Toilet roll

Abstract

To provide a toilet roll which satisfies softness in spite of being a long wound article and is hardly broken.SOLUTION: A toilet tissue roll obtained by winding a stack of two plies of sanitary tissue paper, wherein the basis weight per ply is 10.0 to 15.0g / m2, the paper thickness per ply is 60 to 95 μ m, the outer diameter of the paper tube is 20 to 45 mm, the winding length per two plies is 60 to 90 mm, the tensile modulus per ply is 6.0 to 16.0N / m2, the work of rupture is 3.0 to 6.0N·m, and embossing is formed. 2.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a toilet roll. [Background technology]

[0002] There are various toilet rolls on the market that differ in factors such as the number of plies, whether or not embossed, basis weight, paper thickness, roll length, and roll density.

[0003] One of these is a group of products called long rolls. That is, the basis weight per ply is not so low, and although it is two-ply, the roll length is long and double embossed to give it a soft feel. An example of this is the product in Patent Document 1. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-188342 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in this type of long rolled product, the sheet tends to become thin and hard, which not only impairs the necessary properties such as softness but also makes the sheet more susceptible to breakage.

[0006] Therefore, a main object of the present invention is to provide a toilet roll that is soft enough and resistant to breaking even when rolled in a long length. [Means for solving the problem]

[0007] In order to solve the above problems, the present invention provides a roll of two plies of sanitary tissue paper, Basis weight per ply: 10.0-15.0g / m 2The paper thickness per ply is 60 to 95 μm, the outer diameter of the paper core is 20 to 45 mm, and the winding length for two plies is 60 to 90 m. Furthermore, the tensile modulus of one ply is 6.0 to 16.0 N / mm 2 , the work of breaking is 3.0 to 6.0 N·mm, The embossment is formed, This toilet roll is characterized by the following: Here, the tensile modulus and work at break are values ​​measured in the longitudinal direction of the fiber, and are values ​​measured on a 25 mm wide sample with a gripping jig distance of 50 mm in a tensile tester at a pulling speed of 10 mm / min. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a toilet roll that is long and yet has satisfactory softness and is difficult to break. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 10 is a diagram showing the results of a tensile test in Comparative Example 1. [Figure 2] FIG. 2 is a diagram showing the results of a tensile test in Example 1. [Figure 3] FIG. 1 is a schematic perspective view of a toilet roll. [Figure 4] FIG. 10 is a plan view of an example of an embossing pattern. [Figure 5] FIG. 5 is a cross-sectional view of a main part taken along the line in FIG. 4. DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention will be described in more detail below with reference to embodiments thereof.

[0011] As shown in FIG. 3, the toilet roll according to the present invention is a toilet roll 1 made by winding a strip of toilet paper 10 around a paper tube (also called a tube core) 20 in a roll shape.

[0012] This toilet paper is made from 100% virgin pulp by mass as its fiber material, but can also contain recycled paper pulp. For example, the fiber material can be 30 to 70% by mass of virgin pulp and 30 to 70% by mass of recycled paper pulp. Recycled paper pulp is cheaper than virgin pulp, and by blending recycled paper pulp, it can be produced more cheaply than a product made of 100% virgin pulp.

[0013] Although the recycled paper pulp is not necessarily limited, it is particularly desirable to use high-quality recycled paper pulp (also known as F-DIP, high-quality recycled paper pulp, or high-quality deinked pulp) made from high-quality recycled paper. High-quality recycled paper pulp is made from selected high-quality recycled paper, such as high-quality paper, colored high-quality paper, and slightly glossy paper, and contains a large amount of hardwood kraft pulp (LBKP) derived from the raw material. This makes it easy to develop paper strength, and in particular, makes it extremely easy to configure the toilet paper's basis weight, paper thickness, dry tensile strength, roll diameter, and roll density.

[0014] The toilet paper according to the present invention has the above-mentioned fiber material composition and its basis weight (basis weight per ply) is 10.0 to 15.0 g / m 2 , especially 11.0 to 14.0 g / m 2 First, if the basis weight is too small, it is difficult to achieve the required strength and thickness. Also, if the basis weight is too large, the paper thickness becomes too thick, making it difficult to achieve the desired compact reel diameter. The basis weight is a value measured based on JIS P 8124 (1998).

[0015] The paper thickness per ply is set to 60 to 95 μm, with 70 to 90 μm being particularly desirable. If the paper thickness is too thin, it is difficult to ensure the necessary strength, and the paper loses stiffness, resulting in a lack of texture, particularly a soft feel. Furthermore, it is difficult to achieve an appropriate roll diameter and tightness for the finished product. Conversely, if the paper thickness is too thick, it becomes difficult to achieve the desired roll diameter, making compactness difficult to achieve.

