JP2018199220A - Laminate sheet having water-soluble nanofiber layer - Google Patents

Abstract

To provide a laminate sheet obtained by providing, on a sheet layer, a nanofiber layer containing a thickening polysaccharide having a thickening action or gelling action during dissolution into water, and to further provide means for compensating for shortage of strength of gel and holding the laminate sheet in the sheet form.SOLUTION: Provided is a laminate sheet in which, by using a thickening polysaccharide, part of which is particulate having an average particle diameter of 1-15 μm, as a thickening polysaccharide, a nanofiber layer is formed stably, and solubility of the nanofiber layer is made favorable. Provided is a laminate sheet obtained by laminating a gel layer having a weak shape retaining ability and a sheet layer made of thermoplastic resin for reinforcing the gel layer. Provided is a method of manufacturing a laminate sheet, in which, using a spinning solution obtained by dispersing a thickening polysaccharide which is particulate having an average particle diameter of 1-15 μm and a water-soluble polymer into a solvent which is a good solvent for the water-soluble polymer and a poor solvent for the thickening polysaccharide, a nanofiber layer is formed by an electrospinning method, a sheet layer is formed by extruding a thermoplastic resin, and the nanofiber layer is extruded for laminate molding to form a laminate sheet.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a laminated sheet having a water-soluble nanofiber layer on a sheet layer, and more particularly to a laminated sheet useful for moistening the surface of an object with water or lotion.

In recent years, gel-like cosmetics have been widely used. Such cosmetics apply a highly viscous liquid to the skin, thereby forming a thick gel layer on the skin and bringing about a cosmetic function such as moisturizing (Patent Document 1, etc.).
In addition, a sheet in which a nanofiber layer is formed on a base material layer by an electrospinning method has been proposed (Patent Documents 2, 3, etc.), and the sheet or object is moistened and the sheet is applied to the surface of the object. The substrate layer can then be peeled off, leaving a wet nanofiber layer on the surface of the object.
In addition, in order to ensure stable and reliable spinning by an electrospinning method, a fiber structure is formed by adding a water-soluble polymer such as polyethylene glycol to a spinning solution (Patent Document 4, etc.).
Further, a dry gel sheet in which a gelling agent having a thickening action or a gelling action at the time of water absorption or water-solubility such as xanthan gum or mannan is formed into a sheet is disclosed (Patent Document 5).

Further, gels used for face packs and the like themselves are insufficient in strength to maintain a sheet shape, and such gels are usually accompanied by a support (Patent Document 1, etc.). For example, it is disclosed that the flexibility of a gel precursor or wet gel is reinforced by entanglement of the gel precursor with a net (Patent Document 6). In addition, a support such as a non-woven fabric is used in applications such as face packs, but an adhesive is used when adhesion between the support (non-woven fabric or the like) and the gel or gel precursor layer is insufficient. (Patent Document 7).
On the other hand, a laminated sheet in which a thermoplastic resin layer is formed on a paper substrate by an extrusion laminating method or the like is widely used (Patent Document 8, etc.).

JP2009-221391A JP 2010-167780 A JP 2010-168722 A Special table 2006-501949 (WO2003 / 031637) JP2011-102257A JP-A-1-164304 Special table 2014-534040 JP 2005-342997 A

Substances having a thickening action or a gelling action (for example, thickening polysaccharides) are useful as gel-like cosmetics. Further, in order to obtain a gel-like substance by contact with a solvent such as water, it is preferable to make such a substance into a nanofiber by an electrospinning method or the like (Patent Documents 3, 4, etc.).
However, it is generally difficult to spin a substance having such a thickening or gelling action by an electrospinning method. Therefore, for example, in Cited Document 5, a substance having a thickening action or a gelling action as in the present invention is used in the form of a sheet. On the other hand, in Cited Document 2, the nanofiber layer is formed by the electrospinning method, but a substance having no thickening action or gelling action is used.
In addition, in order to make up for the lack of strength of the gel precursor used in the face pack or the like, if an originally unnecessary net or the like is used (Patent Document 6 etc.), the removal is troublesome and the cost is increased. Not very desirable. In addition, when an adhesive or the like is used between the support (nonwoven fabric or the like) and the gel layer (Patent Document 7 or the like), particularly in applications where the gel layer is applied to human skin, the toxicity of the adhesive May be a problem, and is not preferable.
Therefore, the present invention aims to provide a laminated sheet in which a nanofiber layer containing a thickening polysaccharide having a thickening action or a gelling action at the time of aqueous solution is provided on the sheet layer. In addition, an object of the present invention is to provide a means free from the above problems in order to hold the sheet.

