JP2015066383A - Absorbent article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an absorbent article having improved liquid migration from a top sheet to an absorber.SOLUTION: An absorbent article 1 comprises a top sheet 2, a back sheet 3 and an absorber 4. The absorber 4 comprises an absorbent core 41, a top-sheet side cover sheet 42, a back-sheet side cover sheet 43, and a compression recess 45 formed by compressing the back-sheet side cover sheet 43 to a direction of the absorbent core 41. The compression recess 45 has a low compression recess 452 which is a mesh-like pattern, and a high compression recess 451 formed to be scattered in the mesh-like pattern. When a low fiber density region 22 and the low compression recess 452 are projected onto a virtual plane P perpendicular to a thickness direction Z, the projection region of the low fiber density region 22 has an overlap with the projection region of the low compression recess 452.

Description

  The present invention relates to an absorbent article.

  Various techniques for improving the feeling of use have been developed for absorbent articles such as sanitary napkins.

  As one of the techniques, formation of a ridge and a groove on the top sheet (Patent Documents 1 and 2) is known. In Patent Documents 1 and 2, the fiber density in the central region of the buttock is set to a substantially uniform fiber density lower than the average fiber density of the entire buttock, and the fiber density in the side edge region of the buttock is set to A substantially uniform fiber density that is higher than the overall average fiber density is used. Thereby, the menstrual blood transfer property from the center area | region of a buttocks to an absorber improves. In addition, since the contact area between the user's skin and the top sheet is reduced by the buttocks and the grooves, even if the menstrual blood once absorbed by the absorbent body returns to the top sheet, the reverted menstrual blood remains in the user's skin. It is hard to adhere to. Furthermore, even if force is applied to the buttocks, the center region is supported by the side edge region of the buttocks, so that the buttocks are not easily crushed.

  As another technique, formation of a compressed recess in an absorbent body (Patent Document 3) is known. In patent document 3, the compression recessed part which consists of the high pressing recessed part which is scattered and the low pressing recessed part which connects the scattered high pressing recessed part is formed in an absorber. Thereby, the rigidity of an absorber improves and generation | occurrence | production of the twist of an absorbent article is prevented.

As yet another technique, a blood slipperiness imparting agent having a kinematic viscosity at 40 ° C. of 0.01 to 80 mm ² / s, a water retention of 0.01 to 4.0% by mass, and a weight average molecular weight of less than 1,000. Application to a top sheet is known (Patent Document 4). In patent document 4, the menstrual blood transfer property from a top sheet to an absorber is improved with a blood slipperiness | lubricity imparting agent. Thereby, the sticky feeling resulting from menstrual blood remaining in the top sheet is prevented.

JP 2008-23326 A JP 2008-25079 A JP 2013-78366 A JP 2013-179982 A

  An object of this invention is to provide the absorbent article which has the improved liquid transferability from a top sheet to an absorber.

  In order to solve the above problems, the present invention has a transverse direction, a longitudinal direction and a thickness direction orthogonal to each other, a liquid-permeable top sheet, a liquid-impermeable back sheet, the top sheet, An absorbent article comprising an absorbent body provided between back sheets, wherein the top sheet is a nonwoven fabric having a high fiber density region and a low fiber density region, and the absorbent body comprises absorbent fibers. An absorptive core containing, a topsheet side covering sheet for covering the topsheet side surface of the absorbent core, a backsheet side covering sheet for covering the backsheet side surface of the absorbent core, and the backsheet side covering A pressing recess formed by pressing the sheet toward the absorbent core, and the pressing recess is a low-pressure pressing recess formed in a mesh pattern. , And the high pressing depressions formed so as to be scattered in the mesh pattern, and the low fiber density region and the low pressing depression are projected onto a virtual plane perpendicular to the thickness direction. When providing the absorbent article, the projection region of the low fiber density region has an overlap with the projection region of the low-pressure depression.

  ADVANTAGE OF THE INVENTION According to this invention, the absorbent article which has the improved liquid transferability from a top sheet to an absorber is provided.

FIG. 1 is a partially broken plan view of a sanitary napkin according to an embodiment of the absorbent article of the present invention. FIG. 2 is an enlarged cross-sectional view taken along line AA in FIG. FIG. 3 is an enlarged sectional view taken along line BB in FIG. FIG. 4 is an enlarged perspective view of a part of the top sheet included in the sanitary napkin shown in FIG. 1. FIG. 5 is a plan view of the back sheet side surface of the absorbent body included in the sanitary napkin shown in FIG. 1. FIG. 6 is an enlarged view of a portion indicated by C in FIG. FIG. 7 is a projection area of a groove portion generated when the groove portion of the top sheet and the low-pressure depression of the absorbent body are projected on a virtual plane perpendicular to the thickness direction of the sanitary napkin in the sanitary napkin shown in FIG. It is a one part enlarged view of a virtual plane which shows the overlap with the projection area | region of a low pressing recessed part.

