JP6554028B2 - Sheet-like material - Google Patents

Description

  The present invention relates to a sheet-like material used for an absorbent article.

  In general, an absorbent used for absorbent articles such as disposable diapers, sanitary napkins, incontinence pads, etc. is prepared by placing an absorbent material containing pulp fibers and a water-absorbing polymer on an outer peripheral surface of a rotating drum on an air stream. It is manufactured by suctioning and depositing in the formed recess, and then covering the piled body deposited in the recess with a water-permeable sheet material. However, the weight of the water absorbing polymer is very heavy compared to the weight of the pulp fiber, and the dispersion of the water absorbing polymer tends to be uneven. In such a non-uniform absorbent body, swelling inhibition such as gel blocking is likely to occur, and the absorption performance of the water-absorbing polymer cannot be maximized.

  As a technique different from the above technique, the present applicant has previously described an absorbent article including an absorbent body formed from a laminate of absorbent sheets, and the absorbent body has a longitudinal slit along the longitudinal direction. The technique regarding the absorbent article currently distributed and formed in the excretion part opposing part was proposed (patent document 1).

  Further, as a technique different from the above technique, Patent Document 2 discloses an absorbent article in which a hydrophilic fiber sheet is disposed between a liquid-permeable surface sheet and an absorbent body, and the liquid-permeable surface sheet. Describes an absorbent article in which the hydrophilicity of the surface on the absorber side is made higher than the hydrophilicity of the surface on the surface sheet side by applying a surfactant.

JP, 2015-42244, A JP, 2005-87659, A

  Since the absorptive article given in patent documents 1 is provided with the absorber with which the vertical slit was arranged in the state of dispersion, body fluid can be quickly absorbed into the absorptive body. However, for example, when pressure is applied to the absorber that has absorbed the body fluid by the operation of the wearer standing up, etc., there is a possibility that the absorbed body fluid may be returned to the liquid. It has been found that there is a need to further prevent such liquid reversion.

  Further, in the absorbent article described in Patent Document 2, the hydrophilicity of the hydrophilic fiber sheet between the liquid-pervious surface sheet and the absorber is higher on the surface on the absorber side than on the surface on the surface sheet side. , Body fluid can be transferred to the absorber. However, when pressure is applied to the absorber that has absorbed the body fluid, the absorbed body fluid is likely to move to the highly hydrophilic surface of the hydrophilic fiber sheet disposed on the absorber. I will return. Further, Patent Document 2 does not describe anything about providing a slit in the absorber, nor does it describe anything about providing a difference in hydrophilicity in the absorber.

  Therefore, the present invention is to provide a sheet which can eliminate the drawbacks of the prior art described above.

  The present invention is fixed to the surface of the elongated base portion having the transverse direction, the longitudinal direction longer than the transverse direction, and the thickness direction, and the non-skin opposing surface of the elongated base portion. A sheet for an absorbent article, comprising a plurality of absorbent units comprising particles of a water-absorbing polymer, wherein each of the absorbent units is arranged so that its longitudinal direction is in one direction, The elongated base portion provides a sheet-like material in which the hydrophilicity of the non-skin facing surface is higher than the hydrophilicity of the skin facing surface.

  ADVANTAGE OF THE INVENTION According to this invention, while being able to absorb a bodily fluid quickly, it is hard to generate | occur | produce swelling inhibition and the sheet-like material which can exhibit the absorption performance of a water absorbing polymer to the maximum is provided. Moreover, according to this invention, even if a pressure is applied to the absorber which absorbed the bodily fluid, the sheet-like material from which the absorbed bodily fluid is hard to return is provided.

FIG. 1 is a cross-sectional view schematically showing an embodiment of a sheet-like article for an absorbent article of the present invention, and shows a state before water-absorbing polymer particles absorb liquid. FIG. 2 is a cross-sectional view schematically showing a state in which particles of the water-absorbing polymer in the sheet-like material shown in FIG. 1 absorb liquid and swell. FIG. 3 is a perspective view of the sheet-like material shown in FIG. 1 as viewed from above. FIG. 4 is a schematic view showing an embodiment of a manufacturing apparatus of the sheet-like material shown in FIG. FIG. 5 is a schematic perspective view of a base sheet cutting portion provided in the manufacturing apparatus shown in FIG. FIG. 6 is a perspective view of still another embodiment of the sheet-like material of the present invention viewed from the upper surface side, and shows a state before the water-absorbing polymer particles absorb the liquid (corresponding to FIG. 3). .

The present invention will be described based on its preferred embodiments with reference to the drawings.
The sheet-like article of the present invention is used for an absorbent article. Absorbent articles are generally used for absorbing and holding excretory body fluids such as urine and menstrual blood. Absorbent articles include, for example, disposable diapers, sanitary napkins, incontinence pads, etc., but are not limited to these, and widely include articles used to absorb liquid discharged from the human body. It is.

  The absorbent article typically comprises a liquid-retaining absorbent, a surface sheet disposed on the skin-facing surface of the absorbent, and a backsheet disposed on the non-skin-facing surface of the absorbent. And. And this absorber has the sheet-like material of this invention, and the liquid-permeable core wrap sheet which coat | covers this sheet-like material. That is, the sheet-like material of the present invention is used for an absorbent article, for example, as an absorbent body covered with a liquid-permeable core wrap sheet. In the absorbent article, a so-called sublayer sheet may be disposed on at least one of the skin facing surface and the non-skin facing surface of the absorbent.

  As the top sheet, the back sheet, and the core wrap sheet, materials generally used in the art can be used without particular limitation. For example, as the surface sheet, liquid permeable sheets such as various nonwoven fabrics and perforated films subjected to a hydrophilic treatment can be used. As the back sheet, a liquid permeable or water repellent sheet such as a thermoplastic resin film or a laminate of the film and a nonwoven fabric can be used. The back sheet may have water vapor permeability. Further, as the core wrap sheet, a thin paper (tissue paper) manufactured by a wet sheet-forming method, a liquid-permeable nonwoven fabric, or the like can be used. Moreover, the said absorbent article may further comprise various members according to the specific use of this absorbent article. Such components are known to those skilled in the art. For example, when applying an absorbent article to a disposable diaper or a sanitary napkin, a pair or two or more pairs of leak-proof cuffs can be disposed on the left and right sides of the topsheet.

  1 and 2 are sectional views schematically showing a sheet-like material 1 (hereinafter also simply referred to as “sheet-like material 1”) which is a preferred embodiment of the sheet-like material of the present invention. There is. The sheet-like material 1 shown in FIG. 1 shows a state before the particles of the water-absorbing polymer absorb the liquid (hereinafter, also simply referred to as “the state before use”). Also, the sheet-like material 1 shown in FIG. 2 shows a state in which the water-absorbing polymer particles have absorbed the liquid and swelled (hereinafter also simply referred to as “the state after swelling”). Here, the state after swelling means the state of water-absorbing polymer particles after immersing the sheet-like material 1 for 60 minutes in physiological saline (0.9 mass% sodium chloride aqueous solution) adjusted to 25 ° C. Do. Moreover, the perspective view of the sheet-like article 1 of the state before use is shown by FIG.

  A sheet-like object 1 shown in FIG. 1 has a long direction having a horizontal direction (X direction), a vertical direction (Y direction) longer than the horizontal direction (X direction), and a thickness direction (Z direction). Unit 2 and an absorbent unit 4 comprising particles 3 of a water absorbing polymer fixed on the surface of the non-skin facing surface of the elongated substrate 2 (hereinafter, also simply referred to as "water absorbing polymer 3") A plurality of absorbent units 4 are arranged, and each absorbent unit 4 is arranged so that its longitudinal direction (Y direction) faces at least one direction. Here, the horizontal direction (X direction), the vertical direction (Y direction), and the thickness direction (Z direction) of the elongated base portion 2 are the horizontal direction (X direction) and the vertical direction (Y direction) of the absorbent unit 4. ) And the thickness direction (Z direction). In this embodiment, the sheet material 1 also matches the horizontal direction (X direction), the vertical direction (Y direction), and the thickness direction (Z direction). (See Figure 3). In addition, the longitudinal direction (Y direction) of the sheet-like object 1 corresponds with the wearer's front-back direction when the absorbent article provided with the sheet-like object 1 is worn.

  1 is formed by arranging a plurality of absorbent units 4 such that the longitudinal direction (Y direction) of the absorbent unit 4 faces the longitudinal direction (Y direction) of the sheet 1. (See Figure 3). Between the absorbent units 4 and 4 adjacent to each other in the lateral direction (X direction) of the elongated base portion 2 (absorbent unit 4), inclusions are not included from the viewpoint of ease of movement of the absorbent unit 4 It is in the state of existence. That is, the absorbent unit 4 is in a state where it is not covered by the inclusions. In FIG. 1 and FIG. 2, the upper surface of the elongated base portion 2 is the skin facing surface facing the wearer's skin, and the lower surface of the elongated base portion 2 is the non-skin facing surface facing the back sheet. .

