JP6157447B2 - Absorbent articles - Google Patents

Description

  The present invention relates to an absorbent article having a gel composition on its surface.

  Absorbent articles such as disposable diapers, sanitary napkins, panty liners, incontinence pads, etc. have improved basic performance such as absorption performance due to technology development accumulated over many years. After absorbing the excrement, it has become difficult to cause leakage, and at present, there is a demand for further enhancement of functionality, for example, having a skin care effect and a comfortable wearing feeling. Absorption that can prevent skin irritation and the like while improving liquid permeability by applying a lotion agent containing skin care ingredients etc. on the top sheet as such highly functional absorbent articles Sexual goods etc. have been proposed.

  For example, Patent Document 1 discloses a liquid-impermeable back sheet and a liquid-permeable top sheet joined to the back sheet, and the inner side of the article when a disposable absorbent article is worn. A topsheet having a facing inner surface and an outer surface facing toward the wearer's skin, and having a lotion on at least a portion of the outer surface of the topsheet; and an absorbent core disposed between the topsheet and the backsheet; A liquid permeable topsheet in the form of a pattern comprising a plurality of strips, wherein the strip is separated by a plurality of non-lotion areas, and the pattern comprising a plurality of strips is Disposable absorbent articles are disclosed that are discontinuous patterns. Furthermore, according to Patent Document 1, the absorbent article having the liquid-permeable top sheet thus provided with a lotion is said to have a comfortable wearing feeling, excellent liquid treatment characteristics, and a smooth feeling.

  Patent Document 2 discloses an absorbent article comprising a liquid-permeable top sheet made of a nonwoven fabric, a liquid-impermeable or water-repellent back sheet, and an absorber disposed between the two sheets. The top sheet has a number of protrusions that protrude toward the wearer's skin, the protrusion has an internal space that is open on the absorber side, and the protrusion is the skin at the top. An absorbent article is disclosed in which a skin care agent is attached to both the facing surface and the non-skin facing surface, and the skin facing surface has a larger amount of skin care agent per unit area than the non-skin facing surface at the top. ing. Furthermore, according to Patent Document 2, the absorbent article to which the skin care agent is attached as described above can stably hold the skin care agent at a site that is easily transferred to the skin, and is excellent in skin care effect and its sustainability. .

Japanese translation of PCT publication No. 2008-522772 JP 2012-143543 A

  However, the lotion and skin care agent (hereinafter referred to as “lotion etc.”) used in the absorbent articles of Patent Documents 1 and 2 are the body temperature of the wearer and the temperature of excrement when the absorbent article is worn. Since the melted lotion or the like penetrates to the non-skin side surface of the top sheet, the hot melt adhesion to the core wrap sheet that contacts the non-skin side surface of the top sheet Bonding by the agent is hindered, the surface sheet and the core wrap sheet are separated, and there is a possibility that the absorbability of the absorbent article is lowered.

  Therefore, the present invention is an absorbent article in which a gel-like composition is coated on a surface sheet, and is excellent in dryness and liquid permeability in the thickness direction on the surface, and between the surface sheet and the core wrap sheet. An object of the present invention is to provide an absorbent article that is excellent in absorbency while maintaining the bonding state between the two.

  The present invention includes an absorbent body including an absorbent core and a core wrap sheet surrounding the absorbent core, and a top sheet disposed on the skin surface side of the absorbent body and bonded to the core wrap sheet by an adhesive. Regarding the absorbent article, the topsheet is absorbed on the skin surface side surface of the topsheet intermittently with a hydrophobic gel-like composition capable of maintaining a gel state at 38 ° C. It is a sex product. In the absorbent article of the present invention, since the gel composition can maintain a gel state even at 38 ° C., when the absorbent article is worn, it does not melt due to the body temperature of the wearer and the non-skin of the topsheet Since the gel-like composition does not penetrate into the surface side, the bonding state between the top sheet and the core wrap sheet is not affected, and the bonding state is stably maintained for a long time. Can do.

  Further, the hydrophobic gel-like composition is intermittently applied to the surface on the skin surface side of the surface sheet composed of hydrophilic fibers and the like, so that the surface on the skin surface side of the surface sheet is formed. In addition, while the coating region of the hydrophobic gel-like composition is formed, the inside of the topsheet has hydrophilicity, so that the hydrophobic water repellency in the coating region and the inside of the topsheet Liquid excrement such as urine supplied on the skin side surface of the top sheet by a synergistic action with hydrophilic water absorption through the non-coated region where the gel composition is not applied. Thus, it is possible to form a state that is easily pulled into the inside of the top sheet, and thereby it is possible to significantly improve the liquid repellency of the top sheet while maintaining the liquid permeability in the thickness direction. Further, even when the body pressure of the wearer is applied to the surface sheet, and the liquid excretion penetrating into the surface sheet moves toward the skin surface side of the surface sheet, the hydrophobic gel-like composition remains on the surface. The presence of the liquid excrement on the skin surface side of the sheet inhibits the liquid excretion from leaching to the skin side surface of the top sheet, so that the liquid excretion that has once permeated the inside is effectively returned. Can be prevented. As a result, the absorbent article can be made into an absorbent article having excellent surface dryness while maintaining liquid permeability in the thickness direction.

  Furthermore, the gel composition is not applied to the non-skin surface side of the top sheet, and the gel composition applied to the skin side surface of the top sheet is, Since it does not permeate the non-skin surface side surface of the top sheet, the surface of the top sheet as the liquid excretion penetrating from the skin surface side to the non-skin surface side of the top sheet goes to the non-skin side surface. In order to facilitate diffusion in the direction, the liquid excrement reaching the non-skin side surface of the top sheet while diffusing in the surface direction of the top sheet is joined to the non-skin side surface of the top sheet. Through the core wrap sheet, the absorbent core can absorb from a wide range, thereby further improving the absorption efficiency of the liquid excreta into the absorber. As a result, an absorbent article having excellent absorbability can be obtained.

  ADVANTAGE OF THE INVENTION According to this invention, while providing the dryness in the surface and the liquid permeability of a thickness direction, providing the absorbent article excellent also in the absorptivity, maintaining the joining state between a surface sheet and a core wrap sheet | seat. can do.

Drawing 1 is a top view in the state where the absorptive article concerning one embodiment of the present invention extended. FIG. 2 is a partial cross-sectional view (schematic diagram) in the width direction of the portion where the gel-like composition is applied in the absorbent article according to one embodiment of the present invention.