  The absorbent article of the present invention has a transverse direction, a longitudinal direction, and a thickness direction orthogonal to each other, and a liquid-permeable top sheet, a liquid-impermeable back sheet, and between the top sheet and the back sheet The top sheet is a non-woven fabric having a high fiber density region and a low fiber density region, and the absorber contains an absorptive fiber. A core, a topsheet-side covering sheet that covers the topsheet-side surface of the absorbent core, a backsheet-side covering sheet that covers the backsheet-side surface of the absorbent core, and the absorption of the backsheet-side covering sheet A pressing recess formed by pressing in the direction of the sexual core, the pressing recess being a low-pressure pressing recess formed in a mesh pattern, and the mesh-shaped High depressions formed so as to be scattered in the turn, and when the low fiber density region and the low depressions are projected onto a virtual plane perpendicular to the thickness direction, The projection area of a fiber density area is related with the absorptive article which has an overlap with the projection area of the low-pressure pressing recessed part.

  In the absorbent article of the present invention, “high fiber density” and “low fiber density” mean the relative level of fiber density, and “high pressure” and “low pressure” mean the relative level of compression. means.

  The absorbent article of the present invention can exhibit the following effects. The top sheet is partitioned into a high fiber density region and a low fiber density region in plan view. The liquid is less liable to stay in the low fiber density region than in the high fiber density region, so that the liquid supplied to the top sheet easily moves to the absorbent body through the low fiber density region of the top sheet. The low fiber density region of the top sheet and the low pressing depression of the absorbent body overlap each other so that the projection region of the low fiber density region overlaps with the projection region of the low pressing depression (that is, in the thickness direction of the absorbent article). As such, when the liquid supplied to the top sheet moves to the absorbent body through the low fiber density region of the top sheet, the liquid tends to migrate to the low pressure depression of the absorbent body. Since the low pressure depression of the absorbent body is formed in a mesh pattern, the liquid that has migrated to the low pressure depression of the absorbent body can diffuse along the whole mesh pattern. Therefore, the absorbent article of the present invention can exhibit improved liquid migration from the top sheet to the absorbent body.

  In a preferable aspect (Aspect 1) of the absorbent article of the present invention, 2% or more of the projected area of the low fiber density area overlaps with the projected area of the low-pressure depression. According to the aspect 1, the liquid transferability from the low fiber density region of the top sheet to the low pressure recessed portion of the absorber can be improved.

  In a preferred embodiment (embodiment 2) of the absorbent article of the present invention, the fiber density of the low pressing depression is greater than the fiber density of the low fiber density region. According to the aspect 2, the liquid transfer property from the low fiber density region of the top sheet to the low pressure recessed portion of the absorbent body is obtained by utilizing the property of the liquid that it is easy to transfer from the low fiber density part to the high fiber density part. Can be improved. Note that aspect 2 can be combined with aspect 1.

  In a preferred aspect (Aspect 3) of the absorbent article of the present invention, the fiber density of the high-pressure recessed portion is greater than the fiber density of the high fiber density region. According to the third aspect, the liquid remaining in the low fiber density region and the high fiber density region of the top sheet is used to absorb the liquid remaining in the absorber using the characteristic of the liquid that easily shifts from the low fiber density portion to the high fiber density portion. It can be pulled into the high pressure depression. Aspect 3 can be combined with Aspect 1 and / or Aspect 2.

  In a preferred aspect (Aspect 4) of the absorbent article of the present invention, the top sheet has a flange extending in the longitudinal direction and a groove extending in the longitudinal direction, and the flange Corresponds to the high fiber density region, and the groove corresponds to the low fiber density region. According to the aspect 4, the liquid supplied to the top sheet is likely to spread in the longitudinal direction of the absorbent article along the ridges and the grooves, so that the liquid supplied to the top sheet is reduced in the short direction of the absorbent article. Spreading and leakage from the absorbent article due to this can be prevented. In addition, the aspect 4 can be combined with one of the aspects 1 to 3, or two or more aspects that can be arranged side by side.

  In a preferred aspect (aspect 5) of the absorbent article according to aspect 4, the low-pressure depression has an extending portion extending in the longitudinal direction, and the groove and the low-pressure depression are formed with the thickness. When projected onto a virtual plane perpendicular to the direction, the projection area of the groove has an overlap with the projection area of the extending portion. According to the aspect 5, the extending direction of the groove portion (the liquid spreading direction in the top sheet) and the extending direction of the extending portion of the low-pressure squeezing concave portion (the liquid diffusion direction in the absorber) coincide with each other, and Since the extension part of a recessed part overlaps in the thickness direction of an absorbent article, the liquid transferability from the groove part of a top sheet to the extension part of a low pressing recessed part can be improved.

