Paper towel roll

Abstract

To provide a paper towel roll obtained by winding a paper towel having a high basis weight and a high absorbent property, which satisfies the difficulty in peeling off a tail seal part 3 during manufacturing, the ease of peeling off the tail seal part 3 during use, and a low sticky feeling when wet with water, and has a good holding property.SOLUTION: There is provided a paper towel roll 1 that is obtained by winding a 1-ply sheet mainly composed of pulp fibers and containing synthetic fibers into a roll, and has a tail seal part 3 made by gluing a tail part 4 of a paper towel sheet 1x and an outermost surface of the paper towel roll 1 with a glue. The paper towel roll is configured in that: the paper towel sheet 1x has a basis weight of 40 g / m2 or more and 150 g / m2 or less, and a water absorption of 210 g / m2 or more and 520 g / m2 or less; an amount of a glue applied is 0.5 g or more and 5 g or less; and the paper towel roll 1 has a roll density of 0.05 g / cm3 or more and 0.19 g / cm3 or less, and a winding diameter of 75 mm or more and 160 mm or less.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a paper towel roll.

Background Art

[0002] Paper towels have various uses, such as cleaning oil stains around the kitchen, wiping water, and draining water from food. Therefore, paper towels are required to have excellent absorbency for water and oil, and a strength that does not easily break even when used for cleaning purposes and can withstand continuous use. In order to solve the above problems, various proposals have been made.

[0003] Patent Document 1 describes a method for manufacturing a kitchen paper roll in which a strip-shaped two-ply kitchen paper base fabric is wound into a roll, and a tail portion, which is the end portion of the winding, is adhered to the outermost peripheral surface of the roll with a predetermined adhesive to perform a tail seal (Claim 1). The predetermined adhesive contains a first adhesive and a second adhesive. The first adhesive contains a cellulose-based, starch-based, acrylic resin-based, or a mixture thereof, and is a water-soluble adhesive having a viscosity at 30°C of 5 to 200 mPa·s. The second adhesive contains a polyethylene oxide-based, polyethylene glycol-based, or a mixture thereof, and is a water-soluble adhesive having a viscosity at 30°C of 2000 to 3000 mPa·s. According to Patent Document 1, it is described that poor adhesion of the tail seal during the production of the kitchen paper roll can be prevented, the yield during the production of the kitchen paper roll can be improved, and further, the water absorbency of the kitchen paper that can be used for the kitchen paper roll can be secondarily improved (Paragraph 0018).

[0004] Patent Document 2 describes a method for manufacturing a kitchen paper roll, in which a strip-shaped 2-ply kitchen paper raw material is wound into a roll, and the tail portion, which is the end of the winding, is bonded to the outermost surface of the roll obtained with a predetermined adhesive to perform a tail seal (Claim 1). The predetermined adhesive contains a first adhesive and a second adhesive, the first adhesive being a mixture of a water-soluble adhesive containing cellulose-based, starch-based, acrylic resin-based, or a mixture thereof, with a viscosity of 5 to 200 mPa·s at 30°C, and a polyvinyl alcohol-based water-soluble adhesive with a viscosity of 10,000 to 20,000 mPa·s at 30°C, and the second adhesive being a water-soluble adhesive containing polyethylene oxide-based, polyethylene glycol-based, or a mixture thereof, with a viscosity of 2,000 to 3,000 mPa·s at 30°C. According to Patent Document 2, it is stated that poor adhesion of the tail seal when manufacturing kitchen paper rolls can be prevented, the yield during the manufacturing of kitchen paper rolls can be improved, and as a byproduct, the water absorption of the kitchen paper that can be used for kitchen paper rolls can be improved.

[0005] Patent Document 3 describes a paper roll in which a sealing portion is formed on at least a part of the tail portion or winding start portion, the sealing portion contains cellulose nanofibers, and the dry peel strength of the tail portion or winding start portion in which the sealing portion is formed is 60 to 300 cN as determined by a 180-degree peel test using a Tensilon universal tester (Claim 1). According to Patent Document 3, it is possible to provide a paper roll in which both adhesive strength and ease of peeling are achieved in the sealing portion in which the sealing portion is applied to the paper.

[0006] Patent Document 4 describes a nonwoven wiper obtained by entanglement treatment of a pulp fiber web and a synthetic fiber web using water flow, wherein the average fiber length of the pulp fibers contained in the pulp fiber web is 1.0 to 5.0 mm, and the basis weight of the nonwoven wiper is 20 to 42 g / m². 2A nonwoven wiper is described having a composition ratio of 70-50% by mass of pulp fiber web and 30-50% by mass of synthetic fiber web (Claim 1). According to Patent Document 4, a nonwoven wiper is provided that is easy to use, has a good texture, has an excellent balance with strength, and is also superior in terms of manufacturing cost. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Patent No. 6077795 [Patent Document 2] Patent No. 6077796 [Patent Document 3] Japanese Patent Publication No. 2021-87615 [Patent Document 4] Japanese Patent Publication No. 2018-193634 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] Unlike conventional paper towels, paper towels containing synthetic fibers, which have a high basis weight and excellent water absorption, make it difficult to freely adjust the amount and composition of the glue used for tail sealing (adhesion at the end of the roll) of the paper towel roll.

[0009] For example, while it is preferable to use a small amount of glue on general paper towels, if too little glue is applied to highly absorbent paper towels, the paper towel sheet will absorb the glue, making it difficult to adhere at the tail end, and the tail seal will easily peel off when cutting the paper towel roll with a log saw or when film packaging. Conversely, if too much glue is applied, the glue will dissolve when the paper towel is wet, resulting in a sticky feeling and reduced ease of use. Also, if the glue application area (application width) is too small, the tail seal will easily peel off, while if the application area is too large, it will be difficult to peel off when using the paper towel, resulting in reduced ease of use when wet.

[0010] Furthermore, with typical paper towels, if the basis weight is too high, the sheet absorbs the glue, making the tail seal more likely to peel off. This tendency is even more pronounced with highly absorbent paper towels. Conversely, if the basis weight is lowered to prevent the glue from being absorbed by the sheet, the absorbency will be reduced. Also, if synthetic fibers are included, the absorbency will be significantly reduced because synthetic fibers do not absorb water.

[0011] Furthermore, if the tail of a paper towel roll is too long, the load on the outside of the roll increases when the roll is laid down after winding, making the tail seal more likely to peel off. Conversely, if the tail is too short, it becomes difficult to peel off the paper towels when using them, making them less convenient to use.

[0012] Based on the above, it was difficult to achieve a balance between the amount of glue applied, the length of the tail section, the difficulty of peeling off the tail seal during manufacturing, and the ease of peeling off the tail seal during use with conventional paper towels containing synthetic fibers that have high basis weight and excellent water absorption.

