JP2025051401A - Nonwoven laminate sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nonwoven laminate sheet for body-wiping sheets that ensures excellent heat retention and user comfort during use in a wet state.

SOLUTION: Provided is a nonwoven laminate sheet with a basis weight ranging from 100 to 300 g/m², including at least an intermediate layer comprising airlaid nonwoven fabric and surface layers bonded to both sides of the intermediate layer via an adhesive, wherein the intermediate layer contains thermally adhesive fibers and at least 62 mass% of cellulose-based fibers based on the total mass of the intermediate layer, and the intermediate layer has a greater water retention capability than the surface layers.

SELECTED DRAWING: None

COPYRIGHT: (C)2025,JPO&INPIT

Description

The present invention relates to a nonwoven fabric laminate sheet. More specifically, the present invention relates to a nonwoven fabric laminate sheet that has good water retention capacity and provides excellent heat retention and usability when used in a wet state.

A wet body-cleaning sheet is known that is impregnated with an aqueous solution. The wet body-cleaning sheet can be used to clean the bodies of hospitalized patients and residents of nursing homes who have difficulty taking a bath, and the body-cleaning sheet is preheated before use to avoid cold irritation. Generally, as described in Patent Document 1 (JP Patent Publication 2009-11702), a nonwoven fabric having a basis weight of about 25 to 100 g/m ² is rolled and packaged. However, even if the nonwoven fabric is preheated in the rolled form, it quickly cools down when it is unrolled and used.

Patent Document 2 (JP Patent Publication 2004-313557) discloses a body cleaning sheet made of a nonwoven laminate sheet using a nonwoven fabric containing a water-absorbent polymer compound to enhance heat retention after heating. The water-absorbent polymer compound absorbs an aqueous detergent and swells, and can hold a large amount of the aqueous detergent within the absorbent polymer compound, so that when heated, high heat retention is maintained by the moisture in the heated water washing detergent. However, when the water-absorbent polymer compound swells due to absorption of water, it falls off from the nonwoven laminate sheet, which is the support. For example, a surface layer is placed on both sides of the inner layer, and the nonwoven fabric containing the water-absorbent polymer compound is completely covered on both the upper and lower sides with another nonwoven fabric that serves as the surface layer, which is a manufacturing technique that requires considerable productivity degradation. In addition, if the water-absorbent polymer compound is stored for a long period of time while the aqueous detergent is absorbed in the water-absorbent polymer compound, there is a concern that the polymer compound itself will flow out, and such a body cleaning sheet does not provide sufficient heat retention and a good feel when used.

Patent document 3 (International Publication WO 2007/135862) describes a skin cleansing sheet having a web layer produced by an airlaid method that contains a specific amount of heat-adhesive fibers having a specific fineness and cellulosic pulp, but this skin cleansing sheet does not provide sufficient heat retention.

JP 2009-11702 A JP 2004-313557 A International Publication No. 2007/135862

The objective of the present invention is to provide a nonwoven fabric laminate sheet that has good water retention capacity, excellent heat retention and excellent usability when used in a wet state, and is suitable for use as a body cleansing sheet.

The above problems can be solved by the following invention.

A nonwoven fabric laminate sheet having a basis weight of 100 to 300 g/ ^m2 , comprising at least an intermediate layer containing an airlaid nonwoven fabric, and surface layers bonded to both sides of the intermediate layer via an adhesive component, wherein the intermediate layer contains a thermal adhesive fiber and 62 mass% or more of a cellulosic fiber relative to the total mass of the intermediate layer, and the water retention capacity of the intermediate layer is higher than that of the surface layer.

The present invention provides a nonwoven fabric laminate sheet that has good water retention, excellent heat retention and a good feel when used in a wet state, and is suitable for use as a body cleansing sheet.

