roll.

[0096] The sheets 11L and 12L that have passed through the embossing roll unit are passed between the embossing wheel and the backing roll of the bonding embossing roll unit 75 in a mutually overlapping state, and are wound around the backing roll. At this time, as necessary, the embossing wheel is pressed against the rotating backing roll with a predetermined pressure by a fluid pressure cylinder, whereby the laminate of the sheets 11L and 12L is embossed for bonding, and a bonding embossed portion for preventing peeling is provided.

[0097] In an embodiment of the present invention, the joining embossed portion is provided for the purpose of preventing peeling of two sheets in a two-ply toilet paper.

[0098] In this example, at least the uneven portions of the embossing rolls of the embossing roll units 71 and 72 and the joining embossing roll unit 75 are formed of metal, while the surface portion of the backup roll is formed of a hard rubber-like elastic material such as elastically deformable hard synthetic rubber.

[0099] By performing the embossing process using a male (convex) embossing steel roll and a plain rubber roll, it is possible to make the texture of one surface of the embossed sheet significantly different from that of the other surface. For example, in the embossed convex portion formed by the embossing steel roll, the nap of the sheet surface based on the constituent fibers of the sheet is crushed by contact with the plain rubber roll, reducing softness and increasing smoothness.

[0100] The wide toilet paper 13L formed by the sheets 11L and 12L laminated in the embossing section 76 is sent to a winding section 77 disposed downstream thereof.

[0101] In the winding section 77, the tip of the toilet paper 13L delivered from the embossing section 76 is wound around a wide (i.e., axially long) paper tube 14L, which serves as a roll core, via adhesive (pickup glue).

[0102] The toilet paper 13L is wound up to a predetermined length around the paper tube 14L to form a roll 86 that will become a wide toilet roll 10L (i.e., a large dimension in the CD direction), and the end of the toilet paper 13L is cut off by a cutting means (not shown). The resulting roll 86 is sent to the end processing section 78.

[0103] The end processing section 78 glues the end of the end of the roll 86 sent out from the winding section 77 to the surface (outer peripheral surface) of the roll 86 with an adhesive (tail seal glue) to form a wide toilet roll 10L, preventing the wide toilet roll 10L from unraveling.

[0104] In addition, prior to cutting the toilet paper 13L at the winding section 77 at predetermined lengths, tearing perforations that traverse the width direction of the toilet paper 13L may be formed at regular intervals along the longitudinal direction (MD direction) of the toilet paper 13L. Any known perforation forming means can be used to form the tearing perforations. However, the formation of such tearing perforations is optional and not essential in the embodiment of the present invention.

[0105] The wide toilet roll 10L is then conveyed from the end processing section 78 to a cutting section (not shown) where it is cut to a predetermined width according to the product specifications, etc., into individual toilet rolls 10.

[0106] Meanwhile, in the winding section 77, the tip end of the toilet paper 13L (i.e., the end of the toilet paper 13L on the original roll 11R, 12R side) produced by cutting the toilet paper 13L every predetermined length is wound, via adhesive, around a new long winding core in the axial direction arranged in the winding section 77, so that the toilet paper 13L is again wound around the long winding core in the axial direction by a predetermined length.

[0107] The formed log of wide toilet roll 10L is then subjected to a cutting process by a cutting means (not shown) and cut to a predetermined width (product width of the toilet roll) to manufacture the toilet roll 10.

[0108] The above-mentioned manufacturing method and manufacturing device are just an example. For example, in winding section 77, instead of roll 86 that becomes toilet roll 10L (i.e., the log for forming toilet roll 10), a roll with a longer winding length may be formed, and this may be loaded as a secondary roll into another device with a winding function such as a winder, and a toilet roll may be manufactured through a process of forming a log of a predetermined length.

[0109] Furthermore, the term "embossing for bonding" may include a bonding state achieved by a processing form such as stamping in which a stamping roll or the like is used to deform the workpiece, in addition to using the above-mentioned embossing roll.

[0110] (Action and effect) According to the two-ply toilet roll 10 having the joining embossment according to the present embodiment, the basis weight per sheet of the two sheets 11 and 12 constituting the two-ply toilet paper 13 is 11 g / m 2 More than 16g / m 2 or less, which ensures appropriate strength and water absorption, while the roll length of the toilet roll 10 is 33 m or more and 100 m or less and the roll diameter is 100 mm or more and 134 mm or less, so that the length of the toilet paper 13 per roll is long, making it possible to save space when carrying and storing.

