Hygienic paper tissue

Abstract

To provide a sanitary paper with a small number of crushed, collapsed, and reversed recesses. A sanitary paper is provided by a double-layered double-embossed sanitary paper roll in which a first paper layer having recesses and protrusions corresponding to the recesses formed by embossing and a second paper layer having recesses and protrusions corresponding to the recesses formed by embossing are stacked with the protrusion-forming surfaces facing each other, and wound around a paper tube, wherein the sanitary paper has a roll length of 45 m or more, a roll diameter of 110 mm to 130 mm, a winding density of 0.75 to 1.6, a weight per unit area of each layer of 11.0 g / m 2 18.0 g / m 2 , a double-layered paper thickness of 125 μm to 205 μm, a paper thickness of the first paper layer of 65 μm to 120 μm, and an embossing pattern of the first paper layer having recesses arranged at a prescribed interval on a straight line, and valleys shallower than the recesses and extending from the recesses in four directions and connecting between the recesses, and the arrangement direction of the recesses and the extension direction of the valleys are not in line with the flow direction of the sanitary paper.

Description

Technical Field

[0001] This invention relates to a toilet paper roll made by winding strips of toilet paper into a roll. Background Technology

[0002] Toilet paper rolls are available in various roll lengths to cater to consumer preferences. For example, known products include: rolls made of double-layered toilet paper with a length of approximately 25-30 m, also referred to as standard or regular rolls; rolls 1.5 times the length of the standard roll (approximately 37.5-45 m); rolls twice the length of the standard roll (approximately 50-60 m); and rolls three to three and a half times the length of the standard roll (approximately 75-90 m), etc. (see Patent Document 1 below). It should be noted that products exceeding 1.5 times the roll length are sometimes referred to as long-size products, etc.

[0003] On the other hand, there are toilet paper rolls made by rolling toilet paper with raised or recessed surfaces created through embossing. Regarding the raised or recessed shape of toilet paper, in relation to the embossing process, there are known types called single-embossed and double-embossed.

[0004] Generally speaking, single embossing refers to the embossing process that forms a concave portion on one side and a corresponding convex portion on the other side; double embossing refers to the embossing process that forms multiple layers of paper with a concave portion on one side and a corresponding convex portion on the other side (see Patent Documents 1 to 4 below).

[0005] Double-embossed toilet paper is typically stacked with the concave surfaces of each paper layer forming the outer surface. Compared to single-embossed toilet paper, both the front and back are smoother, the difference in skin feel between the front and back is smaller, and gaps are formed between the paper layers, so it is superior in terms of being fluffy and soft (see Patent Document 4 below).

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Application Publication No. 2020-179882

[0009] Patent Document 2: Japanese Patent Application Publication No. 2022-066267

[0010] Patent Document 3: Japanese Patent Application Publication No. 2023-065593

[0011] Patent Document 4: Japanese Patent Application Publication No. 2021-053249 Summary of the Invention

[0012] The technical problem that the invention aims to solve

[0013] However, it was found that in toilet paper rolls made of double-embossed toilet paper, especially when the roll length increases, there are many parts where the concave part is crushed or collapsed, and parts where the concave part is reversed into a convex shape.

[0014] Furthermore, it can be seen that in such sections, the surface smoothness decreases and the fluffiness and softness are reduced. It can also be further seen that the formation of such sections results in variations in the clarity of the recesses, or the formation of longitudinal wrinkles along the winding direction, thus leading to a decrease in the overall appearance.

[0015] In particular, the toilet paper disclosed in Patent Document 4, which has recesses arranged at predetermined intervals along the winding direction and forms an embossed pattern with grooves connecting the four corners of the recesses, although the grooves make the toilet paper easy to stretch and are suitable for lengthening the roll length of double-embossed toilet paper, the aforementioned problem of recess collapse still occurs even in such an embossed pattern where the recesses are connected by grooves.

[0016] Therefore, the main objective of this invention is to improve the crushing, collapse, and formation of concave portions that turn into convex portions in toilet paper rolls made from double-embossed toilet paper, and to provide a toilet paper roll with excellent smoothness and fluffy softness.

[0017] Technical means for solving problems

[0018] The first means to solve the above problems is

[0019] A toilet paper roll is formed by stacking a first paper layer and a second paper layer with their convex surfaces facing each other, and then winding them onto a paper tube. The first paper layer has a concave portion formed by embossing and a corresponding convex portion located on the outer surface of the roll; the second paper layer has a concave portion formed by embossing and a corresponding convex portion located on the inner surface of the roll. The toilet paper roll is characterized in that... The aforementioned toilet paper rolls have a length of 45 m or more, a diameter of 110 mm to 130 mm, and a winding density of 0.75 to 1.6. The aforementioned toilet paper has a unit area weight of 11.0 g / m² per ply. 2 ~18.0 g / m 2 The thickness of the double-layer paper is 125 μm to 205 μm, and the thickness of the first paper layer is 65 μm to 120 μm; and At least the first paper layer has an embossed pattern with recesses arranged at predetermined intervals in a straight line, and grooves that are shallower than the recesses and extend in all directions from the recesses to connect the recesses, and the arrangement direction of the aforementioned recesses and the extension direction of the aforementioned grooves are not consistent with the flow direction of the toilet paper.

[0020] The second method is a toilet paper roll of the first method described above, wherein the angle between the arrangement direction of the concave portions and the flow direction of the toilet paper is 10 degrees to 45 degrees or -10 degrees to -45 degrees.

[0021] The third method is a toilet paper roll made using the first or second method described above, wherein the concave portion of the first paper layer is quadrilateral or four-pointed star in shape, and the grooves extend from the four vertices of the aforementioned concave portion.

[0022] The fourth method is a toilet paper roll made using the third method described above, wherein the interval between the recesses of the first paper layer is 5.05 mm to 5.35 mm.

[0023] The fifth method is a toilet paper roll made using the third or fourth method described above, wherein the width of the recess in the first paper layer is 1.15 mm to 1.31 mm.

[0024] Invention Effects

[0025] According to the present invention, the crushing, collapse, and formation of concave portions turning into convex portions in toilet paper rolls made from double-embossed toilet paper can be improved, providing a toilet paper roll with excellent smoothness and fluffy softness. Attached Figure Description

[0026] Figure 1 This is a perspective view of a toilet paper roll used to illustrate the present invention.

[0027] Figure 2 This is a top view illustrating the embossed pattern of the first paper layer of the present invention.

[0028] Figure 3 This is a top view of the shape used to form the recess of the present invention.

[0029] Figure 4 This is a top view illustrating other embossed patterns on the first paper layer of the present invention.

[0030] Figure 5 This is a top view illustrating another embossed pattern of the first paper layer of the present invention.

