JP2021142191A - Wet sheet and manufacturing method of wet sheet - Google Patents

Abstract

To provide a wet sheet having an excellent moisture-retaining property and manufacturing method of the wet sheet.SOLUTION: After a base material sheet 10 to which cellulose nanofibers are applied is heat-dried, the base material sheet 10 by dry weight is impregnated with a 200 mass% to 500 mass% of milky solution-based drug solution in which 0.001 mass% to 0.100 mass% of oil solution and at least two types or more of emulsifiers are blended, to provide a wet sheet S having excellent moisture-retaining property more than that of the wet sheet formed by applying the emulsion-based drug solution to the base material sheet 10.SELECTED DRAWING: Figure 1

Description

The present invention relates to a wet sheet and a method for producing the wet sheet.

A wet sheet obtained by impregnating a sheet base material with a milky lotion-based chemical solution containing an oil agent is known to have excellent moisturizing performance (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2019-178094

However, there has been a demand for a wet sheet having more excellent moisturizing performance than a wet sheet impregnated with a milky lotion-based chemical solution.

An object of the present invention is to provide a wet sheet having excellent moisturizing performance and a method for producing the wet sheet.

In order to solve the above problems, the invention according to claim 1 is
A wet sheet in which the base sheet is impregnated with a chemical solution.
The chemical solution contains an oil agent and an emulsifier, and contains
The base material sheet is characterized in that cellulose nanofibers are applied.

The invention according to claim 2 is the wet sheet according to claim 1.
The chemical solution is characterized by containing 0.001% by mass to 0.100% by mass of the oil agent.

The invention according to claim 3 is the wet sheet according to claim 1 or 2.
The chemical solution is impregnated with 200% by mass to 500% by mass with respect to the dry weight of the base material sheet.

The invention according to claim 4 is the wet sheet according to any one of claims 1 to 3.
The cellulose nanofibers is characterized in that it is 0.1g ^{/ m 2} ~10.0g ^/ m 2 coating to said base sheet.

The invention according to claim 5 is a method for manufacturing a wet sheet.
The coating process of applying the cellulose nanofiber solution to the base sheet and
A heat-drying step of heat-drying the base material sheet and
It is characterized by having a chemical solution impregnation step of impregnating the base material sheet with a chemical solution containing an oil agent and an emulsifier.

According to the present invention, it is possible to provide a wet sheet having excellent moisturizing performance and a method for producing the wet sheet.

It is a top view which shows the wet sheet of the Sugi Aya pattern. It is a top view which shows the striped wet sheet. It is a top view which shows the wet sheet of a checkered pattern. It is a top view which shows the wet sheet of a mesh pattern. It is a top view which shows the wet sheet of a curved pattern. It is sectional drawing of the part of VI-VI of FIGS. 1 to 5.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the scope of the invention is not limited to the illustrated examples.

[Wet wipe]
FIG. 1 is a plan view showing a wet sheet S according to the present embodiment.
^{The wet sheet S contains 0.1 g / m 2 to} 10.0 g / m ² , preferably 0.2 g / m ² to cellulose nanofibers (hereinafter, CNF) with respect to the base sheet 10 made of a predetermined fiber. A cleaning sheet that is applied at 5.0 g / m ² and is impregnated with a milky lotion-based chemical solution in which various components are added to purified water. Is. When the coating amount of CNF is at ^{0.1g / m 2 ~10.0g / m 2} , it is possible to realize a wet sheet S which is excellent in moisture retention.
In the product form, the wet sheet S can be housed in a packaging means such as a closed container having a sheet outlet that can be sealed by an opening / closing lid.
When using, the user opens the outlet to open the inner sheet from the one in which the wet sheet S is put directly in the container or bag, or the one in which the bag containing the wet sheet S is put in the container. Pull it out and use it.

[Base sheet]
The base material sheet 10 is a non-woven fabric produced by using a predetermined fiber as a fiber material, for example, by a well-known technique such as spunlace, air-through, airlaid, point bond, spunbond, needle punch and the like. Examples of the predetermined fibers include cellulose fibers such as rayon, lyocell, tencel, and cotton, polyolefin fibers such as polyethylene, polypropylene, and polyvinyl alcohol, polyester fibers such as polyethylene terephthalate and polybutylene terephthalate, and polyamide fibers such as nylon. Can be mentioned. These can be used alone or in combination of two or more, but it is desirable that 1% by mass to 10% by mass of cotton is blended, whereby the wet sheet S impregnated with the emulsion-based chemical solution Can be made less irritating to the skin.

