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 a kitchen towel roll.

Background Art

[0002] In recent years, various kitchen towel rolls in which kitchen towels are wound in a roll shape have been developed. Kitchen towel rolls are often used for cleaning in the kitchen, draining and wiping dishes, and sufficient water absorption and strength are required for their uses, and papermaking techniques for increasing water absorption and oil absorption have been developed.

[0003] For example, Patent Document 1 discloses a concavo-convex belt, a press part for manufacturing a high-bulk crepe tissue paper web, and a papermaking machine, and a manufacturing method thereof, in which a high-bulk tissue can be obtained by using a concavo-convex belt in the press process of a tissue papermaking machine. Further, Patent Document 2 discloses a method for manufacturing a flexible tissue product, in which a ventilated and dried tissue product such as a facial tissue, a bath tissue, or a paper towel is manufactured using a ventilated and dried fabric having about 5 to about 300 mechanical-direction concavo-convex knuckles per 6.45 square centimeters (1 square inch) protruding from the plane of the fabric. Furthermore, Patent Document 3 discloses a method for manufacturing a roll-shaped paper product, including a step of preparing at least one paper web and a step of embossing at least one web using an embossing pattern covering at least about 22% of the total surface area of at least one web, the pattern including at least about 80% of linear embossing, and the caliper of the finished product being smaller than the caliper of the embossed base sheet. A roll-shaped paper product and its manufacturing method are disclosed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0005] The so-called TAD (Through Air Drying) papermaking technology using through-air drying is excellent as the base paper for kitchen towel rolls because it can obtain a base paper with high water absorbency and a soft texture. However, for kitchen towel rolls, not only water absorbency and texture are required, but also they should not tear when wiping an object. Conventional TAD base papers have problems such as the surface layer fluffing or tearing due to the unevenness on the surface. To address this problem, by reducing the surface unevenness, tearing of the surface layer can be suppressed, but then the water absorption amount decreases.

[0006] Therefore, by adjusting the surface unevenness and further performing embossing, it is possible to obtain a bulky and highly water-absorbent kitchen towel roll while suppressing tearing of the surface layer. However, at this time, with an embossing pattern that provides fine unevenness on the surface like a normal towel base paper, fluffing and tearing of the surface layer become prominent. Also, if an embossing that reduces the paper thickness as in Patent Document 3 is applied, the water absorbency of the kitchen towel roll decreases, so it is necessary to apply an embossing pattern suitable for the TAD base paper.

[0007] Therefore, the present invention has been made in view of the above problems, and an object thereof is to provide a kitchen towel roll that has appropriate water absorbency and bulkiness, and whose surface layer is difficult to tear and easy to wipe during wiping.

Means for Solving the Problems

[0008] In order to solve the above problems, the inventors of the present invention conducted intensive research. As a result, by applying an uneven pattern different from the embossed pattern and adjusting the basis weight, specific volume, water absorption, depth of the emboss, and root mean square height of the surface roughness in the portion where the embossed pattern is not applied of the kitchen towel sheet, it was found that the above problems can be solved, and the present invention has been completed. Specifically, the present invention provides the following.

[0009] (1) The first aspect of the present invention is a kitchen towel roll in which a sheet with an embossed pattern is adhesively treated with glue and laminated in two plies and wound into a roll, wherein the kitchen towel sheet has an uneven pattern derived from a papermaking process different from the embossed pattern, the basis weight of the two plies is 30 g / m 2 or more and 54 g / m 2 or less, the specific volume is 7 cm 3 / g or more and 22 cm 3 / g or less, the water absorption per 1 m 2 of the two plies is 220 g or more and 600 g or less, the depth of the emboss 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 where the embossed pattern is not applied 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, for the emboss in the embossed pattern 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 embosses are added together is 50 cm / 100 cm 2 or more and 550 cm / 100 cm 2 or less.

[0011] (3) The third aspect of the present invention is the kitchen towel roll according to (1) or (2), wherein the ratio of the depth of the emboss in the embossed pattern to the paper thickness of the entire kitchen towel sheet is 0.02 or more and 0.4 or less.

[0012] (4) The fourth aspect of the present invention is the kitchen towel roll according to any one of (1) to (3), wherein the longitudinal tensile strength WMDT when wet is 1.5 N / 25 mm or more and 8.0 N / 25 mm or less, and the transverse tensile strength WCDT when wet is 1.5 N / 25 mm or more and 8.0 N / 25 mm or less, based on the two-ply old JIS S 3104 of the above kitchen towel sheet.

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

[0014] (6) The sixth aspect of the present invention is the kitchen towel roll according to any one of (1) to (5), wherein the water absorption per 1 m 2 between the two plies of the above kitchen towel sheet is 100 g or more and 300 g or less.

