JP2019042403A - Sheet for absorbent article and absorbent article - Google Patents

Abstract

To provide a sheet for an absorbent article which is excellent in body fluid absorbing property and is unlikely to give discomfort when it is in touch with the skin in a wet state, and an absorbent article using the same.SOLUTION: A sheet for an absorptive article 1 has a first surface 1S1 and a second surface 1S2, cellulosic fiber 3F including hydrophobic fiber 2F and cellulosic fiber 3F exists nearer on the first surface 1S1 and is exposed on the first surface 1S1. Cool contact feeling q-max in the state of moisture content 50 mass% is equal to or less than 2.5 kW/mor less both on the first surface 1S1 and on the second surface 1S2.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a sheet for an absorbent article suitable as a component of an absorbent article.

  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

  Absorbent articles such as disposable diapers and sanitary napkins are required to be excellent in absorbability of body fluids such as urine, menstrual blood and sweat, and to quickly excrete excreted body fluid and hold it in the absorbent body . In order to obtain an absorbent article that can meet such needs, it is important to consider the role of various components of the absorbent article and to select a sheet material that can sufficiently play that role. For example, the surface sheet, which is one of the components of the absorbent article, is disposed closer to the wearer's skin than the absorbent body, and receives the excreted body fluid first and has a chance to contact the wearer's skin. More than other components. Such a surface sheet is required to be excellent in the draw-in property of body fluid from the viewpoint of improving the body fluid absorbability of the absorbent article, and is uncomfortable for the wearer when touching the skin in a wet state. It is requested not to give. With regard to the latter property that does not cause discomfort, especially when the topsheet touches the wearer's skin, giving the wearer a cold feeling leads to discomfort. There is a need for a sheet for an absorbent article which is excellent in the ability to draw in body fluid and which is less likely to cause discomfort even when touching the skin in a wet state.

  Accordingly, an object of the present invention is to provide a sheet for an absorbent article which is excellent in the drawability of a body fluid and hardly gives an unpleasant feeling even when touching the skin in a wet state, and an absorbent article using the same.

The present invention is a sheet for an absorbent article, which has a first surface and a second surface opposite to the first surface, and which comprises a hydrophobic fiber and a cellulose fiber, wherein the cellulose fiber is the first surface. It is unevenly distributed on the side and exposed to the first surface, and the contact cooling feeling q-max in the state of water content 50 mass% is 2.5 kW / m for both the first surface and the second surface. It is a sheet for absorbent articles which is ² or less.
The present invention is also an absorbent article comprising the above-mentioned sheet for an absorbent article of the present invention.

The sheet for an absorbent article of the present invention is excellent in the ability to draw in body fluid, and is less likely to cause discomfort even when it comes in contact with the skin in a wet state.
Since the absorbent article of the present invention has a sheet for an absorbent article having such properties, it is excellent in body fluid absorbability and wearing feeling.

FIG. 1 is a schematic cross-sectional view along the thickness direction of the sheet for an absorbent article of the present invention. FIG. 2: is a schematic diagram which shows the apparatus (wet paper machine) which can be used for implementation of the manufacturing method of the sheet | seat for absorbent articles of this invention. FIG. 3 is an explanatory view of a method of measuring the liquid permeation time.

  The sheet for absorbent articles of the present invention comprises hydrophobic fibers and cellulosic fibers. Hydrophobic fibers are relatively less hydrophilic (more hydrophobic) and cellulosic fibers are relatively more hydrophilic (less hydrophobic). 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). The hydrophobic fibers constituting the sheet for an absorbent article of the present invention preferably have a contact angle with water of 90 degrees or more, and the cellulosic fibers preferably have a contact angle with water of less than 90 degrees and are hydrophilic. It is a fiber.

<Method of measuring contact angle>
The fiber is taken out from the object to be measured (sheet for absorbent article), 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.

  In addition, when the sheet | seat for absorbent articles is used as a structural member of an absorbent article, when taking out the said sheet | seat for absorbent articles and carrying out evaluation measurement, the structural member is another structure by an adhesive agent, a melt | fusion, etc. If it is fixed to the member, the fixed portion is removed after removing the adhesive force by a method such as blowing cold air of cold spray within a range not affecting the contact angle of the fiber. This procedure is common to all measurements herein.

The sheet for absorbent articles of the present invention comprises hydrophobic fibers and cellulosic fibers (hydrophilic fibers) having higher hydrophilicity, and these fibers are uniformly distributed throughout the sheet. Specifically, the cellulose-based fibers are unevenly distributed on the first surface side and exposed to the first surface. That is, the hydrophobic fibers are unevenly distributed on the second surface side of the sheet for an absorbent article of the present invention.

  The sheet | seat 1 for absorbent articles which is one Embodiment of the sheet | seat for absorbent articles of this invention is shown by FIG. The sheet 1 for an absorbent article has a first surface 1S1 and a second surface 1S2 located on the opposite side, and is configured to include a hydrophobic fiber 2F and a cellulosic fiber 3F, and the cellulosic fiber 3F is While being unevenly distributed on the one surface 1S1 side, it is exposed to the first surface 1S1. More specifically, the sheet 1 for an absorbent article has a structure in which the cellulose fiber layer 3 mainly composed of the cellulose fiber 3F is formed on one side of the hydrophobic fiber layer 2 mainly composed of the hydrophobic fiber 2F. The cellulose fiber layer 3 forms the first surface 1S1. One side of the hydrophobic fiber layer 2 is covered with the cellulose-based fiber layer 3 forming the first surface 1S1, while the other side of the hydrophobic fiber layer 2 is cellulose-based fiber. The layer 3 is not formed, only the hydrophobic fiber 2F is substantially exposed, and the second surface 1S2 of the sheet 1 for an absorbent article is a hydrophobic fiber layer in which the cellulosic fiber 3F is not exposed. It consists of the other side of 2. 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.

  The hydrophobic fiber layer 2 is preferably mainly composed of hydrophobic fibers 2F. The content of the hydrophobic fiber 2F in the hydrophobic fiber layer 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 is mainly composed of the cellulose-based fiber 3F, which is a hydrophilic fiber having a higher hydrophilicity than the hydrophobic fiber 2F, preferably a hydrophilic fiber having a contact angle with water of preferably less than 90 degrees, It functions as a hydrophilic fiber layer having higher hydrophilicity than the hydrophobic fiber layer 2 in the sheet 1 for an article. 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 sheet 1 for an absorbent article has a laminated structure in which the cellulose fiber layer 3 as a hydrophilic fiber layer is entirely laminated on one side of the hydrophobic fiber layer 2.

