Cleaning sheet, laminate of cleaning sheet, cleaning tool, and manufacturing method of cleaning sheet

Abstract

To provide a cleaning sheet, etc., which are at least provided with superior dust trapping ability.SOLUTION: A cleaning sheet is formed of a cleaning surface which is to be in sliding contact with the surface of a body to be cleaned. The cleaning surface is provided with irregularity, with the tip of a protrusion in sliding contract with the body to be cleaned. The protrusion is formed so that a space is made in the surface direction of the cleaning surface. The cleaning surface has higher adhesion than the protrusion and is further provided with an adhesive recess which is exposed on the cleaning surface. The adhesive recess is provided with an adhesive layer, and the rate of the exposed area of the adhesive layer in the cleaning surface is 30% or more. A ratio H / L, between the average protrusion height H from the tip of the protrusion to the adhesive recess and an average length L of the shape of the adhesive recess in a first direction in which the average length of the space in the surface direction is minimized, is 15×10-3 or higher.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a cleaning sheet, a laminate of cleaning sheets, a cleaning tool including a cleaning sheet, and a method for producing a cleaning sheet. [Background technology]

[0002] Various cleaning tools (wiping tools) for cleaning floor surfaces such as hardwood floors are widely known. This type of cleaning tool, for example, includes a head attached to the end of a rod-shaped handle and a cleaning sheet that can be attached and detached to the head, and is used by fixing the cleaning sheet to the head (Patent Document 1). The cleaning tool described in Patent Document 1 can capture dirt (objects to be removed) on a surface to be cleaned, such as a floor, by sliding one side (cleaning side) of the cleaning sheet against the surface of the surface to be cleaned. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 9-220191 Summary of the Invention [Problem to be solved by the invention]

[0004] The cleaning sheet described in Patent Document 1, which is fixed to a cleaning tool for use, includes a fiber sheet having fibers assembled therein. More specifically, the cleaning sheet described in Patent Document 1 includes an outermost fiber sheet having a plurality of holes formed therethrough in the thickness direction, and an adhesive layer superimposed on the fiber sheet. The cleaning sheet described in Patent Document 1 can scrape off and capture dirt by utilizing the fine fiber structure of the fiber sheet. Furthermore, if dirt gets into the holes, the trapped dirt can be captured by the adhesive force of the surface of the adhesive layer, and the captured state can be maintained. However, in the cleaning sheet described in Patent Document 1, holes are simply formed in the fiber sheet, so it cannot be said that the adhesive layer can effectively capture dirt in the depressions of the holes. In other words, the performance of capturing dirt by the adhesive layer in the holes is not necessarily good. Therefore, conventional cleaning sheets such as those disclosed in Patent Document 1 have the problem that they do not have good dirt trapping properties.

[0005] In view of the above problems, an object of the present invention is to provide a cleaning sheet having at least good dirt trapping properties, and a cleaning tool provided with the cleaning sheet. [Means for solving the problem]

[0006] The cleaning sheet according to the present invention is a cleaning sheet having a cleaning surface that is brought into sliding contact with the surface of an object to be cleaned, The cleaning surface has projections and recesses, and is used by bringing tips of the projections into sliding contact with the object to be cleaned; the protrusions are formed of members spaced apart from one another in a surface direction of the cleaning surface, the cleaning surface further has an adhesive recess having a higher adhesive strength than the member and exposed on the cleaning surface; an adhesive layer extending in a surface direction of the cleaning surface and disposed in at least a part of the space between the members, at least a part of the adhesive layer constituting the adhesive recess, and a ratio of an exposed area of ​​the adhesive layer to the cleaning surface being 30% or more; The ratio (H / L) of the average convex height (H: mm) from the tip of the convex portion to the adhesive concave portion to the average length (L: mm) of the shape of the adhesive concave portion in the first direction in which the average length of the interval in the surface direction is the smallest is 15×10 -3 That's all.

[0007] The cleaning sheet of the above configuration has an uneven cleaning surface, and is used by mainly sliding the tips of the protrusions against the object to be cleaned. Since the ratio of the exposed area of ​​the adhesive layer is 30% or more, the adhesive recesses can sufficiently capture dirt. In addition, the ratio (H / L) of the average height of the protrusions (H: mm) to the average length (L: mm) of the shape of the adhesive recesses is 15×10 -3 For the above reasons, the tips of the protrusions can slide while preventing the adhesive recesses from coming into contact with the surface of the object to be cleaned. Thus, while the protrusions are in sliding contact with the object to be cleaned, dirt can be collected in the gaps between the members that make up the protrusions. Since the adhesive recesses, which are more recessed than the protrusions and have relatively high adhesive strength, are arranged in the above-mentioned gaps, the collected dirt can be captured by the adhesive recesses. Moreover, the captured dirt can be held on the surface of the adhesive recesses by their adhesive strength. Therefore, the above-mentioned cleaning sheet has good dirt collection properties.

[0008] In the cleaning sheet, the proportion of the exposed area of ​​the adhesive layer on the cleaning surface may be greater than 50%, which allows the cleaning sheet to have better dirt trapping properties.

[0009] In the above cleaning sheet, the average convex height (H) is 1000×10 -3 It is preferable that the size is less than 500×10 -3 More preferably, it is 300×10 mm or less. -3 It is more preferable that the thickness is less than or equal to mm. The average convex height (H) is 500×10 -3 By making the thickness of the adhesive recess smaller than 1 mm, the depth of the recess from the tip of the convex portion to the adhesive recess becomes shallower. Therefore, the adhesive recess can approach closer to the surface of the object to be cleaned during sliding contact. Therefore, the adhesive recess can capture dirt relatively easily and more sufficiently. Therefore, the above cleaning sheet has better dirt capture properties.

[0010] In the above cleaning sheet, the average length (L) of the shape of the adhesive recess in the first direction in which the average length of the interval in the surface direction is smallest is preferably 0.3 mm or more, more preferably 0.5 mm or more, even more preferably 0.8 mm or more, and particularly preferably 1.0 mm or more. By setting the average length (L) of the shape of the adhesive recesses to 0.3 mm or more, the average size of each adhesive recess is relatively large, which allows the adhesive recesses to capture dirt more effectively, and therefore the cleaning sheet has better dirt capture properties.

[0011] In the above cleaning sheet, the minimum load of the load curve when the member of the convex portion is measured by nanoindentation is preferably −0.40 μN or more and 0 μN or less, and more preferably −0.10 μN or more and 0 μN or less. In the above cleaning sheet, the minimum load of the unloading curve when the member of the convex portion is measured by nanoindentation is preferably −1.50 μN or more and 0 μN or less, and more preferably −0.10 μN or more and 0 μN or less. In the above cleaning sheet, it is preferable that the cleaning surface has a static friction coefficient of 1.00 or less. These configurations allow the cleaning sheet to have better slip properties.

[0012] The cleaning sheet has an adhesive layer extending in the surface direction of the cleaning surface and disposed on the back side of the member, a part of the adhesive layer forming the adhesive recess, the hardness of the member measured by a nanoindentation method is 0.4 MPa or more, and the probe tack of the adhesive layer measured by a probe tack method is 1.0 kN / m 2 More than 500.0kN / m 2 It is preferable that: By making the hardness of the member 0.4 MPa or more, the frictional force between the convex parts in sliding contact with the surface of the object to be cleaned and the surface of the object to be cleaned can be made relatively small, and therefore a cleaning sheet having such a member with a relatively high rigidity on its cleaning surface has good slip properties. The probe tack of the adhesive layer is 1.0 kN / m 2 More than 500.0kN / m 2 By satisfying the above condition, better dust trapping properties can be achieved. Therefore, the hardness of the member constituting the protrusion is 0.4 MPa or more, and the probe tack of the adhesive layer is 1.0 kN / m 2 More than 500.0kN / m 2 By satisfying the above condition, it is possible to exhibit good dirt trapping properties while also exhibiting good slip properties.

[0013] In the above cleaning sheet, it is preferable that the material of the protrusions contains at least one of wax, hardened resin, and inorganic powder.

[0014] In the above cleaning sheet, the material of the convex portion may contain at least one of polyolefin resin, ethylene-vinyl acetate copolymer resin (EVA), styrene-based thermoplastic elastomer resin, acrylic resin, polyvinyl chloride resin, polyester resin, polyurethane resin, polyimide resin, polyamide resin, and polycarbonate resin.

[0015] In the above cleaning sheet, the members of the convex portions may contain an extender pigment as the inorganic powder.

[0016] In the above cleaning sheet, the cleaning surface may be formed on both sides.

[0017] The method for producing a cleaning sheet according to the present invention is the method for producing the above-mentioned cleaning sheet, The member of the protrusion is formed by coating.

[0018] In the above-mentioned method for producing a cleaning sheet, the cleaning sheet may have a supporting substrate, and the members of the protrusions may be formed by overlaying the supporting substrate by coating. In the above-mentioned method for producing a cleaning sheet, the cleaning sheet may have a supporting substrate and an adhesive layer overlying the supporting substrate, and the members of the convex portions may be formed by overlaying the adhesive layer by coating.

[0019] The laminate of the present invention is in a state where the cleaning sheet is rolled up, or The cleaning sheet is characterized in that a plurality of the above cleaning sheets are laminated in the thickness direction.

[0020] The cleaning tool of the present invention comprises the above-mentioned cleaning sheet and a sheet fixing part to which the cleaning sheet is detachably attached. In the above-mentioned cleaning tool, any one of the above-mentioned cleaning sheets is detachably attached to the sheet fixing part. During cleaning, the sheet fixing part is operated in the same manner as a mop or floor wiper, for example, to bring the cleaning sheet attached to the sheet fixing part into sliding contact with the surface of the object to be cleaned, thereby efficiently carrying out the cleaning work. Effect of the Invention

[0021] The cleaning sheet, the cleaning sheet laminate, and the cleaning tool of the present invention can at least have good dirt trapping properties. The method for producing a cleaning sheet of the present invention has the effect of producing a cleaning sheet having good dirt trapping properties. [Brief description of the drawings]

[0022] [Figure 1] FIG. 2 is a schematic diagram of a cleaning sheet according to an embodiment, viewed from one side (the cleaning side). [Figure 2A] FIG. 2 is a schematic cross-sectional view of the cleaning sheet according to the embodiment, cut in the thickness direction (along the dashed line in FIG. 1). [Figure 2B] FIG. 2B is a schematic cross-sectional view of a cleaning sheet according to another embodiment, cut in the thickness direction as in FIG. 2A. [Diagram 3] FIG. 1 is a perspective view showing a schematic configuration of a cleaning tool to which a cleaning sheet according to an embodiment is attached. [Figure 4] FIG. 11 is a schematic view of a cleaning sheet according to another embodiment, viewed from one side (the cleaning side). [Diagram 5] FIG. 11 is a schematic view of a cleaning sheet according to another embodiment, viewed from one side (the cleaning side). [Figure 6] FIG. 11 is a schematic view of a cleaning sheet according to yet another embodiment, viewed from one side (the cleaning side). [Figure 7] FIG. 1 is a schematic diagram of a cleaning sheet according to a certain embodiment, viewed from one side (the cleaning side). [Figure 8] FIG. 2 is a schematic diagram illustrating a cross section of cleaning sheets stacked in a thickness direction according to an embodiment. [Figure 9A] FIG. 1 is a schematic diagram showing measurement by the nanoindentation method. [Figure 9B] Schematic diagram of a measurement chart using the nanoindentation method. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the cleaning sheet and cleaning tool according to the present invention will be described in detail with reference to the drawings.

[0024] <Cleaning tools> 3, the cleaning tool 100 of this embodiment includes a cleaning sheet 1, which will be described in detail later, and a sheet fixing part 120 that fixes the cleaning sheet 1. Furthermore, the cleaning tool 100 of this embodiment includes a rod-shaped grip member 110 that functions as a handle. The sheet fixing part 120 is flat to hold the cleaning surface 10 of the cleaning sheet 1 in a flat state, and is rotatably connected to one end of the gripping member 110 via a universal joint 130. In this embodiment, the sheet fixing part 120 is flat and rectangular (oblong) when viewed from one side in the thickness direction. The sheet fixing part 120 is configured so that, with the cleaning sheet 1 fixed, an operator brings at least a part of the cleaning surface 10 of the cleaning sheet 1 into contact with the surface of the object to be cleaned, and slides the cleaning surface 10 in either direction along the surface of the object to be cleaned.

[0025] The cleaning sheet 1 of this embodiment is attached to the sheet fixing part 120, for example, as follows. In detail, a cleaning surface 10 that comes into sliding contact with the object to be cleaned and a non-cleaning surface 20 that does not come into sliding contact are formed on one side of the cleaning sheet 1. The cleaning sheet 1 is placed on one side of the sheet fixing part 120 (a smooth surface that faces the object to be cleaned when used) so that the cleaning surface 10 of the cleaning sheet 1 faces outward. The cleaning sheet 1 is folded back at the edges of the opposing long sides of the sheet fixing part 120, and the portion where the non-cleaning surface 20 is formed is fixed to the other side of the sheet fixing part 120 (the surface that does not face the object to be cleaned). In this embodiment, radial slits 140 are formed in a flexible member on the other side of the sheet fixing part 120. The cleaning sheet 1 can be detachably fixed to the sheet fixing part 120 by pushing a part of the portion where the non-cleaning surface 20 is formed into the radial slits 140. In this manner, the cleaning sheet 1 is detachably attached to the sheet fixing part 120. The fixing means is not limited to this, and known fixing means such as clips can also be used. The cleaning sheet 1 may be attached to the sheet fixing part 120 with double-sided tape or the like. An adhesive layer may be laid over the entire or part of the back side of the cleaning sheet 1, and the adhesive layer may be attached to the sheet fixing part 120. Only one cleaning sheet 1 may be fixed to the sheet fixing part 120, or multiple cleaning sheets 1 may be fixed to the sheet fixing part 120 in a stacked state. When the cleaning sheet 1 becomes damaged or soiled through use and needs to be replaced, it can be easily removed from the sheet fixing part 120. Then, the used cleaning sheet 1 can be replaced with a new, unused cleaning sheet. When a plurality of cleaning sheets 1 are stacked and fixed to the sheet fixing part 120, if the outermost cleaning sheet 1 becomes dirty, the cleaning sheet 1 can be peeled off, for example, along the perforations to expose an unsoiled cleaning sheet 1.