[0015] (7) The seventh aspect of the present invention is the kitchen towel roll according to any one of (1) to (6), wherein the water absorption per 1 g of the two plies of the above kitchen towel sheet is 6 g or more.

Advantages of the Invention

[0016] Therefore, according to the present invention, it is possible to provide a kitchen towel roll that has appropriate water absorption and bulkiness, and is difficult for the surface layer to break during wiping and is easy to wipe.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0018] Hereinafter, embodiments of the present invention will be described in detail. However, the following embodiments are presented for illustrative purposes, 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 the kitchen towel roll 1 of the present invention. The kitchen towel roll 1 of the present invention is a kitchen towel roll 1 obtained by adhesively bonding a sheet with an emboss pattern in a glue and winding a laminated kitchen towel sheet 1x in a roll shape with 2 plies. Note that it is preferable that the kitchen towel sheet 1x is perforated in the width direction at equal intervals in the flow direction from the outermost edge 1e of the outermost winding of the kitchen towel sheet 1x (not shown).

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

[0021] (Roll length and roll diameter) The winding length of the kitchen towel roll 1 is preferably 14 m or more and 44 m or less. Further, the winding diameter DR of the kitchen towel roll 1 is preferably 110 mm or more and 189 mm or less. If the winding length is less than 14 m, the replacement frequency increases, and if it exceeds 44 m, it becomes bulky. If the winding diameter DR is less than 110 mm, the water absorption is poor, the winding length becomes short, and the replacement frequency increases. If the winding diameter DR exceeds 189 mm, it becomes bulky and the roll density becomes low, and it is difficult to improve the water absorption despite being bulky.

[0022] In addition, 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. For the winding length, for the kitchen towel sheet 1x between the stitches of the kitchen towel roll 1, the length of 10 sheets is actually measured. Then, the number of sheets of the kitchen towel roll 1 is actually measured, and the winding length is obtained by proportional calculation from the length of 10 sheets and the number of sheets. For example, when the length of 10 sheets is 1.80 m and the number of sheets is 150 sheets, it becomes 1.80 m × (150 / 10) = 27 m. When there are no stitches on the kitchen towel roll 1, the winding length can be measured by actual measurement. Also, the winding diameter DR of the roll is measured using a diameter rule manufactured by Muratec KDS Co., Ltd. The measurement is performed on 10 kitchen towel rolls 1, and the measurement results are averaged. In addition, the length between the stitches (the length of the sheet in the flow direction) is preferably 100 mm or more and 270 mm or less, more preferably 125 mm or more and 240 mm or less, and even more preferably 150 mm or more and 210 mm or less. By setting it within this range, when using the kitchen towel roll 1 with good water absorption as in the present application, the area to be used becomes appropriate and it becomes easier to wipe.

[0023] (Roll width and roll mass) The roll width of the kitchen towel roll 1 is preferably 150 mm or more and 380 mm or less, more preferably 200 mm or more and 340 mm or less, and still more preferably 250 mm or more and 300 mm or less. By setting it within this range, when using the kitchen towel roll 1 having appropriate water absorption and bulkiness as in the present application, the area to be used becomes appropriate and the water absorption amount can be improved. Also, the roll mass of the kitchen towel roll 1 is preferably 160 g or more and 550 g or less, more preferably 230 g or more and 450 g or less, and still more preferably 270 g or more and 380 g or less. By setting it within this range, when using the kitchen towel roll 1 having appropriate water absorption and bulkiness as in the present application, the replacement frequency can be improved without being bulky. Note that the roll mass is the mass per 280 mm of roll width excluding the core (paper tube). When the roll width is not 280 mm, it is converted to the mass per 280 mm by proportional calculation.

[0024] (Roll density and winding density) The roll density of the kitchen towel roll 1 is preferably 0.04 g / cm 3 or more and 0.15 g / cm 3 or less, and the winding density is preferably 0.22 m / cm 2 or more and 0.68 m / cm 2 or less. If the roll density of the kitchen towel roll 1 is less than 0.04 g / cm 3 or the winding density is less than 0.22 m / cm 2 , it becomes difficult to improve the water absorption amount despite the kitchen towel roll 1 being bulky. Also, if the roll density of the kitchen towel roll 1 exceeds 0.15 g / cm 3 or the winding density exceeds 0.68 m / cm 2 , the paper thickness and specific volume become low and the water absorption amount is inferior. Note that the roll density of the kitchen towel roll 1 is more preferably 0.05 g / cm 3 or more and 0.13 g / cm 3 or less, and more preferably 0.06 g / cm 3 or more and 0.09 g / cm 3It is more preferable that the following holds. The winding density of the kitchen towel roll 1 is 0.25 m / cm 2 or more and 0.54 m / cm 2 or less, more preferably 0.28 m / cm 2 or more and 0.40 m / cm 2 or less.

