JP7798482B2 - Kitchen Towel Roll Products - Google Patents

Description

The present invention relates to a kitchen towel roll product.

Kitchen towels are widely used for cleaning kitchen appliances such as microwave ovens and stoves, draining and wiping dishes, removing moisture from raw vegetables, meat, fish, and other ingredients, and draining oil from fried foods, and these uses require them to have sufficient water and oil absorption capacities. For this reason, various bulky papermaking technologies have been proposed to increase the water and oil absorption capacities of kitchen towels.

Patent Document 1 discloses a kitchen towel comprising a single sheet or two or more stacked sheets of pulp-based material, each set having a basis weight of 15 g/ ^m² to 50 g/ ^m² and an oil absorption/basis weight of 4.5 OIL-g/g to 7.5 OIL-g/g (claim 1). Furthermore, when the length of the measurement field of view, excluding embossing performed in mechanical processes other than the paper machine, is 1.0 mm to 1.4 mm, the height difference of the surface irregularities is 100 μm to 600 μm (claim 3, paragraphs 0021 and 0022). The surface depression area ratio measured under conditions of a scan area of 10 cm x 10 cm is 2% to 12% (claim 4, paragraph 0023). Patent Document 1 also discloses a method for producing a kitchen towel, which involves pressing an irregularity-imparting fabric against a wet paper web to impart irregularities while dewatering, and then drying the wet paper web (claim 6). According to Patent Document 1, a kitchen towel is provided that is made primarily of pulp and has a high oil absorption capacity even though it has a low basis weight.

Patent Document 2 discloses a tissue papermaking apparatus for producing high-bulk tissue paper. The apparatus has a press section that presses and textures a wet fibrous web, and the press section includes a texture belt having a texture layer. The texture layer is nonwoven and has a web-carrying side with a surface that cooperates with the fibrous web, and the surface has depressions or raised portions that form a three-dimensional structure (Claim 1). Patent Document 2 also describes that high-bulk tissue paper is provided that has a bulk of at least 8 ^cm3 /g to 20 ^cm3 /g and can be produced at low energy cost using press technology (Paragraph 0013).

International Publication No. WO2014/041681 Special Publication No. 2011-506780

Kitchen towels are generally used in the form of kitchen roll towels, which are wound into a roll. However, when bulky kitchen towels are wound into a roll, there is a problem in that the roll tends to loosen. When loosely wound kitchen roll towels are packaged, poor sealing and scorching (holes caused by burning) occur, reducing the aesthetic appeal of the package and increasing the rate of defective products. Tightly rolling the kitchen towels improves the packaging, but the kitchen towels are crushed, reducing their absorbency and eliminating the benefits of bulky papermaking technology.

On the other hand, by increasing the basis weight of the kitchen towel excessively and tightly winding it, it is possible to achieve both aesthetic packaging and the absorbency of the kitchen towel, but this leads to other problems such as higher manufacturing costs and the paper quality of the kitchen towel becoming harder, reducing wiping properties.

Kitchen roll towels are also packaged in a packaging resin film and sold commercially as kitchen roll towel products. While various packaging styles are known, caramel packaging is the most commonly used style, as it improves the aesthetic appeal of kitchen roll towel products and allows more kitchen roll towel products to fit into a single cardboard shipping box without collapsing. However, caramel packaging presents additional problems: if the kitchen towels are wrapped loosely, the aesthetic appeal of the packaging is diminished, and if they are wrapped tightly, the absorbency of the kitchen towels is reduced.

The object of the present invention is to provide a kitchen roll towel product that combines high levels of absorbency and wiping ability, provides a pleasant feel when in use, and is packaged at low cost with excellent decorative properties.

As a result of extensive research to solve the above-mentioned problems, the inventors discovered that a kitchen roll towel product that meets the objectives can be obtained by winding up a softer kitchen towel than conventional ones, with basis weight, water absorption, and specific volume each set within a predetermined range, into a roll at a predetermined roll density, and then caramel-wrapping it in a packaging resin film, leading to the completion of the present invention. Specifically, the present invention relates to the kitchen roll towel product described below.

(1) A kitchen roll towel product,
a kitchen roll towel obtained by winding up a sheet-shaped kitchen towel that is a two-ply laminate having an embossed pattern into a roll;
a packaging film for packaging the kitchen roll towel;
The kitchen towel is
The paper has a paper machine-derived uneven pattern provided between the head box of the paper machine and the inlet of the Yankee dryer,
The basis weight is 30 g/m ² or more and 54 g/m ² or less, the water absorption is 200 g/m ² or more and 600 g/m ² or less, and the specific volume is 8 cm ³ /g or more and 20 cm ³ /g or less,
The kitchen roll towel product has a roll density of 0.04 g/cm ³ or more and 0.15 g/cm ³ or less.
(2) The kitchen roll towel product according to (1) above, which is a caramel-wrapped product of one or more of the kitchen roll towels wrapped in the packaging film.
(3) The kitchen roll towel product of (1) or (2) above, wherein the DMDT/DCDT ratio of the kitchen towel is 0.8 or more and 2.0 or less, and the DMDT is 4N/25mm or more and 16N/25mm or less, and the DCDT is 3N/25mm or more and 13N/25mm or less.
(4) A kitchen roll towel product according to any one of (1) to (3) above, wherein the kitchen towel further has a plurality of perforations extending in the width direction thereof to cut the kitchen towel in the width direction, the plurality of perforations are arranged at predetermined intervals in the longitudinal direction, and the area of the kitchen towel piece surrounded by two adjacent perforations in the longitudinal direction is 0.02 ^m2 or more and 0.10 ^m2 or less.
(5) The kitchen towel roll product according to any one of (1) to (4) above, wherein the kitchen towel has a ply peel strength of 0.01 N/75 mm or more and 1.5 N/75 mm or less.
(6) A kitchen towel roll product according to any one of (1) to (5) above, wherein the roll diameter of one roll of the kitchen roll towel is 113 mm or more and 200 mm or less.
(7) A kitchen towel roll product according to any one of (1) to (6) above, wherein the kitchen towel further has an embossed pattern different from the uneven pattern derived from the paper machine, and the area ratio of the convex portions on the embossing roll for applying the embossed pattern is 4% or more and 40% or less.
(8) The kitchen towel roll product according to (7) above, wherein the embossed pattern is a linear embossed pattern.
(9) The kitchen towel roll product according to (8), wherein the linear embossed pattern has a thickness of 0.1 mm or more and 4 mm or less, a length of 5 mm or more, and a total length including the length of the embossments is 50 cm/100 ^cm2 or more and 550 cm/100 ^cm2 or less.
(10) A kitchen towel roll product according to any one of (7) to (9) above, wherein the root mean square height of the surface roughness of the kitchen towel in the portion not provided with the embossed pattern is 35 μm or more.
(11) The kitchen towel roll product according to any one of (1) to (10) above, wherein the packaging film has heat sealing properties.
(12) A kitchen towel roll product according to any one of (1) to (11) above, wherein the thickness of the packaging film is 15 μm or more and 40 μm or less.

