TWI648036B - Absorbent article - Google Patents

Abstract

An object of the present invention is to provide an absorbent article which is capable of continuously releasing an emulsion which protects a user's skin and which is excellent in rewet property. The absorbent article of the present invention is as follows.

The present invention is an absorbent article (1) characterized by comprising a liquid permeable layer (2), a liquid impermeable layer, an absorbent layer (3), and a colloidal emulsion (6) absorbent article (1) Wherein the colloidal emulsion (6) comprises, as a colloidalizing agent, a styrene-based elastomer, and at least a part of two colloidal regions (8) adjacent to each other in a plurality of colloidal regions (8) as a hydrocarbon of the emulsion, Two adjacent points (13) of two colloidal regions (8) adjacent to each other, an intermediate point (14) in the middle thereof, a point (15) corresponding to two adjacent points, and a point corresponding to the intermediate point (16) ) satisfying the relationship of the following i) to iii), i) both water contact angles of the two adjacent points (13) are above 85°, and ii) the water contact angle in the intermediate point (14) is equivalent to the above two adjacent points The water contact angle in point (15) is large, and iii) the difference between the water contact angle of the intermediate point (14) and the water contact angle in the intermediate point (16) is larger than -3 (°).

Description

Absorbent article

The present invention relates to an absorbent article.

Absorbent articles, such as sanitary napkins and pads, have been gradually developed to improve basic performance through years of accumulated technology. Compared with the past, absorption of excretions such as menstrual blood, leakage, etc. occur less frequently. The pursuit of high performance, for example, has a sense of closeness to the skin.

And, for example, the absorbent article of claim 1 is characterized in that at least a portion of the outer surface of the top sheet comprises an effective amount of an emulsion coating which is semi-solid or solid at 20 ° C and capable of Partially moved to the user's skin. Moreover, the above emulsion coating comprises: 10 to 95% (i) having plasticity or flow consistency at 20 ° C, and comprising a softener selected from a petroleum base, a fatty acid ester softener, an alkyl ethoxylation a softening agent, and one of such a mixture, and a softening agent that does not substantially contain moisture, and 5 to 90% of (ii) an immobilizing substance capable of fixing the softening agent to the outer surface of the top sheet, and The immobilized substance has a melting point of at least 35 ° C, preferably at least 40 ° C, and is selected from the group consisting of polyhydroxyalkanoates, polyhydroxy fatty acid decylamines, C _14- C ₂₂ fatty alcohols, C _12- C ₂₂ fatty acids, C _12- C ₂₂ fatty alcohol ethoxylate, and mixtures of these.

[Previous Technical Literature] [Citation]

[Citation 1] Japanese Special Report No. 10-509896

In Citation 1, an immobilized material having a melting point of 35 ° C or higher is crystallized at room temperature (25 ° C) in emulsion coating, and the viscosity of the emulsion coating is increased, and the emulsion coating is immobilized. effect.

However, when the immobilized material is used to imprint the emulsion (high viscosity), there is a problem that the "softener" of the active ingredient is difficult to release from the emulsion coating. Moreover, even if the emulsion is coated immovable (high viscosity), under the high pressure such as body pressure, the emulsion coating moves to the inside of the absorbent article (the void of the fibers of the top sheet, etc.), and there is a "softener". It is difficult to continue to have problems with the user's skin.

Therefore, an object of the present invention is to provide an absorbent article which can continuously release an emulsion which protects the skin of a user and which is excellent in rewet property.

The present inventors have found an absorbent article comprising: a liquid permeable layer having a skin contact region and a skin non-contact region, and a liquid impermeable layer, and the liquid permeable layer and the liquid impermeable layer; The absorbent layer, the colloidal emulsion, and the absorbent article having a thickness direction, wherein the colloidal emulsion comprises a polystyrene block as a colloidalizing agent and a hydrocarbon as an emulsion, and the liquid permeable layer is The skin contact area has a plurality of colloidal regions having the colloidal emulsion and a non-colloidal region having no colloidal emulsion, and the skin non-contacting region has a plurality of colloidal regions and the non-colloidal region respectively at the thickness a plurality of colloidal region repeating domains and a non-colloidal region repeating region in which the direction is repeated, wherein at least one of the two colloidal regions adjacent to each other among the plurality of colloidal regions and the two colloidal regions adjacent to each other are closest to each other Two adjacent points, in the middle of the two adjacent points, and exist in the middle of the non-colloidal area And the two adjacent points are overlapped in the thickness direction, and are present at two adjacent points of the colloidal region repeating region, overlap with the intermediate point in the thickness direction, and exist in the non-colloidal region repeating domain The intermediate point has the following relationship i) to iii), i) the water contact angle of two adjacent points, both of which are above 85°, ii) the water contact angle in the intermediate point is higher than the above two adjacent points The water contact angle in the point is large, and iii) the water contact angle of the intermediate point is larger than the water contact angle of the intermediate point by -3 (°).

The absorbent article of the present invention can continuously release an emulsion that protects the skin of the user, and is excellent in rewet property.

1‧‧‧Absorbables

2‧‧‧Top sheet

3‧‧‧ absorber

4‧‧‧Side sheet

5‧‧‧ Imprinting Department

6‧‧‧colloidal emulsion

7‧‧‧ Skin contact area

8‧‧‧colloidal area

9‧‧‧ Non-colloidal area

10‧‧‧ Skin contact area

11‧‧‧colloidal region repeat domain

12‧‧‧ Non-colloidal region repeat domain

13‧‧‧ Adjacent points

14‧‧‧ intermediate point

15‧‧‧The neighboring point is quite a bit

16‧‧‧The middle point is quite a bit

17‧‧‧ Emulsion

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

Fig. 2 is a cross-sectional view showing a section II-II of the area A of Fig. 1.

Fig. 3 is a schematic view for explaining the effects of the present invention.

Fig. 4 is a plan view showing an absorbent article 1 according to an embodiment of the present invention.

FIG. 5 is an enlarged view of a region A of FIG. 4. FIG.

Fig. 6 is a partial plan view for explaining an absorbent article 1 different from the embodiment of the present invention.

[Formation of the Invention]

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

The absorbent article of the present invention comprises: a liquid permeable layer having a skin contact region and a skin non-contact region; an absorbing layer between the liquid permeable layer and the liquid permeable layer and the liquid opaque layer; Body lotion with a thickness direction.

[colloidal emulsion]

The above colloidal emulsion contains a polystyrene block as a colloidalizing agent and a hydrocarbon as an emulsion.

The colloidalizing agent contains a styrene-based elastomer in order to retain the components of the above emulsion.

The styrene-based elastomer preferably has a hard segment and a soft segment, and is preferably a polystyrene block as the hard segment, and a polyolefin block as the soft segment.

The above polystyrene block includes not only a block of a homopolymer of styrene (that is, a polystyrene block) but also a block of a homopolymer of α-methylstyrene ( That is, a block of a poly-α-methylstyrene block and a copolymer of styrene and α-methylstyrene.

As the above polyolefin block, there may be mentioned, for example, a block of a homopolymer of polyolefin, such as a polyethylene block, a polypropylene block, a polybutene block, and a polybutadiene block, and a poly A block formed of a copolymer of an olefin, for example, a copolymer of ethylene, propylene, butylene, and butadiene.

Further, in the present specification, butadiene is also used as a normal olefin monomer.

Further, the soft segment further comprises a hydrogen adduct of a polybutadiene block and a hydrogen adduct of a block of butadiene and a copolymer of ethylene, propylene, butylene and butadiene. .

The styrene-based elastomer preferably has a hard segment at both ends, and one or a plurality of soft segments are preferably provided between the two.

Specific examples of the styrene-based elastomer are as follows.

(i) polystyrene-block-poly(ethylene-co-propylene)

(The following may be omitted as "SEP")

(ii) polystyrene-block-poly(ethylene-co-propylene)-block-polystyrene

(The following may be omitted as "SEPS")

(iii) polystyrene-block-poly(ethylene-co-butylene)-block-polystyrene

(The following may be omitted as "SEBS")

(iv) polystyrene-block-polyethylene-block-poly(ethylene-co-propylene)-block-polystyrene

(The following may be omitted as "SEEPS")

The styrene-based elastomer preferably has a weight average molecular weight of 5,000 to 500,000, more preferably 10,000 to 400,000, and still more preferably 50,000 to 300,000. When the weight average molecular weight is less than 5,000, the styrene-based elastomer tends to be difficult to maintain in the colloidal structure, and if the weight average molecular weight exceeds 500,000, the feeling of use tends to decrease.

Further, the method for measuring the weight average molecular weight will be described later.

The styrene-based elastomer preferably contains 10 to 50% by mass of a polystyrene block and 50 to 90% by mass of a polyolefin block, and more preferably 15 to 40% by mass of a polystyrene block. 60 to 85% by mass of polyolefin The hydrocarbon block, and more preferably contains 18 to 35% by mass of a polystyrene block and 65 to 82% by mass of a polyolefin block.