[0025] The winding density is expressed as (winding length × ply number) ÷ (cross-sectional area of the roll). The cross-sectional area of the roll is expressed as {cross-sectional area of the outer diameter (winding diameter DR) part of the roll - cross-sectional area of the outer diameter part of the core (paper tube)}. The core outer diameter DI is the diameter of the central hole of the roll. For example, when the winding length is 27 m, 2 plies, the winding diameter DR is 150 mm, and the core outer diameter DI is 39 mm, the winding density = (27 m × 2) ÷ {3.14 × (150 mm ÷ 2 ÷ 10) 2 - 3.14 × (39 mm ÷ 2 ÷ 10) 2}= 0.33 m / cm 2 It becomes like this. When there is no core in the kitchen towel roll 1, the diameter of the central hole is taken as the core outer diameter DI. Also, the roll density is expressed as (roll mass) ÷ (volume of the roll). The roll mass is the mass of the kitchen towel roll 1 per 280 mm of the 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 core outer diameter part)] × roll width (converted to per 280 mm). For example, when the roll mass (excluding the core) per 280 mm of the 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 × (39 mm ÷ 2 ÷ 10) 2} × (280 mm ÷ 10)] = 0.083 g / cm 3 It becomes like this. When there is no core in the kitchen towel roll 1, the diameter of the central hole is taken as the core outer diameter DI.

[0026] (Grammage) The grammage of 2 plies of the kitchen towel sheet 1x is 30 g / m 2 or more and 54 g / m 2 or less. When the grammage of 2 plies is 30 g / m 2If it is less than this value, the water absorption of the kitchen towel sheet 1x tends to be low. When the basis weight exceeds 54 g / m 2 it becomes difficult to follow the shape of the object to be wiped and difficult to wipe. The basis weight of 2-ply of the kitchen towel sheet 1x is preferably 34 g / m 2 or more and 50 g / m 2 or less, more preferably 38 g / m 2 or more and 46 g / m 2 or less. The basis weight is measured based on JIS P 8124.

[0027] Also, the basis weight per ply of the kitchen towel sheet 1x is preferably 14 g / m 2 or more and 28 g / m 2 or less, more preferably 16 g / m 2 or more and 26 g / m 2 or less, even more preferably 18 g / m 2 or more and 24 g / m 2 or less. The basis weight per ply is calculated by measuring the basis weight of 2-ply, then peeling the ply, measuring the mass of the front surface 1a and the back surface 1b, and calculating the basis weight 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 preferably 0.1 g / m 2 or more and 1 g / m 2 or less higher than that of the front surface 1a. Since the front surface 1a has an embossed pattern described later, its water absorption is likely to be inferior to that of the back surface 1b. By increasing the basis weight of the back surface 1b, the water absorption of the back surface 1b can be increased, thereby increasing the overall water absorption. The basis weight of the back surface 1b is preferably 0.1 g / m 2 or more and 0.8 g / m 2 or less higher than that of the front surface 1a, more preferably 0.2 g / m 2 or more and 0.5 g / m 2 or less higher than that of the front surface 1a.

[0028] (Paper thickness) Also, 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. If it exceeds 5 mm / 10 sheets, the water absorption is difficult to improve despite being bulky. 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 and a measuring head diameter of 30 mm. A sample is placed between the measuring head and the measuring table, and the gauge is read when the measuring head is lowered at a speed of 1 mm or less per second. Five sets of the kitchen towel sheet 1x laminated in two-ply are stacked and measured as 10 sheets. Also, the measurement is repeated 10 times at different locations and the measurement 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. Also, the kitchen towel sheet 1x in the present invention is embossed on the sheet and then laminated into two-ply. When laminating into two-ply, a ply bond glue (adhesive) is used, and the glue is applied for adhesion treatment. By adhering in this way to make it two-ply, the adhesion of the ply becomes stronger, and even if the kitchen towel sheet 1x gets wet with water during cleaning, it is less likely to tear without ply peeling.

