KR20170016837A - Absorbent article - Google Patents

Abstract

An object of the present invention is to provide an absorbent article having a gel composition with a low tackiness on its surface while having suitable hardness, elongation, and sustained releasing property of the active ingredient. The absorbent article (1) of the present invention comprises a gel composition on the skin surface side of the topsheet (2), the gel composition comprising a low molecular weight styrenic thermoplastic elastomer (A1) and a high molecular weight styrenic thermoplastic A styrenic thermoplastic elastomer mixture (A) having an elastomer (A2) in a mass ratio of (A1) / (A2) of 95/5 to 50/50 and having a molecular weight distribution (Mw / Mn) of 1.25 to 1.60 , 500 to 4800 parts by mass of a hydrocarbon oil (B) having a kinematic viscosity (kinematic viscosity) of 5 to 50 mm 2 / s at 37.8 ° C. and 500 to 4800 parts by mass of a silicone having a dynamic viscosity at 50 ° C. of 50 to 200 mm 2 / And 20 to 60 parts by mass of the oil (C).

Description

[0001] ABSORBENT ARTICLE [0002]

The present invention relates to an absorbent article comprising a gel composition having a small tack, having a suitable hardness, elongation, and sustained releasability of an active ingredient on its surface. The present invention also relates to a nonwoven fabric having a gel composition having a low tackiness and having a suitable hardness, elongation, and sustained release of an effective component.

In absorbent articles such as sanitary napkins, panty liners, diapers and the like, the basic performance such as absorption performance is improved by long-accumulated technology development, so that compared to the past, leakage or the like occurs after absorbing excretion such as menstrual blood or urine And there is a demand for more sophisticated functions such as a feeling of fit close to underwear, excellent flexibility and cushioning, and the like.

For example, Patent Document 1 discloses an absorbent article comprising an effective amount of a lotion coating capable of being transferred to at least part of the outer surface of the topsheet at 20 DEG C, semi-solid or solid and partly to the wearer's skin. Further, according to Patent Document 1, the lotion coating comprises: (i) 10 to 95% of the emulsion having a plasticity or fluidity consistency at 20 DEG C and having an oil-based emollient agent, a fatty acid ester emollient agent, an alkyl ethoxylate emollient agent, And mixtures thereof, (ii) from 5 to 90% of the emollient agent is an immobilizing agent that allows immobilizing the emollient agent on the outer surface of the topsheet , At least 35 캜, preferably at least 40 캜, and is selected from the group consisting of polyhydroxy fatty acid esters, polyhydroxy fatty acid amides, C ₁₄ -C ₂₂ fatty alcohols, C ₁₂ -C ₂₂ fatty acids, C ₁₂ -C ₂₂ fatty alcohols Ethoxylate, and a mixture thereof.

Patent document 2 discloses an absorbent article comprising a liquid permeable top sheet, a liquid impermeable or water repellent back sheet and an absorbent body disposed between the both, wherein the top sheet has a high density portion and a low density portion, Wherein the high density portion and the low density portion are distributed in a plane direction of the topsheet, and the skin care agent is applied to the low density portion in a larger amount than the high density portion. Also, in paragraph [0069] of Patent Document 2, a skin care agent containing a diamide derivative of an active ingredient and stearyl alcohol in a mass ratio of 5: 5 is disclosed.

The absorbent article of Patent Document 1 has an action of immobilizing the lotion coating by increasing the viscosity of the lotion coating and crystallizing the immobilizing material having a melting point of 35 ° C or higher at room temperature (25 ° C) in the lotion coating . In addition, in the absorbent article of Patent Document 2, since the added stearyl alcohol has a melting point of 58 캜, it is presumed that the absorbent article has an action of immobilizing the skin care agent like the absorbent article of Patent Document 1.

When the lotion coating or the skin care agent is made highly viscous, the active ingredient is trapped in the inside thereof, and the release of the effective ingredient is suppressed more than necessary. Thus, satisfactory release of the active ingredient is obtained . In addition, the lotion coating or skin care agent having a high viscosity may be poor in wearing feeling because the material applied to the topsheet of the absorbent article (i.e., the material directly contacting the skin) is insufficient in flexibility and elongation.

On the other hand, Patent Document 3 discloses a gel composition showing delayed elasticity against hardness, elongation, etc. of gel. This composition is a gel elastomer comprising a high molecular weight triblock styrenic thermoplastic elastomer having a number average molecular weight of 130,000 or more and a low molecular weight triblock styrenic thermoplastic elastomer having a number average molecular weight of 100,000 or less and a softening agent, The triblock type styrene type elastomer having a molecular weight absorbs and retains a large amount of the softening agent to secure the flexibility of the composition and to impart delayed elasticity by containing a low molecular weight triblock type styrene type elastomer. It was still insufficient with respect to the tacticity and the Sino-Japanese castle.

Japanese Patent Publication No. Hei 10-509896 Japanese Patent Laid-Open No. 2011-131044 Japanese Patent Application Laid-Open No. 2001-151980

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an absorbent article comprising a gel composition having a suitable hardness, elongation, and sustained release of an active ingredient and having less tackiness. It is also an object of the present invention to provide a nonwoven fabric having a gel composition having a suitable degree of hardness, elongation and sustained release of an active ingredient and having a low tackiness on its surface.