The nonwoven laminated sheet of the present invention has an intermediate layer containing an airlaid nonwoven fabric formed by the airlaid method. The airlaid method generally includes a step of dry disintegrating and mixing raw fibers to form a fiber web, a step of spraying an aqueous adhesive as a binder onto the fiber web, and a dry heating step of bonding the fibers of the fiber web with the aqueous adhesive. In the airlaid method, if the raw fibers contain thermally adhesive fibers, the fibers of the fiber web can be bonded to each other by melt bonding of the thermally adhesive fibers in the dry heating step without spraying the aqueous adhesive. The thermally adhesive fibers and the aqueous adhesive can be sprayed together. The intermediate layer may contain a nonwoven fabric other than the airlaid nonwoven fabric, but the proportion of the airlaid nonwoven fabric in the intermediate layer is preferably 80% by volume or more, more preferably 90% by volume or more, and even more preferably 95% by volume.

In the present invention, the intermediate layer of the nonwoven fabric laminate sheet contains a thermal adhesive fiber. As the thermal adhesive fiber contained in the intermediate layer, a core-sheath composite type or an eccentric side-by-side type thermal adhesive composite synthetic fiber can be particularly preferably used. Examples of polymers constituting the sheath portion or the outer periphery of the fiber include polyethylene and polypropylene. As the polymer constituting the core component or the inner layer portion of the fiber, a polymer that has a higher melting point than the sheath portion or the outer periphery of the fiber and does not show a significant change at the dry heating temperature is used. Examples of such combinations include polyethylene/polypropylene, polyethylene/polyester, polypropylene/polyester, etc. (Note that these do not include splittable composite fibers described later). These polymers may be modified to the extent that the action as a thermal adhesive fiber is not inhibited. From the viewpoint of achieving both a good usability and sufficient strength and flexibility, the thermal adhesive fiber contained in the intermediate layer of the nonwoven fabric laminate sheet of the present invention is preferably contained in a ratio of 10 to 45% by mass, more preferably 15 to 40% by mass, of the airlaid nonwoven fabric constituting the intermediate layer. If the intermediate layer of the nonwoven fabric laminated sheet of the present invention contains less than 10% by mass of thermally adhesive fibers, it may be difficult to achieve both sufficient strength and flexibility, and the feel of use may be poor. If the intermediate layer of the nonwoven fabric laminated sheet of the present invention contains more than 45% by mass of thermally adhesive fibers, the flexibility may be reduced and the feel of use may be poor.

The intermediate layer of the nonwoven fabric laminated sheet of the present invention contains cellulosic fibers. Cellulosic fibers have hydrophilic groups such as hydroxyl groups and carboxyl groups, and exhibit high hydrophilicity and water retention. Examples of cellulosic fibers that can be used include wood pulp made from coniferous or broadleaf trees, non-wood pulp made from rags, linters, linen, straw, bagasse, kenaf, etc., pulp fibers obtained by disintegrating waste paper pulp, natural fibers such as cotton and hemp, regenerated cellulose fibers such as rayon, lyocell, and cupra, and semi-synthetic fibers such as acetate fibers and triacetate fibers. As the cellulosic fibers contained in the intermediate layer of the nonwoven fabric laminated sheet of the present invention, it is preferable to use pulp fibers in view of the balance between cost and water retention. Two or more types of the above cellulosic fibers can be used in combination. The cellulosic fibers contained in the intermediate layer of the nonwoven fabric laminated sheet of the present invention are 62% by mass or more of the total mass of the intermediate layer, and preferably 62 to 90% by mass or more. If the ratio of cellulose fibers is less than 62% by mass, the water retention capacity is insufficient and the amount of water that can be absorbed is insufficient, so when it is heated in a wet state and used as a body cleaning sheet, the heat retention is insufficient. Also, if the ratio of cellulose fibers is more than 90% by mass, the strength of the middle layer is insufficient, and the wiping comfort may be inferior.

The intermediate layer of the nonwoven laminate sheet of the present invention may contain fibers other than thermal adhesive fibers and cellulosic fibers. Examples of fibers other than thermal adhesive fibers and cellulosic fibers include thermoplastic fibers, such as monofibers of polyester, polyamide, polyacrylonitrile, polyethylene, polypropylene, polyurethane, ethylene vinyl alcohol copolymer, polylactic acid, polybutylene succinate, and composite fibers such as polyester/polypropylene splittable composite fibers, polyester/polyethylene splittable composite fibers, and polypropylene/polyethylene splittable composite fibers. Two or more types of the above thermoplastic fibers may be used in combination. When fibers other than thermal adhesive fibers and cellulosic fibers are contained, the amount is preferably 10% by mass or less relative to the airlaid nonwoven fabric formed by the airlaid method.