[0026] The cleaning sheet 1 of this embodiment will be described in more detail with reference to the drawings.

[0027] <Cleaning sheet> 1 and 2A, the cleaning sheet 1 of this embodiment has a relatively thin thickness. The cleaning sheet 1 of this embodiment is formed with a cleaning surface 10 that comes into sliding contact with the surface of an object to be cleaned. The cleaning surface 10 has projections and recesses, and is used by bringing the tips of the projections 12 into sliding contact with the object to be cleaned. The projections 12 are composed of members 30 formed to leave a distance A in the surface direction of the cleaning surface 10. The cleaning surface 10 further has adhesive recesses 14 that have a higher adhesive strength than the members 30 and are exposed on the cleaning surface 10. Specifically, the cleaning sheet 1 of this embodiment has a cleaning surface 10 that is in sliding contact with the surface of the object to be cleaned. The cleaning surface 10 has an uneven shape. The cleaning sheet 1 of this embodiment includes an adhesive layer 40 that constitutes at least a part of the bottom of the concave shape, and a convex part component 30 that forms a convex part and has a lower adhesive force than the adhesive layer 40. The convex part component 30 is configured to form a gap in at least one direction of the surface direction of the cleaning surface 10, and the concave shape is disposed in the gap. In the cleaning sheet 1 of this embodiment, the convex part component 30 is disposed so as to protrude from the adhesive layer 40, thereby forming a convex part 12 on the cleaning surface 10. In addition, at least a part of the adhesive layer 40 is disposed on the bottom of the concave shape, thereby forming an adhesive concave part 14. In the adhesive concave part 14, at least a part of the adhesive layer 40 is exposed to the cleaning surface 10. The cleaning sheet 1 of this embodiment includes an adhesive layer 40 that extends in the planar direction of the cleaning surface 10 and is disposed in at least some of the spaces between the members 30. At least some of the adhesive layer 40 constitutes adhesive recesses 14, and the proportion of the exposed area of ​​the adhesive layer 40 on the cleaning surface 10 is 30% or more. The ratio (H / L) of the average convex height (H: mm) from the tip of the convex portion 12 to the adhesive concave portion 14 to the average length (L: mm) of the shape of the adhesive concave portion 14 in the first direction in which the average length of the interval in the above-mentioned surface direction is smallest is 15×10 -3 That's all.

[0028] As shown in FIG. 2A , the cleaning sheet 1 of this embodiment includes the above-mentioned member 30 that is in sliding contact with the object to be cleaned, a supporting substrate 50, and an adhesive layer 40 disposed between the above-mentioned member and the supporting substrate 50. In other words, the cleaning sheet 1 of this embodiment has a support substrate 50 that faces the grip member 110 when fixed to the cleaning tool 100, an adhesive layer 40 superimposed on a portion of the surface of the support substrate 50, and the above-mentioned member 30 superimposed on the surface of the adhesive layer 40. More specifically, the adhesive layer 40 is disposed so as to cover at least a central portion of one surface of the support substrate 50, and the above-mentioned member 30 is disposed so as to superimpose on one surface of the adhesive layer 40 (the surface facing the object to be cleaned). In addition, the number of the above-mentioned members 30 in FIG. 2A is reduced compared to FIG. 1 for ease of viewing.

[0029] As shown in Fig. 1 and Fig. 2A, the cleaning sheet 1 of this embodiment has a cleaning surface 10 formed on one side (the side facing outward when fixed to the sheet fixing part 120) that is in sliding contact with the surface of the object to be cleaned, such as a floor. The cleaning sheet 1 may also have a non-cleaning surface 20 as in this embodiment. In this embodiment, the cleaning surface 10 is formed by the convex parts 12 and parts of the adhesive layer 40 (adhesive concave parts 14), while the non-cleaning surface 20 is formed by the surface of the supporting substrate 50. The non-cleaning surface 20 may be formed by one or more release layers arranged on the surface of the supporting substrate 50. 1, when the rectangular cleaning sheet 1 is viewed from one side, one cleaning surface 10 is disposed between two opposing strip-shaped non-cleaning surfaces 20. In other words, the rectangular cleaning surface 10 is disposed so as to be sandwiched between the two strip-shaped non-cleaning surfaces 20. The cleaning surface 10 may be formed on only one side of the cleaning sheet 1 as described above, or on each of both sides.

[0030] In this embodiment, the convex portion constituent member 30 has a plurality of linear members (linear members). The cleaning surface 10 of the cleaning sheet 1 has the convex portion 12 constituted by members (convex portion constituent members 30) in which a plurality of linear members are arranged at intervals A in the surface direction. In addition, the cleaning surface 10 has the adhesive recessed portions 14 as described above. In this embodiment, the convex component 30 has a plurality of linear members. The linear members are arranged so as to be in contact with the surface of the adhesive layer 40. The linear members are arranged at intervals A along one of the planar directions of the cleaning surface 10. The parallel linear members extend in the same direction as the longitudinal direction of the band-shaped non-cleaning surface 20. The adhesive layer 40 in the adhesive recesses 14 has a higher adhesive strength than the constituent members 30 of the protrusions. At least a part of the adhesive layer 40 is exposed to the cleaning surface 10. In this embodiment, the adhesive recesses 14 are disposed at the above-mentioned interval A, and are recessed from the tips of the protrusions 12 by the protruding height of the protrusions 12. At least a part of the adhesive layer 40 is exposed and forms the bottom of the adhesive recesses 14. With the above-mentioned configuration, the cleaning sheet 1 is used by mainly sliding the tips of the convex parts 12 against the object to be cleaned. During sliding contact, dirt may be collected in the gap A separating the adjacent linear members. In the gap A, the adhesive recesses 14, which have a relatively high adhesive force and are recessed further than the convex parts, are arranged, so that the collected dirt can be captured by the adhesive layer 40 in the adhesive recesses 14. Moreover, even if the captured dirt is relatively heavy, the dirt can be held on the surface of the adhesive recesses 14 by the adhesive force. Therefore, the above-mentioned cleaning sheet has good dirt-capturing properties. Furthermore, with the above-mentioned configuration, although the adhesive layer 40 has a relatively strong adhesive force, the adhesive recesses 14 are recessed below the tips of the protrusions 12, so that the cleaning surface 10 is not significantly affected by the frictional force caused by the adhesive force of the adhesive layer 40, and mainly the tips of the protrusions 12 come into contact with and slide against the surface of the object to be cleaned. Therefore, the above-mentioned cleaning sheet 1 has good slip properties.

[0031] The static friction coefficient of the cleaning surface (vs. SUS304 plate) is preferably 3.00 or less, more preferably 1.50 or less, and even more preferably 1.00 or less. This allows for better slipperiness. The static friction coefficient may be 0.20 or more. The static friction coefficient is measured in accordance with the measurement conditions described in JIS K7125:1999 (ISO8295:1995) at a temperature of 23°C. Similarly, the coefficient of kinetic friction can be determined. The friction coefficient was measured using a SUS304 steel plate (100 x 200 mm) as specified in JIS Z0237:2009. A sheet measuring 80 x 160 mm cut from a cleaning sheet was placed on top of the SUS304 steel plate so that the cleaning surface was in contact with the SUS steel plate surface, with a contact area of ​​40 cm. 2A sliding piece (63 mm on each side) is placed on the plate. The total mass of the sliding piece is adjusted to 200 g. The friction coefficient measurement is performed at a speed of 100 mm / min, and the static and kinetic friction coefficients are calculated based on the maximum force over a measurement distance of 60 mm. The average value of each of the five measurements is recorded. When measuring the static friction coefficient, the auxiliary plate is connected to the load cell via a spring, but when measuring the kinetic friction coefficient, no spring is used. The static and dynamic friction coefficients can be reduced, for example, by increasing the ratio (H / L) described below, where the ratio (H / L) is the ratio (H:mm) of the average convex height from the tip of the convex portion 12 to the adhesive concave portion 14 to the average length (L:mm) of the shape of the adhesive concave portion in the first direction in which the average length of the interval in the surface direction of the cleaning surface is the smallest.

[0032] (Materials that make up the convex portion) In this embodiment, the member 30 constituting the protrusion has a plurality of linear members extending in parallel. A part of the adhesive layer 40 is exposed in the space A between the adjacent linear members. This allows the adhesive layer 40 to capture dust that has gathered near the adhesive recess 14 due to sliding contact, and the dust can be kept captured by the adhesive force of the adhesive recess 14. Therefore, good dust capture properties are exhibited.

[0033] The width of the line member is usually 0.01 mm or more. The width of the line member is more preferably 0.02 mm or more, further preferably 0.03 mm or more, and particularly preferably 0.1 mm or more. The width of the line member may be 20 mm or less, 10 mm or less, 5 mm or less, or 1 mm or less. When the convex portion is composed of a plurality of parallel line members or a plurality of intersecting line members, it is preferable that the width of the line member is within the above range.

[0034] The hardness of the member 30 constituting the protrusions is measured by a nanoindentation method. The hardness is preferably 0.4 MPa or more. When the hardness is 0.4 MPa or more, the frictional force between the protrusions 12 that slide against the surface of the object to be cleaned and the surface of the object to be cleaned during sliding contact can be made relatively small. Therefore, the cleaning sheet 1 having such a member with a relatively high rigidity on the cleaning surface 10 has good slip properties. In addition, by forming the protrusions 12 from such a member with a relatively high rigidity, wear of the member due to sliding contact during cleaning is suppressed, and the cleaning sheet 1 can exhibit good durability. The hardness of the component 30 of the convex portion is preferably 0.4 MPa or more, more preferably 1.5 MPa or more, even more preferably 3.0 MPa or more, particularly preferably 5.0 MPa or more, and most preferably 10.0 MPa or more. There is no particular upper limit to the hardness of the component, and the hardness of the component may be 200 MPa or less. In order to impart appropriate deformability to the component 30 and to prevent the convex portion 12 from causing scratches on the surface of the object to be cleaned, the hardness of the component 30 is preferably 100 MPa or less, more preferably 70 MPa or less, and particularly preferably 50 MPa or less.

[0035] The hardness of the member 30 by the nanoindentation method is measured in accordance with ISO14577. Specifically, it is measured by a measuring device "TI950 TriboIndenter" (manufactured by Hysitron). More specifically, it is calculated by dividing the "load (maximum load Pmax) when the indenter is pressed deepest" by the "area where the indenter and the measurement sample contact (contact projected area B)". A Berkovich type diamond indenter (triangular pyramid indenter) is used as the indenter, and a single indentation measurement is performed. In order to prevent the measured value from being affected by anything other than the member 30, it is desirable that the thickness of the member 30 at the time of measurement is at least 50 μm. The indenter pressing speed is 500 nm / sec, and the pulling speed is 500 nm / sec. The indenter pressing depth is 5 μm. The measurement is performed at 25° C. At least three measurements are performed to obtain an average value. The examples described later are also measured in the same manner.

[0036] The elastic modulus of the member 30 measured by the nanoindentation method may be, for example, 4.5 MPa or more and 1000 MPa or less, 4.5 MPa or more and 500 MPa or less, or 4.5 MPa or more and 200 MPa or less. The elastic modulus is calculated based on the results of measurement in the same manner as the measurement of the hardness of the member 30. However, the elastic modulus is calculated by the following formula using the "slope of the tangent at the maximum load of the unloading curve (tangent stiffness S=dP / dh)" and the "area of ​​contact between the indenter and the measurement sample (contact projected area B)". The indentation depth of the indenter is 5 μm. The slope of the tangent to the unloading curve at maximum load is calculated by the following method. It is assumed that the power law of the following formula (1) holds for the unloading curve. In formula (1), A, hf, and m are constants determined by applying the least squares method to the unloading curve. Formula (1) is differentiated to obtain formula (2). The slope of the tangent to the unloading curve at maximum load is calculated from formula (2). Note that A, hf, and m are calculated by applying the least squares method to the unloading curve between 20% and 95% of the indenter pressing load on the unloading curve.

number

number

number

[0037] The slope of the load curve when the member 30 is measured by the nanoindentation method is preferably 1 [μN / nm] or more and 5 [μN / nm] or less. The slope of the load curve is calculated based on the results of the measurement in the same manner as the measurement of the hardness of the member 30. The slope of the load curve when the indenter's indentation depth is between 50% and 85% is adopted. In the above measurement, since the indenter's indentation depth is 5 μm, the slope of the load curve when the displacement is between 2.5 μm and 4.25 μm is adopted.

[0038] In order to increase the hardness, elastic modulus, and slope of the load curve of the member 30 measured by the nanoindentation method, for example, a resin material with a higher elastic modulus is blended into the member 30 in a larger amount. On the other hand, in order to decrease the hardness, elastic modulus, and slope of the load curve of the member 30, for example, a plasticizer or a resin material with a lower elastic modulus is blended into the member 30 in a larger amount.

[0039] The minimum load of the load curve when the above member 30 is measured by the nanoindentation method is preferably -0.40 μN or more and 0 μN or less, and more preferably -0.10 μN or more and 0 μN or less. When the minimum load of the load curve is -0.10 μN or more and 0 μN or less, the wettability of the above member 30 is almost eliminated, and better slip properties are exhibited. The minimum load of the unloading curve when the member 30 is measured by the nanoindentation method is preferably -1.50 μN or more and 0 μN or less, and more preferably -0.10 μN or more and 0 μN or less. When the minimum load of the unloading curve is -0.10 μN or more and 0 μN or less, the adhesive force (adhesive force) of the member 30 is almost eliminated, and better slip properties are exhibited. In order to increase the minimum load of the above-mentioned load curve and the minimum load of the unload curve by the nanoindentation method, for example, a hard material with poor adhesion is blended into the member 30. On the other hand, in order to decrease the minimum load of the above-mentioned load curve and the minimum load of the unload curve, for example, a soft material with good adhesion is blended into the member 30.

