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 strength that does not easily tear 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 shape, 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 two-ply kitchen paper web 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 obtained roll with a predetermined adhesive to perform tail sealing (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, and a polyvinyl alcohol-based water-soluble adhesive having a viscosity at 30°C of 10,000 to 20,000 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 2,000 to 3,000 mPa·s. According to Patent Document 2, it is described that poor adhesion of the tail seal during the manufacture of the kitchen paper roll can be prevented, the yield during the manufacture 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.

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

[0006] Patent Document 4 discloses a non-woven wiper obtained by hydroentangling a pulp fiber web and a synthetic fiber web, 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 non-woven wiper is 20 to 42 g / m 2There is a non-woven wiper described, where the composition ratio is 70 to 50% by mass of pulp fiber web and 30 to 50% by mass of synthetic fiber web (Claim 1). According to Patent Document 4, a non-woven wiper is provided that is easy to use, has a good texture, is excellent in the balance with strength, and is also excellent in terms of manufacturing cost.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0008] In the case of a paper towel containing synthetic fibers and having a high basis weight and excellent water absorbency, unlike a general paper towel, it is difficult to freely adjust the coating amount and composition of the glue used for the tail seal (adhesion at the end of winding) of the paper towel roll.

[0009] For example, in the case of a general paper towel, it is preferable to reduce the coating amount of the glue. However, in the case of a paper towel with excellent water absorbency, if the coating amount of the glue is too small, the paper towel sheet will absorb the glue, making it difficult to adhere at the tail part, and the tail seal will be easily peeled off during cutting with a log saw or film packaging of the paper towel roll. Conversely, if the coating amount of the glue is too large, when the paper towel is wetted with water during use, the glue will dissolve out, causing a sticky feeling and inferior usability. Also, if the coating area (coating width) of the glue is too small, the tail seal will be easily peeled off. Conversely, if the coating area is too large, it will be difficult to peel off during use of the paper towel, and the usability when wetted with water will be inferior.

[0010] In addition, in the case of a general paper towel, if the basis weight is too high, the sheet absorbs the glue and the tail seal is likely to peel off. In the case of a paper towel with excellent water absorbency, this tendency becomes more prominent. Conversely, if the basis weight is lowered to prevent the glue from being absorbed by the sheet, the water absorbency is poor. In addition, when synthetic fibers are contained, since synthetic fibers do not absorb water, the water absorbency is significantly inferior.

[0011] Furthermore, if the tail part of the paper towel roll is too long, when the roll is laid flat after winding, the load on the outer side of the tail part increases, so the tail seal is likely to peel off. Conversely, if the tail part is too short, it is difficult to peel off during use of the paper towel, resulting in poor usability.

[0012] From the above, in the conventional paper towel containing synthetic fibers with a high basis weight and excellent water absorbency, it has been difficult to achieve both the amount of glue applied, the length of the tail part, the difficulty of peeling the tail seal during manufacturing, and the ease of peeling the tail seal during use.

[0013] An object of the present invention is to provide a paper towel roll wound with a paper towel having a high basis weight and high water absorbency, which achieves both the difficulty of peeling the glue part and the tail seal part during manufacturing, the ease of peeling the glue part and the tail seal part during use, and the low stickiness when wet with water, and has good portability.

Means for Solving the Problems

[0014] As a result of intensive research to solve the above problems, the present inventors have found that when a 1-ply sheet mainly composed of pulp fibers and containing synthetic fibers is wound into a roll, a paper towel roll having desired characteristics can be obtained, and thus the present invention has been completed. The present invention provides the following paper towel roll.

[0015] (1) A paper towel roll obtained by winding a 1-ply sheet mainly composed of pulp fibers and containing synthetic fibers into a roll It has a tail seal part in which the tail part of the paper towel sheet and the outermost peripheral surface of the paper towel roll are adhered by glue. The paper towel sheet has a basis weight of 40 g / m 2 or more and 150 g / m 2 or less. The water absorption is 210 g / m 2 or more and 520 g / m 2 or less, the coating amount of the glue is 0.5 g or more and 5 g or less, the paper towel roll has a roll density of 0.05 g / cm 3 or more and 0.19 g / cm 3 or less, and a roll diameter of 75 mm or more and 160 mm or less, which is a paper towel roll. (2) The paper towel roll according to (1) above, wherein the coating 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 part is 4 mm or more and 45 mm or less. (4) The paper towel roll according to any one of (1) to (3) above, wherein the thickness of the paper towel is 200 μm or more and 1400 μm or less. (5) The paper towel roll according to any one of (1) to (4) above, wherein the peel strength of the glue is 0.6 N / 76 mm or more and 8 N / 76 mm or less. (6) The paper towel roll according to any one of (1) to (5) above, wherein the paper towel sheet has an emboss on its surface, and the depth of the emboss is 0.07 mm or more and 1.8 mm or less. (7) The paper towel roll according to any one of (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) The paper towel roll according to any one of (1) to (7) above, 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. (9) The paper towel roll is the one according to any one of (1) to (8) above, wherein the ratio of the synthetic fiber to the total basis weight is 5% by weight or more and 50% by weight or less, and the ratio of the pulp fiber is 50% by weight or more and 95% by weight 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. The paper towel roll is the one 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 manufacturing 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

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0018] FIG. 1 is a perspective view of the paper towel roll 1 according to the present embodiment. FIG. 2 is a perspective view showing a state in which the tail portion 3 of the paper towel roll 1 in FIG. 1 is peeled off and the end portion is pulled out. As shown in FIG. 2, among the surfaces of the paper towel sheet 1x, the surface directed to the outside of the roll is referred to as the front surface 1a (the surface of the paper towel sheet 1x), and the surface directed to the center portion of the roll may be referred to as the back surface 1b (the back surface of the paper towel sheet 1x).