[0111] In addition, the TS750 value obtained by the tissue softness measuring device TSA 20 for the two-ply toilet paper 13 is 12 dBV for the TS750 outer surface. 2 rms over 30dBV 2 rms or less, and the outer surface of the toilet paper 13 (the surface on the outside of the roll) has excellent texture (smoothness). In addition, at this time, the difference D between the TS750 inner surface and the TS750 outer surface is 0 dBV 2 rms (i.e., the TS750 inner surface is greater than the TS750 outer surface), and the inner surface of the toilet paper 13 (the surface that faces the inside of the roll) has a moderate smoothness (roughness). That is, since the inner surface of the toilet paper 13 is rougher than the outer surface, the inner sheet and the outer sheet of the two-ply toilet paper 13 do not slide easily, and peeling of the two-ply toilet paper 13 when the toilet paper 13 is pulled out from the toilet roll 10 is suppressed, and as a result, rewinding of the toilet roll 10 is suppressed.

[0112] Furthermore, in this embodiment, the toilet paper 13 includes a first bonding embossed portion 11e for defining a bonding area where the two sheets 11, 12 constituting the two plies are in close contact with each other, and a second bonding embossed portion 12e for defining a bonding area where the two sheets 11, 12 are in close contact with each other together with the first bonding embossed portion 11e and integrally bonding the two sheets 11, 12 together with the first bonding embossed portion 11e. By bonding the sheets together with the bonding embossed portion in this manner, the two sheets 11, 12 of the toilet paper are prevented from peeling off when the toilet roll is in use, and the toilet roll can be prevented from rewinding.

[0113] Therefore, according to this embodiment, the two-ply toilet roll 10 can save space when transporting or storing, while also improving the texture (smoothness) of the toilet paper 13 and preventing the toilet roll 10 from rewinding.

[0114] In an embodiment of the present invention, the TS750 values ​​of both sides of the toilet paper 13 (TS750 outer surface and TS750 inner surface) can be controlled by, for example, the single embossing pattern, the size of the embossed protrusions (diameter, mm), the density of the embossed protrusions (pieces / cm 2 ), height of embossed convex part (mm), embossing pressure (gf / cm 2 ) and by appropriately setting the paper thickness and density after application of the embossing pressure.

[0115] In addition, the TS750 value (TS750 outer surface and TS750 inner surface) of the toilet paper 13 is affected by, for example, the creep processing and / or calendar processing when making the sheets 11L and 12L, and the various conditions of the calendar processing when forming the toilet paper 13L (including whether or not processing is performed).

[0116] Second embodiment Next, a second embodiment of the present invention will be described. Unless otherwise specified, the configurations applicable to the above-mentioned embodiments are also applicable to this embodiment.

[0117] In the toilet roll according to the second embodiment, each of the sheets constituting the toilet paper contains wood pulp, and when the content of wood pulp in the sheet is W and the content of recycled paper pulp in the sheet is R, the recycled paper pulp content in the sheet, calculated by the formula R÷(W+R)×100, is equal to or greater than 0% by mass and less than 40% by mass.

[0118] As explained in the first embodiment, in the embodiment of the present invention, the pulp component of the sheet may be one type alone or two or more types may be mixed together. These pulp components have a large effect on the quality of the toilet paper, so they are appropriately mixed in a predetermined type and mixing ratio according to the required quality.

[0119] Wood pulp, which is virgin pulp produced from wood, can provide sheets with strength, flexibility, uniformity, good texture, softness, etc., and is also excellent in terms of whiteness and hygiene.

[0120] On the other hand, wastepaper pulp, which is pulp produced by recycling waste paper, is effective in reducing waste, conserving the energy resources needed to incinerate waste, curbing CO2 emissions from incineration, and conserving forest resources needed to produce wood pulp.

[0121] Therefore, this embodiment mainly contains wood pulp as the pulp component, and also includes an embodiment in which wood pulp and recycled paper pulp are used in combination from the viewpoint of reducing waste and preserving resources.

[0122] Waste paper pulp is manufactured through various necessary processes, such as disintegrating the raw material waste paper (pulp made from paper) in water, rough sorting to remove large foreign objects, deinking to peel off and separate the ink adhering to the pulp, sorting to remove small foreign objects, and bleaching the pulp. These manufacturing processes use mechanical force, gravity, surfactants, chemicals such as bleach, and heat, and sterilization and disinfection are repeated as necessary, with an emphasis on safety and hygiene.