The sheet 1 for an absorbent article according to a preferred embodiment of the sheet 1 for an absorbent article has a laminated structure in which the hydrophilic fiber layer 3 is laminated on the hydrophobic fiber layer 2 as described above. 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 sheet for an absorbent article 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 a color, thickness, a mixture other than fibers, etc., the boundary is visually observed in the same direction because the state is clearly different in the thickness direction of the sheet for absorbent articles. If a gap or boundary that separates the same direction is recognized even if the condition is recognized, or if there is no difference in the condition in the same direction, that is defined as the boundary of each layer, and the sheet for the absorbent article is laminated. Judge as having a structure.
Thus, when it is judged that the sheet for an absorbent article has a laminated structure, whether or not the laminated structure includes the hydrophobic fiber layer and the hydrophilic fiber layer depends on the cellulose fiber contained in each layer (hydrophilic fiber And the other fiber types, and the content ratio of each fiber type based on the determination. 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 the layer in which the content ratio of the cellulose fiber is twice or more of the fibers other than the cellulose fiber is the "hydrophilic fiber layer", and the content ratio of the hydrophobic fiber is twice or more the cellulose fiber and other hydrophilic fibers. The layer which is the "hydrophobic fiber layer".

The basis weight of the hydrophilic fiber layer (cellulose-based fiber layer) and the hydrophobic fiber layer in the sheet for an absorbent article 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. When it can not be isolated, the thickness of each layer is measured from the photograph of the cross-sectional area of the sheet for an absorbent article, and the ratio is multiplied by the basis weight of the entire sheet for an absorbent article to determine the basis weight of each layer.
Further, in the sheet for an absorbent article having a laminated structure, the basis weight of the cellulose fiber and the hydrophobic fiber contained in each layer of the hydrophilic fiber layer and the hydrophobic fiber layer is each fiber determined by the above-mentioned JIS method Calculated by multiplying the content ratio of each layer by the basis weight of each layer.
In the case where the sheet for an absorbent article has a structure in which the boundary is not recognized in the sheet cross section along the thickness direction (direction orthogonal to the surface direction), that is, in the single layer structure, the single layer structure The basis weight of the cellulose-based fiber and the hydrophobic fiber is calculated by multiplying the basis weight of the entire sheet by the content ratio of each fiber obtained by the above-mentioned JIS method.

  Thus, in the sheet 1 for an absorbent article, the first surface 1S1 side is formed of the cellulose-based fiber layer 3 having relatively high hydrophilicity (low hydrophobicity), and the cellulose-based fibers 3F on the first surface 1S1 And the second surface 1S2 side is formed of the hydrophobic fiber layer 2 having relatively low hydrophilicity (high hydrophobicity), and the hydrophobic fiber 2F is exposed on the second surface 1S2. A hydrophilicity gradient is given in the thickness direction that "the first surface 1S1 side is relatively higher in hydrophilicity than the second surface 1S2 side". Therefore, the sheet | seat 1 for absorbent articles is excellent in the drawability of the liquid from 2nd surface 1S2 to 1st surface 1S1, and has strong capillary force. Therefore, when the absorbent article sheet 1 is used as a component (for example, a top sheet) of the absorbent article, the second surface 1S2, that is, the surface on which the hydrophobic fibers 2F are unevenly distributed is on the skin side of the wearer. By arranging the surface 1S1 where the cellulose fiber 3F is unevenly distributed toward the non-skin side, body fluids such as urine, menstrual blood, and sweat excreted from the wearer's body become the second surface 1S2. After contact, the first surface 1S1 is quickly drawn to the side, and as a result, liquid residue is unlikely to occur on the second surface 1S2 and the discomfort caused by touching the skin with the second surface 1S2 wet is worn Hard to give to

  One of the characteristics of the sheet 1 for an absorbent article is that the hydrophobic fiber layer 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 hydrophobic fiber layer 2 and the cellulose fiber layer 3 is mainly based on the hydrophobic fiber 2F of the hydrophobic fiber layer 2 and the cellulose fiber 3F of the cellulose fiber layer 3 without an adhesive. It is done by intertwining. However, as a result of the constituent fibers of the hydrophobic fiber layer 2 and / or the cellulose-based fiber layer 3 having adhesiveness in the laminated adhesion form of both, in addition to the entanglement of those 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 hydrophobic fiber layer 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 hydrophobic fiber It is obtained by supplying the slurry containing the cellulosic fiber 3F to the layer 2 to form the cellulosic fiber layer 3. It is judged by the following confirmation test whether the hydrophobic fiber layer 2 and the cellulose-based fiber layer 3 are in a close contact state due to the entanglement of fibers.

<Confirmation test of adhesion state>
First, it is confirmed by microscopic observation that no adhesive is present at the interface between both layers of the sample sheet (sheet 1 for absorbent article).
The sample sheet is cut into 5 cm squares and folded in two. The folded sheet is sandwiched between 10 cm square plates, the weight is placed, and the pressure is applied to 3 kPa. The sheet is allowed to stand for 10 seconds to open the fold. This operation is repeated a total of three times so that the folding direction is the same, and the folds are also in the same position. Prepare another 5 cm square sheet with this crease, immerse the sheet in liquid nitrogen for 10 seconds, and then use a sharp razor to cut the crease in the direction perpendicular to the crease at each of the three folds. Insert (bending test).
Next, the cut cross section of the cut is observed using an SEM or an optical microscope to confirm the presence or absence of a gap between the hydrophobic fiber layer 2 and the cellulose-based fiber layer 3, that is, the adhesion state. If there is a gap, measure the gap distance in the thickness direction of the gap portion. And if the average of the gap distance in all the cut sections is smaller than 1/2 of the average thickness of the sheet 1 for absorbent articles, both layers of the present invention are considered to be "in close contact" and 1 of the average thickness. If it is larger than / 2, it is said "not in close contact". That is, if both layers of the present invention are in a close contact state, the close contact state can be maintained even in a severe test such as the bending test, but if it is not in a close contact state, the gap distance becomes large by the bending test. . In addition, if the average of the gap distance is larger than 1⁄2 of the average thickness of the sheet 1 for an absorbent article which is much larger than the inter-fiber distance of each layer, it can be easily determined that a gap is formed. For example, while the fibers are strongly entangled and bound in each layer, when there is little contact or entanglement between the hydrophobic fiber 2F and the cellulosic fiber 3F between both layers, etc., the state in which both layers are in close contact It can be said that In such a sheet for an absorbent article (laminated sheet), there are many gaps locally, and furthermore, if the gaps (the attached state of the absorbent article, etc.) are easily formed by the force applied to the laminated sheet. Conceivable.