[0019] As shown in FIGS. 1 and 2, the paper towel roll 1 according to the present embodiment is formed by winding a paper towel sheet 1x provided with an embossed pattern in a roll shape, and applying an adhesive portion 2 (hereinafter also referred to as "tail seal adhesive 2") along the roll width direction W (roll axis direction) on the winding end side in the roll winding direction R for adhesion processing. The paper towel sheet 1x is preferably perforated in the roll width direction W at substantially equal intervals in the roll winding direction R. For the core (central portion, a hollow portion in the present 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 easy disposal after use. Also, the core may not be used.

[0020] Examples of the paper towel roll 1 include a roll body of kitchen paper (sometimes referred to as a paper towel, cooking paper, etc.) used for wiping moisture or oil or removing dirt in a household kitchen or a kitchen in a restaurant, and a roll body of toilet paper, etc. In all of these, at the time of manufacturing the roll body, the tail portion 3 is formed by applying the adhesive portion 2 along the roll width direction W inside the winding end portion (that is, the outermost peripheral edge 1c or its vicinity in the roll winding direction R) in the roll winding direction R.

[0021] (Tail Seal) The tail seal portion 3 of the paper towel roll 1 adheres the back surface 1b of the paper towel sheet 1x at the end portion in the roll winding direction R of the paper towel roll 1 to the front surface 1a of the paper towel sheet 1x on the radially inner side in order to prevent the end portion in the roll winding direction R of the paper towel roll 1 from unrolling. The tail seal portion 3 is formed by applying the tail seal glue 2 along the roll width direction W at the end portion in the roll winding direction R of the paper towel roll 1. For example, the tail seal portion 3 can be formed by applying the tail seal glue 2 to the front surface 1a or the back surface 1b of the paper towel sheet 1x. At this time, by applying the tail seal glue 2 to the front surface 1a of the paper towel sheet 1x on the radially inner side facing the end portion in the roll winding direction of the paper towel roll 1, the end portion in the roll winding direction of the paper towel roll 1 can be adhered to the paper towel sheet 1x on the radially inner side. Alternatively, the tail seal glue 2 can be applied to the back surface 1b of the paper towel sheet 1x at the end portion in the roll winding direction of the paper towel roll 1 to adhere the end portion in the roll winding direction of the paper towel roll 1 to the paper towel sheet 1x on the radially inner side, but it is preferable to apply it to the back surface 1b of the paper towel sheet 1x. In addition, in the present embodiment, the tail seal glue 2 is applied linearly and continuously along the roll width direction W, but it is not limited to this. For example, the tail seal glue 2 may be applied at a predetermined distance apart in the roll width direction W.

[0022] (Composition of glue) As the glue (glue portion 2) for adhering the end portion in the roll winding direction R of the paper towel roll 1, a known one can be used, but it is preferable to use one or more selected from the group consisting of starch, polyvinyl alcohol, and carboxymethyl cellulose, and polyvinyl alcohol is more preferable. By making the glue have the above composition, it is possible to obtain a paper towel roll 1 in which the tail seal portion 3 is difficult to peel off during production and the tail seal portion 3 is easy to peel off during use as in the present embodiment.

[0023] (Application position of glue) The tail seal glue part 2 is applied at a position (coating position) spaced a predetermined length L1 from the outermost peripheral edge 1c in the roll winding direction R of the paper towel roll 1 toward the proximal side in the roll winding direction R. That is, on the winding end side in the roll winding direction R of the paper towel sheet 1x with respect to the coating position of the glue part 2 (tail seal part 3), a region (tail seal part 3) that is not adhered to the paper towel roll 1 on the radially inner side is provided. The length L1 (the above-mentioned predetermined length L1) of the tail part 4 of the paper towel sheet 1x on the winding end side in the roll winding direction R with respect to the glue coating position of the glue part 2 is preferably 4 mm or more and 45 mm or less, more preferably 8 mm or more and 35 mm or less, and still more preferably 12 mm or more and 28 mm or less. When the length L1 of the tail part 4 of the paper towel sheet 1x is less than 4 mm, it becomes difficult to peel off the tail seal part 3 when using the paper towel sheet 1x, and it is inferior in usability. Further, when the length L1 of the tail part 4 of the paper towel sheet 1x exceeds 45 mm, the tail part 4 peeled from the paper towel roll 1 becomes long, so when cutting with a log saw or film packaging during the manufacture of the paper towel roll 1 (hereinafter also simply referred to as "during the manufacture of the paper towel roll 1"), the tail seal part 3 is likely to be peeled off due to the weight of the tail part 4 or being caught on the tail part 4. Incidentally, the length L1 of the tail part 4 of the paper towel sheet 1x is measured at a total of three points, namely, the center part in the roll width direction W and the positions 10% from both ends with respect to the roll width, and the average value thereof is taken.

[0024] (Glue coating width) The application width L2 of the glue part 2 according to this embodiment (the length in the roll winding direction R of the tail seal part 3) is not particularly limited. However, from the viewpoint of achieving both adhesion 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 still more preferably 7 mm or more and 13 mm or less. This application width L2 refers to the length of the glue part 2 in the roll winding direction R. At that time, the length is measured at a total of three points: the center part in the roll width direction W and the positions 10% from both ends with respect to the roll width, and the average value is taken. If the application width L2 of the glue part 2 is less than 2 mm, the tail seal part 3 is likely to peel off during the manufacture of the paper towel roll 1. Further, if the application width L2 of the glue part 2 exceeds 30 mm, when the glue part 2 melts out when wet with water during the use of the paper towel sheet 1x, a sticky feeling is felt and the ease of use is poor.

[0025] (Amount of glue applied) The amount of glue applied to the glue part 2 is preferably 0.5 g or more and 5 g or less, more preferably 1 g or more and 3.8 g or less, and still more preferably 1.5 g or more and 2.5 g or less per roll. If the amount of glue applied to the glue part 2 per roll is less than 0.5 g, the tail seal part 3 is likely to peel off during the manufacture of the paper towel roll 1. Further, if the amount of glue applied to the glue part 2 per roll exceeds 5 g, when wet with water during the use of the paper towel sheet 1x, the glue part 2 melts out, a sticky feeling is felt and the ease of use is poor. Note that the amount of glue applied to the glue part 2 per roll means the amount of glue used per roll (per roll width).