The present invention relates to an absorbent article having a liquid permeable top sheet, a liquid impermeable back sheet, and an absorbent body positioned between the top sheet and the back sheet, wherein the top sheet has a gel composition Wherein the gel composition comprises a styrenic thermoplastic elastomer (A1) having a weight average molecular weight of 100,000 or more and less than 180,000, and further comprising a block copolymer having a triblock or more block structure, and a styrene-based thermoplastic elastomer (A1) / (A2) = 95/5 to 50/50, and the molecular weight distribution (Mw / Mn) of the styrene thermoplastic elastomer (A2) (B) having a kinematic viscosity (kinematic viscosity) of 5 to 50 mm < 2 > / s at 37.8 [deg.] Relative to 100 parts by mass of the styrene thermoplastic elastomer mixture (A) RTI ID = 0.0 > mm / s < / RTI > One (C) to contain parts of 20 to 60 wt.

According to the present invention, there is provided an absorbent article comprising a gel composition having an appropriate hardness, elongation, and sustained release of an active ingredient and having a low tackiness on the surface.

1 is a plan view showing an absorbent article according to one embodiment of the present invention.
2 is a plan view showing an absorbent article according to another embodiment of the present invention.

The absorbent article of the present invention will be described in detail below.

The absorbent article of the present invention comprises at least a liquid permeable top sheet positioned on the skin surface side of the wearer, a liquid impervious back sheet positioned on the garment side (i.e., the side opposite to the wearer's skin surface side) And a laminate structure having an absorber positioned between the backsheet, wherein the topsheet comprises a gel composition on a surface of the skin surface side.

[Gel composition]

In the present invention, the gel composition preferably comprises a styrenic thermoplastic elastomer (A1) having a weight average molecular weight of 100,000 or more and less than 180,000, and further comprising a block copolymer having a triblock or more block copolymer and a styrene- (A1) / (A2) = 95/5 to 50/50, and the molecular weight distribution (Mw / Mn) of the styrene thermoplastic elastomer (A2) (B) having a kinematic viscosity of 5 to 50 mm < 2 > / s at 37.8 [deg.] C with respect to 100 parts by mass of the styrene-based thermoplastic elastomer mixture (A) And 20 to 60 parts by mass of a silicone oil (C) having a kinetic viscosity of 50 to 200 mm < 2 > / s.

The styrenic thermoplastic elastomer (A1, A2) used in the gel-like composition is a block copolymer of a triblock or more including a polystyrene-based hard segment and a soft segment, preferably a block copolymer composed of a styrene- And more preferably a block copolymer having a block component composed of the styrene hard segment at least at both ends in the molecular chain. Examples of the polystyrene hard segment include, but are not limited to, polystyrene such as polystyrene, poly (? -Methylstyrene), poly (o-methylstyrene), poly (m- Based polymer. 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 styrenic thermoplastic elastomer (A1, A2) is not particularly limited as long as it is a styrenic block copolymer having a triblock or more. Examples thereof include styrene-butadiene-styrene block copolymer (SBS), styrene- Butene-styrene block copolymer (SEBS), styrene-isoprene-styrene block copolymer (SIS), styrene-ethylene-propylene-styrene block copolymer (SEPS) , Styrene-ethylene-ethylene-propylene-styrene block copolymer (SEEPS), and combinations of two or more thereof. Of these, styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-ethylene-propylene-styrene block copolymer (SEPS) and styrene-ethylene / Ethylene-propylene-styrene block copolymer (SEEPS). In the case of using a diblock copolymer as the styrene-type thermoplastic elastomer (A1, A2), the interaction (π-π stacking) of the styrene hard segment is weakened, . On the other hand, in the styrene-based thermoplastic elastomer, a network structure of a mesh type is formed by a plurality of aggregation domains formed by the interaction of the styrene hard segment and an olefin-based soft segment connecting the plurality of aggregation domains , And is considered to exhibit a function as an elastic body. It is also believed that such a network structure of the network has a function of keeping the oil agent (that is, the hydrocarbon oil (B) and the silicone oil (C)) to be described later while appropriately releasing it.

The block copolymer preferably contains 10 to 50 mass% of a styrenic block component and about 50 to 90 mass% of an olefinic block component, more preferably 15 to 40 mass% of a styrenic block component and 60 to 85 Particularly preferably 18 to 35 mass% of a styrene block component and 65 to 82 mass% of an olefin block component. If the amount of the styrenic block component is less than 10% by mass, the amount of the styrenic block component forming the coagulation domain becomes small, and it becomes difficult for the styrenic thermoplastic elastomer to form the network structure of the above-mentioned network. On the other hand, when the amount of the styrenic block component exceeds 50% by mass, the amount of the olefin-based block component that retains the emulsions and the like becomes small, The amount of agglomerated domains formed by the segments increases, so that the gel after application to the topsheet becomes hard and the feeling of wearing may be poor.

In the present invention, the styrene-based thermoplastic elastomer mixture (A) is a mixture of two kinds of styrene-based thermoplastic elastomers (A1, A2) having different weight average molecular weights.

One styrene thermoplastic elastomer (A1) (hereinafter sometimes referred to as "low molecular weight styrene thermoplastic elastomer (A1)") among the two styrene thermoplastic elastomers (A1, A2) The molecular weight is in the range of 100,000 or more and less than 180,000, and preferably in the range of 100,000 to 150,000. When the weight average molecular weight is less than 100,000, the hardness and elongation of the gel after application to the topsheet are lowered. The styrene type thermoplastic elastomer (A2) (hereinafter sometimes referred to as " high molecular weight styrene type thermoplastic elastomer (A2) ") may have a weight average molecular weight of 180,000 or more and 300,000 or less , And preferably in the range of 220,000 to 280,000. If the weight average molecular weight exceeds 30,000, toughness tends to occur on the surface of the gel.