  The absorbent article of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a plan view of an absorbent article (disposable diaper) according to an embodiment of the present invention in a stretched state, and FIG. 2 is a gel composition in the absorbent article according to an embodiment of the present invention. It is a fragmentary sectional view (schematic diagram) in width direction _DW of a portion to which was applied intermittently. The disposable diaper 1 according to an embodiment of the present invention has an outer shape that is long in the longitudinal direction D _L in a plan view in an extended state, and a central portion in the longitudinal direction D _L is in the width direction D _W. It has a substantially hourglass shape (or inverted crown shape) narrowed toward the inward side. Incidentally, the absorbent article of the present invention is not limited to such contour, employing for example, gourd-shaped or rectangular like a rectangular, elliptical, long arbitrary shape in the longitudinal direction D _L, such as oval can do. As shown in FIGS. 1 and 2, the disposable diaper 1 according to this embodiment includes a liquid-permeable surface sheet 2 positioned on the skin surface side of the wearer in the thickness direction _DT , and the skin surface side surface. It has a laminated structure including a liquid-impermeable back sheet 3 positioned on the opposite side (that is, the non-skin surface side) and an absorbent body 4 positioned between the top sheet 2 and the back sheet 3. Further, a pair of side sheet members for forming a gather part, which is disposed on the skin surface side of the top sheet 2 so as to sandwich the top sheet 2 from the outside in the width direction _DW in plan view. 5 is provided. Further, the surface of the skin surface side of the topsheet 2 is a region where gel composition described below is applied, extending in the longitudinal direction D _L of the disposable diaper 1, and in the width direction D _W It has the application area | region 6 (Hereinafter, it may describe as a "linear coating area | region.") Of the some substantially linear gel-like composition located in a line.

  And in the absorbent article of this invention, the said gel-like composition is a hydrophobic gel-like composition which can maintain a gel state at 38 degreeC. Hereinafter, the gel composition used for the absorbent article of the present invention will be described in more detail.

[Gel composition]
The gel composition used in the absorbent article of the present invention is not particularly limited as long as it can maintain a gel state at 38 ° C. and has a hydrophobic property. For example, styrenic elastomers and hydrocarbon oils can be used. Among them, a composition containing a styrene elastomer, hydrocarbon oil, and silicone oil is preferably used. Among them, the gel composition has a weight average molecular weight of 100,000 or more and less than 180,000, and a styrene-based thermoplastic elastomer (A1) composed of a block copolymer of triblock or more, and a weight average molecular weight of 180,000 or more. A styrene-based thermoplastic elastomer (A2) composed of a block copolymer of 300,000 or less and a triblock or more in a mass ratio of (A1) / (A2) = 95/5 to 50/50, and The kinematic viscosity at 37.8 ° C. is 5 to 50 mm ² / s with respect to 100 parts by mass of the styrene-based thermoplastic elastomer mixture (A) having a molecular weight dispersity (Mw / Mn) of 1.25 to 1.60. and there hydrocarbon oil (B) a 500-4800 parts by mass, kinematic viscosity at 25 ° C. contains a silicone oil (C) 20 to 60 parts by weight is 50 to 200 mm ² / s The Narubutsu, can be particularly preferably used.

  The styrenic thermoplastic elastomer (A1, A2) used in the above-mentioned gel composition is a block copolymer of triblock or more including a polystyrene hard segment and a soft segment, and preferably comprises a styrene hard segment. It is a block copolymer having two or more block components in a molecular chain, and more preferably a block copolymer in which the block components at least at both ends in the molecular chain are block components composed of the styrene hard segment. The polystyrene hard segment is not particularly limited, and examples thereof include polystyrene, poly (α-methylstyrene), poly (o-methylstyrene), poly (m-methylstyrene), and poly (p-methylstyrene). Examples thereof include polystyrene polymers. The soft segment is not particularly limited, and examples thereof include polyolefin polymers such as polyethylene, polypropylene, polybutylene, polybutadiene, and polyisoprene.

  The copolymer used as the styrene-based thermoplastic elastomer (A1, A2) is not particularly limited as long as it is a styrene-based block copolymer of triblock or more. For example, a styrene-butadiene-styrene block copolymer ( SBS), styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-isoprene-butylene-styrene block copolymer (SIBS), styrene-isoprene-styrene block copolymer (SIS), styrene-ethylene- Examples thereof include a propylene-styrene block copolymer (SEPS), a styrene-ethylene-ethylene-propylene styrene block copolymer (SEEPS), and an arbitrary combination of two or more thereof. Among these, a styrene-ethylene-butylene-styrene block copolymer (from the viewpoint of gel state retention (particularly retention at 38 ° C.), gel hardness, elongation, etc.) SEBS), styrene-ethylene-propylene-styrene block copolymers (SEPS) and styrene-ethylene / ethylene-propylene-styrene block copolymers (SEEPS) are preferred. When a diblock copolymer is used as the styrenic thermoplastic elastomer (A1, A2), the interaction between the styrenic hard segments (π-π stacking) is weakened. There is a possibility that sufficient state retention (particularly, retention at 38 ° C.), gel hardness, elongation, and the like may not be obtained. The styrenic thermoplastic elastomer has a network-like network structure formed by a plurality of aggregation domains formed by the interaction of the styrene hard segments and an olefinic soft segment connecting the plurality of aggregation domains. Therefore, it is considered that the gel state can be maintained even under temperature conditions of about body temperature (about 35 ° C. to about 38 ° C.) while exhibiting the function as an elastic body. Further, such a network-like network structure is considered to have a function of holding an oil agent (that is, a hydrocarbon oil (B) and a silicone oil (C)), which will be described later, while maintaining a moderately sustained release.

  The block copolymer is preferably 10 to 50% by mass of a styrene block component and 50 to 90% by mass of an olefinic block component, more preferably 15 to 40% by mass of a styrene block component and 60 to 85%. It contains a olefinic block component of mass%, particularly preferably 18 to 35 mass% of a styrene block component and 65 to 82 mass% of an olefinic block component. When the proportion of the styrene block component is less than 10% by mass, the amount of the styrene block component forming the aggregation domain decreases, and therefore the styrene thermoplastic elastomer is difficult to form the above-described network network structure. . On the other hand, when the proportion of the styrene block component exceeds 50% by mass, the amount of the olefin block component that holds the oil agent or the like decreases, so the amount of the oil agent or the like that can be held decreases, and the styrene hard segment Since the amount of the aggregation domain formed by the method increases, the gel after being applied to the top sheet becomes hard, and there is a possibility that the wearer may feel uncomfortable or uncomfortable when wearing the absorbent article.

  The styrene thermoplastic elastomer mixture (A) is composed of a mixture of two types of styrene thermoplastic elastomers (A1, A2) having different weight average molecular weights. One of the two types of styrenic thermoplastic elastomers (A1, A2) (hereinafter referred to as “low molecular weight styrenic thermoplastic elastomer (A1)”). The weight average molecular weight is in the range of 100,000 to less than 180,000, preferably in the range of 100,000 to 150,000. If the weight average molecular weight is less than 100,000, the hardness and elongation of the gel after being applied to the topsheet will be low, which may hinder the flexibility of the topsheet. The other styrene thermoplastic elastomer (A2) (hereinafter sometimes referred to as “high molecular weight styrene thermoplastic elastomer (A2)”) has a weight average molecular weight in the range of 180,000 to 300,000. Preferably, it is in the range of 220,000 to 280,000. When this weight average molecular weight exceeds 300,000, tackiness is likely to occur on the surface of the gel after it is applied to the top sheet. Therefore, when the absorbent article is worn, the wearer feels sticky and uncomfortable. There is a risk of causing it.