When the amount of the polystyrene block is less than 10% by mass, the polystyrene block tends to be difficult to form a micron-separated structure described later. When the amount of the polystyrene block exceeds 50% by mass, the amount of the polyolefin block capable of holding the emulsion is reduced, so that the amount of the emulsion that can be held tends to be small. Further, the amount of the micron layer separation structure of the polystyrene block is increased, and the formed colloidal emulsion is solidified, which tends to deteriorate the feeling of use.

The reason why the above styrene-based elastomer forms a colloidal emulsion is as follows. The hard segments of the styrene elastomer will agglomerate to each other to form a range and function as a crosslinking point. On the other hand, the soft segment will play the role of the mesh connecting these cross-linking points. As a result, the styrene-based elastomer has a function as an elastomer.

When the styrene-based elastomer is mixed with the above emulsion, particularly with a hydrocarbon, the soft segment of the styrene-based elastomer retains the emulsion, and on the other hand, the hard segment is maintained in a state of being formed. As a result, the mixture of the styrene-based elastomer and the above emulsion (colloidal emulsion) has the function of an elastomer having a lower compressive stress than the styrene-based elastomer monomer.

Moreover, the above emulsion is only retained in the looser mesh in the soft section of the styrenic elastomer and can be moved to the surface of the colloidal emulsion.

The above emulsion contains a hydrocarbon. In the present specification, "hydrocarbon" means a compound in which carbon and hydrogen are formed. Examples of the hydrocarbon include a chain hydrocarbon such as a paraffinic hydrocarbon (excluding a double bond and a triple bond, also referred to as an alkane), and a normal olefinic hydrocarbon. (containing one double bond, also referred to as an alkene), an acetylene hydrocarbon (containing one triple bond, also referred to as an alkyne), and a hydrocarbon containing two or more bonds selected from the group consisting of a double bond and a triple bond And cyclic hydrocarbons such as aromatic hydrocarbons and alicyclic hydrocarbons.

The hydrocarbon is preferably a chain hydrocarbon or an alicyclic hydrocarbon, and more preferably a chain hydrocarbon, and is a paraffinic hydrocarbon, a normal olefinic hydrocarbon, and a hydrocarbon containing two or more double bonds (excluding a triple bond) More preferably, it is more preferred as a paraffinic hydrocarbon.

The chain hydrocarbons include linear hydrocarbons and branched hydrocarbons.

The above hydrocarbon has a dynamic viscosity of preferably 0.01 to 80 mm ² /s at 40 ° C, a water absorbing ratio of 0.01 to 4.0% by mass, and a weight average molecular weight of less than 1,000. This is because the hydrocarbon acts as a body fluid slip imparting agent to be described later.

In the colloidal emulsion of the present invention, an emulsion (e.g., a hydrocarbon) will have a certain amount of oozing out of the surface of the colloidal emulsion. The emulsion that oozes the surface will move to the user's skin, or it will slide down with the body fluids such as menstrual blood and urine until the inside of the absorber disappears, and then the new emulsion will ooze out from the colloidal emulsion. Therefore, the colloidal emulsion is capable of continuously releasing the emulsion.

The above emulsion preferably contains 50 to 100% by mass, more preferably 60 to 100% by mass, and still more preferably 70 to 100% by mass of the above hydrocarbon. This is because from the viewpoint of formation of colloids.

In the above colloidal emulsion, as the above-mentioned emulsion, in addition to the above hydrocarbons, it is possible to further comprise a component which is well known as an emulsion in the technical field of the invention.

In the above-mentioned colloidal emulsion, it is preferable to further include a body fluid slip imparting agent as the above-mentioned emulsion, and the body fluid slip imparting agent has an IOB of more than 0.00 and 0.60 or less, and 0.01 to 80 mm ² /s at 40 ° C. The dynamic viscosity, the water holding ratio of 0.01 to 4.0% by mass, and the weight average molecular weight of less than 1,000.

The above-mentioned body fluid slip imparting agent is the same as the "blood modifier" described in the specification of International Publication No. 2012/133724, and is similarly described in the specification of International Publication No. 2013/129236. The "slipperiness imparting agent" is the same component.

When the body fluid slip imparting agent is contained in the colloidal emulsion, the body fluid slip imparting agent is continuously released from the colloidal emulsion, and the body fluid or the like reaching the liquid permeable layer can be quickly slipped to the inside of the absorbent body over a long period of time. .

IOB (Inorganic Organic Balance) is an index indicating the balance between hydrophilicity and lipophilicity, and the present specification means a value calculated according to the formula of Oda et al.: IOB=inorganic value/organicity value.

The above inorganic value and organic value mean an organic concept map described in Fujita Mu's "Organic Compound Prediction and Organic Concept Map" Chemical Region Vol. 11, No. 10 (1957) p. 719-725).

The organic and inorganic values of the main bases described by Fujita are summarized in Table 1 below.

The above dynamic viscosity is measured according to "5. Dynamic viscosity test method" of JIS K 2283:2000, and measured at a test temperature of 40 ° C using a Cannon-Fenske counter-flow viscosity meter.

In the present specification, the above-mentioned "water holding ratio" means the ratio of the water which retains the substance, and is measured by the following.

(1) The test tube, the rubber stopper, the substance to be measured, and deionized water were allowed to stand in a thermostatic chamber at 40 ° C for 24 hours.

(2) In the above-mentioned constant temperature chamber, 5.0 g of the substance to be measured and 5.0 g of deionized water were placed in a test tube of 20 mL.

(3) In the above-mentioned constant temperature chamber, the test tube was clamped with a rubber, rotated once, and allowed to stand for 5 minutes.

(4) In the above-mentioned constant temperature chamber, 3.0 g of the substance to be measured (usually the upper layer) was taken up to a glass vessel having a diameter of 90 mm and a mass of W ₀ (g).

(5) The above vessel was heated in an oven at 105 ° C for 3 hours to evaporate water, and the mass of each vessel was measured: W ₁ (g).

(6) The water holding ratio is calculated according to the following formula.

Water holding capacity (% by mass) = 100 × [W ₀ (g) - W ₁ (g)] / 3.0 (g)

Three measurements were performed and the average was used.

In the present specification, the above "weight average molecular weight" includes a polydisperse compound (for example, a compound produced by sequential polymerization, an ester of a plurality of fatty acids and a plurality of aliphatic monohydric alcohols), and a single compound (for example, one kind) the concept of generating a fatty acid with one of aliphatic monohydric alcohol esters), and N _i mean a molecule of molecular weight M _i (i = 1, or i = 1,2 ...) of the system formed by the following The formula: M _w = Σ N _i M _i ² / Σ N _i M _i is obtained by M _w .

In the present specification, the weight average molecular weight means a polystyrene-converted value obtained by gel permeation chromatography (GPC).

The measurement conditions of GPC are as follows, for example.

Model: (share) Hitachi High-Technologies system High performance liquid chromatography Lachrom Elite

Pipe column: SHODEX KF-801, KF-803 and KF-804 made by Showa Denko (share)

Lysate: THF

Flow rate: 1.0mL/min

Driving amount: 100μL

Detection: RI (differential refractometer)

The body fluid slip imparting agent is preferably a group of the following (i) and (ii), and any combination selected from the group consisting of (i) a compound having (i-1) and (i-2), (i-1) is a hydrocarbyl moiety, (i-2) is a group of CC single bonds inserted into the above hydrocarbyl moiety, and is selected from the group consisting of a carbonyl group (-CO-) and an oxy group (-O-). Or a plurality of identical or different groups, and (ii) a compound having (ii-1) and (ii-2) and (ii-3), (ii-1) being a hydrocarbon moiety, and (ii-2) being Inserted between the CC single bonds of the above hydrocarbyl moiety, and selected from one or a plurality of identical or dissimilar groups in the group of carbonyl (-CO-) and oxy (-O-), (ii-3) It is a hydrogen atom substituted for the above hydrocarbon moiety, and is selected from one or a plurality of identical or different groups in a group of a carboxyl group (-COOH) and a hydroxyl group (-OH).

Further, the above hydrocarbon group is synonymous with the above hydrocarbon group.

In the compounds of the above (i) and (ii), when two or more oxy groups (-O-) are inserted, each oxy group (-O-) is not adjacent. Therefore, the compound of the above (i) and (ii) does not contain a compound of a continuous oxy group (so-called peroxide).

The body fluid slip imparting agent is further preferably the following (i') and (ii'), and a group selected from any combination of these, (i') having (i'-1) and (i' a compound of -2), (i'-1) is a hydrocarbyl moiety, (i'-2) is a CC single bond inserted into the above hydrocarbyl moiety, and is selected from a carbonyl bond (-CO-), an ester bond (- One or a plurality of identical or different bonds in a group of COO-), carbonate bonds (-OCOO-), and ether bonds (-O-), and (ii') a compound having (ii'-1) and (ii'-2) and (ii'-3), (ii'-1) being a hydrocarbon moiety, and (ii'-2) being inserted into the above hydrocarbon moiety Between the CC single bonds, and one selected from the group consisting of a carbonyl bond (-CO-), an ester bond (-COO-), a carbonate bond (-OCOO-), and an ether bond (-O-) a plurality of identical or distinct bonds, (ii'-3) being a hydrogen atom replacing the above hydrocarbyl moiety, and one or a plurality of the same selected from the group consisting of a carboxyl group (-COOH) and a hydroxyl group (-OH) Or the basis of difference.