The styrene thermoplastic elastomer mixture (A) preferably has a degree of dispersion (i.e., a ratio (Mw / Mn) of weight average molecular weight (Mw) to number average molecular weight (Mn)) of 1.25 to 1.60, preferably 1.35 To 1.55. If the dispersion degree is less than 1.25, the physical properties of the gel-like composition are not different from those in the case of using a single styrenic thermoplastic elastomer, so that the elongation of the gel after application to the topsheet becomes insufficient. On the other hand, if the dispersion degree exceeds 1.60, the gel after application to the top sheet becomes heterogeneous due to the difference in cooling and solidifying time between the two kinds of styrene-based thermoplastic elastomers (A1, A2) And the like.

The weight average molecular weight (Mw) of the two styrenic thermoplastic elastomers (A1 and A2) and the styrenic thermoplastic elastomer mixture (A) and the degree of dispersion (Mw / Mn) of the styrenic thermoplastic elastomer mixture (A) , Tetrahydrofuran (THF) as a mobile phase (mobile phase), and performing GPC measurement under the following conditions to obtain polystyrene equivalent.

[Conditions for measuring GPC]

Device : GPC-8220 (manufactured by Tosoh Corporation)

column : SHODEX KF-804 (manufactured by Showa Denko K.K.)

Temperature : 40 ° C

menstruum : THF

flux : 1.0 mL / min

Sample concentration : 0.05 to 0.6 mass%

Dose : 0.1 mL

detection : RI (differential refractometer)

As described above, in the present invention, the gel-like composition contains a mixture of two styrenic thermoplastic elastomers (A1, A2) having different weight average molecular weights, and the blending amount thereof is not particularly limited as long as the styrene thermoplastic elastomer (A1) / (A2) = 95/5 to 50/50, preferably 90/10 to 60/40, and more preferably in a weight ratio of the high molecular weight styrene-based thermoplastic elastomer (A1) It is 80/20 to 70/30. If the compounding ratio of the styrene thermoplastic elastomer (A1) having a low molecular weight in the above mass ratio exceeds 95, the hardness and elongation of the gel after application to the top sheet become insufficient, and if the mixing ratio is less than 50, Tending to occur easily.

In the present invention, the gel composition further comprises a hydrocarbon oil (B) having a kinematic viscosity at 37.8 DEG C of 5 to 50 mm < 2 > / s. The hydrocarbon oil (B) is not particularly limited as long as it is a compound comprising 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 not containing double bonds and triple bonds), acetylene hydrocarbons ), Hydrocarbons containing 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, squalane and the like can be mentioned. In particular, the hydrogenated polyisobutene can be obtained by a method in which the gel after application to the topsheet does not develop tackiness, And stickiness is not generated, so that it can be preferably used.

The hydrocarbon oil (B) has a kinematic viscosity at 37.8 캜 in the range of 5 to 50 mm 2 / s, preferably in the range of 10 to 30 mm 2 / s, more preferably in the range of 10 to 20 mm 2 / s It is mine. If the kinematic viscosity is less than 5 mm 2 / s, the hydrocarbon oil (B) tends to be volatilized during the production of the gel-like composition, so that the physical properties of the gel after application to the topsheet may fluctuate. On the other hand, if the kinematic viscosity exceeds 50 mm 2 / s, the gel after application to the topsheet becomes hard, and toughness tends to occur. On the other hand, the kinematic viscosity of the hydrocarbon oil (B) is determined in accordance with JIS K 2283: 2000 " 5. Kinematic viscosity test method ", using a Canon Pen Scale backflow viscometer at a test temperature of 37.8 캜.

The blending amount of the hydrocarbon oil (B) is in the range of 500 to 4800 parts by mass, preferably in the range of 800 to 3000 parts by mass, more preferably in the range of 1000 to 1000 parts by mass, relative to 100 parts by mass of the styrene-based thermoplastic elastomer mixture (A) To 1500 parts by mass. When the blending amount is less than 500 parts by mass, the gel after application to the topsheet becomes hard and the elongation also decreases. On the other hand, when the blending amount exceeds 4800 parts by mass, the gel becomes too soft and it becomes difficult to maintain the shape of the gel.

In the present invention, the gel composition further comprises a silicone oil (C) having a kinematic viscosity at 25 DEG 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. Particularly, dimethylpolysiloxane can be suitably used because it can impart an appropriate sustained-release property such as an emulsion to the gel-like composition.

The silicone oil (C) has a kinematic viscosity at 25 캜 in the range of 50 to 200 mm 2 / s, preferably in the range of 70 to 150 mm 2 / s, more preferably in the range of 80 to 120 mm 2 / s It is mine. If the kinematic viscosity is less than 50 mm < 2 > / s, the silicone oil (C) tends to be volatilized during the production of the gel-like composition, so that the physical properties of the gel after application to the topsheet may fluctuate. On the other hand, when the kinematic viscosity exceeds 200 mm < 2 > / s, the sustained release amount of the emulsion or the like becomes small and the selectivity tends to occur. On the other hand, regarding the kinematic viscosity of the silicone oil (C), the " 5. Kinematic viscosity test method ", using a Canon Pen Scale backflow viscometer at 25 占 폚.

The blending amount of the silicone oil (C) is within a range of 20 to 60 parts by mass, preferably 30 to 50 parts by mass, based on 100 parts by mass of the styrene-based thermoplastic elastomer mixture (A). When the blending amount is less than 20 parts by mass, the amount of the esters such as an emulsion is reduced. On the other hand, if the blending amount exceeds 60 parts by mass, the amount of the esters such as the emulsions becomes excessively large, and the surface of the gel becomes fertile.

