Kitchen Towel Roll

Abstract

To provide a kitchen towel roll whose surface layer is hardly torn when wiping while having adequate water absorbency and bulkiness, and which has easy wiping property.SOLUTION: Provided is a kitchen towel roll in which a kitchen towel sheet, which is obtained by performing adhesion treatment of a sheet to which an embossed pattern is applied with glue and being laminated in two plies, is wound up in a roll shape. The kitchen towel sheet has a pattern of unevenness derived from a paper-making process different from the embossed pattern, wherein a basis weight of two-plies is 30 g / m2 or more and 54 g / m2 or less, a specific volume is 7 cm3 / g or more and 22 cm3 / g or less, a water absorption amount per 1 m2 of the two-plies is 220 g or more and 600 g or less, an embossing depth in the embossed pattern is 0.06 mm or more and 1.1 mm or less, and a root mean square height of a surface roughness in a portion to which no embossed pattern is applied is 35 μm or more and 170 μm or less.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] In recent years, various kitchen towel rolls have been developed, which are made by winding up kitchen towels into a roll. Kitchen towel rolls are often used for cleaning the kitchen and for draining and wiping dishes, and due to their uses, they are required to have sufficient water absorption and strength, so papermaking technologies have been developed to increase water absorption and oil absorption.

[0003] For example, Patent Document 1 discloses a textured belt that can be used in the press process of a tissue papermaking machine to produce high bulk tissue, a press section and papermaking machine for producing a high bulk crepe tissue paper web, and a method for producing the same. Also, U.S. Patent No. 5,399,633 discloses a method for producing soft tissue products, such as facial tissue, bath tissue, and paper towels, using a through-dried fabric having about 5 to about 300 machine direction knuckles per square inch (6.45 square centimeters) that protrude from the plane of the fabric. Furthermore, Patent Document 3 discloses a method for producing a rolled paper product, the method comprising the steps of preparing at least one paper web and embossing the at least one web with an embossed pattern covering at least about 22% of the total surface area of ​​the at least one web, the pattern including at least about 80% linear embossings, and the caliper of the finished product being smaller than the caliper of the embossed base sheet. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5504169 [Patent Document 2] Patent No. 3758702 [Patent Document 3] Special Publication No. 2016-540530 Summary of the Invention [Problem to be solved by the invention]

[0005] The so-called Through Air Drying (TAD) papermaking technology, which uses air drying, produces base paper with high water absorbency and a soft texture, making it excellent for use as base paper for kitchen towel rolls. However, kitchen towel rolls are required to have not only water absorbency and texture, but also to not tear when used to wipe objects. Conventional TAD base paper has problems such as the surface becoming frayed and tearing due to the unevenness of the surface. To address this issue, it is possible to prevent the surface from breaking by making the surface unevenness smaller, but this then reduces the amount of water absorbed.

[0006] Therefore, by adjusting the surface irregularities and then applying embossing, it is possible to obtain a bulky kitchen towel roll with excellent water absorbency while suppressing surface tearing. However, in this case, an embossing pattern that creates fine irregularities on the surface, as is the case with ordinary towel base paper, results in noticeable fuzzing and tearing of the surface. Furthermore, embossing to reduce the paper thickness as in Patent Document 3 reduces the water absorbency of the kitchen towel roll, so it is necessary to apply an embossing pattern suitable for the TAD base paper.

[0007] Therefore, the present invention has been made in consideration of the above problems, and aims to provide a kitchen towel roll that has appropriate water absorbency and bulk, while having a surface that is less likely to tear when wiping, making it easy to wipe. [Means for solving the problem]

[0008] The inventors of the present invention have conducted extensive research to solve the above problems. As a result, they have found that the above problems can be solved by applying a different concavo-convex pattern to the kitchen towel sheet and adjusting the basis weight, specific volume, water absorption, embossing depth, and root mean square height of surface roughness in the area where the embossed pattern is not applied, and have completed the present invention. Specifically, the present invention provides the following.

[0009] (1) A first aspect of the present invention is a kitchen towel roll in which a sheet having an embossed pattern is glued and laminated into two plies, and the resulting kitchen towel sheet is wound into a roll. The kitchen towel sheet has a convexo-concave pattern derived from a 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 has a specific volume of 7cm 3 / g or more 22cm 3 / g or less, 1m of 2 plies 2 The kitchen towel roll is characterized in that the water absorption per unit area is 220 g or more and 600 g or less, the embossing depth in the embossed pattern is 0.06 mm or more and 1.1 mm or less, and the root mean square height of the surface roughness in the portion not provided with the embossed pattern is 35 μm or more and 170 μm or less.

[0010] (2) The second aspect of the present invention is the kitchen towel roll according to (1), wherein the total length of the embossment, which is embossed in the embossing pattern and has a thickness of 0.1 mm to 4 mm and a length of 5 mm or more, is 50 cm / 100 cm. 2 More than 550cm / 100cm 2 It is characterized in that:

[0011] (3) A third aspect of the present invention is a kitchen towel roll according to (1) or (2), characterized in that the ratio of the embossing depth in the embossing pattern to the overall paper thickness of the kitchen towel sheet is 0.02 or more and 0.4 or less.

[0012] (4) A fourth aspect of the present invention is a kitchen towel roll according to any one of (1) to (3), characterized in that the two plies of the kitchen towel sheet have a wet longitudinal tensile strength (WMDT) of 1.5 N / 25 mm or more and 8.0 N / 25 mm or less, and a wet transverse tensile strength (WCDT) of 1.5 N / 25 mm or more and 8.0 N / 25 mm or less, based on the old JIS S 3104.

[0013] (5) A fifth aspect of the present invention is a kitchen towel roll according to any one of (1) to (4), characterized in that the area ratio of the convex portions in the embossing roll for applying the embossing pattern is 4% or more and 40% or less.

