JP2019043103A - Laminate sheet, manufacturing method thereof, and absorptive article - Google Patents

Abstract

To provide a laminate sheet capable of preferentially diffusing a liquid in a prescribed one direction in a surface direction, a manufacturing method thereof, and an absorptive article using the laminate sheet.SOLUTION: The laminate sheet 1 has a constitution in which a cellulose fiber layer 3 containing cellulose fibers 3F is partially laminated on a substrate sheet 2 containing hydrophobic fibers 2F. The laminate sheet 1 has a hydrophobic area 4 comprising an exposed part of the substrate sheet 2 and a hydrophilic area 5 comprising an exposed part of the cellulose fiber layer 3 on at least one surface 1S1. The hydrophilic area 5 extends in one direction X and the hydrophilic area 5 and the hydrophobic area 4 adjoin in a direction Y orthogonal to the extending direction X. The substrate sheet 2 and the cellulose fiber layer 3 are bonded by entanglement of the fibers.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a laminated sheet, a method for producing the same, and an absorbent article using the laminated sheet.

  It is known to use a sheet made of non-woven fabric or pulp as a member of absorbent articles such as disposable diapers and sanitary napkins. For example, Patent Document 1 describes a surface material of a sanitary material such as a disposable diaper in which a spunbond nonwoven fabric and a thin paper are laminated, and the spunbond nonwoven fabric side is disposed in contact with the skin. . According to Patent Document 1, it is said that the body fluid is favorably transmitted through the surface material by the liquid absorbing force of the pulp fibers constituting the thin paper.

  Further, in Patent Document 2, a spunbonded nonwoven fabric having a core-sheath structure and containing fibers of a heat-fusible resin whose sheath portion has a melting point lower than that of the core portion, and continuous or discontinuous by wet papermaking on the nonwoven fabric surface A composite paper comprising a papermaking layer to be laminated is described, and the non-woven fabric and the papermaking layer are joined via the low melting point heat melting resin of the sheath portion of the spunbond non-woven fabric.

Unexamined-Japanese-Patent No. 05-176954 Japanese Patent Application Laid-Open No. 05-279997

  In absorbent articles such as disposable diapers and sanitary napkins, when excremented fluid such as urine excreted by the wearer diffuses in a direction (horizontal direction) orthogonal to the longitudinal direction (longitudinal direction) of the wearer, the excrement is discharged There is a possibility that so-called side leakage may occur, which leaks to the outside from around the legs and the like. There is a demand for a sheet-like material that can be used as a component of an absorbent article and that is effective for preventing side leakage, but there has not been provided a material that can sufficiently meet such a demand.

  Accordingly, an object of the present invention relates to a laminated sheet capable of preferentially diffusing a liquid in a predetermined one direction in a plane direction, a method of manufacturing the same, and an absorbent article using the laminated sheet.

  The present invention is a laminate sheet in which a cellulosic fiber layer containing cellulosic fibers is partially laminated on a substrate sheet containing hydrophobic fibers, and the laminate sheet is formed on at least one side of the substrate sheet. A hydrophobic region comprising an exposed portion and a hydrophilic region comprising an exposed portion of the cellulose fiber layer, the hydrophilic region extending in one direction, and the hydrophilic region in a direction orthogonal to the extending direction A hydrophobic area | region adjoins, and the said base material sheet and the said cellulose fiber layer are the lamination sheets closely_contact | adhered by the entanglement of fiber.

The present invention is a laminate sheet in which a cellulose fiber layer containing cellulose fibers is partially laminated on a substrate sheet containing hydrophobic fibers, and the laminate sheet is formed on at least one side of the substrate sheet. And a hydrophilic region comprising the exposed portion of the cellulose fiber layer, the hydrophilic region extending in one direction, and the hydrophilic region in the direction orthogonal to the extending direction It is a laminated sheet which is adjacent to the hydrophobic region, and the basis weight of the cellulose fiber layer is more than 0 g / m ^{2 and not} more than 10 g / m ² .

The present invention is also an absorbent article having the above-mentioned laminated sheet of the present invention.
In the present invention, a slurry comprising cellulose fibers is supplied to a base material sheet, and a papermaking process for partially forming a cellulose fiber layer on one side of the base material sheet by papermaking, and the paper forming process are obtained. It is a manufacturing method of a lamination sheet which has the division process of cutting the lamination sheet which carried out the non-formation position of the above-mentioned cellulose fiber layer, and dividing into plurality.

In the laminated sheet of the present invention, the liquid can be preferentially diffused in a predetermined one direction in the plane direction, and accordingly, the liquid diffusion in the direction different from the predetermined direction in the plane direction can be effectively suppressed. it can.
According to the method of manufacturing a laminated sheet of the present invention, the laminated sheet of the present invention having such liquid diffusivity can be manufactured efficiently.
The absorbent article of the present invention is excellent in the effect of preventing side leakage of excrement fluid such as urine.

FIG. 1 is a schematic plan view of an embodiment of the laminated sheet of the present invention. FIG. 2 is a schematic cross-sectional view of the I-I line cross section of FIG. FIG. 3 is a schematic plan view of another embodiment of the laminated sheet of the present invention. FIG. 4 is a plan view schematically showing the skin-facing surface, ie, the surface sheet side, of a disposable diaper as an embodiment of the absorbent article according to the present invention having the laminated sheet of the present invention. It is the top view in the unfolded state expanded flat. FIG. 5 is a schematic cross-sectional view of a cross section taken along line II-II of FIG. FIG. 6 is a schematic view showing an apparatus (wet paper machine) that can be used to carry out the method for producing a laminated sheet of the present invention. FIG. 7 is an explanatory view of a dividing step in the method for producing a laminated sheet of the present invention.

  Hereinafter, the present invention will be described based on its preferred embodiments with reference to the drawings. The lamination sheet 1 which is one Embodiment of the lamination sheet of this invention is shown by FIG.1 and FIG.2. FIG. 1 is a plan view of one surface 1S1 of both surfaces 1S1 and 1S2 of the laminated sheet 1, and FIG. 2 is a cross-sectional view along the thickness direction of the laminated sheet 1. The laminated sheet 1 has a laminated structure in which a cellulose-based fiber layer 3 containing a cellulose-based fiber 3F is partially laminated on a base sheet 2 containing a hydrophobic fiber 2F.

  The base sheet 2 is preferably composed mainly of the hydrophobic fibers 2F, and functions as a hydrophobic layer having a relatively low hydrophilicity in the laminated sheet 1. The content of the hydrophobic fibers 2F in the base sheet 2 is preferably at least 50% by mass or more, and the content may be 100% by mass. On the other hand, the cellulose-based fiber layer 3 has higher hydrophilicity than the hydrophobic fiber 2F, and is preferably mainly composed of the cellulose-based fiber 3F which is a hydrophilic fiber having a contact angle with water of less than 90 degrees measured by the following method. And function as a hydrophilic layer having relatively high hydrophilicity in the laminated sheet 1. The content of the cellulose-based fibers 3F in the cellulose-based fiber layer 3 is preferably at least 50% by mass or more, and the content may be 100% by mass. Therefore, a preferred embodiment of the laminated sheet 1 has a laminated structure in which the hydrophilic layer (the cellulose-based fiber layer 3) is partially laminated on the hydrophobic layer (the base sheet 2).

  Whether the fiber is hydrophilic or hydrophobic is judged based on the contact angle with water measured by the following method, and if the contact angle is less than 90 degrees, it is hydrophilic, in the case of 90 degrees or more If it is, it is hydrophobic. The smaller the contact angle with water measured by the following method, the higher the hydrophilicity (the lower the hydrophobicity), and the larger the contact angle, the lower the hydrophilicity (a higher hydrophobicity). In the laminated sheet 1, the hydrophobic fibers 2F constituting the substrate sheet 2 preferably have a contact angle with water of 90 degrees or more, and the cellulose-based fibers 3F constituting the cellulose-based fiber layer 3 are in contact with water The angle is preferably less than 90 degrees.

<Method of measuring contact angle>
The fiber is taken out from the object to be measured (laminated sheet), and the contact angle of water to the fiber is measured. As a measuring device, an automatic contact angle meter MCA-J manufactured by Kyowa Interface Science Co., Ltd. is used. Deionized water is used to measure the contact angle. The amount of liquid discharged from an inkjet type water droplet discharge unit (manufactured by Cluster Technology, pulse injector CTC-25 having a discharge diameter of 25 μm) is set to 20 picoliter, and the water droplets are dropped right above the fibers. The state of dropping is recorded on a high-speed recording device connected to a camera installed horizontally. From the viewpoint of later image analysis, the recording device is preferably a personal computer in which a high-speed capture device is incorporated. In this measurement, an image is recorded every 17 msec. In the recorded video, the first image of a drop of water on the fiber, attached software FAMAS (version of software is 2.6.2, analysis method is the drop method, analysis method is the θ / 2 method, image processing algorithm Image analysis is performed with no reflection, image processing image mode is frame, threshold level is 200, curvature correction is not performed, and the angle between the surface of the water droplet that touches the air and the fiber is calculated. Be a corner. The fiber removed from the object to be measured is cut into a fiber length of 1 mm, and the fiber is placed on the sample table of the contact angle meter and kept horizontal. Two different contact angles are measured per fiber. A contact angle of N = 5 is measured to one decimal place, and a value obtained by averaging a total of ten measured values (rounded to the second decimal place) is defined as the contact angle of the fiber with water. The measurement environment is room temperature 22 ± 2 ° C. and humidity 65 ± 2% RH. The smaller the contact angle value, the higher the hydrophilicity.