[0030] The ply of the surface 1a of the kitchen towel sheet 1x is provided with an embossed pattern. By applying the embossed pattern to the surface 1a, glue can be applied to the embossed portions of the embossed pattern for adhesion treatment, making it less likely for the ply of the kitchen towel sheet 1x to peel off and enabling the water absorption to be within a certain range. The embossed pattern is not particularly limited as long as it is a pattern commonly applied to kitchen towels, such as dot-shaped or linear patterns, etc., but among them, a linear embossed pattern is preferably used. Specifically, as the linear embossed pattern, as shown in FIG. 2, one pattern includes two figures of two types of figures, one figure having a substantially round-shaped substantially circular shape and another figure having another pattern inside, and the whole is substantially line-symmetric vertically and horizontally, including a combination of a plurality of curves and figures. As long as it is a pattern including two of each of these two types of figures, it is not particularly limited. Regarding the substantially round-shaped substantially circular shape, it is preferably double-layered. Also, as the dimensions of the embossed pattern, the quadrilateral E (E is not the embossed pattern) surrounding the embossed pattern is preferably a square with a side length of 2 cm or more and 25 cm or less, more preferably a square with a side length of 5 cm or more and 20 cm or less, and even more preferably a square with a side length of 8 cm or more and 15 cm or less. Regarding this quadrilateral E, the longitudinal direction is preferably parallel to the flow direction of the kitchen towel roll 1, and the transverse direction is preferably parallel to the width direction of the kitchen towel roll 1, but it may be inclined. By using such a pattern, in the kitchen towel sheet 1x with a high water absorption like the present application, the water absorption can be improved, the ply is also less likely to peel off, and the wiping property is improved.

[0031] At this time, regarding the embosses in the linear embossed pattern with 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 embosses are added is 50 cm / 100 cm 2 or more and 550 cm / 100 cm 2 or less, preferably 80 cm / 100 cm 2 or more and 410 cm / 100 cm 2 or less, more preferably 110 cm / 100 cm 2 or more and 300 cm / 100 cm 2More preferably, the following conditions are met. The total length is 50 cm / 100 cm 2 If it is less than this, the surface layer of the kitchen towel sheet 1x is likely to tear during wiping. If the total length is 550 cm / 100 cm 2 exceeds this, the kitchen towel sheet 1x is likely to be crushed and its water absorption capacity is likely to decrease. The above total length is measured as the total length obtained by adding the emboss lengths for embosses with a thickness of 0.1 mm or more and 4 mm or less and a length of 5 mm or more inside the quadrilateral E that includes all of one emboss pattern as shown in Figure 2, and is the total length per 100 cm 2 The size of one side of this quadrilateral E can be appropriately changed according to the size of the emboss pattern. In the case where an emboss pattern adjacent to the emboss pattern included in the quadrilateral is included within the quadrilateral that includes all the emboss patterns, the length of the adjacent emboss pattern is also measured and included in the total length. Also, when the size of one side of the quadrilateral E cannot be clearly determined by the emboss pattern, the size of the quadrilateral E is set to 10×10 cm, and the total length of the emboss lengths included in this quadrilateral E is measured. By setting the total length within the above range, in the kitchen towel sheet 1x with a high water absorption capacity as in the present application, the water absorption capacity can be improved, the ply is less likely to peel off, and the wiping property is improved. The total length is obtained by actual measurement using the method described above. It may also be measured using a general microscope.

[0032] In the emboss pattern, the depth of the emboss is 0.06 mm or more and 1.1 mm or less. If the depth of the emboss 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 its water absorption capacity is likely to decrease. Note that the depth of the emboss in the emboss 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 emboss is measured using a microscope. As the microscope, the product name "One-shot 3D Measurement Macroscope VR-3100" manufactured by KEYENCE can be used. As the image observation, measurement, and image analysis software for the microscope, the product name "VR-H1A" can be used. Also, the measurement conditions are to measure under the conditions of a magnification of 25 times and a field area of 12 mm × 9 mm. The measurement magnification and field area may be appropriately changed depending on the size of the emboss to be obtained.

[0034] Figure 3 shows the height profile on the X-Y plane by the microscope, and the height of the surface of the kitchen towel sheet 1x is represented by shading. The linear part where the shading in Figure 3 is different from the periphery indicates each emboss. The depth of the emboss is obtained by measuring the height difference of the above-mentioned emboss using the above microscope. The measurement is performed on the surface 1a side of the kitchen towel sheet 1x. Also, at the time of measurement, 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 for measurement in the state of a two-ply sheet. Also, when there are perforations, avoid them all for measurement. First, draw a line segment AB as shown in Figure 3 to obtain the height profile of Figure 4. The line segment AB may be drawn so as to cross the emboss. Also, the line segment AB is drawn in the width direction (CD direction) of the kitchen towel sheet 1x. However, when the interval between the embosses is narrow, for example, 2 mm or less, and the height of the following convex part becomes low, the line segment may be drawn in an oblique direction or in the flow direction. The height profile is the (measured) cross-sectional curve S representing the unevenness of the actual sample surface of the kitchen towel sheet 1x, but it also includes noise (fiber lumps on the surface of the kitchen towel sheet 1x, fibers extending in a whisker shape, or steep peaks caused by parts without fibers). When calculating the height difference of the unevenness, it is necessary to remove such noise peaks.

