JP7286533B2 - absorbent article - Google Patents

Description

The present invention relates to absorbent articles containing vegetable oil.

US Pat. No. 5,300,000 discloses an absorbent article containing vegetable oil. A vegetable oil is selected as the oil composition in the topsheet coating. Patent Document 1 mentions almond oil, sunflower oil, and rapeseed oil in addition to olive oil as vegetable oils.

Japanese Patent Publication No. 2019-517334

In Patent Literature 1, a functional sheet containing vegetable oil is bonded to another constituent member that comes into contact with the functional sheet via an adhesive or the like. When vegetable oil is applied to the functional sheet, the adhesive comes into contact with the vegetable oil of the functional sheet, making it difficult to secure the adhesive force between the functional sheet and other constituent members.

Accordingly, the present invention has been made to solve the above-described problems, and provides an absorbent article having a functional sheet to which vegetable oil is applied, which ensures adhesive strength between the functional sheet and other constituent members. To provide an absorbent article which is easy to wash.

An absorbent article according to one aspect has an absorbent core and a functional sheet disposed outside the absorbent core in the thickness direction and to which vegetable oil is applied, and the thickness of the functional sheet The basis weight of the vegetable oil on the outer surface in the direction is higher than the basis weight of the vegetable oil on the inner surface in the thickness direction of the functional sheet.

FIG. 1 is a plan view of an absorbent article according to an embodiment in an unfolded state, viewed from the skin surface side. FIG. 2 is a plan view of the absorbent article according to the embodiment in the unfolded state, viewed from the non-skin surface side. FIG. 3 is a schematic cross-sectional view along line AA shown in FIG. 4 is an enlarged cross-sectional view of a portion B shown in FIG. 3. FIG. FIG. 5 is an enlarged schematic diagram showing fibers constituting a top sheet as a functional sheet. FIG. 6 is an enlarged cross-sectional photograph of the functional sheet.

(1) Overview of Embodiments At least the following matters will become clear from the description of this specification and the accompanying drawings.
An absorbent article according to one aspect has an absorbent core and a functional sheet disposed outside the absorbent core in the thickness direction and to which vegetable oil is applied, and the thickness of the functional sheet The basis weight of the vegetable oil on the outer surface in the direction is higher than the basis weight of the vegetable oil on the inner surface in the thickness direction of the functional sheet. The outer surface of the functional sheet is located outside the inner surface of the functional sheet in the thickness direction, is close to the outer surface of the absorbent article, and has a high basis weight of vegetable oil. Therefore, the effects of vegetable oil can be imparted to the wearer or the like. The inner surface of the functional sheet comes into contact with other constituent members located inside the functional sheet. At this time, since the basis weight of the inner surface of the functional sheet is relatively low, problems such as difficulty in bonding with the adhesive due to the arrangement of the vegetable oil can be suppressed.

According to a preferred aspect, an elastic member may be bonded to the inner surface of the functional sheet, and the vegetable oil may be provided in a region overlapping with the elastic member. Since the basis weight of the vegetable oil on the inner surface of the functional sheet is low, it is possible to maintain the bonding state of the elastic member to the functional sheet.

According to a preferred aspect, the functional sheet is a nonwoven fabric having fibers, and the functional sheet includes an outer region extending inwardly from the outer surface of the functional sheet and an outer region extending outward from the inner surface of the functional sheet. and an inner region extending into the inner region, wherein the average fiber diameter of the outer region may be smaller than the average fiber diameter of the inner region. Compared to the outer region, the inner region has a relatively large average fiber diameter and tends to have large voids between fibers. The adhesive in contact with the inner region can easily enter the gaps between the fibers, making it easier to secure the adhesive strength of the adhesive.

According to one preferred aspect, the thickness of the inner region may be greater than the thickness of the outer region. By increasing the thickness of the inner region where it is easy to secure the voids between the fibers, the drawing property of the adhesive is enhanced and the bodily fluid drawn into the inner region is easily retained, thereby improving the drawing property of the body fluid.

According to a preferred aspect, the outer region may have an average fiber diameter of 1.7 dtex or less, and the inner region may have an average fiber diameter of 3.3 dtex or more. Since the average fiber diameter of the inner region is relatively large, it is easy to secure voids between fibers. In addition, since the average fiber diameter of the outer region is relatively small, the gaps between fibers tend to be small. Therefore, body fluids and adhesives that have entered the voids between fibers in the inner region are less likely to migrate to the outer region. Therefore, it is possible to retain the adhesive in the inner region to ensure adhesive strength, retain body fluid in the inner region, and suppress rewetting of the outer surface of the absorbent article.