The intermediate layer of the nonwoven fabric laminated sheet of the present invention may contain an aqueous adhesive. Examples of aqueous adhesives that can be used include aqueous solution type adhesives such as casein, sodium alginate, hydroxyethyl cellulose, sodium carboxymethyl cellulose, polyvinyl alcohol, and sodium polyacrylate, and emulsion type aqueous adhesives such as polyacrylic acid ester, acrylic-styrene copolymer, polyvinyl acetate, ethylene-vinyl acetate copolymer, acrylonitrile-butadiene copolymer, methyl methacrylate-butadiene copolymer, and styrene-butadiene copolymer latex. Although the inclusion of an aqueous adhesive is not essential, if it is contained, it is preferable that the content of the aqueous adhesive is 10% by mass or less relative to the airlaid nonwoven fabric formed by the airlaid method. If the content of the aqueous adhesive exceeds 10% by mass, the flexibility of the nonwoven fabric laminated sheet is reduced and a good feeling of use may not be obtained.

The air-laid nonwoven fabric in the intermediate layer of the nonwoven fabric laminate sheet of the present invention can contain various inorganic particles, organic polymer particles, etc., to the extent that the performance as an intermediate layer is not impaired.

The nonwoven fabric laminated sheet of the present invention has at least a surface layer arranged on both sides of the intermediate layer. For the surface layer of the nonwoven fabric laminated sheet of the present invention, a nonwoven fabric formed by the spunlace method or the spunbond method can be suitably used. In particular, it is preferable to use a nonwoven fabric formed by the spunlace method. In the spunlace method, there are a dry method in which defibrated and mixed fibers are formed into a fiber web by a parallel method or a cross method using a carding machine and a wrapper, and a wet method in which defibrated and mixed fibers in water are dehydrated on a mesh such as a cylinder or a long net to form a fiber web. By spraying a high-pressure jet stream onto the fiber web formed by the dry method or the wet method, three-dimensional entanglement of the fibers is formed, and by heating and drying, a nonwoven fabric that does not contain chemical components that act as binders is obtained. As with general body cleansing sheets, in order to avoid skin sensitization due to chemical components, a nonwoven fabric formed by the binder-free spunlace method can also be suitably used for the surface layer of the nonwoven fabric laminated sheet of the present invention.

The surface layer of the nonwoven laminated sheet of the present invention may contain cellulose-based fibers or thermoplastic fibers. In particular, from the viewpoint of obtaining a good feeling of use, it is preferable that the surface layer contains thermoplastic fibers, and the content of the thermoplastic fibers is preferably 15% by mass or more of the fibers contained in the surface layer. As the cellulose-based fibers, for example, natural fibers such as pulp fibers, cotton, and hemp, regenerated cellulose fibers such as rayon fibers, lyocell fibers, and cupra fibers, and semi-synthetic fibers such as acetate fibers and triacetate fibers can be used. Two or more types of the above cellulose-based fibers can be used in combination. As the thermoplastic fibers, for example, single fibers such as polyester, polyamide, polyacrylonitrile, polyethylene, polyethylene terephthalate, polypropylene, polyurethane, ethylene vinyl alcohol copolymer, polylactic acid, and polybutylene succinate, and composite fibers such as polyester/polypropylene splittable composite fibers, polyester/polyethylene splittable composite fibers, and polypropylene/polyethylene splittable composite fibers can be used. Two or more types of the above thermoplastic fibers can be used in combination.

The surface layer of the nonwoven laminate sheet of the present invention may contain other fibers, such as thermally adhesive fibers, such as core-sheath or eccentric side-by-side thermally adhesive composite synthetic fibers.

