Absorbent article, sheet for absorbent article, and method for manufacturing same

Abstract

An absorbent article (1) has a front surface sheet (2), a non-skin-side sheet (3) positioned on a non-skin side relative to the front surface sheet (2), and a liquid film cleaving agent (4) disposed between both the sheets (2), (3). The front surface sheet (2) and the non-skin-side sheet (3) are joined by an adhesive (5). The liquid film cleaving agent (4) is disposed between the adhesive (5) and the front surface sheet (2) or the non-skin-side sheet (3) such that there is a site (E1) where the adhesive (5) and the front surface sheet (2) or the non-skin-side sheet (3) are directly joined. The adhesive (5) is preferably applied in a stripe shape or a spiral shape. The liquid film cleaving agent (4) is preferably disposed intermittently along the adhesive (5). The distance between adjacent liquid film cleaving agents (4) is preferably 3 mm to 30 mm inclusive.

Description

Absorbent articles, sheets for absorbent articles, and methods for manufacturing the same

[0001] The present invention relates to absorbent articles, sheets for absorbent articles, and methods for manufacturing the same.

[0002] In absorbent articles, to reduce liquid residue on the surface sheet and improve dryness after liquid absorption, the applicant previously proposed a nonwoven fabric to which a liquid film cleavage agent was attached (see Patent Documents 1 and 2). This liquid film cleavage agent is an agent that inhibits the formation of liquid films between the constituent fibers of the nonwoven fabric or on the surface of the constituent fibers and / or cleaves the formed liquid films, and can exert such effects on human excretions such as menstrual blood and urine.

[0003] Patent Document 1 describes the use of a nonwoven fabric, manufactured by coating the surface of the nonwoven fabric with a liquid film-breaking agent, as a surface sheet. Patent Document 2 describes an absorbent article manufactured by coating the non-skin side of a surface sheet with a liquid film-breaking agent.

[0004] Japanese Patent Publication No. 2017-214694 US2020 / 0383844A1

[0005] The present invention relates to an absorbent article. In one embodiment, it is preferable to have a surface sheet, a non-skin side sheet located on the non-skin side of the surface sheet, and a liquid film cleavage agent disposed between the two sheets. In one embodiment, it is preferable that the surface sheet and the non-skin side sheet are joined by an adhesive. In one embodiment, it is preferable that the liquid film cleavage agent is disposed between the adhesive and the surface sheet or the non-skin side sheet such that there is a portion where the adhesive and the surface sheet or the non-skin side sheet are directly joined.

[0006] The present invention also relates to a sheet for absorbent articles. In one embodiment, it is preferable to have a surface sheet, a non-skin side sheet located on the non-skin side of the surface sheet, and a liquid film cleavage agent disposed between the two sheets. In one embodiment, it is preferable that the surface sheet and the non-skin side sheet are joined by an adhesive. In one embodiment, it is preferable that the liquid film cleavage agent is disposed between the adhesive and the surface sheet or the non-skin side sheet such that there is a portion where the adhesive and the surface sheet or the non-skin side sheet are directly joined.

[0007] The present invention also relates to a method for manufacturing a sheet for absorbent articles, wherein a surface sheet and a non-skin side sheet are joined together by an adhesive. In one embodiment, it is preferable to include a first step of applying the adhesive to the skin side of the non-skin side sheet or the non-skin side of the surface sheet; a second step of applying a liquid film cleavage agent on the adhesive; and a third step of arranging the surface sheet or the non-skin side sheet on the adhesive and joining the surface sheet and the non-skin side sheet via the adhesive. In one embodiment, it is preferable in the second step to apply the liquid film cleavage agent on the adhesive such that there is a portion where the adhesive and the surface sheet or the non-skin side sheet are directly joined.

[0008] Figure 1 is a schematic cross-sectional view showing a transverse cross-section of one embodiment of an absorbent article comprising the absorbent article sheet of the present invention. Figure 2 is a schematic plan view showing the skin side of the non-skin side sheet in the absorbent article shown in Figure 1. Figure 3 is a schematic diagram showing one embodiment of a method for manufacturing an absorbent article comprising the absorbent article sheet of the present invention. Figures 4(a) to (c) show other embodiments of the non-skin side sheet shown in Figure 2, and are schematic plan views showing the skin side of these sheets. Figure 5 shows another embodiment of the non-skin side sheet shown in Figure 2, and is a schematic plan view showing the skin side of this sheet. Figure 6 shows another embodiment of an absorbent article comprising the absorbent article sheet of the present invention, and is a schematic cross-sectional view showing a transverse cross-section of the absorbent article. Figure 7 shows another embodiment of an absorbent article comprising the absorbent article sheet of the present invention, and is a schematic cross-sectional view showing a transverse cross-section of the absorbent article. Figure 8 is a schematic plan view of a sanitary napkin made in Example 2, viewed from the side of the surface sheet. Detailed description of the invention

[0009] There is a demand for absorbent sheets with improved dryness, and in recent years, there has also been a demand for the successful manufacture of such absorbent sheets. Specifically, during the manufacture of absorbent sheets, depending on the placement of the liquid film cleavage agent on the sheet, the liquid film cleavage agent may adhere to manufacturing equipment such as rollers and cutters, causing equipment contamination. Furthermore, if the liquid film cleavage agent is placed without considering the placement area of ​​the adhesive that joins the surface sheet to other components, and the adhesive is not exposed, the adhesive strength may decrease. Therefore, the present invention relates to an absorbent article, an absorbent sheet, and a method for manufacturing the same, which have improved dryness while suppressing equipment contamination caused by the liquid film cleavage agent.

[0010] The present invention will be described below with reference to the drawings, based on preferred embodiments thereof. Figure 1 schematically shows a cross-section of one embodiment of the absorbent article 1 of the present invention. This absorbent article 1 comprises an absorbent article sheet 10.

[0011] The absorbent article sheet 10 shown in Figure 1 comprises a surface sheet 2, a non-skin side sheet 3 located on the non-skin side of the surface sheet 2, and a liquid film cleavage agent 4 placed between the two sheets 2 and 3. By combining the absorbent article sheet 10 with other components described later, an absorbent article 1 can be constructed. Details of the liquid film cleavage agent 4 will be described later. In this specification, "skin side" refers to the side of the absorbent article that faces the wearer's body when worn. "Non-skin side" refers to the side of the absorbent article that is on the opposite side of the surface sheet from the skin side when worn.

[0012] The surface sheet 2 is the sheet material located closest to the skin in the absorbent article sheet 10. The surface sheet 2 consists of a single sheet material or a laminate of multiple sheet materials. In either case, it is preferable that each sheet material is made of fiber sheets. It is also preferable that the surface sheet 2 as a whole is permeable to liquids. As long as the surface sheet 2 as a whole is permeable to liquids, it is permissible that a portion of the sheet material constituting the surface sheet 2 includes sheet materials other than fiber sheets, such as perforated film.

[0013] The non-skin side sheet 3 is a general term for the sheet materials that make up the absorbent article sheet 10, which are located on the non-skin side of the surface sheet 2 and face the surface sheet 2. The non-skin side sheet 3 consists of a single sheet material or a laminate of multiple sheet materials. In either case, it is preferable that each sheet material is made of a liquid-permeable nonwoven fabric or paper. It is also preferable that the non-skin side sheet 3 as a whole is liquid-permeable. As long as the non-skin side sheet 3 as a whole is liquid-permeable, it is permissible for a part of the sheet materials that make up the non-skin side sheet 3 to include a sheet material other than a fiber sheet, such as a perforated film.

[0014] As shown in Figures 1 and 2, an adhesive 5 is applied between the surface sheet 2 and the non-skin side sheet 3. The surface sheet 2 and the non-skin side sheet 3 are joined by the adhesive 5. In this embodiment, three lines of adhesive 5 are applied linearly along the longitudinal direction X of the absorbent article sheet 10. In other words, the adhesive is applied in a stripe pattern. Each of the striped adhesive lines 5 is spaced apart in the transverse direction Y of the absorbent article sheet 10. In a plan view of the absorbent article 1, the adhesive 5 is located at a distance from the periphery of the absorbent body 6, which will be described later, and inward from the periphery. In this specification, "longitudinal direction" refers to the direction that coincides with the front-to-back direction of the wearer when the absorbent article 1 equipped with the absorbent article sheet 10 is worn. "Transverse direction" refers to the direction perpendicular to the longitudinal direction of the absorbent article 1. In other words, the longitudinal direction X and the transverse direction Y coincide between the absorbent article sheet 10 and the absorbent article 1.

[0015] As adhesives, various adhesives conventionally used for absorbent articles can be used, and for example, hot-melt adhesives are preferably used. Examples of hot-melt adhesives include styrene-based and olefin-based adhesives. As styrene-based hot-melt adhesives, it is preferable to use styrene-butadiene-styrene copolymer (SBS), styrene-isoprene-styrene copolymer (SIS), styrene-ethylene-butylene-styrene copolymer (SEBS), which is a hydrogenated product of SBS, and blended hot-melt adhesives made by blending two or more of these.

[0016] In the absorbent article sheet 10 of this embodiment, it is preferable that the liquid film cleavage agent 4 is arranged in a predetermined form. In this specification, "liquid film cleavage agent" refers to an agent that can inhibit the formation of a liquid film between the fibers or on the fiber surface of a fiber sheet such as a nonwoven fabric or paper. The liquid film is typically formed when a liquid such as body fluid comes into contact with the fiber sheet. The liquid film cleavage agent typically has the action of cleaving the formed liquid film and the action of inhibiting the formation of a liquid film, with the former being the primary action and the latter being the secondary action. The cleavage of the liquid film is achieved by the action of the liquid film cleavage agent, which pushes aside a part of the liquid film layer and destabilizes it. Due to the action of this liquid film cleavage agent, the liquid can easily pass through without remaining in the narrow region between the fibers of the fiber sheet. Therefore, a fiber sheet containing a liquid film cleavage agent has excellent liquid permeability. For example, if the constituent fibers of nonwoven fabrics and paper are made thinner and the distance between fibers is reduced, the nonwoven fabrics and paper will have a softer texture, but there is a concern that liquid residue may easily form. However, by applying a liquid film cleavage agent to the surface of the constituent fibers of the nonwoven fabrics and paper, this concern can be eliminated, and a fiber sheet can be obtained that achieves both a soft texture and suppression of liquid residue.

[0017] The liquid film cleavage agent 4 generally exists in liquid form under the usage environment of the absorbent article 1. In Figure 1, the liquid film cleavage agent 4 is shown as being placed on the absorbent article sheet 10 in droplet form, but this is a schematic diagram for illustrative purposes only, and in reality, it does not have to be placed in droplet form. In other words, the liquid film cleavage agent 4 may be partially absorbed by other adjacent members and not in droplet form. The liquid film cleavage agent 4 can be absorbed, for example, by the surface sheet 2, the non-skin side sheet 3, and the adhesive 5.

[0018] As shown in Figures 1 and 2, it is preferable that the liquid film cleavage agent 4 is placed at predetermined locations on the absorbent article sheet 10 to form liquid film cleavage portions 41. In the embodiments shown in these figures, the absorbent article sheet 10 has a row of liquid film cleavage portions 42 on a single stripe-shaped adhesive 5 (i.e., on the surface of the adhesive 5 facing the surface sheet 2), where droplet-shaped liquid film cleavage portions 41 form a linear sequence of points along the vertical direction X. The rows of liquid film cleavage portions 42 are placed on each adhesive 5. The direction in which the rows of liquid film cleavage portions 42 extend coincides with the direction in which the adhesive 5 extends. In other words, the liquid film cleavage agent 4 is arranged in a scattered manner (i.e., intermittently) along the direction in which the adhesive 5 extends. In a plan view of the absorbent article 1, both side edges of each liquid film rupture portion 41 forming the liquid film rupture portion row 42 are located inward in the lateral direction Y than both side edges of the adhesive 5, or the side edges of each liquid film rupture portion 41 coincide with both side edges of the adhesive 5. Both ends of the liquid film rupture portions 41 forming the liquid film rupture portion row 42 are located inward in the vertical direction X than both ends of the adhesive 5 in the vertical direction X. Therefore, in a plan view of the absorbent article 1, the arrangement of the liquid film rupture portion row 42 and the arrangement of the adhesive 5 completely overlap. In other words, the liquid film rupture portion row 42 exists only on the adhesive 5.

