Covering sheet and method for using the same

Abstract

To provide a covering sheet that resists oozing of liquid even when impregnated with a large quantity of liquid, and that suppresses wetting of an article contacting a second surface.SOLUTION: A covering sheet 10A has a first surface and a second surface positioned opposite the first surface. The covering sheet is employed to cover a target surface by contacting the first surface with the target surface. The covering sheet is impregnated with an impregnating liquid. An impregnation rate of a first fiber layer including the first surface is at least 50 mass% higher than an impregnation rate of a second fiber layer including the second surface. The impregnating liquid comprises water and a water-soluble polymer. The impregnating liquid contains 60 mass% or more and 99 mass% or less of water, and 0.0025 mass% or more and 0.8 mass% or less of the water-soluble polymer.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a covering sheet used to cover a target surface and a method for using the same. [Background technology]

[0002] Various techniques are known for covering a target surface by contacting a sheet impregnated with a chemical solution with the target surface. For example, Patent Document 1 describes a cooling sheet agent in which three layers of nonwoven fabric are entangled and bonded together. This cooling sheet agent has a middle layer of superabsorbent nonwoven fabric made of acrylic fibers that have been treated with superabsorbent processing, a nonwoven fabric sheet made of rayon fibers on the side of the middle layer that comes into contact with the skin, and a nonwoven fabric sheet made of polyester fibers or the like on the outer side of the middle layer. The middle layer is impregnated with a liquid that has a cooling effect.

[0003] Patent Document 2 describes a skin application sheet to be impregnated with a cosmetic preparation, in which an ultrafine fiber layer containing ultrafine fibers with a fineness of 0.5 dtex or less is positioned on one or both surfaces of a hydrophilic fiber layer containing hydrophilic fibers, the hydrophilic fiber layer and the ultrafine fiber layer being integrated, and the ultrafine fiber layer is the surface that comes into contact with the skin. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-051260 [Patent Document 2] International Publication No. 2006 / 016601 Pamphlet Summary of the Invention [Problem to be solved by the invention]

[0005] In sheets made of nonwoven fabric impregnated with an impregnating liquid, such as those described in Patent Documents 1 and 2, it is desirable to impregnate a large amount of the impregnating liquid from the viewpoint of supplying a sufficient amount of the impregnating liquid to the target surface over a long period of time. However, if the body is covered with a sheet impregnated with a large amount of the impregnating liquid, there is a risk that the impregnating liquid will seep out onto the outer surface of the sheet and wet the clothing. Therefore, an object of the present invention is to improve a liquid-impregnated coating sheet, more specifically, to make the coating sheet less likely to ooze out even when a large amount of liquid is impregnated, and to make it less likely to wet an article that comes into contact with the coating sheet. [Means for solving the problem]

[0006] The present invention provides a coating sheet having a first surface and a second surface located opposite to the first surface, which is used to coat a target surface by bringing the first surface into contact with the target surface, and which is impregnated with an impregnation liquid. In one embodiment, the coating sheet has a wettability of the first fiber layer comprising the first surface that is 50% by mass or more higher than a wettability of the second fiber layer comprising the second surface. In one embodiment, the impregnation liquid comprises water and a water-soluble polymer. In one embodiment, the content of the water in the impregnation liquid is 60% by mass or more and 99% by mass or less, and the content of the water-soluble polymer is 0.0025% by mass or more and 0.8% by mass or less.

[0007] The present invention also provides a method for using a coating sheet, which has a first surface and a second surface opposite to the first surface and is impregnated with an impregnation liquid, and which comprises covering a target surface with the first surface of the coating sheet. In one embodiment, the coating sheet has an impregnation rate of the first fiber layer that is 50% by mass or more higher than an impregnation rate of the second fiber layer. In one embodiment, the impregnation liquid comprises water and a water-soluble polymer. In one embodiment, the content of the water in the impregnation liquid is 60% by mass or more and 99% by mass or less, and the content of the water-soluble polymer is 0.0025% by mass or more and 0.8% by mass or less. [Effects of the Invention]

[0008] According to the present invention, a coating sheet is provided which has high uneven distribution of liquid within the sheet, so that even if a large amount of liquid is impregnated, the liquid does not easily seep out, and articles that come into contact with the sheet are not easily wetted. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1(a) is a plan view showing one embodiment of the application sheet of the present invention, and FIG. 1(b) is a perspective view showing a usage form of the application sheet shown in FIG. 1(a). [Figure 2] FIG. 2(a) is a plan view showing another embodiment of the application sheet of the present invention, and FIG. 2(b) is a perspective view showing a usage form of the application sheet shown in FIG. 2(a). [Figure 3] FIG. 3(a) is a plan view showing still another embodiment of the application sheet of the present invention, and FIG. 3(b) is a perspective view showing a usage form of the application sheet shown in FIG. 3(a). DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention will be described below based on preferred embodiments. The coating sheet of the present invention is a wet sheet comprising a base sheet and an impregnation liquid impregnated into the base sheet. The coating sheet has a first side and a second side opposite the first side. The coating sheet has a first fiber layer having the first side and a second fiber layer having the second side. In other words, the coating sheet has a multilayer structure. The coating sheet may have a two-layer structure consisting of a first fiber layer and a second fiber layer, or a three-layer or greater structure with at least one other fiber layer between the first fiber layer and the second fiber layer. A sheet in which a film layer is disposed between the first fiber layer and the second fiber layer does not fall within the scope of the coating sheet of the present invention, because such a film layer prevents the impregnation rate of the first fiber layer (including the first side) from being 20% by mass or more higher than the impregnation rate of the second fiber layer (including the second side).

[0011] Whether the coating sheet has a two-layer structure consisting of only the first and second fiber layers, or a three-layer structure including the first and second fiber layers, the first and second fiber layers form the outermost surfaces of the coating sheet. Therefore, no other layers exist outside the first and second surfaces. For example, no other fiber layers exist outside the first and / or second surfaces. Furthermore, no film layers exist outside the first and / or second surfaces. In this specification, the term "coating sheet" may refer to the base sheet itself before being impregnated with the impregnation liquid, or may refer to the coating sheet obtained by impregnating the base sheet with the impregnation liquid, depending on the context.

[0012] In the coating sheet of the present invention, the first fiber layer and the second fiber layer are distinguished by, for example, the fiber material, composition, thickness, length, and / or cross-sectional shape, etc. For example, when the coating sheet has a structure consisting of only two layers, the first fiber layer and the second fiber layer, the first fiber layer and the second fiber layer can be distinguished by the boundary surface where the fibers have different thicknesses, as observed in an electron microscope image of a cross section of the coating sheet in the thickness direction.