[0014] (6) The sixth aspect of the present invention is a kitchen towel roll according to any one of (1) to (5), 2 It is characterized by having a water absorption capacity of 100g or more and 300g or less per unit.

[0015] (7) A seventh aspect of the present invention is a kitchen towel roll according to any one of (1) to (6), characterized in that the water absorption per gram of two plies of the kitchen towel sheet is 6 g or more. Effect of the Invention

[0016] Therefore, according to the present invention, a kitchen towel roll can be provided that has appropriate water absorbency and bulkiness, while the surface layer is less likely to tear when wiping, making it easy to wipe. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a perspective view showing the appearance of a kitchen towel roll of the present invention. [Diagram 2] FIG. 2 is a diagram showing an example of an embossing pattern in the kitchen towel roll of the present invention. [Diagram 3]FIG. 1 is a diagram showing a height profile on an XY plane taken by a microscope using shading. [Figure 4] FIG. 1 is a graph showing a height profile on an XY plane obtained by a microscope. [Diagram 5] FIG. 13 is a diagram showing how to determine the embossing depth for an embossing pattern. [Figure 6] FIG. 13 is a diagram showing, by using shading, the height profile of a non-embossed portion on the XY plane as viewed by a microscope. [Figure 7] FIG. 2 is a diagram showing a method for measuring the water absorption of the kitchen towel roll of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, the embodiments of the present invention will be described in detail. However, the following embodiments are presented for the purpose of illustration, and the present invention is not limited to the embodiments shown below.

[0019] <Kitchen towel roll> Fig. 1 is a perspective view showing the appearance of a kitchen towel roll 1 of the present invention. The kitchen towel roll 1 of the present invention is a kitchen towel sheet 1x formed by gluing sheets with an embossed pattern and laminating them into two plies, which is then wound into a roll. It is preferable that the kitchen towel sheet 1x is perforated in the width direction at equal intervals in the machine direction from the outermost roll edge 1e of the kitchen towel sheet 1x (not shown).

[0020] Also, as shown in FIG. 1, of the surfaces of kitchen towel sheet 1x, the surface facing the outside of the roll is referred to as surface 1a (the surface of kitchen towel sheet 1x), and the surface facing the center of the roll is referred to as back surface 1b (the back surface of kitchen towel sheet 1x).

[0021] (Roll length and diameter) The roll length of the kitchen towel roll 1 is preferably 14 m or more and 44 m or less. The roll diameter DR of the kitchen towel roll 1 is preferably 110 mm or more and 189 mm or less. If the roll length is less than 14 m, the roll needs to be replaced more frequently, and if the roll length exceeds 44 m, the roll is bulky. If the roll diameter DR is less than 110 mm, the water absorption capacity is poor or the roll length is short and the roll needs to be replaced more frequently, and if the roll diameter DR exceeds 189 mm, the roll is bulky or the roll density is low, so that the water absorption capacity is not improved despite the bulk.

[0022] The winding length is more preferably 21 m or more and 37 m or less, and even more preferably 25 m or more and 33 m or less. The winding diameter DR is more preferably 130 mm or more and 176 mm or less, and even more preferably 140 mm or more and 163 mm or less. The roll length is measured by measuring the length of 10 sheets of kitchen towel sheets 1x between the perforations of kitchen towel roll 1. After that, the number of sheets in kitchen towel roll 1 is measured, and the roll length is calculated proportionally from the length of 10 sheets and the number of sheets. For example, if the length of 10 sheets is 1.80 m and the number of sheets is 150, the roll length is 1.80 m x (150 / 10) = 27 m. If kitchen towel roll 1 does not have perforations, the roll length can be measured by actual measurement. The roll diameter DR is measured using a diameter rule manufactured by Muratec KDS Co., Ltd. The measurement is performed by measuring 10 kitchen towel rolls 1, and the measurement results are averaged. Furthermore, the length between the perforations (the length of the sheet in the machine direction) is preferably 100 mm to 270 mm, more preferably 125 mm to 240 mm, and even more preferably 150 mm to 210 mm. By keeping it within this range, when using the kitchen towel roll 1 with good water absorption as in the present application, the area used becomes appropriate, making wiping easier.

[0023] (Roll width and roll weight) The roll width of the kitchen towel roll 1 is preferably 150 mm to 380 mm, more preferably 200 mm to 340 mm, and even more preferably 250 mm to 300 mm. By setting the roll width within this range, when using the kitchen towel roll 1 having suitable water absorbency and bulkiness as in the present application, the area used becomes appropriate, and the amount of water absorption can be improved. The roll mass of the kitchen towel roll 1 is preferably 160 g to 550 g, more preferably 230 g to 450 g, and even more preferably 270 g to 380 g. By setting the roll mass within this range, when using the kitchen towel roll 1 having suitable water absorbency and bulkiness as in the present application, it is possible to reduce bulk and improve the frequency of replacement. The roll mass is the mass per 280 mm of roll width, not including the core (paper tube). If the roll width is not 280 mm, it is converted to the mass per 280 mm by proportional calculation.