  In addition, when the area of a sample sheet (sheet 1 for absorbent articles) is less than 10 cm square, the bending mentioned above is performed so that it may become the same 3 kPa pressurization conditions, and the number of cuts for observing a cut section is also In the same manner, the confirmation test of the adhesion state is performed.

As described above, since the hydrophobic fiber layer 2 and the cellulose-based fiber layer 3 are in close contact with each other by entanglement of fibers without an adhesive, liquid permeability at the interface between both layers 2 and 3 is improved, and adhesion is achieved. The disadvantages of the use of the agent, for example, the decrease in water absorbency and flexibility of the absorbent article sheet 1 are prevented. Temporarily, when the hydrophobic fiber layer 2 and the cellulose fiber layer 3 are mutually bonded by the adhesive agent in the sheet | seat 1 for absorbent articles, the liquid permeability in the interface of the hydrophobic fiber layer 2 and the cellulose fiber layer 3 And the basis weight of the cellulose-based fiber layer 3 becomes difficult. In the latter case, the method for producing the sheet 1 for absorbent articles of the type using an adhesive as described above is the dry cellulose fiber produced separately in the dry hydrophobic fiber layer 2. The layer 3 is stacked and fixed with an adhesive, and the cellulose fiber layer 3 used in this step is required to have a certain level of strength (paper strength) so as not to break in the step. Naturally, the cellulosic fiber layer 3 needs to have a basis weight of a certain level or more, and it is difficult to adopt a thin cellulosic 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 described in the present embodiment, as described above, the absorbent article sheet 1 is in a form in which the hydrophobic fiber layer 2 and the cellulose-based fiber layer 3 are in close contact with each other by entanglement of fibers without an adhesive. Since the sheet 1 for absorbent articles can be manufactured without passing through the step of bonding the dry cellulose fiber layer 3 by using the wet paper-making method, it is difficult to handle in the step of bonding. It is possible to adopt the cellulose-based fiber layer 3 of the above, that is, the cellulose-based fiber layer 3 alone which is thin or has a small basis weight so as not to be realized as a sheet (paper). The basis weight can be improved.

The basis weight of the cellulose-based fiber layer 3 is not particularly limited, but even when the basis weight of the hydrophobic fiber layer 2 is considerably small, the above-described effects such as the liquid draw-in property can be exhibited. By reducing the basis weight of the cellulose-based fiber layer 3, the liquid permeability of the sheet 1 for an absorbent article can be improved, and the basis weight of the sheet 1 for an absorbent article can be reduced. When the absorbent article 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 as compared to the hydrophobic fiber layer 2, and more specifically, the basis weight of the cellulose fiber layer 3 and the hydrophobic fiber layer 2 The ratio to the basis weight of 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 hydrophobic fiber layer 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 cellulose-based fiber layer 3 is preferably more than 0 g / m ² , more preferably 0.1 g / m ² or more, more preferably 0.5 g / m ² or more, particularly preferably 1 g / m ² or more, Preferably it is 10 g / m < ² > or less, More preferably, it is 8 g / m < ² > or less, More preferably, it is 7 g / m < ² > or less, Especially preferably, it is 5 g / m < ² > or less.

  As hydrophobic fiber 2F which constitutes hydrophobic fiber layer 2, hydrophobic thermoplastic fiber (heat fusion textile) can be used. In the hydrophobic fiber layer 2, one kind of hydrophobic fiber 2F can be used alone or in combination of two or more kinds. 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 hydrophobic fiber layer 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 lamination of a plurality of sheets It may be a structure. A long fiber non-woven fabric can be exemplified as an example of the form of the hydrophobic fiber layer 2, and in this case, the hydrophobic fiber 2F mainly forming the long fiber non-woven fabric is a long fiber. 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 fiber 2F in the hydrophobic fiber layer 2 is preferably 50% by mass or more based on the total mass of the hydrophobic fiber layer 2 from the viewpoint of imparting sufficient hydrophobicity to the hydrophobic fiber layer 2 More preferably, it is 70% by mass or more, and, for example, additives such as oil agents for imparting properties such as slipperiness and hydrophilicity required at the production stage of the hydrophobic fiber layer 2 which is a non-woven fabric, strength is maintained The amount is preferably 98% by mass or less, more preferably 90% by mass or less, from the viewpoint of including a binder or the like.

  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 such a thickness or basis weight that the cellulose-based fiber layer 3 can be separated as, for example, a sheet of paper from the absorbent article sheet 1. That is, the cellulose-based fiber layer in the sheet for an absorbent article of the present invention may be a very thin to low basis weight layer which is difficult to separate by peeling off from the hydrophobic fiber layer.

  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.

In the sheet for an absorbent article of the present invention, the cellulose-based fibers may be unevenly distributed on the first surface side and exposed to the first surface, and the layer configuration thereof is the sheet for an absorbent article shown in FIG. The boundary is recognized from the cross section of the sheet along the thickness direction (the direction orthogonal to the surface direction) without being limited to the laminated structure of the hydrophobic fiber layer 2 and the cellulose fiber layer 3 (hydrophilic fiber layer) as in 1. There may be no structure (single layer structure). As an example of the sheet for an absorbent article having such a single layer structure, a form in which the cellulose-based fibers gradually increase from the second surface to the first surface, in other words, hydrophobicity from the second surface to the first surface There is a form in which the sex fibers gradually decrease. In an example of the sheet for an absorbent article having such a single layer structure, only the cellulose-based fibers may be exposed on the first surface having the largest basis weight of the cellulose-based fibers, or in addition to the cellulose-based fibers A smaller amount of hydrophobic fibers may be exposed, and only hydrophobic fibers are exposed in the absence of cellulose-based fibers on the second surface with the lowest basis weight of the cellulose-based fibers. Alternatively, in addition to the hydrophobic fibers, a smaller amount of cellulosic fibers may be exposed.

