Toilet roll and method for manufacturing the same

Abstract

To provide a toilet roll in which a positional deviation in perforations and ply peeling are prevented, and to provide a manufacturing method thereof.SOLUTION: There is provided a 2-ply toilet roll whose wound length is 40-100 m, wound diameter is 100-134 mm, basis weight per sheet is 11-20.5 g / m2, and roll density is 1.02-1.48 m / cm2. The toilet paper is given a single embossment on an entire region of a paper space, and an embossment for bonding for ply peeling prevention, and is wound so that an embossment recess is outside the roll. Breaking perforations that cross the toilet paper in the width direction are formed at constant intervals along the longitudinal direction of the toilet paper. The depth of the single embossment is 115-143 μm.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a toilet roll in which a two-ply toilet paper with two sheets overlapped is wound in a roll shape and a method for manufacturing the same.

Background Art

[0002] In a toilet roll in which a two-ply toilet paper with two sheets overlapped is wound in a roll shape, space saving during carrying and storage of the toilet roll product is achieved by increasing the winding length per roll.

[0003] In order to increase the winding length while maintaining the roll diameter within a predetermined dimension, it is effective to reduce the basis weight of the sheet. However, in that case, generally, the strength decreases, and the bulkiness and the feeling of use also decrease. Patent Document 1 proposes a toilet roll in which the surface of the sheet is made into an uneven shape to improve the softness of the sheet, and by paying attention to the winding density of the roll, etc., the winding length per roll is increased without reducing the basis weight, and the softness of the sheet and the roll is ensured.

[0004] Cited Document 1 discloses that as the uneven shape of the surface of the sheet, an emboss with a depth of 0.05 mm to 0.40 mm is preferable, and as the type of emboss, in the case of a double emboss in which each sheet of the two-ply is embossed and then overlapped, the paper thickness becomes too high and the winding density becomes low, and the winding length may not be ensured. Therefore, in particular, a single emboss in which an embossed convex portion is pressed only from one surface of the two-ply toilet paper to form an emboss is preferable.

[0005] By the way, in soft toilet paper, generally, in order to facilitate the separation of the toilet paper from the toilet roll, perforations extending in the width direction of the toilet paper are formed at regular intervals in the longitudinal direction of the toilet paper.

Prior Art Documents

Patent Document

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] When a perforation for breaking is provided in a two - ply toilet paper with a single emboss as described above, if the winding is tightened so that the roll diameter is within a predetermined range while increasing the roll length, a longitudinal shift is likely to occur between the two sheets constituting the two - ply toilet paper. This shift becomes larger as the roll length increases. Also, this shift becomes larger when the paper quality of the sheet is smooth. As a result of the shift, ply separation between the two - ply toilet paper occurs, making it difficult to integrally pull out the two - ply toilet paper from the toilet roll, or positional deviation of the perforations of the two sheets constituting the two - ply occurs, making it impossible to cleanly cut the toilet paper at the perforations.

[0008] An object of the present invention is to provide a two - ply toilet roll in which the roll diameter is within a predetermined dimension, the roll length per roll is long, the softness of the toilet paper is ensured, and displacement of the perforation position and ply peeling are prevented.

Means for Solving the Problems

[0009] As a result of intensive studies to solve the above problems, the inventor found that a two - ply toilet roll in which two sheets are overlapped and wound in a roll shape, the roll length of the toilet roll is 40 m or more and 100 m or less, the roll diameter of the toilet roll is 100 mm or more and 134 mm or less, the basis weight per sheet is 11 g / m 2 or more and 20.5 g / m 2 or less, and the winding density of the toilet roll is 1.02 m / cm2 Above 1.48 m / cm 2 Below, the toilet paper is provided with a single emboss for the entire paper surface and a joining emboss for preventing ply separation of two sheets, and is wound so that the emboss recess is on the outer side of the roll. The toilet paper has perforation seams that cross the toilet paper in the width direction formed at regular intervals along the longitudinal direction of the toilet paper. The single emboss Of the The emboss depth is 115 μm or more 127 μm or less, and The embossing depth of the emboss for joining is 124 μm or more and 143 μm or less. It has been found that the above problems can be solved by a toilet roll.

[0010] Specifically, the present invention has the following configuration.

[0011] [1] A toilet roll in which a two-ply toilet paper with two sheets overlapped is wound in a roll shape, The winding length of the toilet roll is 40 m or more and 100 m or less, The winding diameter of the toilet roll is 100 mm or more and 134 mm or less, The basis weight per sheet is 11 g / m 2 or more and 20.5 g / m 2 or less, and The winding density of the toilet roll is 1.02 m / cm 2 or more and 1.48 m / cm 2 or less, and The toilet paper is provided with a single emboss for the entire paper surface and a joining emboss for preventing ply separation of two sheets, and is wound so that the emboss recess is on the outer side of the roll, The toilet paper has perforation seams that cross the toilet paper in the width direction formed at regular intervals along the longitudinal direction of the toilet paper, The single emboss Of the The emboss depth is 115 μm or more 127 μm μm or less, The embossing depth of the emboss for joining is 124 μm or more and 143 μm or less. A toilet roll characterized by the above.

[0012] [2] The roll length of the toilet roll is 40 m or more and 60 m or less, and the basis weight per sheet is 13.0 g / m 2 or more and 20.5 g / m 2 or less. The toilet roll according to [1], characterized in that.

[0013] [3] The roll length of the toilet roll is 60 m or more and 80 m or less, and the basis weight per sheet is 12.0 g / m 2 or more and 18.5 g / m 2 or less. The toilet roll according to [1], characterized in that.

[0014] [4] The roll length of the toilet roll is 80 m or more and 100 m or less, and the basis weight per sheet is 11.0 g / m 2 or more and 17.0 g / m 2 or less. The toilet roll according to [1], characterized in that.

[0015] [5] The embossing pattern of the single emboss is an aggregate of dots set to occupy a predetermined area, and is arranged such that the array direction forms an inclination angle with respect to the width direction and the longitudinal direction of the toilet paper. The toilet roll according to any one of [1] to [4], characterized in that.

[0016] [6] A method for manufacturing a toilet roll, a step of performing a single emboss on a laminated sheet in which two sheets are overlapped, a step of performing a joining emboss on the laminated sheet subjected to the single emboss, a step of forming a perforation for breaking on the laminated sheet subjected to the joining emboss, a step of winding the laminated sheet on which the perforation for breaking is formed into a roll shape so that the emboss recess of the single emboss faces the outside of the roll, including In the process of applying a single emboss, the embossing roll is brought into pressure contact with the surface on the outer side of the roll of the laminated sheet, and an embossing recess having an embossing depth of 115 μm or more 127 μm or less is formed on the surface, In the process of applying a joining emboss, the joining emboss is formed such that the embossing depth of the joining emboss is 124 μm or more and 143 μm or less. A method for manufacturing a toilet roll, characterized in that

[0017] [7] The embossing roll has an embossing pattern that is an aggregate of dots set to occupy a predetermined area, and the embossing pattern is provided such that its arrangement direction forms an inclination angle with respect to the width direction and the longitudinal direction of the laminated sheet. The method for manufacturing a toilet roll according to [6].

