JP4545182B2 - Cleaning sheet - Google Patents

Description

  The present invention relates to a wet-type cleaning sheet for personal use, and more particularly to a cleaning sheet with good foaming and good skin feel.

  The present applicant has previously proposed a three-dimensional sheet material made of a fiber material and having many irregularities on one surface (see Patent Document 1). This three-dimensional sheet material has a basic structure consisting of a laminate of two fiber layers, and one of the fiber layers contains heat-shrinkable fibers. Then, the other fiber layer is raised by the shrinkage of the heat-shrinkable fiber to form irregularities.

  This three-dimensional sheet material is suitably used as a constituent member of a disposable article that is discarded once or several times. For example, it is used as a component of a disposable absorbent article such as a disposable absorbent article such as a sanitary napkin or a disposable diaper, a cleaning wiper or an interpersonal wiper.

  However, various performances required for wipers and the like are becoming stricter day by day, and in particular, wet wipers for personal use are required to further enhance the touch to the skin and fine foaming of the cleaning agent.

JP 2002-187228 A

  Accordingly, an object of the present invention is to provide a wet-type cleaning sheet for personal use that has good foaming and good skin feel.

In the present invention, a first fiber layer that is on the skin-facing side in use and a second fiber layer disposed on one surface of the first fiber layer are laminated, and both layers are partially bonded at a number of bonding portions. It is integrated in the thickness direction, and the first fiber layer protrudes in a convex shape due to thermal contraction of the second fiber layer between the joints, and a large number of irregularities are formed on the surface on the first fiber layer side. It is a cleaning sheet for humans, wherein a base material sheet is impregnated with a cleaning agent containing a surfactant,
The fine fiber of the first fiber layer is smaller than the fine fiber of the second fiber layer and the fine fiber of the first fiber layer is 0.5 to 3.3 dtex, and the second fiber layer The object is achieved by providing a cleaning sheet having a fineness of 2.2 to 11 dtex.

  The cleaning sheet of the present invention has good foaming, and the foam is fine and creamy. In addition, the cleaning sheet of the present invention has a high level of dirt scraping and good dirt removal. Furthermore, the cleaning sheet of the present invention has a good feel against the skin.

  The present invention will be described below based on preferred embodiments with reference to the drawings. FIG. 1 shows a perspective view of an embodiment of a substrate sheet in the cleaning sheet of the present invention, and FIG. 2 shows a cross section taken along line II-II in FIG. A base sheet 10 shown in FIG. 1 has a two-layer structure of a first fiber layer 1 and a second fiber layer 2 arranged on one surface of the first fiber layer 1. The first fiber layer 1 is the skin facing side when the cleaning sheet of the present invention is used. The first fiber layer 1 and the second fiber layer 2 are each composed of a fiber assembly. The second fiber layer 2 is composed of an aggregate of fibers of a different type and / or blend from the fibers constituting the first fiber layer 1. The 1st fiber layer 1 and the 2nd fiber layer 2 are mutually laminated, and are joined partially by many joined parts 3 of a predetermined pattern.

  As shown in FIG. 3, the joint portions 3 in the present embodiment are arranged in a so-called staggered pattern. Each of the joint portions 3 is formed discontinuously in a circular shape in plan view. The joint portion 3 is consolidated and has a smaller thickness and a higher density than other portions of the base sheet 10. The joining portion 3 is formed by various joining means such as heat embossing, ultrasonic embossing, and adhesion using an adhesive. The joint 3 in the present embodiment is circular, but the shape of the joint 3 may be an ellipse, a triangle, a rectangle, or a combination thereof in addition to a circle. Moreover, you may form the junction part 3 in the continuous shape, for example, linear shapes, such as a straight line and a curve, a grid | lattice shape.