  When the laminated sheet is used as a component such as an absorbent article and the laminated sheet is taken out for evaluation and measurement, the component is fixed to another component by an adhesive, fusion or the like. If so, the fixed part is removed after removing the adhesive force by blowing cold air cold air or the like within a range that does not affect the contact angle of the fiber. This procedure is common to all measurements herein.

As described above, the laminated sheet 1 according to the present embodiment has a laminated structure in which the hydrophilic layer (cellulose-based fiber layer 3) is partially laminated on the hydrophobic layer (base sheet 2), In order to determine the presence or absence of such a laminated structure, first, it is necessary to determine the presence or absence of the “boundary” of each layer constituting the laminated structure. The boundary of each layer of the laminated sheet is visually identified by microscopic observation of the cross section of the sheet along the upper and lower thickness direction (direction orthogonal to the surface direction). From the shape of fibers in the sheet cross section, the space between fibers, the presence of color, thickness, a mixture other than fibers, etc., the boundary is visually recognized in the same direction because the state is clearly different in the laminated sheet upper and lower thickness direction If there is a gap or boundary that separates in the same direction, or if there is no difference in the state in the same direction, this is defined as the boundary of each layer, and it is determined that the laminated sheet has a laminated structure. .
Thus, when it is judged that the laminated sheet has a laminated structure, whether or not the laminated structure includes the hydrophobic layer and the hydrophilic layer depends on the cellulose fiber (hydrophilic fiber) and other fibers contained in each layer. The determination can be made based on the discrimination from species, the content ratio of each fiber type based on the discrimination, and the like. For identification of cellulosic fibers contained in each layer and many other fiber types, and analysis of the weight and content ratio of the identified fibers, JISL 1030-1 (Part 1 Fiber Identification), JISL 1030-2 ( The second part) The test method of the mixing rate of textile products) can be used suitably. The contact angle is measured by the above-mentioned measurement method in other fiber types other than cellulosic fibers, and those having a contact angle of 90 degrees or more are regarded as hydrophobic fibers. The content ratio of the cellulose fiber and the hydrophobic fiber in each layer can be determined by the above-mentioned JIS method. And a layer in which the content ratio of the cellulose fiber is twice or more of fibers other than the cellulose fiber is made "hydrophilic layer", and the content ratio of the hydrophobic fiber is twice or more of the cellulose fiber and other hydrophilic fibers. One layer is called "hydrophobic layer".

The basis weight of the hydrophilic layer (cellulose-based fiber layer) and the hydrophobic layer (base sheet) in the laminated sheet is measured when each layer can be isolated by delamination with a pressure-sensitive adhesive tape or the like, the weight per unit area is measured Ask for. If it can not be isolated, the thickness of each layer is measured from the photograph of the cross-sectional area of the laminated sheet, and the ratio is multiplied by the basis weight of the entire laminated sheet to determine the basis weight of each layer.
Further, the basis weight of the cellulose fiber and the hydrophobic fiber contained in each layer of the hydrophilic layer and the hydrophobic layer is calculated by multiplying the content ratio of each fiber determined by the above-mentioned JIS method by the basis weight of each layer. Ru.

  As hydrophobic fiber 2F which constitutes substrate sheet 2, a hydrophobic thermoplastic fiber (heat fusion fiber) can be used. In the base sheet 2, one of the hydrophobic fibers 2F can be used alone or in combination of two or more. As a material of the hydrophobic fiber 2F, as a hydrophobic thermoplastic resin, for example, polyolefin such as polyethylene and polypropylene; polyester such as polyethylene terephthalate; polyamide such as nylon 6 and nylon 66; polyacrylic acid, polymethacrylic acid alkyl ester, Polyvinyl chloride, polyvinylidene chloride and the like can be mentioned, and one of these may be used alone or in combination of two or more. The hydrophobic fiber 2F may be a single fiber composed of one type of synthetic resin (thermoplastic resin) or a blend polymer in which two or more types of synthetic resins are mixed, or may be a composite fiber. The composite fiber referred to here is a synthetic fiber (thermoplastic fiber) obtained by combining two or more types of synthetic resins (thermoplastic resins) having different components with a spinneret and simultaneously spinning them, and a plurality of components are respectively fibers A continuous structure in the longitudinal direction, which is mutually bonded in a single fiber. The form of the composite fiber includes a core-sheath type, a side-by-side type, and the like, and is not particularly limited. The contact angle of the hydrophobic fiber 2F with water is preferably 90 degrees or more, and more preferably 100 degrees or more.

  The form of the substrate sheet 2 is not particularly limited, and may be, for example, non-woven fabric, woven fabric (woven fabric), knitted fabric, paper, or may be a single layer structure consisting of one sheet, and a laminated structure of a plurality of sheets May be. A long-fiber non-woven fabric can be exemplified as an example of the form of the base sheet 2, and in that case, the hydrophobic fibers 2F mainly forming the long-fiber non-woven fabric are long-fibers. The term "long fiber" as used herein means a fiber having a fiber length of 30 mm or more. In particular, a so-called continuous long fiber having a fiber length of 150 mm or more is preferable in that a long fiber non-woven fabric having high breaking strength can be obtained. In addition, the upper limit of the fiber length in the said "long fiber" is not specifically limited. Further, “long-fiber non-woven fabric” typically refers to a non-woven fabric having a fiber assembly in which long-fibers are intermittently fixed by a heat fusion bond. In general, long-fiber non-woven fabrics are superior in strength to non-woven fabrics mainly composed of short fibers (short-fiber non-woven fabrics) such as air-through non-woven fabrics. As such a long fiber non-woven fabric, for example, a single layer non-woven fabric such as a spunbond non-woven fabric or a meltblown non-woven fabric, a spunbond layer mainly composed of long fibers, a laminated non-woven fabric laminated with a meltblown layer or the like, a heat roll non-woven fabric by card method, etc. Examples of the laminate non-woven fabric include spunbond-spunbond laminate non-woven fabric (SS non-woven fabric), spunbond-spunbond-spunbond laminate non-woven fabric (SSS non-woven fabric), spunbond-meltblown-spunbond laminate non-woven fabric (SMS). Nonwoven fabrics), spunbond-meltblown-meltblown-spunbond nonwoven fabrics (SMMS nonwoven fabrics) and the like.

  The content of the hydrophobic fibers 2F in the base sheet 2 is preferably 50% by mass or more, more preferably from the viewpoint of imparting sufficient hydrophobicity to the base sheet 2, with respect to the total mass of the base sheet 2. 70% by mass or more, for example, additives such as oil agents for imparting properties such as slipperiness and hydrophilicity and hydrophobicity required at the production stage of the base sheet 2 which is a nonwoven fabric, binders for maintaining strength, etc. Or less, preferably 98% by mass or less, and more preferably 90% by mass or less.

  As the cellulose-based fibers 3F constituting the cellulose-based fiber layer 3, fibers composed mainly of cellulose can be used, and for example, those used for various applications including hygiene products can be used without particular limitation. More specifically, examples thereof include natural cellulose fibers, mercerized cellulose fibers, dissolved cellulose fibers and cellulose fiber derivatives, and one of these may be used alone or in combination of two or more. Examples of natural cellulose fibers include wood pulp such as softwood pulp and hardwood pulp; cotton pulp such as cotton linters and cotton lint; non-wood pulp such as straw pulp, bagasse pulp and hemp pulp; recycled paper pulp and the like. As is well known, mercerized cellulose fibers are cellulose fibers that have been alkali-modified (so-called mercerized) by concentrated alkali treatment. As the dissolved cellulose fiber, for example, Lyocell (registered trademark), Tencel (registered trademark), Bemberg (registered trademark), viscose rayon, Benlyse (registered trademark) and the like can be mentioned. Examples of cellulose fiber derivatives include carboxymethyl cellulose, carboxyethyl cellulose, TEMPO catalyzed oxidized cellulose, methyl cellulose, ethyl cellulose and the like. The contact angle of the cellulose-based fibers 3F with water is preferably less than 70 degrees, more preferably less than 40 degrees.

  The form of the cellulose-based fiber layer 3 is not particularly limited, and may be, for example, non-woven fabric, woven fabric (woven fabric), knitted fabric, or paper. The cellulosic fiber layer 3 is typically paper and can be formed by a known wet papermaking method. However, the cellulose-based fiber layer 3 does not have to have a thickness or basis weight such that the cellulose-based fiber layer 3 can be separated from the laminated sheet 1 as, for example, a sheet of paper. That is, the cellulose-based fiber layer in the laminated sheet of the present invention may be a very thin to low basis weight layer which is difficult to separate by peeling off from the base sheet.

  The content of the cellulose fiber 3F in the cellulose fiber layer 3 is preferably 50% by mass or more based on the total mass of the cellulose fiber layer 3, from the viewpoint of imparting sufficient hydrophilicity to the cellulose fiber layer 3, More preferably, the content is 70% by mass or more, and, for example, from the viewpoint of containing a binder component for binding the cellulose fiber 3F and an agent such as wet paper strength at the production stage of the cellulose fiber layer 3 which is paper, It is 98 mass% or less, more preferably 92 mass% or less.