In the present invention, the gel-type composition may contain a stabilizer, an antioxidant such as BHT (2,6-di-t-butyl-p-cresol), BHA (butylated hydroxyanisole) (Such as alumina, talc, mica, calcium carbonate, and clay), organic powders (such as powders of PE, PP, and silicone resin), coloring agents, pigments (such as titanium oxide and zinc oxide) , And the like, or other components in the range of not deteriorating the object of the present invention.

Examples of the other components include oils having a skin-care action (such as jojoba oil and camellia oil), vitamins, various amino acids, peptides, zeolites, cholesterol, hyaluronic acid, lecithin, ceramides, skin astringents, Anti-wrinkle agents, anti-cellulite agents, whitening agents, antibacterial agents, anti-fungal agents, anti-inflammatory agents, pH adjusting agents and humectants.

The gel-like composition can be produced by mixing the various components described above by using any known mixing means. For example, the gel-like composition can be produced by feeding the above-mentioned various ingredients in a mixing device at the same time or in an arbitrary order, and melt-mixing them in the mixing device. The melt mixing means is not particularly limited and any known means may be employed. For example, the melt mixing means may be a single screw extruder, a twin screw extruder, a roll, a Banbury mixer, various kneaders, .

In addition to having appropriate hardness and elongation, the gel-like composition also has sustained release properties, so that the gel-like composition can be coated or molded while suppressing adhesion to various coating or molding apparatuses. Further, since the gel composition contains a large amount of styrene-based thermoplastic elastomer having a lower molecular weight than that of a high molecular weight styrene-based thermoplastic elastomer, it exhibits appropriate fluidity even at a temperature of around 100 ° C., , Olefin resin, PET resin and the like can be easily laminated or integrally formed by coating or the like.

1 is a plan view showing an absorbent article (sanitary napkin) according to one embodiment of the present invention. The sanitary napkin 1 shown in Fig. 1 comprises a liquid-permeable top sheet 2 positioned on the wearer's skin side and a liquid impermeable backsheet 2 positioned on the wear side (i.e., opposite to the skin surface side) And an absorbent body 3 positioned between the topsheet 2 and the backsheet. In the sanitary napkin 1 shown in Fig. 1, a side sheet 4 and an embossed portion 5 are provided.

The topsheet 2 includes a plurality of ridge-like gel compositions 6 coated on the skin surface side in parallel with one another along the longitudinal direction of the sanitary napkin 1. On the other hand, in the absorbent article of the present invention, the coating pattern of the gel-like composition is not limited thereto.

2 is a plan view showing an absorbent article (sanitary napkin) according to another embodiment of the present invention. The sanitary napkin 1 shown in Fig. 2 includes a plurality of dot-shaped gel-like compositions 6 coated on the skin surface side of the topsheet 2 in a zigzag pattern.

It is preferable that the gel composition is coated at an area ratio of 1 to 50% of the area of the area where the top sheet and the absorber overlap in a plan view, and is coated at an area ratio of 3 to 40% , And it is particularly preferable that the coating is carried out at an area ratio of 5 to 30% of the area. If the gel composition is coated with an area ratio of less than 1% of the above region, the effect of the gel composition can not be sufficiently exhibited because the amount of the gel composition on the topsheet is small. On the other hand, if the gel composition is coated at an area ratio exceeding 50% of the area, since the area on the top sheet coated with the gel composition does not absorb the excrement, There is a possibility that the absorption capacity of the absorbent article is lowered.

The top sheet coated with the gel composition has a content of the gel composition of preferably 1 to 30 g / m 2, more preferably 2 to 20 g / m 2, particularly preferably 3 to 10 g / m 2 . On the other hand, in the present specification, the content of the gel composition is determined as follows.

(1) A predetermined range to be measured of the top sheet coated with the gel-like composition is cut out with a sharp blade such as a razor blade of a cutter so as not to change its thickness to obtain a sample for measuring the content.

(2) The area of the cut sample: SA (m 2) and the mass: SM ₀ (g) are measured.

(3) The sample after measurement is immersed in a solvent which is soluble in a gel-type composition such as an aromatic solvent (e.g., xylene) and stirred for at least 3 minutes to elute the gel-like composition into a solvent.

(4) A sample in the solvent is filtered using a filter paper having a mass measured in advance, and then the sample is thoroughly washed with a solvent on a filter paper. The washed sample is thoroughly dried in an oven at 100 캜 for the filter paper.

(5) After the drying, the mass of the filter paper and the sample is measured, and the mass of the filter paper measured beforehand is subtracted from the value of the filter paper to calculate the mass of the dried sample: SM ₁ (g).

(6) The content G _BS (g / m 2) of the gel-like composition is calculated by the following equation (1).

G _BS (g / m 2) = [SM ₀ (g) -SM ₁ (g)] / SA (m 2)

On the other hand, the content of the gel-like composition was measured by cutting out a plurality of samples from a plurality of absorbent articles so that the total area of the sample exceeded 100 cm < 2 > ), And the average value of the content G _BS obtained from each measurement operation is adopted.

In the present invention, the coating method of the gel composition is not particularly limited, and any known coating method may be employed. For example, the gel-type composition may include an extrusion device having an ejection nozzle; Non-contact type coaters such as spiral coater, curtain coater, spray coater and dip coater; It can be coated on the top sheet by using a coating apparatus such as a contact type coater or the like.

The gel composition may be applied to the topsheet such as a nonwoven fabric, or may be coated on the topsheet in a production line of the absorbent article. The gel composition is preferably coated on the topsheet in the production line of the absorbent article from the viewpoint of restraining facility investment. In particular, from the viewpoint of suppressing contamination due to dropout of an emulsion or the like, It is preferable to coat the topsheet in a downstream process (for example, immediately before the process of individually wrapping the products).