The present invention provides a kitchen roll towel product that combines high levels of absorbency and wiping ability, provides a pleasant feel when in use, and is packaged at low cost with excellent decorative properties.

1 is a perspective view schematically illustrating the external configuration of a kitchen roll towel product according to an embodiment of the present invention. FIG. 2 is a perspective view schematically showing the appearance of a kitchen roll towel in the kitchen roll towel product shown in FIG. 1. FIG. 2 is a schematic diagram illustrating how to determine the embossed area of the kitchen towel in the kitchen roll towel product shown in FIG. 1. FIG. 1 is a schematic diagram showing a height profile on an XY plane as viewed through a microscope, using shading. 1 is a graph of a height profile on an XY plane obtained by a microscope. FIG. 1 is a schematic diagram illustrating how to determine the depth of an embossment having an area of 1 mm ² or more and 40 mm ² or less. FIG. 2 is a schematic diagram illustrating a method for measuring the water absorption of the kitchen towel in the kitchen roll towel product shown in FIG. 1. FIG. 2 is a schematic diagram showing a part of the papermaking process for the kitchen towel in the kitchen roll towel product shown in FIG. 1. FIG. 10 is a schematic plan view showing a specific example of a linear embossing pattern. FIG. 10 is a diagram showing the height profile of a non-embossed portion on the XY plane as viewed under a microscope, using gray scales.

A kitchen roll towel product 1 of this embodiment will now be described with reference to the drawings. FIGS. 1 and 2 show a kitchen roll towel product (hereinafter also simply referred to as "product") 1 and a kitchen roll towel (hereinafter also simply referred to as "roll") 2, respectively. FIGS. 3 and 7 show a method for determining the embossed area of a kitchen towel 11x and a method for measuring the amount of water absorption, respectively. FIGS. 4 and 5 show a height profile on the X-Y plane obtained using a microscope. FIG. 6 shows a method for determining the depth of an embossment unit having an area of 1 ^mm2 or more and 40 ^mm2 or less. FIG. 8 shows a portion of the papermaking process for a kitchen towel 11x. FIG. 9 shows a linear embossed pattern. FIG. 10 shows a non-embossed portion.

<Kitchen roll towel products>
The kitchen roll towel product 1 of this embodiment is a two-ply laminate with an embossed pattern. The embossed pattern is derived from the papermaking machine and is applied between the head box and the Yankee dryer inlet. The sheet-like (or strip-like) kitchen towel 11x has a basis weight of 30 g/ ^m² to 54 g/ ^m² , a water absorption capacity of 200 g/ ^m² to 600 g/ ^m² , and a specific volume of 8 ^cm³ /g to 20 ^cm³ /g. The sheet-like (or strip-like) kitchen towel 11x is wound around a core ¹⁰ , such as a paper tube or plastic tube, so that the roll density is 0.04 g/ ^cm³ to 0.15 g/cm³. The resulting kitchen roll towels 2 are then aligned lengthwise and placed side by side in two rows, wrapped in a packaging film 20, to form a caramel-wrapped product. While the packaging form of the kitchen roll towel product 1 is preferably a caramel-wrapped product, this is not limited thereto and various packaging forms of currently commercially available products can also be used. Furthermore, the number of kitchen roll towels 2 to be packaged is not limited to this embodiment and may be one, three, or more. The embossed pattern of the kitchen towel 11x includes a paper machine-derived uneven pattern (embossed pattern) that is automatically applied between the head box of the paper machine and the entrance of the Yankee dryer, as well as other embossed patterns, for example, as described below.

One caramel packaging is not limited to this embodiment and may contain one roll 2 or three or more rolls 2. When packaging multiple rolls 2, two or three rolls 2 are preferred from the perspective of packaging aesthetics. By packaging the rolls 2 in caramel, sealing defects and scorch (holes caused by burning) are less likely to occur, significantly improving the aesthetic appeal of the packaging. Furthermore, caramel packaging provides excellent strength and ease of opening.

According to this embodiment, by adjusting three specific properties of the two-ply laminate having an embossed pattern derived from a paper machine, namely, basis weight, water absorption, and specific volume, within respective predetermined ranges, a kitchen towel 11x can be obtained that has high levels of water absorbency, oil absorbency, wiping ability, etc., while also having a soft paper quality not previously available. A roll 2 obtained by winding such kitchen towel 11x at a predetermined roll density is less likely to loosen, and does not suffer from poor sealing or scorching (holes caused by burning) even when packaged, resulting in a highly decorative package. Furthermore, even without tightly winding, it is possible to achieve both a decorative package and the absorbency of the kitchen towel at low manufacturing costs, and a high level of decorative package quality can be maintained even when packaged in caramel.
Each component of the kitchen roll towel product 1 will be specifically described below.

<Kitchen towel>
As described above, the kitchen towel 11x of this embodiment is a two-ply laminate having a papermaking machine-derived uneven pattern applied between the head box of the papermaking machine and the entrance of the Yankee dryer. In the kitchen towel 11x, an adhesive layer may be provided between the plies to prevent ply peeling. The adhesive layer may be provided over the entire surface between the plies or only a portion of the surface. Any known adhesive that does not affect the water absorption or texture of the kitchen towel 11x can be used without particular limitation, such as glue. The kitchen towel 11x may or may not have a print. In the following description, the surface of the kitchen towel sheet 11x facing the outside of the roll 2 shown in FIG. 2 is referred to as the front surface 11a, and the surface facing the core 10 of the roll 2 is referred to as the back surface 11b.

