Paper towel roll

Abstract

The objective is to provide a paper towel roll that, even when made by laminating multiple plies of highly absorbent sheets, does not experience ply separation, does not feel slimy due to ply bond glue leaching, and does not develop wrinkles. [Solution] In a paper towel roll in which paper towels laminated in 2-ply or 3-ply form are wound into a roll shape, the paper towel has an embossed pattern due to ply embossing, and the basis weight is 30.0 g / m² per product ply. 2 More than 56.0g / m 2 The following is the water absorption capacity: 310g / m² per product ply. 2 More than 580g / m 2 The above problem is solved by a paper towel roll characterized by the following, and by not using plybond glue in the lamination.

Description

[Technical Field]

[0001] This invention relates to a paper towel roll manufactured using a ply embossing process. [Background technology]

[0002] In recent years, various types of paper towels, including sheet-shaped paper towels and paper towel rolls made by winding these paper towels into a roll, have been developed and sold. Paper towels are required to be soft and absorbent, and for example, Patent Document 1 discloses that absorbent towel paper webs produced using TAD (through-air drying) papermaking technology have irregularities derived from the papermaking process, resulting in increased bulkiness and superior absorbency.

[0003] Furthermore, Patent Document 2 discloses that a kitchen towel sheet made by bonding sheets with an embossed pattern with adhesive and laminating them into two plies has an uneven pattern derived from the papermaking process, and by specifying the basis weight, paper thickness, water absorption, roll length, and roll diameter, it has good water absorption, is not bulky, does not peel off the plies, and requires less frequent replacement.

[0004] However, because paper towels produced using TAD papermaking technology have excellent water absorption, when laminated with multiple plies, the adhesive bonding the plies together (hereinafter also called "ply bond glue") dissolves when a lot of moisture is absorbed, making the plies prone to peeling. Therefore, while increasing the amount of ply bond glue can suppress ply peeling, it also causes the ply bond glue to dissolve in water, resulting in a slimy and unpleasant feel when using the paper towels.

[0005] Therefore, when attempting to bond the plies using single embossing with steel and rubber rolls, a method widely used for toilet paper, the paper towels produced by TAD papermaking technology were too thick to achieve adequate adhesion. Furthermore, increasing the depth of the embossing (making the difference in embossing depth larger) to firmly bond the plies resulted in the paper becoming prone to wrinkling.

[0006] Therefore, in the paper towel obtained by the TAD papermaking technique, it has been an issue to achieve both eliminating the peeling of the ply during use and the slimy feeling caused by the elution of the ply bond glue.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0008] The present invention has been made in view of such circumstances, and an object thereof is to provide a paper towel roll in which a plurality of plies of sheets with high water absorption are laminated, and there is no ply peeling, no slimy feeling due to the elution of ply bond glue, and no occurrence of wrinkles.

Means for Solving the Problems

[0009] The inventor conducted intensive studies and found that, in a paper towel roll obtained by winding a paper towel laminated in two or three plies in a roll shape, by defining the embossing method, basis weight, water absorption amount, and the adhesion method of the laminated plies of the paper towel, the above problems can be solved, and the present invention has been completed.

[0010] (1) The first aspect of the present invention is a paper towel roll obtained by winding a paper towel laminated in two or three plies in a roll shape, wherein the paper towel has an embossing pattern by ply embossing, the basis weight is 30.0 g / m per product ply 2 or more and 56.0 g / m 2 or less, and the water absorption amount is 310 g / m per product ply 2 or more and 580 g / m 2The following is a paper towel roll characterized in that no plybond glue is used in the lamination.

[0011] (2) A second aspect of the present invention is a paper towel roll as described in (1), characterized in that the depth of the embossed pattern is 0.05 mm or more and 0.60 mm or less.

[0012] (3) A third aspect of the present invention is a paper towel roll according to (1) or (2), characterized in that the width of the embossed pattern is 2 mm or more and 42 mm or less.

[0013] (4) A fourth aspect of the present invention is a paper towel roll according to (1) or (2), characterized in that the water absorption capacity of the paper towel is 7.0 g / g or more and 14.0 g / g or less per product ply.

[0014] (5) A fifth aspect of the present invention is a paper towel roll according to (1) or (2), characterized in that the paper towel contains 60% by mass or more of wet pulp.

[0015] (6) A sixth aspect of the present invention is a paper towel roll according to (1) or (2), characterized in that the paper thickness of the paper towel is 0.42 mm or more and 0.86 mm or less per product ply.

[0016] (7) A seventh aspect of the present invention is a paper towel roll according to (1) or (2), characterized in that when the paper thickness per product ply of the paper towel is A and the depth of the embossed pattern is B, the value of (B ÷ A × 100) is 7 or more and 90 or less.

[0017] (8) An eighth aspect of the present invention is a paper towel roll according to (1) or (2), characterized in that the paper towel has an uneven surface derived from the TAD papermaking process. [Effects of the Invention]

[0018] According to the present invention, even in a paper towel roll made by laminating multiple plies of highly absorbent sheets, it is possible to provide a paper towel roll that does not experience ply peeling, does not become slimy due to the elution of ply bond glue, and does not develop wrinkles. [Brief explanation of the drawing]

[0019] [Figure 1] This is a perspective view of a paper towel roll according to one embodiment of the present invention. [Figure 2] This figure shows an example of an embossed pattern created by ply embossing. [Figure 3] This diagram shows the height profile on the XY plane as measured by a microscope, using a photograph (shading). [Figure 4] This figure shows the height profile on the XY plane as measured by a microscope. [Figure 5] This diagram shows how to determine the depth of an embossing from a graph of the height profile on the XY plane obtained using a microscope. [Figure 6] This figure shows an example of the measurement position when measuring the depth of a ply embossed surface. [Figure 7] This figure shows a method for measuring the water absorption capacity of a paper towel sheet according to the present invention. [Figure 8] This figure shows a part of the TAD papermaking process for the paper towel sheet of the present invention. [Modes for carrying out the invention]

[0020] The following describes in detail embodiments for carrying out the present invention (hereinafter simply referred to as "this embodiment"). The following embodiments are illustrative for explaining the present invention and are not intended to limit the present invention to the following content. The present invention can be implemented by modifying it as appropriate within the scope of its gist.

[0021] In this specification, "product ply" refers to the number of plies in a paper towel in its product state, without separating the laminated sheets into individual sheets.

[0022] In this specification, "paper towel roll" (hereinafter also simply referred to as "roll") means a roll product in which paper towels are wound into a roll shape.

[0023] "MD direction" refers to the direction in which the material flows through the machine, and "CD direction" refers to the direction perpendicular to the MD direction. In this specification, "MD direction of the roll" refers to the direction in which the paper towel is wound (Y direction in Figure 1), and "CD direction of the roll" refers to the direction perpendicular to the direction in which the paper towel is wound (X direction in Figure 1).