[0040] The convex portion component 30 is made of a material having the above-mentioned hardness. The convex portion component 30 is made of a resin containing at least a resin material, for example. As such a resin material, for example, one or more of the following are used: polyolefin resins such as polyethylene (PE), polypropylene (PP), and ethylene-propylene copolymers; ethylene-vinyl acetate copolymer resins (EVA); styrene-based thermoplastic elastomer resins (styrene-based block copolymers) such as SIS and SEBS; acrylic resins; polyvinyl chloride resins, CEBC resins; polyesters such as PET; polyurethane resins; polyimide resins; polyamide resins; and polycarbonate resins. The convex portion component 30 is not particularly limited, but is preferably formed of a material containing one or more resins selected from the group consisting of polyolefin resins, polyester resins, ethylene-vinyl acetate copolymer resins (EVA), styrene-based thermoplastic elastomer resins such as SIS and SEBS; polyolefin-based elastomer resins; polyurethane-based elastomer resins; acrylic-based elastomer resins; acrylic resins; and polyamide resins as the main component. The convex portion constituent member 30 preferably contains any one of these resins in an amount of more than 10 mass %.The convex portion constituent member 30 preferably contains the above resin material in an amount of 30 mass % or more. Among the above resin materials, at least one selected from the group consisting of polyolefin resin, ethylene-vinyl acetate copolymer resin (EVA), the above-mentioned styrene-based thermoplastic elastomer resin, acrylic resin, and polyamide resin is preferred. In other words, the convex portion component 30 preferably contains at least one selected from the group consisting of polyolefin, ethylene-vinyl acetate copolymer resin (EVA), the above-mentioned styrene-based thermoplastic elastomer resin, acrylic resin, and polyamide resin. It is particularly preferred that the convex portion component 30 contains at least one resin selected from the group consisting of polyolefin resin, ethylene-vinyl acetate copolymer resin (EVA), the above-mentioned styrene-based thermoplastic elastomer resin, and acrylic resin. By including the preferable resin material as described above in the convex portion constituent member 30, damage to the surface of the object to be cleaned due to sliding contact is suppressed. In addition, by including the preferable resin material as described above in the convex portion constituent member 30, good slipperiness and good durability (strength) can be more fully exhibited.

[0041] The convex portion constituent member 30 may contain at least one of wax, hardened resin, and inorganic powder in addition to the above resin material in order to have a higher elastic modulus. It is particularly preferable that the convex portion constituent member 30 contains wax in order to have better slipperiness. It is preferable that the convex portion constituent member 30 contains an extender pigment as inorganic powder. By the convex portion constituent member 30 containing wax and an extender pigment as inorganic powder in addition to a resin material, the slipperiness of the convex portion constituent member 30 itself is improved, the frictional force of the convex portion constituent member 30 itself is reduced, and the slipperiness of the cleaning sheet 1 is significantly improved.

[0042] Wax (solid wax) is a substance that is solid at room temperature (20°C) but changes to a paste or liquid state at a temperature higher than the melting point of the wax (for example, a temperature 2 to 3 degrees higher than the melting point). The melting point can be measured using a commercially available melting point measuring device or a differential scanning calorimeter (DSC). The melting point of the wax is usually 50° C. or higher and 130° C. or lower, and preferably 80° C. or higher. Since wax is hard at room temperature, the convex component 30 containing wax has a relatively high hardness or elastic modulus at room temperature. In contrast, at a temperature slightly higher than the melting point of the wax, the wax rapidly melts and becomes less viscous than the resin material. Therefore, the wax-containing convex component 30 has good processability in hot melt coating. In addition, the convex component 30 containing wax in addition to the resin material has the advantage of being easily cut because the stretchability caused by the resin material is suppressed. Therefore, the cleaning sheet 1 can have tape-cutting properties.

[0043] The hardness of the wax, expressed in terms of the penetration index, is usually 0.1 or more and 60 or less. The penetration index of the wax is preferably 50 or less, more preferably 35 or less, even more preferably 30 or less, still more preferably 15 or less, and particularly preferably 10 or less. The penetration index of the wax may be 1 or more. The above penetration value is a value measured according to the Japanese Industrial Standards (JIS K2235 2009 5.4 Penetration Test Method). The measurement conditions are a temperature of 25°C, a load of 100g, and a time of 5 seconds.

[0044] Examples of the wax include hydrocarbon waxes and non-hydrocarbon waxes. Examples of hydrocarbon waxes that can be used include petroleum mineral waxes such as paraffin wax, ceresin wax, and microcrystalline wax, as well as synthetic waxes such as polyethylene wax (low molecular weight polyethylene), polypropylene wax (low molecular weight polypropylene), and Fischer-Tropsch wax. Examples of non-hydrocarbon waxes that can be used include natural waxes such as castor wax, carnauba wax, Japan wax, Japanese laurel wax, beeswax, montan wax, candelilla wax, and rice wax, and synthetic waxes such as diheptadecyl ketone, dipentadecyl ketone, diundecyl ketone, and ditridecyl ketone. The wax is preferably a hydrocarbon wax.

[0045] Specific examples of commercially available waxes are listed below. Examples of waxes that can be used include microcrystalline waxes manufactured by Nippon Seiro Co., Ltd., such as trade names Hi-Mic-1045 (melting point 72°C, penetration 37), Hi-Mic-1070 (melting point 80°C, penetration 20), Hi-Mic-2095 (melting point 101°C, penetration 8), Hi-Mic-1090 (melting point 88°C, penetration 6), and Hi-Mic-1080 (melting point 84°C, penetration 12). Further examples include Fischer-Tropsch waxes manufactured by Nippon Seiro Co., Ltd., such as trade names FT115 (melting point 113°C, penetration 1), SX105 (melting point 102°C, penetration 1), FT-0165 (melting point 73°C, penetration 5), and FT-0070 (melting point 72°C, penetration 11). Further examples of waxes include Fischer-Tropsch wax manufactured by Sasol, trade names being Sasolwax H1 (melting point 112°C, penetration 1) and Sasolwax C80 (melting point 88°C, penetration 4 to 9). Further examples include low molecular weight polyolefin waxes manufactured by Sanyo Chemical Industries, Ltd., such as trade names Sanwax 171-P (penetration degree 5), Sanwax 151-P (penetration degree 4), Sanwax 131-P (penetration degree 4), Sanwax 161-P (penetration degree 2), Sanwax E-310 (penetration degree 5), Sanwax E-330 (penetration degree 4) and Sanwax E-250P (penetration degree 5). Other examples include polyethylene wax manufactured by Yasuhara Chemical Co., Ltd. under the trade name Neowax (melting point 110°C, penetration 5); polyethylene wax manufactured by Mitsui Chemicals, Inc. under the trade names Hiwax HP10A (melting point 116°C, penetration 2), Hiwax 210P (melting point 114°C, penetration 4), Hiwax 210MP (melting point 112°C, penetration 3), Hiwax 4202E (melting point 100°C, penetration 5), Hiwax NL100 (melting point 103°C, penetration 3), and Hiwax NP056 (melting point 124°C, penetration 2).

[0046] The convex portion constituent member 30 preferably contains 5 parts by mass or more of wax per 100 parts by mass of the resin material, more preferably 10 parts by mass or more, even more preferably 50 parts by mass or more, and particularly preferably 100 parts by mass or more. Also, the convex portion constituent member 30 may contain 300 parts by mass or less of wax per 100 parts by mass of the resin material, may contain 250 parts by mass or less, or may contain 200 parts by mass or less. The convex portion constituent member 30 may contain only wax.

[0047] The convex component 30 preferably contains 1 part by mass or more of the inorganic powder relative to 100 parts by mass of the resin material, more preferably 5 parts by mass or more, even more preferably 50 parts by mass or more, and particularly preferably 100 parts by mass or more. Also, the convex component 30 may contain 400 parts by mass or less, 250 parts by mass or less, or 200 parts by mass or less of the inorganic powder relative to 100 parts by mass of the resin material. Examples of the inorganic powder include an extender pigment, a color pigment, a functional particle, etc. Examples of the extender pigment include silica, titanium oxide, zinc oxide, magnesium carbonate, calcium carbonate, talc, etc. The convex portion constituent member 30 may contain an organic pigment or an organic dye in addition to the inorganic powder.

[0048] When the component 30 of the convex portion contains the above-mentioned resin material, the above-mentioned extender pigment (inorganic powder), and the above-mentioned wax, the component 30 may contain 1 part by mass or more and 300 parts by mass or less of the extender pigment per 100 parts by mass of the above-mentioned resin material, and may contain 1 part by mass or more and 300 parts by mass or less of the wax per 100 parts by mass of the above-mentioned resin material.

[0049] The convex component 30 may contain a cured resin (cured resin). An example of the cured resin is an uncured resin that is cured by energy rays such as ultraviolet rays or electron beams. Specific examples of the cured resin include cured ultraviolet-curable (UV-curable) resin and cured electron-beam-curable (EB-curable) resin. The cured resin may be a two-liquid reactive crosslinking type cured product. For example, a convex component 30 having sufficient hardness and elasticity can be produced by coating a composition for the convex component 30 containing a UV-curable resin and curing the composition by UV irradiation. This also makes it possible to obtain a cleaning sheet 1 with good slipperiness.

[0050] The convex portion constituent member 30 preferably contains 10 parts by mass or more, more preferably 50 parts by mass or more, of the cured resin relative to 100 parts by mass of the resin material (thermoplastic resin). Also, the convex portion constituent member 30 may contain 400 parts by mass or less, or 200 parts by mass or less, of the cured resin relative to 100 parts by mass of the resin material. The convex portion constituent member 30 may contain only the cured resin.

[0051] The cleaning sheet 1 of this embodiment may contain a fiber aggregate, generally called a woven fabric or nonwoven fabric, in the convex component 30 or the adhesive layer 40. In other words, the convex component 30 and the adhesive layer 40 may be at least partially composed of a fiber aggregate. The fiber aggregate generally refers to an aggregate of fibers with a diameter of less than 0.03 mm. The fiber aggregate is produced, for example, by a melt-blowing method.

[0052] The basis weight (grammage) of the component 30 of the protrusion, in other words, the mass of the component 30 per unit area of ​​the cleaning surface 10, is appropriately set in consideration of the slipperiness, etc. Such basis weight is preferably 5 g / m 2 More preferably, it is 10 g / m 2 More preferably, 20 g / m 2 More preferably, it is 30 g / m 2 More preferably, 40 g / m 2 More than 50 g / m 2 That is all. If the material of the component 30 of the protrusions is the same and the arrangement of the multiple linear members is the same, then as the basis weight increases, the protruding height of the protrusions 12 increases or the exposed rate of the adhesive layer 40 decreases. Therefore, a larger basis weight can reduce the average adhesive force over the entire cleaning surface 10. This makes it easier to achieve better slipperiness. On the other hand, the above basis weight is preferably 500 g / m2 in order to achieve better dust capture. 2 More preferably, it is 400 g / m or less. 2 More preferably, 300 g / m or less 2 Less than 200 g / m 2 The following is the result.

[0053] The average protruding height of the protrusions 12 (average protruding height H) is set taking into consideration at least the ability to capture dirt. The average protruding height of the protrusions 12 (average protruding height H) is appropriately set taking into consideration slipperiness and durability as well. The average protruding height of the protrusions 12 is the average of the heights from the tips of the protrusions 12 to the adhesive recesses 14. The average protruding height of the protrusions 12 (H: mm) is measured by observing the cross section with a surface roughness meter or a microscope. The average protruding height (average protruding height H) of the protrusions 12 is preferably 1000×10 -3 mm or less, and more preferably 500×10 -3 The average protrusion height (average protrusion height H) is 300×10 -3 mm or less, and 200 × 10 -3 It may be less than mm. The average protruding height (average protruding height H) of the protrusions 12 is 30×10 -3 mm or more, and may be 50 × 10 -3 mm or more, and may be 70 × 10 -3 The average protrusion height (average protrusion height H) may be 100×10 -3 mm or more, and may be 300 × 10 -3 It may be more than mm. By setting the average protruding height (average protruding height H) of the protrusions 12 within the above-mentioned preferred range, the frictional force during sliding contact is suppressed, the slipperiness is improved, and the cleaning surface 10 can be slid more smoothly against the surface of the object to be cleaned. In addition, since the exposed surface of the adhesive layer 40 is positioned recessed from the tip of the protrusion by the above-mentioned numerical value or more, unintended sticking of the cleaning surface 10 to the object to be cleaned can be further suppressed. For example, when the supporting substrate 50 is made of paper with low cushioning properties, or when it is made of nonwoven fabric or foam with high cushioning properties, an appropriate average protruding height of the convex portions 12 can be set.

[0054] The tip of the protrusion 12 preferably has a tapered shape, and more preferably has a rounded shape. In other words, the tip preferably has a shape in which the cross-sectional area in the surface direction of the cleaning surface 10 decreases toward the tip. When the tip has a tapered shape, the tip does not have to be sharp, and may be flat. By tapering the tip of the protrusion 12, it is possible to reduce the frictional force when the protrusion 12 slides against the object to be cleaned, thereby achieving better sliding properties.

[0055] (Adhesive recess) In this embodiment, the adhesive recess 14 is a part of the adhesive layer 40 described below. In other words, a part of the adhesive layer 40 constitutes the adhesive recess 14. In further other words, a part of the surface of the adhesive layer 40 is exposed to constitute the adhesive recess 14. By disposing the linear members of the member 30 on the surface of the adhesive layer 40 with a distance A therebetween, a part of the surface of the adhesive layer 40 is exposed at the distance A, and the remaining part of the surface of the adhesive layer 40 is covered by the member 30. Note that, as described later, the cleaning sheet of the present invention is not limited to such a configuration.

[0056] In this embodiment, as shown in Fig. 1, the adhesive layer 40 extends continuously in the planar direction of the cleaning surface 10. The shape of each adhesive recess 14 when the cleaning surface 10 is viewed in the thickness direction of the cleaning sheet 1 is not particularly limited. The adhesive recess 14 does not have to have a fixed shape. On the other hand, the shape of each adhesive recess may be a polygon such as a square or a triangle, a circle such as a perfect circle or an ellipse, or any other irregular shape.

