JP4464968B2 - Laminated sheet - Google Patents

Description

  The present invention relates to a multilayered (laminated) sheet that is suitable for a fiber sheet for cosmetics and body fluid absorption typified by a face mask, is gentle to the skin, easily conforms to the skin, and has excellent liquid absorbency.

  Conventionally, cotton-based materials have been widely used for cosmetic products such as face masks, and fiber sheets for absorbing body fluids such as napkins, diapers, diaper liners, and wet tissues because of their wipeability, water absorption, and dry feeling. It has been. However, even though cotton is a natural material, because of its shape and hardness, when it comes into contact with the skin, some people may experience irritation or itching, or damage the skin. Furthermore, the face mask is a fiber sheet cut into a face shape, and is used to bring out a beauty effect by being in close contact with the face and left for a while. When a cotton-based sheet is used as such a face mask, the face mask is difficult to follow along the skin, and the tendency is particularly remarkable on both sides of the nose.

As a skin care sheet or a cosmetic sheet to be brought into contact with the skin, for example, Japanese Patent Application Laid-Open No. 2003-95861 (Patent Document 1) has a cross-sectional height of 0.1 to 5 mm and a cross-sectional area of 0.01 to 200 mm ² . A skin care sheet composed of a spunlace nonwoven fabric having convex portions has been proposed. In this document, the spunlace nonwoven fabric is composed of non-pulp fibers such as synthetic fibers and fibers combining synthetic fibers with rayon or cotton, and is composed of ultrafine fibers having a fineness of 0.01 to 5.5 dtex. Nonwoven fabric is described. However, this sheet causes skin irritation and itching.

Japanese Patent Application Laid-Open No. 2003-93152 (Patent Document 2) includes an inner layer composed of a fiber assembly mainly composed of a hydrophobic component and upper and lower outer layers composed of a fiber assembly composed mainly of a hydrophilic fiber. A sheet impregnated with a cosmetic is described in an assembly having a structure of at least three layers. In this document, polyolefin fibers, polyester fibers, polyamide fibers, polyacrylonitrile fibers and polyvinyl alcohol fibers are exemplified as hydrophobic fibers constituting the inner layer, and hydrophilic functional fibers are exemplified as the hydrophilic fibers constituting the outer layer. Examples are ultrafine fibers composed of cellulose fibers having a group, alginic acid fibers, collagen fibers, and the like. However, even with this sheet, irritation to the skin is strong, and rashes and itching occur.
JP 2003-95861 A (Claim 1, paragraph numbers [0004] [0005] [0016] [0028], Tables 1 and 2) JP 2003-93152 A (Claim 1, paragraph numbers [0011] [0012] [0015])

  An object of the present invention is to provide a sheet excellent in biocompatibility and its use, which does not cause itching or rash even when it comes into contact with the skin.

  Another object of the present invention is to provide a sheet having high liquid absorbency and having high adhesion to an uneven human body such as a nose and its use.

  Still another object of the present invention is to provide a sheet that has a good touch and has a relaxing effect on the human body, and uses thereof.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors have found that a layer composed of a fiber (ethylene-vinyl alcohol copolymer-containing fiber) containing an ethylene-vinyl alcohol copolymer, and a cellulose fiber It was found that the sheet combined with the layer composed of the above has high liquid absorbency and high biocompatibility to the skin, and the present invention has been completed.

  That is, in the laminated sheet of the present invention, the second layer composed of fibers containing an ethylene-vinyl alcohol copolymer is formed on at least one surface of the first layer composed of cellulosic fibers. In the laminated sheet, the fiber containing an ethylene-vinyl alcohol copolymer is a fiber having at least a surface made of an ethylene-vinyl alcohol copolymer. The fiber containing an ethylene-vinyl alcohol copolymer may be an ethylene-vinyl alcohol copolymer fiber having an average fineness of 0.9 dtex or less. The cellulosic fiber may be rayon fiber. Furthermore, the second layer is composed of ethylene-vinyl alcohol copolymer fiber and cellulose fiber, and the ratio (mass ratio) of the two is the former / the latter = 97 / 3-60 / 40 (particularly 95/5 to 70/30). In the second layer, the ethylene-vinyl alcohol copolymer fiber may have an average fineness of 0.9 dtex or less, and the cellulose fiber may have an average fineness of 1.2 dtex or less. . In particular, in this laminated sheet, the second layer may be formed on both sides of the first layer. This laminated sheet may be comprised with the wet nonwoven fabric. In the first layer, the cellulosic fibers may be rayon fibers having an average fineness of 1.2 dtex or less. This laminated sheet may have a water absorption of 200% or more. Since this laminated sheet is excellent in touch and biocompatibility, it may be used as a sheet that can come into contact with the skin.

  The present invention also includes a face mask sheet composed of the laminated sheet. The present invention also includes a body fluid absorbing sheet composed of the laminated sheet.

  In the present invention, since a layer composed of cellulosic fibers and a layer composed of fibers containing an ethylene-vinyl alcohol copolymer on the surface are combined, itching and rash even when in contact with the skin. It does not occur and has excellent biocompatibility. In addition, it has high liquid absorbency and has high adhesion to uneven human surfaces such as the nose. Furthermore, it has a good touch and has a relaxing effect on the human body. Therefore, such a laminated sheet is suitable for a sheet that can come into contact with the skin, in particular, a face mask sheet, a body fluid absorbing sheet, and the like.