[0031] Figure 6 This is a top view illustrating another embossed pattern on the first paper layer of the present invention.

[0032] Figure 7 yes Figure 2Schematic diagrams of sections II, II-II, and III-III.

[0033] Figure 8 It is a top view used to illustrate the measurement location of the cross-sectional curve of the concave part.

[0034] Figure 9 It is shown Figure 8 A diagram showing examples of ripple curves at positions A1-A1 and A2-A2.

[0035] Figure 10 It is shown Figure 8 A diagram showing examples of ripple curves at positions B1-B1 and B2-B2.

[0036] Figure 11 This is a top view illustrating the embossed pattern of the second paper layer of the present invention.

[0037] Figure 12 This is a top view illustrating the overlap between the recesses of the first paper layer and the recesses of the second paper layer in this invention.

[0038] Figure 13 This is a diagram used to illustrate the toilet paper used in the comparative example. Detailed Implementation

[0039] Next, refer to Figures 1 to 12 The embodiments of the present invention will be described in detail below.

[0040] like Figure 1 As shown, the toilet paper roll 1 of this embodiment is a double-layered hydrolyzable toilet paper 10 formed by stacking two paper layers, a first paper layer 11 and a second paper layer 12, and is wound around a paper tube (also called a core) 20, and is cylindrical in shape. In the toilet paper roll 1 of this embodiment, the toilet paper 10 is wound with the first paper layer 11 as the outer surface side and the second paper layer 12 as the inner surface side.

[0041] In toilet paper rolls, the roll length of products referred to as double-layer regular or standard products is approximately 25 m to 30 m. However, the roll length of toilet paper roll 1 in this embodiment is 45 m or more in a double-layer structure, which can form product groups referred to as long-size products, such as 1.5x rolls, 2x rolls, 3x rolls, and 3.2x rolls. From the perspective of its relationship with the effects of the present invention, the upper limit of the roll length is expected to be 125 m, which is suitable for long-size products with a roll length of 4 to 4.2 times that of product groups such as regular or standard products.

[0042] The roll diameter L2 of the toilet paper roll 1 in this embodiment is 110 mm to 130 mm, preferably 110 mm to 120 mm. The holder for holding the toilet paper roll is generally manufactured based on JIS P 4501 with 120 mm as a reference. The roll diameter of the toilet paper roll in this embodiment is 110 mm to 130 mm, allowing it to be placed on a standard holder. Furthermore, if the roll length is set to less than 110 mm due to its length, the toilet paper will be tightly wound, potentially reducing its quality, such as its feel against the skin. Here, the roll diameter L2 is a value measured using a diameter gauge manufactured by MURATEC-KDS Co., Ltd., or a similar device. It should be noted that the roll width L1 of the toilet paper roll 1 in this embodiment is not limited, but is preferably 100 mm to 120 mm. Additionally, the outer diameter L3 of the paper tube 20 is not limited, but is preferably 36 mm. mm~42 mm.

[0043] The toilet paper 10 of the toilet paper roll 1 in this embodiment is a double-layer toilet paper 10 formed by stacking a first paper layer 11 and a second paper layer 12 with concave and convex shapes formed by embossing. In addition, the toilet paper 10 is a double-embossed toilet paper 10 formed by stacking the first paper layer 11 and the second paper layer 12, wherein the first paper layer 11 and the second paper layer 12 each have a concave and convex shape with a concave portion 32 on one side and a convex portion 31 corresponding to the concave portion 32 on the other side, and each paper layer is stacked with the convex portion forming surfaces facing each other, and the first paper layer 11 is located on the outer surface side of the roll and the second paper layer 12 is located on the inner surface side of the roll.

[0044] It should be noted that the toilet paper 10 of this embodiment is not a so-called laminated embossed form where the outer and inner paper layers are bonded together with an adhesive. That is, the first paper layer 11 and the second paper layer 12 are not bonded together with an adhesive or the like. In order to prevent interlayer peeling, the first paper layer 11 and the second paper layer 12 are preferably integrated by interlayer pressing methods such as contact embossing, edge embossing, and knurling.

[0045] The unit area weight of the first paper layer 11 and the second paper layer 12 of the toilet paper 10 in this embodiment, that is, the unit area weight of each layer, is 11.0 g / m². 2 ~18.0 g / m 2 The preferred value is 12.0 g / m 2 ~17.0 g / m 2If the unit area weight of the first paper layer 11 and the second paper layer 12 is within this range, it can sufficiently satisfy the skin-like feel, softness, and fluffiness required for long-size products, and long-size products with rolls of 1.5 to 4.2 times the width, while also improving the formation of crushed, collapsed, and convex portions in concave areas. The unit area weight can be adjusted by, for example, the unit area weight of the fibers and the wrinkling rate. The desired difference in unit area weight between the first paper layer 11 and the second paper layer 12 is 0.5 g / m². 2 Within this range, the difference in tensile strength and stiffness between the outer and inner surfaces of the winding is minimized. Furthermore, the weight per unit area is expected to be further adjusted based on the roll length, with a desired weight per unit area of ​​16.0 g / m² for products with roll lengths of 1.5 times and 2 times the roll length. 2 ~17.0 g / m 2 For products with roll lengths of 3x, 3.2x, and 4.2x, the weight per unit area is set at 11.0 g / m². 2 ~13.0 g / m 2 .

[0046] The thickness of the double-layered toilet paper 10 in this embodiment is 120 μm to 205 μm, preferably 125 μm to 200 μm. Within this thickness range, the required thickness and fluffiness for long-size products with a roll diameter of 1.5 to 4.2 times the aforementioned roll diameter can be sufficiently satisfied. The paper thickness can be adjusted, for example, by adjusting the presence or absence of calendering, calendering pressure, embossing process, and wrinkle rate.

[0047] In particular, in the toilet paper 10 of this embodiment, the thickness of the first paper layer 11 is 65 μm to 120 μm. Since the first paper layer 11 is located on the outer surface of the roll, it becomes the side from which the appearance, etc., resulting from the embossing process can be visually identified. At the same time, the tension on the outer surface of the roll during the roll winding is slightly greater than that on the second paper layer 12 on the inner surface of the roll winding. Especially in long-size products, it is stretched more forcefully during the roll winding and after the roll is formed compared to conventional products. In the toilet paper roll 1 of this embodiment, by setting the thickness of the first paper layer 11 to 65 μm to 120 μm, combined with other components of the present invention such as the unit area weight and the embossing pattern described later, it is possible to improve the crushing, collapse, and formation of the portion of the concave 32 that reverses into a convex shape. It should be noted that the thickness of the first paper layer 11 can also be adjusted by, for example, whether or not calendering is performed, calendering pressure, embossing process, wrinkling rate, etc. In addition, the paper thickness is expected to be further adjusted according to the roll length. It is expected that the paper thickness will be set to 100 μm~120 μm for products with a roll length of 1.5 times the roll length, 95 μm~110 μm for products with a roll length of 2 times the roll length, 70 μm~90 μm for products with a roll length of 3 times the roll length and 3.2 times the roll length, and 65 μm~75 μm for products with a roll length of 4.2 times the roll length.