[0035] Therefore, the cross-sectional curve S in FIG. 4 (measurement) is used with the filter size of the weighted average radio button set to ±12, and the smoothed cross-sectional curve W in FIG. 5 is obtained. Note that the smoothing using the filter of the weighted average radio button can be automatically obtained by using the above analysis software. Then, in the graph shown in FIG. 5, the average value of the maximum values of the vertical axes of the convex portion H1 of the graph and the convex portion H2 adjacent to the convex portion H1 is calculated, and the minimum value of the vertical axis in the concave portion D1 sandwiched between the convex portion H1 and the convex portion H2 is obtained. The numerical value obtained by subtracting the minimum value from the average value of the maximum values thus obtained is set as the provisional embossing depth. Then, as shown in FIG. 5, the same measurement is performed for a total of two consecutive locations (a total of two consecutive locations, the concave portion D1 and the concave portion D2 sandwiched between the convex portion H3 and the convex portion H4) on the cross-sectional curve W (two measurement results are obtained at this time). Thereafter, the same measurement as described above is performed at each position where the kitchen towel roll 1 is rotated three times by 90 degrees each in the flow direction of the kitchen towel sheet 1x (the measurement positions in the flow direction are a total of four locations), and the average value of a total of eight locations (2×4) is finally adopted as the embossing depth. Note that since the kitchen towel sheet 1x of the present invention has an uneven pattern derived from a papermaking process different from the embossing pattern, there is variation in the height of the left and right convex portions sandwiching the concave portion. Therefore, when the difference in the values of the vertical axes of the convex portions sandwiching the concave portion (for example, the convex portion H3 and the convex portion H4 sandwiching the concave portion D2) is 0.2 mm or more, the measurement is performed at a location where that portion is avoided.

[0036] Furthermore, it is preferable that the ratio of the embossing depth in the embossing pattern to the paper thickness of the entire kitchen towel sheet 1x, that is, the ratio of the embossing depth in the embossing pattern / the paper thickness of the entire kitchen towel sheet 1x, is 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 break during wiping. If the ratio exceeds 0.4, the kitchen towel sheet 1x is likely to be crushed and the water absorption is likely to decrease. Note that the ratio of the embossing depth in the embossing pattern / the paper thickness of the entire 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] The back surface 1b of the kitchen towel sheet 1x has no particular limitation on whether or not an embossing pattern is applied, as long as it has an uneven pattern derived from a papermaking process different from the embossing pattern. Whether nested embossing or pin-to-pin embossing is applied, or no embossing is applied, is acceptable, but nested embossing or no embossing is preferred, and no embossing is more preferred. Conventional kitchen towels ensure water absorption in a pin-to-pin or nested form. However, when using a base paper with a high paper thickness as in the present application, if an embossing is provided, the paper may be crushed and the water absorption may decrease. For this reason, it is preferable that the front surface 1a has a linear embossing and the back surface 1b has no embossing.

[0038] At this time, the root mean square height Sq of the surface roughness in the portion of the kitchen towel sheet 1x where no embossing pattern is applied (hereinafter also referred to as the non-embossed portion) 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. When the root mean square height Sq of the surface roughness is less than 35 μm, the specific surface area of the surface layer becomes small and the water absorption tends to be low. Also, when the root mean square height Sq of the surface roughness exceeds 170 μm, the surface layer is likely to be torn during wiping. The root mean square height Sq of the surface roughness of the non-embossed portion is measured using a microscope. As the microscope, the product name "One Shot 3D Measurement Macroscope VR-3100" manufactured by KEYENCE Corporation can be used, similar to the depth of the embossing described above. As the software for observing, measuring, and analyzing the images of the microscope, the product name "VR-H1A" can be used. Also, the measurement conditions are measurement under the conditions of a magnification of 38 times and a field area of 8 mm × 6 mm. The measurement magnification and the field area may be appropriately changed depending on the size of the embossing to be obtained.

[0039] For the obtained image shown in Fig. 6, set the filter in the same way as the emboss depth described above. Specifically, by setting the S-filter (low-pass filter), components with scales smaller than the cut-off wavelength are removed from the image, and by setting the L-filter (high-pass filter), components with scales larger than the cut-off wavelength are removed from the image. Here, the S-filter is 500 μm and the L-filter is 8 mm. If the S-filter and L-filter are selected, the root mean square height Sq is automatically calculated. For the non-embossed part, in the same way as the emboss depth, remove three turns of the kitchen towel sheet 1x from the kitchen towel roll 1, and measure in the state of a two-ply sheet using the fourth turn of the kitchen towel sheet 1x. Also, if there are perforations, avoid them all for measurement. Measure at two locations in the width direction of the kitchen towel roll 1, and then perform the same measurement as above at each position where the kitchen towel roll 1 is rotated three times by 90 degrees each in the flow direction of the kitchen towel sheet 1x (the measurement positions in the flow direction total four locations), and finally adopt the average value of a total of eight locations (2×4) as the root mean square height Sq.