  The cellulose-based fiber layer 3 can contain other fiber components other than the cellulose-based fiber 3F, and examples thereof include polyolefin resins such as polyethylene and polypropylene, and polyester resins such as polyethylene terephthalate and polybutylene terephthalate. These 1 type can be used individually or in combination of 2 or more types. In addition, the cellulose fiber layer 3 can contain other components other than the fiber component, for example, paper strength enhancers such as polyamine / epichlorohydrin resin, dialdehyde starch, sponge, carboxymethyl cellulose and the like; There may be mentioned retention improvers, flocculants, pH adjusters, antibacterial agents, deodorants and flame retardants.

  The laminated sheet 1 has, on at least one side, a hydrophobic region 4 formed of the exposed portion of the base sheet 2 and a hydrophilic region 5 formed of the exposed portion of the cellulose fiber layer 3. In the laminated sheet 1 shown in FIGS. 1 and 2, the cellulose fiber layer 3 is laminated only on one side 1S1 of the laminated sheet 1, and the cellulose fiber layer 3 is not laminated on the other side 1S2. The cellulosic fiber layer 3 may be formed only on the other side 1S2, or may be formed on both sides 1S1 and 1S2. When the cellulose fiber layer 3 (hydrophilic area 5) is formed on both sides 1S1 and 1S2 of the laminated sheet 1, the arrangement pattern of the hydrophobic area 4 and the hydrophilic area 5 is the same on one side 1S1 and the other side 1S2. However, they may be different. For example, as described later, when manufacturing the laminated sheet 1 using a wet paper making method, specifically, a slurry containing the cellulose fiber 3F is supplied to the base sheet 2 to form the cellulose fiber layer 3 When the water in the slurry is strongly sucked and dewatered by suction means such as a suction box in the paper-making process, the cellulose fiber 3F can be penetrated in the thickness direction of the base sheet 2 by the suction force. A hydrophobic region 4 and a hydrophilic region 5 are present on both sides 1S1 and 1S2 of the manufactured laminated sheet 1, and their arrangement pattern is the same on one side 1S1 and the other side 1S2.

  The hydrophobic region 4 is relatively high in hydrophobicity (low in hydrophilicity) on one surface 1S1 of the laminated sheet 1 due to being formed by the base sheet 2 mainly composed of the hydrophobic fiber 2F. It is an area. In addition, the hydrophilic region 5 is formed of the cellulose fiber layer 3 mainly composed of the cellulose fiber 3F, which is a hydrophilic fiber, so that the hydrophilicity is relatively high on one surface 1S1 of the laminated sheet 1 Is a high (low hydrophobicity) region. Thus, the hydrophobic region 4 and the hydrophilic region 5 are mixed in one surface 1S1 of the laminated sheet 1. On the other hand, as shown in FIG. 2, the cellulose fiber layer 3 does not exist on the other surface 1S2 of the laminated sheet 1, and only the hydrophobic region 4 formed of the exposed portion of the base sheet 2 exists. However, in the present invention, the presence of the cellulose-based fibers 3F on the other surface 1S2 is not excluded, and the cellulose-based fibers 3F may be present on the other surface 1S2 to the extent that they do not constitute a layer. As such "a form in which a cellulose fiber is present to the extent that a layer is not formed on one side of a laminated sheet", specifically, a laminated sheet 1 manufactured by a wet papermaking method as described above, which is a cellulose based The form which the fiber 3F has penetrated in the thickness direction of the base material sheet 2 is mentioned.

  In one surface 1S1 of the laminated sheet 1, as shown in FIG. 1, the hydrophilic region 5 extends in one direction indicated by X in the figure and is orthogonal to the extending direction (longitudinal direction of the hydrophilic region 5) X In the direction (the width direction of the hydrophilic region 5) Y, the hydrophilic region 5 and the hydrophobic region 4 are adjacent to each other. More specifically, hydrophilic region 5 is in the form of a strip extending in direction X in plan view as shown in FIG. 1, and the length (width) of direction Y orthogonal to longitudinal direction X extends over the entire length in the longitudinal direction X It is constant. On one surface 1S1 of the laminated sheet 1, a plurality of hydrophilic regions 5 are intermittently arranged at equal intervals in the direction Y, and a non-arranged portion of the hydrophilic region 5 on one surface 1S1 is a hydrophobic region 4. The plurality of hydrophilic regions 5 have the same width. Also, the hydrophobic region 4 is in the form of a strip extending in the direction X in plan view as shown in FIG. 1 and is common to the hydrophilic region 5 in that the length or width of the direction Y is constant over the entire length in the longitudinal direction. However, the length of the direction Y is shorter than that of the hydrophilic region 5 and narrow.

  Thus, in one surface 1S1 of the laminated sheet 1, the hydrophobic region 4 and the hydrophilic region 5 are mixed, and the hydrophilic region 5 extends in one direction X, and the width direction Y orthogonal to the extending direction X Since the hydrophilic region 5 and the hydrophobic region 4 are adjacent to each other, the diffusivity of the aqueous liquid in the surface direction on the side of one surface 1S1 is relatively high in the extending direction X of the hydrophilic region 5 (diffusive) , The width direction Y is relatively low (difficult to diffuse). Therefore, for example, when the laminated sheet 1 is used as a component of a disposable diaper and one face 1S1 is disposed toward the wearer's skin side (the side receiving the excrement fluid first), the excretory fluid such as urine is When in contact with one surface 1S1, the waste fluid is preferentially diffused in the extending direction X while being drawn into the interior of the laminated sheet 1 (base sheet 2) by the hydrophilic region 5 and in the width direction Y Diffusion is suppressed by the hydrophobic region 4 adjacent to the hydrophilic region 5. Therefore, the laminated sheet 1 is made of a disposable diaper or the like so that the extension direction X of the hydrophilic region 5 matches the longitudinal direction of the wearer (the direction extending from the ventral side to the dorsal side through the crotch of the wearer). By arranging in the article, so-called lateral leakage in which the excrement fluid leaks to the outside from the leg surroundings and the like can be effectively prevented, and the excrement fluid can rapidly permeate the laminated sheet 1 in the thickness direction. The laminated sheet 1 has liquid permeability.

  In particular, in the laminated sheet 1, as shown in FIGS. 1 and 2, the hydrophobic regions 4 are present on both sides in the width direction Y orthogonal to the extending direction X across the one hydrophilic region 5, The diffusibility of the liquid in the width direction Y is very low, and therefore, when the laminated sheet 1 is applied to the absorbent article, lateral leakage can be more effectively prevented.

  In the laminated sheet 1, as shown in FIGS. 1 and 2, the plurality of hydrophilic regions 5 and the plurality of hydrophobic regions 4 are in the width direction Y orthogonal to the extending direction X of the plurality of hydrophilic regions 5. Since they are alternately present, they are excellent both in the property of preferentially diffusing the liquid in one direction X in the surface direction and the property of not diffusing the liquid in the direction Y orthogonal to the one direction X in the surface direction. It is difficult to diffuse the liquid quickly and to diffuse in the direction Y orthogonal to this. Therefore, when the laminated sheet 1 is applied to an absorbent article, an absorbent article can be obtained which preferentially diffuses excrement fluid such as urine in the front-rear direction of the wearer and can reliably prevent lateral leakage. In addition, since the hydrophilic regions 5 and the hydrophobic regions 4 are alternately present in the width direction Y on one surface 1S1 of the laminated sheet 1, one surface such as a laminated sheet 1A (see FIG. 3) described later, for example. Compared with the configuration in which the hydrophilic region 5 occupies most of 1S1, the dry feeling on one surface 1S1 is improved (wet feeling is reduced), and the form stability of the laminated sheet 1 at the time of water absorption is improved, It is possible to effectively prevent stagnation or twisting of the laminated sheet 1 after water absorption.

  In the laminated sheet 1, as shown in FIGS. 1 and 2, the hydrophobic regions 4 are provided at both ends in the width direction Y orthogonal to the extending direction X of the hydrophilic regions 5 on the surface 1S1 having the hydrophilic regions 5. Because it is present, liquid leakage from both ends in the width direction Y is unlikely to occur, whereby lateral leakage can be more effectively prevented when the laminated sheet 1 is applied to an absorbent article.

From the viewpoint of achieving the above-described effects more reliably, it is preferable to set the dimensions and the like of each part in the laminated sheet 1 as follows.
The length W4 (see FIG. 1) of the width direction Y orthogonal to the width or longitudinal direction (extension direction) X of one hydrophobic region 4 is preferably 1 mm or more, more preferably 10 mm or more, and preferably 80 mm or less More preferably, it is 20 mm or less.
The width W5 (see FIG. 1) of one hydrophilic region 5 is preferably 1 mm or more, more preferably 20 mm or more, and preferably 100 mm or less, more preferably 80 mm or less.
The ratio of the width W4 of one hydrophobic region 4 to the width W5 of one hydrophilic region 5 is preferably 0.05 or more, more preferably 0.5 or more, as the former (W4) / the latter (W5). Preferably it is 2 or less, More preferably, it is 1 or less.
In one surface 1S1 of the laminated sheet 1, the number of hydrophilic regions 5 present in the width direction Y is preferably 1 or more, more preferably 3 or more, and preferably 300 or less, more preferably 100 or less. . In FIG. 1, the number of hydrophilic regions 5 existing in the width direction Y is three.