(Basic weight)
The kitchen towel 11x of this embodiment has a basis weight of 30 g/ ^m2 or more and 54 g/ ^m2 or less, preferably 34 g/ ^m2 or more and 50 g/ ^m2 or less, and more preferably 38 g/ ^m2 or more and 46 g/ ^m2 or less. If the basis weight is less than 30 g/ ^m2 , the feel of the kitchen towel 11x during use tends to deteriorate. If the basis weight exceeds 54 g/ ^m2 , the kitchen towel 11x becomes stiff and does not conform to the shape of the object, which tends to reduce wiping performance. The basis weight is measured based on JIS P 8124.

(Water absorption amount)
The kitchen towel 11x has a water absorption capacity of 200 g/ ^m2 or more and 600 g/ ^m2 or less, preferably 300 g/ ^m2 or more and 500 g/ ^m2 or less, and more preferably 350 g/ ^m2 or more and 450 g/ ^m2 or less. Here, in the units of water absorption, "g" indicates the weight of water absorbed by the kitchen towel 11x, and " ^m2 " indicates the area of the kitchen towel 11x that has absorbed water. When the kitchen towel 11x is cut into sheets of a size that is easy to handle, if the water absorption capacity is less than 200 g/ ^m2 , the ability to wipe off water tends to decrease, and if the water absorption capacity exceeds 600 g/ ^m2 , the sheet of that size cannot be used effectively, and must be discarded even though there is still water absorption capacity.

(Method for measuring water absorption)
The measurement of the water absorption amount is carried out, for example, in the following order (a) to (c).
(a) Two layers of kitchen towel 11x are taken and cut using a square template with each piece measuring 7.6 cm (3 inches) to prepare a rectangular test piece with a side length of 7.6 cm. The mass of the test piece before water absorption is measured using an electronic balance. The test piece is set in the holder shown in Figure 7 (a jig that fixes three points of the test piece, made of a metal that does not absorb water).
(b) Distilled water is poured into a commercially available tray to a depth of 2 cm, and the test piece set in the holder is immersed in the distilled water for 2 minutes. After immersion for 2 minutes, the test piece and holder are removed from the distilled water, and a band 210 is attached to one corner 200d of the test piece 200 as shown in Figure 7. The band 210 is made by cutting the same kitchen towel 11x as the sample to be measured into a size of 2 mm wide x 15 mm long, and attaching it to a section 6 mm from the corner 200d toward the center of the test piece.
(c) The holder 220 and test piece 200 are hung from a rod placed in an empty water tank with the corner 200a opposite the corner 200d facing up, the lid of the water tank is closed, and the test piece 200 is left for 10 minutes. The holder 220 and test piece 200 are then removed from the water tank, the band 210 and holder 220 are removed, and the mass of the test piece 200 is measured using an electronic balance. The amount of distilled water absorbed per 1 ^m2 of test piece (g of water/ ^m2 of paper) is calculated from the change in mass of the test piece 200 before and after immersion in distilled water. Measurements are made five times for each sample, and the average value is used.
The measurement is carried out in accordance with 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.

(specific volume)
The kitchen towel 11x of this embodiment has a specific volume of 8 cm ³ /g or more and 20 cm ³ /g or less, preferably 10 cm ³ /g or more and 18 cm ³ /g or less, and more preferably 12 cm ³ /g or more and 16 cm ³ /g or less. If the specific volume is less than 8 cm ³ /g, water absorbency tends to decrease, and if the specific volume exceeds 20 cm ³ /g, strength tends to decrease and the towel tends to tear easily. The specific volume is the value obtained by dividing the paper thickness of the kitchen towel (2-ply laminate) 11x by the basis weight, and is expressed as a volume in cm ³ per unit g. The basis weight, water absorption, specific volume, etc. can be adjusted within a predetermined range by, for example, appropriately adjusting the beating conditions of the raw material, the calendering conditions of the base paper web, the creping conditions, the embossing conditions, etc.

In a preferred embodiment, the kitchen towel 11x has the following physical properties and/or configuration in addition to the physical properties described above.

(DMDT and DCDT)
DMDT (Dry Machine Direction Tensile Strength, hereinafter also referred to as "dry longitudinal strength") refers to the tensile strength of the kitchen towel 11x in the longitudinal direction when dry based on JIS P 8113. From the viewpoint of wiping performance, for example, it is in the range of 4 N/25 mm to 16 N/25 mm, 5 N/25 mm to 13 N/25 mm, or 6 N/25 mm to 10 N/25 mm. If DMDT is in the above-mentioned range, the soft feel of the kitchen towel 11x is fully exhibited, and wiping performance is improved. DCDT (Dry Cross Direction Tensile Strength, hereinafter also referred to as "dry cross direction strength") refers to the tensile strength of the kitchen towel 11x in the cross direction when dry based on JIS P 8113, and from the viewpoint of wiping performance, etc., is, for example, in the range of 3 N/25 mm to 13 N/25 mm, 4 N/25 mm to 13 N/25 mm, or 5 N/25 mm to 10 N/25 mm. If the DCDT is within the above range, the soft feel of the kitchen towel 11x is fully exhibited, and wiping performance is improved. If the DMDT is less than 4 N/25 mm and/or the DCDT is less than 3 N/25 mm, the kitchen towel 11x tends to tear easily when absorbing water, resulting in reduced wiping properties. If the DMDT is more than 16 N/25 mm and/or the DCDT is more than 13 N/25 mm, the kitchen towel 11x tends to become denser, absorbency is reduced, and the paper becomes more solid, resulting in reduced wiping properties. The DMDT/DCDT ratio is, for example, in the range of 0.8 to 2.0, 0.9 to 1.8, or 1.0 to 1.6. By setting the DMDT/DCDT ratio within the aforementioned range, the kitchen towel 11x has a soft and comfortable feel. If the DMDT/DCDT ratio is less than 0.8, the sheet tends to tear easily when torn along the perforations, and if the DMDT/DCDT ratio exceeds 2.0, the feel when used tends to change depending on the wiping direction. DMDT and DCDT can be adjusted, for example, by the jet/wire ratio, machine speed, raw material discharge angle, etc.