[0048] The thickness of the second paper layer 12 in the toilet paper 10 of this embodiment is not necessarily limited, but it is highly desirable to set it to 65 μm to 120 μm, similar to the first paper layer 11. Furthermore, the difference in thickness between the first paper layer 11 and the second paper layer 12 is expected to be within 20 μm. There is no difference in the crushability of the protrusions in the paper thickness direction (also known as the Z direction), and the protrusions of the second paper layer 12 are unlikely to excessively affect the first paper layer 11. It should be noted that the thickness of the second paper layer 12 can also be adjusted, for example, by adjusting the presence or absence of calendering, calendering pressure, embossing process, and wrinkle rate.

[0049] Here, the method for determining the weight per unit area (basis weight) follows the provisions of JIS P 8124. Additionally, the method for determining paper thickness is as follows: After the test piece is fully conditioned (usually for about 8 hours) under the conditions of JIS P 8111 (1998), it is measured using a dial-type thickness gauge (thickness measuring instrument) "PEACOCK H type" (manufactured by Ozaki Corporation) under the same conditions. Double-layer paper thickness is measured directly in its double-layer state; the first paper layer 11 or the second paper layer 12 is measured after being peeled down to each individual layer. The specific measurement method is as follows: After confirming that there is no debris, dust, etc. between the plunger and the measuring stage, lower the plunger onto the measuring stage, move the scale of the aforementioned dial-type thickness gauge to zero, then lift the plunger and place the sample on the test stage. From the state where the plunger is opened to 700 μm, lower the rod all at once and read the scale value at this point. During measurement, only the plunger is placed without pressing it. The plunger's terminal, a circular plane with a diameter of 10 mm, abuts perpendicularly to the paper plane, and the load during paper thickness measurement is approximately 70 gf. It should be noted that the paper thickness is the average value obtained from 10 measurements.

[0050] Regarding the specific volume of the toilet paper 10 in this embodiment, both the first paper layer 11 and the second paper layer 12 are expected to have a volume of 5.5 cm³. 2 / g~7.5 cm 2 / g. Specific volume is the paper thickness divided by the weight per unit area, expressed as volume per 1 g in cm³. 3 The value represented. Furthermore, the specific volume ratio (specific volume of the first paper layer / specific volume of the second paper layer) is expected to be 90%~110%. The difference in paper quality between the first paper layer 11 and the second paper layer 12 is small, and the difference in smoothness, softness, and skin-touch feel caused by the difference in paper quality is also reduced.

[0051] On the other hand, such as Figures 2 to 7 As shown, the toilet paper 10 of this embodiment is characterized in that the embossed pattern of the first paper layer 11, at least on the outer surface of the roll, has recesses 32 arranged at predetermined intervals in a straight line, and grooves 35 that are shallower than the recesses 32 and extend in all directions from the recesses 32 and connect the recesses 32. The first paper layer 11 is located on the outer surface of the roll and is always visually identifiable in its rolled form, and constitutes the outer surface that is touched by hand; therefore, appearance, softness, and surface smoothness are particularly important. The toilet paper 10 with the embossed pattern of recesses 32 arranged at predetermined intervals in a straight line and grooves 35 extending in all directions from the recesses 32 and connecting the recesses 32 not only presents a geometrically regular appearance but also improves softness and surface smoothness. In particular, since the grooves 35 make the whole roll easily stretchable, it is suitable for improving the softness and surface smoothness of long-sized toilet paper 10. It should be noted that the grooves 35 are preferably of a certain depth or the central portion between the recesses 32 is the shallowest part.

[0052] The embossed pattern in the second paper layer 12 does not necessarily have to be the same as that in the first paper layer 11, but it is preferable that it is the same as that in the first paper layer 11, having recesses 32 arranged at predetermined intervals in a straight line, and grooves 35 that are shallower than the recesses 32 and extend in all directions from the recesses 32 and connect the recesses 32. The grooves 35 of the second paper layer 12 are also expected to have a certain depth or the central part between the recesses 32 should be the shallowest part. By using the same embossed pattern as the first paper layer 11, the difference in paper quality and skin feel between the front and back of the toilet paper 10 is reduced.

[0053] The shape of the recess 32 in this embodiment is not necessarily limited. Examples include... Figure 2 and Figure 3 The four-pointed star shape shown Figure 4 The quadrilateral shown Figure 5 The circle shown Figure 6 The shape shown is an ellipse, etc. In addition, a rounded quadrilateral, etc., can also be used. Preferably, it is an oval shape. Figure 2 , Figure 3 The four-pointed star shape shown is formed by curves or straight lines. Figure 4 The quadrilateral shown. Quadrilaterals and four-pointed stars are preferably formed where the lines connecting their vertices are orthogonal. As for the shape of the recess 32, a particularly preferred shape is... Figure 2 The recess 32 is shown as a four-pointed star formed by curves. If the shape of the recess 32 is a four-pointed star formed by curves, the non-recessed portions between the recesses 32 become rounded quadrilaterals, and the edges of the recesses 32 become curved, thus making it easy to feel smoothness and softness when touched. Alternatively, if the shape of the recess 32 is a four-pointed star or quadrilateral formed by curves or straight lines, the grooves 35 are expected to extend from the four vertices of the recess 32. The shape of the recess 32 does not necessarily have to be the same in the first paper layer 11 and the second paper layer 12, but it is desirable that the shapes of the recesses 32 in the first paper layer 11 and the second paper layer 12 are the same. This reduces the difference in paper quality and skin feel between the front and back sides of the toilet paper 10.

[0054] Here, the toilet paper 10 of this embodiment is characterized in that, in the first paper layer 11, the arrangement direction LD of the recesses 32 and the extension direction RD of the grooves 35 are not consistent with the flow direction MD of the toilet paper 10. If the arrangement direction LD of the recesses 32 and the extension direction RD of the grooves 35 are not consistent with the flow direction MD of the toilet paper 10, the crushing, collapse, and reversal of the recesses are improved. Here, the flow direction of the toilet paper 10 refers to the direction that is consistent with the winding direction and is stretched during the winding of the paper roll or after the paper roll is formed. Generally, it is the longitudinal direction of the paper (MD direction). If the arrangement direction LD of the recesses 32 and the extension direction RD of the grooves 35 are consistent with the flow direction of the toilet paper 10, it is believed that under the stretching action during the winding of the paper roll or after the paper roll is formed, due to the tension difference between the portion with recesses intermittently arranged along the flow direction and the portion without recesses, and the tension difference between the portion with extended grooves and the portion without extended grooves, wrinkles along the flow direction, also known as longitudinal wrinkles, are easily generated. Furthermore, these wrinkles are considered to be the cause of the collapse, crushing, and convexity caused by the reversal of the concave portions. When the arrangement direction LD of the concave portions 32 and the extension direction RD of the grooves 35 are not consistent with the flow direction MD of the toilet paper 10, it is difficult to generate longitudinal wrinkles, and therefore it is even more difficult for the collapse, crushing, and convexity caused by the reversal of the concave portions to form.

