JP7743181B2 - Paper wiper - Google Patents

Description

The present invention relates to a paper wiper.

Paper wipers made from raw materials such as pulp and recycled paper are used as industrial wipers in, for example, medical settings, corporate and university laboratories, various manufacturing plants, food manufacturing plants, and food processing plants. These paper wipers typically have between two and six plies, and are available in a variety of product forms.

For example, Patent Document 1 discloses industrial paper wipes that are made by adding 0.125 to 1.25 parts by mass of a wet strength agent and 0.01 to 0.5 parts by mass of a softener per 100 parts by mass of constituent fibers, and then calendering the paper.

JP 2010-209482 A

However, the paper wipers mentioned above are required to be absorbent, have a pleasant feel when used (e.g., feel of the wiper and wiping comfort), durable, and produce little dust (e.g., little paper dust falling off the wiper), but the reality is that conventional paper wipers do not meet all of these requirements. Therefore, there is a need to develop a paper wiper that can meet all of these requirements to a high degree.

The present invention was developed in consideration of these circumstances, and aims to provide paper wipers that are highly absorbent, comfortable to use, durable, and generate little dust.

As a result of intensive research into achieving the above-mentioned object, the inventors have discovered that a three-ply paper wiper is made of three layers of base paper, the paper wiper is embossed, the three plies of the paper wiper have a total basis weight of 56.0 g/ ^m2 or more and 80.0 g/ ^m2 or less, the three plies of the paper wiper have a total paper thickness of 0.40 mm or more and 0.62 mm or less, the three plies of the paper wiper have a total longitudinal strength in a dry state of 31.4 N/25 mm or more and 54.9 N/25 mm or less, and the three plies of the paper wiper have a total lateral strength in a dry state of 7.8 N/25 mm or more and 19.6 N/25 mm or less, and have completed the present invention based on this discovery.

In other words, the present invention is as follows:

(1)
The paper wiper is a three-ply paper wiper made of three layers of base paper, and an embossment is formed on the paper wiper. The three plies of the paper wiper have a total basis weight of 56.0 g/ ^m2 or more and 80.0 g/ ^m2 or less. The three plies of the paper wiper have a total paper thickness of 0.40 mm or more and 0.62 mm or less. The three plies of the paper wiper have a total longitudinal strength in a dry state of 31.4 N/25 mm or more and 54.9 N/25 mm or less. The three plies of the paper wiper have a total transverse strength in a dry state of 7.8 N/25 mm or more and 19.6 N/25 mm or less.
(2)
The paper wiper according to (1), wherein the embossment is a pin embossment.
(3)
The paper wiper according to (1) or (2), wherein the embossing depth of the embossing is 300 μm or more and 850 μm or less.
(4)
The paper wiper according to any one of (1) to (3), wherein the embossing area ratio of the embossing is 0.42% or more and 1.40% or less.
(5)
The paper wiper according to any one of (1) to (4), wherein the pitch between adjacent embossments is 1.0 mm or more and 3.8 mm or less.
(6)
The paper wiper according to any one of (1) to (5), wherein the basis weight per sheet of the base paper before plying is 18.7 g/m ² or more and 26.7 g/m ² or less.
(7)
The paper wiper according to any one of (1) to (6), wherein the thickness of each base paper sheet before plying is 0.78 mm/10 plies or more and 1.25 mm/10 plies or less.
(8)
The paper wiper is the paper wiper according to any one of (1) to (7), in which three sheets of the base paper are stacked and folded in four.

The present invention makes it possible to provide paper wipers that are highly absorbent, comfortable to use, durable, and generate little dust.

FIG. 1 is a schematic cross-sectional view of a paper wiper according to this embodiment. FIG. 2 is a schematic top view of the paper wiper according to this embodiment.

The following describes in detail the form for carrying out the present invention (hereinafter simply referred to as the "present embodiment"). The following present embodiment is an example for explaining the present invention, and is not intended to limit the present invention to the following content. The present invention can be carried out with appropriate modifications within the scope of its gist.

In the drawings, identical elements will be given the same reference numerals, and duplicate explanations will be omitted. Furthermore, unless otherwise specified, positional relationships such as up, down, left, and right will be based on the positional relationships shown in the drawings. Furthermore, the dimensional ratios of the drawings are not limited to those shown.

Furthermore, in this specification, terms preceded by "abbreviation" indicate the meaning of the term excluding "abbreviation" within the scope of common technical knowledge of a person skilled in the art, and are intended to include the meaning itself excluding "abbreviation."