[0024] (Roll density and winding density) The roll density of kitchen towel roll 1 is 0.04g / cm 3 More than 0.15g / cm 3 The winding density is preferably 0.22 m / cm or less. 2 More than 0.68m / cm 2 The roll density of the kitchen towel roll 1 is preferably 0.04 g / cm or less. 3 or the winding density is less than 0.22m / cm 2 If the roll density of the kitchen towel roll 1 is less than 0.15 g / cm, the water absorption amount is not improved even though the kitchen towel roll 1 is bulky. 3 or the winding density is 0.68m / cm 2 If it exceeds this value, the paper thickness and specific volume will be low and the water absorption will be poor. The roll density of kitchen towel roll 1 is 0.05 g / cm 3 More than 0.13g / cm 3 More preferably, it is 0.06 g / cm or less. 3 More than 0.09g / cm 3The winding density of the kitchen towel roll 1 is preferably 0.25 m / cm or less. 2 More than 0.54m / cm 2 More preferably, it is 0.28 m / cm or less. 2 More than 0.40m / cm 2 It is even more preferable that:

[0025] 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 outer diameter part of the roll (winding diameter DR) - (cross-sectional area of ​​the outer diameter part of the core (paper tube))}. The core outer diameter DI is the diameter of the center hole of the roll. For example, in the case of a winding length of 27 m, 2 plies, winding diameter DR of 150 mm, and core outer diameter DI of 39 mm, winding density = (27 m × 2) ÷ {3.14 × (150 mm ÷ 2 ÷ 10) 2 -3.14×(39mm÷2÷10) 2}=0.33m / cm 2 If kitchen towel roll 1 does not have a core, the diameter of the center hole is taken as the core outer diameter DI. The roll density is expressed as (roll mass) ÷ (roll volume). The roll mass is the mass of the kitchen towel roll 1 per 280 mm of roll width. 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 part of the core)] × roll width (converted per 280 mm). For example, if the roll mass (excluding the core) per 280 mm of roll width 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×(39mm÷2÷10) 2}×(280mm÷10)]=0.083g / cm 3 If kitchen towel roll 1 does not have a core, the diameter of the center hole is taken as the core outer diameter DI.

[0026] (Basic weight) The basis weight of 2 plies of 1x kitchen towel sheet is 30g / m 2 More than 54g / m 2 The basis weight of the two plies is 30 g / m 2If the weight is less than 54g / m, the water absorption of the kitchen towel sheet 1x is likely to be low. 2 If it exceeds this, it will be difficult to follow the shape of the object and will be difficult to wipe off. The basis weight of the two plies of one kitchen towel sheet is 34 g / m 2 More than 50g / m 2 Preferably, it is 38 g / m or less. 2 More than 46g / m 2 It is more preferable that the basis weight is not more than 1000 g / m2. The basis weight is measured based on JIS P 8124.

[0027] In addition, the basis weight per ply of the kitchen towel sheet 1x is 14 g / m2 for both the front surface 1a and the back surface 1b. 2 More than 28g / m 2 It is preferable that the thickness is less than 16 g / m 2 More than 26g / m 2 More preferably, it is 18 g / m or less. 2 More than 24g / m 2 The basis weight per ply is determined by measuring the basis weights of two plies, peeling the plies, measuring the masses of the front surface 1a and the back surface 1b, and calculating the basis weights of the front surface 1a and the back surface 1b from the mass ratio. Furthermore, in the kitchen towel sheet 1x, the basis weight of the back surface 1b is 0.1 g / m 2 More than 1g / m 2 The surface 1a has an embossed pattern, which will be described later, and therefore tends to have a lower water absorption capacity than the back surface 1b. By increasing the basis weight of the back surface 1b, the water absorption capacity of the back surface 1b can be increased, and thus the overall water absorption capacity can be increased. The basis weight of the back surface 1b is preferably 0.1 g / m2 or more higher than the basis weight of the surface 1a. 2 More than 0.8g / m 2 The higher the better, 0.2 g / m 2 More than 0.5g / m 2 The higher the value, the more preferable it is.

[0028] (paper thickness) In addition, the paper thickness of the kitchen towel sheet 1x is preferably 1.3 mm / 10 sheets or more and 5 mm / 10 sheets or less. If the paper thickness is less than 1.3 mm / 10 sheets, the water absorption of the kitchen towel sheet 1x is inferior, and if the paper thickness exceeds 5 mm / 10 sheets, the water absorption is not improved despite the bulk. The paper thickness of the kitchen towel sheet 1x is more preferably 2.0 mm / 10 sheets or more and 4.4 mm / 10 sheets or less, and even more preferably 2.6 mm / 10 sheets or more and 3.8 mm / 10 sheets or less. The paper thickness is measured using a thickness gauge (dial thickness gauge "PEACOCK" manufactured by Ozaki Seisakusho Co., Ltd.). The measurement conditions are a measurement load of 3.7 kPa, a measuring probe diameter of 30 mm, a sample is placed between the measuring probe and the measuring table, and the gauge is read when the measuring probe is lowered at a speed of 1 mm or less per second. Five sets of kitchen towel sheets 1x laminated in 2 plies are stacked and measured as 10 sheets. The measurement is also repeated 10 times at different locations and the results are averaged.

[0029] (embossed pattern) The kitchen towel roll 1 (kitchen towel sheet 1x) of the present invention is embossed and has an embossed pattern. The kitchen towel sheet 1x of the present invention is laminated into two plies after embossing. When laminating the two plies, a ply bond glue is used and applied to bond them. By bonding them into two plies in this way, the adhesion of the plies becomes strong, and even if the kitchen towel sheet 1x gets wet during wiping, the plies do not peel off and are less likely to tear.

[0030] The ply on the surface 1a of the kitchen towel sheet 1x is provided with an embossed pattern. By providing the embossed pattern on the surface 1a, the embossed portion of the embossed pattern can be applied with glue for adhesion treatment, so that the ply of the kitchen towel sheet 1x is less likely to peel off, and the water absorption can be kept within a certain range. The embossed pattern is not particularly limited as long as it is a pattern that is generally applied to kitchen towels, such as a dot pattern or a line pattern, but is preferably a linear embossed pattern. The linear embossed pattern is not particularly limited as long as one pattern includes two types of figures, namely, a figure having a substantially circular shape and another pattern inside, and a figure that is substantially linearly symmetrical in the vertical and horizontal directions as a whole and includes a combination of multiple curves and figures, as shown in FIG. 2. As for the substantially circular shape, it is preferable that the substantially circular shape is doubled. As for the dimensions of the embossed pattern, the rectangle E (E is not the embossed pattern) surrounding the embossed pattern is preferably a square with sides of 2 cm to 25 cm, more preferably a square with sides of 5 cm to 20 cm, and even more preferably a square with sides of 8 cm to 15 cm. The length direction of this rectangle E is preferably parallel to the flow direction of the kitchen towel roll 1, and the width direction is preferably parallel to the width direction of the kitchen towel roll 1, but may be inclined. By using such a pattern, in the kitchen towel sheet 1x having a high water absorption capacity as in the present application, the water absorption capacity can be improved, and the ply is less likely to peel off, resulting in good wiping properties.