[0055] In particular, the angle between the arrangement direction LD of the recesses and the flow direction MD of the toilet paper is expected to be 10 to 45 degrees or -10 to -45 degrees. It should be noted that although the embossing pattern of the first paper layer 11 shown in the illustration represents an example where the angle between the arrangement direction LD of the recesses and the flow direction MD of the toilet paper is a negative angle (∠α) in the clockwise direction, it can also be a negative angle in the counterclockwise direction. If the angle between the arrangement direction LD of the recesses and the flow direction MD of the toilet paper is within the above range, it is particularly difficult to produce longitudinal wrinkles caused by stretching during or after the roll is formed, and the formation of convex portions caused by the collapse, crushing, or reversal of the recesses due to wrinkles is further improved.

[0056] For the second paper layer 12, when the embossed pattern is arranged such that the recesses 32 are spaced at predetermined intervals and thus form grooves extending in all directions from the recesses 32 and connecting the recesses, it is also desirable that the arrangement direction LD of the recesses 32 and the extension direction RD of the grooves 35 in the second paper layer 12 are not aligned with the flow direction of the toilet paper. This also makes it difficult to generate longitudinal wrinkles on the second paper layer 12. Furthermore, in the second paper layer, it is desirable that the angle between the arrangement direction LD of the recesses and the flow direction MD of the toilet paper is between 10 degrees and 45 degrees or between -10 degrees and -45 degrees.

[0057] Furthermore, in the toilet paper 10 of this embodiment, the embossed pattern of the first paper layer 11 and the embossed pattern of the second paper layer 12 are expected to satisfy the following relationship: the proportion of the number of recesses in the first paper layer 11 that overlap with the recesses in the second paper layer 12 when viewed from above is 80% or less, preferably 75% or less. That is, regarding the relationship of the embossed patterns, if it is a relationship of 100 recesses in the first paper layer 11 and 80 recesses in the second paper layer overlapping, then the proportion is 80%. In double-embossed toilet paper, which is similar to the toilet paper 10 of this embodiment, the paper layer wound on the outer surface and the paper layer wound on the inner surface are not bonded by adhesives or the like, the positions of the protrusions (recesses) of the paper layer wound on the outer surface and the protrusions (recesses) of the paper layer wound on the inner surface are generally not adjusted. Therefore, when the paper layer on the outer surface is overlapped with the paper layer on the inner surface, the following parts are randomly formed: the part where the convex (concave) part of the paper layer on the outer surface overlaps with the convex (concave) part of the paper layer on the inner surface; the part where the convex (concave) part of the paper layer on the outer surface is located in the non-formed part of the convex (concave) part of the paper layer on the inner surface; and the part where the convex (concave) part of the paper layer on the outer surface is located in the non-formed part of the convex (concave) part of the paper layer on the inner surface. The interference between the convex (concave) part of the paper layer on the outer surface and the convex (concave) part of the paper layer on the inner surface is randomly generated on the paper surface. This is considered to be one of the reasons for the crushing, collapse, and reversal of the concave part of the paper layer on the outer surface. As shown in this embodiment, when the pattern of the recess 32 of the first paper layer 11 overlaps with the pattern of the recess 32 of the second paper layer 12 on the plane, if the ratio of the number of recesses of the first paper layer 11 overlapping with the recesses of the second paper layer 12 is 80% or less, then even without adjusting the positions of the protrusions (recesses) of the paper layer wound on the outer surface and the protrusions (recesses) of the paper layer wound on the inner surface, the crushing, collapse, and reversal of the recesses of the paper layer wound on the outer surface can be further improved.

[0058] Furthermore, from the viewpoint of the amount of overlap between the recesses 32 of the first paper layer 11 and the recesses 32 of the second paper layer 12, it is preferable that the angles between the arrangement directions of the recesses of the first paper layer 11 and the arrangement directions of the recesses of the second paper layer 12 and the flow direction MD of the toilet paper 10 are in opposite directions. That is, if the arrangement direction LD of the recesses of the first paper layer 11 is as follows... Figure 2 The angle between the paper and the flow direction MD of the toilet paper is ∠α in the clockwise direction. Therefore, the desired arrangement direction LD of the concave portions of the second paper layer 12 is as follows: Figure 12The angle between the embossed pattern of the first paper layer 11 and the toilet paper flow direction MD is ∠β in the counterclockwise direction. Of course, the arrangement direction LD of the recesses in the first paper layer 11 can also be at an angle in the counterclockwise direction, and the arrangement direction LD of the recesses in the second paper layer 12 can also be at an angle in the clockwise direction. In particular, it is preferable to form the embossed pattern of the second paper layer as a linearly symmetrical pattern with respect to the embossed pattern of the first paper layer 11 about the toilet paper flow direction MD as the axis of symmetry. When such embossed patterns are formed for the first paper layer 11 and the second paper layer 12, then as... Figure 12 As shown in the toilet paper, the arrangement direction LD and groove extension direction RD of the recesses 32 in the first paper layer 11 and the arrangement direction LD and groove extension direction RD of the recesses 32 in the second paper layer 12 are not consistent with the flow direction of the toilet paper. Furthermore, without adjusting the position of the recesses 32 in the first paper layer 11 and the position of the recesses 32 in the second paper layer 12 in the flow direction MD of the toilet paper, the overlap of the recesses 32 in the first paper layer 11 and the recesses 32 in the second paper layer 12 can be 80% or less. Interference and reversal of the recesses become difficult to occur, and crushing, collapse and reversal of the recesses are further eliminated.