As a result of intensive studies on the above problems, the inventors of the present invention have obtained a laminated sheet in which a nanofiber layer is provided on a sheet layer, and the nanofiber layer is mainly formed by a water-soluble polymer. It has been found that a nanofiber layer containing a thickening polysaccharide can be easily gelled by contact with a solvent such as water by taking a form in which particles formed mainly from the thickening polysaccharide are dispersed. Such a nanofiber layer dissolves the water-soluble polymer using a solvent that is a good solvent for the water-soluble polymer and a poor solvent for the thickening polysaccharide, and disperses the thickening polysaccharide therein. Then, it can be formed by the electrospinning method using the obtained spinning solution. Furthermore, the present inventors use the thickening polysaccharide having an average particle diameter in a certain range as the thickening polysaccharide, so that the nanofiber layer is stably formed, and the solubility of the nanofiber layer is also good. As a result, the present invention has been completed.
Furthermore, in order to laminate a gel layer having a weak shape retaining property and a sheet layer made of a thermoplastic resin for reinforcing the gel layer, an extrusion laminating method is used as compared with other methods (for example, Comparative Example 4 described later). It was found that it is excellent to use.

That is, the present invention is a laminated sheet comprising a sheet layer and a nanofiber layer provided on the sheet layer, wherein the nanofiber layer is a water-soluble polymer (excluding the thickening polysaccharide) and the thickening polysaccharide. And at least a part of the thickening polysaccharide is a laminated sheet having an average particle diameter of 1 to 15 μm.
Further, the present invention is a method for producing the laminated sheet,
(1) A nanofiber layer is made of a thick polysaccharide having a mean particle size of 1 to 15 μm and a water-soluble polymer, which is a good solvent for the water-soluble polymer and a poor solvent for the thick polysaccharide. A step of forming by electrospinning using a spinning solution dissolved or dispersed in a solvent, and (2) forming the sheet layer by extruding a thermoplastic resin, and the extruded thermoplastic resin It is the manufacturing method of the lamination sheet which consists of a step which bonds with the said nano fiber layer and forms a lamination sheet before solidifying.

The laminated sheet of the present invention can reliably contain a substance having a thickening action or a gelling action in the nanofiber layer due to its unique configuration, and the formation of the nanofiber layer is stabilized.
By adding a small amount of water to such a laminated sheet, the nanofiber layer can be dissolved quickly and satisfactorily, and a fluid gel-like substance can be easily formed.
In addition, by sticking this laminated sheet on the surface of an object such as human skin and moistening the laminated sheet with water, lotion, etc., the nanofiber layer is gelled, and the surface of the object is covered with water or lotion. Etc. and can be moistened.
Moreover, if a nanofiber layer and a sheet | seat layer are bonded by the extrusion laminating method, it will be excellent in shape retainability and followable | trackability.

It is a figure which shows the thickening effect of a thickening polysaccharide. The viscosity is a viscosity (mPa · s) measured by a B-type rotary viscometer when 0.5% by weight is dissolved in distilled water at 20 ° C. It is a figure which shows an example of the apparatus used for the extrusion lamination method which is a manufacturing method of the lamination sheet of this invention. 4 is a diagram showing an electron micrograph of a nanofiber layer formed in Example 3. FIG. Particles made of guar gum / xanthan gum are dispersed and entangled in fibers made mainly of polyvinylpyrrolidone (PVP).

The laminated sheet of the present invention comprises a sheet layer and a nanofiber layer provided thereon.
The sheet layer of the present invention is a sheet-like layer serving as a foundation on which the nanofiber layer is formed, and also has a role of maintaining the shape of the laminated sheet of the present invention. This sheet layer may or may not be water permeable.
Examples of the water-permeable sheet layer include mesh sheets, nonwoven fabrics, woven fabrics, knitted fabrics, fiber sheets such as paper, and laminates thereof.

Moreover, as a sheet layer which is not water-permeable, the film which consists of thermoplastic resins is mentioned, for example.
As this thermoplastic resin, for example, a polyolefin resin such as polyethylene, polypropylene or polymethylpentene resin, or a resin capable of extrusion lamination such as polystyrene, polyester resin or nylon resin can be used. In addition, graft-modified polyethylene or a copolymer of ethylene and acrylic acid or an acrylate ester may be used. Moreover, you may add fillers, such as an inorganic pigment, to this thermoplastic resin. Examples of the filler include titanium oxide, calcium carbonate, silica, talc, kaolin, carbon black, and metal powder.