[0031] In this case, for linear embossing patterns with a thickness of 0.1 mm to 4 mm and a length of 5 mm or more, the total length of the embossing plus the length of the embossing is 50 cm / 100 cm. 2 More than 550cm / 100cm 2 Preferably less than 80cm / 100cm 2 More than 410cm / 100cm 2 More preferably, it is 110cm / 100cm or less. 2 More than 300cm / 100cm 2It is more preferable that the total length is 50cm / 100cm or less. 2 If it is less than 550cm / 100cm, the surface layer of the kitchen towel sheet 1x will be easily torn during wiping. 2 If the temperature exceeds this limit, the kitchen towel sheet will become crushed and its absorbency will decrease. The above total length is measured by adding up the lengths of all embossments with a thickness of 0.1 mm to 4 mm and a length of 5 mm or more inside a rectangle E that includes one embossed pattern as shown in Figure 2, and the total length is 100 cm. 2 The total length per square is defined as 10 cm. The size of one side of the rectangle E can be changed as appropriate depending on the size of the embossed pattern. If an embossed pattern adjacent to an embossed pattern included in the rectangle is included in the rectangle that includes all the embossed patterns, the length of the adjacent embossed pattern is also measured and included in the total length. If the size of one side of the rectangle E cannot be clearly determined by the embossed pattern, the size of the rectangle E is set to 10 x 10 cm, and the total length of the embossed length included in the rectangle E is measured. By setting the total length within the above range, the water absorption can be improved in the kitchen towel sheet 1x having high water absorption as in the present application, and the ply is less likely to peel off, resulting in good wiping properties. The total length is measured by the above-mentioned method. It is also possible to measure using a general microscope.

[0032] In the embossing pattern, the embossing depth is 0.06 mm or more and 1.1 mm or less. If the embossing depth is less than 0.06 mm, the surface layer of the kitchen towel sheet 1x is likely to tear during wiping. If the depth exceeds 1.1 mm, the kitchen towel sheet 1x is likely to be crushed and the water absorbency is likely to be reduced. The depth of the embossing in the embossing pattern is preferably 0.10 mm or more and 0.80 mm or less, and more preferably 0.20 mm or more and 0.55 mm or less.

[0033] The depth of the embossing is measured using a microscope. As a microscope, a product name "One Shot 3D Measuring Macroscope VR-3100" manufactured by KEYENCE Corporation can be used. As software for observing, measuring, and analyzing microscope images, a product name "VR-H1A" can be used. The measurement conditions are a magnification of 25 times and a field of view area of ​​12 mm x 9 mm. The measurement magnification and field of view area may be changed as appropriate depending on the desired size of the embossing.

[0034] FIG. 3 shows a height profile on the XY plane taken by a microscope, and the height of the surface of the kitchen towel sheet 1x is represented by shading. The linear areas in FIG. 3 that are shaded differently from the surroundings indicate individual embossments. The depth of the embossment is determined by measuring the height difference of the embossment using the microscope. The measurement is performed on the surface 1a side of the kitchen towel sheet 1x. In addition, when measuring, three turns of the kitchen towel sheet 1x are removed from the kitchen towel roll 1, and the fourth turn of the kitchen towel sheet 1x is used to measure the two-ply sheet. In addition, if there are perforations, all of them are avoided during the measurement. First, a line segment AB is drawn as shown in FIG. 3 to obtain a height profile as shown in FIG. 4. The line segment AB may be drawn so as to cross the embossments. The line segment AB is drawn in the width direction (CD direction) of the kitchen towel sheet 1x, but if the interval between the embosses is narrow, for example, 2 mm or less, and the height of the convex portion described below becomes low, the line segment may be drawn diagonally or in the flow direction. The height profile is a (measured) cross-sectional curve S that represents the unevenness of the actual sample surface of the kitchen towel sheet 1x, but it also includes noise (steep peaks due to fiber clumps on the surface of the kitchen towel sheet 1x, fibers that grow in a whisker-like shape, or areas without fibers), and it is necessary to remove such noise peaks when calculating the height difference of the unevenness.

[0035] Therefore, the (measured) cross-sectional curve S in FIG. 4 is smoothed by setting the filter size of the weighted average radio button to ±12 to obtain the cross-sectional curve W in FIG. 5. The smoothing using the filter of the weighted average radio button can be obtained automatically by using the above-mentioned analysis software. Then, in the graph shown in FIG. 5, the average value of the maximum values ​​on the vertical axis of the graph of the convex part H1 and the convex part H2 adjacent to the convex part H1 is calculated, and the minimum value on the vertical axis of the concave part D1 sandwiched between the convex parts H1 and H2 is obtained. The value obtained by subtracting the minimum value from the average value of the maximum values ​​thus obtained is set as the provisional emboss depth. Then, as shown in FIG. 5, the same measurement is performed on a total of two consecutive locations on the cross-sectional curve W (a total of two consecutive locations of the concave part D1 and the concave part D2 sandwiched between the convex parts H3 and H4) (two measurement results are obtained at this point). After that, kitchen towel roll 1 is rotated 90 degrees three times in the flow direction of kitchen towel sheet 1x, and the same measurement as above is taken at each position (a total of four measurement positions in the flow direction), and the average value of the total eight positions (2 x 4) is ultimately used as the embossing depth. In addition, since the kitchen towel sheet 1x of the present invention has a convex-concave pattern derived from the papermaking process that is different from the embossed pattern, there is variation in the height of the convex parts on the left and right sides that sandwich the concave part. Therefore, when the difference in the vertical axis between the convex parts that sandwich the concave part (for example, the convex parts H3 and H4 that sandwich the concave part D2) is 0.2 mm or more, the measurement is performed at a location that avoids that part.