The wet sheet S may be formed by ply (laminating) a plurality of base sheets 10 or may be formed from one base sheet 10. When the wet sheet S has a multi-layer structure, if the inner layer contains 6% to 10% and the outer layer contains 0 to 4%, the chemical retention property can be improved, and the inner layer contains 0% to 4% and the outer layer contains 0% to 4%. When it is contained in 6% to 10%, the user can feel more moisture. The content ratio of cotton in the inner layer and the outer layer is not limited to the above, and may be contained in each layer in a uniform ratio.

As shown in FIG. 1, the base material sheet 10 has a convex portion composed of a high fiber density region 11 and a concave portion composed of a low fiber density region 12, and the high fiber density region 11 and the low fiber density region 11 are formed. A predetermined pattern is formed by arranging the fiber density regions 12 alternately.
As a predetermined pattern, for example, as shown in FIG. 1, a cedar pattern in which a continuous V-shaped portion is formed by lines that are bent in the opposite direction at predetermined intervals can be mentioned.

In the present invention, the angle of the V-shaped portion of the cedar twill pattern (angle of bending of the line) is not particularly limited, but for example, by setting it to 5 ° to 60 °, the diffusivity and liquid permeability of the chemical solution are maximized. Can be good.
Further, as the pattern formed on the base sheet 10, for example, a striped pattern, a lattice pattern, a mesh pattern, a curved pattern, or the like can be used in addition to the cedar pattern. 2 to 5 show a base sheet 10 on which a striped pattern (FIG. 2), a lattice pattern (FIG. 3), a mesh pattern (FIG. 4), and a curved pattern (FIG. 5) are formed, respectively.

In FIGS. 1 to 5, halftone dots are provided in the high fiber density region 11 for convenience of explanation.
Further, the “high fiber density region 11” as used herein means a region having a higher fiber density than the low fiber density region 12, and the density is not particularly limited as long as it is larger than the low fiber density region 12. ..
Further, the "low fiber density region 12" means a region having a lower fiber density than the high fiber density region 11, and the density is not particularly limited as long as it is smaller than the high fiber density region 11.

By having the base sheet 10 having the high fiber density region 11 and the low fiber density region 12, the contact area with the skin can be reduced and the friction with the skin can be reduced. As a result, irritation to the skin can be reduced, so that the wet sheet S of the present invention can be used even by a person with sensitive skin, an infant, or the like.
Further, since the base sheet 10 has the linear recesses (low fiber density region 12), the liquid diffusivity and the liquid permeability are excellent as compared with the flat base sheet, so that the chemical solution is evenly and uniformly spread on the base sheet 10. It will be applied.

The number of lines in each pattern formed by the high fiber density region 11 and the low fiber density region 12 is preferably 3 lines / cm to 7 lines / cm.
Here, the number of lines (lines / cm) referred to in the present specification means how many linear high fiber density regions 11 and linear low fiber density regions 12 exist per 1 cm. There is.
That is, it means how many lines are present in the direction perpendicular to the direction parallel to the linear high fiber density region 11 and the linear low fiber density region 12 provided in parallel (the direction in which the number is the largest). doing. That is, in the case of 4 fibers / cm, it means that two linear high fiber density regions 11 and two low fiber density regions 12 are provided in 1 cm.
When the number of lines is less than 3 lines / cm, the surface of the base sheet 10 approaches flatness, so that the dirt once captured is likely to be transferred. Further, when the number of lines exceeds 7 lines / cm, the volume of the space formed by the high fiber density region 11 and the low fiber density region 12 becomes too small, so that a desired amount of dirt is applied to the low fiber density region 12. It will not be possible to secure it.