(perforation)
In a preferred embodiment, the kitchen towel 11x further has multiple perforations (not shown) extending widthwise and cutting the kitchen towel 11x widthwise. The multiple perforations are spaced apart longitudinally at predetermined intervals, and the area of a single kitchen towel piece enclosed by two adjacent perforations in the longitudinal direction (hereinafter also referred to as the "sheet area") is in the range of 0.02 ^m2 to 0.10 ^m2 , 0.03 ^m2 to 0.08 ^m2 , or 0.04 ^m2 to 0.06 ^m2 . This kitchen towel piece can also be described as a sheet cut along two adjacent perforations in the longitudinal direction. Rather than setting the sheet area alone, it is necessary to set it in conjunction with the characteristics of the kitchen towel 11x, particularly the basis weight, water absorption capacity, and specific volume. In this embodiment, by setting the optimal water absorption capacity, oil absorption capacity, etc. for a sheet area with good wiping properties, a highly convenient kitchen towel piece can be created. If the area of the kitchen towel piece is less than 0.02 ^m2 , it tends to be difficult to wipe off the object to be wiped, or one kitchen towel piece may not be able to wipe off the object sufficiently. If the area exceeds 0.10 ^m2 , the kitchen towel piece will often be discarded while there is still room for water or oil absorption, and one kitchen towel piece will not tend to be used effectively.

(Ply Peel Strength)
The ply peel strength of the kitchen towel 11x is, for example, in the range of 0.01 N/75 mm to 1.5 N/75 mm, 0.03 N/75 mm to 1.3 N/75 mm, or 0.05 N/75 mm to 1.0 N/75 mm. Setting the ply peel strength within the above range makes it easier to adjust the roll density within the range specified in this embodiment. If the ply peel strength is less than 0.01 N/75 mm, the plies tend to peel off from each other, making wiping difficult. If the ply peel strength exceeds 1.5 N/75 mm, the water absorption capacity of the kitchen towel 11x tends to decrease.

Measurements of ply peel strength are performed in accordance with the tensile test method of JIS P 8113 using a tensile testing machine (STB-1225S, manufactured by A&D Co., Ltd.) under the standard conditions specified in JIS P 8111. First, a test piece measuring 75 mm in the width direction and 200 mm in the machine direction is taken from a kitchen towel 11x sample. Next, the ply is peeled 35 mm in the machine direction. One side of the peeled ply is clamped 15 mm in the machine direction between upper grips (75 mm wide). The other ply is also clamped 15 mm in the machine direction between lower grips (75 mm wide). The grip pitch (spacing) is 20 mm. Next, the sample is pulled (peeled) at a pulling speed of 100 mm/min, and strength data is collected. Strength data is obtained every 20 μm, and the data from a distance of 40 mm to 150 mm after measurement begins (measurement length 110 mm) 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 measurement begins, the distance after measurement begins can be shortened from 40 mm to, for example, 90 mm (measurement length 50 mm), as long as it does not include the perforation.

(embossed pattern)
The kitchen towel 11x may have an embossed pattern different from the uneven pattern derived from the papermaking machine, in addition to the uneven pattern. Such an embossed pattern can be easily formed, for example, by processing using an embossing roll having convex portions on the peripheral surface of the roll (hereinafter also referred to as "embossing"). The area ratio of the convex portions on the embossing roll [(total area of the convex portions surfaces/total surface area of the embossing roll) x 100] is, for example, in the range of 4% to 40%, 6% to 30%, or 9% to 18%. By setting the area ratio of the convex portions on the embossing roll within the above-mentioned range, it is easy to adjust the ply peel strength within a preferred range. If the area ratio of the convex portions is less than 4%, the plies tend to peel off from each other, making wiping difficult, while if it exceeds 40%, water absorbency tends to decrease. Furthermore, the kitchen towel 11x of this embodiment may be formed by embossing a single-ply sheet and then laminating two plies together. When laminating two plies together, it is preferable to apply a ply bond glue (adhesive) to the ply bonded sheet. By bonding the two plies together in this way, the plies are more strongly bonded together, making the kitchen towel 11x less likely to tear even when wet. The embossed shape is also more likely to be maintained, allowing for good appearance, absorbency, and wiping properties.

The ply on the front surface 11a of the kitchen towel 11x has, for example, a dot-shaped embossed pattern or a line-shaped embossed pattern. When a dot-shaped or line-shaped embossed pattern is applied to the front surface 11a, the embossed portions of the embossed pattern can be applied with glue for adhesion, making the ply of the kitchen towel 11x less likely to peel off and suppressing large fluctuations in water absorption. Furthermore, there are no particular restrictions on whether the ply on the back surface 11b of the kitchen towel 11x has an embossed pattern, as long as it has a different, uneven pattern derived from the papermaking process than the embossed pattern. It may have nested embossing or pin-to-pin embossing, or it may not have embossing; however, nested embossing or no embossing is preferred, and no embossing is more preferred.

In a preferred embodiment, the embossed pattern is a linear embossed pattern, from the perspective of ease of setting the numerical value of the ply peel strength. The linear embossed pattern is not particularly limited, as long as it includes two of two types of figures, one of which is a roughly circular figure with another pattern inside it, and the other is a figure that is roughly line-symmetrical both vertically and horizontally as a whole and includes a combination of multiple curves and figures, as shown in Figure 9. In a more preferred embodiment, the roughly circular figure has two roughly circular figures.

In a linear embossing pattern, the total length of all embossments that are 0.1 mm to 4 mm thick and 5 mm or longer (total length of all embossments having the aforementioned dimensions) is, for example, in the range of 50 cm/100 ^cm2 to 550 cm/100 ^cm2 , 80 cm/100 ^cm2 to 410 cm/100 ^cm2 , or 110 cm/100 ^cm2 to 300 cm/100 ^cm2 . By setting the total length within the aforementioned range, it becomes easier to adjust the ply peel strength to an appropriate range, for example.

The total length is measured as the sum of the lengths of all embossments with a thickness of 0.1 mm to 4 mm and a length of 5 mm or more within a rectangle E that includes all of the embossed patterns, as shown in Figure 9, and is taken as the total length per 100 ^cm2 . The size of one side of this rectangle E can be changed as appropriate depending on the size of the embossed pattern. If the rectangle that includes all of the embossed patterns includes an embossed pattern adjacent to an embossed pattern included within the rectangle, the length of that 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 based on the embossed pattern, the size of the rectangle E is set to 10 cm x 10 cm, and the total length of the embossments included in this rectangle E is measured. By keeping the total length within the above range, the highly absorbent kitchen towel 11x of this embodiment is less likely to peel off the ply and has excellent wiping properties. The total length is determined by actual measurement using the method described above. Measurement may also be performed using a conventional microscope.