  In the first fiber layer 1, portions other than the joint portion 3 joined to the second fiber layer 2 protrude in a convex shape. That is, as shown in FIGS. 1 and 2, the portion of the first fiber layer 1 located between the joint portions 3 (specifically, the rectangular portion having the joint portions 3 at the four corners) is the second fiber layer 2. It protrudes in a convex shape (dome shape) by heat shrinkage, and thereby a large number of convex portions 4 are formed on the first fiber layer side of the base sheet 10. The inside of each convex portion 4 is filled with fibers constituting the first fiber layer 1. The shape of the convex part 4 is mainly determined by the form of the fiber assembly constituting the first fiber layer 1 and the pattern of the joint part 3. A concave portion 5 is formed between the convex portions 4. The joint 3 described above is located at the bottom of the recess 5. On the other hand, on the second fiber layer 2 side, a substantially flat surface is maintained between the joint portions 3. When viewed as the base material sheet 10 as a whole, the surface on the second fiber layer 2 side is substantially flat, and a large number of irregularities are formed on the surface on the first fiber layer 1 side. Due to the base sheet 10 having such a three-dimensional structure, in the cleaning sheet of the present invention in which the sheet 10 is impregnated with a cleaning agent, a large amount of air is retained therein. And foaming is good, and creamy foam is produced. Moreover, the scraping property of dirt when the skin is wiped is improved. Furthermore, since the convex part 4 makes point contact with skin, a feeling becomes favorable. Due to the cushioning property resulting from the formation of irregularities, the feel and foaming are further improved. In addition, since stretchability is imparted to the base sheet 10 by using latent crimpable fibers, which will be described later, the cleaning sheet of the present invention has good hand fit.

  In the base material sheet 10, the fineness of the constituent fibers of the first fiber layer 1 is smaller than the fineness of the constituent fibers of the second fiber layer 2. Thereby, the feel when the base sheet 10 is impregnated with the cleaning agent to wipe the skin is further improved. Further, due to the elasticity generated by the second fiber layer 2 made of thick fibers, the foaming when the cleaning sheet of the present invention is squeezed by hand becomes better and the foaming becomes finer. In order to make these effects more remarkable, in the present invention, fine bubbles are formed by using fine fibers as the constituent fibers of the first fiber layer 1. Specifically, those having a fineness of 0.5 to 3.3 dtex are used, preferably those having a fineness of 1.1 to 2.2 dtex. Furthermore, elasticity is imparted to the base material sheet 10 by using fibers having a large fineness as constituent fibers of the second fiber layer 2. Specifically, those having a fineness of 2.2 to 11 dtex are used, preferably those having a fineness of 2.2 to 5.5 dtex. In this case, the fineness of the constituent fibers of the second fiber layer 2 is preferably 1.1 to 22 times, particularly 1.2 to 5 times larger than the fineness of the constituent fibers of the first fiber layer 1.

The feel and foaming of the cleaning sheet of the present invention are also related to the basis weight of the base sheet 10 and the fiber layers 1 and 2. Specifically, the basis weight of the first fiber layer 1 is from the viewpoint of imparting a sufficient bulkiness to the base sheet 10, increasing the compressibility and flexibility, and further improving the feel and foaming. It is preferable that it is 10-60 g / m < ² >, especially 15-45 g / m < ² >, and it is preferable that the basic weight of the 2nd fiber layer 2 is 10-80 g / m < ² >, especially 15-65 g / m < ² >. Furthermore, it is preferable that the basic weight of the base material sheet 10 is 20 to 140 g / m ² , particularly 30 to 110 g / m ² .

  In addition to the fineness of the constituent fibers and the basis weight of each fiber layer, the bulk softness per unit thickness of the base sheet 10 in a state impregnated with the cleaning agent is also related to the feel and foaming of the cleaning sheet of the present invention. . Specifically, the bulk softness per unit thickness of the substrate sheet 10 in the state impregnated with the cleaning agent is preferably 0.03 to 0.49 N / mm, more preferably 0.05 to 0.35 N / mm. When it is, a touch and foaming become still better. The bulk softness per unit thickness preferably satisfies the above range in at least one of the flow direction and the width direction of the base sheet 10, and particularly preferably satisfies the above range in any direction. In order to set the bulk softness per unit thickness of the base sheet 10 in the state impregnated with the cleaning agent within the above range, for example, the basis weight of the first fiber layer 1 and the second fiber layer 2 is adjusted, What is necessary is just to adjust the number and area of a junction part.