  One of the features of the laminated sheet 1 is that the base sheet 2 and the cellulose-based fiber layer 3 are in close contact with each other by the entanglement of fibers. That is, the laminated adhesion form of the substrate sheet 2 and the cellulose fiber layer 3 is mainly that the hydrophobic fibers 2F of the substrate sheet 2 and the cellulose fibers 3F of the cellulose fiber layer 3 are entangled without an adhesive. It is done by However, as a result of the constituent fibers of the base sheet 2 and / or the cellulose-based fiber layer 3 having adhesiveness in the laminated adhesion form of both, in addition to the entanglement of these fibers, the fibers adhere to each other Forms are included. The above "adhesive-free" "adhesive" means an amorphous general adhesive which does not have a fiber shape. Such a laminated adhesion form of the base sheet 2 and the cellulose-based fiber layer 3 without the adhesive can be obtained by using a wet papermaking method as described later, specifically, the base sheet 2 It is obtained by forming the cellulose fiber layer 3 by supplying a slurry containing the cellulose fiber 3F.

Thus, the liquid permeability at the interface between the base sheet 2 and the cellulose fiber layer 3 is improved by the base sheet 2 and the cellulose fiber layer 3 being in close contact with each other by the entanglement of fibers without the adhesive. At the same time, the disadvantages of the use of the adhesive, for example, the decrease in water absorbency and flexibility of the laminated sheet 1 are prevented. Temporarily, when the base material sheet 2 and the cellulose fiber layer 3 are mutually bonded by the adhesive agent in the lamination sheet 1, the liquid-permeable fall in the interface of the base material sheet 2 and the cellulose fiber layer 3 is concerned about Also, it is difficult to reduce the basis weight of the cellulosic fiber layer 3. To explain the difficulty of reducing the basis weight of the latter, the method for producing such a laminate sheet 1 of the adhesive using type is obtained by overlapping the separately produced cellulose fiber layer 3 in a dry state on the dry base sheet 2. Since the cellulose-based fiber layer 3 used in such a step is required to have a certain level of strength (paper strength) so as not to break in the step, it has a step of combining and fixing with an adhesive. The fiber base layer 3 needs to have a basis weight of a certain level or more, and it is difficult to adopt a thin cellulose fiber layer 3 having a basis weight of about 1 to 7 g / m ² , for example. That is, at such a low basis weight, since the number of cellulose fibers is small and the bonding point of the fiber network can not be formed, sufficient strength (paper strength) for handling can not be obtained. In this respect, as in the present invention, if the laminated sheet 1 is in a form in which the base sheet 2 and the cellulose fiber layer 3 are in close contact with each other by entanglement of fibers without adhesive, the wet papermaking method is used as described above. By using it, the laminated sheet 1 can be manufactured without passing through the step of bonding the cellulose fiber layer 3 in a dry state, so the thin cellulose fiber layer 3 which is difficult to handle in such a bonding step, ie, It is possible to adopt a thin cellulose fiber layer 3 or a small basis weight so as not to be formed as a sheet (paper) as the cellulose-based fiber layer 3 alone, and as a result, it is possible to reduce the basis weight of the laminated sheet 1.

  The basis weight of the cellulose-based fiber layer 3 forming the hydrophilic region 5 is not particularly limited, but even if the basis weight of the base material sheet 2 forming the hydrophobic region 4 is considerably small, The effect can be exhibited, and by reducing the basis weight of the cellulose-based fiber layer 3, the liquid permeability of the laminated sheet 1 can be improved, and the basis weight of the laminated sheet 1 can be reduced. In the case where the low basis weight laminated sheet 1 is applied to, for example, an absorbent article, it may lead to an improvement in the wearing feeling and the like. In consideration of the above, the cellulose fiber layer 3 preferably has a low basis weight relative to the base sheet 2, and more specifically, the basis weight of the cellulose fiber layer 3 and the basis weight of the base sheet 2 The ratio to the amount is preferably 0.05 or more, more preferably 0.1 or more, and preferably 0.8 or less, more preferably 0.4 or less as the former / the latter.

The basis weight of the base sheet 2 is preferably 5 g / m ² or more, more preferably 8 g / m ² or more, and preferably 25 g / m ² or less, more preferably 15 g / m ² or less.
The basis weight of the cellulosic fiber layer 3 is 0 g / ^{m 2,} preferably more than 0.5 g / ^{m 2} or more, more preferably 1 g / ^{m 2} or more, and, preferably not more than 10 g / ^{m 2,} further Preferably it is 7 g / m < ² > or less, More preferably, it is 5 g / m < ² > or less.

  FIG. 3 shows a laminated sheet 1A which is another embodiment of the laminated sheet of the present invention. About the other embodiment mentioned below, the composition part different from the lamination sheet 1 mentioned above is mainly explained, the same composition part attaches the same numerals, and omits explanation. The description of the laminated sheet 1 is applied as appropriate to components that are not particularly described.

  The laminated sheet 1A shown in FIG. 3 differs from the laminated sheet 1 shown in FIG. 1 in the arrangement pattern of the hydrophobic region 4 and the hydrophilic region 5. That is, in the laminated sheet 1A, as shown in FIG. 3, the cellulose fiber layer 3 is laminated on the main part excluding one end (one side in the width direction Y) on one surface 1S1 of the laminated sheet 1A. 5 are formed, and hydrophobic regions 4 consisting of exposed portions of the base sheet 2 at both ends of the one surface 1S1, that is, at both ends of the direction Y orthogonal to the extending direction X of the hydrophilic region 5 present in the main portion. Exists. In the laminated sheet 1A, the hydrophobic regions 4 are present on both sides of the direction Y orthogonal to the extending direction X with one hydrophilic region 5 therebetween, and the hydrophilic regions 5 in the surface 1S1 having the hydrophilic regions 5 The hydrophobic regions 4 are present at both ends in the direction orthogonal to the extending direction X of the sheet, and the same effects as the laminated sheet 1 can be exhibited by having these configurations.

  The laminate sheet of the present invention including the laminate sheets 1 and 1A described above has the feature of preferentially diffusing the liquid in a predetermined one direction (the extending direction of the hydrophilic region) in the plane direction, It is suitable for various applications where the above features are utilized. In particular, the laminated sheet of the present invention is suitable as a core wrap sheet for covering a liquid-retaining absorbent core in absorbent articles such as disposable diapers and sanitary napkins, and so-called lateral leakage is more effectively prevented. obtain.

  FIGS. 4 and 5 show a deployable disposable diaper 10 which is an embodiment of the absorbent article of the present invention having the laminated sheet of the present invention. The diaper 10 has a longitudinal direction X corresponding to the longitudinal direction of the wearer and a transverse direction Y orthogonal thereto, and is wound around a liquid-retaining absorbent core 14 and the absorbent core 14 to obtain the absorbent core And 14 a core wrap sheet 15 covering the skin facing surface and the non-skin facing surface. The core wrap sheet 15 is made of the laminated sheet 1 shown in FIG.

  In the present specification, the “skin-facing surface” is a surface of the absorbent article or a component thereof (eg, core wrap sheet) that is directed to the skin side of the wearer when the absorbent article is worn, ie, relative to the wearer. It is a side close to the skin, and the "non-skin facing surface" is the surface of the absorbent article or component thereof that is directed to the side opposite to the skin side when the absorbent article is worn, ie, relatively from the wearer's skin. It is the far side. In addition, "at the time of wear" here means the state in which the normal proper wearing position, ie, the correct wearing position of the said absorbent article, was maintained.

  The diaper 10 has a crotch B and a ventral side A and a back side C extending in the longitudinal direction X from the front and back of the crotch B, and includes a liquid-retaining absorbent 13 in the crotch B. The crotch B is a portion disposed in the crotch of the wearer in the wearing state of the diaper 10, and the belly side A is the ventral side of the wearer in the wearing state of the diaper 10, that is, the longitudinal direction X of the wearer. The dorsal portion C is a portion disposed on the dorsal side of the wearer, that is, on the rear side in the longitudinal direction X, than the crotch B in the wearing state of the diaper 10.

  The diaper 10 includes a liquid-permeable top sheet 11, a liquid-impermeable or liquid-impermeable liquid-repellent or water-repellent back sheet 12 that forms a non-skin facing surface, and a liquid holding interposed between both sheets 11, 12 , And they are integrated by a known bonding means such as an adhesive. The top sheet 11 and the back sheet 12 each have a size larger than that of the absorber 13 and extend outward from the periphery of the absorber 13. The absorbent body 13 is configured to include an absorbent core 14 and a core wrap sheet 15 which covers both the outer surface of the absorbent core 14, more specifically, the skin facing surface and the non-skin facing surface. The absorbent core 14 and the core wrap sheet 15 are joined by a known joining means such as a hot melt adhesive.