[0013] The coating sheet of the present invention is used to coat a target surface. As used herein, "coating a target surface" includes, for example, covering the entire or partial area of the target surface with the coating sheet of the present invention, attaching the coating sheet of the present invention to the entire or partial area of the target surface, or contacting the entire or partial area of the target surface with the coating sheet of the present invention. Specific examples of target surfaces will be described later. When coating a target surface with the coating sheet of the present invention, the first surface is brought into contact with the target surface to coat the target surface. Unless there are special circumstances, the second surface is not brought into contact with the target surface to coat the target surface.

[0014] The coating sheet is a fiber sheet entirely composed of fibers. In one embodiment, the constituent fibers of the coating sheet are hydroentangled, thereby maintaining the sheet shape of the coating sheet. Hydroentanglement of the constituent fibers of the coating sheet improves the tactile feel of the coating sheet, making it less likely to cause discomfort when applied to a target surface, such as human skin. From this perspective, it is desirable that the constituent fibers of the coating sheet maintain their sheet shape solely through hydroentanglement. However, the constituent fibers of the coating sheet may be fused at their intersections, as long as the tactile feel is not impaired.

[0015] The coating sheet of the present invention preferably has a sufficient gradient in the impregnation rate of the impregnating liquid in the thickness direction, since this increases the uneven distribution of the liquid along the thickness direction of the sheet. This increases the uneven distribution of the liquid, making it easier for the impregnating liquid to be released from the first fiber layer toward the target surface and less likely for the impregnating liquid to seep out from the second fiber layer, which is the opposite side of the target surface. As a result, the coating sheet of the present invention provides a dry feel on the second side, making it less likely for articles, such as clothing, that come into contact with the second side to become wet. From the above viewpoints, the impregnation rate of the first fiber layer is at least 50% by mass higher than the impregnation rate of the second fiber layer, preferably at least 160% by mass higher, and more preferably at least 200% by mass higher. On the other hand, from the viewpoint of continuously supplying a sufficient amount of impregnation liquid to the target surface, it is preferable that the impregnation rate of the first fiber layer is 600% by mass or less higher than the impregnation rate of the second fiber layer. Taking the above into consideration, the impregnation rate of the first fiber layer is preferably 50% by mass or more and 600% by mass or less, more preferably 160% by mass or more and 600% by mass or less, and even more preferably 200% by mass or more and 600% by mass or less, higher than the impregnation rate of the second fiber layer.

[0016] From the viewpoint of supplying a sufficient amount of the impregnation liquid to the target surface and from the viewpoint of providing a sufficient gradient in the impregnation rate of the impregnation liquid in the thickness direction of the covering sheet, the value of P1 / P2, which is the ratio of the impregnation rate P1 in the first fiber layer to the impregnation rate P2 in the second fiber layer, is preferably 1.05 or more, more preferably 1.10 or more, and even more preferably 1.15 or more. The value of P1 / P2 may also be 4.0 or less.

[0017] As described above, in the present invention, by creating a gradient in impregnation rate between the first and second surfaces of the coating sheet, uneven distribution of the impregnating liquid in the thickness direction of the coating sheet is improved. From this perspective, it is preferable that the second fiber layer has a lower impregnating liquid retention capacity than the first fiber layer. Therefore, in the present invention, it is advantageous to make the average fiber diameter of the fibers contained in the second fiber layer larger than the average fiber diameter of the fibers contained in the first fiber layer. This makes it easier to create a capillary force in the second fiber layer that is smaller than that in the first fiber layer. As a result, it is possible to lower the impregnating liquid retention capacity of the second fiber layer than that of the first fiber layer. From the viewpoint of making the average fiber diameter of the fibers contained in the first fiber layer smaller than the average fiber diameter of the fibers contained in the second fiber layer, it is preferable that the average fiber diameter of the fibers constituting the first fiber layer on the first surface be smaller than the average fiber diameter of the fibers constituting the second fiber layer on the second surface.

[0018] To make the retention of the impregnation liquid in the second fiber layer lower than that of the first fiber layer, the average fiber diameter d2 of the fibers constituting the second fiber layer on the second surface (hereinafter also referred to as "average fiber diameter of the fibers on the second surface") is preferably 7.5 μm or more, more preferably 8.0 μm or more, and even more preferably 8.5 μm or more. Furthermore, from the viewpoint of preventing the rigidity of the coating sheet from becoming excessively high and reducing the feeling of use, the average fiber diameter d2 of the fibers on the second surface is preferably 35.0 μm or less, more preferably 34.0 μm or less, and even more preferably 33.0 μm or less. Considering the above, the average fiber diameter d2 of the fibers on the second surface is preferably 7.5 μm or more and 35.0 μm or less, more preferably 8.0 μm or more and 34.0 μm or less, and even more preferably 8.5 μm or more and 33.0 μm or less.

[0019] On the other hand, from the viewpoint of supplying a sufficient amount of impregnation liquid to the target surface, the average fiber diameter of the fibers constituting the first fiber layer is preferably 11.9 μm or less on the first side, provided that the average fiber diameter is smaller than the average fiber diameter of the fibers on the second side. Hereinafter, this average fiber diameter is also referred to as the "average fiber diameter of the fibers on the first side." By using fibers having this average fiber diameter, a high capillary force is exerted, allowing a sufficient amount of impregnation liquid to be retained in the first fiber layer. From the viewpoint of further enhancing this advantage, the average fiber diameter d1 of the fibers on the first side is more preferably 11.5 μm or less, and even more preferably 11.0 μm or less. From the viewpoint of exerting a high capillary force, the thinner the fibers constituting the first fiber layer, the more desirable. However, from the viewpoint of cost, thinner fibers are disadvantageous. Therefore, in consideration of cost, the average fiber diameter d1 of the fibers in the first surface is preferably 3.5 μm or more, more preferably 5.0 μm or more, and even more preferably 7.0 μm or more. Considering the above, the average fiber diameter d1 of the fibers on the first surface is preferably 3.5 μm or more and 11.9 μm or less, more preferably 5.0 μm or more and 11.5 μm or less, and even more preferably 7.0 μm or more and 11.0 μm or less.

[0020] The average fiber diameter of the fibers on the first and second surfaces is measured by the following method. The coating sheet is observed perpendicular to the cross section in the thickness direction using a scanning electron microscope (SEM) at a magnification at which the fibers can be seen, and 20 fibers are randomly selected from the first surface and its vicinity. The length of a line drawn perpendicular to the longitudinal direction of each fiber is measured and used as the fiber diameter. The average fiber diameter is calculated by taking the arithmetic mean of these fiber diameters. The average fiber diameter of the fibers on the second surface is also measured in the same way.

[0021] The fibers contained in the first fiber layer and the fibers contained in the second fiber layer may each independently be staple fibers or continuous filaments. The type of fibers to be used may be selected depending on the method for producing the coating sheet.

