CN116724156A

CN116724156A - Wet sheet for cleaning

Info

Publication number: CN116724156A
Application number: CN202280008919.8A
Authority: CN
Inventors: 山崎侑平
Original assignee: Daio Paper Corp
Current assignee: Daio Paper Corp
Priority date: 2021-01-28
Filing date: 2022-01-12
Publication date: 2023-09-08
Also published as: JP2022115660A; KR20230132763A; WO2022163344A1; US20240057840A1

Abstract

A cleaning wet sheet (100) is provided in which a 1 st embossed block (30) comprising a plurality of embossed patterns (21) is arranged in series from a 1 st side (a) to a 2 nd side (b), a plurality of embossed block rows (31) are arranged in series from a 3 rd side (c) to a 4 th side (d), and the embossed patterns (21) are arranged so that at least one of the embossed patterns is present on a line extending perpendicularly from the 3 rd side (c) to the 4 th side (d). Thus, the embossments (21) have overlapping edges (Overlapping margin) with each other. In addition, between each embossing block (30) 25% -50% of non-embossing portions (40) are arranged. Therefore, the release property of the chemical liquid is improved, and the occurrence of wiping streaks can be reduced. In addition, the wiping performance of dirt can be improved, and the increase in wiping resistance can be suppressed.

Description

Wet sheet for cleaning

Technical Field

The present invention relates to a cleaning wet sheet.

Background

Conventionally, it is known that the cleaning surface of a cleaning wet sheet is embossed with protrusions to improve the wiping property, handling property, visibility of sheet dirt, and the like of the dirt (for example, refer to patent document 1).

Prior art literature

Patent literature

Patent document 1: japanese patent laid-open publication No. 2018-064723

Disclosure of Invention

However, in the cleaning wet sheet shown in patent document 1, since the orientations (for example, the orientations in the longitudinal direction) on the paper surface of the convex portions are aligned and arranged in series, there is a case where a portion (so-called "wiping streak") where wiping by the convex portions is not performed is generated on the surface to be cleaned. A user who visually recognizes the wiping streak may judge that the liquid medicine is exhausted and dried to discard the sheet, although the liquid medicine remains in the sheet, and sometimes unnecessarily use many sheets.

The invention aims to provide a cleaning wet sheet which can reduce the generation of wiping stripes when a cleaning tool with a head is installed for wiping.

The invention described in the first aspect of the present invention is a cleaning wet sheet comprising a base paper sheet impregnated with a chemical solution, and being used by being attached to a cleaning tool having a head,

the cleaning wet sheet includes an embossed block formed by integrating a plurality of embossed patterns protruding from the 1 st surface of the cleaning wet sheet,

a plurality of embossing blocks are arranged continuously from the 1 st side to the 2 nd side opposite to the 1 st side to form an embossing block row,

a non-embossed portion where the embossing is not arranged is provided between the embossing block and the other adjacent embossing block,

the embossing block row is arranged in plural from the 3 rd side orthogonal to the 1 st side to the 4 th side opposite to the 3 rd side,

the non-embossed portion is provided so as to be 25% to 50% of the area of the cleaning wet sheet,

the embossments are arranged such that at least one of the embossments is present on a straight line extending perpendicularly from any point on the 3 rd side to the 4 th side.

The invention described in the second aspect of the present invention is the cleaning wet sheet described in the first aspect of the present invention,

comprises concave embossing, wherein the concave embossing is embossing protruding from the 2 nd surface of the cleaning wet sheet,

the embossing block is composed of a combination of a plurality of the convex embossments and the concave embossments,

the concave embossing is arranged in such a manner that at least one line extending from any point on the 3 rd side to the 4 th side exists.

The third aspect of the present invention provides the cleaning wet sheet according to the first or second aspect of the present invention,

the raw paper sheet includes a hydrophobic fiber layer forming a surface of the sheet, and a hydrophilic fiber layer sandwiched between the hydrophobic fiber layers,

the fibers of the hydrophobic fiber layer and the hydrophilic fiber layer are interwoven in a boundary region therebetween.

The invention described in the fourth aspect of the present invention is the cleaning wet sheet described in any one of the first to third aspects of the present invention,

the angle between the long axis direction of the embossing and the 1 st direction is 30 DEG to 60 DEG, the 1 st direction is orthogonal to the 1 st side,

the embossing block is diamond-shaped.