[0013] The object of the present invention is to provide a paper towel roll made by winding a high-basis-weight and highly absorbent paper towel, which achieves both resistance to peeling of the glue portion and tail seal portion during manufacturing, ease of peeling of the glue portion and tail seal portion during use, and low stickiness when wet, and is easy to hold. [Means for solving the problem]

[0014] The inventors of the present invention have conducted extensive research to solve the above problems and have found that when a paper towel sheet containing synthetic fibers and having a predetermined range of high basis weight and high water absorption is wound into a roll, a paper towel roll with desired properties can be obtained, thus completing the present invention. The present invention provides the following paper towel roll.

[0015] (1) A paper towel roll made by winding a 1-ply sheet containing synthetic fibers, mainly composed of pulp fibers, into a roll shape. The tail portion of the paper towel sheet and the outermost outer surface of the paper towel roll are bonded together with glue to form a tail seal portion. The aforementioned paper towel sheet has a basis weight of 40 g / m². 2 More than 150g / m 2 below, Water absorption capacity: 210 g / m² 2 More than 520g / m 2 The following: The amount of glue applied is 0.5g or more and 5g or less. The aforementioned paper towel roll has a roll density of 0.05 g / cm³. 3 More than 0.19g / cm 3 The following are paper towel rolls with a diameter of 75mm or more and 160mm or less. (2) The paper towel roll of (1) above, wherein the application width of the glue is 2 mm or more and 30 mm or less. (3) The paper towel roll according to (1) or (2) above, wherein the length of the tail portion is 4 mm or more and 45 mm or less. (4) A paper towel roll according to any of (1) to (3) above, wherein the thickness of the paper towel is 200 μm or more and 1400 μm or less. (5) Any of the above (1) to (4) paper towel rolls, wherein the peel strength of the glue is 0.6 N / 76 mm or more and 8 N / 76 mm or less. (6) A paper towel roll according to any of (1) to (5) above, wherein the paper towel sheet has an embossed surface and the depth of the emboss is 0.07 mm or more and 1.8 mm or less. (7) Any of the paper towel rolls described in (1) to (6) above, wherein the bending stiffness of the paper towel sheet in the MD direction is 10 μN·m or more and 130 μN·m or less. (8) A paper towel roll according to any of (1) to (7) above, wherein the DMDT of the paper towel sheet is 8N / 25mm or more and 75N / 25mm or less, and the DCDT is 2N / 25mm or more and 50N / 25mm or less. (9) The paper towel roll according to any one of (1) to (8) above, wherein the ratio of the synthetic fiber to the total basis weight of the paper towel sheet is 5 wt% or more and 50 wt% or less, and the ratio of the pulp fiber is 50 wt% or more and 95 wt% or less. (10) The basis weight of the synthetic fiber is 4 g / m 2 or more and 40 g / m 2 or less, and the basis weight of the pulp fiber is 33 g / m 2 or more and 120 g / m 2 or less, for the paper towel roll according to (9) above.

Advantages of the Invention

[0016] According to the present invention, there is provided a paper towel roll wound with a paper towel sheet having a high basis weight and high water absorbency, which achieves both the difficulty of peeling of the tail seal during production and the ease of peeling of the tail seal during use and the low stickiness when wet with water, and has good portability.

Brief Description of the Drawings

[0017] [Figure 1] It is a perspective view schematically showing the appearance of the paper towel roll according to the present embodiment. [Figure 2] It is a schematic perspective view showing a state in which the tail seal of the paper towel roll of FIG. 1 is peeled off and the end portion is pulled out. [Figure 3] It is a diagram showing the height profile on the X-Y plane by a microscope in shading. [Figure 4] It is a diagram showing the height profile on the X-Y plane by a microscope in a graph. [Figure 5] It is a diagram showing how to obtain the depth of the emboss for the emboss pattern. [Figure 6] It is a diagram showing a method for measuring the water absorption amount of the paper towel roll of the present embodiment.

Modes for Carrying Out the Invention

[0018] Figure 1 is a perspective view of the paper towel roll 1 according to this embodiment. Figure 2 is a perspective view showing the paper towel roll 1 of Figure 1 with the tail portion 3 peeled off and the end pulled out. As shown in Figure 2, the surface of the paper towel sheet 1x facing outwards from the roll is sometimes referred to as surface 1a (surface of the paper towel sheet 1x), and the surface facing towards the center of the roll is sometimes referred to as back surface 1b (back surface of the paper towel sheet 1x).

[0019] As shown in Figures 1 and 2, the paper towel roll 1 according to this embodiment is formed by winding an embossed paper towel sheet 1x into a roll shape and applying glue portion 2 (hereinafter also referred to as "tail seal glue 2") along the roll width direction W (roll axis direction) to the end of the roll in the roll winding direction R for adhesion treatment. It is preferable that the paper towel sheet 1x has perforations in the roll width direction W at approximately equal intervals in the roll winding direction R. For the core (center portion, hollow portion in this embodiment) of the paper towel roll 1, for example, a cylindrical body made of paper, plastic, etc. can be used, but a paper core is preferred from the viewpoint of ease of disposal after use. Alternatively, a core may not be used.

[0020] Examples of paper towel rolls 1 include kitchen paper rolls (sometimes called paper towels, cooking paper, etc.) used in home kitchens and restaurant kitchens for wiping up moisture or oil and removing dirt, as well as other rolls of sanitary paper. In all of these cases, a tail portion 3 is formed by applying a glue portion 2 along the roll width direction W to the inside of the end portion of the roll in the winding direction R (i.e., the outermost edge 1c in the winding direction R or its vicinity) during the manufacturing of the roll.

[0021] (Tail seal) The tail seal portion 3 of the paper towel roll 1 is formed by adhering the back surface 1b of the end portion of the paper towel sheet 1x to the surface surface 1a of the radially inward paper towel sheet 1x in order to prevent curling at the end portion of the paper towel roll 1 in the roll winding direction R. The tail seal portion 3 is formed by applying tail seal glue 2 along the roll width direction W at the end portion of the paper towel roll 1 in the roll winding direction R. For example, the tail seal portion 3 can be formed by applying tail seal glue 2 to the surface surface 1a or back surface 1b of the paper towel sheet 1x. In this case, the tail seal glue 2 can be applied to the surface surface 1a of the radially inward paper towel sheet 1x facing the end portion of the paper towel roll 1 to adhere the end portion of the paper towel roll 1 to the radially inward paper towel sheet 1x. Alternatively, the tail seal glue 2 can be applied to the back surface 1b of the paper towel sheet 1x at the end of the paper towel roll 1 to adhere the end of the paper towel roll 1 to the radially inward paper towel sheet 1x, but it is preferable to apply it to the back surface 1b of the paper towel sheet 1x. In this embodiment, the tail seal glue 2 was applied continuously in a straight line along the roll width direction W, but it is not limited to this, and for example, the tail seal glue 2 may be applied at predetermined distances along the roll width direction W.