The absorbent unit 4 of the absorber 1 is formed in a rectangular shape that is long in the vertical direction Y in a state before use. The absorbent unit 4 preferably has a length Lx in the lateral direction X of 0.5 mm or more and 10 mm or less, and more preferably 1 mm or more and 5 mm or less. The length Ly in the longitudinal direction Y of the absorbent unit 4 is preferably 20 times or more and 200 times or less, more preferably 40 times or more and 80 times or less with respect to the length Lx in the horizontal direction X. Under the condition that the magnification is satisfied, the length Ly of the absorbent unit 4 in the longitudinal direction Y is preferably 10 mm or more and 500 mm or less, more preferably 200 mm or more and 400 mm or less. Thus, the absorbent unit 4 has an elongated shape.
In this embodiment, since the absorbent polymer is fixed to the side edge portion of the elongated base portion, the magnitude relationship of the length Lx of the length X of the absorbent unit 4 in the transverse direction with respect to the width W2 of the elongated base portion. Is preferably 0 μm <(Lx−W2) <1400 μm, and more preferably 200 μm <(Lx−W2) <1000 μm.

  In the present embodiment, the sheet-like object 1 is formed in a rectangular shape that is long in the vertical direction (Y direction) in a state before use. The sheet-like material 1 has a length in the vertical direction (Y direction) of preferably 100 mm or more and 1000 mm or less, and a length in the horizontal direction (X direction) of preferably 50 mm or more and 300 mm or less. Further, in the sheet-like material 1, the water-absorbing polymer 3 is fixed only on the surface of the non-skin facing surface of the long base portion 2 in a state before use.

  The sheet-like object 1 has an absorption region AT in which a plurality of absorbent units 4 are arranged so as to face at least one direction before use. The ratio of the absorption area AT to the entire sheet 1 is 20% from the viewpoint that the liquid is easily absorbed in the area where the particles 3 of the water absorbing polymer are fixed, in plan view of the sheet 1 in the state before use. Preferably, it is 50% or more, more preferably 100% or less, still more preferably 90% or less, specifically 20% or more and 100% or less. It is preferable that it is 50% or more and 90% or less. Here, the ratio of the absorption area AT is 100%, for example, a plurality of sheet-like materials such that the longitudinal direction (Y direction) of the absorbent unit 4 faces the longitudinal direction (Y direction) of the sheet-like material 1. In the case of juxtaposing in the lateral direction (X direction) of 1, it means an embodiment in which the absorbent unit 4 is disposed in the entire region between both ends in the longitudinal direction (Y direction) of the sheet 1 or In the case where a plurality of sheet-like objects 1 are juxtaposed in the longitudinal direction (Y direction) so that the longitudinal direction (Y direction) of the absorbent unit 4 faces the transverse direction (X direction) of the sheet-like object 1, the sheet-like object 1 means that the absorptive unit 4 is arranged in the entire region between both side portions along the longitudinal direction (Y direction). When the sheet 1 is viewed in plan, the area other than the absorption area AT is a non-slit area NT described later.

  When arranging the absorbent unit 4 so that the longitudinal direction (Y direction) of the absorbent unit 4 faces the longitudinal direction (Y direction) of the sheet-like article 1, three or more absorbent units 4 are arranged per sheet-like article. Preferably, 50 or more are arranged, more preferably 1000 or less, more preferably 500 or less, more specifically, 3 or more. It is preferable to distribute 1000 or less, and more preferable to distribute 50 or more and 500 or less. Further, when the absorbent unit 4 is arranged so that the longitudinal direction (Y direction) of the absorbent unit 4 faces the lateral direction (X direction) of the sheet-like object 1, three or more absorbent units 4 are arranged per sheet-like object. Preferably more than 50, more preferably less than 3,500, more preferably less than 2,000, specifically 3 The number is preferably at least 3500, and more preferably at least 50 and no more than 2000.

  The sheet-like object 1 before use is such that the longitudinal direction (Y direction) of the absorbent unit 4 is directed to the longitudinal direction (Y direction) of the sheet-like article 1 from the viewpoint of ease of conveyance during manufacture. It is preferable that a plurality of the absorbent units 4 are arranged, and each of the absorbent units 4 is parallel to the longitudinal direction (Y direction) so that the plurality of absorbent units 4 do not cross each other. More preferably, they are arranged in the Y direction). In the sheet-like material 1 shown in FIG. 1, a plurality of absorbent units 4 each having a long base portion 2 having a uniform width are used, and the longitudinal direction (Y direction) of the absorbent unit 4 is the longitudinal direction of the sheet-like material 1. It is disposed in parallel to the longitudinal direction (Y direction) of the sheet 1 so as to face the direction (Y direction).

  The sheet-like object 1 is a non-slit region in which a plurality of elongated base portions 2 are connected in the width direction (X direction) at both end portions in the vertical direction (Y direction) or both sides along the vertical direction (Y direction) NT is preferably provided, and the sheet-like object 1 of the present embodiment includes non-slit regions NT at both ends in the vertical direction (Y direction) as shown in FIG. That is, in the sheet-like material 1 of the present embodiment, one base sheet is provided, and the non-slit regions NT are provided at both ends in the longitudinal direction (Y direction) of the base sheet, and the non-slit A plurality of elongated base portions 2 formed by the cutting process described later are provided between the regions NT. When such a non-slit region NT is provided, the sheet shape of the sheet 1 is easily maintained in a state before use, and the structure is less likely to be disturbed, and the sheet is easily transported at the time of manufacturing. It is preferable that the water absorbing polymer 3 is not disposed in the non-slit region NT. As described above, if the water-absorbing polymer 3 is not disposed in the non-slit region NT, the water-absorbing polymer 3 does not easily swell in the non-slit region NT even if the liquid is absorbed. The sheet shape of the object 1 is easily maintained, the structure is hardly disturbed, the liquid is easily absorbed in the region where the water-absorbing polymer 3 is fixed, and the sheet-like object 1 as a whole is easily balanced. In addition, when the sheet-like object 1 is provided with non-slit regions NT at both ends in the longitudinal direction (Y direction) as in the sheet-like object 1 shown in FIG. Are easily maintained, the structure is less likely to be disturbed, and the softness of the absorbent area AT is improved so that the wearer does not feel uncomfortable. Both ends in the longitudinal direction (Y direction) are fixed to the absorbent article. Is preferred.

In the sheet-like material 1 shown in FIG. 1, the ratio (W2 / W1) of the width (W2) (the length in the lateral direction (X direction)) of the long base portion 2 to the width (W1) of the sheet-like material 1 is From the viewpoint of the amount supported on the elongated base portion 2 of the water-absorbent polymer 3, swelling inhibition, flexibility, air permeability, maintenance of the sheet shape, etc., it is preferably 0.001 or more, and 0.002 or more. More preferably, it is preferably 0.200 or less, more preferably 0.040 or less, specifically preferably 0.001 or more and 0.200 or less. More preferably, it is 002 or more and 0.040 or less.
Preferably, the width (W2) of the elongated base portion 2 is preferably 0.3 mm or more, more preferably 0.6 mm or more, and 10.0 mm or less from the same viewpoint. Preferably, it is 2.0 mm or less, more preferably 1.8 mm or less, specifically, preferably 0.3 mm or more and 10.0 mm or less, and 0.6 mm or more. It is more preferable that it is 2.0 mm or less, and it is still more preferable that it is 0.6 mm or more and 1.8 mm or less.
The width (W2) of the long base portion 2 is the distance between both side edges of the long base portion 2 along the longitudinal direction Y. The width (W1) of the sheet-like object 1 is a distance between both side edges of the sheet-like object 1 along the longitudinal direction Y.

The long base portion (base material sheet) 2 constituting the absorbent unit 4 is preferably a hydrophilic sheet from the viewpoint of improving the utilization efficiency of the water-absorbing polymer 3 because the liquid easily diffuses in the absorption region AT. . With a hydrophilic sheet, the contact angle of one component fiber is less than 90 °, or, in the case of a sheet which is not a fiber material, the contact angle of its surface is defined as less than 90 °. In addition, the measuring method follows the following method.
Moreover, the elongate base | substrate part 2 which comprises the absorptive unit 4 is a sheet | seat whose hydrophilicity of a non-skin opposing surface is higher than the hydrophilicity of a skin opposing surface. As long as the long base portion 2 is a sheet in which the hydrophilicity of the non-skin facing surface is higher than the hydrophilicity of the skin facing surface, any of paper, non-woven fabric, cloth, synthetic sponge formed by foaming synthetic resin, etc. However, among these, a nonwoven fabric is preferable from the viewpoint of having a relatively high tensile strength even if it is thin, and being thin and capable of imparting flexibility. The basis weight of the nonwoven fabric is preferably 5 g / m ² or more and 100 g / m ² or less, more preferably 10 g / m ² or more and 40 g / m ² or less.