[0059] On the other hand, in this embodiment of toilet paper 10, it is desirable to set the height difference D1 between the deepest part of the concave portion 32 and the shallowest part of the groove 35 in the first paper layer 11 to at least 0.01 mm to 0.30 mm. More preferably, it is set to 0.01 mm to 0.25 mm, and particularly preferably, it is set to 0.01 mm to 0.20 mm. This range of height difference D1 is quite narrow. If the height difference D1 between the deepest part of the concave portion 32 and the shallowest part of the groove 35 is set to 0.01 mm to 0.30 mm, it becomes difficult to form the crushing, collapse, and convex reversal of the concave portion. In long-size double-embossed toilet paper rolls, the formation of crushed, collapsed concave portions and convex reversal of concave portions is believed to be due to: interference between the convex portions when the paper layers with concave and convex shapes are stacked together through the embossing process; stretching during paper layer transport or roll winding; and stretching after roll formation leading to concave reversal. In particular, in embossed patterns having concave portions and grooves extending outwards from the concave portions and connecting the concave portions, it is believed that when toilet paper is wound onto a roll, and in the rolled state, the concave portions are stretched along the grooves in all directions, which easily leads to the formation of convex portions due to reversal. Furthermore, in such embossed patterns having concave portions and grooves extending outwards from the concave portions and connecting the concave portions, as shown in this embodiment, by reducing the height difference between the deepest part of the concave portion 32 and the shallowest part of the groove 35 to 0.01 mm to 0.30 mm, it is difficult for reversal caused by stretching to occur. Combined with the composition of other paper materials and the roll composition, it is possible to improve the crushing and collapse of the concave portions and the formation of convex portions due to reversal.

[0060] If the embossed pattern in the second paper layer 12 also has recesses 32 and grooves 35 extending in all directions from the recesses 32 and connecting the recesses 32, then the height difference between the deepest part of the recess 32 and the shallowest part of the groove 35 is preferably 0.01 mm to 0.30 mm, the same as in the first paper layer 11. Particularly preferred is 0.05 mm to 0.28 mm, and even more particularly preferred is 0.1 mm to 0.25 mm. In the second paper layer 12, the crushing, collapse, and reversal of the recesses are also improved, and the differences in paper quality and skin feel between the front and back of the toilet paper are reduced.

[0061] To set the difference between the deepest part of the recess 32 and the shallowest part of the groove 35 within the aforementioned range, it is sufficient to set the height difference between the highest point of the convex portion forming the recess and the deepest part of the ridge portion forming the groove on the embossing roller used in the embossing process to 0.01 mm to 0.3 mm, preferably 0.05 mm to 0.2 mm or less, and particularly preferably 0.07 mm to 0.13 mm. At least, when the height difference between the highest point of the convex portion forming the recess and the deepest part of the ridge portion forming the groove on the embossing roller used in the embossing process is 0.07 mm to 0.13 mm, the difference between the deepest part of the recess and the shallowest part of the groove in the paper layer of the present invention can be set to a range of 0.01 mm to 0.30 mm.

[0062] The height difference between the deepest part of the recess 32 and the shallowest part of the groove 35 in this embodiment is measured using a single-shot 3D measuring microscope VR-3200 or similar equipment manufactured by KEYENCE Co., Ltd., and image analysis software "VR-H1A" or similar software. It should be noted that, conventionally, in double-embossed toilet paper, as described above, the measurement of depth was considered impossible or extremely difficult due to the crushing, collapse, and reversal of the recess. However, in the toilet paper roll of this embodiment, the crushing, collapse, and reversal of the recess are improved, and by further studying the measurement method, recesses that can be measured can be selected.

[0063] The measurement was conducted at a magnification of 12x and a field of view area of ​​24 mm × 18 mm. The sample used for the measurement was a section collected 10 m from the end of the roll, between the perforated lines, after removing the tail seal. This section was then separated into the first paper layer 11 and the second paper layer 12, which served as the sample. The sample size was approximately 25 mm long × 50 mm wide. The sample was placed on the measuring stage and secured in a position that would not affect the field of view, eliminating any wrinkles or undulations caused by placing it on the stage. For example, the paper layers were kept taut without excessive stretching, and a ring clamp was used for securing them.

[0064] The measurement steps are as follows: Using the aforementioned equipment and software, referencing the colors representing elevation in the image displayed from a top-down perspective, select a recess suitable for confirming its shape and elevation difference with the surrounding area. In other words, select a recess that is close to ideal, formed through embossing. Furthermore, as... Figure 8 As shown, in the image section displayed from a top-down view, the measured cross-sectional curves of line segments A1 and A2 along the direction of the valley 35 of the selected recess 32 are obtained. Using a low-pass filter, surface roughness components with wavelengths shorter than λc: 800 μm (where λc is the "filter defining the boundary between roughness components and ripple components" described in JIS-B0601 "3.1.1.2") are removed from these measured cross-sectional curves, resulting in the following... Figure 9 The corrugated curve Q1 is shown. Regarding the corrugated curves in A1 and A2, calculate the difference between the average value of the shallowest parts S1 and S2 of the two valleys 35 and the deepest part G1, and use their average value as the height difference between the deepest part of the concave section 32 and the shallowest part of the valley 35. It should be noted that the positions of the shallowest parts S1 and S2 and the deepest part G1 of the valleys 35 on the corrugated curve Q1 are determined visually by referring to the curve shape, the image of the concave section shown from a top-down view, and line segments A1 and A2. Perform the above measurements on the three embossed patterns, and use their average value as the final height difference.

[0065] Furthermore, the depth of the deepest part of the recess 32 in the first paper layer 11 is expected to be 0.02 mm to 0.5 mm. Preferably, it is 0.03 mm to 0.3 mm, and particularly preferably, it is 0.04 mm to 0.14 mm. If it is 0.02 mm to 0.5 mm, while ensuring good appearance, it is more difficult for the recess to collapse, crush, or for convex parts caused by inversion to form.

[0066] The depth of the deepest part of the recess 32 in the second paper layer 12 is also the same as that in the first paper layer 11, and is preferably 0.02 mm to 0.5 mm. Preferably, it is 0.03 mm to 0.3 mm, and particularly preferably 0.04 mm to 0.14 mm. In the second paper layer 12, regardless of the shape of the recess 32 or the presence or absence of the groove 35, it is particularly desirable to set the depth of the deepest part of the recess 32 within the above-mentioned range. Regarding the recess 32 formed on the second paper layer 12, the convex portion corresponding to this recess 32 faces the convex portion of the first paper layer 11. Therefore, the convex portion corresponding to the recess of the second paper layer 12 pressing against the convex portion corresponding to the recess of the first paper layer 11 can sometimes cause the recess of the first paper layer 11 to reverse or collapse. By setting the depth of the recess 32 of the second paper layer 12 also within the above-mentioned range, it becomes less likely to interfere with the convex portion corresponding to the recess of the first paper layer 11. This effect is particularly pronounced under the conditions of the unit area weight of the paper layer, paper thickness and other paper quality, and the winding density described later.

[0067] Here, in order to set the depth of the deepest part of the recess 32 within the aforementioned range, the height of the highest part of the protrusion formed on the embossing roller used in the embossing process for forming the recess is set to 0.05 mm to 1.3 mm, preferably 0.3 mm to 1.0 mm, and particularly preferably 0.5 mm to 0.9 mm. At least in the paper layer of the present invention, when the height of the highest part of the protrusion formed on the embossing roller used in the embossing process for forming the recess is 0.05 mm to 1.3 mm, this can be taken as the range of the depth of the deepest part.