[0022] (Glue composition) The glue (glue portion 2) used to bond the end portion of the paper towel roll 1 in the winding direction R can be any known type, but it is preferable to use one or more selected from the group consisting of starch, polyvinyl alcohol, and carboxymethylcellulose, with polyvinyl alcohol being more preferable. By using the above composition of glue, it is possible to make a paper towel roll 1 in which the tail seal portion 3 is difficult to peel off during manufacturing and easy to peel off during use, as in this embodiment.

[0023] (Glue application location) The tail seal glue 2 is applied to the paper towel roll 1 at a position (application position) that is a predetermined length L1 away from the outermost edge 1c in the roll winding direction R toward the base end in the roll winding direction R. That is, on the paper towel sheet 1x, a region (tail seal portion 3) is provided that is not adhered to the radially inward paper towel roll 1 on the end side of the roll winding direction R from the application location of the glue portion 2 (tail seal portion 3). The length L1 (the predetermined length L1) of the tail portion 4 of the paper towel sheet 1x on the end side of the roll winding direction R from the glue application location of the glue portion 2 is preferably 4 mm or more and 45 mm or less, more preferably 8 mm or more and 35 mm or less, and even more preferably 12 mm or more and 28 mm or less. If the length L1 of the tail portion 4 of the paper towel sheet 1x is less than 4 mm, it becomes difficult to peel off the tail seal portion 3 when using the paper towel sheet 1x, resulting in poor usability. Furthermore, if the length L1 of the tail portion 4 of the paper towel sheet 1x exceeds 45 mm, the tail portion 4 that peels off from the paper towel roll 1 becomes longer, making it easier for the tail seal portion 3 to peel off due to the weight of the tail portion 4 or snagging on the tail portion 4 during cutting with a log saw or film packaging when manufacturing the paper towel roll 1 (hereinafter also simply referred to as "when manufacturing the paper towel roll 1"). The length L1 of the tail portion 4 of the paper towel sheet 1x is measured at a total of three points: the center in the roll width direction W and 10% from both ends of the roll width, and the average value is used.

[0024] (Glue application width) The coating width L2 of the glue portion 2 according to this embodiment (length of the tail seal portion 3 in the roll winding direction R) is not particularly limited, but from the viewpoint of balancing adhesive strength and ease of peeling, it is preferably 2 mm or more and 30 mm or less, more preferably 5 mm or more and 20 mm or less, and even more preferably 7 mm or more and 13 mm or less. This coating width L2 refers to the length of the glue portion 2 in the roll winding direction R. In this case, the length is measured at a total of three points: the center in the roll width direction W and 10% from both ends of the roll width, and the average value is used. If the coating width L2 of the glue portion 2 is less than 2 mm, the tail seal portion 3 will easily peel off during the manufacture of the paper towel roll 1. Also, if the coating width L2 of the glue portion 2 exceeds 30 mm, the glue portion 2 will dissolve when wet with water during use of the paper towel sheet 1x, resulting in a sticky feeling and poor ease of use.

[0025] (Amount of glue to apply) The amount of glue portion 2 applied per roll is preferably 0.5g to 5g, more preferably 1g to 3.8g, and even more preferably 1.5g to 2.5g. If the amount of glue portion 2 applied per roll is less than 0.5g, the tail seal portion 3 will easily peel off during the manufacturing of the paper towel roll 1. Also, if the amount of glue portion 2 applied per roll exceeds 5g, the glue portion 2 will dissolve when wet with water during use of the paper towel sheet 1x, resulting in a sticky feeling and reduced ease of use. Note that the amount of glue portion 2 applied per roll refers to the amount of glue used per roll (per width of a roll).

[0026] The amount of glue applied to glue section 2 is measured by the following method. First, all sheets (paper towel sheets 1x) containing the area where tail seal glue 2 is applied are taken from a sample of paper towel roll 1. At this time, several turns of sheets are taken not only from the outer sheet but also from the inner sheet. Next, the same number of sheets with the same area as the sheets taken above are taken from the area where tail seal glue 2 is not applied. Then, the weight of each taken sheet is measured, and the amount of tail seal glue 2 applied per roll is calculated using the following formula. Amount of Tail Seal Glue 2 applied per roll = (Total weight of the sheet where Tail Seal Glue 2 is applied) - (Total weight of the sheet where Tail Seal Glue 2 is not applied)

[0027] (Glue peel strength) The peel strength of the adhesive portion (tail seal portion 3) of the paper towel sheet 1x by the glue portion 2 is preferably 0.6N / 76mm or more and 8N / 76mm or less, more preferably 1.0N / 76mm or more and 6N / 76mm or less, and even more preferably 1.4N / 76mm or more and 3.9N / 76mm or less. If the peel strength of the tail seal portion 3 is less than 0.6N / 76mm, the tail seal portion 3 tends to peel off easily during the manufacturing of the paper towel roll 1. Also, if the peel strength of the tail seal portion 3 exceeds 8N / 76mm, it tends to be difficult to peel off the tail seal portion 3 when using the paper towel sheet 1x, resulting in poor usability.

[0028] The tail seal peel strength may be measured using a tensile testing machine (STB-1225S, manufactured by A&D Co., Ltd.) in accordance with the tensile testing method of JIS P 8113, and under the standard conditions specified in JIS P 8111. The tail seal peel strength is measured by the following method: First, two sets of 2-ply sheets, each 76 mm wide and with a radius of R100 mm in the roll winding direction, are taken from a paper towel roll sample, with the ends bonded with tail seal glue 2. At this time, for each set of 2-ply sheets, the area not bonded with tail seal glue 2 should be at least 70 mm continuous. If it is not possible to obtain a continuous area of ​​70 mm not bonded with tail seal glue 2 due to perforations, etc., the area can be shortened to exclude the perforations. In that case, the pitch of the gripping device, as described later, should also be shortened accordingly.

[0029] Next, the 20 mm ends that are not bonded with tail seal glue 2 are clamped and secured with the upper and lower grips. The pitch (spacing) of the grips is 100 mm. Then, the seal is pulled at a tensile speed of 100 mm / min until it is completely peeled off, and the maximum value at that time is taken as the peel strength of the tail seal (N / 76 mm).

[0030] (Wind length and winding diameter) The length of the paper towel roll 1 is not particularly limited, but is preferably 7m to 24m, more preferably 10m to 22m, and even more preferably 13m to 18m. If the length is less than 7m, the roll diameter DR becomes too small, the curvature becomes large, and the rebound of the paper towel sheet 1x increases, so the tail portion 3 tends to peel off easily. Also, if the length exceeds 24m, the roll diameter DR becomes too large, making the paper towel roll 1 difficult to hold by hand, and the ease of use as a roll product tends to be inferior.

