Kitchen towel roll

Abstract

To provide a kitchen towel roll having a low drying load in a TAD process and having excellent water absorption and touch.SOLUTION: A kitchen towel roll is formed by winding a kitchen towel sheet in a roll shape. The kitchen towel sheet is formed by laminating sheets into two plies in which at least a front ply is applied with an emboss pattern. A mass ratio of needle-leaved tree bleached craft pulp (NBKP) and wide-leaved tree bleached craft pulp (LBKP) contained in the kitchen towel sheet is 40 to 90 mass%: 10 to 60 mass%. An amount of water absorption per unit area of the kitchen towel sheet is equal to or greater than 290 g / m2 and equal to or less than 610 g / m2.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to kitchen towel rolls containing particular pulp. [Background technology]

[0002] In recent years, various kitchen towel sheets and kitchen towel rolls made by rolling up sheets have been developed and sold.

[0003] For kitchen towels, absorbency and a firm feel when used are important, and for regular base paper, papermaking techniques have been developed to increase the basis weight to improve absorbency and to increase the strength of the base paper to give it a firm feel.

[0004] On the other hand, the so-called TAD (Through Air Drying) papermaking technology (hereinafter also referred to as the "TAD papermaking method"), which uses through-air drying, can produce base paper with high water absorption and bulk, making it excellent as base paper for kitchen towel rolls.

[0005] As a prior art document relating to kitchen towel rolls, for example, Patent Document 1 describes a kitchen towel roll in which sheets with embossed patterns are glued together and laminated into two plies, and the resulting kitchen towel sheet is wound into a roll. The kitchen towel sheet has a concave-convex pattern derived from the papermaking process that is different from the embossed pattern, and the basis weight of the two plies is 30 g / m. 2 More than 54g / m 2 The following is a paper thickness of 1.3 mm / 10 sheets or more and 5 mm / 10 sheets or less, 2 ply, 1 m 2 The kitchen towel roll is characterized by having a water absorption per roll of 220 g to 600 g, a roll length of 14 m to 44 m, and a roll diameter of 110 mm to 189 mm. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2022-116768 Summary of the Invention [Problem to be solved by the invention]

[0007] However, TAD has the problem of higher drying load during production than a regular dry crepe machine, resulting in higher production costs.

[0008] Possible methods for reducing the drying load during TAD production include reducing the basis weight, slowing down the speed, improving drainage of the raw pulp, and increasing dehydration before the TAD part.

[0009] However, lowering the basis weight impairs the quality of the final product (absorbency, strength, and texture), and slowing the speed also reduces productivity, resulting in increased costs.

[0010] Furthermore, if the dehydration before the TAD part is increased, the water absorbency may be slightly reduced. From the above, it can be said that the most efficient method for reducing the drying load is to improve the drainage of raw pulp.

[0011] One way to improve drainage of raw pulp is to increase the ratio of softwood pulp in the raw material, but if the ratio of softwood pulp is too high, the strength will be too high, resulting in a stiff feel.

[0012] Conversely, if the ratio of softwood pulp is too low (the ratio of hardwood pulp is high), stronger beating is required to ensure strength. However, stronger beating increases the amount of fine fibers, which makes it harder for water to drain and increases the drying load.

[0013] The present invention has been made in view of the above circumstances, and aims to provide a kitchen towel roll that has a low drying load in the TAD process and is excellent in water absorbency and feel. [Means for solving the problem]

[0014] After extensive research, the inventors discovered that in a kitchen towel roll made by laminating two plies of a kitchen towel sheet, at least the front ply of which has an embossed pattern, and winding the resulting sheet into a roll, by specifying a mass ratio of softwood bleached kraft pulp (NBKP) to hardwood bleached kraft pulp (LBKP) in the kitchen towel sheet within a predetermined range and further specifying a water absorption per unit area of ​​the kitchen towel sheet within a predetermined numerical range, a kitchen towel roll can be produced that has a low drying load in the TAD process and excellent water absorbency and feel, thereby solving the above-mentioned problems and leading to the completion of the present invention.

[0015] (1) The first aspect of the present invention is a kitchen towel roll in which a kitchen towel sheet is formed by laminating two plies of sheets each having an embossed pattern on at least the front ply, the kitchen towel sheet being wound into a roll, the mass ratio of softwood bleached kraft pulp (NBKP) to hardwood bleached kraft pulp (LBKP) contained in the kitchen towel sheet being 40-90% by mass:10-60% by mass, and the water absorption per unit area of ​​the kitchen towel sheet being 290 g / m 2 More than 610g / m 2 A kitchen towel roll characterized by the following:

[0016] (2) A second aspect of the present invention is the kitchen towel roll described in (1), characterized in that the kitchen towel sheet has an uneven pattern resulting from the papermaking process that is different from the embossed pattern.

[0017] (3) A third aspect of the present invention is the kitchen towel roll according to (1), wherein the basis weight of the kitchen towel sheet per two plies is 30 g / m 2 More than 54g / m 2 It is characterized by the following:

[0018] (4) A fourth aspect of the present invention is the kitchen towel roll according to (1), characterized in that the ratio (DMDT / DCDT) of the tensile strength in the MD direction (DMDT) of the kitchen towel sheet in the dry state according to JIS P 8113 to the tensile strength in the CD direction (DCDT) of the kitchen towel sheet in the dry state according to JIS P 8113 is 0.8 or more and 1.4 or less.

[0019] (5) A fifth aspect of the present invention is the kitchen towel roll according to (1), wherein the specific volume of the kitchen towel sheet is 7 cm 3 / g or more 23cm 3 / g or less.

[0020] (6) A sixth aspect of the present invention is the kitchen towel roll described in (1), characterized in that the GMT of the kitchen towel sheet, which is the square root of the product of the tensile strength in the MD direction (DMDT) when dry based on JIS P 8113 and the tensile strength in the CD direction (DCDT) when dry based on JIS P 8113, is 480 cN / 25 mm or more and 1450 cN / 25 mm or less.