[0068] In this embodiment, the depth D2 of the deepest part of the recess 32 and the height difference D1 between the deepest part of the recess 32 and the shallowest part of the groove 35 are measured using a single-shot 3D measuring microscope VR-3200 or similar equipment manufactured by KEYENCE Co., Ltd., and image analysis software "VR-H1A" or similar software. The measurement steps, sample collection, sample placement, and measurement method are the same as the height difference D1 between the deepest part of the recess 32 and the shallowest part of the groove 35. However, as Figure 8 As shown, the measurement locations are the non-concave portions 34, 32, and 34 beyond the valley 35, and the measurement cross-sectional curves of lines B1 and B2 at these locations are obtained. Then, through the same processing as the elevation difference D1 between the deepest part of the concave portion 32 and the shallowest part of the valley 35, the following is obtained: Figure 10 The corrugated curve Q2 is shown. Regarding the corrugated curves in B1 and B2 respectively, calculate the difference between the average value of the boundary positions P1 and P2 of the two non-concave portions 34 and 32 and the deepest point G2, and take their average value as the depth D2 of the deepest part of 32. It should be noted that the positions of the boundary positions P1 and P2 of the non-concave portions 34 and 32, and the position of the deepest point G1 on the corrugated curve Q2, are determined visually by referring to the curve shape, the image of the concave portion shown from a top-down view, and line segments B1 and B2. Perform the above measurements on the three embossed patterns, and take their average value as the final height difference.

[0069] On the other hand, the width L4 of the recess 32 in the first paper layer 11 is expected to be 1.15 mm to 1.31 mm. The width L4 of the recess 32 can be found in quadrilaterals, rounded quadrilaterals, and four-pointed stars, such as... Figure 3 The figures shown represent the distance between opposite edges; for a circle, it is the diameter; for an ellipse, it is the major and minor axes. If the width is 1.15 mm to 1.31 mm, the portion of the recess 32 that is reversed is reduced while maintaining a good appearance.

[0070] The width of the recess 32 in the second paper layer 12 is the same as that in the first paper layer, ideally between 1.15 mm and 1.31 mm. Furthermore, the area of ​​the recess is also expected to be within the same range as that in the first paper layer 11. In the second paper layer 12, crushing, collapse, and reversal of the recesses are prevented, thus reducing the difference in paper quality and skin feel between the front and back of the toilet paper.

[0071] To set the width L4 of the recess to the above range, simply set the width of the protrusion formed on the embossing roller used in the embossing process to approximately 1.15 mm to 1.31 mm, and adjust the clamping pressure during the embossing process.

[0072] The width of the recess 32 in this embodiment was also measured using a single-shot 3D measuring microscope VR-3200 or similar equipment manufactured by KEYENCE Co., Ltd., and image analysis software "VR-H1A" or similar software. The measurement steps, sample collection, sample placement, and the height difference between the deepest part of the recess 32 and the shallowest part of the valley 35 were the same. Regarding the width of the recess, the edges of the recess were visually confirmed by referring to the colors indicating height in the image displayed from a top-view perspective, and the distance between the edges was measured. At this time, the measurement cross-sectional curve and ripple curve of the line crossing the edges can be referred to.

[0073] Furthermore, in the first paper layer 11, the spacing (pitch) L5 between recesses 32 is expected to be 5.05 mm to 5.35 mm. This spacing L5 refers to the distance between adjacent recesses 32 that are not connected by the groove 35, i.e., the spacing in the straight line arrangement direction of the recesses 32 in this embodiment. If the spacing L5 between recesses 32 is 5.05 mm to 5.35 mm, it is more difficult for the recesses to be crushed, collapsed, or for convex portions to form due to the reversal of the recesses. Additionally, the shape difference between recesses and non-recesses can be clearly visually identified, resulting in excellent appearance.

[0074] The spacing (pitch) between the recesses in the second paper layer is the same as that in the first paper layer 11, and is expected to be 5.05 mm to 5.35 mm. In the second paper layer, the collapse, crushing, and reversal of the recesses are also prevented, and the differences in paper quality and skin feel between the front and back of the toilet paper 10 are reduced.

[0075] Regarding the interval L5 (spacing) between the recesses 32, simply set the interval (spacing) between the protrusions formed on the embossing roller used to form the recesses to approximately 5.05 mm to 5.35 mm, and adjust the clamping pressure during the embossing process.

[0076] The distance L5 between the recesses 32 in this embodiment can also be measured using a single-shot 3D measuring microscope VR-3200 or similar equipment manufactured by KEYENCE Co., Ltd., and image analysis software "VR-H1A" or similar software. The measurement steps, sample collection, sample placement, and height difference between the deepest part of the recess 32 and the shallowest part of the valley 35 are the same. Regarding the distance L5 between the recesses 32, the edges of the recesses are visually confirmed by referring to the colors indicating height in the image displayed from a top-view perspective, and the distance is measured. At this time, the measurement cross-sectional curve and ripple curve of the line spanning the edges of the two recesses can be referred to.

[0077] In this embodiment, the area of ​​the recesses 32 and the embossing area ratio (total area of ​​recesses / total area of ​​paper layers) in the toilet paper 10 are not necessarily limited, but the area of ​​the recesses 32 in the first paper layer 11 and the second paper layer is preferably 0.5 mm. 2 ~8 mm 2 1.0 mm is particularly preferred. 2 ~3.2 mm 2 In addition, the embossed area ratio is preferably 15% to 28%, and particularly preferably 8% to 14%.

[0078] The area and embossing area ratio of the recess 32 in this embodiment were also measured using a single-shot 3D measuring microscope VR-3200 or similar equipment manufactured by KEYENCE Co., Ltd., and image analysis software "VR-H1A" or similar software. The embossing area ratio was calculated based on the area of ​​the recess and the number of recesses in a 10 cm area along the flow direction. Regarding the area measurement, similar to the width of the recess 32, the edges of the recess were visually confirmed by referring to the colors indicating height in the image displayed from a top-view perspective, and the area of ​​the recess was calculated. At this time, the height contour of the line spanning the edges can be referenced.

[0079] On the other hand, the winding density of the toilet paper roll in this embodiment is 0.75 to 1.6. Products within this winding density range, based on the relationship between the degree of compaction of the toilet paper during or after winding and the weight per unit area and the embossing pattern, can reduce crushing, collapse, and reversal of the concave portions caused by the embossing process. It should be noted that the winding density is calculated by (paper thickness × roll length × number of layers) ÷ (cross-sectional area of ​​the roll). Furthermore, the cross-sectional area of ​​the roll is calculated by {cross-sectional area of ​​the roll diameter (outer diameter) L1 portion} - (cross-sectional area of ​​the paper tube outer diameter L3 portion).