(Paper wiper)

Figure 1 is a schematic cross-sectional view of the paper wiper according to this embodiment, and Figure 2 is a schematic top view of the paper wiper according to this embodiment.

The paper wiper 1 of this embodiment is a three-ply paper wiper 1 made by stacking three sheets of base paper 11, 12, and 13, and an embossment 20 is formed on the paper wiper 1. The total basis weight of the three plies of the paper wiper 1 is 56.0 g/ ^m2 or more and 80.0 g/ ^m2 or less. The total paper thickness of the three plies of the paper wiper 1 is 0.40 mm or more and 0.62 mm or less. The total longitudinal strength of the three plies of the paper wiper 1 in a dry state is 31.4 N/25 mm or more and 54.9 N/25 mm or less. The total lateral strength of the three plies of the paper wiper 1 in a dry state is 7.8 N/25 mm or more and 19.6 N/25 mm or less.

In this embodiment, the base papers 11, 12, and 13 are embossed into three plies to create a paper wiper 1 with specific basis weight, thickness, longitudinal strength, and lateral strength, which satisfies all requirements at a high level, including absorbency, usability such as feel and wiping comfort, durability, and low dust generation. Note that "dust generation" here refers to paper dust (shedded paper dust) that falls off the paper wiper 1 during use or manufacturing, and includes, for example, fiber fragments and filler powder from the paper wiper 1.

When the base papers 11, 12, and 13 are made using a papermaking machine capable of forming dryer surfaces and felt surfaces, it is preferable that the top and bottom surfaces of the three plies of base papers 11, 12, and 13 be arranged so that they are both dryer surfaces. In the case of Figure 1, it is preferable that the surface side of the top base paper 11 be the dryer surface, and the back surface of the bottom base paper 13 be the dryer surface. This arrangement improves the feel of both the surface (e.g., the surface of base paper 11) and the back surface (e.g., the back surface of base paper 13) of the paper wiper 1, and also makes wiping more comfortable. The arrangement of the intermediate base paper 12 sandwiched between the top base paper 11 and the bottom base paper 13 need not be particularly limited.

The total basis weight of the three plies of the paper wiper 1 (the total of the three ply-up base papers 11, 12, and 13) is 56.0 g/ ^m2 or more and 80.0 g/ ^m2 or less. This basis weight is preferably 60.0 g/ ^m2 or more and 76.0 g/ ^m2 or less. This basis weight is the product basis weight of the paper wiper 1.

The total paper thickness of the three plies of paper wiper 1 is 0.40 mm or more and 0.62 mm or less. This paper thickness is preferably 0.45 mm or more and 0.57 mm or less. This paper thickness is the product paper thickness of paper wiper 1. By keeping the product basis weight and product paper thickness of paper wiper 1 within the above ranges, the paper wiper will have good usability, such as water absorbency, feel, and wiping comfort, and will produce little dust.

The total longitudinal strength of the three plies of paper wiper 1 in a dry state is 31.4 N/25 mm or more and 54.9 N/25 mm or less. This longitudinal strength is preferably 35.2 N/25 mm or more and 51.0 N/25 mm or less.

Note that the longitudinal strength referred to here refers to the tensile strength in the longitudinal width direction of the three plies of the paper wiper 1 when dry. The longitudinal strength can be measured in accordance with JIS P 8113. The longitudinal width direction refers to the machine direction (MD) in which the paper wiper 1 is manufactured.

The combined lateral strength of the three plies of paper wiper 1 in a dry state is 7.8 N/25 mm or more and 19.6 N/25 mm or less. This lateral strength is preferably 9.8 N/25 mm or more and 15.7 N/25 mm or less. By keeping the longitudinal and lateral strength of paper wiper 1 within the above ranges, the paper wiper will have a good feel in use, including a good wiping sensation, and will be durable.

The term "cross strength" here refers to the tensile strength in the cross direction of the three plies of the paper wiper 1 when dry. Cross strength can be measured in accordance with JIS P 8113. The cross direction refers to the direction perpendicular to the flow direction during the manufacture of the paper wiper 1 (CD; Cross Direction).