[0057] The ratio of the exposed area of ​​the adhesive layer 40 on the cleaning surface 10 (hereinafter also simply referred to as the exposure rate) is 30% or more. Such an exposure rate is preferably 40% or more, more preferably greater than 50%, and even more preferably 60% or more. When the exposure rate is greater than 40%, dirt can be more sufficiently captured by the adhesive recesses 14. Therefore, the cleaning sheet 1 having good slip properties can also have good dirt capturing properties. The above-mentioned exposure rate may be 95% or less, or may be 90% or less. By setting the upper limit of the exposure rate to 95% or less, better slip properties can be exhibited. The above-mentioned exposure rate is preferably larger in that clogging due to dirt can be more effectively prevented and dirt can be more adequately captured. However, as described in the above-mentioned Patent Document 1, as the exposure rate increases, the adhesive layer 40 is more likely to come into contact with the object to be cleaned. This can cause glue residue or make cleaning difficult. The above-mentioned cleaning sheet 1 can have good slip properties even when the exposure rate is 30% or more by selecting the material of the convex component 30 or setting the ratio (H / L) described later. For example, the cleaning sheet 1 can be manufactured in a state in which the supporting substrate 50 and the constituent members 30 of the protrusions are directly overlapped by bonding the supporting substrate 50 and the constituent members 30 of the protrusions together, or by coating (described later) the supporting substrate 50 with the constituent members 30 of the protrusions. When manufacturing the cleaning sheet 1 by a coating method, the above-mentioned exposure rate can be appropriately set depending on the material of the constituent members 30 of the protrusions and the member thickness in the thickness direction of the supporting substrate 50, so as to obtain good slip properties and dirt capture properties. In the manufacturing method of punching a fiber sheet to form circular holes and attaching an adhesive sheet to the fiber sheet as in the above-mentioned Patent Document 1, the strength of the fiber sheet is relatively low, so that the size and number of holes are limited, and the exposure rate may be limited. On the other hand, by preparing the convex component 30 by coating, the convex component 30 can be directly formed on the support substrate 50 or the adhesive layer 40, so that the exposure rate can be freely set. In addition, by preparing the convex component 30 by coating, it is possible to easily prepare the convex component 30 having holes and having a shape other than a continuous pattern shape as in Patent Document 1. For example, it is possible to easily form the convex component 30 having any discontinuous pattern shape.

[0058] The exposure rate is the ratio of the total exposed area of ​​the adhesive layer 40 to the total area of ​​the cleaning surface 10. The total area of ​​the cleaning surface 10 is the larger of the area of ​​the portion where the component 30 of the convex portion extends in the surface direction or the area of ​​the adhesive layer 40. When the area of ​​the adhesive layer 40 is used as the total area of ​​the cleaning surface 10, even if the adhesive layer 40 does not extend continuously in the surface direction, the area of ​​the adhesive layer 40 is defined as the area of ​​the region inside from the adhesive composition arranged at the outermost side in the surface direction. The exposure rate can be calculated from the total exposed area of ​​the adhesive layer 40 per unit area of ​​the cleaning surface 10. The exposure rate can be calculated, for example, as follows. Specifically, a photograph of the appearance of the member 30 is taken, the photograph is enlarged on copy paper or the like, and the exposed shape of the adhesive layer 40 is cut out with scissors or the like. Then, the mass of the paper cut out in the unit area is divided by the mass of the paper per unit area to accurately calculate the exposure rate. Also, an accurate exposure rate can be calculated by image processing from an image taken with a microscope or the like. In the examples described later, the exposure rate is measured by these methods. In measuring the exposure rate, the range of the cleaning surface 10 to be measured is preferably the entire range, but if the arrangement pattern of the members is regular, it may be an arbitrarily selected square area, for example, 3 cm x 3 cm. If the arrangement pattern of the members on the cleaning surface 10 is not regular and differs partially, the exposure rate of the entire cleaning surface 10 is measured. In addition, if the supporting substrate 50 is exposed on the cleaning surface 10, the area of ​​the exposed portion of the supporting substrate 50 is not included in the total exposed area of ​​the adhesive layer 40 when calculating the exposure rate. For example, if the supporting substrate 50 and the adhesive layer 40 are exposed between a plurality of linear members of the component 30 of the convex portion, only the area of ​​the exposed portion of the adhesive layer 40 is included in the total exposed area of ​​the adhesive layer 40, and the area of ​​the exposed portion of the supporting substrate 50 is not included in the total exposed area of ​​the adhesive layer 40.

[0059] There is usually a first direction in which the average length of the above-mentioned intervals is minimum in the surface direction of the cleaning surface 10. For example, in this embodiment, the first direction is a direction perpendicular to the extension direction of the linear members of the components 30 of the convex portion. The average length (L: mm) of the shape of the adhesive recesses 14 at the interval A formed by the convex component 30 in the first direction, in other words, the average length (L: mm) of the shape of each adhesive recess 14 in the first direction of the cleaning surface 10, is appropriately set in consideration of the slipperiness and dirt trapping properties. For example, the average length of the shape of the adhesive recesses 14 is preferably 10 mm or less, more preferably 8 mm or less, even more preferably 5 mm or less, and particularly preferably 3 mm or less, in terms of exhibiting better slipperiness. By having the average length of the shape of the adhesive recesses 14 be 10 mm or less, the average adhesive force on the entire cleaning surface 10 becomes smaller, so that it is possible to prevent the unused cleaning sheet from sticking to the packaging material or other cleaning sheets. In addition, the average length of the shape of the adhesive recesses 14 is preferably 0.3 mm or more, more preferably 0.5 mm or more, even more preferably 0.8 mm or more, and particularly preferably 1.0 mm or more, in terms of exhibiting better dirt trapping properties.

[0060] The average length of the shape of the adhesive recesses 14 in the first direction is measured as follows: In principle, a virtual line for determining the first direction is set so as to pass through the center of the cleaning surface where the adhesive recesses are present. In this embodiment, as shown in Fig. 1, a plurality of linear members extend in parallel toward one direction in the surface direction of the cleaning surface 10. Since the average length of the above-mentioned interval is smallest in the direction in which the virtual straight line is perpendicular to the linear members, the first direction is the direction perpendicular to the linear members (see the linear dashed line in Fig. 1). In this embodiment, as shown in Fig. 1, the component member 30 of the convex portion is composed of a plurality of linear members arranged in a straight line at approximately the same interval A in the first direction, and the distance between adjacent linear members is measured at at least 10 points, and the above-mentioned average length is obtained by averaging the measured values. Measurements are also performed in the same manner in the examples described below. When the shape of each adhesive recess 14 is circular as shown in FIG. 4, or when the shape of each adhesive recess 14 is rectangular as shown in FIG. 5, the first direction is determined in the same manner as described above, and the average length of the shape of the adhesive recess 14 is calculated. On the other hand, when it is difficult to determine the first direction as one direction, the average length can be obtained as follows. For example, in one example of the convex part component 30, as shown in FIG. 6, short line members are intermittently arranged at intervals in the longitudinal direction, and the short line members are arranged at approximately the same intervals in the direction perpendicular to the longitudinal direction. Another example of the convex part component 30 is composed of small members that draw letters, as shown in FIG. 7. In such a case, the diameter of the imaginary maximum circle (perfect circle) inscribed in the members in the gap between the members is regarded as the length of the shape of each adhesive recess 14 (see the circle drawn by the dashed line). At this time, at least three arbitrarily selected 3 cm x 3 cm square parts are selected, and the lengths of the shapes of the adhesive recesses 14 at least at 10 points in each square part are measured, and the average values ​​are averaged to obtain the average length.

[0061] In the cleaning surface 10, the ratio (H / L) of the average convex height (H: mm) from the tip of the convex portion 12 to the adhesive concave portion 14 to the average length (L: mm) of the shape of the adhesive concave portion in the first direction in which the average length of the above-mentioned interval in the surface direction of the cleaning surface is the smallest is 15×10 -3 Such a ratio (H / L) is preferably 20×10 -3 More preferably, 25×10 -3 More preferably, 30×10 -3 More preferably, 40×10 -3 More preferably, 45×10 -3 The above ratio (H / L) may be as high as 60×10 -3 It may be 70 x 10 or more. -3 It may be more than that. The above ratio (H / L) is 20 x 10 -3 As a result, the average height of the adhesive recesses 14 relative to the average length of the shape of each adhesive recess 14 is relatively large, so that the adhesive recesses 14 are more prevented from contacting the surface of the object to be cleaned. Therefore, the frictional force on the entire cleaning surface 10 is smaller, and better slipperiness is exhibited. Also, as described above, unintended sticking of the cleaning surface 10 to the object to be cleaned can be more effectively prevented. The above ratio (H / L) is preferably 600×10 -3 Less than or equal to 300×10 -3 Less than 150×10, more preferably -3 Below, particularly preferably 100×10 -3 More preferably, 80×10 -3 The following is the result. The above ratio (H / L) is 600 x 10 -3 By making the thickness of the cleaning surface 10 or less, the adhesive force on the cleaning surface 10 is more easily exerted, and better dust trapping properties are exhibited.

[0062] (Adhesive layer) In this embodiment, the adhesive layer 40 extends in the planar direction of the cleaning surface 10 and is disposed on the rear surface side of the convex portion constituent member 30. The adhesive layer 40 is formed in a layer shape using, for example, an adhesive composition. The cleaning sheet 1 of this embodiment can be produced relatively easily because the cleaning surface 10 can be formed by simply arranging the convex component 30 on the surface of the adhesive layer 40 . Furthermore, when the cleaning surface 10 of the cleaning sheet 1 is used to clean an object to be cleaned, if the tips of the protrusions 12 are pressed against and rub against the surface of the object to be cleaned, the protrusions 12 may penetrate slightly into the adhesive layer 40 while being supported by the adhesive layer 40. This causes the protruding height (protrusion height) of the protrusions 12 to become slightly lower, and the adhesive recesses 14, which are recessed further than the protrusions 12, may come slightly closer to the surface of the object to be cleaned. The closer the adhesive recesses 14 are to the surface of the object to be cleaned, the more reliably the adhesive recesses 14 can capture dirt.

[0063] The adhesive composition forming the adhesive layer 40 includes adhesives such as acrylic adhesives, rubber adhesives, polyester adhesives, urethane adhesives, polyether adhesives, and silicone adhesives. The adhesive composition may further include a tackifier resin and a plasticizer such as process oil. The type and mixing ratio of each component are set according to the application of the cleaning sheet 1 so as to obtain the desired adhesive performance. For example, a rubber-based adhesive is an adhesive that contains a rubber-based polymer as a base polymer. The same applies to other adhesives. The base polymer of the adhesive is the polymer component with the highest content in the adhesive. The adhesive may contain 50% by mass or more, 70% by mass or more, or 90% by mass or more of the base polymer on a solid content basis. The adhesive may contain only the base polymer, for example, 99% by mass or less of the base polymer. In terms of exhibiting better adhesive performance and having a relatively high ratio of performance to raw material cost, the adhesive is preferably a rubber-based adhesive or an acrylic-based adhesive.

[0064] The acrylic adhesive contains an acrylic polymer as a base polymer. The acrylic polymer refers to a polymer whose main monomer component is an acrylic monomer. The acrylic monomer is a monomer having at least one (meth)acryloyl group in one molecule. The main monomer component is a component that occupies 50% by mass or more of the total amount of the monomer components constituting the acrylic polymer. 70% by mass or more of the monomer components constituting the acrylic polymer may be acrylic monomers, or 90% by mass or more of the monomer components constituting the acrylic polymer may be acrylic monomers. The acrylic polymer may be a homopolymer obtained by radical polymerization, or a copolymer obtained by random copolymerization. The acrylic polymer may be a thermoplastic (typically hot melt type) block copolymer. In this specification, the (meth)acryloyl group refers collectively to an acryloyl group and a methacryloyl group. Similarly, in this specification, the (meth)acrylate refers collectively to an acrylate and a methacrylate.

[0065] Examples of rubber-based adhesives include adhesives that contain, as a base polymer, one or more of the following rubber-based polymers: natural rubber polymers such as natural rubber and modified rubbers, isoprene rubber, chloroprene rubber, styrene-isoprene-styrene block copolymer (SIS), styrene-butadiene-styrene block copolymer (SBS), styrene-ethylene / butylene-styrene block copolymer (SEBS), crystalline polyolefin-ethylene / butylene-crystalline polyolefin block copolymer (CEBC), and styrene-ethylene / butylene-crystalline polyolefin block copolymer (SEBC). As the rubber-based adhesive, an adhesive containing SIS as a base polymer (SIS-based adhesive) is preferable.

[0066] Examples of the tackifier resin include various tackifier resins such as general rosin-based, terpene-based, hydrocarbon-based, epoxy-based, polyamide-based, elastomer-based, phenol-based, and ketone-based resins. These may be used alone or in appropriate combination of two or more. The amount of the tackifier resin to be blended with respect to 100 parts by mass of the base polymer is not particularly limited, but may be, for example, 50 parts by mass or more and 200 parts by mass or less, and preferably 80 parts by mass or more and 150 parts by mass or less.

[0067] Examples of the plasticizer include process oils, acrylic oligomers, phthalate ester plasticizers such as dioctyl phthalate, diisononyl phthalate, diisodecyl phthalate, and dibutyl phthalate, adipate ester plasticizers such as dioctyl adipate and diisononyl adipate, trimellitic acid esters such as trioctyl trimellitate, sebacic acid esters, epoxidized vegetable oils such as epoxidized soybean oil and epoxidized linseed oil, epoxidized fatty acid alkyl esters such as epoxidized fatty acid octyl esters, cyclic fatty acid esters and derivatives thereof such as sorbitan monolaurate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, and ethylene oxide adducts thereof. As the plasticizer, one of these can be used alone or two or more can be used in appropriate combination. In the pressure-sensitive adhesive composition, the amount of plasticizer to be blended per 100 parts by mass of the base polymer is not particularly limited, but may be, for example, 50 parts by mass or more and 200 parts by mass or less, and preferably 90 parts by mass or more and 150 parts by mass or less. Examples of the process oil include general paraffin-based, naphthenic, and aromatic process oils.

[0068] The pressure-sensitive adhesive composition (e.g., a composition containing a SIS-based pressure-sensitive adhesive) may further contain various additives such as antiaging agents, antioxidants, UV absorbers, light stabilizers, antistatic agents, lubricants, colorants (pigments, dyes, etc.), etc. The types and amounts of these additives may be the same as those typically used in the field of general pressure-sensitive adhesives.

[0069] Various types of adhesive compositions are used to prepare the adhesive layer 40. For example, a hot melt type composition that is heated and melted, then cooled and solidified to form the adhesive layer 40, a curing type composition containing a curing agent as necessary, an energy ray radiation curing type composition that is cured by irradiation with energy rays such as ultraviolet rays (UV) and electron beams (EB), a water dispersion type (typically an emulsion type) type composition in which the adhesive component is dispersed in water, a solvent type composition in which the adhesive component is dissolved in an organic solvent, etc. are used. From the viewpoint of good productivity and reduction of environmental load, a hot melt type adhesive composition is preferably used to prepare the adhesive layer 40.