[0031] The roll length is determined by measuring the length of 10 sheets of paper towels between the perforations of one paper towel roll. Then, the number of sheets in one paper towel roll is measured, and the roll length is calculated 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 one paper towel roll does not have perforations, the roll length is measured directly.

[0032] The winding diameter DR of the paper towel roll 1 according to this embodiment is preferably 75 mm or more and 160 mm or less, more preferably 100 mm or more and 140 mm or less, and even more preferably 108 mm or more and 130 mm or less. If the winding diameter DR is less than 75 mm, the curvature becomes large, and the rebound of the paper towel sheet 1x increases, making the tail portion 3 more likely to peel off. Also, if the winding diameter DR exceeds 160 mm, the paper towel roll 1 becomes difficult to hold by hand, and the ease of use as a roll product is inferior.

[0033] The roll diameter DR is measured using a Diameter Rule manufactured by Muratec KDS Co., Ltd. The measurement is performed by measuring 10 paper towel rolls and averaging the results.

[0034] (Roll width and roll mass) The roll width of the paper towel roll 1 is not particularly limited, but is preferably 180 mm to 350 mm, more preferably 210 mm to 325 mm, and even more preferably 240 mm to 300 mm. By setting the width within this range, it is possible to provide a paper towel roll 1 with good water absorption and excellent ease of handling, as in this embodiment.

[0035] Furthermore, the roll mass of the paper towel roll 1 is not particularly limited, but is preferably 140g or more and 600g or less, more preferably 220g or more and 450g or less, and even more preferably 250g or more and 400g or less. By keeping it within this range, when using a paper towel roll sheet 1x with good water absorption as in this embodiment, the roll diameter does not become too large, making the paper towel roll 1 easy to handle. Note that the roll mass is the mass per 280mm of roll width, excluding the core (paper tube). If the roll width is not 280mm, it is converted to the mass per 280mm by proportional calculation.

[0036] (Roll density) The roll density of the paper towel roll 1 according to this embodiment is preferably 0.05 g / cm³. 3 More than 0.19g / cm 3 More preferably, 0.07 g / cm³ 3 More than 0.17g / cm 3 More preferably, 0.09 g / cm³ 3 More than 0.15g / cm 3 The following applies: The roll density of paper towel roll 1 is 0.05 g / cm³. 3 If the roll density is less than 0.19 g / cm³, the pressure applied when winding the paper towel roll 1 is weak, resulting in weaker adhesion of the glue portion 2 and making the tail seal portion 3 more prone to peeling off during the manufacturing of the paper towel roll 1. 3If the amount exceeds this limit, the absorbency will be reduced, and because the pressure applied when winding the paper towel roll 1 is too strong, the adhesion of the glue portion 2 will become too strong, making it difficult to peel off the tail seal portion 3 when using the paper towel sheet 1x.

[0037] 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 (paper tube)] × roll width (converted to per 280 mm). For example, if the roll mass (excluding core) per 280 mm roll width is 382 g, the winding diameter DR is 150 mm, and the core outer diameter DI 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 / cm 3 This is the result. If paper towel roll 1 does not have a core, the diameter of the central hole shall be defined as the core outer diameter DI.

[0038] (winding density) The winding density of the paper towel roll 1 according to this embodiment is not particularly limited, but is preferably 0.08 m / cm². 2 More than 0.32m / cm 2 More preferably, 0.10 m / cm 2 More than 0.28m / cm 2 More preferably 0.12 m / cm 2 More than 0.24m / cm 2 The following applies: The winding density of paper towel roll 1 is 0.08 m / cm². 2 If the winding density is less than 0.32 m / cm², the pressure applied to the paper towel roll 1 during winding is weak, resulting in weaker adhesion of the glue portion 2 and a tendency for the tail seal portion 3 to peel off easily during the manufacturing of the paper towel roll 1. 2If the amount exceeds this limit, the absorbency will be poor, and because the pressure applied when winding the paper towel roll 1 is too strong, the adhesion of the glue portion 2 will become too strong, making it difficult to peel off the tail seal portion 3 when using the paper towel sheet 1x.

[0039] 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 (paper tube))}. 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. If paper towel roll 1 does not have a core, the diameter of the central hole is defined as the core outer diameter DI.

[0040] (Core outer diameter) The core outer diameter DI of the paper towel roll 1 according to this embodiment is not particularly limited, but is preferably 25 mm to 55 mm, more preferably 30 mm to 50 mm, and even more preferably 35 mm to 45 mm. By having the core outer diameter DI within the above range, it is possible to maintain the winding diameter and winding density of the paper towel roll 1 while improving the ease of handling of the roll product. The core outer diameter is measured using a Diameter Rule manufactured by Muratec KDS Co., Ltd. The measurement is performed by measuring the core outer diameter DI of 10 paper towel rolls 1 and calculating the average value of the obtained set values. In addition, the mass of the core (paper tube) per 280 mm roll width is not particularly limited, but is preferably 5 g to 22 g, more preferably 7 g to 17 g, and even more preferably 9 g to 13 g.

[0041] <Paper towel sheets> The paper towel sheet 1x used in the paper towel roll 1 according to this embodiment contains synthetic fibers along with pulp fibers and has a high basis weight and high water absorption within a predetermined range described later. This achieves both difficulty in peeling off the tail seal portion 3 during the manufacturing of the paper towel roll 1 and ease of peeling off the tail seal portion 3 and low stickiness when wet when using the paper towel sheet 1x, resulting in a paper towel roll 1 that is easy to hold. If the tail seal portion 3 peels off easily during manufacturing, the defect rate will increase, and a part of the peeled paper towel sheet 1x may get stuck in the process, causing process stoppages and potentially reducing the process operating rate. If the tail seal portion 3 is difficult to peel off during use, a part of the tail seal portion 3 may tear or split in the width direction, potentially causing the problem of not being able to take out a predetermined amount of paper towel sheet 1x at once. Here, synthetic fibers are, for example, those made by spinning various thermoplastic resins into fibers. Furthermore, the paper towel sheet 1x of this embodiment may be 1-ply or 2-ply or more, but 1-ply is preferred from the viewpoint of ease of use and ease of adjusting physical properties. In addition, the paper towel sheet 1x of this embodiment has an embossed surface on all or part of it, as will be described later.

[0042] In this embodiment, the aforementioned effects are obtained by the paper towel sheet 1x having a predetermined high basis weight and high water absorption capacity. However, by adjusting the properties of the paper towel sheet 1x other than basis weight and water absorption capacity to a predetermined range, the aforementioned effects can be further improved. The physical properties of the paper towel used in this embodiment will be described below.