[0036] Furthermore, the ratio of the embossing depth in the embossing pattern to the overall paper thickness of the kitchen towel sheet 1x, that is, the ratio of the embossing depth in the embossing pattern to the overall paper thickness of the kitchen towel sheet 1x, is preferably 0.02 or more and 0.4 or less. If the ratio is less than 0.02, the surface layer of the kitchen towel sheet 1x is likely to tear during wiping. If the ratio exceeds 0.4, the kitchen towel sheet 1x is likely to be crushed and its water absorption is likely to be reduced. In addition, the ratio of the embossing depth in the embossing pattern to the overall paper thickness of the kitchen towel sheet 1x is more preferably 0.04 or more and 0.35 or less, and even more preferably 0.08 or more and 0.20 or less.

[0037] There is no particular restriction on whether the ply on the back surface 1b of the kitchen towel sheet 1x has an embossed pattern, as long as it has a pattern of protrusions and recesses derived from the papermaking process that is different from the embossed pattern. It may be nested embossed or pin-to-pin embossed, or may not be embossed, but nested embossing or no embossing is preferred, and no embossing is more preferred. Conventional kitchen towels ensure water absorption by using pin-to-pin or nested formats, but when using thick base paper as in the present application, the paper may be crushed by providing embossing, which may reduce the water absorption. For this reason, it is preferred that the front surface 1a is linearly embossed and the back surface 1b is not embossed.

[0038] At this time, the surface roughness root mean square height Sq of the part of the kitchen towel sheet 1x where the embossed pattern is not applied (hereinafter also referred to as the non-embossed part) is 35 μm or more and 170 μm or less, preferably 50 μm or more and 150 μm or less, and more preferably 60 μm or more and 100 μm or less. If the surface roughness root mean square height Sq is less than 35 μm, the specific surface area of ​​the surface layer is small and the water absorption is likely to be low. Also, if the surface roughness root mean square height Sq exceeds 170 μm, the surface layer is likely to break during wiping. The root mean square height Sq of the surface roughness of the non-embossed portion is measured using a microscope. As with the emboss depth described above, a microscope with the product name "One Shot 3D Measuring Macroscope VR-3100" manufactured by KEYENCE Corporation can be used. The product name "VR-H1A" can be used as software for observing, measuring, and analyzing microscope images. The measurement conditions are a magnification of 38 times and a field of view area of ​​8 mm x 6 mm. The measurement magnification and field of view area may be changed as appropriate depending on the desired size of the emboss.

[0039] For the obtained image shown in Figure 6, a filter is set in the same way as for the embossing depth described above. Specifically, an S-filter (low pass filter) is set to remove components with a scale smaller than the cutoff wavelength from the image, and an L-filter (high pass filter) is set to remove components with a scale larger than the cutoff wavelength. Here, the S-filter is set to 500 μm and the L-filter to 8 mm. By selecting the S-filter and L-filter, the root mean square height Sq is automatically calculated. As with the embossing depth, the non-embossed portion is measured by removing three turns of kitchen towel sheet 1x from kitchen towel roll 1, and using the fourth turn of kitchen towel sheet 1x to measure the two-ply sheet. Also, if there are perforations, these are avoided when measuring. Measurements are taken at two locations across the width of kitchen towel roll 1, and then kitchen towel roll 1 is rotated 90 degrees three times in the flow direction of kitchen towel sheet 1x, and the same measurements are taken at each position (a total of four measurement locations in the flow direction), and the average value of the total eight locations (2 x 4) is finally adopted as the root mean square height Sq.

[0040] (Water absorption) In the present invention, 1m of 2 plies of kitchen towel sheet 1x 2 The water absorption capacity per unit is 220g to 600g. 2 If the water absorption per unit area is less than 220g, the water absorption will be low and one kitchen towel sheet will not be able to wipe off enough water. If the water absorption per unit area is more than 600g, the kitchen towel sheet will be easily torn when absorbing water and will be difficult to wipe off. 2 The water absorption per unit is preferably 270 g or more and 550 g or less, and more preferably 370 g or more and 480 g or less. In addition, it is preferable that the water absorption per gram of the two plies of the kitchen towel sheet 1x is 6 g or more. If the water absorption per gram is less than 6 g, the water absorption is low and one kitchen towel sheet 1x cannot wipe off the water sufficiently. In addition, the upper limit of the water absorption per gram is not particularly limited, but if the value is too high, the kitchen towel sheet 1x may break or the plies may peel off when absorbing water, making it difficult to wipe off the water. In addition, the water absorption per gram is more preferably 7.0 g or more and 14.0 g or less, and even more preferably 8.0 g or more and 12.0 g or less.

[0041] Plus 1x kitchen towel sheet, 1m between 2 plies 2 The water absorption per meter between two plies is preferably 100g or more and 300g or less. 2 If the water absorption per unit area is less than 100g, the water absorption will be low and one kitchen towel sheet 1x will not be able to wipe off enough water, and if it exceeds 300g, the kitchen towel sheet 1x will tear or the ply will peel off when it absorbs water, making it difficult to wipe off water. 2 The water absorption per meter is for 2 plies. 2 From the amount of water absorbed per m of one ply (surface 1a) described later, 2 Water absorption per m2 and 1 ply (back side 1b) 2 This is the value obtained by subtracting the amount of water absorbed per unit area. In addition, 1m between two plies 2 The water absorption per unit is more preferably 130 g or more and 280 g or less, and further preferably 160 g or more and 260 g or less. The water absorption per unit is measured as follows.