In the absorbent article of the present invention, as the liquid permeable top sheet, for example, a sheet-like fibrous structure such as a nonwoven fabric or a woven fabric can be used. When a nonwoven fabric or a woven fabric is used as the topsheet, the fibers constituting the nonwoven fabric or the woven fabric include natural fibers and chemical fibers, and more specifically, cellulose fibers such as pulverized pulp and cotton; Regenerated cellulose such as rayon, fibril Rayon and the like; Semi-synthetic cellulose such as acetate and triacetate; Thermoplastic hydrophobic chemical fibers; And thermoplastic hydrophobic chemical fibers subjected to hydrophilization treatment. Examples of the thermoplastic hydrophobic chemical fiber include short fibers made of polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), etc., and fibers made of PE and PP graft polymers.

Examples of the nonwoven fabric include air-through nonwoven fabric, spunbond nonwoven fabric, point bond nonwoven fabric, spun lace nonwoven fabric, needle punch nonwoven fabric, meltblown nonwoven fabric, and combinations thereof (for example, SMS).

The nonwoven fabric or woven fabric is preferably subjected to hydrophilization treatment. The method of hydrophilizing treatment is not particularly limited, but a method of coating a surface of a nonwoven fabric or a woven fabric with a hydrophilic agent, a method of coating a surface of a nonwoven fabric or a fiber constituting the woven fabric with a hydrophilic agent, And a method of adding a hydrophilic agent to the synthetic resin, which is a raw material of the resin.

On the other hand, as the liquid impermeable backsheet, a laminate obtained by bonding a film including PE, PP or the like, a breathable resin film, a nonwoven fabric such as a spun bond or a spun lace to a resin film having permeability, And the like. Considering the flexibility of the absorbent article, for example, a low density polyethylene (LDPE) film having a basis weight of about 15 to about 30 g / m 2 is preferable.

In an embodiment of the present invention, the absorbent article may include a secondary sheet between the liquid permeable top sheet and the absorbent body. As the secondary sheet, the same liquid-permeable top sheet can be used.

In the absorbent article of the present invention, the absorbent body is not particularly limited, and any absorbent known in the art can be used. An example of the absorbent body is one in which the absorbent core is covered with a core wrap. Examples of the constituent elements of the absorbent core include hydrophilic fibers, and more specifically cellulose such as pulverized pulp and cotton; Regenerated cellulose such as rayon, fibril Rayon and the like; Semi-synthetic cellulose such as acetate and triacetate; Particle type polymers; Fiber type polymers; Thermoplastic hydrophobic chemical fibers; Hydrophilized thermoplastic hydrophobic chemical fibers; And any combination thereof. As a constituent element of the absorbent core, for example, a particle form comprising a superabsorbent polymer such as a sodium acrylate copolymer may be used.

The core wraps are not particularly limited as long as they have liquid permeability to the extent that liquid such as body fluids discharged from the human body can permeate and barrier properties to such an extent that the constituent elements of the absorbent core are not permeable. For example, a sheet-like fibrous structure such as a woven fabric or a nonwoven fabric may be mentioned. Examples of the woven fabric and the nonwoven fabric include natural fibers, chemical fibers, and tissues.

Another example of the absorber is a substantially sheet-like structure formed of an absorbent sheet or a polymer sheet. The thickness of the absorber is preferably in the range of 0.3 to 5.0 mm. The absorbent sheet or the polymer sheet is not particularly limited as long as it is used for general absorbent articles such as sanitary napkins.

A preferred embodiment of the absorbent article of the present invention is not particularly limited as long as it is an article for absorbing excretion discharged from a human body. Examples thereof include sanitary napkins, panty liners, diapers, and urine absorbent pads.

The present invention also relates to a nonwoven fabric. The nonwoven fabric of the present invention has the above-described gel-like composition in at least a part of a region of the wearer's skin in contact with the skin. The composition and the like of the gel composition used in the nonwoven fabric of the present invention are as described above.

Since the nonwoven fabric of the present invention has a gel composition having a suitable hardness, elongation and sustained release of an effective ingredient at least in a region in contact with the skin of the user and having a small tackiness, The ingredient can be continuously released to the skin of the wearer.

Also in the nonwoven fabric of the present invention, the gel-like composition is arranged in at least a part of the area in contact with the user's skin, for example, in the form of a ridge or a dot. Examples of the product including the nonwoven fabric include a mask and a wet tissue.

Example

Hereinafter, the present invention will be described in more detail by way of examples and comparative examples, but the present invention is not limited to the examples.

In preparing the gel-like compositions of the absorbent articles of the Examples and Comparative Examples of the present invention, the following commercially available products were used as various blending components.

1) The styrene-based thermoplastic elastomer (A1, A2)

a) a low molecular weight styrenic thermoplastic elastomer (A1)

Kraton G1652 (styrene-ethylene-butylene-styrene block copolymer (SEBS) having an Mw of 80,000, manufactured by Clayton Polymer Co., Ltd.)

SEPTON 4033 (styrene-ethylene / ethylene-propylene-styrene block copolymer (SEEPS) having an Mw of 100,000, manufactured by Kuraray Co., Ltd.)

SEPTON 8004 (styrene-ethylene-butylene-styrene block copolymer (SEBS) having Mw of 110,000, manufactured by Kuraray Co., Ltd.)

b) a high molecular weight styrenic thermoplastic elastomer (A2)

- Kleitone G1654 (styrene-ethylene-butylene-styrene block copolymer (SEBS) having an Mw of 200,000, manufactured by Clayton Polymer Co.)