[0019] As shown in Figures 1 and 2, the surface sheet 2 and the liquid film cleavage agent 4 are in direct contact. Similarly, the liquid film cleavage agent 4 and the adhesive 5 are in direct contact. The adhesive 5 and the non-skin side sheet 3 are directly bonded. The absorbent article 1 also has a portion E1 where the adhesive 5 and the surface sheet 2 are in direct contact, and a portion E2 where the liquid film cleavage agent 4 is interposed between the adhesive 5 and the surface sheet 2. Thus, in this embodiment, it is preferable that the liquid film cleavage agent 4 is arranged between the adhesive 5 and the surface sheet 2 so that there is a portion E1 where the adhesive 5 and the surface sheet 2 are directly bonded.

[0020] The advantages of having the liquid film cleavage agent 4 between the adhesive 5 and the surface sheet 2 in the absorbent article sheet 10 of this embodiment are as follows. In this embodiment, the surface sheet 2 and the liquid film cleavage agent 4 are in direct contact, allowing the liquid film cleavage agent 4 to penetrate between the fibers or onto the fiber surface of the fiber sheet constituting the surface sheet 2. Due to this liquid film cleavage agent 4, the surface sheet 2 becomes highly permeable to liquid. As a result, the absorbent article sheet 10 having the surface sheet 2 exhibits improved drying properties after liquid absorption. Furthermore, in this embodiment, the adhesive 5 and the surface sheet 2 are directly joined to a portion E1 without the liquid film cleavage agent 4, improving the adhesion between the surface sheet 2 and the non-skin side sheet 3. As a result, the shape retention of the absorbent article sheet 10, and by extension the absorbent article 1 equipped therewith, is improved.

[0021] From the viewpoint of further highlighting the above advantages, it is preferable that the liquid film rupture portion 41 is located at least in the central area in the longitudinal direction X of the absorbent article sheet 10, and more preferably that it extends along the longitudinal direction X from the front area through the central area to the rear area. The central area is located in the center of the longitudinal direction X of the absorbent article 1, which has a longitudinal direction X and a transverse direction Y and is long in one direction, and is the part that faces the wearer's excretory area when the absorbent article 1 is worn. The front area is located ventrally to the wearer's excretory area when the absorbent article 1 is worn, and the rear area is located dorsally to the wearer's excretory area when the absorbent article 1 is worn.

[0022] In each liquid film cleavage agent 4 arranged in the striped adhesive 5, it is preferable that the distance between adjacent liquid film cleavage agents 4 is within a predetermined range. Specifically, when the distance between adjacent liquid film cleavage agents 4 in the vertical direction X is denoted as D1, from the viewpoint of improving the shape retention of the absorbent article sheet 10 and, by extension, the absorbent article 1, the distance D1 is preferably 3 mm or more, more preferably 4 mm or more, and even more preferably 5 mm or more. Furthermore, from the viewpoint of improving the drying properties after liquid absorption, the distance D1 is preferably 30 mm or less, more preferably 20 mm or less, and even more preferably 15 mm or less. Considering the above, from the viewpoint of improving the shape retention of the absorbent article sheet 10 and, by extension, the absorbent article 1, and from the viewpoint of improving the drying properties after liquid absorption, the distance D1 is preferably 3 mm or more and 30 mm or less, more preferably 4 mm or more and 20 mm or less, and even more preferably 5 mm or more and 15 mm or less. The distance D1 is the distance between the two ends of the liquid film cleavage agent 4 in the vertical direction X. If the distance D1 is not constant, it is preferable that the minimum distance D1 is within the range described above. When D2 is the distance between adjacent liquid film cleavage agents 4 in the lateral direction Y, from the viewpoint of improving the shape retention of the absorbent article sheet 10 and by extension the absorbent article 1, the distance D2 is preferably 3 mm or more, more preferably 4 mm or more, and even more preferably 5 mm or more. Furthermore, from the viewpoint of improving the drying properties after liquid absorption, the distance D2 is preferably 30 mm or less, more preferably 20 mm or less, and even more preferably 15 mm or less. Considering the above, from the viewpoint of improving the shape retention of the absorbent article sheet 10 and by extension the absorbent article 1, and from the viewpoint of improving the drying properties after liquid absorption, the distance D2 is preferably 3 mm or more and 30 mm or less, more preferably 4 mm or more and 20 mm or less, and even more preferably 5 mm or more and 15 mm or less. The distance D2 is the distance between the side edges of the liquid film cleavage agents 4 in the lateral direction Y. If the distance D2 is not constant, it is preferable that the minimum distance D2 is within the range described above.

[0023] In this embodiment, the dimensions of the striped adhesive 5 are preferably within a predetermined range. Specifically, when the length of the striped adhesive 5 in the vertical direction X is W1, from the viewpoint of improving the shape retention of the absorbent article sheet 10 and, by extension, the absorbent article 1, the length W1 is preferably 10 mm or more, more preferably 20 mm or more, and even more preferably 30 mm or more. Also, from the viewpoint of improving liquid permeability, the length W1 is preferably 400 mm or less, more preferably 300 mm or less, and even more preferably 250 mm or less. If the length W1 of each adhesive 5 is not constant, it is preferable that the minimum length W1 is within the above range. When the length of the striped adhesive 5 in the horizontal direction Y is W2, from the viewpoint of improving the shape retention of the absorbent article sheet 10 and, by extension, the absorbent article 1, the length W2 is preferably 0.5 mm or more, more preferably 1 mm or more, and even more preferably 1.5 mm or more. Also, from the viewpoint of improving liquid permeability, the length W2 is preferably 10 mm or less, more preferably 7 mm or less, and even more preferably 5 mm or less. Considering the above, from the viewpoint of improving the shape retention and liquid permeability of the absorbent article sheet 10 and, by extension, the absorbent article 1, the length W2 is preferably 0.5 mm or more and 10 mm or less, more preferably 1 mm or more and 7 mm or less, and even more preferably 1.5 mm or more and 5 mm or less. If the length W2 of each adhesive 5 is not constant, it is preferable that the minimum length W2 is within the above range.

[0024] In this embodiment, it is preferable that the distance between adjacent adhesives 5 is within a predetermined range. Specifically, when D3 is the distance between adjacent adhesives 5 in the lateral direction Y, from the viewpoint of improving liquid permeability, the distance D3 is preferably 3 mm or more, more preferably 5 mm or more, and even more preferably 8 mm or more. Furthermore, from the viewpoint of improving the shape retention of the absorbent article sheet 10 and by extension the absorbent article 1, the distance D3 is preferably 30 mm or less, more preferably 25 mm or less, and even more preferably 20 mm or less. Considering the above, from the viewpoint of improving liquid permeability and improving the shape retention of the absorbent article sheet 10 and by extension the absorbent article 1, the distance D3 is preferably 3 mm or more and 30 mm or less, more preferably 5 mm or more and 25 mm or less, and even more preferably 8 mm or more and 20 mm or less. The distance D3 is the distance between the side edges of the adhesives 5 in the lateral direction Y. If the distance D3 is not constant, it is preferable that the minimum distance D3 is within the above range.

[0025] It is preferable that a predetermined amount of liquid film cleavage agent 4 is distributed in the absorbent article 1. The amount of liquid film cleavage agent 4 referred to here is the amount distributed throughout the entire absorbent article 1. In this embodiment, since all of the liquid film cleavage agent 4 is distributed on the adhesive 5, the amount of liquid film cleavage agent 4 described above is equal to the total amount of liquid film cleavage agent 4 distributed on the adhesive 5. Furthermore, as shown in Figures 4(c) and 5 described later, if the liquid film cleavage agent 4 is also distributed in areas other than the adhesive 5, the amount of liquid film cleavage agent 4 described above is the sum of the total amount of liquid film cleavage agent 4 distributed on the adhesive 5 and the total amount of liquid film cleavage agent 4 distributed in areas other than the adhesive 5. The "areas other than the adhesive" referred to here include, for example, the inner surface of the absorbent article 1, which is the non-skin side of the surface sheet 2, and the outer surface of the absorbent article 1, which is the skin side of the surface sheet 2, as shown in Figure 7 described later. From the viewpoint of improving dryness after liquid absorption, the amount of liquid film cleavage agent 4 is 0.1 g / m² relative to the area of ​​the absorbent article 1. ２ It is preferable that the amount is as described above, and more preferably 0.2 g / m². ２ The above is true, and more preferably 0.3 g / m ２ The above is preferable, and even more preferably 0.8 g / m２ That's all. Also, from the perspective of improving the shape retention of the sheet 10 for absorbent articles and, by extension, the absorbent article 1, the liquid film cracking agent 4 is 10.0 g / m ２ or less, more preferably 7.0 g / m ２ or less, still more preferably 5.0 g / m ２ or less, and even more preferably 3.0 g / m ２ or less. Considering the above, from the perspective of improving the dryness after liquid absorption and the shape retention of the sheet 10 for absorbent articles and, by extension, the absorbent article 1, the liquid film cracking agent 4 is 0.1 g / m ２ or more and 10.0 g / m ２ or less, more preferably 0.2 g / m ２ or more and 7.0 g / m ２ or less, still more preferably 0.3 g / m ２ or more and 5.0 g / m ２ or less, and even more preferably 0.8 g / m ２ or more and 3.0 g / m<​​​The amount of liquid film cleavage agent 4 distributed throughout the absorbent article 1 is measured, for example, by the following method. First, the absorbent article is observed under a microscope to measure the area of ​​the region where the surface sheet, absorbent material, and back sheet overlap in a plan view. Next, the absorbent article sheet is removed from the absorbent article using scissors or a cold spray. This is used as a test piece, and its mass is measured. The liquid film cleavage agent and other components such as adhesives attached to the test piece are eluted using a solvent such as ethanol and water. The total mass of the liquid film cleavage agent and other components is calculated from the mass of the eluate. After appropriately setting the measurement conditions such as the column and solvent, the eluate is separated and purified using liquid chromatography. The mass ratio of the liquid film cleavage agent to other components is calculated from the mass ratio of the purified product. The amount of liquid film cleavage agent is calculated based on the obtained mass ratio, the mass of the eluate, and the mass of the test piece. To determine which of the purified samples is a liquid film cleavage agent or other component, the molecular structure of the substance is identified based on the following identification method, and the corresponding structure is obtained and its physical properties are measured. The amount of liquid film cleavage agent distributed throughout the absorbent article is calculated based on the area calculated from the dimensions of the test specimen and the amount of liquid film cleavage agent. (Method for identifying molecular structure) The molecular weight of the separated product is measured using either mass spectrometry (MS) or gel permeation chromatography (GPC). １ H-NMR, １３ C-NMR or ２９ Using Si-NMR, the molecular framework of the separated product is identified; using IR, the functional groups it possesses are identified; and elemental analysis is used to determine the proportion of each element. All of this information is then combined to identify the molecular structure.

[0027] In this embodiment, a liquid film cleavage site 41 is formed by a droplet-shaped liquid film cleavage agent 4, and it is preferable that each liquid film cleavage site 41 contains a predetermined amount of the liquid film cleavage agent 4. Here, "each liquid film cleavage site 41" refers to one liquid film cleavage site 41 that constitutes a series of liquid film cleavage sites 42. When there are multiple liquid film cleavage sites 41 in a row, those with clear boundaries between adjacent liquid film cleavage sites 41 are targeted. Specifically, from the viewpoint of improving dryness after liquid absorption, it is preferable that each liquid film cleavage site 41 contains 0.01 mg or more of the liquid film cleavage agent 4, more preferably 0.03 mg or more, and even more preferably 0.05 mg or more. Furthermore, from the viewpoint of improving the shape retention of the absorbent article sheet 10 and by extension the absorbent article 1, it is preferable that each liquid film cleavage site 41 contains 2.0 mg or less of the liquid film cleavage agent 4, more preferably 1.0 mg or less, even more preferably 0.5 mg or less, and even more preferably 0.2 mg or less. Taking the above into consideration, from the viewpoint of improving the dryness after liquid absorption and improving the shape retention of the absorbent article sheet 10 and by extension the absorbent article 1, it is preferable that each liquid film cleavage site 41 contains 0.01 mg or more and 2.0 mg or less of the liquid film cleavage agent 4, more preferably 0.03 mg or more and 1.0 mg or less, even more preferably 0.05 mg or more and 0.5 mg or less, and even more preferably 0.05 mg or more and 0.2 mg or less.