[0022] From the viewpoint of supplying a sufficient amount of impregnation liquid to the target surface, the basis weight of the first fiber layer is set to 10 g / m 2 It is preferable that the weight is 20 g / m or more. 2 More preferably, it is 30 g / m or more. 2 More preferably, it is more than this. From the viewpoint of preventing excessive impregnation, improving the handling of the application sheet, and providing a good feel to the skin immediately after application, for example, the basis weight of the first fiber layer is set to 120 g / m 2 It is preferable that the density is 100 g / m or less. 2 More preferably, it is 80 g / m or less. 2 It is even more preferred that: Considering the above, the basis weight of the first fiber layer is 10 g / m 2 More than 120g / m 2 Preferably, it is 20 g / m or less. 2 More than 100g / m 2 More preferably, it is 30 g / m or less. 2 More than 80g / m 2 It is even more preferred that:

[0023] From the viewpoint of imparting sufficient strength to the covering sheet and effectively suppressing the seepage of the impregnation liquid, the basis weight of the second fiber layer is set to 20 g / m 2 It is preferable that the content is 30 g / m or more. 2 More preferably, it is equal to or greater than this. In order to prevent the rigidity of the covering sheet from becoming excessively high and to provide a large gradient in the impregnation rate between the second fiber layer and the first fiber layer, the basis weight of the second fiber layer is set to 70 g / m 2 Preferably, it is 50 g / m or less. 2 More preferably, it is 40 g / m or less. 2It is even more preferred that: Considering the above, the basis weight of the second fiber layer is 20 g / m 2 More than 70g / m 2 Preferably, it is 30 g / m or less. 2 More than 50g / m 2 More preferably, it is 30 g / m or less. 2 More than 40g / m 2 It is even more preferred that:

[0024] From the viewpoint of increasing the uneven distribution of the impregnation liquid within the coating sheet and suppressing the seepage of the impregnation liquid from the second surface, it is preferable that the basis weight B1 of the first fiber layer and the basis weight B2 of the second fiber layer are approximately the same. Specifically, the value of B2 / B1, which is the ratio of the basis weight B2 of the second fiber layer to the basis weight B1 of the first fiber layer, is preferably 0.2 to 2.0, more preferably 0.2 to 1.3, and even more preferably 0.2 to 1.1.

[0025] The first fiber layer in the coating sheet of the present invention contains either or both of hydrophilic and hydrophobic fibers. From the viewpoint of a good feel on the target surface, it is preferable that the first fiber layer contains a larger amount of hydrophilic fibers than hydrophobic fibers. This makes it possible to provide a coating sheet that feels good to the touch when the coating sheet is used to cover the target surface with its first surface in contact with the target surface. For example, the first fiber layer preferably contains 10% by mass or more of hydrophilic fibers, more preferably 20% by mass or more, even more preferably 30% by mass or more, and even more preferably the first fiber layer is made of hydrophilic fibers. When the first fiber layer is made of hydrophilic fibers, the first fiber layer is composed substantially of only hydrophilic fibers, excluding hydrophobic fibers that are inevitably mixed in during the manufacturing process of the coating sheet. Examples of hydrophobic fibers that are inevitably mixed in during the manufacturing process of the coating sheet include hydrophobic fibers that can be contained in the second fiber layer described below. It is to be noted that a part of the fibers constituting the first fiber layer may unavoidably penetrate into the second fiber layer.

[0026] The second fibrous layer may also include either or both hydrophilic and hydrophobic fibers. In the coating sheet of the present invention, the first fiber layer mainly retains the impregnation liquid, but a portion of the impregnation liquid is also retained in the second fiber layer. From this viewpoint, it is preferable that the second fiber layer contains at least hydrophilic fibers. The type of hydrophilic fibers contained in the second fiber layer may be the same as or different from the type of hydrophilic fibers contained in the first fiber layer. It is to be noted that a part of the hydrophilic fibers constituting the second fiber layer may inevitably penetrate into the first fiber layer.

[0027] When the second fiber layer contains hydrophilic fibers, from the viewpoint of lowering the retention of the impregnation liquid in the second fiber layer compared to that in the first fiber layer, the average fiber diameter of the hydrophilic fibers constituting the second fiber layer on the second surface (hereinafter also referred to as "average fiber diameter of the hydrophilic fibers on the second surface") is preferably 9.0 μm or more and 27.0 μm or less, more preferably 12.0 μm or more and 25.0 μm or less, and even more preferably 13.0 μm or more and 22.0 μm or less, provided that the average fiber diameter is the same as or larger than the average fiber diameter of the hydrophilic fibers constituting the first fiber layer on the first surface.

[0028] From the viewpoint of fully realizing the gradient of impregnation rate between the first and second surfaces of the coating sheet, when the average fiber diameter of the fibers on the second surface is d2 and the average fiber diameter of the fibers on the first surface is d1, the value of d1 / d2, which is the ratio of d1 to d2, is preferably 0.9 or less, more preferably 0.8 or less, and even more preferably 0.7 or less. Furthermore, from the viewpoint of preventing deterioration in the feeling of use of the application sheet, the value of d1 / d2 is preferably 0.2 or more, and more preferably 0.4 or more. Taking the above into consideration, the value of d1 / d2 is preferably 0.2 or more and 0.9 or less, more preferably 0.4 or more and 0.8 or less, and even more preferably 0.4 or more and 0.7 or less. The average fiber diameter d1 of the fibers on the first surface is substantially the same as the average fiber diameter D1 of the hydrophilic fibers on the first surface when the first fiber layer does not contain hydrophobic fibers. Similarly, the average fiber diameter d2 of the fibers on the second surface is substantially the same as the average fiber diameter D2 of the hydrophilic fibers on the second surface when the second fiber layer does not contain hydrophobic fibers.

[0029] As described above, the second fiber layer preferably contains at least hydrophilic fibers. The proportion of hydrophilic fibers in the second fiber layer is preferably 10% by mass or more, more preferably 15% by mass or more, and even more preferably 20% by mass or more, from the viewpoint of ensuring the impregnation rate of the entire coating sheet with the impregnation liquid. There is no particular upper limit to the proportion of hydrophilic fibers in the second fiber layer, and the second fiber layer may comprise 100% by mass of hydrophilic fibers. When the second fiber layer contains both hydrophilic and hydrophobic fibers, the proportion of hydrophilic fibers is preferably 95% by mass or less, more preferably 80% by mass or less, and even more preferably 40% by mass or less.

[0030] The second fibrous layer may optionally include hydrophobic fibers. When the second fiber layer contains hydrophobic fibers, a portion of the hydrophobic fibers may unavoidably penetrate into the first fiber layer. When the second fiber layer contains hydrophobic fibers, the average fiber diameter D3 of the hydrophobic fibers at the second surface is not particularly limited. However, in relation to the average fiber diameter D2 of the hydrophilic fibers at the second surface, the value of D3 / D2 is preferably 0.15 or more and 3.00 or less, more preferably 0.20 or more and 2.90 or less, and even more preferably 0.25 or more and 2.80 or less, from the viewpoint of achieving a large difference in fiber diameter between the constituent fibers of the first fiber layer and the constituent fibers of the second fiber layer.