[0040] (Water absorption capacity) In the present invention, the water absorption capacity per 1 m of the two-ply kitchen towel sheet 1x 2 is 220 g or more and 600 g or less. If the water absorption capacity per 1 m 2 is less than 220 g, the water absorbency becomes low and it cannot be wiped sufficiently with a single kitchen towel sheet 1x. If it exceeds 600 g, the kitchen towel sheet 1x is likely to tear during water absorption and it becomes difficult to wipe. Note that the water absorption capacity per 1 m 2 is preferably 270 g or more and 550 g or less, and more preferably 370 g or more and 480 g or less. Also, it is preferable that the water absorption per gram of the two-ply kitchen towel sheet 1x is 6 g or more. If the water absorption per gram is less than 6 g, the water absorbency becomes low and it cannot be wiped sufficiently with a single kitchen towel sheet 1x. Also, although the upper limit of the water absorption per gram is not particularly limited, if the value becomes too high, the kitchen towel sheet 1x may tear or the ply may peel off during water absorption, making it difficult to wipe. Note that 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] Furthermore, the water absorption per meter between the two plies of the kitchen towel sheet 1x 2 is preferably 100 g or more and 300 g or less. If the water absorption per meter between the two plies is less than 100 g, the water absorbency becomes low and it cannot be wiped sufficiently with a single kitchen towel sheet 1x. If it exceeds 300 g, the kitchen towel sheet 1x may tear or the ply may peel off during water absorption, making it difficult to wipe. At this time, the water absorption per meter between the two plies 2 refers to the value obtained by subtracting the water absorption per meter of one ply (front surface 1a) and the water absorption per meter of one ply (back surface 1b), which will be described later, from the water absorption per meter of the two plies. 2 Here, the water absorption per meter between the two plies 2 is the water absorption per meter of the two plies 2 minus the water absorption per meter of one ply (front surface 1a) and the water absorption per meter of one ply (back surface 1b). 2 Note that the water absorption per meter between the two plies 2 is more preferably 130 g or more and 280 g or less, and even more preferably 160 g or more and 260 g or less. The water absorption of each kitchen towel sheet 1x is measured as follows.

[0042] First, a kitchen towel sheet 1x stacked in two plies is sampled, cut using a template with a square of 7.6 cm (3 inches) on one side to produce a test piece in the shape of a rectangle with a side of 7.6 cm. Measure the mass of the test piece before water absorption with an electronic balance. Set the test piece in a holder 220 (a jig for fixing three points of the test piece, and the jig is made of a metal that does not absorb moisture). ​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 unit area 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. On the other hand, for 1 ply (back surface 1b) of the kitchen towel sheet 1x, 1 m 2 The water absorption per unit area 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. In addition, the water absorption per gram of 1 ply (front surface 1a) of the kitchen towel sheet 1x is preferably 3.0 g or more, more preferably 3.5 g or more and 7.0 g or less, and even more preferably 4.0 g or more and 6.0 g or less. On the other hand, the water absorption per gram of 1 ply (back surface 1b) of the kitchen towel sheet 1x is preferably 3.1 g or more, more preferably 3.6 g or more and 7.1 g or less, and even more preferably 4.1 g or more and 6.1 g or less.

[0044] (Core outer diameter) In addition, 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 or more and 55 mm or less, more preferably 30 mm or more and 50 mm or less, and even more preferably 35 mm or more and 45 mm or less. When the core outer diameter DI is within the above range, while suitably maintaining the winding density of the kitchen towel roll 1, the kitchen towel roll 1 does not take up much space, so that it can be easily accommodated in a kitchen towel holder. In addition, the handleability of the kitchen towel roll 1 during manufacturing also becomes good. The core outer diameter DI was measured using a diameter rule manufactured by Muratec KDS Co., Ltd. The measurement was performed on 10 kitchen towel rolls 1, and the measurement results were averaged. Furthermore, the mass of the core (paper tube) per 280 mm of the roll width is preferably 5 g or more and 22 g or less, more preferably 7 g or more and 17 g or less, and even more preferably 9 g or more and 13 g or less.

[0045] (Specific volume) The specific volume of the kitchen towel sheet 1x is 7 cm 322 cm or more per g 3 per g or less. When the specific volume of the kitchen towel sheet 1x is less than 7 cm 3 per g, it is difficult to follow the shape of the object and difficult to wipe, and when it exceeds 22 cm 3 per g, the water absorption of the kitchen towel sheet 1x tends to be low. The specific volume is preferably 20 cm 3 or more per g and 9 cm 3 or less per g, more preferably 17 cm 3 or more per g and 12 cm 3 or less per g. The specific volume is obtained by dividing the paper thickness per 2 plies of the kitchen towel sheet 1x by the basis weight per 2 plies, and is expressed as the volume cm per unit g 3 .