[0028] The amount of liquid film cleavage agent 4 contained in each liquid film cleavage site 41 is measured, for example, by the following method. First, the liquid film cleavage sites are identified using a microscope or the like, and these are cut out from each sheet of absorbent material. The liquid film cleavage agent and other components such as adhesives are eluted from the sheet of absorbent material using a solvent such as ethanol and water. The total mass of the liquid film cleavage agent and other components is calculated from the mass of the eluate. After appropriately setting the measurement conditions such as the column and solvent, the eluate is separated and purified using liquid chromatography. The mass ratio of the liquid film cleavage agent to other components is calculated from the mass ratio of the purified product. Based on the obtained mass ratio and the mass of the eluate, the amount of liquid film cleavage agent is determined, and the amount of liquid film cleavage agent contained in each liquid film cleavage site is calculated. Which sample of the purified product is the liquid film cleavage agent or other components is determined by the same method as the "method for identifying molecular structure" described above.

[0029] In this embodiment, it is preferable that the total area S of the liquid film cleavage agents 4 arranged on the absorbent article sheet 10 in a plan view is within a predetermined range. Here, "area S" refers to the total area of ​​the liquid film cleavage agents 4 in a plan view within a square region of the absorbent article sheet 10 with sides of 31.6 mm. In this embodiment, since all the liquid film cleavage agents 4 are arranged on the adhesive 5, the above-mentioned area S is equal to the sum of the areas of all the liquid film cleavage agents 4 arranged on the adhesive 5. Furthermore, as shown in Figures 4(c) and 5 described later, if the liquid film cleavage agents 4 are also arranged in areas other than on the adhesive 5, then the above-mentioned area S is the sum of the sum of the areas of all the liquid film cleavage agents 4 arranged on the adhesive 5 and the sum of the areas of all the liquid film cleavage agents 4 arranged in areas other than on the adhesive 5. Here, "areas other than on the adhesive" refers to areas including, for example, the inner surface of the absorbent article 1, which is the non-skin side of the surface sheet 2, and the outer surface of the absorbent article 1, which is the skin side of the surface sheet 2, as shown in Figure 7 described later.

[0030] Specifically, from the perspective of improving the drying properties after liquid absorption, a 1000 mm absorbent sheet for absorbent articles is used. ２ The total area S of the liquid film cleavage agent 4 in a plan view per square region (with sides of 31.6 mm) is 3 mm². ２ Preferably, it is 10 mm or more２ It is even more preferable that the amount be greater than or equal to 20 mm ２ It is even more preferable that the amount be greater than or equal to 50 mm ２ It is even more preferable that the above be the case, 90 mm ２ The above is particularly preferable. Furthermore, from the viewpoint of improving the shape retention of the absorbent article sheet 10 and by extension the absorbent article 1, the absorbent article sheet 1000 mm ２ The total area S of the liquid film cleavage agent 4 in a plan view per square region (with sides of 31.6 mm) is 300 mm². ２ Preferably, it is 200 mm ２ It is even more preferable that the following be the case: 150 mm ２ The following is even more preferable. Considering the above, from the viewpoint of improving the drying properties after liquid absorption, and from the viewpoint of improving the shape retention of the absorbent article sheet 10 and by extension the absorbent article 1, the absorbent article sheet 1000 mm ２ The total area S of the liquid film cleavage agent 4 in a plan view per square region (with sides of 31.6 mm) is 3 mm². ２ 300mm or more ２ The following is preferable: 10 mm ２ 200mm or more ２ More preferably, the following is preferred: 20 mm ２ 200mm or more ２ It is even more preferable that the following be 50 mm ２ 150mm or more ２ It is even more preferable that the following conditions be met: 90 mm ２ 150mm or more ２ The following is particularly preferable:

[0031] The total area S of the liquid film cleavage agent 4 in a plan view is measured, for example, by the following method: The liquid film cleavage agent is made to contain a fluorescent paint (coumarin 6, manufactured by Sigma-Aldrich). In an absorbent article containing this liquid film cleavage agent, a UV-LED light (CONTEC PW-UV943H-04) is shone on the surface of the absorbent article sheet containing the liquid film cleavage agent in a dark place, and a fluorescence image is acquired with a digital camera (CANON IXY650). In the obtained fluorescence image, the area corresponding to the central area of ​​the absorbent article is cropped to a range of 31.6 mm × 31.6 mm. Using image analysis software (nexus New Qube), the area S of the liquid film cleavage agent is measured from the obtained image by creating a monochrome image with grayscale processing, discriminant analysis of the bright area with binary processing, and particle shape area analysis of the obtained area.

[0032] The absorbent article 1 of this embodiment further includes an absorbent body 6 on the non-skin side of the adhesive 5, in addition to the absorbent article sheet 10. The absorbent body 6 comprises an absorbent core 61. The absorbent core is composed of, for example, a stack of hydrophilic fibers such as cellulose including pulp, a mixed stack of the hydrophilic fibers and an absorbent polymer, a deposit of an absorbent polymer, or a laminated structure in which an absorbent polymer is supported between two absorbent sheets. The absorbent core 61 may also be covered with a liquid-permeable sheet (hereinafter referred to as "core wrap sheet") on at least its skin side, or the entire surface including the skin side and non-skin side may be covered with a core wrap sheet. In this embodiment, the absorbent body 6 comprises a non-skin side sheet 3 that covers the absorbent core 61, and the entire surface of the absorbent core 61 is covered with the non-skin side sheet 3. In other words, the non-skin side sheet 3 of this embodiment is typically a core wrap sheet.

[0033] The absorbent article 1 of this embodiment has a backing sheet 7 on the non-skin side of the absorbent body 6. For the backing sheet 7, for example, a liquid-impermeable film or a spunbond, meltblown, or spunbond laminated nonwoven fabric can be used. A liquid-impermeable film may be provided with a plurality of micropores to give the film water vapor permeability. To further improve the feel of the absorbent article 1 against the skin, a sheet with a good texture made of nonwoven fabric (not shown) may be laminated on the outer surface of the backing sheet 7. The absorbent body 6 and the backing sheet 7, as well as the surface sheet 2 and the backing sheet 7, are joined together, for example, with an adhesive.

[0034] The absorbent article 1 of this embodiment may have leak-proof cuffs (not shown) extending along the longitudinal direction X on both sides of the skin-facing side, depending on the specific application of the absorbent article. This effectively prevents liquid discharged onto the surface sheet 2 from leaking outwards along the surface sheet 2 in the lateral direction Y of the absorbent article 1. The absorbent article 1 may also have an adhesive layer (not shown) on the non-skin-facing surface. The adhesive layer is used to secure the absorbent article 1 to underwear or another absorbent article when it is being worn.

[0035] Examples of absorbent articles 1 having the above configuration include, but are not limited to, unfoldable disposable diapers, pant-type disposable diapers, sanitary napkins, and incontinence pads.

[0036] Next, the method for manufacturing the absorbent article 1 of this embodiment will be described with reference to Figure 3. This manufacturing method includes a method for manufacturing a sheet 10 for absorbent articles. The figure schematically shows a manufacturing apparatus 80 for the absorbent article 1. The manufacturing apparatus 80 shown in the figure includes a conveying section (not shown) for conveying the non-skin side sheet 3, an adhesive application section (not shown) for applying adhesive 5 to the skin side of the conveyed non-skin side sheet 3, a liquid film cleavage agent application section 81 for intermittently applying liquid film cleavage agent 4 on the adhesive 5 on the non-skin side sheet 3 to which the adhesive 5 has been applied, and a joining section 80A for overlapping and joining the surface sheet 2 on the non-skin side sheet 3 to which the liquid film cleavage agent 4 has been applied. The adhesive application section stores adhesive 5. The liquid film cleavage agent application section 81 stores liquid film cleavage agent 4. The liquid film cleavage agent application section 81 is installed downstream of the adhesive application section with respect to the conveying direction MD. The joint 80A is located downstream of the liquid film cleavage agent application section 81 with respect to the transport direction MD. In the manufacturing apparatus 80 shown in the figure, the transport direction MD is the direction in which the non-skin side sheet 3 is transported. The direction perpendicular to the transport direction MD is the width direction CD (not shown). The transport direction MD coincides with the longitudinal direction X of the absorbent article 1. The width direction CD coincides with the transverse direction Y of the absorbent article 1.

[0037] First, as shown in Figure 3, a long, strip-shaped backing sheet 7 is continuously unwound from a raw material roll (not shown), and the backing sheet 7 is transported along the transport direction MD by a conveyor (not shown). An absorbent body 6, which has adhesive (not shown) applied to its underside, is placed at intervals on the transported backing sheet 7, and the absorbent body 6 and the backing sheet 7 are joined together. In this embodiment, the absorbent body 6 is constructed by covering the entire surface of an absorbent core (not shown) with a non-skin side sheet 3 made of a core wrap sheet. As a result, the non-skin side sheet 3 and the backing sheet 7 are joined together, and the non-skin side sheet 3 is transported along the transport direction MD together with the backing sheet 7.

[0038] Next, the adhesive 5 is applied continuously along the transport direction MD to the skin side of the non-skin side sheet 3, which is transported together with the back sheet 7, using the adhesive application section (first step). In this embodiment, the adhesive 5 is applied in three stripes along the transport direction MD, with a constant interval along the width direction CD. In other words, the adhesive 5 is applied in a stripe pattern. The amount of adhesive 5 applied can be appropriately set according to the size of the non-skin side sheet 3. From the viewpoint of improving the shape retention of the absorbent article sheet 10 and, by extension, the absorbent article 1, it is preferable to apply the adhesive 5 so that it extends from the downstream side to the upstream side of the transport direction MD on the non-skin side sheet 3.

[0039] Next, the liquid film cleavage agent 4 is applied to the adhesive 5 using the liquid film cleavage agent application section 81 (second step). In this embodiment, the liquid film cleavage agent 4 is arranged in three strips along the transport direction MD, with a constant interval along the width direction CD. In other words, the liquid film cleavage agent 4 is applied to the adhesive 5 in the direction in which the adhesive 5 extends. In the embodiment shown in Figure 3, the liquid film cleavage agent 4 is applied intermittently along the transport direction MD. As a result, multiple liquid film cleavage sites 41 are formed in a scattered manner on the adhesive 5 of the non-skin side sheet 3, and multiple rows of liquid film cleavage sites 42 are formed by these liquid film cleavage sites 41. By applying the liquid film cleavage agent 4 in this way, when the surface sheet 2 is placed in the third step described later, the adhesive 5 and the surface sheet 2 will have areas where they are directly joined.

[0040] In the second step, the method for applying the liquid film cleavage agent 4 is not particularly limited, and various methods used in the manufacture of absorbent articles can be employed. Examples of such methods include inkjet printing, flexographic printing, hand-coating, gravure printing, and spray printing. Inkjet printing is a method of printing by spraying minute ink droplets from the nozzles of an inkjet head onto the material to be printed. Specific examples of this inkjet printing method include valve type, bubble jet (thermal jet) type, and piezo type. From the viewpoint of successfully applying the liquid film cleavage agent 4, it is preferable to employ the inkjet printing method. With the inkjet printing method, the area to which the liquid film cleavage agent 4 is applied can be easily controlled, so when the surface sheet 2 is placed in the third step described later, areas where the adhesive 5 and the surface sheet 2 are directly joined can be easily formed. For this reason, in this embodiment, an inkjet nozzle is used as the liquid film cleavage agent application section 81, and droplets of the liquid film cleavage agent 4 are sprayed from the inkjet nozzle 81 and applied onto the adhesive 5.