[0024] <Paper towel roll> An embodiment of the paper towel roll 1 (hereinafter also simply referred to as "roll 1") according to the present invention will be described with reference to Figure 1. Figure 1 is a perspective view of roll 1. As shown in Figure 1, a roll is formed by winding a paper towel 1x laminated in 2-ply or 3-ply layers.

[0025] As shown in Figure 2, the paper towel 1x has an embossed pattern created by ply embossing. Also, as shown in Figure 1, the front sheet 1a facing outwards from the roll 1 and the back sheet 1b facing towards the center of the roll are laminated in two plies. The end of the paper towel 1x is referred to as the outermost edge 1e of the roll 1.

[0026] Preferably, the roll 1 has perforations 1c in the roll width direction at approximately equal intervals in the roll winding direction.

[0027] Uses of Roll 1 include, for example, rolls of kitchen paper (sometimes called paper towels or cooking paper) used in home kitchens or restaurant kitchens for wiping up moisture or oil and removing dirt, hand towels, wipers, and other rolls of sanitary paper.

[0028] The present invention will be described below in three parts: [1] paper towels, [2] paper towel rolls, and [3] a method for manufacturing paper towel rolls.

[0029] [1] Paper towels Paper towel 1x is a sheet-like material that has been laminated in 2-ply or 3-ply layers through a papermaking process without using plybond glue, and then embossed using ply embossing. In this invention, "without using plybond glue" means that not only adhesive components but also water for bonding purposes is not used.

[0030] (Paper making method) It is preferable to use a sheet obtained by TAD (Through-Air Drying) papermaking technology for paper towel 1x. TAD papermaking technology is a technique in which air drying is performed during the dewatering and drying process of the papermaking process (it is preferable not to press-dewater the wet paper), and by manufacturing with TAD papermaking technology, the paper towel 1x can have irregularities derived from the TAD papermaking process, resulting in a bulky, soft paper towel 1x with excellent water absorption.

[0031] (raw materials) Paper towel 1x may contain pulp fibers. The pulp fibers preferably consist of wood pulp containing at least one of NBKP (bleached softwood kraft pulp fibers) and LBKP (bleached hardwood kraft pulp fibers), namely BKP. The BKP content is preferably 70% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more, and most preferably 100% by mass. The mass ratio of NBKP to LBKP (NBKP:LBKP) is preferably 40-90% by mass:10-60% by mass. By setting the mass ratio of NBKP to LBKP within the above range, the fiber length contained in the pulp becomes appropriate, and the occurrence of wrinkles can be suppressed. The mass ratio of NBKP to LBKP (NBKP:LBKP) is more preferably 50-80% by mass:20-50% by mass, and even more preferably 60-70% by mass:30-40% by mass.

[0032] (Wet pulp content) The proportion of wet pulp fibers in paper towel 1x (hereinafter also referred to as "wet pulp content") is preferably 60% by mass or more per product ply, more preferably 70% by mass or more, and even more preferably 85% by mass or more. If the wet pulp content is less than 60% by mass, the water absorption will be poor when the basis weight of paper towel 1x is low. Paper towel 1x manufactured with wet pulp is easier to increase in strength compared to paper towels manufactured with only dry pulp, thus suppressing wrinkle formation and further improving water absorption.

[0033] Wet pulp refers to wet pulp (sheets) or slush pulp, and is pulp with a solid content of 60% by mass or less, preferably 1% to 50% by mass, more preferably 2% to 20% by mass, and even more preferably 3% to 10% by mass. Dry pulp (sheets) has a solid content of approximately 90% by mass.

[0034] (Irregularities resulting from the TAD papermaking process) It is preferable that the paper towel 1x has irregularities derived from the TAD papermaking process. If it does not have irregularities derived from the TAD papermaking process, the water absorption of the paper towel 1x will be inferior.

[0035] (Embossed) It is preferable that the paper towel 1x has an embossing other than the "ply embossing" described later (not shown). The embossing may be single embossing, double embossing, or matched steel embossing, but double embossing is more preferable. Also, the embossing may be applied only to the front sheet 1a.

[0036] Double embossing involves embossing two or more sheets of 1x paper towel (1a and 1b) and then laminating the sheets so that the convex sides of the embossing face each other. Double embossing makes it easier to increase the paper thickness and specific volume, and thus improves water absorption. When double embossing, it is possible to increase the number of plies by two or more using edge embossing or adhesive, but using adhesive is preferable because it makes it easier to maintain the shape of the embossing. Furthermore, nested embossing is preferred as a double embossing method.

[0037] (Number of plies) The number of plies in a paper towel roll is between 2 and 3. If the number of plies is less than 2, the absorbency of the roll will be poor, and if it exceeds 3 plies, the basis weight per ply will decrease within a certain range, making the plies more prone to peeling. A ply count of 2 is preferable.

[0038] (Paper thickness per 10 plies) The paper thickness per 10 plies of a 1x paper towel (hereinafter also simply referred to as "paper thickness (10 plies)") is preferably 2.1 mm or more at the lower limit, more preferably 2.4 mm or more, and even more preferably 2.7 mm or more. The paper thickness is preferably 4.3 mm or less, more preferably 3.8 mm or less, and even more preferably 3.6 mm or less at the upper limit. If the paper thickness (10 plies) is less than 2.1 mm, the water absorption will be poor and the plies will be more prone to peeling. If the paper thickness (10 plies) exceeds 4.3 mm, the 1x paper towel will be more prone to wrinkling.

[0039] (Paper thickness per product ply) The paper thickness per product ply of a 1x paper towel (hereinafter also simply referred to as "paper thickness (product ply)") is preferably 0.42 mm or more and 0.86 mm or less. If the paper thickness (product ply) is less than 0.42 mm, the water absorption will be poor and ply peeling will be more likely to occur. If the paper thickness (product ply) exceeds 0.86 mm, the 1x paper towel will be more prone to wrinkling. The lower limit of the paper thickness (product ply) is more preferably 0.48 mm or more, and even more preferably 0.54 mm or more. The upper limit is more preferably 0.76 mm or less, and even more preferably 0.72 mm or less.

[0040] The paper thickness shall be the value measured by the following method. The device used shall be a thickness gauge (Dial Thickness Gauge "PEACOCK" manufactured by Ozaki Seisakusho Co., Ltd.). (1) The measurement conditions are a measuring load of 3.7 kPa and a probe diameter of 30 mm. The sample is placed between the probe and the measuring stand, and the gauge is read when the probe is lowered at a speed of 1 mm or less per second. (2) The paper thickness will be measured at 10 points in total: 5 points in the MD direction of the sheet that are different from each other, and 5 points that are shifted in the CD direction from these 5 points. It is important to measure the paper thickness at 10 different points, but the exact positions are not required. (3) When measuring paper thickness (10 plies), stack 10 plies (5 sets of 2-ply sheets) and measure, repeating the measurement 10 times and averaging the results. If it is a 3-ply sheet, stack 9 plies (3 sets of 3-ply sheets) and measure, and calculate the paper thickness of one ply from the measurement results and convert it to 10 plies. (4) Paper thickness (product ply) is calculated by converting the paper thickness per 10 plies into the number of product plies.