[0021] (7) A seventh aspect of the present invention is the kitchen towel roll according to (1), characterized in that the embossing pattern includes radial embossing and closed-ring structure embossing.

[0022] (8) The eighth aspect of the present invention is a kitchen towel roll according to (1), characterized in that the embossed pattern includes linear embossed portions, and the proportion of the linear embossed portions included in the embossed pattern is 20% or more.

[0023] (9) The ninth aspect of the present invention is the kitchen towel roll according to (7), characterized in that the radial embossments and the closed ring structure embossments are alternately arranged at equal intervals.

[0024] (10) The tenth aspect of the present invention is the kitchen towel roll described in (7), characterized in that for each of the radial embossing and the closed ring structure embossing, the arrangement angle of adjacent identical patterns is 20° or more and 80° or less relative to the CD direction of the kitchen towel sheet. [Effects of the Invention]

[0025] According to the present invention, it is possible to provide a kitchen towel roll that has a low drying load in the TAD process and is excellent in water absorbency and feel. [Brief explanation of the drawings]

[0026] [Figure 1] 1 is a perspective view of a kitchen towel roll according to an embodiment of the present invention. [Figure 2] FIG. 1 is a diagram showing an example of an embossing pattern in a kitchen towel roll of the present invention. [Figure 3] FIG. 1 is a diagram showing an example of radial embossing and closed-ring structure embossing included in the embossing pattern of the kitchen towel roll of the present invention. [Figure 4] FIG. 1 is a diagram showing a method for measuring the arrangement angle of the embossed pattern in the kitchen towel roll of the present invention. [Figure 5] FIG. 1 is a diagram showing a method for measuring the water absorption of the kitchen towel sheet of the present invention. [Figure 6] 1 is a diagram showing a part of the papermaking process for the kitchen towel sheet of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0027] Hereinafter, a mode for carrying out the present invention (hereinafter simply referred to as "the present embodiment") will be described in detail. The following present embodiment is an example for explaining the present invention, and is not intended to limit the present invention to the following content. The present invention can be carried out by appropriately modifying it within the scope of its gist.

[0028] The MD direction of the kitchen towel sheet is the machine direction in which the kitchen towel sheet is made, and the CD direction is the direction perpendicular to the MD direction (cross direction). The product ply refers to the number of plies in a kitchen towel sheet. For example, if two kitchen towel sheets are stacked on top of each other and then wound up to make a kitchen towel roll, the product ply will be two plies.

[0029] <Kitchen towel roll> Fig. 1 is a perspective view of a kitchen towel roll 1 according to one embodiment of the present invention. As shown in Fig. 1, the kitchen towel roll 1 according to this embodiment is a kitchen towel sheet 1x made by laminating two plies of sheets each having an embossed pattern 10 on at least the front ply, and wound into a roll. Preferably, the kitchen towel sheet 1x has perforations formed across the width of the roll at approximately equal intervals in the winding direction of the roll (not shown). As shown in Figure 1, the surface of the kitchen towel sheet 1x facing the outside of the roll is referred to as surface 1a (surface of the kitchen towel sheet 1x), and the surface facing the center of the roll is referred to as back surface 1b (back surface of the kitchen towel sheet 1x). The edge of the kitchen towel sheet 1x is referred to as the outermost edge 1e of the kitchen towel roll 1.

[0030] The kitchen towel roll 1 can be used, for example, as a roll of kitchen paper (sometimes called paper towel or cooking paper) used in home kitchens, restaurant kitchens, etc. to wipe away moisture or oil and remove dirt, as well as other rolls of sanitary paper.

[0031] (winding length and winding diameter) The lower limit of the roll length of the kitchen towel roll 1 is preferably 18 m or more, more preferably 20 m or more, and even more preferably 24 m or more, and the upper limit is preferably 45 m or less, more preferably 40 m or less, and even more preferably 35 m or less. If the roll length is less than 18 m, the basis weight of the kitchen towel sheet 1x must be increased to achieve a certain roll diameter DR, resulting in poor hand feel.If the roll length is more than 45 m, the basis weight of the kitchen towel sheet 1x must be decreased to achieve a certain roll diameter DR, resulting in poor water absorbency.

[0032] The roll length is measured as follows: First, measure the length of 10 kitchen towel sheets 1x between the perforations on kitchen towel roll 1. Next, measure the number of sheets on kitchen towel roll 1, and calculate the roll length proportionally from the length of 10 sheets and the number of sheets. For example, if the length of 10 sheets is 1.80 m and there are 150 sheets, the roll length is 1.80 m x (150 / 10) = 27 m. Note that if kitchen towel roll 1 does not have perforations, measure the roll length.

[0033] The lower limit of the roll diameter DR of the kitchen towel roll 1 according to this embodiment is preferably 127 mm or more, more preferably 135 mm or more, and even more preferably 140 mm or more, and the upper limit is preferably 175 mm or less, more preferably 165 mm or less, and even more preferably 157 mm or less. If the roll diameter DR is less than 127 mm, the basis weight of the kitchen towel sheet 1x will be low, resulting in poor absorbency. If the roll diameter DR is more than 175 mm, the basis weight of the kitchen towel sheet 1x will be high, resulting in poor feel.

[0034] The roll diameter DR is measured using a diameter rule manufactured by Muratec KDS Co., Ltd. Three kitchen towel rolls 1 are measured and the measurement results are averaged.