[0041] Next, a long surface sheet 2, which is continuously fed from a raw material roll (not shown) and conveyed in the conveying direction MD, is placed on the adhesive 5 of the non-skin sheet 3, and the surface sheet 2 and the non-skin sheet 3 are joined via the adhesive 5 (third step). The joining of the surface sheet 2 and the non-skin sheet 3 is performed using a joining section 80A. The joining section 80A is composed of a nip roll consisting of a guide roll 80G and an anvil roll (not shown) positioned opposite the guide roll 80G. The two sheets 2 and 3 are joined by being squeezed between the nip rolls forming the joining section 80A. In this way, an absorbent article sheet 10 is obtained. The absorbent article sheet 10 is conveyed downstream in the conveying direction MD by a conveyor 82.

[0042] In this manufacturing method, as shown in Figure 3, it is preferable to apply the liquid film cleavage agent 4 to the non-skin side of the surface sheet 2. As described above, it has been conventional practice to place a liquid film cleavage agent on the surface sheet in order to improve the drying properties after liquid absorption in absorbent articles. Furthermore, in order to effectively exert the effects of the liquid film cleavage agent, it was considered preferable to place the liquid film cleavage agent on the skin side of the surface sheet. On the other hand, when manufacturing such absorbent articles, if the liquid film cleavage agent is applied to the skin side of the surface sheet, i.e., the outer surface of the absorbent article, the liquid film cleavage agent may adhere to manufacturing equipment such as rollers and cutters, causing equipment contamination. In order to improve this point, the inventors diligently investigated and found that by placing the surface sheet 2 on the adhesive 5 to which the liquid film cleavage agent 4 is applied, the liquid film cleavage agent 4 is less likely to appear on the outer surface of the absorbent article sheet 10, and consequently the absorbent article 1. As a result, it was found that equipment contamination caused by the adhesion of the liquid film cleavage agent 4 to the manufacturing equipment can be suppressed.

[0043] As shown in Figure 3, in the second step, the liquid film cleavage agent 4 is intermittently applied to the adhesive 5 which is applied in a stripe pattern, so that the absorbent article sheet 10 has a portion E1 where the adhesive 5 and the surface sheet 2 are in direct contact, and a portion E2 where the liquid film cleavage agent 4 is interposed between the adhesive 5 and the surface sheet 2. According to this manufacturing method, an absorbent article sheet 10 is produced in which the surface sheet 2 and the non-skin side sheet 3 are joined by the adhesive 5. As described above, this absorbent article sheet 10 has improved dryness and shape retention after liquid absorption.

[0044] The resulting continuous mass of absorbent material is transported by conveyor 82 in the transport direction MD and cut by cutting section 83. This yields absorbent material 1. Various devices capable of intermittently cutting the continuous mass can be used as the cutting section 83. Such devices include, for example, a roll-shaped cutter having blades extending in the axial direction on its circumferential surface, a laser cutter, and a high-pressure water jet cutter. In this way, absorbent material 1 with improved dryness and shape retention after liquid absorption is manufactured.

[0045] Next, another embodiment of the present invention will be described with reference to Figures 4 to 7. The embodiments shown in these figures will be described in terms of differences from the embodiments shown in Figures 1 to 3 described earlier. For points not specifically described, the descriptions of the previous embodiments will apply as appropriate. Furthermore, in Figures 4 to 7, the same reference numerals are used for the same components as those shown in Figures 1 to 3.

[0046] The absorbent article sheet 10 shown in Figures 4(a) to 4(c) differs from the embodiment shown in Figure 2 in the arrangement of the liquid film cleavage agent 4 and the adhesive 5. Specifically, in the embodiment shown in Figure 4(a), the liquid film cleavage agent 4 is arranged linearly along the direction in which the striped adhesive 5 extends. Both side edges of the liquid film cleavage portion 41 arranged in this way are located inward in the lateral direction Y than both side edges of the adhesive 5, and the adhesive 5 is exposed outward from the side edges of the liquid film cleavage portion 41. Both ends of the liquid film cleavage portion 41 in the vertical direction X substantially coincide with both ends of the adhesive 5 in the vertical direction X. Therefore, the arrangement positions of the liquid film cleavage portion 41 and the arrangement positions of the adhesive 5 overlap in the thickness direction of the absorbent article sheet 10. In this embodiment as well, since the surface sheet 2 and the liquid film cleavage agent 4 are in direct contact, the drying properties after liquid absorption are improved due to the liquid film cleavage agent 4. Furthermore, because the length of the liquid film cleavage portion 41 in the lateral direction Y is shorter than the length of the adhesive 5 in the lateral direction Y, the absorbent article sheet 10 has a portion E1 where the adhesive 5 and the surface sheet 2 are directly joined without the liquid film cleavage agent 4, thus improving the shape retention of the absorbent article sheet 10, and by extension the absorbent article 1 equipped therewith.

[0047] From the viewpoint of further enhancing the above advantages, when the length of the adhesive 5 in the longitudinal direction X is W1 and the length of the liquid film cleavage portion 41 in the longitudinal direction X is W3, it is preferable that the ratio of length W3 to length W1, W3 / W1, is within a predetermined range. Specifically, from the viewpoint of improving the dryness after liquid absorption, the ratio W3 / W1 is preferably 0.05 or more, more preferably 0.1 or more, and even more preferably 0.2 or more. Furthermore, from the viewpoint of improving the shape retention of the absorbent article sheet 10 and by extension the absorbent article 1, the ratio W3 / W1 is preferably 0.8 or less, more preferably 0.6 or less, and even more preferably 0.4 or less. When the length W3 is not constant, the length W3 mentioned above refers to the minimum length W3.

[0048] Furthermore, when the length of the adhesive 5 in the lateral direction Y is W2 and the length of the liquid film cleavage portion 41 in the lateral direction Y is W4, it is also preferable that the ratio of length W4 to length W2, W4 / W2 (lateral length of liquid film cleavage agent / lateral length of adhesive), is within a predetermined range. Specifically, from the viewpoint of improving dryness after liquid absorption, the ratio W4 / W2 is preferably 0.01 or more, more preferably 0.05 or more, and even more preferably 0.1 or more. Also, from the viewpoint of improving the shape retention of the absorbent article sheet 10, and by extension the absorbent article 1, the ratio W4 / W2 is preferably 0.7 or less, more preferably 0.5 or less, and even more preferably 0.3 or less. Considering the above, from the viewpoint of improving the dryness after liquid absorption and improving the shape retention of the absorbent article sheet 10, and by extension the absorbent article 1, the ratio W4 / W2 is preferably 0.01 or more and 0.7 or less, more preferably 0.05 or more and 0.5 or less, and even more preferably 0.1 or more and 0.3 or less. If the length W4 is not constant, the length W4 mentioned above refers to the minimum length W4.

[0049] In this embodiment, it is preferable that the dimensions of the liquid film rupture portion 41 are within a predetermined range. Specifically, from the viewpoint of improving dryness after liquid absorption, the length W3 is preferably 5 mm or more, more preferably 10 mm or more, and even more preferably 20 mm or more. Also, from the viewpoint of improving the shape retention of the absorbent article sheet 10 and by extension the absorbent article 1, the length W3 is preferably 400 mm or less, more preferably 300 mm or less, and even more preferably 200 mm or less. If the length W3 is not constant over the entire length of the absorbent article sheet 10 in the longitudinal direction X, it is preferable that the minimum length W3 is within the above range. Also, from the viewpoint of improving dryness after liquid absorption, the length W4 is preferably 0.1 mm or more, more preferably 0.5 mm or more, and even more preferably 1.0 mm or more. Also, from the viewpoint of improving the shape retention of the absorbent article sheet 10 and by extension the absorbent article 1, the length W4 is preferably 5.0 mm or less, more preferably 3.0 mm or less, and even more preferably 2.0 mm or less. If the length W4 is not constant over the entire length Y of the absorbent article sheet 10, it is preferable that the minimum length W4 is within the range described above.

[0050] In the embodiment shown in Figure 4(b), the absorbent article sheet 10 has adhesive 5 formed in stripes along the transverse direction Y. Multiple strips of adhesive 5 are formed at intervals along the longitudinal direction X. On each strip of adhesive 5, a row of liquid film cleavage portions 42 is formed, consisting of liquid film cleavage portions 41 and extending along the transverse direction Y. The direction in which the row of liquid film cleavage portions 42 extends coincides with the direction in which the adhesive 5 extends. In other words, each liquid film cleavage agent 4 constituting the row of liquid film cleavage portions 42 is arranged in a scattered manner along the direction in which the adhesive 5 extends. Furthermore, each liquid film cleavage agent 4 is arranged intermittently along the striped adhesive 5. Both side edges of each liquid film cleavage portion 41 in the row of liquid film cleavage portions 42 are located inward in the longitudinal direction X than both side edges of the adhesive 5. Both ends of the liquid film cleavage portion 41 in the row of liquid film cleavage portions 42 are located inward in the transverse direction Y than both ends of the adhesive 5 in the transverse direction Y. Therefore, the positions of the liquid film cleavage section row 42 and the positions of the adhesive 5 overlap in the thickness direction of the absorbent article sheet 10.

[0051] The absorbent article sheet 10 in the embodiment shown in Figure 4(c) has rows of liquid film cleavage portions 42 extending along the longitudinal direction X, consisting of a plurality of liquid film cleavage portions 41, on both the adhesive 5 and the non-skin side sheet 3. The rows of liquid film cleavage portions 42 are spaced apart along the transverse direction Y of the absorbent article sheet 10 and arranged in four rows along the longitudinal direction X. Specifically, the rows of liquid film cleavage portions 42 are arranged on both sides of the adhesive 5, of which three adhesives 5 are applied linearly along the longitudinal direction X. Rows of liquid film cleavage portions 42 are also arranged on the non-skin side sheet between the adhesives 5 on both sides and the central adhesive 5. No rows of liquid film cleavage portions 42 are arranged on the central adhesive 5. The spacing of the liquid film cleavage portions 41 in the rows of liquid film cleavage portions 42 in the longitudinal direction X is the same for the liquid film cleavage portions 41 applied on the adhesive 5 and the liquid film cleavage portions 41 applied on the non-skin side sheet 3. Thus, in this embodiment, the liquid film cleaving agent 4 is also placed between the non-skin side sheet 3 and the surface sheet 2.

[0052] In the embodiment shown in Figure 5, the adhesive 5 is applied spirally on the non-skin-facing sheet 3. The absorbent article sheet 10 has multiple rows of liquid film cleavage portions 42, each consisting of multiple liquid film cleavage portions 41 and extending along the longitudinal direction X, on the adhesive 5 and the non-skin-facing sheet 3. The rows of liquid film cleavage portions 42 are spaced apart along the transverse direction Y of the absorbent article sheet 10 and arranged in three rows along the longitudinal direction X. Specifically, of the three rows of liquid film cleavage portions 42 arranged in a scattered manner along the longitudinal direction X, the rows of liquid film cleavage portions 42 on both sides are located on the non-skin-facing sheet 3 and not on the adhesive 5. The central row of liquid film cleavage portions 42 is located on the adhesive 5. Thus, in this embodiment, the liquid film cleavage agent 4 is also placed between the non-skin-facing sheet 3 and the surface sheet 2.

[0053] In the embodiments shown in Figures 4(b), 4(c), and 5, the surface sheet 2 and the liquid film cleavage agent 4 are in direct contact, resulting in improved drying properties after liquid absorption due to the liquid film cleavage agent 4. Furthermore, since there is a portion E1 where the adhesive 5 and the surface sheet 2 are directly joined without the liquid film cleavage agent 4, the shape retention of the absorbent article sheet 10, and by extension the absorbent article 1 equipped therewith, is improved.