[0018] [8] The toilet roll is the toilet roll according to any one of [1] to [5]. The method for manufacturing a toilet roll according to [6] or [7], characterized in that [Effect of the Invention]

[0019] According to the present invention, it is possible to provide a two-ply toilet roll in which the roll diameter is within a predetermined dimension, the winding length per roll is long, the softness of the toilet paper is ensured, and misalignment of the perforations and ply peeling are prevented. Therefore, according to the present invention, since the roll diameter of the toilet roll is within a predetermined dimension and the winding length per roll is long, space saving during carrying and storage can be achieved. Since the softness of the toilet paper is ensured, it has an excellent feeling of use. Since misalignment of the perforations and ply peeling are prevented, it is possible to provide a toilet roll that does not cause inconvenience during use. According to the present invention, in particular, regardless of the paper quality, for example, even when the smoothness of the sheet is high, it is possible to provide a toilet roll in which misalignment of the perforations and ply peeling are prevented. [Brief Description of the Drawings]

[0020]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Mode for Carrying Out the Invention

[0021] Hereinafter, a toilet roll and a manufacturing method thereof according to an embodiment of the present invention will be described with reference to the drawings. The following embodiments and drawings are described for illustrative purposes and do not limit the present invention.

[0022] (First Embodiment) (Toilet Roll) FIG. 1 is a schematic diagram for explaining the structure of a toilet roll according to an embodiment of the present invention. Referring to FIG. 1, a toilet roll 10 according to an embodiment of the present invention is formed by winding a so-called two-ply toilet paper 13, in which two sheets 11 and 12 are overlapped, around a paper tube 14, which is a cylindrical core, in a roll shape by a predetermined length.

[0023] (Sheet) Each of the two sheets 11 and 12 that are components of the toilet paper 13 is obtained by papermaking a slurry containing a pulp component that is a fiber raw material.

[0024] (Pulp Component) Examples of the pulp component include wood pulp, non-wood pulp, and waste paper pulp. Examples of wood pulp produced from wood as 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), oxygen bleached kraft pulp (OKP), etc. Further, semi-chemical pulps such as semi-chemical pulp (SCP), chemigroundwood pulp (CGP), etc., and mechanical pulps such as groundwood pulp (GP), thermomechanical pulp (TMP, BCTMP), etc. may be mentioned, but are not particularly limited. Examples of non-wood pulp produced from plants and animals other than wood as raw material include cotton-based pulps such as cotton linter and cotton lint, non-wood-based pulps such as hemp, wheat straw, bagasse, etc., cellulose, chitin, chitosan, etc. isolated from jellyfish, seaweed, etc., but are not particularly limited. Examples of wastepaper pulp produced from wastepaper (pulp for papermaking) as raw material include so-called milk carton pulp using a paper pack for filling and packaging liquids such as milk cartons as raw material, and deinked pulp using newspapers, magazines, etc. as raw material, but are not particularly limited.

[0025] As the pulp component, one of the above may be used alone, or two or more may be mixed and used. Since these pulp components greatly affect the quality of toilet paper, they are appropriately blended in a predetermined type and blending ratio according to the required quality.

[0026] For example, as the pulp component, at least one selected from softwood pulp and hardwood pulp can be preferably used. Softwood pulp has long fibers and high strength, and can impart strength to the sheet to be formed. Further, hardwood pulp has short fibers and is flexible, and can provide uniformity, good texture, softness, etc. to the sheet to be formed. In an embodiment of the present invention, it is preferable to use softwood pulp and hardwood pulp in combination, and it is more preferable to use softwood kraft pulp (NKP) and hardwood kraft pulp (LKP) in combination.

[0027] When using softwood pulp and hardwood pulp in combination, the L / N ratio indicating the blending ratio (mass ratio) of softwood pulp and hardwood pulp is preferably, for example, 10 / 90 to 90 / 10, more preferably 20 / 80 or more, even more preferably 30 / 70 or more, and also more preferably 80 / 20 or less, even more preferably 70 / 30 or less.

[0028] (Optional component) For the sheet, various chemicals may be added as optional components for the required quality and stable operation. Examples of optional components include dry paper strengthening agents, wet paper strengthening agents, softeners, bulking agents, dyes, fragrances, dispersants, drainage improvers, pitch control agents, yield improvers, sizing agents, etc. Examples of dry paper strengthening agents include cationized starch, polyacrylamide (PAM), carboxymethyl cellulose (CMC), etc. Examples of wet paper strengthening agents include polyamide epichlorohydrin, urea, melamine, thermally crosslinkable polyacrylamide, etc. Examples of softeners include anionic surfactants, nonionic surfactants, cationic surfactants, and zwitterionic surfactants, etc. The above optional components may be used alone or in combination of two or more.

[0029] In the embodiments of the present invention, the types (paper quality such as material and physical properties) of the two sheets 11 and 12 that are overlapped with each other may be the same or different depending on the required quality, etc.

[0030] (Roll length of toilet roll) In the embodiments of the present invention, the roll length of the toilet roll, which is the length of the toilet paper 13 wound around the paper tube 14, is 40 m or more and 100 m or less. The roll length can be determined, for example, by actually measuring the length while unwinding the toilet paper 13 from the toilet roll 10. The conventional mainstream toilet paper roll length is around 30 m. On the other hand, when the toilet roll length is in the range of 40 m or more and 100 m or less, the length of the toilet paper 13 per roll is long, and the effects of space saving during carrying and storage of the toilet roll can be obtained. When the toilet roll length exceeds 100 m, generally, the roll diameter of the toilet roll becomes large, and the toilet roll 10 becomes difficult to fit in a general toilet roll holder. When the toilet roll length is less than 40 m, the effect of space saving during carrying and storage is small.

[0031] (Toilet roll diameter) In an embodiment of the present invention, the roll diameter DR of the toilet roll, which is the roll diameter of the toilet paper 13 wound in a roll shape, is 100 mm or more and 134 mm or less. The roll diameter DR can be measured using, for example, a caliper. When the roll diameter DR of the toilet roll is in the range of 100 mm or more and 134 mm or less, the toilet roll 10 can fit in a general toilet roll holder and be rotatably supported therein. When the roll diameter DR of the toilet roll becomes larger than 134 mm, the toilet roll 10 becomes difficult to fit in a general toilet roll holder. Further, when the roll diameter DR of the toilet roll is smaller than 100 mm, the roll length of the toilet roll is limited, and it becomes difficult to save space during carrying and storage by increasing the roll length. Also, when trying to ensure a long roll length of the toilet roll with a small roll diameter DR, the paper thickness, bulkiness of the toilet paper 13, and basis weight of the constituent sheets 11, 12, etc. are limited, making it difficult to ensure a good feeling of use and strength.