As the water permeability of the water permeable sheet layer, it is generally sufficient that water permeates the sheet and oozes out to the opposite side, but the filtration time measured as follows is 1 to 300 seconds. Is preferred. In the present invention, those having a drainage time exceeding 300 seconds are not permeable, and those having a filtration time of 300 seconds or less are permeable.
Method for measuring drainage time: Using a Hertzberg filtration rate tester described in JIS P3801, the time for the amount of water passing through one water-permeable sheet to reach 100 ml is measured to obtain the drainage time (seconds).
The sheet layer is preferably peelable from the wet nanofiber layer. In order to make the sheet layer and the nanofiber layer peelable, a fiber sheet was used as the sheet layer, or the surface of paper or a synthetic resin film was subjected to a peeling treatment such as a silicone resin coating or a corona discharge treatment. A thing may be used.

The nanofiber layer of the present invention contains a water-soluble polymer and a thickening polysaccharide.
Since the nanofiber layer of the present invention is easily dissolved, at least a part of the nanofiber layer is fibrous. Although the diameter is not specifically limited, For example, it is 5 nm-50 micrometers.
The nanofiber layer of the present invention is mainly composed of a fibrous water-soluble polymer and mainly the above-mentioned thickening polysaccharide.

As a water-soluble polymer, a synthetic polymer that is soluble in an organic solvent other than water, such as polyvinyl alcohol, is used to disperse the thickening polysaccharide without dissolving it when the water-soluble polymer is mixed with the thickening polysaccharide. Polyethylene glycol, polyethylene oxide, polyacrylic acid, polymethacrylic acid, polyvinylpyrrolidone and polyacrylamide are preferred, and polyvinylpyrrolidone, polyethylene oxide, polyacrylic acid and polymethacrylic acid which are soluble in various organic solvents are more preferred. These may be used singly or in combination of two or more.
The average molecular weight of the water-soluble polymer is preferably 10,000 to 8 million, more preferably 50,000 to 6 million, and particularly preferably 100,000 to 2 million.

The polysaccharide is generally solid, and the polysaccharide is generally classified into a water-soluble polysaccharide and a water-insoluble polysaccharide (such as cellulose). In the present invention, the water-soluble polysaccharide is used.
Water-soluble polysaccharides include water-soluble mucopolysaccharides such as hyaluronic acid, pectin, xylan, glucomannan, psyllium seed gum, tamarind seed gum, gum arabic, tragacanth gum, modified corn starch, soybean water-soluble polysaccharides, alginic acid, carrageenan, laminaran, Examples include agarose and fucoidan.

In the present invention, among water-soluble polysaccharides, a thickening polysaccharide that exhibits a thickening action or a gelling action when used in water is used.
The thickening polysaccharide has, for example, a viscosity of 100 mPa · s or more, preferably 100 mPa · s or more when dissolved in distilled water at room temperature (for example, 20 ° C.) by 0.5% by weight. ˜3000 Pa · s (FIG. 1).
The thickening polysaccharide used in the present invention is a particulate solid before coming into contact with water, and may be used as it is, or may be used after pulverization. The average particle diameter is 1 to 15 μm, more preferably 2 to 10 μm, still more preferably 5 to 10 μm.
This pulverization method is not particularly limited, and examples include roller mill pulverization, jet mill pulverization, hammer mill pulverization, pin mill pulverization, rotary mill pulverization, planetary mill pulverization, attritor pulverization, and bead mill pulverization. It is done. Among these, dry jet mill pulverization is preferable from the viewpoint of preventing contamination due to abrasion of the pulverizing medium, and impingement plate type jet mill pulverization is particularly preferable even for soft particles such as polysaccharides.
The method for measuring the average particle size is not particularly limited, and for example, the average particle size is measured as the median diameter (D50) of the volume cumulative particle size distribution using a laser diffraction / scattering type (microtrack method) particle size distribution measuring device. Can do.

  Specific examples of such thickening polysaccharides include galactomannans such as guar gum, tara gum and locust bean gum, gellan gum such as chitansan gum and low acyl gellan gum (hereinafter also referred to as “LA gellan gum”), welan gum, and lamb gum gum. , Fermented polysaccharides such as diamtan gum, glucose such as starch and dextrin, cellulose derivatives such as sodium carboxymethylcellulose, hydroxyethylcellulose, hydroxypropylmethylcellulose, and oolulan. Viscous polysaccharides can also be used in the present invention.