[0035] (roll width and roll mass) The roll width of the kitchen towel roll 1 has a lower limit of preferably 150 mm or more, more preferably 200 mm or more, and even more preferably 250 mm or more, and an upper limit of preferably 380 mm or less, more preferably 340 mm or less, and even more preferably 300 mm or less. If the roll width is less than 150 mm, the kitchen towel sheet 1x will be small and will have poor absorbency, whereas if the roll width is more than 380 mm, the kitchen towel sheet 1x will be too large and will be less user-friendly as a product.

[0036] The lower limit of the roll mass of the kitchen towel roll 1 is preferably 200 g or more, more preferably 240 g or more, and even more preferably 260 g or more, and the upper limit is preferably 550 g or less, more preferably 490 g or less, and even more preferably 450 g or less. If the roll mass is less than 200 g, the basis weight of the kitchen towel sheet 1x will be low, resulting in poor absorbency.If the roll mass is more than 550 g, the basis weight of the kitchen towel sheet 1x will be high, resulting in poor feel.

[0037] The roll mass is the mass per 280mm of roll width, excluding the paper tube 2 (core) of the kitchen towel roll 1. If the roll width is not 280mm, convert it to the mass per 280mm by proportional calculation.

[0038] (roll density) The roll density of the kitchen towel roll 1 according to this embodiment has a lower limit of 0.04 g / cm 3 It is preferable that the concentration is 0.05 g / cm or more. 3 More preferably, it is 0.06 g / cm or more. 3 The upper limit is more preferably 0.13 g / cm. 3 Preferably, it is 0.11 g / cm or less. 3 More preferably, it is 0.09 g / cm or less. 3It is more preferable that: Roll density is 0.04g / cm 3 If the roll density is less than 0.13 g / cm, the thickness of the kitchen towel sheet will be too thick and the feel will be poor. 3 If it exceeds this, the paper thickness of the kitchen towel sheet 1x will be low and the absorbency will be poor.

[0039] Roll density is expressed as (roll mass) ÷ (roll volume). Roll mass is the mass of a kitchen towel roll 1 per 280 mm of roll width. Roll volume is expressed as [{cross-sectional area of ​​the roll's outer diameter (winding diameter DR)} - (cross-sectional area of ​​the paper core's outer diameter DI)] × roll width (converted to per 280 mm). For example, if the roll mass (excluding the paper core) per 280 mm of roll width is 382 g, the winding diameter DR is 150 mm, and the paper core's outer diameter DI is 39 mm, then roll density = 382 g ÷ [{3.14 × (150 mm ÷ 2 ÷ 10) 2 -3.14×(39mm÷2÷10) 2}×(280mm÷10)]=0.08g / cm 3 This becomes:

[0040] (winding density) The winding density of the kitchen towel roll 1 according to this embodiment has a lower limit of 0.20 m / cm 2 It is preferable that the thickness is 0.24 m / cm or more. 2 More preferably, it is 0.30 m / cm or more. 2 The upper limit is more preferably 0.56 m / cm. 2 Preferably, it is 0.50 m / cm or less. 2 More preferably, it is 0.45 m / cm or less. 2 It is more preferable that: Winding density is 0.20m / cm 2 If the winding density is less than 0.56 m / cm, the basis weight of the kitchen towel sheet 1x will be high, resulting in an inferior feel. 2 If it exceeds this value, the basis weight of the kitchen towel sheet 1x will be low, resulting in poor absorbency.

[0041] The winding density is expressed as (winding length x number of plies) ÷ (cross-sectional area of ​​the roll). The cross-sectional area of ​​the roll is expressed as {cross-sectional area of ​​the roll outer diameter (winding diameter DR) - (cross-sectional area of ​​the cardboard core outer diameter DI)}. For example, in the case of a winding length of 27 m, 2 plies, a winding diameter DR of 150 mm, and a cardboard core outer diameter DI of 39 mm, the winding density = (27 m x 2) ÷ {3.14 x (150 mm ÷ 2 ÷ 10) 2 -3.14×(39mm÷2÷10) 2}=0.33m / cm 2 This becomes:

[0042] (Paper tube outer diameter) The lower limit of the paper tube outer diameter DI, which is the outer diameter of the paper tube 2 that forms the core of the kitchen towel roll 1 of the present invention, is preferably 28 mm or more, more preferably 33 mm or more, and even more preferably 40 mm or more, and the upper limit is preferably 58 mm or less, more preferably 53 mm or less, and even more preferably 46 mm or less. If the paper tube outer diameter DI is less than 28 mm, the resulting reel diameter DR will be small, so to maintain a certain range of reel diameter DR, the basis weight of the kitchen towel sheet 1x must be increased instead, resulting in an inferior feel to the touch of the kitchen towel sheet 1x. If the paper tube outer diameter DI is more than 58 mm, the resulting reel diameter DR will be large, so to maintain a certain range of reel diameter DR, the basis weight of the kitchen towel sheet 1x must be decreased instead, resulting in inferior water absorbency.

[0043] The outer diameter DI of the paper core is measured using a diameter rule manufactured by Muratec KDS Co., Ltd. Three kitchen towel rolls 1 are measured and the measurement results are averaged. If the core does not have a paper core 2, the outer diameter of the hollow core part is measured.

[0044] The paper tube 2 is made of a plurality of layers of base paper, preferably two layers. The pulp fiber contained in the base paper is preferably bleached kraft pulp (BKP). The BKP content in the base paper is preferably 50% by mass or more, more preferably 70% by mass or more, and even more preferably 90% by mass or more. In this case, the BKP preferably contains bleached hardwood kraft pulp (LBKP), and the LBKP content is preferably 50% by mass or more, more preferably 70% by mass or more, and even more preferably 90% by mass or more.

[0045] <Kitchen towel sheet> The kitchen towel sheet 1x according to this embodiment preferably contains wet pulp. The wet pulp content is preferably 50% or more. If the wet pulp content is less than 50%, the kitchen towel sheet 1x will have poor water absorbency. There is no upper limit for the wet pulp content, but if it is too high, the strength of the kitchen towel sheet 1x will tend to increase, which may result in a poor feel. The wet pulp content in the kitchen towel sheet 1x is more preferably 65% ​​or more, and even more preferably 80% or more.