Further, the above hydrocarbon group is the same as the above hydrocarbon group.

In the above compounds (i') and (ii'), when two or more identical or different bonds are inserted, that is, a bond selected from a carbonyl bond (-CO-), an ester bond (-COO-), or a carbonate bond ( When -OCOO-) and two or more identical or different bonds in the ether bond (-O-), the respective bonds are not adjacent, and at least one carbon atom is interposed between the respective bonds.

Examples of the body fluid slip imparting agent include an ester of (a ₁ ) a chain hydrocarbon tetrahydric alcohol and at least one fatty acid, and an ester of (a ₂ ) a chain hydrocarbon triol and at least one fatty acid, (a _{3 )} An ester of a chain hydrocarbyl glycol with at least one fatty acid, (b ₁ ) a chain hydrocarbyl tetraol and at least one aliphatic monohydric alcohol, (b ₂ ) a chain hydrocarbyl triol and at least 1 An aliphatic monohydric alcohol ether, (b ₃ ) a chain hydrocarbyl diol and at least one aliphatic monohydric alcohol ether, (c ₁ ) a chain hydrocarbyl tetracarboxylic acid having four carboxyl groups, a hydroxy acid, An ester of an alkoxylic acid or oxyacid with at least one aliphatic monohydric alcohol, (c ₂ ) a chain hydrocarbyl tricarboxylic acid having three carboxyl groups, a hydroxy acid, an alkoxy acid or an oxyacid with at least one aliphatic mono An ester of an alcohol, (c ₃ ) a chain hydrocarbyl dicarboxylic acid having two carboxyl groups, an ester of a hydroxy acid, an alkoxy acid or an oxyacid with at least one aliphatic monohydric alcohol, (d ₁ ) an aliphatic monohydric alcohol Ethers of aliphatic and monohydric alcohols, (d ₂ )dialkyl ketones, esters of (d ₃ ) fatty acids and aliphatic monohydric alcohols, (d ₄ )dialkyl carbonates, (e ₁ )polyoxy C ₃ ~ C ₆ alkylene glycol, (e ₂₎ polyoxy C ₃ ~ C ₆ alkyl At least one fatty alcohol and the ester, and (e ₃₎ polyoxy C ₃ ~ C ₆ alkylene glycol and at least one of the aliphatic monohydric alcohol ethers, and any combination of these.

These compounds are described below.

[(a ₁ ) an ester of a chain hydrocarbon-based tetraol with at least one fatty acid]

The chain hydrocarbon-based tetraol means a compound in which a hydrogen atom of the above-mentioned chain hydrocarbon group (four in total) is substituted by a hydroxyl group (-OH) (total of four) as the above-mentioned chain hydrocarbon-based tetraol and at least one An ester of a fatty acid, for example, the following formula (1): a tetraester of pentaerythritol and a fatty acid, and the following formula (2): a pentaerythritol and a fatty acid triester, the following formula (3): Diester of pentaerythritol and fatty acid, formula (4): a monoester of pentaerythritol and a fatty acid. (wherein, R ¹ to R ⁴ are each a chain hydrocarbon group)

As the fatty acid (R ¹ COOH, R ² COOH, R ³ COOH, and R ⁴ COOH) constituting the above ester of pentaerythritol and a fatty acid, for example, a saturated fatty acid such as a C ₂ - C ₃₀ saturated fatty acid such as acetic acid (C ₂ ) may be mentioned. (C ₂ represents a carbon number, a carbon number corresponding to R ¹ C, R ² C, R ³ C or R ⁴ C, the same applies hereinafter), propionic acid (C ₃ ), butyric acid (C ₄ ), and isomers thereof For example, methyl 2-propionate (C ₄ ), valeric acid (C ₅ ) and isomers thereof, such as methyl 2-butyrate (C ₅ ), methyl 2,2-dipropionate (C ₅ ) , hexanoic acid (C ₆ ), heptanoic acid (C ₇ ), octanoic acid (C ₈ ) and isomers thereof, such as ethyl 2-hexanoate (C ₈ ), citric acid (C ₉ ), citric acid (C _{10 )} ), dodecanoic acid (C ₁₂ ), tetradecanoic acid (C ₁₄ ), hexadecanoic acid (C ₁₆ ), heptadecanoic acid (C ₁₇ ), octadecanoic acid (C ₁₈ ), eicosanoic acid (C ₂₀ ), Twenty-two acid (C ₂₂ ), tetracosic acid (C ₂₄ ), hexacylic acid (C ₂₆ ), octadecanoic acid (C ₂₈ ), tridecanoic acid (C ₃₀ ), etc., and not listed These isomers.

The above fatty acids can also be unsaturated fatty acids. Examples of the unsaturated fatty acid include C ₃ to C ₂₀ unsaturated fatty acids such as monounsaturated fatty acids such as crotonic acid (C ₄ ), myristate oleic acid (C ₁₄ ), palmitoleic acid (C ₁₆ ), Octadecenoic acid (C ₁₈ ), oleic acid (C ₁₈ ), trans 11-octadecenoic acid (C ₁₈ ), oleic acid (C ₂₀ ), eicosenoic acid (C ₂₀ ), etc., diunsaturated Fatty acids, such as linoleic acid (C ₁₈ ), eicosadienoic acid (C ₂₀ ), etc., triunsaturated fatty acids, such as linoleic acid, such as α -linolenic acid (C ₁₈ ) and γ-sub-Asia Sesic acid (C ₁₈ ), terpineic acid (C ₁₈ ), tung acid, such as α -tungstic acid (C ₁₈ ), β-tungstic acid (C ₁₈ ), metic acid (C ₂₀ ), di-γ-γ- Sublinoleic acid (C ₂₀ ), eicosatrienoic acid (C ₂₀ ), etc., tetraunsaturated fatty acids such as stearidonic acid (C ₂₀ ), arachidonic acid (C ₂₀ ), peanut oleic acid ( C ₂₀ ) Iso-penta-unsaturated fatty acids, such as bosseopentaenoic acid (C ₁₈ ), eicosapentaenoic acid (C ₂₀ ), and the like, and some of the hydrogen adducts thereof.

[(a ₂ ) an ester of a chain hydrocarbyl triol with at least one fatty acid]

The chain hydrocarbon-based triol means a compound in which a hydrogen atom (total of three) of the above-mentioned chain hydrocarbon group is substituted by a hydroxyl group (-OH) (total of three) as the above-mentioned chain hydrocarbon triol and at least one An ester of a fatty acid, for example, the following formula (5): The glycerol and fatty acid triester, the following formula (6): a diester of glycerol and a fatty acid, and the following formula (7): (wherein, R ⁵ to R ⁷ are each a chain hydrocarbon group) are monoesters of glycerin and a fatty acid.

Further, the fatty acid is as described above.

[(a ₃ ) ester of a chain hydrocarbon-based diol with at least one fatty acid]

The above-mentioned chain hydrocarbon-based glycol means a compound in which a hydrogen atom (two in total) of the above-mentioned chain hydrocarbon group is substituted by a hydroxyl group (-OH) (total of two) as the above-mentioned chain hydrocarbon-based glycol and at least 1 The ester of a fatty acid is, for example, the following formula (8): R ⁸ COOC _k H _2k OCOR ⁹ (8) (wherein k is an integer of 2 to 6, and R ⁸ and R ⁹ are each a chain hydrocarbon group) C ₂ ~ C ₆ diester of ethylene glycol and fatty acid, and the following formula (9): R ⁸ COOC _k H _2k OH (9) (wherein k is an integer of 2 to 6, and R ⁸ is a chain a monoester of a C ₂ -C ₆ ethylene glycol with a fatty acid.

Further, the fatty acid is as described above.

[(b ₁ ) an ether of a chain hydrocarbyl tetraol and at least one aliphatic monohydric alcohol]

Examples of the (b ₁ ) chain hydrocarbyl tetrahydric alcohol and at least one aliphatic monohydric alcohol ether include the following formulas (10) to (13): (wherein, R ¹⁰ to R ¹³ are each a chain hydrocarbon group), and a tetraether, a triether, a diether, and a monoether of the pentaerythritol and the aliphatic monohydric alcohol.

Further, the chain hydrocarbon-based tetrahydric alcohol is as described above.

Examples of the aliphatic monohydric alcohols include saturated aliphatic monohydric alcohols and unsaturated aliphatic monohydric alcohols.