SEPTON 4055 (styrene-ethylene / ethylene-propylene-styrene block copolymer (SEEPS) having an Mw of 250,000, manufactured by Kuraray Co., Ltd.)

SEPTON 2005 (styrene-ethylene-propylene-styrene block copolymer (SEPS) having an Mw of 260,000, manufactured by Kuraray Co., Ltd.)

SEPTON 2006 (styrene-ethylene-propylene-styrene block copolymer (SEPS) having an Mw of 280,000, manufactured by Kuraray Co., Ltd.)

2) Emulsion

a) a hydrocarbon oil (B)

PARLEAM EX (hydrogenated polyisobutene having kinematic viscosity of 10 mm < 2 > / s at 37.8 DEG C, manufactured by Nichiyu Corporation)

· Merch 6 (hydrogenated polyisobutene having kinematic viscosity of 20 mm 2 / s at 37.8 ° C, manufactured by Nichiyu Co., Ltd.)

Super Squalane (Squalane having kinematic viscosity of 18 mm < 2 > / s at 37.8 [deg.] C, manufactured by SCUATEC Corp.)

Moresco White P-200 (liquid paraffin having kinetic viscosity of 44 mm < 2 > / s at 37.8 DEG C, manufactured by MORESCO)

· Liquid paraffin (liquid paraffin having kinematic viscosity at 37.8 ° C of 75 mm 2 / s, manufactured by Kishida Kagaku Co., Ltd.)

b) Silicone oil (C)

· SH200-100cs (dimethylpolysiloxane having a kinematic viscosity at 25 ° C of 100 mm 2 / s, manufactured by Toray Dow Corning Co., Ltd.)

SH200-500cs (dimethylpolysiloxane having a kinematic viscosity at 25 캜 of 500 mm 2 / s, manufactured by Toray Dow Corning Co., Ltd.)

1. Preparation of gel composition

The above-mentioned various ingredients were put into a separable flask having the respective compositions shown in the following Table 1, and the contents were melted and mixed at 140 DEG C for 5 hours while stirring and then cooled to obtain gel compositions No. 1-1 to 1- 1-6 and 2-1 to 2-8 were obtained. The properties of each gel-like composition thus obtained were evaluated by the following various test methods (1) to (4). The results of various tests and evaluations are shown in Table 1.

2. Evaluation of gel composition

(1) Hardness

Using the gel composition obtained as described above, a test piece made of a cylindrical gel having a diameter of 40 mm and a thickness of 8 mm was produced. This test piece was set on a compact tablet tester EzTest (manufactured by Shimadzu Seisakusho) equipped with a stainless steel compression jig having a diameter of 120 mm and the test force (N) when the test piece was compressed by 4 mm at a speed of 5 mm / Were measured. The measured values were evaluated according to the following criteria.

2 points: more than 6 N, less than 41 N

1 point: more than 41 N, less than 101 N

0 point: less than 6 N or 101 N or more

(2) embrittlement

The test piece after the above hardness evaluation was visually observed, and the state of the test piece was evaluated according to the following criteria.

2 points: Not broken

1 point: slightly broken

0 point: is broken

(3) kidney

The gel composition thus obtained was hot-pressed under the conditions of 120 占 폚 and a pressure of 10 kg / cm2 to prepare a gel sheet having a thickness of 60 mm 占 60 mm 占 1 mm, A test piece of rectangular shape of mm x 60 mm was prepared. Both ends of the test piece in the longitudinal direction are held with thumb and forefinger using both hands, and the both ends are pulled in opposite directions (i.e., directions in which both ends are separated from each other), and the original The presence or absence of fracture at the time of stretching 5 cm, 7 cm and 10 cm from the length was observed. On the other hand, when the test piece was broken at the side, the test piece was re-performed again. The results thus obtained were evaluated according to the following criteria.

2 points: +10 cm was cut off when stretched

1 point: +7 cm It was broken when it was stretched

0 point: + 5 cm When I stretched out I was cut off

(4) The castle

Using the gel composition obtained as described above, a test piece made of a cylindrical gel having a diameter of 40 mm and a thickness of 8 mm was produced. On the top surface of this test piece, a commercially available tissue paper (one set of two sheets) having previously measured the mass was placed. After a load of 100 g was applied from above the tissue paper, the sample was allowed to stand at room temperature (23 ° C) for 24 hours, The paper was removed and its mass was measured. Then, the mass increase rate of the tissue paper is calculated from the mass (W ₁ ) measured in advance and the mass (W ₂ ) measured after being left for 24 hours on the basis of the following equation (2) , And evaluated according to the following criteria.

Mass increase rate (%) = (W ₂ -W ₁ ) / W ₁ × 100 (2)

2 points: mass increase rate (surplus) of 1.5% or more, less than 9.1%

1 point: the mass increase rate (sustained release) is 9.1% or more

0 point: mass increase rate (surplus amount) less than 1.5%

3. Manufacture of absorbent articles

Gel compositions No.1-1 to 1-6 and 2-1 to 2-8 obtained as described above were coated on a top sheet of a commercially available sanitary napkin in a liner shape to obtain a gel composition of Examples 1 to 6 and Comparative Example 1 Absorbent article (sanitary napkin) of ~ 8 was obtained.

4. Evaluation of absorbent articles

Using the absorbent articles of Examples 1 to 6 and Comparative Examples 1 to 8 obtained as described above, the feel when the surface of the gel composition coated on each top sheet was reciprocated 10 times from left to right with a finger was defined as " And "wettability and tackiness". In this sensory evaluation, 10 subjects were coated on the topsheet and allowed to stand at 23 캜 for one night, and the gel composition was touched, and a questionnaire was conducted according to the following evaluation criteria. On the other hand, the result of the questionnaire was the average of 10 persons.