  The styrenic thermoplastic elastomer mixture (A) has a dispersity (that is, a ratio of weight average molecular weight (Mw) to number average molecular weight (Mn) (Mw / Mn)) within a range of 1.25 to 1.60. Yes, preferably in the range of 1.35 to 1.55. When the dispersity is less than 1.25, the physical properties of the gel composition are the same as when a single styrenic thermoplastic elastomer is used, and the gel elongation after application to the topsheet becomes insufficient, There is a risk of hindering the flexibility of the topsheet. On the other hand, if the degree of dispersion exceeds 1.60, the gel after being applied to the top sheet becomes inhomogeneous due to the difference in the cooling and solidifying time of the two types of styrene-based thermoplastic elastomers (A1, A2). There is a risk that physical properties such as elongation and brittleness will be reduced, resulting in variations in quality as an absorbent article.

  The weight average molecular weight (Mw) of the two types of styrenic thermoplastic elastomers (A1, A2) and the styrenic thermoplastic elastomer mixture (A), and the degree of dispersion of the styrenic thermoplastic elastomer mixture (A) (Mw / Mn) can be determined by polystyrene conversion by GPC measurement under the following conditions using tetrahydrofuran (THF) as a mobile phase.

[GPC measurement conditions]
Device: GPC-8220 (manufactured by Tosoh Corporation)
Column: SHODEX KF-804 (manufactured by Showa Denko KK)
Temperature: 40 ° C
Solvent: THF
Flow rate: 1.0 mL / min Sample concentration: 0.05 to 0.6% by mass
Injection volume: 0.1 mL
Detection: RI (differential refractometer)

  As described above, the gel composition contains a mixture of two types of styrene thermoplastic elastomers (A1, A2) having different weight average molecular weights, and the blending amount thereof is a low molecular weight styrene thermoplastic elastomer. The mass ratio of (A1) to high molecular weight styrenic thermoplastic elastomer (A2) is in the range of (A1) / (A2) = 95 / 5-50 / 50, preferably 90 / 10-60 / 40. More preferably, it is 80 / 20-70 / 30. When the blending ratio of the low molecular weight styrene-based thermoplastic elastomer (A1) exceeds 95 in the mass ratio, the hardness and elongation of the gel after application to the surface sheet becomes insufficient, so the flexibility of the surface sheet is increased. If the blending ratio is less than 50, tackiness is likely to occur on the surface of the gel after application to the topsheet, causing the wearer to feel sticky and possibly causing discomfort. .

The gel composition may further include a hydrocarbon oil (B) having a kinematic viscosity at 37.8 ° C. of 5 to 50 mm ² / s. The hydrocarbon oil (B) is not particularly limited as long as it is a compound composed of carbon and hydrogen, and may have a linear, branched or cyclic structure, or may have a saturated or unsaturated bond. . Examples of the hydrocarbon oil (B) include olefinic hydrocarbons (alkenes containing one double bond), paraffinic hydrocarbons (alkanes containing neither a double bond nor a triple bond), or acetylene hydrocarbons (triple). Alkyne having one bond), hydrocarbons having two or more double bonds and / or triple bonds, and cyclic hydrocarbons such as aromatic hydrocarbons and alicyclic hydrocarbons. More specifically, hydrogenated polyisobutene, liquid paraffin, squalane, squalene and the like can be mentioned. Furthermore, hydrogenated polyisobutene does not cause tackiness in the gel after being applied to the surface sheet, and is an oil agent that is gradually released. Since there is no stickiness caused by the above, it can be particularly preferably used.

Said hydrocarbon oil (B) is in the range kinematic viscosity at 37.8 ° C. is 5 to 50 mm ² / s, preferably in the range of 10 to 30 mm ² / s, more preferably 10 to 20 mm ² / s Is within the range. If the kinematic viscosity is less than 5 mm ² / s, the hydrocarbon oil (B) is likely to volatilize during the production of the gel composition, and there is a possibility that the physical properties of the gel after application to the topsheet may vary. . On the other hand, when the kinematic viscosity exceeds 50 mm ² / s, the gel after being applied to the top sheet becomes hard and tackiness tends to occur. The kinematic viscosity of the hydrocarbon oil (B) is measured at a test temperature of 37.8 ° C. using a Cannon Fenceke reverse flow viscometer according to “5. Kinematic viscosity test method” of JIS K 2283: 2000. Can be obtained.

  The blending amount of the hydrocarbon oil (B) is in the range of 500 to 4800 parts by weight, preferably in the range of 800 to 3000 parts by weight, with respect to 100 parts by weight of the styrenic thermoplastic elastomer mixture (A). More preferably, it exists in the range of 1000-1500 mass parts. If the blending amount is less than 500 parts by mass, the gel after being applied to the top sheet becomes hard and the elongation also decreases, which may impair the flexibility of the top sheet. On the other hand, if this blending amount exceeds 4800 parts by mass, the gel becomes too soft, and the gel easily penetrates into the non-skin surface side of the topsheet after being applied to the topsheet.

The gel composition may further contain a silicone oil (C) having a kinematic viscosity at 25 ° C. of 50 to 200 mm ² / s. The silicone oil (C) is not particularly limited as long as it is a silicone oil, and any known silicone oil can be used. Examples of the silicone oil (C) include diorganopolysiloxanes such as dimethylpolysiloxane and methylphenylpolysiloxane, and cyclic siloxanes such as cyclopentasiloxane. In particular, dimethylpolysiloxane can be preferably used because it can impart appropriate sustained release properties such as oils to the gel composition.

The silicone oil (C) is in the range kinematic viscosity at 25 ° C. of 50 to 200 mm ² / s, preferably in the range of 70~150mm ² / s, more preferably in the range of 80 to 120 mm ² / s It is. If the kinematic viscosity is less than 50 mm ² / s, the silicone oil (C) is likely to volatilize during the production of the gel composition, so that the physical properties of the gel after application to the top sheet may vary. On the other hand, when the kinematic viscosity exceeds 200 mm ² / s, the sustained release amount of the oil agent or the like decreases, and tackiness tends to occur. The kinematic viscosity of the silicone oil (C) is also measured at a test temperature of 25 ° C. using a Canon Fenceke reverse flow viscometer according to “5. Kinematic viscosity test method” of JIS K 2283: 2000. Can be obtained.

  The amount of the silicone oil (C) is in the range of 20 to 60 parts by mass, preferably in the range of 30 to 50 parts by mass, with respect to 100 parts by mass of the styrenic thermoplastic elastomer mixture (A). . When the blending amount is less than 20 parts by mass, the sustained release amount of the oil agent or the like decreases. On the other hand, when the blending amount exceeds 60 parts by mass, the sustained release amount of the oil agent or the like is excessively increased, and the gel surface becomes oily.