The paper wiper 1 has an embossment 20 formed on the base material 10, which is made up of three stacked sheets of base paper 11, 12, and 13. As shown in Figure 1, this embossment 20 is formed on the three sheets of base paper 11, 12, and 13. By forming an embossment on the paper wiper 1, the paper thickness and strength of the paper wiper 1 can be adjusted to an appropriate range, resulting in a paper wiper that has good usability in terms of absorbency, feel, and wiping comfort, as well as being durable and generating little dust.

The shape of the embossing is not particularly limited, and examples include pin embossing, dot embossing, and decorative embossing. Pin embossing refers to a concave shape that integrates three base papers 11, 12, and 13 through embossings 21, 22, and 23 formed on each of the base papers. The pin embossing is a pin-shaped (approximately conical, pierced with a sharp needle) shape. Dot embossing refers to a concave shape that integrates three base papers 11, 12, and 13 through embossings 21, 22, and 23 formed on each of the base papers. The shape is not particularly limited, and examples include rectangular parallelepiped, cylindrical, triangular prism, and other embossings (flat-pressed types). Decorative embossing refers to an embossing in which the pressed shape is some kind of pattern (flower, company logo, character, etc.). Among these, pin embossing is preferred because it results in a thicker paper and greater water absorption when the three base papers are embossed and integrated.

The embossing depth D is preferably 300 μm or more and 850 μm or less, and more preferably 420 μm or more and 700 μm or less. Setting the embossing depth D within this range results in a paper wiper that is durable and has good absorbency, feel, wiping comfort, and other aspects of use. The embossing depth D here refers to the depth from the bottom of the outer surface of the embossment 23 of the bottommost (lowest) base paper 13 to the outer surface of the topmost (highest) base paper 11 when three base papers 11, 12, and 13 are stacked together (see Figure 1). The embossing depth D can be measured in accordance with the method described in the Examples below.

In this embodiment, the surface of the paper wiper 1 may have areas with a shallow embossing depth D and areas with a deep embossing depth D. Alternatively, the embossing may be formed with a gradient so that the embossing depth D gradually becomes shallower (or deeper). In the case of a paper wiper 1 having such different embossing depths D, it is sufficient that the paper wiper 1 has at least embossings that satisfy the above-mentioned conditions. Furthermore, according to this embodiment, it is preferable that 50% or more of the embossings on the paper wiper 1 satisfy the above-mentioned conditions, more preferably that 70% or more of the embossings satisfy the above-mentioned conditions, even more preferably that 90% or more of the embossings satisfy the above-mentioned conditions, and even more preferably that 100% of the embossings (all embossings) satisfy the above-mentioned conditions.

The embossed area ratio of the embossments 20 is preferably 0.42% or more and 1.40% or less, and more preferably 0.57% or more and 1.05% or less. By setting the embossed area ratio within this range, the paper wiper can be made durable and have good usability, such as good absorbency, feel, and wiping comfort. The embossed area ratio refers to the percentage of the total area of the embossments 20 per unit area when viewed from the top of the paper wiper 1 (see Figure 2) (total number of embossed areas per unit area; %). Specifically, it is the area ratio of 30 embossments measured in accordance with the method described in the Examples below.

In this embodiment, the surface of the paper wiper 1 may have areas with a low embossed area ratio (sparse embossing) and areas with a high embossed area ratio (dense embossing). Alternatively, the embossing may be sloped so that the embossed area ratio gradually decreases (or increases). In the case of a paper wiper 1 having areas with different embossed area ratios, it is sufficient that the embossed area ratios of 30 adjacent embossments within the embossed area of the paper wiper 1 (the entire embossed area) satisfy the above-mentioned conditions. Furthermore, according to this embodiment, it is preferable that 50% or more of the embossed area of the paper wiper 1 satisfy the above-mentioned conditions, more preferably 70% or more of the area satisfies the above-mentioned conditions, even more preferably 90% or more of the area satisfies the above-mentioned conditions, and even more preferably 100% of the area (the entire embossed area) satisfies the above-mentioned conditions.

The pitch distance P between adjacent embossments 201, 202 in the embossments 20 is preferably 1.0 mm or more and 3.8 mm or less, and more preferably 1.5 mm or more and 3.2 mm or less. By setting the pitch distance P within this range, the paper wiper can be made durable and have good absorbency, feel, and wiping comfort. The pitch distance P here refers to the linear distance between the centers of gravity O1, O2 of adjacent embossments 201, 202, respectively, and is the minimum value of the pitch distance P between embossments 20 arranged on the substrate 10. The pitch distance P can be measured in accordance with the method described in the Examples below.