[0123] In this way, the strength of recycled paper pulp is reduced by physical and chemical damage and by wetting and drying during the manufacturing process, and sheets made from such recycled paper pulp generally have lower strength and softness than sheets made from wood pulp.

[0124] Therefore, from the viewpoint of the strength and softness of the sheet to be manufactured, and in turn the toilet paper, there is a suitable upper limit to the blending ratio of recycled paper pulp (the content of recycled paper pulp in the sheet).

[0125] Specifically, in this embodiment, the recycled paper pulp content in the sheet is calculated by the formula R÷(W+R)×100, where W is the wood pulp content in the sheet and R is the recycled paper pulp content in the sheet. The recycled paper pulp content in the sheet is 0% by mass or more and less than 40% by mass.

[0126] When the recycled paper pulp content in the sheet is 0% by mass or more and less than 40% by mass, the sheet can be provided with appropriate strength and softness. When the recycled paper pulp content is 40% by mass or more, the softness of the sheet decreases, and the feeling of using the toilet paper decreases.

[0127] As for recycled paper, so-called milk carton pulp, which is made from paper cartons (milk cartons), is preferably used because it is mainly produced from strong coniferous pulp, has little printing and high whiteness, and the strength and whiteness of the sheets produced are also high.

[0128] (Action and effect) In the second embodiment, the sheet contains wood pulp and recycled paper pulp as pulp components in a predetermined blend ratio according to the required quality, which contributes to waste reduction and resource conservation while ensuring the desired sheet strength and softness.

[0129] In manufacturing a toilet roll according to an embodiment of the present invention, in order to form toilet paper, (1) An embodiment including a no-embossing step in which two sheets of different paper quality are used and the two sheets are overlapped without embossing the entire surface of each of the two sheets; (2) An embodiment including a double embossing process in which two sheets of the same or different paper quality are used, and the two sheets are embossed under different embossing conditions on the entire surface thereof before the two sheets are superimposed; (3) An embodiment including a single embossing step in which two sheets of the same or different paper quality are used, and the two sheets are superimposed and embossed all over the two sheets at once. I have explained that there is.

[0130] Here, the TS750 value is the intensity (amplitude) of the first maximum peak P1 of a single spectrum based on the vertical vibration of the sample, and the amplitude (intensity) depends on the height of the structure. Therefore, as a method for adjusting the values ​​of the TS750 inner surface and the TS750 outer surface to a desired relationship, Regarding embodiment (1), for example, by varying the conditions of creep processing and / or calendar processing when making sheets 11L and 12L, and the conditions of calendar processing when forming toilet paper 13L (including the presence or absence of processing itself), the TS750 values ​​of both sides of toilet paper 13 (TS750 outer surface and TS750 inner surface) can be controlled.

[0131] In the embodiment (2), the TS value of each sheet can be adjusted by varying the conditions of the embossing process performed on each of the two sheets 11 and 12 that make up the toilet paper 13. For example, the embossing pattern formed by the embossing process, the size of the embossed protrusions (diameter, mm), the density of the embossed protrusions (pieces / cm 2 ), height of embossed convex part (mm), embossing pressure (gf / cm 2 ) By appropriately setting the paper thickness and density after the embossing pressure is applied, the TS7 value of both sides of the toilet paper 13 can be controlled by varying the surface texture of each sheet.

[0132] Regarding the embodiment (3), for example, the embossed pattern formed by embossing, the size of the embossed convex parts (diameter, mm), the density of the embossed convex parts (pieces / cm 2 ), the height (mm) of the embossed convex portion, etc. Also, the relationship between the TS7 values ​​on both sides of the toilet paper 13 can be controlled to be different by selecting the type of embossing roll used in the embossing process (for example, whether a male (convex) embossing roll and a female (concave) embossing roll are used, and in that case, whether they are matched or not, or whether a male (convex) embossing steel roll and a plain rubber roll are used), changing the hardness of the embossing roll, the embossing pressure, etc. EXAMPLES