Examples of the saturated aliphatic monohydric alcohols include, for example, C ₁ to C ₂₀ saturated aliphatic monohydric alcohols, for example, methanol (C ₁ ) (C ₁ represents a carbon number, the same applies hereinafter), ethanol (C ₂ ), and propanol. (C ₃ ) and its isomers, such as isopropanol (C ₃ ), butanol (C ₄ ), and isomers thereof, such as sec-butanol (C ₄ ) and tert-butanol (C ₄ ), Pentanol (C ₅ ), hexanol (C ₆ ), heptanol (C ₇ ), octanol (C ₈ ) and isomers thereof, such as 2-ethylhexanol (C ₈ ), decyl alcohol (C ₉ ), decyl alcohol (C ₁₀ ), dodecyl alcohol (C ₁₂ ), tetradecyl alcohol (C ₁₄ ), cetyl alcohol (C ₁₆ ), heptadecyl alcohol (C ₁₇ ), stearyl alcohol (C ₁₈ ), and Decanol (C ₂₀ ), and such isomers not listed.

The unsaturated aliphatic monohydric alcohol is one in which one C-C single bond of the above saturated aliphatic monohydric alcohol is substituted by a C=C double bond, and examples thereof include oleyl alcohol.

[(b ₂ ) an ether of a chain hydrocarbon monohydric alcohol and at least one aliphatic monohydric alcohol]

Examples of the (b ₂ ) chain hydrocarbon monohydric alcohol and at least one aliphatic monohydric alcohol ether include the following formulas (14) to (16): (wherein, R ¹⁴ to R ¹⁶ are each a chain hydrocarbon group, respectively), a triglyceride of an aliphatic monohydric alcohol, a diether, and a monoether.

Further, the chain hydrocarbon monohydric alcohol and the aliphatic monohydric alcohol are as described above.

[(b ₃ ) ether of a chain hydrocarbon-based diol and at least one aliphatic monohydric alcohol]

Examples of the (b ₃ ) chain hydrocarbyl diol and at least one aliphatic monohydric alcohol ether include the following formula (17): R ¹⁷ OC _n H _2n OR ¹⁸ (17) (wherein n is An integer of 2 to 6 and R ¹⁷ and R ¹⁸ are a chain hydrocarbon group, respectively, a diether of a C ₂ -C ₆ ethylene glycol and an aliphatic monohydric alcohol, and the following formula (18): R ¹⁷ OC _n H _2n OH (18) (wherein, n is an integer of 2 to 6, and R ¹⁷ is a chain hydrocarbon group) of a monoether of C ₂ -C ₆ ethylene glycol and an aliphatic monohydric alcohol.

Further, the chain hydrocarbon-based diol and the aliphatic monohydric alcohol are as described above.

[(c ₁ ) an ester of a chain hydrocarbon tetracarboxylic acid, a hydroxy acid, an alkoxy acid or an oxyacid having 4 carboxyl groups and at least one aliphatic monohydric alcohol]

(c ₁ ) an ester of a chain hydrocarbon tetracarboxylic acid, a hydroxy acid, an alkoxy acid or an oxyacid having four carboxyl groups and at least one aliphatic monohydric alcohol, for example, a monoester, a diester or a triester thereof Tetraester.

[(c ₂ ) an ester of a chain hydrocarbon group of a tricarboxylic acid having three carboxyl groups, a hydroxy acid, an alkoxy acid or an oxyacid with at least one aliphatic monohydric alcohol]

The (c ₂ ) ester of a chain hydrocarbon group of a tricarboxylic acid having three carboxyl groups, a hydroxy acid, an alkoxy acid or an oxyacid and at least one aliphatic monohydric alcohol may, for example, be a monoester, a diester or a triester.

[(c ₃ ) an ester of a chain hydrocarbyl dicarboxylic acid having two carboxyl groups, a hydroxy acid, an alkoxy acid or an oxyacid with at least one aliphatic monohydric alcohol]

The ester of (c ₃ ) a chain hydrocarbon dicarboxylic acid having two carboxyl groups, a hydroxy acid, an alkoxy acid or an oxyacid with at least one aliphatic monohydric alcohol may, for example, be a monoester or a diester.

[(d ₁ ) Ether of aliphatic monohydric alcohols and aliphatic monohydric alcohols]

The aliphatic monohydric alcohol is as described above, and as the ether of the above aliphatic monohydric alcohol and aliphatic monohydric alcohol, there is a formula (19): R ¹⁹ OR ²⁰ (19) (wherein, R ¹⁹ And a compound wherein R ²⁰ is a chain hydrocarbon group, respectively.

Further, the chain hydrocarbon group is as described above.

[(d ₂ )dialkyl ketone]

The dialkyl ketone is a compound having the following formula (20): R ²¹ COR ²² (20) (wherein R ²¹ and R ²² are each an alkyl group).

[(d ₃ ) ester of fatty acid with aliphatic monohydric alcohol]

The fatty acid and the aliphatic monohydric alcohol are as described above, and as the ester of the above fatty acid and the aliphatic monohydric alcohol, for example, it has the following formula (21): R ²³ COOR ²⁴ (21) (wherein R ²³ and R ²⁴ is a compound of a chain hydrocarbon group, respectively.

Further, the chain hydrocarbon group is as described above.

[(d ₄ )Dialkyl carbonate]

The dialkyl carbonate is exemplified by the following formula (22): R ²⁵ OC(=O)OR ²⁶ (22) (wherein R ²⁵ and R ²⁶ are each an alkyl group).

[(e ₁ ) polyoxy C ₃ ~C ₆ alkanediol]

The above polyoxy C ₃ -C ₆ alkanediol means i) having an oxy C ₃ -C ₆ alkylene skeleton, that is, having an oxypropylene skeleton, an oxybutene skeleton, an oxypentene skeleton, and Any one of a skeleton in which a oxyhexene skeleton is grouped, and a homopolymer having a hydroxyl group at both terminals, ii) having two or more kinds of skeletons selected from the above group, and having a hydroxyl group at both ends A segment copolymer, or iii) a random copolymer having two or more skeletons selected from the above group and having a hydroxyl group at both terminals.

The polyoxy C ₃ -C ₆ alkanediol is represented by the following formula (23): HO-(C _m H _2m O) _n -H (23) (wherein m is an integer of 3 to 6).

[(e ₂ ) an ester of polyoxy C ₃ -C ₆ alkanediol with at least one fatty acid]

Examples of the polyoxy C ₃ ~ C ₆ alkylene glycol and at least one ester of fatty acid, there are mentioned "(e ₁₎ polyoxy C ₃ ~ C ₆ alkanediol" as described in Paragraph C ₃ ~ polyoxy One or both of the OH ends of the C ₆ alkanediol are esterified with a fatty acid, that is, a monoester and a diester.

Further, the fatty acid is as described above.

[(e ₃ ) an ether of a polyoxy C ₃ -C ₆ alkanediol and at least one aliphatic monohydric alcohol]

The polyoxy C ₃ -C ₆ alkanediol and at least one aliphatic monohydric alcohol are exemplified by the "(e ₁ ) polyoxy C ₃ -C ₆ alkanediol". One or both of the OH ends of the oxygen C ₃ -C ₆ alkanediol are etherified with an aliphatic monohydric alcohol, that is, a monoether and a diether.

Further, regarding the aliphatic monohydric alcohol, it is as described above.

The action of the body fluid slip imparting agent is as described in the specification of International Publication No. 2012/133724 and the specification of International Publication No. 2013/129236. However, when the colloidal emulsion contains a body fluid slip imparting agent as an emulsion, it can be further obtained. The following effects.

The above colloidal emulsion continuously releases the body fluid slip imparting agent to the skin contact area of the absorbent article, for example, because it is slowly released, even if the body fluid slip imparting agent slides down into the absorbent article together with the body fluid, the new body fluid The slip imparting agent is also supplied from the colloidal emulsion to the surface of the liquid permeable layer, and the body fluid continues to slide down into the interior of the absorbent article. As a result, even when the absorbent article is continuously used for a long period of time, the liquid permeable layer is less likely to have a sticky feeling, and the liquid permeable layer continues to be in a dry state.

The above emulsion preferably contains 0 to 50% by mass, more preferably 0 to 40% by mass, and still more preferably 0 to 30% by mass of the above-mentioned body fluid slip imparting agent. This is because of the idea of colloid formation.

100 masses based on the total of these colloidal emulsions Preferably, the amount is preferably from 1 to 30 parts by mass and from 70 to 99 parts by mass, more preferably from 2 to 20 parts by mass and from 80 to 98 parts by mass, and more preferably from 3 to 15 parts by mass and from 85 to 97 parts by weight. The ratio of parts by mass comprises a colloidizing agent and an emulsion. When the ratio of the above colloidizing agent is less than 1 part by mass, the formed colloidal emulsion may have difficulty in functioning as an elastomer or may be deformed when the body pressure is applied, which exceeds the elastic limit of the colloidal emulsion. When the ratio of the above colloidalizing agent exceeds 30 parts by mass, the elasticity of the formed colloidal emulsion becomes high, and the feeling of use may be deteriorated.

The colloidal emulsion preferably has a compressive stress at 50% deformation of 1 to 100 kPa, more preferably a compressive stress at 50% deformation of 1 to 80 kPa, and more preferably 50% deformation at 1.5 to 60 kPa. Compressive stress.