The density of the vegetable oil in the outer region may be higher than the density of the vegetable oil in the inner region. The outer region of the functional sheet is located outside the inner region in the thickness direction, is close to the outer surface of the absorbent article, and has a high density of vegetable oil. Therefore, the effects of vegetable oil can be imparted to the wearer or the like. The inner region contacts other constituent members located inside the functional sheet. At this time, since the density of the inner region is relatively low, problems such as difficulty in bonding with the adhesive due to the placement of the vegetable oil can be suppressed.

According to a preferred aspect, the functional sheet is arranged on the outer surface of the absorbent article, and the fibers are composed of a fiber main body and a fiber treatment agent that covers the surface of the fiber main body and has hydrophilicity. and an oil layer, and the vegetable oil may be contained in the oil layer. Since the functional sheet is arranged on the outer surface of the absorbent article, it is easy for the wearer or the wearing assistant (hereinafter referred to as the wearer, etc.) to come into direct contact with the functional sheet. In addition, since the oil layer covers the surface of the fibers, it is easy to distribute the vegetable oil evenly over the entire functional sheet, and when the wearer touches the functional sheet, the vegetable oil can be easily transferred to the wearer. can. In addition, since the oil layer is hydrophilic, it draws in body fluids such as urine and sweat, thereby improving the feel of the outer surface of the functional sheet.

The density of fibers in the inner region may be lower than the density of fibers in the outer region. Since the density of the fibers in the inner region is lower than the density of the fibers in the outer region, it is easy to secure voids between the fibers. The adhesive in contact with the inner region can easily enter the gaps between the fibers, making it easier to secure the adhesive strength of the adhesive. In addition, the functional sheet can easily hold bodily fluids that have been drawn into the functional sheet, and the ability to draw in bodily fluids can also be improved.

According to a preferred aspect, a sheet pressing section may be provided in which the functional sheet is compressed at least in the thickness direction, and at least part of the vegetable oil may be provided in the sheet pressing section. When forming the sheet pressing portion, generally, the functional sheet is pressed by pressing the convex portion corresponding to the sheet pressing portion against the functional sheet. At this time, the protrusions are in close contact with the functional sheet and may be difficult to separate from the functional sheet. However, since the vegetable oil is arranged in the portion forming the sheet pressing portion, the convex portion pressed against the sheet pressing portion tends to separate from the sheet pressing portion. Therefore, the convex portion and the sheet compressing portion can be smoothly separated from each other without providing the convex portion with a surface treatment for facilitating the separation of the convex portion and the sheet pressing portion, thereby improving manufacturing efficiency.

According to a preferred embodiment, the vegetable oil may have an oleic acid content of 55% or more and 83% or less. A vegetable oil having an oleic acid content of 55% or more and 83% or less is relatively difficult to be oxidized and deteriorated among vegetable oils. By suppressing the deterioration of the vegetable oil, the deterioration of the color and fragrance due to oxidation is suppressed, and the wearer or the like is less likely to feel uncomfortable with the fragrance, and can continue to use the oil with peace of mind.

(2) Absorbent Articles According to Embodiments Absorbent articles according to embodiments will be described below with reference to the drawings. In addition, in the following description of the drawings, the same or similar reference numerals are given to the same or similar parts. However, it should be noted that the drawings are schematic, and the ratio of each dimension is different from the actual one. Therefore, specific dimensions and the like should be determined with reference to the following description. In addition, portions having different dimensional relationships and ratios may also be included between the drawings.

The absorbent article according to the present invention is an absorbent article capable of absorbing a wearer's bodily fluids. The wearer can be exemplified by infants and the elderly. The absorbent article may be a disposable diaper and an incontinence pad that absorb urine, a sanitary napkin that absorbs menstrual blood, or a vaginal discharge sheet that absorbs vaginal discharge. The disposable diaper may be a pants-type diaper or a tape-type diaper. The absorbent article according to the embodiment is a tape-type disposable diaper. FIG. 1 is a schematic plan view of an absorbent article 1 according to an embodiment in a developed state as seen from the skin surface side. FIG. 2 is a schematic plan view of the absorbent article 1 according to the embodiment in a developed state as viewed from the non-skin surface side. The schematic plan views shown in FIGS. 1 and 2 show a stretched state in which the absorbent article 1 is stretched to a state where no wrinkles are formed. FIG. 3 is a schematic cross-sectional view along line AA shown in FIG. 4 is an enlarged cross-sectional view of a portion C shown in FIG. 3. FIG. In the schematic cross-sectional view, each member may be spaced apart in the thickness direction T for convenience of explanation, but they are in contact with each other in the thickness direction T in an actual product.