  The bulk softness per unit thickness of the substrate sheet 10 in the state impregnated with the cleaning agent is measured by the following method. Regarding the flow direction, a measurement piece having a length of 30 mm in the flow direction (MD) and a length of 150 mm in the width direction (CD) is cut out from the cleaning sheet. As shown in FIG. 4, the measurement piece is formed in a columnar shape so that the width direction (CD) of the measurement piece is the circumferential direction. In order to maintain the cylindrical shape, the measurement piece is fixed with the stapler S. At this time, the circumference of the cylinder is set to 140 mm. The cylinder is compressed in the height direction (that is, the flow direction MD) (compression speed: 10 mm / min). The maximum stress observed at that time is divided by the thickness of the measurement piece, and the value is taken as the value of the bulk softness in the flow direction. The thickness of the measurement piece is a thickness t described later. The bulk softness in the width direction of the base sheet 10 is obtained by measuring the flow direction and the width direction in the above-described measurement method.

As described above, the good feel and foaming of the cleaning sheet according to the present invention are attributed to the three-dimensional shape of the base sheet 10. From this viewpoint, the thickness t ₁ of the first fiber layer of the base sheet 10 in the state impregnated with the cleaning agent is 0.1 to 5 mm, particularly 0.1 to 3. mm, and the thickness t ₂ of the second fiber layer is preferably 0.2 to 3 mm, particularly 0.3 to 2 mm. The total thickness (thickness under no load) is represented by t = t ₁ + t ₂ , and the value is preferably 0.3 to 8 mm, particularly preferably 0.4 to 6 mm.

The thickness t ₂ of the thickness t ₁ and a second fibrous layer of the first layer fibers are measured as follows. In a measurement environment at a temperature of 23 ° C. and a humidity of 65% RH, a measurement piece having a length and width of 30 mm × 30 mm is cut out from the cleaning sheet. And it is a cut surface by the line which passes through the junction part 3 (refer FIG. 2) substantially parallel to the vertical direction [The fiber orientation direction (flow direction at the time of nonwoven fabric manufacture) of the nonwoven fabric (fiber assembly) which comprises a 1st fiber layer]]. make. An enlarged photograph of this cross section is obtained with a high scope (Olympus, SZH10). The maximum thickness of the first fiber layer portion is obtained by adjusting the scale of the enlarged photograph, and this is defined as the thickness (t ₁ ) of the first fiber layer, and the second fiber layer portion at the maximum thickness measurement site of the first fiber layer. Is measured, and this is defined as the thickness (t ₂ ) of the second fiber layer. That is, the thicknesses of the first fiber layer and the second fiber layer are measured along the same straight line extending in the sheet thickness direction (see FIG. 2). The total thickness t is calculated from the sum of t ₁ and t ₂ .

In the base sheet 10, it first fiber density of the fiber layer 1 (d ₁₎ and the second fiber density of the fiber layer 2 (d ₂₎ are each 1 to 50 kg / m ³ and 30~200kg / m ³ Is preferable from the viewpoint of impregnation of the cleaning agent, foaming, and fineness of the foam. The fiber density of the first fiber layer and the second fiber layer is measured as follows. In a measurement environment at a temperature of 23 ° C. and a humidity of 65% RH, a measurement piece having a length and width of 30 mm × 30 mm is cut out from the substrate sheet 10. The fiber density of the first fiber layer is substantially parallel to the longitudinal direction of the measurement piece [the fiber orientation direction of the nonwoven fabric (fiber assembly) constituting the first fiber layer (flow direction during the production of the nonwoven fabric)] and the joint portion. Make a cut surface perpendicular to the thickness direction on the line passing through. From this cross section, the thickness t ₁ of the first fiber layer is measured in the same manner as in the thickness measurement described above. Next, the area (a ₁ × b ₁ ) of the first fiber layer measured in advance before shrinkage (before joining of the first fiber layer and the second fiber layer) and the first fiber layer are joined to the second fiber layer to shrink. From the area (a ₂ × b ₂ ) of the first fiber layer measured after the treatment (see FIG. 5), the formula [shrinkage area ratio A = (a ₁ × b ₁ −a ₂ × b ₂ ) ÷ (a ₁ × b ₁ )] to obtain the shrinkage area ratio (A) of the measurement piece, and further measured in advance before the shrinkage area ratio (A) thus obtained and before shrinkage (before joining the first fiber layer and the second fiber layer). From the basis weight (P1) of the first fiber layer, the basis weight (P2 of the first fiber layer) is calculated according to the formula [basis weight P2 of the first fiber layer = P1 × 100 / (100−A) (g / m ² )]. ) Then, the fiber density d ₁ of the first fiber layer is obtained from the formula [d ₁ = P2 / t ₁ (kg / m ³ )]. The fiber density of the second fiber layer 2 can be determined in the same manner as the measurement of the fiber density of the first fiber layer. At this time, the thickness t ₂ of the second fiber layer is measured in the same manner as in the thickness measurement described above, and the fiber density d ₂ is calculated using this value.