The nonwoven fabric laminated sheet of the present invention is characterized in that the intermediate layer and the surface layers arranged on both sides of the intermediate layer are bonded to the intermediate layer via an adhesive component. As a method for forming a nonwoven fabric laminated sheet from a plurality of different nonwoven fabric webs, for example, as described in JP 2017-119931 A, a method of laminating by a method of forming three-dimensional entanglement of fibers by high-pressure water jet processing such as a water jet (so-called water flow entanglement method) is generally known, but there is a problem that the functions of each layer become unclear and the functionality expressed is limited due to significant intermixing between layers. The nonwoven fabric laminated sheet of the present invention is characterized in that each nonwoven fabric web is bonded via an adhesive component to obtain a laminated sheet without actively utilizing the entanglement of fibers between each layer. As the adhesive component, for example, so-called binder resins such as hot melt adhesives, latex adhesives, and emulsion adhesives can be used, and various resins such as polyolefin, synthetic rubber, polyvinyl acetate, polyamide, polyester, and polyurethane can be suitably used. The amount of adhesive component contained in the nonwoven fabric laminate sheet of the present invention is preferably 3 to 15 g/ ^m2 on one surface joining the intermediate layer and the surface layer. If the amount of adhesive component is less than 3 g/ ^m2 , the nonwoven fabric laminate sheet may not have an appropriate strength and may have a poor feel when used. If the amount of adhesive component exceeds 15 g/ ^m2 , the nonwoven fabric laminate sheet itself may have high stiffness and low flexibility, resulting in a poor feel when used.

The nonwoven fabric laminated sheet of the present invention has a basis weight of 100 to 300 g/m ^2. More preferably, it is 150 to 300 g/m ^2. When the basis weight of the nonwoven fabric laminated sheet is less than 100 g/m ² , the feeling of use may be poor in terms of wiping comfort when used as a body cleaning sheet. When the basis weight of the nonwoven fabric laminated sheet exceeds 300 g/m ² , the weight of the moistened body cleaning sheet may be too heavy, resulting in poor feeling of use. In addition, when the basis weight exceeds 300 g/m ² , the moistened body cleaning sheet may be difficult to fold and poor in processability when folded and stored in an individual package due to its strong restoring force.

The nonwoven fabric laminated sheet of the present invention is characterized in that the water retention capacity of the intermediate layer is higher than that of the surface layers (the individual surface layers on both sides of the intermediate layer). The water retention capacity is calculated by the following formula (1).
Water retention capacity (g/m ² ) = Water retention rate (%) / 100 x basis weight (g/m ² ) (1)
The water retention rate in this specification is the water retention rate measured by the method described in JIS L1913:2010. Since the water retention capacity of the intermediate layer is higher than that of the surface layer, when the nonwoven fabric laminated sheet of the present invention is moistened and used as a body cleansing sheet, a large amount of water can be retained in the intermediate layer. This allows the body cleansing sheet to exhibit excellent heat retention when heated for use. In addition, since the amount of water retained in the surface layer can be relatively small, excessive heating of the surface is prevented when heating in a microwave oven or the like, and the surface is easy to touch even after heating, so that the body cleansing sheet can be easily taken out of a package in which the body cleansing sheet is packaged, and an easy-to-use body cleansing sheet can be provided. The difference between the water retention capacity of the intermediate layer and the surface layer (water retention capacity of the intermediate layer (g/m ² ) - water retention capacity of the surface layer (g/m ² )) is preferably 500 g/m ² or more, more preferably 1000 g/m ² or more.

The water retention capacity of the nonwoven fabric laminated sheet of the present invention is preferably 1600 g/ ^m2 or more from the viewpoint of heat retention, and more preferably 1800 g/m2 or ^more . Furthermore, if the water retention rate of the nonwoven fabric for the surface layer exceeds 1000%, the feeling of use during wiping may decrease, so the water retention rate is preferably 1000% or less.

When making a body cleansing sheet using the nonwoven laminate sheet of the present invention, the following method is suitable as an example.

In the first step, the nonwoven laminated sheet of the present invention is impregnated with a medicinal solution. The medicinal solution can be a general formulation mainly composed of water. Additives that can be blended include moisturizers such as glycerin, polypropylene glycol, and hyaluronic acid, natural extracts such as aloe vera leaf extract, pine extract, and peach leaf extract, fragrances such as limonene, citral, and menthol, antibacterial substances such as phenoxyethanol, benzalkonium chloride, and propyl iodide butylcarbamate, and various surfactants.