The invention according to a fifth aspect of the present invention is the cleaning wet sheet according to any one of the first to fourth aspects of the present invention,

the embossing is elliptical in shape and has a reduced diameter portion at a substantially central portion in the major axis direction.

According to the present invention, it is possible to provide a cleaning wet sheet capable of reducing the occurrence of wiping streaks when a cleaning tool having a head is attached to the cleaning sheet for wiping.

Drawings

Fig. 1 is a perspective view of a cleaning tool to which a cleaning wet sheet according to the present embodiment is attached.

Fig. 2 is a plan view showing the cleaning wet sheet according to the present embodiment.

Fig. 3 is a cross-sectional view of section III-III of fig. 2.

Fig. 4 is a plan view showing a cleaning wet sheet according to a modification.

Fig. 5A is a plan view showing an embossed pattern of the embodiment.

Fig. 5B is a plan view showing an embossed pattern of the embodiment.

Fig. 5C is a plan view showing an embossed pattern of the comparative example.

Fig. 5D is a plan view showing an embossed pattern of the comparative example.

Detailed Description

Hereinafter, a cleaning wet sheet 100 according to an embodiment of the present invention will be described with reference to the drawings. However, the scope of the invention is not limited to the examples shown in the drawings, but is always determined based on the description of the scope of patent claims.

In the following, the X direction, Y direction, and Z direction are specified as shown in fig. 1. In the present specification, "to" is used in a meaning including numerical values before and after the "to" as a lower limit value and an upper limit value.

[ constitution of embodiment ]

Fig. 1 is a view showing a state of the cleaning wet sheet 100 according to the present embodiment in use.

As shown in fig. 1, the cleaning wet sheet 100 is a sheet obtained by impregnating a raw paper sheet obtained by laminating a plurality of fiber collecting substrates with a chemical solution. For example, the cleaning tool 200 is interchangeably attached to the cleaning tool 200 for cleaning a floor, and the cleaning tool 200 includes a rectangular flat plate-shaped head 201 and a handle 202 attached to the upper surface of the head 201.

As shown in fig. 2, the cleaning wet sheet 100 is in the following state: the cleaning surface is formed by covering the bottom surface of the head 201 of the cleaning tool 200, and is folded along the longitudinal edge 201a of the head 201 of the cleaning tool 200 along the folding line S and is locked to the upper surface of the head 201.

The long side edge 201a is an edge along the long side direction of the head 201. Namely, the longer 2 edge portions out of the 4 edge portions of the rectangular head 201.

The fiber collecting base material is a nonwoven fabric produced by bonding predetermined fibers to each other by a known technique such as hydroentanglement, hot air, air-laying, spot bonding, spunbond, or needle punching.

Fig. 3 is a cross-sectional view of line III-III of fig. 2.

As shown in fig. 3, the cleaning wet sheet 100 has a 3-layer structure, for example, the surface layers on both sides are hydrophobic fiber layers 11 and 11 composed mainly of hydrophobic fibers, and the middle layer is a hydrophilic fiber layer 12 composed mainly of hydrophilic fibers. The boundary regions between the fibers of the hydrophobic fiber layers 11 and the fibers of the hydrophilic fiber layer 12 are formed so that the fibers are interwoven with each other.

Therefore, the chemical solution impregnated in the hydrophilic fiber layer 12 in the middle layer is less likely to be released to the surface to be cleaned adjacent to the hydrophobic fiber layer 11 in the surface layer, and the chemical solution can be selectively released to the floor surface. Therefore, release of the chemical liquid ineffective for cleaning can be suppressed.

In addition, the hydrophobic fibers and the hydrophilic fibers are respectively interwoven, so that the air held in the interwoven portion can further improve the holding property of the chemical solution.

(hydrophilic fiber)

As the hydrophilic fiber, natural fibers such as cotton, pulp, and hemp, regenerated fibers such as rayon, and cuprammonium fibers, and the like can be used. Among them, pulp, rayon, polypropylene spunbond fibers (PPSB) and the like are preferably used from the viewpoint of maintaining water retention in particular.