In this embodiment, the surface of the paper wiper 1 may have areas with a small pitch interval P (where the embossing is densely arranged) and areas with a large pitch interval P (where the embossing is densely arranged). Alternatively, the embossing may be formed with an inclination so that the pitch interval P gradually decreases (or increases). In the case of a paper wiper 1 having areas with different pitch intervals P, it is sufficient that the smallest pitch interval P (minimum value of pitch interval P) in the embossed area of the paper wiper 1 (the entire embossed area) satisfies the above-mentioned condition. Furthermore, according to this embodiment, it is preferable that 50% or more of the embossed area of the paper wiper 1 satisfies the above-mentioned pitch interval P condition, more preferably 70% or more of the area satisfies the above-mentioned pitch interval P condition, even more preferably 90% or more of the area satisfies the above-mentioned pitch interval P condition, and even more preferably 100% of the area (the entire embossed area) satisfies the above-mentioned pitch interval P condition.

(base paper)

Next, we will explain the base papers 11, 12, and 13 before they are plyed up.

The basis weight per sheet of the base papers 11, 12, and 13 before plying up is preferably 18.7 g/m ² or more and 26.7 g/m ² or less, and more preferably 20.0 g/m ² or more and 25.3 g/m ² or less. By setting the basis weight within this range, when the three base papers are stacked to produce the paper wiper 1, the paper wiper has good water absorbency, good feel in use, such as feel to the touch and wiping comfort, and generates little dust.

The thickness of each sheet of base paper 11, 12, 13 before plying is preferably 0.78 mm/10 plies or more and 1.25 mm/10 plies or less, and more preferably 0.89 mm/10 plies or more and 1.13 mm/10 plies or less. By keeping the thickness within this range, when three sheets of base paper are stacked to make paper wiper 1, it is possible to produce a paper wiper that has good water absorbency, feel, wiping comfort, and other usability characteristics, and generates little dust. Note that the paper thickness referred to here refers to the thickness when ten sheets of base paper 11, 12, 13 are stacked together, and is equivalent to the thickness of ten sheets of base paper 11, 12, 13 stacked together (10 plies).

The base papers 11, 12, and 13 that make up the paper wiper 1 can be made from materials such as wood pulp (such as bleached softwood kraft pulp (NBKP) and bleached hardwood kraft pulp (LBKP)), non-wood pulp (such as hemp pulp and bamboo pulp), and chemical fibers (such as cellulose-based fibers, olefin-based chemical fibers, and polyester-based fibers). Among these, wood pulp, which has particularly excellent water absorption properties, is preferred.

The wood species of hardwood bleached kraft pulp (LBKP) is preferably pulp made from hardwoods such as eucalyptus, poplar, acacia, and oak. The wood species of softwood bleached kraft pulp (NBKP) is preferably pulp made from softwoods such as fir, pine, cedar, and cypress.

The base papers 11, 12, and 13 preferably have a wood pulp content of 70% by mass or more, and more preferably 90% by mass or more.

If base papers 11, 12, and 13 contain NBKP, the content is preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more.

If base papers 11, 12, and 13 contain LBKP, the content is preferably 30% by mass or less, more preferably 20% by mass or less, and even more preferably 10% by mass or less.

Furthermore, base papers 11, 12, and 13 may contain recycled paper pulp derived from milk cartons, but the recycled paper pulp content is preferably 20% by mass or less, more preferably 10% by mass or less, even more preferably 5% by mass or less, and even more preferably none. By controlling the recycled paper pulp content within this range, the balance of absorbency, strength, low dust generation, etc. of paper wiper 1 is further improved.

In this embodiment, recycled paper pulp refers to recycled paper pulp derived from milk cartons. Recycled paper pulp derived from milk cartons is primarily softwood pulp, which makes it easy to ensure the strength of the paper wiper 1. However, there is a large variation in quality, and if the content is too high, it tends to affect the quality of the product. Therefore, it is preferable to keep the content within the above range. Therefore, for example, the above-mentioned NBKP and LBKP do not fall under the category of recycled paper pulp.

The color tone of the paper wiper 1 is not particularly limited, and may be white, obtained by using bleached pulp or the like for the base paper 11, 12, 13, or brown, obtained by using unbleached pulp or the like for the base paper 11, 12, 13.

The paper wiper 1 may also contain other additives, provided that they do not impair the effects of this embodiment. Examples of such additives include softeners, wet strength agents, and dry strength agents. However, the total additive content is preferably 2.0% by mass or less, more preferably 1.0% by mass or less, and even more preferably 0.5% by mass or less.