  Such a form in which the gradient of the distribution amount of the cellulose fiber is given in the thickness direction is not only a sheet for an absorbent article having a single layer structure but also a laminated structure (a structure in which the boundary is recognized from the sheet cross section) It can also be in the sheet for absorbent articles of And the sheet | seat for absorbent articles of the single layer structure or laminated structure which has such a form is obtained by utilizing a wet papermaking method so that it may mention later. Specifically, for example, a slurry containing cellulosic fibers is supplied to a hydrophobic fiber layer containing only hydrophobic fibers as constituent fibers to form a formed sheet (a sheet for an absorbent article having a single layer structure of a wet sheet). In the paper making process, a suction means such as a suction box is disposed on the side opposite to the supply side of the slurry so that the water in the slurry is sucked and dewatered, and the suction force of the suction and dewatering is appropriately adjusted. The distribution amount of the cellulose-based fiber in the thickness direction of the hydrophobic fiber layer can be adjusted. The cellulose fiber can be penetrated in the thickness direction of a hydrophobic fiber layer as the suction power of such suction dehydration is strong, and the sheet for an absorbent article having a single layer structure or a laminated structure thus obtained In, the cellulose fiber exists in the whole thickness direction. Moreover, in the sheet for absorbent articles of the single layer structure or the laminated structure manufactured using such a wet papermaking method, the hydrophobic fiber and the cellulose fiber are present in an entangled manner, which results from this. Thus, the entire sheet has high liquid permeability in the thickness direction.

In the sheet for an absorbent article of the present invention, the cellulose-based fibers (hydrophilic fibers) are unevenly distributed on the first surface side (hydrophobicity) in either the laminated structure as shown in FIG. 1 or the single-layer structure described above. Due to the fact that the fibers are localized on the second surface side), it has the features of being excellent in the drawability of the body fluid from the second surface side to the first surface side, and in the liquid permeability. In the sheet for an absorbent article of the present invention, the contact cooling sensation q-max in the state of the moisture content of 50% by mass is 2.5 kW / m ² or less on both the first surface and the second surface, which is caused by this It also has the feature of being less likely to cause discomfort even when touching the skin in a wet state.

A skin sensation that feels cold when the skin touches an object is called contact coldness. This contact coolness differs depending on the amount of heat transfer from the skin to the object when the skin touches the object, and the more the amount of heat transfer, the cooler the touch. The contact cooling sensation q-max corresponds to the maximum value of the amount of heat transfer from the skin to the object, and the value of the contact cooling sensation q-max is larger as it feels cold when touching the object, It becomes smaller as you feel warm. The sheet for an absorbent article of the present invention in a wet state, specifically with a moisture content of 50% by mass, has a contact cooling sensation q-max of 2.5 kW / m ² or less on both the first surface and the second surface. Therefore, for example, when it is applied to an absorbent article, the surface of the first and second surfaces directed to the skin side of the wearer (preferably, opposite to the first surface on which the cellulose fibers are unevenly distributed) Even if the second surface (side) comes in contact with the body fluid to touch the skin of the wearer when it is wet, it is difficult for the wearer to feel cold and uncomfortable. The lower limit of the contact cooling sensation q-max of each of the first surface and the second surface in the state of the moisture content of 50% by mass of the sheet for an absorbent article is not particularly limited, and is preferably as small as possible, but in general It is 1 kW / m ² or more.

The measurement of the contact cooling sensation q-max can be measured according to a conventional method using a commercially available measuring device. Specifically, in the measurement of contact cooling sensation q-max, heat is stored in a heating plate such as a metal plate with a temperature sensor, and the temperature of the heating plate is set to a temperature higher than that of the object to be measured. By contacting the surface of the object to be measured and measuring the maximum value of the heat flow when the heat stored in the hot plate moves to the object on the low temperature side immediately after the contact, the maximum value being It is the contact cooling sensation q-max of the said measurement object. The measurement of the contact cooling sensation q-max can be performed by the following method using a commercially available measuring device, specifically, for example, “KES-F7-II accurate rapid thermal physical property measuring device” manufactured by Kato Tech Co., Ltd. .

<Method of measuring contact sensation q-max>
The object to be measured (sheet for absorbent article) is left under an environment of room temperature 23 ° C. and relative humidity 50% for 2 hours or more, and under such environment, KATO TEC KES-F7-II is used to carry out The contact sensation q-max of the object to be measured is measured in accordance with the measurement manual made in Japan. Specifically, for example, a pure copper plate having an area of 9.0 cm ² and a mass of 9.8 g is used as the heat plate to be brought into contact with the measurement object, and the initial temperature of the copper plate is 33 ° C. (10 ° C. higher than the surface temperature of the measurement object) Temperature), the copper plate is brought into contact with the surface to be measured (the first surface or the second surface of the sheet for an absorbent article), with the contact pressure of the copper plate to the measurement object being 1 kPa. With the value of heat flow being zero, the maximum value of the heat flow is measured. This measurement is performed five times for the measurement target surface, and the average value of the plurality of measurement values is defined as the contact cooling sensation q-max of the measurement target surface.

  In the “contact cooling sensation q-max of the sheet for an absorbent article in the state of a water content of 50% by mass” focused on in the present invention, the water content is 50% by mass per one measurement target (sheet for an absorbent article) Prepare a plurality of samples having a predetermined range (for example, a moisture content in the range of about 10 to 60% by mass) and different moisture contents from one another, and contacting the first surface and the second surface according to the method for each sample It is calculated | required by measuring cooling sensation q-max and obtaining the graph of "(water content)-(contact cooling sensation q-max)" about each surface. That is, by drawing an approximate curve from this graph, the contact cooling sensation q-max at a water content of 50% by mass can be obtained for the surface to be measured. More specifically, for example, a plurality of samples are prepared for one measurement target (sheet for absorbent article), and the plurality of samples are sprayed with water by spraying to obtain a water-containing state. The amount of water sprayed on the samples at this time is set to be different among the samples. Then, for each of the plurality of water-containing samples, a portion thereof is dried to measure the bone-dry weight, and the sample weight after 1 minute after the water spray is measured, and from the measured values of both weights, the sample Calculate the moisture content at 1 minute after water spray of water. In addition, with respect to each of the plurality of samples, after 1 minute after water spraying, the contact cooling sensation q-max of each of the first surface and the second surface is measured by the above-mentioned method. And about the measuring object (sheet for absorbent articles) which is a supply source of a plurality of samples by plotting the moisture content of each of a plurality of samples, and the contact cooling feeling q-max of each of the 1st and 2nd surfaces The graph of "(moisture content)-(contact cooling feeling q-max)" of is obtained.

The method for making the contact cooling sensation q-max in the state of the moisture content of 50% by mass of the sheet for an absorbent article be 2.5 kW / m ² or less on both the first surface and the second surface is the effect of the present invention Although it is not particularly limited as long as it is not impaired, in general, when the content of cellulosic fibers (hydrophilic fibers) such as wood pulp increases, the value of contact cooling sensation q-max tends to increase, so the basis weight of cellulosic fibers It is effective to reduce the amount of water to the extent that it does not substantially affect the liquid draw-in and permeability. Also, in general, when the content of hydrophobic fibers such as thermoplastic fibers increases, the value of the contact cooling sensation q-max tends to decrease.