  As the elongate base | substrate part 2 whose hydrophilicity of a non-skin opposing surface is higher than the hydrophilicity of a skin opposing surface, the nonwoven fabric manufactured by processing a non-skin opposing surface with a hydrophilizing agent can be used, for example. In addition, fibers that are inherently hydrophilic, such as natural cotton or semi-natural rayon fiber, are used for the non-skin facing side layer, or a resin kneaded with a hydrophilizing agent is used on the non-skin facing side. And a non-woven fabric manufactured using a web having a multilayer structure of two or more layers using a layer having a relatively low hydrophilicity on the skin-facing surface side. In addition, a non-woven fabric produced using inherently hydrophilic fibers such as natural cotton or semi-natural rayon fibers is used on the non-skin facing side, or a resin kneaded with a hydrophilizing agent is used. After using the nonwoven fabric produced using the non-skin facing surface side, and using the nonwoven fabric produced using a relatively low hydrophilic resin on the skin facing surface side, A non-woven fabric having an integrated multilayer structure can be used. As the elongated base portion 2 of the sheet 1 shown in FIGS. 1 and 2, the layer 21 having a relatively high degree of hydrophilicity and the non-skin facing surface side, which uses a resin into which a hydrophilizing agent is kneaded, and the relative A non-woven fabric manufactured using a web having a two-layer structure formed of a layer 22 on the side facing the skin having a low degree of hydrophilicity is used. In addition, as surfactant used as a hydrophilizing agent, various well-known surfactant is mentioned as a typical thing. As the surfactant, anionic, cationic, zwitterionic and nonionic surfactants can be used.

  The level of hydrophilicity of the skin facing surface and the non-skin facing surface is preferably the level of hydrophilicity of the constituent fibers, and can be determined using the contact angle of ion-exchanged water to the constituent fibers as an index. That is, the contact angle is the angle between the water droplet on the constituent fiber and the constituent fiber surface, and it can be determined that the smaller the contact angle, the higher the degree of hydrophilicity. Further, when the difference in contact angle is within ± 3 °, it is judged that the contact angles are almost the same, and the hydrophilicity is almost equal.

(The hydrophilicity of the non-skin facing surface is higher than the hydrophilicity of the skin facing surface) The hydrophilicity of the skin facing surface of the elongated base portion 2, ie, the contact angle of ion exchange water with the constituent fibers forming the skin facing surface Is preferably 80 ° or more, more preferably 90 ° or more, and preferably 180 ° or less, preferably 120 ° or less, from the viewpoint of absorbing the liquid far from the skin. More specifically, it is preferably 80 ° or more and 180 ° or less, and more preferably 90 ° or more and 120 ° or less. The hydrophilicity of the non-skin facing surface of the elongated substrate portion 2, that is, the contact angle of the ion exchange water to the constituent fibers forming the non-skin facing surface, is 0 ° or more from the viewpoint of absorbing the liquid at a distance from the skin. Is preferably 30 ° or more, more preferably 90 ° or less, still more preferably 70 ° or less, and specifically 0 ° or more and 90 ° or less It is more preferable that the temperature is 30 ° C. or more and 70 ° or less.
Further, the difference between the contact angle of the skin-facing surface of the elongated base portion 2 and the contact angle of the non-skin-facing surface (the former-the latter) is preferably greater than 4 °, more preferably 5 ° or more. It is preferably 7 ° or more and 30 ° or less, more preferably 25 ° or less, and still more preferably 20 ° or less. Specifically, it is preferably 4 ° or more and 30 ° or less, more preferably 5 ° or more and 25 ° or less, and still more preferably 7 ° or more and 20 ° or less.

<Method of measuring the degree of hydrophilicity of the skin facing surface or the non-skin facing surface of the elongated base portion 2>
The degree of hydrophilicity of the skin-facing or non-skin-facing surface of the elongated substrate portion 2 is determined by measuring the contact angle of water to the component fibers forming the skin-facing or non-skin-facing surface of the elongated substrate portion 2. can get. The contact angle of water with the constituent fibers forming the skin-facing surface or the non-skin-facing surface of the elongated base portion 2 (non-woven fabric) is measured by the following method. As a measuring device, an automatic contact angle meter MCA-J manufactured by Kyowa Interface Science Co., Ltd. is used. Distilled water is used for contact angle measurement. The amount of liquid discharged from an ink jet type water droplet discharge part (manufactured by Cluster Technology, Inc., pulse injector CTC-25 having a discharge part pore diameter of 25 μm) is set to 20 picoliters, and a water drop is dropped directly above the constituent fibers. The state of dropping is recorded on a high-speed recording device connected to a camera installed horizontally. The recording device is preferably a personal computer incorporating a high-speed capture device from the viewpoint of image analysis or image analysis later. In this measurement, an image is recorded every 17 msec. In the recorded video, the first image in which water drops have deposited on the component fibers that form the non-skin facing or non-skin facing side of the non-woven fabric, attached software FAMAS (software version is 2.6.2, analysis method is liquid Image analysis is performed using the drop method, the analysis method is the θ / 2 method, the image processing algorithm is non-reflection, the image processing image mode is frame, the threshold level is 200, and curvature correction is not performed. The angle between the surface touching the surface and the component fiber is calculated, and this is taken as the contact angle.
In addition, the sample for measurement (constituent fiber obtained by taking it out of the non-woven fabric) is obtained by cutting the constituent fiber on the skin facing surface or non-skin facing surface of the non-woven fabric from the outermost layer with a fiber length of 1 mm, It mounts on a stand, keeps it horizontal, and measures two different contact angles for one constituent fiber. In each of the above-described portions, N = 5 contact angles are measured to one digit after the decimal point, and a value obtained by averaging ten measured values in total (rounded to the second decimal digit after the decimal point) is defined as each contact angle.

  As the water absorbent polymer 3 fixed to the surface of the non-skin facing surface of the elongated base portion 2, various kinds of materials conventionally used in the technical field of the absorbent article can be used. Acid soda, (acrylic acid-vinyl alcohol) copolymer, crosslinked polyacrylic acid soda, (starch-acrylic acid) graft polymer, (isobutylene-maleic anhydride) copolymer and saponified product thereof, potassium polyacrylate And cesium polyacrylate and the like, and one of these may be used alone or in combination of two or more. As the water-absorbing polymer 3, there are amorphous type, massive type, bowl-like type, spherical particle aggregation type, spherical type and the like from the difference in the shape, and any type can be used. The spherical type is used.

  As a method of fixing the particles 3 of the water-absorbing polymer on the surface of the elongated base portion 2, a method using an adhesive, a method of supporting the particles chemically using hydrogen bonding or the like, or the elongated base portion 2 In the case where the fabric is a non-woven fabric or a cloth, a method of raising its constituent fibers and fixing between the raised constituent fibers, etc. may be mentioned. In the sheet 1 shown in FIG. 1 and FIG. It is used. That is, the water-absorbing polymer particles 3 of the sheet-like material 1 are fixed to the surface of the non-skin facing surface of the layer 21 of the long base portion 2 via the adhesive 5. Thus, when the particles 3 of the water absorbing polymer are fixed to the surface of the elongated base portion 2 through the adhesive 5, the water absorbing polymer in the state before use of the sheet 1 or after the swelling. Particles 3 are less likely to fall off.

For example, a hot melt adhesive is preferably used as the adhesive 5. Examples of the hot melt adhesive include styrenes and olefins. Styrene-based hot melt adhesives include styrene-butadiene-styrene copolymer (SBS), styrene-isoprene-styrene copolymer (SIS), and styrene-ethylene-butylene-styrene copolymer, which is a hydrogenated product of SBS. (SEBS) and blended hot-melt adhesives obtained by blending two or more of these can be used. Among these, from the viewpoint of easily balancing the tack force and the cohesive force, a blended hot-melt adhesive of SIS and SBS or a blended hot-melt adhesive of SIS and SEBS is preferably used. The coating amount of the hot melt adhesive is preferably 0.5 g / m ² or more and 100 g / m ² or less, and more preferably 5 g / m ² or more and 50 g / m ² or less.

  With regard to the sheet 1 shown in FIG. 1, in the state before use, the elongated base portions 2 and 2 of the absorbent units 4 adjacent in the lateral direction (X direction) are the sheets of the sheet 1 before use. From the viewpoint that the shape is easily maintained, the structure is less likely to be disturbed, and the water absorbing polymer 3 can be disposed at an appropriate position, it is preferable that at least a part be adjacent, and the lengths adjacent in the lateral direction (X direction) It is further preferable that the elongated base portions 2 and 2 are entirely adjacent to each other. In addition, in the sheet-like object 1 shown in FIG. 1, the elongate base | substrate parts 2 and 2 adjacent to a horizontal direction (X direction) are adjacent over the whole. Here, “adjacent” means that adjacent long base portions 2 and 2 are adjacent to each other and continue.

  The sheet-like material 1 swells beyond the side edge 2s along the longitudinal direction (Y direction) of the elongated base portion 2 in the state after swelling as shown in FIG. It is done like that. Here, the swelling of the water-absorbing polymer particles 3 beyond the side edge portion 2s of the elongated base portion 2 means, in other words, the swollen water absorption shown in FIG. It means that the swollen water-absorbing polymer particles 3 exist across the side edge portion 2s of the elongated base portion 2 like the conductive polymer particles 3a. In the state after swelling of the sheet-like material 1, if the swollen water-absorbent polymer particles 3 are present across the side edge 2 s of the elongated base portion 2, the sheet-like material 1 In the state before use, the particles 3 of the water absorbing polymer may be present inside the side edge 2s of the elongated base portion 2 or, for example, before use (before swelling) shown in FIG. Like the water-absorbing polymer particles 3 b, the water-absorbing polymer particles 3 may be present across the side edge 2 s of the long base portion 2 from the beginning.