[0032] (Toilet roll winding density) In an embodiment of the present invention, the winding density of the toilet roll is 0.65 m / cm 2 or more and 2.05 m / cm 2 or less. The winding density of the toilet roll is calculated by the following formula (I). (Winding density) = (roll length × ply number) ÷ (cross-sectional area of the toilet roll) (Formula I)

[0033] The cross-sectional area of the toilet roll corresponds to the area of the portion constituted by the toilet paper 13 on the side surface of the toilet roll 10 shown in Fig. 1(b). That is, the cross-sectional area of the toilet roll is the area obtained by subtracting the area of a circle with the core diameter DC, which is the outer diameter of the paper tube 14, as the diameter from the area of a circle with the winding diameter DR as the diameter. The cross-sectional area of the toilet roll is calculated by the following formula (II). (Cross-sectional area) = (Winding diameter DR of toilet roll ÷ 2) 2 × 3.14 - (Core diameter DC ÷ 2) 2 × 3.14 (Formula II)

[0034] For example, when the winding length of the toilet roll 10 is 50 m, the winding diameter DR is 118 mm, and the core diameter DC of the paper tube 14 is 38 mm, since the toilet paper 13 is 2-ply, the winding density is (50 m × 2) ÷ { (118 mm ÷ 2) 2 × 3.14 - (38 mm ÷ 2) 2 × 3.14}, and calculating this gives 1.02 m / cm 2 and it becomes like this.

[0035] When the winding density of the toilet roll is 0.65 m / cm 2 or more and 2.05 m / cm 2 or less, it is possible to obtain a toilet roll that satisfies the above-mentioned winding diameter and winding length and ensures the softness of the toilet paper. When the winding density of the toilet roll is greater than 2.05 m / cm 2 , the sheets are wound tightly, making it difficult to ensure the softness of the toilet paper. When the winding density of the toilet roll is less than 0.65 m / cm 2 , the paper thickness, bulkiness, etc. are low, and good usability and strength may not be obtained, or the winding length may be short.

[0036] (Toilet paper) The toilet paper 13 is a so-called 2-ply toilet paper and has a form of a laminated sheet in which two sheets 11, 12 are overlapped.

[0037] (Grammage per sheet) In an embodiment of the present invention, the grammage per sheet of the two sheets 11 and 12 constituting the toilet paper 13 is 11.0 g / m 2 or more and 20.5 g / m 2 or less. The grammage per sheet can be obtained by measuring the grammage of the two-ply toilet paper 13 in accordance with the provisions of Japanese Industrial Standard JIS P8124 and dividing the measured grammage by 2, which is the number of plies. That is, the two-ply toilet paper 13 is conditioned in accordance with 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, a size of 10 cm × 10 cm, with the two sheets 11 and 12 stacked. Then, the weight of the cut two-ply toilet paper 13 is measured, and the measured weight is divided by 0.01 m 2 of the cut surface area of the two-ply toilet paper 13 to measure the grammage of the two-ply toilet paper 13. Then, the grammage per sheet can be obtained by dividing the measured grammage by 2, which is the number of plies.

[0038] If the grammage per sheet is less than 11.0 g / m 2 , the strength is low, and the bulkiness and usability are inferior. On the other hand, if the grammage per sheet exceeds 20.5 g / m 2 , generally, the paper thickness increases, and the roll diameter of the toilet roll becomes large. At this time, if it is desired to keep the roll diameter DR of the toilet roll within the range of the roll diameter according to the above-described embodiment of the present invention, it becomes difficult to secure the roll length of the toilet roll. Also, if it is desired to obtain the roll length within the range according to the above-described embodiment of the present invention, it is necessary to reduce the paper thickness, and the bulkiness is reduced and it becomes hard, etc., and the texture of the toilet paper is impaired.

[0039] (Embossing) Referring to FIG. 1(a), in an embodiment of the present invention, an embossed portion 13a and a joining embossed portion 13b are provided on the paper surface of the toilet paper 13. The embossed portion 13a and the joining embossed portion 13b can be formed by embossing.

[0040] (Embossed portion) Specifically, on the toilet paper 13, a large number of embossed portions 13a are continuously formed by repeating the embossing pattern P, where one surface side is an embossed concave portion and the other surface side is an embossed convex portion across the entire paper area. Here, in this specification, the term "entire paper area" does not refer to exactly 100% of the paper area, but should be interpreted as being approximately 100% of the paper area, preferably 90% or more of the paper area.

[0041] In the example shown in FIG. 1(1), the embossing pattern P is a set of dots forming a point-symmetric shape in which the embossed portions 13a are arranged concentrically, and is set to occupy a substantially square area with one side surrounded by a two-dot chain line being approximately 28.5 mm. Note that the configuration of the embossing pattern P applicable to the embodiment of the present invention is not limited to the example shown in FIG. 1(1).

[0042] The toilet paper 13 is wound around the toilet roll 10 such that the embossed concave portion is on the outer side of the roll and the embossed convex portion is on the inner side of the roll. By providing the embossed concave portion on the outer surface of the toilet paper 13 in this way, the tactile sensation of the outer surface of the toilet paper 13 can be improved, and moreover, the softness of the sheet can be enhanced.

[0043] (Embossing) Embossing refers to a process of forming an embossed convex portion on one surface of both surfaces of a sheet to be embossed and an embossed concave portion formed on the back side of the embossed convex portion 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 having substantially complementary shapes mesh with each other, or by a so-called "unmatched" embossing roll in which the shapes of the male (convex) embossing roll and the female (concave) embossing roll are not the same and a shearing force is applied to the sheet when the two mesh with each other, or by a male (convex) embossing steel roll and a plane rubber roll.

[0044] (Single embossing) Generally, for embossing two-ply toilet paper, there are a so-called double embossing method in which each of the two sheets that are components of the toilet paper is embossed and then they are overlapped, and a so-called single embossing method in which the two sheets are overlapped and then the entire laminate is embossed. The embossing applied to the embodiments of the present invention is a single embossing in which the sheets 11 and 12 that are components of the two-ply toilet paper 13 are overlapped with each other and then embossed.

[0045] In the case of double embossing, since two sheets with increased paper thickness due to embossing are overlapped, the paper thickness of the entire toilet paper increases. Therefore, when trying to wind the toilet paper into a toilet roll with a predetermined roll diameter, it may be difficult to increase the winding length. Also, if the embossing depth is made shallow to reduce the paper thickness, there may be a case where sufficient softness cannot be provided to the sheet. On the other hand, in the case of single embossing, since the embossing is applied after the two sheets are overlapped, the paper thickness of the entire toilet paper can be relatively kept low. Therefore, in the embodiments of the present invention, by adopting single embossing, it is possible to impart softness to the sheet without increasing the paper thickness.

[0046] (Embossing depth) Referring to FIG. 2(a), in the embodiments of the present invention, the embossing depth D, which is the depth of the embossing recess of the embossed portion 13a of the toilet paper 13, is preferably 0.8 mm or less, more preferably 0.05 mm or more and 0.6 mm or less, and still more preferably 0.1 mm or more and 0.4 mm or less.

[0047] As the embossing depth D increases, the unevenness of the embossing becomes more prominent. Due to the unevenness of the embossing, the bulk of the toilet paper 13 increases, and the paper thickness T of the entire toilet paper increases. Although it also depends on the winding length of the roll, if the size of the embossing depth D exceeds the above range, the paper thickness T becomes too high, and the winding diameter DR of the toilet roll 10 exceeds the above predetermined range, making it difficult to rotatably hold the toilet roll 10 with respect to the toilet holder in some cases. Also, if the embossing depth D is small and the unevenness of the embossing is insufficient, sufficient softness may not be imparted to the toilet paper 13 in some cases.