(hydrophobic fiber)

Examples of the hydrophobic fibers include polyolefin fibers such as Polyethylene (PE), polypropylene (PP) and polyvinyl alcohol, polyester fibers such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), and acrylic fibers. They may be used alone or in combination of 2 or more. Examples of the composite fibers of 2 or more types include a core-sheath type in which a resin having a relatively low melting point (low melting point resin) is used as a sheath portion and a resin having a relatively high melting point (high melting point resin) is used as a core portion, a side-back type in which a low melting point resin and a high melting point resin are arranged in a predetermined direction, and the like.

(weight per unit area)

Cleaning according to the inventionIn the case of the wet sheet 100, the weight per unit area is preferably 30g/m ² ～120g/m ² Particularly preferably 60g/m ² ～100g/m ² Left and right. If the weight per unit area is less than 30g/m ² The dirt holding ability is insufficient, and the cleaning sheet 100 tends to be twisted and unstable during cleaning. In addition, if it exceeds 120g/m ² The flexibility is insufficient, and it is difficult to attach the cleaning wet sheet 100 to the cleaning tool 200.

(CNF)

Further, cellulose Nanofibers (CNF) may be added to the cleaning wet sheet 100.

CNF is a cellulose fiber obtained by defibrating pulp fibers and generally comprising cellulose microfibers having a fiber width of nanometer size (1 nm to 1000 nm), and preferably has an average fiber width of 100nm or less. For example, a certain number of number average, median, mode diameter (mode) and the like are used for calculating the average fiber width.

The CNF may be impregnated uniformly in the thickness direction of the base paper sheet, but it is preferable that the content of CNF gradually increases from the center in the thickness direction of the base paper sheet to the front and back surfaces. Thus, the cleaning sheet 100 is less likely to break even when the cleaning surface or the like is strongly rubbed.

(pulp fiber capable of being used for CNF)

Examples of pulp fibers that can be used for producing CNF include mechanical pulp such as hardwood pulp (LBKP), conifer pulp (NBKP), chemical pulp such as bleached thermo-mechanical pulp (BTMP), millboard pulp (SGP), pressboard (PGW), refined millboard pulp (RGP), chemical millboard pulp (CGP), thermowood pulp (TGP), crushed wood pulp (GP), thermomechanical pulp (TMP), chemical thermomechanical pulp (CTMP), and Refined Mechanical Pulp (RMP), mechanical pulp such as brown waste paper, waste kraft envelopes, waste magazines, waste newspapers, waste handpieces, office waste paper, old corrugated paper, white waste paper such as upper white Gu), kent waste paper, imitation waste paper, ground contract waste paper, low-grade printed waste paper (more ancient waste paper), and deinked waste paper pulp obtained by deinking waste paper pulp (DIP) produced by deinking waste paper pulp. They may be used alone or in combination of plural kinds as long as the effects of the present invention are not impaired.

(method for defibration of CNF)

As a defibration method used for the production of CNF, for example, mechanical methods such as a high-pressure homogenizer method, a microfluidizer method, a mill grinding method, a bead mill freeze-pulverizing method, and an ultrasonic defibration method are mentioned, but the method is not limited to these methods.

The CNF subjected to only mechanical treatment (not modified) by the above-described defibration method or the like, that is, the CNF not modified with a functional group, has high thermal stability as compared with the CNF modified with a functional group such as a phosphate group or a carboxymethyl group, and thus can be used for a wider range of applications, but the CNF modified with a functional group such as a phosphate group or a carboxymethyl group can also be used for the present invention.

For example, CNF obtained by subjecting pulp fibers to a mechanical defibration treatment may be subjected to a chemical treatment such as carboxymethylation or an enzymatic treatment. Examples of chemically treated CNF include TEMPO-oxidized CNF, phosphorylated CNF, and phosphitylated CNF, etc. of iCNF (individualized CNF) (monocellulose) having a diameter of 3nm to 4 nm.

The CNF may be a CNF subjected to chemical treatment or enzymatic treatment alone or a CNF subjected to mechanical defibration treatment.

[ liquid medicine ]

The cleaning wet sheet 100 of the present embodiment is impregnated with a predetermined chemical solution containing adjuvants such as glycol ethers, aqueous cleaning agents, preservatives, degerming agents, lower alcohols, and organic solvents. The liquid chemical is impregnated by 100 to 500 mass%, preferably 150 to 300 mass%, relative to the mass of the base paper sheet as the base material of the cleaning wet sheet 100.