  Furthermore, in the sheet-like material 1, in the state after swelling as shown in FIG. 2, the position of the particles 3 of the water-absorbing polymer in the elongated substrate portion 2 is vertically shifted in the thickness direction (Z direction). And so on, it is made different from the position before absorbing the liquid. Here, in the state after swelling of the sheet-like material 1, the particles 3 of the water-absorbing polymer are different in the position of the elongated base portion 2 in the thickness direction (Z direction) from the position before absorbing the liquid. The position of the elongated base portion 2 in the state after swelling and the position of the elongated base portion 2 in the state before use (before swelling) of the particles 3 of the water-absorbing polymer are formed differently Means

  With respect to the sheet-like material 1 of the present embodiment described above, the sheet-like material 1 is covered with a liquid-permeable core wrap sheet to form an absorber, and the liquid-permeable surface sheet is formed on the skin-facing surface side of the absorber. According to the absorbent article which is disposed and the liquid impervious back sheet is disposed on the non-skin opposing surface side of the absorbent, the plurality of absorbent units 4 provided with the water absorbent polymer 3 face at least one direction. Because they are arranged in a similar manner, it is difficult for the adjacent absorbent units 4 and 4 to buffer each other, so that they can quickly absorb the body fluid, hardly generate swelling inhibition, and maximize the absorption performance of the water absorbing polymer. it can. Here, since the hydrophilicity of the non-skin facing surface of the elongated base portion 2 constituting the absorbent unit 4 is higher than the hydrophilicity of the skin facing surface, the body fluid is on the non-skin facing surface side It can be drawn to the back sheet side, it can diffuse the body fluid on the non-skin facing side, and the absorber can be widely used. As described above, when the body fluid is held on the non-skin facing surface side of the absorbent body, the load on the skin can be reduced because the body fluid is separated from the wearer's skin. In particular, in the sheet-like material 1, since the water-absorbing polymer particles 3 are fixed only to the surface of the long base portion 2 on the non-skin facing surface, the load on the skin can be further reduced.

  In addition, even when pressure is applied to the absorbent body that has absorbed the body fluid while wearing the absorbent article, the elongated base portion 2 constituting the absorbent unit 4 has the hydrophilicity of the non-skin opposing surface facing the skin Since it is formed higher than the hydrophilicity of the surface, the absorbed body fluid does not easily move to the skin facing surface side, and the absorbed body fluid does not easily return. In particular, in the sheet 1, since the water absorbing polymer particles 3 are fixed only to the surface of the non-skin facing surface of the elongated base portion 2, the absorbed body fluid is more difficult to transfer to the skin facing surface. , It is difficult for the absorbed body fluid to return again.

  Further, as shown in FIG. 2, in the state after swelling, the sheet 3 of the water-absorbing polymer swells beyond the side edge 2 s of the elongated base portion 2 as shown in FIG. The position of the water-absorbing polymer particles 3 in the elongated substrate portion 2 is different from the position before absorbing the liquid in the thickness direction (Z direction) (see the polymer polymer particles 3a). Therefore, when the sheet-like material 1 is used in an absorbent article, as shown in FIG. 2, when the particles 3 of the water-absorbing polymer absorb and swell body fluid, the adjacent absorbent units 4, 4, even if the water-absorbing polymer particles 3, 3 swollen beyond the side edge 2 s of the long base portion 2 come into contact with each other, the adjacent absorbent units 4, 4 are in the thickness direction (Z direction). ), The collision between the swollen water-absorbing polymer particles 3 and 3 is alleviated, the pressure applied to the swollen water-absorbing polymer particles 3 can be reduced, and the absorption of the body fluid of the water-absorbing polymer particles 3 can be reduced. It is hard to inhibit. Therefore, in the sheet-like material 1 of the present embodiment, when the water-absorbing polymer particles 3 are swollen by absorbing the body fluid, the water-absorbing polymer particles 3 are unlikely to inhibit swelling, and the water-absorbing polymer particles 3 Absorption performance can be maximized, so it is easy to improve the absorption performance. In particular, in the sheet-like material 1 according to the present embodiment, since the inclusions are not present between the adjacent absorbent units 4 and 4, the absorbent unit 4 is easily moved, and the above effect is further easily achieved. It has become.

  Further, in the sheet-like material 1 in the state after swelling as shown in FIG. 2, the positions of the elongated base portions 2 and 2 constituting the adjacent absorbent units 4 are in the thickness direction (Z direction) It is made different. Therefore, the adjacent absorbent units 4 and 4 are easy to move freely in the thickness direction (Z direction), the collision between the swollen water-absorbing polymer particles 3 and 3 is easy to relax, and the swollen water-absorbing polymer particles The pressure applied to 3 can be reduced, and it is difficult to inhibit the absorption of the body fluid of the water-absorbing polymer particles 3.

  In the sheet-like material 1, the water-absorbing polymer particles 3 in a swollen state are swollen beyond the side edge 2 s of the long base portion 2, so that the adjacent absorbent units 4, 4 are in the thickness direction (Z 1 from the viewpoint of making it difficult to cause swelling inhibition of the particles 3 of the water-absorbing polymer, and the particles 3 of the water-absorbing polymer in the elongated substrate portion 2 in the state before use as shown in FIG. It is preferable that it is arranged in the vicinity of the side edge 2s along the vertical direction (Y direction), and that the water-absorbing polymer particles 3 protrude beyond the side edge 2s of the elongated base 2. More preferable (see the water-absorbing polymer particles 3b shown in FIG. 1).

  Further, in the sheet-like material 1, the water-absorbing polymer particles 3 in a swollen state are swollen beyond the side edge 2 s of the long base portion 2, so that the adjacent absorbent units 4, 4 are in the thickness direction. The distance between the side edges 2s and 2s along the longitudinal direction (Y direction) of the elongated base portion 2 from the viewpoint of freely moving in the (Z direction) and making it more difficult to inhibit swelling of the water-absorbing polymer particles 3 However, it is preferably larger than the average particle diameter of the water-absorbing polymer particles 3 before use (before swelling) and smaller than the average particle diameter of the water-absorbing polymer particles 3 after swelling. The distance between the side edges 2s, 2s of the long base portion 2 has the same meaning as the width (W2) of the long base portion 2 described above. The average particle diameter d1 of the water-absorbent polymer particles 3 in the state before use (before swelling) is preferably 20 μm or more, more preferably 200 μm or more, and preferably 700 μm or less, 500 μm More preferably, it is preferably 20 μm or more and 700 μm or less, and more preferably 200 μm or more and 500 μm or less. On the other hand, the average particle diameter d2 of the water-absorbent polymer particles 3 in a swollen state is preferably 200 μm or more, more preferably 800 μm or more, and preferably 3000 μm or less, and 2000 μm or less. It is more preferable that the thickness be 200 μm or more and 3000 μm or less, and more preferably 800 μm or more and 2000 μm or less. The average particle size of the water-absorbing polymer 3 can be determined by the following measurement method.

<Method of measuring average particle diameter d1 of particles of water-absorbing polymer in a state before use>
The average particle diameter d1 in the state before use was determined by observing the diameter or major axis of the water-absorbing polymer particles with an optical microscope using the water-absorbing polymer particles before use. Here, the diameter refers to the case where the particles of the water absorbing polymer are spherical. Further, the long axis refers to a case where particles of the water-absorbing polymer have a diamond-like shape, a rectangular shape, a tufted shape, a football shape or the like. The diameter or major axis of a total of 50 water-absorbing polymer particles is measured, and the number average particle diameter is defined as the average particle diameter d1 of the water-absorbing polymer particles in a state before use.

<Measuring method of average particle diameter d2 of water-absorbing polymer particles after swelling>
The average particle diameter d2 in the swollen state is such that the sheet 1 is immersed in a physiological saline (0.9 mass% sodium chloride aqueous solution) adjusted to 25 ° C., and the sheet 1 is 1 hour after the start of the immersion. Was taken out from the physiological saline, suspended in a vertical state for 30 minutes and drained, and then the diameter or the major axis of the water-absorbing polymer particles on the surface of the elongated substrate portion 2 was measured by optical microscope observation. The diameter here refers to the case where the water-absorbing polymer particles are spherical. The long axis refers to a case in which the water-absorbing polymer particles have an irregular shape such as a rhombus, rectangle, tuft, or football. The diameter or major axis of a total of 50 water-absorbing polymer particles can be measured, and the number average particle diameter can be measured as the average particle diameter of the water-absorbing polymer particles in the swollen state.

  Next, a preferred embodiment of the method for producing a sheet-like material according to the present invention will be described with reference to FIG. The manufacturing apparatus 100 preferably used for the manufacturing method of this embodiment is shown by FIG. The manufacturing apparatus 100 of the present embodiment includes a base sheet cutting unit 110, an adhesive application unit 120, and a water absorbing polymer spraying unit 130 in this order from the upstream side to the downstream side of the manufacturing process. In addition, in the manufacturing apparatus 100 shown in FIG. 4, although the apparatus which the adhesive agent application part 120 and the water absorbing polymer dispersion part 130 integrated is used, the adhesive application part 120 and the water absorbing polymer dispersion part 130 are integrated. You do not have to. The integrated device has a configuration in which the adhesive application unit 120 is disposed on the upstream side of the device, and the water absorbing polymer scattering unit 130 is disposed on the downstream side of the integrated device.