[0070] The probe tack of the adhesive layer 40 measured by the probe tack method is 1.0 kN / m 2 More than 500.0kN / m 2 It is preferable that: The probe tack of the adhesive layer 40 is 1.0 kN / m 2 More than 500.0kN / m 2 In addition, since the hardness of the component 30 of the protrusion is 0.4 MPa or more as described above, it is possible to achieve good slipperiness and good dust capture properties.

[0071] The probe tack of the adhesive layer 40 measured by the probe tack method is 250.0 kN / m 2 More preferably, it is 150.0 kN / m or less. 2 It is even more preferable that: The probe tack of the adhesive layer 40 is 250.0 kN / m 2 By satisfying the above condition, even if the adhesive recesses 14 come into contact with the surface of the object to be cleaned, the cleaning surface 10 moves along the surface of the object to be cleaned in sliding contact, so that the adhesive recesses 14 can be relatively easily separated from the surface of the object to be cleaned. Therefore, the cleaning surface 10 slides better against the surface of the object to be cleaned. Therefore, the above-mentioned cleaning sheet 1 has better slipperiness. The measured probe tack of the adhesive layer 40 was 5.0 kN / m 2 or more, 10.0 kN / m 2 or more, 25.0 kN / m 2 or more, 50.0 kN / m 2 It may be more than that. In order to increase the measured probe tack value of the adhesive layer 40, for example, an appropriate amount of a tackifier resin or plasticizer is blended into the adhesive layer 40. On the other hand, in order to decrease the measured probe tack value of the adhesive layer 40, for example, the content of the tackifier resin or plasticizer in the adhesive layer 40 is reduced.

[0072] The probe tack of the adhesive layer 40 is measured by a probe tack tester. At least 10 measurements are performed, and the average of the measured values ​​is taken as the probe tack value. The detailed test conditions are as follows: a circular stainless steel probe (diameter: 5 mm) is brought into contact with the adhesive surface of the adhesive layer 40 for 1 second while applying a constant load (50 gf / 5 mmφ), and then the force required to pull the probe 5 mm away from the adhesive surface in the vertical direction is calculated, and this is taken as the probe tack (adhesive strength) value of the adhesive layer. The measurement is performed with the adhesive layer 40 overlapping the support substrate 50. The contact speed (pressing speed) of the probe is 120 mm / min, and the peeling speed is 600 mm / min. The measurement is performed in an environment of 23°C and 50% RH.

[0073] The adhesive strength of the adhesive layer 40 is appropriately set, taking into consideration the slipperiness and dirt trapping ability of the cleaning sheet 1. The adhesive strength of the adhesive layer 40 is measured by peel strength as described below. The 180-degree peel strength of the adhesive layer 40 is preferably 0.5 N / 25 mm or more, more preferably 1.0 N / 25 mm or more, even more preferably 3.0 N / 25 mm or more, and particularly preferably 5.0 N / 25 mm or more, in terms of exhibiting better dirt capture properties. Since household dust and other dirt are relatively light, an adhesive layer 40 having an adhesive strength of 1.0 N / 25 mm or more can capture the dirt sufficiently. In addition, in terms of exhibiting good slip properties on the object to be cleaned and suppressing the cleaning sheet 1 from sticking to the surface of the object to be cleaned, the 180-degree peel strength of the adhesive layer 40 is preferably 40 N / 25 mm or less, more preferably 25 N / 25 mm or less, even more preferably 20 N / 25 mm or less, and particularly preferably 15 N / 25 mm or less. The above 180-degree peel strength is a measured value based on a 180-degree peel test for stainless steel (SUS304) plate specified in JIS Z 0237. When the adhesive layer 40 does not extend in the surface direction of the cleaning surface 10, but is formed, for example, as a plurality of lines extending in one direction in the surface direction (in the case of a discontinuous coating), the 180-degree peel strength of the adhesive layer is obtained by converting the actually measured strength into the strength at a width of 25 mm as described above. In addition, when the adhesive layer 40 is a discontinuous coating as described above, it is difficult to obtain an average value, so the peak value (maximum value) observed in the measurement is used to obtain the 180-degree peel strength.

[0074] Specifically, the measurement of the peel strength is carried out in the following procedure. A sheet-like test piece cut into a rectangular shape is taken out from the adhesive layer 40 supported on the support substrate 50. The length of the test piece is preferably about 100 to 200 mm, and the width is preferably about 15 to 25 mm. If the width of the test piece is less than 25 mm, the conversion value [N / 25 mm] can be calculated (converted) from the ratio of the actual width of the test piece to the reference width of 25 mm. The thickness of the test piece is not particularly limited. One surface (the surface on the cleaning side) of the test piece is attached to a stainless steel (SUS304) plate, and a 2 kg roller is moved back and forth once to press the test piece. If both sides of the test piece are adhesive, it is preferable to line the surface opposite to the surface to be measured with a polyethylene terephthalate (PET) film with a thickness of about 25 μm. The test sample prepared in this way is kept in an environment of 23° C. and RH 50% for 30 minutes. Thereafter, the 180 degree peel strength (adhesive strength to SUS) [N / 25 mm] is measured using a tensile tester in accordance with JIS Z 0237 under conditions of 23°C, 50% RH, a peel angle of 180 degrees, and a pulling speed of 300 mm / min. The tensile tester used is not particularly limited, and a conventionally known tensile tester can be used. For example, "Tensilon" manufactured by Shimadzu Corporation can be used.

[0075] The average thickness of the adhesive layer 40 (when the adhesive layer has a multi-layer structure, the average total thickness of the multiple adhesive layers) can be appropriately set according to the purpose, and is not particularly limited. The average thickness of the adhesive layer 40 is preferably 1 μm or more, more preferably 5 μm or more, even more preferably 10 μm or more, and particularly preferably 15 μm or more, in terms of exhibiting better dirt capture properties. The average thickness of the adhesive layer 40 is preferably 300 μm or less, more preferably 150 μm or less, even more preferably 60 μm or less, and particularly preferably 40 μm or less, in terms of exhibiting better slip properties and preventing glue residue on the object to be cleaned. The average thickness is the average of measurements at least at five randomly selected points.

[0076] (Supporting base material) The above cleaning sheet 1 preferably includes a supporting substrate 50. By including the supporting substrate 50 in the above cleaning sheet 1, the adhesive layer 40 is supported by the supporting substrate 50, and deformation of the adhesive layer 40 during sliding contact can be suppressed. Therefore, the adhesive performance of the adhesive layer 40 is fully exhibited, and better dirt capture properties are exhibited.

[0077] The tensile strength of the support substrate 50 is preferably 5N / 50mm or more. By having the tensile strength of the support substrate 50 be 5N / 50mm or more, the adhesive layer 40 is more fully supported by the support substrate 50. As a result, as described above, the protrusions 12 can penetrate slightly into the adhesive layer 40 while being more fully supported by the adhesive layer 40 during sliding contact. This allows the adhesive recesses 14 to come slightly closer to the surface of the object to be cleaned. And, as the adhesive recesses 14 come closer to the surface of the object to be cleaned, the adhesive recesses 14 can capture dirt more reliably. The strength of the support substrate 50 may be 200N / 50mm or less.

[0078] The tensile strength of the supporting substrate 50 is determined by measuring the tensile strength of the supporting substrate 50. Specifically, the strength (tensile strength) is measured by setting a test piece cut into a strip having a width of 50 mm in a tensile tester (distance between chucks: 100 mm) and measuring the tensile strength [N / 50 mm] at a tension speed of 200 mm / min.

[0079] The support substrate 50 may be various resin sheets, fiber sheets such as nonwoven fabric, woven fabric, and paper, metal foil, or a composite of these. The support substrate 50 preferably has at least one of a resin sheet and a fiber sheet. Resin sheets include synthetic resin films, rubber sheets, and foam sheets. Fiber sheets include nonwoven fabric, woven fabric, and paper. The shape of the support substrate 50 is not particularly limited and may be flat, cylindrical, or the like, and may be a deformable material such as a cloth or sponge. The support substrate 50 may be made of polyolefin, polyester, other synthetic resins, paper, synthetic or natural fibers, or metals such as stainless steel.

[0080] Examples of the material of the resin sheet include polyolefin (PE, PP, ethylene-propylene copolymer, etc.), polyester (PET, etc.), vinyl chloride resin, vinyl acetate resin, polyimide resin, polyamide resin, fluororesin, etc. Examples of the rubber sheet include natural rubber sheet, butyl rubber sheet, etc. Examples of the foam sheet include various foamed resin sheets such as polyethylene, polypropylene, polyurethane, ethylene-vinyl acetate copolymer (EVA), polyethylene terephthalate (PET), etc. Examples of the paper include Japanese paper, craft paper, glassine paper, fine paper, synthetic paper, topcoat paper, etc. Examples of the woven fabric or nonwoven fabric include those formed by a single type of fiber or a blend of multiple types of fibers. Examples of the above-mentioned fiber include cotton, staple fiber, Manila hemp fiber, pulp, rayon fiber, acetate fiber, polyester fiber, polyvinyl alcohol fiber, polyamide fiber, polyolefin fiber, etc. The manufacturing method of the nonwoven fabric may be spunlace, chemical bond, meltblown, steam jet, needle punch, etc. Examples of the metal foil include aluminum foil and copper foil.

[0081] In addition, when a nonwoven fabric or a foam having a large surface roughness (unevenness) is used as the support substrate 50 as it is, the convex portion component 30 and the adhesive layer 40 may not adhere sufficiently even if they are superimposed on the support substrate 50. In response to this, it is preferable to cover the nonwoven fabric or the foam with a polyethylene film or a polypropylene film and provide a smooth laminated layer on the surface layer of the support substrate 50. By smoothing the surface of the surface layer of the support substrate 50 with a laminated layer, it becomes possible to form the convex portion component 30 and the adhesive layer 40 at high speed by coating, which will be described later. This allows the convex portion component 30 and the adhesive layer 40 to be produced relatively quickly and easily.

[0082] The supporting substrate 50 may contain various additives, such as a filler (inorganic filler, organic filler, etc.), an antiaging agent, an antioxidant, an ultraviolet absorber, a light stabilizer, an antistatic agent, a lubricant, a plasticizer, a colorant (pigment, dye, etc.), etc., as necessary.

[0083] The thickness of the support substrate 50 is not particularly limited and can be appropriately selected depending on the purpose. The thickness of the support substrate 50 is preferably 5 μm or more, more preferably 10 μm or more, and even more preferably 20 μm or more. The thickness of the support substrate 50 is preferably 5 mm or less, more preferably 3 mm or less, and particularly preferably 1 mm or less. The cleaning sheet 1 may be a rubber plate as the support substrate 50, and the adhesive layer 40 and the convex component 30 are provided on the support substrate 50. The above thickness is appropriately designed for the support substrate 50 made of, for example, a synthetic resin sheet, a nonwoven fabric, or a paper.

[0084] The cleaning sheet 1 of this embodiment has an uneven cleaning surface, and is used by mainly sliding the tips of the protrusions against the object to be cleaned. Therefore, even if the adhesive concave portions, which have a relatively high adhesive force and are recessed further than the protrusions, do not come into contact with the object to be cleaned, the cleaning surface can move along the surface of the object to be cleaned. Therefore, the frictional force during sliding contact can be made relatively small. Therefore, the above-mentioned cleaning sheet has good sliding properties because it can slide against the surface of the object to be cleaned with a relatively small frictional force. In addition, the ratio (H / L) of the average convex height (H: mm) from the tip of the convex to the adhesive concave portion to the average length (L: mm) of the shape of the adhesive concave portion in the first direction in which the average length of the interval in the surface direction of the cleaning surface is the smallest is 15×10 -3 For the above reasons, the adhesive recesses are prevented from coming into contact with the surface of the object to be cleaned while the tips of the protrusions can slide against the surface. Thus, while the protrusions are in sliding contact with the object to be cleaned, dirt can be collected in the gaps between the members that make up the protrusions. Furthermore, according to the cleaning sheet 1 of this embodiment, dirt can be effectively captured due to the adhesiveness of the adhesive recesses 14. For example, when a cleaning worker wipes, the cleaning sheet 1 slides against the object to be cleaned, and dirt on the object is captured in the adhesive recesses 14 of the cleaning surface 10. The captured dirt is collected in a depression near the adhesive recesses 14. Even if the captured dirt is relatively heavy, the adhesive force of the adhesive recesses 14 allows the dirt to continue to be captured. In the cleaning sheet 1 of this embodiment, the proportion of the exposed area of ​​the adhesive layer on the cleaning surface 10 is 30% or more, so that the cleaning sheet 1 can capture dirt sufficiently. On the other hand, when heavy dirt is captured by a conventional simple fiber assembly, the weight of the captured dirt tends to separate from the fiber assembly. Thus, with the cleaning sheet 1, even relatively heavy dirt such as sand grains, which are relatively difficult to capture, can be retained by the adhesive force of the adhesive recesses 14. Therefore, the cleaning sheet 1 has good dirt capture properties. Thus, the cleaning sheet 1 having the above-mentioned structure has good slip properties and good dirt trapping properties.