[0043] (Basic weight) In this embodiment, the basis weight of the paper towel sheet 1x is the total basis weight obtained by adding the basis weight of the synthetic fibers contained in the paper towel sheet 1x and the basis weight of the pulp fibers contained in the paper towel sheet 1x. The basis weight of one ply of the paper towel sheet 1x is typically 40 g / m². 2 More than 150g / m 2 Preferably 48 g / m 2 More than 110g / m 2For a more efficient use, use 55g / m 2 More than 80g / m 2 The basis weight of one sheet of paper towels is 40 g / m². 2 Below this weight, the absorbency of the 1x paper towel sheet becomes too low, making it less convenient to use as a roll product. The basis weight of the 1x paper towel sheet is 150g / m². 2 If this limit is exceeded, the absorbency of the paper towel sheet 1x becomes too high, causing it to absorb glue into the interior and reducing the adhesion of the tail seal portion 3, making it easier for the tail seal portion 3 to peel off during the manufacturing of the paper towel roll 1.

[0044] (Basis weight of synthetic fibers, basis weight of pulp fibers) The basis weight of the synthetic fibers contained in the paper towel sheet 1x is not particularly limited, but is preferably 4 g / m². 2 More than 40g / m 2 More preferably 7 g / m 2 More than 30g / m 2 More preferably 10 g / m 2 More than 20g / m 2 The following range applies: The basis weight of the synthetic fiber is 40 g / m². 2 If the basis weight exceeds 4 g / m², the paper towel sheet 1x becomes too hard, resulting in strong resistance when the paper towel sheet 1x is rolled up, and the tail seal portion 3 tends to peel off easily during manufacturing. 2 If the basis weight is less than 33 g / m², the absorbency of the paper towel sheet 1x becomes too high, causing it to absorb glue into the interior and reducing the adhesion of the tail seal portion 3, making the tail seal portion 3 prone to peeling off during the manufacturing of the paper towel roll 1. Furthermore, the basis weight of the pulp fibers contained in the paper towel sheet 1x is preferably 33 g / m². 2 More than 120g / m 2 More preferably 38 g / m² 2 More than 90g / m 2 More preferably 45 g / m 2 More than 75g / m 2 The following applies: The basis weight of the pulp fibers is 120 g / m². 2If the amount exceeds this, the absorbency of the paper towel sheet 1x becomes too high, causing it to absorb the glue deep inside, reducing the adhesion of the glue portion 2, and making the tail seal portion 3 more prone to peeling during manufacturing. Also, the basis weight of the pulp fibers is 33 g / m². 2 Below a certain weight, the absorbency of a 1x paper towel sheet becomes too low, making it less convenient to use as a roll product. Basis weight can be measured according to JIS P 8124.

[0045] (Percentage of synthetic fibers to pulp fibers) The proportion of synthetic fibers contained in the paper towel sheet 1x is not particularly limited, but is preferably 5% to 50% by weight, more preferably 9% to 41% by weight, and even more preferably 12% to 28% by weight of the total amount of paper towel sheet 1x. If the proportion of synthetic fibers exceeds 50% by weight, the water absorption of the paper towel sheet 1x deteriorates, making it less convenient to use as a roll product. If the proportion of synthetic fibers is less than 5% by weight, the water absorption of the paper towel sheet 1x becomes too high, absorbing the glue into the interior and reducing the adhesion of the tail portion 3, making the tail seal portion 3 more likely to peel off during the manufacture of the paper towel roll 1. Furthermore, the proportion of pulp fibers contained in the paper towel sheet 1x is not particularly limited, but is preferably 50% to 95% by weight, more preferably 59% to 91% by weight, and even more preferably 72% to 88% by weight of the total amount of paper towel sheet 1x. If the pulp fiber content exceeds 95% by weight, the absorbency of the paper towel sheet 1x becomes too high, causing it to absorb glue deep inside and reducing the adhesion of the tail seal portion 3, making the tail seal portion 3 prone to peeling off during the manufacturing of the paper towel roll 1. If the pulp fiber content is less than 50% by weight, the absorbency of the paper towel sheet 1x decreases, resulting in a tendency for it to be less user-friendly as a roll product.

[0046] As pulp fibers, general pulp fibers such as bleached softwood kraft pulp (NBKP) and bleached hardwood kraft pulp (LBKP) can be used. The preferred ratio of NBKP to LBKP in the pulp fibers is NBKP:LBKP = 50:50 to 100:0, more preferably NBKP:LBKP = 70:30 to 100:0, even more preferably NBKP:LBKP = 90:10 to 100:0, and most preferably NBKP:LBKP = 100:0. As NBKP, for example, fibers made from radiata pine, slush pine, southern pine, lodgepole pine, spruce, and Douglas fir are preferred. Note that NUKP can be used instead of NBKP, and LUKP can be used instead of LBKP. Furthermore, any synthetic fiber commonly used in this field can be used, such as synthetic fibers spun from synthetic resins like nylon (trademark), vinylon, polyester, acrylic resin, polyethylene, polypropylene, and polystyrene. Synthetic fibers can be used individually or in combination of two or more types.

[0047] Specific examples of paper towel sheets 1 are not particularly limited as long as they contain synthetic fibers and pulp fibers and have a basis weight and water absorption within the aforementioned range, but examples include nonwoven fabrics made by mixing synthetic fibers and pulp fibers, laminates of nonwoven fabrics made of synthetic fibers and pulp fiber webs, and pulp-containing nonwoven fabrics. Among these, pulp-containing nonwoven fabrics are preferred from the viewpoint of toughness and feel. Pulp-containing nonwoven fabrics are, for example, described in U.S. Patent No. 5,284,703, etc., and are made by integrating nonwoven fabric and pulp fibers by a water-flow entanglement method in which pulp fibers are sprayed onto a nonwoven fabric containing synthetic fibers with a high-pressure water stream. In pulp-containing nonwoven fabrics, the synthetic fibers and pulp fibers constituting the nonwoven fabric are intertwined on one surface of the nonwoven fabric to form a pulp fiber web in which the pulp fibers are integrated, and some of the pulp fibers penetrate the nonwoven fabric in the thickness direction and are exposed on the other surface, so that the nonwoven fabric and pulp fiber web are very strongly bonded and integrated. The nonwoven fabric used in the pulp-containing nonwoven fabric is preferably a spunbond nonwoven fabric, and more preferably a spunbond nonwoven fabric containing polypropylene fibers.