The absorbent article 1 has a front-rear direction L and a width direction W perpendicular to each other. The front-rear direction L is defined by the direction extending to the front side of the body and the rear side of the body. In other words, the front-rear direction L is a direction extending front-rear in the unfolded absorbent article 1 . In addition, the absorbent article 1 has a thickness direction T in which both the front-rear direction L and the width direction W are perpendicular to each other. The thickness direction T extends to a skin side T1 facing the wearer and a non-skin side T2 opposite to the skin side T1. The absorbent article 1 has a front waist region S1, a back waist region S2, and a crotch region S3. The front waist region S1 is a region facing the front waist (abdomen) of the wearer. The back waist region S2 is a region facing the back waist (back) of the wearer. The crotch region S3 is located at the crotch of the wearer, is a region arranged between the front waist region S1 and the back waist region S2, and may be a region in which the leg openings 65 are provided. The leg openings 65 are portions recessed inward in the width direction from the outer edge of the disposable diaper. Here, the outer edge in the present invention is an outer edge in the width direction W, and the outer portion is a portion occupying a certain range in the width direction W including the outer edge in the width direction W. The inner edge is an inner edge in the width direction W, and the inner portion is a portion occupying a certain range in the width direction W including the inner edge in the width direction W.

The absorbent article 1 comprises an absorbent core 31 comprising absorbent material. The absorbent core 31 comprises an absorbent material such as ground pulp or super absorbent polymer (SAP), or mixtures thereof. The absorbent core 31 may be covered with a core wrap (not shown). An absorbent body may be configured by the absorbent core 31 and the core wrap. The core wrap may be made of tissue or SMS non-woven fabric, and may be arranged on the skin side T1 of the absorbent core 31 and the non-skin side T2 of the absorbent core 31 . As shown in FIG. 3, the absorbent article 1 has a skin-side sheet 20 positioned closer to the skin surface side T1 than the absorbent core 31 is. The skin-side sheet 20 covers the absorbent core 31 and is arranged over the entire absorbent article 1 . The skin-side sheet 20 of this embodiment includes a top sheet 21, a second sheet 23, and a core wrap. The top sheet 21 has a center sheet 21</b>C arranged across the center of the absorbent core 31 in the width direction W and side sheets 21</b>S covering the outer side of the top sheet 21 . The top sheet 21 may be composed of, for example, a liquid-permeable sheet such as nonwoven fabric or perforated plastic film.

Each of the pair of side sheets 21S may constitute leak-proof gathers. The inner portions of the side sheets 21S are folded back and overlapped, and a leak-proof elastic member 61 that stretches in the front-rear direction L may be provided between the overlapped side sheets 21S. The leak-proof elastic member 61 may be made of a thread rubber that stretches and contracts in the front-rear direction L. As shown in FIG. The leakage-preventing gathers stand up on the skin surface side T1 due to contraction of the leakage-preventing elastic member 61, and form a wall that prevents side leakage on the sides of the center in the width direction of the absorbent article 1. FIG.

As shown in FIG. 4, the absorbent article 1 may have at least a sheet pressing portion 28 in which the top sheet 21 is compressed in the thickness direction. A plurality of sheet pressing units 28 may be provided at intervals in plan view. The sheet pressing portions 28 of the present embodiment are dot-shaped and are spaced apart in the front-rear direction L and spaced apart in the width direction W. As shown in FIG. The sheet pressing part 28 may be configured to be visible from the skin surface side T<b>1 of the absorbent article 1 . In the present embodiment, the center seat 21C constituting the top sheet 21 is provided with the sheet pressing portion 28, and the side seat 21S is not provided with the sheet pressing portion 28. As shown in FIG. The sheet pressing section 28 may be provided on a functional sheet 45 which will be described later.

The absorbent article 1 has a non-skin side sheet 25 located on the non-skin side T2 of the absorbent core 31 . The non-skin-side sheet 25 covers the absorbent core 31 and is arranged over the entire disposable diaper. The non-skin-side sheet 25 of this embodiment includes a leak-proof sheet 26 and a back sheet 27 . The leak-proof sheet 26 is a liquid-impermeable sheet, and an air-permeable resin film is bonded to a non-woven fabric such as a polyethylene sheet, a laminated non-woven fabric mainly composed of polypropylene or the like, an air-permeable resin film, spunbond, or spunlace. It is possible to use a sheet or the like that has The back sheet 27 may be provided on the non-skin surface side T<b>2 of the leak-proof sheet 26 . The back sheet 27 may be made of liquid-permeable nonwoven fabric. The length of the leak-proof sheet 26 in the width direction W is shorter than the length of the back sheet 27 in the width direction W, and the length of the leak-proof sheet 26 in the front-rear direction L is longer than the length of the back sheet 27 in the front-rear direction L. Short is fine.