[0026] The amount of glue applied to the glue part 2 is measured by the following method. First, all the sheets (paper towel sheets 1x) including the portions where the tail seal glue 2 is applied are collected from the sample of the paper towel roll 1. At this time, several turns of the inner wound sheets are also collected in addition to the outer peripheral sheets. Next, sheets at locations where the tail seal glue 2 is not applied are collected in the same area and the same number of sheets as the sheets collected above. Next, the weights of the collected sheets are measured, and the amount of tail seal glue 2 applied per roll is calculated by the following calculation formula. Coating amount of tail seal glue group 2 per roll = (Total weight of the sheet at the location where tail seal glue group 2 is applied) - (Total weight of the sheet at the location where tail seal glue group 2 is not applied)

[0027] (Glue peel strength) The peel strength of the adhesion part (tail seal part 3) of the paper towel sheet 1x by the glue part 2 is preferably 0.6 N / 76 mm or more and 8 N / 76 mm or less, more preferably 1.0 N / 76 mm or more and 6 N / 76 mm or less, and still more preferably 1.4 N / 76 mm or more and 3.9 N / 76 mm or less. When the peel strength of the tail seal part 3 is less than 0.6 N / 76 mm, the tail seal part 3 tends to be easily peeled off during the manufacture of the paper towel roll 1. Also, when the peel strength of the tail seal part 3 exceeds 8 N / 76 mm, it becomes difficult to peel off the tail seal part 3 when using the paper towel sheet 1x, and there is a tendency for it to be inferior in terms of ease of use.

[0028] The measurement of the tail seal peel strength can be carried out using a tensile testing machine (STB - 1225S, manufactured by A&D Company, Limited) in accordance with the tensile test method of JIS P 8113, and is carried out under the standard conditions specified in JIS P 8111. Note that the tail seal peel strength is measured by the following method. First, take two test pieces of two plies each with a width of 76 mm in the width direction and a length of 100 mm in the roll winding direction R from the sample of the paper towel roll, with the end adhered by the tail seal glue group 2. At this time, for each of the two test pieces of two plies each, ensure that the non - adhered part by the tail seal glue group 2 is continuous for 70 mm or more. If the non - adhered part by the tail seal glue group 2 cannot be continuously collected for 70 mm due to perforations or the like, it can be shortened within the range not including the perforations. In that case, the pitch of the gripping tool described later is also shortened accordingly.

[0029] Next, clamp and fix the 20 mm ends that are not adhered by the tail seal group 2 with the upper and lower grippers. The pitch (spacing) of the grippers shall be 100 mm. Next, pull at a pulling speed of 100 mm / min until complete peeling, and the maximum value at that time shall be the peel strength (N / 76 mm) of the tail seal.

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

[0031] For the roll length, measure the length of 10 sheets of the paper towel sheet 1x between the perforations of the paper towel roll 1. Then, measure the number of sheets of the paper towel roll 1, and the roll length is obtained by proportional calculation from the length of 10 sheets and the number of sheets. For example, when the length of 10 sheets is 1.80 m and the number of sheets is 150 sheets, it becomes 1.80 m × (150 / 10) = 27 m. If there are no perforations on the paper towel roll 1, measure the roll length.

[0032] The roll 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 still more preferably 108 mm or more and 130 mm or less. If the roll diameter DR is less than 75 mm, the curvature becomes large and the repulsion of the paper towel sheet 1x becomes large, so the tail portion 3 tends to peel off easily. Also, if the roll diameter DR exceeds 160 mm, it becomes difficult to hold the paper towel roll 1 by hand, and it is inferior in terms of ease of use as a roll product.

[0033] The winding diameter DR of the roll is measured using a diameter rule manufactured by Muratec KDS Co., Ltd. The measurement is performed on 10 paper towel rolls 1, and the measurement results are averaged.

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

[0035] Also, the roll mass of the paper towel roll 1 is not particularly limited, but is preferably 140 g or more and 600 g or less, more preferably 220 g or more and 450 g or less, and still more preferably 250 g or more and 400 g or less. By setting it within this range, when using the paper towel roll sheet 1x having good water absorption as in this embodiment, the paper towel roll 1 can be made easy to handle without the winding diameter becoming too large. Note that the roll mass is the mass per 280 mm of roll width excluding the core (paper tube). When the roll width is not 280 mm, it is converted to the mass per 280 mm by proportional calculation.

[0036] (Roll density) The roll density of the paper towel roll 1 according to this embodiment is preferably 0.05 g / cm 3 or more and 0.19 g / cm 3 or less, more preferably 0.07 g / cm 3 or more and 0.17 g / cm 3 or less, and still more preferably 0.09 g / cm 3 or more and 0.15 g / cm 3 or less. If the roll density of the paper towel roll 1 is less than 0.05 g / cm 3 , the pressing force during winding of the paper towel roll 1 is weak, so the adhesion of the glued portion 2 becomes weak, and the tail seal portion 3 is likely to peel off during the manufacture of the paper towel roll 1. Also, if the roll density of the paper towel roll 1 is 0.19 g / cm 3When it exceeds this value, the water absorbency is poor, and since the pressing force during the winding of the paper towel roll 1 is strong, the adhesion of the glue part 2 becomes too strong, making it difficult to peel off the tail seal part 3 when using the paper towel sheet 1x.