When the compressive stress at 50% deformation is less than 1 kPa, when the body pressure is applied, the colloidal emulsion is deformed beyond the elastic limit and is broken, and if the compressive stress at 50% deformation exceeds 100 kPa, the colloidal emulsion is The elasticity will become high, and the colloidal emulsion will be difficult to deform when the body pressure is applied, and the user will perceive the feeling of discomfort.

Conventional emulsion coatings, skin care agents, and the like, in order to fix an active ingredient in a specific place, a method of making such a high viscosity (viscosity) is employed. However, after such high viscosity, the active ingredient (softener, etc.) is locked inside the emulsion coating, the skin care agent, etc., and it becomes difficult to exert its function. In addition, conventional emulsion coatings, skin care agents, and the like are only viscous bodies. If a body pressure such as pressure is applied, there is a certain place where it is not fixed, and it is moved inside the absorbent article, and it is difficult to continue to act on the skin of the user. Problems.

On the other hand, the above colloidal emulsion exhibits the function as an elastomer in the range of application of body pressure or the like. Therefore, even if a high body pressure is applied to the above-mentioned colloidal emulsion, it does not stay at the elastic deformation all the time, and is not pressed between the fibers of the top sheet, etc., and after the body pressure becomes low, the elasticity regains, And return to the original position (skin contact area). Therefore, the emulsion contained in the colloidal emulsion can achieve its effect in the desired position.

In the present specification, the compressive stress at the time of 50% deformation of the colloidal emulsion is measured as described below.

Further, the item which is not specified is the "compressive stress at 3.7 x% deformation" according to JIS K 7181:2011 "Method for Deriving Plastic-Compression Characteristics".

(1) A compression tester was prepared in a constant temperature and humidity chamber at 20 ° C and 65% RH.

Further, in the present embodiment, a small table type tester EzTest (manufactured by Shimadzu Corporation) was used as the compression tester.

(2) A mold for compression is mounted on a compression tester.

Further, in the present embodiment, a stainless steel compression mold having a diameter of 120 mm was used.

(3) A colloidal emulsion is placed in a mold for compression.

Further, in the present embodiment, a cylindrical colloidal emulsion having a diameter of 40 mm and a height of 8 mm was prepared.

(4) The colloidal emulsion was compressed at a compression speed of 5 mm/min. to a compression amount of 4 mm, that is, a deformation of 50%, and the compression force (N) was read.

(5) The compression force (N) is converted into a compressive stress (Pa).

Moreover, the compressive stress was carried out with a different sample and the average of the three measured values was used.

[anti-wear agent]

The above colloidal emulsion can further contain an anti-wear agent in addition to the colloidizing agent and the emulsion. Examples of the antiwear agent include eucalyptus oil, an anthracene resin, an alkyl acrylate copolymer, a surfactant, a long-chain aliphatic ester, and the like. By including an anti-wear agent, the colloidal emulsion can be expected to have less friction between the colloidal emulsion and the skin of the user when it is used, and the skin of the user is less likely to have a rash effect.

The above colloidal emulsion preferably has a static friction coefficient of from 0.01 to 1.00, more preferably from 0.02 to 0.50, and still more preferably from 0.03 to 0.03. This is based on the point of view that the user's skin is more difficult to rash.

In order to achieve the static friction coefficient, the colloidal emulsion is preferably 0.01 to 20 parts by mass, more preferably 0.05 to 10 parts by mass, per 100 parts by mass of the colloidal emulsion (100 parts by mass of the colloidal agent and the emulsion). Further preferably, the above anti-wear agent is contained in an amount of 0.1 to 7 parts by mass.

The above static friction coefficient was measured as described below. Further, the measurement was carried out in a constant temperature and humidity chamber at 20 ° C × 65% RH.

(1) A cylindrical colloidal emulsion having a diameter of 40 mm and a height of 8 mm was prepared.

(2) As a static friction tester, a HEIDON friction measuring machine μ s (MUSE) TYPE: 94i (hereinafter sometimes referred to as "MUSE") is prepared.

(3) The body of MUSE has a device slider.

(4) Turn on the power of MUSE and confirm that the display is "0.00".

(5) Mount the MUSE slider on the colloidal emulsion.

(6) Press the MUSE measurement button to read the displayed value.

(7) The measurement was carried out 5 times in a different colloidal emulsion, and the average value of these was used.

The above colloidal emulsion can contain other components within a range that does not impair the effects of the present invention.

Examples of the other components include antioxidants such as BHT (2,6-di-t-butyl-p-cresol), BHA (butylated methoxyphenol), and propyl gallate.

As the other ingredients mentioned above, for example, vitamins such as natural vitamins or synthetic vitamins are mentioned. As the above vitamins, for example, water-soluble vitamins such as vitamin B group, such as vitamin B ₁ , vitamin B ₂ , vitamin B ₃ , vitamin B ₅ , vitamin B ₆ , vitamin B ₇ , vitamin B ₉ , vitamin B _{12 ,} etc., vitamins C.

As the above-mentioned vitamins, for example, fat-soluble vitamins such as a vitamin A group, a vitamin D group, a vitamin E group, and a vitamin K group are mentioned.

These vitamins also contain such derivatives.

As the above other components, for example, an amino acid such as alanine, aspartame, lysine, histidine, proline, hydroquinone, or the like, and a peptide are mentioned.

As the above other components, for example, zeolites such as natural zeolites such as analcime, chabazite, stilbite, sodium zeolite, zeolite, and Rodamosonite, and synthetic zeolite.

Examples of the at least one other component include cholesterol, hyaluronic acid, lecithin, and neural amide.

Further, examples of the other components include a drug such as a skin astringent, an anti-cree agent, an anti-wrinkle agent, a subcutaneous fat, a whitening agent, an antibacterial agent, and an antifungal agent.

Examples of the skin astringent agent include oil-soluble skin astringents such as zinc oxide, aluminum sulfate, and tannic acid, and oil-soluble polyphenols. Examples of the oil-soluble polyphenol include natural oil-soluble polyphenols such as cork bark extract, hypericum extract, castor extract, chamomile extract, burdock extract, sage extract, and linden extract. , linden extract, birch extract, squid extract, sage extract, sage extract, peony extract, wood extract, eucalyptus extract, eucalyptus extract, Hop extract, sweet chestnut extract, coix seed extract, etc.

Examples of the anti-acne agent include salicylic acid, benzammonium peroxide, resorcinol, sulfur, erythromycin, zinc, and the like.

Examples of the anti-wrinkle agent include lactic acid, salicylic acid, a salicylic acid derivative, glycolic acid, phytic acid, lipoic acid, and isophosphatidic acid.

As the above-mentioned subcutaneous fat-reducing agent, for example, a xanthine compound such as aminylline, caffeine, theophylline, theobromine or the like can be mentioned.

As the above whitening agent, for example, nicotinic acid, citric acid, arbutin, glucosamine and derivatives, phytosterol derivatives, ascorbic acid and derivatives thereof, and mulberry extract and placenta extract are mentioned.

Further, examples of the other components include an anti-inflammatory component, a pH adjuster, an antibacterial agent, a moisturizer, and a fragrance such as a flavor oil, a coloring matter, a dye, a pigment, and a plant extract. As the anti-inflammatory component, for example, natural anti-inflammatory agents such as peony, scutellaria, hypericum, chamomile, licorice, peach, wormwood, perilla extract, etc., synthetic anti-inflammatory agents such as allantoin, licorice Dipotassium acid and the like.

As the pH adjuster, there are mentioned those used to keep the skin weakly acidic, such as malic acid, succinic acid, citric acid, tartaric acid, lactic acid and the like.

As the above pigment, for example, titanium oxide is mentioned.

Further, as the other components mentioned above, there are those having a skin care function, such as jojoba oil, bitter tea oil, and squalane oil.

Further, as the other components mentioned above, petroleum is mentioned.

In the absorbent article of the present invention, the liquid permeable layer has a plurality of colloidal regions having the colloidal emulsion and a non-colloidal region having no colloidal emulsion in the skin contact region, and in the skin non-contact region And a plurality of colloidal region repeating domains and non-colloidal region repeating domains respectively repeating in the thickness direction with the plurality of colloidal regions and the non-colloidal regions.

Fig. 1 is a plan view showing an absorbent article 1 according to an embodiment of the present invention. The absorbent article 1 shown in Fig. 1, more specifically, the sanitary napkin has a top sheet 2 as a liquid permeable layer, a bottom sheet as a liquid impermeable layer (not shown), and a top portion. An absorbent body 3 serving as an absorbent layer between the sheet 2 and the bottom sheet (not shown). The absorbent article 1 shown in Fig. 1 also has a side sheet 4 and a pressure Printing section 5. In the absorbent article 1 shown in Fig. 1, the liquid-permeable top sheet 2 has, in the skin contact region 7, a plurality of colloidal regions 8 having a colloidal emulsion 6 and a non-colloidal region 9 having no colloidal emulsion.

In the absorbent article 1 shown in Fig. 1, a plurality of linear colloidal emulsions 6 are continuously applied along the longitudinal direction of the absorbent article 1. In other words, the top sheet 2 has a plurality of linear colloidal regions 8 which are parallel to each other and continuously extend in the longitudinal direction of the absorbent article 1.