[0048] (Method for measuring embossing depth) The method for measuring the embossing depth D will be described. The embossing depth D can be obtained by measuring the height difference of the embossing using a shape measurement laser microscope. The shape measurement laser microscope scans a laser light source, which is a point light source, through an objective lens to a plurality of pixels that divide the X-Y plane within the observation field of view, and detects the reflected light for each pixel with a light receiving element. Then, the objective lens is driven in the height (Z-axis) direction, and the height information and the reflected light amount are detected with the Z-axis position having the highest reflected light amount as the focus. By repeating the scan in this way, an overall in-focus light amount super-depth image and a height image (information) are obtained. Since the laser light source is a pinhole confocal optical system, the measurement accuracy is high.

[0049] As the shape measurement laser microscope, for example, the product name "One Shot 3D Measurement Macroscope VR-3100" manufactured by KEYENCE Corporation can be used. As the image observation, measurement, and image analysis software for the laser microscope, for example, the product name "VR-H1A" can be used. In this embodiment, the measurement is performed under the conditions of a measurement magnification of 12 times and a field of view area of 24 mm × 18 mm. Note that the measurement magnification and the field of view area may be appropriately changed depending on the size of the embossing to be obtained.

[0050] As shown in Fig. 2(b), the measurement of the embossing depth is performed on the surface on the sheet 11 side of the toilet paper 13 provided with the embossing recesses (the surface on the outer side of the roll of the toilet roll 10). First, the longest part a where the straight-line distance between two opposing points at the periphery of the recess of the embossing part 13a is the longest is determined.

[0051] Fig. 3(a) shows the height profile on the X-Y plane by a shape measurement laser microscope, and the height of the surface of the toilet paper 13 is represented by shading. The dark-colored parts in Fig. 3(a) indicate the individual embossing parts 13a. From Fig. 3(a), the longest part a of one embossing part 13a can be distinguished. When a line segment A-B is drawn across this longest part a, a height (measurement cross-sectional curve) profile of the embossing part 13a as shown in Fig. 3(b) can be obtained. At this time, since the convex (non-embossing part) and concave parts of the embossing on the surface on the sheet 11 side of the toilet paper 13 can be seen from the shading of the color in the X-Y plane image, the line segment A-B may be determined so as to cross the part where the convex and concave parts are adjacent.

[0052] The height profile in Fig. 3(b) is a (measurement) cross-sectional curve S representing the unevenness of the actual surface of the sample of the toilet paper 13 (the surface on the sheet 11 side), and includes noise (sharp peaks caused by fiber lumps on the surface of the toilet paper, fibers growing in a whisker shape, or parts without fibers). Therefore, when calculating the height difference of the unevenness, it is necessary to remove such noise peaks.

[0053] Therefore, as shown in Fig. 3(c), a "contour curve" W is calculated from the cross-sectional curve S of the height profile, two inflection points P1 and P2 that are convex upward are obtained from among this contour curve W, then the minimum value sandwiched between the inflection points P1 and P2 is obtained, and this minimum value is taken as the minimum value Min of the depth. Furthermore, the average value of the depth values of the inflection points P1 and P2 is taken as the maximum value Max of the depth. In this way, the embossing depth D is obtained by the following formula (III). Embossing depth D = maximum value Max - minimum value Min (Formula III) Also, the distance (length) in the X-Y plane between the inflection points P1 and P2 is defined as the length of the longest part a.

[0054] The "contour curve" shown in Fig. 3(c) is obtained by removing the surface roughness components with wavelengths shorter than the wavelength λc: 800 μm (where λc is the "filter that defines the boundary between the roughness component and the waviness component" described in JIS-B0601 "3.1.1.2") from the cross-sectional curve shown in Fig. 3(b) using a low-pass filter. Note that if λc is set to be less than or equal to the interval between P1 of adjacent embossed portions 13a (hereinafter also referred to as the embossing pitch), there is a possibility that the peak will be recognized as noise. Therefore, λc is set to be less than the embossing pitch. For example, when the embossing pitch is 800 μm or less, for example, λc is set to 250 μm. The interval between P1 of adjacent embossed portions 13a is the interval between two P1s when P1, P2, and P1 of adjacent embosses are arranged in this order for the next embossed portion 13a connected to the left or right in Fig. 3(c), and P1 and P2 are obtained in the same manner.

[0055] Similarly, referring to Fig. 2(b), for the longest part b where the straight-line distance between two opposing points at the periphery of the embossed concave portion of the embossed portion 13a in the direction perpendicular to the longest part a is the longest, the embossing depth D is also measured. Among the embossing depths D of the longest part a and the longest part b, the larger value is adopted as the embossing depth D of one of the embossed portions 13a. The above measurements are performed for any 10 embossed portions 13a on the surface side of the sheet 11 of the toilet paper 13, and the average value is adopted as the final embossing depth D.

[0056] When measuring the emboss depth D, it is measured at a portion corresponding to 10% of the roll length of the toilet roll 10 from the end of the toilet paper 13 on the outer roll side of the toilet roll 10 (the position where the use of the toilet paper 13 starts in the toilet roll 10). For example, when the roll length is 50 m, the emboss depth D is measured at a portion 5 m from the end, which is 10% of 50 m, from the end. In addition, when the portion corresponding to 10% of the roll length hits the perforation 15, it is measured at a portion on the outer roll side of the perforation 15. This is because the emboss depth D varies depending on the degree of emboss crushing at the start and end of the winding of the toilet paper 13 in the toilet roll 10. Thereby, the influence of the measurement position as a factor of variation in the measurement value can be reduced.

[0057] (Emboss for joining) Referring to (1) of FIG. 1, in an embodiment of the present invention, the toilet paper 13 is provided with a joining emboss portion 13b for joining the constituent sheets 11 and 12 to each other. The joining emboss portion 13b is provided only in a partial region of the paper surface in order to suppress the ply separation of the sheets 11 and 12 constituting each layer of the toilet paper 13, and defines a joining region for integrally joining the sheet 11 and the sheet 12.

[0058] The joining emboss portion 13b may be formed, for example, as shown in (a) of FIG. 1, so as to extend along the longitudinal direction (MD direction) at both side edges in the width direction (CD direction) of the toilet paper 13. The pattern of the joining emboss portion 13b formed in this way is also particularly referred to as an edge emboss.

[0059] The edge emboss is provided so as not to cover the central portion in the width direction of the toilet paper. Thereby, it is possible to prevent the edge emboss from degrading the texture of the central portion of the paper surface of the toilet paper. The edge emboss may be provided, for example, in a range of 10 to 50 mm from each edge in the width direction of the toilet paper.

[0060] In the edge emboss, a group of a large number of joining emboss portions 13b may be continuously provided in the longitudinal direction. Also, in the edge emboss, a group of a large number of joining emboss portions 13b may be intermittently provided in the longitudinal direction.