[0037] The roll density is expressed as (roll mass)÷(roll volume). The roll mass is the mass of the paper towel roll 1 per roll width of 280 mm. The roll volume is expressed as [{cross-sectional area of the outer diameter (winding diameter DR) part of the roll} - (cross-sectional area of the outer diameter DI part of the core (paper tube))]×roll width (converted to per 280 mm). For example, when the roll mass (excluding the core) per roll width of 280 mm is 382 g, the winding diameter DR is 150 mm, and the core outer diameter DI is 39 mm, the roll density = 382 g÷[{3.14×(150 mm÷2÷10) 2 - 3.14×(39 mm÷2÷10) 2}×(280 mm÷10)] = 0.08 g / cm 3 This is the result. When there is no core in the paper towel roll 1, the diameter of the central hole is taken 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 preferably 0.08 m / cm 2 or more and 0.32 m / cm 2 or less, more preferably 0.10 m / cm 2 or more and 0.28 m / cm 2 or less, still more preferably 0.12 m / cm 2 or more and 0.24 m / cm 2 or less. When the winding density of the paper towel roll 1 is less than 0.08 m / cm 2 Since the pressing force during the winding of the paper towel roll 1 is weak, the adhesion of the glue part 2 becomes weak, and the tail seal part 3 tends to be easily peeled off during the manufacture of the paper towel roll 1. Also, when the winding density of the paper towel roll 1 is 0.32 m / cm 2When it exceeds this value, the water absorption property deteriorates, and since the pressing force during winding of the paper towel roll 1 is strong, the adhesion of the glued part 2 becomes too strong, and when using the paper towel sheet 1x, the tail seal part 3 tends to be difficult to peel off.

[0039] The 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) part of the roll - cross-sectional area of the outer diameter (core (paper tube) diameter DI) part}. For example, when the winding length is 27 m, the number of plies is 2, the winding diameter DR is 150 mm, and the core outer diameter DI is 39 mm, the winding density = (27 m × 2) ÷ {3.14 × (150 mm ÷ 2 ÷ 10) 2 - 3.14 × (39 mm ÷ 2 ÷ 10) 2}= 0.33 m / cm 2 This is the case. When there is no core in the paper towel roll 1, the diameter of the center hole is taken as the core outer diameter DI.

[0040] (core outer diameter) The core outer diameter DI, which is the outer diameter of the core of the paper towel roll 1 according to the present embodiment, is not particularly limited, but is preferably 25 mm or more and 55 mm or less, more preferably 30 mm or more and 50 mm or less, and still more preferably 35 mm or more and 45 mm or less. When the core outer diameter DI is within the above range, while suitably maintaining the winding diameter and winding density of the paper towel roll 1, the portability of the roll product can be made good. The core outer diameter is measured using a diameter rule manufactured by Muratec KDS Co., Ltd. The measurement is to measure the core outer diameter DI for 10 paper towel rolls 1 and obtain the average value of the measured values obtained. Also, the mass of the core (paper tube) per 280 mm of the roll width is not particularly limited, but is preferably 5 g or more and 22 g or less, more preferably 7 g or more and 17 g or less, and still more preferably 9 g or more and 13 g or less.

[0041] <paper towel sheet> The paper towel sheet 1x used for the paper towel roll 1 according to this embodiment contains synthetic fibers together with pulp fibers, and has a high basis weight and a high water absorption within a predetermined range described later. By doing so, it is possible to achieve both the difficulty of peeling of the tail seal portion 3 during the production of the paper towel roll 1 and the ease of peeling of the tail seal portion 3 when using the paper towel sheet 1x, as well as a small amount of stickiness when wet with water, and a paper towel roll 1 with good portability can be obtained. If the tail seal portion 3 is easily peeled off during production, the defective rate will increase. Also, a part of the peeled paper towel sheet 1x may be pinched during the process, causing a process stop or the like, and there is a risk of a decrease in the process operation rate. If the tail seal portion 3 is difficult to peel off during use, there is a risk that a part of the tail seal portion 3 will be torn or the tail seal portion 3 will split in the width direction, resulting in a problem that a predetermined amount of the paper towel sheet 1x cannot be taken out at once. Here, the synthetic fiber is, for example, a fiber obtained by spinning various thermoplastic resins into a fibrous form. Further, the paper towel sheet 1x of this embodiment may be 1 ply or 2 plies or more, but 1 ply is preferable from the viewpoints of ease of use and ease of adjusting physical properties. Further, as will be described later, the paper towel sheet 1x of this embodiment is provided with an emboss on the whole or a part thereof.

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

[0043] (Basis weight) The basis weight of the paper towel sheet 1x of this embodiment 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 1 ply of the paper towel sheet 1x is usually 40 g / m 2 or more and 150 g / m 2 or less, preferably 48 g / m 2 or more and 110 g / m 2Hereinafter, more preferably 55 g / m 2 or more and 80 g / m 2 or less. If the basis weight of the paper towel sheet 1x is less than 40 g / m 2 , the water absorbency of the paper towel sheet 1x becomes too low, and it is inferior in ease of use as a roll product. If the basis weight of the paper towel sheet 1x exceeds 150 g / m 2 , the water absorbency of the paper towel sheet 1x becomes too high, absorbs the glue to the inside, and the adhesiveness of the tail seal portion 3 decreases, and the tail seal portion 3 is likely to peel off during the production of the paper towel roll 1.

[0044] (Synthetic fiber basis weight, pulp fiber basis weight) The basis weight of the synthetic fiber contained in the paper towel sheet 1x is not particularly limited, but preferably 4 g / m 2 or more and 40 g / m 2 or less, more preferably 7 g / m 2 or more and 30 g / m 2 or less, still more preferably 10 g / m 2 or more and 20 g / m 2 or less. When the basis weight of the synthetic fiber exceeds 40 g / m 2 , the paper towel sheet 1x becomes too hard, and the repulsion becomes strong when the paper towel sheet 1x is wound into a roll, and the tail seal portion 3 is likely to peel off during production. When the basis weight of the synthetic fiber is less than 4 g / m 2 , the water absorbency of the paper towel sheet 1x becomes too high, absorbs the glue to the inside, and the adhesiveness of the tail seal portion 3 decreases, and the tail seal portion 3 is likely to peel off during the production of the paper towel roll 1. Also, the basis weight of the pulp fiber contained in the paper towel sheet 1x is preferably 33 g / m 2 or more and 120 g / m 2 or less, more preferably 38 g / m 2 or more and 90 g / m 2 or less, still more preferably 45 g / m 2 or more and 75 g / m 2 or less. When the basis weight of the pulp fiber is 120 g / m 2When it exceeds, the water absorbency of the paper towel sheet 1x becomes too high, absorbs the glue to the inside, the adhesiveness of the glue part 2 decreases, and the tail seal part 3 tends to be easily peeled off during manufacturing. Also, when the basis weight of the pulp fiber is less than 33 g / m 2 When it is less than, the water absorbency of the paper towel sheet 1x becomes too low, and it tends to be inferior in usability as a roll product. The basis weight can be measured based on JIS P 8124.