  In addition, the gel composition may contain a stabilizer, an antioxidant (for example, BHT (2,6-di-t-butyl-p-cresol), BHA (butylated hydroxyanisole), depending on desired product characteristics. , Propyl gallate, etc.), light stabilizers, colorants, pigments (eg, titanium oxide, zinc oxide, etc.), flavors, inorganic powders (eg, alumina, talc, mica, calcium carbonate, clay, etc.), organic powders Any additive such as PE (PP, PP, silicone resin powder, etc.) or other components may be included in a range that does not impair the object of the present invention.

  Examples of the other components include oils having skin care action (for example, jojoba oil, camellia oil, etc.), vitamins, various amino acids, peptides, zeolite, cholesterol, hyaluronic acid, lecithin, ceramide, skin astringent, Examples include acne agents, anti-wrinkle agents, anti-cellulite agents, whitening agents, antibacterial agents, anti-fungal agents, anti-inflammatory ingredients, pH adjusters, and moisturizers.

  Since the above-mentioned gel composition can maintain a gel state even at a temperature of 38 ° C., an absorbent article in which such a gel composition is coated on a surface sheet is worn by the absorbent article. In some cases, the gel composition does not melt due to the body temperature of the wearer, and the gel composition does not penetrate to the non-skin surface side of the top sheet as in the prior art. Does not adversely affect the bonding between the wrap sheet and the adhesive. Moreover, since the gel-like composition applied to the surface on the skin side of the surface sheet does not penetrate into the surface on the non-skin surface side of the surface sheet, the skin surface side to the non-skin surface side of the surface sheet The liquid excretion that permeates into the non-skin surface side surface becomes easier to diffuse in the surface direction of the top sheet as it goes to the non-skin surface side surface. The liquid excrement reaching the surface can be absorbed into the absorbent core from a wide range of places through the core wrap sheet joined to the non-skin surface side surface of the top sheet, thereby The absorption efficiency to the absorber can be further improved. As a result, an absorbent article having excellent absorbability can be obtained.

  Moreover, a gel-like composition can be manufactured by mixing the various compounding components mentioned above using arbitrary well-known mixing means. For example, it can manufacture by supplying the above-mentioned various compounding components into the mixing apparatus simultaneously or in any order, and melt-mixing in the mixing apparatus. There are no particular restrictions on the melt mixing means, and any known mixing means can be employed. Examples of such mixing means include mixing devices such as a single screw extruder, a twin screw extruder, a roll, a Banbury mixer, various kneaders, and a compounding pot.

  In addition to having moderate hardness and elongation, the gel-like composition described above also has sustained release properties, so that it can be applied onto a surface sheet while suppressing adhesion to various coating devices or molding devices. it can. Furthermore, since the gel composition contains more low molecular weight styrene thermoplastic elastomer than high molecular weight styrene thermoplastic elastomer, it exhibits moderate fluidity even under temperature conditions of around 100 ° C. Therefore, it is possible to easily apply the surface sheet made of a nonwoven fabric or the like with various coating patterns.

  In the absorbent article of the present invention, the coating pattern of the gel composition is not particularly limited as long as the gel composition is intermittently applied. In the range which does not inhibit the effect | action etc. of a composition, it can coat on a surface sheet by arbitrary coating patterns. In the present specification, “intermittently apply” means that a plurality of application regions and a non-application region in which the gel composition is not applied on the skin side surface of the surface sheet It is meant to be applied so that and are formed.

The absorbent article of the present invention is intermittently coated with a hydrophobic gel-like composition on the surface on the skin surface side of the surface sheet composed of hydrophilic fibers, so that the skin surface side of the surface sheet 2 On the other side, a hydrophobic gel-like composition coating region 6 as shown in FIG. 2 is formed, while the inside of the topsheet 2 has hydrophilicity, so the coating region 6 The liquid excretion U such as urine supplied on the skin side surface of the top sheet 2 by the synergistic action of the hydrophobic water repellent action and the hydrophilic water absorbing action inside the top sheet 2 It is possible to form a state that is easily drawn into the surface sheet 2 through a non-coated region where the gel-like composition is not applied, thereby maintaining liquid permeability in the thickness direction _DT. However, the liquid repellency of the top sheet 2 can be remarkably improved. Further, even when the body pressure of the wearer is applied to the top sheet 2 and the liquid excrement U that has penetrated into the top sheet 2 moves toward the skin side of the top sheet 2, a hydrophobic gel Since the composition is present on the surface of the surface sheet 2 on the skin surface side, the liquid excretion U is prevented from leaching out to the surface of the surface sheet 2 on the skin surface side. The liquid return of the thing U can be prevented effectively. As a result, the absorbent article can be made into an absorbent article excellent in surface dryness and liquid permeability in the thickness direction.

  In the present specification, “liquid repellency” means that the liquid excrement supplied on the skin surface side of the top sheet is made when it is spread from the skin surface side to the non-skin surface side. Means ease, quantified by the time it takes for the liquid excrement to burn from the surface side of the top sheet to the non-skin side and to disappear from within the top sheet (ie, “burn rate”) Can be evaluated. Further, in this specification, “liquid permeability” means that liquid excrement supplied on the skin surface side of the top sheet penetrates into the top sheet from the skin side surface. It means the ease of penetration, and the liquid excrement is quantitatively evaluated by the time taken to finish infiltrating into the surface sheet from the surface on the skin side of the surface sheet (that is, “permeation rate”). Can do.

  The bake rate and the penetration rate can be measured by the following absorbability evaluation test. In the absorbent evaluation test, first, the surface sheet is removed from the baby paper diaper, Mooney “Air Fit” S size, which is commercially available from Unicharm Co., Ltd. An absorptive evaluation test sample is prepared by pasting together (for example, a surface sheet coated with a gel composition). And 40 ml of simulated urine is dropped once on the surface sheet of the sample for absorbability evaluation test, and the time (seconds) when all of the simulated urine is transferred into the surface sheet is measured. Is the penetration rate (seconds). Similarly, the time (seconds) in which the simulated urine passes through the surface sheet and all moves to the absorber side is measured, and the measured time is defined as the speed of production (seconds). The simulated urine is prepared by dissolving 200 g of urea, 80 g of sodium chloride, 8 g of magnesium sulfate, 3 g of calcium chloride, and about 1 g of a pigment (blue No. 1) in 10 L of ion-exchanged water.

As in the embodiment shown in FIG. 1, the above-described gel composition extends in the longitudinal direction D _L of the absorbent article and in the width direction D _W in a plan view in a state where the absorbent article is stretched. Although it can apply to the surface by the side of the skin surface of a surface sheet with the several substantially linear coating pattern located in a line, in the absorbent article of this invention, it is not limited to this. For example, the substantially linear shape described above may be a linear shape such as a wave shape, a zigzag shape, or a dotted line shape. In the present specification, a region in which the gel composition is applied in a linear shape is referred to as a “linear coating region”. Further, the interval between the plurality of linear coating regions arranged in the width direction D _W is not particularly limited, but is 1 mm to 10 mm from the viewpoint of the above-described liquid repellency of the top sheet and the liquid permeability in the thickness direction. Is preferable, and 2 mm to 5 mm is more preferable. Each linear coating interval may be equal or different.