The chemical solution is impregnated into the dried raw paper sheet, and the chemical solution impregnated into the hydrophilic fiber layer 12 is released from the hydrophobic fiber layer 11 on the front or back surface when the cleaning wet sheet 100 is used.

[ embossing ]

As shown in fig. 1 and 2, the cleaning wet sheet 100 is provided with embossments 20, and the embossments 20 are portions for compressing the sheet in the Z direction.

For example, as shown in fig. 2, the embossing 20 is formed in a so-called gourd shape having an elongated elliptical shape short in one direction and narrow in width and having a reduced diameter portion at a substantially central portion in the long axis direction in a plan view. The shape of the embossment 20 is not limited to this, and may be, for example, various shapes such as a polygon, or a combination of shapes. However, such a gourd shape is preferable from the viewpoint of improving the erasability of dirt.

The embossing 20 may be formed by, for example, hot embossing under conditions of a temperature of 80 to 200 ℃ and an embossing pressure of 0.2 to 1.0 MPa. When embossing 20 is formed by hot embossing, a roller having at least an outer peripheral surface made of a cured resin such as carbon steel, stainless steel, polypropylene, ABS (Acrylonitrile Butadiene Styrene) resin, or the like can be used as the embossing roller. Among them, a roll made of stainless steel is preferably used, particularly from the viewpoints of durability and heat resistance.

In addition, when embossing is performed by hot embossing, it is preferable to perform the step of impregnating the cleaning wet sheet 100 with the chemical solution before the step, in view of easily imparting the uneven shape.

(embossing, debossing)

As the embossments 20, there are formed convex embossments 21 that are convex on the upper side in the Z direction (the 1 st surface side of the cleaning wet sheet 100) and concave embossments 22 that are convex on the lower side (the 2 nd surface side of the cleaning wet sheet 100) (i.e., concave on the upper side in the Z direction). In each drawing, the convex embossment 21 is shown by a solid line, and the concave embossment 22 is shown by a broken line.

The embossment 21 is formed to have a length of 5mm to 10mm, preferably 6mm to 8mm, in the longitudinal direction. The length of the thin film is 2mm to 5mm, preferably 3mm to 4mm, in the short axis direction perpendicular to the long axis direction. The Z-direction is formed (height from the intermediate portion (described later)) to be 0.5mm to 2mm, preferably 0.7mm to 1.5mm. The concave embossing 22 is formed in a shape that is substantially the same as the convex embossing 21 in a vertically opposite direction in a cross-sectional view, and is formed in a shape that protrudes toward the lower side in the Z direction.

(middle part)

An intermediate portion is formed between the embossments 20 formed in the cleaning sheet 100. The intermediate portion is a portion where the embossment 20 is not formed, and therefore is located lower than the convex embossment 21 and higher than the concave embossment 22 in the Z direction.

[ embossing Pattern ]

In the cleaning wet sheet 100 of the present embodiment, for example, as shown in fig. 2, the 1 st embossed block 30 in a diamond shape, which is formed by a combination of the convex embossments 21 and the concave embossments 22, in which the angle between the 1 st direction (X direction in fig. 2) orthogonal to the 1 st side a and the long axis direction is 30 ° to 60 °, is continuously formed into the embossed block row 31 from the 1 st side a to the 2 nd side b. The embossed block row 31 is arranged in series from the 3 rd side c to the 4 th side d, and among the 1 st embossed block row 31 and the 2 nd embossed block row 31 which are adjacent to each other, the 1 st embossed block 30 in the 1 st embossed block row 31 and the 2 nd embossed block 30 which is adjacent to each other in the 2 nd embossed block row 31 are arranged so as to overlap each other in the 2 nd direction (Y direction in fig. 2) which is orthogonal to the 1 st direction, and at least one of the male embossments 21 and the female embossments 22 is present on a straight line which extends vertically from an arbitrary point on the 3 rd side c to the 4 th side d.

(non-embossed portion)

As shown in fig. 2, the cleaning wet sheet 100 is provided between adjacent embossing blocks 30, and has a non-embossed portion 40 which is not compressed in the Z direction and has fuzzing.