It is preferable to impregnate the nonwoven fabric laminate sheet of the present invention with a chemical solution at an impregnation rate of 250 to 500% relative to the basis weight. If the impregnation rate is less than 250%, the amount of chemical solution held by the nonwoven fabric laminate sheet of the present invention may be insufficient, resulting in insufficient heat retention. On the other hand, if the impregnation rate of the chemical solution exceeds 500%, the chemical solution may overflow from the nonwoven fabric laminate sheet during use, resulting in a poor feel when used.

In the second step, the nonwoven laminate sheet that has been impregnated and moistened with the drug solution in the first step is preferably enclosed and sealed in a moisture-proof individual packaging bag. The individual packaging bags can be made of soft packaging materials such as single films of low-density polyethylene, high-density polyethylene, biaxially oriented polypropylene, biaxially oriented polyethylene terephthalate, biaxially oriented nylon, polystyrene, etc., composite films of biaxially oriented polypropylene/low-density polyethylene, biaxially oriented polypropylene/linear low-density polyethylene, biaxially oriented polypropylene/unstretched polypropylene, biaxially oriented polyethylene terephthalate/low-density polyethylene, biaxially oriented polyethylene terephthalate/linear low-density polyethylene, biaxially oriented polyethylene terephthalate/unstretched polypropylene, biaxially oriented nylon/low-density polyethylene, biaxially oriented nylon/linear low-density polyethylene, polyvinylidene chloride/biaxially oriented polypropylene/linear low-density polyethylene, silica-deposited biaxially oriented polyethylene terephthalate/linear low-density polyethylene, etc., and composite papers of paper/polyvinylidene chloride/unstretched polypropylene, paper/polyvinylidene chloride/linear low-density polyethylene, etc.

In order to suppress evaporation of the drug solution and ensure long-term storage stability, it is more preferable that the water vapor permeability be 30 g/( ^m2 ·24 hr) or less, measured at a temperature of 40±0.5°C and a relative humidity of 90±2% (temperature and humidity conditions: condition B) in accordance with JIS Z0208: 1976 for packaging materials. The smaller the water vapor permeability value, the less water vapor passes through and the more water vapor evaporation can be suppressed.

When the nonwoven laminated sheet of the present invention is packaged and enclosed in the individual packaging bag, there are no particular limitations as long as the bag making and processing method can be such as pillow packaging, three-sided seal packaging, four-sided seal packaging, etc., as long as it can seal the cleaning sheet. In addition, examples of sealing methods include bonding with an adhesive, heat sealing, ultrasonic sealing, etc., but heat sealing or ultrasonic sealing is preferred from the viewpoints of preventing contamination by foreign matter and processing speed.

When the nonwoven fabric laminate sheet of the present invention is packaged and enclosed using the above-mentioned packaging material, it is preferable to fold the sheet before packaging and enclosing it. By folding the sheet before packaging and enclosing it, the individual packaging bag can be made compact, making it easy to carry and store, and it can be used as a body cleaning sheet.

The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. Here, "parts by mass" and "% by mass" represent the amount of dry solids or the amount of actual components.

Example 1
<Preparation of Nonwoven Fabric for Intermediate Layer>
65 parts by mass of pulp fibers, which are cellulosic fibers obtained by defibrating bleached coniferous kraft pulp using a dry defibrator, and 35 parts by mass of polypropylene/polyethylene core-sheath composite fibers (core: polypropylene, sheath: polyethylene) with a fineness of 2.2 dtex and fiber length of 5 mm as thermal adhesive synthetic fibers were mixed in an airlaid web forming device, and the fiber web deposited on a mesh conveyor having a suction mechanism together with an air flow was heated to melt the sheath of the thermal adhesive synthetic fiber, to produce a nonwoven fabric formed by the airlaid method having a basis weight of 190 g/ ^m2 .