FIG. 6 is a cross-sectional view of a portion of VI-VI in FIGS. 1 to 5.
The height (thickness) Hm from the back surface of the high fiber density region 11 is preferably 200 μm or more and less than 600 μm, and the height (thickness) Hd from the back surface of the low fiber density region 12 is, for example, 150 μm or more. , Less than 200 μm is preferable.
At this time, the height difference between the high fiber density region 11 and the low fiber density region 12 is preferably about 50 μm to 100 μm.
If the height difference is less than 50 μm, a large capture effect by the low fiber density region 12 cannot be expected, and a desired wiping amount cannot be secured. If the height difference exceeds 100 μm, the base sheet 10 of the base sheet 10 cannot be expected. This is because the thickness becomes thicker, and the flexibility and the feel of the touch are impaired.

The fiber basis weight of the high fiber density region 11, for ^example, is preferably from 40g / ^{m 2} ~60g / m 2 approximately, the fibers basis weight of the low fiber density regions 12 are, for ^example, 10g / m 2 ^~20g / m ^It is preferably about 2.
When the fiber basis weight satisfies the above range, the thickness becomes suitable, and the base sheet 10 can ensure both strength and flexibility.

In the present embodiment, the convex portion is the high fiber density region 11 and the concave portion is the low fiber density region 12, but the present invention is not limited to this, and the convex portion is the low fiber density region 12 and the concave portion is high. It may be the fiber density region 11. Further, the base sheet 10 preferably has a convex portion which is a high fiber density region 11 and a concave portion which is a low fiber density region 12, but the present invention is not limited to this, and a difference in fiber density is not provided. It doesn't matter.
Further, the area ratio of the high fiber density region 11 and the low fiber density region 12 in the base sheet 10 does not have to be 5: 5, but is preferably in the range of 2: 8 to 8: 2. If one is provided more than four times as much as the other, it is difficult to feel the unevenness, which is not preferable.

[CNF]
CNF has a property of retaining water, is highly safe, and its aqueous solution is a material having a thixo property, which is a fine cellulose fiber obtained by defibrating pulp fiber, and is generally a fiber. It refers to a cellulose fiber containing cellulose fine fibers having a width of nano size (1 nm or more and 1000 nm or less), and the average fiber width is preferably 100 nm or less. For the calculation of the average fiber width, for example, a fixed number average, a median, a mode diameter (mode), or the like is used.

(Pulp fiber that can be used for CNF)
Examples of pulp fibers that can be used as CNF include chemical pulps such as broadleaf pulp (LBKP) and coniferous pulp (NBKP), bleached thermomechanical pulp (BTMP), stone ground pulp (SGP), and pressurized stone ground pulp (PGW). ), Refiner Gland Pulp (RGP), ChemiGrand Pulp (CGP), Thermogrand Pulp (TGP), Gland Pulp (GP), Thermomechanical Pulp (TMP), Chemithermo Mechanical Pulp (CTMP), Refiner Mechanical Pulp (RMP) Machine pulp, tea waste paper, craft envelope waste paper, magazine waste paper, newspaper waste paper, leaflet waste paper, office waste paper, cardboard waste paper, upper white waste paper, Kent waste paper, imitation waste paper, ground ticket waste paper, waste paper waste paper, etc. Examples thereof include pulp and deinked pulp (DIP) obtained by deinking waste paper pulp. These may be used alone or in combination of a plurality of types as long as the effects of the present invention are not impaired.

(Defibration method)
Examples of the defibration method used for producing CNF include mechanical methods such as a high-pressure homogenizer method, a microfluidizer method, a grinder grinding method, a bead mill freeze pulverization method, and an ultrasonic defibration method. It is not limited to.

The CNF that has been mechanically treated (not modified) by the above defibration method or the like, that is, the CNF that has not been modified with a functional group, is a functional group-modified one such as a phosphate group or a carboxymethyl group. Since it has high thermal stability, it can be used in a wider range of applications, but it is also possible to use a functional group-modified CNF such as a phosphate group or a carboxymethyl group in the present invention.
Further, for example, pulp fibers that have been subjected to a mechanical defibration treatment may be subjected to a chemical treatment such as carboxymethylation, or may be subjected to an enzymatic treatment. Examples of the chemically treated CNF include iCNF (individualized CNF) (single nanocellulose) having a diameter of 3 nm to 4 nm, such as TEMPO oxide CNF, phosphate esterified CNF, and phosphite esterified CNF. Be done.
Further, a CNF that has been subjected to only a chemical treatment or an enzyme treatment, or a CNF that has been subjected to a chemical treatment or an enzyme treatment and is subjected to a mechanical defibration treatment may be used.