Further, the polysaccharide thickener used in the present invention is preferably one that is soluble in cold water, for example, one that is soluble in water at 35 ° C. or lower, or one that does not dissolve in water at 35 ° C. or lower but swells. Examples of such thickening polysaccharides include galactomannans such as guar gum, tara gum and locust bean gum, fermented polysaccharides such as xanthan gum and gellan gum, and sodium carboxymethylcellulose.
Among these, galactomannans and chitansan gum are particularly preferably used in the present invention because they are composed of mannose and galactose or contain a large amount thereof, and have a high thickening effect in water (FIG. 1). As the galactomannans, guar gum, tara gum and locust bean gum are preferable.

Moreover, when the said polysaccharide mixes with another polysaccharide, salts, and other components, it may further thicken. The following examples are given as such examples.
Galactomannans increase in viscosity when used in combination with kitan sang gum or kappa-type carrageenan (κ carrageenan).
Gellan gum, carrageenan, pectin, sodium alginate and the like are thickened by mixing with divalent cations such as calcium and magnesium. Examples of such a compound containing a divalent cation include water-soluble calcium salts such as calcium chloride, calcium carbonate and calcium lactate, and magnesium salts such as magnesium chloride.
Tamarind seed gum is thickened by mixing with alcohols, glycols, glycerin, sugars, catechins and the like. For example, it is thickened by alcohols contained in lotion.

In the present invention, among these, any of the following thickening polysaccharides (1) to (3) is preferably used.
(1) Galactomannans, xanthan gum, gellan gum, or sodium carboxymethyl cellulose,
(2) A mixture of galactomannans and kitansan gum or kappa-type carrageenan,
(3) A mixture of gellan gum, carrageenan, pectin or sodium alginate and a divalent cation, wherein the cation is calcium ion or magnesium ion

This nanofiber layer can be formed by an electrospinning method. The laminated sheet of the present invention may further have a support on the nanofiber layer, and the nanofiber layer may be formed on the support by an electrospinning method.
As this support, for example, fiber sheets such as mesh sheets, nonwoven fabrics, woven fabrics, knitted fabrics, and papers, laminates thereof, and synthetic resin films such as polyolefin resins and polyester resins are used. May be. Moreover, in order to make peeling with a support body and a nanofiber layer easy, you may perform peeling processes, such as application | coating of a silicone resin, on the surface of a support body.

The electrospinning method can be performed by well-known means. Generally, a syringe is filled with a solution in which a polymer material is dissolved, and a high voltage is applied between the syringe nozzle and a conductive collector, The solution is scattered in a jet form, and the solvent is volatilized in the process of scattering, so that the fibers are deposited on the collector.
In order to form the nanofiber layer on the support, the support may be made conductive and used as it is as a collector, but the support may be placed between the nozzle and the collector.

  The conditions for performing the electrospinning method are not particularly limited, and may be appropriately adjusted according to the type of spinning solution and the use of the obtained nanofibers. As general conditions in the method of the present invention, for example, the applied voltage is 5 to 30 kV, the discharge speed is 0.01 to 1.00 mL / min, and the vertical distance between the nozzle and the substrate is 100 to 200 mm. A nozzle having a diameter of 15 to 25 G can be used. The spinning environment need not be strictly controlled, but it is preferable that the relative humidity is 10 to 50% and the temperature is 10 to 25 ° C.

  As a solvent used for the spinning solution to be subjected to the electrospinning method, a solvent that is a good solvent for the water-soluble polymer and a poor solvent for the thickening polysaccharide used in the present invention is preferably used. Alcohols are preferred as such solvents. By dissolving the water-soluble polymer using such a solvent and adding the thickening polysaccharide, a solution of the water-soluble polymer in which the thickening polysaccharide is dispersed can be obtained, and the resulting dispersion is electrospun. Spinning can be used to obtain a laminated sheet in which the polysaccharide thickener is present in the form of particles in the fiber of the water-soluble polymer. When using for cosmetics, it is preferable to use ethanol or isopropyl alcohol as a solvent from the viewpoint of safety.