  As the fibers constituting the first fiber layer 1, fibers made of a thermoplastic polymer material are preferably used. Examples of the thermoplastic polymer material include polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate, and polyamides. A core-sheath type composite fiber or a side-by-side type composite fiber made of a combination of these thermoplastic polymer materials can also be used. Moreover, as a fiber which comprises the 1st fiber layer 1, what does not have heat shrinkability substantially or does not heat-shrink below the heat shrink temperature of the fiber which comprises the 2nd fiber layer 2 mentioned later is used.

  As the fiber constituting the second fiber layer 2, one made of a thermoplastic polymer material and having heat shrinkability is used. It is also preferred that the fiber exhibits an elastomeric behavior. Examples of such fibers include latently crimpable fibers. The latent crimpable fiber is a fiber that can be handled in the same manner as a conventional nonwoven fabric fiber before being heated, and has a property that a helical crimp is developed and contracted by heating at a predetermined temperature. is there. By using latent crimpable fibers, both heat shrinkability and elastomeric behavior can be developed simultaneously. As a result, the base material sheet 10 comes to exhibit elasticity. The latent crimpable fiber includes, for example, an eccentric core-sheath type composite fiber or a side-by-side type composite fiber containing two types of thermoplastic polymer materials having different shrinkage rates as components. Examples thereof include those described in JP-A-9-296325 and Japanese Patent No. 2759331.

  The first fiber layer 1 and / or the second layer fiber 2 is mixed with fibers other than those described above, for example, water-absorbing fibers such as rayon, cotton, hydrophilized acrylic fiber, etc. It is preferable because the impregnation retention and the sustained release property are improved. In addition, the foaming property is also improved, the bubbles can be continuously generated, and the dirt can be effectively removed. The water-absorbing fibers are preferably contained in an amount of 5 to 90% by weight, particularly 10 to 70% by weight, based on the weight of each layer, from the viewpoint of impregnation retention of the cleaning agent and prevention of sheet sag.

  As the form of the aggregate of the fibers constituting the first fiber layer 1, for example, a web formed by a card method, a non-woven fabric formed by a thermal fusion method, a non-woven fabric formed by a hydroentanglement method, or formed by a needle punch method Nonwoven fabric formed by a solvent bonding method, nonwoven fabric formed by a spunbond method, nonwoven fabric formed by a melt blown method, or knitted fabric. When the first fiber layer 1 is in the form of a web formed by a card method, the base sheet 10 is formed with a bulky convex portion filled with fibers constituting the web, and the fibers Is oriented along the convex part. On the other hand, when the 1st fiber layer 1 is a form of a nonwoven fabric or a knitted fabric, a hollow dome-shaped convex part is formed. In particular, when the first fiber layer 1 is configured using a web formed by the card method, the first fiber layer 1 has a very sparse structure. In the case of a high viscosity cleaning agent, a large amount of cleaning agent is used. Holding is possible. Moreover, the compressive deformability when the base material sheet 10 is compressed in the thickness direction is also increased.

  The web formed by the card method is a fiber assembly in a state before being made into a nonwoven fabric. That is, a fiber assembly in which fibers are in an extremely loose entanglement state after being subjected to a post-treatment applied to a card web used for manufacturing a nonwoven fabric, for example, a heat-sealing treatment by an air-through method or a calendar method. It is the body. When using the web formed by the card | curd method for the 1st fiber layer 1, after joining the 1st fiber layer 1 and the 2nd fiber layer 2, or after making it join, the fibers in the 1st fiber layer 1 are connected. , Heat fusion or adhesion by solvent or mechanical entanglement.

  On the other hand, as the form of the aggregate of fibers constituting the second fiber layer, (1) a web including latent crimpable fibers and formed by a card method, or (2) a non-woven fabric having heat shrinkability, Non-woven fabric formed by fusing method, non-woven fabric formed by hydroentanglement method, non-woven fabric formed by needle punch method, non-woven fabric formed by solvent bonding method, non-woven fabric formed by spunbond method, formed by meldblown method The nonwoven fabric made is mentioned. Here, the non-woven fabric having heat shrinkability is a non-woven fabric having a property of shrinking by heating at a predetermined temperature.