[0031] When the second fibrous layer contains hydrophobic fibers, the hydrophobic fibers may be staple fibers or continuous filaments, and the choice of which fibers to use may be determined depending on the method of manufacturing the coating sheet.

[0032] In this specification, a fiber is defined as a hydrophobic fiber if the contact angle between the fiber surface and water is 90 degrees or more when a droplet of pure water is dropped onto the fiber in an environment of 25° C., and a fiber is defined as a hydrophilic fiber if the contact angle between the fiber surface and water is less than 90 degrees. The contact angle can be measured according to the method described in, for example, JP 2015-142721 A.

[0033] The hydrophilic fibers contained in the first fiber layer and / or the second fiber layer refer to both fibers whose fiber surfaces are inherently hydrophilic, and fibers whose fiber surfaces are inherently hydrophobic but have been subjected to a hydrophilization treatment to be rendered hydrophilic. Examples of fibers whose fiber surfaces are inherently hydrophilic include natural cellulose fibers such as rayon, cotton, cupra, lyocell, and wood pulp, regenerated cellulose fibers, and silk. These fibers can be used alone or in combination of two or more. Rayon is particularly preferred because it significantly improves flexibility in a wet state and therefore improves adhesion between the coating sheet and the target surface. Although the fiber surface is inherently hydrophobic, examples of fibers that have been subjected to a hydrophilization treatment to impart hydrophilicity include fibers made of thermoplastic resins having fiber-forming ability, such as polyolefin resins, acrylic resins, and polyester resins, to whose surfaces a hydrophilizing agent has been applied.

[0034] Examples of the hydrophobic fibers contained in the first fiber layer and / or the second fiber layer include fibers made of thermoplastic resins having fiber-forming properties, such as polyolefin resins, acrylic resins, and polyester resins. Composite fibers containing two or more of these thermoplastic resins can also be used.

[0035] Comparing the first and second fiber layers, as described above, the fibers constituting the first fiber layer preferably have a smaller average fiber diameter than the fibers constituting the second fiber layer. In addition, the first fiber layer preferably has a higher fiber density than the second fiber layer. In other words, the first fiber layer preferably has a state in which fine fibers are densely present. On the other hand, the second fiber layer preferably has a lower fiber density than the first fiber layer, that is, the second fiber layer preferably has thick fibers sparsely present. Because the first and second fiber layers are in these states, the impregnating liquid impregnated in the covering sheet is more likely to migrate from the second surface side to the first surface side. As a result, in the covering sheet, the impregnation rate of the first fiber layer is higher than that of the second fiber layer, which effectively creates an impregnation rate gradient between the first and second surfaces. That is, the impregnation rate of the first surface is higher than that of the second surface. As a result, the second surface of the covering sheet feels dry, and articles that come into contact with the second surface are less likely to get wet.

[0036] The impregnating liquid contained in the coating sheet of the present invention is selected to have an appropriate composition depending on the type of target surface to be covered by the coating sheet. In terms of handleability, safety, etc., the impregnating liquid is preferably an aqueous liquid containing water as a medium.

[0037] When the impregnating liquid is an aqueous liquid, when the target surface is covered with the coating sheet, the second surface side is less likely to become wet, while the first surface side has a high impregnation rate of the impregnating liquid. Therefore, the impregnating liquid is supplied to the target surface, and the cooling effect is enhanced due to the efficient heat exchange, thereby cooling the target surface. When the target surface is human skin, covering the skin with the coating sheet can impart a cooling sensation to the subject. In other words, the coating sheet of the present invention can be used as a cooling sheet. Note that the cooling sensation in this specification encompasses both the cooling effect of the actual cooling of the target surface and the cooling sensation of feeling cold. Therefore, the coating sheet of the present invention is a cooling sheet used to impart a cooling sensation to the subject by covering the skin, and also a cooling sheet used to impart a cooling effect to the subject by covering the skin. Alternatively, if the target surface is human skin, the texture of the target's skin can be improved by adding a moisturizing component or an anti-inflammatory agent to the impregnation solution. In other words, the coating sheet of the present invention can be used as a skin quality improving sheet.

[0038] Examples of components other than water contained in the aqueous liquid include water-soluble polymers, water-soluble organic solvents, various surfactants, fragrances, cooling agents, preservatives, oils, pH adjusters, moisturizers, anti-inflammatory agents, and skin quality improving agents.

[0039] In particular, when the impregnation liquid contains water and a water-soluble polymer, the target surface can be stably coated with the coating sheet, and the impregnation liquid is less likely to seep out to the second surface, making it less likely to wet the second surface, which is preferable. From this viewpoint, the water content in the impregnation liquid is 60% by mass or more, preferably 65% by mass or more, and more preferably 70% by mass or more. The water content in the impregnation liquid is 99% by mass or less, preferably 95% by mass or less, and more preferably 90% by mass or less. Considering the above, the water content in the impregnation liquid is 60% by mass or more and 99% by mass or less, preferably 65% by mass or more and 95% by mass or less, and more preferably 70% by mass or more and 90% by mass or less.

[0040] On the other hand, the content of the water-soluble polymer in the impregnation liquid is 0.0025% by mass or more, preferably 0.005% by mass or more, and more preferably 0.01% by mass or more. The content of the water-soluble polymer in the impregnation liquid is 0.8% by mass or less, preferably 0.65% by mass or less, and more preferably 0.5% by mass or less. Taking the above into consideration, the content of the water-soluble polymer in the impregnation liquid is 0.0025% by mass or more and 0.8% by mass or less, preferably 0.005% by mass or more and 0.65% by mass or less, and more preferably 0.01% by mass or more and 0.5% by mass or less.

[0041] The water-soluble polymer contained in the impregnation liquid is preferably a thickening agent. By including such an agent in the impregnation liquid, the viscosity of the impregnation liquid becomes higher than the viscosity of water alone. As a result, the target surface can be more stably coated with the covering sheet, and the impregnation liquid is less likely to be released onto an article that comes into contact with the second surface, which is preferable. In this specification, the term "thickening agent" includes an agent whose viscosity (25°C) of a 0.1% by mass aqueous solution is 10 times or more the viscosity (25°C) of water. Examples of water-soluble polymers having a thickening effect include acrylic acid polymers, polysaccharides, cellulose or its derivatives (cellulose in which some of the hydrogen atoms of the hydroxyl groups have been substituted with, for example, nitro groups, acetyl groups, alkyl groups, carboxyalkyl groups, or hydroxyalkyl groups), polyvinylpyrrolidone, polyvinyl alcohol, polyvinyl butyral, polyethylene oxide, etc. These water-soluble polymers can be used alone or in combination of two or more. Among these water-soluble polymers, it is preferable to use at least one selected from acrylic acid-based polymers, polysaccharides, and cellulose or its derivatives, because when the target surface is covered with the covering sheet, the target surface is less likely to feel sticky.