The absorbent article 1 is provided with a fastening tape 90 . The fastening tape 90 is provided in the rear waist region S2. The target portion 95 is provided in the front waist region S1. Therefore, the back waist region S2 of the present embodiment constitutes the first waist region of the first waist member and the second waist member covering the waist of the wearer, and the front waist region S1 constitutes the second waist region. do. The fastening tape 90 has a base portion 92 and a locking portion 93 . At least part of the base portion 92 is joined between the skin-side sheet 20 and the non-skin-side sheet 25 and extends outward in the width direction W from the skin-side sheet 20 and the non-skin-side sheet 25 . The locking portion 93 is provided on the base portion 92 and detachably fixed to the target portion 95 (see FIG. 2) of the front waist region S1. The fastening tape 90 extends along the width direction W in the rear waist region S2 and is attached to the target portion 95 to hold the absorbent article 1 to the wearer's body. The target portions 95 are arranged in the front waist region S1, and are configured so that the fastening tapes 90 are respectively fixed. In a modified example, the absorbent article 1 may be configured such that the fastening tape 90 is attached to the non-skin-facing surface of the non-skin-side sheet 25 without the target portion.

The absorbent article 1 has a waist opening 66 that surrounds the waist of the wearer. The waist opening 66 is formed by the rear edge 10R and the front edge 10F of the disposable diaper, and is a portion that surrounds the waist with the fastening tape 90 attached to the target portion 95. As shown in FIG. A leg elastic member 67 extending in the front-rear direction L may be provided between the skin-side sheet 20 and the non-skin-side sheet 25 . The leg elastic members 67 may be arranged outside the absorbent core 31 in the width direction W along the leg openings 65 at least in the crotch region S3. In a modified example, a waist elastic member extending in the width direction W may be provided between the skin-side sheet 20 and the non-skin-side sheet 25 . The contraction of the waist elastic member can improve the fit around the wearer's waist.

The absorbent article 1 has a functional sheet 45 . The functional sheet 45 has an oil placement region R31 in which vegetable oil is placed. The oil placement region R31 is a region where vegetable oil is placed in plan view. Any vegetable oil may be used as long as it can impart suitable benefits to the wearer, and examples thereof include olive oil, jojoba oil, rice oil, shea butter, tea oil, aloe oil, argan oil, and peach oil. Examples of olive oil include extra virgin olive oil, virgin olive oil, ordinary virgin olive oil, lampante virgin olive oil, refined olive oil, pure olive oil, refined olive pomace oil, and olive pomace oil. By arranging the olive oil, it is possible to impart the effects of the olive oil to the wearer or the like. The benefits of olive oil include, for example, moisturizing the skin, moisturizing the skin, keeping the skin smooth, and imparting fragrance.

Preferably, the vegetable oil may be a vegetable oil having an oleic acid content of 55% or more and 83% or less. Examples of the vegetable oil include olive oil, rapeseed oil, and peanut oil. A vegetable oil having an oleic acid content of 55% or more and 83% or less is relatively difficult to be oxidized and deteriorated among vegetable oils. By suppressing the deterioration of the vegetable oil, the deterioration of the color and fragrance due to oxidation is suppressed, and the wearer or the like is less likely to feel uncomfortable with the fragrance, and can continue to use the oil with peace of mind. The content of oleic acid can be measured based on the GC-MS (Japanese Agricultural Standards) "Procedure for measuring the ratio of oleic acid to fatty acids in edible vegetable oils and fats".

The olive oil may have an acid number of 6.6 mg/g or less and a peroxide number of 30 meq/mg or less. As described above, a plurality of types of olive oil are distributed, which are classified according to quality grades and the like. There is room for improvement from the viewpoint of selecting an appropriate olive oil while suppressing adverse effects such as irritation to the skin, deterioration of the olive oil, and deterioration of constituent members constituting the absorbent article 1 when the absorbent article 1 is provided with the olive oil. was there. As a result of extensive research by the applicant, it was found that olive oil having an acid value of 6.6 mg/g or less and a peroxide value of 30 meq/mg or less is suitable. Examples of olive oil having an acid value of 6.6 mg/g or less and a peroxide value of 30 meq/mg or less include extra virgin olive oil, virgin olive oil and ordinary virgin olive oil. Olive oil having an acid value of 6.6 mg/g or less is not oxidized, and the skin can be brought into contact with olive oil that is not oxidized. Oxidized (high acid value) olive oil increases lower fatty acids and may irritate the skin. However, by specifying the acid value, it is possible to provide absorbent articles containing olive oil that are safe for consumers. In addition, since the peroxide value is 30 meq/mg or less, it is possible to provide consumers with absorbent articles containing non-oxidized olive oil. Since the olive oil has a peroxide value of 30 meq/mg or less, it is difficult for the olive oil to be automatically oxidized and hardly generate hydroperoxides. When hydroperoxide is produced, it is decomposed by metal ions, and via peroxy radicals, hydroperoxide is produced again, further increasing the peroxide value. A high peroxide value may cause irritation to the skin. However, it is possible to easily maintain the low peroxide value of olive oil and provide an absorbent article that suppresses irritation to the skin. In addition, since olive oil is originally an unsaturated fatty acid that is difficult to oxidize, by using olive oil with a low peroxide value from the time of blending, it is possible to provide an absorbent article that further suppresses skin irritation. Since the olive which has not deteriorated can be applied, the deterioration of the color and fragrance is suppressed, and the wearer can continue to use it without worrying that the wearer will not feel uncomfortable with the fragrance.