[0054] In the embodiments shown in Figures 4(c) and 5, that is, embodiments in which the liquid film cleavage agent 4 is placed on both the adhesive 5 and the non-skin side sheet 3, it is preferable that the area of ​​the liquid film cleavage agent 4 placed on the non-skin side sheet 3 in a plan view and the area of ​​the liquid film cleavage agent 4 placed on the adhesive 5 in a plan view have a predetermined relationship. Specifically, when the area of ​​the liquid film cleavage agent 4 placed between the adhesive 5 and the surface sheet 2 in a plan view of the absorbent article 1 is denoted as area A, and the area of ​​the liquid film cleavage agent 4 placed between the surface sheet 2 and the non-skin side sheet 3 is denoted as area B, it is preferable that the ratio of area B to area A, B / A, has a predetermined relationship. Here, "area A" refers to the total area of ​​the liquid film cleavage agent 4 placed between the adhesive 5 and the surface sheet 2 in a square region of the absorbent article sheet 10 with sides of 31.6 mm. "Area B" refers to the total area of ​​the liquid film cleavage agent 4 placed between the surface sheet 2 and the non-skin side sheet 3 in a square region of the absorbent article sheet 10 with sides of 31.6 mm. From the viewpoint of improving the shape retention of the absorbent article sheet 10 and by extension the absorbent article 1, the ratio B / A is preferably 20.0 or less, more preferably 10.0 or less, even more preferably 5.0 or less, even more preferably 3.0 or less, even more preferably 2.0 or less, even more preferably 1.2 or less, even more preferably 1.0 or less, and particularly preferably 0.8 or less. From the viewpoint of making the above-mentioned advantages even more pronounced, a smaller ratio B / A is preferable, but from the viewpoint of improving dryness after liquid absorption, the ratio B / A may be 0.0 or more. Considering the above, from the viewpoint of improving the shape retention of the absorbent article sheet 10 and, by extension, the absorbent article 1, and from the viewpoint of improving the drying properties after liquid absorption, the ratio B / A is preferably 0.0 or more and 20.0 or less, more preferably 10.0 or less, even more preferably 5.0 or less, even more preferably 3.0 or less, even more preferably 2.0 or less, even more preferably 1.2 or less, even more preferably 1.0 or less, and particularly preferably 0.8 or less.

[0055] In this embodiment, it is preferable that the areas A and B of the liquid film cleavage agent 4 are within a predetermined range. Specifically, from the viewpoint of improving dryness, the absorbent article sheet 1000 mm ２ The area A of the liquid film cleavage agent 4 in a plan view per square region (with sides of 31.6 mm) is 10 mm². ２ Preferably, it should be 20 mm or more. ２ It is even more preferable that the amount be greater than or equal to 40 mm ２ It is even more preferable that the above is achieved. Furthermore, from the viewpoint of improving the shape retention of the absorbent article sheet 10 and by extension the absorbent article 1, the absorbent article sheet 1000 mm ２ The area A of the liquid film cleavage agent 4 in a plan view per square region (with sides of 31.6 mm) is 500 mm². ２ Preferably, it is 400 mm ２ It is even more preferable that the following be the case: 300 mm ２ It is even more preferable that the following conditions be met: 200 mm ２ The following is even more preferable: From the viewpoint of improving dryness, a 1000 mm sheet for absorbent articles is preferable. ２ The area B of the liquid film cleavage agent 4 in a plan view per square region (with sides of 31.6 mm) is 500 mm². ２ Preferably, it is 300 mm ２ It is even more preferable that the following be the case: 200 mm ２ It is even more preferable that the following conditions be met: 100 mm ２ The following is even more preferable: From the viewpoint of making the above-mentioned advantages even more pronounced, the smaller the area B, the better, but 10 mm ２ That's fine too.

[0056] The areas A and B of the liquid film cleavage agent 4 in a plan view are measured in the same manner as the area S measurement method described above.

[0057] In the absorbent article sheet 10, for example, as shown in the embodiments in Figures 4(c) and 5, the liquid film cleavage agent 4 may be placed on the adhesive 5 and on the non-skin side sheet 3. From the viewpoint of improving the dryness of the absorbent article sheet 10, and by extension the absorbent article 1, it is particularly preferable that the liquid film cleavage agent 4 is placed only between the adhesive 5 and the surface sheet 2. When the liquid film cleavage agent 4 is placed on the non-skin side sheet 3, the liquid film cleavage agent 4 may unintentionally migrate to the absorbent material 6 side via the non-skin side sheet 3. In contrast, when the liquid film cleavage agent 4 is placed only between the adhesive 5 and the surface sheet 2, the amount of liquid film cleavage agent 4 that can migrate to the absorbent material 6 side is reduced, and the effect of the liquid film cleavage agent 4 is effectively exerted. For this reason, it is preferable that the above-mentioned ratio B / A is as close to 0 as possible, and the area B is 0 mm². ２ The closer to the ideal, the better.

[0058] The absorbent article sheet 10 shown in Figures 4(a) to 4(c) and Figure 5, and the absorbent article 1 equipped therewith, can be manufactured by changing the arrangement of the adhesive 5 or the arrangement of the liquid film cleavage agent 4 in the preferred manufacturing method shown in Figure 3. For example, the absorbent article sheet 10 shown in Figure 5 and the absorbent article 1 equipped therewith can be manufactured by applying the adhesive 5 in a spiral pattern in the first step.

[0059] The absorbent article 1 of the embodiment shown in Figure 6 further has an absorbent body 6 adjacent to the non-skin side sheet 3A, located on the non-skin side of the non-skin side sheet 3A. In other words, in the embodiments described so far, the non-skin side sheet 3 also served as the core wrap sheet, but the absorbent article 1 of this embodiment further has a non-skin side sheet 3A that is separate from the core wrap sheet 3. The non-skin side sheet 3A of this embodiment is typically a sublayer sheet. A sublayer sheet is a sheet-like member in this type of absorbent article, also called a second sheet or intermediate sheet. The sublayer sheet plays various roles, such as improving liquid permeability from the surface sheet 2 to the absorbent body 6, and preventing liquid backflow, which is the phenomenon of excrement absorbed by the absorbent body 6 moving to the skin side of the surface sheet 2. As the non-skin side sheet 3A of this embodiment, a hydrophilic and liquid-permeable sheet can be used. Examples of such sheets include paper, woven fabric, and nonwoven fabric. One of these can be used alone or in combination of two or more.

[0060] In this embodiment, the non-skin side sheet 3A has a rectangular shape that is long in the vertical direction X, and its longitudinal direction is aligned with the vertical direction X, extending along the vertical direction X from the front area through the central area to the rear area of ​​the absorbent article 1. As shown in Figure 6, the adhesive 5 and the non-skin side sheet 3A are in direct contact. The non-skin side sheet 3A and the core wrap sheet 3 are in direct contact. The absorbent article 1 also has a portion E1 where the adhesive 5 and the surface sheet 2 are in direct contact, and a portion E2 where the liquid film cleavage agent 4 is interposed between the adhesive 5 and the surface sheet 2. In this embodiment as well, since the surface sheet 2 and the liquid film cleavage agent 4 are in direct contact, the drying properties after liquid absorption are improved due to the liquid film cleavage agent 4. Furthermore, since there is a portion E1 where the adhesive 5 and the surface sheet 2 are directly joined without the liquid film cleavage agent 4, the shape retention of the absorbent article sheet 10, and by extension the absorbent article 1 equipped therewith, is improved.

[0061] The absorbent article sheet 10 shown in Figure 6 and the absorbent article 1 equipped therewith can be manufactured by, in the preferred manufacturing method shown in Figure 3, by placing an absorbent 6 on a back sheet 7, and then placing a non-skin side sheet 3A, which has an adhesive (not shown) applied to its lower surface, on top of the absorbent 6. Subsequently, by following the first, second, and third steps described above, the absorbent article sheet 10 and the absorbent article 1 equipped therewith of this embodiment can be manufactured.

[0062] In the embodiment shown in Figure 7, the arrangement of the liquid film cleavage agent 4 and the adhesive 5 is reversed in the thickness direction Z of the absorbent article 1 compared to the embodiments described so far. As shown in the figure, the surface sheet 2 and the adhesive 5 are in direct contact. The adhesive 5 and the liquid film cleavage agent 4 are in direct contact. The liquid film cleavage agent 4 and the non-skin side sheet 3 are in direct contact. The absorbent article 1 also has a portion E3 where the adhesive 5 and the non-skin side sheet 3 are in direct contact, and a portion E4 where the liquid film cleavage agent 4 is interposed between the adhesive 5 and the non-skin side sheet 3. Thus, in this embodiment, it is preferable that the liquid film cleavage agent 4 is arranged between the adhesive 5 and the non-skin side sheet 3 so that there is a portion E3 where the adhesive 5 and the non-skin side sheet 3 are directly joined. In this embodiment, the surface sheet 2 and the liquid film cleavage agent 4 are in contact via the adhesive 5. Even in this case, the liquid film cleavage agent 4 is present between the adhesive 5 and the non-skin side sheet 3. Therefore, the drying properties after liquid absorption are improved due to the liquid film cleavage agent 4. Furthermore, since there is a portion E3 where the adhesive 5 and the non-skin side sheet 3 are directly joined without the liquid film cleavage agent 4, the shape retention of the absorbent article sheet 10, and by extension the absorbent article 1 equipped therewith, is improved.

[0063] Similar to the embodiments described above, in this embodiment as well, the liquid film cleavage agent 4 may be placed between the non-skin side sheet 3 and the surface sheet 2. In this case, when the area of ​​the liquid film cleavage agent 4 placed between the adhesive 5 and the non-skin side sheet 3 in a plan view is area A, and the area of ​​the liquid film cleavage agent 4 placed between the surface sheet 2 and the non-skin side sheet 3 is area B, it is preferable that the ratio B / A of area B to area A has a predetermined relationship. From the viewpoint of improving the drying properties after liquid absorption and improving the shape retention of the absorbent article sheet 10, and by extension the absorbent article 1, the ratio B / A can be within the same range as the ratio B / A described above.

[0064] However, from the viewpoint of effectively exerting the effects of the liquid film cleavage agent 4 and improving the dryness of the absorbent article sheet 10, and by extension the absorbent article 1, it is particularly preferable that the liquid film cleavage agent 4 be placed only between the adhesive 5 and the non-skin side sheet 3.

[0065] The absorbent article sheet 10 shown in Figure 7 and the absorbent article 1 equipped therewith are suitably manufactured by changing the member to which the adhesive 5 is applied in the preferred manufacturing method shown in Figure 3. Specifically, the adhesive 5 can be applied to the non-skin side of the surface sheet 2 instead of the skin side of the non-skin side sheet 3. Specifically, first the surface sheet 2 is conveyed by a conveying unit, and in the first step, the adhesive 5 is applied to the non-skin side of the surface sheet 2 using an adhesive application unit. Next, in the second step, the liquid film cleavage agent application unit 81 is used to apply the liquid film cleavage agent 4 onto the adhesive 5. Then, in the third step, the non-skin side sheet 3 is placed on the adhesive 5 of the surface sheet 2, and the surface sheet 2 and the non-skin side sheet 3 are joined together via the adhesive 5 using a joining unit 80A. As a result, the absorbent article sheet 10 obtained has a portion E3 where the adhesive 5 and the non-skin side sheet 3 are in direct contact, and a portion E4 where the liquid film cleavage agent 4 is interposed between the adhesive 5 and the non-skin side sheet 3. The absorbent article sheet 10 obtained in this way and the absorbent article 1 equipped therewith have improved dryness and shape retention after liquid absorption, as described above.

[0066] Next, the liquid film cleavage agent 4 common to the above embodiments will be described. The liquid film cleavage agent of this embodiment preferably satisfies at least one of the following (1) to (4), and more preferably satisfies all of them. (1) The expansion coefficient for a liquid with a surface tension of 50 mN / m is greater than 0 mN / m and less than or equal to 50 mN / m. (2) The water solubility is 0 g or more and less than or equal to 0.025 g. (3) The interfacial tension for a liquid with a surface tension of 50 mN / m is 20 mN / m or less. (4) The melting point is less than 40°C.