[0042] Examples of acrylic acid-based polymers include polyacrylic acid, polyacrylates, (acrylic acid-methacrylic acid) copolymers, salts of (acrylic acid-methacrylic acid) copolymers, (acrylic acid-alkyl methacrylate) copolymers, carboxyvinyl polymers (carbomers), and alkyl-modified carboxyvinyl polymers. Examples of polysaccharides include sodium alginate, tolanthus gum, guar gum, xanthan gum, gum arabic, carrageenan, galactomannan, gelatin, casein, albumin, and pullulan. Examples of cellulose or its derivatives include carboxymethyl cellulose, carboxyethyl cellulose, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose.

[0043] It is preferable that the viscosity of the impregnating liquid at 25°C is 10 mPa s or more, because this increases the adhesion between the covering sheet and the target surface, allows the covering sheet to cover the target surface more stably, and makes it less likely that the impregnating liquid will seep out to the second surface, making it less likely that an article in contact with the second surface will become wet. From this perspective, the viscosity of the impregnating liquid at 25°C is more preferably 30 mPa s or more, and even more preferably 50 mPa s or more. The viscosity of the impregnating liquid at 25°C is preferably 1500 mPa s or less from the viewpoints of ease of impregnation with the impregnating liquid, of preventing the target surface from feeling sticky when covered with the covering sheet, and of facilitating transfer of the impregnating liquid from the second surface to the first surface. From these viewpoints, the viscosity of the impregnating liquid at 25°C is more preferably 1000 mPa s or less, and even more preferably 500 mPa s or less. Taking the above into consideration, the viscosity of the impregnation liquid at 25°C is preferably 10 mPa·s or more and 1500 mPa·s or less, more preferably 30 mPa·s or more and 1000 mPa·s or less, and even more preferably 50 mPa·s or more and 500 mPa·s or less.

[0044] The viscosity of the impregnation liquid is measured using the following method. A glass container filled with 50 g or 100 g of the impregnation liquid is immersed in a thermostatic water bath set to 25°C for at least two hours, and then the viscosity is measured using a BM viscometer (manufactured by Toki Sangyo Co., Ltd.). The measurement conditions are as follows: if the viscosity of the impregnation liquid is 1000 mPa·s or higher, use rotor No·3 (30 rpm, 1 minute); if it is 100 mPa·s to 999 mPa·s, use rotor No·2 (30 rpm, 1 minute); and if it is 99 mPa·s or lower, use rotor No·1 (60 rpm, 1 minute).

[0045] The impregnation liquid may contain other components in addition to the water-soluble polymer described above. Examples of other components include water-soluble organic solvents. Examples of water-soluble organic solvents include lower alcohols, propylene glycol, polyethylene glycol, and propylene glycol monomethyl ether. It is preferable that the aqueous liquid contains ethanol, since this effectively cools the target surface when the target surface is covered with the covering sheet. When the target surface is human skin, a sufficient cooling sensation can be imparted to the target surface.

[0046] The impregnation solution may contain a cooling agent. This can provide an even more cooling sensation when the dressing sheet is used to cover a human skin. Substances used in cosmetics and pharmaceuticals can be used as cooling agents without any particular limitations. For example, menthol, isopulegol, menthyl acetate, cineol, borneol, thymol, l-menthyl glyceryl ether, and derivatives thereof can be used. Other examples include menthyl lactate, 3-l-methoxypropanediol, N-ethyl-3-p-menthanecarboxamide, and essential oils containing menthol, such as peppermint oil and peppermint oil.

[0047] The impregnation liquid may contain a surfactant. In particular, when the impregnation liquid contains the above-mentioned cooling sensation agent, the inclusion of a surfactant improves the dispersibility of the cooling sensation agent. From this perspective, it is preferable to use, as the polyoxy surfactant, nonionic surfactants such as ethylene lauryl ether (preferably 5 to 10 E.O., particularly 6 E.O.), alkyl glyceryl ether, and polyoxyethylene hydrogenated castor oil (preferably 40 to 70 E.O., particularly 60 E.O.).

[0048] The impregnation solution may further contain moisturizing agents such as 1,3-butylene glycol, glycerin, and dipropylene glycol, preservatives such as methylparaben, ethylparaben, propylparaben, butylparaben, and phenoxyethanol, neutralizing agents such as potassium hydroxide, and pH adjusters such as edetate and succinic acid.

[0049] The impregnation rate, which is the amount of impregnation liquid contained in the coating sheet, or in other words, the ratio of the impregnation liquid to the base sheet, is preferably 150% by mass or more, more preferably 170% by mass or more, and even more preferably 200% by mass or more, from the viewpoint of the supply of the impregnation liquid to the target surface and the handleability of the coating sheet. From the same viewpoint, the impregnation rate is preferably 700% by mass or less, more preferably 600% by mass or less, and even more preferably 550% by mass or less. Taking the above into consideration, the impregnation rate is preferably 150% by mass or more and 700% by mass or less, more preferably 170% by mass or more and 600% by mass or less, and even more preferably 200% by mass or more and 550% by mass or less. In the present invention, since a gradient in the impregnation rate of the impregnation liquid occurs in the thickness direction of the coating sheet, a sufficient amount of impregnation liquid can be supplied to the target surface without excessively increasing the impregnation rate of the entire coating sheet. Of course, it goes without saying that the coating sheet of the present invention can retain a large amount of impregnation liquid.

[0050] The impregnation rate of the entire coating sheet is as described above, and the impregnation rate of the first fiber layer is preferably 200% by mass or more, more preferably 250% by mass or more, and even more preferably 300% by mass or more, from the viewpoint of supplying a sufficient amount of impregnation liquid to the target surface. From the viewpoint of ease of handling of the coating sheet, the impregnation rate in the first fiber layer is preferably 800% by mass or less, more preferably 750% by mass or less, and even more preferably 700% by mass or less. Considering the above, the impregnation rate in the first fiber layer after a gradient has developed in the impregnation rate of the impregnation liquid (i.e., after the coating sheet has been left to stand for a predetermined time) is preferably 200% by mass or more and 800% by mass or less, more preferably 250% by mass or more and 750% by mass or less, and even more preferably 300% by mass or more and 700% by mass or less. On the other hand, from the viewpoint of ease of handling of the covering sheet, the impregnation rate in the second fiber layer after the gradient in the impregnation rate of the impregnation liquid has been created is preferably 600% by mass or less, more preferably 500% by mass or less, and even more preferably 400% by mass or less, provided that it is lower than the impregnation rate in the first fiber layer.