[0080] On the other hand, the tensile strength of the toilet paper in this embodiment is not necessarily limited, but the longitudinal drying tensile strength is preferably 250 cN / 25 mm or more and 360 cN / 25 mm or less, and the transverse drying tensile strength is preferably 65 cN / 25 mm or more and 120 cN / 25 mm or less.

[0081] If the dry tensile strength is such, it is difficult for the convex part to collapse, crush, or reverse, thus achieving the required strength and toughness during use.

[0082] The dry tensile strength was determined based on JIS P 8113 (2006) and was measured as follows. Test pieces cut to approximately 25 mm (± 0.5 mm) wide and 150 mm long were used in both the longitudinal and transverse directions. The test pieces were measured directly in multiple layers. The testing machine used was the Minebea TG-200N tensile testing machine with a force sensor, manufactured by Minebea Corporation, or similar equipment. The clamp spacing was set to 100 mm, and the tensile speed was set to 100 mm / min for longitudinal measurements and 50 mm / min for transverse measurements. The measurement was performed as follows: the two ends of the test piece were secured to the clamps of the testing machine, a tensile load was applied to the paper in the vertical direction, and the reading at the point of paper breakage (digital value) was recorded. Five sets of samples were prepared for both the longitudinal and transverse directions, and five measurements were performed in each direction. The average value of these measurements was taken as the dry tensile strength in each direction.

[0083] On the other hand, the toilet paper 10 of this embodiment may contain known dry strength agents, dry strength agents, and temporary wet strength agents, but these paper strength agents may reduce softness and hydrolysis, so it is preferable not to add these paper strength agents. Therefore, the toilet paper of this embodiment is preferably free of at least one of dry strength agents, dry strength agents, and temporary wet strength agents, more preferably free of two of them, and particularly preferably free of all of them.

[0084] Furthermore, the toilet paper 10 of this embodiment preferably contains a softener. Examples of softeners include fatty acid ester softeners and cationic fatty acid amide softeners. The fatty acid ester softener can be any one of cationic fatty acid ester compounds or nonionic fatty acid ester compounds, and multiple types can be added. Alternatively, examples of cationic fatty acid amide softeners include reactants obtained by reacting amide compounds obtained from the reaction of polyalkylene polyamines with monocarboxylic acids and epoxy halides. The content of the softener is not necessarily limited, but it is desirable to contain 0.5 to 4.0 kg / t of pulp.

[0085] Here, in the toilet paper roll 1 of this embodiment, the TS750 value of the outer surface of the first paper layer 11, measured using a paper softness measuring device (TSA), is preferably 12.0 dBV for products with a roll length of 37.5 m to 60 m.2 For products with rms of 75 m to 125 m and below, 13.0 dBV is preferred. 2 RMS and below.

[0086] The paper softness measuring device TSA in this embodiment is a paper softness measuring device TSA and similar equipment manufactured by Emtec Electronic GmbH (Japan agent: Rufuto Co., Ltd.) of Germany. The TS750 in this embodiment is the value measured by the paper softness measuring device TSA manufactured by Emtec. TS750 refers to the intensity of the first maximum peak in the spectrum observed from the low-frequency side when a sample placed on a sample stage is pressed in from above with a pressure of 100 mN and rotated at a speed of 2.0 revolutions per second, and the vibration of the sample stage is measured by a vibration sensor. This is a parameter affected by "smoothness / roughness". It should be noted that in the measurement of the paper softness measuring device TSA in this embodiment, the sample is processed into a circle with a diameter of approximately 112.8 mm using an Emtec sample cutter, and the software for analysis and numerical conversion uses the Emtec Measurement System.

[0087] Furthermore, the softness of the toilet paper 10 in this embodiment is preferably 3.0 cN / 100 mm or less, and particularly preferably 2.8 cN / 100 mm to 1.0 cN / 100 mm. This softness is determined based on the Handle-O-Meter method according to JIS L 1096 (2010) E method. As long as the softness is within the above range, it is sufficient in terms of surface properties and softness.

[0088] The pulp fibers in the toilet paper 10 of this embodiment are not particularly limited, but preferably 70% to 100% by mass of virgin pulp and 0% to 30% by mass of waste paper pulp. If waste paper pulp is blended, it can be manufactured at a lower cost compared to the case consisting of 100% by mass of virgin pulp. Furthermore, waste paper pulp tends to have finer fibers compared to the unrecycled pulp fibers during the process of recycling waste paper. Based on this fiber property, the fibers can be made denser without increasing the paper thickness, but due to the finer fibers, it is difficult to exhibit paper strength. If excessive blending is performed, the softness, smoothness, and other hand feel will decrease. Therefore, considering the characteristics of waste paper pulp, its blending ratio should preferably be determined within the range of 0% to 30% by mass. However, from the perspective of paper strength and quality, 100% virgin pulp is particularly preferred. In this case, the virgin pulp is preferably softwood kraft pulp (NBKP) and hardwood kraft pulp (LBKP). Regarding their blending ratio, it is desirable to set NBKP : LBKP at 20 : 80 to 50 : 50. It should be noted that the types of waste paper pulps used for blending are not necessarily limited, but waste paper pulps made from milk carton waste paper and high-quality waste paper are particularly preferred. These pulps, due to the large-scale blending of softwood kraft pulp (NBKP) and hardwood kraft pulp (LBKP) from the raw material sources, tend to exhibit high paper strength.

[0089] Example

[0090] Next, examples and comparative examples of the sanitary toilet paper of the present invention were prepared, and physical properties were measured and sensory evaluations were performed regarding the crushing of the recesses, etc.

[0091] It should be noted that the toilet paper in the embodiments and comparative examples is double-layered and double-embossed, that is, concave portions and corresponding convex portions are formed on the paper layers located on the outer surface side and the inner surface side of the winding through embossing, and the layers are stacked with the convex portion forming surfaces facing each other. In addition, both the embodiments and comparative examples use 100% virgin pulp paper.

[0092] The roll length of Example 1, Example 1C and Comparative Example 1 was 45 m, which was set to be about 1.5 times the roll length of conventional products.

[0093] The roll length of Examples 2, 2C and Comparative Example 2 was 60 m, which was set to be about twice the roll length of the conventional product.

[0094] The roll length of Examples 3, 3C and Comparative Example 3 was 80 m, which was about 3 times the roll length of the conventional product.

[0095] The roll length of Example 4, Example 4C and Comparative Example 4 was 106 m, which was set to be about 4.2 times the roll length of the conventional product.