[0041] (Basic weight) The basis weight per ply of a 1x paper towel (hereinafter also simply referred to as "basis weight (ply)") is 30.0 g / m². 2 More than 56.0g / m 2 The following applies: Basis weight (product ply) is 30.0 g / m². 2If it is less than this value, the water absorbency will be poor and peeling will easily occur. When the basis weight (product price) is more than 56.0 g / m 2 the paper towel 1x will easily wrinkle. The lower limit value of the basis weight (product price) is preferably 34.0 g / m 2 or more, and more preferably 38.0 g / m 2 or more. The upper limit value is preferably 50.0 g / m 2 or less, and more preferably 46.0 g / m 2 or less. Note that the basis weight is measured based on JIS P 8124.

[0042] (Specific volume) The specific volume per product price of the paper towel 1x (hereinafter also simply referred to as "specific volume (product price)") has a lower limit value of preferably 11.0 cm 3 / g or more, more preferably 12.0 cm 3 / g or more, and still more preferably 13.0 cm 3 / g or more. The upper limit value is preferably 18.0 cm 3 / g or less, more preferably 17.0 cm 3 / g or less, and still more preferably 16.0 cm 3 / g or less. When the specific volume (product price) is less than 11.0 cm 3 / g, the water absorbency is poor, and when it exceeds 18.0 cm 3 / g, the paper towel 1x will easily wrinkle.

[0043] The specific volume (product price) is represented by dividing the paper thickness (product price) by the basis weight (product price) and expressing the volume per unit g in cm 3 units.

[0044] (Price embossing) Paper towel 1x is made by laminating the base paper into 2-ply or 3-ply layers without using ply bond glue, and then applying an embossed pattern using ply embossing (also known as "knurling" or "edge embossing"). By employing this ply embossing method, the same embossed pattern can be formed on multiple plies simultaneously. Furthermore, the pressing force during embossing can bond multiple plies together, eliminating the need for ply bond glue.

[0045] Ply embossing (processing) is preferably single-sided embossing, which is formed by passing the base paper after papermaking between a raised embossing roll and a flat roll, but it may also be double-sided embossing, which is formed by passing the paper between a raised embossing roll and a recessed embossing roll. As shown in Figure 2, ply peeling can be prevented by knurling (edge ​​embossing) on ​​the edges of the base paper parallel to the MD direction (Y direction). In ply embossing (processing), known materials can be used for the circumferential surface of the embossing roll.

[0046] In the present invention, the ply embossing may be concave or convex toward the outside of the paper towel roll 1, but a concave shape is preferred.

[0047] (Embossing pattern) The embossed pattern applied to a paper towel 1x (hereinafter also simply referred to as "ply emboss") is not particularly limited, as long as it is formed parallel to the MD direction (Y direction) on both edges in the CD direction (X direction) of the paper towel 1x. For example, in the case of a linear ply emboss, it means that a linear ply emboss is formed parallel to the MD direction on both edges in the CD direction (see Figure 2(a)). In the case of ply embosss other than a linear pattern, such as lines, dots, or designs, it means that the ply emboss is formed parallel to the MD direction on both edges in the CD direction, while maintaining a constant width in the MD direction (Y direction) (see Figures 2(b) and (c)).

[0048] The ply embossing can be linear or dotted, and if linear, it can be solid, dashed, dotted, or double-dotted, and the thickness can be any thickness. Furthermore, there are no particular restrictions on the shape of each individual emboss; it can be circular, elliptical, rectangular, square, wavy, floral, etc.

[0049] An example of a ply embossed pattern is shown in Figure 2. In Figure 2(a), the ply embossed patterns 13 and 14 are formed by two linear embossing lines (13a and 13b, 14a and 14b) parallel to the MD direction (Y direction) of the paper towel 1x (hereinafter also simply referred to as "two-line pattern"). Note that the linear embossing lines of the ply embossed patterns 13 and 14 may be one line or three or more lines.

[0050] Figure 2(b) shows that the ply embossed surfaces 15 and 16 are formed by strip-shaped embossing (15a, 16a) arranged diagonally with respect to the MD direction (Y direction) of the paper towel 1x, and strip-shaped embossing (15b, 16b) arranged symmetrically to these strip-shaped embossing (15a, 16a) (hereinafter also simply referred to as the "V-shape"). Note that the strip-shaped embossing of the ply embossed surfaces 15 and 16 may be in one row or three or more rows.

[0051] Figure 2(c) shows that the ply embossed sheets 17 and 18 are formed by an embossing of three rows of dots (17a, 17b, 17c and 18a, 18b, 18c) parallel to the MD direction (Y direction) of the paper towel 1x (hereinafter also simply referred to as the "dot pattern"). Note that the three rows of dots do not need to be parallel to the CD direction (X direction), and may be offset from each other. Also, the dot pattern embossing of the ply embossed sheets 17 and 18 may consist of one, two, or four or more rows.

[0052] The location where the ply emboss 13-18 is formed is preferably such that the center of the width of the ply emboss is 1% to 35% of the sheet (roll) width from the edge of the paper towel 1x, more preferably 2% to 25%, and even more preferably 3% to 15%.

[0053] (Embossing depth <front side>) The depth of the ply emboss on the front sheet 1a of the product ply of the paper towel 1x (hereinafter also simply referred to as "emboss depth <front side>") is preferably 0.05 mm or more and 0.60 mm or less. If the emboss depth <front side> is less than 0.05 mm, the ply of the paper towel 1x is more likely to peel off. If the emboss depth <front side> exceeds 0.60 mm, the paper towel 1x is more likely to wrinkle. The lower limit of the emboss depth <front side> is more preferably 0.07 mm or more, and even more preferably 0.10 mm or more. The upper limit is more preferably 0.50 mm or less, and even more preferably 0.40 mm or less. In this specification, "ply emboss depth" means the difference in height between the unevenness of the ply emboss 13 to 18 formed on the sheet 1a, and when the ply emboss is concave towards the outside of the paper towel roll 1, the depth of the concave part is measured, and when it is convex, the height of the convex part is measured.

[0054] (Embossing width <front side>) The width of the ply embossing on the front sheet 1a of the product ply of paper towel 1x (hereinafter also simply referred to as "embossing width <front side>") is preferably 2 mm or more and 42 mm or less. If the embossing width <front side> is less than 2 mm, the ply of paper towel 1x is more likely to peel off. If the embossing width <front side> exceeds 42 mm, the paper towel 1x is more likely to wrinkle. The lower limit of the embossing width <front side> is more preferably 3 mm or more, and even more preferably 4 mm or more. The upper limit is more preferably 25 mm or less, and even more preferably 10 mm or less.