Base papers 11, 12, and 13 can be manufactured using a papermaking process using a papermaking machine. It is preferable to use a papermaking machine capable of forming a dryer surface and a felt surface in the papermaking process. For example, it is preferable to perform a pressing process in which water is removed using a press roll and a felt, and a drying process in which drying is performed using a Yankee dryer, and it is preferable to use a papermaking machine equipped with such devices. This allows the base papers 11, 12, and 13 to be formed with a dryer surface and a felt surface, improving the feel and providing a more comfortable wipe.

In the papermaking process, for example, the basis weight of the base papers 11, 12, and 13 can be increased by, for example, increasing the amount of pulp used. The thickness of the base papers 11, 12, and 13 can be increased by, for example, increasing the amount of pulp used. Furthermore, the longitudinal strength and transverse strength can be increased by, for example, increasing the amount of pulp used, strengthening beating using DDR or the like, or adding wet strength agents or dry strength agents, etc.

(Product format, etc.)

The paper wiper 1 described above may be made by plying together base papers 11, 12, and 13 to form the embossment 20, but if necessary, the plyed-up base papers 11, 12, and 13 may be folded into multiple sheets (e.g., folded into thirds, fourths, etc.). One suitable example of such a paper wiper 1 is made by stacking three sheets of base paper 11, 12, and 13 and folding them into fourths.

For example, a quartering method can be used in which the approximately rectangular paper wiper 1 is folded in half and then folded again vertically in half, resulting in a folding pattern known as a cross fold, a right-angle quarter fold, or a crisscross fold. Other folding methods include an outward quarter fold (e.g., a W fold), a rolled quarter fold, a semi-rolled quarter fold, and a gate fold. In this way, the appropriate folding method can be selected depending on the product's intended use, etc.

The dimensions and shape of the paper wiper 1 as a product are not particularly limited, and it can be made into a shape that is appropriate for the product, taking into consideration the manner of use and purpose of use. For example, it may be rectangular (rectangular, square), circular, oval, polygonal, etc., but a rectangular shape is preferable when used in a pop-up storage box for paper wipers.

For example, if the paper wiper 1 according to this embodiment is rectangular, the vertical width of the paper wiper 1 is preferably 320 mm or more and 350 mm or less, and more preferably 325 mm or more and 345 mm or less. The horizontal width of the paper wiper 1 is preferably 370 mm or more and 395 mm or less, and more preferably 375 mm or more and 390 mm or less. Furthermore, it is preferable that both the vertical width and the horizontal width are within the above-mentioned ranges.

As explained above, the paper wiper 1 according to this embodiment is highly absorbent, comfortable to use, durable, and generates little dust. Therefore, the paper wiper 1 according to this embodiment can be suitably used in research laboratories and other laboratories, manufacturing plants for electronic components, cosmetics, pharmaceuticals, food, and various other materials and products, and medical facilities such as hospitals and nursing homes.

The present invention will be explained in more detail with reference to the following examples and comparative examples, but the present invention is not limited to these examples in any way.

<Example 1>

(Making Paper Wiper 1)

First, base papers 11, 12, and 13 were produced using a papermaking machine capable of forming a dryer surface and a felt surface on the base paper by using softwood bleached kraft pulp (NBKP) as the material and performing a pressing process in which the paper was dewatered using a press roll and a felt, and a drying process in which the paper was dried using a Yankee dryer. These base papers 11, 12, and 13 were then stacked in three plies to form a laminate. The three plies of base papers 11, 12, and 13 were arranged so that both the top surface (the surface of the top base paper 11 in Figure 1) and the bottom surface (the back surface of the bottom base paper 13 in Figure 1) of the laminate were the dryer surfaces. Specifically, in Figure 1, the top base paper 11 (i.e., the outermost surface of the laminate) was the dryer surface and the bottom was the felt surface, the middle base paper 12 was the felt surface and the bottom was the dryer surface, and the bottom base paper 13 was the felt surface and the bottom (i.e., the back surface of the laminate) was the dryer surface. This laminate was then embossed using pin embossing or dot embossing, and folded into four to produce the paper wiper 1 having the structure shown in Figures 1 and 2.

(Measurement of physical properties)

The product basis weight is the basis weight of the three plies of paper wiper 1 (the sum of the three ply-up base papers 11, 12, and 13), and was measured in accordance with JIS P 8124.