[0046] Pulp includes softwood bleached kraft pulp (NBKP) and hardwood bleached kraft pulp (LBKP). The mass ratio of softwood bleached kraft pulp (NBKP) to hardwood bleached kraft pulp (LBKP) in the kitchen towel sheet 1x is preferably 40-90% by mass:10-60% by mass. If the mass ratio of NBKP is too high, the feel of the kitchen towel sheet 1x will be poor. If the mass ratio of LBKP is too high, the drying load during production of the kitchen towel sheet 1x will be high. The mass ratio of softwood bleached kraft pulp (NBKP) to hardwood bleached kraft pulp (LBKP) in the kitchen towel sheet 1x is preferably NBKP:LBKP=50-90% by mass:10-50% by mass, more preferably NBKP:LBKP=60-80% by mass:20-40% by mass.

[0047] As for the pulp treatment, it is preferable that NBKP is beaten and LBKP is not beaten. Furthermore, other pulps may be contained in an amount of preferably 20% by mass, more preferably 10% by mass, even more preferably 5% by mass, and most preferably 0% by mass, based on the ratio of NBKP to LBKP.

[0048] (Basic weight) The basis weight per two plies of the kitchen towel sheet 1x according to this embodiment is 30 g / m 2 More than 54g / m 2 The basis weight per two plies is 30 g / m 2 If the thickness is less than 54 g / m², the kitchen towel sheet 1x will have poor absorbency. 2 Above this, 1x kitchen towel sheet will feel inferior. The minimum basis weight for two plies of a kitchen towel sheet is 36 g / m 2 It is preferable that the weight is 38 g / m or more. 2 The upper limit is more preferably 48 g / m or more. 2 Preferably, it is 45 g / m or less. 2 More preferably, it is:

[0049] In addition, the minimum basis weight per ply of a kitchen towel sheet is 15 g / m 2 It is preferable that the weight is 18 g / m or more. 2 More preferably, it is 19 g / m or more. 2 The upper limit is more preferably 27 g / m or more. 2 Preferably, it is 24 g / m or less. 2 More preferably, it is 22.5 g / m or less. 2 It is more preferable that the basis weight per ply is 15 g / m or less. 2 If the ply weight is less than 27 g / m, the kitchen towel sheet 1x will have poor absorbency. 2 Above this, 1x kitchen towel sheet will feel inferior. The basis weight of the kitchen towel sheet 1x can be measured based on JIS P 8124.

[0050] (paper thickness) The lower limit of the paper thickness per two plies of the kitchen towel sheet 1x is preferably 0.35 mm or more, more preferably 0.40 mm or more, and even more preferably 0.45 mm or more. The upper limit is preferably 0.80 mm or less, more preferably 0.75 mm or less, and even more preferably 0.70 mm or less. If the paper thickness per two plies is less than 0.35 mm, the kitchen towel sheet 1x will have poor water absorbency. If the paper thickness per two plies is more than 0.80 mm, the kitchen towel sheet 1x will have poor feel.

[0051] The paper thickness per two plies can be measured using a thickness gauge (a dial thickness gauge "PEACOCK" manufactured by Ozaki Seisakusho Co., Ltd.). The measurement conditions are a measurement load of 37.85 gf / cm 2 The gauge head has a diameter of 30 mm. Place the sample between the gauge head and the measuring table, and read the gauge when the gauge head is lowered at a speed of 1 mm per second or less. The sample is a kitchen towel sheet, 10 plies in length (5 sets of 2 plies = 10 plies), and the measurements are proportionally calculated to obtain the value per 2 plies. The measurement is also repeated 10 times at different locations, and the average of the measurement results is used as the final paper thickness per 2 plies.

[0052] (seat length) The sheet length between perforations (the length of the kitchen towel sheet 1x in the direction of winding the roll) has a lower limit of preferably 100 mm or more, more preferably 130 mm or more, and even more preferably 150 mm or more, and an upper limit of preferably 250 mm or less, more preferably 230 mm or less, and even more preferably 210 mm or less. If the sheet length is less than 100 mm, the kitchen towel sheet 1x will have poor absorbency, and if the sheet length is more than 250 mm, the kitchen towel sheet 1x will be too long and will be less user-friendly as a product.

[0053] (specific volume) The specific volume of one kitchen towel sheet is 7cm 3 / g or more 23cm 3 / g or less. 3 If the specific volume is less than 23 cm3, the kitchen towel sheet 1x will have poor absorbency. 3 If the value exceeds / g, the feel of one kitchen towel sheet will be poor. The specific volume of one kitchen towel sheet is limited to 9 cm 3 / g or more is more preferable, and 12cm 3 / g or more is more preferable. The upper limit is 20 cm 3 / g or less is more preferable, and 17cm 3 The specific volume is calculated by dividing the paper thickness per ply of 1x kitchen towel sheet by the basis weight per ply (the paper thickness per product ply is the basis weight per product ply), and then calculating the volume (cm) per unit (g). 3 )

[0054] (DMDT, DCDT and GMT) The dry machine direction tensile strength (DMDT) of the kitchen towel sheet 1x in the dry state according to JIS P 8113 is preferably 600 cN / 25 mm or more, more preferably 700 cN / 25 mm or more, and even more preferably 800 cN / 25 mm or more, and the upper limit is preferably 1500 cN / 25 mm or less, more preferably 1400 cN / 25 mm or less, and even more preferably 1300 cN / 25 mm or less. If the DMDT is less than 600cN / 25mm, the resulting kitchen towel sheet 1x will have a low basis weight and poor absorbency. If the DMDT is more than 1500cN / 25mm, the resulting kitchen towel sheet 1x will have a high basis weight and poor feel. Alternatively, the beating will be too strong, making the kitchen towel sheet 1x stiff and poor feel.