[0051] Next, a preferred method for producing the coating sheet of the present invention will be described. As mentioned above, in one embodiment, the coating sheet of the present invention maintains its sheet shape by hydroentangling its constituent fibers. From this perspective, the substrate sheet constituting the coating sheet is preferably produced by the spunlace method. In other words, the substrate sheet is preferably a spunlace nonwoven fabric.

[0052] When manufacturing a base sheet by the spunlace method, a first web is prepared as the raw material for the first fiber layer, and a second web is prepared as the raw material for the second fiber layer. The second web preferably contains fibers with a larger diameter than the fibers contained in the first web. Both the first web and the second web can be manufactured using, for example, a carding machine.

[0053] The first and second webs are superimposed on each other to form a laminated web, and a water stream is sprayed onto the laminated web, thereby hydroentangling the constituent fibers of the first web, the constituent fibers of the second web, and the constituent fibers of the first and second webs. As a result, a base sheet is obtained that is made of a spunlace nonwoven fabric having a first fiber layer formed from the first web and a second fiber layer formed from the second web.

[0054] After the substrate sheet is obtained by the above method, the desired coating sheet can be obtained by impregnating the substrate sheet with a predetermined amount of impregnation liquid. If the substrate sheet is kept stationary after being impregnated with the impregnation liquid, a gradient will occur between the impregnation rates of the first and second fiber layers.

[0055] The covering sheet obtained in this manner can be used to cover various target surfaces. For example, it can be used to cover human skin to provide a cooling sensation. Therefore, the covering sheet of the present invention is useful, for example, when wanting to relieve heat while outdoors in hot weather. In this case, the covering sheet is used with the first side in contact with the skin and the second side facing outward. The first side of the covering sheet, i.e., the first fiber layer, retains the impregnating liquid at a high impregnation rate, allowing the impregnating liquid to be smoothly supplied to the skin through the first side, enhancing the cooling effect. On the other hand, the second side of the covering sheet, i.e., the second fiber layer, has a low impregnation rate, which has the advantages of preventing clothing from becoming wet with the impregnating liquid and preventing hands from becoming stained with the impregnating liquid when handling the sheet.

[0056] 1(a) and (b) show one embodiment of the coating sheet of the present invention and its method of use. The coating sheet 10A of the embodiment shown in Fig. 1(a) is rectangular with a longitudinal direction X and a transverse direction Y perpendicular to the longitudinal direction X. The coating sheet 10A has a pair of opposing long sides 11, 11 and a pair of opposing short sides 12, 12. A pair of linear slits 13, 13 are formed in the covering sheet 10A. Each slit 13 penetrates the covering sheet 10A in the thickness direction. Each slit 13 extends along the longitudinal direction X and is formed parallel to the short sides 12 of the covering sheet 10A. Each slit 13 is positioned at a predetermined distance from the short sides 12 in the transverse direction Y. The distance between the slit 13 and the short sides 12 is the same for both slits 13. The lengths of both slits 13 along the vertical direction X are the same. When viewed along the vertical direction X, both slits 13 are formed at the same positions.

[0057] The coating sheet 10A of this embodiment is worn on a person's upper body to cover the skin. Specifically, the region of the coating sheet 10A between the slits 13 and the short sides 12 becomes the front body sections 14, 14 when worn. The region between the pair of slits 13, 13 becomes the back body section 15 when worn. When the coating sheet 10A is worn on a person's upper body, the arms are inserted through the slits 13 so that the front body sections 14, 14 are positioned toward the wearer's chest and the back body section 15 is positioned toward the wearer's back, as shown in Fig. 1(b). In this case, the first side of the coating sheet 10A faces the wearer's skin, and the second side faces outward. By wearing the coating sheet 10A in this manner, various effects, such as a cooling effect, a moisturizing effect, or a skin quality improving effect, are achieved depending on the type of impregnating liquid impregnated in the coating sheet 10A. The coating sheet 10A may be used as is in the state shown in Fig. 1(b), or may be worn in the state shown in Fig. 1(b) with clothing such as underwear worn over the coating sheet 10A. As described above, the coating sheet 10A is designed to prevent the impregnating liquid from seeping out toward the second surface, so clothing that comes into contact with the coating sheet 10A is less likely to get wet.

[0058] 1(b), the distance between the pair of slits 13 is preferably approximately the width of a person's shoulders, and the length of each slit 13 is preferably greater than the circumference of a person's upper arm.

[0059] Figures 2(a) and (b) and Figures 3(a) and (b) show another embodiment of the application sheet of the present invention and its method of use. With regard to the embodiments shown in Figures 2(a) and (b) and Figures 3(a) and (b), the explanation of the embodiment shown in Figures 1(a) and (b) above applies as appropriate unless otherwise specified. In Figures 2(a) and (b) and Figures 3(a) and (b), the same components as those in Figures 1(a) and (b) are designated by the same reference numerals.

[0060] The coating sheet 10B of the embodiment shown in FIG. 2(a) has a pair of opposing long sides 11a, 11b and a pair of opposing short sides 12, 12. A single linear slit 13 is formed in the coating sheet 10B. The slit 13 penetrates the thickness direction of the coating sheet 10B. The slit 13 extends along the horizontal direction Y and is parallel to the long sides 11a, 11b of the coating sheet 10B. The slit 13 is located a predetermined distance in the vertical direction X from the two long sides 11a, 11b. Specifically, the slit 13 is biased toward one of the long sides 11a from a position that divides the coating sheet 10B into upper and lower halves in the vertical direction X.

[0061] The coating sheet 10B of this embodiment is worn on a person's upper body to cover the skin. Specifically, the region of the coating sheet 10B between the slit 13 and the long side 11a located closest to the slit 13 becomes the front body section 14 when worn. The region of the coating sheet 10B between the slit 13 and the long side 11b located farther from the slit 13 becomes the back body section 15 when worn. When the covering sheet 10B is worn on a person's upper body, the head is inserted through the slit 13 so that the front body 14 is positioned on the chest side of the wearer and the back body 15 is positioned on the back side of the wearer, as shown in Fig. 2(b). From the viewpoint of having the back body 15 cover the entire back side of the wearer, it is preferable that the length of the long sides 11a, 11b of the covering sheet 10B be approximately the width of a person's shoulders.

[0062] From the viewpoint of easily achieving the wearing state shown in FIG. 2(b), it is preferable that the length of the slit 13 is greater than the circumference of the human head.

[0063] The coating sheet 10C of the embodiment shown in Fig. 3(a) has a pair of opposing long sides 11a, 11b and a pair of opposing short sides 12, 12. A pair of slits 13, 13 is formed in the coating sheet 10C. Each slit 13 penetrates the coating sheet 10C in the thickness direction. Each slit 13 is formed symmetrically with respect to a line that bisects the coating sheet 10C into left and right equal parts in the horizontal direction Y.