  Between the top sheet 11 and the back sheet 12 in each of the ventral side A and the back side C, one or a plurality of thread-like or strip-like waist elastic members 21 are fixed in a stretched state in the lateral direction Y, Between the topsheet 11 and the backsheet 12 in the left and right leg portions disposed around the legs of the wearer, one or more thread-like or band-like leg elastic members 22 are fixed in a stretched state. Further, on the left and right side portions along the longitudinal direction X in the skin facing surface of the diaper 10, there are a pair of leakproof cuffs 16 and 16 made of liquid-proof or water-repellent and breathable leakproof cuff-forming sheets. It is provided. In the vicinity of the free end of each of the leak-barrier cuffs 16, one or more thread-like leak-barrier cuff-forming elastic members 23 are arranged in an elongated state in the longitudinal direction X. When the diaper 10 is worn, the leak-barrier cuff 16 starts from the junction of the leak-barrier cuff-forming sheet forming the leak-barrier cuff 16 with another component (for example, the back sheet 12). Stand up toward the skin side. Moreover, a pair of fastening tapes 17 and 17 are provided in the both-sides edge along the longitudinal direction X of the back side C of the diaper 10, and the non-skin opposing surface (back sheet 12) of the belly side A of the diaper 10 further. The non-skin facing surface of the cover) is provided with the attachment region 18 comprising the female member of the mechanical surface fastener, and the attachment portion comprising the male member of the mechanical surface fastener possessed by the fastening tape 17 is attached. The area 18 is made securable. As components other than the core wrap sheet 15, such as the top sheet 11, the back sheet 12, the absorbent core 14, and the leak-barrier cuff 16, those generally used in this type of absorbent article may be used without particular limitations. Can. The absorbent core 14 typically consists of a deposit of a core-forming material comprising an absorbent material, the absorbent material being, for example, a hydrophilic material such as wood pulp, synthetic fibers treated with a hydrophilizing agent, etc. Examples include fibers and water-absorbing polymer particles.

  The core wrap sheet 15 which comprises the absorber 13 which is one of the main characteristics of the diaper 10 is comprised of the lamination sheet 1 of 1 sheet, and as shown in FIG. On the non-skin opposing surface side, more specifically, between the absorbent core 14 and the back sheet 12, both side edges along the longitudinal direction X of one core wrap sheet 15 (laminated sheet 1) are overlapped. Side edge overlapping portions 20 are formed. The core wrap sheet 15 is disposed in the diaper 10 with the extension direction X of the hydrophilic region 5 in the laminated sheet 1 constituting the core wrap sheet 15 coinciding with the longitudinal direction X of the diaper 10. Therefore, the width direction Y (see FIG. 1) orthogonal to the extending direction X in the laminated sheet 1 coincides with the lateral direction Y of the diaper 10.

  The absorbent core 14 extends in the longitudinal direction X from the ventral side A through the crotch B to the dorsal side C as shown in FIG. 4 and thus covers the outer surface of the absorbent core 14 The hydrophobic area 4 and the hydrophilic area 5 of the laminated sheet 1 constituting the core wrap sheet 15 also extend in the longitudinal direction X from the belly side A through the crotch B to the back side C. Further, in the laminated sheet 1 constituting the core wrap sheet 15, as shown in FIG. 4, the plurality of hydrophilic regions 5 and the plurality of hydrophobic regions 4 are in the lateral direction orthogonal to their extending direction, that is, the longitudinal direction X. It exists alternately in Y.

  The sheet side edge overlapping portion 20 is formed at least on the crotch B on the non-skin facing surface side of the absorbent core 14. In the diaper 10, the sheet side edge overlapping portion 20 extends in the longitudinal direction X from the ventral side A through the crotch B to the dorsal side C, and as shown in FIG. It is located at the central part in the lateral direction Y.

  End overlapping portions of the core wrap sheet, such as the sheet side edge overlapping portions 20, are conventionally adopted and known in absorbent articles of this type. Generally, the end overlap portion of the core wrap sheet is formed at the lateral center of the crotch region where the amount of excretion of excretory fluid such as urine is relatively large in the absorbent article, so the excrement fluid is the end of the core wrap sheet There is a problem that when the wearer's body pressure or the like is applied to the end overlap portion of the core wrap sheet in such a state, the excretory fluid exudes therefrom and leaks to the outside.

  On the other hand, in the diaper 10, the laminated sheet 1 having the hydrophobic region 4 is adopted as the core wrap sheet 15, and the arrangement of the hydrophobic region 4 in the sheet side edge overlapping portion 20 is devised. I'm trying to solve it. That is, in the diaper 10, in the sheet side edge overlapping portion 20, the hydrophobic region 4 in one of the side edges along the longitudinal direction X of the laminated sheet 1 constituting the core wrap sheet 15 and the hydrophobic region 4 in the other are There is an overlapping hydrophobic area overlap (not shown). The said hydrophobic region overlapping part consists of a laminated structure of the base material sheet 2 which forms the hydrophobic region 4, and the cellulose fiber layer 3 which forms the hydrophilic region 5 is not distribute | arranged to this laminated structure. As described above, the presence of the hydrophobic region overlapping portion in the sheet side edge overlapping portion 20 makes it difficult to cause a state in which the excretory fluid is concentrated in the sheet side edge overlapping portion 20. The disadvantage that the excrement fluid exudes from the portion 20 and leaks from the back sheet 12 to the outside is effectively prevented.

  In order to solve the problem, at least a part of the sheet side edge overlapping portion 20 may be the hydrophobic region overlapping portion. For example, in the sheet side edge overlapping portion 20, in addition to the hydrophobic region overlapping portion, in the hydrophilic region 5 and the other in one of both side edges along the longitudinal direction X of the laminated sheet 1 constituting the core wrap sheet 15. There may be a hydrophilic region overlapping portion (not shown) in which the hydrophilic region 5 overlaps, in which case the hydrophobic region overlapping portion and the hydrophilic region overlapping portion may be adjacent in the lateral direction Y. In addition, although the said hydrophobic area | region overlapping part is what laminated | stacked only the hydrophobic area | region 4 (base material sheet 2), the said hydrophilic area | region overlapping part is the base material sheet 2 (hydrophobic area 4) and the cellulose fiber layer 3 ( Since the laminated structure with the hydrophilic region 5) is laminated, both the regions 4 and 5 coexist.

  However, from the viewpoint of more reliably preventing the above problem, it is preferable that the ratio of the hydrophobic region overlapping portion in the sheet side edge overlapping portion 20 is high, and all of the sheet side edge overlapping portion 20 overlap the hydrophobic region. It is further preferable that the hydrophilic region overlapping portion does not exist in a portion, that is, in the sheet side edge overlapping portion 20. For example, when the laminated sheet 1 (see FIG. 1) or the laminated sheet 1A (see FIG. 3) is used as the core wrap sheet 15, the hydrophobicity of one of both side edges along the longitudinal direction X in each of both sheets 1 and 1A. By overlapping only the region 4 and the other hydrophobic region 4, a sheet side edge overlapping portion 20 which includes only the hydrophobic region overlapping portion and does not have the hydrophilic region overlapping portion can be obtained.

  Hereinafter, the method for producing the laminated sheet of the present invention will be described by taking the method for producing the laminated sheet 1 as an example. FIG. 6 shows a wet paper machine 30 that can be used to make the laminated sheet of the present invention. The wet papermaking machine 30 includes a papermaking net 31, a slurry feeder 32, a press roll 35 and a Yankee dryer 37. The basic configuration of the wet paper machine 30 is the same as that of a known wet paper machine.

  The manufacturing method of the lamination sheet 1 supplies the slurry containing the cellulose fiber 3F to the base material sheet 2, and the paper making process which forms the cellulose fiber layer 3 partially on one side of this base material sheet 2 by paper forming; The laminated sheet 1 obtained through the papermaking process is cut at a predetermined position and divided into a plurality of division processes. The base sheet 2 used in such a manufacturing method is, as described above, a sheet-like material mainly composed of hydrophobic fibers (for example, all the constituent fibers are hydrophobic fibers), such as spunbonded nonwoven fabric, etc. It is a long fiber non-woven fabric. More specifically, the method for producing the laminated sheet 1 includes a dewatering step of dewatering the formed sheet 40 obtained in the paper forming step, and a drying step of drying the formed sheet 40 after the dewatering to obtain the laminated sheet 1 And a winding step of winding the obtained laminated sheet 1. The formed sheet 40 obtained in the paper making process is the laminated sheet 1 in a wet state, and the laminated sheet 1 as a product to be manufactured is one that is dewatered and dried to form a formed sheet 40 in a dried state.

  In the wet paper machine 30, as shown in FIG. 6, first, the base sheet 2 wound in a roll is continuously unrolled, and the surface to be formed with the hydrophilic region 5 (one side 1S1 of the laminated sheet 1 The sheet is placed on the paper-making net 31 with the above-mentioned side facing upward and conveyed in one direction. Then, a slurry containing the cellulose-based fibers 3 F is supplied from the slurry supply device 32 to the upper surface of the base sheet 2 on the papermaking mesh 31 during transportation, ie, the planned formation surface of the hydrophilic region 5. The cellulose fiber layer 3 is partially formed on the upper surface (paper making process). The water in the supplied slurry sequentially passes through the base sheet 2 and the papermaking mesh 31 and flows down from the lower side of the papermaking mesh 31, and the fiber components including the cellulose-based fibers 3F in the slurry are the base sheet 2 And entangle with the constituent fibers (hydrophobic fibers 2F) of the base sheet 2 and thereby partially laminate the cellulose-based fiber layer 3 containing the cellulose-based fibers 3F on one side of the base sheet 2 on the papermaking network 31 The molded sheet 40 (laminated sheet 1 in a wet state) of the above-described configuration is formed.