  The base material sheet cutting part 110 is a part that cuts the belt-like base material sheet 20 that is a raw material of the long base part 2 to form a plurality of long base parts 2. Various known cutting devices can be used for cutting the base sheet 20 without particular limitations, but in the manufacturing device 100, as shown in FIG. 5, a plurality of cutter blades 111a, 111a, 111a,. A cutting device 113 including a rotary die 111b in which a... Is disposed and a receiving roll 112 having a flat peripheral surface disposed opposite to the rotary die 111b is used. The cutter blades 111a of the cutting device 113 are arranged in the rotation direction of the rotary die 111b, and the plurality of cutter blades 111a, 111a, 111a,. Are arranged in the direction (X1 direction) orthogonal to the The distance between the cutter blades 111a and 111a adjacent to each other in the orthogonal direction (X1 direction) corresponds to the width (length in the horizontal direction (X direction)) of each of the elongated base portions 2 to be formed. Here, the conveyance direction (Y1 direction) of the base sheet 20 corresponds to the longitudinal direction (Y direction) of the sheet-like material 1 to be manufactured, and the orthogonal direction (X1 direction) is the sheet shape to be manufactured. This corresponds to the horizontal direction (X direction) of the object 1. The base sheet 20 may be cut using a shear-cut type cutting device that rubs and cuts the side surfaces of the upper blade and the lower blade, and a plurality of score cut knives are orthogonally crossed (X1 direction). It may be a juxtaposed device, or a laser device that emits a laser beam to cause melting may be used.

  When the sheet-like object 1 includes the non-slit regions NT at both ends in the longitudinal direction (Y direction) like the sheet-like object 1 shown in FIG. 3, for example, as shown in FIG. The concave portion 114 may be formed on the circumferential surface of the cutter blade 111a. The length of the arc of the concave portion 114 in the outer periphery of the rotating cutter blade 111a is the sum of the lengths in the longitudinal direction (Y direction) of the non-slit regions NT arranged at both ends of the sheet 1 shown in FIG. Make them correspond to equal lengths. If a plurality of cutter blades 111a, 111a, 111a... Having such a recess 114 are prepared and a rotary die 111b is used in which the positions of the recesses 114, 114 of the cutter blades 111a adjacent to each other in the X1 direction are aligned. Good. The length of the arc of the portion of the outer periphery of the rotating cutter blade 111a excluding the concave portion 114 corresponds to the length in the longitudinal direction (Y direction) of the elongated base portion 2 of the sheet 1 shown in FIG. doing. When the sheet 1 has the non-slit regions NT on both sides along the longitudinal direction (Y direction), the cutter blade 111a should not be disposed at the position corresponding to the non-slit regions NT. Good.

  The adhesive application part 120 located on the downstream side of the base sheet cut part 110 is a part that applies the adhesive 5 to the surface of one surface (upper surface) of the elongated base part 2, and in the manufacturing apparatus 100 As shown in FIG. 4, an application head 121 is provided. For the coating head 121, various known coating devices can be used without particular limitation. The coating head 121 is formed to have a length corresponding to the width (the length in the horizontal direction (X direction)) of the absorption region AT of the sheet-like object 1 in the X1 direction. The coating heads 121 formed in this manner are arranged on one surface (upper surface) of the elongated base portion 2 at intervals.

  The water absorbing polymer scattering unit 130 located on the downstream side of the adhesive application unit 120 spreads the particles 3 of the water absorbing polymer on the surface of one surface (upper surface) of the elongated base 2 to obtain the absorbing unit 4. This is a part to be formed, and as shown in FIG. 4, the manufacturing apparatus 100 is provided with a water absorbing polymer introducing part 131. Various known introduction devices can be used for the water-absorbent polymer introduction portion 131 without particular limitation. The water-absorbing polymer introduction part 131 is formed to have a length corresponding to the width (the length in the horizontal direction (X direction)) of the absorption region AT of the sheet-like material 1 in the X1 direction. The water-absorbing polymer introduction part 131 formed in this way is disposed on one surface (upper surface) of the long base part 2 with a gap.

  Further, in the manufacturing apparatus 100 shown in FIG. 4, the adhesive application unit 120 and the water absorbing polymer scattering unit 130 are at a position opposed to the integrated device, and the plurality of elongated base members 2 conveyed. A vacuum conveyor 141 is disposed on the lower surface side. The vacuum conveyor 141 includes an endless breathable belt 144 laid across a drive roll 142 and a plurality of driven rolls 143, and a vacuum box disposed at a position facing the integrated device with the breathable belt 144 interposed therebetween. And 145 are provided. On the vacuum conveyor 141, a plurality of long base parts 2 formed by cutting the base material sheet 20 at the base material sheet cutting part 110 are introduced.

  Further, in the manufacturing apparatus 100 shown in FIG. 4, a driving roll 151 for feeding out the base sheet 20 from the raw sheet roll of the belt-like base sheet 20 and the precursor 1 b of the sheet 1 manufactured at the most downstream side. And a driving roll 152 for conveying the

Next, an embodiment of a method for continuously manufacturing the sheet-like material 1 using the manufacturing apparatus 100 of the above-described embodiment, that is, a method for manufacturing the sheet-like material of the present invention will be described.
In the method of manufacturing the sheet-like article 1 of the present embodiment, in the cutting step of cutting the strip-like base sheet 20 to form a plurality of elongated base portions 2, and in the step after the cutting step, It comprises a particle scattering step of a water-absorbing polymer for scattering particles 3. Moreover, in this embodiment, the adhesive application process which applies the adhesive agent 5 is provided in the front process rather than the particle | grain dispersion process of a water absorbing polymer. That is, the method for producing the sheet-like product 1 of the present embodiment includes the adhesive application step after the cutting step and the particle scattering step of the water absorbing polymer after the adhesive application step.

  Prior to the execution of the cutting process, first, the inside of the vacuum box 145 is operated to a negative pressure by operating an exhaust device connected thereto.

  As the base sheet 20, a web having a two-layer structure formed of a layer 21 having a relatively high degree of hydrophilicity on the non-skin facing surface side and a layer 22 having a relatively low hydrophilicity side on the skin facing surface is used A strip-shaped non-woven fabric manufactured in this way is used. And the base material sheet 20 is arrange | positioned so that the layer 21 with a relatively high hydrophilicity may face the one surface (upper surface) side.

  Next, the drive roll 151 and the drive roll 152 are driven to rotate the cutting device 113 and the air-permeable belt 144 to operate the vacuum conveyor 141. Then, the base sheet 20 is unrolled from the raw material roll of the belt-like base sheet 20 by the driving roll 151, and is supplied between the plurality of cutter blades 111 a and the receiving roll 112 in the cutting device 113 of the base sheet cutting portion 110. The strip-shaped base sheet 20 is cut to form a plurality of elongated base portions 2 (cutting step). In the present embodiment, as shown in FIG. 5, each of the plurality of cutter blades 111a arranged in the rotational direction of the rotary die 111b is orthogonal to the conveyance direction (Y1 direction) of the strip-like base sheet 20 ( Since the belt-like base material sheet 20 is cut along the conveyance direction (Y1 direction) of the base material sheet 20 and is cut at a plurality of locations in the orthogonal direction (X1 direction), since it is arranged to coincide with the X1 direction). Thus, a plurality of long base portions 2 are formed. Further, the portion cut by the cutter blade 111 a becomes the side edge 2 s of the elongated base portion 2.

  Further, in the present embodiment, since the plurality of cutter blades 111a each have the concave portion 114, the strip-like base sheet 20 to be conveyed, the longitudinal direction of the elongated base portion 2 (Y direction) The non-cut portion NTb corresponding to twice the length in the longitudinal direction (Y direction) of the non-slit region NT is intermittently formed. The plurality of elongated base portions 2 formed in the cutting step are formed in parallel to the transport direction (Y1 direction), and are juxtaposed in the orthogonal direction (X1 direction).

  Next, the adhesive 5 is applied to the surface of one surface of the elongated base portion 2 formed in the cutting step (adhesive application step). In this embodiment, while the plurality of long base portions 2 formed in the cutting process are transported by the vacuum conveyor 141 and positioned on the vacuum box 145, the coating head 121 of the adhesive coating unit 120 is used. Intermittently on the layer 21 with high hydrophilicity, which is one surface of a plurality of elongated base portions 2 formed in parallel in the orthogonal direction (X1 direction), excluding the non-cut portion NTb, Apply adhesive 5.