2 is a cross-sectional view taken along line II-II of the area A of FIG. 1, and for the sake of explanation, is a view showing only the top sheet 2. In Fig. 2, the top sheet 2 has in the skin contact region 7 a plurality of colloidal regions 8 having a colloidal emulsion 6 and a non-colloidal region 9 having no colloidal emulsion, and having a plurality of colloids in the skin non-contacting region 10, respectively. The region 8 and the non-colloidal region 9 repeat the domain 11 and the non-colloidal region repeating domain 12 in a plurality of colloidal region repeats in the thickness direction T.

In Fig. 2, in the two colloidal regions 8' and 8" adjacent to each other, two adjacent points 13' and 13" of the two closest colloidal regions 8' and 8" adjacent to each other, and In the middle of the two adjacent points 13' and 13" and the intermediate point 14' of the non-colloidal region 9', and the two adjacent points 13' and 13" are repeated in the thickness direction T and there is a colloidal region repeating domain 11 respectively. The two adjacent points of 'and 11' correspond to points 15' and 15", and the intermediate point 14' is repeated in the thickness direction T and exists in the middle point of the non-colloidal region repeating field 12'. The point 16' has i)~iii Relationship: i) Both water contact angles of the two adjacent points 13' and 13" are above 85°, Ii) the water contact angle in the intermediate point 14' is greater than the water contact angle in the point 15' and 15" of the two adjacent points, and iii) the water contact angle of the intermediate point 14' is in the point 16' of the intermediate point The difference in water contact angle is larger than -3 (°).

Since both of the water contact angles of the two adjacent points 13' and 13" are 85 or more, it is difficult for the body fluid to remain on the top sheet 2.

Moreover, the water contact angle in the intermediate point 14 is greater than the water contact angle in the corresponding points 15' and 15" of the two adjacent points, and the water contact angle with the intermediate point 14 is in contact with the water in the intermediate point corresponding point 16. The difference in angle is larger than -3 (°). From the non-contact area 10 of the skin to the skin contact area 7, the water contact angle will gradually become larger, that is, the hydrophobicity will gradually become higher, once It is difficult for the body fluid absorbed into the absorbent body to pass through the top sheet 2 to reach the skin contact region 7. That is, the rewet is excellent.

In the absorbent article of the present invention, i) the water contact angles of the two adjacent points are both 85 or more, and preferably both are 90 or more, and more preferably both are 100 or more. The water contact angle of the two adjacent points is preferably 150 or less, and more preferably 140 or less. This is because the permeability of the liquid permeable layer of the body fluid can be maintained and the rewet can be improved.

Further, in the absorbent article of the present invention, ii) the water contact angle in the intermediate point is larger than the water contact angle in the point corresponding to the two adjacent points, preferably 5° or more, and more preferably 10° or more. . The water contact angle in the intermediate point is preferably 50° or less larger than the water contact angle in the point corresponding to the two adjacent points, and the range of 30° or less is more preferable. This is to keep the liquid of the body fluid through The permeability of the layer also increases the gradient of the hydrophobicity of the liquid permeable layer and improves the rewet.

Further, in the absorbent article of the present invention, iii) the difference between the water contact angle of the intermediate point and the water contact angle in the point corresponding to the intermediate point is larger than -3°, preferably larger than -1°, and more preferably Larger than 3°. The difference in water contact angle between the water contact angle at the intermediate point and the intermediate point is preferably 30 or less, and more preferably 10 or less. This is based on the absorption rate of the body fluid and the fact that it is difficult for the body fluid to remain in the liquid permeable layer.

In the absorbent article of the present invention, in the plurality of colloidal regions, at least a portion of the two adjacent colloidal regions have the relationship of i) to iii), and the combination of the two colloidal regions adjacent to each other is preferably 20% or more, more preferably 40% or more, and still more preferably 60% or more has the relationship of the above i) to iii). This is in view of the effects of the present invention.

In the absorbent article of the present invention, it is preferable to have the above relationship i) to iii) in the contact excretion opening region. This is from the viewpoint of the effects of the present invention.

Fig. 3 is a schematic view for explaining the effects of the present invention. Figure 3 is a cross-sectional view taken along line II-II of the area A of Figure 1. As shown in FIG. 3, the emulsion 17 exuded from the colloidal emulsion 6 diffuses from the colloidal emulsion 6 in the plane direction P and the thickness direction T with time, and the two adjacent points 13 are related to the basis weight and arrangement of the colloidal emulsion 6. The water contact angle of the intermediate point 14, the adjacent point corresponding point 15 and the intermediate point corresponding point 16 satisfy the above requirements, and has the effect of the present invention.

In the present specification, the water contact angle is measured as follows.

(1) Prepare a contact angle meter made by the Concord Interface Scientific in a thermostatic chamber at 20 °C.

(2) The sample to be measured was allowed to stand in the above-mentioned constant temperature room for 24 hours.

(3) Drop 5 drops (distilled water) at the point where the sample to be measured should be measured.

(4) The water contact angle was measured after dropping for 5 seconds.

(5) The samples were counted 10 times in the same manner, and the average value was used.

In the embodiment shown in Fig. 1, a plurality of colloidal regions 8 (colloidal emulsions 6) are parallel to each other and extend in the longitudinal direction of the absorbent article 1, so that the straight lines connecting the two adjacent points with the intermediate points form a colloidal region. 8 vertical lines. Moreover, the straight line connecting the two adjacent points and the point corresponding to the intermediate point also forms a vertical line of the colloidal region 8.

Fig. 4 is a plan view showing an absorbent article 1 according to an embodiment of the present invention. In the absorbent article 1 shown in Fig. 4, more specifically, in a sanitary napkin, the top sheet 2 contains a colloidal emulsion 6 in its skin contact region 7, and a plurality of point-like colloidal emulsions 6 are coated in a thousand birds. In other words, the top sheet 2 contains a plurality of point-like colloidal emulsions 6 arranged in a thousand bird shape.

Fig. 5 is an enlarged view of a region A of Fig. 4. In Fig. 5, two adjacent points 13' and 13", the intermediate point 14', and two adjacent points 13 of the points closest to each other in the two adjacent colloidal regions 8' and 8" are shown. 'and 13' are repeated in the thickness direction and exist in the colloidal region repeating domain (not shown) at two adjacent points corresponding to points 15' and 15", and The intermediate point 14' is repeated in the thickness direction and exists at the intermediate point of the non-colloidal region repeating region (not shown) corresponding to the point 16'.

Fig. 6 is a plan view showing an absorbent article 1 according to an embodiment of the present invention, which corresponds to a region A of Fig. 4. The absorbent article 1 shown in Fig. 6 contains a colloidal emulsion 6 in the skin contact region 7 of the top sheet 2, and a plurality of linear colloidal emulsions 6 are applied at intervals in the longitudinal direction of the absorbent article 1. In other words, the top sheet 2 contains a plurality of linear colloidal emulsions 6 which are parallel to each other and which extend in the longitudinal direction of the absorbent article 1 at intervals.

Also shown in Fig. 6 are two adjacent points 13' and 13" of the two closest colloidal regions 8' and 8" adjacent to each other, and intermediate points 14' and 2 adjacent points. The two adjacent points of 13' and 13" which are repeated in the thickness direction and exist in the colloidal region repeating region (not shown) are equivalent to points 15' and 15", and overlap with the intermediate point 14' in the thickness direction and exist in the non- The intermediate point of the colloidal region repeating domain (not shown) is equivalent to 16'.

In the absorbent article of the present invention, the colloidal region having the colloidal emulsion is disposed so as to satisfy the relationship of the above i) to iii), and is not particularly limited. For example, the colloidal region is configured as a line in the skin contact region of the liquid permeable layer. Shape or point.

In the above colloidal region, in the range in which the liquid permeable layer is repeated in the thickness direction of the absorbent layer and the absorbent article, the area of the liquid permeable layer preferably accounts for 1 to 50%, and more preferably 3 to 40%. More preferably, it occupies 5 to 30% of the area.

If the area of the liquid permeable layer in the above-mentioned colloidal region is less than 1%, the effect of the present invention tends to be difficult to exhibit. When the area of the liquid permeable layer in the colloidal region is more than 50%, the colloidal region does not absorb the body fluid, and as a result, the region in which the body fluid is absorbed becomes narrow, and the absorbability of the absorbent article tends to decrease.

Further, in order to achieve the coating region, the liquid permeable layer is preferably in the range of 1 to 30 g/m ² , more preferably 2 to 20 g/m ² , in the range in which the absorbent layer and the absorbent article are repeated in the thickness direction. More preferably, the above colloidal emulsion is contained at a basis weight of 3 to 10 g/m ² .

In the present specification, the basis weight of the colloidal emulsion is measured as follows.

(1) The range to be measured of the top sheet is cut out with a sharp cutter such as a replacement piece of the blade to obtain a sample.

(2) Area of sample: Determination of S (m ² ) and mass: M ₀ (g).