  In a preferable aspect (Aspect 6) of the absorbent article according to Aspect 5, 5% or more of the projected area of the groove overlaps with the projected area of the extending portion. According to the aspect 6, the liquid transferability from the groove portion of the top sheet to the extended portion of the low-pressure squeezed concave portion can be improved.

  In a preferred aspect (Aspect 7) of the absorbent article according to Aspect 5 or Aspect 6, the overlap between the projection area of the groove and the projection area of the extending portion extends over the entire short direction of the projection area of the groove. Arise. According to the aspect 7, the liquid transferability from the groove portion of the top sheet to the extended portion of the low-pressure squeezed concave portion can be improved. Aspect 7 can be combined with Aspect 5 and / or Aspect 6.

  In a preferable aspect (Aspect 8) of the absorbent article according to any one aspect of Aspects 4 to 7, the flange portion is a central portion located in the center in the short direction, and the short side relative to the central portion. Both side portions located on both sides in the direction, the central portion has a fiber density lower than the average fiber density of the entire collar portion, and the both side portions have an average fiber density of the entire collar portion. Has higher fiber density. According to the aspect 8, since the fiber density of the both side parts of the collar part is higher than the fiber density of the center part of the collar part, the retention of the liquid in the center part of the collar part can be suppressed. The supplied liquid can be efficiently guided to the groove portion of the top sheet. Aspect 8 can be combined with one of Aspects 4 to 7 or two or more aspects that can be arranged side by side.

  In a preferred aspect (Aspect 9) of the absorbent article of the present invention, the absorbent body has a central portion located at the center in the longitudinal direction, and both side portions located on both sides in the longitudinal direction with respect to the central portion. The pressing recess is formed in the both side portions, but is not formed in the central portion. According to the aspect 9, in the central part of the absorbent body in which the compressed concave portion is not formed (therefore, the fiber density is low), the liquid having a relatively high flow rate immediately after being supplied to the top sheet can be absorbed. In the both side portions of the absorbent body in which the compressed concave portions are formed (therefore, the fiber density is high), it is possible to draw into the absorbent body a liquid having a relatively low flow velocity that flows along the top sheet surface. The aspect 9 can be combined with one of the aspects 1 to 8 or two or more aspects that can be arranged side by side.

  In a preferred embodiment (embodiment 10) of the absorbent article of the present invention, the high-pressure depression is formed in an intersecting region of the mesh pattern. According to the tenth aspect, since the high-pressure recessed portion is provided in the intersecting region of the mesh pattern in which force is easily applied when the absorbent article is used, the separation between the absorbent core and the backsheet-side covering sheet can be prevented. As a result, the mesh pattern of the low-pressure depressions can be maintained. The aspect 10 can be combined with one of the aspects 1 to 9 or two or more aspects that can be arranged side by side.

  In a preferred embodiment (embodiment 11) of the absorbent article of the present invention, the topsheet-side covering sheet is bonded to the topsheet-side surface of the absorbent core with an adhesive, and the backsheet-side covering sheet is The absorbent core is bonded to the back sheet side surface with an adhesive. According to the aspect 11, the separation between the absorbent core and the top sheet side covering sheet and the back sheet side covering sheet and the deterioration of the liquid transferability due to the separation can be prevented. In addition, the aspect 11 can be combined with one of the aspects 1 to 10 or two or more aspects that can be arranged side by side.

In a preferred embodiment (embodiment 12) of the absorbent article of the present invention, the top sheet has a kinematic viscosity at 40 ° C. of 0.01 to 80 mm ² / s, a water retention of 0.01 to 4.0 mass%, A blood slipperiness imparting agent having a weight average molecular weight of less than 1,000 is applied. Aspect 12 is particularly useful when the liquid supplied to the top sheet is blood (for example, menstrual blood excreted from the wearer). That is, the blood supplied to the top sheet can slide down to the low fiber density region of the top sheet together with the blood slipperiness imparting agent applied to the top sheet, and can be transferred to the absorber. Therefore, according to the aspect 11, the blood remaining on the top sheet can be reduced, thereby preventing the stickiness of the top sheet and maintaining the smooth feeling. In addition, the aspect 12 can be combined with one aspect or two or more aspects that can be juxtaposed among the aspects 1 to 11.

  In aspect 12, the IOB of the blood slipperiness imparting agent is preferably 0.00 to 0.60.