[0133] Using the manufacturing apparatus shown in FIG. 7, toilet rolls were manufactured through the following manufacturing steps. (a) A papermaking slurry (stock) having a pulp composition of 30% by mass of softwood bleached kraft pulp (NBKP):70% by mass of hardwood bleached kraft pulp (LBKP) was used to make a number of sheets, some of which were different in at least one of the following conditions: sheet basis weight, paper thickness, creping conditions, and calendaring conditions. (b) For Examples 1, 2, 4, 5, 8, 10 and Comparative Examples 1 to 5, single embossing was performed. That is, two of the multiple sheets produced were stacked to form one laminated sheet, and the entire surface of the laminated sheet was subjected to single embossing so that one side was embossed concavely and the other side was embossed convexly. The pressure and / or speed used for embossing was varied depending on the sample. (c) For Examples 3, 6, 7, 9, and 11, double embossing was performed. That is, the entire surface of each of two of the sheets produced was embossed with a concave embossing on one side and a convex embossing on the other side, and then the two sheets were stacked together so that the concave embossing was on the outer side to form a single laminated sheet. At this time, the pressure and / or speed used for embossing was varied depending on the sample. (d) Next, for the examples, bonding embossing was applied to both side edges in the width direction (CD) of the laminate sheet so that the bonding embossments extended along the longitudinal direction (MD). (e) The starting end of the laminated sheet was pressed against a paper tube coated with pick-up glue, glued and fixed, and then wound into a roll around the paper tube with the embossed recess facing outside the roll. (f) When the wound length reached a predetermined length, the end of the wound laminate sheet was cut off to obtain a wide toilet roll. (g) A wide toilet roll was cut to a specified width and a toilet roll was produced in which 2 plies of embossed toilet paper were wound into a roll so that the outer surface of the roll had embossed recesses.

[0134] The following measurements and evaluations were carried out for the toilet rolls of Examples 1 to 11 and Comparative Examples 1 to 5. The measurements were carried out by conditioning the samples in an environment conforming to Japanese Industrial Standard JIS P8111 (temperature 23±1°C, humidity 50±2% RH).

[0135] <Measurement> [Toilet roll length [m]] While unwinding the toilet paper from the manufactured toilet roll, the length of the toilet paper wound around the paper tube from the end to the beginning was measured. Measurements were taken in 0.5 m increments and decimals were rounded down.

[0136] [Toilet roll diameter [mm]] The outer diameter of the produced toilet roll was measured with a vernier caliper and rounded off to the nearest whole number.

[0137] [Core diameter of paper tube [mm]] The outer diameter of the paper tube of the manufactured toilet roll was measured with a vernier caliper and rounded off to the nearest whole number.

[0138] [Winding density [m / cm 2 ]〕 It was calculated according to the following formulas (I) and (II).

[0139] (Winding density) = (Winding length x Number of plies) ÷ (Cross-sectional area of ​​toilet roll) (Formula I) (Cross-sectional area) = (Toilet roll diameter DR ÷ 2) 2 ×3.14-(Core diameter DC÷2) 2 ×3.14 (Formula II)

[0140] [Basis weight (per base paper sheet) [g / m 2 ]〕 The basis weight of the base paper sheet used in the manufacture of the toilet roll was measured in accordance with Japanese Industrial Standard JIS P8124.

[0141] [Basis weight (per sheet) [g / m 2 ]〕 The toilet paper was pulled out from the toilet roll, and the basis weight of the two-ply toilet paper was measured according to Japanese Industrial Standard JIS P8124, and divided by 2, the number of plies, to obtain the basis weight per sheet. Specifically, the two-ply toilet paper was conditioned according to the method specified in Japanese Industrial Standard JIS P8111, and the conditioned two-ply toilet paper was cut into a size of 10 cm x 10 cm while the two sheets were still stacked, the weight of the cut two-ply toilet paper was measured, and the weight was multiplied by 0.01 m of the cut area of ​​the two-ply toilet paper. 2 The basis weight of the two-ply toilet paper was measured by dividing the basis weight by 2, the number of plies, to obtain the basis weight per sheet.

[0142] [Paper thickness (per 2-ply toilet paper) [μm]] Toilet paper was pulled out from the toilet roll, and the thickness of the two-ply toilet paper (two sheets in one set) was determined in accordance with the International Organization for Standardization standard ISO 12625-3.

[0143] (TS750 exterior and interior) Using the above-mentioned tissue softness measuring device TSA, the above-mentioned TS750 value measurement procedure was followed to obtain the TS750 outer surface, with the outer surface of the toilet paper (the surface that faces the outside of the toilet roll) as the measurement surface, and the TS750 inner surface, with the inner surface of the toilet paper (the surface that faces the inside of the toilet roll) as the measurement surface.