[0061] The joining emboss portion 13b is preferably formed so as not to protrude outward in the thickness direction from both the front and back surfaces of the toilet paper 13. By doing so, on both the front and back surfaces of the toilet paper, the surface of the joining emboss portion 13b is at the same level as the surface of the toilet paper or a recess having a height (depth) less than that, so that the smooth touch feeling of the surface of the toilet paper is not deteriorated.

[0062] (Emboss depth of the joining emboss portion) The emboss depth of the joining emboss portion 13b can be measured by the same method as the method for measuring the emboss depth of the emboss portion 13a described above. In an embodiment of the present invention, the joining emboss depth, which is the depth of the emboss recess of the joining emboss portion 13b of the toilet paper 13, is preferably 0.8 mm or less, more preferably 0.05 mm or more and 0.6 mm or less, and still more preferably 0.1 mm or more and 0.4 mm or less.

[0063] (Perforation for tearing) Referring to FIG. 1(a), in an embodiment of the present invention, in the toilet paper 13, in order to facilitate the separation of the toilet paper 13 pulled out from the toilet roll 10 from the toilet roll, perforations 15 extending in the width direction of the toilet paper are formed at regular intervals in the longitudinal direction of the toilet paper 13. This regular interval in the longitudinal direction is, for example, 100 to 300 mm, but is not limited thereto and can be arbitrarily set in consideration of the amount of paper required and ease of use when using the toilet.

[0064] The perforations 15 for breaking are determined in terms of the number, dimensions, distribution in the width direction, etc. of the perforations so that the toilet paper 13 does not break when not intended, and so that the toilet paper breaks easily when a shearing force is applied to the toilet paper 13. From the viewpoint of ease of breaking, the perforations 15 for breaking preferably extend through the thickness direction of the toilet paper 13 and straddle both side edges in the width direction of the toilet paper 13. The perforations for breaking can be provided by any known perforating device.

[0065] (Examples of a method and manufacturing equipment for manufacturing a toilet roll according to an embodiment of the present invention) With reference to FIG. 4, an example of a method and equipment applicable for manufacturing a toilet roll according to an embodiment of the present invention will be described. The toilet roll 10 can be manufactured, for example, as follows.

[0066] (Manufacture of a parent roll) Parent rolls 11R and 12R for manufacturing the toilet paper 13 having the sheets 11 and 12 as constituent elements are manufactured. Specifically, using a paper-making machine (not shown), wide (with a width several times to about twenty-some times the width of the toilet roll) and long sheets 11L and 12L are paper-made from a papermaking slurry (paper stock) while being wound up, and the parent rolls 11R and 12R around which the sheets 11L and 12L are wound are manufactured. As the paper-making machine, for example, known paper-making machines such as a twin-wire former method, a cylinder former method, a suction press former method, and a crescent former method can be used.

[0067] The paper-making machine may be provided with a creping section for performing creping. In the creping section, during the drying of the sheet (web) being paper-made in the parent roll manufacturing process, if necessary, very fine wavy wrinkles called crepe can be imparted to the sheet by a creping doctor. The crepe can impart softness, bulkiness (bulk feeling), absorbency, aesthetic appearance (the shape of the crepe), a good touch feeling, etc. to the sheet.

[0068] Further, the paper-making machine may be provided with a calendar section. In the calendar section, the dried sheet can be subjected to a calendar process of sandwiching and pressing the sheet from above and below by a pair of calendar rolls as necessary. As a result, the sheets 11L and 12L are compressed, and the paper thickness is adjusted and made uniform, and the surface is smoothed. The calendar section may be provided separately from the paper-making machine, and the calendar process may be performed in any manufacturing process after the parent roll manufacturing process. The calendar process may be performed in multiple stages.

[0069] (Manufacture of toilet roll) Using the parent rolls 11R and 12R, a toilet roll is manufactured. FIG. 4 is a schematic diagram showing an example of manufacturing equipment applicable to the manufacture of a toilet roll according to an embodiment of the present invention. The methods shown below and the manufacturing equipment shown in FIG. 4 are for illustrative purposes and do not limit the present invention. The parent rolls 11R and 12R are rotatably attached to the parent roll stand 20 and feed out the sheets 11L and 12L while being rotationally driven by a base paper sheet feeding device (not shown). The sheets 11L and 12L fed out from the parent rolls 11R and 12R are wound around the polymerization roll 30, overlapped with each other, and conveyed to the embossing section 21 arranged on the downstream side of the parent roll stand 20. Further downstream of this embossing section 21, a perforation forming section 22 and a winding section 23 are arranged in sequence.

[0070] The embossing section 21 is, in short, a unit that embosses the sheets 11L and 12L. The embossing section 21 includes an embossing roll unit 21A and a joining embossing roll unit 21B. In the embossing roll unit 21A, a single emboss extending over the entire paper surface of the toilet paper 13L is applied, and in the joining embossing roll unit 21B, edge embosses are applied to both side edges in the width direction of the toilet paper 13L.

[0071] The embossing roll unit 21A includes an embossing roll 24 and a backup roll 25 that is movably arranged along the direction facing the embossing roll, and the laminated sheets 11L and 12L are inserted therebetween.

[0072] The embossing roll 24 is rotatable, and concavo-convex portions corresponding to the embossing pattern P of the embossing portion 13a shown in FIG. 1 are formed on the outer peripheral surface of the embossing roll 24. In this example, at least the concavo-convex portions of the embossing roll 24 are formed of metal, while the surface portion of the backup roll 25 is formed of a hard rubber-like elastic body such as a hard synthetic rubber that can be elastically deformed.

[0073] As a result of the backup roll 25 being pressed against the outer peripheral surface of the embossing roll 24 with a predetermined pressure, a common embossing process (single embossing) is performed on the sheets 11L and 12L passing between them. At this time, by varying the predetermined pressure when the backup roll 25 is pressed against the outer peripheral surface of the embossing roll 24, the embossing depth of the formed single embossing can be controlled.

[0074] Next, a joining embossing roll unit 21B having a joining embossing wheel 26 and a receiving roll 27 facing each other is arranged on the downstream side of the embossing roll unit 21A in the embossing portion 21, and a joining embossing portion for preventing peeling is formed by inserting and pressing a laminate (toilet paper 13L) of the sheet 11L and the sheet 12L therebetween.

[0075] In the embossing portion 21, the wide toilet paper 13L formed by the sheets 11L and 12L laminated on each other is sent to the perforation forming portion 22 arranged downstream thereof.

[0076] The perforation forming section 22 forms perforations that cross the toilet paper 13L in the width direction 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 perforations.

[0077] In this example, the perforation processing device is a rotating blade holder 28h that is driven to rotate, and a comb-shaped cutter 28c with a discontinuous cutting edge that forms a straight line along a direction parallel to the rotation axis of the rotating blade holder is attached to the rotating blade holder 28h, and a fixed blade holder 29h that is held in a fixed state facing the rotating blade holder 28h, and a straight cutter 29c with a cutting edge that is continuous in a straight line along a direction parallel to the rotation axis of the rotating blade holder 28h is attached to the fixed blade holder 29h.