[0048] (Water absorption amount) In this embodiment, the water absorption capacity of the paper towel sheet 1x is defined as the water absorption capacity per unit area, but it is also defined as the water absorption capacity per unit weight. In this embodiment, the water absorption capacity (per unit area) is typically 210 g / m². 2 More than 520g / m 2 Preferably 260 g / m² 2 More than 430g / m 2 More preferably, 310 g / m² 2 More than 400g / m 2 The following range applies. Furthermore, the water absorption (per unit weight) is typically 3.0 g / g to 8.0 g / g, preferably 3.5 g / g to 7.5 g / g, and more preferably 4.0 g / g to 7.0 g / g. The water absorption (per unit area) is 520 g / m². 2 If the amount exceeds this, the paper towel sheet 1x will absorb the glue, making the tail seal 3 more likely to peel off during manufacturing. 2 Below this level, the absorbency of a single paper towel sheet decreases, making it less convenient to use. Methods for adjusting the basis weight and water absorption of a paper towel sheet 1x include, for example, adjusting the basis weight of synthetic fibers and pulp fibers, as well as their mixing ratio. In this method, the water absorption also changes depending on whether or not embossing is formed and the depth of the embossing.

[0049] The water absorption capacity of one paper towel sheet is measured as follows: First, a rectangular test specimen with sides of 7.6 cm is prepared by cutting a 1x sheet of 1-ply paper towels using a 7.6 cm (3 inch) square template. The mass of the test specimen before water absorption is measured using an electronic balance. The test specimen is then placed in a holder (a jig that secures the test specimen at three points, and the jig is made of a metal that does not absorb moisture).

[0050] Next, fill a commercially available tray with distilled water to a depth of 2 cm and immerse the test specimen, set in the holder, in the distilled water for 2 minutes. After 2 minutes of immersion, remove the test specimen and holder from the distilled water and attach the strip 210 to one corner 200d of the test specimen 200, as shown in Figure 6. The strip 210 is made by cutting a single-ply paper towel sheet to be measured to a size of 3 mm wide x 38 mm long and attaching it to the part of the test specimen 200 6 mm from corner 200d toward the center. Next, suspend the holder and test specimen 200 from a rod placed in an empty water tank with the corner 200a opposite corner 200d facing upwards, close the lid of the water tank, and leave it for 15 minutes. After that, remove the holder 220 and test specimen 200 from the water tank, remove the strip 210 and holder 220, and measure the mass of the test specimen 200 using an electronic balance. From the change in mass of test piece 200 before and after immersion in distilled water, the 1 m of test piece 200 2 Water absorption capacity of distilled water per sheet (g / m) 2 Calculate the cost per unit area. Furthermore, 1m 2 Water absorption per sheet (g / m²) 2 By dividing ) by the basis weight of the 200 test piece, 1 m 2 Water absorption per sheet (g / m²) 2 ) / Basis weight (sheet g / sheet m 2 Calculate the amount of water absorbed per gram (g of water / g of sheet, per unit weight). Measure each sample 5 times and use the average value.

[0051] This measurement will be conducted according to the JIS P 8111 method, under conditions of 23±1°C and 50±2% humidity. The distilled water will also be maintained at 23±1°C.

[0052] (Sheet length) The length of the sheet between perforations (the length of the paper towel sheet 1x in the roll winding direction R) is not particularly limited, but is preferably 160 mm to 330 mm, more preferably 180 mm to 305 mm, and even more preferably 200 mm to 280 mm. By keeping it within this range, when using a highly absorbent paper towel roll sheet 1x like the one in this embodiment, the area used becomes appropriate, and the amount of water absorbed can be improved.

[0053] (paper thickness) The thickness (per ply) of the paper towel sheet 1x according to this embodiment is not particularly limited, but is preferably 200 μm or more and 1400 μm or less, more preferably 400 μm or more and 1200 μm or less, and even more preferably 500 μm or more and 1000 μm or less. If the paper thickness is less than 200 μm, the water absorption of the paper towel sheet 1x will be poor, and if it exceeds 1400 μm, the water absorption of the paper towel sheet 1x will be too high, absorbing the glue portion 2 and resulting in poor adhesion of the tail seal portion 3, which tends to cause the tail portion 3 to peel off easily during the manufacturing of the paper towel roll 1. The paper thickness was measured using a Peacock paper thickness gauge (manufactured by Ozaki Seisakusho Co., Ltd.) with a single paper towel sheet 1x, and the result was 37.85 gf / cm². 2 The paper thickness is determined by taking measurements under load, repeating the measurement 10 times at different locations, and averaging the measured values.

[0054] (Embossed finish) The paper towel sheet 1x of this embodiment is preferably embossed, and more preferably embossed by a roll winder. The shape of the embossing itself is not particularly limited and can be, for example, circular, elliptical, rectangular, square, floral, polygonal, letters, lines, logos, etc. To obtain a paper towel sheet 1x with high basis weight and excellent water absorption as in this embodiment, a hexagonal shape is preferred.

[0055] In the embossed pattern, the embossing depth is preferably 0.07 mm to 1.8 mm, more preferably 0.2 mm to 1.2 mm, and even more preferably 0.3 mm to 0.8 mm. If the embossing depth is less than 0.07 mm, the aesthetic appeal and water absorption of the paper towel sheet 1x will be inferior, and the ease of use as a roll product will be poor. Also, if the embossing depth exceeds 1.80 mm, the adhesive area of ​​the glue portion 2 will be small, and the tail seal portion 3 will be more likely to peel off during the manufacturing of the paper towel roll 1.

[0056] The depth of the embossing is measured using a microscope. The KEYENCE VR-3100 One-Shot 3D Measurement Microscope can be used. The VR-H1A software can be used for observing, measuring, and analyzing the microscope images. The measurement conditions are 12x magnification and a field of view of 24mm x 18mm. The magnification and field of view may be adjusted as needed depending on the desired embossing size.

[0057] Figure 3 shows the height profile on the XY plane obtained by a microscope, with the height of the surface of the paper towel sheet 1x represented by shades of gray. Linear areas in Figure 3 with different shades from the surrounding areas indicate individual embossing. The depth of the embossing is determined by measuring the height difference of the embossing using the microscope described above. The measurement is performed on the surface 1a side of the paper towel sheet 1x. In addition, three turns of paper towel sheet 1x are removed from the paper towel roll 1, and the measurement is taken using the fourth turn of paper towel sheet 1x in its sheet state. If there are perforations, they are avoided during measurement.

[0058] First, draw line segment AB as shown in Figure 3 to obtain the height profile in Figure 4. Note that line segment AB should be drawn across the embossing. Line segment AB should be drawn in the roll width direction W (CD direction) of the paper towel sheet 1x. However, if the spacing between embossings is narrow, for example, 2 mm or less, and the height of the protrusions described below becomes low, the line segment may be drawn diagonally or in the roll winding direction R. The height profile is the (measured) cross-sectional curve S1 that represents the surface irregularities of the actual paper towel sheet 1x sample, but it also contains noise (steep peaks caused by fiber clumps on the surface of the paper towel sheet 1x, fibers extending in a whisker-like manner, or areas without fibers), and it is necessary to remove such noise peaks when calculating the height difference of the irregularities.