<Preparation of Nonwoven Fabric for Surface Layer>
20 parts by mass of rayon fiber, a cellulose fiber with a fineness of 1.7 dtex and a fiber length of 38 mm, and 80 parts by mass of polyethylene terephthalate fiber, a thermoplastic fiber with a fineness of 1.7 dtex and a fiber length of 38 mm, were mixed together to form a cross-type fiber web using a carding machine and a cross wrapper. The fiber web was hydroentangled and dried by heating to produce a nonwoven fabric formed by the spunlace method with a basis weight of 40 g/ ^m2 .

<Preparation of nonwoven fabric laminate sheet>
Powdered polyethylene hot melt was sprayed as an adhesive component on one side of the intermediate nonwoven fabric prepared above to an amount of 5 g/ ^m2 , and the surface layer nonwoven fabric prepared above was laminated thereon, heated and melted to bond them together. Next, powdered polyethylene hot melt was sprayed as an adhesive component on the other side of the intermediate nonwoven fabric in the same manner to an amount of 5 g/ ^m2 , and the surface layer nonwoven fabric prepared above was laminated thereon, heated and melted to bond them together, to produce a nonwoven fabric laminate sheet with a basis weight of 280 g/ ^m2 having the surface layer nonwoven fabric on both sides of the intermediate nonwoven fabric.

Example 2
A nonwoven fabric laminated sheet of Example 2 having a basis weight of 170 g/ ^m2 was produced in the same manner as in Example 1, except that the nonwoven fabric for the intermediate layer had a basis weight of 80 g/ ^m2 .

Example 3
A nonwoven fabric for an intermediate layer was produced in the same manner as in Example 1, except that the intermediate layer nonwoven fabric contained 70 parts by mass of pulp fiber, 30 parts by mass of polypropylene/polyethylene core-sheath composite fiber, and had a basis weight of 150 g/ ^m2 . A nonwoven fabric for a surface layer was produced in the same manner as in Example 1, except that the intermediate layer nonwoven fabric contained 65 parts by mass of rayon fiber, 35 parts by mass of polyethylene terephthalate fiber, and had a basis weight of 60 g/ ^m2 . A nonwoven fabric laminated sheet of Example 3 having a basis weight of 280 g/ ^m2 was produced using the intermediate layer nonwoven fabric and the surface layer nonwoven fabric in the same manner as in Example 1.

Example 4
A nonwoven fabric laminated sheet of Example 4 having a basis weight of 170 g/ ^m2 was produced in the same manner as in Example 2, except that the nonwoven fabric for the surface layer was formed by the spunlace method using only polyethylene terephthalate fiber, which is a thermoplastic fiber, without using rayon fiber, which is a cellulosic fiber, to form a nonwoven fabric having a basis weight of 40 g/ ^m2 .

Example 5
A nonwoven fabric laminated sheet of Example 5 having a basis weight of 170 g/ ^m2 was produced in the same manner as in Example 1, except that the nonwoven fabric for the surface layer was formed by the spunlace method using only rayon fiber, which is a cellulosic fiber, without using polyethylene terephthalate fiber, which is a thermoplastic fiber, ^and the nonwoven fabric for the intermediate layer had a basis weight of 104 g/ ^m2 .

Example 6
A nonwoven fabric laminated sheet of Example 6 having a basis weight of 170 g/ ^m2 was produced in the same manner as in Example 2, except that the intermediate layer nonwoven fabric contained 82 parts by mass of pulp fiber, 18 parts by mass of polypropylene/polyethylene core-sheath composite fiber, and had a basis weight of 80 g/ ^m2.

(Comparative Example 1)
The nonwoven fabric for the surface layer of Example 1 was used as it was to prepare a nonwoven fabric sheet of Comparative Example 1.

(Comparative Example 2)
A fiber web was formed by a cross method using a carding machine and a cross wrapper using rayon fiber, which is a cellulosic fiber having a fineness of 1.7 dtex and a fiber length of 38 mm. The fiber web was hydroentangled and dried by heating to form a nonwoven fabric having a basis weight of 40 g/ ^m2 by a spunlace method, which was used as the nonwoven fabric sheet of Comparative Example 2.