Detailed Description of the Invention

  In the laminated sheet of the present invention, the second layer composed of fibers containing an ethylene-vinyl alcohol copolymer (EVOH-containing fibers) is formed on at least one surface of the first layer composed of cellulosic fibers. Is formed.

[First layer]
In the laminated sheet of the present invention, the first layer is formed in order to improve liquid absorbency. In the first layer, as the cellulose fiber, cellulose or a derivative thereof (for example, an alkyl cellulose ether such as methyl cellulose, a hydroxyalkyl cellulose ether such as hydroxymethyl cellulose, a carboxyalkyl cellulose ether such as carboxymethyl cellulose, or a cellulose ester such as cellulose acetate) Etc.), the fiber is not particularly limited and may be a natural fiber or an artificial fiber. Examples of natural fibers include seed hair fibers such as cotton and kapok, bast fibers such as flax, cannabis, jute and ramie, and leaf vein fibers such as manila hemp and sisal hemp. Examples of artificial fibers include regenerated fibers such as rayon fibers and semi-synthetic fibers such as acetate fibers. These cellulosic fibers can be used alone or in combination of two or more. Among these cellulosic fibers, rayon fibers such as viscose rayon, copper ammonia rayon (cupra), polynosic, and lyocell (for example, registered trade name: “Tencel”) are preferable.

The first layer may further contain other fibers. Other fibers include other natural fibers, other artificial (synthetic) fibers, inorganic fibers, and the like. Examples of other natural fibers include wool (wool) and silk. Other synthetic fibers include, for example, polyamide fibers (for example, polyamide 6, polyamide 66, polyamide 11, polyamide 12, polyamide 610, polyamide 612 and other aliphatic polyamide fibers, alicyclic polyamide fibers, polyphenylene isophthalamide, etc. , Aromatic polyamide fibers such as polyhexamethylene terephthalamide and poly p-phenylene terephthalamide), polyolefin fibers (such as poly C _2-4 olefin fibers such as polyethylene and polypropylene), polyester fibers (such as , Aromatic polyester fibers such as polyethylene terephthalate, polypropylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and aliphatic polyesters such as polylactic acid Steal fiber, etc.), polyvinyl alcohol fiber, ethylene-vinyl alcohol copolymer fiber, acrylic fiber (for example, acrylonitrile fiber having an acrylonitrile unit such as acrylonitrile-vinyl chloride copolymer), polyvinyl chloride Fiber (for example, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, vinyl chloride-acrylonitrile copolymer fiber, etc.), polyvinylidene chloride fiber (for example, vinylidene chloride-vinyl chloride copolymer fiber, vinylidene chloride-acetic acid) Vinyl copolymer fiber, etc.). Examples of the inorganic fiber include glass fiber, carbon fiber, and metal fiber. These other fibers can be used alone or in combination of two or more.

  Among these other fibers, EVOH-containing fibers constituting the second layer are preferable from the viewpoints of adhesion to the second layer and biocompatibility, and polyester-based from the viewpoint of sheet characteristics and water absorption Fiber (especially hydrophilic polyester fiber) is preferred. The hydrophilic polyester fiber may be a fiber composed of a polyester resin into which a hydrophilic unit (for example, a polyoxyethylene group, a sulfonic acid group, or an amino group) is introduced.

  The ratio (mass ratio) between the cellulosic fibers and other fibers can be selected from the range of cellulosic fibers / other fibers = 100/0 to 50/50, for example, cellulosic fibers / other fibers = 100 / 0 to 60/40, preferably 100/0 to 70/30 (for example, 99/1 to 70/30), more preferably about 100/0 to 80/20 (for example, 95/5 to 80/20). There may be.

  The average fineness of the cellulosic fibers and other fibers is not particularly limited. However, in terms of flexibility and liquid retention, for example, thin fibers of 5.5 dtex or less (for example, 0.1 to 5.5 dtex), respectively. It may be. Specifically, the average fineness is, for example, 3.3 dtex or less (for example, about 0.1 to 3.3 dtex), preferably 1.2 dtex or less (for example, about 0.1 to 1.2 dtex). ), More preferably 1.1 dtex or less (for example, about 0.1 to 1.1 dtex). If the average fineness is too large, the touch and liquid absorbency are lowered, and fibers having a density of less than 0.1 dtex are difficult to produce.

  The shape of the cellulose fiber and other fibers may be a circular cross section in a cross section perpendicular to the length direction, for example, an irregular cross section (for example, an elliptical cross section, a polygonal cross section such as a tri-octagon, or a T-shape). Cross section, Y-shaped cross section, C-shaped cross section, etc.). Further, these fibers are not particularly limited in fiber length, and may be staple fibers or filament fibers. Furthermore, these fibers may be shortcut fibers such as those used as raw materials for paper, but the average fiber length is usually 1 mm or more. The fiber length of these fibers may be selected according to the layer production method. For example, when forming a nonwoven fabric by a wet method, the average fiber length is, for example, about 1 to 30 mm (particularly 2 to 20 mm). There may be. Moreover, when forming a nonwoven fabric by dry methods, such as a card method and the air lay method, average fiber length may be about 10-70 mm (especially 20-60 mm), for example. Further, these fibers may be endless long fibers when a spunbond nonwoven fabric is used. In particular, in the present invention, the average fiber length may be, for example, 1 to 20 mm, preferably 3 to 15 mm, and more preferably about 3 to 10 mm.