[0042] First, a two-ply kitchen towel sheet 1x is taken and cut using a square template with each piece measuring 7.6 cm (3 inches) to prepare a rectangular test piece with each side measuring 7.6 cm. The mass of the test piece before water absorption is measured using an electronic balance. The test piece is set in a holder 220 (a jig that fixes three points of the test piece, the jig being made of a metal that does not absorb water). Next, distilled water is poured into a commercially available tub to a depth of 2 cm, and the test piece set in the holder 220 is immersed in the distilled water for 2 minutes. After immersion for 2 minutes, the test piece is taken out of the distilled water together with the holder 220, and the band 210 is attached to one corner 200d of the test piece 200 as shown in FIG. 7. The band 210 is made by cutting the same kitchen towel sheet 1x as the sample to be measured into a size of 2 mm wide x 15 mm long, peeling off the ply, and using one ply on the back side, attaching it to a part of the test piece 200 6 mm from the corner 200d toward the center. Next, the holder 220 and the test piece 200 are hung from a rod installed in an empty water tank so that the corner 200a facing the corner 200d is on top, and the lid of the water tank is closed and left for 10 minutes. Thereafter, the holder 220 and the test piece 200 are taken out of the water tank, the band 210 and the holder 220 are removed, and the mass of the test piece 200 is measured with an electronic balance. From the change in mass of the test piece 200 before and after immersion in distilled water, 2 Absorption of distilled water per sheet (g water / m 2 ) is calculated. 2 Water absorption per sheet (g water / m 2 ) by the basis weight of two plies of the test piece 200, 2 Water absorption per sheet (g water / m 2 ) / grammage(sheet g / sheet m 2 ) = Water absorption per gram (g water / g sheet). Measurements are carried out five times for each sample, and the average value is used. The water absorption of one ply is measured by cutting a kitchen towel sheet 1x overlapped with two plies using a square template with each side being 7.6 cm (3 inches) to obtain a rectangular test piece 200 with each side being 7.6 cm, and then peeling the plies off to obtain the test piece 200 for measuring the water absorption of one ply. The measurement method is the same as for two ply. This measurement is performed according to JIS P 8111 at a temperature of 23±1°C and a humidity of 50±2%. The distilled water is kept at 23±1°C.

[0043] In the present invention, 1 m of 1 ply (surface 1a) of the kitchen towel sheet 1x 2The water absorption per m of one ply (back surface 1b) of the kitchen towel sheet 1x is preferably 50 g or more and 160 g or less, more preferably 60 g or more and 145 g or less, and even more preferably 70 g or more and 130 g or less. 2 The water absorption per unit weight is preferably 50 g or more and 165 g or less, more preferably 60 g or more and 150 g or less, and even more preferably 70 g or more and 135 g or less. The water absorption per gram of one ply (front surface 1a) of the kitchen towel sheet 1x is preferably 3.0 g or more, more preferably 3.5 g to 7.0 g or less, and even more preferably 4.0 g to 6.0 g or less. On the other hand, the water absorption per gram of one ply (back surface 1b) of the kitchen towel sheet 1x is preferably 3.1 g or more, more preferably 3.6 g to 7.1 g or less, and even more preferably 4.1 g to 6.1 g or less.

[0044] (Core outer diameter) Furthermore, the core outer diameter DI, which is the outer diameter of the core of the kitchen towel roll 1 of the present invention, is preferably 25 mm to 55 mm, more preferably 30 mm to 50 mm, and even more preferably 35 mm to 45 mm. By having the core outer diameter DI within the above range, the winding density of the kitchen towel roll 1 can be favorably maintained while the kitchen towel roll 1 is not bulky, making it easier to fit into a kitchen towel holder, and also making the kitchen towel roll 1 easier to handle during production. The core outer diameter DI was measured using a diameter rule manufactured by Muratec KDS Co., Ltd. Ten kitchen towel rolls 1 were measured, and the measurement results were averaged. Furthermore, the mass of the core (paper tube) per 280 mm roll width is preferably 5 g to 22 g, more preferably 7 g to 17 g, and even more preferably 9 g to 13 g.

[0045] (specific volume) The specific volume of one kitchen towel sheet is 7cm 3 / g or more 22cm 3 / g or less. The specific volume of one kitchen towel sheet is 7 cm 3 If it is less than 22 cm / g, it will be difficult to follow the shape of the object and difficult to wipe off. 3 If the specific volume exceeds 9 cm3 / g, the water absorption capacity of the kitchen towel sheet 1x tends to be low. 3 / g or more 20cm 3 / g or less, and 3 / g or more 17cm 3 The specific volume is calculated by dividing the paper thickness per two plies of 1x kitchen towel sheet by the basis weight per two plies, and expressing the volume cm per unit g. 3 It is expressed as:

[0046] (DMDT and DCDT) The tensile strength in the machine direction when dry based on JIS P 8113 of the two plies of the kitchen towel sheet 1x is preferably 4.5 N / 25 mm or more and 21 N / 25 mm or less, and the tensile strength in the cross direction when dry based on JIS P 8113 (DCDT) is preferably 4.5 N / 25 mm or more and 21 N / 25 mm or less. If the DMDT or DCDT is less than 4.5 N / 25 mm, the kitchen towel sheet 1x is likely to fluff and tear when absorbing water, making it difficult to wipe. If the DMDT or DCDT is more than 21 N / 25 mm, the kitchen towel sheet 1x is likely to become hard and difficult to wipe. The DMDT is more preferably 6.0N / 25mm to 17.0N / 25mm, and even more preferably 7.5N / 25mm to 12.0N / 25mm, and the DCDT is more preferably 6.0N / 25mm to 17.0N / 25mm, and even more preferably 7.5N / 25mm to 12.0N / 25mm. Furthermore, the ratio of DMDT to DCDT (DMDT / DCDT) is preferably 0.9 or more and 1.6 or less, more preferably 1.0 or more and 1.4 or less, and even more preferably 1.0 or more and 1.2 or less.