In the embossing pattern, the embossing depth is, for example, in the range of 0.06 mm to 1.1 mm, 0.10 mm to 0.80 mm, or 0.20 mm to 0.55 mm. If the embossing depth is less than 0.06 mm, the plies tend to peel off easily in kitchen towel 11x with high water absorption capacity, such as in this embodiment. If the embossing depth exceeds 1.1 mm, the specific volume of kitchen towel 11x increases, and it tends to be difficult to improve water absorption capacity despite the bulkiness.

In the embossing pattern described above, an embossment having an area of 1 ^mm2 or more and 40 ^mm2 or less is defined as an embossment unit. The number of embossments per unit area of 100 ^cm2 in the embossing pattern is not particularly limited, but may be, for example, in the range of 20 to 1,800, 50 to 1,000, or 80 to 500. If the number of embossments is less than 20, the plies tend to peel easily in the case of a kitchen towel 11x with good absorbency such as that of this embodiment. If the number of embossments exceeds 1,800, the kitchen towel 11x tends to be crushed, resulting in a decrease in absorbency. Furthermore, the shape of the embossment unit may be circular, oval, rectangular, square, floral, or other shapes without particular limitations.

In the embossing pattern described above, the depth of each embossment having an area of 1 ^mm2 to 40 ^mm2 is, for example, in the range of 0.10 mm to 0.80 mm, 0.25 mm to 0.67 mm, or 0.35 mm to 0.55 mm. If the depth of the embossing unit is less than 0.10 mm, the kitchen towel 11x tends to have a low water absorption capacity and a poor feel when used. If the depth exceeds 0.80 mm, the kitchen towel 11x tends to be bulky, the roll density tends to be low, and the decorativeness of the package tends to be reduced.

The area and depth of the embossment are measured using a microscope. The microscope used is a KEYENCE One-Shot 3D Measuring Macroscope VR-3100. The microscope image observation, measurement, and image analysis software used is the VR-H1A. The measurement conditions are a magnification of 12x and a field of view of 24mm x 18mm. The measurement magnification and field of view may be changed as appropriate depending on the desired size of the embossment.

As shown in Figure 3, the area of an embossment is calculated by measuring the length a of the longest part of the embossment's peripheral edge fr and the length b of the longest part in the direction perpendicular to length a, and then calculating the product (a x b) of these. Figure 4 also shows a height profile on the X-Y plane taken with a microscope, with the height of the sheet surface represented by shading. The roughly elliptical areas in Figure 4 that are shaded differently from the surrounding area represent individual embossments, and the length a of the longest part of each embossment can be visually identified. The number of embossments per 100 ^cm2 is counted for embossment units with an area of 1 ^mm2 or more and 40 ^mm2 or less.

The number of embossments is measured visually by selecting an arbitrary 100 ^cm2 area from the entire area between two adjacent perforations in the longitudinal direction across the entire width of the sheet. If it is not possible to select an area of 100 cm2 because the ^sheet has been subjected to knurling (edge embossing) processing, for example, the number of embossments is measured in measurable areas excluding areas that cannot be measured due to knurling (edge embossing) processing, and this is converted into the number of embossments per 100 ^cm2 .

Next, the depth of the embossment is measured for each embossment unit having an area of 1 ^mm2 or more and 40 ^mm2 or less. The depth of the embossment is determined by measuring the height difference of the embossment using the microscope described above. First, a line segment AB is drawn as shown in Figure 4 to obtain the height profile shown in Figure 5. Note that line segment AB should be drawn so as to cross the embossment. The height profile is a (measured) cross-sectional curve S that represents the unevenness of the actual sheet sample surface, but it also contains noise (steep peaks due to the presence of fiber clumps on the sheet surface, fibers extending in a whisker-like pattern, or fiber-free areas), and such noise peaks must be removed when calculating the height difference of the unevenness.

As shown in Figure 6, a "contour curve" W is calculated from the cross-sectional curve S of the height profile. The difference between the average value of bottoms P1 and P2 and the apex between bottoms P1 and P2 is calculated, and this is defined as the emboss depth D1. Similarly, the difference between the average value of bottoms P2 and P3 and the apex between bottoms P2 and P3 is calculated, and this is defined as the emboss depth D2. Similarly, D3 is measured. Note that D1, D2, and D3 are measured at consecutive locations, as shown in Figure 6. This measurement is performed at 10 locations on the kitchen towel 11x, and the average of the data from a total of 30 locations is defined as the emboss depth. Note that if the distance between embosses (the distance between P1 and P2) is 1 cm or more, measurements may be performed at consecutive locations, but the difference between the average value of bottoms P1 and P2 and the apex between bottoms P1 and P2 is determined, and this is defined as the emboss depth D1. Alternatively, D1 may be measured at 30 locations and the average value defined as the emboss depth.

The "contour curve" is a curve obtained by using a low-pass filter to remove surface roughness components with wavelengths shorter than λc: 800 μm (λc is the "filter defining the boundary between roughness and waviness components" as described in JIS B 0601 "3.1.1.2") from the cross-sectional curve. Note that if λc is set to be greater than the distance between adjacent embossments P1 and P2, or P2 and P3 (this is called the emboss pitch), there is a risk that the peaks will be recognized as noise, so λc is set to be less than the emboss pitch. For example, if the emboss pitch is 800 μm or less, λc should be set to 250 μm.

When measuring the embossment, the measurement surface is the front side. When selecting the embossment, the measurement is made at a point that is 10% of the roll length of the roll 2 from the outer end of the roll 2 (the point where you start using the kitchen towel 11x). For example, if the roll length is 30m, the measurement is made at a point that is 30m x 10% = 3m from the end. Note that if the 10% portion of the roll length corresponds to a perforation, the measurement is made on the outer side of the perforation.

(non-embossed part)
In another preferred embodiment, the root mean square height Sq of the surface roughness of the portion of the kitchen towel 11x that does not have the embossed pattern (hereinafter also referred to as the "non-embossed portion") is, for example, in the range of 35 μm or more, 50 μm to 150 μm, 60 μm to 120 μm, or 70 μm to 90 μm. By setting the root mean square height Sq of the surface roughness of the non-embossed portion to 35 μm or more, for example, it becomes easy to adjust the water absorbency of the kitchen towel 11x to the appropriate range specified in this embodiment. If the root mean square height Sq of the surface roughness is less than 35 μm, the water absorbency tends to decrease. Furthermore, while there is no particular upper limit for the root mean square height Sq of the surface roughness, if the value is too high, the product may become bulky.