  Next, the particles 3 of the water-absorbing polymer are dispersed onto the adhesive 5 applied to the surface of one side of the plurality of elongated substrates 2 formed in the adhesive application step (the water-absorbing polymer Particle scattering process). In this embodiment, the vacuum box 145 is transported by the vacuum conveyor 141 while the long base portion 2 formed by the adhesive application step and having the adhesive 5 applied to the surface of the highly hydrophilic layer 21 is conveyed. While positioned above, the surface of the highly hydrophilic layer 21 of the plurality of elongated base portions 2 juxtaposed in the orthogonal direction (direction X1) by the water absorbing polymer introduction portion 131 of the water absorbing polymer scattering portion 130 The particles 3 of the water-absorbing polymer are dispersed onto the adhesive 5 applied to the above, except for the non-cut portion NTb. By dispersing the water absorbing polymer particles 3 in this manner, a plurality of absorbent units 4 in which the water absorbing polymer particles 3 are fixed to the surface of the elongated base portion 2 via the adhesive 5 are formed. The plurality of absorbent units 4 formed in this manner are arranged such that the longitudinal direction (Y direction) of each is directed to the transport direction (Y1 direction), and the precursor 1 b of the sheet 1 is formed. You will come to

  Next, the precursor 1b of the sheet 1 is conveyed downstream by the driving roll 152, and the length of the non-cut portion NTb in the conveyance direction (Y1 direction) is measured using a known cutting device (not shown). It cut | disconnects for every position of a minute, and the sheet-like article 1 which has the non-slit area | region NT in the both ends of a vertical direction (Y direction) is manufactured continuously. As described above, according to the manufacturing apparatus 100 of the present embodiment and the manufacturing method of the present embodiment using the same, the sheet-like material 1 can be stably and efficiently manufactured. The sheet-like material 1 manufactured in this way is used so that the surface side of the highly hydrophilic layer 21 to which the adhesive 5 is applied faces the non-skin facing surface side.

  Moreover, according to the manufacturing method of this embodiment, after forming the elongate base part 2 of uniform width using a plurality of cutter blades 111a, 111a, 111a,. Since the adhesive 5 is applied to the surface of the highly hydrophilic layer 21 which is one surface, in the sheet-like material 1 produced, the elongated units of the absorbent units adjacent in the lateral direction (X direction) are produced. It is easy for the base parts 2 and 2 to be adjacent to each other throughout. Such a sheet-like material 1 can be manufactured stably and efficiently.

The present invention is not limited to the above embodiment, and can be modified as appropriate.
In the sheet-like material 1 shown in FIG. 1 described above, the water-absorbing polymer particles 3 are fixed only on the surface of the highly hydrophilic layer 21 that is one surface of each long base portion 2. From the viewpoint of improving the absorption performance of the sheet-like material 1, not only the surface of the highly hydrophilic layer 21 which is one surface of each elongated substrate portion 2 but also the low hydrophilicity layer 22 which is the other surface. It may also be fixed to the surface of. In order to fix the water-absorbing polymer particles 3 on both surfaces (upper and lower surfaces) of each elongate base portion 2, for example, one of each elongate base portion 2 is used by using a manufacturing apparatus 100 shown in FIG. After fixing the water-absorbing polymer particles 3 on the surface of the surface, the water-absorbing polymer particles 3 are reversed through a reversing roll, and then another water-absorbing polymer spraying unit 130 is used to It can manufacture by scattering and fixing the particle | grains 3 of a water absorbing polymer on the surface.

When the particles 3 of the water-absorbing polymer are fixed to the surfaces of both surfaces (upper and lower surfaces) of each elongated base portion 2, the layer 21 with high hydrophilicity of the elongated base portion 2 from the viewpoint of achieving the above effect. It is preferable that the basis weight of the water-absorbing polymer 3 fixed on the surface of the above is larger than the basis weight of the water-absorbing polymer 3 fixed on the surface of the low hydrophilicity layer 22 of the elongated base portion 2 . The basis weight of the water-absorbent polymer 3 to be fixed to the surface of the highly hydrophilic layer 21 which is one surface of the elongated base portion 2 is preferably 10 g / m ² or more and 250 g / m ² or less, 30 g / m ² and still more preferably m is ² or more 150 g / ^{m 2} or less. The basis weight of the water-absorbent polymer 3 to be fixed to the surface of the low hydrophilicity layer 22 which is the other surface of the elongated base portion 2 is preferably 30 g / m ² or more and 400 g / m ² or less, 50 g / m ² and still more preferably m is ² or more 300 g / ^{m 2} or less.

The basis weight of the water-absorbing polymer 3 fixed to the skin facing surface side in the long base portion 2 and the basis weight of the water-absorbing polymer 3 fixed to the non-skin facing surface side in the long base portion 2 are as follows. Measure by the method.
<The basis weight of the water-absorbing polymer 3 fixed to the skin facing surface side in the long base portion 2 and the basis weight of the water-absorbing polymer 3 fixed to the non-skin facing surface side in the long base portion 2 Measuring method>
In order to prevent the water absorbing polymer on the non-skin facing surface side of the elongated substrate portion 2 from falling off, the water absorbing polymer fixed on the skin facing surface side is fixed again with an adhesive or the like from the upper surface of the water absorbing polymer. Then, the adhesive is adhered to the water-absorbing polymer by peeling off from the long base portion 2 using a solvent or the like. After drying the water-absorbing polymer, the weight of the water-absorbing polymer fixed on the skin-facing surface side is measured, and the area of the elongated base portion 2 where the water-absorbing polymer is fixed is separated from the water-absorbing polymer. The weight of the water absorbing polymer fixed per unit area is calculated from the weight of the polymer, and is taken as the basis weight of the water absorbing polymer on the skin facing surface side. Five measurements are taken and the average value is calculated.
The basis weight of the water absorbing polymer on the non-skin facing surface side is similarly fixed after the water absorbing polymer on the skin facing surface side is fixed, and then the water absorbing polymer on the non-skin facing surface side is peeled off and washed.

  Moreover, when fixing the particles 3 of the water-absorbing polymer on the surfaces of both sides (upper and lower surfaces) of each elongated base portion 2, a large amount of liquid is held on the non-skin opposing surface (lower surface) far from the wearer's skin From the viewpoint of improving the touch without leaving a liquid on the skin-facing surface (upper surface), the water-absorbing polymer 3 fixed to the surface of the layer 22 having a low hydrophilicity of the long base portion 2 is Compared to the water-absorbing polymer particles 3 fixed to the surface of the layer 21 having a high hydrophilicity of the substrate 2, it is preferable that the liquid passing performance is high under pressure and the centrifugal retention amount is low. From the above point of view, regarding the water-absorbent polymer 3 fixed to the surface of the low hydrophilicity layer 22 of the elongated base portion 2, the liquid flow rate under pressure at 2.0 kPa is preferably 20 ml / min or more More preferably 40 ml / min or more, and preferably 1000 ml / min or less, more preferably 800 ml / min or less, and specifically 20 ml / min or more and 1000 ml / min or less It is preferably 40 ml / min or more and 800 ml / min or less. Further, regarding the water-absorbent polymer 3 fixed to the surface of the highly hydrophilic layer 21 of the elongated base portion 2, the liquid flow rate under pressure at 2.0 kPa is preferably 0 ml / min or more, 10 ml / Min or more is more preferable, and 400 ml / min or less is preferable, and 200 ml / min or less is more preferable, and specifically, 0 ml / min or more and 400 ml / min or less It is preferably 10 ml / min or more and 200 ml / min or less. The liquid passing speed under pressure is determined by the following measuring method.

<Measurement method of liquid flow rate under pressure>
The liquid passing rate under pressure is measured using a measuring method and a measuring apparatus described in JP-A-2003-235889. That is, in a 100 mL glass beaker, a sufficient amount of physiological saline (0.9% by mass sodium chloride aqueous solution) to swell the measurement sample water-absorbing polymer 0.32 ± 0.005 g, for example, saturation of the water-absorbing polymer. Soak in saline at least 5 times the absorbed volume and leave for 30 minutes. Separately, at the lower end of an opening of a vertically standing cylinder (inner diameter 25.4 mm), a wire mesh (mesh opening 150 μm, biocolumn sintered stainless steel filter 30SUS sold by Sansho Co., Ltd.) and a capillary (with an inner diameter of 2 mm) ( A filtration cylindrical tube provided with an inner diameter of 4 mm and a length of 8 cm) is prepared, and all the contents of the beaker including the swollen measurement sample are charged into the cylindrical tube with the cock closed. Then, insert a cylindrical rod with a diameter of 2 mm and a diameter of 2 mm at the tip of a 150 μm mesh and a diameter of 25 mm so that the mesh and the measurement sample are in contact with each other. Put a weight so that the load of. After standing for 1 minute in this state, the cock is opened to flow the liquid, and the time until the liquid level in the filtration cylindrical tube reaches the 40 mL scale line from the 60 mL scale line (that is, 20 mL of liquid passes) (T1). (Seconds) is measured. Using the measured time T1 (seconds), the liquid flow rate under pressure at 2.0 kPa is calculated from the following equation. In the equation, T0 (seconds) is a value obtained by measuring the time required for 20 ml of physiological saline to pass through the wire mesh without putting the measurement sample in the filtration cylindrical tube.
Flow rate under pressure (ml / min) = 20 × 60 / (T1-T0)
The measurement is performed 5 times (n = 5), the values at each of the upper and lower points are deleted, and the average value of the remaining three points is taken as the measured value. The measurement is performed at 23 ± 2 ° C. and 50 ± 5% humidity, and the sample is stored in the same environment for 24 hours or more before measurement. A more detailed measurement method of the liquid flow rate under pressure is described in paragraph [0008] and paragraph [0009] of JP-A 2003-235889, and the measurement apparatus is shown in FIGS. 1 and 2 of the same publication. Have been described.