[0055] The dry cross direction tensile strength (DCDT) of the kitchen towel sheet 1x in the dry state according to JIS P 8113 is preferably 400 cN / 25 mm or more, more preferably 600 cN / 25 mm or more, and even more preferably 750 cN / 25 mm or more, and the upper limit is preferably 1400 cN / 25 mm or less, more preferably 1300 cN / 25 mm or less, and even more preferably 1150 cN / 25 mm or less. If the DCDT is less than 400cN / 25mm, the resulting kitchen towel sheet 1x will have a low basis weight and poor absorbency. If the DCDT is more than 1400cN / 25mm, the resulting kitchen towel sheet 1x will have a high basis weight and poor feel. Alternatively, the beating will be too strong, making the kitchen towel sheet 1x stiff and poor feel.

[0056] Furthermore, the ratio of DMDT to DCDT (DMDT / DCDT) is preferably 0.8 or more and 1.4 or less. If the ratio is less than 0.8, the basis weight of the kitchen towel sheet 1x will be low, resulting in poor absorbency. If the ratio is more than 1.4, the basis weight of the kitchen towel sheet 1x will be high, resulting in poor feel. The lower limit of the ratio of DMDT to DCDT (DMDT / DCDT) is preferably 0.9 or more, and more preferably 1.0 or more, and the upper limit is preferably 1.3 or less, and even more preferably 1.2 or less.

[0057] The GMT, which is the square root of the product of DMDT and DCDT, is preferably 480 cN / 25 mm or more and 1450 cN / 25 mm or less. If the GMT is less than 480 cN / 25 mm, the resulting kitchen towel sheet 1x will have a low basis weight and poor absorbency. If the GMT is more than 1450 cN / 25 mm, the resulting kitchen towel sheet 1x will have a high basis weight and poor feel. Alternatively, the beating will be too strong, making the kitchen towel sheet 1x stiff and poor feel. The lower limit of the GMT is more preferably 640 cN / 25 mm or more, and even more preferably 770 cN / 25 mm or more, and the upper limit is more preferably 1350 cN / 25 mm or less, and even more preferably 1250 cN / 25 mm or less.

[0058] The DMDT and DCDT of one kitchen towel sheet are measured in accordance with JIS P 8113. The ratio (DMDT / DCDT) and the square root of the product (GMT) are calculated from the measured DMDT and DCDT values. Note that both DMDT and DCDT are measured when one kitchen towel sheet is in a two-ply state.

[0059] (WMDT and WCDT) The wet machine direction tensile strength (WMDT) of the kitchen towel sheet 1x according to the old JIS S 3104 is preferably 200 cN / 25 mm or more, more preferably 230 cN / 25 mm or more, and even more preferably 260 cN / 25 mm or more, and the upper limit is preferably 430 cN / 25 mm or less, more preferably 380 cN / 25 mm or less, and even more preferably 340 cN / 25 mm or less. If the WMDT is less than 200cN / 25mm, the resulting kitchen towel sheet 1x will have a low basis weight and poor absorbency, while if the WMDT is more than 430cN / 25mm, the resulting kitchen towel sheet 1x will have a high basis weight and poor feel.

[0060] Furthermore, the wet cross direction tensile strength (WCDT) of the kitchen towel sheet 1x according to the old JIS S 3104 is preferably 160 cN / 25 mm or more in the lower limit, more preferably 190 cN / 25 mm or more, and even more preferably 220 cN / 25 mm or more in the upper limit, preferably 370 cN / 25 mm or less, more preferably 330 cN / 25 mm or less, and even more preferably 300 cN / 25 mm or less. If the WCDT is less than 160cN / 25mm, the resulting kitchen towel sheet 1x will have a low basis weight and poor absorbency, while if the WCDT is more than 370cN / 25mm, the resulting kitchen towel sheet 1x will have a high basis weight and poor feel. The WMDT and WCDT of one kitchen towel sheet are measured in accordance with the old JIS S 3104.

[0061] (growth rate) The lower limit of the MD elongation of the kitchen towel sheet 1x is preferably 10% or more, more preferably 12% or more, and even more preferably 13% or more, and the upper limit is preferably 22% or less, more preferably 20% or less, and even more preferably 18% or less. If the MD elongation is less than 10%, the kitchen towel sheet 1x will have a low basis weight and poor absorbency. If the MD elongation is more than 22%, the kitchen towel sheet 1x will have a high basis weight and poor feel. The MD elongation of the kitchen towel sheet 1x is measured in accordance with JIS P 8113.

[0062] (Embossed) The kitchen towel roll 1 (kitchen towel sheet 1x) of this embodiment is embossed and has an embossed pattern 10. Furthermore, the kitchen towel sheet 1x of the present invention is formed by laminating two plies after embossing at least the front ply. When laminating two plies, it is preferable to use, for example, ply bond glue to apply the glue and perform the bonding process. By bonding the plies together in this way to form two plies, the plies are strongly bonded together, and the kitchen towel sheet 1x is less likely to tear or peel off even when wet. Furthermore, water may be used instead of ply bond glue, or a mixture of glue and water may be used.

[0063] The ply on the front surface 1a of the kitchen towel sheet 1x preferably has an embossed pattern 10. By providing the embossed pattern 10 on the front surface 1a, glue can be applied to the embossed portion and the two plies can be laminated together. The sheet on the back surface 1b may have (or have) an embossed pattern, but it is preferable that it does not have (or do not have). By not having an embossed pattern on the back surface 1b, the kitchen towel sheet 1x (kitchen towel roll 1) can have an excellent texture.