[0055] In this specification, the "emboss width" of a ply emboss refers to the distance from edge to edge in the CD direction of each ply emboss formed on sheet 1a, and if this distance varies depending on the emboss shape, the maximum value shall be adopted.

[0056] For example, in the case of a linear "two-line pattern" as shown in Figure 6(a), the distance between the left endpoint of the ply emboss 13a and the right endpoint of the ply emboss 13b, when the sheet 1a is parallel to the CD direction (X direction), is defined as the emboss width (Lwa in Figure 6(a)).

[0057] In the case of a "V-shaped pattern" as shown in Figure 6(b), the maximum distance between the leftmost point of the ply emboss 15a and the rightmost point of the emboss 15b (the distance between the points where the V-shape is widest) when the sheet 1a is parallel to the CD direction (X direction) is defined as the emboss width (Lwb in Figure 6(b)).

[0058] In the case of a three-row "dot pattern" as shown in Figure 6(c), the emboss width (Lwc in Figure 6(c)) is defined as the distance between the leftmost point of the left ply emboss 17a and the rightmost point of the rightmost emboss 17c, with the sheet 1a parallel to the CD direction (X direction).

[0059] (Method for measuring embossing depth and embossing width) The methods for measuring embossing depth and embossing width are explained below with reference to Figures 3 to 6.

[0060] Figure 3(a) is a photograph (shading) showing the height profile of the surface of paper towel 1x on the XY plane as measured by a microscope. Figure 3(b) is an example of the location where the line segment AB is drawn in the cross-section measured on sheet 1a. Figure 4 is a graph showing the height profile at the line segment AB on the XY plane as measured by a microscope in Figure 3(b). Figure 5 is a smoothed graph of the graph in Figure 4, illustrating how the depth of the embossing is determined. Figure 6 shows an example of the location where the line segment AB is drawn for each embossing pattern, showing one of the ply embossings at both ends.

[0061] (1) The embossing depth is measured using a microscope. The microscope used is the "One-Shot 3D Shape Measuring Machine (Head) VR-6100" manufactured by Keyence Corporation. The software used for observing and measuring the microscope image is the "VR-6000 Observation Application" manufactured by Keyence Corporation, and the software used for image analysis is the "VR-6000 Analysis Application" manufactured by the same company. The measurement conditions are a magnification of 12x and a field of view of 24mm x 18mm. The measurement magnification and field of view may be changed as appropriate depending on the desired size of the embossing.

[0062] (2) Using the above microscope, measure the height difference of the emboss to determine the depth of the emboss. Draw line segment AB on the emboss to be measured to obtain the height profile shown in Figure 4. The height profile is a cross-sectional curve S that represents the surface irregularities of the sample.

[0063] (3) The cross-sectional curve S contains noise (steep peaks caused by fiber clumps on the sample surface, fibers extending in a whisker-like manner, or areas without fibers). Therefore, when calculating the height difference of the surface irregularities, such noise peaks are removed. First, a filter is set for the (measured) cross-sectional curve S in Figure 4. In the filter settings, the average filter is selected, the filter type is set to weighted average, and the filter size is set to ±12 to obtain the smoothed cross-sectional curve S' in Figure 5. Note that smoothing using a weighted average filter can be obtained automatically using the analysis software mentioned above.

[0064] (4) The depth of the embossing is calculated from the cross-sectional curve S' (hereinafter also simply referred to as "curve S'") shown in Figure 5. First, in Figure 5, the vertices of the concave parts of curve S' are defined as D1 and D2, starting from the left side (closer to 0 on the horizontal axis (hereinafter also referred to as the "X axis"). Then, on the vertical axis (hereinafter also referred to as the "Y axis"), the maximum curvature point of the convex part on the left side of D1 is defined as H1, the maximum curvature point of the convex part on the right side is defined as H2-1, the maximum curvature point of the convex part on the left side of D2 is defined as H2-2, and the maximum curvature point of the convex part on the right side is defined as H3. Note that curve S' in Figure 5 is the case when the ply embossing is concave toward the outside of the paper towel roll 1. If the ply embossing is convex, the vertices of the convex parts are defined as D1 and D2, and the maximum curvature points of the concave parts are defined as H1, H2-1, H2-2, and H3.

[0065] (5) The depths of the two points D1 and D2, i.e., the "emboss depth (provisional measurement)", are calculated using the following formula. Note that if there are three rows of embossing in the CD direction as shown in Figure 6(c), set D3 and measure the depth of D3 as well. Also, if there is only one concave vertex of the curve S' on the X axis, set D1, H1, and H2-1 in the same way as above, and take the depth of D1 in the formula below as the "emboss depth (provisional measurement)". Depth of D1 = (The larger of the Y-axis values ​​of H1 and H2-1) - Y-axis value of D1 Depth of D2 = (The larger of the Y-axis values ​​of H2 and H3) - Y-axis value of D2

[0066] (6) The distance between H1 and H3, i.e., the "emboss width (provisional measurement)", is calculated using the following formula. Distance between H1 and H3 = X-axis value of H3 - X-axis value of H1

[0067] In this invention, using the measurement methods (1) to (6) described above, measurements are taken at multiple locations as follows to calculate the embossing depth and embossing width.

[0068] (7) Remove three turns of paper towel 1x from the paper towel roll 1, and measure the product ply sheet (hereinafter also simply referred to as "sample") using the fourth turn of paper towel 1x. If the sample has perforations 1c, measure while avoiding them. The surface to be measured is the front sheet 1a of the paper towel 1x, facing outwards.

[0069] (8) First, measure the ply emboss on one side of the ply emboss at both ends of the sample (for example, 13, 15, and 17 in Figure 2). For the measurement, first identify the line segment AB of the uneven cross section to be measured, as shown in Figure 6. Line segment AB includes the individual ply emboss patterns and consists of two points (see Figures 6(b) and 6(c)) that cross the emboss at less than ±45° with respect to the CD direction and less than ±45° with respect to the MD direction. If the emboss pattern is a "two-line pattern" and the ply emboss is connected in the MD direction, then only one measurement point (see Figure 6(a)) at less than ±45° with respect to the CD direction is required. For this line segment AB, measure the emboss depth (provisional measurement) and emboss width (provisional measurement) using the measurement methods described in (1) to (6) above.

[0070] (9) Next, measure the emboss depth (provisional measurement) and emboss width (provisional measurement) of the other ply emboss on the same sample (for example, 14, 16, and 18 in Figure 2) in the same manner as in (8) above. This will give you two measurement results from the sample (the fourth turn of paper towel roll 1).