[0078] The perforation processing device passes the long toilet paper 13L between the comb-shaped cutter 28c of the rotating blade holder 28h and the straight cutter 29c of the fixed blade holder 29h. As a result, perforations corresponding to the cutting edges of the comb-shaped cutter 28c are formed across both side edges in the width direction of the toilet paper 13L.

[0079] More specifically, the toilet paper 13L passes across the cutting edge of the straight cutter 29c attached to the fixed blade holder 29h, and the comb-shaped cutter 28c of the rotating blade holder 28h rotates at a peripheral speed corresponding to the passing speed of the toilet paper 13L. Perforations are formed in the toilet paper 13L when the comb-shaped cutter 28c passes through the straight cutter 29c. The perforations formed by the comb-shaped cutter 28c and the straight cutter 29c extend across both side edges in the width direction of the toilet paper 13L and serve as perforations for separating the toilet paper 13L along its width direction.

[0080] In the perforation forming section 22, the wide toilet paper 13L with perforations for tearing is sent to the winding section 23 arranged on the downstream side thereof. In the winding section 23, the leading end of the toilet paper 13L sent from the perforation forming section 22 is wound around a wide paper tube 14L (i.e., a paper tube long in the axial direction) serving as a core through an adhesive (pickup paste).

[0081] The toilet paper 13L is wound around the paper tube 14L by a predetermined length to form a roll (log) that becomes a wide toilet roll 10L (i.e., having a large dimension in the CD direction), and the trailing end of the toilet paper 13L at the end of winding is cut by a cutter roll 31. The trailing end of the log at the end of winding is pasted onto the surface of the log (the outer peripheral surface of the roll) with an adhesive (tail seal paste) so as not to unwind, thereby forming the wide toilet roll 10L. The wide toilet roll 10L is then cut into individual toilet rolls 10 with a predetermined width according to product specifications and the like by a cutting section (not shown). Note that the above manufacturing method and manufacturing apparatus are just examples and do not limit the manufacturing method and applicable manufacturing apparatus according to the present invention.

[0082] For example, in the above example, two base web rolls 11R and 12R are mounted on the manufacturing apparatus of FIG. 4, and the sheets 11L and 12L are laminated within the apparatus of FIG. 4. However, the sheets 11L and 12L may be laminated in advance by another apparatus such as a winder or a plyer to form a two-ply base web roll, and this single two-ply base web roll may be mounted on the manufacturing apparatus of FIG. 4 to manufacture toilet rolls. Also, in the winding section 23, instead of the toilet roll 10L, a roll having a larger winding length than that is formed, and this is used as a secondary base web roll and mounted on another apparatus having a winding function such as a winder, and a toilet roll may be manufactured through the process of forming a log of a predetermined length.

[0083] <Manufacturing method of toilet roll according to an embodiment of the present invention> Thus, the method for manufacturing a toilet roll according to an embodiment of the present invention generally (a) a step of applying a single emboss to a laminated sheet formed by overlapping two sheets; (b) a step of applying a joining emboss to the laminated sheet to which the single emboss has been applied; (c) a step of forming a perforation for breaking on the laminated sheet to which the joining emboss has been applied; (d) a step of winding the laminated sheet on which the perforation for breaking has been formed into a roll so that the emboss recess of the single emboss faces the outside of the roll; and includes.

[0084] The manufacturing method according to an embodiment of the present invention may include, before the step (a), (x) a step of papermaking each of the two sheets; (y) a step of overlapping the two sheets to form a laminated sheet; and may include.

[0085] The manufacturing method according to an embodiment of the present invention may include, after the step (d), (z) a step of cutting the formed wide toilet roll to the product width; and may include.

[0086] Further, the manufacturing method according to an embodiment of the present invention may include other steps as necessary or may omit them as long as the effects of the present invention can be achieved.

[0087] In the step of applying the single emboss in the manufacturing method according to an embodiment of the present invention, the emboss depth of the emboss recess can be controlled by changing the emboss pressure condition for pressing the emboss roll against the laminated sheet (toilet paper).

[0088] (Advantages and effects) The toilet roll according to the present embodiment is a toilet roll in which two-ply toilet paper formed by overlapping two sheets is wound into a roll, the winding length of the toilet roll is 40 m or more and 100 m or less, The roll diameter of the toilet roll is 100 mm or more and 134 mm or less, and the basis weight per sheet is 11 g / m 2 or more and 20.5 g / m 2 or less, and the roll density of the toilet roll is 0.65 m / cm 2 or more and 2.05 m / cm 2 or less, and the toilet paper is provided with a single emboss on the entire paper surface and a joining emboss for preventing ply separation of two sheets, and is wound so that the emboss recess is on the outside of the roll, and the toilet paper is formed with perforations for breaking across the width direction of the toilet paper at regular intervals along the longitudinal direction of the toilet paper, and the emboss depths of the single emboss and the joining emboss are 0.8 mm or less.

[0089] According to the embodiment of the present invention having such a configuration, while the roll diameter of the roll is within a predetermined dimension, the roll length per roll is long, the softness of the toilet paper is ensured, and displacement of the perforations and ply peeling are prevented, and a two-ply toilet roll can be provided.

[0090] Therefore, according to the present invention, since the roll diameter of the toilet roll is within a predetermined dimension and the roll length per roll is long, space saving during carrying and storage can be achieved, and since the softness of the toilet paper is ensured, the usability is excellent, and since displacement of the perforations and ply peeling are prevented, a toilet roll that does not cause inconvenience during use can be provided. According to the present invention, in particular, regardless of the paper quality, for example, even when the smoothness of the sheet is high, a toilet roll in which displacement of the perforations and ply peeling are prevented can be provided.

[0091] (Second Embodiment) Referring to FIG. 5, a second embodiment of the present invention will be described. Unless otherwise specified, the configurations applicable to the first embodiment are applicable to this embodiment.

[0092] FIG. 5 is a front view for explaining a configuration example of toilet paper of a toilet roll according to a second embodiment of the present invention. In this example, the embossing pattern P of the embossed portion 13a of the toilet paper 13 is a collection of dots having a point-symmetric shape in which the embossed portions 13a are arranged concentrically, and is set to occupy a substantially square area with one side surrounded by a two-dot chain line being about 28.5 mm. Further, the embossing pattern P is provided such that its arrangement direction forms an inclination angle with respect to the width direction and the longitudinal direction of the toilet paper 13. In this example, the inclination angle of the arrangement direction of the embossing pattern P with respect to the width direction and the longitudinal direction is 7.5 degrees. Note that in the present invention, the inclination angle only needs to be not 0 degree and is not limited to 7.5 degrees.

[0093] As described above, in the second embodiment of the present invention, the embossing pattern P that is continuously repeated over the entire area of the toilet paper 13 is arranged such that its arrangement direction is inclined with respect to each of the width direction (CD direction, i.e., the left-right direction in the figure) and the longitudinal direction (MD direction, i.e., the up-down direction in the figure) of the toilet paper 13.