[0016] To measure paper thickness, the test piece is thoroughly conditioned (usually for about 8 hours) under the conditions specified in JIS P 8111 (1998), and then measured in single-ply form using a PEACOCK G-type dial thickness gauge (thickness measuring device) (manufactured by Ozaki Seisakusho) under the same conditions. Specifically, after ensuring that there is no dirt or dust between the plunger and the measuring table, the plunger is lowered onto the measuring table, the dial thickness gauge's scale is moved to set the zero point, the plunger is then raised, the sample is placed on the test table, and the plunger is slowly lowered, and the gauge reading is taken. At this time, the plunger is simply placed on the test table. The plunger terminal is made of metal, and its circular flat surface with a diameter of 10 mm is placed perpendicular to the paper surface. The load during paper thickness measurement is approximately 70 gf. The paper thickness is measured as the average value obtained by performing 10 measurements. The dry tensile strength in this invention is specified in JIS P 8113.

[0017] The outer diameter of the paper tube is preferably 20 to 45 mm, especially 35 to 45 mm. The outer diameter of the paper tube is not fundamentally related to the characteristics of the toilet paper, but is determined by factors related to the winding length and winding density of the two-ply.

[0018] The winding length for two plies is 60 to 90 m, and 65 to 85 m is particularly desirable.

[0019] The toilet paper in this embodiment is made from a fiber material composition of virgin pulp and recycled paper pulp blended in as needed, and has a specific basis weight, paper thickness, paper core outer diameter, and two-ply winding length, so that despite its long length, it can easily fit into a commercially available toilet roll holder and is easy to remove from the holder. The "fit" and "ease of removal" are evaluated as "ease of hooking" and "ease of turning" in the test results described below.

[0020] The toilet paper of the present invention has a tensile modulus of elasticity of 6.0 to 16.0 N / mm per ply. 2 , more preferably 6.5 to 10.0 N / mm 2The breaking force is 3.0 to 6.0 N·mm, more preferably 3.5 to 5.5 N·mm, and the paper satisfies the softness requirement and is difficult to break. Here, the tensile modulus and work at break are values ​​measured in the longitudinal direction of the fiber, and are values ​​measured on a 25 mm wide sample with a gripping jig distance of 50 mm in a tensile tester at a pulling speed of 10 mm / min.

[0021] In addition, it is more desirable that the elongation at break is 6.0 to 12.0%.

[0022] There are commercially available long-length products that have similar basis weights and thicknesses, but the tensile modulus and work of rupture of these products are different.

[0023] Typically, the tensile test results for Comparative Example 1 are shown in FIG. 1, whereas the tensile test results for Example 1 are shown in FIG.

[0024] A supplementary explanation regarding this test is provided below. That is, when a toilet paper sheet is gently touched, if the sheet is stretchy, the stress from the sheet is reduced and the user feels that the sheet is soft. In this way, assuming "gently touching the sheet," the optimum way to judge the quality of a sheet is to obtain the tensile modulus value at a displacement of 0, with the tensile speed of the gripping jig in the tensile tester set to 10 mm / min. The displacement of 0 is defined as the point where the elongation (stroke) is 0 when a load of 0.2 N is applied using a 25 mm wide sample in accordance with JIS P 8113. Typically, tensile strength is measured at a pulling speed of 100 mm / min, and the breaking elongation is higher in Comparative Example 1. This is because the breaking strength of the sheet is high, and the sheet (paper quality) is hard, which differs from the elongation of the soft sheet shown in Example 1, as shown in Figure 2.

[0025] Similarly, the work to break at a tensile speed of 10 mm / min was higher in Example 1 than in Comparative Example 1, and it can be said that the material is less likely to break due to elongation.

[0026] Tensile modulus of elasticity per ply: 6.0 to 16.0 N / mm 2 A sheet with a breaking work of 3.0 to 6.0 N·mm can be said to be a paper that satisfies the softness requirement and is difficult to break. In fact, the evaluation based on the tensile modulus and work at break values ​​has a high correspondence with the sensory evaluation, as will be shown in the test evaluation described later.

[0027] As a means for obtaining a toilet roll that is long yet has sufficient softness and is difficult to break, for example, a method of operating the machine by using a calender in a ply machine to iron the crepe shape so that the elongation of the crepe is maintained even after processing, or a method of embossing can be exemplified.