[0064] 2 and 3 are diagrams showing an example of an embossed pattern 10 in the kitchen towel roll of this embodiment. The embossed pattern 10 preferably includes radial embossments 11 and closed-ring structure embossments 12. Without the radial embossments 11, the kitchen towel sheet 1x will be less user-friendly as a product. Without the closed-ring structure embossments 12, the kitchen towel sheet 1x will have poor water absorbency. It is also preferable that the radial embossments 11 and the closed-ring structure embossments 12 are alternately arranged at equal intervals. By alternately arranging the radial embossments 11 and the closed-ring structure embossments 12 at equal intervals, the kitchen towel sheet 1x can be made to have excellent water absorbency and be easy to use as a product.

[0065] The overall shape of the radial embossments 11 is not particularly limited, but it is preferable that the embossments have a linear shape extending from the center to the outside or a plurality of linear embossments. When the embossing pattern 10 includes the radial embossments 11, the kitchen towel sheet 1x becomes easy to use as a product. Like the radial embossments 11, the overall shape of the closed-ring structure embossments 12 is not particularly limited, but it is preferable that the closed-ring structure embossments include a linear or geometric embossment provided in the center and a geometric embossment that surrounds the central embossment to form a closed ring. When the embossed pattern 10 includes the closed-ring structure embossments 12, water is retained inside the embossments, improving the water absorbency of the kitchen towel sheet 1x.

[0066] The size of the embossed pattern 10, which includes one radial embossment 11 and one closed-ring structure embossment 12, has a lower limit of 16 cm 2 Preferably, it is 28cm or more. 2 More preferably, it is 45cm or more. 2 The upper limit is more preferably 250 cm or more. 2 Preferably less than 180cm 2 It is more preferable that it is less than 110cm 2 It is more preferable that: Embossing pattern 10 is 16cm in size 2 If the size of the embossed pattern 10 is less than 250 cm, the embossed pattern 10 is too small, and the kitchen towel sheet 1x has poor water absorbency. 2 If it exceeds this, the embossed pattern 10 will be too large and the kitchen towel sheet 1x will have poor absorbency. The size of the embossed pattern 10 is determined by calculating the area of ​​a rectangle E that includes (circumscribes) one embossed pattern 10 as shown in Fig. 3. The sizes of the long and short sides of this rectangle E can be changed as appropriate depending on the size of the embossed pattern 10 (radial embossments 11 and closed-ring structure embossments 12).

[0067] Furthermore, for each of the radial embossments 11 and the closed-ring structure embossments 12, the arrangement angle of adjacent identical patterns (hereinafter also referred to as the "arrangement angle of the embossment pattern 10") is preferably 20° or more and 80° or less relative to the CD direction of the kitchen towel sheet 1x. If the arrangement angle of the embossment pattern 10 is less than 20° or more than 80°, the kitchen towel sheet 1x is likely to wrinkle during processing. The lower limit of the arrangement angle is more preferably 25° or more, and even more preferably 30° or more. The upper limit of the arrangement angle is more preferably 70° or less, and even more preferably 60° or less.

[0068] The arrangement angle of the embossed pattern 10 is measured by the following method. (1) Select one embossment to be used as the measurement standard and determine the reference point of this embossment. For example, as shown in Figure 4, the kitchen towel sheet 1x is placed so that the MD direction (Y direction) is vertical and the CD direction (X direction) is horizontal. Then, an arbitrary closed-ring structure embossment 12A (hereinafter referred to as "embossment 12A") in the center of the kitchen towel sheet 1x is selected, and its center point is set as reference point 12a. (2) Two embossments adjacent to the reference embossment on the left and right in the CD direction are identified, and measurement points for these embossments are determined. As shown in Figure 4, a straight line passing through reference point 12a and parallel to the CD direction is drawn, and this is designated as reference line 12x. The left closed-ring structure embossment and the right closed-ring structure embossment, which are located above reference line 12x and closest to reference point 12a in the CD direction, are designated as 12B and 12C, respectively, and their center points are designated as measurement points 12b and 12c. (3) Draw an auxiliary line passing through the reference point and the measurement point, and measure the angle between the reference line and the auxiliary line. As shown in Figure 4, an auxiliary line 12y passing through reference point 12a and measurement point 12b, and an auxiliary line 12z passing through reference point 12a and measurement point c are drawn. Then, the angle θ1 formed by reference line 12x and auxiliary line 12y, and the angle θ2 formed by reference line 12x and auxiliary line 12z are measured with a protractor and are defined as the arrangement angles. In Figure 4, θ1 is 35° and θ2 is 55°. Note that when θ exceeds 90°, the arrangement angle is defined as the angle obtained by subtracting θ from 180°. For example, when θ is 120°, the angle is defined as 60° (= 180° - 120°).

[0069] Furthermore, the embossed pattern 10 preferably includes linear embossed portions 100, and the proportion of linear embossed portions 100 included in the embossed pattern 10 is preferably 20% or more. If the proportion is less than 20%, the embossed pattern 10 will not contribute to improving the feel and water absorbency, and the kitchen towel sheet 1x will have poor feel and water absorbency. The proportion of the linear embossed portions 100 contained in the embossed pattern 10 is more preferably 50% or more, and even more preferably 90% or more.

[0070] In this case, the linear embossed portion 100 refers to an embossment having a thickness of 0.1 mm to 4 mm and a length of 5 mm or more. The proportion of the linear embossed portion 100 is determined as follows. First, any 100mm x 100mm area on the surface of the kitchen towel sheet 1x with the embossed pattern 10 is divided into 10mm squares. Then, the proportion of the linear embossed portion 100 is calculated using the following formula. Note that if a single square contains both linear embossing and dot embossing, the square with the larger embossing percentage is used. (Number of squares containing linear embossing / Number of squares containing any embossing) x 100 = Percentage of linear embossing in 100 (%)

[0071] Furthermore, there is no particular restriction on whether the back surface 1b of the kitchen towel sheet 1x has an embossed pattern 10, as long as it has a pattern of protrusions and recesses resulting from the papermaking process that is different from the embossed pattern 10 described below. Nested embossing or pin-to-pin embossing may be applied, or no embossing may be applied, but nested embossing or no embossing is preferred, and no embossing is more preferred.