The concentration of the water-soluble polymer in the spinning solution can be variously changed depending on the solvent used, the type of the water-soluble polymer and the average molecular weight, but is usually about 5 to 20% by weight. If the concentration of the water-soluble polymer is too low, no fibers are formed even if droplets scatter from the nozzle tip, and if the concentration is too high, the solution discharged from the nozzle will scatter in a jet before reaching the collector. Therefore, the fiber sheet cannot be obtained because the solution reaches the collector as it is from the nozzle or the solution is solidified at the nozzle tip and the solution is not discharged.
The addition amount of the thickening polysaccharide in the spinning solution is preferably 10 parts to 900 parts, more preferably 20 parts to 600 parts, and still more preferably 50 parts to 400 parts with respect to 100 parts by weight of the water-soluble polymer. Depending on the basis weight of the sheet, if the addition amount is 10 parts or less, sufficient thickening effect cannot be obtained even if water is added, and if it is 900 parts or more, the strength is low because there are few fibers that form the skeleton of the sheet. It becomes low and handling becomes difficult.

  The spinning solution may optionally contain a conductive agent or a surfactant. These addition amounts are usually 0.0001 to 5% by weight with respect to the spinning solution. The fiber formability can be improved by adding a conductive agent or a surfactant. As the conductive agent, a salt soluble in a solvent is preferable, and lithium salt, sodium salt, potassium salt, magnesium salt, calcium salt, aluminum salt, ammonium salt and the like can be mentioned. Further, examples of the surfactant include anionic, cationic, nonionic and amphoteric ones, but nonionic surfactants are preferred because they have little influence on spinning.

  In addition, the spinning solution includes hydrocarbons such as paraffin wax, squalane and petrolatum, natural waxes such as carnauba wax and beeswax, octyldodecyl palmitate, isopropyl myristate, glyceryl trioctanoate, stearic acid, behenic acid, etc. Fatty acids such as lanolin derivatives, amino acid derivatives, dimethylpolysiloxane, methylphenylpolysiloxane, alkyl-modified organopolysiloxane, alkoxy-modified organopolysiloxane, higher fatty acid-modified organopolysiloxane, fluorine-modified organopolysiloxane Silicone compounds such as perfluoropolyether, perfluorodecane, perfluorooctane, dextrin fatty acid ester, sucrose fatty acid ester, starch fat Oily gelling agents such as esters, aluminum isostearate and calcium stearate, UV inhibitors such as benzophenone, PABA, pacinnamic acid, salicylic acid, titanium oxide, cerium oxide, collagen peptide, silk fibroin, sodium hyaluronate , Cosmetic ingredients such as sodium salicylate, arbutin, citric acid, magnesium L ascorbate, lactoferrin, ascorbyl tetrahexyldecanoate, arbutin, gamma oryzanol, vitamin A acetate, panthenol, allantoin, betaine trimethylglycine, You may mix | blend in the range which does not inhibit the spinning by a spinning method.

The nanofiber layer and the sheet layer are preferably bonded by an extrusion laminating method.
A preferred method for producing the laminated sheet of the present invention is, for example,
(1) A nanofiber layer is made of a thick polysaccharide having a mean particle size of 1 to 15 μm and a water-soluble polymer, which is a good solvent for the water-soluble polymer and a poor solvent for the thick polysaccharide. A step of forming by electrospinning using a spinning solution dissolved or dispersed in a solvent, and (2) forming the sheet layer by extruding a thermoplastic resin, and the extruded thermoplastic resin Before solidifying, it comprises a step of bonding with the nanofiber layer to form a laminated sheet.

  An example of the apparatus used for this manufacturing method (extrusion laminating method) is shown in FIG. The thermoplastic resin injected into the hopper of the extrusion molding machine 1 and the thermoplastic resin extruded from the T-die 2 is a nanofiber layer on the support supplied from the base roll 3 by the nip roll 4 and the cooling roll 5. It is crimped to form a laminated sheet and stored in the product roll 6.

In this extrusion laminating method, the operating conditions such as the melting temperature of the resin and the laminating speed are not particularly limited as long as they are appropriately set depending on the type and apparatus of the resin used. The lamination speed is about 10 to 200 m / min. Further, it is preferable to use a nip roll having a hardness of 70 degrees or more (JIS K-6253) and pressing and pressure bonding with a linear pressure of 15 kgf / cm or more.
In addition, when two or more thermoplastic resin layers are laminated, such as when the sheet layer is formed of a plurality of thermoplastic resin layers, a plurality of extruders are used in terms of adhesion between the thermoplastic resin layers and production efficiency. It is suitable to use a method in which each thermoplastic resin is led to a respective T die in a molten state and extruded from each T die at the same time and laminated and adhered. Such a method capable of simultaneously forming a multilayer thermoplastic resin layer is called a coextrusion laminating method among the extrusion laminating methods. Further, an adhesive resin layer may be sandwiched between the thermoplastic resin layers to improve the adhesion between the resin layers. In any case, corona treatment, ozone treatment, or the like may be performed as necessary to improve the adhesion of the nanofiber layer or the thermoplastic resin.