[0059] Therefore, the (measured) cross-sectional curve S1 in Figure 4 is smoothed with a weighted average radio button filter size of ±12 to obtain the cross-sectional curve S2 in Figure 5. Note that smoothing using the weighted average radio button filter can be obtained automatically using the analysis software mentioned above. Then, in the graph shown in Figure 5, the average of the maximum values ​​on the vertical axis of the convex part H1 and the convex part H2 adjacent to convex part H1 is calculated, and the minimum value on the vertical axis at the concave part D1 sandwiched between convex parts H1 and H2 is found. The value obtained by subtracting the minimum value from the average of the maximum values ​​obtained in this way is taken as the provisional embossing depth. Then, as shown in Figure 5, the same measurement is performed at a total of two consecutive locations on the cross-sectional curve (a total of two consecutive locations: the concave part D1 and the concave part D2 sandwiched between convex parts H3 and H4) (at this point, two measurement results are obtained). Subsequently, the paper towel roll 1 is rotated 90 degrees three times in the roll winding direction R of the paper towel sheet 1x, and the same measurements as above are taken at each position (a total of 4 measurement locations in the roll winding direction R). The average value of these 8 locations (2 x 4) is then adopted as the embossing depth.

[0060] (DMDT and DCDT) The dry machine direction tensile strength (DMDT) of a 1x 2-ply paper towel sheet, according to JIS P 8113, is preferably 8N / 25mm to 75N / 25mm, more preferably 13N / 25mm to 65N / 25mm, and even more preferably 20N / 25mm to 50N / 25mm. The dry cross direction tensile strength (DCDT) of a paper towel sheet, according to JIS P 8113, is preferably 2N / 25mm to 50N / 25mm, more preferably 4N / 25mm to 40N / 25mm, and even more preferably 5N / 25mm to 25N / 25mm. If the DMDT of a paper towel sheet 1x exceeds 75N / 25mm and / or the DCDT exceeds 50N / 25mm, the paper towel sheet 1x becomes too hard, resulting in strong resistance when the paper towel sheet 1x is wound up, and the tail seal portion 3 tends to peel off easily during the manufacturing of the paper towel roll 1. If the DMDT of a paper towel sheet 10x is less than 8N / 25mm and / or the DCDT is less than 2N / 25mm, the basis weight of the paper towel sheet 1x becomes low, resulting in poor water absorption.

[0061] (bending and stiffness) The bending stiffness of the paper towel sheet 1x in the MD direction is preferably 10 μN·m or more and 130 μN·m or less, more preferably 17 μN·m or more and 100 μN·m or less, and even more preferably 20 μN·m or more and 50 μN·m or less. If the bending stiffness of the paper towel sheet 1x in the MD direction is less than 10 μN·m, the basis weight of the paper towel sheet 1x will be low and the water absorption will be poor. Also, if the bending stiffness of the paper towel sheet 1x in the MD direction exceeds 130 μN·m, the paper towel sheet 1x will become too hard, the rebound of the paper towel sheet 1x will be strong when wound into a roll, and the tail seal portion 3 will be more likely to peel off during the manufacturing of the paper towel roll 1.

[0062] The bending stiffness of a 1x paper towel sheet in the MD direction can be measured using an L&W bending tester (Lorentzen & Wettre) in accordance with the method described in ISO 2493. For a 1x paper towel sheet test specimen with a width of 38 mm (CD direction) and a length of 100 mm (MD direction), the measured value when the bending angle is 15 degrees and the bending length (span of the sample stage) is 10 mm is taken as the bending resistance (load), and the bending stiffness (μN·m) is calculated using the following formula. If a 100 mm length test specimen cannot be obtained, the length of the test specimen may be shortened. Bending stiffness (μN·m) = 60 × Bending resistance (mN) × Bending length 10 (mm)² ÷ (π × Bending angle 15 (degrees) × Sample width 38 (mm))

[0063] <Method for manufacturing paper towel sheets and paper towel rolls> As for the manufacturing method of paper towel sheets 1x and paper towel rolls 1, if the paper towel sheet 1x is a kitchen towel sheet containing synthetic fibers and pulp fibers, it can be manufactured in the following order: (1) laminating pulp fibers onto a predetermined spunbond nonwoven fabric and entangling with water, (2) heat embossing with matched steel, (3) perforation, and (4) roll winding. In this case, in step (1) water entanglement of the manufacturing method, a nonwoven fabric containing synthetic fibers and pulp fibers is obtained by entangling pulp fibers with synthetic fibers using water. Regarding the method of water entanglement, it is preferable to carry it out by the method described in Japanese Patent Application Publication No. 2018-193634, for example.

[0064] 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 of the invention described in the above embodiments, and it will be clear 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 embodiments with such modifications or improvements may also be included in the technical scope of the present invention. [Examples]

[0065] The embodiment will be described in more detail below with reference to examples and comparative examples.

[0066] (Examples 1-28, Comparative Examples 1-11) Paper towels were produced using synthetic fibers and pulp fibers in the proportions (by weight) shown in Tables 1 and 2, with the paper thickness and sheet length shown in Tables 1 and 2, and embossed, to create single-ply paper towels for Examples 1-28 and Comparative Examples 1-11. Here, polypropylene resin fibers were used as the synthetic fibers. A PVA mixed aqueous solution of less than 10% by weight was used as the glue.

[0067] Using the paper towels obtained from Examples 1-28 and Comparative Examples 1-11, rolls were prepared having the winding diameter, winding length, roll width, roll weight, roll density, tail length, peel strength, glue application amount, and glue application width shown in Tables 1 and 2. The obtained paper towels and rolls were evaluated as follows. The results are shown in Tables 1 to 3.