In aspect 12, the blood slipperiness imparting agent is preferably the following (i) to (iii):
(I) hydrocarbons,
(Ii) from (ii-1) a hydrocarbon moiety and (ii-2) a carbonyl group (—CO—) and an oxy group (—O—) inserted between the C—C single bonds of the hydrocarbon moiety. A compound having one or more of the same or different groups selected from the group consisting of: (iii) (iii-1) a hydrocarbon moiety, and (iii-2) a CC single bond of said hydrocarbon moiety One or more of the same or different groups selected from the group consisting of a carbonyl group (—CO—) and an oxy group (—O—), inserted between them, and (iii-3) of the hydrocarbon moiety A compound having one or a plurality of the same or different groups selected from the group consisting of a carboxyl group (—COOH) and a hydroxyl group (—OH), which replaces a hydrogen atom;
Selected from the group consisting of any combination thereof (in the compound (ii) or (iii), when two or more oxy groups are inserted, each oxy group is not adjacent) ).

In aspect 12, the blood slipperiness imparting agent is preferably the following (i ′) to (iii ′):
(I ′) hydrocarbon,
(Ii ′) (ii′-1) a hydrocarbon moiety and (ii′-2) a carbonyl bond (—CO—), an ester bond (—COO) inserted between the C—C single bonds of the hydrocarbon moiety. -), A carbonate bond (-OCOO-), and a compound selected from the group consisting of an ether bond (-O-) and having one or more same or different bonds, and (iii ') (iii'- 1) a hydrocarbon moiety and (iii′-2) a carbonyl bond (—CO—), an ester bond (—COO—), a carbonate bond (—OCOO) inserted between the C—C single bonds of the hydrocarbon moiety. -), And one or a plurality of the same or different bonds selected from the group consisting of an ether bond (-O-), and (iii'-3) a carboxyl group that replaces a hydrogen atom of the hydrocarbon moiety ( -COOH) and hydroxy A compound having one or a plurality of the same or different groups selected from the group consisting of a sil group (—OH);
As well as any combination thereof (wherein (ii ′) or (iii ′) compounds wherein two or more identical or different bonds are inserted, each bond is adjacent) Not)

In aspect 12, the blood slipperiness imparting agent is preferably the following (A) to (F):
(A) (A1) a compound having a chain hydrocarbon moiety and 2 to 4 hydroxyl groups replacing hydrogen atoms in the chain hydrocarbon moiety, (A2) a chain hydrocarbon moiety, and the chain An ester with a compound having one carboxyl group for substituting a hydrogen atom in the hydrocarbon moiety,
(B) (B1) a compound having a chain hydrocarbon moiety and 2 to 4 hydroxyl groups replacing hydrogen atoms in the chain hydrocarbon moiety, (B2) a chain hydrocarbon moiety, and the chain An ether with a compound having one hydroxyl group replacing a hydrogen atom of the hydrocarbon moiety,
(C) (C1) a carboxylic acid, a hydroxy acid, an alkoxy acid or an oxo acid containing a chain hydrocarbon moiety and 2 to 4 carboxyl groups replacing the hydrogen atom of the chain hydrocarbon moiety; C2) an ester of a chain hydrocarbon moiety and a compound having one hydroxyl group replacing a hydrogen atom of the chain hydrocarbon moiety,
(D) an ether bond (—O—), a carbonyl bond (—CO—), an ester bond (—COO—) inserted between the chain hydrocarbon moiety and the C—C single bond of the chain hydrocarbon moiety. And a compound having any one bond selected from the group consisting of a carbonate bond (—OCOO—),
(E) polyoxy C ₃ -C ₆ alkylene glycol or its alkyl ester or alkyl ether, and (F) a chain hydrocarbon,
As well as any combination thereof.

In aspect 12, the blood slipperiness imparting agent is preferably (a ₁ ) an ester of a chain hydrocarbon tetraol and at least one fatty acid, or (a ₂ ) a chain hydrocarbon triol and at least one fatty acid. An ester, (a ₃ ) an ester of a chain hydrocarbon diol and at least one fatty acid, (b ₁ ) an ether of a chain hydrocarbon tetraol and at least one aliphatic monohydric alcohol, (b ₂ ) a chain carbonization Ether of hydrogen triol and at least one aliphatic monohydric alcohol, (b ₃ ) ether of chain hydrocarbon diol and at least one aliphatic monohydric alcohol, (c ₁ ) chain having four carboxyl groups hydrocarbon tetracarboxylic acid, hydroxy acids, esters of alkoxy acids or oxoacids, and at least one aliphatic monohydric alcohol, (c ₂₎ 3 amino carbonitrile Chain hydrocarbon tricarboxylic acid having a sill group, hydroxy acid, alkoxy acid or oxo acid, at least one ester of an aliphatic monohydric alcohol, (c ₃₎ a chain hydrocarbon dicarboxylic acids having two carboxyl groups , An ester of a hydroxy acid, an alkoxy acid or an oxo acid and at least one aliphatic monohydric alcohol, (d ₁ ) an ether of an aliphatic monohydric alcohol and an aliphatic monohydric alcohol, (d ₂ ) a dialkyl ketone, d ₃ ) an ester of a fatty acid and an aliphatic monohydric alcohol, (d ₄ ) a dialkyl carbonate, (e ₁ ) a polyoxy C ₃ -C ₆ alkylene glycol, (e ₂ ) a polyoxy C ₃ -C ₆ alkylene glycol and at least one esters of fatty acids, (e ₃₎ polyoxy C ₃ -C ₆ alkylene glycol and at least one aliphatic Ataia Ethers of call and, (f ₁₎ a chain alkane, and is selected from the group consisting of any combination thereof.