[0094] (Function and Effect) When the embossing pattern repeatedly formed over the entire area of the toilet paper is arranged along the width direction and / or the longitudinal direction of the toilet paper, in the toilet roll around which the toilet paper is wound, the embossed portions are likely to overlap in the radial direction of the roll so that they appear at the same position when viewed from the outer peripheral surface of the roll. When the embossed portions overlap, a phenomenon occurs in which the overlapping portions bulge out on the outer periphery of the roll. Due to the influence of the bulging portions, it becomes difficult to control the winding diameter of the roll small, and as a result, there is a limitation in increasing the winding length. Also, the tactile sensation when holding the toilet roll by hand becomes non-uniform over the outer periphery of the roll, and the softness of the roll decreases.

[0095] In contrast, in the embodiment of the present invention, the embossing pattern P on the paper surface of the toilet paper 13 is arranged so as to be inclined with respect to the width direction and the longitudinal direction of the toilet paper 13. According to this configuration, in the toilet roll 10 around which the toilet paper 13 is wound, the overlapping positions of the embossed portions 13a are dispersed on the outer peripheral surface of the roll. Thereby, the occurrence of the phenomenon that the stacked portions bulge out on the outer periphery of the roll is suppressed. Therefore, according to the present embodiment, when compared with a toilet roll other than the present embodiment having the same winding length, the effect of reducing the winding diameter of the roll is enhanced. Further, according to the present embodiment, when compared with a toilet roll other than the present embodiment having the same winding diameter, the winding length of the roll can be increased. Further, according to the present embodiment, the variation in the tightness of winding on the outer peripheral surface of the toilet roll 10 is reduced, and a soft roll can be obtained.

[0096] Note that the configuration of the embossing pattern P applicable to the present embodiment is not limited to the example shown in FIG. 5. For example, the embossing pattern P may be set to occupy a regular triangular region on the paper surface of the toilet paper 13, and the embossing pattern P may be arranged in a dense state. Further, the embossing pattern P may be one in which the embossed portions 13a are arranged in a spiral shape at regular intervals, or one in which the embossed portions 13a are arranged in a rotation target shape along an arbitrary curve.

[0097] <Preferred aspect of the embodiment of the present invention> The first and second embodiments of the present invention described above are widely applicable to a toilet roll having a roll winding length of 40 m or more and 100 m or less. Preferred aspects according to the roll winding length of the toilet roll are shown in more detail below.

[0098] (1) When the winding length of the toilet roll is 40 m or more and 60 m or less (a) The basis weight per sheet is 13.0 g / m 2 or more and 20.5 g / m 2The following, preferably 13.5 g / m 2 or more and 19.5 g / m 2 or less, more preferably 14.5 g / m 2 or more and 17.5 g / m 2 or less. (b) The winding density of the toilet roll is 0.65 m / cm 2 or more and 1.70 m / cm 2 or less, preferably 0.75 m / cm 2 or more and 1.55 m / cm 2 or less, more preferably 0.80 m / cm 2 or more and 1.40 m / cm 2 or less.

[0099] (2) When the winding length of the toilet roll is 60 m or more and 80 m or less (a) The basis weight per sheet is 12.0 g / m 2 or more and 18.5 g / m 2 or less, preferably 13.0 g / m 2 or more and 17.5 g / m 2 or less, more preferably 14.5 g / m 2 or more and 16.5 g / m 2 or less. (b) The winding density of the toilet roll is 0.85 m / cm 2 or more and 1.90 m / cm 2 or less, preferably 0.95 m / cm 2 or more and 1.70 m / cm 2 or less, more preferably 1.00 m / cm 2 or more and 1.55 m / cm 2 or less.

[0100] (3) When the winding length of the toilet roll is 80 m or more and 100 m or less (a) The basis weight per sheet is 11.0 g / m 2 or more and 17.0 g / m 2 or less, preferably 12.0 g / m 2 or more and 16.0 g / m 2 or less, more preferably 13.0 g / m 2 or more and 15.5 g / m2 It is as follows. (b) The winding density of the toilet roll is 1.05 m / cm 2 or more and 2.05 m / cm 2 or less, preferably 1.20 m / cm 2 or more and 1.95 m / cm 2 or less, more preferably 1.30 m / cm 2 or more and 1.80 m / cm 2 or less.

[0101] The present invention should be construed only from the matters described in its claims, and even in the above-described embodiments, any changes and modifications included in the concept of the present invention are possible other than the matters described. That is, all matters in the above-described embodiments are not for limiting the present invention, and can be arbitrarily changed according to the use, purpose, etc., including any configurations not directly related to the present invention.

Example

[0102] Using the same papermaking slurry (paper stock) having a pulp composition of 30% by mass of softwood bleached kraft pulp (NBKP): 70% by mass of hardwood bleached kraft pulp (LBKP), papermaking was carried out to obtain a plurality of parent roll reels on which the produced sheets were respectively wound. Using two of the parent roll reels, toilet rolls were manufactured according to the manufacturing equipment and manufacturing method shown in FIG. 4, and two-ply toilet rolls of Examples 1 to 3 shown in Table 1 were obtained. Here, as the embossing pattern and its arrangement of the single emboss, the pattern shown in FIG. 5 was used. For the toilet rolls of Examples 1 to 3, the following measurements and evaluations were performed. The measurement was carried out after conditioning the sample in an environment (temperature 23 ± 1°, humidity 50 ± 2% RH) according to Japanese Industrial Standard JIS P8111.

[0103] <Measurement> 〔Core diameter of paper tube [mm]〕 The outer diameter of the paper tube of the manufactured toilet roll was measured with a caliper and rounded off to the nearest whole number.

[0104] [Roll diameter of toilet roll [mm]] The outer roll diameter of the manufactured toilet roll was measured with a caliper and rounded off to the nearest whole number after the decimal point.

[0105] [Roll length of toilet roll [m]] While unwinding the toilet paper from the manufactured toilet roll, the length of the winding around the paper tube from the end portion to the start portion of the toilet paper was measured. The measurement was performed in 0.5 m increments and the fractional part was truncated.

[0106] [Winding density [m / cm 2 It was determined according to the following formulas (I) and (II). (Winding density) = (Roll length × Number of plies) ÷ (Cross-sectional area of toilet roll) (Formula I) (Cross-sectional area) = (Roll diameter DR of toilet roll ÷ 2) 2 × 3.14 - (Core diameter DC ÷ 2) 2 × 3.14 (Formula II)

[0107] [Grammage per sheet [g / m 2 Pull out the toilet paper from the toilet roll, and in accordance with Japanese Industrial Standard JIS P8124, measure the grammage of 2-ply toilet paper and divide it by 2 to obtain the grammage per sheet. Specifically, condition the 2-ply toilet paper according to the method specified in Japanese Industrial Standard JIS P8111, cut out the conditioned 2-ply toilet paper into a size of 10 cm × 10 cm with two sheets stacked, measure the weight of the cut-out 2-ply toilet paper, divide the weight by 0.01 m 2 of the cut-out area of the 2-ply toilet paper to measure the grammage of the 2-ply toilet paper, and divide the grammage by 2, the number of plies, to obtain the grammage per sheet.