In addition, the direction in which each linear pattern intersects (that is, the lattice direction) is also a direction other than the longitudinal direction D _L of the absorbent article (for example, the width direction D _W ). Direction in which the coating pattern is shaped). Furthermore, even if the coating pattern of the gel-like composition is a plurality of dots extending in a predetermined region on the skin side surface of the top sheet (in this specification, the gel-like composition is A region formed in a dot shape is referred to as a “dot-shaped coating region”), and may be a geometric shape or a pattern with design. In this way, by appropriately adjusting the coating pattern of the gel-like composition, in the absorbent article, a place with high liquid repellency can be set as a desired place, or a design property can be imparted. Product design that meets various needs.

  In the absorbent article of the present invention, the means for applying the gel composition is not particularly limited, and any known application means can be employed. Examples of such coating means include an extrusion device equipped with a die or a discharge nozzle; a non-contact type coater such as a spiral coater, curtain coater, spray coater, dip coater; a contact type coater.

  About the range (namely, the ratio of the area of the coating area | region with respect to the area of the surface of the surface side of a surface sheet) where the gel-like composition on a surface sheet is applied, the area of the surface of the surface sheet of the surface sheet ( Hereinafter, the area ratio is preferably about 1% to about 50%, more preferably about 5% to about 30%, and particularly preferably about 10%. % To about 15%. When the gel-like composition is applied at an area ratio of less than 1% with respect to the area of the surface sheet, the gel-like composition has a small coating area and is hydrophobic on the skin side surface of the surface sheet. Insufficient properties make it difficult to obtain the effects of the above-mentioned liquid repellency and liquid permeability in the thickness direction, and since the amount of the gel-like composition on the top sheet is small, the gel-like composition The effect which has has cannot fully be exhibited. On the other hand, when the gel-like composition is applied at an area ratio exceeding 50% with respect to the area of the surface sheet, the area on the surface sheet where the gel-like composition is not applied (that is, non-coated). Therefore, the liquid excrement supplied on the skin side surface of the top sheet is less likely to penetrate into the top sheet.

Moreover, the coating amount of the gel-like composition applied to the skin side surface of the top sheet is usually in the range of 1 to 30 g / m ² , but preferably in the range of 6 to 15 g / m ² . More preferably, it is in the range of 6 to 10 g / m ² . When the coating amount of the gel composition is less than 6 g / m ² , the coating amount of the gel composition is small, and the hydrophobicity on the skin side surface of the surface sheet is insufficient. In addition, when the coating amount of the gel composition exceeds 15 g / m ² , the degree of being repelled by the hydrophobicity of the gel composition increases. It becomes difficult to obtain liquid permeability in the vertical direction. In addition, in this specification, the coating amount of the said gel-like composition is calculated | required as follows.
(1) A predetermined range to be measured on the surface sheet coated with the gel-like composition is cut out using, for example, a sharp blade such as a cutter blade so as not to change its thickness. Obtain a sample for quantitative measurement.
(2) The area: SA (m ² ) and mass: SM ₀ (g) of the cut sample are measured.
(3) The sample after measurement is immersed in a solvent in which a gel composition such as an aromatic solvent (for example, toluene) is soluble, and stirred for at least 3 minutes, and the gel composition is placed in the solvent. Elute.
(4) After filtering the sample in the said solvent using the filter paper which measured mass beforehand, a sample is fully wash | cleaned with a solvent on a filter paper as it is. The sample after washing is thoroughly dried in a 100 ° C. oven together with the filter paper.
(5) The mass of the filter paper and the sample after drying is measured, and the mass of the sample after drying: SM ₁ (g) is calculated by subtracting the mass of the filter paper measured in advance from the measured value.
(6) The coating amount G _BS (g / m ²⁾ of the gel composition is calculated by the following equation (1).

In addition, in order to reduce the measurement error, the coating amount of the gel composition is cut out from a plurality of absorbent articles so that the total area of the sample exceeds 100 cm ^2, and the above-mentioned for each sample. (2) perform the measurement task to (6), employing the average value of the resulting coating amount G _BS from each measuring operation.

  In addition, the gel composition may be applied when producing a material for a surface sheet such as a nonwoven fabric, or may be applied on the surface sheet in a production line for absorbent articles. From the viewpoint of suppressing capital investment, the gel composition is preferably applied on the surface sheet in the manufacturing line for absorbent articles, and in particular, from the viewpoint of suppressing contamination due to falling off of oils and the like. In the downstream process (for example, immediately before the process of individually packing the products), it is preferable to apply the coating on the surface sheet.

  Hereinafter, various components used for the absorbent article of the present invention will be described.

[Surface sheet]
In one embodiment of the present invention, the topsheet 2, the skin face side in the thickness direction D _T of the disposable diaper 1, it is disposed at the center axis on the C _L extending in the longitudinal direction D _L of the disposable diaper 1, the wearer It is a liquid-permeable sheet member that can be in direct contact with the skin surface. In the present embodiment, an air-through nonwoven fabric is used as the sheet member. However, in the absorbent article of the present invention, the sheet member is not limited to this, and any sheet conventionally known as long as it is a liquid-permeable sheet member. A member can be used. Examples of such a sheet member include a nonwoven fabric, a woven fabric, a knitted fabric, and the like, but it is preferable to use a nonwoven fabric in terms of cushioning properties, touch, versatility, and the like. In addition to the air-through nonwoven fabric described above, examples of the nonwoven fabric include a spunbond nonwoven fabric, a point bond nonwoven fabric, a spunlace nonwoven fabric, a needle punched nonwoven fabric, a melt blown nonwoven fabric, and combinations thereof (for example, SMS).

  In the absorbent article of the present invention, when a nonwoven fabric or a woven fabric is used as the surface sheet, examples of the fibers constituting the nonwoven fabric or the woven fabric include natural fibers and chemical fibers, and more specifically, pulverized pulp, Examples thereof include cellulose fibers such as cotton; regenerated cellulose such as rayon and fibril rayon; semi-synthetic cellulose such as acetate and triacetate; thermoplastic hydrophobic chemical fibers; and thermoplastic hydrophobic chemical fibers subjected to a hydrophilic treatment. Furthermore, examples of the thermoplastic hydrophobic chemical fiber include single fibers made of polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), and the like, fibers made of PE and PP graft polymers, and the like. Moreover, the above-mentioned nonwoven fabric or woven fabric may be hydrophilized after forming the nonwoven fabric or woven fabric.

As shown in FIG. 1, the topsheet 2 in the present embodiment, in plan view, but has a substantially rectangular outer shape and a long side in the longitudinal direction D _L, in the absorbent article of the present invention The shape is not limited to such a shape, and may be a rectangular shape other than a rectangular shape, or a shape that includes a curve such as an elliptical shape, an oval shape, or a saddle shape. In addition, the size of the surface sheet is not particularly limited as long as it is a size that can cover the entire surface of the skin surface side of the absorbent body arranged on the non-skin surface side of the surface sheet. Depending on the size, sex, application, etc., any size can be adopted. Furthermore, the thickness of the top sheet is not particularly limited as long as it has liquid permeability, strength, flexibility, and the like necessary for the absorbent article, and any thickness can be adopted. For example, the thickness of the surface sheet can be in the range of 0.001 mm to 5.0 mm, but preferably 0.01 mm to 3.0 mm from the viewpoint of suitable liquid permeability, cushioning properties, and touch. More preferably, it is 0.1 mm-1.0 mm.