  From the above viewpoint, regarding the water absorbent polymer 3 fixed to the surface of the low hydrophilicity layer 22 of the elongated base portion 2, the centrifugal retention amount (water absorption amount) is preferably 20 g / g or more, 25 g / G or more, more preferably 50 g / g or less, even more preferably 45 g / g or less, and specifically 20 g / g or more and 50 g / g or less. Preferably, it is 25 to 45 g / g. Further, regarding the water-absorbent polymer 3 fixed to the surface of the highly hydrophilic layer 21 of the elongated base portion 2, the centrifugal retention amount (water absorption amount) is preferably 25 g / g or more, and 30 g / g More preferably, it is 65 g / g or less, more preferably 55 g / g or less, and specifically 25 g / g or more and 65 g / g or less. More preferably, it is 30 g / g or more and 55 g / g or less. The centrifugal retention amount (water absorption amount) is determined by the following measurement method.

<Measuring method of centrifugal retention (water absorption)>
The measurement of the amount of centrifugal retention (the amount of water absorption) is performed according to JIS K 7223 (1996). Nylon woven fabric (sold by Sanriki Seisakusho, product name: nylon net, standard: 250 mesh) is cut into a rectangle with a width of 10 cm and a length of 40 cm, folded in half at the center in the longitudinal direction, and heat sealed at both ends to a width of 10 cm (Inside dimension 9 cm), make a 20 cm long nylon bag. Next, 1.00 g of the water-absorbing polymer as a measurement sample is precisely weighed and placed uniformly at the bottom of the produced nylon bag. Next, the nylon bag containing the sample is immersed in physiological saline (0.9 mass% sodium chloride aqueous solution) adjusted to 25 ° C. Then, after 1 hour from the start of immersion, the nylon bag is taken out from the physiological saline, suspended in a vertical state for 1 hour and drained, and then dehydrated using a centrifugal dehydrator (Kokusan Co., Ltd., model H-130C special model). The dehydration conditions are 143 G (800 rpm) for 10 minutes. After dehydration, the mass of the sample is measured, and the target centrifugal retention amount (water absorption amount) is calculated according to the following formula.
Centrifugal retention (g / g) = (a '-b-c) / c
Where a 'is the total mass (g) of the sample and nylon bag after centrifugal dewatering, b is the mass (g) of the nylon bag before water absorption (during), c is the mass of the sample before water absorption (during) (G) is represented.
The measurement is performed 5 times (n = 5), the values at each of the upper and lower points are deleted, and the average value of the remaining three points is taken as the measured value. The measurement is performed at 23 ± 2 ° C. and 50 ± 5% humidity, and the sample is stored in the same environment for 24 hours or more before measurement.

  Further, although the sheet-like material 1 shown in FIG. 1 described above is formed by using a plurality of absorbent units 4 each having the elongated base portion 2 having a uniform width, the width of the elongated base portion 2 is It may be uneven. Preferably, when the sheet-like material 1 is viewed in a plan view, the particles 3 of the water absorbing polymer are unevenly distributed and fixed, and a long basis in a portion having a relatively large basis weight of the fixed water absorbing polymer 3 The distance between the side edges 2s, 2s along the longitudinal direction (Y direction) of the base 2 may be relatively short. That is, comparing the portion with a large basis weight of the fixed water-absorbing polymer 3 with a portion with a small basis weight, the portion between the side edges 2s, 2s of the long base portion 2 in the portion with a large basis weight of the fixed water-absorbing polymer 3 The distance “d” may be formed shorter than the distance between the side edges 2s and 2s of the long base portion 2 in the portion where the fixed weight of the water absorbent polymer 3 is low. With the sheet-like product 1 having the above configuration, adjacent absorbent units 4 can easily move freely in the thickness direction (Z direction) in the portion where the fixed basis weight of the water-absorbent polymer 3 is large, Since the sheet-like material 1 is hard to become hard and the absorption performance of the water-absorbing polymer particles 3 can be maximized, the absorption performance of the sheet-like material 1 is easily improved.

  Moreover, although the sheet-like object 1 shown in FIG. 3 mentioned above is arranged so that the longitudinal direction of each of the plurality of absorbent units 4 faces the longitudinal direction (Y direction) of the sheet-like object 1, For example, as shown in FIG. 6, the plurality of absorbent units 4 may be arranged so that the longitudinal direction of each of the absorbent units 4 faces the lateral direction (X direction) of the sheet 1. In addition, the sheet-like object 1 shown in FIG. 6 is provided with the non-slit area | region NT in the both sides along a vertical direction (Y direction). When manufacturing the sheet-like article 1 shown in FIG. 6, the rotary die in which cutter blades arranged in parallel in the axial direction of the roll are intermittently arranged in the circumferential direction and a receiving roll are used to produce the rotary die. It can form by supplying the base material sheet 20 between these and the said receiving roll.

  Moreover, the sheet-like object 1 formed so that the vertical direction of each absorptive unit 4 may face multiple directions may be sufficient. As the sheet-like objects 1 arranged and formed so as to face the plurality of directions, for example, the longitudinal direction of each of the plurality of absorbent units 4 is arranged so as to face the longitudinal direction (Y direction) of the sheet-like objects 1 Regions formed on both sides along the longitudinal direction (Y direction) of the sheet-like material 1, and the longitudinal direction of each of the plurality of absorbent units 4 is the lateral direction (X direction) of the sheet-like material 1. ) And the like formed in a central portion sandwiched between the both side portions. The sheet-like objects 1 formed by arranging them in such a plurality of directions are, for example, the conveyance direction (Y1 direction) of the base sheet 20 conveyed using the plurality of cutter blades 111a and the receiving roll 112. The central part in the direction (X1 direction) of the base material sheet 20 to be transported by using a rotary die and receiving rolls which are cut at a plurality of positions along the side) and then intermittently arranged in the circumferential direction Can be formed by cutting at a plurality of points.

  Further, in the sheet-like material 1 shown in FIG. 1 described above, each absorbent unit 4 and each elongated base portion 2 extend linearly in parallel in the longitudinal direction (Y direction). It suffices to extend in the direction (Y direction). For example, each absorptive unit 4 and each long base part 2 may extend by repeating an S shape in the vertical direction (Y direction), or may extend in a jagged shape in the vertical direction (Y direction). Good.

  Further, in the method of manufacturing the sheet-like product 1 of the present embodiment described above, the adhesive application step is provided after the cutting step, and the water absorbing polymer scattering step is provided after the adhesive application step. When raising the layer 21 having a high degree of hydrophilicity, which is one surface of the substrate sheet 20, a raising process may be provided instead of the adhesive application process. Such a raising process may be provided before the cutting process. Examples of the method of performing the raising process include the method described in JP2012-092476A, the method described in JP2013-028891A, and the like.

  The following sheet-like material is further disclosed regarding the embodiment described above.

<1>
An elongated substrate portion having a transverse direction, a longitudinal direction longer than the transverse direction, and a thickness direction, and a water absorbing polymer fixed on the surface of the non-skin facing surface of the elongated substrate portion A plurality of absorptive units provided with particles, each absorbent unit being a sheet-like article for an absorbent article in which the longitudinal direction is aligned in one direction, the long shape The base portion is a sheet-like material in which the hydrophilicity of the non-skin facing surface is higher than the hydrophilicity of the skin facing surface.

<2>
In the swollen state in which the particles of the water-absorbing polymer absorb the liquid, the particles of the water-absorbing polymer swell beyond the side edge along the longitudinal direction of the long base portion, and the long The sheet-like material according to <1>, wherein the position of the water-absorbing polymer particles in the substrate-like base portion is different from the position before absorbing the liquid in the thickness direction.
<3>
The <1> or <1>, in which the particles of the water-absorbing polymer protrude beyond the side edge of the elongated base portion in a state before use of the particles of the water-absorbing polymer before absorbing the liquid. 2>.
<4>
Any one of the above items <1> to <3>, wherein the adjacent elongated base portions are at least partially adjacent to each other in a state before use before the water-absorbing polymer particles absorb the liquid. The sheet-like material described in 1.
<5>
The sheet-like material includes non-slit regions in which a plurality of the elongated base portions are connected in the lateral direction at both end portions in the longitudinal direction, and the non-slit regions include particles of the water-absorbing polymer Is not fixed, and the sheet-like material according to any one of <1> to <4>, wherein both end portions in the longitudinal direction are fixed to the absorbent article. .
<6>
In the elongated base portion, a distance between both side edges along the longitudinal direction is larger than an average particle diameter in a state before the water-absorbing polymer particles absorb the liquid, and the water-absorbing polymer particles are The sheet-like material in any one of said <1>-<5> smaller than the average particle diameter of the state which absorbed the liquid and was swollen.
<7>
When the sheet-like material is viewed in plan, the water-absorbing polymer particles are unevenly distributed and fixed, and the long base is in a portion where the basis weight of the fixed water-absorbing polymer particles is relatively large. The sheet-like material according to any one of <1> to <6>, wherein the distance between both side edges along the longitudinal direction of the part is relatively short.
<8>
<1> to <7>, wherein the water-absorbing polymer particles are fixed only to the surface of the non-skin-facing surface of the elongated base portion before the water-absorbing polymer particles absorb the liquid. A sheet-like material according to any one of the above.
<9>
The said elongate base | substrate part is a sheet-like object in any one of said <1>-<8> which is a nonwoven fabric.
<10>
The sheet-like material is formed by arranging a plurality of the absorptive units so that the longitudinal direction of the absorbent unit faces the longitudinal direction of the sheet-like material, and in the lateral direction of the elongated base portion The sheet-like material according to any one of <1> to <9>, wherein inclusions are not present between adjacent absorbent units.