[0067] Regarding (1) above, the "expansion coefficient for a liquid with a surface tension of 50 mN / m" of the liquid film cleavage agent 4 is a value obtained from the measurement method described later in an environment with an ambient temperature of 25°C and a relative humidity (RH) of 65%, based on the following formula (A). The "liquid with a surface tension of 50 mN / m" is an expansion coefficient assumed to be excretory material from the human body, such as menstrual blood and urine. The γ in formula (A) below ｗ and γ ｗｏ In this context, "liquid film" refers to the liquid phase of a liquid with a surface tension of 50 mN / m, and includes both the liquid in the state where a film has formed between fibers or on the fiber surface, and the liquid in the state before film formation, and is also simply called liquid. Furthermore, γ in the following formula (A) ｗ and γ ｏ In this specification, "surface tension" refers to the interfacial tension at the interface between the liquid film and the gas phase of compound A (the substance being measured), and is distinct from the interfacial tension between the liquid phase and the liquid film of compound A (the substance being measured). This distinction is also maintained in other descriptions in this specification. S = γ ｗ -γ ｏ -γ ｗｏ ... (A) γ ｗ : Surface tension of liquid film (liquid) γ ｏ : Surface tension of compound A γ ｗｏ : Interfacial tension of compound A with the liquid film

[0068] As can be seen from the above formula (A), the expansion coefficient (S) of the liquid film cleavage agent 4 is the surface tension (γ) of the liquid film cleavage agent 4. ｏ As the size of the liquid film cleavage agent 4 decreases, the interfacial tension (γ) between the liquid film and the liquid film increases. ｗｏThe expansion coefficient increases as the surface tension of the liquid film formed in narrow regions between fibers decreases. When this expansion coefficient exceeds 0 mN / m, the liquid film cleavage agent 4 becomes highly mobile, i.e., highly diffusive, on the surface of the liquid film formed in narrow regions between fibers. From this viewpoint, the expansion coefficient of the liquid film cleavage agent 4 is preferably 3 mN / m or more, more preferably 10 mN / m or more, even more preferably 15 mN / m or more, even more preferably 20 mN / m or more, and particularly preferably 25 mN / m or more. On the other hand, there is no particular upper limit, but from formula (A) above, if a liquid with a surface tension of 50 mN / m is used, the upper limit is 50 mN / m; if a liquid with a surface tension of 60 mN / m is used, the upper limit is 60 mN / m; and if a liquid with a surface tension of 70 mN / m is used, the upper limit is 70 mN / m, and so on, with the surface tension of the liquid forming the liquid film being the upper limit. Therefore, in this embodiment, from the viewpoint of using a liquid with a surface tension of 50 mN / m, the expansion coefficient of the liquid film cleavage agent 4 is 50 mN / m or less. Taking the above into consideration, in this embodiment, from the viewpoint of having high mobility, i.e., diffusion, of the liquid film formed on the surface in the narrow region between fibers, the expansion coefficient of the liquid film cleavage agent 4 for a liquid with a surface tension of 50 mN / m is preferably greater than 0 mN / m and less than or equal to 50 mN / m, preferably 3 mN / m or more, more preferably 10 mN / m or more, even more preferably 15 mN / m or more, even more preferably 20 mN / m or more, and particularly preferably 25 mN / m or more.

[0069] Regarding (2) above, the "water solubility" of the liquid film cleavage agent 4 is the soluble mass of the liquid film cleavage agent 4 per 100 g of deionized water, and is a value measured in an environment with an ambient temperature of 25°C and relative humidity (RH) of 65% based on the measurement method described later. The liquid film cleavage agent 4 has a water solubility of 0 g or more and 0.025 g or less, so that it is not easily soluble in aqueous liquids and forms an interface with the liquid film, resulting in high mobility (diffusivity) on the surface of the liquid film. From a similar viewpoint, the water solubility of the liquid film cleavage agent 4 is preferably 0.0025 g or less, more preferably 0.0015 g or less, and even more preferably less than 0.0001 g. Furthermore, the smaller the water solubility of the liquid film cleavage agent 4, the better, preferably 0 g or more, and from the viewpoint of diffusivity to the liquid film, 1.0 × 10－９ It is practical to set it to g or more. Considering the above, from the viewpoint of being poorly soluble in aqueous liquids, forming an interface with the liquid film, and having high mobility (diffusivity) on the surface of the liquid film, the liquid film cleavage agent 4 has a water solubility of 0 g or more and 0.025 g or less, preferably 0.0025 g or less, more preferably 0.0015 g or less, and even more preferably less than 0.0001 g. It should be noted that the water solubility of the liquid film cleavage agent 4 is also considered to apply to menstrual blood, urine, etc., which are mainly composed of water.

[0070] Regarding (3) above, the fact that the "interfacial tension of the liquid film cleavage agent 4 with respect to a liquid with a surface tension of 50 mN / m" is 20 mN / m or less is determined by the "interfacial tension of compound A with the liquid film" (γ), which is one of the variables that determines the value of the expansion coefficient (S) in formula (A) above. ｗｏ This is equivalent to the value being 20 mN / m or less. ｗｏBy keeping the interfacial tension low, the expansion coefficient of the liquid film cleavage agent 4 is improved, making it easier for the liquid film cleavage agent 4 to migrate from the fiber surface to the vicinity of the center of the liquid film, and thus the liquid film cleavage effect is exhibited. From this viewpoint, the "interfacial tension of the liquid film cleavage agent 4 with respect to a liquid with a surface tension of 50 mN / m" is more preferably 17 mN / m or less, even more preferably 13 mN / m or less, even more preferably 10 mN / m or less, particularly preferably 9 mN / m or less, and especially preferably 1 mN / m or less. On the other hand, the lower limit of the interfacial tension is not particularly limited, and it is sufficient if it is greater than 0 mN / m from the viewpoint of insolubility in the liquid film. Note that if the interfacial tension is 0 mN / m, that is, if the liquid film cleavage agent 4 dissolves in the liquid film, it becomes difficult to form an interface between the liquid film and the liquid film cleavage agent 4, so the above equation (A) does not hold, and expansion of the liquid film cleavage agent 4 does not occur. As can be seen from equation (A) above, the expansion coefficient changes depending on the surface tension of the target liquid. For example, if the surface tension of the target liquid is 72 mN / m, the surface tension of the liquid film slitting agent 4 is 21 mN / m, and the interfacial tension between them is 0.2 mN / m, the expansion coefficient is 50.8 mN / m. Also, if the surface tension of the target liquid is 30 mN / m, the surface tension of the liquid film slitting agent 4 is 21 mN / m, and the interfacial tension between them is 0.2 mN / m, the expansion coefficient is 8.8 mN / m. In either case, the larger the expansion coefficient of the substance, the greater the liquid film slitting effect. In this specification, the values ​​are defined for a surface tension of 50 mN / m, but even if the surface tension is different, the relative magnitudes of the expansion coefficients of each substance do not change. Therefore, even if the surface tension of excrement changes from day to day due to physical condition, substances with larger expansion coefficients will show a superior liquid film slitting effect.

[0071] Regarding (4) above, the "melting point" of the liquid film cleavage agent 4 refers to the temperature at which a solid melts and becomes a liquid. In order to exhibit the liquid film cleavage effect, the liquid film cleavage agent 4 needs to be in a liquid state when it comes into contact with excretions such as menstrual blood and urine. From this point of view, the melting point of the liquid film cleavage agent 4 is less than 40°C, preferably 35°C or lower, more preferably 20°C or lower, even more preferably 10°C or lower, and even more preferably 0°C or lower. Furthermore, the melting point of the liquid film cleavage agent 4 is preferably -220°C or higher, and even more preferably -180°C or higher.

[0072] The above-mentioned "surface tension of liquid film (liquid with a surface tension of 50 mN / m) (γ ｗ ) ", Surface tension of liquid film cleavage agent 4 (γ ｏ ) ``Interfacial tension of liquid film cleavage agent 4 with the liquid film (γ ｗｏ The "water solubility of the liquid film severing agent 4" and the "melting point of the liquid film severing agent 4" are measured by the following method.

[0073] Furthermore, if the object to be measured in the following measurement method is a deposit attached to a fiber (hereinafter also referred to as "fiber deposit"), the fiber is washed with an organic solvent (e.g., hexane, methanol, ethanol, etc.), and the organic solvent after washing (organic solvent containing the object to be measured) is dried to obtain the fiber deposit. The mass of the fiber deposit thus obtained can be used when calculating the content of the fiber treatment agent in a fiber sheet such as a nonwoven fabric (e.g., a nonwoven fabric). The mass of the obtained fiber deposit is used to determine the surface tension (γ ｏ ), interfacial tension (γ ｗｏ If the amount is insufficient for measurement of surface tension (γ), etc., the fiber deposits are identified, and if the fiber deposits are commercially available, the commercially available product is procured, or if they are not commercially available, the amount necessary for measurement is obtained by synthesis, etc. The above "identification of fiber deposits (objects to be measured)" can be performed, for example, by selecting an appropriate column and solvent according to the components of the fiber deposits, fractionating the components of the fiber deposits by high-performance liquid chromatography, and then performing MS measurement, NMR measurement, elemental analysis, etc. on each fraction. If the fiber deposits contain polymer compounds, the identification of the fiber deposits can be made even easier by using methods such as gel permeation chromatography (GPC) in combination. In particular, surface tension (γｏ ) and surface tension (γ ｗｏ Regarding the measurement of the fiber deposit, if the fiber deposit is solid at room temperature and pressure, the fiber deposit is heated to its melting point + 5°C to induce a phase transition to a liquid, and the measurement is performed under those temperature conditions, i.e., on the liquid fiber deposit. Furthermore, if the fiber deposit is attached to a component of an absorbent article (e.g., a surface sheet), the component (hereinafter also referred to as the "measurement target component") is removed from the absorbent article using the following procedure, and then the fiber deposit is measured. That is, the bonding force between the measurement target component and other components in the absorbent article is weakened by spraying a cold spray onto the adhesive, etc., and then the measurement target component is carefully peeled off from the other components and removed from the absorbent article. Unless otherwise specified, this method of removing the measurement target component from the absorbent article is applied as appropriate to the measurements described herein.

[0074] In this specification, "room temperature and atmospheric pressure" refers to an environment with an ambient temperature of 25°C and 1 atmosphere of pressure.

[0075] <Surface tension of liquid film (γ ｗ Measurement Method > The surface tension is measured using the plate method (Wilhelmy method) with a platinum plate in an environment with an ambient temperature of 25°C and a relative humidity (RH) of 65%. The measurement device used is the automatic surface tension meter "CBVP-Z" (product name, manufactured by Kyowa Interface Science Co., Ltd.). The platinum plate used is 99.9% pure and measures 25 mm wide and 10 mm long. The "liquid with a surface tension of 50 mN / m" is a solution prepared by adding polyoxyethylene sorbitan monolaurate (manufactured by Kao Corporation, product name Leodol Super TW-L120), a nonionic surfactant, to deionized water using the measurement method described above, and adjusting the surface tension to 50 ± 1 mN / m.

[0076] <Surface tension of liquid film cleavage agent 4 (γ ｏ ) Measurement method > Surface tension of liquid film (γ ｗSimilar to the measurement of ( ), the measurement is performed using the plate method with the same apparatus in an environment with an ambient temperature of 25°C and relative humidity (RH) of 65%. If the object to be measured (fiber deposits) is solid at room temperature and pressure, as described above, it is heated to its melting point + 5°C to induce a phase transition to liquid, and the measurement is performed under those temperature conditions.