  In the present embodiment, the topsheet 2 has a structure in which at least the surface on the skin side is flat, but the absorbent article of the present invention is not limited to such a structure. For example, as the surface sheet, a sheet having a plurality of convex portions formed on at least the skin surface side can be suitably used. When using a surface sheet having a plurality of protrusions protruding to the skin surface side, at least a part of the plurality of protrusions is coated with the above-described gel composition. It is preferable. The plurality of convex portions are portions that come into contact with the skin surface of the wearer, but when the gel-like composition is applied to such portions, the portions become hydrophobic. Since liquid excrement such as urine is prevented from remaining or returning to the liquid, it is possible to effectively prevent the discharged liquid excrement from adhering to the wearer.

Moreover, the said convex part can employ | adopt the thing of arbitrary structures according to desired liquid repellency, liquid permeability, cushioning properties, touch, etc. For example, the said convex part is a longitudinal direction of a surface sheet. It may be a ridge (projection) extending to the edge, or a flat cuboid or truncated quadrangular pyramid with rounded ridgelines, a pyramid with rounded vertices (eg, triangular pyramid, quadrangular pyramid) Etc.), or a protrusion having a three-dimensional shape such as a conical shape or a arch shape with rounded vertices. Further, the structure of the part other than the convex part is not particularly limited, and may be a groove part or a flat part. For example, in another embodiment of the present invention, the surface sheet includes the plurality of parts. The protrusions are formed as a plurality of linear ridges extending in parallel along the longitudinal direction of the surface sheet and arranged in the width direction _DW at substantially equal intervals, and a portion between two adjacent ridges is What has what is called a groove structure formed as a groove part extended along the longitudinal direction of a surface sheet, etc. are used suitably.

In embodiments where ridges and grooves extending in the longitudinal direction D linearly along the _L of the absorbent article, the liquid excrement such as urine supplied to the surface sheet, along the ridges and grooves absorption Since it becomes easy to diffuse in the longitudinal direction D _L of the absorbent article, liquid excrement is prevented from spreading in the width direction D _W of the absorbent article, and leakage of liquid excrement from the width direction D _W due to this is prevented. can do. Further, the longitudinal direction D _L liquid exudates through the topsheet while being diffused in the absorbent article, since it is possible to absorb the large area of the absorber, thereby significantly improving the absorption efficiency of the liquid excreta be able to.

  Further, in the above-described groin structure, the height of the ridge, that is, the distance between the horizontal plane including the top of the ridge and the horizontal plane including the bottom of the groove is liquid excretion such as urine supplied on the top sheet. When the object can be guided in a predetermined direction and the buttocks contact the wearer's skin, it is usually in the range of 0.1 to 1.2 mm from the viewpoint that the wearer does not feel uncomfortable or uncomfortable. Preferably, it exists in the range of 0.2 mm-1.0 mm, More preferably, it exists in the range of 0.4 mm-0.8 mm. The height of the buttock is determined using a laser displacement meter (for example, a high-precision two-dimensional laser displacement meter LJ-G series (model: LJ-G030) manufactured by Keyence Corporation) as follows. Can be measured. A sample of the surface sheet cut out to a size of 100 mm × 100 mm was placed on a horizontal measurement table, and the displacement from the measurement table was measured with a laser displacement meter for five different flanges, and the average of the five measurement values was measured. The value is the thickness (mm) of the buttocks. Similarly, about five different groove parts, the displacement from a measurement stand is measured with a laser displacement meter, and let the average value of five measured values be the thickness (mm) of a groove part. From the difference between the thickness (mm) of the flange and the thickness (mm) of the groove, the height (mm) of the flange is calculated.

  Furthermore, as for the width of the ridge and the groove of the above-described ridge groove structure, the width of the ridge can be usually within a range of 1.0 to 5.0 mm, but the diffusibility of liquid excreta It is preferably 2.0 to 4.0 mm from the viewpoints of liquid repellency, cushioning properties, and touch. In addition, when the width | variety of a buttocks exceeds 5.0 mm, liquid excretion will remain easily in a buttocks and there exists a possibility that liquid spillability may fall. Similarly, the width of the groove can be usually in the range of 1.0 to 3.0 mm, preferably 1.0 to 2.0 mm. In addition, the pitch of the ridge groove structure (that is, the distance between the top centers of two adjacent ridges (mm)) can be in the range of 2.0 mm to 8.0 mm, but the liquid excrement is diffused. The thickness is preferably 2.0 mm to 6.0 mm from the viewpoints of properties, liquid repellency, cushioning properties, and touch. In addition, the width | variety of a collar part is the distance between the boundary lines between a collar part and two groove parts located in the both sides of this collar part based on the plane photograph or plane image of a surface sheet in a non-pressurized state. Can be measured as The width of the groove is the same.

In the absorbent article of the present invention, the groove structure that can be adopted as the structure of the surface sheet is not limited to the above-described embodiment. For example, the groove part and the groove part of the groove structure are at least partially the length of the absorbent article. A mode extending in a direction other than the direction D _L (for example, the width direction D _W of the absorbent article), a mode extending at least partially while changing the direction (for example, a wave shape or a zigzag shape), at least a portion A mode in which the absorbent article extends discontinuously (that is, intermittently) in the longitudinal direction D _L of the absorbent article, a mode in which the distance between two at least partially adjacent ribs is not constant, It can be set as the aspect which combined two or more arbitrarily. In this way, by appropriately setting the extending direction and form of the buttock and groove, it is possible to control the diffusion direction of the liquid excrement supplied on the top sheet, and the product design that meets various needs Can be realized.

  The method for forming the above-described grooved structure on the top sheet is not particularly limited, and is disclosed in, for example, Japanese Patent Application Laid-Open Nos. 2008-25079, 2008-23326, and 2009-30218. As described above, a method of forming a groove structure by continuously blowing gas (usually air) on a fiber web, a method using vacuum forming, a method using gear stretching, and thermal stretching of a thermally stretchable fiber And / or well-known methods, such as the method of utilizing the heat shrink of a heat-shrinkable fiber, are employable.

  When using a surface sheet having such a ridge groove structure, the gel-like composition described above is linear along the ridge portion in at least some of the ridge portions of the plurality of ridge portions. It is preferable that it exists as a coating area | region or a dotted | punctate coating area | region. The plurality of buttocks are portions that come into contact with the skin surface of the wearer, and when the above-described gel composition is applied to such a portion, the portion becomes hydrophobic. The liquid excrement such as urine remains or returns from the liquid, so that the excretion of the excreted liquid excrement can be effectively prevented from adhering to the wearer. The above-described effects produced by having the liquid excretion, that is, the effect of significantly improving the absorption efficiency of the liquid excrement can be enjoyed while preventing leakage of the liquid excrement.