[0108] [Embossing depth of single emboss [μm]] ​​In accordance with the above-described method of measuring and calculating the height difference of the emboss using a shape measurement laser microscope, the emboss depth (μm) of a single emboss was measured. The measurement was carried out at a portion corresponding to 10% of the roll length of the toilet roll, starting from the end of the toilet paper on the outer winding side of the roll (the position where the toilet paper 13 starts to be used in the toilet roll 10).

[0109] 〔Emboss depth [μm] of the joint emboss (edge emboss)〕 In accordance with the above-described method of measuring and calculating the height difference of the emboss using a shape measurement laser microscope, the emboss depth (μm) of the joint emboss (edge emboss) was measured. The measurement was carried out at a portion corresponding to 10% of the roll length of the toilet roll, starting from the end of the toilet paper on the outer winding side of the roll (the position where the toilet paper 13 starts to be used in the toilet roll 10).

[0110] <Evaluation> A sensory evaluation was performed on the following items, and the results were indicated by symbols (◎: excellent, 〇: good, △: acceptable, ×: unacceptable).

[0111] 〔Softness of the toilet paper〕 The softer the touch when stroking the skin with the toilet paper pulled out from the toilet roll, the higher the softness of the toilet paper was considered to be, and it was regarded as good. Specifically, those that felt painful when stroking the skin were rated as unacceptable (×), those that did not feel painful but felt firm were rated as acceptable (△), those that felt soft were rated as good (〇), and those that felt extremely soft were rated as excellent (◎).

[0112] 〔Ply separation and misalignment of the perforations〕 The toilet roll was rotatably held by a holder, and the toilet paper was pulled out from the toilet roll by 50 cm at a time, and then the toilet paper was repeatedly broken at the perforation position of the sheet on the outer side of the roll to check for the presence or absence of ply separation between two sheets of 2-ply and the presence or absence of misalignment of the perforations.

[0113] Those with no ply separation between the two sheets were rated excellent (◎), those with a little ply separation but still usable without problems were rated good (〇), those with ply separation but still usable with some inconvenience were rated fair (△), and those with severe ply separation where the two sheets fell apart and were difficult to handle integrally were rated poor (×).

[0114] Those with no misalignment of the perforations between the two sheets were rated excellent (◎), those with a little misalignment of the perforations but still able to cleanly break the toilet paper at the perforation position were rated good (〇), those with misalignment of the perforations but still able to break the two sheets at the perforation position with some effort by applying shear force little by little were rated fair (△), and those with a large misalignment of the perforation position and unable to cleanly break at the perforation position were rated poor (×). Table 1 shows the test results.

[0115]

Table 1

[0116] As shown in Table 1, in Examples 1 to 3 where the roll lengths were 50 m, 60 m, and 90 m respectively, the roll diameters were all between 100 mm and 134 mm. That is, the roll diameters of Examples 1 to 3 were of a size that could be rotatably accommodated in a general toilet roll holder, and the roll diameters of Examples 1 to 3 were longer than the conventional mainstream roll length of 30 m, achieving space savings during roll handling and storage.

[0117] Also, in Examples 1 to 3, where the roll density increased as the roll length increased, the embossing depth of the single emboss applied across the entire paper surface was set low at 0.8 mm or less. As a result, without significantly reducing the basis weight per sheet, it was possible to control the roll diameter to be small while ensuring the softness of the toilet paper.

[0118] In addition, in Examples 1 to 3, edge embossing was applied respectively, and the phenomena of primer peeling and misalignment of perforations were prevented.

Explanation of Signs

[0119] 10 Toilet roll 11, 12, 11L, 12L Sheet 11R, 12R Parent roll 13, 13L Toilet paper 13a Embossed part 13b Joining embossed part (edge embossed part) 14, 14L Core (paper tube) 20 Parent roll stand 21 Embossing part 21A Embossing roll unit 21B Joining embossing roll unit 22 Perforation forming part 23 Winding part 24 Embossing roll 25 Backup roll 26 Joining embossing wheel 27 Receiving roll 28c Comb-shaped cutter 28h Rotary blade holder 29c Linear cutter 29h Fixed blade holder 30 Superposition roller 31 Cutter roll D Embossing depth DC Core diameter DR Winding diameter P Embossing pattern a, b Longest part

Claims

1. A toilet roll in which two sheets of toilet paper are overlapped and wound into a roll, The roll length of the toilet roll is 40 m or more and 100 m or less, The roll diameter of the toilet roll is 100 mm or more and 134 mm or less, The basis weight per sheet is 11 g / m 2 20.5g / m or more 2 is as follows: The winding density of the toilet roll is 1.02 m / cm 2 1.48m / cm or more 2 is as follows: The toilet paper has a single embossment on the entire surface and a joining embossment for preventing the ply separation of the two sheets, and is wound up so that the embossed recess is on the outside of the roll; The toilet paper has tearing perforations that cross the width of the toilet paper at regular intervals along the longitudinal direction of the toilet paper, The embossing depth of the single embossing is 115 μm or more and 127 μm or less, The toilet roll according to claim 1, wherein the embossing depth of the bonding embossments is 124 μm or more and 143 μm or less.

2. The roll length of the toilet roll is 40 m or more and 60 m or less, The basis weight per sheet is 13.0 g / m 2 20.5g / m or more 2 2. The toilet roll according to claim 1, characterized in that:

3. The roll length of the toilet roll is 60 m or more and 80 m or less, The basis weight per sheet is 12.0 g / m 2 18.5g / m or more 2 2. The toilet roll according to claim 1, characterized in that:

4. The roll length of the toilet roll is 80 m or more and 100 m or less, The basis weight per sheet is 11.0 g / m 2 17.0g / m or more 2 2. The toilet roll according to claim 1, characterized in that:

5. The toilet roll according to any one of claims 1 to 4, characterized in that the embossed pattern of the single embossing is a collection of dots set to occupy a predetermined area, and the arrangement direction of the dots is arranged at an inclined angle with respect to the width direction and the longitudinal direction of the toilet paper.

6. A method for producing a toilet roll, comprising the steps of: A step of performing single embossing on a laminated sheet formed by overlapping two sheets; applying a bonding embossment to the laminated sheet on which the single embossing has been applied; forming a tear perforation in the laminated sheet on which the bonding embossing has been applied; A step of winding up the laminated sheet having the tear perforations formed thereon into a roll such that the embossed recess of the single embossing is on the outside of the roll; Including, In the single embossing step, an embossing roll is pressed against the surface of the laminated sheet that is to be on the outer side of the roll to form embossed recesses having an embossing depth of 115 μm or more and 127 μm or less on the surface; A method for manufacturing a toilet roll, characterized in that in the step of applying the bonding embossment, the bonding embossment is formed so that the embossment depth of the bonding embossment is 124 μm or more and 143 μm or less.

7. 7. The method for manufacturing a toilet roll according to claim 6, wherein the embossing roll has an embossing pattern which is a collection of dots set to occupy a predetermined area, and the arrangement direction of the embossing pattern is arranged at an inclined angle with respect to the width direction and the length direction of the laminated sheet.

8. The method for producing a toilet roll according to claim 6 or 7, wherein the toilet roll is a toilet roll according to any one of claims 1 to 5.

Images