The root mean square height Sq of the surface roughness of the non-embossed portion is measured, for example, using a microscope. As with the embossing depth described above, the microscope used is the "One-Shot 3D Measuring Macroscope VR-3100" manufactured by KEYENCE Corporation, and the microscope image observation, measurement, and image analysis software is the "VR-H1A" product. Measurement conditions are a magnification of 38x and a field of view area of 8mm x 6mm. The measurement magnification and field of view area may be changed as appropriate depending on the desired size of the non-embossed portion.

For the image shown in Figure 10, filters are set in the same way as for the embossing depth described above. Specifically, an S-filter (low-pass filter) is set to remove components on a scale smaller than the cutoff wavelength from the image, and an L-filter (high-pass filter) is set to remove components on a scale larger than the cutoff wavelength. Here, the S-filter is set to 500 μm, and the L-filter is set to 8 mm. By selecting the S-filter and L-filter, the root-mean-square height Sq is automatically calculated.

For the non-embossed portion, remove three laps of kitchen towel 11x from roll 2 and use the fourth lap of kitchen towel 11x to measure the two-ply sheet. Also, if there are perforations, avoid these when measuring. Measure at two locations across the width of roll 2, then rotate roll 2 three times by 90 degrees in the machine direction of kitchen towel 11x, and measure in the same way as above at each position (for a total of four measurement locations in the machine direction). The average of these eight locations (2 x 4) is the root mean square height Sq.

(Roll length and paper thickness)
The roll length of the kitchen towel 11x is not particularly limited, but from the viewpoints of the frequency of replacement of the roll 2, ease of carrying and storing the product 1, etc., it is, for example, in the range of 20 m to 50 m, 25 m to 45 m, or 30 m to 40 m. The thickness (paper thickness) of the kitchen towel 11x is also not particularly limited, but from the viewpoints of ease of adjusting the basis weight and water absorption, strength, etc., it is, for example, in the range of 1.6 mm/10 plies to 4.7 mm/10 plies. The paper thickness is measured using a thickness gauge (a dial thickness gauge "PEACOCK (registered trademark)" manufactured by Ozaki Seisakusho Co., Ltd.). The measurement is performed with a measuring load of 3.7 kPa and a probe diameter of 30 mm. A sample is placed between the probe and the measuring table, and the gauge is read when the probe is lowered at a speed of 1 mm per second or less. Five sets of two-ply kitchen towels 11x are stacked to form 10 plies, and the measurement is performed. The measurement is repeated 10 times and the measurement results are averaged.

(WMDT and WCDT)
The wet machine direction tensile strength (WMDT) of the kitchen towel 11x, based on the former JIS S 3104, is, from the viewpoint of wiping performance, for example, in the range of 1.0 N/25 mm to 7.0 N/25 mm, 2.0 N/25 mm to 6.0 N/25 mm, or 2.5 N/25 mm to 5.0 N/25 mm. If the WMDT is within the above range, the towel will not tear and will be soft and easy to wipe. The wet cross direction tensile strength (WCDT) of the kitchen towel 11x, based on the old JIS S 3104, is, from the viewpoint of wiping performance, for example, in the range of 0.7 N/25 mm to 7.0 N/25 mm, 4.0 N/25 mm to 13.0 N/25 mm, or 5.0 N/25 mm to 10.0 N/25 mm. If the WCDT is within the above range, the kitchen towel 11x will not tear and will be soft and easy to wipe. If the WMDT is less than 1.0 N/25 mm and/or the WCDT is less than 0.7 N/25 mm, the kitchen towel 11x will be prone to tearing when absorbing water, and wiping performance will tend to be reduced. If the WMDT exceeds 7.0 N/25 mm and/or the WCDT exceeds 7.0 N/25 mm, the density of the kitchen towel 11x increases, and the wiping properties tend to decrease as the water absorbency decreases, or the towel tends to become hard and the wiping properties tend to decrease.

(sheet length)
The sheet length of the paper towel 11x in the width direction (CD direction) of the roll 2 is, for example, in the range of 180 mm to 350 mm, in the range of 200 mm to 340 mm, or in the range of 250 mm to 300 mm. By setting the CD direction length of the paper towel 11x within the above-mentioned range, the roll 2 can be easily removed. Furthermore, the length of the paper towel 11x in the MD direction (pitch) perpendicular to the CD direction is, for example, in the range of 160 mm to 330 mm, in the range of 180 mm to 305 mm, or in the range of 200 mm to 280 mm. By setting the MD direction length of the paper towel 11x within the above-mentioned range, the roll diameter is within an appropriate range.

(Material)
The kitchen towel 11x is primarily composed of wood pulp and may contain, as necessary, one or more of recycled paper pulp, non-wood pulp, deinked pulp, etc., within the range that does not impair the quality of the kitchen towel 11x. The kitchen towel 11x may also contain one or more of various additives.

Examples of wood pulp include NBKP (softwood kraft pulp) and LBKP (hardwood kraft pulp). NBKP can be any kraft pulp made from softwoods such as radiata pine, slash pine, southern pine, lodgepole pine, spruce, and Douglas fir. LBKP can be any kraft pulp made from hardwoods, but kraft pulp made from Eucalyptus genus (Myrtaceae), such as Eucalyptus grandis and Eucalyptus globulus, is preferred. Note that unbleached softwood pulp (NUKP) can be used instead of NBKP, and LUKP can be used instead of LBKP. The kitchen towel 11x of a preferred embodiment is composed of NBKP (softwood kraft pulp) and LBKP (hardwood kraft pulp). In this case, the ratio of NBKP to LBKP used is, for example, NBKP:LBKP = 25% by mass to 70% by mass to 30% by mass to 75% by mass, NBKP:LBKP = 35% by mass to 60% by mass to 40% by mass to 65% by mass, or NBKP:LBKP = 40% by mass to 55% by mass to 45% by mass to 60% by mass. Furthermore, by using a ratio of NBKP:LBKP = 10% by mass to 100% by mass to 0% by mass to 90% by mass, a kitchen towel 11x that satisfies the basis weight, water absorption, and specific volume specified in this embodiment can be easily obtained.