[CMC]
In addition, in order to prevent aggregation of CNF in the solution, carboxymethyl cellulose (hereinafter, CMC), which is a water-soluble polymer, may be added.
When CNF is added to an aqueous solvent, the microfibril fibers of CNF bind to each other and aggregate. By adding CMC and allowing CNF and CMC to coexist, the OH group of CNF and the OH group of CMC Hydrogen bonds, and the electrostatic interaction of the molecular chains and the steric hindrance effect prevent the CNF from aggregating and allow the CNF to be uniformly dispersed in the solution.

CMC is preferably used because it is an extremely environmentally friendly material because it is obtained from cellulose as a raw material, has moderate biodegradability, and can be incinerated after use. A water-soluble polymer other than CMC may be used as long as it can prevent aggregation in the solution.
When CMC is added, the purified water is 93.000% by mass to 99.790% by mass, and the CNF is 0.002% by mass to 0.020% by mass, assuming that the whole solution is 100.000% by mass. % And CMC are preferably contained in a ratio of 0.100% by mass to 1.000% by mass.
When only CNF is applied without adding CMC, purified water is contained at a ratio of 98.000% by mass to 99.500% by mass and CNF is contained at a ratio of 0.500% by mass to 2.000% by mass. It is preferable to have.

[Chemical solution]
The chemical solution is based on an emulsion in which the main component is water (purified water), an oil agent and an emulsifier are blended in a ratio of 1: 4 to 1:19, and the solution is emulsified.
With such a configuration, the chemical solution of the present embodiment contains an oil component, so that the stool and sebum stains containing a large amount of oil can be easily removed. Therefore, the wet sheet S impregnated with the chemical solution of the present embodiment can firmly wipe off the dirt with a small number of sheets, and the consumer can reduce the purchase amount of the wet sheet S.
In particular, by blending the oil agent and the emulsifier in such a ratio, the emulsion stability of the solution is improved, and the water and the oil agent are solubilized and become translucent or transparent, so that the presence or absence of impurities in the chemical solution can be confirmed. , It becomes easier to perform quality control such as pH measurement, and operability can be improved.
If the ratio of the emulsifier to the oil is lower than the above, it is not desirable because the solution is difficult to emulsify or the emulsion is difficult to become translucent or transparent. Further, even if the ratio of the emulsifier to the oil agent is higher than the above, the emulsifying effect is not so increased and the cost of the emulsifier increases, which is not desirable.

(Oil)
As an oil agent, for example, since it contains a large amount of oleic acid and stearic acid, it has a low viscosity and a smooth and moist feel, has excellent permeability, and contains long-chain fatty acids and phytosterols, so that it has high moisturizing properties. Shea butter to have is used.
The oil agent is not limited to shea butter and may have an emollient effect. Oil, persic oil, peach seed oil, castor oil, sunflower oil, grape seed oil, cottonseed oil, coconut oil, wheat germ oil, rice germ oil, evening primrose oil, hybrid sunflower oil, macadamia nut oil, meadowfoam oil, hazelnut oil, palm kernel Oil, palm oil, palm oil, cacao butter, wood wax, mink oil, turtle oil, egg yolk oil, beef fat, milk fat, pork fat, horse oil, jojoba oil, carnauba wax, candela wax, rice bran, orange raffy oil, Mitsuro, Celac, Lanorin, Montan wax, Squalene, Squalane, Liquid paraffin, Paraffin, Microcrystalin wax, Vaseline, Soft liquid isoparaffin, Hydrogenated polyisobutylene, Ozokerite, Celesin, α-olein fin oligomer, Polybutene, Polyethylene, etc. Can be used.
The oil agent is blended in a ratio of 0.001% by mass to 0.100% by mass with respect to all the components of the chemical solution. If it is less than 0.001% by mass, the effect of the oil agent will not be exhibited so much, which is not desirable. On the other hand, if it is more than 0.100% by mass, the viscosity becomes large, stickiness occurs, and the usability deteriorates, which is not desirable.