  As a preferable method for producing the substrate sheet 10, the method described in paragraph [0042] of Patent Document 1 may be mentioned. Specifically, first, a second fiber layer made of an aggregate of fibers made of a thermoplastic polymer material and containing heat-shrinkable fibers, and a thermoplastic polymer material that does not substantially heat shrink or second. The first fiber layer made of an aggregate of fibers that does not heat-shrink at a temperature equal to or lower than the heat-shrink temperature of the fibers constituting the fiber layer is superposed, and both are partially bonded at a predetermined pattern bonding portion. In particular, it is preferable to use, as the first fiber layer, a card web formed by opening fibers using a fiber opening card machine. Next, the fibers contained in the second fiber layer are heat-treated at a temperature higher than the temperature at which heat shrinkage starts to shrink the second fiber layer, and the first fiber layer located in the closed region surrounded by the joint is convex. To form a three-dimensional solid shape.

  The cleaning agent impregnated in the base sheet 10 contains a surfactant. The impregnation amount of the cleaning agent is preferably 100 to 1500% by weight, particularly 200 to 1200% by weight based on the weight of the base sheet 10, from the viewpoint of good handleability as a personal wiper. For example, a die coater, a reverse coater, or a gravure coater can be used for impregnating the base material sheet 10 with the cleaning agent. As another method of impregnating the cleaning agent, the following method may be mentioned. That is, a coating film of a cleaning agent is formed on a flat plate such as a glass plate using a doctor blade. On the coating film, the base material sheet 10 is placed so that the surface of the first fiber layer 1 in the base material sheet 10 to be impregnated is in close contact. A roller is applied to the upper surface of the substrate sheet 10 at a constant speed so that the substrate sheet 10 and the coating film are in uniform contact with each other, and then the substrate sheet 10 is peeled off to obtain an impregnated sheet. A roller with a constant load is used as the roller. If it is insufficient, apply additional load by hand. If the load is insufficient, the base sheet 10 may not be sufficiently impregnated with the cleaning agent. If the load is excessive, the cleaning agent is pushed out of the base sheet 10, so that the target amount of the cleaning agent may be impregnated. There are cases where it is not possible. It is preferable that the roller has a long impregnation time over a plurality of times from the viewpoint that the cleaning agent can be sufficiently impregnated, and that the roller can be impregnated uniformly and foaming can be efficiently performed.

  As the surfactant contained in the cleaning agent, one or more of amphoteric surfactant, anionic surfactant, cationic surfactant and nonionic surfactant can be used in combination. The amount of the surfactant in the cleaning agent is preferably 1 to 60% by weight, particularly 2 to 40% by weight, from the viewpoints of foaming properties, cleaning properties and the like. Examples of components other than the surfactant contained in the cleaning agent include humectants, bactericides, preservatives, chelating agents, electrolytes, medicinal agents, dyes, fragrances, antioxidants, pH adjusters, and the like. The components are appropriately blended within a range not impairing the effects of the present invention.

  The cleaning sheet of the present invention is used for wiping the face, limbs and the like as a wiping wet wiper for personal use. In use, the cleaning sheet is well squeezed by hand, and the cleaning agent is sufficiently foamed. Thereafter, the second fiber layer 2 side is opposed to the hand and the first fiber layer side is opposed to the body, and a predetermined part of the body is defined. Wipe away. As another method, after impregnating the base material sheet 10 with the cleaning agent, the base material sheet 10 may be dried to remove the liquid component so that the cleaning agent does not substantially contain water. In this case, after the cleaning sheet contains water or warm water, the cleaning sheet is thoroughly squeezed by hand and the cleaning agent is sufficiently foamed, and then the first fiber layer side is opposed to the body, and a predetermined part of the body Wipe out. In such a use form, the cleaning sheet is substantially free of water and can be easily carried. Therefore, there is an advantage that even when it is difficult to obtain the cleaning agent, it can be easily foamed by adding water and thoroughly squeezing it by hand.