[0071] (10) Furthermore, the embossing depth (provisional measurement) and embossing width (provisional measurement) are measured at both ends (2 locations) of the 5th turn, both ends (2 locations) of the 6th turn, and both ends (2 locations) of the 7th turn of the paper towel roll 1, in the same manner as in (8) and (9) above. In this way, measurement results are obtained at 8 locations from the paper towel roll 1, and measurement values ​​are obtained at 8 measurement points in the case of the "two-line pattern" in Figure 6(a), and at 16 measurement points in the case of the "V-shape pattern" in Figure 6(b) and the "dot pattern" in Figure 6(c).

[0072] (11) The average value of all measurement points obtained in (10) above shall be defined as the "emboss depth" and "emboss width," respectively.

[0073] In addition to the methods described above, the depth of the embossing can also be determined using a microscope in the following way (not shown in the diagram).

[0074] (1) The microscope used is the VR-6100 one-shot 3D shape measuring machine (head) manufactured by Keyence Corporation. The observation and measurement software for the microscope images is the VR-6000 observation application manufactured by Keyence Corporation, and the image analysis software is the VR-6000 analysis application manufactured by Keyence Corporation. The measurement conditions are a magnification of 12x and a field of view of 24mm x 18mm. The measurement magnification and field of view may be changed as appropriate depending on the desired size of the embossing.

[0075] (2) First, measure the embossing to be measured on the surface side of a paper towel 1x using the "VR-6000 observation application". When measuring, remove three turns of paper towel 1x from the paper towel roll 1, and use the fourth turn of paper towel 1x to measure the product ply in sheet form (hereinafter also referred to as the "measurement sample"). If curl (undulation) is observed in the measurement sample, it is preferable to place weights on both ends of the measurement sample (parts not to be observed) to flatten the curl (undulation) of the measurement sample before measuring.

[0076] (3) Next, use the "VR-6000 Analysis Application" to remove tilt, curl (undulation), etc. from the image measured in (1). In the "VR-6000 Analysis Application", select "Image Processing" and perform "Surface Shape Correction". Select "Distortion Removal" as the correction method. Here, the degree of correction can be adjusted by setting the "Correction Strength" and "Numerical Specification", but setting the "Correction Strength" to 5 is preferable as it will almost completely remove the tilt and curl (undulation) of the sheet of the measured sample. Note that the "Correction Strength" may be changed as appropriate depending on the desired embossing and the condition of the measured sample.

[0077] (4) After completing "Surface Shape Correction," select the "Surface Roughness Measurement" function and define the area in the editing screen where you want to measure the emboss depth. The area should include both the recessed parts of the emboss and the parts without embossing. Use the rectangular numerical specification to set a 10mm x 10mm square area (if the emboss is linear, it may extend beyond the 10mm x 10mm area). If the emboss is larger than a 10mm square, you may change the numerical specification or area setting tool to match the emboss pattern.

[0078] (5) Next, under "Roughness Parameters," select "Sz Maximum Height" (Sz = Sp Maximum Peak Height + Sv Maximum Valley Depth).

[0079] (6) Once the area and parameters have been set, perform the measurement and check the measured value. Here, "Sz maximum height" is defined as the embossing depth. Using this method, "Sz maximum height" can be obtained automatically. Note that even if the ply embossing is convex rather than concave, it can be measured as "Sz maximum height = Sp maximum peak height + Sv maximum valley depth".

[0080] (7) Similarly, the measurement is taken a total of five times (five different embossed areas) while shifting the measurement position of the sample, and the average value of the "Sz maximum height" is finally adopted as the emboss depth.

[0081] (Ratio of embossing depth to paper thickness) When the "paper thickness (product ply)" is A and the "embossing depth (front side)" is B, the value of (B ÷ A × 100) is preferably between 7 and 90. If this value is less than 7, the ply of the paper towel 1x is more likely to peel off. If this value exceeds 90, the paper towel 1x is more likely to wrinkle. The lower limit of this value is more preferably 10 or more, and even more preferably 20 or more. The upper limit is more preferably 80 or less, and even more preferably 55 or less.

[0082] (Sheet length) The sheet length (length in the Y direction shown in Figure 1) between perforations 1c and adjacent perforations 1c of a paper towel 1x is preferably 100 mm or more at the lower limit, more preferably 130 mm or more, and even more preferably 150 mm or more. The upper limit is preferably 250 mm or less, more preferably 230 mm or less, and even more preferably 210 mm or less. If the sheet length is less than 100 mm, the water absorption per sheet of the paper towel 1x will be poor, and if it exceeds 250 mm, the water absorption per sheet will be unnecessarily high.

[0083] (Seat width) The sheet width (hereinafter also referred to as "roll width") (W shown in Figure 1) of a 1x paper towel is preferably 150 mm or more at the lower limit, more preferably 200 mm or more, and even more preferably 250 mm or more. The upper limit is preferably 380 mm or less, more preferably 340 mm or less, and even more preferably 300 mm or less. If the sheet width is less than 150 mm, the water absorption per sheet of the 1x paper towel will be poor, and if it exceeds 380 mm, the water absorption per sheet will be unnecessarily high.

[0084] (DMDT) The Dry Machine Direction Tensile Strength (DMDT) of the product ply of a 1x paper towel in the MD direction during dryness is preferably 7.5 N / 25 mm or higher at the lower limit, more preferably 8.5 N / 25 mm or higher, and even more preferably 9.0 N / 25 mm or higher. The upper limit is preferably 15.0 N / 25 mm or lower, more preferably 14.0 N / 25 mm or lower, and even more preferably 12.0 N / 25 mm or lower. If the DMDT is less than 7.5 N / 25 mm, the basis weight of the 1x paper towel will be lower, resulting in poor water absorption and increased ply delamination. If the DMDT exceeds 15.0 N / 25 mm, the basis weight of the 1x paper towel will be higher, resulting in increased wrinkle formation.

[0085] (DCDT) The dry cross-direction tensile strength (DCDT) of the product ply of a 1x paper towel is preferably 7.5 N / 25 mm or higher at the lower limit, more preferably 8.5 N / 25 mm or higher, and even more preferably 9.0 N / 25 mm or higher. The upper limit is preferably 15.0 N / 25 mm or lower, more preferably 14.0 N / 25 mm or lower, and even more preferably 12.0 N / 25 mm or lower. If the DCDT is less than 7.5 N / 25 mm, the basis weight of the 1x paper towel will be lower, resulting in poor water absorption and increased ply delamination. If the DCDT exceeds 15.0 N / 25 mm, the basis weight of the 1x paper towel will be higher, resulting in increased wrinkle formation.

[0086] The DMDT and DCDT of a 1x paper towel are measured in accordance with JIS P 8113, excluding the perforations 1c of the paper towel.