[0077] <Interfacial tension between the liquid film cleavage agent 4 and the liquid film (γ ｗｏ Measurement Method > Measurement can be performed using the pendant drop method in an environment with an ambient temperature of 25°C and a relative humidity (RH) of 65%. An automatic interfacial viscoelasticity analyzer (TECLIS-ITCONCEPT, product name THE TRACKER, or KRUSS, product name DSA25S) can be used as the measuring device. In the pendant drop method, as soon as the drop is formed, the adsorption of nonionic surfactants contained in a liquid with a surface tension of 50 mN / m begins, and the interfacial tension decreases over time. Therefore, the interfacial tension at the time the drop is formed (0 seconds) is read. If the object to be measured (fiber deposit) is solid at room temperature and pressure, as described above, it should be heated to its melting point + 5°C to induce a phase transition to a liquid, and the measurement should be performed under those temperature conditions. Furthermore, when measuring interfacial tension, if the density difference between the object being measured and a liquid with a surface tension of 50 mN / m is relatively small, or if the viscosity of the object being measured is extremely high, or if the interfacial tension value is below the measurement limit of the pendant drop method, measuring interfacial tension using the pendant drop method may be difficult. In such cases, measurement is possible by using the spinning drop method in an environment with an ambient temperature of 25°C and a relative humidity (RH) of 65%. A spinning drop interfacial tension meter (manufactured by KRUSS, product name SITE100) can be used as the measuring device for this purpose. In this measurement as well, the interfacial tension is read when the shape of the drop has stabilized, and if the object being measured (fiber deposit) is solid at room temperature and pressure, it is heated to its melting point + 5°C to induce a phase transition to a liquid, and the measurement is performed under those temperature conditions. If interfacial tension can be measured with both measuring devices, the smaller interfacial tension value is adopted as the measurement result.

[0078] <Method for measuring the water solubility of liquid film cleavage agent 4> In an environment with an ambient temperature of 25°C and relative humidity (RH) of 65%, 100g of deionized water is stirred with a stirrer, and the substance to be measured (fiber deposits) is gradually dissolved. The degree of dissolution is observed visually, and the amount of the substance dissolved when it can no longer be dissolved, that is, when any one of the following can be visually confirmed: suspension, precipitation, precipitate, or turbidity, is defined as the water solubility. Specifically, the substance to be measured is added in increments of 0.0001g and measured. If it is observed that not even 0.0001g dissolves, it is defined as "less than 0.0001g", and if it is observed that 0.0001g dissolves and 0.0002g does not dissolve, it is defined as "0.0001g". Note that if the substance to be measured is a surfactant, "dissolution" means both monodisperse dissolution and micelle dispersion dissolution, and the amount of dissolution when suspension, precipitation, precipitate, or turbidity is observed is defined as the water solubility.

[0079] <Method for measuring the melting point of the liquid film cleavage agent 4> Using a differential scanning calorimeter, the temperature of the object to be measured (fiber-attached material) is raised from -20 to 200°C at a rate of 20°C / min, and the melting peak temperature is measured. This measured value is taken as the melting point of the object to be measured. In measuring this melting peak temperature, the weight of the object to be measured is 2 mg. As a differential scanning calorimeter, for example, Hitachi High-Tech Corporation's "DSC7000X" can be used.

[0080] The liquid film cleavage agent 4 that satisfies conditions (1)-(4) above spreads on the surface of the liquid film without dissolving and can push aside the liquid film layer from near the center of the liquid film. This destabilizes the liquid film and causes it to cleave. As a result, the absorbent article sheet 10 on which the liquid film cleavage agent 4 is placed, and the absorbent article 1 equipped therewith, exhibit improved dryness after liquid absorption.

[0081] In order to more reliably exhibit the liquid film cleavage effect, the lower the surface tension of the liquid film cleavage agent 4, the better. From this viewpoint, the surface tension of the liquid film cleavage agent 4 is preferably 40 mN / m or less, more preferably 35 mN / m or less, even more preferably 30 mN / m or less, and even more preferably 25 mN / m or less. On the other hand, from the viewpoint of the durability of the liquid film cleavage agent 4, a surface tension of 1 mN / m or more is practical, preferably 5 mN / m or more, more preferably 10 mN / m or more, and even more preferably 15 mN / m or more.

[0082] Such liquid film cleavage agents 4 can be classified into, for example, silicone compounds and non-silicone compounds. In this embodiment, one or more selected from the group consisting of silicone compounds and non-silicone compounds can be used as the liquid film cleavage agent 4. Specific examples of the silicone compounds include, for example, dimethicone, dimethiconol, and cyclomethicone; amino-modified silicones; and polyether-modified silicones. Specific examples of the non-silicone compounds include, for example, polyether compounds selected from polyalkylene glycols and polyoxyalkylene alkyl ethers; hydrocarbon compounds having 5 to 18 carbon atoms; saturated fatty acids or derivatives thereof having 9 or fewer carbon atoms; and unsaturated fatty acids or derivatives thereof having 22 or fewer carbon atoms. As the liquid film cleavage agent 4, the liquid film cleavage agent described in

[0038] to

[0054] and

[0057] to

[0109] of Japanese Patent Application Publication No. 2017-214694 can also be used.

[0083] Although the present invention has been described above based on its preferred embodiments, the present invention is not limited to the above embodiments. For example, in the embodiments shown in Figures 1, 6, and 7, the surface sheet 2 is flat, but instead, a surface sheet 2 with an uneven shape may be used.

[0084] With regard to the embodiments of the present invention described above, the present invention further discloses the following absorbent articles and apparatus for manufacturing the same, as well as sheets for absorbent articles and methods for manufacturing the same.

[0085] <1> An absorbent article comprising a surface sheet, a non-skin side sheet located on the non-skin side of the surface sheet, and a liquid film cleavage agent disposed between the two sheets, wherein the surface sheet and the non-skin side sheet are joined by an adhesive, and the liquid film cleavage agent is disposed between the adhesive and the surface sheet or the non-skin side sheet such that it has a portion where the adhesive and the surface sheet or the non-skin side sheet are directly joined.

[0086] <2> The absorbent article according to <1>, wherein the adhesive is applied in a stripe or spiral pattern. <3> The absorbent article according to <2>, wherein the liquid film cleavage agent is intermittently arranged along the adhesive, and the distance between adjacent liquid film cleavage agents is preferably 3 mm to 30 mm, more preferably 4 mm to 20 mm, and even more preferably 5 mm to 15 mm. <4> The absorbent article according to any one of <1> to <3>, wherein the adhesive is applied in a stripe pattern, and the liquid film cleavage agent is arranged linearly or in a scattered pattern along the direction in which the adhesive extends. <5> The absorbent article according to <4>, wherein, when the absorbent article is worn, it has a longitudinal direction that coincides with the front-to-back direction of the wearer and a transverse direction perpendicular to the longitudinal direction, and the length of the stripe-shaped adhesive in the transverse direction is preferably 0.5 mm to 10 mm, more preferably 1 mm to 7 mm, and even more preferably 1.5 mm to 5 mm. <6> The absorbent article according to <5>, wherein, when the absorbent article is worn, it has a longitudinal direction that coincides with the front-to-back direction of the wearer and a transverse direction perpendicular to the longitudinal direction, the adhesive is arranged at intervals in the transverse direction, and the distance between adjacent adhesives in the transverse direction is preferably 3 mm or more and 30 mm or less, more preferably 5 mm or more and 25 mm or less, and even more preferably 8 mm or more and 20 mm or less.

[0087] <7> The absorbent article according to any one of <1> to <6>, wherein, when the absorbent article is worn, it has a longitudinal direction that coincides with the front-to-back direction of the wearer and a transverse direction perpendicular to the longitudinal direction, and the ratio of the transverse length of the liquid film cleavage agent to the transverse length of the adhesive (transverse length of the liquid film cleavage agent / transverse length of the adhesive) is preferably 0.01 or more and 0.7 or less, more preferably 0.05 or more and 0.5 or less, and even more preferably 0.1 or more and 0.3 or less. <8> The absorbent article according to any one of <1> to <7>, wherein the liquid film cleavage agent is also disposed between the non-skin sheet and the surface sheet, and the ratio of the area B of the liquid film cleavage agent disposed between the surface sheet and the non-skin sheet to the area A of the liquid film cleavage agent disposed between the adhesive and the surface sheet or the non-skin sheet is preferably 0.0 to 20.0, more preferably 10.0 or less, even more preferably 5.0 or less, even more preferably 3.0 or less, even more preferably 2.0 or less, even more preferably 1.2 or less, even more preferably 1.0 or less, and particularly preferably 0.8 or less. <9> The absorbent article according to any one of <1> to <8>, wherein the liquid film cleavage agent is disposed only between the adhesive and the surface sheet or the non-skin sheet. <10> The absorbent article according to any one of <1> to <9>, wherein the non-skin sheet is made of a liquid-permeable nonwoven fabric or paper. <11> The absorbent article according to any one of <1> to <10>, further comprising an absorbent body comprising an absorbent core and the non-skin side sheet covering the absorbent core.

[0088] <12> The absorbent article according to any one of <1> to <10>, further comprising an absorbent adjacent to the non-skin sheet at a position on the non-skin side of the non-skin sheet. <13> The liquid film cleavage agent is preferably 0.1 g / m² relative to the area of ​​the absorbent article. ２ 10.0g / m or more ２ More preferably, 0.2 g / m ２ 7.0g / m or more ２ More preferably, 0.3 g / m ２ 5.0g / m or more ２Next, more preferably 0.8 g / m ２ or more and 3.0 g / m ２ or less, the absorbent article according to any one of <1> to <12> above. <14> The absorbent article includes an absorbent article sheet having the surface sheet, the non-skin side sheet, and the liquid film splitting agent disposed between the surface sheet and the non-skin side sheet, and the liquid film splitting agent is disposed in a droplet shape at a predetermined position of the absorbent article sheet to form a liquid film splitting site, and the amount of the liquid film splitting agent included per one of the liquid film splitting sites is preferably 0.01 mg or more and 2.0 mg or less, more preferably 0.03 mg or more and 1.0 mg or less, still more preferably 0.05 mg or more and 0.5 mg or less, and even more preferably 0.05 mg or more and 0.2 mg or less, the absorbent article according to any one of <1> to <13> above. <15> The absorbent article includes an absorbent article sheet having the surface sheet, the non-skin side sheet, and the liquid film splitting agent disposed between the surface sheet and the non-skin side sheet, and the total area of the liquid film splitting agent per 1000 mm ２ of the absorbent article sheet in a plan view is preferably 3 mm ２ or more and 300 mm ２ or less, more preferably 10 mm ２ or more and 200 mm ２ or less, still more preferably 50 mm ２ or more and 150 mm ２ or less, the absorbent article according to any one of <1> to <14> above. <16> The liquid film splitting agent has a spreading coefficient with respect to a liquid having a surface tension of 50 mN / m greater than 0 mN / m and less than or equal to 50 mN / m, preferably 3 mN / m or more, more preferably 10 mN / m or more, still more preferably 15 mN / m or more, even more preferably 20 mN / m or more, and particularly preferably 25 mN / m or more, the absorbent article according to any one of <1> to <15> above.

[0089] <17> The absorbent article according to any one of <1> to <16> above, wherein the liquid film cleavage agent has a water solubility of 0 g or more and 0.025 g or less, preferably 0.0025 g or less, more preferably 0.0015 g or less, and even more preferably less than 0.0001 g. <18> The absorbent article according to any one of <1> to <17> above, wherein the liquid film cleavage agent has an interfacial tension of 20 mN / m or less, more preferably 17 mN / m or less, even more preferably 13 mN / m or less, even more preferably 10 mN / m or less, particularly preferably 9 mN / m or less, and especially preferably 1 mN / m or less, with respect to a liquid with a surface tension of 50 mN / m. <19> The absorbent article according to any one of <1> to <18> above, wherein the liquid film cleavage agent has a melting point of less than 40°C, preferably 35°C or less, more preferably 20°C or less, even more preferably 10°C or less, and even more preferably 0°C or less. <20> The absorbent article according to any one of <1> to <19>, wherein the liquid film cleavage agent is one or more selected from the group consisting of silicone compounds and non-silicone compounds. <21> An absorbent article sheet having a surface sheet, a non-skin sheet located on the non-skin side of the surface sheet, and a liquid film cleavage agent disposed between the two sheets, wherein the surface sheet and the non-skin sheet are joined by an adhesive, and the liquid film cleavage agent is disposed between the adhesive and the surface sheet or the non-skin sheet such that it has a portion where the adhesive and the surface sheet or the non-skin sheet are directly joined.