  The method for producing cellulosic fibers and other fibers is appropriately selected depending on the type of fiber, and is not particularly limited, and conventional methods can be used. For example, in the case of rayon fiber, it can usually be produced by a wet spinning method.

  Although the form of the 1st layer comprised with such a fiber may be any of a woven or knitted fabric and a nonwoven fabric, a nonwoven fabric is preferable from the point of flexibility and economical efficiency. The nonwoven fabric may be either a dry nonwoven fabric or a wet nonwoven fabric, but is preferably a wet nonwoven fabric from the viewpoint of interlayer adhesion in the laminated sheet. The detail of the manufacturing method of a 1st layer (fiber web) is mentioned later.

  In the first layer, a stabilizer (a heat stabilizer such as a copper compound, an ultraviolet absorber, a light stabilizer, an antioxidant, etc.), fine particles, It may contain additives such as colorants, antistatic agents, flame retardants, plasticizers, lubricants, crystallization rate retarders and the like. These additives can be used alone or in combination of two or more. These additives can be added during the production of the fiber or in subsequent steps.

The basis weight of the first layer can be selected from a range of, for example, about 5 to 100 g / m ² , and particularly preferably 10 to 60 g / m ² from the viewpoint of maintaining sufficient water absorption and imparting flexibility to the sheet. , more preferably about 12~40g / m ^2.

[Second layer]
In the fiber containing an ethylene-vinyl alcohol copolymer (EVOH-containing fiber), the ethylene-vinyl alcohol copolymer can be obtained, for example, by saponifying a copolymer of ethylene and a vinyl ester. The proportion of ethylene can be selected from the range of about 5 to 70 mol% in the copolymer, and is preferably about 20 to 65 mol% from the viewpoint of hydrophilicity and melt spinnability. Further, the proportion of ethylene is preferably 25 to 60 mol%, more preferably 27 to 55 mol% (especially 32 to 55 mol%) from the viewpoint of maintaining hydrophilicity while suppressing trouble on melt spinning due to deterioration of the staying resin. 51 mol%). If the proportion of ethylene is too large, the hydrophilicity of the resulting fiber will be insufficient and biocompatibility will deteriorate. Moreover, when there are too few ratios of ethylene, melt spinnability will deteriorate and biocompatibility will also deteriorate.

  The saponification degree of the vinyl ester component can be selected from a range of 80 mol% or more (for example, about 80 to 99.99%), and preferably 90 mol% or more (for example, 90 to 90 to 90% from the viewpoint of hydrophilicity and melt spinnability About 99.9%), more preferably 95 mol% or more (for example, about 95 to 99.8%). When the degree of saponification is too low, hydrophilicity, thermal stability, and heat resistance are lowered.

  Examples of the vinyl ester component include vinyl formate, vinyl acetate, vinyl propionate, vinyl valelate, vinyl caprate, vinyl laurate, vinyl stearate, vinyl benzoate, vinyl pivalate, vinyl versatate, and the like. . These vinyl ester components can be used alone or in combination of two or more. Of these, lower aliphatic vinyl carboxylates such as vinyl acetate and vinyl propionate are preferred, and vinyl acetate is usually used. Vinyl acetate may be used in combination with other vinyl esters (vinyl propionate, vinyl pivalate, etc.).

  The ethylene-vinyl alcohol copolymer further contains a vinyl silane compound as a copolymer component up to about 0.2 mol% in the copolymer, for example, 0.0002 to 0.2 mol% (particularly 0.0005). About 0.1 mol%). Here, examples of the vinylsilane compound include alkoxysilane compounds having a polymerizable unsaturated bond (vinyl group, allyl group, (meth) acryloyl group, etc.), such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri (β- And vinylalkoxysilanes such as methoxy-ethoxy) silane and γ-methacryloyloxypropylmethoxysilane. These vinylsilane compounds can be used alone or in combination of two or more. Of these, vinyltrimethoxysilane and vinyltriethoxysilane are preferred.

  The melt viscosity of the ethylene-vinyl alcohol copolymer is important from the viewpoint of stably producing fibers. Specifically, the MFR (measured at 190 ° C. under a load of 2160 g (about 21.2 N)) of the ethylene-vinyl alcohol-based copolymer varies depending on the form of the processing apparatus, but generally 0.05 to 500 g. / 10 minutes, preferably 0.1 to 300 g / 10 minutes, more preferably about 1 to 200 g / 10 minutes (especially 5 to 100 g / 10 minutes). If the MFR is too small, the melt spinnability is remarkably lowered. If the MFR is too large, the fiber tension during melt spinning is too low, and troubles such as yarn breakage are likely to occur.

  In the present invention, the EVOH-containing fiber is a fiber having at least a surface composed of an ethylene-vinyl alcohol copolymer, for example, a fiber composed of an ethylene-vinyl alcohol copolymer alone (an ethylene-vinyl alcohol copolymer). Polymer fiber), a composite fiber composed of an ethylene-vinyl alcohol copolymer and another synthetic resin is preferable.