  The kind and application of the absorbent article of the present invention are not particularly limited. Examples of the absorbent article include sanitary products and sanitary products such as sanitary napkins, disposable diapers, panty liners, incontinence pads, sweat removing sheets, etc., and these may be used for humans and other than humans such as pets. Animals may be targeted. The liquid which the absorbent article is to be absorbed is not particularly limited, and examples thereof include liquid excretion excreted from the wearer (for example, menstrual blood, urine, descending product, etc.).

Hereinafter, an embodiment of the absorbent article of the present invention will be described based on the drawings, taking a sanitary napkin as an example.
As shown in FIGS. 1 to 3, a sanitary napkin 1 according to an embodiment of the present invention includes a liquid-permeable top sheet 2, a liquid-impermeable back sheet 3, a top sheet 2, and a back sheet 3. And an absorber 4 provided between the two.

  As shown in FIGS. 1 to 3, the sanitary napkin 1 has a transverse direction X, a longitudinal direction Y, and a thickness direction Z that are orthogonal to each other. The top sheet 2, the absorber 4 and the back sheet 3 are sequentially laminated in the thickness direction Z, and the thickness direction Z coincides with the lamination direction of the top sheet 2, the absorber 4 and the back sheet 3. Hereinafter, unless otherwise specified, “width” means the dimension in the short direction X, “length” means the dimension in the longitudinal direction Y, and “thickness” means the dimension in the thickness direction Z. means.

  The sanitary napkin 1 has a skin-side surface located on the wearer's skin side and a clothing-side surface located on the wearer's clothing (underwear) side when worn. The skin side surface of the sanitary napkin 1 is constituted by one surface (the upper surface in FIGS. 2 and 3) of the top sheet 2, and the clothing side surface of the sanitary napkin 1 is one surface of the back sheet 3 ( 2 and 3, the lower surface).

  The sanitary napkin 1 is worn for the purpose of absorbing liquid excretion (particularly menstrual blood) excreted from the wearer. At this time, the top sheet 2 is worn on the skin side of the wearer, and the back sheet 3 is worn on the clothes (underwear) side of the wearer. The liquid excretion excreted from the wearer passes through the top sheet 2 to reach the absorber 4 and is absorbed and held by the absorber 4. Leakage of liquid excretion absorbed and held by the absorber 4 is prevented by the back sheet 3.

  As shown in FIG. 1, the top sheet 2 and the back sheet 3 are joined at their longitudinal ends by seal portions 11 a and 11 b to form a main body portion 6, and end portions in the width direction are sealed portions 12 a. , 12b and substantially rectangular wings 7a, 7b extending in the width direction from the main body 6 are formed.

  The shape of the main body 6 can be appropriately changed within a range suitable for a female body, underwear, and the like, and may be, for example, a substantially rectangular shape, a substantially oval shape, a substantially saddle shape, or the like. The length of the main body 6 is usually 100 to 500 mm, preferably 150 to 350 mm, and the width of the main body 6 is usually 30 to 200 mm, preferably 40 to 180 mm.

  Examples of the bonding mode by the seal portions 11a, 11b, 12a, and 12b include bonding by heat embossing, bonding by ultrasonic embossing, and bonding by a hot melt adhesive. In order to increase the bonding strength, two or more bonding modes may be combined (for example, a combination of bonding with a hot-melt adhesive and embossing performed thereafter).

  As shown in FIG. 2, adhesive portions 13 a and 13 b are provided on the clothing side of the backsheet 3 that forms the wing portions 7 a and 7 b, and on the clothing side of the backsheet 3 that forms the main body portion 6, An adhesive portion 13c is provided. The sanitary napkin 1 is obtained by attaching the adhesive part 13c to the crotch part of the underwear, bending the wing parts 7a and 7b to the outer surface side of the underwear, and attaching the adhesive parts 13a and 13b to the crotch part of the underwear. Stablely fixed to underwear.