<11>
The absorbent unit is formed in a rectangular shape long in the longitudinal direction in a state before use, and the length of the absorbent unit in the lateral direction is preferably 0.5 mm or more and 10 mm or less. The sheet-like material as described in any one of>-<10>.
<12>
The absorbent unit is formed in a rectangular shape long in the longitudinal direction in a state before use, and the longitudinal length of the absorbent unit is preferably 20 times or more with respect to the lateral length. The sheet-like material according to any one of <1> to <11>, which is not more than twice, more preferably not less than 40 times and not more than 80 times.
<13>
The absorbent unit is formed in a rectangular shape that is long in the vertical direction before use, and the length in the vertical direction of the absorbent unit is preferably 10 mm or more and 500 mm or less, more preferably 200 mm or more and 400 mm or less. The sheet-like material according to any one of the above items <1> to <12>.
<14>
The size relationship of the lateral length of the absorbent unit with respect to the width of the long base portion is preferably 0 μm <(Lx−W2) <1400 μm, more preferably 200 μm <(Lx−W2). ) The sheet-like material according to any one of <1> to <13>, which is <1000 μm.
<15>
The sheet-like material has a length in the longitudinal direction of preferably 100 mm to 1000 mm, and a length in the lateral direction of 50 mm to 300 mm, according to any one of <1> to <14>. Sheet-like material.
<16>
The ratio of the absorption area to the whole sheet is 20% or more from the viewpoint of easy absorption of the liquid in the fixed area of the particles of the water absorbing polymer in plan view of the sheet before use. The sheet according to any one of the above <1> to <16>, which is preferably 50% or more, more preferably 100% or less, and still more preferably 90% or less State.
<17>
When arranging the longitudinal direction of the absorptive unit to be the longitudinal direction of the sheet-like material, it is preferable that three or more absorptive units 4 be disposed per sheet-like material, 50 or more The sheet according to any one of <1> to <16>, further preferably disposed, and preferably disposed 1000 or less, and further preferably disposed 500 or less. State.
<18>
The ratio of the width of the elongate base portion to the width of the sheet-like material is the amount of the water-absorbing polymer supported on the elongate base portion, swelling inhibition, flexibility, air permeability, maintenance of the sheet shape, etc. From the viewpoint, the value is preferably 0.001 or more, more preferably 0.002 or more, preferably 0.200 or less, and still more preferably 0.040 or less. The sheet-like article as described in any one of <17>.
<19>
The width of the elongated base portion is preferably 0.3 mm or more, more preferably 0.6 mm or more, and preferably 10.0 mm or less, and 2.0 mm or less. Is more preferable, and it is still more preferable that it is 1.8 mm or less, The sheet-like object in any one of said <1>-<18>.
<20>
The hydrophilicity of the skin-facing surface of the elongated base portion, that is, the contact angle of ion exchange water with the constituent fibers forming the skin-facing surface is preferably 80 ° or more, and more preferably 90 ° or more. The sheet-like material according to any one of <1> to <19>, which is preferably 180 ° or less, and more preferably 120 ° or less.

<21>
The hydrophilicity of the non-skin facing surface of the elongated base portion, that is, the contact angle of ion-exchanged water with respect to the constituent fibers forming the non-skin facing surface is preferably 0 ° or more, and 30 ° or more. More preferably, the sheet-like material according to any one of <1> to <20>, preferably 90 ° or less, and more preferably 70 ° or less.
<22>
The difference between the contact angle of the skin-facing surface of the elongated base portion and the contact angle of the non-skin facing surface is preferably greater than 4 °, more preferably 5 ° or more, and even more preferably 7 ° or more. The sheet-like material according to any one of <1> to <21>, wherein the size is large, preferably 30 ° or less, more preferably 25 ° or less, and still more preferably 20 ° or less.
<23>
The sheet-like material according to any one of <1> to <22>, wherein the particles of the water-absorbing polymer are fixed to the surface of the elongated base portion via an adhesive.
<24>
The average particle diameter of the particles of the water-absorbing polymer in the state before use (before swelling) is preferably 20 μm or more, more preferably 200 μm or more, and preferably 700 μm or less, 500 μm or less The sheet-like material according to any one of the above <1> to <23>, further preferably.
<25>
The average particle diameter of the particles of the water-absorbing polymer in the swollen state is preferably 200 μm or more, more preferably 800 μm or more, preferably 3000 μm or less, and still more preferably 2000 μm or less. The sheet-like material as described in any one of said <1>-<24>.
<26>
The absorbent body for absorbent articles which has a sheet-like thing in any one of said <1> 1- <25>, and the liquid-permeable core wrap sheet which coat | covers this sheet-like thing.
<27>
The absorbent article which has an absorber as described in said <26>, the surface sheet distribute | arranged to the skin opposing surface side of this absorber, and the back surface sheet distribute | arranged to the non-skin opposing surface side of this absorber.

DESCRIPTION OF SYMBOLS 1 sheet-like material 2 elongate base part 2s side edge part 20 base material sheet 21 layer of non-skin opposing surface side with relatively high hydrophilicity 22 layer with relatively low hydrophilicity skin opposing surface side 3 water absorption Polymer (water-absorbing polymer particles)
DESCRIPTION OF SYMBOLS 4 Absorbent unit 5 Adhesive 100 Manufacturing apparatus 110 Base material sheet cut part 111a Cutter blade 111b Rotary die 112 Receiving roll 113 Slit apparatus 120 Adhesive application part 121 Application head 130 Water-absorbing polymer distribution part 131 Water-absorbing polymer introduction part 141 Vacuum Conveyor 145 vacuum box 151, 152 drive roll

Claims (11)

An elongated substrate portion having a transverse direction, a longitudinal direction longer than the transverse direction, and a thickness direction, and a water absorbing polymer fixed on the surface of the non-skin facing surface of the elongated substrate portion A sheet for an absorbent article, comprising a plurality of absorbent units having particles, wherein each of the absorbent units is arranged so that its longitudinal direction is in one direction,
The long base portion is a sheet-like material in which the hydrophilicity of the non-skin facing surface is higher than the hydrophilicity of the skin facing surface.   In the swollen state in which the particles of the water-absorbing polymer absorb the liquid, the particles of the water-absorbing polymer swell beyond the side edge along the longitudinal direction of the long base portion, and the long The sheet-like material according to claim 1, wherein the position of the water-absorbing polymer particles in the substrate-like base is different from the position before absorbing the liquid in the thickness direction.   3. The water-absorbing polymer particles protrude beyond the side edges of the elongated substrate portion in a state before use before the water-absorbing polymer particles absorb the liquid. 4. Sheet-like material.   The said elongate base parts adjacent to each other in the state before use before the particle | grains of the said water-absorbing polymer absorb a liquid are adjacent at least in part, The said any one of Claims 1-3 Sheet-like material. The sheet-like object includes a non-slit region where a plurality of the elongated base portions are connected in the lateral direction at both ends in the longitudinal direction,
No particles of the water-absorbing polymer are disposed in the non-slit region,
The sheet-like material according to any one of claims 1 to 4, wherein both ends in the longitudinal direction of the sheet-like material are fixed to the absorbent article.   In the elongated base portion, the distance between both side edges along the longitudinal direction is larger than the average particle diameter of the state before the water absorbent polymer particles absorb the liquid, and the water absorbent polymer particles are The sheet-like material according to any one of claims 1 to 5, wherein the sheet-like material is smaller than the average particle diameter of a state in which the liquid is absorbed and swollen.   When the sheet-like material is viewed in a plan view, the particles of the water-absorbing polymer are unevenly distributed and fixed, and in the portion where the basis weight of the fixed particles of the water-absorbing polymer is relatively large, the elongated substrate The sheet-like object according to any one of claims 1 to 6, wherein a distance between both side edge portions along the longitudinal direction of the portion is relatively short.   The particles of the water-absorbing polymer are fixed only to the surface of the non-skin-facing surface of the elongated base portion before the particles of the water-absorbing polymer absorb the liquid. The sheet-like article as described in a term.   The sheet-like material according to any one of claims 1 to 8, wherein the elongated base portion is a non-woven fabric.   The absorbent body for absorbent articles which has the sheet-like material in any one of Claims 1-9, and the liquid-permeable core wrap sheet which coat | covers this sheet-like material. An absorbent article comprising the absorbent body according to claim 10, a surface sheet disposed on the skin-facing surface side of the absorbent body, and a back sheet disposed on the non-skin-facing surface side of the absorbent body.

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