In the composite fiber, examples of the other synthetic resin include the synthetic resin exemplified in the section of the synthetic fiber in the first layer. Of these synthetic fibers, polyolefin resins, polyamide resins, polyester resins and the like can be suitably used. Of these, aromatic polyester fibers (particularly poly C _2-4 alkylene arylate fibers such as polyethylene terephthalate fibers and polybutylene terephthalate fibers) are preferable from the viewpoint of sheet characteristics and versatility. The poly C _2-4 alkylene arylate fiber may be a modified poly C _2-4 alkylene arylate fiber. The modified poly C _2-4 alkylene arylate has, for example, terephthalic acid and / or 2,6-naphthalenedicarboxylic acid as a dicarboxylic acid component, and other aromatic dicarboxylic acids (for example, isophthalic acid, 5-sodium sulfone, etc.). Poly C _2-4 alkylene arylate obtained by copolymerizing copolymer components such as isophthalic acid) and aliphatic dicarboxylic acids (eg, sebacic acid, adipic acid, etc.) may also be used. The proportion of these copolymer components is about 50 mol% or less in the resin, preferably 0.1 to 30 mol%, more preferably about 0.5 to 20 mol% (particularly 1 to 10 mol%). .

  The surface of the composite fiber is composed of at least an ethylene-vinyl alcohol copolymer from the viewpoint of compatibility with the skin. Furthermore, the composite fiber is preferably a fiber in which the majority of the fiber surface (for example, 70% or more) is composed of an ethylene-vinyl alcohol copolymer, and the entire surface of the fiber is an ethylene-vinyl alcohol copolymer. A constructed fiber is particularly preferred. As the structure of the composite fiber, for example, in a cross-sectional shape in a direction perpendicular to the length direction, a core-sheath type, a sea-island type, a side-by-side type (multilayer type), a mandarin orange cross-sectional type, or a fan type (radially alternately Arrangement type) structure and the like. Of these structures, a core-sheath type composite fiber in which the entire surface of the fiber is composed of an ethylene-vinyl alcohol copolymer and the sheath component is an ethylene-vinyl alcohol copolymer fiber is preferable.

  In addition, since the ethylene-vinyl alcohol copolymer has low stability against hot water, a method of increasing the hot water resistance by acetalization or formalization of the ethylene-vinyl alcohol copolymer after fiberization is usually used. . However, in the present invention, fibers that are not acetalized or formalized are preferred from the viewpoint of compatibility with the skin.

  Of these EVOH-containing fibers, fibers composed of an ethylene-vinyl alcohol copolymer alone (ethylene-vinyl alcohol copolymer fibers) are preferred. In the ethylene-vinyl alcohol copolymer fiber, a polymer other than the ethylene-vinyl alcohol copolymer may be exposed on the fiber surface even if force is applied to the fiber surface in the fiber manufacturing process or the nonwoven fabric manufacturing process. Therefore, it has high biocompatibility. Furthermore, the manufacturing method of a fiber is also simple.

  The average fineness of the EVOH-containing fiber is not particularly limited, but is, for example, a thin fiber of 5.5 dtex or less (for example, about 0.1 to 5.5 dtex) from the viewpoint of flexibility, texture, liquid retention, and the like. There may be. Specifically, for example, 3.3 dtex or less (for example, about 0.1 to 3.3 dtex), preferably 1.1 dtex or less (for example, about 0.1 to 1.1 dtex), more preferably 0.9 dtex or less (for example, about 0.1 to 0.9 dtex). If the average fineness is too large, the touch and liquid absorbency are lowered, and fibers having a density of less than 0.1 dtex are difficult to produce.

  The shape of the EVOH-containing fiber (the shape of the entire fiber) may be a circular cross-section in a direction perpendicular to the length direction of the fiber, but may be an irregular cross-section (for example, an elliptical cross-section, a polygonal shape such as a tri-octagon) Cross section, T-shaped cross section, Y-shaped cross section, C-shaped cross section, etc.). The EVOH-containing fibers are not particularly limited in fiber length, and may be staple fibers or filament fibers. Further, the EVOH-containing fiber may be a shortcut fiber used as a raw material for paper, but the average fiber length is usually 1 mm or more. The fiber length of the EVOH-containing fiber may be selected according to the production method of the layer. For example, when forming a nonwoven fabric by a wet method, the average fiber length is, for example, about 1 to 30 mm (particularly 2 to 20 mm). There may be. Moreover, when forming a nonwoven fabric by dry methods, such as a card method and the air lay method, average fiber length may be about 10-70 mm (especially 20-60 mm), for example. Furthermore, when the EVOH-containing fiber is a spunbonded nonwoven fabric, it may be an endless long fiber. In particular, in the present invention, a wet nonwoven fabric is preferable as the nonwoven fabric form, and the average fiber length is, for example, about 1 to 20 mm, preferably 3 to 15 mm, and more preferably about 3 to 10 mm from the viewpoint of ease of papermaking. May be.

  As a method for producing the EVOH-containing fiber, a conventional melt spinning method, for example, a conventional single spinning method or a composite spinning method can be used. For example, in the composite spinning method, when producing a composite fiber composed of an ethylene-vinyl alcohol copolymer and another synthetic resin, the ethylene-vinyl alcohol copolymer and the other synthetic resin, It is also possible to melt and knead with another extruder, and then guide both polymers to the spinning head, and then discharge them from the same spinning nozzle. In this method, a mixture of an ethylene-vinyl alcohol copolymer and a plurality of other synthetic resins may be used in advance as one of the composite components.

  EVOH-containing fibers are usually used after being drawn. The drawing method may be a one-step method in which the fibers discharged from the nozzles during spinning are drawn with a godet roller, and may be drawn between hot godet rolls, or may be wound once and then hot drawn at low speed in a water bath or a hot air oven. A two-step method may be used.