When the laminated sheet has a support, the support may be removed from the laminated sheet after molding. Moreover, you may perform the removal of this support body at the time of product use.
The thickness of this sheet layer after cooling is usually 5 to 100 μm, preferably 10 to 60 μm.
Moreover, the basis weight of this nanofiber layer after cooling molding is usually 0.1 to 15 g / m ² . If the basis weight is less than 0.1 g / m ² , sufficient thickening effect cannot be obtained even if water is added. If the basis weight exceeds 15 g / m ² , when the support is removed from the laminated sheet, Since breakage occurs and part of the nanofiber layer remains on the support, it is not preferable.

A method of moistening the surface of an object with water or a desired lotion using the laminated sheet of the present invention includes, for example, the following steps.
(i) a step of attaching a laminated sheet to the surface of the object so that the nanofiber layer is in contact with the surface in a state where the surface of the object is moistened with water or a desired lotion;
(ii) a step of peeling the sheet layer from the laminated sheet; and
(iii) Step of maintaining this state for a certain time In any method, when the sheet layer is peeled from the laminated sheet, at least a part of the gelled nanofiber layer is formed on the surface of the object (for example, human skin). Remains.

  There is no restriction | limiting in particular as a lotion used here, What is generally used in the cosmetics field | area can be used. Examples of such skin lotions include, for example, skin moisturizing ingredients, blood circulation promoting ingredients, whitening ingredients, skin tightening ingredients, lift-up ingredients, turnover promoting ingredients and the like dissolved in water or alcohol, and optionally What mixed the emulsifier, the fragrance | flavor, the preservative, etc. is mentioned.

  The following examples illustrate the invention but are not intended to limit the invention. The viscosity was defined as the viscosity (mPa · s) measured with a B-type rotary viscometer when 0.5% by mass was dissolved in distilled water at 20 ° C. (hereinafter referred to as “0.5% viscosity”). The average particle size was measured as the median diameter (D50) of the volume cumulative particle size distribution by dispersing the polysaccharide particles in ethanol and using a laser diffraction / scattering particle size distribution measuring device (MT3300 manufactured by Nikkiso Co., Ltd.).

Example 1
2.0 g of polyvinylpyrrolidone (PVP-K90 manufactured by IPS Japan Co., Ltd., average molecular weight of 1,200,000, hereinafter referred to as “PVP”) was collected in a 100 ml vial, 18.0 g of ethanol was added, and 1 hour was added using a stirrer. The mixture was stirred to prepare a PVP ethanol solution (concentration: 10% by mass). Guar gum (SUPERGEL CSA 200/50, 0.5% viscosity 460 mPa · s, average particle size 55 μm) manufactured by Sanki Co., Ltd. was added to this PVP ethanol solution. A spinning solution for electrospinning was obtained by dispersing 2.0 g of pulverized to an average particle size of 8.7 μm using SPK-2 + DSF-2). The total solid concentration of the spinning solution is 18.2% by mass, and the mass ratio of PVP to guar gum is 1: 1.
With this spinning solution, the gauge no. An electrospinning device (NEU manufactured by Kato Tech Co., Ltd.) in which 5 g was collected in a 10 ml syringe equipped with a 24G metal non-bevel needle, and release paper (K8 Shiro P (01) manufactured by Hayashi Convertec Co., Ltd.) was fixed to the collector drum. And spinning on the release paper on the condition that the nozzle-collector distance is 10 cm, the applied voltage is 8.0 kV, the discharge speed is 20 μL / min, the collector rotation speed is 2 m / min, the traverse distance is 15 cm, and the traverse speed is 5 cm / min. A nanofiber layer of 6.0 g / m ² was formed.
Using an extrusion molding machine equipped with a T die, the nanofiber layer surface on the release paper obtained above, and low density polyethylene (LC602A manufactured by Nippon Polyethylene Co., Ltd., density 0.919 g / cm ³ , melting point 107 ° C.) So that the thickness is 30 μm at a melting temperature of 300 ° C., and is immediately pressed and pressure-bonded at a linear pressure of 15 kgf / cm by a cooling roll and a nip roll (hardness of 70 degrees). A laminated sheet having a sheet layer formed on the fiber layer was obtained.