[0068] [Evaluation Method (Physical Property Evaluation)] Paper thickness: According to the Peacock paper thickness gauge, a single 1x paper towel sheet weighs 37.85 gf / cm². 2 Measurements were taken under load. Bending stiffness: Bending stiffness was measured in accordance with ISO 2493 using an L&W bending tester (Lorentzen & Wettre). For a test specimen with a width of 38 mm and a length of 100 mm, the measured value when the bending angle was 15 degrees and the bending length (span of the sample stage) was 10 mm was used as the bending resistance (load), and the bending stiffness (μN·m) was calculated using the following formula. Bending stiffness (μN·m) = 60 × Bending resistance (mN) × Bending length 10 (mm) 2 ÷(π × bending angle 15(°) × sample width 38(mm)) For DMDT and DCDT, the tensile strengths in the longitudinal and transverse directions were measured in dry conditions according to JIS P9113. Water absorption: A sample piece is prepared by cutting a paper towel into a 75mm x 75mm square, and its dry weight is measured. Next, this sample piece is immersed in distilled water for 2 minutes, and then suspended in a steam-saturated container with one corner of the sample piece as the upper apex, supported by this apex and two adjacent corners, in an extended state (100% RH). After 30 minutes, the weight after draining is measured. A paper towel cut to 3 x 38mm is used for draining. The measured value is then expressed as the water retention per gram of sample piece (g / g), and per 1m 2 Water retention capacity per unit (g / m³) 2 It was converted to ). Embossing depth: The embossing depth is measured using a microscope. The microscope used is the "One-Shot 3D Measuring Macroscope VR-3100" manufactured by KEYENCE. The software used for observing, measuring, and analyzing the microscope images is "VR-H1A". The measurement conditions are 12x magnification and a field of view of 24mm x 18mm. Roll density was calculated using the formula: (roll mass) ÷ (roll volume). The roll mass is the mass of the roll per 280 mm roll width. The roll volume is calculated as [{cross-sectional area of ​​the roll's outer diameter (winding diameter DR) portion} - (cross-sectional area of ​​the core's outer diameter portion)] × roll width (converted to per 280 mm). Peel strength: Dry peel strength determined by a 180-degree peel test using a Tensilon universal tester.

[0069] [Evaluation Method] The manufactured paper towel sheets and paper towel rolls were evaluated based on sensory evaluation or actual measurements regarding the difficulty of peeling the tail seal during manufacturing, the ease of peeling the tail seal during use, water absorption, ease of handling, and stickiness when wet.

[0070] The "resistance to peeling of the tail seal during manufacturing" was evaluated by measuring the number of rolls with peeled tail seals on 30 paper towel rolls after manufacturing, and rating them on a 5-point scale. The evaluation criteria are as follows: ◎: 0-1 rolls with some or all of the tail seal peeled off. ○: 2-4 rolls with some or all of the tail seals peeled off. △: 5-7 rolls with some or all of the tail seals peeled off. ×: 8-14 rolls with some or all of the tail seals peeled off. ××: 15 or more rolls with some or all of the tail seals peeled off.

[0071] The "ease of peeling off the tail seal during use" was evaluated by 30 monitors based on their sensory assessment of how easy it was to peel off the tail seal of a paper towel roll. The evaluation was rated on a 5-point scale based on the number of people who found it "difficult to peel off" or "impossible to peel off." The evaluation criteria were as follows: ◎: 0-1 person found it "difficult to peel off" or "impossible to peel off". ○: 2-4 people felt it was "difficult to peel off" or "impossible to peel off". △: 5-7 people found it "difficult to peel off" or "impossible to peel off". ×: 8-14 people felt it was "difficult to peel off" or "impossible to peel off". ××: 15 or more people felt that it was "difficult to peel off" or "impossible to peel off".

[0072] "Water absorption" was evaluated on a four-point scale by measuring the amount of water absorbed per unit area. The evaluation criteria are as follows: ◎: 330g / m 2 In the above cases ○: 270g / m 2 More than 330g / m 2 When less than △: 230g / m 2 More than 270g / m 2 When less than ×: 230g / m 2 When less than

[0073] "Ease of handling" was evaluated by 30 monitors based on how easy it was to hold the manufactured paper towel rolls. The evaluation was rated on a four-point scale based on the number of people who found them difficult to hold. The evaluation criteria are as follows: ◎: 0-3 people felt it was difficult to hold. ○: 4-6 people felt it was difficult to hold. △: 7-10 people found it difficult to hold. ×: More than 11 people felt it was difficult to hold.

[0074] The "stickiness when wet" was evaluated by 30 monitors based on their sensory assessment of the stickiness of paper towel sheets when wet. The evaluation was rated on a four-point scale based on the number of people who felt the sheets were "sticky." The evaluation criteria were as follows: ◎: 0-3 people felt it was "sticky". ○: 4-6 people felt that it was "sticky". △: 7-10 people felt it was "sticky". ×: More than 11 people felt that it was "sticky".

[0075] [Table 1]

[0076] [Table 2]

[0077] [Table 3]

[0078] From the above, it can be seen that the paper towel roll of this embodiment is a paper towel roll with a high basis weight and high water absorption, and that it is possible to achieve both difficulty in peeling off the tail seal during manufacturing, ease of peeling off the paper towels during use and low stickiness when wet, while also ensuring ease of handling. [Explanation of Symbols]

[0079] 1 paper towel roll 1a surface 1b back side 1c The outermost edge of the paper towel roll 1x Paper Towel Sheet 2 Tail seal glue 3. Tail seal section 4. Tail section 200 test specimens 200a, 200d corner 210 band 220 holder

Claims

1. A paper towel roll is made by winding a 1-ply paper towel sheet, mainly composed of pulp fibers and containing synthetic fibers, into a roll shape. The tail portion of the paper towel sheet and the outermost outer surface of the paper towel roll are bonded together with glue to form a tail seal portion. The aforementioned paper towel sheet has a basis weight of 40 g / m². ２ 150g / m or more ２ below, The thickness is between 200 μm and 1400 μm. The amount of glue applied is 0.5 g or more and 5 g or less. The aforementioned paper towel roll has a roll density of 0.05 g / cm². ３ 0.19g / cm or more ３ The following refers to paper towel rolls with a roll diameter of 75 mm or more and 160 mm or less.

2. The paper towel roll according to claim 1, wherein the application width of the glue is 2 mm or more and 30 mm or less.

3. The paper towel roll according to claim 1 or claim 2, wherein the length of the tail portion is 4 mm or more and 45 mm or less.

4. The paper towel roll according to any one of claims 1 to 3, wherein the peel strength of the glue is 0.6 N / 76 mm or more and 8 N / 76 mm or less.

5. The paper towel roll according to any one of claims 1 to 4, wherein the paper towel sheet has an embossed surface, and the depth of the emboss is 0.07 mm or more and 1.8 mm or less.

6. The paper towel roll according to any one of claims 1 to 5, wherein the bending stiffness of the paper towel sheet in the MD direction is 10 μN·m or more and 130 μN·m or less.

7. The paper towel roll according to any one of claims 1 to 6, wherein the DMDT of the paper towel sheet is 8 N / 25 mm or more and 75 N / 25 mm or less, and the DCDT is 2 N / 25 mm or more and 50 N / 25 mm or less.

8. The paper towel roll according to any one of claims 1 to 7, wherein the proportion of synthetic fibers to the total basis weight is 5% by weight or more and 50% by weight or less, and the proportion of pulp fibers is 50% by weight or more and 95% by weight or less.

9. The basis weight of the aforementioned synthetic fiber is 4 g / m². ２ 40g / m or more ２ The basis weight of the pulp fibers is 33 g / m². ２ 120g / m or more ２ The paper towel roll according to claim 8 is as follows:

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