The non-embossed portion 40 may be formed as follows: the embossing roll forming the embossment 20 is designed in such a way as to remove the shape of the non-embossment 40 or is slightly compressed to the extent of residual fuzzing as compared to the compressed portion of the embossment 20.

By setting the area of the non-embossed portion 40 to be 25% to 50% relative to the cleaning wet sheet 100, the occurrence of wiping streaks can be reduced, and the cleaning wet sheet 100 excellent in wiping performance can be produced.

When the cleaning tool 200 is attached to the cleaning wet sheet 100 and the cleaning is performed, the cleaning tool moves substantially perpendicularly to the X direction or the Y direction. However, particularly when the non-embossed portion 40 is formed in a straight line as shown in fig. 2, wiping streaks may be easily generated by moving the cleaning wet sheet 100 at an angle. Therefore, it is more preferable to arrange the embossing blocks 30 such that the non-embossed portions 40 are not linearly arranged.

[ Effect of the invention ]

In general, when wiping is performed by the cleaning tool 200 having the head 201, the cleaning tool moves in the 1 st direction or the 2 nd direction. However, when the cleaning sheet 100 having the embossed pattern described above and having at least one protruding embossing 21 on a straight line extending perpendicularly from any point on the 3 rd side c to the 4 th side d is attached to the cleaning tool 200, the protruding embossing 21 has overlapping edges when the cleaning tool is wiped in at least the 2 nd direction (Y direction in fig. 2). Therefore, the occurrence of wiping streaks can be reduced.

Further, by providing the non-embossed portions 40 between the embossing blocks 30 in an area of 25% to 50% relative to the cleaning wet sheet 100 instead of providing the embossments 20 on the entire surface of the cleaning wet sheet 100, the embossing embossments 21 protruding more than the non-embossed portions 40 receive a larger pressure when the cleaning wet sheet 100 is used for wiping. Therefore, the release property of the chemical solution is improved, and the occurrence of wiping streaks can be further reduced.

In addition, by the raised embossments 21 receiving a greater pressure, the erasability of the raised embossments 21 improves, and trash is easily accumulated in the non-embossed portions 40. Therefore, the trapping property of the garbage can be improved. In addition, even if the erasability of the embossment 21 and the dust collection performance of the cleaning wet sheet 100 are improved, the non-embossed portion 40 is made less likely to contact the surface to be cleaned by the embossment 21, and accordingly, an increase in the wiping resistance can be suppressed.

In addition, the cleaning wet sheet 100 has a 3-layer structure in which the hydrophilic fiber layer 12 is sandwiched between the hydrophobic fiber layers 11 and 11, and thus the chemical solution held in the hydrophilic fiber layer 12 is selectively released to the surface to be cleaned. In addition, the air held by the portion where the hydrophobic fiber layer 11 and the hydrophilic fiber layer 12 are interwoven can further improve the holding property of the chemical solution.

In addition, when the embossing block 30 is a diamond-shaped embossing block including the embossments 20 having an angle of 30 ° to 60 ° with respect to the longitudinal direction of the 1 st direction, and the embossing block 30 is necessarily arranged offset from the 1 st direction of the cleaning wet sheet 100 when a plurality of embossing block rows 31 are arranged continuously from the 3 rd side c to the 4 th side d, each of the embossing block rows 31 being arranged continuously from the 1 st side a to the 2 nd side b. In addition, when the user performs wiping, a margin is generated by moving the angle of the cleaning wet sheet 100.

Further, the embossing 20 has an elliptical shape and a shape having a reduced diameter portion at a substantially central portion in the major axis direction, whereby the dirt removing performance can be improved.

Modification example

The specific details and the like may be appropriately changed.

For example, the foregoing description has exemplified the embossing block 30 composed of the combination of the convex embossments 21 and the concave embossments 22 for the cleaning wet sheet 100, but is not limited thereto. The embossing block 30 may be provided with at least the embossments 21.

However, providing the concave embossing 22 in the embossing block 30 is preferable because the cleaning wet sheet 100 can be used in opposition to the above, and the cleaning area can be further enlarged.

Fig. 1 and 2 illustrate the diamond-shaped embossed block 30 composed of the embossments 20 having an angle of 30 ° to 60 ° with respect to the 1 st direction and the longitudinal direction, but the shape of the embossed block 30 is not limited thereto. For example, the embossing block 30 may be composed of the embossments 20 having an angle of 0 ° or 90 ° with respect to the 1 st direction and the long axis direction.