[0144] [Difference D (TS750 inner surface - TS750 outer surface)] The difference D between the TS750 inner surface and the TS750 outer surface (TS750 inner surface - TS750 outer surface) was calculated by subtracting the value of the TS750 outer surface from the value of the TS750 inner surface.

[0145] [Ratio R (TS750 inner surface / TS750 outer surface)] The ratio R of the TS750 inner surface to the TS750 outer surface (TS750 inner surface / TS750 outer surface) was calculated by dividing the value of the TS750 inner surface by the value of the TS750 outer surface.

[0146] <Evaluation> A sensory evaluation was performed for the following items, and the results were indicated by symbols (◎: excellent, ◯: good, △: acceptable, ×: unacceptable). The sensory evaluation was a relative evaluation of samples with the same toilet roll length.

[0147] [The texture of the outer surface of toilet paper] The smoother the outer surface of the toilet paper felt, the better the texture was rated (◎).

[0148] [Comeback] Referring to Fig. 8(a), the toilet roll was rotatably supported by a holder (not shown), and as shown in Fig. 8(c), of the two sheets constituting the two plies of toilet paper, the end of the outer sheet of the toilet roll was held with the fingers and unwound while facing upwards. When the end of the sheet reached the vertically upper part of the toilet roll, the state in which the inner sheet of the toilet roll was pulled out following the outer sheet was rated as excellent (◎), the state in which the inner sheet did not follow the outer sheet from the beginning and was not unwound was rated as poor (×), and the state in which the inner sheet separated from the outer sheet and fell off midway was rated as good (◯), fair (△), or poor (×) according to the degree of the state.

[0149] The test results are shown in Tables 1 to 3.

[0150] [Table 1]

[0151] [Table 2]

[0152] [Table 3]

[0153] As shown in Tables 1 to 3, in all of Examples 1 to 11 (all Examples) and Comparative Examples 1 to 5 (all Comparative Examples), the toilet roll had a roll length of 33 m or more and 100 m or less, and a roll diameter of 100 mm or more and 134 mm or less. The roll diameter was large enough to be freely rotatably stored in a typical toilet roll holder, and the roll length was long, allowing the roll to be transported and stored in a space-saving manner.

[0154] In addition, the basis weight per sheet constituting the two-ply toilet paper of Examples 1 to 11 is 11 g / m 2 More than 16g / m 2 This was a size that ensured adequate strength and water absorption.

[0155] In the examples 1 to 11, a bonding embossment (edge ​​embossment) is provided, and the outer surface of the TS750 is 12 dBV. 2 rms over 30dBV 2 rms or less and the TS750 inner surface was greater than the TS750 outer surface. The hand (smoothness) of the outer surface of the toilet paper was good or excellent and the toilet roll rewind was rated excellent or good.

[0156] In contrast, no joining embossment (edge ​​embossment) was provided in Comparative Examples 1 to 5. The toilet rolls of Comparative Examples 1 to 5 were evaluated as poor in terms of rewinding.

[0157] In addition, in Comparative Example 1, the outer surface of the TS750 is 31.5 dBV. 2 rms, which was above the upper limit of the range for the TS750 outer surface of the present invention, and the hand (smoothness) of the outer surface of the toilet paper was poor.

[0158] Comparative Example 3 has a basis weight of 16.9 g / m 2 This was above the upper limit of the basis weight range of the present invention. [Explanation of symbols]

[0159] 10,100 toilet rolls 11,12,110,120 sheets 11e First joining embossed portion 12e Second bonding embossed portion 13e Embossed section 11R, 12R Original roll 13,130 toilet paper 14,140 Paper tube 16,17 Embossing roll for bonding 20 Tissue Softness Measurement Device TSA 21 Sample stage 23 Sample 24 Sample fixing ring 25 blade rotor 25a blade 25b Motor 70 Raw material roll stand 71 Embossing roll unit 73 Guide Roller 74 Guide roller 76 Embossed section 77 Winding section DR Toilet roll diameter DC Core diameter P1 Peak TS7 value P2 TS750 peak