  Examples of the adhesive contained in the adhesive portions 13a, 13b, and 13c include, for example, styrene-ethylene-butylene-styrene block copolymer, styrene-butylene polymer, styrene-butylene-styrene block copolymer, styrene-isobutylene- Styrene polymers such as styrene copolymers; tackifiers such as C5 petroleum resins, C9 petroleum resins, dicyclopentadiene petroleum resins, rosin petroleum resins, polyterpene resins, terpene phenol resins; trifresyl phosphate, phthalic acid Examples include monomer plasticizers such as dibutyl and dioctyl phthalate; polymer plasticizers such as vinyl polymer and polyester.

  The top sheet 2 is a non-woven fabric through which liquid excretion excreted from the wearer can permeate. The kind of nonwoven fabric used as the top sheet 2, thickness, basic weight, etc. are not specifically limited as long as the liquid excretion excreted from the wearer can permeate.

  Examples of the fibers constituting the nonwoven fabric include natural fibers (for example, wool, cotton, etc.), regenerated fibers (for example, rayon, acetate, etc.), inorganic fibers (for example, glass fibers, carbon fibers, etc.), thermoplastic resin fibers ( For example, polyolefins such as polyethylene, polypropylene, polybutylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-acrylic acid copolymer, ionomer resin; polyethylene terephthalate, polybutylene terephthalate, polytrimethylene And polyesters such as terephthalate and polylactic acid; polyamides such as nylon). The fibers constituting the nonwoven fabric are: core-sheath fibers, side-by-side fibers, island / sea fibers, etc .; hollow fibers; flat fibers, Y-shaped fibers, C-shaped fibers, etc .; latent crimps Alternatively, it may be a three-dimensional crimped fiber of actual crimp; a split fiber that is split by a physical load such as water flow, heat, embossing, or the like.

  Nonwoven fabric production methods include, for example, a method of forming a web (fleece) and physically and chemically bonding fibers. Examples of web formation methods include a spunbond method and a dry method (car Bonding methods, melt blown methods, airlaid methods, etc.), wet methods, and the like. Examples of the bonding method include a thermal bond method, a chemical bond method, a needle punch method, a stitch bond method, and a spunlace method.

  Examples of the nonwoven fabric used as the top sheet 2 include an air-through nonwoven fabric, a spunbond nonwoven fabric, a point bond nonwoven fabric, a spunlace nonwoven fabric, a needle punch nonwoven fabric, a melt blown nonwoven fabric, and a combination thereof (for example, a spunbond / meltblown / spunbond ( SMS) non-woven fabric etc.), etc., among which air-through non-woven fabric is preferred. Since the air-through nonwoven fabric has a relatively low fiber density, the use of the air-through nonwoven fabric as the top sheet 2 can reduce liquid excrement remaining on the top sheet 2. The air-through nonwoven fabric can be produced, for example, by spraying hot air on a web containing thermoplastic resin fibers to thermally bond the thermoplastic resin fibers.

  As shown in FIGS. 1 to 3, the top sheet 2 has a surface region 20 that receives supply of liquid excretion excreted from the wearer. The surface region 20 is located substantially at the center of the absorber arrangement region, and the inner compressed groove 5a is intermittently formed at the periphery of the surface region 20. In addition, an absorber arrangement | positioning area | region is an area | region with which the absorber 4 overlaps with the top sheet 2 when the absorber 4 is projected on the top sheet 2 (refer FIG. 1). The position and size of the surface area 20 can be appropriately adjusted in consideration of the position and size of the excretory opening contact area where the wearer's excretion opening (eg, small labia, large labia, etc.) abuts. The surface area 20 is preferably set as an area larger than the excretion opening contact area including the excretion opening contact area and the surrounding area from the viewpoint of preventing leakage of liquid excretion to the outside. The length of the surface region 20 is usually 50 to 200 mm, preferably 70 to 150 mm, and the width of the surface region 20 is usually 10 to 80 mm, preferably 20 to 50 mm.

  From the viewpoint of improving the concealability of the top sheet 2, the nonwoven fabric used as the top sheet 2 may contain an inorganic filler such as titanium oxide, barium sulfate, or calcium carbonate. When a nonwoven fabric contains a core-sheath-type conjugate fiber, an inorganic filler may be contained only in the core of the core-sheath-type conjugate fiber, or an inorganic filler may be contained only in the sheath of the core-sheath-type conjugate fiber.