  The EVOH-containing fiber may contain the additive exemplified in the first layer as necessary. These additives can be used alone or in combination of two or more. These additives can also be added during the production of the fiber or in subsequent steps. In particular, in the case of EVOH-containing fibers, it is preferable to add a trace amount of acid or a metal salt thereof to the ethylene-vinyl alcohol copolymer in order to suppress thermal deterioration during melt molding. Examples of the acid include fatty acids such as acetic acid and inorganic acids such as phosphoric acid. Examples of the metal salt include alkali metal salts and alkaline earth metal salts.

  The second layer may further contain other fibers. Other fibers include natural fibers exemplified in the first layer, other artificial (synthetic) fibers (excluding ethylene-vinyl alcohol copolymer fibers), inorganic fibers, and the like. Of these other fibers, aliphatic polyamide fibers, polyolefin fibers, cellulose fibers, polyester fibers, and the like are preferable. Of these, cellulose fibers (especially artificial fibers such as rayon fibers) are preferable from the viewpoint of controlling the absorbability and release of the aqueous liquid. When cellulosic fibers (rayon fibers) are used as the other fibers, the cellulosic fibers in the EVOH-containing fibers pass between the outer surface of the second layer (such as the contact surface with the skin) and the first layer. The aqueous liquid can be guided to the inside or the outside of the second layer. Therefore, for example, when the second layer of the laminated sheet containing an aqueous component such as lotion in the first layer is brought into contact with the skin surface, the cellulosic fibers in the EVOH-containing fiber are brought into the first layer. The absorbed lotion can be guided to the skin surface through the second layer, and body fluid on the skin surface can be guided from the second layer to the first layer. Therefore, the laminated sheet of the present invention is suitable for applications (face masks, etc.) for absorbing liquids such as body fluids and lotions. Furthermore, when the cellulose fiber of the same type (particularly the same) as the cellulosic fiber in the first layer is used as the cellulosic fiber, when the first layer and the second layer are in contact, the adhesion between both layers is improves.

  The average fineness of the other fibers is not particularly limited. However, in terms of flexibility, texture, liquid retention, etc., for example, thin fibers of 5.5 decitex or less (for example, about 0.1 to 5.5 decitex) are used. There may be. Specifically, for example, 3.3 dtex or less (for example, about 0.1 to 3.3 dtex), preferably 1.2 dtex or less (for example, about 0.1 to 1.2 dtex), more preferably 1.1 dtex or less (for example, about 0.1 to 1.1 dtex). If the average fineness is too large, the touch and liquid absorbency are lowered, and fibers having a density of less than 0.1 dtex are difficult to produce.

  About the shape and fiber length of another fiber, it is the same as that of the said EVOH containing fiber. Moreover, the additive illustrated by the 1st layer may be contained also in the other fiber as needed.

  The ratio (mass ratio) between EVOH-containing fibers and other fibers (particularly cellulosic fibers) can be selected from the range of EVOH-containing fibers / other fibers = 100/0 to 50/50, for example, EVOH-containing fibers. / Other fibers = 100/0 to 60/40, preferably 99/1 to 70/30, more preferably about 97/3 to 80/20 (especially 95/5 to 85/15). In particular, when EVOH-containing fibers such as ethylene-vinyl alcohol copolymer fibers and cellulose fibers such as rayon fibers are combined in such a ratio, there is less irritation to the skin and lotion is contained in the first layer. When an aqueous component such as, for example, is contained, the component (such as lotion) contained in the first layer can be constantly supplied to the skin surface.

  The form of the second layer composed of such fibers may be a woven or knitted fabric or a non-woven fabric, but a non-woven fabric is preferred from the viewpoint of ease of touching the human body and economy. The non-woven fabric may be either a dry non-woven fabric or a wet non-woven fabric, but a wet non-woven fabric is preferred from the viewpoint of high adhesion between laminated sheets. Further, when the nonwoven fabric is composed of EVOH-containing fibers and other fibers (cellulosic fibers or the like), the wet nonwoven fabric can mix both fibers more uniformly than the dry nonwoven fabric.

  The second layer may be a sheet produced directly from the production of fibers, such as a melt blown method or a spunbond method, or from a fiber prepared in advance, such as a dry nonwoven fabric method or a wet nonwoven fabric method. A fiber layer may be manufactured. In the case of the spunbond method, the fiber layer is drawn at the time of fiberization, whereas in the case of the melt blown method, it is hardly drawn at the time of fiberization. Sheet). Details of the method for manufacturing the second layer (fiber web) will be described later.

The basis weight of the second layer is, for example, about 5 to 100 g / m ² , preferably about 8 to 60 g / m ² , and more preferably about 10 to 40 g / m ² .

[Laminated sheet]
The laminate (multilayer structure) sheet of the present invention is a laminate sheet having a two-layer structure, which is formed of at least a first layer and a second layer, and the second layer is formed on one side of the first layer. Alternatively, a laminated sheet having three or more layers including the first layer and the second layer may be used. As a laminated sheet having three or more layers, for example, a laminated sheet in which the second layer is formed on one surface of the first layer and the third layer is formed on the other surface, the first layer A sheet in which the second layer is formed on both sides of the laminate, a laminate sheet in which the second layer is formed on both sides of the laminate of the first layer and the third layer, and the first on both sides of the third layer. Examples thereof include a laminated sheet in which a second layer is further formed on both sides of the laminate in which the layer is formed. As a fiber which comprises a 3rd layer, the fiber etc. which are different from the fiber which comprises the 1st and 2nd layer among the fibers illustrated by the term of the 1st layer are mentioned, for example.