[0072] (Water absorption) In the present invention, the water absorption per unit area of ​​a kitchen towel sheet 1x is 290 g / m 2 More than 610g / m 2 The water absorption per unit area is 290g / m 2 If the thickness is less than 610g / m, the kitchen towel sheet 1x will have poor absorbency. 2 If it exceeds this value, the basis weight of one kitchen towel sheet will be high, resulting in an inferior feel. The minimum water absorption per unit area of ​​one kitchen towel sheet is 330 g / m 2 It is preferable that the weight is 380 g / m or more. 2 The upper limit is more preferably 550 g / m or more. 2 Preferably, it is 500 g / m or less. 2 More preferably, it is:

[0073] The water absorption per unit mass of the kitchen towel sheet 1x is preferably 8.0 g / g or more, more preferably 8.5 g / g or more, and even more preferably 9.0 g / g or more, and more preferably 14 g / g or less, and even more preferably 13 g / g or less. If the water absorption per unit mass is less than 8.0 g / g, the kitchen towel sheet 1x will have poor water absorbency.

[0074] The method for measuring the water absorption of each kitchen towel sheet 1x will be described below with reference to FIG. First, a two-ply kitchen towel sheet 1x is taken and cut using a square template with each side measuring 7.6 cm to prepare a rectangular test piece 20 with each side measuring 7.6 cm. The mass of the test piece 20 before water absorption is measured using an electronic balance. The test piece 20 is set in a holder 21 (a jig that fixes three points of the test piece, made of a metal that does not absorb water).

[0075] Next, distilled water is poured into a commercially available tray to a depth of 2 cm, and the test piece 20 set in the holder 21 is immersed in the distilled water for 2 minutes. After immersion for 2 minutes, the test piece 20 is removed from the distilled water together with the holder 21, and the holder 21 and test piece 20 are hung from a rod placed in an empty water tank with the corner 20a facing up, and the lid of the water tank is closed and left for 5 minutes.

[0076] Thereafter, the holder 21 and the test piece 20 are taken out of the water tank, the holder 21 is removed, and the mass of the test piece 20 is measured with an electronic balance. From the change in mass of the test piece 20 before and after immersion in distilled water, the amount of distilled water absorbed per unit area of ​​the test piece 20 (g of water / sheet m 2 , 1m 2 Hit. Abbreviated as g / m 2 ) is calculated. Furthermore, the water absorption per unit area (g of water / sheet m 2 ) by the basis weight of the product ply of the test piece 20 to obtain the water absorption per unit area (water g / sheet m 2 ) / basis weight (sheet g / sheet m 2 ) = Water absorption per unit mass (g of water / g of sheet, per 1g. Abbreviated as g / g). Measurements are carried out five times for each sample, and the average value is used.

[0077] <Kitchen towel roll manufacturing method> The kitchen towel roll 1 can be produced, for example, in the following order: (1) papermaking and creping, (2) embossing and bonding, and (3) roll winding. Note that the TAD papermaking method is preferably used in the production (papermaking) process of the kitchen towel sheet 1x.

[0078] In this case, it is preferable that a concave-convex pattern derived from the papermaking process (fabric), different from the above-mentioned embossed pattern, is applied to the kitchen towel sheet 1x in the papermaking process. By having this concave-convex pattern, the water absorption capacity of the kitchen towel sheet 1x can be further increased.

[0079] Note that "originating from the papermaking process" means that in the papermaking process for the kitchen towel sheet 1x, an uneven pattern is imparted between the head box 41 of the papermaking machine and the outlet of the Yankee dryer 46. Specifically, in a part of the papermaking process shown in Figure 6, a paper web 40a in a pulp slurry state is sprayed (supplied) from the head box 41 to between a first fabric (forming fabric) 42 and a second fabric (uneven fabric) 43, and is pulled onto the second fabric (uneven fabric) 43 by a forming roll 44, forming a paper web 40b in a wet paper state. Next, the wet paper 40b is dried together with the second fabric (concave-convex fabric) 43 in a through-air dryer 45, resulting in the formation of concave-convex patterns on the paper web 40c, which is in a dried sheet state. Although two through-air dryers 45 are shown in FIG. 6, a single unit may be used. Although a Yankee hood is shown on the Yankee dryer 46, the hood may be omitted. Furthermore, creping may be performed in the Yankee dryer 46.

[0080] The uneven pattern can be changed as needed by changing the fabric pattern (fine pattern, coarse pattern). Changing the uneven pattern will change the specific volume (paper thickness), but it is preferable to select a pattern that will keep the specific volume in the rolled state within the above-mentioned numerical range.

[0081] As described above, according to this embodiment, it is possible to provide a kitchen towel roll that has a low drying load in the TAD process and is excellent in water absorbency and feel.

[0082] Although the present invention has been described above using embodiments, it goes without saying that the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various modifications and improvements can be made to the above embodiments. Furthermore, it is clear from the claims that such modifications and improvements can also be included within the technical scope of the present invention. [Example]

[0083] The present invention will be described in detail below with reference to examples, but the present invention is not limited to the examples shown below.

[0084] The kitchen towel rolls of Examples 1 to 11 and Comparative Examples 1 to 4 shown in Table 1 were manufactured through the following processes: (1) papermaking and creping, (2) embossing and laminating, and (3) roll winding. The kitchen towel roll packages of all Examples and Comparative Examples were measured for the above-mentioned parameters and evaluated as follows. Note that parameters other than those evaluated below were measured according to the standards or measurement methods described above.