[0028] Regarding embossing, further examples include the ridges of the embossing partially destroying the fibers relative to the overall flow, making the material more likely to stretch and shrink under small loads (provisionally called "Mount Fuji embossing"); and the embossing can be double embossed. When double embossing is used, there are gaps between the sheets and both the front and back surfaces are smooth, resulting in a soft and smooth quality.In contrast, with single embossing, which is commonly used for long products, it is difficult to obtain a product with sufficient softness, as will be shown in the test examples described below.

[0029] In the present embodiment, the winding density of the toilet roll is preferably 1.0 to 1.8, and particularly 1.2 to 1.7. When the winding density is low, the roll is wound loosely and the texture can be maintained, but the winding length is short compared to the roll diameter, resulting in excessive logistics costs. Conversely, when the winding density is high, the texture deteriorates significantly. The winding density is calculated as described below.

[0030] On the other hand, the toilet paper of the present invention can be blended with a softener to adjust paper strength and improve surface properties. However, the softener here is not an externally applied softener, such as a moisturizer or lotion, but is an internally added softener to the papermaking raw material. Externally applied softeners, such as lotions, reduce paper strength upon application, making it difficult to wind the paper at high tension for compacting, making production extremely difficult. Furthermore, it is difficult to achieve the desired winding density and low cost. The blending amount of softener is preferably 0.8 to 2.0 kg / t. A preferred softener contains a nonionic surfactant (component A) having an alkyl group and / or an alkenyl group and a cationic surfactant (component B) having an alkyl group and / or an alkenyl group. It is particularly desirable for the nonionic surfactant (component A) to have an alkyl group having 6 to 24 carbon atoms and / or an alkenyl group having 6 to 24 carbon atoms as the hydrophobic moiety. If the carbon number of the A component is less than 6, the softening effect may not be enhanced, and if the carbon number exceeds 24, dispersibility may be poor when added to a papermaking system.

[0031] Furthermore, when producing the toilet paper according to the present invention, the fiber raw material can be beaten as appropriate, but in the case of the toilet paper according to the present invention, the beating operation can be omitted by blending recycled paper pulp.

[0032] The crepe ratio during papermaking can also be set appropriately. A crepe ratio of 15 to 27% is preferred, and 18 to 23% is more preferred. When processing into a roll, the winding diameter may be adjusted by draw or tension, so by setting the crepe ratio within the above range, the paper is less likely to tear even when moderate draw or tension is applied, and the paper does not become excessively thick, which is preferable.

[0033] Furthermore, it is desirable that the toilet paper be embossed. This embossing can be any suitable embossing pattern, such as microembossing, dot embossing, or design embossing. However, when embossing is applied, the depth of the embossing pattern is desirably 1.90 mm or less, and more desirably within the range of 0.7 mm to 1.90 mm. If the depth is deeper than 1.90 mm, compactification becomes difficult. Furthermore, if the depth of the embossing is shallower than 0.75 mm, the bulkiness and design characteristics of the embossing tend to be insufficient. Note that the dimensions of the embossing are the actual dimensions of the convex portions formed on the embossing (metal) roll, and do not relate to the embossing imparted to the actual paper, since the mating surface of the embossing roll is an elastic roll such as rubber. A preferred example of embossing is the aforementioned "Mt. Fuji embossing," in which recesses with square bases are arranged so that each vertex of the square base of one recess is connected to the vertex of the square base of the adjacent recess by a valley line. This embossing is likely to produce the desired effect of obtaining a soft and smooth sheet.

[0034] A specific example of the aforementioned "Mt. Fuji embossing" is shown below. As shown in Figures 4 and 5, the "Mount Fuji embossing" has square-bottom recesses 40, 40 arranged in a grid pattern across the entire surface of the paper at a predetermined center-to-center spacing L9, and valley grooves 41, 41... formed to connect the four corners of the bottom surface. It is particularly desirable for the "Mount Fuji embossment" to have a rectangular bottom surface measuring 1.0 to 1.5 x 1.0 to 1.5 mm, a center-to-center spacing L9 of 4.5 to 5.5 mm, and the recesses 50, 50... to be arranged in a grid pattern at an angle of 40° to 50° relative to the width direction (the angle is indicated by the symbol ∠B in Figure 4).

[0035] It is possible to impart the "Mount Fuji embossing" in a so-called single embossing form, in which a recess on one side becomes a protrusion on the other side, but it is preferable to use a so-called double embossing form, in which recesses are formed on both sides.