[0064] Each slit 13 is composed of three linear portions: a first slit portion 13a, a second slit portion 13b, and a third slit portion 13c. The first slit portion 13a and the third slit portion 13c are formed parallel to the short sides 12 of the coating sheet 10C. The third slit portion 13c is located inward in the lateral direction Y from the first slit portion 13a. The second slit portions 13b are formed parallel to the long sides 13 of the covering sheet 10C.

[0065] One end 131a of the first slit portion 13a is located on one long side 11a, and the other end 132a of the first slit portion 13a is located at a distance in the vertical direction X from the other long side 11b. One end 131e of the third slit portion 13c is located at a distance from one long side 11a along the vertical direction X. The other end 132c of the third slit portion 13c is also located at a distance from the other long side 11b along the vertical direction X. The end 132c of the third slit portion 13c and the end 132a of the first slit portion 13a described above are the same distance from the long side 11b. The second slit portion 13b connects the end 132a and the end 132c, and therefore the second slit portion 13b is parallel to the long side 11b.

[0066] With each slit 13 configured as described above, the covering sheet 10C is formed with a pair of first connecting portions 16 and a pair of second connecting portions 17 extending along the longitudinal direction X. The first connecting portions 16 and the second connecting portions 17 each have a narrow, rectangular shape with a predetermined width. The second connecting portions 17 are located inward of the first connecting portions 16 in the transverse direction Y. One end of the first connecting portion 16 in the longitudinal direction X, specifically the end on the long side 11a side, is a free end, and the other end in the longitudinal direction X, specifically the end on the long side 11b side, is a fixed end. On the other hand, one end of the second connecting portion 17 in the longitudinal direction X, specifically the end on the long side 11b side, is a free end, and the other end in the longitudinal direction X, specifically the end on the long side 11a side, is a fixed end.

[0067] The coating sheet 10C of this embodiment is worn on a person's upper body to cover the skin. Specifically, the region of the coating sheet 10C between the pair of third slit portions 13c becomes the back body portion 15 when worn. When the covering sheet 10C is worn on a person's upper body, the covering sheet 10C is worn so that the back panel 15 is positioned on the wearer's back, as shown in Fig. 3(b). The first connecting parts 16 are then placed from above the wearer's shoulders toward the chest, and the second connecting parts 17 are placed from the wearer's armpits toward the chest. The first connecting parts 16 and the second connecting parts 17, which are placed on the chest side of the wearer, are then connected by tying them together.

[0068] Although the present invention has been described above based on its preferred embodiments, the present invention is not limited to these embodiments. For example, the coating sheet of the present invention can be used to cool human skin as one example of its use, but the target to be cooled is not limited to human skin and can also be other target surfaces. Furthermore, the coating sheet of the present invention is not limited to being used as a cooling sheet to cool target surfaces, but can also be used to cover target surfaces for purposes such as face masks (whitening, rough skin, moisturizing, anti-wrinkle), compresses, water absorption, oil absorption, and cleaning of hard surfaces.

[0069] Furthermore, when the covering sheet of the present invention is worn on the human body, it may be worn in a manner other than that shown in Figures 1 to 3. For example, the covering sheet may be wrapped around the wearer's body so that it passes under the armpits, or may be draped over the wearer's shoulders. Furthermore, instead of attaching the covering sheet to the wearer's body, a method of sandwiching and fixing the covering sheet between the wearer's body and clothing such as underwear may be employed. [Example]

[0070] The present invention will be described in more detail below with reference to examples. However, the scope of the present invention is not limited to such examples. Unless otherwise specified, "%" means "% by mass."

[0071] Examples 1 to 35 The constituent fibers of the first fiber layer including the first side and the constituent fibers of the second fiber layer including the second side were shown in Tables 1 and 2 below, and the compositions shown in the tables were used to produce base sheets by the spunlace method. The obtained substrate sheet was impregnated with an impregnation solution having the composition shown in Tables 1 to 4 at the impregnation rate shown in the same tables to produce a coating sheet.

[0072] Example 36 A meltblown nonwoven fabric made of polypropylene fibers (MPEA04 manufactured by Mitsui Chemicals, Inc.) was used as the first fiber layer, and a web of fibers shown in Table 5 was used as the second fiber layer. The first and second fiber layers were laminated to obtain a laminate, which was then hydroentangled by the spunlace method to obtain a base sheet. Thereafter, a coating sheet was obtained in the same manner as in Example 1.

[0073] Comparative Example 1 In this comparative example, there was no difference in the impregnation rate of the impregnation liquid between the first fiber layer and the second fiber layer. The fibers constituting the first fiber layer including the first side and the second fiber layer including the second side were shown in Table 6 below, and the fibers were used in the compositions shown in the same table to produce a base sheet by the spunlace method. The obtained substrate sheet was impregnated with an impregnation solution having the composition shown in Table 6 at the impregnation rate shown in the same table to produce a coating sheet.

[0074] Comparative Example 2 This comparative example is an example in which a water-soluble polymer is contained in the impregnation liquid. The coating sheet was impregnated with an impregnation solution having the composition shown in Table 6 at the impregnation rate shown in the same table. Except for this, the coating sheet was produced in the same manner as in Example 1.

[0075] Comparative Examples 3 and 4 These comparative examples are examples in which the amount of water-soluble polymer contained in the impregnation liquid was either too small (Comparative Example 3) or too large (Comparative Example 4). The coating sheet was impregnated with an impregnation solution having the composition shown in Table 6 at the impregnation rate shown in the same table. Except for this, the coating sheet was produced in the same manner as in Example 1.

[0076] Comparative Example 5 This comparative example is an example in which a substrate sheet having a single layer structure is used. A base sheet was produced by the spunlace method using the constituent fibers shown in Table 3 below. A covering sheet was produced in the same manner as in Example 1 except for this.

[0077] 〔evaluation〕 The average fiber diameters D1 and D2 of the hydrophilic fibers on the first and second sides of the coating sheets obtained in the examples and comparative examples, as well as the average fiber diameter d1 on the first side and the average fiber diameter d2 on the second side, were measured using the methods described above. For the coating sheets obtained in the examples and comparative examples, the impregnation rates of the first and second fiber layers and the coating sheets themselves were measured by the following methods. Furthermore, the coating sheets obtained in the examples and comparative examples were evaluated using the following methods for the wetness of the clothes after 5 minutes, the adhesion to the skin after 30 minutes, the feel of the skin immediately after removing the coating sheet, and the feel of the coating sheet itself. The results are shown in Tables 1 to 6 below.