The basis weight of the cellulose-based fiber of the sheet for an absorbent article of the present invention is a sheet of the absorbent article of the present invention from the viewpoint of setting the contact cooling feeling q-max in the state of water content 50 mass% to the specific range Preferably, it is 0.1 g / m ² or more, more preferably 1 g / m ² or more, and preferably 8 g / m ² or less, more preferably 5 g / m ² or less.
From the same viewpoint, in the sheet for an absorbent article of the present invention, the basis weight of the hydrophobic fiber is preferably 5 g / m ² or more, more preferably 8 g / m ² or more, and preferably 20 g / m ² or less More preferably, it is 15 g / m ² or less.
The basis weight of each of the constituent fibers described above is the basis weight of the constituent fibers in the entire sheet, regardless of whether the sheet for an absorbent article has a single-layer structure or a laminated structure. The basis weight of the constituent fibers is calculated by the method described above.

In the sheet for an absorbent article of the present invention, it is premised that the first side and the second side both have a contact cooling feeling q-max of 2.5 kW / m ² or less at a water content of 50% by mass. The contact cooling sensation q-max may be the same or different. However, in the sheet for an absorbent article of the present invention, the cellulose-based fibers (hydrophilic fibers) are unevenly distributed on the first surface side (hydrophobic fibers are unevenly distributed on the second surface side), and basically the first surface Since the fiber configuration is different from that of the second surface, the contact cooling sensation q-max in the state of the water content of 50% by mass is usually different from each other.

  Further, in the sheet for an absorbent article of the present invention, as in the sheet 1 for an absorbent article shown in FIG. 1, for example, the cellulose fibers 3F are unevenly distributed on the first surface 1S1 side and exposed to the first surface 1S1. Body fluid from the second surface 1S2 side to the first surface 1S1 side due to the fact that (the hydrophobic fiber 2F is unevenly distributed to the second surface 1S2 side and exposed to the second surface 1S2) The arrangement in the absorbent article which is excellent in the draw-in property and liquid permeability of the absorbent article and which utilizes the features of the absorbent article sheet 1 is such that the body fluid excreted by the wearer first contacts the second surface 1S2. It is preferable to arrange the second surface 1S2 toward the skin side of the wearer. Then, the second surface 1S2 of the absorbent article sheet 1 has many opportunities to contact the wearer's skin in a wet state, so the second surface 1S2 is worn in a wet state on the first surface 1S1 or more. There is a need for properties that are less likely to cause discomfort even when touching the skin of a person. Considering the above, the second surface of the sheet for an absorbent article, which is directed to the skin side when used as a component of an absorbent article, has a moisture content of 50% by mass relative to the first surface. It is preferable that the contact cooling feeling q-max of is small. In this respect, in the sheet for an absorbent article of the present invention, the cellulose fibers having a relatively strong tendency to increase the value of the contact cooling feeling q-max are unevenly distributed on the first surface side, and basically on the second surface side. Is not present at all, or only a small amount is present, so the second surface tends to have a small contact cooling q-max at a moisture content of 50% by mass relative to the first surface. .

  The sheet for an absorbent article of the present invention is useful as a component of an absorbent article used for absorbing body fluid such as urine, soft stools, menstrual blood, and sweat which are discharged from the human body. Examples of the absorbent article to which the absorbent article sheet of the present invention can be applied include a spreadable or pants-type disposable diaper, a sanitary napkin, a sanitary short, an incontinence pad, and the like.

  The present invention includes an absorbent article having the above-described absorbent article sheet of the present invention. The basic composition of the absorbent article of the present invention is the same as that of the conventional absorbent article of this type, and typically, it is a liquid-permeable top sheet disposed relatively close to the skin of the wearer And a back sheet impervious to liquid or impervious to liquid or water repellant disposed relatively far from the skin of the wearer, and a liquid retaining absorbent core interposed between both sheets. . In the absorbent article having such a configuration, the placement position of the sheet for an absorbent article of the present invention is not particularly limited, but the features of the sheet for an absorbent article (excellent in body fluid drawability and contact with the skin in a wet state) But it is preferable that the sheet for an absorbent article be disposed at a position closer to the skin of the wearer than the absorbent core from the viewpoint that the discomfort is hardly given). For example, a core sheet that covers the outer surface of the surface sheet, an absorbent core, and a second sheet (a sub that is interposed between the surface layer and the absorbent core (the absorbent body composed of the absorbent core and the core surface)) It is suitably used as a layer etc.

In the absorbent article having the absorbent article sheet according to the present invention, as described above, the absorbent article sheet is contact cooled in the state where the second surface is 50% by mass relative to the first surface. It is preferable that the feeling q-max is small and the second surface is disposed toward the skin side of the wearer. By doing so, the second surface of the sheet for an absorbent article comes in contact with body fluid and gets wet, and even when touching the skin of the wearer of the absorbent article in the wet state, the wearer feels cold and uncomfortable feeling. It becomes difficult to give Further, as described above, since the sheet for an absorbent article of the present invention is excellent in the ability to draw in body fluid from the second surface side to the first surface side and the liquid permeability, the second surface is the skin side of the wearer It is also useful in terms of improving the liquid absorbability of the absorbent article.

  Hereinafter, the method for producing the sheet for an absorbent article of the present invention will be described by taking the method for producing the sheet 1 for an absorbent article having a laminated structure shown in FIG. 1 as an example. FIG. 2 shows a wet paper machine 30 that can be used to make the absorbent article 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 sheet 1 for absorbent articles supplies the slurry which contains the cellulose fiber 3F to the hydrophobic fiber layer 2, forms the cellulose fiber layer 3 partially on one side of the hydrophobic fiber layer 2 by sheet-forming. And a dividing step of cutting the sheet 1 for an absorbent article obtained through the sheet forming step at a predetermined position and dividing the sheet into a plurality of pieces. The hydrophobic fiber layer 2 used in such a production method is, as described above, a sheet-like material mainly composed of hydrophobic fibers (for example, all the constituent fibers are hydrophobic fibers), for example, spunbonded nonwoven fabric etc. Long-fiber non-woven fabric. More specifically, the method of manufacturing the sheet 1 for an absorbent article comprises a dewatering step of dewatering the formed sheet 40 obtained in the above-described papermaking process, and drying of the formed sheet 40 after the dewatering to obtain an absorbent article. A drying step for obtaining the sheet 1 and a winding step for winding the obtained absorbent article sheet 1 are included. The formed sheet 40 obtained in the paper making process is the sheet 1 for the absorbent article in a wet state, and this is dewatered and dried to form the formed sheet 40 in a dried state, a sheet for an absorbent article which is a production object It is 1.