  In the above-described embodiment, the base sheet 10 has a two-layer structure of the first fiber layer 1 and the second fiber layer 2, but instead of this, the surface of the second fiber layer 2 (that is, exposed to the outside). The liquid-impermeable sheet may be laminated on the surface) to form a three-layer structure so that the cleaning agent does not adhere to the hand when the cleaning sheet is used.

As the liquid-impermeable sheet, a sheet that can prevent the cleaning agent impregnated in the base sheet 10 from permeating to the back side during use of the cleaning sheet is used. Specific examples of the liquid-impermeable sheet include general thermoplastic resin, polyester, polyethylene, polypropylene, polyvinyl alcohol, polyvinyl chloride, polyvinylidene chloride, ethylene-vinyl acetate copolymer, polyamide, cellophane, polyetherimide, Examples include films made of resins such as polycarbonate, polyarylate, polysulfone, polyphenylene sulfide, and polyetheretherketone. From the viewpoint of heat sealability and flexibility, partially modified products and copolymers of these resins may be used. Two or more of these resins may be used in combination, or may be combined in a laminate structure of two or more layers. Among them, a film made of an ionomer resin, a polypropylene film, a polyethylene film, and the like are preferable because of good workability, and a film made of an ionomer resin, a linear low density polyethylene film, and a stretched polypropylene film are particularly flexible, sealable, The pinhole resistance and the cosmetic base permeation-preventing property are preferable. The liquid impervious sheet has a basis weight of 5 to 100 g / m ² , particularly 10 to 80 g / m ² , which can sufficiently prevent the permeation of the detergent, and maintain the texture of the base sheet. And from the viewpoint of manufacturing cost.

  A sheet of fiber material is further laminated on the surface of the liquid-impermeable sheet (that is, the surface exposed to the outside) to form a four-layer structure, and the cleaning agent adhering to the skin after wiping is wiped off with the sheet. It may be. The sheet of fiber material comes into contact with the hand when the cleaning sheet is used, and is not impregnated with the cleaning agent. As the fiber material sheet, a sheet having a good texture is used. Such a fiber material sheet preferably has a cloth-like texture, and a nonwoven fabric, a woven fabric, a knitted fabric, a foam, a net, an apertured film, or the like is used. It is preferable to use a nonwoven fabric from the viewpoint of preventing the back of the cleaning agent, a high porosity, and a good skin feel.

When using a nonwoven fabric as a sheet of fiber material, it is preferable to use a nonwoven fabric produced by an air-through method, a resin bond method, a spunlace method, or an airlaid method because of its low density and good feel. The basis weight is preferably 10 to ²⁰⁰ g / m ² , particularly 15 to 150 g / m ² , from the viewpoint of good touch to the skin and prevention of the backside of the cleaning agent. As the constituent fiber, either a hydrophilic fiber or a hydrophobic fiber can be used. Examples include polyester fibers such as polyethylene terephthalate, acrylic fibers such as polyacrylonitrile, polyamide fibers, polyolefin fibers of polypropylene and polyethylene, polyurethane fibers, polyvinyl alcohol fibers, polyfluoroethylene fibers, etc. Synthetic fibers; natural fibers such as cotton, hemp, hair, silk; regenerated fibers such as rayon, polynosic, cupra, etc .; semi-synthetic fibers such as acetate; Moreover, the composite fiber which combined 2 or more types of these materials can also be used. These fibers may have an irregular cross section. In consideration of the surface tension of the cleaning agent, the wettability of the fibers, and the capillary diameter of the fiber structure, a plurality of types of the fibers may be used in combination. The fineness of the constituent fibers is preferably 0.011 to 16.5 dtex, and particularly preferably 0.11 to 13.2 dtex from the viewpoint of good feeling and prevention of slipping. Most preferably, all the fibers constituting the nonwoven fabric have a fineness in the above range, but 30% by weight or more, particularly 50% by weight or more of the entire nonwoven fabric may have a fineness in the above range. The thickness of the nonwoven fabric is preferably 0.3 to 5 mm under a load of 3.7 g / cm ² , and more preferably 0.3 to 2.0 mm from the viewpoint of portability.

  As a method for producing a substrate sheet having a three-layer structure or a four-layer structure, for example, an extrusion lamination method (sandwich lamination method) is preferable. This method has the advantage that peeling between the sheets hardly occurs and pinholes are hardly generated in the liquid-impermeable sheet. The occurrence of pinholes causes the cleaning agent to permeate into the fiber material sheet during use of the cleaning sheet.