[0045] (Content ratio of synthetic fiber and pulp fiber) The ratio of the synthetic fiber contained in the paper towel sheet 1x is not particularly limited, but it is preferably 5% by weight or more and 50% by weight or less, more preferably 9% by weight or more and 41% by weight or less, still more preferably 12% by weight or more and 28% by weight or less, based on the total amount of the paper towel sheet 1x. When the content ratio of the synthetic fiber exceeds 50% by weight, the water absorbency of the paper towel sheet 1x deteriorates, and it tends to be inferior in usability as a roll product. When the content ratio of the synthetic fiber is less than 5% by weight, the water absorbency of the paper towel sheet 1x becomes too high, absorbs the glue to the inside, the adhesiveness of the tail part 3 decreases, and the tail seal part 3 tends to be easily peeled off during the manufacture of the paper towel roll 1. Also, the ratio of the pulp fiber contained in the paper towel sheet 1x is not particularly limited, but it is preferably 50% by weight or more and 95% by weight or less, more preferably 59% by weight or more and 91% by weight or less, still more preferably 72% by weight or more and 88% by weight or less, based on the total amount of the paper towel sheet 1x. When the content ratio of the pulp fiber exceeds 95% by weight, the water absorbency of the paper towel sheet 1x becomes too high, absorbs the glue to the inside, the adhesiveness of the tail seal part 3 decreases, and the tail seal part 3 tends to be easily peeled off during the manufacture of the paper towel roll 1. When the content ratio of the pulp fiber is less than 50% by weight, the water absorbency of the paper towel sheet 1x deteriorates, and it tends to be inferior in usability as a roll product.

[0046] As the pulp fibers, common pulp fibers such as softwood kraft pulp (NBKP) and hardwood kraft pulp (LBKP) can be used. The content ratio of NBKP and LBKP in the pulp fibers is preferably NBKP:LBKP = 50:50 to 100:0, more preferably NBKP:LBKP = 70:30 to 100:0, still more preferably NBKP:LBKP = 90:10 to 100:0, and most preferably NBKP:LBKP = 100:0. As NBKP, for example, fibers composed of radiata pine, slash 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. Also, as synthetic fibers, any commonly used ones in this field can be used, for example, synthetic fibers spun from synthetic resins such as nylon (trademark name), vinylon, polyester, acrylic resin, polyethylene, polypropylene, and polystyrene. The synthetic fibers can be used alone or in combination of two or more.

[0047] Specific examples of the paper towel sheet 1 are not particularly limited as long as they contain synthetic fibers and pulp fibers and have a basis weight and water absorbency within the aforementioned ranges. For example, non-woven fabrics obtained by co-papering synthetic fibers and pulp fibers, laminates of non-woven fabrics made of synthetic fibers and pulp fiber webs, pulp-containing non-woven fabrics, etc. can be mentioned. Among these, from the viewpoints of toughness, touch, etc., pulp-containing non-woven fabrics are preferred. The pulp-containing non-woven fabric is, for example, as described in U.S. Patent No. 5,284,703, etc., and is obtained by integrating a non-woven fabric and pulp fibers by a water jet entanglement method in which pulp fibers are sprayed onto a non-woven fabric containing synthetic fibers with a high-pressure water stream. In the pulp-containing non-woven fabric, a pulp fiber web in which the synthetic fibers and pulp fibers constituting the non-woven fabric are intertwined and the pulp fibers are integrated is formed on one surface of the non-woven fabric, and a part of the pulp fibers penetrates through the non-woven fabric in the thickness direction and is exposed on the other surface, and the non-woven fabric and the pulp fiber web are extremely firmly bonded and integrated. As the non-woven fabric used for the pulp-containing non-woven fabric, preferably a spunbond non-woven fabric, more preferably a spunbond non-woven fabric containing polypropylene fibers can be mentioned.

[0048] (Water absorption) In this embodiment, the water absorption of the paper towel sheet 1x is defined as the water absorption per unit area, but it can also be defined as the water absorption per unit weight. In this embodiment, the water absorption (per unit area) is usually 210 g / m 2 or more and 520 g / m 2 or less, preferably 260 g / m 2 or more and 430 g / m 2 or less, more preferably 310 g / m 2 or more and 400 g / m 2 or less. Also, the water absorption (per unit weight) is usually 3.0 g / g or more and 8.0 g / g or less, preferably 3.5 g / g or more and 7.5 g / g or less, more preferably 4.0 g / g or more and 7.0 g / g or less. If the water absorption (per unit area) exceeds 520 g / m 2 , the paper towel sheet 1x will absorb the glue, and the tail seal part 3 will be easily peeled off during manufacturing. If the water absorption (per unit area) is less than 210 g / m 2 , the water absorption of the paper towel sheet 1x will decrease, and it will be inferior in usability. As a method for adjusting the basis weight and water absorption of the paper towel sheet 1x, for example, a method of adjusting the basis weight of each of the synthetic fiber and the pulp fiber and their mixing ratio can be mentioned. In this method, the water absorption also changes depending on the presence or absence of embossing and the embossing depth.

[0049] The water absorption of the paper towel sheet 1x is measured as follows. First, cut from a single-ply paper towel sheet 1x using a template in the shape of a square with one side being 7.6 cm (3 inches) to produce a test piece in the shape of a rectangle with one side being 7.6 cm. Measure the mass of the test piece before water absorption with an electronic balance. Set the test piece in a holder (a jig for fixing three points of the test piece, and the jig is made of a metal that does not absorb moisture).