  As shown in FIGS. 1 to 4, the top sheet 2 is a nonwoven fabric having a plurality of ridges 21 extending in the longitudinal direction Y and a plurality of grooves 22 extending in the longitudinal direction Y. The top sheet 2 is partitioned into a high fiber density region and a low fiber density region in plan view (see FIG. 1), and the flange portion 21 corresponds to a high fiber density region having a fiber density higher than that of the groove portion 22. Corresponds to a low fiber density region where the fiber density is lower than that of the flange 21. Since the liquid excrement supplied to the top sheet 2 tends to spread in the longitudinal direction Y along the collar part 21 and the groove part 22, the liquid excrement supplied to the top sheet 2 spreads in the short direction X and Leakage from the sanitary napkin 1 can be prevented.

  When the top sheet 2 is projected onto a virtual plane P (see FIGS. 1 to 3) perpendicular to the thickness direction Z, the ratio of the total area of the projection area of the groove 22 to the total area of the projection area of the flange 21 ( The total area of the projection area of the groove 22: the total area of the projection area of the flange 21) is usually 1: 1 to 1:20, preferably 1: 1 to 1:10, more preferably 1: 1 to 1: 8. It is.

  “High fiber density” and “low fiber density” mean the relative high or low fiber density. Since the liquid tends to shift from a portion having a low fiber density to a portion having a high fiber density, the high or low fiber density is a liquid that is colored with respect to the nonwoven fabric used as the top sheet 2 (for example, a liquid containing a pigment). It can be evaluated by the shade of the color after dropping. That is, the dark part can be evaluated as a part with a large liquid migration amount, that is, a part with a relatively high fiber density, and the light color part has a small liquid migration amount, that is, a fiber density. It can be evaluated as a relatively small portion.

  As shown in FIGS. 1 and 2, the plurality of flange portions 21 extending in the longitudinal direction Y are arranged in the short direction X at substantially equal intervals. Similarly, the plurality of flange portions 21 extending in the longitudinal direction Y are also arranged in the short direction X at substantially equal intervals. As shown in FIGS. 1 and 2, the flange portions 21 and the groove portions 22 are alternately disposed in the lateral direction X, and one groove portion 22 is disposed between the two flange portions 21. Such an arrangement pattern of the flange portion 21 (high fiber density region) and the groove portion 22 (low fiber density region) is an example of an arrangement pattern of the high fiber density region and the low fiber density region. The arrangement pattern of the density region is not limited to this embodiment. For example, the high fiber density region and the low fiber density region may extend in the lateral direction X and be aligned in the longitudinal direction Y. The high fiber density region and the low fiber density region may extend intermittently in the longitudinal direction Y. Further, the high fiber density region and the low fiber density region may extend in the longitudinal direction Y while changing the extending direction (for example, wavy lines). Further, two or more low fiber density regions extending in the longitudinal direction Y may be arranged between two high fiber density regions extending in the longitudinal direction Y. A plurality of high fiber density regions or low fiber density regions extending in the longitudinal direction Y may be arranged in the short direction X at different intervals. Further, one of the high fiber density region and the low fiber density region may be scattered and surrounded by the other. Of these changes, two or more types of changes that can be juxtaposed may be combined.

  As shown in FIGS. 2 and 4, the surface of the flange portion 21 is a curved surface, and the cross-sectional shape of the flange portion 21 is a substantially inverted U-shape toward the surface. Such a shape of the collar portion 21 is an example of a shape of the collar portion, and the shape of the collar portion is not limited to the present embodiment. For example, the cross-sectional shape of the collar portion may be trapezoidal, triangular, Ω-shaped square, or the like. However, the cross-sectional shape of the collar portion is preferably a shape whose width decreases from the bottom portion toward the top portion. Thereby, even if force (for example, a wearer's body pressure) is applied to the sanitary napkin 1 and the buttocks are crushed, the space of the groove portion can be maintained.

  As shown in FIG. 4, the flange portion 21 has a thickness T1, and the groove portion 22 has a thickness T2. The thickness T1 of the flange portion 21 is preferably 0.3 to 15 mm, more preferably 0.5 to 5 mm, and the thickness T2 of the groove portion 22 is usually 90% or less, preferably 50% of the thickness T1 of the flange portion 21. Hereinafter, it is more preferably 20% or less. The thickness T2 of the groove portion 22 is usually 1% or more, preferably 5% or more of the thickness T1 of the flange portion 21. The thickness T1 of the flange 21 is measured as a distance from the lower surface of the topsheet 2 to the highest point of the flange 21 based on a cross-sectional photograph or a cross-sectional image of the topsheet 2 in a non-pressurized state. The same applies to the thickness T2 of the groove 22.