(3) The sample is stirred at least for 3 minutes in a solvent in which the colloidal emulsion is soluble, for example, an aromatic solvent such as xylene, and the colloidal emulsion is dissolved in the solvent.

(4) The sample was filtered on a filter paper of a measured mass, and the sample was thoroughly washed with a solvent on a filter paper. The sample on the filter paper was dried in an oven at 100 °C.

(5) The mass of the filter paper and the sample were measured, and the mass of the dried sample was calculated by subtracting the mass of the filter paper: M ₁ (g).

(6) The basis weight G _BW (g/m ² ) of the colloidal emulsion is given by the following formula: G _BW (g/m ² ) = [M ₀ (g) - M ₁ (g)] / S (m ² ) Calculated.

Further, in order to reduce the error, a plurality of samples were taken from the complex absorbent article so that the total area of the sample exceeded 100 cm ² , and the experiment was repeated for a plurality of experiments, and the average value thereof was used.

In the absorbent article of the present invention, when the liquid permeable layer is a nonwoven fabric or a woven fabric, the nonwoven fabric or woven fabric is preferably hydrophilized. Examples of the hydrophilization treatment include a hydrophilic agent added to a surface of a nonwoven fabric or a woven fabric, and a hydrophilic agent or the like is added to a synthetic resin of a raw material of a nonwoven fabric or a woven fabric. The lipophilic region derived from a hydrocarbon, a body fluid slip imparting agent or the like and the hydrophilic region derived from the hydrophilic agent are sparsely supplied to the liquid permeable layer because the sliding property is more exhibited and the body fluid is easily moved to the body fluid easily Absorber.

The above colloidal emulsion can be produced without particular limitation.

For example, a coating liquid can be produced by adding a colloidizing agent to the heated emulsion, followed by mixing, and the coating liquid can be applied to the liquid permeable layer of the absorbent article to which the colloidal emulsion is applied, thereby producing an absorbent article. .

The colloidal emulsion can be applied as a coating liquid containing a volatile solvent, for example, an alcohol-based solvent, an ester-based solvent, or an aromatic solvent, as desired. When the coating liquid contains a volatile solvent, the viscosity of the coating liquid is lowered, and the coating step can be easily performed, and the coating step such as heating at the time of coating is not required to be simplified.

The coating method of the coating liquid is not particularly limited, and the coating liquid can be heated as necessary, and then, for example, a non-contact coater or contact. Coating is performed by a coater or the like.

Examples of the non-contact type coater include a spiral coater, a curtain coater, a spray coater, and a dipping coater. Examples of the contact coater include a slot coater. , graphic coater, etc.

The coating liquid can be applied to a material for producing a liquid permeable layer, for example, when it is not woven, or can be applied to an absorbent article to which a colloidal emulsion is applied in a production line for producing an absorbent article. From the viewpoint of suppressing equipment investment, it is preferable to apply the above coating liquid in the production line of the absorbent article, and further, to suppress the colloidal emulsion from falling off and contaminating the production line, in the downstream step of the production line, specifically, sealing the product to It is preferred to apply the above coating liquid before packaging.

Examples of the absorbent article of the present invention include disposable diapers, incontinence pads, sanitary napkins, and pads.

[Examples]

Hereinafter, the present invention will be described by way of examples, but the present invention is not limited thereto.

[example 1]

2 parts of SEPS (styrene content: 20% by mass, weight average molecular weight: about 260,000) (hereinafter sometimes referred to as "SEPS-1") and SEBS (styrene content: 31% by mass, weight average molecular weight: about 16 10,000) (hereinafter sometimes referred to as "SEBS-2") 5 parts added to PARLEAM 6 heated to about 140 ° C (made by Nippon Oil Co., Ltd., by copolymerization of flowing isoalkanes, isobutylene and n-butene, followed by addition Branched hydrocarbon formed by hydrogen formation, degree of polymerization: about 5 to about 10, weight average molecular weight: about 330) 90 parts with eucalyptus oil (SHW-100cs, dimethyl polyoxane, manufactured by Dow Corning Toray Co., Ltd., 25 In a mixture of 3 parts of the dynamic viscosity at ° C of 100 mm ² /s), the mixture was mixed for 5 hours while stirring to form a mixture, as shown in Fig. 1, applied to the skin of the top sheet of the absorbent article. On the contact area, the absorbent article No. 1-1 was obtained. In the absorbent article No. 1-1, the width of the colloidal region was 2 mm, the pitch was 4 mm, and the basis weight of the colloidal emulsion was 30 g/m ² . Further, the top sheet of the absorbent article No. 1-1 was a breathable nonwoven fabric having a basis weight of 25 g/m ² (hereinafter referred to as "nonwoven fabric A").

The basis weight of the colloidal emulsion and the top sheet of the absorbent article were changed to the same as those of the absorbent article No. 1-1 except that the top sheet of the absorbent article was changed to obtain absorbent articles No. 1-2 and 1-3. Further, the top sheets of the absorbent articles No. 1-2 and 1-3 are air-permeable nonwoven fabrics having a basis weight of 27 g/m ² (hereinafter referred to as "non-woven fabric B").

The blending and the basis weight of the colloidal emulsion were changed to those shown in Table 2, and the absorbent article No. 1-4 was obtained in the same manner as in the absorbent article No. 1-1.

The basis weight of the colloidal emulsion and the coating pattern were changed as shown in Table 2, and the same as the absorbent article No. 1-1, the absorbent article No. 1-5 (comparative sample) and 1-6 (comparative) were obtained. Use the sample).

A sample without a coated colloidal emulsion was used as the absorbent article No. 1-7 (Comparative sample) and 1-8 (comparative sample) are used.

[water contact angle]

The water contact angle was evaluated for the absorbent articles No. 1-1 to 1-8. The results are compiled and shown in Table 2.

[Absorber migration speed and rewet]

With respect to the absorbent articles No. 1-1 to 1-8, the absorbent body migration speed and rewet property were measured as described below.

Place a propylene cylinder on the top sheet of the absorbent article (outer diameter 60mm) , inner diameter 55mm 55g), using a dropping funnel in the above-mentioned cylinder, artificial urine (200 g of urea, 80 g of sodium chloride, 8 g of magnesium sulfate, 3 g of calcium chloride, and about 1 g of dye: blue No. 1 are dissolved in 10 L of ion-exchanged water) 80 mL of the prepared solution was dropped at a rate of 8 mL/second (the first drop).

The time from when the artificial urine was dropped in the cylinder until the artificial urine remaining in the cylinder disappeared was measured as the "absorbent migration speed". Then, after the artificial urine in the cylinder disappeared, the acrylic cylinder was removed, and 5 minutes after the first dripping, the filter paper was placed at the place where the artificial urine was dropped (ADVANTEC Toyo Co., Ltd., qualitative filter paper) No. 2, 100 mm × 100 mm) A 50 g portion, and a load reset pressure was placed thereon to be 35 g/cm ² . After 3 minutes, the filter paper was taken out, and the "rewetting amount" was calculated according to the following formula.

Rewetting amount (g) = quality of filter paper after test (g) - quality of original filter paper (g)

Ten minutes after the start of the first drop, the same operation as in the first time was repeated, and the second drop was performed.

The rewetting amount in the second dropping and the moving speed of the absorbent in the second dropping were adjusted and shown in Table 2.

It was found that the absorbent articles No. 1-1 to 1-4 were lower in rewetting rate and more excellent in rewet than the absorbent articles No. 1-5 to 1-8.

[Example 2]

SEEPS (Septon 4055, manufactured by Kuraray Co., Ltd., styrene content: 30% by mass, weight average molecular weight: about 250,000) (hereinafter sometimes omitted "SEEPS-2") was added to PARLEAM EX heated to about 140 °C. (manufactured by Nippon Oil Co., Ltd., by copolymerizing a flow of isoparaffin, isobutylene, and n-butene, followed by addition of hydrogen to form a branched hydrocarbon, a dynamic viscosity at 107.8 ° C of 10 mm ² /s) 98 parts, The mixture was mixed while stirring for 5 hours to form a mixture, and the mixture was poured into a cylindrical container having a diameter of 40 mm to a height of 8 mm, and then the mixture was cooled, thereby obtaining a cylinder having a diameter of 40 mm and a height of 8 mm. Colloidal emulsion No. 2-1.

3 parts of SEPS-1 was added to a mixture of 92 parts of PARLEAM EX heated to about 140 ° C and 5 parts of eucalyptus oil, and the mixture was stirred while stirring for 5 hours to form a mixture, and the subsequent product was injected into a circle having a diameter of 40 mm. The cylindrical container was allowed to have a height of 8 mm, and then the mixture was cooled, whereby a cylindrical colloidal emulsion No. 2-6 having a diameter of 40 mm and a height of 8 mm was obtained.

The colloidal emulsion No. 2-2 to 2-5 and No. 2-7 to 2 were obtained in the same manner as the colloidal emulsion No. 2-1 or the colloidal emulsion No. 2-6 except that the blending was changed to that shown in Table 3. -20.

Further, the outlines of the compounds described in Table 3 are as follows, but If it is described elsewhere, the description will be omitted.