  In the wet paper machine 30, as shown in FIG. 2, first, the hydrophobic fiber layer 2 wound in a roll is continuously unwound, and the surface to be laminated of the cellulose fiber layer 3 (sheet for absorbent article The sheet 1) is placed on the papermaking net 31 with the one surface 1S1 of 1 being directed upward and conveyed in one direction. Then, the slurry containing the cellulose-based fibers 3F is supplied from the slurry supply device 32 to the upper surface of the hydrophobic fiber layer 2 on the papermaking mesh 31 during conveyance thereof, ie, the planned layering surface of the cellulose-based fiber layer 3 The cellulose-based fiber layer 3 is formed on the entire top surface of the fiber layer 2 (paper making process). The water in the supplied slurry sequentially passes through the hydrophobic fiber layer 2 and the papermaking mesh 31 and flows down from the lower side of the papermaking mesh 31, and fiber components including the cellulose-based fibers 3F in the slurry are hydrophobic fibers. The entangled fibers (hydrophobic fibers 2F) of the layer 2 stay in the hydrophobic fiber layer 2, whereby the cellulose fiber layer 3 containing the cellulose fibers 3F on one side of the hydrophobic fiber layer 2 on the papermaking network 31 A molded sheet 40 (wet absorbent sheet 1) having a laminated structure is formed.

  In the wet paper machine 30, as shown in FIG. 2, 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 in the paper making process, the slurry is formed to be hydrophobic. When the cellulose fiber layer 3 is formed on the fiber layer 2, the water in the slurry is sucked and dewatered by the suction box 33. If 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 papermaking mesh 31 side, and depending on the suction power and the basis weight of the hydrophobic fiber layer 2, etc. The cellulose-based fibers 3 F can be penetrated in the thickness direction of the hydrophobic fiber layer 2. Therefore, in the case of producing the sheet for an absorbent article having a single layer structure described above, more specifically, the sheet for an absorbent article having a single layer structure in which the cellulosic fibers gradually increase from the second surface to the first surface. It is preferable that the paper making process has a process of suction-dehydrating water in the slurry containing the cellulose-based fibers 3F supplied to the hydrophobic fiber layer 2.

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. 2, 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. In the embodiment shown in FIG. 2, dewatering and drying of the formed sheet 40 are performed separately, but the above-described dewatering method and drying method may be combined appropriately to perform both steps simultaneously. By thus dewatering and drying the formed sheet 40, the absorbent article sheet 1 can be obtained.

  The continuous band-shaped absorbent article sheet 1 thus obtained is taken up by the winding roll 38 to be a roll-like wound product (winding step). In addition, before winding up the sheet | seat 1 for absorbent articles in roll shape, you may post-process the sheets 1 for absorbent articles, such as a crepe process, as needed.

  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. For example, in the sheet 1 for an absorbent article shown in FIG. 1, the whole area of one surface of the hydrophobic fiber layer 2 is covered with the cellulose fiber layer 3, but the range in which the effect of the present invention is not impaired In particular, if a certain level of liquid draw-in property and liquid permeability are ensured, and the contact cooling sensation q-max in the state of water content 50 mass% falls within the specific range, the hydrophobic fiber layer Only a part of one side of 2 may be coated with the cellulosic fiber layer 3. Further, the following appendices will be disclosed regarding the embodiment of the present invention described above.

<1>
What is claimed is: 1. A sheet for an absorbent article, having a first side and a second side opposite to the first side, the sheet comprising hydrophobic fibers and cellulosic fibers,
The cellulose-based fiber is unevenly distributed on the first surface side and exposed to the first surface,
The sheet | seat for absorbent articles whose contact-cooling feeling q-max in the state of water content 50 mass% is 2.5 kW / m < ² > or less with the said 1st surface and the said 2nd surface.

<2>
Contact sensation q-max in the state of water content of 50% by weight, the absorbent article sheet according to <1> is 1 kW / m ² or more on the first surface and the second surface both.
<3>
The sheet | seat for absorbent articles as described in said <1> or <2> with which the said 2nd surface is smaller than the said 1st surface in which the said cooling sensation q-max is small.
<4>
It has a structure in which a cellulose-based fiber layer mainly composed of the cellulose-based fiber is formed on one side of a hydrophobic fiber layer mainly composed of the hydrophobic fiber, and the hydrophobic fiber layer and the cellulose-based fiber layer The sheet | seat for absorbent articles of any one of said <1>-<3> which has closely_contact | adhered by the entanglement of fiber, and this cellulose type fiber layer forms the said 1st surface.
<5>
The sheet for an absorbent article according to <4>, wherein the hydrophobic fiber layer and the cellulose-based fiber layer are in close contact with each other without an adhesive.
<6>
The sheet | seat for absorbent articles of any one of said <1>-<5> which the said cellulose fiber is exposed to the said 2nd surface.
<7>
The basis weight of the cellulose fiber is 0.1 g / m ² or more and 8 g / m ² or less, preferably 1 g / m ² or more, and preferably 5 g / m ² or less. The sheet | seat for absorbent articles of any one of <6>.
<8>
The sheet according to any one of <1> to <7>, wherein the basis weight of the cellulose-based fiber is 1 g / m ² or more and 5 g / m ² or less.
<9>
The basis weight of the hydrophobic fibers, wherein at 5 g / ^{m 2} or more 20 g / ^{m 2} or less <1> absorbent article sheet according to any one of to <8>.
<10>
The basis weight of the hydrophobic fibers, an absorbent article sheet according to any one of 8 g / ^{m 2} or more 15 g / ^{m 2} or less is the <1> to <9>.
<11>
The sheet for an absorbent article according to any one of <1> to <10>, wherein the contact angle of the hydrophobic fiber with water is 90 degrees or more, preferably 100 degrees or more.
<12>
The sheet for an absorbent article according to any one of the above <1> to <11>, wherein the contact angle of the cellulose fiber with water is less than 90 degrees, preferably less than 70 degrees, more preferably less than 40 degrees. .