[0050] Next, pour 2 cm of distilled water into a commercially available bat, and immerse the test piece set in the holder in the distilled water for 2 minutes. After 2 minutes of immersion, take out the test piece together with the holder from the distilled water, and attach a strip 210 to one corner 200d of the test piece 200 as shown in Fig. 6. The strip 210 is cut from the measuring paper towel sheet (1 ply) to a size of 3 mm in width × 38 mm in length, and attached to a portion 6 mm from the corner 200d of the test piece 200 towards the center. Next, hang the holder and the test piece 200 on a rod installed in an empty water tank with the corner 200a facing the corner 200d upwards, close the lid of the water tank, and leave it for 15 minutes. Then, take out the holder 220 and the test piece 200 from the water tank, remove the strip 210 and the holder 220, and measure the mass of the test piece 200 with an electronic balance. From the mass change of the test piece 200 before and after immersion in distilled water, the water absorption amount of distilled water per 1 m 2 of the test piece 200 (g of water / sheet m 2 , per unit area) is calculated. Further, by dividing the water absorption amount per 1 m 2 of the test piece 200 (g of water / sheet m 2 ) by the basis weight of the test piece 200, the water absorption amount per 1 m 2 of the test piece 200 (g of water / sheet m 2 ) / basis weight (g of sheet / sheet m 2 ) = water absorption amount per 1 g (g of water / sheet g, per unit weight) is calculated. The measurement is performed 5 times for each sample, and the average value is adopted.

[0051] Note that this measurement is carried out in accordance with JIS P 8111 method under the conditions of temperature 23 ± 1 °C and humidity 50 ± 2%. Also, the distilled water is maintained at 23 ± 1 °C.

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

[0053] (Paper thickness) The thickness (1 ply) of the paper towel sheet 1x according to the present 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, still 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 is inferior. If it exceeds 1400 μm, the water absorption of the paper towel sheet 1x becomes too high, absorbs the glue part 2, and the adhesiveness of the tail seal part 3 is inferior. Therefore, the tail part 3 tends to be easily peeled off during the production of the paper towel roll 1. The paper thickness is measured with a Peacock paper thickness gauge (manufactured by Ozaki Seisakusho Co., Ltd.) in a state of one sheet of the paper towel sheet 1x under a load of 37.85 gf / cm 2 and the measurement is repeated 10 times at different locations and the measured values are averaged to obtain the paper thickness.

[0054] (Embossing) The paper towel sheet 1x of the present embodiment is preferably embossed, and more preferably embossed by a roll winder. The shape of the embossing alone is not particularly limited, and examples include a circle, an ellipse, a rectangle, a square, a pattern, a polygon, a character, a line, a logo, etc. In order to obtain a paper towel sheet 1x having a high basis weight and excellent water absorption as in the present embodiment, a hexagonal shape is preferable.

[0055] In the embossing pattern, the depth of the embossing is preferably 0.07 mm or more and 1.8 mm or less, more preferably 0.2 mm or more and 1.2 mm or less, still more preferably 0.3 mm or more and 0.8 mm or less. If the depth of the embossing is less than 0.07 mm, the cosmetic property and water absorption of the paper towel sheet 1x are inferior, and the ease of use as a roll product is inferior. Further, if the depth of the embossing exceeds 1.80 mm, the adhesive area of the glue part 2 becomes small, and the tail seal part 3 tends to be easily peeled off during the production of the paper towel roll 1.

[0056] The depth of the emboss is measured using a microscope. As the microscope, the product named "One-shot 3D Measurement Macroscope VR-3100" manufactured by KEYENCE Corporation can be used. As the image observation, measurement, and image analysis software for the microscope, the product named "VR-H1A" can be used. Also, the measurement conditions are to measure under the conditions of a magnification of 12 times and a field of view area of 24 mm × 18 mm. The measurement magnification and the field of view area may be appropriately changed depending on the size of the emboss to be obtained.

[0057] Figure 3 shows the height profile on the X-Y plane by the microscope, and the height of the surface of the paper towel sheet 1x is represented by shading. The linear part where the shading in Figure 3 is different from the periphery indicates each emboss. The depth of the emboss is obtained by measuring the height difference of the above-mentioned emboss using the above microscope. The measurement is performed on the surface 1a side of the paper towel sheet 1x. Also, at the time of measurement, three circumferences of the paper towel sheet 1x are removed from the paper towel roll 1, and the fourth circumference of the paper towel sheet 1x is used for measurement in the form of a sheet. Also, when there are perforations, avoid them all for measurement.

[0058] First, draw a line segment AB as shown in Figure 3 to obtain the height profile of Figure 4. Note that the line segment AB may be drawn so as to cross the emboss. Also, the line segment AB is drawn in the roll width direction W (CD direction) of the paper towel sheet 1x. However, when the interval between the embosses is narrow, for example, 2 mm or less, and the height of the following convex part becomes low, the line segment may be drawn in an oblique direction or in the roll winding direction R. The height profile is the (measured) cross-sectional curve S1 representing the unevenness of the actual sample surface of the paper towel sheet 1x, but it also includes noise (fiber lumps on the surface of the paper towel sheet 1x, fibers growing in a whisker shape, or steep peaks caused by parts without fibers). When calculating the height difference of the unevenness, it is necessary to remove such noise peaks.

[0059] Therefore, the (measurement) cross-sectional curve S1 in FIG. 4 is used with the filter size of the weighted average radio button set to ±12 to obtain the smoothed cross-sectional curve S2 in FIG. 5. Note that smoothing using the filter of the weighted average radio button can be automatically obtained by using the above analysis software. Then, in the graph shown in FIG. 5, the average value of the maximum values of the vertical axes of the convex portion H1 of the graph and the convex portion H2 adjacent to the convex portion H1 is calculated, and the minimum value of the vertical axis in the concave portion D1 sandwiched between the convex portion H1 and the convex portion H2 is obtained. The numerical value obtained by subtracting the minimum value from the average value of the maximum values thus obtained is taken as the provisional embossing depth. Then, as shown in FIG. 5, the same measurement is performed for a total of two consecutive locations on the cross-sectional curve (a total of two consecutive locations, the concave portion D1 and the concave portion D2 sandwiched between the convex portion H3 and the convex portion H4) (at this point, two measurement results are obtained). Thereafter, the same measurement as above is performed at each position where the paper towel roll 1 is rotated three times by 90 degrees each in the roll winding direction R of the paper towel sheet 1x (the measurement positions in the roll winding direction R are a total of four locations), and the average value of a total of eight locations (2×4) is finally adopted as the embossing depth.