[Softness]

2 points: elastic and also soft

1 point: There is no elasticity, but it is soft, or elastic, but hard

0 point: no elasticity and hardness

[Wettability and tackiness]

3 points: Finger is wet, not tacky

2 points: Finger is wet, has a little tackiness

1 point: Finger is wet and tender

0 point: Finger does not get wet, with or without preference

<Overall evaluation>

The absorbent article of each of Examples 1 to 6 and Comparative Examples 1 to 8 was evaluated on the basis of the following criteria based on the evaluation of the physical properties (1) to (4) of the gel composition and the sensory evaluation of the absorbent article . The results of sensory evaluation and comprehensive evaluation of the absorbent article are shown in Table 2 below.

○: The total score was 11.0 points or more, and no one gave 0 points in sensory evaluation

△: The total score was 11.0 or more, and the person who gave 0 points in the sensory evaluation

X: The total point is less than 11.0 points

As shown in Table 2, the absorbent articles of Examples 1 to 6 showed satisfactory results in the comprehensive evaluation. Particularly, in the absorbent articles of Examples 1 to 4, the gel compositions No. 1-1 to 1-4, which were used, were excellent in both hardness, elongation and sustained release, and a high evaluation result was obtained in the sensory evaluation of the absorbent article .

On the other hand, in the absorbent article of Comparative Example 1, since the gel composition No. 2-1 used contained only the low molecular weight styrenic thermoplastic elastomer (A1) as the styrenic thermoplastic elastomer, the gel became hard and brittleness was also observed.

In the absorbent article of Comparative Example 2, since the gel composition No. 2-2 used contained only the styrene thermoplastic elastomer (A2) having a high molecular weight as the styrene thermoplastic elastomer, the elongation of the gel was excellent, In the sensory evaluation of the absorbent article, tackiness was confirmed.

In the absorbent article of Comparative Example 3, since the blending amount of the hydrocarbon oil (B) in the gel-like composition No. 2-3 used was less than 500 parts by mass, the gel hardened, the amount of the gel was small, The wettability was poor.

In the absorbent article of Comparative Example 4, since the kinetic viscosity of the hydrocarbon oil (B) of the gel composition No. 2-4 used was higher than 50 mm &lt; 2 &gt; / s at 37.8 DEG C, .

The absorbent article of Comparative Example 5 had a weight ratio of (A1) / (A2) of the low molecular weight styrene thermoplastic elastomer (A1) and the high molecular weight styrene thermoplastic elastomer (A2) in the gel composition No. 2-5 used, = 95/5 to 50/50, the amount of the sustained release increased, and tackiness was confirmed in the sensory evaluation of the absorbent article.

In the absorbent article of Comparative Example 6, the dispersion degree of the styrene-based thermoplastic elastomer mixture (A) in the gel-like composition No. 2-6 used was larger than 1.60, so that elongation of the gel was poor and brittleness was also observed.

In the absorbent article of Comparative Example 7, since the kinematic viscosity at 25 캜 of the silicone oil (C) of the gel composition No. 2-7 used was larger than 200 mm &lt; 2 &gt; / s, .

In the absorbent article of Comparative Example 8, since the gel composition No. 2-8 used did not contain the silicone oil (C), the amount of surfactant was very small and the wettability was poor in sensory evaluation of the absorbent article.

Hereinafter, an aspect of the present invention will be exemplified.

One aspect (mode 1) of the present invention is an absorbent article having a liquid permeable top sheet, a liquid impermeable back sheet, and an absorbent body positioned between the top sheet and the back sheet, Wherein the gel composition comprises a styrenic thermoplastic elastomer (A1) having a weight average molecular weight of 100,000 or more and less than 180,000, and a block copolymer having a triblock or more block copolymer and a styrene-based thermoplastic elastomer (A1) / (A2) = 95/5 to 50/50 and having a molecular weight of not less than 180,000 and not more than 300,000, and a styrene-based thermoplastic elastomer (A2) 500 to 4800 parts by mass of a hydrocarbon oil (B) having a kinematic viscosity of 5 to 50 mm &lt; 2 &gt; / s at 37.8 DEG C per 100 parts by mass of the styrene thermoplastic elastomer mixture (A) having a dispersion degree (Mw / Mn) of 1.25 to 1.60 And a kinematic viscosity at 25 DEG C of 50 to 200 mm &lt; 2 &gt; / s Silicone oil (C) is an absorbent article containing 20 to 60 parts by weight.

In another aspect (mode 2) of the present invention, in the absorbent article of embodiment 1, the block copolymer has two or more block components comprising a styrene hard segment in the molecular chain.

In still another aspect (mode 3) of the present invention, in the absorbent article of embodiment 2, the block component of at least both ends in the molecular chain of the block copolymer is a block component composed of the styrene hard segment.

In another aspect (mode 4) of the present invention, in the absorbent article of any one of the above-mentioned aspects 1 to 3, the block copolymer is a styrene-butadiene-styrene block copolymer, a styrene- Ethylene-propylene-styrene block copolymer, styrene-isoprene-butylene-styrene block copolymer, styrene-isoprene-styrene block copolymer, styrene-ethylene-propylene-styrene block copolymer and styrene- . &Lt; / RTI &gt;

In another aspect (mode 5) of the present invention, in the absorbent article of any one of the above-mentioned aspects 1 to 4, the hydrocarbon oil (B) is at least one selected from the group consisting of hydrogenated polyisobutene, liquid paraffin, squalane and squalene At least one selected.