In the absorbent article of the present invention, the basis weight of the topsheet is not particularly limited, and any basis weight can be adopted as long as liquid permeability, strength, flexibility and the like are not impaired. Such basis weight, for example, be a ^{10g / m 2 ~100g / m 2} , preferably ^{20g / m 2 ~50g / m 2} . If the basis weight is less than 10 g / m ² , the surface strength as a surface sheet cannot be sufficiently obtained, and there is a possibility of tearing during wearing of the absorbent article. Moreover, when this basic weight exceeds 100 g / m < ² >, excessive wrinkle will arise and there exists a possibility of causing discomfort, a discomfort, etc. to the wearer of an absorbent article.

[Absorber]
In the disposable diaper 1 of the present embodiment, the absorber 4 is disposed on the non-skin surface side of the top sheet 2 and absorbs and holds liquid excrement such as urine that has passed through the top sheet 2. In general, the absorbent body is preferably bulky, less likely to lose its shape, and less chemically stimulated in consideration of water absorption and comfort during wearing. From such a point, the absorbent body 4 includes an absorbent core 41 for absorbing and holding liquid excrement and a core wrap sheet 42 surrounding the absorbent core 41 as shown in FIG. It is done. In the present embodiment, the topsheet 3 disposed on the skin surface side of the absorbent body 4 and the core wrap sheet 42 are at least partially joined by an arbitrary adhesive such as a hot-melt adhesive.

  Examples of the absorbent core include fiber materials such as fluff pulp, spunbond nonwoven fabric, airlaid nonwoven fabric, cellulosic fibers, and the like, and hydrophilic fibers such as thermoplastic fibers, and superabsorbents such as sodium acrylate copolymer. The thing containing a polymer etc. are mentioned. In addition, the absorption core does not need to contain the superabsorbent polymer, For example, what surrounded only the above-mentioned fiber material with the core wrap sheet | seat can also be used as an absorber.

The core wrap sheet has liquid permeability that allows liquid excretion such as urine to permeate, and does not permeate the components of the absorbent core that is contained (that is, the fiber material constituting the absorbent core does not leak). Although it is not particularly limited as long as it has a degree of barrier properties, examples thereof include sheet-like fiber structures such as nonwoven fabrics, woven fabrics, and knitted fabrics made of natural fibers and chemical fibers. Includes a tissue having a basis weight of about 10 g / m ² to about 30 g / m ² , a liquid-permeable nonwoven fabric, a hydrophilic nonwoven fabric, and the like.

  In the absorbent article of the present invention, the structure of the absorbent body is not particularly limited, and an arbitrary structure can be adopted according to the desired absorption performance, size, application, and the like.

[Back sheet]
In the absorbent article of the present invention, the liquid-impermeable back sheet is not particularly limited, and any conventionally known sheet member can be used. As such a sheet member, for example, a film containing PE, PP, etc., a resin film having air permeability, a laminate in which a resin film having air permeability is bonded to a nonwoven fabric such as spunbond or spunlace, SMS, etc. A multilayer nonwoven fabric etc. are mentioned.

  Moreover, the absorbent article of this invention can further contain arbitrary structural members according to a desired product characteristic, a use, etc. The present invention can be applied to various absorbent articles such as an incontinence pad, a sanitary napkin, and a panty liner, in addition to the disposable diaper of the above-described embodiment. Moreover, the absorbent article of the present invention is not limited to the above-described embodiment and the like, and can be appropriately changed within the scope not departing from the object and spirit of the present invention.

  Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited only to the examples.

Example 1
On a surface sheet made of a nonwoven fabric having a grooved structure with a pitch of 3 mm, 5% by mass of polystyrene-block-poly (ethylene-co-butylene) -block-polystyrene (SEBS) and polystyrene-block-polyethylene-block-poly By copolymerizing 2% by mass of (ethylene-co-propylene) -block-polystyrene (SEPS) and Pearl Ream 6 (manufactured by NOF Corporation, liquid isoparaffin, isobutene and n-butene, and then adding hydrogen A gel-like composition comprising 90% by mass of the branched-chain hydrocarbon produced, degree of polymerization: about 5 to about 10, weight average molecular weight: about 330) and 3% by mass of silicone oil (100 cst) is applied. Surface sheet sample coated with a width of 2 mm and a coating interval of 2 mm and having a plurality of linear coating regions Was made. The created surface sheet sample was bonded to the part of the baby paper diaper, Mooney “Air Fit” S size, which is commercially available from Unicharm Corporation, using a hot melt adhesive. The absorbent article of Example 1 was produced.

Comparative Example 1
An absorbent article of Comparative Example 1 was produced in the same manner as Example 1 except that the gel-like composition was not coated on the above surface sheet.

  About the absorptive article of Example 1 and comparative example 1, the speed of penetration, penetration rate, rewet amount, and joint strength with a core wrap sheet were measured in the following ways. The measured values are shown in Table 1.

  The permeation rate is determined by measuring the time (seconds) in which 40 ml of simulated urine is dropped once on the surface sheet of each absorbent article, and all of the simulated urine has moved into the surface sheet. The permeation rate (second) was used. Similarly, the burning speed was measured by measuring the time (seconds) when the simulated urine passed through the surface sheet and moved all to the absorber side, and the measured time was defined as the burning speed (seconds). The measurement of the speed of penetration and the rate of penetration was carried out three times in succession. The simulated urine was prepared by dissolving 200 g of urea, 80 g of sodium chloride, 8 g of magnesium sulfate, 3 g of calcium chloride, and about 1 g of a dye (blue No. 1) in 10 L of ion-exchanged water.

About each absorbent article of Example 1 and Comparative Example 1, the rewetting amount (g) was measured by the following test method.
(1) Mark the simulated urine dropping position of the sample.
(2) Measure the weight of the sample and the thickness of the simulated urine dropping position. A thickness meter (PEACOCK PIALTHICKNESS GAUGE, diameter 50 mm) is used for measuring the thickness.
(3) Fix the sample.
(4) Fix the burette at a position 10 mm above the simulated urine dropping position.
(5) Remove the burette and place a cylinder (diameter 60 mm, weight 200 g) on the sample so that the mark of the simulated urine dropping position is located at the center.
(6) The burette is returned to the simulated urine dropping position (center of the cylinder), and the first simulated urine dropping is started (T = 0).
(7) 70 mL of simulated urine is dropped.
(8) Wait until the simulated urine disappears from the surface of the top sheet in the cylinder.
(9) The weight (g) of the filter paper (Advantech No. 2,100 mm × 100 mm) is measured, and this is designated as “weight A (g)”.
(10) Five minutes after the start of the simulated urine dripping (T = 5 minutes), the weight-measured filter paper (Advantech No. 2,100 mm × 100 mm) is sampled so that the center of the filter paper coincides with the simulated urine dripping position. Install it on top and place a weight (3.5 kg) on it.
(11) Eight minutes after the start of dripping the simulated urine (T = 8 minutes) (three minutes after the weight was set), the weight was removed, and the weight (g) of the filter paper was measured. ) ”.
(12) The amount of change in the weight of the filter paper (weight B (g) −weight A (g)) is calculated, and this is defined as “first rewet amount (g)”.
(13) The second simulated urine dripping is started 10 minutes after the start of the first simulated urine dripping (T = 10 minutes).
(14) Drip 70 mL of simulated urine.
(15) Similarly to the above (8) to (12), in the cylinder, wait until the simulated urine disappears from the surface of the top sheet, calculate the amount of change (g) in the weight of the filter paper, Rewetting amount (g) ”.
(16) The third simulated urine dropping is started 10 minutes after the start of the second simulated urine dropping (T = 20 minutes).
(17) Drip 70 mL of simulated urine.
(18) Similarly to the above (8) to (12), in the cylinder, wait until the simulated urine disappears from the surface of the top sheet, and calculate the amount of change (g) in the weight of the filter paper. Amount (g) ".
(19) The measurement of the first to third rewet amounts is repeated five times, and the average value thereof is calculated.