  In this invention, a 1st fiber layer may be laminated | stacked on each surface of a 2nd fiber layer, and an unevenness | corrugation may be formed on both surfaces of a base material sheet. As another form, the second fiber layer 2 of another base material sheet 10 is overlapped with the second fiber layer 2 of the base material sheet 10, and both are bonded in a predetermined pattern to form a glove shape, which is impregnated with a cleaning agent. You may let them. In this embodiment, foaming occurs when the hand is put in the hand, so that the hand can be easily washed as it is. In this case, the fiber diameter, basis weight, fiber composition, and bonding pattern of the two first fiber layers may be changed, and one surface may be impregnated with a cleaning agent and then dried. In this embodiment, water or lukewarm water may be included and then thoroughly rinsed and washed on one side, and the foam may be wiped off on the other side. Thus, in the cleaning sheet of the present invention, since the thermoplastic polymer material is used for the second fiber layer 2, a plurality of substrate sheets can be joined and cut in a free pattern. Accordingly, a free form such as a tubular shape or a glove shape that cannot be achieved by a conventional cleaning sheet mainly composed of hydrophilic fibers is possible.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the scope of the present invention is not limited to such examples.

[Example 1]
(1) Manufacture of first fiber layer A card web having a basis weight of 10 g / m ² by a card method using a core-sheath type composite fiber NBF (H) [trade name, 1.1 dtex × 51 mm] manufactured by Daiwa Boseki Co., Ltd. as a raw material Was used as the first fiber layer. The core-sheath type composite fiber has polyethylene terephthalate as a core component and polyethylene as a sheath component.

(2) Manufacture of the second fiber layer A card having a basis weight of 20 g / m ² by a card method using a latent spiral crimped fiber [CPP fiber (trade name), 2.2 dtex × 51 mm] manufactured by Daiwa Spinning Co., Ltd. as a raw material A web was produced and used as the second fiber layer.

(3) Production of substrate sheet The first fiber layer and the second fiber layer were superposed and partially joined by an ultrasonic embossing method. The joint part was circular, and the pattern shown in FIG. 3 was formed as a whole. After both are joined, they are heat-dried at 130 ° C. ± 10 ° C. for about 1 to 10 minutes to crimp the latent crimped fibers of the second fiber layer to shrink the second fiber layer and the first fibers between the joints The layer was protruded in a convex shape, and a base sheet having a large number of convex portions shown in FIGS. 1 and 2 was produced. The inside of the portion where the first fiber layer protruded in a convex shape was filled with fibers as shown in FIG.

(4) Production of Cleaning Sheet The obtained base sheet was cut into 100 mm × 100 mm, and impregnated with a cleaning agent (trade name: Kao Hand Wash PSa). The impregnation amount was 580% by weight based on the weight of the base sheet.

[Examples 2 and 3]
Rayon is blended in each of the first fiber layer and / or the second fiber layer, and the fineness shown in Table 1 as the core-sheath type composite fiber and the latent spiral crimp fiber contained in the first fiber layer and the second fiber layer. A cleaning sheet was obtained in the same manner as in Example 1 except that the basis weight of each fiber layer and substrate sheet was set to the value shown in the same table. In Example 2, the amount of rayon in the first fiber layer was 40% by weight, and the amount of rayon in the second fiber layer was 0% by weight. In Example 3, the amount of rayon in the first fiber layer was 15% by weight, and the amount of rayon in the second fiber layer was 15% by weight.

    [Comparative Examples 1 to 3] The fiber contained in the first fiber layer and the second fiber layer was used as shown in Table 1, except that the basis weight of each fiber layer and the base sheet was set to the value shown in the same table. A cleaning sheet was obtained in the same manner as in Example 1.

[Performance evaluation]
With respect to the cleaning sheets obtained in the examples and comparative examples, the bulk softness in the flow direction per unit thickness was measured by the method described above. Moreover, the touch at the time of wiping, the degree of dirt removal, the amount of foaming and the fineness of the foam were evaluated by the following methods. The results are shown in Table 1.

[Feel when wiping]
Ten professional panelists wiped their faces, limbs, and the like with the cleaning sheets obtained in the examples and comparative examples, and sensoryly evaluated the touch. The number of persons judged to be unpleasant was rated as 1 or less, ◎, 2 as ◯, 3 or 4 as ◯, 5 or 6 as △, and 7 or more as X.