Claims

1. A toilet roll in which two sheets of toilet paper are overlapped and wound into a roll, The toilet roll has a winding length of 33 m or more and 100 m or less, a winding diameter of 100 mm or more and 134 mm or less, and a winding density of 0.790 m / cm 2 or more and 1.0011 m / cm 2 or less, The basis weight of each sheet is 11 g / m 2 16g / m or more 2 is as follows: Using a tissue softness measuring device (TSA), a toilet paper sample is placed on a sample stage with the outer side of the toilet roll facing up, and a bladed rotor is pressed from above with a pressing pressure of 100 mN, then rotated at a rotation speed of 2.0 per second. The TS750 outer surface, which is the intensity of the first maximum peak of the spectrum seen from the low frequency side when the vibration of the sample stage is measured with a vibration sensor, is 12 dBV. 2 rms or more 30dBV 2 is less than or equal to the rms The tissue softness measuring device TSA presses the bladed rotor from above onto the toilet paper sample, which is placed on the sample stage with the inner side of the toilet roll facing up, at a pressure of 100 mN, and then rotates the sample at a rotation speed of 2.0 per second. The TS750 inner surface, which is the intensity of the first maximum peak of the spectrum seen from the low frequency side when the vibration of the sample stage is measured with a vibration sensor, is greater than the TS750 outer surface. The toilet paper is a first bonding embossment for defining a bonding area where the two sheets are in close contact with each other; a second bonding embossed portion for defining a bonding area in cooperation with the first bonding embossed portion such that the two sheets are in close contact with each other, and for integrally bonding the two sheets together with the first bonding embossed portion; A toilet roll comprising:

2. The toilet roll according to claim 1, characterized in that the sheet contains wood pulp, and when the content of wood pulp in the sheet is W and the content of recycled paper pulp in the sheet is R, the content of recycled paper pulp in the sheet calculated by the formula R÷(W+R)×100 is 0% by mass or more and less than 40% by mass.

3. A toilet roll in which two sheets of toilet paper are overlapped and wound into a roll, The toilet roll has a winding length of 33 m or more and 100 m or less, a winding diameter of 100 mm or more and 134 mm or less, and a winding density of 0.790 m / cm 2 or more and 1.001 m / cm 2 or less, The basis weight of each sheet is 11 g / m 2 16g / m or more 2 is as follows: Using a tissue softness measuring device (TSA), a toilet paper sample is placed on a sample stage with the outer side of the toilet roll facing up, and a bladed rotor is pressed from above with a pressing pressure of 100 mN, then rotated at a rotation speed of 2.0 per second. The TS750 outer surface, which is the intensity of the first maximum peak of the spectrum seen from the low frequency side when the vibration of the sample stage is measured with a vibration sensor, is 12 dBV. 2 rms or more 30dBV 2 is less than or equal to the rms The tissue softness measuring device TSA presses the bladed rotor from above onto the toilet paper sample, which is placed on the sample stage with the inner side of the toilet roll facing up, at a pressure of 100 mN, and then rotates the sample at a rotation speed of 2.0 per second. The TS750 inner surface, which is the intensity of the first maximum peak of the spectrum seen from the low frequency side when the vibration of the sample stage is measured with a vibration sensor, is greater than the TS750 outer surface. The toilet paper is a first bonding embossment for defining a bonding area where the two sheets are in close contact with each other; a second bonding embossed portion for defining a bonding area in cooperation with the first bonding embossed portion such that the two sheets are in close contact with each other, and for integrally bonding the two sheets together with the first bonding embossed portion; A method for producing toilet paper comprising: The method includes a forming step of forming the two-ply toilet paper by overlapping the two sheets, and a winding step of winding the formed two-ply toilet paper into a roll by a predetermined length, with a predetermined winding diameter and a predetermined winding density, The forming step is performed so that the outer surface of the TS750 is 12 dBV 2 rms or more 30dBV 2 rms or less, and the TS750 inner surface is larger than the TS750 outer surface. (1) a no-embossing process in which sheets of different paper qualities are used as the two sheets, and the two sheets are superimposed on each other without embossing the entire surface of each of the two sheets; (2) a double embossing process in which the two sheets are made of the same or different paper materials, and the two sheets are embossed under different embossing conditions on the entire surface thereof before the two sheets are superimposed; (3) a single embossing process in which the two sheets are made of the same or different paper materials, and the two sheets are superimposed on each other and embossed all over the surfaces of the two sheets at the same time; A first step selected from the following: a second step of performing a bonding embossing process after the first step, which forms a first bonding embossed portion for defining a bonding area where the two sheets are in close contact with each other, and a second bonding embossed portion for defining a bonding area where the two sheets are in close contact with each other together with the first bonding embossed portion and integrally bonding the two sheets together with the first bonding embossed portion; A method for producing a toilet roll, comprising:

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