The product paper thickness is the total thickness of the three plies of paper wiper 1 (the total of the three ply-up base papers 11, 12, and 13), and was measured under JIS P 8111 conditions (23±1°C, 50±2% relative humidity) using a thickness gauge (Ozaki Seisakusho's upright dial thickness gauge "PEACOCK R1-B type"), applying a pressure of 3.7 kPa to the measuring probe.

The longitudinal strength of the three plies of paper wiper 1 in a dry state (longitudinal strength of product strength) is the tensile strength in the longitudinal width direction of paper wiper 1 (the three plies of base paper 11, 12, and 13) when dry, measured in accordance with JIS P 8113. The longitudinal width direction here refers to the machine direction (MD) along which paper wiper 1 is manufactured, and refers to the strength in the short direction (longitudinal width direction) of paper wiper 1.

The total lateral strength of the three plies of paper wiper 1 in a dry state (lateral strength of product strength) is the tensile strength in the width direction of paper wiper 1 (the three plies of base paper 11, 12, and 13) when dry, and was measured in accordance with JIS P 8113. The width direction here refers to the direction perpendicular to the flow direction during the manufacture of paper wiper 1 (CD; Cross Direction), and refers to the strength in the longitudinal direction (width direction) of paper wiper 1.

Regarding the embossing shape, "pin embossing" is conical, and "dot embossing" is cylindrical.

The pitch interval of the embossed shape was measured by capturing an image of the surface of the paper wiper 1 (the object of measurement) viewed from above (see Figure 2) using a microscope (Keyence Corporation, Digital Microscope "VHX-6000") at 20x magnification, and measuring the linear distance between the centers of gravity O1 and O2 of adjacent embossments 201 and 202 in the captured image. In this way, the pitch interval was measured at 30 points, and the arithmetic average of these measurements was taken as the pitch interval.

The embossed area ratio of the embossed shape was measured by photographing the surface of the paper wiper 1, which was the object of measurement, viewed from above (see FIG. 2), using a microscope (Keyence Corporation, digital microscope "VHX-6000") at a magnification of 20x, and determining the area, as viewed from above, of the embossments 21 formed on the outermost base paper 11 of the three base papers 11, 12, and 13. The total value of 30 points thus determined was converted into a ratio per unit area (area ratio %).
Specifically, 30 adjacent embossments 21 were selected from the captured image, and the smallest circumscribing rectangle (rectangle or square) encompassing all 30 embossments was defined as the unit area. The emboss area ratio was then calculated using the following formula:

Embossed area ratio (%) = total area of 30 adjacent embossed points / area of smallest circumscribed rectangle including all 30 embossed points × 100

The embossing depth of the embossed shape was measured by capturing a cross-sectional image of the surface of the paper wiper 1 (see Figure 1) at 12x magnification using a one-shot 3D shape measuring device (Keyence Corporation, digital microscope "VR-3000"), and measuring the depth D from the bottom of the outer surface of the embossment 23 of the bottommost (lowest) base paper 13 to the outer surface of the topmost (highest) base paper 11 in the resulting image, where three base papers 11, 12, and 13 were stacked. In this way, the embossing depth D was measured at 30 points, and the arithmetic average of these measurements was taken as the embossing depth.

The basis weight of each sheet of base paper 11, 12, and 13 was measured in accordance with JIS P 8124.

The thickness of a single sheet of base paper 11, 12, and 13 was measured under the conditions of JIS P 8111 (23±1°C, 50±2% relative humidity) using a thickness gauge (Ozaki Seisakusho's upright dial thickness gauge "PEACOCK R1-B type"), applying a pressure of 3.7 kPa to the measuring probe.

Unless otherwise specified, measurements and evaluations in this example were carried out after maintaining the sample in equilibrium under the temperature and humidity conditions specified in JIS P 8111 (23±1°C, 50±2% RH).

<Examples 2-8, Comparative Examples 1-5>

Paper wipers were produced in the same manner as in Example 1, except for the changes made to the conditions listed in Tables 1 and 2.

<Evaluation>

(Total Water Absorption (TWA)
The water absorption (TWA) was measured by first cutting the obtained paper wiper 1 into a square test piece of 76 x 76 mm, and measuring the dry mass (W1). After that, the test piece was immersed in distilled water for 2 minutes, and then the test piece was hung in a stretched state (RH 100%) with one corner of the test piece being the upper apex, and this apex and the two adjacent corners were supported, and the mass (W2) after leaving for 30 minutes was measured. Then, the value of (W2 - W1) was calculated, and this value was converted to the water retention capacity (g/ ^m2 ) per 1 ^m2 of sample, which was used as the water absorption rate.