(emulsifier)
The emulsifier includes nonionics such as polyoxyalkylene alkyl ethers, polyoxyalkylene alkyl phenyl ethers, polyoxyalkylene alkyl esters, polyoxyalkylene sorbitan alkyl esters, sorbitan alkyl esters, polyethylene glycol and polypropylene glycol. A surfactant or the like is used.
It is desirable that at least two types of emulsifiers are blended. Since an oil agent such as shea butter is composed of a plurality of types of fatty acids, it can be made easier to emulsify by blending a plurality of types of emulsifiers.

(Moisturizer)
In addition, a moisturizer may be added to the chemical solution. As a moisturizer, glycerin or the like, which is less irritating to the skin, is used, and by blending this with an oil agent, the water retention of the wet sheet S can be improved, and dirt can be wiped off without rubbing many times. It becomes possible to reduce the irritation to the skin.
The moisturizer is blended in a proportion of 1% by mass to 10% by mass with respect to all the components of the chemical solution. If it is less than 1% by mass, the moisturizing effect is not improved so much, and if it is more than 10% by mass, the viscosity of the chemical solution becomes too high and the impregnation performance becomes low. In addition, it is not desirable because it causes stickiness and deteriorates usability.

(Preservative)
In addition, hexyl glycerin or ethylhexyl glycerin may be added to the chemical solution as a preservative, and any of commercially available products, chemically synthesized products, natural products derived from animals and plants, and those obtained by fermentation or gene recombination methods. May be used. In addition, hexylglycerin or ethylhexylglycerin is a substance having a wide antibacterial spectrum and a high antibacterial effect. Further, hexyl glycerin or ethyl hexyl glycerin has a moisturizing function, and by containing this, the water retention property of the wet sheet S can be enhanced.

Preservatives also include sodium benzoate. Sodium benzoate is, for example, a substance having an antibacterial effect against molds, yeasts, aerobic bacteria and the like.
Sodium benzoate exerts an antiseptic effect at pH 5 or lower. That is, when the pH of the chemical solution becomes higher than 5, the antiseptic effect of sodium benzoate is almost lost. In addition, in general, when the pH is lower than 3, it becomes strongly acidic, which causes irritation to the skin and may cause rough skin. Therefore, it is desirable that the pH of the chemical solution is adjusted to the range of 3 to 5.

Specifically, ethylhexyl glycerin is blended in a proportion of 0.05% by mass to 0.10% by mass and sodium benzoate in a proportion of 0.075% by mass to 0.100% by mass with respect to all the components of the drug solution.
Alternatively, hexylglycerin is blended in an proportion of 0.1% by mass to 0.5% by mass and sodium benzoate is blended in a proportion of 0.05% by mass to 0.10% by mass with respect to all the components of the drug solution.
By making such a combination, the antiseptic effect can be exerted more effectively.

In addition, for example, phenoxyethanol, benzalkonium chloride, cetylpyridinium chloride, a chelating agent and the like can be blended as the preservative.

(Immersion rate)
The impregnation rate of this chemical solution can be 200% by mass to 500% by mass with respect to the dry weight of the base sheet 10.
The conditions for measuring the dry weight of the base sheet 10 are a temperature of 25 ° C. and a humidity of 40%. Further, the impregnation rate of 200% by mass means that 200 g of the chemical solution is impregnated with the base sheet 10 having a dry weight of 100 g, and the impregnation rate of 500% by mass means that the base sheet has a dry weight of 100 g. It means that 500 g of the chemical solution is impregnated with respect to 10.
If the impregnation rate is less than 200% by mass, the liquid content does not sufficiently permeate and uneven impregnation occurs, and the components in the chemical solution tend to be unevenly distributed. If the impregnation rate is more than 500% by mass, the chemical solution drips during use. It will be easier.

[Manufacturing method of wet sheet]
Next, a method for manufacturing the wet sheet S will be described.
The wet sheet S is, for example, a laminating step of laminating a plurality of fiber layers to prepare a base sheet 10, a coating step of applying a CNF solution to the base sheet 10, and heat drying of the base sheet 10 by heat drying. It comprises a step and a chemical impregnation step of impregnating a milky lotion-based chemical.

(Laminating process)
In the laminating step, a base sheet 10 in which a plurality of fiber layers are entangled with each other in the boundary region thereof can be produced by a water flow entanglement method.