Here, the acid value and peroxide value of olive oil can be measured by the following methods. The acid value can be measured using test paper AV-CHECK/ADVANTEC for judging the degree of degradation of fats and oils by heating. Specifically, 5 ml of olive oil to be measured is measured, and the olive oil is adhered to a test paper. After 2 seconds have passed, the object to be measured on the test paper is wiped off with filter paper. After 30 seconds have passed, the color of the test paper is checked, and the acid value is measured by visually comparing the color of the color sample with that of the test paper. Moreover, the peroxide value can be measured using POV test paper (peroxide value test paper)/SIBATA (Shibata Kagaku). Specifically, 5 ml of olive oil to be measured is measured and attached to the front surface of the test section. After 3 minutes, rinse with tap water until evenly colored. Next, the water is wiped off, and the color of the test paper is confirmed after being placed on a flat place for 20 seconds, and the peroxide value is measured by visually comparing the color sample and the color of the test paper.

The functional sheet 45 is a sheet arranged outside the absorbent core 31 in the thickness direction T and coated with vegetable oil. The functional sheet 45 constitutes at least one of the sheets located outside the absorbent core 31 in the thickness direction T. As shown in FIG. Functional sheet 45 of the present embodiment constitutes center sheet 21</b>C as top sheet 21 . In a modification, the functional sheet 45 may constitute the second sheet 23, the side sheets 21S, the back sheet 27 and the core wrap. Preferably, the functional sheet 45 may be arranged on the outer surface of the absorbent article. The outer surface of the absorbent article includes the skin-facing surface 1T and the non-skin-facing surface 1B. The skin-facing surface 1T of the absorbent article 1 is constituted by the skin-facing surface of the top sheet 21 including the skin-facing surface of the pair of side sheets 21S and the skin-facing surface of the center sheet 21C positioned between the side sheets 21S. ing. The non-skin facing surface 1B of the absorbent article 1 is constituted by the non-skin facing surface of the backsheet 27 . Since the functional sheet 45 is arranged on the outer surface of the absorbent article, it is easy for the wearer, etc., to come into direct contact with the functional sheet 45, and the effects of the vegetable oil can be imparted to the wearer, etc. More specifically, the topsheet 21 is a sheet that contacts the wearer's skin. Since the vegetable oil is arranged on the skin-facing surface of the top sheet, the vegetable oil easily comes into contact with the wearer's skin. In addition, the back sheet 27 is a portion that is easily touched by an assistant such as a mother when taking it out. Since the vegetable oil is arranged on the non-skin facing surface of the back sheet 27, the vegetable oil easily comes into contact with the skin of the wearer such as a mother. Vegetable oils can help keep your skin hydrated and smooth. In particular, when the back sheet 27 is in the form of a nonwoven fabric, the skin of the wearer can be protected even if the nonwoven fabric is repeatedly touched. The side sheets 21S constitute side flaps that extend outward in the width direction from the absorbent core 31 . In general, when the absorbent article is attached to the wearer, the wearer uses side flaps that do not contact the excretory opening rather than grasping the core arrangement area (the area where the core is arranged) that contacts the excretory opening. tend to grab In addition, the wearing assistant holds the side flaps even when unfolding the diaper. By providing the arrangement area in the side flaps, the installation assistant can easily touch the side seat 21S and the back seat 27 in the process of the installation operation, and can feel the presence of the vegetable oil.

The center sheet 21C that constitutes the functional sheet 45 may be made of a nonwoven fabric having fibers. FIG. 5A is an enlarged schematic diagram showing fibers 55 that constitute the nonwoven fabric. FIG. 5B is a schematic cross-sectional view showing a DD cross-sectional view of FIG. 5A. FIG. 6 is an enlarged cross-sectional photograph of a functional sheet. Fibers 55 forming center sheet 21</b>C of the present embodiment have fiber main body 551 and oil layer 552 . The surface of the fiber body 551 is covered with an oil layer 552 made of a hydrophilic fiber treatment agent. Vegetable oil is present in the oil layer 552 . The oil layer 552 covering the fiber main body 551 in this manner provides the component with vegetable oil. Therefore, it is easy to arrange the vegetable oil uniformly over the entire center seat 21C. The vegetable oil can be placed not only on the skin-facing surface and the non-skin-facing surface of the center sheet 21C, but also on the inner portion in the thickness direction. When the wearer's skin touches the fibers of the functional sheet 45, the oil layer covering the surface of the fibers forming the portion touched by the wearer is easily transferred to the wearer. In addition, since the oil layer is hydrophilic, body fluids such as sweat easily move to the skin surface side. For example, even if the wearer's hands are wet with sweat or the like, the water is absorbed by the center sheet 21C, and the feel of the surface of the back sheet 27 can be improved. In addition, as shown in FIG. 5, the gap G between the fibers 55 constitutes a non-arrangement area where the fiber main body 551 and the oil layer 552 are not arranged and the vegetable oil is not arranged. In FIG. 3, the area where the backseat 27 is arranged is shown as an oil arrangement area R31 for the sake of convenience, since the non-arrangement area is slightly smaller than the oil arrangement area R31. In a modified example, the functional sheet 45 may be obtained by applying vegetable oil or a fiber treatment agent containing vegetable oil to the constituent members such as the center sheet 21C after forming the constituent members.