[0090] <22> A method for manufacturing an absorbent sheet for an absorbent article, comprising: a first step of applying the adhesive to the skin side of the non-skin sheet or the non-skin side of the surface sheet; a second step of applying a liquid film cleavage agent on the adhesive; and a third step of arranging the surface sheet or the non-skin sheet on the adhesive and joining the surface sheet and the non-skin sheet via the adhesive, wherein in the second step, the liquid film cleavage agent is applied on the adhesive such that there are portions where the adhesive and the surface sheet or the non-skin sheet are directly joined. <23> The manufacturing method according to <22>, wherein in the first step, the adhesive is applied in a stripe or spiral pattern. <24> The manufacturing method according to <22> or <23>, wherein in the second step, the liquid film cleavage agent is applied by an inkjet printing method. <25> An apparatus for manufacturing an absorbent article comprising a surface sheet and a non-skin side sheet joined together by an adhesive, the apparatus comprising: a conveying section for conveying the non-skin side sheet; an adhesive application section for applying adhesive to the skin side of the conveyed non-skin side sheet; a liquid film cleavage agent application section for intermittently applying a liquid film cleavage agent to the adhesive on the non-skin side sheet using an inkjet nozzle; and a joining section for overlapping and joining the surface sheet on the non-skin side sheet to which the liquid film cleavage agent has been applied. <26> A manufacturing apparatus for an absorbent article comprising a surface sheet and a non-skin side sheet joined together by an adhesive, the apparatus comprising: a conveying section for conveying the surface sheet; an adhesive application section for applying adhesive to the non-skin side of the conveyed surface sheet; a liquid film cleavage agent application section for intermittently applying a liquid film cleavage agent to the adhesive on the surface sheet using an inkjet nozzle; and a joining section for overlapping and joining the non-skin side sheet onto the surface sheet that has been applied with the adhesive.

[0091] The present invention will be described in more detail below with reference to examples. However, the scope of the present invention is not limited to these examples. Unless otherwise specified, "%" means "mass%".

[0092] [Example 1] A sanitary napkin having the structure shown in Figures 1 and 2 was manufactured. A liquid film cleavage agent was applied to a single stripe-shaped adhesive so that a row of liquid film cleavage points formed a linear sequence of dots along the longitudinal direction of the sanitary napkin. The absorbent material, the hot-melt adhesive, and the surface sheet were each applied at a density of 0.032 kg / cm². ２ The materials were bonded together under the specified load. Details of the liquid film cleavage agent are as follows: <Liquid Film Cleavage Agent> ・Type: POE(3) modified dimethyl silicone ・Expansion coefficient for liquids with a surface tension of 50 mN / m: 28.8 mN / m ・Water solubility: Less than 0.0001 g ・Interfacial tension for liquids with a surface tension of 50 mN / m: 0.2 mN / m ・Melting point: Less than -20°C ・Surface tension: 21 mN / m

[0093] [Example 2] A sanitary napkin having the structure shown in Figure 8 was manufactured. A liquid film cleavage agent was applied to the striped adhesives on both sides, so that each side had a row of liquid film cleavage points forming a linear sequence of dots along the longitudinal direction of the sanitary napkin. In addition, a liquid film cleavage agent was applied to the absorbent material between the adhesives on both sides and the central adhesive, so that each side had a row of liquid film cleavage points forming a linear sequence of dots along the longitudinal direction. The absorbent material, the hot melt adhesive, and the surface sheet were combined at a density of 0.032 kg / cm². ２ The two parts were bonded together under a load. The same liquid film cleavage agent used in Example 1 was used.

[0094] [Comparative Example 1] In Example 1, instead of placing the liquid film cleavage agent between the surface sheet and the adhesive, the liquid film cleavage agent was placed on the skin-facing side of the surface sheet. A sanitary napkin was manufactured in the same manner as in Example 1, except for this difference.

[0095] [Comparative Example 2] In Example 1, a liquid film cleavage agent was placed on the adhesive in the same length and width as the adhesive. Otherwise, a sanitary napkin was manufactured in the same manner as in Example 1. In the sanitary napkin of this comparative example, the adhesive and the surface sheet are not in direct contact.

[0096] [Comparative Example 3] In Example 1, no liquid film cleavage agent was placed between the surface sheet and the adhesive. Furthermore, two rows of liquid film cleavage agents, consisting of dots, were placed on the non-skin side sheet between adjacent adhesives. A sanitary napkin was manufactured in the same manner as in Example 1, except for these differences.

[0097] [Comparative Example 4] In Example 1, the liquid film cleavage agent was not included. Otherwise, sanitary napkins were manufactured in the same manner as in Example 1.

[0098] [Evaluation] For the sanitary napkins of the examples and comparative examples, the amount of liquid film cleavage agent, the amount of liquid film cleavage agent contained in each liquid film cleavage site, and the areas S, A, and B were measured according to the method described above. Furthermore, the lengths W1, W2, W3, and W4, and the distances D1, D2, and D3 were measured. In addition, for the sanitary napkins of the examples and comparative examples, the amount of remaining liquid, the transfer rate of the liquid film cleavage agent, and the adhesive strength were evaluated according to the method described below. These results are shown in Table 1 below.

[0099] [Amount of remaining liquid] In the center of the sanitary napkins of the examples and comparative examples, the short axis radius was 1.12 cm, the long axis radius was 2.50 cm, and the area was 8.8 cm². ２ An elliptical acrylic cylinder was placed so that the product's longitudinal direction was its long axis. 3.0 g of sterile defibrillated horse blood (sterile defibrillated horse blood manufactured by Japan Biomaterials Center Co., Ltd., adjusted to 24.0 cP) equivalent to menstrual blood was injected into the cylinder in one go. The viscosity of the horse blood used was adjusted using a TVB10 viscometer manufactured by Toki Sangyo under the conditions of rotor No. 20, rotor M1, and 12 rpm. When horse blood is left to stand, the high-viscosity portion (red blood cells, etc.) settles, and the low-viscosity portion (plasma) remains as supernatant. The mixing ratio of these portions was adjusted to 24.0 cP. One minute after injection, the horse blood adhering to the inside of the cylinder was absorbed with tissue, the cylinder was removed, and 13 g / m² of basis weight material was placed in the center of the product. ２A rectangular weight weighing 125 g with a base measuring 3.0 cm on the short side and 10.5 cm on the long side was placed on top of absorbent paper (16 sheets of commercially available tissue paper stacked together), with the long side facing the product's longitudinal direction, and pressure was applied for 1 minute. After 1 minute, the weight and absorbent paper were removed. After 2 minutes, the cylinder was placed in the center of the sanitary napkin that had undergone the previous series of operations, and the same operation (after injecting 3.0 g of horse blood, placing new absorbent paper and the 125 g weight on top and applying pressure for 1 minute, then removing the weight and absorbent paper after 1 minute) was repeated. The amount of horse blood adhering to the absorbent paper used in the second operation was calculated from the difference in weight of the absorbent paper before and after absorption, and this was defined as the amount of residual liquid. The above operation was performed three times, and the average value of the three results was defined as the amount of residual liquid (mg) of the nonwoven fabric. The smaller the value of the amount of residual liquid, the better the sanitary napkin's dryness and the higher its rating.

[0100] [Transfer rate of liquid film cleavage agent] A PET film (7.5 cm in the longitudinal direction x 5 cm in the transverse direction, KOKUYO OHP sheet) was placed on the skin side of the surface sheet of the sanitary napkins in the examples and comparative examples, and the transfer rate was 0.027 kg / cm². ２ A load was applied for 10 seconds. After unloading, the PET film was peeled off the surface sheet, and the amount of liquid film slitting agent transferred was measured based on the mass of the PET film before and after application. The amount of liquid film slitting agent coated in the overlapping area between the surface sheet and the PET film was also calculated. The transfer rate of the liquid film slitting agent was calculated based on the following formula. The evaluation was performed three times, and the average was taken as the transfer rate of the liquid film slitting agent for the sheet. Transfer rate of liquid film slitting agent (%) = Amount of liquid film slitting agent transferred / Amount of liquid film slitting agent coated × 100

[0101] [Adhesive Strength] A 3 cm wide clip was attached to a digital force gauge. The edge of the surface sheet of the sanitary napkins in the examples and comparative examples was grasped with the clip, and with the absorbent material of the sanitary napkin fixed in place, the digital force gauge was moved upward relative to the sanitary napkin, and the surface sheet was peeled 5 cm from the absorbent material in the longitudinal direction. The maximum strength at which 5 cm was peeled was defined as the adhesive strength (N). The evaluation was performed three times, and the average was defined as the adhesive strength.

[0102]

[0103] As is clear from the results shown in Table 1, the sanitary napkin of Example 1 showed higher evaluation results for liquid residue amount, transfer rate of the liquid film cleavage agent, and adhesive strength compared to the sanitary napkins of Comparative Examples 1 to 4. The sanitary napkin of Example 2 showed a transfer rate and adhesive strength equivalent to that of the sanitary napkin of Example 1, but the evaluation result for liquid residue amount was lower. This is thought to be because the liquid film cleavage agent used is water-repellent, which partially suppressed liquid transfer from the surface sheet to the absorbent.

[0104] According to the present invention, it is possible to provide absorbent articles, absorbent article sheets, and methods for manufacturing the same, which have improved dryness after liquid absorption while suppressing equipment contamination caused by liquid film cleavage agents.

Claims

1. An absorbent article comprising a surface sheet, a non-skin sheet located on the non-skin side of the surface sheet, and a liquid film cleavage agent disposed between the two sheets, wherein the surface sheet and the non-skin sheet are joined by an adhesive, and the liquid film cleavage agent is disposed between the adhesive and the surface sheet or the non-skin sheet such that it has a portion where the adhesive and the surface sheet or the non-skin sheet are directly joined.

2. The absorbent article according to claim 1, wherein the adhesive is applied in a stripe or spiral pattern.

3. The absorbent article according to claim 2, wherein the liquid film cleavage agent is intermittently arranged along the adhesive, and the distance between adjacent liquid film cleavage agents is 3 mm or more and 30 mm or less.

4. The absorbent article according to claim 1, wherein the adhesive is applied in a stripe pattern, and the liquid film cleavage agent is arranged in a linear or scattered pattern along the direction in which the adhesive extends.

5. The absorbent article according to claim 1, wherein the liquid film cleavage agent is also disposed between the non-skin sheet and the surface sheet, and the ratio of the area B of the liquid film cleavage agent disposed between the surface sheet and the non-skin sheet to the area A of the liquid film cleavage agent disposed between the adhesive and the surface sheet or the non-skin sheet is 0.0 or more and 20.0 or less.

6. The absorbent article according to claim 1, wherein the liquid film cleavage agent is disposed only between the adhesive and the surface sheet or the non-skin side sheet.

7. The absorbent article according to claim 1, wherein the non-skin-facing sheet is made of a liquid-permeable nonwoven fabric or paper.

8. The absorbent article according to claim 1, further comprising an absorbent core and the non-skin side sheet covering the absorbent core.

9. The absorbent article according to claim 1, further comprising an absorbent adjacent to the non-skin sheet at a position closer to the non-skin sheet than the non-skin sheet.

10. The liquid film cleavage agent is 0.1 g / m² relative to the area of ​​the absorbent article. ２ 10.0g / m or more ２ The absorbent article according to claim 1, distributed in the following quantities.

11. A sheet for absorbent articles, comprising a surface sheet, a non-skin side sheet located on the non-skin side of the surface sheet, and a liquid film cleavage agent disposed between the two sheets, wherein the surface sheet and the non-skin side sheet are joined by an adhesive, and the liquid film cleavage agent is disposed between the adhesive and the surface sheet or the non-skin side sheet such that it has portions where the adhesive and the surface sheet or the non-skin side sheet are directly joined.

12. A method for manufacturing an absorbent sheet for an absorbent article, comprising: a first step of applying the adhesive to the skin side of the non-skin sheet or the non-skin side of the surface sheet; a second step of applying a liquid film cleavage agent on the adhesive; and a third step of arranging the surface sheet or the non-skin sheet on the adhesive and joining the surface sheet and the non-skin sheet via the adhesive, wherein in the second step, the liquid film cleavage agent is applied on the adhesive such that there is a portion where the adhesive and the surface sheet or the non-skin sheet are directly joined.

13. The manufacturing method according to claim 12, wherein in the first step, the adhesive is applied in a stripe or spiral pattern.

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