(Applying process)
The coating step is a step of applying CNF to the base sheet 10, and the method thereof is to dissolve CNF in a solvent to prepare a CNF dispersion liquid, and then apply this CNF dispersion liquid to the base material sheet 10 and dry it. As a result, a known method such as adhesion formation on the target sheet can be used. When the liquid CNF is applied to the base sheet 10 by the manufacturing method of applying the liquid CNF in this way, the CNF partially permeates into the sheet, but the CNF is concentrated on the surface, so that the CNF can be adhered and formed on the outer layer. .. The solvent for dispersing CNF is not particularly limited, but water, lower alcohols such as ethanol, and volatile organic solvents such as acetone can be used.
For the application of the CNF dispersion liquid, a conventionally known application method such as a transfer method by a letterpress method or the like can be arbitrarily used in addition to spraying on the target surface.

(Heat drying process)
In the heat drying step, a method in which the base sheet 10 coated with the CNF solution is allowed to stand in a constant temperature bath to be dried, or a method in which the base sheet 10 is directly brought into contact with the surface of a heating roll such as a Yankee drum to be dried. Etc., a heat drying method using a conventionally known heat drying facility can be arbitrarily used.
Further, as the drying equipment, equipment by infrared irradiation may be used. In this case, a plurality of infrared irradiation units are arranged in parallel in the transport direction of the base sheet 10, and the transported base sheet 10 is irradiated with infrared rays to dry it. Since moisture is generated by infrared rays and dried, uniform drying is possible and wrinkles can be prevented.
In the present invention, in order to prevent the CNF applied to the surface of the base sheet 10 from peeling off, it is preferable to perform heat drying in a constant temperature bath or an infrared irradiation device.

(Embossing process)
In the embossing step, for example, the high fiber density region 11 can be formed by thermal embossing under the conditions of a temperature of 80 ° C. to 130 ° C. and an embossing pressure of 0.2 MPa to 1.0 MPa.
By this embossing step, when the wet sheet S has a multi-layer structure, the fibers of the inner layer enter the fibers of the outer layer and come out to the surface of the outer layer or the vicinity of the surface.
As a result, when the inner layer contains hydrophilic fibers, it comes out on the surface of the outer layer or in the vicinity of the surface, and liquid stains can be easily wiped off.
The low fiber density region 12 can be formed by designing the embossed roll forming the high fiber density region 11 so as to exclude the shape of the low fiber density region 12.

(Chemical solution impregnation process)
In the chemical solution impregnation step, the heat-dried base sheet 10 is impregnated with a milky lotion-based chemical solution. Alternatively, a known roll transfer technique of a doctor chamber method using a transfer roll, a two-roll type or a three-roll type using a pickup roll can be adopted.
The rotor dampening spray method has an advantage that a small amount of spray liquid can be uniformly applied while suppressing the scattering of mist droplets, and the spray speed and the particle size of the mist can be easily adjusted. Further, the doctor chamber method has an advantage that the amount of the chemical solution to be impregnated can be finely adjusted by designing the number of cells and the number of lines of the transfer roll.

The wet sheet S manufacturing process of the present embodiment includes a step of applying (impregnating) CNF to the base sheet 10 and drying it (coating step, heat drying step) and a base material coated with CNF. It suffices to have a step (chemical solution impregnation step) of applying (impregnating) the emulsion-based chemical solution to the sheet 10, and other steps may be added as appropriate.

Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited thereto.

[Create sample]
First, rayon having a fiber diameter of 1.67 dtex and a fiber length of 38 mm was entangled at a ratio of 50%, and PET having a fiber diameter of 1.56 dtex and a fiber length of 38 mm was entangled by a water flow confounding method. A base sheet 10 of / m ^{2 was prepared.}
Next, 0.47 g of a CNF solution containing 1% by mass of machine-treated CNF and 99% by mass of purified water was applied (CNF application amount: 0.24 g / m ² ), and the mixture was allowed to stand in a constant temperature bath at 60 ° C. for 10 minutes. It was placed and heat-dried to generate a CNF sheet.
Next, the amount of keratin water at 5 cm, 8 cm, 11 cm, 14 cm, and 17 cm from the wrist was measured, and the operations of Comparative Examples 1-4 and Example 1 below were performed using the base sheet 10 or the CNF sheet. Moisture Checker MY707S (manufactured by Scala Co., Ltd.) was used to measure the water content of the keratin.