The vegetable oil may be placed on each of the skin-facing surface of the center sheet 21C and the non-skin-facing surface of the center sheet 21C. Further, the center sheet 21C may have a penetration area over the entire thickness direction T of the center sheet 21C to which vegetable oil is not applied. The penetrating region is, for example, a region where gaps G between fibers are continuous in the thickness direction T. In the penetration region, the vegetable oil is not disposed over the entire thickness direction T of the center sheet 21C, and the vegetable oil is not disposed over the entire plane of the back sheet 27 . Compared to the configuration in which the vegetable oil is arranged over the entire plane of the center seat 21C, it is difficult for the vegetable oil to constantly touch the skin, and stickiness due to the vegetable oil can be suppressed. The penetrating region is composed of a portion where the portion between the fibers 55 in the center sheet 21C including the oil layer 552 containing the vegetable oil is continuous in the thickness direction, and a non-applied region of the vegetable oil in the configuration in which the vegetable oil is applied after the back sheet 27 is molded. .

The basis weight of the vegetable oil on the outer surface 451 of the functional sheet 45 is higher than the basis weight of the vegetable oil on the inner surface 452 of the functional sheet 45 . When the functional sheet 45 is arranged on the outer surface of the absorbent article 1, when the wearer touches the functional sheet 45, the vegetable oil can be transferred to the wearer. effect can be given. Further, when the functional sheet 45 is arranged inside the outer surface of the absorbent article 1 (for example, the second sheet 23), when the outer surface of the absorbent article 1 is pressed, the absorbent article 1 The vegetable oil easily exudes to the outer surface of the mask, and the effect of the vegetable oil can be imparted to the wearer or the like. The inner surface of the functional sheet 45 is joined to other constituent members located inside the functional sheet 45 with an adhesive or welded to other constituent members. At this time, since the basis weight of the vegetable oil on the inner surface 452 of the functional sheet 45 is relatively low, problems such as difficulty in bonding with the adhesive due to the arrangement of the vegetable oil can be suppressed.

The basis weight of the vegetable oil on the outer surface of the functional sheet and the basis weight of the vegetable oil on the inner surface of the functional sheet can be compared by the following method. Two pieces of filter paper are prepared and each is impregnated with hexane. One filter paper is applied to the outer surface of the functional sheet, the other filter paper is applied to the inner surface of the functional sheet, and the vegetable oil of the functional sheet is transferred to each of the two filter papers. Based on the basis weight of the vegetable oil transferred to the filter paper, the basis weight of the vegetable oil on the outer surface of the functional sheet and the basis weight of the vegetable oil on the inner surface of the functional sheet are compared. The basis weight of the vegetable oil transferred to the filter paper can be measured by well-known methods, for example, high performance liquid chromatography (HPLC) method can be used. In addition, when vegetable oil is contained substantially uniformly in the fiber treatment agent, by comparing the basis weights of the fiber treatment agents, the comparison result can be replaced with the comparison result of the vegetable oil.

As shown in FIG. 4, the functional sheet 45 may have an outer region R11 extending inwardly from the outer surface 451 of the functional sheet 45 and an inner region R12 extending outwardly from the inner surface 452 of the functional sheet 45. . The outer region R11 and the inner region R12 may be adjacent to each other. The outer region R11 of the present embodiment extends from the skin-facing surface of the center seat 21C to the non-skin surface side T2, and the inner region R12 is positioned closer to the non-skin surface side T2 than the outer region R11. It extends from the skin facing surface to the skin surface side T1. The average fiber diameter of the outer region R11 is smaller than the average fiber diameter of the inner region R12. That is, the outer region R11 is a region having a smaller average fiber diameter than the inner region R12. The outer region R11 has a relatively smaller average fiber diameter and tends to have a larger fiber surface area than the inner region R12. A surface area to which vegetable oil can adhere can be secured, and the content of vegetable oil in the outer region R11 can be increased. On the other hand, the inner region R12 has a relatively large average fiber diameter compared to the outer region R11, and tends to have larger voids between the fibers. The adhesive in contact with the inner region R12 easily enters the gaps between the fibers, and the adhesive strength of the adhesive can be easily secured. The thickness of the inner region R12 may be thicker than the thickness of the outer region R11. By increasing the thickness of the inner region where it is easy to secure the voids between the fibers, it is easy to hold the adhesive, and it is easier to secure the adhesive strength of the adhesive.