[0036] The toilet roll according to the present invention can be manufactured by winding toilet paper base paper obtained in a papermaking process in accordance with a known manufacturing procedure. More specifically, in a paper tube forming process for manufacturing a long paper tube, a long paper tube is manufactured, the toilet paper manufactured in the papermaking process is wound around this long paper tube to manufacture a log, and this log is then cut in the width direction to the product width (the width of symbol L3 in Figure 1) to form individual toilet rolls. In particular, when manufacturing the log, the toilet roll can be manufactured by adjusting the tension when winding the toilet paper around the paper tube. [Example]

[0037] Next, examples and comparative examples of the toilet roll of the present invention will be shown to clarify the effects of the present invention.

[0038] The constitution of the toilet roll and the physical properties and composition of the toilet paper for each example are as shown in Table 1 below.

[0039] The fiber material is 30% softwood kraft pulp (NBKP) and 70% hardwood kraft pulp (LBKP).

[0040] The embossing was performed using the "Mt. Fuji embossing" described above, and the embossing pattern depth was 1.45 mm. Calendering was carried out on the paper machine and on the ply machine.

[0041] The evaluation involved 20 test subjects actually using each example of toilet paper for one week, and then making absolute ratings on a seven-point scale for each of the following categories: softness, smoothness, moistness, fluffiness, and tear resistance. The evaluation criteria were as follows: 7 points: very good, 6 points: good, 5 points: somewhat good, 4 points: neutral, 3 points: somewhat bad, 2 points: bad, 1 point: very bad.

[0042] The measurement methods for the values ​​in the table are as follows.

[0043] [Yonetsubo] Measurement was carried out in accordance with JIS P 8124 (1998).

[0044] [Paper thickness] The thickness was measured according to the above-mentioned thickness measurement method using a dial thickness gauge (thickness measuring instrument) "PEACOCK G type" (manufactured by Ozaki Seisakusho) under the conditions of JIS P 8111 (1998).

[0045] [Roll winding density] = theoretical cross-sectional area / roll cross-sectional area Roll cross-sectional area = Cross-sectional area of ​​entire roll - Cross-sectional area of ​​paper tube Theoretical cross-sectional area = paper thickness x roll length

[0046] [Tensile strength and elongation at break] Tensile speed (vertical) 100mm / min, (horizontal) 50mm / min, sample width 25mm, Distance between gripping jigs: 100 mm, Strength and elongation at break measured for two plies Measurement tester: Minebea Co., Ltd. "Tension and compression tester TG-200N"

[0047] [Tensile modulus (vertical)] The tensile speed was 10 mm / min, the sample width was 25 mm, and the distance between the gripping jigs was 50 mm. Measurements were made five times for one ply, and the average value was taken as the tensile modulus. Measurement tester: Shimadzu Corporation "EZS-20NX" Software: "TRAPEZIUMX"

[0048] [Work of Breaking (Vertical)] The integrated value of the load-displacement curve obtained for one ply at a tensile speed of 10 mm / min, sample width of 25 mm, and distance between gripping jigs of 50 mm. Measurement tester: Shimadzu Corporation "EZS-20NX" Software: "TRAPEZIUMX"

[0049] [Table 1]

[0050] [Table 2]

[0051] Table 2 contains an example called "Reference Example," which is so named because, even though it falls within the scope of the present invention, it is not rated high enough.

[0052] From these comparative examples and examples, it can be said that by adopting the configuration of the present invention, it is possible to produce a toilet roll that is soft enough and difficult to break even when rolled into a long length. [Explanation of symbols]

[0053] 1...toilet roll, 10...toilet paper, 20...paper tube (core), L1...toilet roll roll diameter, L2...toilet roll core diameter, L3...toilet roll width.

Claims

1. Two plies of sanitary tissue paper are stacked and wound up, Basis weight per ply: 10.0 to 15.0 g / m ２ The paper thickness per ply is 60 to 95 μm, the outer diameter of the paper tube is 20 to 45 mm, and the winding length for two plies is 60 to 90 m, Furthermore, the tensile modulus of one ply is 6.0 to 16.0 N / mm ２ , the breaking work is 3.0 to 6.0 N mm; An embossment is formed on each of the plies, and these plies are laminated to form a double embossment. A toilet roll characterized by: Here, the tensile modulus and work at break are values ​​measured in the longitudinal direction of the fiber, and are values ​​measured on a 25 mm wide sample at a gripping jig distance of 50 mm in a tensile tester and a pulling speed of 10 mm / min.

2. Basis weight per ply: 11.0 to 14.0 g / m ２ The toilet roll according to claim 1,

3. The toilet roll according to claim 1, wherein the breaking elongation is 6.0 to 12.0%.

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