[0087] (DGMT) For a 1x paper towel, the Dry Geometric Tensile Strength (DGMT) of the product ply is preferably 7.5 N / 25 mm or higher at the lower limit, more preferably 8.5 N / 25 mm or higher, and even more preferably 9.0 N / 25 mm or higher. The upper limit is preferably 15.0 N / 25 mm or lower, more preferably 14.0 N / 25 mm or lower, and even more preferably 12.0 N / 25 mm or lower. If the DGMT is less than 7.5 N / 25 mm, the basis weight of the 1x paper towel will be lower, resulting in poor water absorption and increased ply delamination. If the DGMT exceeds 15.0 N / 25 mm, the basis weight of the 1x paper towel will be higher, resulting in increased wrinkle formation.

[0088] DGMT can be calculated using the geometric mean of DMDT and DCDT. DGMT = (DMDT × DCDT) 1 / 2

[0089] (Water absorption capacity per unit area) The water absorption capacity per unit area of ​​a 1x paper towel ply (hereinafter also simply referred to as "water absorption capacity <per unit area>") is 310 g / m². 2 More than 580g / m 2 The following is the result: Water absorption capacity (per unit area) is 310 g / m². 2 If the value is less than 580 g / m², the water absorption is poor. 2 If it exceeds this limit, the basis weight of each paper towel increases, making them more prone to wrinkling. The lower limit for water absorption per unit area is 360 g / m². 2 The above is preferable, 385 g / m 2 The above is preferable. The upper limit is 520 g / m². 2 The following is preferable: 500g / m 2 The following are preferable.

[0090] (Water absorption capacity <per unit mass>) The water absorption per unit mass of a 1x paper towel product ply (hereinafter also simply referred to as "water absorption <unit mass>") is preferably 7.0 g / g or more and 14.0 g / g or less. If the water absorption <unit mass> is less than 7.0 g / g, the water absorption is poor. If the water absorption <unit mass> exceeds 14.0 g / g, the 1x paper towel becomes prone to wrinkling. The lower limit of the water absorption <unit mass> is more preferably 8.0 g / g or more, and even more preferably 9.0 g / g or more. The upper limit is more preferably 13.0 g / g or less, and even more preferably 12.0 g / g or less.

[0091] The amount of water absorbed by a 1x paper towel in a dry state is measured according to the following method. (1) Take a 2-ply stacked paper towel 1x and cut it using a 76mm square template to create a rectangular test piece 20 with sides of 76mm (see Figure 7). (2) After measuring the mass of the test piece 20 before water absorption using an electronic balance, the test piece 20 is set in the holder 21 (a jig that fixes the test piece 20 at three points, and the jig is made of a metal that does not absorb water). (3) Fill a commercially available tray with distilled water to a depth of 2 cm, and immerse the test piece 20 set in the holder 21 in the distilled water for 2 minutes. (4) After immersion for 2 minutes, remove the test piece 20 together with the holder 21 from the distilled water, and as shown in Figure 7, hang the holder 21 and the test piece 20 from a rod placed in an empty water tank with the corner 20a facing upwards, close the lid of the water tank and leave it for 5 minutes. (5) After that, remove the holder 21 and the test piece 20 from the water bath, remove the holder 21, and measure the mass of the test piece 20 using an electronic balance. (6) The amount of water absorbed per unit area is calculated from the change in mass of the test piece 20 before and after immersion in distilled water, and is the amount of distilled water absorbed per unit area of ​​the test piece 20 (water g / sheet m). 2 , 1m 2 Around. Abbreviated as g / m 2 Calculate (assuming this). (7) Water absorption amount <unit mass> is the amount of water absorbed per unit area (water g / sheet m) 2 This is determined by dividing the water absorption per unit area (water g / sheet m²) by the basis weight of the product ply of the test specimen 20. Specifically, the water absorption per unit area (water g / sheet m²) is calculated by dividing the water absorption per unit area by the basis weight of the product ply of the test specimen 20. 2 ) ÷ Basis weight (sheet g / sheet m) 2 Calculate the water absorption amount (per unit mass) (water g / sheet g, per gram; abbreviated as g / g). (8) Measurements are taken five times for each sample, and the average value is used.

[0092] Furthermore, even if the paper towel 1x is 3-ply, it is preferable to measure it as is, using the same procedure as for 2-ply. This measurement should be performed in accordance with JIS P 8111, at a temperature of 23±1℃ and a humidity of 50±2%. The distilled water should also be maintained at 23±1℃.

[0093] [2] Paper towel roll The above paper towel 1x is wound into a roll on a paper tube 1d to form a paper towel roll 1.

[0094] (Paper tube) The paper tube 1d (hereinafter also referred to as the "core") located in the center of the roll 1 and used to wind the paper towels 1x into a roll shape is preferably a cylindrical paper tube. The material (paper) used for the paper tube 1d preferably contains bleached kraft pulp (BKP) such as bleached hardwood kraft pulp (LBKP) or bleached softwood kraft pulp (NBKP) as pulp fibers. The pulp content (mass%) of the paper used for the paper tube 1d is preferably LBKP:NBKP of 30:70 to 100:0, more preferably 50:50 to 100:0, and even more preferably 70:30 to 100:0. Furthermore, the paper used for the paper tube 1d is preferably made of multiple sheets stacked together from the viewpoint of strength.

[0095] (Paper tube outer diameter) The outer diameter of the paper core 1d (DI in Figure 1) is preferably 28 mm or more at the lower limit, more preferably 33 mm or more, and even more preferably 40 mm or more. The upper limit is preferably 58 mm or less, more preferably 53 mm or less, and even more preferably 46 mm or less. If the outer diameter of the paper core is less than 28 mm, the basis weight will be high in order to achieve a certain roll diameter, making the paper towel 1x more prone to wrinkling. If the outer diameter of the paper core exceeds 58 mm, the basis weight will be low in order to achieve a certain roll diameter, resulting in poor water absorption and increased ply delamination.

[0096] The outer diameter of the paper core is measured using a Diameter Rule manufactured by Muratec KDS Co., Ltd. The measurement is performed by measuring three paper towel rolls and averaging the results.

[0097] (Paper tube mass) The lower limit of the mass of a paper core 1d per 280mm roll width is preferably 10g or more, more preferably 12g or more, and even more preferably 13g or more. The upper limit is preferably 25g or less, more preferably 21g or less, and even more preferably 17g or less. If the paper core mass is less than 10g, the outer diameter of the paper core becomes small, and the basis weight becomes high in order to maintain a constant roll diameter, making the paper towel 1x more prone to wrinkling. If the paper core mass exceeds 25g, the outer diameter of the paper core becomes large, and the basis weight becomes low in order to maintain a constant roll diameter, resulting in poor water absorption and increased ply peeling.

[0098] (winding diameter) The lower limit of the roll diameter (DR in Figure 1) of roll 1 is preferably 124 mm or more, more preferably 130 mm or more, and even more preferably 137 mm or more. The upper limit is preferably 177 mm or less, more preferably 169 mm or less, and even more preferably 159 mm or less. If the roll diameter is less than 124 mm, the basis weight will be low in order to achieve a certain roll length, resulting in poor water absorption and increased ply peeling. If the roll diameter exceeds 177 mm, the basis weight will be high in order to achieve a certain roll length, making the paper towel 1x more prone to wrinkling.