[0047] (WMDT and WCDT) In addition, the wet machine direction tensile strength (WMDT) of the two plies of the kitchen towel sheet 1x based on the old JIS S 3104 is preferably 1.5 N / 25 mm or more and 8.0 N / 25 mm or less, and the wet cross direction tensile strength (WCDT) is preferably 1.5 N / 25 mm or more and 8.0 N / 25 mm or less. If the WMDT or WCDT is less than 1.5 N / 25 mm, the kitchen towel sheet 1x is likely to fluff and tear when absorbing water, making it difficult to wipe. If the WMDT or WCDT is more than 8.0 N / 25 mm, the kitchen towel sheet 1x is likely to become hard and difficult to wipe. The WMDT is more preferably 2.0N / 25mm to 6.0N / 25mm, and even more preferably 2.5N / 25mm to 4.5N / 25mm, and the WCDT is more preferably 2.0N / 25mm to 6.0N / 25mm, and even more preferably 2.5N / 25mm to 4.5N / 25mm. Furthermore, the ratio of WMDT to WCDT (WMDT / WCDT) is preferably 0.9 or more and 1.6 or less, more preferably 1.0 or more and 1.4 or less, and even more preferably 1.0 or more and 1.2 or less.

[0048] (Ply Peel Strength) The ply peel strength of the kitchen towel sheet 1x is preferably 0.04 N / 75 mm or more and 2.1 N / 75 mm or less. If the ply peel strength is less than 0.04 N / 75 mm, the plies will peel off from each other during wiping, making wiping difficult, and if the ply peel strength exceeds 2.1 N / 75 mm, the water absorption of the kitchen towel sheet 1x will tend to be low. The ply peel strength of the kitchen towel sheet 1x is more preferably 0.10 N / 75 mm or more and 1.2 N / 75 mm or less, and further preferably 0.15 N / 75 mm or more and 0.6 N / 75 mm or less. The method for measuring the ply peel strength is based on the tensile test method of JIS P 8113, and can use a tensile tester (STB-1225S, manufactured by A&D Co., Ltd.), and is performed under the standard conditions specified in JIS P 8111. First, a test piece of 75 mm in the width direction and 200 mm in the machine direction is taken from the kitchen towel roll 1 sample. Next, the ply is peeled off 35 mm in the machine direction. One side of the peeled ply is clamped and fixed by an upper grip (width 75 mm) in the machine direction by 15 mm. The other ply is also clamped and fixed by a lower grip (width 75 mm) in the machine direction by 15 mm. The pitch (spacing) of the grippers is 20 mm. Next, the sample is pulled (peeled off) at a pulling speed of 100 mm / min, and strength data is collected. Data is obtained every 20 μm, and the data from 40 mm to 150 mm (measurement length 110 mm) after the start of measurement is averaged to determine the peel strength (N / 75 mm). However, if the perforation is included in the distance from 40 mm to 150 mm after the start of measurement, the distance from the start of measurement can be shortened from 40 mm to, for example, 90 mm (measurement length 50 mm) as long as it does not include the perforation.

[0049] (Method of manufacturing kitchen towel sheets and kitchen towel rolls) The kitchen towel sheet 1x and the kitchen towel roll 1 can be manufactured, for example, in the order of (1) papermaking and creping, (2) embossing, and (3) roll winding. In the manufacturing process, it is preferable to use a through-air dryer technique. In this case, in the papermaking process, a concave-convex pattern derived from the papermaking process (fabric) different from the above-mentioned embossing pattern is applied to the kitchen towel sheet 1x. By having this concave-convex pattern, the water absorption of the kitchen towel sheet 1x is further increased. Note that, "derived from the papermaking process" means that in the papermaking process of the kitchen towel sheet 1x, the concave-convex pattern is applied between the head box of the papermaking machine and the entrance of the Yankee dryer, and the concave-convex pattern is formed by drying the sheet together with the fabric in the through-air dryer section in particular. The uneven pattern can be changed as needed by changing the fabric pattern (fine pattern, coarse pattern). Changing the uneven pattern changes the specific volume (paper thickness), but it is preferable to select a pattern that makes the specific volume (paper thickness) of the base paper fall within the numerical range described below. It is also preferable to select a pattern that makes the root mean square height Sq of the surface roughness of the non-embossed portion of the kitchen towel sheet 1x fall within the numerical range described above.

[0050] When using a base paper made using this through-air dryer, the area ratio of the convex parts on the embossing roll for applying the embossing pattern is preferably 4% or more and 40% or less. If the area ratio is less than 4%, the surface layer of the kitchen towel sheet 1x is easily torn during wiping. If the area ratio is more than 40%, the kitchen towel sheet 1x is easily crushed and the water absorbency is easily reduced. The area ratio of the convex portion is more preferably 6% to 30%, and even more preferably 9% to 18%. The shape of the convex portion and the embossed portion alone can be a circle, an ellipse, a rectangle, a square, a floral pattern, a logo, a letter, etc., without any particular limitation, but as described above, a linear embossment is preferable. As described above, the embossment is preferably provided only on the surface 1a of the kitchen towel sheet 1x.