[0096] The embossed patterns on the first paper layer of Examples 1, 2, 3, and 4 are Figure 2 The pattern shown has a four-pointed star-shaped recess, and the angle between the recess arrangement direction LD and the flow direction MD is -30 degrees. The embossed pattern on the second paper layer is... Figure 11 The pattern shown has a four-pointed star-shaped recess, and the angle between the recess arrangement direction LD and the flow direction MD is 30 degrees. Furthermore, in the embossed patterns of the first paper layer in Examples 1, 2, 3, and 4, the arrangement direction of the recesses and the extension direction of the aforementioned grooves are inconsistent with the flow direction of the toilet paper.

[0097] The embossed patterns on the first paper layer of Examples 1C, 2C, 3C, and 4C are Figure 2 The pattern shown has a four-pointed star-shaped recess, and the angle between the recess arrangement direction LD and the flow direction MD is -30 degrees. The embossed pattern on the second paper layer is... Figure 12 The patterns shown have square-shaped recesses and four-pointed star-shaped recesses. The angle between the arrangement direction LD of the recesses and the flow direction MD is 60 degrees. Furthermore, in the embossed patterns of the first paper layer in Examples 1C, 2C, 3C, and 4C, the arrangement direction of the recesses and the extension direction of the aforementioned grooves are inconsistent with the flow direction of the toilet paper.

[0098] The toilet paper in Comparative Examples 1 to 4 is Figure 13 The embossed pattern shown has four-pointed star-shaped recesses on both the outer and inner surfaces of the paper layer (first paper layer in the table). The arrangement of these recesses aligns with the flow direction of the toilet paper (the angle corresponding to ∠α and ∠β is 0 degrees). Furthermore, the arrangement of these recesses on both the outer and inner surfaces is also designed to be consistent.

[0099] Furthermore, no dry strength agent, wet strength agent, or temporary wet strength agent was added to the base paper of the toilet paper in the examples and comparative examples. The softener was used in the same proportions in both examples and comparative examples.

[0100] Sensory evaluation of indentations, such as crushing, was conducted by visually inspecting an arbitrary area of ​​25 mm x 50 mm, starting 10 m from the outside of the roll of paper. The evaluation focused on the condition of the indentations and the degree of longitudinal wrinkling within this area. Five subjects participated, and scores were calculated by rounding the average to 0.5. The scoring criteria were as follows: For "indentation crushing, collapse, and reversal," 1 point was awarded for "indentation, collapse, and reversal observed in all indentations," 2 points for "indentation, collapse, and reversal observed in almost all indentations," 3 points for "indentation, collapse, and reversal observed in indentations," and 4 points for "no indentation crushing, collapse, or reversal observed." For "longitudinal wrinkling," 1 point was awarded for "longitudinal wrinkling observed along the entire width of the roll," 2 points for "three or more longitudinal wrinkles identifiable, though not along the entire width," 3 points for "one or two longitudinal wrinkles identifiable," and 4 points for "no longitudinal wrinkles identified."

[0101] [Table 1]

[0102] As shown in Table 1, comparisons were made between Examples 1, 1C and Comparative Examples 1, 2, 2A and Comparative Examples 2, 3, 3A and Comparative Examples 3, 4, 4A and Comparative Examples 4, all with the same roll length. The TS750 values ​​of each example were superior to those of the comparative examples. This indicates that the examples were evaluated as superior in terms of surface smoothness.

[0103] Furthermore, in the sensory evaluation test, for the comparative examples, Comparative Examples 2 to 4, with a roll length of 2 times or more, the evaluation was "crushing, collapse, and reversal were observed in all recesses"; while for the examples, even in products with a roll length equivalent to 4 times the roll length, the evaluation was "no crushing, collapse, or reversal was observed in the recesses". It should be noted that regarding the depth of the recesses in the table, for portions that could not be measured due to crushing, collapse, or reversal of the recesses, the design value is recorded.

[0104] Based on the above results, in the sanitary paper of the present invention, the crushing, collapse, and formation of the concave portion turning into a convex portion of the concave portion are improved, and the smoothness and fluffiness are enhanced.

[0105] Figure Labels

[0106] 1… Toilet paper roll, 10… Toilet paper, 11… First paper layer, 12… Second paper layer, 20… Paper tube (core), 31… Protrusion, 32… Recess, 34… Non-recess, 35… Groove, L1… Roll diameter of toilet paper roll, L2… Width of toilet paper roll, L3… Core diameter of toilet paper roll, L4… Width of recess, L5… Spacing between recesses, LD… Arrangement direction of recesses, RD… Extension direction of groove, MD… Flow direction of toilet paper, ∠α… Angle between the arrangement direction of recesses in the first paper layer and the flow direction of toilet paper, ∠β… Angle between the arrangement direction of recesses in the second paper layer and the flow direction of toilet paper, 110… Comparative toilet paper, 111… Paper layer wound around the outer surface of the comparative example, 112… Paper layer wound around the inner surface of the comparative example, 132… Recess of the comparative example, 135… Groove of the comparative example.

Claims

1. A toilet paper roll, comprising a double-layered, double-embossed toilet paper roll formed by stacking a first paper layer and a second paper layer with their convex surfaces facing each other, wound onto a paper tube, wherein, The first paper layer has a recess formed by embossing and a corresponding protrusion located on the outer surface side of the winding; the second paper layer has a recess formed by embossing and a corresponding protrusion located on the inner surface side of the winding. The toilet paper roll is characterized in that... The toilet paper roll has a roll length of 45 m or more, a roll diameter of 110 mm to 130 mm, and a winding density of 0.75 to 1.

6. The toilet paper has a unit area weight of 11.0 g / m² per layer. 2 ~18.0 g / m 2 The thickness of the double-layer paper is 125 μm to 205 μm, and the thickness of the first paper layer is 65 μm to 120 μm; and At least the first paper layer has an embossed pattern having recesses arranged at predetermined intervals in a straight line, and grooves shallower than the recesses that extend in all directions from the recesses and connect the recesses, and the arrangement direction of the recesses and the extension direction of the grooves are not consistent with the flow direction of the toilet paper.

2. The toilet paper roll according to claim 1, wherein, The angle between the direction of the recesses and the direction of toilet paper flow is 10 to 45 degrees or -10 to -45 degrees.

3. The toilet paper roll according to claim 1 or 2, wherein, The concave portion of the first paper layer is quadrilateral or four-pointed star shaped, and the grooves extend from the four vertices of the concave portion.

4. The toilet paper roll according to claim 3, wherein, The spacing between the recesses in the first paper layer is 5.05 mm to 5.35 mm.

5. The toilet paper roll according to claim 3 or 4, wherein, The width of the recess in the first paper layer is 1.15 mm to 1.31 mm.

Images