Example 2
Guar gum was crushed from xanthan gum (KELTROL CG, manufactured by Sanki Co., Ltd., 0.5% viscosity 725 mPa · s, average particle size 108 μm) to a mean particle size of 2.7 μm using a veneer-type supersonic jet crusher. A laminated sheet was produced in the same manner as in Example 1 except that the above was changed.
Example 3
Mass ratio of guar gum pulverized to an average particle size of 8.7 μm using a collision plate type supersonic jet pulverizer and guar gum pulverized to an average particle size of 8.3 μm using a xanthan gum collision plate type supersonic jet pulverizer A laminated sheet was prepared in the same manner as in Example 1 except that the mixture was changed to a mixture (0.5% viscosity 1240 mPa · s) mixed at a ratio of 80:20.

Example 4
A laminated sheet was produced in the same manner as in Example 3 except that the mixture was changed to a mixture (0.5% viscosity 1260 mPa · s) in which guar gum and xanthan gum were mixed at a mass ratio of 65:35.
Example 5
A laminated sheet was produced in the same manner as in Example 1 except that guar gum was changed to that obtained by crushing guar gum to an average particle size of 15.0 μm using a collision plate type supersonic jet crusher.

Comparative Example 1
A laminated sheet was produced in the same manner as in Example 1 except that guar gum (average particle size 55 μm) was used as it was as guar gum.
Comparative Example 2
A laminated sheet was produced in the same manner as in Example 1 except that guar gum was changed to that obtained by crushing guar gum to an average particle size of 19.5 μm using a collision plate type supersonic jet crusher.
Comparative Example 3
The guar gum was pulverized with κ-type carrageenan (GENUVSCO CSW-2, 0.5% viscosity, 21 mPa · s, average particle size 45 μm, manufactured by Sanki Co., Ltd.) using a veneer-type supersonic jet pulverizer to an average particle size of 20 μm. A laminated sheet was produced in the same manner as in Example 1 except that it was changed to the above.

Comparative Example 4
A nanofiber layer was produced on a release paper in the same manner as in Example 1 except that guar gum (average particle size 55 μm) was used as it was as guar gum.
A roll temperature of 115 ° C. using a tabletop super calender apparatus provided with a pair of chilled rolls and resin rolls and a low-density polyethylene film (Nippon Paper Co., Ltd. one wrap) having a thickness of 30 μm as a sheet layer on the nanofiber layer. The sheet was passed so that the polyethylene film was in contact with the chilled roll under a linear pressure of 50 kgf / cm, and the nanofiber layer and the low-density polyethylene film were bonded together to obtain a laminated sheet.

Comparative Example 5
95.5 g of water was collected in a 200 ml disposable cup, and while stirring with a stirrer, guar gum (average particle size 55 μm) was added little by little to completely dissolve it, and an aqueous guar gum solution having a concentration of 0.5% by mass (0.5% viscosity) 460 mPa · s). 20.0 g of the above guar gum aqueous solution was poured into a glass petri dish having an inner diameter of 14.6 cm, dried by heating at 90 ° C., and then isolated from the glass petri dish to prepare a guar gum film serving as a nanofiber layer of 6.0 g / m ² .
A sheet layer was laminated on the nanofiber layer in the same manner as in Example 1 to produce a laminated sheet.

Evaluation (1) Dispersion stability In each Example and Comparative Example (except Comparative Example 5), the spinning solution for electrospinning was allowed to stand for 2 hours in a vial, and the dispersion stability of the particles was measured according to the following criteria. evaluated.
○: Particles do not settle and maintain a stable dispersion state.
(Triangle | delta): Although particle | grains settle partially, accumulation is not confirmed by the container bottom part.
X: Particles settle and deposit on the bottom of the container.

(2) Spinning stability In each of Examples and Comparative Examples (excluding Comparative Example 5), spinning was performed continuously for a long time using an electrospinning apparatus, and whether or not spinning was performed properly was evaluated according to the following criteria. .
○: Stable spinning is possible for 4 hours or more.
(Triangle | delta): A nozzle obstruct | occludes in 2 to 4 hours, and spinning stops.
X: The nozzle is closed within 2 hours, and spinning stops.

(3) Solubility (dissolution rate)
It was evaluated whether the nanofiber layer produced in each Example and Comparative Example dissolved quickly and completely. The nanofiber layers of each Example and Comparative Example were immersed in a large amount of distilled water and allowed to stand, and the time until the undissolved material disappeared completely was visually measured.
The solubility (dissolution rate) of the nanofiber layer was evaluated according to the following criteria.
○: Dissolves completely within 1 minute.
Δ: Completely dissolved within 1 to 5 minutes.
X: Undissolved substance remains for 5 minutes or more.