[0051] In this case, the basis weight of two plies of base paper used to manufacture kitchen towel sheet 1x (twice the basis weight of one ply) is 31 g / m 2 More than 58g / m 2 Preferably, it is 35 g / m or less. 2 More than 54g / m 2 More preferably, it is 39 g / m or less. 2 More than 50g / m 2 The thickness of the paper is preferably 1.4 mm / 10 sheets or more and 5.4 mm / 10 sheets or less, more preferably 2.1 mm / 10 sheets or more and 4.8 mm / 10 sheets or less, and even more preferably 2.7 mm / 10 sheets or more and 4.2 mm / 10 sheets or less. Furthermore, the specific volume is 7 cm 3 / g or more 22cm 3 / g or less, and 3 / g or more 20cm 3 / g or less is more preferable, and 3 / g or more 17cm 3 It is more preferable that the molecular weight is not more than 1 / g.

[0052] The ratio of the embossing depth in the embossing pattern to the thickness of the base paper of the kitchen towel sheet 1x, that is, the ratio of the embossing depth in the embossing pattern to the thickness of the base paper of the kitchen towel sheet 1x, is preferably 0.01 to 0.38, more preferably 0.03 to 0.33, and even more preferably 0.07 to 0.18. By setting it within this range, in the case of the kitchen towel sheet 1x having good water absorption as in the present application, it is possible to improve water absorption by preventing ply peeling without bulkiness. In addition, the difference between the specific volume of the kitchen towel sheet 1x and the specific volume of the base paper (the difference between the specific volume of the kitchen towel sheet 1x and the specific volume of the base paper) is -3 cm to prevent ply peeling without being bulky and to improve water absorption. 3 / g or more 2cm 3 / g or less is preferable, and -2cm 3 / g or more 1cm 3 / g or less is more preferable, and -1cm 3 / g or more 0.5cm 3 / g or less is more preferable, and -0.5 cm 3 / g or more 0cm 3 / g or less is particularly preferred.

[0053] It goes without saying that the present invention is not limited to the above-described embodiments, but covers various modifications and equivalents within the spirit and scope of the present invention. EXAMPLES

[0054] Through the steps of (1) papermaking and creping, (2) embossing, and (3) rolling, the kitchen towel sheets and kitchen towel rolls of Examples 1 to 21 and Comparative Examples 1 to 10 were manufactured. The above-mentioned parameters were measured and evaluated for all the kitchen towel rolls of the above Examples and Comparative Examples. With regard to the embossing pattern, the number and thickness of lines were appropriately changed in each Example and Comparative Example, and the embossing was only provided on the front side of the kitchen towel sheet.

[0055] The produced kitchen towel sheets and kitchen towel rolls were evaluated for the following items. Surface tearing and fuzzing: The monitors used one kitchen towel sheet and evaluated the resistance of the surface to tearing and fuzzing. Water absorbency: Monitors evaluated how much water remained on the sheet when using one kitchen towel. Wipeability: The monitor evaluated the ease of wiping using one kitchen towel sheet.

[0056] For the above three items, 20 monitors selected "good" or "bad" for each evaluation item. The evaluation criteria are as follows, with ◎, ○, and △ being considered as pass. ◎: When 18 to 20 people answered "Good" ○: When 14 to 17 people answered "Good" △: When 10 to 13 people answered "Good" ×: When 6 to 9 people answered "Good" ××: When there are no "good" people or when there are 1 to 5 people

[0057] The results obtained are shown in Tables 1 and 2. [Table 1]

[0058] [Table 2]

[0059] From the above, it can be seen that the kitchen towel roll of the present invention has appropriate water absorbency and bulkiness, while the surface layer is less likely to tear when wiping, making it easy to wipe. [Explanation of symbols]

[0060] 1 kitchen towel roll 1a surface 1b back side 1e The outermost edge of the kitchen towel sheet 1x kitchen towel sheet 200 specimens 200a, 200d corner 210 Obi 220 Holder

Claims

1. A kitchen towel roll is a kitchen towel sheet formed by gluing a sheet having an embossed pattern thereon and laminating the sheet in two plies, the kitchen towel sheet being wound into a roll. The kitchen towel sheet has a pattern of protrusions and recesses derived from a papermaking process that is different from the embossed pattern, The basis weight of the two plies is 30 g / m ２ 54g / m or more ２ The specific volume is 7 cm ３ / g or more 22cm ３ / g or less, 2 ply 1m ２ The water absorption per unit is 220g or more and 600g or less, The embossing depth in the embossing pattern is 0.06 mm or more and 1.1 mm or less, the root mean square height of surface roughness in a portion where the embossed pattern is not applied is 35 μm or more and 170 μm or less; The kitchen towel roll is characterized in that, in the embossing pattern, for embossments each having a thickness of 0.1 mm or more and 4 mm or less and a length of 5 mm or more, the total length when the lengths of the embossments are added is 50 cm / 100 cm 2 or more and 550 cm / 100 cm 2 or less.

2. 2. The kitchen towel roll according to claim 1, wherein a ratio of an embossing depth in the embossing pattern to a paper thickness of the entire kitchen towel sheet is 0.02 or more and 0.4 or less.

3. 3. The kitchen towel roll according to claim 1 or 2, characterized in that the two plies of the kitchen towel sheet have a wet longitudinal tensile strength WMDT of 1.5 N / 25 mm or more and 8.0 N / 25 mm or less, and a wet transverse tensile strength WCDT of 1.5 N / 25 mm or more and 8.0 N / 25 mm or less, based on the old JIS S 3104.

4. 4. The kitchen towel roll according to claim 1, wherein an area ratio of the convex portions in an embossing roll for applying the embossing pattern is 4% or more and 40% or less.

5. 1m between the two plies of the kitchen towel sheet ２ 5. The kitchen towel roll according to claim 1, wherein the water absorption amount per unit area is 100 g or more and 300 g or less.

6. 6. The kitchen towel roll according to claim 1, wherein the water absorption per gram of the two plies of the kitchen towel sheet is 6 g or more.

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