(Comparative Example 3)
A nonwoven fabric sheet of Comparative Example 3 was produced in the same manner as in Comparative Example 2, except that the basis weight of the nonwoven fabric sheet of Comparative Example 2 was 80 g/ ^m2 .

(Comparative Example 4)
A nonwoven fabric laminated sheet of Comparative Example 4 having a basis weight of 170 g/m2 was prepared in the same manner as in Example 2, except that for the nonwoven fabric for the intermediate layer of Example 2, 60 parts by mass of pulp fiber, which is a cellulosic fiber, and 40 parts by mass of polypropylene/polyethylene core- ^sheath composite fiber, which is a thermal adhesive synthetic fiber, were used.

<Measurement of water retention capacity>
The water retention capacity of the produced nonwoven fabric laminate sheet and each laminated nonwoven fabric sheet was measured as follows. First, the water retention rate was measured according to JIS L1913:2010. Specifically, three test pieces of 100 mm x 100 mm were taken in an environment of 20 ± 2 ° C., and their mass (Wd) was measured, followed by immersion in pure water for 20 minutes, removal of the test pieces from the water with tweezers, dripping water for 1 minute, and then measuring the mass (Ww) of the test pieces. The water retention rate was calculated from the following formula (2).
Water retention rate (%) = (Ww - Wd) / Wd × 100 (2)
The water retention rate calculated based on the formula (2) was used to calculate the water retention capacity based on the above formula (1). The measured water retention rates and water retention capacities of the intermediate layer nonwoven fabric, the surface layer nonwoven fabric, the nonwoven fabric laminated sheet, and the nonwoven fabric sheet are shown in Table 1.

<Evaluation of heat retention>
The nonwoven laminated sheets or nonwoven sheets of Examples 1 to 6 and Comparative Examples 1 to 4 were cut to a size of 200 mm in width and 300 mm in length. After that, the sheets were impregnated with a drug solution (aqueous solution containing 5% by mass of propylene glycol, 0.2% by mass of phenoxyethanol, 0.02% by mass of benzalkonium chloride, and 0.02% by mass of iodide propynyl butylcarbamate), and the solution was appropriately removed to prepare moistened body-cleaning sheets containing a drug solution in an amount four times the mass of the sample before impregnation. The moistened body-cleaning sheets were placed in a moisture-proof bag and sealed with a heat seal to prepare individually packaged body-cleaning sheets. The individually packaged body cleansing sheets made from the nonwoven fabric laminated sheets or nonwoven fabric sheets of Examples 1 to 6 and Comparative Examples 1 to 4 were thoroughly heated to 60° C. in a towel warmer, then removed from the individual packaging bags and left to stand for 2 minutes in a fully spread-out state in an environment of 26° C. and 50% relative humidity. The temperature of the sheet surface was measured using a thermometer TNA-310DL (manufactured by ICHINEN TASCO Co., Ltd.) with a K thermocouple as a sensor. The results are shown in Table 2.

<Evaluation of Usability>
The individually packaged body cleansing sheets used in the "Evaluation of Heat Retention" were evaluated for usability. The results are shown in Table 3.

The "evaluation of usability" was based on the following criteria:
○: It was easy to wipe off and felt good on the skin.
△: Wiping was somewhat difficult.
×: Wiping was difficult.

The above results show that the nonwoven fabric laminate sheet of the present invention has excellent water retention capacity, and is a nonwoven fabric laminate sheet that has excellent heat retention and usability when used in a wet state.

The nonwoven laminate sheet of the present invention can be used as a moistened body cleaning sheet in homes, medical facilities, welfare facilities, nursing care facilities, beauty facilities, exercise facilities, etc.

Claims (1)

A nonwoven fabric laminate sheet having a basis weight of 100 to 300 g/ ^m2 , comprising at least an intermediate layer containing an airlaid nonwoven fabric, and surface layers bonded to both sides of the intermediate layer via an adhesive component, wherein the intermediate layer contains a thermal adhesive fiber and 62 mass% or more of a cellulosic fiber relative to the total mass of the intermediate layer, and the water retention capacity of the intermediate layer is higher than that of the surface layer.