Fig. 1 and 2 illustrate examples in which the angles of the major axis directions of the male embossments 21 and the female embossments 22 in the embossing blocks 30 are the same as the 1 st direction, but the present invention is not limited thereto. As shown in fig. 4, the direction of the major axis of the male embossments 21 and the female embossments 22 in the 1 st embossment block 30 may be different from the direction of the major axis of the male embossments 21 and the female embossments 22 in the 2 nd embossment block 30, and the 2 nd embossment block 30 may be adjacent to the 1 st embossment block 30.

The embossments 21 and the concave embossments 22 in the 1 st embossment block 30 may be arranged at different angles.

The chemical solution impregnated in the cleaning wet sheet 100 may be changed according to the application.

The cleaning wet sheet 100 has a 3-layer structure, but is not limited thereto.

In each of the drawings, the 1 st side a and the 2 nd side b are short sides of the cleaning wet sheet 100, and the 3 rd side c and the 4 th side d are long sides of the cleaning wet sheet 100, but the present invention is not limited thereto.

In each of the drawings, the convex embossment 21 and the concave embossment 22 have substantially the same gourd shape in plan view, but the convex embossment 21 and the concave embossment 22 may have different shapes.

However, in any of the above-described embossed patterns, it is preferable that the convex embossments 21 and the concave embossments 22 are arranged in the cleaning wet sheet 100 so as to be substantially symmetrical to each other on the 1 st and 2 nd surfaces. Thus, the cleaning wet sheet 100 has the same level of cleaning function on the 1 st surface and the 2 nd surface, and the cleaning area per 1 sheet can be increased.

Examples

Next, results obtained by evaluating preferred configurations will be described with respect to examples and comparative examples of the present invention. Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples.

[ sample preparation ]

First, a weight per unit area of 40g/m was produced ² ～50g/m ² 2 hydrophobic fiber layers composed of 80% PET and 20% PP/PE binder, and weight per unit area of 40g/m ² ～50g/m ² And 1 piece of hydrophilic fiber layer composed of pulp 70% and PPSB 30%. Then, the hydrophilic fiber layers were woven by a water-jet weaving method so that both sides of the hydrophilic fiber layers were sandwiched between the hydrophobic fiber layers, and cut into 300mm×200mm pieces, to prepare 1 base paper sheet.

Next, the base paper sheet was subjected to hot embossing at a temperature of 95 ℃ and an embossing pressure of 0.4MPa so as to form an embossed pattern of examples 1 to 3 and comparative examples 1 to 3, to prepare test pieces.

Example 1 non-embossed portion 25%

As shown in fig. 2, a plurality of diamond-shaped 1 st embossing blocks 30 each composed of a combination of a convex embossing 21 and a concave embossing 22 each having a gourd shape and having an angle of 30 ° with respect to the longitudinal direction in the 1 st direction (X direction in fig. 2) are arranged continuously from the 1 st side a to the 2 nd side b opposed to the 1 st side a, and a plurality of embossing block rows 31 are arranged continuously from the 3 rd side c to the 4 th side d. At this time, among the 1 st embossing block row 31 and the 2 nd embossing block row 31 which are adjacent, the 1 st embossing block 30 in the 1 st embossing block row 31 and the 2 nd embossing block 30 in the 2 nd embossing block row 31 are overlapped in the 1 st direction, the embossments 20 are arranged so that at least one embossment 21 is present on a line extending vertically from an arbitrary point on the 3 rd side c to the 4 th side d, and the non-embossed portions 40 are provided between the respective embossing blocks 30 so as to be 25.0% with respect to the area of the base paper sheet.

EXAMPLE 2 non-embossed portion 37.5%

As shown in fig. 5A, the non-embossed portion 40 was provided so as to be 37.5% with respect to the area of the base paper sheet.

Other conditions were the same as in example 1.

EXAMPLE 3 non-embossed portion 50%

As shown in fig. 5B, the non-embossed portion 40 was provided so as to be 50.0% with respect to the area of the base paper sheet.

Other conditions were the same as in example 1.