[0046] (DMDT and DCDT) The dry machine direction tensile strength DMDT (Dry Machine Direction Tensile Strength) of 2 plies of the kitchen towel sheet 1x based on JIS P 8113 is preferably 4.5 N / 25 mm or more and 21 N / 25 mm or less, and the dry cross direction tensile strength DCDT (Dry Cross Direction Tensile Strength) is preferably 4.5 N / 25 mm or more and 21 N / 25 mm or less. When DMDT or DCDT is less than 4.5 N / 25 mm, the kitchen towel sheet 1x is likely to fuzz and tear when absorbing water, making it difficult to wipe. When DMDT or DCDT exceeds 21 N / 25 mm, the kitchen towel sheet 1x becomes hard and difficult to wipe. Note that DMDT is more preferably 6.0 N / 25 mm or more and 17.0 N / 25 mm or less, and even more preferably 7.5 N / 25 mm or more and 12.0 N / 25 mm or less. Also, DCDT is more preferably 6.0 N / 25 mm or more and 17.0 N / 25 mm or less, and even more preferably 7.5 N / 25 mm or more and 12.0 N / 25 mm or less. Also, 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 still more preferably 1.0 or more and 1.2 or less.

[0047] (WMDT and WCDT) Also, for the two-ply kitchen towel sheet 1x, the wet machine direction tensile strength WMDT (Wet Machine Direction Tensile Strength) based on the former 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 (Wet Cross Direction Tensile Strength) is preferably 1.5 N / 25 mm or more and 8.0 N / 25 mm or less. If either WMDT or WCDT is less than 1.5 N / 25 mm, the kitchen towel sheet 1x is likely to fuzz and tear when absorbing water, and it becomes difficult to wipe. If either WMDT or WCDT exceeds 8.0 N / 25 mm, the kitchen towel sheet 1x becomes hard and difficult to wipe. Incidentally, WMDT is more preferably 2.0 N / 25 mm or more and 6.0 N / 25 mm or less, and still more preferably 2.5 N / 25 mm or more and 4.5 N / 25 mm or less. Also, WCDT is more preferably 2.0 N / 25 mm or more and 6.0 N / 25 mm or less, and still more preferably 2.5 N / 25 mm or more and 4.5 N / 25 mm or less. Also, 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 still more preferably 1.0 or more and 1.2 or less.

[0048] (Ply peel strength) The ply peeling 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 peeling strength is less than 0.04 N / 75 mm, the plies are likely to peel off during wiping, making it difficult to wipe. If the ply peeling strength exceeds 2.1 N / 75 mm, the water absorption of the kitchen towel sheet 1x tends to be low. In addition, the ply peeling 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 even more preferably 0.15 N / 75 mm or more and 0.6 N / 75 mm or less. The method for measuring the ply peeling strength can be carried out using a tensile testing machine (STB-1225S, manufactured by A&D Company, Limited) in accordance with the tensile test method of JIS P 8113 under the standard conditions specified in JIS P 8111. First, a test piece with a width of 75 mm in the width direction and a length of 200 mm in the flow direction is taken from a sample of the kitchen towel roll 1. Next, the ply is peeled 35 mm in the flow direction. One side of the peeled ply is fixed by sandwiching it with the upper gripper (width 75 mm) for 15 mm in the flow direction. Also, the other ply is fixed by sandwiching it with the lower gripper (width 75 mm) for 15 mm in the flow direction. The pitch (interval) of the grippers is set to 20 mm. Next, the ply is pulled (peeled) under the condition of a pulling speed of 100 mm / min, and the strength data is collected. The data is acquired every 20 μm, and the data from 40 mm to 150 mm (measurement length 110 mm) after the start of measurement is averaged, and this is taken as the peeling strength (N / 75 mm). However, if the perforation is included from 40 mm to 150 mm after the start of measurement, the distance after the start of measurement can be shortened to a range without perforation, for example, from 40 mm to 90 mm (measurement length 50 mm).

[0049] (Manufacturing method of kitchen towel sheet and kitchen towel roll) 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 through-air dryer technology. At this time, in the papermaking process, a pattern of irregularities derived from a papermaking process (fabric) different from the above-described embossing pattern is applied to the kitchen towel sheet 1x. By having this pattern of irregularities, the water absorption of the kitchen towel sheet 1x becomes even higher. Note that being derived from the papermaking process means that it is applied between the headbox of the paper machine and the inlet of the Yankee dryer in the papermaking process of the kitchen towel sheet 1x. In particular, the irregularities are formed when the sheet is dried together with the fabric in the through-air dryer section. Also, the pattern of irregularities can be appropriately changed by changing the pattern of the fabric (fine pattern, rough pattern). When the pattern of irregularities is changed, the specific volume (paper thickness) changes, but it is preferable to select a pattern such that the specific volume (paper thickness) of the base paper is within the numerical range described later. Also, it is preferable to select a pattern such that the root mean square height Sq of the surface roughness of the non-embossed portion of the kitchen towel sheet 1x is within the above-described numerical range.