In addition, the average fiber diameter can be measured by the following method. Cut the functional sheet into a size of 10 mm×10 mm with scissors. Place the sample on the viewing plate so that the outer region of the cut sample abuts the viewing plate. Observe the cross section using a digital microscope VHX-7000/KEYENCE, and measure the fiber diameter of the fibers that make up the sample. For the fiber diameter, the average value of the fiber diameters of 10 cut fibers is used. The boundary between the outer region R11 and the inner region R12 may be a location where eight or more of the ten cut fibers have different diameters.

The average fiber diameter of the outer region R11 may be 1.7 dtex or less, and the average fiber diameter of the inner region R12 may be 3.3 dtex or more. Since the average fiber diameter of the inner region R12 is 3.3 dtex or more, and the fiber diameter is relatively large, it is easy to secure voids between fibers. In addition, since the average fiber diameter of the outer region R11 is 1.7 dtex or less and the fiber diameter is relatively small, the gaps between the fibers tend to be small. Therefore, it is difficult for body fluids and adhesives that have entered the gaps G between the fibers of the inner region R12 to migrate to the outer region R11. Therefore, it is possible to retain the adhesive in the inner region R12 to ensure adhesive strength, retain body fluid in the inner region R12, and suppress rewetting of the outer surface of the absorbent article. In addition, when the functional sheet 45 constitutes the outer surface of the absorbent article 1, when the wearer or the like touches the functional sheet 45, the functional sheet 45 is softly deformed, feels smooth on the skin, or is soft to the touch. It is easy to have a feeling that is gentle on the skin. Therefore, in addition to the efficacy of the vegetable oil, it is easy for the wearer to recognize that the absorbent article 1 is gentle on the skin.

The thickness of the inner region R12 may be thicker than the thickness of the outer region R11. By increasing the thickness of the inner region where it is easy to secure the voids between the fibers, it is easy to retain the body fluid drawn inward in the thickness direction, and the drawability of the body fluid can be improved. Preferably, the ratio of the thickness of the inner region R12 to the entire functional sheet 45 may be 80% or more. It is easier to ensure the voids between the fibers, and the effect of improving the adhesive strength of the adhesive and the ability to attract body fluids can be exhibited. The thickness of the inner region R12 and the thickness of the outer region R11 are measured by observing the cross section using a digital microscope VHX-7000/KEYENCE in the same manner as in the method for measuring the average fiber diameter.

The density of the vegetable oil in the outer region R11 may be higher than the density of the vegetable oil in the inner region R12. The outer region R11 of the functional sheet 45 is located outside the inner region R12 in the thickness direction T, is close to the outer surface of the absorbent article 1, and has a high density of vegetable oil. Therefore, when the functional sheet 45 is arranged on the outer surface of the absorbent article 1, when the wearer touches the functional sheet 45, the vegetable oil can be transferred to the wearer. can give the efficacy of vegetable oil. Further, when the functional sheet 45 is arranged inside the outer surface of the absorbent article 1 (for example, the second sheet 23), when the outer surface of the absorbent article 1 is pressed, the absorbent article 1 The vegetable oil easily exudes to the outer surface of the mask, and the effect of the vegetable oil can be imparted to the wearer or the like. The inner region R12 where the density of vegetable oil is low constitutes the inner surface of the functional sheet 45, and is in contact with other constituent members (leakage-proof film, core wrap, second sheet, elastic member) located inside the functional sheet 45. , is joined to another component via an adhesive, or is welded to another component. At this time, since the density of the vegetable oil is relatively low, problems such as difficulty in bonding with the adhesive due to the arrangement of the vegetable oil can be suppressed.

The density of fibers in the inner region R12 may be lower than the density of fibers in the outer region R11. Since the density of the fibers in the inner region R12 is lower than the density of the fibers in the outer region R11, it is easy to secure the gaps G between the fibers. The adhesive in contact with the inner region R12 easily enters the gaps between the fibers, and the adhesive strength of the adhesive can be easily secured. In addition, the body fluid drawn into the functional sheet 45 can be easily retained, and the drawability of the body fluid can be improved.

An elastic member may be bonded to the inner surface (the inner surface in the thickness direction) of the functional sheet 45, and the vegetable oil may be provided in a region overlapping the elastic member. The elastic member can be exemplified by the leg elastic member 67 and the waist elastic member. Since the basis weight of the vegetable oil on the inner surface of the functional sheet 45 is low, the bonding state of the elastic member to the functional sheet 45 can be maintained. In addition, the elastic member is a portion that comes into close contact with the body, and the wearer or the like tends to touch the region overlapping the elastic member in order to adjust the positions of the elastic member and the part of the body. By arranging the elastic member in the region overlapping with the elastic member, the wearer, etc. can easily touch the vegetable oil in the process of adjusting the position of the elastic member, and the effects of the vegetable oil can be imparted to the wearer, etc.