  In the paper making process, the slurry containing the cellulose-based fibers 3F is supplied to the entire formation planned surface of the hydrophilic region 5 of the base sheet 2, and the cellulose-based fiber layer 3 is formed on the formation planned surface It is only part of This is due to the fact that the papermaking mesh 31 supporting the base sheet 2 from the side opposite to the slurry supply side is configured to be partially different in liquid permeability. That is, the papermaking mesh 31 has a high permeability portion with relatively high liquid permeability and a low permeability portion with relatively low liquid permeability or no liquid permeability, and these both permeability portions are in the papermaking process Are arranged corresponding to the arrangement pattern of the hydrophobic region 4 and the hydrophilic region 5 in the molded sheet 40 (laminated sheet 1 in the wet state), which is an object of manufacture in the above. The highly permeable portion has extremely high permeability to water in the slurry, and due to this, in the paper making process, the fiber component in the slurry is deposited on the portion overlapping with the highly permeable portion in the base sheet 2 The fiber layer 3 (hydrophilic region 5) is formed. On the other hand, since the low permeability portion has extremely low permeability of water in the slurry or does not transmit water at all, the fiber component in the slurry in the portion overlapping the low permeability portion in the base sheet 2 in the papermaking process Is not deposited, and the substrate sheet 2 remains exposed to become the hydrophobic region 4. The highly permeable portion may be referred to as a hydrophilic region forming portion, and the low permeable portion may be referred to as a hydrophobic region formed portion. In the paper-making network 31, the plurality of low transmission parts (hydrophobic area formation parts) and the high transmission parts (hydrophilic area formation parts) respectively extend in the conveyance direction (MD; Machine Direction) of the base sheet 2 The two transparent portions alternately exist in a direction (CD; Cross machine Direction) orthogonal to the MD, and the low transparent portions exist at both ends of the CD. The liquid permeability of the papermaking mesh 31 can be adjusted by adjusting the size of a mesh (mesh) through which the liquid passes, the number of meshes per unit area, and the like. The liquid permeability can be reduced by reducing the size of the mesh and reducing the number of meshes per unit area, or by sealing with a non-liquid permeable plate, adhesive tape or the like. For example, in the case where a non-liquid-permeable plate (filler) is disposed on a part of the papermaking mesh 31, the placement site of the plate is the low-permeability portion.

  In the wet paper machine 30, as shown in FIG. 6, a suction box 33 is disposed on the opposite side to the side of the slurry supply device 32 with the paper net 31 in between, and the slurry is formed into a sheet in the paper making process. When the cellulose fiber layer 3 is formed on the material sheet 2, water in the slurry is sucked and dewatered by the suction box 33. When the suction power in suction and dewatering by the suction box 33 is increased, the cellulose-based fibers 3F in the slurry can be unevenly distributed to the paper network 31 side, and depending on the suction power and the basis weight of the base sheet 2, cellulose may be used. The system fiber 3F can be penetrated in the thickness direction of the base sheet 2. Therefore, in the case of forming the hydrophilic regions 5 on both sides 1S1 and 1S2 of the laminated sheet 1, the above-mentioned paper making process is a process of sucking and dewatering the water in the slurry containing the cellulose fiber 3F supplied to the base sheet 2 It is preferable to have

  The formed sheet 40 obtained in the paper making process is delivered from the papermaking net 31 to the belt conveyor 34 and conveyed, and is dewatered to a predetermined moisture content during the conveyance (dewatering process). In the wet paper machine 30, as shown in FIG. 6, the dewatering step is carried out by passing the formed sheet 40 between the pair of press rolls 35 while pressing. Other than such a dewatering method, a method of dewatering by suction, a method of dewatering by blowing pressurized air, and the like can be mentioned.

  The formed sheet 40 which has been subjected to the dewatering process is conveyed to the vicinity of the Yankee dryer 37 by the belt conveyor 36 and dried by being brought into contact with the surface of the Yankee dryer 37 (drying process). The drying method in the drying step is not limited to the method using such a Yankee dryer, and can be appropriately selected according to the thickness and moisture content of the molded sheet 40, the moisture content after drying, etc. For example, heating A drying method such as contact with a structure (heating element), spraying of heated air or steam (superheated steam), vacuum drying, electromagnetic wave heating, electric heating, etc. may be mentioned. Further, in the embodiment shown in FIG. 6, the dewatering and the drying of the formed sheet 40 are performed separately, but the above-described dewatering method and the drying method may be appropriately combined to carry out both steps simultaneously. The laminated sheet 1 can be obtained by dewatering and drying the formed sheet 40 as described above. In the obtained laminated sheet 1, the plurality of hydrophobic regions 4 and the plurality of hydrophilic regions 5 respectively extend in the transport direction (MD of the base sheet 2), and both the regions 4 and 5 extend in a direction perpendicular to the MD ( Alternating CD), and hydrophobic regions 4 are present at both ends of the CD. That is, the extending direction X of the hydrophobic region 4 and the hydrophilic region 5 coincides with MD, and the width direction Y orthogonal to the extending direction X coincides with CD.

  The continuous belt-like laminated sheet 1 thus obtained is taken up by the winding roll 38 and made into a roll-like wound product as shown in FIG. 7 (winding step). In addition, before winding up the lamination sheet 1 in roll shape, you may post-process a creping process etc. with respect to the lamination sheet 1 as needed.

  The laminated sheet 1 in the form of a roll as shown in FIG. 7 is cut at a cutting position indicated by a symbol CL in FIG. 7 and divided into a plurality of pieces (division step). This division process is a so-called slit process, and is a process of continuously cutting (slit) a long laminated sheet having a large width at a predetermined width. One of the main features of the method for producing a laminated sheet of the present invention is that the cut position of the laminated sheet 1 in the dividing step is a position where the cellulose fiber layer 3 (hydrophilic region 5) is not formed. In the form shown in FIG. 7, the non-forming position of the cellulose-based fiber layer 3 in the laminated sheet 1, that is, the hydrophobic region 4 which is the exposed portion of the base sheet 2 is the cutting position CL.

  The cellulose-based fiber layer 3 which is mainly paper made of cellulose-based fibers and is typically paper-made by a wet paper-making method is a planar direction compared to the base sheet 2 which is typically a long-fiber non-woven fabric. Since the fiber-to-fiber bond is weak and the fixing force with respect to the base sheet 2 is not so strong, when the laminated sheet 1 is cut at the formation position of the cellulose fiber layer 3, paper powder is easily generated and the paper generated by cutting The powder may contaminate the laminated sheet 1 and the cutting device. In particular, when the cellulose-based fiber layer 3 has a low basis weight, when the laminated sheet 1 is cut by the low-based-weight cellulose-based fiber layer 3, a large amount of paper powder is easily generated. Therefore, in the present invention, as shown in FIG. 7, the non-forming position of the cellulose-based fiber layer 3, that is, the hydrophobic region 5 which is the exposed portion of the base sheet 2, is a cutting position CL. Cut. In the embodiment shown in FIG. 7, the laminated sheet 1 is wound up and then cut (slit) at the cutting position CL (position where the cellulose fiber layer 3 is not formed), but before the laminated sheet 1 is wound up It may be cut, and the cut laminated sheet 1 may be taken up as a wound product.

  As mentioned above, although this invention was demonstrated based on the embodiment, this invention can be suitably changed, without being restrict | limited to the said embodiment. The absorbent article of the present invention is not limited to the spreadable disposable diaper as in the above embodiment, but widely includes articles used for absorbing body fluid (urine, soft stool, menstrual blood, sweat, etc.) discharged from the human body, Also included are pants-type disposable diapers, sanitary napkins, sanitary shorts, incontinence pads and the like. Further, the following appendices will be disclosed regarding the embodiment of the present invention described above.

<1>
A laminated sheet in which a cellulosic fiber layer containing cellulosic fibers is partially laminated on a base material sheet containing hydrophobic fibers,
The laminated sheet has, on at least one side, a hydrophobic area consisting of the exposed part of the substrate sheet and a hydrophilic area consisting of the exposed part of the cellulose fiber layer, the hydrophilic area extending in one direction, The hydrophilic region and the hydrophobic region are adjacent to each other in a direction orthogonal to the extending direction,
The laminated sheet in which the base sheet and the cellulose fiber layer are in close contact with each other by entanglement of fibers.
<2>
The laminated sheet according to <1>, wherein the basis weight of the cellulose fiber layer is more than 0 g / m ^{2 and not} more than 10 g / m ² .

<3>
A laminated sheet in which a cellulosic fiber layer containing cellulosic fibers is partially laminated on a base material sheet containing hydrophobic fibers,
The laminated sheet has, on at least one side, a hydrophobic area consisting of the exposed part of the substrate sheet and a hydrophilic area consisting of the exposed part of the cellulose fiber layer, the hydrophilic area extending in one direction, The hydrophilic region and the hydrophobic region are adjacent to each other in a direction orthogonal to the extending direction,
The basis weight of the cellulosic fiber layer, 0 g / ^{m 2} Ultra 10 g / ^{m 2} or less is laminated sheet.
<4>
The laminated sheet according to <3>, wherein the base sheet and the cellulosic fiber layer are in close contact with each other by entanglement of fibers.