Comparative example 1 non-embossed portion 0% in-line arrangement

As shown in fig. 5C, a test piece having no non-embossed portion 40 was produced by alternately arranging embossed and debossed portions of a gourd shape having a longitudinal direction parallel to the 1 st direction over the entire surface of the base paper sheet.

Comparative example 2 non-embossed portion 0%, saw tooth shape

A plurality of 1 st convex embossments and 2 nd convex embossments are provided in which the embossments of the calabash shape are arranged, and the directions of the long axis directions are different, wherein the 1 st convex embossments adjacent to each other in the short axis direction are arranged in a mode that part of the two 1 st convex embossments are overlapped in the short axis direction and are staggered in the long axis direction, and the 2 nd convex embossments adjacent to each other in the short axis direction are arranged in a mode that part of the two 2 nd convex embossments are overlapped in the short axis direction and are staggered in the long axis direction.

The 1 st embossment and the 2 nd embossment are arranged continuously from the 1 st side a of the base paper sheet to the 2 nd side b facing the 1 st side a so that the 1 st embossment and the 2 nd embossment are adjacent to each other at a substantially right angle in the longitudinal direction.

In addition, concave embossments were arranged in the same embossing pattern as the convex embossments in an alternating manner, and a test piece having no non-embossed portion 40 as shown in fig. 5D was produced.

Comparative example 3 non-embossed portion 100%

The test piece having only the non-embossed portion 40 was produced without embossing.

The test pieces of examples 1 to 3 and comparative examples 1 to 3 were each impregnated with a chemical solution containing an aqueous cleaning agent, a preservative, a degerming agent and alcohol in an amount of 300 mass% based on the dry weight, to prepare wet pieces of examples 1 to 3 and comparative examples 1 to 3. Then, these wet sheets were attached to a cleaning tool having a flat head of 250mm×100mm, respectively, to prepare wipers with wet sheets of examples 1 to 3 and comparative examples 1 to 3.

The following tests 1 to 3 were conducted using the wet sheet-carrying wipers of examples 1 to 3 and comparative examples 1 to 3 described above.

[ test 1. Wiping streak test ]

(1) The wiper with wet sheet, in which a weight was placed so that the total weight became 400g, was placed on the right end of the blackboard with the head facing.

(2) The weight and the wiper with the wet sheet were pressed and moved 300mm from the right end to the left end of the blackboard.

(3) The state in which almost no wiping streak was generated on the cleaning surface (the wet area was about 90% to 100% of the entire cleaning surface) was good, the state in which a small amount of wiping streak was generated (the wet area was about 80% to 90% of the entire cleaning surface) was delta, and the state in which many wiping streaks were generated (the wet area was 80% or less of the entire cleaning surface) was evaluated by visual observation.

[ test 2. Test of wiping Performance ]

(1) 15ml of beef tallow were added dropwise to a 480mm X320 mm stainless steel plate: olive oil: chloroform: fluorescent paint = 12.5:12.5:74.4:0.6 The scale was simulated and developed in the proportion of (mass ratio), and the scale was dried for 5 minutes by a hot air dryer (temperature 60 ℃) to measure the weight of the stainless steel plate.

(2) A wiper with wet sheets, in which a weight was placed so that the total weight became 500g, was placed on the right end of the stainless steel plate with the head facing.

(3) The weight and the wiper with wet sheet were pressed against each other and the left end was moved from the right end of the stainless steel plate, and the stainless steel plate was dried again with a hot air dryer (temperature 60 ℃) for only 5 minutes, and the weight was measured.

(4) The wiping amount of each cleaning wet sheet was calculated from the difference between the weight of the stainless steel sheet before the test measured in (1) and the weight of the stainless steel sheet after the test measured in (3).

(5) The operations (1) to (4) were performed 2 times, and the average value of the wiping amounts was calculated.

[ test 3. Test for wiping resistance ]

(1) A wet sheet wiper having a weight of 500g in total was placed on a laminate floor with its head facing.

(2) A hole was bored in the head connecting portion of the wiper body, and a push-pull gauge ((DS 2-200N manufactured by IMADA Co., ltd.) was attached to the hole.

(3) The maximum resistance value when the wet sheet wiper equipped with a push-pull gauge was pulled by 50cm was measured.