Examples of recycled paper pulp include pulp made from liquid beverage cartons (milk cartons, liquor cartons, etc.). Examples of non-wood pulp include synthetic fibers made from synthetic resins such as nylon, vinylon, polyester, acrylic, polyethylene, polypropylene, and polystyrene. Examples of deinked pulp include pulp made from recycled newspaper and magazine paper. When deinked pulp contains fluorescent dyes, the content of deinked pulp containing fluorescent dyes should be 20% by mass or less of the total pulp used. Examples of additives include softeners including debonder softeners, bulking agents, dyes, dispersants, dry strength agents, wet strength agents, drainage aids, pitch control agents, and absorbency improvers.

<Kitchen roll towel>
As shown in Figure 2, roll (kitchen roll towel) 2 is formed by winding kitchen towel 11x around core 10. There are no particular restrictions on the outer diameter D1 of core 10 of roll 2, but from the viewpoints of facilitating adjustment of the winding density of roll 2 and ease of handling of roll 2 during production, it is, for example, in the range of 35 mm to 45 mm, or 37 mm to 42 mm. The main characteristics of roll 2 are described below.

(Core outer diameter)
The core 10 is located at the center of the roll 2 and has a substantially circular cross section around which the paper towels 11x are wound. The roll 2 may have a paper tube inserted therein or may have a hollow portion. The core outer diameter is the outer diameter of the aforementioned core portion (paper tube, hollow portion, etc.). The core outer diameter is, for example, in the range of 30 mm to 60 mm, 34 mm to 55 mm, or 37 mm to 50 mm. According to this embodiment, a single product 1 can be wound with an amount of paper towels 11x that will not deteriorate during its use. Furthermore, the winding diameter of the roll 2 does not become larger than necessary. The roll width of the roll 2 is, for example, in the range of 180 mm to 350 mm, 210 mm to 325 mm, or 240 mm to 300 mm. The roll mass of the roll 2 is, for example, in the range of 160 g to 550 g, 230 g to 450 g, or 270 g to 380 g. The roll mass is the mass per 280 mm of roll width, excluding the core (paper tube) 10. If the roll width is not 280 mm, it is converted to the mass per 280 mm by proportional calculation.

(roll density)
The roll density of the roll 2 is in the range of 0.04 g/ ^cm3 to 0.15 g/ ^cm3 , preferably 0.06 g/ ^cm3 to 0.12 g/ ^cm3 , and more preferably 0.07 g/ ^cm3 to 0.09 g/ ^cm3 . Rather than setting the roll density range independently, it is necessary to set the roll density according to the basis weight, water absorption, and specific volume of the kitchen towel 11x. If the roll density is less than 0.04 g/ ^cm3 , the top and/or bottom surfaces of the product 1 cannot be neatly folded during caramel packaging, resulting in unbonded areas and scorching, which tends to impair the aesthetic appeal. If the roll density exceeds 0.15 g/ ^cm3 , the unevenness of the kitchen towel 11x tends to be crushed when the roll diameter is constant, resulting in a decrease in water absorption.

The roll density is expressed as {{cross-sectional area of the roll outer diameter (winding diameter DR)} - (cross-sectional area of the core outer diameter DI)} × roll width (converted per 280 mm). For example, if the roll mass per 280 mm of roll width is 327 g, the winding diameter DR is 122 mm, and the core outer diameter is 39 mm, the roll density = 327 g ÷ [{3.14 × (122 mm ÷ 2 ÷ 10) 2 - 3.14 × (39 mm ÷ 2 ÷ 10) 2} × (280 mm ÷ 10)] = 0.11 g/cm ^3. If the roll 2 does not have a core, the diameter of the central hole is replaced with the core outer diameter DI.

(reel diameter)
The roll diameter of the roll 2 per roll is, for example, in the range of 113 mm to 200 mm, 135 mm to 180 mm, or 140 mm to 160 mm. If the roll diameter is less than 113 mm, it tends to be difficult to adjust the roll density and the water absorption capacity of the kitchen towel 11x to a good balance within a favorable range. If the roll diameter exceeds 200 mm, the roll density and therefore the decorativeness of the package tend to decrease.

<Packaging film>
The product 1 is obtained by caramel-wrapping one or more rolls 2 in a packaging film 20. For example, a resin film having heat-sealing properties is used as the packaging film 20. The heat-sealing properties of the packaging film 20 allow packaging without the use of, for example, a hot-melt adhesive, thereby improving the aesthetic appearance of the resulting product 1. The packaging film 20 may be single-layered or multi-layered. The material for the packaging film 20 is preferably a thermoplastic resin. Thermoplastic resins have heat-sealing properties and are suitable for recycling. Specific examples of thermoplastic resins include polyolefin resins such as polyethylene and polypropylene, polyester resins such as PET, polyamides (trademark name nylon, etc.), polycarbonate, polystyrene, polyvinyl chloride, etc. Among these, polyethylene film is preferred.

The thickness of the packaging film 20 is, for example, in the range of 15 μm to 40 μm, 20 μm to 35 μm, or 25 μm to 30 μm. If the thickness is less than 15 μm, scorching may occur during heat sealing, reducing the aesthetic appeal and causing the packaging film 20 to tear. If the thickness exceeds 40 μm, the ease of opening the product 1 may be reduced. The packaging film 20 may or may not have perforations for opening the product 1.

<Method of manufacturing kitchen towel sheet and kitchen towel roll>
The kitchen towel sheet 11x and roll 2 can be manufactured, for example, in the following order: (1) papermaking and creping, (2) embossing, and (3) roll winding. The manufacturing process preferably uses through-air dryer technology. In this process, a textured pattern derived from the papermaking process (fabric), different from the embossing pattern described above, is applied to the kitchen towel 11x during the papermaking and creping processes. This textured pattern further increases the water absorption capacity of the kitchen towel 11x. Note that "originating from the papermaking process" refers to the texture being applied between the headbox of the papermaking machine and the entrance of the Yankee dryer during the papermaking process of the kitchen towel 11x. The textured pattern is formed by drying the sheet together with the fabric in the through-air dryer section. More specifically, the textured pattern can be applied in the belt press section 30, which is located between the dewatering roll 31 and the Yankee dryer 32, as part of the papermaking process shown in FIG. 8 . In the belt press section 30, the wet paper 34 and the uneven belt 33 (the uneven belt 33 loops through the belt press section 30 and the Yankee dryer 32) are pressed together to give the wet paper a pattern of unevenness.