  Among these laminated sheets, from the viewpoint of productivity and the like, a sheet in which the first layer and the second layer are in contact, that is, a laminated sheet in which the second layer is formed on one side of the first layer. A laminated sheet in which the second layer is formed on both sides of the first layer is preferable. In addition, since the first layer and the second layer are in direct contact with each other, when the first layer contains an aqueous solution such as a lotion (such as a lotion), the aqueous solution retained in the first layer ( (Such as skin lotion) is continuously released to the second layer (surface layer), giving moisturizing and refreshing feeling to the human skin.

  Furthermore, a laminated sheet in which the second layer is formed on both sides of the first layer, that is, the first layer composed of cellulosic fibers, from the viewpoint that the touch and the biocompatibility with the skin can be surely exhibited. A laminated sheet having a three-layer structure in which a second layer composed of EVOH-containing fibers is formed on both surfaces (namely, the front surface and the back surface) is particularly preferable. Such a laminated sheet is particularly preferable as a face mask sheet because both front and back surfaces can be used as surfaces in contact with the human body.

  In the laminated sheet of the present invention, each layer (the first layer and the second layer) needs to be integrated, and as a method for integrating, the binder is previously formed as a part of the fibers constituting each layer. A method of adding fibers and integrating the binder fiber as an adhesive, a method of adhering each layer with an adhesive, a method of performing an entanglement process for overlapping and integrating the layers, and thermocompression bonding with an embossing roll And a method of bonding with a sewing thread. Among these methods, a method of integrating by entanglement treatment is preferable in that flexibility can be imparted to the obtained laminated sheet. As the entanglement treatment, for example, a method of applying a high-pressure water flow to a laminated web in which a fiber web for a first layer and a fiber web for a second layer are superimposed, or the laminated web is integrated by a needle punch However, the method of applying a high-pressure water flow and integrating them is particularly preferable because a very flexible sheet can be obtained in spite of the low basis weight.

  Examples of the method for forming the fiber web constituting each layer include a dry method such as a card method and an air lay method, a wet method such as a paper making method, a spun bond method, and a melt blown method. Among the fiber webs obtained by these methods, for example, the web obtained by the wet spunlace method has a dense and uniform surface state and has a soft texture, so that it feels excellent when touching the skin. . Moreover, since the web obtained by the melt blown method is composed of ultrafine fibers, it is gentle to the skin and a soft web can be obtained. Among these methods, a wet method such as a papermaking method is preferred, and specifically, it is particularly preferred to be used in combination with the aforementioned integration method using a high-pressure water stream. That is, a preferable method is a method in which a laminate is prepared by a wet sheeting method and then integrated by applying a high-pressure water stream. When this method is used, a flexible laminate sheet with a low basis weight can be obtained. Furthermore, when the first layer of the laminated sheet is impregnated with lotion, the lotion impregnated in the first layer slowly moves to the second layer continuously, which is extremely excellent as a face mask sheet. A laminated sheet.

  In addition, in such a method, the lamination sheet comprised with the wet nonwoven fabric will be obtained. Therefore, in the method for producing a laminated sheet of the present invention, a preferred embodiment (a laminated sheet obtained by applying a high-pressure water flow to a wet nonwoven fabric of a three-layer structure composed of a second layer, a first layer, and a second layer) Specifically, the EVOH-containing fiber for the second layer (surface layer) is made up and contains water at the stage where it is made up. After stacking the cellulosic fiber layer for the first water-containing layer, and further stacking the EVOH-containing fiber layer for the second layer (back surface layer) containing water on the surface thereof , A method for producing a laminated sheet by integrating with a high-pressure water stream. By using such a method (so-called “combining” method), the fibers of the first layer and the fibers of the second layer are mixed at the interface, and an aqueous solution such as lotion is applied to the first layer. When it is contained, the lotion contained in the first layer passes through the second layer and easily moves to the surface. Furthermore, in the case of a wet nonwoven fabric, fluff fibers (for example, EVOH-containing fibers and / or cellulosic fibers) present at the interface between the first layer and the second layer assist the movement of the aqueous solution between the two layers. It becomes.

  The paper making method is generally used as a method for forming fiber webs by the wet method, but the paper making method has a higher production speed than other methods. There is an advantage that they can be mixed at any ratio. That is, the fiber form can be selected from a staple form to a pulp form, and the fiber diameter can be used from an ultrafine fiber to a thick fiber, so that the application range is very wide and a web with a good texture can be obtained.

  Furthermore, in the papermaking method, fibers obtained by melt spinning are first cut and dispersed in water, and under gentle stirring, a uniform papermaking slurry is formed. This papermaking slurry is round, long, slanted, etc. Paper making using a paper machine having at least one of these wires. Further, the wet paper obtained by such a method or the paper after drying may be entangled with the paper by applying it alone or in a laminated state. Furthermore, when making paper, the cut fibers may be beaten with a beater or refiner and then made into a papermaking slurry, and a sticky agent or a dispersant may be added during papermaking.

  The laminated sheet of the present invention has a water absorption of 200% or more (for example, 200 to 1500%), preferably 300% or more (for example, 300 to 1500%), more preferably 400% or more (for example, 400 to 1500%). Degree. In the case where the sheet is composed only of the surface layer composed of EVOH-containing fibers, such a water absorption rate cannot usually be satisfied. In order to increase the water absorption rate, the proportion of the first layer in the laminated sheet may be increased.