(Example 1)
The CNF sheet was impregnated with a milky lotion-based chemical solution (hereinafter, milky lotion A) blended at the ratio shown in Table I below in an amount of 340% by mass, and a portion 17 cm from the wrist was lightly wiped 5 times.

(Comparative Example 1)
Nothing was done 5 cm from the wrist.
(Comparative Example 2)
A 0.1 mL / L sodium hydrogen carbonate solution (alkaline solution) containing 0.84% by mass of sodium hydrogen carbonate and 99.16% by mass of purified water was impregnated with 340% by mass of the base sheet 10 from the wrist. The 8 cm area was lightly wiped 5 times.
(Comparative Example 3)
The base sheet 10 was impregnated with a water-based chemical solution prepared in the ratio shown in Table I below in an amount of 340% by mass, and the portion 11 cm from the wrist was lightly wiped 5 times.
(Comparative Example 4)
The base sheet 10 was impregnated with the emulsion A in an amount of 340% by mass, and the portion 14 cm from the wrist was lightly wiped off 5 times.

[Test: Moisturizing performance survey]
After the operations of Comparative Examples 1-4 and Example 1, keratin moisture after 5 minutes, 10 minutes, 15 minutes, 20 minutes, 25 minutes, 30 minutes, 45 minutes, and 60 minutes at each location. For the amount, the rate of change (%) from before the operation of each Comparative Example and Example was measured.
Such a test was carried out three times on different days, and the average value of the rate of change in the keratin water content after the operation of each Comparative Example and Example was calculated.
The test results are shown in Table II.

[evaluation]
Comparing Comparative Examples 1-4, it can be seen that the keratinous water content can be increased by wiping with the base sheet 10 impregnated with the emulsion-based chemical solution. However, comparing Example 1 and Comparative Example 4, the base sheet It can be seen that the amount of keratin water can be further increased by impregnating the CNF sheet coated with CNF to the emulsion-based chemical solution.
It is presumed that this is because two types of protective films are formed on the skin by the oil contained in the emulsion-based chemical solution and the CNF applied to the base sheet 10, and the moisturizing property is enhanced.

(Effect of embodiment)
As shown above, by impregnating the base sheet 10 coated with CNF with the emulsion-based chemical solution, the wet sheet has excellent moisturizing properties as compared with the wet sheet in which the base sheet 10 is impregnated with the emulsion-based chemical solution. S can be generated.
Further, in general, when CNF is mixed with a chemical solution, the viscosity of the chemical solution increases, so that it is difficult to uniformly impregnate the base sheet 10 with the CNF. However, the wet sheet S of the present embodiment has the base sheet 10 Since the CNF sheet coated with CNF is impregnated with the chemical solution, it does not have such a problem.

In addition, it goes without saying that the specific detailed structure and the like can be changed as appropriate.
For example, the wet sheet S is intended to be used for baby wipes, adult bodies, wipes, and the like, but is not limited thereto. Further, the chemical solution impregnated in the wet sheet S can also be changed according to the intended use.

S wet sheet 10 base sheet

Claims (5)

A wet sheet in which the base sheet is impregnated with a chemical solution.
The chemical solution contains an oil agent and an emulsifier, and contains
The base material sheet is a wet sheet to which cellulose nanofibers are applied. The wet sheet according to claim 1, wherein the chemical solution contains 0.001% by mass to 0.100% by mass of the oil agent. The wet sheet according to claim 1 or 2, wherein the chemical solution is impregnated with 200% by mass to 500% by mass with respect to the dry weight of the base material sheet. The cellulose nanofibers, wet sheet according to any one of claims 1 to 3, characterized in that it is 0.1g ^/ m ² ~10.0g / m 2 coating to the base sheet .. It is a method of manufacturing wet sheets.
The coating process of applying the cellulose nanofiber solution to the base sheet and
A heat-drying step of heat-drying the base material sheet and
A method for producing a wet sheet, which comprises a chemical solution impregnation step of impregnating the base material sheet with a chemical solution containing an oil agent and an emulsifier.

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