[0085] 1.Water absorption The amount of water absorbed per unit area of ​​the produced kitchen towel sheets was measured and evaluated on a four-point scale according to the following criteria: ◎: Water absorption per unit area is 380g / m 2 When the above 〇: Water absorption per unit area is 330g / m 2 More than 380g / m 2 When less than △: Water absorption per unit area is 290g / m 2 More than 330g / m 2 When less than ×: Water absorption per unit area is 290g / m 2 When less than

[0086] 2. Drying stress during manufacturing The drying load during the production of kitchen towel sheets was compared with that of conventional kitchen towel sheets produced using TAD, and the energy consumption during the TAD drying process was evaluated on a four-point scale. The evaluation criteria are as follows: ◎: The drying load was significantly reduced, and when the TAD temperature was adjusted so that the moisture content at the TAD outlet was similar, the energy consumption per sheet basis weight was 90% or less compared to conventional kitchen towel sheets manufactured with the TAD. 〇: The drying load was reduced, and when the TAD temperature was adjusted to achieve a similar moisture content at the TAD outlet, the energy consumption per sheet basis weight was 91% to 95% of that of conventional kitchen towel sheets produced with the TAD. △: The drying load was slightly reduced, and when the TAD temperature was adjusted so that the moisture content at the TAD outlet was similar, the energy consumption per sheet basis weight was 96% to 99% compared to conventional kitchen towel sheets produced with the TAD. ×: The drying load was the same as or worse than before, and when the TAD temperature was adjusted so that the moisture content at the TAD outlet was the same, the energy consumption per sheet basis weight was 100% or more compared to conventional kitchen towel sheets produced with the TAD.

[0087] 3. Texture (rough) The feel of the manufactured kitchen towel sheets was evaluated by 30 monitors, who evaluated them on a four-point scale based on the number of people who felt that the sheets were "stiff and had a poor feel." The evaluation criteria were as follows: ◎: 0-1 people felt that the sheet was stiff and had a poor feel 〇: 2-4 people felt that the seat was stiff and had a poor feel △: 5-7 people felt that the seat was stiff and had a poor feel ×: Eight or more people felt that the sheet was stiff and had a poor feel

[0088] [Table 1]

[0089] As is clear from the results shown in Table 1, the kitchen towel rolls of Examples 1 to 11 were good in water absorbency, drying load during production, and feel. In contrast, the sheets of Comparative Examples 1 to 4 were all poor in water absorbency, drying load during production, and feel. Therefore, it was confirmed that the kitchen towel roll of the present invention has a low drying load in the TAD process and can provide a kitchen towel roll that is excellent in water absorbency and feel. [Explanation of symbols]

[0090] 1 kitchen towel roll 1a surface 1b back side 1e The outermost edge of a kitchen towel roll 1x kitchen towel sheet 2 Paper tube 10 Embossing Pattern 11 Radial Embossing 12, 12A, 12B, 12C Closed ring structure embossing 12a Reference point 12b,12c measurement point 12x reference line 12y,12z auxiliary line 20 test specimens 20a Corner 21 Holder 40a, 40b, 40c Paper web 41 Headbox 42,43 Fabric 44 Forming roll 45 Through Air Dryer 46 Yankee Dryer 100 Linear embossed part

Claims

1. A kitchen towel roll is a kitchen towel sheet formed by laminating two plies of sheets having an embossed pattern on at least the front ply, the kitchen towel sheet being wound into a roll, The mass ratio of softwood bleached kraft pulp (NBKP) to hardwood bleached kraft pulp (LBKP) contained in the kitchen towel sheet is 40 to 90 mass%:10 to 60 mass%, The water absorption capacity per unit area of ​​the kitchen towel sheet is 290 g / m ２ 610g / m or more ２ A kitchen towel roll characterized by:

2. 2. The kitchen towel roll according to claim 1, wherein the kitchen towel sheet has a pattern of protrusions and recesses derived from a papermaking process, which is different from the embossed pattern.

3. The basis weight of the kitchen towel sheet per two plies is 30 g / m ２ 54g / m or more ２ 2. The kitchen towel roll of claim 1, wherein:

4. 2. The kitchen towel roll according to claim 1, wherein the ratio (DMDT / DCDT) of the tensile strength in the MD direction in a dry state according to JIS P 8113 of the kitchen towel sheet to the tensile strength in the CD direction in a dry state according to JIS P 8113 (DCDT) is 0.8 or more and 1.4 or less.

5. The specific volume of the kitchen towel sheet is 7 cm ３ / g or more 23cm ３ 2. The kitchen towel roll of claim 1, wherein the kinematic viscosity is 1 / g or less.

6. 2. The kitchen towel roll according to claim 1, wherein the kitchen towel sheet has a tensile strength (GMT) of 480 cN / 25 mm or more and 1450 cN / 25 mm or less, which is the square root of the product of the tensile strength (DMDT) in the machine direction when dry according to JIS P 8113 and the tensile strength (DCDT) in the CD direction when dry according to JIS P 8113.

7. 2. The kitchen towel roll according to claim 1, wherein the embossing pattern includes a radial embossing and a closed-ring structure embossing.

8. the embossing pattern includes a linear embossing portion, 2. The kitchen towel roll according to claim 1, wherein the proportion of the linear embossed portions included in the embossed pattern is 20% or more.

9. 8. The kitchen towel roll according to claim 7, wherein the radial embossments and the closed-ring structure embossments are alternately arranged at equal intervals.

10. 8. The kitchen towel roll according to claim 7, wherein the arrangement angle of adjacent identical patterns of the radial embossings and the closed-ring structure embossings is 20° or more and 80° or less with respect to the CD direction of the kitchen towel sheet.

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