The backsheet 27 may have non-deployed areas where no vegetable oil is applied. The non-arrangement area may be provided in the target portion 95 . Since vegetable oil is not placed on the target portion to which the fastening tape 90 adheres, it is possible to suppress the deterioration of the engaging force of the fastening tape due to the oil content, thereby maintaining the state of adhesion between the fastening tape and the target portion. Preferably, the non-arrangement region may be provided in at least part of the target portion, but preferably the non-arrangement region may be provided over the entire target portion 95 . The non-arranged areas are constituted by the portion of the fibers 55 in the backsheet 27 that includes the oil layer 552 with vegetable oil, and the non-applied area of vegetable oil in the configuration in which the vegetable oil is applied after the backsheet 27 is molded.

The functional sheet 45 may be provided with a sheet pressing portion 28 obtained by compressing at least the functional sheet 45 in the thickness direction. At least part of the vegetable oil may be provided in the sheet pressing section. When forming the sheet pressing portion, generally, the functional sheet is pressed by pressing the convex portion corresponding to the sheet pressing portion against the functional sheet. At this time, the protrusions are in close contact with the functional sheet and may be difficult to separate from the functional sheet. However, since the vegetable oil is arranged in the portion forming the sheet pressing portion, the convex portion pressed against the sheet pressing portion tends to separate from the sheet pressing portion. Therefore, the convex portion and the sheet compressing portion can be smoothly separated from each other without providing the convex portion with a surface treatment for facilitating the separation of the convex portion and the sheet pressing portion, thereby improving manufacturing efficiency.

Although the present invention has been described in detail using the above embodiments, it will be apparent to those skilled in the art that the present invention is not limited to the embodiments described herein. The present invention can be implemented with modifications and variations without departing from the spirit and scope of the invention defined by the claims. Accordingly, the descriptions herein are for the purpose of illustration and description, and are not intended to have any limiting meaning with respect to the present invention.

According to the present invention, it is possible to provide an absorbent article having a functional sheet to which vegetable oil is applied, in which adhesive force between the functional sheet and other constituent members can be easily ensured.

1: Absorbent article, 20: Skin-side sheet, 21: Top sheet (functional sheet), 21C: Center sheet, 21S: Side sheet, 23: Second sheet, 25: Non-skin-side sheet, 26: Leak-proof sheet, 27: Back sheet, 31: Absorbent core, 45: Functional sheet, 451: Outer surface of functional sheet, 452: Inner surface of functional sheet, S1: Front waist region, S2: Back waist region, S3: Crotch region, T : thickness direction, T1: skin surface side, T2: non-skin surface side, L: longitudinal direction, W: width direction, R11: outer region, R12: inner region, R31: oil arrangement region

Claims (7)

an absorbent core;
a functional sheet arranged outside the absorbent core in the thickness direction and to which vegetable oil is applied, wherein
The basis weight of the vegetable oil on the outer surface of the functional sheet in the thickness direction is higher than the basis weight of the vegetable oil on the inner surface of the functional sheet in the thickness direction,
The functional sheet is a nonwoven fabric having fibers,
The functional sheet has an outer region extending inwardly from the outer surface of the functional sheet and an inner region extending outwardly from the inner surface of the functional sheet,
The average fiber diameter of the outer region is smaller than the average fiber diameter of the inner region,
The functional sheet is arranged on the outer surface of the absorbent article,
The fiber has a fiber body and an oil layer covering the surface of the fiber body and made of a hydrophilic fiber treatment agent,
The vegetable oil is contained in the oil layer,
The absorbent article , wherein the density of the fibers in the inner region is lower than the density of the fibers in the outer region . An elastic member is joined to the inner surface of the functional sheet,
The absorbent article according to claim 1, wherein the vegetable oil is provided in a region overlapping with the elastic member. 3. The absorbent article according to claim 1 or 2, wherein the thickness of the inner region is thicker than the thickness of the outer region. The average fiber diameter of the outer region is 1.7 dtex or less,
The absorbent article according to any one of claims 1 to 3, wherein the inner region has an average fiber diameter of 3.3 dtex or more. 5. The absorbent article according to any one of the preceding claims, wherein the density of the vegetable oil in the outer region is higher than the density of the vegetable oil in the inner region. Having a sheet pressing part that compresses at least the functional sheet in the thickness direction,
The absorbent article according to any one of claims 1 to 5 , wherein at least part of said vegetable oil is provided in said sheet pressing portion. The absorbent article according to any one of claims 1 to 6 , wherein the vegetable oil has an oleic acid content of 55% or more and 83% or less.

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