[0099] The winding diameter of roll 1 will be measured using a Diameter Rule manufactured by Muratec KDS Co., Ltd. Three rolls of roll 1 will be measured, and the measurement results will be averaged.

[0100] (Length of volume) The minimum length of roll 1 is preferably 18m or more, more preferably 20m or more, and even more preferably 24m or more. The maximum length is preferably 45m or less, more preferably 40m or less, and even more preferably 35m or less. If the roll length is less than 18m, the basis weight will be high in order to maintain a constant roll diameter, making the paper towel 1x more prone to wrinkling. If the roll length exceeds 45m, the basis weight will be low in order to maintain a constant roll diameter, resulting in poor water absorption and increased ply separation.

[0101] The roll length is measured as follows: First, measure the length of 10 sheets of paper towel 1x between perforation 1c and the adjacent perforation 1c on roll 1. Then, measure the number of sheets on roll 1, and calculate the roll length proportionally from the length of 10 sheets and the number of sheets. For example, if the length of 10 sheets is 1.80m and the number of sheets is 150, then 1.80m × (150 / 10) = 27m. If paper towel roll 1 does not have perforation 1c, measure the roll length directly.

[0102] (winding density) The winding density of roll 1 has a lower limit of 0.29 m / cm². 2 The above is preferable, and 0.32 m / cm 2The above is more preferable, 0.35 m / cm 2 The above is even more preferable. The upper limit is 0.54 m / cm 2 The following is preferred: 0.47 m / cm 2 The following is more preferable: 0.42 m / cm 2 The following is even more preferable: a winding density of 0.29 m / cm². 2 If the basis weight is less than 0.54 m / cm², the paper towel will be more prone to wrinkling. 2 If it exceeds this amount, the basis weight decreases, resulting in poor water absorption and increased ply delamination.

[0103] Winding density is expressed as (winding length × number of plies) ÷ (cross-sectional area of ​​the roll). The cross-sectional area of ​​the roll is expressed as {cross-sectional area of ​​the outer diameter (winding diameter DR) portion of the roll - (cross-sectional area of ​​the outer diameter DI portion of the core)}. For example, in the case of a winding length of 27m, 2 plies, winding diameter DR 150mm, and core outer diameter DI 39mm, winding density = (27m × 2) ÷ {3.14 × (150mm ÷ 2 ÷ 10)} 2 -3.14 × (39mm ÷ 2 ÷ 10) 2} = 0.33 m / cm 2 This is the result.

[0104] (Roll weight <without paper core>) The roll mass of roll 1, excluding the paper core 1d per 280 mm roll width (hereinafter also simply referred to as "roll mass <without paper core>"), is preferably 240 g or more, more preferably 270 g or more, and even more preferably 280 g or more. The upper limit is preferably 520 g or less, more preferably 470 g or less, and even more preferably 450 g or less. If the roll mass <without paper core> is less than 240 g, the basis weight will be low in order to achieve a certain roll length, resulting in poor water absorption and increased ply peeling. If the roll mass <without paper core> exceeds 520 g, the basis weight will be high in order to achieve a certain roll length, making the paper towel 1x more prone to wrinkling.

[0105] (Roll mass <with paper core>) The roll mass (hereinafter also simply referred to as "roll mass <with paper core>") per 280 mm roll width of roll 1, including the paper core 1d, is preferably 255 g or more at the lower limit, more preferably 285 g or more, and even more preferably 295 g or more. The upper limit is preferably 535 g or less, more preferably 485 g or less, and even more preferably 465 g or less. If the roll mass <with paper core> is less than 255 g, the basis weight will be low in order to achieve a certain roll length, resulting in poor water absorption and increased ply peeling. If the roll mass <with paper core> exceeds 535 g, the basis weight will be high in order to achieve a certain roll length, making the paper towel 1x more prone to wrinkling.

[0106] (Roll density) The lower limit of the roll density for roll 1 is 0.04 g / cm³. 3 The above is preferable, and 0.06 g / cm³ 3 The above is preferable, and 0.07 g / cm³ 3 The above is preferable. The upper limit is 0.13 g / cm³. 3 The following is preferable: 0.11 g / cm³ 3 The following is preferable: 0.10 g / cm³ 3 The following is more preferable: Roll density of 0.04 g / cm³ 3 If the basis weight is less than 0.13 g / cm², the water absorption will be poor and the ply will be more prone to peeling. 3 If it exceeds a certain amount, the basis weight increases, making the paper towels (1x) more prone to wrinkling.

[0107] Roll density is expressed as (roll mass) ÷ (roll volume). Roll mass is the mass of one paper towel roll per 280 mm roll width. Roll volume is expressed as [{cross-sectional area of ​​the outer diameter (winding diameter DR) portion of the roll} - (cross-sectional area of ​​the outer diameter DI portion of the core)] × roll width (converted to per 280 mm). For example, if the roll mass (without paper core) per 280 mm roll width is 382 g, the winding diameter DR is 150 mm, and the outer diameter DI of the core is 39 mm, then roll density = 382 g ÷ [{3.14 × (150 mm ÷ 2 ÷ 10) 2 -3.14 × (39mm ÷ 2 ÷ 10) 2} × (280 mm ÷ 10) = 0.08 g / cm3 This is the result.

[0108] [3] Method for manufacturing paper towel rolls A paper towel roll 1 can be manufactured, for example, in the following order: (1) papermaking and creping, (2) ply embossing, and (3) roll winding. In the paper towel manufacturing (papermaking) process of paper towel 1x, it is preferable to use the TAD papermaking method.

[0109] In the papermaking process of (1), it is preferable that a pattern of irregularities derived from the TAD papermaking process, which is different from embossing, is applied to the paper towel 1x. Having this pattern of irregularities further increases the water absorption capacity of the paper towel 1x.

[0110] "TAD papermaking process origin" means that in the papermaking process of paper towel 1x, a textured pattern is applied between the headbox 41 of the papermaking machine and the outlet of the Yankee dryer 46. Specifically, in a part of the papermaking process shown in Figure 8, pulp slurry 40a is sprayed (supplied) from the headbox 41 between the first fabric (forming fabric) 42 and the second fabric (textured fabric) 43, and is drawn onto the second fabric (textured fabric) 43 by the forming roll 44, forming wet paper 40b. Next, the wet paper 40b is dried together with the second fabric (textured fabric) 43 in the through-air dryer 45, and as a result, texture is formed on the dried sheet 40c. Note that in Figure 8, the through-air dryer 45 is equipped with two units, but one unit may be used. Also, a Yankee hood is shown on the Yankee dryer 46, but the hood is not required. Crepes may also be applied in the Yankee dryer 46.