  The laminated sheet of the present invention can be appropriately hydrophilized and hydrophobized as necessary. Examples of the hydrophilic treatment method include graft polymerization treatment, plasma discharge treatment, corona discharge treatment, fluorine gas treatment, resin coating treatment, hydrophilic surfactant treatment, sulfonation treatment and the like.

The basis weight of the laminated sheet of the present invention is, for example, about ²⁰ to 200 g / m ² from the viewpoint of adhesion to the skin and liquid absorption, and particularly when used as a face mask sheet, preferably 30 to It is about 100 g / m ² , more preferably about 40 to 80 g / m ² .

  Since the laminated sheet of the present invention has high biocompatibility with the skin, it can be used for direct contact with the skin, for example, cosmetic products represented by face masks, surface materials such as napkins and diapers, body fluids such as diaper liners, and wet tissues. It can be used for an absorption sheet (or a skin cleaning sheet). In particular, the laminated sheet of the present invention is particularly suitable for a face mask sheet because of its high liquid absorbency and high adhesion to the uneven surface of the human body. When the laminated sheet of the present invention is used as a face mask, the laminated sheet is cut out to fit the face and impregnated with an appropriate amount of an aqueous solution in which skin care ingredients (hyaluronic acid, collagen, vitamins, etc.) are dissolved or dispersed. Obtained by.

  EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to the examples. In addition, each measured value in an Example is a value measured by the following method.

[Fiber fineness]
Measurement was performed in accordance with JIS L1013.
[Sheet thickness (mm)]
It was measured according to JIS P 8118 “Testing method for thickness and density of paper and paperboard”.

[Sheet weight of sheet (g / m ² )]
The basis weight of the sheet was measured in accordance with JIS P 8124 “Measuring basis weight of paper”.

[Moisture content of sheet (%)]
The sheet sample cut into a 10 cm square was immersed in distilled water for 2 hours, and the natural liquid was cut for 10 seconds. The weight of the test piece before treatment was W ₀ , the weight of the test piece after treatment was W _1, and the moisture content (%) was calculated by the following formula.

Moisture content (%) = (W ₁ −W ₀ ) / W ₀ × 100
Example 1
90% by mass of ethylene-vinyl alcohol copolymer fiber (manufactured by Kuraray Co., Ltd., S030, 0.7 decitex × 5 mm), rayon fiber (manufactured by Daiwabo Co., Ltd., Corona SB, 1.1 decitex × 7 mm) The papermaking slurry mixed so as to be 10% by mass was introduced into the first tank and the third tank of the three-tank machine paper machine, and 100% by mass of the rayon fiber was introduced into the second tank. The front layer and the back layer (second layer) are composed of 90% by mass of ethylene-vinyl alcohol copolymer fiber and 10% by mass of rayon fiber, and the inner layer (first layer) is 100% by mass of rayon. In addition, the three layers were drawn so as to have the same basis weight. Subsequently, three stages of water entanglement treatment of 2 MPa, 4 MPa, and 6 MPa were performed, and air-through drying was performed at 60 ° C. to obtain a laminated (multilayer structure) sheet. This laminated sheet had a basis weight of the front layer and the back layer of 20 g / m ² and a basis weight of the inner layer of 20 g / m ² . Further, in this laminated sheet, fibers in both layers were entangled at the boundary surface between the front surface layer and the inner layer and at the boundary surface between the inner layer and the back layer, and separation did not occur at the boundary surface.

  As a result of measuring the moisture content of the obtained sheet, it was 770% and the thickness was 0.44 mm. In addition, this sheet is cut into a face shape, holes or cuts are made in the portions corresponding to the eyes, mouth and nose, and skin lotion is impregnated to face 10 women suffering from atopic dermatitis for 30 minutes. I wore it as a mask and performed a wear test once a day for 10 consecutive days. As a result, all women were rated as cool, relaxed, comfortable, with less or no itching or pain. Furthermore, the face mask was in close contact with both sides of the nose, which was extremely suitable as a face mask sheet.

  From the above results, it can be seen that the laminated sheet of this example has higher biocompatibility than the cotton spunlace of Comparative Example 1 described later. Some subjects did not recognize a difference from Comparative Example 1, but none of the subjects was worse than Comparative Example 1. Moreover, it can be seen that the moisture content is high, and it is sufficient for use for retaining skin care ingredients such as a face mask.

Example 2
Using an ethylene-vinyl alcohol copolymer resin (ethylene content 44 mol, MFR 120 g / 10 min), it was blown at a die temperature of 250 ° C. to obtain a melt blown nonwoven fabric having a basis weight of about 20 g / m ² The thickness of the ethylene-vinyl alcohol-based fiber constituting the fiber was about 5 μm on average as a result of measurement with an electron microscope). On the other hand, rayon (Daiwabo Co., Ltd., Corona, 1.7 dtex x 40 mm) is 80% by mass, and hydrophilic polyester (Teijin Limited, TT04L, 1.7 dtex x 44 mm) is 20% by mass. And carded so that the basis weight was about 20 g / m ² to obtain a web. This mixed cotton web is laminated in three layers so that the melt-blown nonwoven fabric composed of an inner layer and an ethylene-vinyl alcohol copolymer resin becomes a front layer and a back layer, and subjected to a hydroentanglement treatment, and a sheet having a three-layer structure Got.