Further, the compressive stress and the static friction coefficient at 50% deformation of the colloidal emulsion No. 2-1 to 2-20 were evaluated. Consolidated and shown in Table 3.

. SEEPS-1:

Styrene content: 30% by mass, weight average molecular weight: about 110,000

. SEBS-1:

Styrene content: 30% by mass, weight average molecular weight: about 110,000

. SEBS-2:

Styrene content: 31% by mass, weight average molecular weight: about 160,000

. SEBS-3:

Styrene content: 33% by mass, weight average molecular weight: about 290,000

[Example 3]

The cylindrical colloidal emulsion Nos. 3-1 to 3-4 having a diameter of 40 mm and a height of 8 mm were obtained in the order of the colloidal emulsion No. 2-6 of Production Example 1 in addition to the preparation described in the following Table 4.

Further, the outlines of the compounds described in Table 4 are as follows.

. NONION OP-80R:

Made from Nippon Oil Co., Ltd., oleic acid sorbitan

. KP-561P

Shin-Etsu Chemical Industry Co., Ltd., acrylate/acrylic acid stearin/dimethyl methacrylate copolymer

The static friction coefficient of the colloidal emulsion No. 3-1 to 3-4 was measured. The results are consolidated and shown in Table 4.

[Example 4]

A colloidal emulsion was obtained according to the order of the colloidal emulsion No. 2-1 or No. 2-6 of Production Example 2, except that the amount of 3 g was injected into a glass vessel having an inner diameter of 47 mm according to the formulation described in the following Table 5. No.4-1~4-4.

According to Example 4A of Citation 1, an emulsion composition containing 65% by mass of mineral oil and 35% by mass of cetearyl alcohol was prepared, and an amount of 3 g was poured into a glass vessel having an inner diameter of 47 mm to prepare a colloidal emulsion No. 4- 5 (comparative example).

The colloidal emulsion No. 4-1 to 4-5 was statically placed in a thermostatic chamber at 35 ° C or 20 ° C for 30 minutes, and then a measuring mass of 3 cm × 3 cm filter paper was placed on each colloidal emulsion, and 200 g of the filter paper was placed thereon. The load was removed, and the load was removed after 1 minute, and the change in the quality of the filter paper was measured. The results are shown in Table 5.

It can be clearly seen from Table 5 that the colloidal emulsion No. 4-1 to 4-4 does not release a certain amount of emulsion with temperature change, and it is pointed out that the emulsion can be continuously released in a cold to warm region. .

On the other hand, it was also found that the colloidal emulsion No. 4-5 (comparative example) was difficult to release the emulsion at a low temperature.

The present invention relates to the following J1 to J11.

[J1]

An absorbent article comprising: a liquid permeable layer having a skin contact region and a skin non-contact region; an absorbing layer between the liquid permeable layer and the liquid permeable layer and the liquid opaque layer; a colloidal emulsion having an absorbent article in a thickness direction, wherein the colloidal emulsion contains a styrene-based elastomer as a colloidalizing agent and a hydrocarbon as an emulsion, and the liquid-permeable layer has the skin contact region: a plurality of colloidal regions of the colloidal emulsion and a non-colloidal region having no colloidal emulsion, and having a plurality of colloids respectively overlapping the plurality of colloidal regions and the non-colloidal region in the thickness direction in the non-contact region of the skin a region repeating domain and a non-colloidal region repeating region, wherein in the at least one of the two colloidal regions adjacent to each other, at least two adjacent points of the two colloidal regions adjacent to each other, And an intermediate point between the two adjacent points and the non-colloidal region, and the two adjacent points Repeat and is present in two adjacent points is quite point repeat domains of the colloidal region in the thickness direction, and is present in the non-repeating colloid in the thickness direction of the intermediate point of the The intermediate point of the region repeating region satisfies the following relationship i) to iii) i) the water contact angle of the two adjacent points, both of which are at 85° or more, ii) the water contact angle in the intermediate point is higher than the above two The water contact angle in the point where the adjacent point is large is large, and iii) the difference between the water contact angle of the intermediate point and the water contact angle of the point corresponding to the intermediate point is larger than -3 (°).

[J2]

An absorbent article according to J1, wherein the colloidal emulsion has a compressive stress at 50% deformation of 1 to 100 kPa.

[J3]

In the above-mentioned colloidal emulsion, the colloidal agent and the emulsion are contained in a ratio of 1 to 30 parts by mass and 70 to 99 parts by mass, respectively, based on 100 parts by mass of the total of the above-mentioned colloidal emulsions.

[J4]

The absorbent article according to any one of J1 to J3, wherein the polystyrene block comprises a polyolefin block at both ends and a polyolefin block therebetween.

[J5]

The absorbent article according to any one of the above aspects, wherein the polystyrene block comprises 10 to 50% by mass of a polystyrene block and 50 to 90% by mass of a polyolefin block.

[J6]

The absorbent article according to any one of the above-mentioned, wherein the styrene-based elastomer has a weight average molecular weight of 5,000 to 500,000.

[J7]

The absorbent article of any one of J1 to J6, wherein the above colloidal emulsion further comprises an antiwear agent.

[J8]

The absorbent article according to any one of J1 to J7, wherein the colloidal emulsion has a static friction coefficient of 0.01 to 1.00.

[J9]

The absorbent article according to any one of the aspects of the present invention, further comprising the body fluid slip imparting agent as the emulsion, wherein the body fluid slip imparting agent has an IOB of more than 0.00 and 0.60 or less, and a 0.01% at 40 ° C. The dynamic viscosity of 80 mm ² /s, the water holding ratio of 0.01 to 4.0% by mass, and the weight average molecular weight of less than 1,000.

[J10]

The absorbent article according to any one of the above aspects, wherein the colloidal emulsion is disposed in a line shape or a dot shape in a skin contact region of the liquid permeable layer.

[J11]

An absorbent article according to any one of J1 to J10, which is a disposable diaper, a sanitary napkin or a pad.

Claims (11)

An absorbent article comprising: a liquid permeable layer having a skin contact region and a skin non-contact region; and a liquid impervious layer; and an absorbing layer between the liquid permeable layer and the liquid opaque layer; And a colloidal emulsion having an absorbent article having a thickness direction, wherein the colloidal emulsion comprises a styrene-based elastomer as a colloidizing agent and a hydrocarbon as an emulsion, and the liquid-permeable layer has a skin contact region in the skin contact region: a plurality of colloidal regions having the colloidal emulsion, and a non-colloidal region having no colloidal emulsion, and the plurality of colloids having the colloidal region and the non-colloidal region respectively repeating in the thickness direction in the non-contact region of the skin a region repeating domain and a non-colloidal region repeating region, wherein at least a part of the two colloidal regions adjacent to each other among the plurality of colloidal regions, two adjacent points of the two adjacent colloidal regions are adjacent to each other In the middle of the two adjacent points, and present in the middle point of the non-colloidal region, and the two The two adjacent points of the contact point which are repeated in the thickness direction and exist in the repeating domain of the colloid region are equivalent to the intermediate point of the intermediate point which is repeated in the thickness direction and which exists in the repeating domain of the non-colloidal region. Relationship between i) and iii) i) water contact angles of two adjacent points, both of which are 85° or more, ii) the water contact angle of the intermediate point is larger than the water contact angle of the two adjacent points And iii) the water contact angle of the aforementioned intermediate point is equal to the water of the aforementioned intermediate point The difference in contact angle is larger than -3 (°). The absorbent article according to claim 1, wherein the colloidal emulsion has a compressive stress at 50% deformation of 1 to 100 kPa. The absorbent article according to claim 1 or 2, wherein the colloidal emulsion contains the colloidalizing agent and the emulsion in a ratio of 1 to 30 parts by mass and 70 to 99 parts by mass based on 100 parts by mass in total. The absorbent article of claim 1 or 2, wherein the polystyrene block comprises a polystyrene block at both ends and a polyolefin block therebetween. The absorbent article according to claim 1 or 2, wherein the polystyrene block comprises 10 to 50% by mass of a polystyrene block and 50 to 90% by mass of a polyolefin block. The absorbent article of claim 1 or 2, wherein the styrene-based elastomer has a weight average molecular weight of 5,000 to 500,000. The absorbent article of claim 1 or 2, wherein the aforementioned colloidal emulsion further comprises an anti-wear agent. The absorbent article of claim 1 or 2, wherein the aforementioned colloidal emulsion has a static friction coefficient of 0.01 to 1.00. The absorbent article according to claim 1 or 2, further comprising a body fluid slip imparting agent as the emulsion, the body fluid slip imparting agent having an IOB of more than 0.00 and 0.60 or less, and 0.01 to 80 mm ^{2 at} 40 ° C / The dynamic viscosity of s, the water holding ratio of 0.01 to 4.0% by mass, and the weight average molecular weight of less than 1,000. The absorbent article of claim 1 or 2, wherein the aforementioned colloid The emulsion is disposed in a line shape or a dot shape in the skin contact region of the liquid permeable layer. The absorbent article of claim 1 or 2, which is a disposable diaper, a sanitary napkin or a pad.