<5>
The laminated sheet according to any one of <1> to <4>, wherein the hydrophobic regions are present on both sides of one of the hydrophilic regions and in a direction orthogonal to the extending direction.
<6>
The laminated sheet according to any one of <1> to <5>, wherein the plurality of hydrophilic regions and the plurality of hydrophobic regions are alternately present in a direction orthogonal to the extending direction of the plurality of hydrophilic regions. .
<7>
In any one of the above <1> to <6>, the hydrophobic region is present at both ends of the laminated sheet in the direction orthogonal to the extending direction of the hydrophilic region on the surface having the hydrophilic region. Laminated sheet.
<8>
Content of the said cellulose-based fiber in the said cellulose-based fiber layer is 50 mass% or more, The lamination sheet of any one of said <1>-<7> which may be 100 mass%.
<9>
The hydrophobic fiber has a contact angle with water of 90 degrees or more, and the hydrophilic fiber has a contact angle with water of less than 90 degrees according to any one of <1> to <8>. Laminated sheet.
<10>
The lamination sheet of any one of said <1>-<9> whose contact angle with the water of the said hydrophobic fiber is 100 degree | times or more.
<11>
The laminated sheet according to any one of <1> to <10>, wherein the contact angle of the cellulose-based fiber with water is less than 70 degrees, preferably less than 40 degrees.

<12>
The hydrophobic fiber comprises a hydrophobic thermoplastic resin,
The thermoplastic resin is at least one selected from the group consisting of polyolefin, polyester, polyamide, polyacrylic acid, polymethacrylic acid alkyl ester, polyvinyl chloride and polyvinylidene chloride,
The laminated sheet according to any one of <1> to <11>, wherein the polyolefin contains polyethylene and polypropylene, the polyester contains polyethylene terephthalate, and the polyamide contains nylon 6 and nylon 66.
<13>
The laminated sheet according to any one of <1> to <12>, wherein the base sheet is a long fiber non-woven fabric.
<14>
The lamination sheet of any one of said <1>-<13> in which the said cellulose fiber layer is laminated | stacked only on one side of the said lamination sheet.
<15>
The laminated sheet according to any one of <1> to <14>, wherein the hydrophobic region has a short length in a direction orthogonal to the extending direction as compared with the hydrophilic region.
<16>
The laminated sheet according to any one of <1> to <15>, wherein the base sheet and the cellulose fiber layer are in close contact with each other without an adhesive.
<17>
The laminated sheet according to any one of <1> to <16>, wherein the cellulose-based fiber layer has a small thickness or a small basis weight such that the cellulose-based fiber layer is not formed as a single sheet of paper.

<18>
The ratio of the basis weight of the cellulose-based fiber layer to the basis weight of the base sheet is 0.05 or more and 0.8 or less, preferably 0.1 or more, and preferably 0 or less as the former / the latter. The lamination sheet of any one of said <1>-<17> which is 4 or less.
<19>
The ratio between the basis weight of the cellulose-based fiber layer and the basis weight of the substrate sheet is, as the former / the latter, 0.1 or more and 0.4 or less in any one of the above <1> to <18> Description laminated sheet.
<20>
The basis weight of the cellulose-based fiber layer is 0.5 g / m ² or more and 7 g / m ² or less, preferably 1 g / m ² or more, and preferably 5 g / m ² or less. The laminated sheet of any one of 19>.
<21>
The laminated sheet according to any one of <1> to <20>, wherein the basis weight of the cellulose-based fiber layer is 1 g / m ² or more and 5 g / m ² or less.

<22>
The absorbent article which has a lamination sheet of any one of said <1>-<21>.
<23>
A liquid-retaining absorbent core having a longitudinal direction corresponding to the front-rear direction of the wearer and a transverse direction orthogonal thereto, wound around the absorbent core, and the skin-facing surface and the non-skin facing of the absorbent core And a core wrap sheet covering the surface, and on the non-skin-facing surface side of the absorbent core, both side edges along the longitudinal direction of the core wrap sheet overlap to form a sheet side edge overlapping portion Yes,
The core wrap sheet is the laminated sheet, and the extending direction of the hydrophilic region in the laminated sheet coincides with the longitudinal direction,
The absorption according to <22>, wherein a hydrophobic region overlapping portion in which the hydrophobic region at one of both side edges of the core wrap sheet overlaps the hydrophobic region at the other is present at the sheet side edge overlapping portion. Sex goods.
<24>
The absorbent article as described in said <22> or <23> whose whole of the said sheet | seat side edge part overlapping part is the said hydrophobic area | region overlapping part.

<25>
It is a manufacturing method of the lamination sheet of any one of said <1>-<21>, Comprising:
A sheet-forming step of supplying a slurry containing the cellulose-based fiber to a base material sheet and partially forming a cellulose-based fiber layer on one side of the base material sheet by sheet-forming;
The manufacturing method of the lamination sheet which has the division process of cutting the above-mentioned lamination sheet obtained through the above-mentioned paper-making process in the non-formation position of the above-mentioned cellulose fiber layer, and dividing into plurality.
<26>
A sheet-forming step of supplying a slurry containing cellulose-based fibers to a substrate sheet, and partially forming a cellulose-based fiber layer on one side of the substrate sheet by sheet-forming;
The manufacturing method of the lamination sheet which has the division process of cutting the lamination sheet obtained through the above-mentioned paper-making process in the non-formation position of the above-mentioned cellulose fiber layer, and dividing into plurality.
<27>
In the paper-making step, water in the slurry supplied to the base sheet is sucked and dewatered by a suction means to penetrate the cellulose-based fibers contained in the slurry in the thickness direction of the base sheet. The manufacturing method of the lamination sheet as described in> or <26>.
<28>
In the paper making process, the slurry is supplied to the substrate sheet placed on the papermaking mesh from the side opposite to the papermaking mesh;
The papermaking net is configured such that liquid permeability is partially different, and a plurality of portions whose liquid permeability is different from one another are obtained by passing through the paper making process to the hydrophobic area and the hydrophilic area of the laminated sheet. The manufacturing method of the lamination sheet of any one of said <25>-<27> arrange | positioned corresponding to arrangement | positioning pattern.
<29>
In the laminated sheet obtained through the papermaking process, the plurality of hydrophobic regions and the hydrophilic regions extend in the transport direction (MD) of the base sheet, and both the regions 4 and 5 are MD The manufacturing method of the lamination sheet of any one of said <25>-<28> in which it exists in the direction (CD) orthogonal to, and this hydrophobic area | region exists in the both ends of CD.
<30>
The basis weight in the dry state of the cellulose-based fiber layer in the laminated sheet obtained through the paper-making process is more than 0 g / m ^{2 and} 10 g / m ² or less, preferably 0.5 g / m ² or more, and further The method for producing a laminated sheet according to any one of the above <25> to <29>, which is preferably 1 g / m ² or more, and preferably 7 g / m ² or less, more preferably 5 g / m ² or less. .
<31>
The basis weight in the dry state of the cellulose-based fiber layer in the laminated sheet obtained through the paper-making process is any one of <25> to <30>, which is 1 g / m ^{2 to} 5 g / m ^2. The manufacturing method of the lamination sheet as described in a term.

  Hereinafter, the present invention will be more specifically described by way of examples, but the present invention is not limited to such examples.

[Examples 1 to 3]
The laminated sheet was manufactured using a general-purpose wet paper machine. Specifically, a cellulose fiber (fiber concentration 0.1 mass%), a wet paper strength agent (trade name "WS-4030", manufactured by Hoshimitsu PMC Co., Ltd.) 0.5 mass% (vs. cellulose fiber) Was uniformly dispersed in water to prepare a slurry (stock). The cellulose fiber was fibrillated by a beating machine and used as having a freeness of 650 mL. Next, a base sheet of 300 mm in width (length of CD) is placed on a wire mesh paper wire with a wire opening diameter of 90 μm (166 mesh), and the slurry is dispersed on the upper surface of the base sheet to By partially forming a cellulose fiber layer having a predetermined basis weight on one side of the material sheet, a hydrophobic area consisting of the exposed part of the substrate sheet and a hydrophilic area consisting of the exposed part of the cellulose fiber layer A molded sheet having the The formed sheet was dewatered using a suction box and a press roll, and then pressed against the surface of the Yankee dryer and dried to obtain a laminated sheet with a width of 260 mm.
In each of the laminated sheets of Examples 1 to 3 thus obtained, the hydrophobic region and the hydrophilic region respectively extend in the MD, both regions alternately exist in the CD, and the hydrophobic regions are on both ends of the CD. Exists. The arrangement pattern of both areas in the laminated sheet of Examples 1 to 3 is in the same stripe shape as that of the laminated sheet 1 shown in FIG. 1, and in terms of the number of both areas and the CD length (width) It is different.

Softwood bleached kraft pulp (NBKP) (trade name "Caribbean", manufactured by Cariboo Pulp and Paper) was used as the cellulose-based fiber in the production of the laminated sheet of Examples 1 to 3. As the substrate sheet, a spunbond nonwoven fabric (long fiber nonwoven fabric) having a basis weight of 9 g / m ² and having hydrophobic fibers made of polypropylene resin as constituent fibers was used. As the wire mesh papermaking wire, one having the liquid permeability adjusted corresponding to the pattern of the hydrophobic area and the hydrophilic area was used. The papermaking speed at the time of wet papermaking was 10 m / min.

[Reference example]
The base material sheet (spun bonded nonwoven fabric) which comprises the lamination sheet of Examples 1-3 was made into the reference example as it was.

Comparative Example
A laminated sheet was manufactured as a comparative example in the same manner as in Examples 1 to 3 except that a cellulose-based fiber layer was formed on the entire area of one surface of the substrate sheet and the entire one surface was made a hydrophilic region.