  This sheet had a water content of 860% and a thickness of 0.33 mm. As a result of performing a wearing test as a face mask in the same manner as in Example 1, as in Example 1, it was extremely excellent in adhesion to the skin, and all wearing testers were cool and excellent in a relaxed feeling. Rated as comfortable. However, this sheet was lower in strength than the sheet of Example 1, and when the folded face mask was spread, there was a sheet that broke at the place where the nose was cut.

  Moreover, as a result of using the three-layer structure sheet of the Example mentioned later as a sheet | seat which covers the scratching wound part of an atopic dermatitis patient, it was evaluated that it was excellent in the absorbability of a bodily fluid and itching decreased.

Example 3
Ethylene-vinyl alcohol copolymer resin (manufactured by Kuraray Co., Ltd., Eval E112BY, ethylene content 44 mol, MFR 12 g / 10 min) as sheath component, isophthalic acid 8 mol modified polyethylene terephthalate (isophthalate in proportion of 8 mol in resin) PET containing acid units (SV760, Kuraray Co., Ltd.) is used as the core component, spinning at 280 ° C., dry heat drawing, crimping and cutting at 80 ° C., and a core-sheath composite of 1.7 decitex × 38 mm Fiber crimped raw cotton was obtained. Using this core-sheath composite raw cotton, a web was obtained by carding so that the basis weight was about 20 g / m ² . The web of the core-sheath composite fiber is a surface layer, and the web is laminated in three layers so that the blended web of rayon and hydrophilic polyester used in Example 2 is an inner layer, and a hydroentanglement treatment is performed to form a three-layer structure. Got the sheet.

  This sheet had a water content of 880% and a thickness of 0.52 mm. Similar to Example 1, when used as a face mask for a woman suffering from atopic dermatitis, although it was less flexible than that of Example 1, the impression that it was comfortable was obtained. Moreover, the adhesiveness to the face was excellent, and both sides of the nose were also in close contact with the skin.

Comparative Example 1
A cotton spun lace with a basis weight of 60 g / m ² (manufactured by Unitika Ltd., Cotto Ace, C060S) was cut into a face mask shape and subjected to a wearing test in the same manner as in Example 1. became. Other people showed little improvement in comfort compared to before the test. Also, there were people who complained of discomfort because the skin and face mask did not adhere to both sides of the nose. This sheet had a moisture content of 1200% and a thickness of 0.37 mm.

Comparative Example 2
Using the crimped raw cotton of the core-sheath composite fiber (1.7 dtex × 38 mm) composed of the ethylene-vinyl alcohol copolymer used in Example 3 and isophthalic acid 8 mol-modified polyethylene terephthalate, the basis weight is about 60 g. The web was obtained by carding to / m ² . The web of the core-sheath composite fiber was subjected to hydroentanglement treatment to obtain a sheet. Although the thickness of this sheet was 0.48 mm, the water content was 100% and the liquid retention was insufficient, and when used as a face mask, the amount of skin water impregnated was small, and it evaporated immediately. As it was not usable.

Example 4
In Example 1, the amount of rayon fiber used for the surface layer is 20% by mass, the basis weight of the surface layer is 25 g / m ² , the basis weight of the inner layer is 25 g / m ² , and the basis weight of the back layer is 25 g / m ² . A face mask was prepared in the same manner as in Example 1 except that. When the obtained face mask was used by a woman with atopic dermatitis in the same manner as in Example 1, although it was slightly inferior to that in Example 1, an impression that it was comfortable was obtained.

Example 5
In Example 1, a laminated sheet that does not use the third tank, has two layers (ie, a surface layer and an inner layer) with no back layer, has a surface layer weight of 30 g / m ² and an inner layer of 30 g / m ^2. Manufactured. A face mask was prepared using this laminated sheet. When the obtained face mask was used by a woman with atopic dermatitis in the same manner as in Example 1, the impression that the sheet was slightly less flexible than the sheet of Example 1 but was comfortable was obtained. However, some women had the wrong side, and they could not answer that they were comfortable.

Claims (8)

A sheet selected from a face mask sheet and a body fluid absorbing sheet and used in contact with the skin, and an ethylene-vinyl alcohol-based co-polymer is formed on at least one surface of the first layer made of cellulosic fibers. A laminate in which a second layer made of a fiber containing a polymer is formed , and the fiber containing an ethylene-vinyl alcohol copolymer is at least a fiber made of an ethylene-vinyl alcohol copolymer. Sheet.   The laminated sheet according to claim 1, wherein the fiber containing the ethylene-vinyl alcohol copolymer is an ethylene-vinyl alcohol copolymer fiber having an average fineness of 0.9 dtex or less.   The laminated sheet according to claim 1, wherein the cellulosic fibers are rayon fibers.   The second layer is composed of ethylene-vinyl alcohol copolymer fibers and cellulosic fibers, and the ratio (mass ratio) of the two is the former / the latter = 97/3 to 60/40. The laminated sheet according to 1.   The second layer is composed of an ethylene-vinyl alcohol copolymer fiber having an average fineness of 0.9 dtex or less and a rayon fiber having an average fineness of 1.2 dtex or less, and the ratio (mass ratio) of both is The laminated sheet according to claim 1, wherein the former / the latter = 95/5 to 70/30.   The laminated sheet according to claim 1, wherein the second layer is formed on both surfaces of the first layer.   The laminated sheet according to claim 1, comprising a wet nonwoven fabric.   The laminated sheet according to claim 1, wherein the water absorption is 200% or more.