The uneven pattern can be changed as needed by changing the fabric pattern (fine pattern, coarse pattern). Changing the uneven pattern will change the specific volume (paper thickness), but it is preferable to select a pattern that ensures that the specific volume (paper thickness) of the base paper falls within the numerical ranges described below. It is also preferable to select a pattern that ensures that the specific volume of the kitchen towel 11x and the root mean square height Sq of the surface roughness of the non-embossed portion fall within the respective numerical ranges described above.

One or more of the kitchen roll towels 2 thus obtained are arranged with their longitudinal lengths aligned and their widths aligned, and then wrapped in a caramel wrapper using a wrapping film 20 according to a known method, as shown in Figure 1.

The present invention has been described above using embodiments, but it goes without saying that the technical scope of the present invention is not limited to the scope described in the above embodiments and examples. It will be clear to those skilled in the art that various modifications and improvements can be made to the above embodiments. Furthermore, it is clear from the claims that forms incorporating such modifications or improvements can also be included within the technical scope of the present invention.

The following examples and comparative examples will explain this embodiment in more detail.

(Examples 1 to 17 and Comparative Examples 1 to 8)
NBKP and LBKP were used as raw material pulp in the proportions (mass%) shown in Tables 1 to 3, and kitchen roll towel products of Examples 1 to 25 and Comparative Examples 1 to 12 were produced through the following processes: (1) papermaking and creping, (2) embossing, (3) roll winding, and (4) caramel wrapping. Parameters were measured for the kitchen towel roll products of all of the above Examples and Comparative Examples, and sensory evaluations were also conducted. The results are shown in Tables 1 to 3. The kitchen towels of Examples 1 to 25 and Comparative Examples 1 to 8 had uneven patterns derived from the papermaking machine.

The sensory evaluation was carried out by 20 monitors who selected "good" or "bad" for each evaluation item. The evaluation criteria were as follows: ◎, ○, and △ were considered to be acceptable.
◎: When there are 18 to 20 people who chose "Good" ○: When there are 14 to 17 people who chose "Good" △: When there are 10 to 13 people who chose "Good" ×: When there are 6 to 9 people who chose "Good" ××: When there are no people who chose "Good" or when there are 1 to 5 people who chose "Good"

Each evaluation item will be explained below.
<Water absorption per sheet>
The monitors used one sheet and evaluated how much water remained on the surface.
<Can you use the sheet without waste?>
The monitors used one sheet and evaluated whether they felt it was a waste to discard it.
<Cosmetic>
The occurrence of scorch and unbonded areas was visually evaluated.
<Resistant to tearing of packaging film>
The resistance of the packaging film to tearing when the product was displayed or carried by hand was evaluated.
<Openability>
The ease of opening the packaging film by tearing it with fingers or by making a hole in it was evaluated.
<Wipeability>
The ease of wiping was evaluated by the monitors when they used the product.
<Tactile sensation when in use>
The monitors evaluated the quality of the feel when using the product.
The results are shown in Tables 1 to 3.

Tables 1 to 3 show that by combining and satisfying the various components of this embodiment, a kitchen roll towel product can be obtained that receives a passing rating of ⊚ in most of the evaluation categories of "absorbency per sheet," "whether the sheet can be used without waste," "decorative appearance," "resistance to tearing of the film," "ease of opening," "ease of wiping," and "tactile feel during use," although some receive a passing rating of △.

1. Kitchen roll towel products (products)
2. Kitchen roll towels (roll)
10 Core 11x Kitchen towel 11a Front surface of kitchen towel 11b Back surface of kitchen towel 20 Packaging film

Claims (8)

A kitchen roll towel product,
a kitchen roll towel obtained by winding up a sheet-shaped kitchen towel that is a two-ply laminate having an embossed pattern into a roll;
a packaging film for packaging the kitchen roll towel;
The kitchen towel is
The paper has a paper machine-derived uneven pattern provided between the head box of the paper machine and the inlet of the Yankee dryer,
The basis weight is 30 g/m ² or more and 54 g/m ² or less, the water absorption is 200 g/m ² or more and 600 g/m ² or less, and the specific volume is 8 cm ³ /g or more and 20 cm ³ /g or less,
The roll density of the kitchen roll towel is 0.04 g/cm ^or more and 0.15 g/cm or ^less ,
the kitchen towel further has an embossed pattern different from the uneven pattern derived from the paper machine, and an embossing roll for applying the embossed pattern has an area ratio of convex portions of 4% to 40%;
the embossed pattern is a linear embossed pattern,
the linear embossed pattern has a thickness of 0.1 mm or more and 4 mm or less, a length of 5 mm or more, and a total length including the lengths of the embosses of 50 cm/100 cm2 ^or more and 550 cm/100 cm2 ^or less;
The kitchen roll towel product has a root mean square height of surface roughness of the kitchen towel in a portion where the embossed pattern is not provided of 35 μm or more . The kitchen roll towel product according to claim 1, wherein one or more of the kitchen roll towels are wrapped in caramel by the packaging film. The kitchen roll towel product according to claim 1 or 2, wherein the DMDT/DCDT ratio of the kitchen towel is 0.8 or more and 2.0 or less, and the DMDT is 4 N/25 mm or more and 16 N/25 mm or less, and the DCDT is 3 N/25 mm or more and 13 N/25 mm or less. 4. The kitchen roll towel product according to claim 1, wherein the kitchen towel further has a plurality of perforations extending in the width direction thereof to cut the kitchen towel in the width direction, the plurality of perforations being arranged at predetermined intervals in the longitudinal direction, and the area of the kitchen towel piece surrounded by two adjacent perforations in the longitudinal direction is 0.02 ^m2 or more and 0.10 ^m2 or less. The kitchen roll towel product according to any one of claims 1 to 4, wherein the kitchen towel has a ply peel strength of 0.01 N/75 mm or more and 1.5 N/75 mm or less. The kitchen roll towel product according to any one of claims 1 to 5, wherein the roll diameter of the kitchen roll towel is 113 mm or more and 200 mm or less. The kitchen roll towel product according to any one of claims 1 to 6 , wherein the packaging film has heat-sealability. The kitchen roll towel product according to any one of claims 1 to 7 , wherein the thickness of the packaging film is 15 µm or more and 40 µm or less.