[0060] (DMDT and DCDT) For the two-ply paper towel sheet 1x, the dry machine direction (MD direction: roll winding direction R) tensile strength DMDT (Dry Machine Direction Tensile Strength) based on JIS P 8113 is preferably 8 N / 25 mm or more and 75 N / 25 mm or less, more preferably 13 N / 25 mm or more and 65 N / 25 mm or less, still more preferably 20 N / 25 mm or more and 50 N / 25 mm or less. Also, the dry cross direction (CD direction: roll width direction W) tensile strength DCDT (Dry Cross Direction Tensile Strength) is preferably 2 N / 25 mm or more and 50 N / 25 mm or less, more preferably 4 N / 25 mm or more and 40 N / 25 mm or less, still more preferably 5 N / 25 mm or more and 25 N / 25 mm or less. If the DMDT of the paper towel sheet 1x exceeds 75 N / 25 mm and / or the DCDT exceeds 50 N / 25 mm, the paper towel sheet 1x becomes too hard, the repulsion becomes strong when the paper towel sheet 1x is wound, and the tail seal portion 3 tends to be easily peeled off during the manufacture of the paper towel roll 1. If the DMDT of the paper towel sheet 10x is less than 8 N / 25 mm and / or the DCDT is less than 2 N / 25 mm, the basis weight of the paper towel sheet 1x becomes low and the water absorbency is poor.

[0061] (Flexural strength) The flexural strength 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, still more preferably 20 μN·m or more and 50 μN·m or less. If the flexural strength 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 becomes low and the water absorbency is poor. Also, if the flexural strength of the paper towel sheet 1x in the MD direction exceeds 130 μN·m, the paper towel sheet 1x becomes too hard, the repulsion of the paper towel sheet 1x becomes strong when wound into a roll, and the tail seal portion 3 tends to be easily peeled off during the manufacture of the paper towel roll 1.

[0062] The bending resistance of the paper towel sheet 1x in the MD direction can be measured using an L&W bending tester (manufactured by Lorentzen & Wettre) in accordance with the method described in ISO 2493. For a test piece of the paper towel sheet 1x with a width of 38 mm (CD direction) and a length of 100 mm (MD direction), when the bending angle is 15 degrees and the bending length (span of the specimen stage) is 10 mm, the measured value is taken as the bending resistance (load), and the bending resistance (μN·m) is obtained by the following calculation formula. If a test piece with a length of 100 mm cannot be collected, the length of the test piece can be shortened. Bending resistance (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 sheet and paper towel roll> As a method for manufacturing the paper towel sheet 1x and the paper towel roll 1, when the paper towel sheet 1x is a kitchen towel sheet containing synthetic fibers and pulp fibers, for example, (1) laminating pulp fibers on a predetermined spunbond nonwoven fabric for hydroentangling, (2) heat embossing treatment using matched steel, (3) perforation, and (4) roll winding can be carried out in this order. At this time, in the hydroentangling (1) of the manufacturing method, by hydroentangling pulp fibers with synthetic fibers, a nonwoven fabric containing synthetic fibers and pulp fibers is obtained. Regarding the method of hydroentangling, it is preferably carried out by the method described in Japanese Patent Application Laid-Open No. 2018-193634, for example.

[0064] As described above, the present invention has been described using embodiments. Needless to say, the technical scope of the present invention is not limited to the scope of the invention described in the above embodiments, and it is obvious to those skilled in the art that various changes or improvements can be made to the above embodiments. Also, it is obvious from the description of the claims that embodiments with such changes or improvements can also be included in the technical scope of the present invention.

Examples

[0065] Examples and comparative examples are given below to describe this embodiment more specifically.

[0066] (Examples 1 to 28, Comparative Examples 1 to 11) Through the processes of papermaking, creping, embossing, roll winding, and (tail seal glue coating), synthetic fibers and pulp fibers were used at the ratios (by weight) shown in Tables 1 and 2, and papermaking was carried out with the paper thickness and sheet length shown in Tables 1 and 2 to form an emboss, and single-ply paper towels of Examples 1 to 28 and Comparative Examples 1 to 11 were produced. Here, polypropylene resin fibers were used as the synthetic fibers. Also, as the glue, an aqueous PVA mixed solution of less than 10% by weight was used.

[0067] Using the obtained paper towels of Examples 1 to 28 and Comparative Examples 1 to 11, roll bodies of Examples 1 to 28 and Comparative Examples 1 to 11 having the roll diameter, roll length, roll width, roll weight, roll density, tail part length, peel strength, glue coating amount, and glue coating width shown in Tables 1 and 2 were produced. The following evaluations were carried out on the obtained paper towels and roll bodies. The results are shown in Tables 1 to 3.