<13>
A cellulose fiber layer mainly composed of the cellulose fiber is formed on one side of a hydrophobic fiber layer mainly composed of the hydrophobic fiber,
The ratio of the basis weight of the cellulose fiber layer to the basis weight of the hydrophobic fiber layer 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 sheet | seat for absorbent articles of any one of said <1>-<12> which is .4 or less.
<14>
A cellulose fiber layer mainly composed of the cellulose fiber is formed on one side of a hydrophobic fiber layer mainly composed of the hydrophobic fiber,
The ratio between the basis weight of the cellulose-based fiber layer and the basis weight of the hydrophobic fiber layer is 0.1 or more and 0.4 or less as the former / latter, any one of the above <1> to <13> The sheet | seat for absorbent articles as described in-.
<15>
A cellulose fiber layer mainly composed of the cellulose fiber is formed on one side of a hydrophobic fiber layer mainly composed of the hydrophobic fiber,
The basis weight of the cellulose fiber layer is preferably more than 0 g / m ² , more preferably 0.1 g / m ² or more, more preferably 0.5 g / m ² or more, particularly preferably 1 g / m ² or more, , preferably 10 g / ^{m 2} or less, more preferably 8 g / ^{m 2} or less, more preferably 7 g / ^{m 2} or less, wherein <1> to any one of <14> particularly preferably 5 g / ^{m 2} or less The sheet | seat for absorbent articles as described in-.
<16>
A cellulose fiber layer mainly composed of the cellulose fiber is formed on one side of a hydrophobic fiber layer mainly composed of the hydrophobic fiber,
The sheet for an absorbent article according to any one of <1> to <15>, wherein the basis weight of the cellulose-based fiber layer is 1 g / m ² or more and 5 g / m ² or less.
<17>
The sheet for an absorbent article according to <15> or <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 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 sheet for an absorbent article according to any one of <1> to <17>, wherein the polyolefin comprises polyethylene and polypropylene, the polyester comprises polyethylene terephthalate, and the polyamide comprises nylon 6 and nylon 66.
<19>
A cellulose fiber layer mainly composed of the cellulose fiber is formed on one side of a hydrophobic fiber layer mainly composed of the hydrophobic fiber,
The sheet | seat for absorbent articles of any one of said <1>-<18> whose said hydrophobic fiber layer is a long fiber nonwoven fabric.
<20>
The sheet | seat for absorbent articles of any one of said <1>-<19> which the said hydrophobic fiber and the said cellulose fiber smaller than that are exposed to the said 2nd surface.
<21>
Any one of the above <1> to <20>, in which only the cellulose-based fiber is exposed or the cellulose-based fiber and a smaller amount of the hydrophobic fiber are exposed on the first surface The sheet | seat for absorbent articles as described in a term.

<22>
The absorbent article which has a sheet | seat for absorbent articles of any one of said <1>-<21>.
<23>
In the sheet for an absorbent article, the second surface is smaller in the cooling sensation q-max as compared to the first surface, and the second surface is disposed toward the skin side of the wearer. The absorbent article as described in 22>.
<24>
A surface sheet disposed relatively near the skin of the wearer, a back sheet disposed relatively distant from the skin of the wearer, and a liquid-retaining absorbent core interposed between the two sheets Equipped with
The absorbent article according to <22> or <23>, wherein the sheet for an absorbent article is disposed at a position closer to the skin of the wearer than the absorbent core.
<25>
A core wrap sheet (skin-side core wrap sheet) for covering the outer surface (skin facing surface) of the absorbent core, and a second sheet interposed between the absorbent core and the surface sheet;
The absorbent article according to <24>, wherein at least one or more of the surface sheet, the core wrap sheet, and the second sheet include the absorbent article sheet.

  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 and 2]
A sheet for absorbent articles 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 hydrophobic fiber layer of 300 mm in width (CD length) 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 hydrophobic fiber layer. A formed sheet was obtained by forming a cellulose-based fiber layer having a predetermined basis weight over the entire area of one surface of the hydrophobic fiber layer. 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 an absorbent article sheet having a width of 260 mm.

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 sheet for absorbent articles of Examples 1 and 2. As the hydrophobic fiber layer, a spunbond nonwoven fabric (long-fiber nonwoven fabric) with a basis weight of 9 g / m ² , in which only hydrophobic fibers made of polypropylene resin are used as constituent fibers, was used. The papermaking speed at the time of wet papermaking was 10 m / min.

Comparative Example 1
Do not use a hydrophobic fiber layer, but apply the above slurry onto a papermaking net (usual paper making method), and use a paper with a basis weight of 13.5 g / m ² mainly containing cellulosic fibers, A sheet was produced in the same manner as in Example 1 to obtain Comparative Example 1.

Comparative Example 2
A spunbond nonwoven fabric having a basis weight of 9 g / m ^{2 and} having only hydrophobic fibers as constituent fibers, which was used as the hydrophobic fiber layer in the production of the sheet for absorbent articles of Examples 1 and 2, was taken as Comparative Example 2 as it was.

Comparative Example 3
A sheet for an absorbent article was produced in the same manner as in Examples 1 and 2 except that the basis weights of the hydrophobic fiber layer and the cellulose-based fiber layer were changed, and it was set as Comparative Example 3.

Comparative Example 4
A sheet obtained by laminating two sheets in a dry state was used as a sheet for an absorbent article of Comparative Example 4. Specifically, a basis weight of 10 g / m ^{2 in} which only NBKP is a constituent fiber on one side of a spun bond nonwoven fabric (long fiber non-woven fabric) having a basis weight of 15 g / m ² having only hydrophobic fibers consisting of polypropylene resin as constituent fibers. A sheet of the absorbent article of Comparative Example 4 was obtained by laminating the above-mentioned papers without an adhesive.

〔Evaluation test〕
About the sheet for absorbent articles of each example and comparative example, the contact cooling feeling q-max of the sheet surface (the surface of a cellulose-based fiber layer, the surface of a hydrophobic fiber layer) in the state of water content 50 mass% by the said method Were evaluated, and the touch evaluation and the measurement of liquid permeation time were performed by the following method. The results are shown in Table 1 below. The liquid permeation time is an index of the liquid permeability of the sheet, and the shorter the liquid permeation time, the better the liquid permeability of the sheet and the higher the evaluation.