In still another embodiment (mode 6) of the present invention, in the absorbent article of any one of the above-mentioned aspects 1 to 5, the silicone oil (C) is a diorganopolysiloxane or a cyclic siloxane.

In another aspect (aspect 7) of the present invention, in the absorbent article of any one of the above-mentioned aspects 1 to 6, the silicone oil (C) is at least one selected from the group consisting of dimethylpolysiloxane, methylphenylpolysiloxane and cyclopentasiloxane One species.

In another aspect (aspect 8) of the present invention, in the absorbent article of any one of the above-mentioned aspects 1 to 7, the gel composition is formed on the skin surface side of the topsheet in a shape of a ridge or a dot It is painted.

In still another aspect (mode 9) of the present invention, in the absorbent article according to any one of the aspects 1 to 8, the absorbent article is a sanitary napkin, a panty liner, a diaper, or a urine absorbent pad.

Another aspect (aspect 10) of the present invention is a nonwoven fabric having a gel-like composition on its surface, wherein the gel-like composition is a styrene-based thermoplastic resin having a weight average molecular weight of 100,000 or more and less than 180,000, And a styrene thermoplastic elastomer (A2) having a weight average molecular weight of 180,000 or more and 300,000 or less and having a triblock or more block copolymer in an amount of (A1) / (A2) = 95 / 5-50 / 50 parts by mass of the styrene thermoplastic elastomer mixture (A) having a kinematic viscosity at 37.8 DEG C of from 5 to 50 mm &lt; 2 &gt; / s and a molecular weight distribution (Mw / Mn) of from 1.25 to 1.60. 500 to 4800 parts by mass of a hydrocarbon oil (B) and 20 to 60 parts by mass of a silicone oil (C) having a kinematic viscosity at 25 DEG C of 50 to 200 mm &lt; 2 &gt; / s.

1: absorbent article 2: top sheet
3: absorber 4: side sheet
5: embossed part 6: gel-like composition

Claims (10)

1. An absorbent article having a liquid permeable top sheet, a liquid impermeable back sheet, and an absorbent body positioned between the top sheet and the back sheet,
Wherein the topsheet comprises a gel composition on the skin surface side,
Wherein the gel composition comprises a styrenic thermoplastic elastomer (A1) having a weight average molecular weight of 100,000 or more and less than 180,000, and further comprising a block copolymer having a triblock or more block copolymer, and a styrene block copolymer having a weight average molecular weight of 180,000 or more and 300,000 or less, (A1) / (A2) = 95/5 to 50/50 and a molecular weight dispersion degree (Mw / Mn) of 1.25 to 1.60 Based on 100 parts by mass of the styrene-based thermoplastic elastomer mixture (A)
500 to 4800 parts by mass of a hydrocarbon oil (B) having a kinematic viscosity (kinematic viscosity) of 5 to 50 mm 2 / s at 37.8 ° C and 20 to 60 parts by mass of a silicone oil (C) having a kinematic viscosity at 50 ° C to 200 mm 2 / Mass part of the absorbent article. The absorbent article according to claim 1, wherein the block copolymer has two or more block components composed of a styrene hard segment in the molecular chain. The absorbent article as set forth in claim 2, wherein at least the block components at both ends of the molecular chain of the block copolymer are block components comprising the styrene hard segment. The block copolymer according to any one of claims 1 to 3, wherein the block copolymer is selected from the group consisting of a styrene-butadiene-styrene block copolymer, a styrene-ethylene-butylene-styrene block copolymer, a styrene-isoprene- Wherein at least one selected from the group consisting of styrene-ethylene-propylene-styrene block copolymer, styrene-isoprene-styrene block copolymer, styrene-ethylene-propylene-styrene block copolymer and styrene-ethylene-ethylene-propylene-styrene block copolymer. The absorbent article according to any one of claims 1 to 3, wherein the hydrocarbon oil (B) is at least one selected from the group consisting of hydrogenated polyisobutene, liquid paraffin, squalane and squalene. The absorbent article according to any one of claims 1 to 3, wherein the silicone oil (C) is a diorganopolysiloxane or a cyclic siloxane. The absorbent article according to any one of claims 1 to 3, wherein the silicone oil (C) is at least one selected from the group consisting of dimethylpolysiloxane, methylphenylpolysiloxane and cyclopentasiloxane. The absorbent article as set forth in any one of claims 1 to 3, wherein the gel composition is coated on the skin surface side of the topsheet in a shape of a ridge or a dot in plan view. The absorbent article according to any one of claims 1 to 3, wherein the absorbent article is a sanitary napkin, a panty liner, a diaper, or a urine absorbent pad. As a nonwoven fabric having a gel-like composition on its surface,
Wherein the gel composition comprises a styrenic thermoplastic elastomer (A1) having a weight average molecular weight of 100,000 or more and less than 180,000, and further comprising a block copolymer having a triblock or more block copolymer, and a styrene block copolymer having a weight average molecular weight of 180,000 or more and 300,000 or less, (A1) / (A2) = 95/5 to 50/50 and a molecular weight dispersion degree (Mw / Mn) of 1.25 to 1.60 Based on 100 parts by mass of the styrene-based thermoplastic elastomer mixture (A)
500 to 4800 parts by mass of a hydrocarbon oil (B) having a kinematic viscosity at 5 to 50 mm 2 / s at 37.8 ° C and 20 to 60 parts by mass of a silicone oil (C) having a kinematic viscosity at 25 ° C of 50 to 200 mm 2 / Nonwovens to be one.

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