[0085] (Any other layers or components) The cleaning sheet 1 of this embodiment may further include one or more layers, as necessary, in addition to the convex portion constituent members 30, the adhesive layer 40, and the supporting substrate 50 described above. For example, in order to impart appropriate thickness, cushioning properties, strength, etc. to the cleaning sheet 1, an intermediate layer may be disposed between the convex component 30 and the adhesive layer 40. The intermediate layer may be a layer having a spacing similar to the spacing A in the convex component 30. The configuration of the intermediate layer is not particularly limited, and may be a resin layer formed from various resin materials, a rubber layer (a natural rubber sheet, a butyl rubber sheet, etc.), a foam layer, a fibrous layer (paper, cloth, woven or nonwoven fabrics made of various fibrous materials alone or in a blend, etc.), or a metal layer (typically a metal foil), etc. An anchor layer may be provided between the adhesive layer 40 and the support substrate 50 to improve anchoring properties. The back surface (non-adhesive layer surface) of the support substrate 50 may be provided with various coating layers for the purpose of imparting design or improving handling properties. In addition, in a cleaning sheet having a cleaning surface formed only on one side, an adhesive layer may be overlapped on the back side (opposite to the cleaning surface) of the support substrate. The adhesive strength of the adhesive layer is higher than that of the component of the convex portion and lower than that of the adhesive layer. The adhesive layer may be formed of ethylene-vinyl acetate copolymer resin (EVA). When a plurality of cleaning sheets having such an adhesive layer are stacked in the same direction in the thickness direction, or when cleaning sheets having an adhesive layer are rolled and stacked, the stacked state is prevented from shifting, and further, the overlapping cleaning sheets can be prevented from strongly sticking to each other. In addition, the convex portion may be formed of a self-adhesive material having self-adhesive properties, and the back surface of the support substrate may be formed of such a self-adhesive material. As the self-adhesive material, a low molecular weight tackifier or chloroprene rubber may be used. The convex portion formed of the self-adhesive material does not have much adhesion unless it comes into contact with other self-adhesive materials, and therefore exhibits slippage. On the other hand, when the self-adhesive material is also used for the back surface of the support substrate of the cleaning sheet, when the cleaning sheets are stacked as described above, the stacked state is prevented from shifting, and the overlapping cleaning sheets are prevented from strongly sticking to each other.

[0086] In addition, in a cleaning sheet having a cleaning surface formed only on one side, a back side member 60 similar to the convex component may be provided on the back side of the support substrate. For example, the back side member 60 is composed of a plurality of linear members as shown in FIG. 8, and these linear members extend in the same direction as the convex component 30 on the front side. When a plurality of cleaning sheets having such a configuration are stacked in the same direction in the thickness direction, or when cleaning sheets having such a configuration are rolled and stacked, the convex parts of the convex component and the convex parts of the back side member 60 can be arranged alternately, so that the stacked state is prevented from shifting. In detail, the convex component 30 of one cleaning sheet can be inserted between the back side member 60 of the other cleaning sheet, and the cleaning sheet can be prevented from shifting in the width direction of the linear members.

[0087] The total thickness of the cleaning sheet 1 of this embodiment is not particularly limited. The total thickness of the cleaning sheet 1 having a sheet shape may be 1800 μm or less, 1000 μm or less, or 800 μm or less. The total thickness of the cleaning sheet 1 is preferably 500 μm or less, more preferably 300 μm or less, and even more preferably 250 μm or less, in terms of improving the handling property and the like. The total thickness may be 50 μm or more, or may be 120 μm or more. The total thickness is preferably 150 μm or more, more preferably 180 μm or more, and even more preferably 200 μm or more, in terms of exhibiting better slipping property and better dirt capture property and the like. Such a total thickness is an average of thicknesses at least five randomly selected points.

[0088] (Manufacturing method of cleaning sheets) The method for producing the cleaning sheet 1 of this embodiment is a method for forming the constituent members 30 of the protrusions by coating.

[0089] In the above manufacturing method, the convex portion constituent members 30 can be formed by coating on the supporting base material 50 . Furthermore, in the above manufacturing method, the convex portion constituent members 30 can be formed by being overlaid on the adhesive layer 40 by coating. When the component 30 of the convex portion is overlaid on the supporting substrate 50 or the adhesive layer 40 by coating, the component 30 may be directly coated on top of the supporting substrate 50 or the adhesive layer 40, or the component 30 of the convex portion may be first coated on another component to form the component 30, and then transferred to the supporting substrate 50 or the adhesive layer 40 (transfer method).

[0090] The method for producing the cleaning sheet 1 of this embodiment includes, for example, an adhesive layer preparation step of preparing an adhesive layer 40 superimposed on the surface of a supporting substrate 50, and a convex portion preparation step of preparing the convex portions 12 by superimposing convex portion components 30 on the surface of the supporting substrate 50 or the adhesive layer 40. The order of these steps is not particularly limited.

[0091] In the adhesive layer preparation step, the adhesive layer 40 can be prepared by a general method. This method is not particularly limited. In the adhesive layer preparation step, the adhesive composition is directly applied to the support substrate 50 by a conventionally known coating means, and then cured or dried. Alternatively, the adhesive composition may be applied to a surface having releasability (for example, the surface of a release liner, or the back surface of a support substrate that has been subjected to a release treatment, etc.), and the applied adhesive composition may be cured or dried to prepare the adhesive layer 40 on the surface. Alternatively, a method (transfer method) may be employed in which the adhesive layer 40 prepared on the surface having releasability is superimposed on the support substrate 50 or the component 30 of the convex portion.

[0092] In the adhesive layer preparation step, the adhesive layer 40 may be prepared over the entire area of ​​one surface of the support substrate 50. On the other hand, for example, the adhesive composition may not be applied to both ends in the width direction of the belt-shaped support substrate 50, thereby providing the support substrate 50 with a non-adhesive portion (dry edge). Typically, a continuous layer-like adhesive layer 40 is prepared, but the adhesive composition may be applied in a regular or random pattern such as a dotted, striped, or lattice pattern depending on the purpose and application. The adhesive layer may be prepared by applying the same adhesive composition or different adhesive compositions multiple times. The coating method used in the adhesive layer forming step may be the same as the coating method used in the convex portion forming step described below.

[0093] In the adhesive layer preparation step, an adhesive composition containing an uncured resin that is cured by energy rays may be applied, and cured by energy rays such as ultraviolet rays or electron beams to prepare the adhesive layer 40. Specific examples of the uncured resin include ultraviolet ray curable (UV curable) resin and electron beam curable (EB curable) resin.

[0094] In the convex portion forming step, the convex portion 12 is formed, for example, by extrusion molding a resin material melted by heating. Specifically, the resin material, which is the raw material of the component 30 of the convex portion, is extruded so as to draw a plurality of parallel lines, and a linear member is formed on the supporting substrate 50 or the adhesive layer 40. Note that the linear member can also be formed by extruding a resin composition containing a resin material, wax, and at least one of the above-mentioned uncured resins in the same manner as above, and irradiating it with energy rays as necessary.

[0095] In the convex portion creating step, various types of compositions are used as the resin composition for creating the convex portion component 30. For example, the above-mentioned hot melt type composition, curing type composition, water dispersion type (typically emulsion type) type composition, solvent type composition, etc. are used. These resin compositions may be directly applied onto the supporting substrate 50, or may be applied onto the adhesive layer 40 overlapping the supporting substrate 50. Any coating method may be used, regardless of whether it is a direct printing method or a transfer method.

[0096] Examples of the coating method include roll coating, gravure coating, flexo coating, kiss coating (including microgravure coating), bar coating, comma coating, blade coating, die coating, slide coating, and curtain coating. As the coating method, die coating, gravure coating, and flexo coating, which are particularly excellent in coating fine patterns, are preferred. In the coating method, the resin composition may be coated so as to form a continuous layer, or the resin composition may be coated so as to form a regular or random non-continuous pattern such as a dot pattern, a stripe pattern, or a lattice pattern, depending on the purpose and application. The adhesive layer 40 and the convex portion component 30 may each have a multi-layer structure of two or more layers. In addition, by foaming and coating the resin composition, the adhesive layer 40 or the convex portion component 30 can have cushioning properties.

[0097] In order to manufacture the cleaning sheet 1 at lower cost, it is also possible to simultaneously coat the adhesive layer 40 and the convex component 30 by employing die coating, slide coating, curtain coating, etc. The coating method for coating each composition for producing the adhesive layer 40 and the convex component 30 may be single-head coating in multi-layer simultaneous coating, or single-pass coating using multiple heads in tandem coating. By preparing the adhesive layer 40 and the convex portion constituent members 30 by a coating method, the cleaning sheet 1 can be manufactured at low cost. Furthermore, when preparing the convex portion constituent members 30 by a coating method, the convex portion constituent members 30 may be a continuous layer that extends in the surface direction of the cleaning sheet 1, or may be a discontinuous layer with a dot pattern or the like. For example, in conventional cleaning sheets that are manufactured by adhering a nonwoven fabric with openings to an adhesive layer, the nonwoven fabric cannot be made into a discontinuous layer. In contrast, in this embodiment, the coating pattern of the convex component 30 can be set so as to improve the slipperiness and dirt capture properties. Therefore, it is possible to arbitrarily set the exposure rate of the adhesive layer to 30% or more, which was not possible with conventional cleaning sheets.

[0098] (Use of cleaning sheets) The cleaning sheet 1 can be used in various places, for example, in places where various kinds of garbage such as dust and debris are present. The cleaning sheet 1 captures garbage by the adhesive force of the adhesive recesses 14 in particular, and maintains the garbage capture, so it is better at capturing relatively heavy garbage such as sand grains, food scraps, and hair than conventional cleaning sheets made of simple fiber aggregates. The cleaning sheet 1 can also be used with good durability not only on indoor flooring, but also on concrete surfaces such as entrance floors and dirt floors where sand grains are present, outdoor balconies, and rough factory floors with large unevenness that have been treated to prevent slipping. The cleaning sheet 1 of this embodiment may be an embodiment that does not include a fiber aggregate, and therefore the cleaning sheet 1 of such an embodiment prevents the generation of fiber waste and paper dust, and is therefore suitable for use in clean rooms, food factories, hospitals, etc.

[0099] The cleaning sheet 1 may be used in a rolled state with the cleaning surface 10 facing outward, and can be used as a new type of adhesive roll cleaner. Conventional adhesive roll cleaners rotate only in the winding direction, so they are used for cleaning by rolling (moving) only in this direction. Therefore, they are not particularly easy to use when cleaning narrow spaces. On the other hand, the above-mentioned new type of adhesive roll cleaner can capture dirt not only by rotating in the winding direction, but also by sliding in a direction other than the rotation direction. Therefore, they are easy to use when cleaning narrow spaces. When the cleaning sheet 1 is wound into a roll as described above, it may come unwound. To address this, an adhesive or adhesive may be provided on all or part of the back side (opposite the cleaning surface) of the cleaning sheet 1. This can prevent the sheet from coming unwound.

[0100] (Laminate) The cleaning sheet 1 may be in a rolled state, or a plurality of cleaning sheets 1 may be stacked in the thickness direction to form a laminate. An example of the laminate is shown in FIG. By fixing the laminate to the sheet fixing part 120, after cleaning work is done on the cleaning surface 10 of the outermost cleaning sheet 1, the cleaning sheet 1 can be removed and a new, unused cleaning sheet 1 can be placed on the outermost side. Therefore, cleaning work can be continued with a new cleaning sheet 1 without replacing the cleaning sheet 1.

[0101] The matters disclosed in this specification include the following. (1) A cleaning sheet having a cleaning surface that is brought into sliding contact with the surface of an object to be cleaned, The cleaning surface has projections and recesses, and is used by bringing tips of the projections into sliding contact with the object to be cleaned; the protrusions are formed of members spaced apart from one another in a surface direction of the cleaning surface, the cleaning surface further has an adhesive recess having a higher adhesive strength than the member and exposed on the cleaning surface; an adhesive layer extending in a surface direction of the cleaning surface and disposed in at least a part of the space between the members, at least a part of the adhesive layer constituting the adhesive recess, and a ratio of an exposed area of ​​the adhesive layer to the cleaning surface being 30% or more; The ratio (H / L) of the average convex height (H: mm) from the tip of the convex portion to the adhesive concave portion to the average length (L: mm) of the shape of the adhesive concave portion in the first direction in which the average length of the interval in the surface direction is the smallest is 15×10 -3 That's it for the cleaning sheet. (2) The cleaning sheet according to (1) above, wherein the proportion of the exposed area of ​​the adhesive layer on the cleaning surface is greater than 50%. (3) The average convex height (H) from the tip of the convex portion to the adhesive concave portion is 1000×10 -3 The cleaning sheet according to (1) or (2) above, wherein the thickness of the cleaning sheet is equal to or less than mm. (4) The average convex height (H) is 500×10 -3 The cleaning sheet according to (3) above, wherein the thickness is less than or equal to 1 mm. (5) The average convex height (H) is 300×10 -3 The cleaning sheet according to (4) above, wherein the thickness is less than or equal to 1 mm. (6) The cleaning sheet according to any one of (1) to (5) above, wherein the average length (L) of the shape of the adhesive recesses in a first direction in which the average length of the intervals in the surface direction is smallest is 0.3 mm or more. (7) The cleaning sheet according to (6) above, wherein the average length (L) is 0.5 mm or more. (8) The cleaning sheet according to (7) above, wherein the average length (L) is 0.8 mm or more. (9) The cleaning sheet according to (8) above, wherein the average length (L) is 1.0 mm or more. (10) The cleaning sheet according to any one of the above (1) to (9), wherein the minimum load of a load curve when the member of the protrusions is measured by a nanoindentation method is −0.40 μN or more and 0 μN or less. (11) The cleaning sheet according to the above (10), wherein the minimum load of a load curve when the member of the protrusions is measured by a nanoindentation method is −0.10 μN or more and 0 μN or less. (12) The cleaning sheet according to any one of (1) to (11) above, wherein the minimum load of an unloading curve when the member of the protrusions is measured by a nanoindentation method is −1.50 μN or more and 0 μN or less. (13) The cleaning sheet according to the above (12), wherein the minimum load of an unloading curve when the member of the protrusions is measured by a nanoindentation method is −0.10 μN or more and 0 μN or less. (14) The cleaning sheet according to any one of (1) to (13) above, wherein the cleaning surface has a static friction coefficient of 1.00 or less. (15) An adhesive layer is provided extending in a surface direction of the cleaning surface and disposed on a rear surface side of the member, and a part of the adhesive layer constitutes the adhesive recess, The hardness of the member measured by a nanoindentation method is 0.4 MPa or more, and the probe tack of the adhesive layer measured by a probe tack method is 1.0 kN / m 2 More than 500.0kN / m 2 The cleaning sheet according to any one of the above (1) to (14), which is: (16) The cleaning sheet according to any one of (1) to (15) above, wherein the member of the protrusions contains at least one of wax, hardened resin, and inorganic powder. (17) The cleaning sheet according to any one of (1) to (16) above, wherein the member of the convex portion contains at least one of polyolefin resin, ethylene-vinyl acetate copolymer resin (EVA), styrene-based thermoplastic elastomer resin, acrylic resin, polyvinyl chloride resin, polyester resin, polyurethane resin, polyimide resin, polyamide resin, and polycarbonate resin. (18) The cleaning sheet according to the above (16), wherein the members of the convex portions contain an extender pigment as the inorganic powder. (19) The cleaning sheet according to (16) above, wherein the wax contained in the member of the protrusions has a penetration hardness of 0.1 or more and 60 or less. (20) The cleaning sheet according to any one of (1) to (19) above, wherein the cleaning surface is formed on both sides. (21) A method for producing the cleaning sheet according to any one of (1) to (20) above, comprising the steps of: The method for producing a cleaning sheet includes forming the members of the protrusions by coating. (22) The cleaning sheet has a supporting substrate, The method for producing a cleaning sheet according to (21) above, wherein the members of the convex portions are formed by coating on the supporting substrate. (23) The cleaning sheet has a support substrate and an adhesive layer overlying the support substrate, The method for producing a cleaning sheet according to (21) above, wherein the members of the convex portions are formed by coating on the adhesive layer. (24) A state in which the cleaning sheet according to any one of (1) to (20) above is rolled up, or A laminate in which a plurality of cleaning sheets according to any one of (1) to (20) above are laminated in the thickness direction. (25) A cleaning sheet according to any one of (1) to (20) above, and a sheet fixing part to which the cleaning sheet is detachably attached.