(4) Follow-up property The laminated sheet produced in each Example and Comparative Example was cut into 10 cm square, and the nanofiber layer was formed in a facial cheek part that was previously sprayed with distilled water to be about 1.0 cc by spraying and was moistened. In the state where the sheet layer was laminated, the followability to the unevenness of the skin when the nanofiber layer surface was applied was evaluated according to the following criteria.
○: Almost all of the nanofiber layer surface follows and adheres to the unevenness of the skin.
X: A part or many parts of the nanofiber layer surface follow the unevenness of the skin and do not adhere.

The evaluation results are shown in the table below.

Any of the nanofiber layers of Examples 1 to 4 were instantly dissolved at the time of solubility evaluation, became a viscous gel-like substance, and had excellent adhesion to the skin. In Example 5, a slight nozzle clogging occurred when spinning with an electrospinning apparatus, and the produced nanofiber layer had a slightly slow dissolution rate in distilled water, but a laminated sheet with good adhesion to the skin was obtained. It was.
In Comparative Example 1, since the guar gum particle size was large, the spinning solution was not stable, the nozzle was easily clogged during spinning with an electrospinning apparatus, and the solubility was poor.
In Comparative Example 2, the spinning solution was more stable and better in solubility than Comparative Example 1, but the nozzle sometimes clogged during spinning in the electrospinning apparatus.
In Comparative Example 3, in addition to the above evaluation, a moist feeling was not obtained after the sheet layer was peeled off and adhered to the wet skin.
In Comparative Example 4, the entire sheet was wrinkled during lamination, and a uniform laminated sheet could not be obtained. The low-density polyethylene film (sheet layer) contracted during bonding, peeling occurred at the interface between the nanofiber layer and the film (sheet layer), and the nanofiber layer followed the film contraction during cooling and wrinkled. It is considered a thing.
In Comparative Example 5, in addition to the poor solubility of the nanofiber layer, the guar gum film became a hard and brittle film, and when the laminated sheet was bent in the process of applying to the skin, the nanofiber layer was partially cracked. And did not follow the unevenness of the skin.

Claims (11)

A laminated sheet comprising a sheet layer and a nanofiber layer provided on the sheet layer, wherein the nanofiber layer contains a water-soluble polymer (excluding the thickening polysaccharide) and the thickening polysaccharide, A laminated sheet in which at least a part of the polysaccharide is in the form of particles having an average particle diameter of 1 to 15 μm. 2. The laminated sheet according to claim 1, wherein when the polysaccharide thickener is dissolved at 0.5% by weight in distilled water at room temperature, the viscosity by a B-type rotary viscometer is 100 mPa · s or more. The laminated sheet according to claim 1 or 2, wherein the thickening polysaccharide is any of the following (1) to (3).
(1) Galactomannans, xanthan gum, gellan gum, or sodium carboxymethyl cellulose,
(2) A mixture of galactomannans and kitansan gum or kappa-type carrageenan,
(3) A mixture of gellan gum, carrageenan, pectin or sodium alginate and a divalent cation, wherein the cation is calcium ion or magnesium ion The laminated sheet according to claim 3, wherein the galactomannans are guar gum, tara gum or locust bean gum. The laminated sheet according to any one of claims 1 to 4, wherein the water-soluble polymer is at least one selected from the group consisting of polyvinylpyrrolidone, polyethylene oxide, polyacrylic acid, and polymethacrylic acid. The laminated sheet according to any one of claims 1 to 5, wherein the sheet layer is made of a thermoplastic resin. The laminated sheet according to any one of claims 1 to 6, wherein the sheet layer is peelable from the wet nanofiber layer. The laminated sheet according to any one of claims 1 to 7, wherein the nanofiber layer is formed by an electrospinning method. The laminated sheet according to any one of claims 1 to 8, wherein the nanofiber layer and the sheet layer are bonded together by an extrusion laminating method. It is a manufacturing method of the lamination sheet according to claim 1-9,
(1) A nanofiber layer is made of a thick polysaccharide having a mean particle size of 1 to 15 μm and a water-soluble polymer, which is a good solvent for the water-soluble polymer and a poor solvent for the thick polysaccharide. A step of forming by electrospinning using a spinning solution dissolved or dispersed in a solvent, and (2) forming the sheet layer by extruding a thermoplastic resin, and the extruded thermoplastic resin A method for producing a laminated sheet comprising a step of pasting with the nanofiber layer to form a laminated sheet before solidifying. The method according to claim 9, wherein the solvent is an alcohol.