[Evaluation test 1]
The side leakage prevention was evaluated by the following method about each Example and a reference example and a comparative example. The results are shown in Table 1 below.

<Method of evaluating side leakage prevention>
One square of 15 cm square is cut out from the sheet to be evaluated to obtain a sample. The sample is secured in a stretched state using adhesive tape on a flat acrylic plate without irregularities. When the cellulose fiber layer is formed on the surface of the sample, the sample is fixed to the plate with the surface on which the cellulose fiber layer is formed facing up. 10 g of artificial urine is dropped over the sample from directly above the center of the sample over 3 seconds, and within 20 seconds after the end of dropping, the artificial urine is not absorbed by the sample but overflows and diffuses on the surface Observe. At this time, the maximum length (horizontal length, the direction orthogonal to the extending direction of the hydrophilic fiber layer) of the diffusion portion (liquid diffusion portion) of the artificial urine on the surface of the sample and the maximum length direction at that moment are orthogonal Measure the length in the direction (longitudinal length) and calculate their ratio (aspect ratio; longitudinal length / horizontal length). As the aspect ratio is larger, the liquid is preferentially diffused in a predetermined one direction (the maximum length direction) in the surface direction of the sample, and the liquid is less likely to be diffused in the direction orthogonal to the one direction. It is judged to be excellent, and it is highly rated.
For example, as in Examples 1 to 3, when the cellulose fiber layer extends in one direction on the dropping surface (liquid receiving surface) of the artificial urine in the sample, the cellulose fiber layer is artificial in the extending direction of the cellulose fiber layer Urine preferentially diffuses to form a liquid diffusion portion having an elliptical shape in plan view, so the length of the liquid diffusion portion in the extending direction becomes the longitudinal length, and is orthogonal to the extending direction of the liquid diffusion portion The length in the width direction is the horizontal length.
The composition of artificial urine is as follows: urea 1.94% by mass, sodium chloride 0.7954% by mass, magnesium sulfate (heptahydrate) 0.11058% by mass, calcium chloride (dihydrate) 0. 06208 mass%, potassium sulfate 0.19788 mass%, polyoxyethylene lauryl ether 0.0035 mass% and deionized water (remaining amount).

As shown in Table 1, in each Example, since the hydrophilic area and the hydrophobic area are mixed in a predetermined pattern on the liquid receiving surface, the aspect ratio of the liquid diffusion portion largely exceeds 1, that is, the cellulose fiber While the liquid was diffused preferentially in the extending direction of the layer (hydrophilic region), it was difficult to diffuse the liquid in the direction orthogonal to the extending direction. Therefore, when the laminate sheet of each example is applied to an absorbent article such as a disposable diaper so that the extending direction of the hydrophilic region in the laminate sheet matches the longitudinal direction (longitudinal direction) of the wearer, It is surmised that side leakage is effectively prevented.
On the other hand, in the reference example and the comparative example, since only one of the hydrophilic region and the hydrophobic region is present on the liquid receiving surface, the aspect ratio of the liquid diffusion portion is close to 1 and the liquid is preferentially given in a predetermined direction. It was poor in the ability to diffuse.

[Test Examples 1 to 3]
According to the method for producing laminated sheets of Examples 1 to 3, using the same raw material as the production method, a cellulose fiber layer (hydrophilic region) having a predetermined basis weight all over one surface (hydrophobic region) of the substrate sheet To produce a laminated sheet. Two 5 cm square shapes were cut out from the produced laminated sheet, and the two sheets were superimposed so that the cellulose fiber layer was the upper layer and the base sheet was the lower layer (Test Examples 2 and 3). Separately, a square sample of 5 cm square was cut out and overlapped from the base sheet to obtain a sample (Test Example 1).
[Evaluation test 2]
The exudation prevention property was evaluated by the following method about each reference example. The results are shown in Table 2 below. The purpose of the exudation prevention property is to evaluate the extent of exudation of liquid from the overlapping portion of the side edge of the sheet when the sample is used as a core wrap sheet in an absorbent article.

<Evaluation method of exudation prevention property>
Place a basis weight 200 g / m ² pulp sheet on a bench, placed in a state of spread samples over the pulp sheet, on top of the sample, the tube inner diameter 25 mm, acrylic cylinder of cylinder height 50mm The acrylic injection plate, which is integrally formed so as to be positioned on the 10 mmφ injection opening, is placed one on top of the other so that the injection hole is located at the center of the sample, and an appropriate weight plate is placed Adjust the load (including the injection plate itself) to 1 kPa. 10 mL of physiological saline (0.9% by mass sodium chloride aqueous solution) is poured at once into the cylinder of the injection plate, and from the moment when the pouring is over, the physiological saline in the cylinder disappears and the surface of the sample is exposed Measure the time (sec / 10 mL) and let it be the liquid permeation time. The measurement is performed three times for each sample, and the average value is taken as the liquid permeation time of the sample. As the liquid permeation time is longer, it is judged that bleeding of the liquid from the overlapping portion at the side edge of the sheet when used as a core wrap sheet is less likely to occur, and the evaluation is highly evaluated.

  As shown in Table 2, in Test Example 1 in which two base sheets (hydrophobic regions) were stacked, a test in which two laminated sheets in which a cellulosic fiber layer (hydrophilic region) was stacked on the entire surface of the base sheet was stacked. As compared with Examples 2 and 3, the liquid permeation time was longer and the exudation prevention property of the liquid was excellent. Therefore, when a laminated sheet in which a cellulose-based fiber layer is partially laminated on one surface of a base sheet is used as a core wrap sheet in an absorbent article, reference is made to the sheet side edge overlap of the core wrap sheet. It can be seen that it is preferable to have a hydrophobic region overlapping portion in which only the hydrophobic regions overlap one on top of the other.

1,1A laminated sheet 1S1,1S2 laminated sheet surface 2 base sheet 2F hydrophobic fiber 3 cellulose fiber layer 3F cellulose fiber 4 hydrophobic area 5 hydrophilic area 10 disposable diaper (absorbent article)
11 top sheet 12 back sheet 13 absorber 14 absorbent core 15 core wrap sheet (laminated sheet)
Reference Signs List 20 sheet side edge overlapping portion 30 wet paper machine 31 papermaking net 32 slurry supply device 33 suction box 34, 36 belt conveyor 35 press roll 37 yanky dryer 38 winding roll 40 formed sheet

Claims (8)

A laminated sheet in which a cellulosic fiber layer containing cellulosic fibers is partially laminated on a base material sheet containing hydrophobic fibers,
The laminated sheet has, on at least one side, a hydrophobic area consisting of the exposed part of the substrate sheet and a hydrophilic area consisting of the exposed part of the cellulose fiber layer, the hydrophilic area extending in one direction, The hydrophilic region and the hydrophobic region are adjacent to each other in a direction orthogonal to the extending direction,
The laminated sheet in which the base sheet and the cellulose fiber layer are in close contact with each other by entanglement of fibers. A laminated sheet in which a cellulosic fiber layer containing cellulosic fibers is partially laminated on a base material sheet containing hydrophobic fibers,
The laminated sheet has, on at least one side, a hydrophobic area consisting of the exposed part of the substrate sheet and a hydrophilic area consisting of the exposed part of the cellulose fiber layer, the hydrophilic area extending in one direction, The hydrophilic region and the hydrophobic region are adjacent to each other in a direction orthogonal to the extending direction,
The basis weight of the cellulosic fiber layer, 0 g / ^{m 2} Ultra 10 g / ^{m 2} or less is laminated sheet.   The laminated sheet according to claim 1 or 2, wherein the hydrophobic regions are present on both sides of one of the hydrophilic regions in the direction orthogonal to the extending direction.   The laminated sheet according to any one of claims 1 to 3, wherein the plurality of hydrophilic regions and the plurality of hydrophobic regions are alternately present in a direction orthogonal to the extending direction of the plurality of hydrophilic regions.   The laminated sheet according to any one of claims 1 to 4, wherein the hydrophobic area is present at both ends of the laminated sheet in a direction orthogonal to the extending direction of the hydrophilic area on the surface having the hydrophilic area. .   An absorbent article comprising the laminated sheet according to any one of claims 1 to 5. A liquid-retaining absorbent core having a longitudinal direction corresponding to the front-rear direction of the wearer and a transverse direction orthogonal thereto, wound around the absorbent core, and the skin-facing surface and the non-skin facing of the absorbent core And a core wrap sheet covering the surface, and on the non-skin-facing surface side of the absorbent core, both side edges along the longitudinal direction of the core wrap sheet overlap to form a sheet side edge overlapping portion Yes,
The core wrap sheet is the laminated sheet, and the extending direction of the hydrophilic region in the laminated sheet coincides with the longitudinal direction,
The absorbent according to claim 6, wherein a hydrophobic region overlapping portion in which the hydrophobic region at one of both side edges of the core wrap sheet overlaps the hydrophobic region at the other is present at the sheet side edge overlapping portion. Goods. A sheet-forming step of supplying a slurry containing cellulose-based fibers to a substrate sheet, and partially forming a cellulose-based fiber layer on one side of the substrate sheet by sheet-forming;
The manufacturing method of the lamination sheet which has the division process of cutting the lamination sheet obtained through the above-mentioned paper-making process in the non-formation position of the above-mentioned cellulose fiber layer, and dividing into plurality.

Images