[0102] The cleaning sheet 1, laminate, and cleaning tool 100 of the above embodiment are as exemplified above, but the present invention is not limited to the above exemplified cleaning sheet, laminate, and cleaning tool. Furthermore, various aspects used in general cleaning sheets and cleaning tools can be adopted as long as they do not impair the effects of the present invention.

[0103] In the cleaning sheet 1 of the above embodiment, the adhesive layer 40 is supported by the supporting substrate 50, but the cleaning sheet of the present invention does not need to have a supporting substrate. For example, the cleaning sheet of the present invention may not have a supporting substrate, and the convex components 30 may be disposed on both sides of the adhesive layer.

[0104] In addition, in the cleaning sheet 1 of the above embodiment, the convex component 30 overlaps the adhesive layer 40, but the cleaning sheet of the present invention is not limited to such an embodiment. For example, as shown in FIG. 2B, the multiple linear members of the convex component 30 may overlap directly on the support substrate 50. In this case, the cleaning surface can be formed by overlapping the linear members of the convex component 30 on the surface of the support substrate 50 such as a resin film or nonwoven fabric with a gap therebetween, and then filling at least a part of the gap with an adhesive composition. In other words, an adhesive layer does not have to be disposed between the support substrate 50 and the convex component 30. For example, the cleaning surface can be formed by forming multiple linear members of the convex component 30 on the support substrate 50 by coating, and coating an adhesive layer between the formed linear members. Thus, in the cleaning sheet of the present invention, the configuration in which the convex component 30 overlaps the surface of the adhesive layer is not essential.

[0105] In addition, in the cleaning sheet 1 of the above embodiment, the exposed area of ​​the adhesive recess 14 (the exposed area of ​​the adhesive layer 40) was approximately the same as the total area of ​​the interval A between the linear members of the component members 30 of the protrusion. However, in the cleaning sheet of the present invention, the exposed area of ​​the adhesive layer 40 may be smaller than the total area of ​​the above interval. For example, the entire recess formed by the above interval may not be occupied by the adhesive composition. A part of the recess may be occupied by a linear (striped) adhesive composition or a dotted (dotted) adhesive composition. In this case, if the supporting substrate is a fiber aggregate, the surface of the fiber aggregate exposed to the cleaning surface can also capture dirt.

[0106] In addition, in the cleaning sheet 1 of the above embodiment, the non-cleaning surface 20 is formed on one side. However, the cleaning sheet of the present invention does not necessarily need to have the non-cleaning surface 20. For example, the cleaning sheet may have a cleaning surface 10 on each side.

[0107] The cleaning sheet 1 of the above embodiment has the convex component 30 in which a plurality of straight line members (linear members) are arranged in parallel, but the cleaning sheet of the present invention is not limited to this. For example, as shown in Fig. 4, the convex component may be a member that is continuous in the planar direction of the cleaning surface 10, and holes (for example, circular or elliptical holes) may be formed in such a member. Further, for example, as shown in FIG. 5, the convex portion may be made of a mesh-like member that is continuous in the planar direction of the cleaning surface 10, and the adhesive layer 40 may be exposed in the mesh. Also, for example, as shown in FIG. 6, multiple short line members may be lined up in the longitudinal direction, and adjacent to each other in a direction perpendicular to the longitudinal direction, with gaps between them in both the longitudinal direction and the perpendicular direction. Also, for example, as shown in FIG. 7, the components of the convex portion may be formed so as to draw a plurality of letters or pictures. The pattern drawn by the convex component 30 may be a regular pattern or an irregular pattern. For example, the pattern drawn by the convex component 30 may be any pattern, such as a dot pattern, a diamond pattern (rhombus shape), a star pattern (starfish shape), etc. The pattern drawn by the convex component 30 may be selected in consideration of the dust capture efficiency, as shown in JP 2011-183153 A, for example.

[0108] In addition, the cleaning tool 100 in the above embodiment has a configuration in which the cleaning sheet 1 is attached to the sheet fixing part 120 at the lower end of the long-handled gripping member 110, but is not limited thereto. The cleaning tool of the present invention may have a short handle (also called a holder) as a gripping member. The cleaning tool of the present invention may have a configuration in which the cleaning sheet is attached to a member (sheet fixing part) having a shape such as a plate-like body, a spherical body, a cylindrical body, or the like, without having such a gripping member. The cleaning tool of the present invention may be a cleaning tool having a soft sheet-like or sponge-like component member such as a cloth. Specifically, the cleaning tool of the present invention may have the above-mentioned cleaning sheet fixed to a part of a soft member, and the desired effect of the present invention can be achieved even with such a configuration. Thus, in the cleaning tool of the present invention, there is no particular limitation on the shapes of the gripping member, the sheet fixing part, the cleaning sheet, etc., and there is no limitation on the materials of each of them. For example, various materials such as polyolefin, polyester, or other synthetic resins, synthetic or natural fibers, and metals such as stainless steel can be used as the constituent materials of the cleaning tool of the present invention.

[0109] Specifically, the cleaning tool 100 of the above embodiment may be a long and thin rod to which the cleaning sheet 1 is attached. This cleaning tool 100 is used as a sliding adhesive type gap cleaning tool. Moreover, the cleaning tool 100 of the above embodiment may be, for example, a slipper with the cleaning sheet 1 attached to the bottom surface. Since the cleaning tool 100 has a convex component, it is used as a product that can clean while walking on the floor without sticking to the floor. In these cleaning tools 100, the attached cleaning sheet 1 may be a single sheet, or may be in the form of a laminate in which a plurality of cleaning sheets are stacked.

[0110] Several examples of the present invention will be described below, but it is not intended that the present invention be limited to these specific examples. EXAMPLES

[0111] Example 1 [Preparation of adhesive (composition)] The following raw materials were mixed to prepare a rubber-based adhesive (SIS-based adhesive composition). Base polymer: styrene-isoprene-styrene block copolymer (SIS) Zeon Corporation product name "Quintac 3520" / 100 parts by weight Tackifier resin: Unhydrogenated hydrocarbon resin Manufactured by ENEOS Product name "T-REZ RC093" / 100 parts by mass Plasticizer: Naphthenic process oil Idemitsu Kosan Co., Ltd. Product name "Diana Process Oil NS90S" / 100 parts by weight [Preparation of Constituent Members for Convex Portions (Composition for Convex Portions)] A composition for the convex portion, Sample 1, was prepared from the following raw materials. Resin material: High density polyethylene resin (HDPE) Braskem product name "SHD7255LSL" / 100 parts by weight Resin material: Ethylene-vinyl acetate copolymer (EVA) Tosoh Corporation Product name "Ultrasen 684" / 200 parts by weight Wax: Hydrocarbon-based Sasol Wax C80, needle penetration 4-9 / 450 parts by weight A protrusion (stripe shape) having a plurality of linear members was formed as shown in Fig. 1. The cleaning sheet was formed to have the schematic shape shown in Fig. 2A.

[0112] [Manufacturing cleaning sheets] A sheet was prepared as a support substrate by laminating one side of a paper sheet with a polyethylene film, and both the adhesive composition and the composition for the protrusions obtained above were hot melt coated (multi-layer simultaneous coating) using a die coater. The adhesive composition was directly coated on the non-laminated side that had not been laminated. The cleaning sheets of the examples described below thus produced have a structure in which the components of the support substrate, adhesive layer, and protrusions are stacked in this order as shown in FIG. 2A , unless otherwise specified. The components of the cleaning sheets in the examples described below are shown in Table 1. Hardness of the convex part (nanoindentation method) [MPa] Elastic modulus of the convex part (nanoindentation method) [MPa] -Slope of the load curve in nanoindentation method [μN / nm] -Minimum load on the load curve in nanoindentation [μN] ·Minimum load on unloading curve in nanoindentation method [μN] Displacement of the unloading curve in nanoindentation [nm] -Static friction coefficient of cleaning surface -Kinematic friction coefficient of cleaning surface Adhesive layer thickness [μm] Probe tack of adhesive layer (kN / m 2 ) - Exposure rate of adhesive layer [%] Average length L of the adhesive recess shape in the first direction [mm] -Spacing between adjacent wire members A [mm] Average convex height H [mm] Ratio of the average height of the convex part (H:mm) to the average length of the adhesive concave part (L:mm) (H / L) Average width of convex part [mm] · Composition of the support substrate

[0113] Hereinafter, cleaning sheets were produced having the configurations shown in Tables 1 to 5. Unless otherwise specified, each cleaning sheet was produced basically in the same manner as in Example 1.

[0114] (Examples 2 to 8, 11) The number of linear members and the average height of the protrusions were changed as shown in Tables 1 and 2, respectively, to produce each cleaning sheet.

[0115] (Reference example 9) In Reference Example 9, a cleaning sheet was produced as follows. [Preparation of adhesive (composition)] Raw material for acrylic adhesives (adhesive compositions) Base polymer: Acrylic triblock copolymer / 100 parts by weight Details of Acrylic Triblock Copolymer *An acrylic block copolymer with a triblock structure of poly[methyl methacrylate (MMA)] block-poly[2-ethylhexyl acrylate (2EHA) / n-butyl acrylate (BA)] block-polyMMA block. *The mass ratio of 2EHA to BA in the poly-2EHA / BA block is 50 / 50, and the mass ratio of the poly-2EHA / BA block to the poly-MMA block (two poly-MMA blocks) [(2EHA+BA) / MMA] is 82 / 18. *Mw is 10 x 10 4 , Mn is 8.4 × 10 4 , Mw / Mn is 1.21 Plasticizer: Acrylic oligomer (liquid) Toagosei Co., Ltd. Product name "ARUFON UP1021" / 30 parts by weight Plasticizer: Adipic acid ester DIC product name "Monocizer W-242" / 30 parts by weight [Preparation of Constituent Members for Convex Portions (Composition for Convex Portions)] A composition for the convex portion, Sample 2, was prepared using only the following raw materials. Resin material: Polyolefin elastomer (glass transition temperature -48°C, melting peak top temperature 47°C)

[0116] (Reference example 10) In Reference Example 10, a cleaning sheet was produced as follows. [Adhesive (composition)] The same as in Reference Example 9 was used. [Preparation of Constituent Members for Convex Portions (Composition for Convex Portions)] A composition for the convex portion, Sample 3, was prepared using only the following raw materials. Resin material: Polyurethane elastomer (glass transition temperature -50°C, melting peak top temperature 125°C, 166°C, aromatic polyether urethane)

[0117] (Examples 12 and 13) Polypropylene (PP) spunbond nonwoven sheet (manufactured by Asahi Kasei Corporation, product name "Eltas P03040", basis weight 40g / m 2 ) on one side of a polyethylene film (20g / m 2 ) was used as a supporting substrate, and the adhesive composition was applied to the laminated surface side. A cleaning sheet as shown in Fig. 1 and Fig. 2A was formed.

[0118] Example 14 A cleaning sheet having the configuration shown in Table 3 was produced using the following composition as the adhesive composition, the following composition of Sample 4 as the composition for the protrusions, and the nonwoven fabric sheet described in Example 12 (but without lamination) as the supporting substrate. Both the adhesive composition and the composition for the protrusions were directly applied to the supporting substrate, and the protrusions and adhesive layer were formed in streaks, as shown in Figures 1 and 2B. [Preparation of adhesive (composition)] The following raw materials were mixed to prepare a rubber-based adhesive (SIS-based adhesive composition). Base polymer: styrene-isoprene-styrene block copolymer (SIS) Zeon Corporation product name "Quintac 3520" / 100 parts by weight Tackifier resin: Unhydrogenated hydrocarbon resin Manufactured by ENEOS Product name “T-REZ RC093” / 130 parts by mass Plasticizer: Naphthenic process oil Idemitsu Kosan Co., Ltd. Product name "Diana Process Oil NS90S" / 100 parts by weight [Preparation of Constituent Members for Convex Portions (Composition for Convex Portions)] A composition for the convex portion, Sample 4, was prepared from the following raw materials. Resin material: Ethylene-vinyl acetate copolymer (EVA) Tosoh Corporation Product name "Ultrasen 684" / 100 parts by weight Wax: Hydrocarbon-based Sasol Wax C80 (product name) with a needle penetration of 4 to 9 / 225 parts by weight Mixed raw materials: Polyolefin resin / calcium carbonate mixture (mass ratio 20 / 80) Nitto Funka Kogyo Co., Ltd. Product name "Calpet A" / 250 parts by weight (including 200 parts by weight of calcium carbonate) Then, a protrusion (stripe-like) having a plurality of linear members was formed as shown in Fig. 1. Note that, as shown in Fig. 2B, the protrusion was formed so that the linear members were in direct contact with the supporting substrate.

[0119] Example 15 A cleaning sheet having the configuration shown in Table 3 was produced using the same adhesive composition as in Example 14, the composition for the protrusions of Sample 5 below, and the nonwoven fabric sheet described in Example 12 (but not laminated) as a supporting substrate. As shown in Figures 1 and 2B, the protrusions and adhesive layer were each formed in a streaky shape. [Preparation of Constituent Members for Convex Portions (Composition for Convex Portions)] A composition for the convex portion, Sample 5, was prepared from the following raw materials. Resin material: Linear low density polyethylene resin (LLDPE) Prime Polymer Co., Ltd. Product name "Evolue SP1071C" / 100 parts by weight Wax: Hydrocarbon-based Sasol Wax C80, needle penetration 4-9 / 143 parts by mass Mixed raw materials: Polyolefin resin / calcium carbonate mixture (mass ratio 20 / 80) Nitto Funka Kogyo Co., Ltd. Product name "Calpet A" / 143 parts by weight (including 114 parts by weight of calcium carbonate)

[0120] (Examples 16 to 18) The number of linear members, the average height of the protrusions, etc. were changed as shown in Table 3 to produce each cleaning sheet.