The following items were subjected to a sensory evaluation conducted by 60 people. For each item, 60 people rated them on a scale of 1 to 5 based on the following criteria, and the average score was calculated. The average score was then used to evaluate the product based on the following criteria.

(Evaluation of wiping comfort)
A sample prepared under the above conditions was used to wipe an object (a plastic desk on which 50 mL of water had been spilled) at 23±1°C and 50±2% RH, and the wiping feel was evaluated on a 5-point scale from 1 to 5.

・4 points, 5 points: The wiping feeling was particularly good, and the object could be wiped smoothly.
3 points: The wiping was comfortable and the object could be wiped smoothly.
・1 point, 2 points: The object was difficult to wipe.

Overall rating: ◎: Average score of 60 people is 4.0 points or more. ○: Average score of 60 people is 3.0 points or more but less than 4.0 points. ×: Average score of 60 people is less than 3.0 points.

(Durability evaluation)
The samples prepared under the above conditions were used to wipe an object (a plastic desk on which 50 mL of water had been spilled) at 23±1°C and 50±2% RH, and the durability of the samples was evaluated on a 5-point scale from 1 to 5.

・4 points, 5 points: When wiping the object, it felt particularly difficult to tear.
・3 points: It felt like it was difficult to tear when wiping the object.
・1 point, 2 points: When wiping the object, it tore or felt like it was easily torn.

Overall rating: ◎: Average score of 60 people is 4.0 points or more. ○: Average score of 60 people is 3.0 points or more but less than 4.0 points. ×: Average score of 60 people is less than 3.0 points.

(Evaluation of low dust generation)
A sample prepared under the above conditions was used to wipe an object (a plastic desk on which 50 mL of water had been spilled) at 23±1°C and 50±2% RH, and the presence or absence of dust generation was evaluated on a 5-point scale from 1 to 5.

4 points, 5 points: When wiping the object, there was particularly little fuzzing.
3 points: When wiping the object, there was little fuzz.
・1 point, 2 points: When wiping the object, there was a lot of fluffing, and dust such as paper powder was observed on the object.

Overall rating: ◎: Average score of 60 people is 4.0 points or more. ○: Average score of 60 people is 3.0 points or more but less than 4.0 points. ×: Average score of 60 people is less than 3.0 points.

The conditions and evaluation results for each example and comparative example are shown in Tables 1 and 2. Note that "pin" in the tables refers to pin embossing, and "dot-shaped" refers to dot-shaped embossing (cylindrical shape).

From the above, it has been confirmed that the paper wiper 1 of this embodiment is at least highly absorbent, comfortable to use, durable, and generates little dust.

1: Paper wiper,
10: Base material,
11, 12, 13: Original paper,
20, 21, 22, 23, 201, 202: embossed,
D: embossing depth,
P: pitch interval,
O1, O2: Center of gravity

Claims (3)

It is a three-ply paper wiper made of three layers of base paper.
The paper wiper has an embossment formed thereon,
The total basis weight of the three plies of the paper wiper is 60.0 g/m ² or more and 76.0 g/m ² or less,
The total thickness of the three plies of the paper wiper is 0.40 mm or more and 0.62 mm or less,
The total longitudinal strength of the three plies of the paper wiper in a dry state is 31.4 N/25 mm or more and 54.9 N/25 mm or less,
The total lateral strength of the three plies of the paper wiper in a dry state is 7.8 N/25 mm or more and 19.6 N/25 mm or less,
The embossment is a pin embossment having a conical shape,
The embossing depth of the embossing is 300 μm or more and 850 μm or less,
The thickness of each base paper sheet before plying is 0.78 mm/10 plies or more and 1.25 mm/10 plies or less ,
The embossing area ratio of the embossing is 0.42% or more and 1.40% or less,
The basis weight per sheet of the base paper before plying is 20.0 g/m ² or more and 25.3 g/m ² or less .
Paper wiper. The pitch between adjacent embossments is 1.0 mm or more and 3.8 mm or less.
The paper wiper of claim 1 . The paper wiper is made by stacking three sheets of the base paper and folding them into four.
The paper wiper according to claim 1 or 2 .