[Degree of dirt removal]
A UV agent (Nivea Sun Protect CREAM Mild) is applied to artificial leather (Idemitsu Technofine SUPPLALE-PBZ12002 Color 4 Grade 1) with a doctor blade to a thickness of 100 microns and left for 3 hours. The UV agent attached to the artificial leather is wiped off 5 times with the cleaning sheets obtained in Examples and Comparative Examples. The artificial leather is then measured with a color difference meter, and the difference from the initial color difference is defined as the washing rate. A cleaning rate of 70% or more was evaluated as ◯, less than 70% as 60% or more as △, less than 60% as 50% or more as Δ, and less than 50% as ×.

[Foaming amount]
To 20 g of the cleaning agent, 180 g of tap water is added and mixed to obtain an aqueous solution. The substrate sheet of the cleaning sheet is cut into 20 cm × 15 cm, immersed in the aqueous solution, and after 30 seconds, the sheet is folded and foamed 30 times, and the foamed foam is collected and weighed. The amount of foaming was evaluated from the foam weight according to the following criteria.
○: 13 g or more ○ △: 10 g or more and less than 13 g Δ: 7 g or more and less than 10 g ×: less than 7 g

[Foam fineness]
In the same manner as the measurement of the amount of foaming, the foamed foam is collected and sandwiched between acrylic plates. Under this condition, the bubble diameter is measured with a microscope. The average of N = 20 was made into the bubble diameter, and the following references | standards evaluated.
○: Bubble diameter is 0.95 mm or less ○ △: Bubble diameter is 0.95 mm or more and less than 1.2 mm Δ: Bubble diameter is 1.2 mm or more and less than 1.45 mm ×: Bubble diameter is 1.45 mm or more

    As is clear from the results shown in Table 1, it can be seen that the cleaning sheets of the respective examples (products of the present invention) have a good feel to the skin and have high dirt removal properties. Further, it can be seen that the amount of foaming is large and the foam is fine.

It is a perspective view which shows one Embodiment of the base material sheet in the washing | cleaning sheet of this invention. It is the II-II sectional view taken on the line in FIG. It is a schematic diagram which shows the pattern of the junction part in the base material sheet shown in FIG. It is explanatory drawing which shows the measuring method of bulk softness. It is explanatory drawing which shows the calculation method of shrinkage area ratio.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st fiber layer 2 2nd fiber layer 3 Joining part 4 Convex part 5 Concave part 10 Base material sheet

Claims (7)

The second fibrous layer and the first fiber layer fiber density of 1 to 50 kg / m ³ as a skin-facing side, fiber density which is disposed on one surface of said first fibrous layer is 30~200kg / m ³ at the time of use And the two layers are partially joined at a number of joints and integrated in the thickness direction, and the first fiber layer protrudes in a convex shape between the joints due to thermal contraction of the second fiber layer. In addition, a base sheet in which a large number of irregularities are formed on the surface on the first fiber layer side is a personal cleaning sheet impregnated with a cleaning agent containing a surfactant,
The fine fiber of the first fiber layer is smaller than the fine fiber of the second fiber layer and the fine fiber of the first fiber layer is 0.5 to 3.3 dtex, and the second fiber layer A cleaning sheet having a fineness of 2.2 to 11 dtex. The basis weight of the first fiber layer is 10 to 60 g / m ² , the basis weight of the second fiber layer is 10 to 80 g / m ² , and the basis weight of the entire base sheet is 20 to 140 g / m ^2. Item 5. A cleaning sheet according to Item 1.   The cleaning sheet according to claim 1 or 2, wherein the bulk softness per unit thickness is 0.03 to 0.49 N / mm.   The cleaning sheet according to any one of claims 1 to 3, wherein the first fiber layer or the second fiber layer contains 5 to 90 wt% of water-absorbing fibers based on the weight of the fiber layer.   The cleaning sheet according to any one of claims 1 to 4, wherein a liquid-impermeable sheet is laminated on the surface on the second fiber layer side.   The cleaning sheet according to claim 5, wherein a sheet of fiber material is further laminated on the surface of the liquid-impermeable sheet.   The cleaning sheet according to claim 1, wherein the cleaning agent does not substantially contain water.

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