About each absorbent article of Example 1 and Comparative Example 1, the bonding strength between the top sheet and the core wrap sheet was measured by the following test method.
i) From each absorbent article, the surface sheet and the core wrap sheet bonded to the surface sheet are taken out and cut to a width of 25 mm to prepare a sample for a tensile test.
ii) The longitudinal ends of the top sheet and core wrap sheet of the sample for tensile test are sandwiched between chucks (distance between chucks: 10 mm) of a tensile tester.
iii) Using a tensile tester, the surface sheet and the core wrap sheet of the sample for tensile test are pulled so as to peel in a 180 ° direction, and the load value is measured.
iv) The maximum value of the measured load value is defined as the joint strength (N / 25mm).

As shown in Table 1, while the absorbent article of Example 1 maintained the penetration rate equivalent to the absorbent article of Comparative Example 1 in which the gel composition was not applied, It was found that the peach was superior to the absorbent article of Comparative Example 1. In addition, the absorbent article of Comparative Example 1 has a bonding strength of about 10% lower after one week at 50 ° C., whereas the absorbent article of Example 1 has passed one week at 50 ° C. However, it has been found that the bonding strength does not decrease.
The present invention includes the following aspects.
One embodiment (embodiment 1) of the present invention is an absorbent body including an absorbent core and a core wrap sheet surrounding the absorbent core, disposed on the skin surface side of the absorbent body, and bonded to the core wrap sheet with an adhesive. The surface sheet has a longitudinal direction, a width direction, and a thickness direction, and maintains a gel state at 38 ° C. on the skin surface side of the surface sheet. It is the said absorbent article in which the hydrophobic gel-like composition which can be applied is intermittently applied.
Moreover, in another aspect (aspect 2) of this invention, in the absorbent article of the said aspect 1, the said surface sheet has a some convex part which protrudes on the skin surface side, Of these convex parts, The gel composition is applied to at least some of the convex portions.
Furthermore, in another aspect (aspect 3) of the present invention, in the absorbent article according to aspect 2, the plurality of convex portions are a plurality of flanges extending in the longitudinal direction of the surface sheet, and the surface sheet is The gel-like composition has a ridge groove structure including a plurality of ridges and a plurality of groove portions existing between the ridge portions, and the gel composition is a line in at least some of the ridge portions. It exists as a strip-shaped coating region or a spot-shaped coating region.
Furthermore, in another aspect (aspect 4) of the present invention, in the absorbent article according to aspect 3, the pitch of the groove structure is 2.0 mm to 5.0 mm.
Furthermore, in another aspect (aspect 5) of the present invention, in the absorbent article according to aspect 4, the gel-like composition is parallel to the longitudinal direction of the surface sheet on the skin surface side of the surface sheet. It exists as several linear coating area | regions extended, and the space | interval of the said linear coating area | region is 1-10 mm.
Furthermore, in another aspect (aspect 6) of the present invention, in the absorbent article according to any one of the aspects 1 to 5, the gel composition is composed of a composition containing a styrene elastomer and a hydrocarbon oil.
Furthermore, in another aspect (aspect 7) of the present invention, in the absorbent article according to aspect 6, the gel-like composition has a weight average molecular weight of 100,000 or more and less than 180,000, and a block of triblock or more. A styrene thermoplastic elastomer (A1) made of a polymer and a styrene thermoplastic elastomer (A2) made of a block copolymer having a weight average molecular weight of 180,000 to 300,000 and a triblock or more ( A1) / (A2) = Styrenic thermoplastic elastomer mixture (A) containing at a mass ratio of 95/5 to 50/50 and having a molecular weight dispersity (Mw / Mn) of 1.25 to 1.60 The hydrocarbon oil (B) having a kinematic viscosity at 37.8 ° C. of 5 to 50 mm ² / s with respect to 100 parts by mass of 500 to 4800 parts by mass and the kinematic viscosity at 25 ° C. of 50 to 200 mm ^It consists of a composition containing 20-60 mass parts of silicone oil (C) which is ² / s.

DESCRIPTION OF SYMBOLS 1 Disposable diaper 2 Top sheet 3 Back sheet 4 Absorber 41 Absorbing core 42 Core wrap sheet 5 Side sheet member 6 Coating area

Claims (7)

An absorbent article comprising: an absorbent body including an absorbent core and a core wrap sheet surrounding the absorbent core; and a surface sheet disposed on a skin surface side of the absorbent body and bonded to the core wrap sheet by an adhesive. There,
The top sheet has a longitudinal direction, a width direction and a thickness direction,
A hydrophobic gel-like composition that can maintain a gel state at 38 ° C. and contains hydrocarbon oil is intermittently applied to the skin side surface of the topsheet,
The top sheet is composed of hydrophilic fibers, and the inside of the top sheet has hydrophilicity,
The gel composition may have a mesh-like network structure,
The absorptive article , wherein the network-like network structure is formed of a styrene-based elastomer, and the styrene-based elastomer is a triblock or higher block copolymer including a polystyrene-based hard segment and a soft segment .   The absorbent article according to claim 1, wherein the gel composition releases the hydrocarbon oil gradually.   The absorbent article according to claim 1 or 2, wherein the hydrocarbon oil is held in the network-like network structure.   The surface sheet has a plurality of protrusions protruding toward the skin surface side, and the gel composition is coated on at least some of the plurality of protrusions. The absorbent article as described in any one of -3.   The plurality of convex portions are a plurality of ridges extending in the longitudinal direction of the top sheet, and the top sheet is a ridge groove structure comprising the plurality of ridges and a plurality of groove portions existing between the ridge portions. The absorption according to claim 4, wherein the gel composition is present as a linear coating region or a dotted coating region in at least some of the plurality of collars. Sex goods.   The absorptive article according to claim 5 whose pitch of said slot structure is 2.0 mm-5.0 mm.   The gel composition is present as a plurality of linear coating regions extending in parallel with the longitudinal direction of the surface sheet on the skin side surface of the surface sheet, and the spacing between the linear coating regions is The absorptive article according to claim 6 which is 1-10 mm.

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