[0078] [Impregnation rates of the first and second fiber layers and the covering sheet] Before impregnation, the base sheet was peeled into the first and second fiber layers, and the initial masses of each were measured. The first and second fiber layers were placed back together in a storage bag, and the impregnation was performed in the bag at the impregnation rate shown in each table. The base sheet was then pressed with a 1 kg roller to ensure that the impregnation liquid was distributed throughout the base sheet, yielding a coating sheet. After leaving the coating sheet with the first side facing downward for 12 hours or more, the masses of the first fiber layer and the second fiber layer were measured, and the impregnation rates of the first fiber layer and the second fiber layer were calculated using the following formula (1). Impregnation rate = (mass of nonwoven fabric after impregnation - mass of nonwoven fabric before impregnation) / mass of nonwoven fabric before impregnation × 100(1) The impregnation rate of the coating sheet was calculated from the above formula (1) based on the mass of the base sheet before impregnation with the impregnation liquid and the mass of the coating sheet impregnated with the impregnation liquid.

[0079] [Wetness of clothes after 5 minutes, adhesion to skin after 30 minutes, feel of skin and feel of the covering sheet immediately after removing it] Sensory evaluation was carried out by five expert monitors who were selected as expert monitors because they use the sheet formulations on a daily basis and have sufficient training in sensory evaluation using standard products. In an environment of 27°C, the inside of the forearm of the expert monitor was covered with the covering sheets of the Examples and Comparative Examples, with the first side facing the inside of the forearm. A long-sleeved cotton garment was worn over the covering sheets. Under these conditions, the expert monitor evaluated the wetness of the garment after 5 minutes, the adhesion to the skin after 30 minutes, the feel of the skin immediately after removing the nonwoven fabric, and the feel of the nonwoven fabric, according to the following criteria.

[0080] To assess the wetness of the clothes after 5 minutes, four samples (7cm x 7cm) made of the same material as the clothes worn were prepared: not wet, slightly wet, slightly wet, and wet.The wetness of the clothes was evaluated in comparison with the four samples using the following criteria. <Wetness of clothes after 5 minutes> 4: Your clothes won't get wet. 3: Clothes are slightly wet. 2: Clothes get slightly wet. 1: Your clothes will get wet.

[0081] To evaluate the adhesion to the skin after 30 minutes, the area where the covering sheet was applied was held horizontally on a desk for 30 minutes, and then the arm was tilted 90 degrees. If the covering sheet did not come off the arm, it was rated as "good adhesion," if it came off by up to a quarter, it was rated as "slight adhesion," if it came off by up to a half, it was rated as "slight adhesion," and if it peeled off, it was rated as "no adhesion," according to the following criteria. <Adhesion to skin after 30 minutes> 4: Close contact. 3: Somewhat tightly packed. 2: Slightly tight. 1: Not in close contact.

[0082] Regarding the feel on the skin immediately after removing the covering sheet, 30 minutes after applying the covering sheet to the skin, the feel on the skin immediately after removing the covering sheet was evaluated sensorily according to the following criteria. <Skin feel immediately after removing the covering sheet> 4: Non-sticky. 3: Slightly non-sticky. 2: Slightly non-sticky. 1: Sticky.

[0083] The feel of the covering sheet was evaluated when it was applied to the arm. When applied to the skin, it was rated as "good" if it felt very soft, "fairly good" if it felt soft, "slightly good" if it felt slightly soft, and "bad" if it felt hard. The evaluation was based on the following criteria. Four types of nonwoven fabric (7cm x 7cm) with a feel appropriate for each category were prepared for evaluation, and the feel was checked and evaluated. <The feel of the covering sheet> 4:Good. 3: Fairly good. 2: Slightly better. 1: Bad.

[0084] For each of the above evaluations, the average value was calculated from the evaluation values of the five expert monitors, and this average value was converted into a score from A to E as follows. A: 3.5 or more ~ 4.0 or less B: 3.0 or more to less than 3.5 C: 2.6 or more to less than 3.0 D: 1.6 or more to less than 2.6 E: 1.0 or more to less than 1.6

[0085] [Table 1]

[0086] [Table 2]

[0087] [Table 3]

[0088] [Table 4]

[0089] [Table 5]

[0090] [Table 6]

[0091] As is clear from the results shown in Tables 1 to 6, the coating sheets obtained in each example prevent clothing from getting wet even when worn with the body covered. It is also clear that the coating sheet maintains its tight fit around the body. [Explanation of symbols]

[0092] 10A, 10B, 10C Covering sheet 11, 11a, 11b long side 12 Short Side 13 Slit 14 Front 15 Back

Claims

1. a first surface and a second surface located opposite the first surface; The first surface is brought into contact with a target surface to coat the target surface; A coating sheet impregnated with an impregnation liquid, the impregnation rate of the first fiber layer including the first surface is higher than the impregnation rate of the second fiber layer including the second surface by 50% by mass or more; the impregnation liquid contains water and a water-soluble polymer, The impregnation liquid has a water content of 60% by mass or more and 99% by mass or less, and a water-soluble polymer content of 0.0025% by mass or more and 0.8% by mass or less.

2. 2. The coating sheet according to claim 1, wherein the viscosity of the impregnation liquid is 1500 mPa·s or less at 25°C.

3. The application sheet according to claim 1 , wherein the water-soluble polymer is a thickening agent.

4. The application sheet according to claim 3 , wherein the water-soluble polymer is at least one selected from the group consisting of acrylic acid-based polymers, polysaccharides, and cellulose or derivatives thereof.

5. The coating sheet according to claim 1 , wherein the average fiber diameter of the fibers on the first surface of the first fiber layer is smaller than the average fiber diameter of the fibers on the second surface of the second fiber layer.

6. Basis weight B of the first fiber layer １ Basis weight B of the second fiber layer ２ B is the ratio of ２ / B １ The coating sheet according to claim 1, wherein the value of is 0.2 or more and 2.0 or less.

7. The coating sheet according to claim 1 or 2, wherein the impregnation rate of the first fiber layer is 200% by mass or more.

8. The coating sheet according to claim 1 or 2, wherein the impregnation rate is 700% by mass or less.

9. The coating sheet according to claim 1 or 2, wherein the average fiber diameter of the fibers constituting the first fiber layer is 11.9 μm or less on the first surface.

10. A method for using a covering sheet, the covering sheet having a first surface and a second surface opposite to the first surface and impregnated with an impregnation liquid, for covering a target surface with the first surface of the covering sheet, The covering sheet is the impregnation rate of the first fiber layer is 50% by mass or more higher than the impregnation rate of the second fiber layer; the impregnation liquid contains water and a water-soluble polymer, The method for using a coating sheet, wherein the content of the water in the impregnation liquid is 60% by mass or more and 99% by mass or less, and the content of the water-soluble polymer in the impregnation liquid is 0.0025% by mass or more and 0.8% by mass or less.

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