[0121] (Example 19) A cleaning sheet having the configuration shown in Table 3 was manufactured using the same adhesive composition as in Example 14, a polyamide resin (manufactured by Daicel-Evonik, product name "Vestamelt 722GETR") as the material for Sample 6 for the convex parts, and the nonwoven fabric sheet described in Example 12 (but not laminated) as the supporting substrate. As shown in Figures 1 and 2B, the convex parts and the adhesive layer were each formed in a streaky shape.

[0122] (Reference example 20) A cleaning sheet having the configuration shown in Table 4 was manufactured using the same adhesive composition as in Example 14, ethylene-vinyl acetate copolymer resin (EVA) (manufactured by Tosoh Corporation, product name "Ultrathene 684") as the material for the convex parts of Sample 7, and the nonwoven fabric sheet described in Example 12 (but not laminated) as the supporting substrate. Note that the convex parts and adhesive layer were each formed in stripes as shown in Figures 1 and 2B.

[0123] (Examples 21 and 22) [Preparation of adhesive (composition)] The following raw materials were mixed to prepare a rubber-based adhesive (SIS-based adhesive composition). Base polymer: styrene-isoprene-styrene block copolymer (SIS) Zeon Corporation product name "Quintac 3421" / 100 parts by weight Tackifier resin: Unhydrogenated hydrocarbon resin Manufactured by ENEOS Product name “T-REZ RC093” / 130 parts by mass Plasticizer: Naphthenic process oil Idemitsu Kosan Co., Ltd. Product name "Diana Process Oil NS90S" / 100 parts by weight Using the above composition as the adhesive composition, the composition of Sample 8 below as the composition for the protrusions, and the nonwoven fabric sheet described in Example 12 (but without lamination) as the supporting substrate, a cleaning sheet having the configuration shown in Table 4 was produced. Both the adhesive composition and the composition for the protrusions were directly applied to the supporting substrate, and the protrusions and adhesive layer were formed in streaks, respectively, as shown in Figures 1 and 2B. [Preparation of Constituent Members for Convex Portions (Composition for Convex Portions)] A composition for the convex portion (Sample 8) was prepared from the following raw materials. Resin material: Linear low density polyethylene resin (LLDPE) Prime Polymer Co., Ltd. Product name "Evolue SP1071C" / 100 parts by weight Wax: Hydrocarbon-based Yasuhara Chemical Co., Ltd. Product name "Neowax" Penetration 5 / 143 parts by weight Mixed raw materials: Polyolefin resin / calcium carbonate mixture (mass ratio 20 / 80) Nitto Funka Kogyo Co., Ltd. Product name "Calpet A" / 143 parts by weight (including 114 parts by weight of calcium carbonate)

[0124] (Examples 23 and 24) [Preparation of adhesive (composition)] The following raw materials were mixed to prepare a rubber-based adhesive (SIS-based adhesive composition). Base polymer: styrene-isoprene-styrene block copolymer (SIS) Zeon Corporation product name "Quintac 3421" / 100 parts by weight Tackifier resin: Unhydrogenated hydrocarbon resin Manufactured by ENEOS Product name “T-REZ RC093” / 130 parts by mass Plasticizer: Naphthenic process oil Idemitsu Kosan Co., Ltd. Product name "Diana Process Oil NS90S" / 80 parts by weight Using the above composition as the adhesive composition, the above composition of Sample 8 as the composition for the protrusions, and the nonwoven fabric sheet described in Example 12 (but without lamination) as the supporting substrate, a cleaning sheet having the configuration shown in Table 4 was produced. Both the adhesive composition and the composition for the protrusions were directly applied to the supporting substrate, and the protrusions and adhesive layer were formed in stripes, respectively, as shown in Figures 1 and 2B.

[0125] (Comparative Examples 1 to 3) A cleaning sheet having the configuration shown in Table 5 was manufactured in the same manner as in Example 1, using only a polystyrene-based elastomer (styrene-hydrogenated butadiene copolymer SEBS, glass transition temperature -16°C, top melting peak temperature 102, 121°C) as the material for the convex parts of Sample 9.

[0126] <Physical properties of convex part constituent material> As described below, the following physical properties were measured by nanoindentation.

[0127] (Nanoindentation method) The hardness and elastic modulus of the convex portion were measured by nanoindentation in accordance with ISO14577. Specifically, the measurements were performed under the following measurement conditions. The indenter had a pressing depth of 5 μm. The measurements were performed at 25° C. At least three measurements were performed to calculate the average value. The details of the measurement method are as follows. The cleaning sheet was cut in the thickness direction with a trimming knife to cut out the components of the convex parts. A sample consisting of only the components of the convex parts was used for measurement. A cross section was prepared with an ultramicrotome under freezing conditions (-30°C), and then fixed to a specified support (brass stand) to prepare the measurement sample. Equipment: Nanoindenter "Triboindenter" manufactured by Hysitron Indenter used: Berkovich type diamond indenter (triangular pyramid type indenter) Measurement mode: Single push mode Measurement temperature: room temperature (25℃) Indentation depth: 5000nm (5μm) Push speed: 500nm / sec Extraction speed: 500 nm / sec The following physical properties were calculated from the measurement results. The measurement conditions are shown in Figure 9A, and a schematic measurement chart is shown in Figure 9B. "Hardness" It was calculated by dividing the "load when the indenter was pressed deepest (maximum load Pmax)" by the "area of ​​contact between the indenter and the measurement sample (contact projected area B)". "Elastic modulus" It was calculated using the above-mentioned formula (3) using the "slope of the tangent at the maximum load of the unloading curve (tangent stiffness S = dP / dh)" and the "area of ​​contact between the indenter and the measurement sample (contact projected area B)". "Load curve slope [μN / nm]" This mainly corresponds to the compressive elastic modulus. The higher the value, the less likely the material is to be distorted by stress. "Minimum load on load curve [μN]" This is the minimum load value on the load curve. The more negative the value, the greater the wettability. "Minimum load on unloading curve [μN]" This is the minimum load value in the unloading curve. The larger the value in the negative direction, the greater the adhesive force (adhesive force). "Displacement of unloading curve [nm]" This is the amount of change in displacement in the unloading curve. The larger the value in the positive direction, the higher the stringiness, etc. (assuming the adhesiveness is the same). For some of the cleaning sheets, the static and dynamic friction coefficients of the cleaning surface were measured by the method described above.

[0128] <Evaluation of slipperiness> The cleaning sheet produced by the above manufacturing method was attached to a commercially available wiper tool (Kao's Quickle Wiper main body), and wiped on a flooring surface (Daiken Corporation's Living Floor Art LVAT-MF) to evaluate slipperiness. The evaluation criteria are as follows. ◎: Very good slipperiness ○: Good slipperiness △: There is a sense of resistance to the floor when starting to slide, but once it starts sliding it is fine ×: There is a strong resistance to the floor and the product does not slide at all, or even if it does start to slide, there is a strong resistance

[0129] <Evaluation of dust capture ability> Within a flooring frame measuring 60 cm in length and 25 cm in width, 0.2 g of colored sand (CS-1004, 0.1 to 0.5 mm, obtained from Factory M Co., Ltd.) was spread almost uniformly as simulated garbage. One cleaning sheet manufactured as described above was attached to a commercially available wiper tool (Kao's Quickle Wiper main unit) and wiped over a 60 cm distance on a floor (Daiken Corporation's Living Floor Art LVAT-MF). Then, the wiper was wiped over a 70 cm distance. The dust capture rate (dust capture rate [%], mass basis) was calculated as follows: Dust capture rate [%] = (mass of sheet after wiping - mass of sheet before wiping) ÷ Amount of artificial garbage scattered (approx. 0.2g) × 100%

[0130] [Table 1]

[0131] [Table 2]

[0132] [Table 3]

[0133] [Table 4]

[0134] [Table 5]

[0135] As shown in Tables 1 to 4, the ratio of the exposed area of ​​the adhesive layer on the cleaning surface is 30% or more, and the ratio (H / L) of the average convex height (H: mm) from the tip of the convex portion to the adhesive concave portion to the average length (L: mm) of the shape of the adhesive concave portion in the first direction in which the average distance in the surface direction of the cleaning surface is the smallest is 15×10 -3 As described above, the cleaning sheets of the Examples exhibited good dust trapping properties, whereas the cleaning sheets of the Comparative Examples exhibited inferior dust trapping properties compared to the Examples.

[0136] As can be seen from the above results, the cleaning surface has projections and recesses, the adhesive recesses (adhesive layer) between adjacent projections are exposed, the exposure rate is 30% or more, and the above-mentioned ratio (H / L) is 15×10 -3 The above cleaning sheet has at least good dirt trapping properties. [Explanation of symbols]

[0137] 1: Cleaning sheet, 10: cleaning surface; 12: convex portion; 14: adhesive concave portion; 20: Non-cleaning surface, 30: Constituent member of the protrusion; 40: Adhesive layer, 50: Supporting base material, A: Spacing, 100: cleaning tools, 110: gripping member, 120: seat fixing part, 130: universal joint, 140: Radial slits.

Claims

1. A cleaning sheet having a cleaning surface that is brought into sliding contact with the surface of an object to be cleaned, The cleaning surface has projections and recesses, and is used by bringing tips of the projections into sliding contact with the object to be cleaned; the convex portions are constituted by members formed at intervals in a surface direction of the cleaning surface, and the hardness of the members measured by a nanoindentation method is 10.0 MPa or more; the cleaning surface further has an adhesive recess having a higher adhesive strength than the member and exposed on the cleaning surface; an adhesive layer extending in a surface direction of the cleaning surface and disposed in at least a part of the space between the members, at least a part of the adhesive layer constituting the adhesive recess, and a ratio of an exposed area of ​​the adhesive layer to the cleaning surface being 30% or more; The ratio (H / L) of the average convex height (H: mm) from the tip of the convex portion to the adhesive concave portion to the average length (L: mm) of the shape of the adhesive concave portion in the first direction in which the average length of the interval in the surface direction is the smallest is 15×10 －３ That's it for the cleaning sheet.

2. The cleaning sheet according to claim 1 , wherein a ratio of an exposed area of ​​the adhesive layer to the cleaning surface is greater than 50%.

3. The average convex height (H) from the tip of the convex portion to the adhesive concave portion is 1000×10 －３ 3. The cleaning sheet according to claim 1, wherein the thickness of the cleaning sheet is equal to or less than mm.

4. The average convex height (H) is 500×10 －３ 4. The cleaning sheet according to claim 3, wherein the thickness of the cleaning sheet is equal to or less than mm.

5. The average convex height (H) is 300×10 －３ The cleaning sheet according to claim 4, wherein the thickness of the cleaning sheet is equal to or less than mm.

6. The cleaning sheet according to any one of claims 1 to 5, wherein an average length (L) of the shape of the adhesive recesses in a first direction in which the average length of the intervals in the surface direction is smallest is 0.3 mm or more.

7. The cleaning sheet according to claim 6, wherein the average length (L) is 0.5 mm or more.

8. The cleaning sheet according to claim 7, wherein the average length (L) is 0.8 mm or more.

9. The cleaning sheet according to claim 8, wherein the average length (L) is 1.0 mm or more.

10. 10. The cleaning sheet according to claim 1, wherein a minimum load in a load curve when the member of the protrusions is measured by a nanoindentation method is −0.40 μN or more and 0 μN or less.

11. The cleaning sheet according to claim 10, wherein a minimum load in a load curve when the member of the protrusions is measured by a nanoindentation method is −0.10 μN or more and 0 μN or less.

12. The cleaning sheet according to any one of claims 1 to 11, wherein a minimum load in an unloading curve when the member of the convex portion is measured by a nanoindentation method is -1.50 µN or more and 0 µN or less.

13. 13. The cleaning sheet according to claim 12, wherein a minimum load in an unloading curve when the member of the protrusions is measured by a nanoindentation method is −0.10 μN or more and 0 μN or less.

14. The cleaning sheet according to any one of claims 1 to 13, wherein the cleaning surface has a static friction coefficient of 1.00 or less.

15. The probe tack of the adhesive layer measured by a probe tack method is 1.0 kN / m ２ More than 500.0kN / m ２ The cleaning sheet according to any one of claims 1 to 14, wherein:

16. The cleaning sheet according to any one of claims 1 to 15, wherein the member of the protrusions contains at least one of wax, hardened resin, and inorganic powder.

17. The cleaning sheet according to any one of claims 1 to 16, wherein the member of the convex portion contains at least one of a polyolefin resin, an ethylene-vinyl acetate copolymer resin (EVA), a styrene-based thermoplastic elastomer resin, an acrylic resin, a polyvinyl chloride resin, a polyester resin, a polyurethane resin, a polyimide resin, a polyamide resin, and a polycarbonate resin.

18. The cleaning sheet according to claim 16, wherein the members of the convex portions contain an extender pigment as the inorganic powder.

19. The cleaning sheet according to any one of claims 1 to 18, wherein the cleaning surface is formed on both sides.

20. A method for producing the cleaning sheet according to any one of claims 1 to 19, comprising the steps of: The method for producing a cleaning sheet includes forming the members of the protrusions by coating.

21. The cleaning sheet has a support substrate, The method for producing a cleaning sheet according to claim 20, wherein the members of the protrusions are formed by overlaying them on the supporting substrate by coating.

22. The cleaning sheet has a support substrate and an adhesive layer overlying the support substrate, The method for producing a cleaning sheet according to claim 20, wherein the members of the convex portions are formed by coating on the adhesive layer.

23. The cleaning sheet according to any one of claims 1 to 19 in a rolled state, or A laminate in which a plurality of the cleaning sheets according to any one of claims 1 to 19 are laminated in the thickness direction.

24. The cleaning sheet according to any one of claims 1 to 19, and a sheet fixing part to which the cleaning sheet is detachably attached.

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