[0111] Furthermore, the textured pattern can be changed as needed by altering the fabric pattern (fine or coarse). Changing the textured pattern to a finer pattern will reduce water absorption. On the other hand, selecting a coarser pattern will make the ply more prone to peeling. Therefore, balance is important when selecting the textured pattern.

[0112] (2) In ply embossing, the base paper obtained by the TAD papermaking process is passed through an embossing roll in a 2-ply or 3-ply laminated state, forming an embossed pattern derived from ply embossing. The pressing force from this ply embossing process increases the adhesive strength between the laminated plies.

[0113] (3) In the roll winding process, the paper towels obtained by ply embossing are wound onto a paper core to form a roll product. A known method may be used for winding.

[0114] As described above, according to this embodiment, even in a paper towel roll made by laminating multiple plies of highly absorbent sheets, it is possible to provide a paper towel roll that does not peel off the plies, does not feel slimy due to the elution of ply bond glue, and does not wrinkle.

[0115] Although the present invention has been described above using embodiments, it goes without saying that the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be obvious to those skilled in the art that various modifications or improvements can be made to the above embodiments. Furthermore, it is clear from the claims that such modified or improved forms may also be included in the technical scope of the present invention. [Examples]

[0116] The present invention will be described in detail below with reference to examples. However, the present invention is not limited in any way to the examples shown below.

[0117] Paper towel rolls for Examples 1-16 and Comparative Examples 1-6, shown in Tables 1-2, were manufactured through the following processes: (1) TAD papermaking and creping, (2) ply embossing, and (3) roll winding. The embossing pattern was the "dot pattern" shown in Figure 2(c). The above parameters were measured for all paper towel rolls of the Examples and Comparative Examples, and the following evaluations were performed. Furthermore, all paper towel rolls of the Examples and Comparative Examples were manufactured and evaluated for use as kitchen towel rolls.

[0118] 1.Water absorption A sensory evaluation of the "water absorption" of manufactured paper towels was conducted by 30 monitors. For each paper towel roll, a single sheet cut along the perforations was used to wipe up 15g of water spilled on a surface. Monitors evaluated the paper towels using their usual methods, selecting either "the sheet has excellent water absorption" or "the sheet has poor water absorption." The evaluation was then categorized into four levels based on the number of people who selected "the sheet has poor water absorption." The evaluation criteria were as follows: ◎: 0-1 person selected "The sheet has poor water absorption." ○: 2-4 people selected "The sheet has poor water absorption." △: 5-7 people selected "The sheet has poor water absorption." ×: The number of people who selected "The sheet has poor water absorption" is 8 or more.

[0119] 2. Resistance to ply peeling A sensory evaluation of the "resistance to ply peeling" in manufactured paper towels was conducted by 30 monitors. For each paper towel roll, a single sheet cut along the perforations was used to wipe up 30g of water spilled on a surface. Monitors evaluated the paper towels using their usual methods, selecting either "no ply peeling" or "ply peeling present." The evaluation was then rated on a 5-point scale based on the number of people who selected "ply peeling present." The evaluation criteria were as follows: ◎: 0-1 person selected "There is peeling of the plywood." ○: 2-4 people selected "There is peeling of the plywood." △: 5-7 people selected "There is peeling of the plywood." ×: 8-15 people selected "There is peeling of the plywood." ××: More than 16 people selected "There is peeling of the plywood".

[0120] 3. Fewer wrinkles A sensory evaluation of the "lack of wrinkles" in manufactured paper towels was conducted by 30 monitors. Monitors visually inspected the outermost, central, and innermost parts of the paper towel roll while pulling out towels, selecting either "wrinkled" or "not wrinkled." The evaluation was then rated on a 5-point scale based on the number of people who selected "wrinkled." The evaluation criteria were as follows: ◎: 0-1 person selected "It has wrinkles" ○: 2-4 people selected "It has wrinkles" △: 5-7 people selected "It has wrinkles" ×: 8-15 people selected "It has wrinkles" ××: More than 16 people selected "It has wrinkles."

[0121] The results obtained are shown in Tables 1 and 2.

[0122] [Table 1]

[0123] [Table 2]

[0124] As is clear from the results shown in Tables 1-2, the paper towel rolls of Examples 1-16 all exhibited good water absorption, resistance to ply peeling, and minimal wrinkling. In contrast, Comparative Examples 1-6 were inferior in any one of these areas: water absorption, resistance to ply peeling, or minimal wrinkling. Furthermore, since no ply bond glue was used for bonding between the plies, the slimy feeling often associated with wet wiping naturally did not occur.

[0125] From the above, it has been confirmed that the present invention can provide a paper towel roll in which multiple plies of highly absorbent sheets are laminated without ply peeling, without a slimy feeling due to the elution of ply bond glue, and without wrinkle formation. [Explanation of Symbols]

[0126] 1: Paper towel roll 1a: Front sheet 1b: Back side sheet 1c: Perforation 1d:Paper tube 1e: The outermost edge of the paper towel roll 1x: Paper towel 13, 14: Ply embossed (two-line pattern) 15, 16: Ply embossed (V-shaped pattern) 17,18: Ply embossed (dot pattern) 20: Test piece 20a: Corner 21: Holder 40a: Pulp Slurry 40b: Wet paper 40c: Dry sheet 41: Headbox 42: First Fabric (Forming Fabric) 43: Second fabric (textured fabric) 44: Foaming Roll 45: Through-air dryer 46: Yankee Hair Dryer

Claims

1. A paper towel roll in which paper towels laminated in 2-ply or 3-ply layers are wound into a roll shape, The aforementioned paper towels It has an embossed pattern created by ply embossing, Basis weight: 30.0 g / m² per ply product ２ 56.0g / m or more ２ below, Water absorption capacity: 310 g / m per ply of product ２ More than 580g / m ２ The following: No plybond glue was used in the aforementioned lamination. A paper towel roll characterized by the following features.

2. The paper towel roll according to claim 1, characterized in that the depth of the embossed pattern is 0.05 mm or more and 0.60 mm or less.

3. The paper towel roll according to claim 1 or 2, characterized in that the width of the embossed pattern is 2 mm or more and 42 mm or less.

4. The paper towel roll according to claim 1 or 2, characterized in that the water absorption capacity of the paper towel is 7.0 g / g or more and 14.0 g / g or less per product ply.

5. The paper towel roll according to claim 1 or 2, characterized in that the paper towel contains 60% by mass or more of wet pulp.

6. The paper towel roll according to claim 1 or 2, characterized in that the paper thickness of the paper towel is 0.42 mm or more and 0.86 mm or less per product ply.

7. The paper towel roll according to claim 1 or 2, characterized in that when the paper thickness per product ply of the paper towel is A and the depth of the embossed pattern is B, the value of (B ÷ A × 100) is 7 or more and 90 or less.

8. The paper towel roll according to claim 1 or 2, characterized in that the paper towel has an uneven surface derived from the TAD papermaking process.

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