[0050] When using the base paper made by papermaking using this through-air dryer, it is preferable that the area ratio of the convex portions on the embossing roll for applying the embossing pattern is 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 likely to be torn during wiping. If the area ratio exceeds 40%, the kitchen towel sheet 1x is likely to be crushed and its water absorption is likely to decrease. Note that the area ratio of the convex portions is more preferably 6% or more and 30% or less, and even more preferably 9% or more and 18% or less. Also, the shapes of the convex portions and the embossing alone can be used without particular limitation, such as circular, elliptical, rectangular, square, floral pattern, logo, characters, etc., but linear embossing is preferable as described above. This embossing is preferably provided only on the surface 1a of the kitchen towel sheet 1x as described above.

[0051] At this time, the basis weight of the two-ply base paper used for manufacturing the kitchen towel sheet 1x (which is twice the basis weight of one ply) is preferably 31 g / m 2 or more and 58 g / m 2 or less, more preferably 35 g / m 2 or more and 54 g / m 2 or less, and even more preferably 39 g / m 2 or more and 50 g / m 2 or less. Also, the paper thickness 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 preferably 7 cm 3 / g or more and 22 cm 3 / g or less, more preferably 9 cm 3 / g or more and 20 cm 3 / g or less, and even more preferably 12 cm 3 / g or more and 17 cm 3 / g or less.

[0052] In addition, the ratio of the embossing depth in the embossing pattern to the paper thickness of the base paper of the kitchen towel sheet 1x, i.e., the ratio of the embossing depth in the embossing pattern / the paper thickness of the base paper of the kitchen towel sheet 1x, is preferably 0.01 or more and 0.38 or less, more preferably 0.03 or more and 0.33 or less, and even more preferably 0.07 or more and 0.18 or less. By setting it within this range, in the case of the kitchen towel sheet 1x with good water absorption as in the present application, it is not bulky, the ply peeling is difficult, and the water absorption can be improved. Also, 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 - the specific volume of the base paper) is preferably -3 cm 3 / g or more and 2 cm 3 / g or less, more preferably -2 cm 3 / g or more and 1 cm 3 / g or less, and even more preferably -1 cm 3 / g or more and 0.5 cm 3More preferably, it is below / g, and -0.5 cm 3 Above / g and 0 cm 3 Particularly preferably, it is below / g.

[0053] The present invention is not limited to the above-described embodiments, and it goes without saying that the present invention extends to various modifications and equivalents included in the spirit and scope of the present invention.

Examples

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

[0055] For the manufactured kitchen towel sheets and kitchen towel rolls, evaluation was conducted on the following items. Tearing and fuzzing of the surface layer: When the monitor used one kitchen towel sheet, the difficulty of tearing and fuzzing of the surface layer was evaluated. Water absorbency: When the monitor used one kitchen towel sheet, the remaining water after wiping was evaluated. Wiping property: When the monitor used one kitchen towel sheet, the ease of wiping work was evaluated.

[0056] Regarding the above three items, 20 monitors selected "good" or "bad" for each evaluation item. The evaluation criteria were as follows, and ◎, ○, and △ were considered passing. ◎: When "good" is 18 or more and 20 or less people ○: When "good" is 14 or more and 17 or less people △: When "good" is 10 or more and 13 or less people ×: When "good" is 6 or more and 9 or less people ××: Is there no "good"? When it is one or more and five or less people

[0057] The obtained results 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 absorption and bulkiness, and the surface layer is not easily torn during wiping and is easy to wipe.

Explanation of Signs

[0060] 1 Kitchen towel roll 1a Surface 1b Back surface 1e Edge of the outermost roll of the kitchen towel sheet 1x Kitchen towel sheet 200 Test piece 200a, 200d Corners 210 Band 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 kitchen towel roll is characterized in that the root mean square height of surface roughness in the portion not provided with the embossed pattern is 35 μm or more and 170 μm or less.

2. In the embossing pattern, for embossments having a thickness of 0.1 mm to 4 mm and a length of 5 mm or more, the total length of the embossments added together is 50 cm / 100 cm. ２ More than 550cm / 100cm ２ 2. The kitchen towel roll of claim 1, characterized in that:

3. 3. 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.

4. 4. The kitchen towel roll according to claim 1, wherein 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.

5. 5. 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.

6. 1m between the two plies of the kitchen towel sheet ２ 6. 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.

7. 7. 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.

Images