[0068] 〔Evaluation method (physical property evaluation)〕 Paper thickness: Measured with a Peacock paper thickness gauge under a load of 37.85 gf / cm in the state of one sheet of paper towel sheet 1x. 2 Measured under load. Flexural stiffness: Flexural stiffness was measured in accordance with ISO 2493 using an L&W bending tester (manufactured by Lorentzen & Wettre). For a test piece 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 specimen stage) was 10 mm was taken as the bending resistance (load), and the flexural stiffness (μN·m) was obtained by the following calculation formula. Flexural stiffness (μN·m) = 60 × Bending resistance (mN) × Bending length 10 (mm) 2 ÷ (π × Bending angle 15 (°) × Specimen width 38 (mm)) DMDT, DCDT: The longitudinal and transverse tensile strengths during drying were measured based on JIS P9113. Water absorption: Cut the paper towel into a 75 mm × 75 mm square to prepare a sample piece, and measure its dry weight. Next, immerse this sample piece in distilled water for 2 minutes, and then in a container in a water vapor-saturated state, suspend it in a stretched state (100% RH) with one corner of the sample piece at the upper top and supporting and stretching the two adjacent corners to this top, leave it for 30 minutes, and then measure the weight after draining. For draining, cut a paper paper towel into 3 × 38 mm and use it. Then, convert the measured value to the water retention amount (g / g) per 1 g of the sample piece and the water retention amount (g / m 2 per square meter of the sample piece 2 ). . Embossing depth: The embossing depth is measured using a microscope. As the microscope, use the product named "One-shot 3D Measurement Macroscope VR-3100" manufactured by KEYENCE Corporation. As the image observation, measurement, and image analysis software for the microscope, the product named "VR-H1A" can be used. The measurement conditions are to measure under the conditions of a magnification of 12 times and a field of view area of 24 mm × 18 mm. Roll density: Obtained from (roll mass) ÷ (roll volume). The roll mass is the mass of the roll per 280 mm of roll width. The roll volume is [(the cross-sectional area of the outer diameter (winding diameter DR) part of the roll) - (the cross-sectional area of the core outer diameter part)] × roll width (converted to per 280 mm). Peel strength: The dry peel strength determined by a 180-degree peel test using a tensilon universal testing machine

[0069] 〔Evaluation method〕 For the manufactured paper towel sheet and paper towel roll, evaluation based on sensory evaluation or measured values was carried out for the difficulty of peeling of the tail seal during manufacturing, the ease of peeling of the tail seal during use, water absorption, ease of handling, and stickiness when wet with water.

[0070] Regarding the "difficulty of peeling of the tail seal during manufacturing", for 30 paper towel rolls after manufacturing, count the number of rolls with the tail seal peeled off and evaluate it in 5 grades. The evaluation criteria are as follows. ◎: The number of rolls with the tail seal partially or completely peeled off is 0 to 1 ○: 2 to 4 rolls with some or all of the tail seals peeled off △: 5 to 7 rolls with some or all of the tail seals peeled off ×: 8 to 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] "Ease of peeling the tail seal during use" was evaluated by 30 monitors through sensory evaluation of the ease of peeling the tail seal of the paper towel roll, and was evaluated in five levels according to the number of people who felt "difficult to peel" or "unable to peel". The evaluation criteria are as follows. ◎: The number of people who felt "difficult to peel" or "unable to peel" was 0 to 1 person ○: The number of people who felt "difficult to peel" or "unable to peel" was 2 to 4 people △: The number of people who felt "difficult to peel" or "unable to peel" was 5 to 7 people ×: The number of people who felt "difficult to peel" or "unable to peel" was 8 to 14 people ××: The number of people who felt "difficult to peel" or "unable to peel" was 15 or more people

[0072] "Water absorption" was evaluated in four levels by actually measuring the water absorption per unit area. The evaluation criteria are as follows. ◎: When it is 330 g / m 2 or more ○: When it is 270 g / m 2 or more and less than 330 g / m 2 △: When it is 230 g / m 2 or more and less than 270 g / m 2 ×: When it is less than 230 g / m 2

[0073] "Ease of holding" was evaluated by 30 monitors through sensory evaluation of the ease of holding the manufactured paper towel roll, and was evaluated in four levels according to the number of people who felt "difficult to hold". The evaluation criteria are as follows. ◎: The number of people who felt "difficult to hold" was 0 to 3 people​​​ ○: The number of people who felt it was "difficult to hold" was 4 - 6 people △: The number of people who felt it was "difficult to hold" was 7 - 10 people ×: The number of people who felt it was "difficult to hold" was 11 people or more

[0074] The "stickiness when wet with water" was evaluated by 30 monitors in terms of the stickiness when using a paper towel sheet wet with water, and was evaluated in four levels according to the number of people who felt "it has stickiness". The evaluation criteria are as follows ◎: The number of people who felt "it has stickiness" was 0 - 3 people ○: The number of people who felt "it has stickiness" was 4 - 6 people △: The number of people who felt "it has stickiness" was 7 - 10 people ×: The number of people who felt "it has stickiness" was 11 people or more

[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 absorbency, which can achieve both the difficulty of peeling of the tail seal during manufacturing and the ease of peeling of the paper towel during use and the low stickiness when wet with water, and can ensure easy handling

Explanation of Signs

[0079] 1 Paper towel roll 1a Surface 1b Back surface 1c Edge of the outermost circumference of the paper towel roll 1x Paper towel sheet 2 Tail seal group 3 Tail seal part 4 Tail part 200 Specimen 200a, 200d Corners 210 Band 220 Holder

Claims

1. A paper towel roll in which a 1-ply paper towel sheet containing synthetic fibers mainly composed of pulp fibers is wound in a roll shape, having a tail seal portion in which the tail portion of the paper towel sheet and the outermost peripheral surface of the paper towel roll are adhered by glue, The paper towel sheet has a basis weight of 40 g / m ２ or more and 150 g / m ２ or less. The water absorption is 210 g / m ２ or more and 520 g / m ２ or less, and wherein the application amount of the glue is 0.5 g or more and 5 g or less, The paper towel roll has a roll density of 0.05 g / cm ３ or more and 0.19 g / cm ３ or less, and a paper towel roll with a winding 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 thickness of the paper towel sheet is 200 μm or more and 1400 μm or less.

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

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

7. The paper towel roll according to any one of claims 1 to 6, 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. The paper towel roll according to any one of claims 1 to 7, 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.

9. The paper towel roll according to any one of claims 1 to 8, wherein the ratio of the synthetic fiber to the total basis weight of the paper towel sheet is 5% by weight or more and 50% by weight or less, and the ratio of the pulp fiber is 50% by weight or more and 95% by weight 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, the paper towel roll according to claim 9.

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