(4) The operation (3) was performed 5 times, and the average value of the wiping resistance was calculated.

The results of runs 1-3 are shown in Table I.

TABLE 1

TABLE I

[ evaluation ]

When the results of test 1 were compared, it was found that examples 1 to 3 provided with the non-embossed portions 40 reduced the occurrence of wiping streaks as compared with comparative examples 1 and 2 in which the non-embossed portions 40 were not provided. This is considered to be because the pressure applied to the embossment 21 increases in response to the provision of the non-embossed portion 40, and the release of the chemical liquid improves.

On the other hand, when examples 1 to 3 and comparative example 3 were compared, it was found that the occurrence of wiping streaks slightly increased as the proportion of the non-embossed portions 40 increased. This is considered to be because as the proportion of the non-embossed portions 40 increases, the number of the embossments 21 decreases accordingly, the contact area with the blackboard decreases, and the release of the chemical liquid decreases.

When the results of test 2 were compared, it was found that the wiping amount of examples 1 to 3 provided with the non-embossed portions 40 was increased compared with comparative examples 1 and 2 in which the non-embossed portions 40 were not provided, and thus the wiping performance was improved.

On the other hand, when comparing examples 1 to 3, it was found that example 1 provided with 25% of the non-embossed portions 40 was able to wipe the most dirt, and as the non-embossed portions 40 increased, the amount of dirt wiped decreased. This is considered to be because as the proportion of the non-embossed portions 40 increases as described above, the number of embossments 21 relatively decreases, and the release property of the chemical and the erasability of dirt decrease.

In addition, when comparing the results of test 3, it was found that the wiping resistance of comparative example 3 in which no embossed portion 20 was provided only over the entire surface was increased, but in comparative examples 1 and 2 in which no non-embossed portion 40 was provided and examples 1 to 3 in which no non-embossed portion 40 was provided, no significant difference in wiping resistance was observed.

This is considered to be because the non-embossed portion 40 is less likely to contact the surface to be cleaned, and the wiping resistance of the entire cleaning wet sheet 100 does not vary greatly.

Industrial applicability

The present invention can be used for a cleaning wet sheet that can reduce the occurrence of wiping streaks when a cleaning tool having a head is attached to the cleaning sheet for wiping.

Symbol description

100 wet sheet for cleaning

11 hydrophobic fiber layer

12 hydrophilic fibrous layer

20 embossing

21 embossing

22 concave embossing

30 embossing block

31 embossing block row

40 non-embossed portions

200 cleaning tool

201 head

a 1 st side

b 2 nd side

c 3 rd edge

d 4 th side

Claims

1. A cleaning wet sheet is formed by impregnating a raw paper sheet with a chemical solution, and is used by being attached to a cleaning tool having a head,

the cleaning wet sheet is provided with an embossing block formed by integrating a plurality of convex embossments, wherein the convex embossments are embossments protruding from the 1 st surface of the cleaning wet sheet,

a non-embossed portion in which the embossing is not arranged is provided between the embossing block and the adjacent other embossing block,

the embossed block row is arranged in plural from the 3 rd side orthogonal to the 1 st side to the 4 th side opposite to the 3 rd side,

the embossments are arranged such that at least one exists on a straight line extending vertically from any point on the 3 rd side to the 4 th side.

2. The cleaning wet sheet according to claim 1, wherein the cleaning wet sheet comprises concave embossments protruding from a 2 nd surface of the cleaning wet sheet

The embossing block is composed of a combination of a plurality of the male embossments and the female embossments,

the intaglio embossing is arranged in such a manner that there is at least one on a line extending from any point on the 3 rd side to the 4 th side.

3. The cleaning wet sheet according to claim 1 or 2, wherein the base paper sheet comprises a hydrophobic fiber layer forming a surface of the sheet and a hydrophilic fiber layer sandwiched between the hydrophobic fiber layers,

4. The cleaning wet sheet according to any one of claims 1 to 3, wherein an angle between a major axis direction of the embossment and a 1 st direction is 30 DEG or more and 60 DEG or less, the 1 st direction is orthogonal to the 1 st side,

the embossing block is diamond-shaped.

5. The cleaning sheet according to any one of claims 1 to 4, wherein the embossment has an elliptical shape and has a reduced diameter portion at a substantially central portion in the longitudinal direction.