<Method of tactile evaluation>
The tactile sensation evaluation of the sheet for absorbent articles of each example and comparative example was performed by five specialist panels engaged in the study of the texture of the non-woven fabric. Specifically, the sheet for an absorbent article to be evaluated was placed on the table with the first side up, and the special panel evaluated the tactile sensation by touching the surface of the first side with fingers. . The atmosphere of the test room evaluated was 23 ° C. and 50% RH. The sensory value of the sheet (high evaluation standard sheet) which does not feel coldness and maintains a sense of smoothness 3.0, contrary to the coldest feeling and stickiness, the feeling of discomfort is maintained by a sheet with poor feeling (low evaluation standard sheet) A sensory value of 1.0 was set as a standard, and the sensory value of the tactile sensation was evaluated in increments of 0.5 according to the following evaluation standard while making a relative comparison between the other examples and comparative examples with both standard sheets. As the high evaluation reference sheet, a dry sheet which is the same sheet as in Comparative Example 2 and which has not been provided with water and which has been allowed to stand at 23 ° C., 50% RH for 2 hours or more is separately prepared. As a sheet, a dry sheet which was the same as Comparative Example 1 and which was left undisturbed at 23 ° C. and 50% RH for 2 hours or more without adding water was separately prepared. Three sheets were evaluated for each sheet for absorbent articles, and the average value of the sensory values of all the panels was taken as the sensory value of the touch evaluation of the sheet for absorbent articles. When this sensory value was 2.5 or more, it was judged that the feel was comfortable due to smooth feeling without feeling coldness, and if it was less than 2.5, the feel was uncomfortable due to cold or stickiness.
(Evaluation criteria for sensory evaluation of tactile sensation)
3: There is little feeling of coldness and a smooth feeling continues and does not feel uncomfortable.
2: It feels somewhat uncomfortable due to the coldness at the moment of touch, but does not last long.
1: It feels cold and sticky, and discomfort continues.

<Method of measuring liquid permeation time>
As shown in FIG. 3, two cylinders 91 and 92 with an inner diameter of 35 mm, whose upper and lower ends are open, are arranged up and down with the axes of both cylinders 91 and 92 aligned, and an object of measurement of 8 cm square with a diameter of 55 mm. The sheet S (sheet for absorbent article) is sandwiched between the upper and lower cylinders 91, 92. At this time, it is preferable that the clip 93 be fitted to the annular flange portion provided on the lower end of the upper cylinder 91 and the upper end of the lower cylinder 92 to connect the upper and lower cylinders 91 and 92. The code | symbol 94 is packing made of rubber etc. which has a through-hole same diameter as the internal diameter of the cylinders 91 and 92, and the same shape. In this manner, in a state in which the sheet S to be measured is sandwiched and fixed by the upper and lower cylinders 91 and 92, a saline solution (an aqueous solution having a sodium chloride concentration of 0.9 mass%) indicated by symbol W in FIG. ) 40 g ± 1 g at a time. The supplied saline passes through the measurement target sheet S or is absorbed by the measurement target sheet S and disappears from inside the upper cylinder 91. Measure the time until the water surface of the physiological saline becomes the same position as the surface of the measurement target sheet S (surface on the upper side of the cylinder 91) from the start of supply of physiological saline, and let that time be the liquid permeation time . The measurement is performed three times, and the average value is taken as the measurement value. The measurement target sheet S is replaced with a new one every time the measurement is performed.

As shown in Table 1, the sheet for an absorbent article of each example has a short liquid permeation time, is excellent in liquid permeability and body fluid drawability, and has a contact cooling feeling q- in a state of a water content of 50% by mass. Due to the max being 2.5 kW / m ² or less on both sides, the sensory value of the touch evaluation was high, and it did not feel cold and uncomfortable when actually touched with a finger in such a wet state.
On the other hand, although the liquid permeation time is short, the sheet for an absorbent article of Comparative Example 1 which does not contain a hydrophobic fiber has the contact cooling feeling q-max of more than 2.5 kW / m ² and it is actually in the wet state I felt cold and uncomfortable when I touched it with my fingers.
Further, the sheet for an absorbent article of Comparative Example 2 which does not contain a cellulose-based fiber (hydrophilic fiber) has a small value of the contact cooling feeling q-max and is cold and unpleasant when it is actually touched with a finger in a wet state. Although it did not feel, the liquid permeation time was long, and the result was inferior in liquid permeability and body fluid drawability.
Moreover, as for the sheets for absorbent articles of Comparative Examples 3 and 4, all of the basis weight of the whole sheet, in particular, the basis weight of the cellulose fiber layer is large, and the contact cooling feeling q-max is the first surface. It is surmised that both the second and third surfaces are larger than in the example, and the liquid permeation time is also longer. Further, from the comparison between Comparative Example 3 and Comparative Example 4, the liquid permeability as in Comparative Example 3 in which entanglement between the cellulose fiber and the hydrophobic fiber is caused by wet papermaking is more than the lamination of a simple dry sheet. It can be seen that it is advantageous in terms of improvement of

1 sheet for absorbent article 1S1 first side of sheet for absorbent article 1S2 second side of sheet for absorbent article 2 hydrophobic fiber layer 2F hydrophobic fiber 3 cellulose fiber layer 3F cellulose fiber 30 wet paper machine 31 paper making Net 32 Slurry Feeder 33 Suction Box 34, 36 Belt Conveyor 35 Press Roll 37 Yankee Dryer 38 Winding Roll 40 Forming Sheet

Claims (8)

What is claimed is: 1. A sheet for an absorbent article, having a first side and a second side opposite to the first side, the sheet comprising hydrophobic fibers and cellulosic fibers,
The cellulose-based fiber is unevenly distributed on the first surface side and exposed to the first surface,
The sheet | seat for absorbent articles whose contact-cooling feeling q-max in the state of water content 50 mass% is 2.5 kW / m < ² > or less with the said 1st surface and the said 2nd surface.   The sheet for an absorbent article according to claim 1, wherein the second face has a smaller contact cooling feeling q-max compared to the first face.   It has a structure in which a cellulose-based fiber layer mainly composed of the cellulose-based fiber is formed on one side of a hydrophobic fiber layer mainly composed of the hydrophobic fiber, and the hydrophobic fiber layer and the cellulose-based fiber layer The sheet for an absorbent article according to claim 1 or 2, which is adhered by entanglement of fibers, and the cellulose-based fiber layer forms the first surface.   The sheet for an absorbent article according to any one of claims 1 to 3, wherein the cellulose-based fiber is exposed to the second surface. The basis weight of the cellulose type fiber is 0.1 g / m ² or more and 8 g / m ² or less, The sheet for an absorbent article according to any one of claims 1 to 4. The basis weight of the hydrophobic fibers, an absorbent article sheet according to claim 1 is 5 g / ^{m 2} or more 20 g / ^{m 2} or less.   The absorbent article which has a sheet | seat for absorbent articles of any one of Claims 1-6.   In the sheet for an absorbent article, the second surface is smaller in the contact sensation q-max as compared to the first surface, and the second surface is disposed toward the skin side of the wearer. The absorbent article as described in 7.

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