  As shown in FIG. 4, the flange portion 21 has a width W1, and the groove portion 22 has a width W2. The width W1 of the flange portion 21 is preferably 0.5 to 30 mm, more preferably 1.0 to 10 mm, and the width W2 of the groove portion 22 is preferably 0.1 to 30 mm, more preferably 0.5 to 10 mm. It is. The interval between the flange portions 21 is usually equal to the width W2 of the groove portion, and the interval between the groove portions 22 is usually equal to the width of the flange portion 21. The width W1 of the flange portion 21 is measured as a distance between the boundary lines with the groove portion 22 located on both sides of the flange portion 21 based on a planar photograph or a plane image of the top sheet 2 in a non-pressurized state. . The width W2 of the groove 22 is the same.

  In the present embodiment, the thickness T1 and the width W1 of the flange 21 are substantially the same in any flange 21, but there may be flanges having different thicknesses and widths. In the present embodiment, the thickness T2 and the width W2 of the groove portion 22 are substantially the same in any groove portion 22, but there may be groove portions having different thicknesses and widths.

  As shown in FIG. 4, the collar portion 21 includes a central portion 211 located in the center in the short direction X and both side portions 212 a and 212 b located on both sides in the short direction X with respect to the central portion 211. The central portion 211 is thicker than the side portions 212a and 212b, and has a fiber density lower than the average fiber density of the entire collar portion 21. In addition, the fiber density of the center part 211 is substantially uniform. Both side portions 212a and 212b are thinner than the central portion 211, and have a fiber density higher than the average fiber density of the entire collar portion 21. In addition, the fiber density of both side parts 212a and 212b is substantially uniform. By making the fiber density of the both side portions 212a and 212b of the collar part 21 higher than the fiber density of the central part 211 of the collar part 21, it is possible to suppress the retention of liquid excrement in the central part 211 of the collar part 21, Thereby, the liquid excretion supplied to the top sheet 2 can be efficiently guided to the groove portion 22 of the top sheet 2.

  The fiber density of the central portion 211 and both side portions 212a and 212b are both higher than the fiber density of the groove portion 22. Therefore, the groove part 22 is a low fiber density area | region where a fiber density is lower than any of the center part 211 and both side part 212a, 212b.

Fiber density of the central portion 211 of the ridge portion 21 is preferably 0.005~0.20g / cm ^3, more preferably a 0.007~0.07g / cm ^3. When the fiber density of the central portion 211 is less than 0.005 g / cm ³ , when force (for example, body pressure of the wearer) is applied to the sanitary napkin 1, the central portion 211 is easily crushed and the absorbent body 4 The absorbed liquid excretion is likely to return backward through the central portion 211. On the other hand, if the fiber density of the central portion 211 is greater than 0.20 g / cm ³ , liquid excreta tends to stay in the central portion 211.

The fiber density of both side portions 212a and 212b of the collar portion 21 is preferably 0.007 to 0.40 g / cm ³ , more preferably 0.01 to 0.20 g / cm ³ . When the fiber density of both side portions 212a and 212b is smaller than 0.007 g / cm ³ , both side portions 212a and 212b are easily stretched by line tension. On the other hand, when the fiber density of both side portions 212a and 212b is larger than 0.40 g / cm ³ , liquid excrement tends to stay in both side portions 212a and 212b.

The average fiber density of the entire collar portion 21 (central portion 211 and both side portions 212a and 212b) is preferably 0.005 to 0.2 g / cm ³ , more preferably 0.007 to 0.07 g / cm ³ .

Fiber density of the groove 22 is preferably 0.002~0.18g / cm ^3, more preferably a 0.005~0.05g / cm ^3. When the fiber density of the groove part 22 is smaller than 0.002 g / cm ³ , the groove part 22 of the top sheet 2 is easily damaged when the sanitary napkin 1 is used. On the other hand, when the fiber density of the groove part 22 is larger than 0.18 g / cm < ³ >, liquid excretion will stay in the groove part 22 easily.

The average basis weight of the whole nonwoven fabric used as the top sheet 2 is preferably 10 to 200 g / m ² , more preferably 20 to 100 g / m ² . If the average basis weight is less than 10 g / m ² , the top sheet 2 may be damaged when the sanitary napkin 1 is used. On the other hand, the average basis weight of greater than 200 g / m ^2, the liquid excrement tends to stay in the top sheet 2.

In the present embodiment, the basis weight of the groove portion 22 is adjusted to be smaller than the basis weight of the flange portion 21 and smaller than the average basis weight of the entire nonwoven fabric. Specifically, the basis weight of the groove 22 is preferably 3 to 150 g / m ² , and more preferably 5 to 80 g / m ² . If the basis weight of the groove 22 is less than 3 g / m ² , the top sheet 2 may be damaged when the sanitary napkin 1 is used. On the other hand, when the basis weight of the groove part 22 is larger than 150 g / m ² , liquid excrement tends to stay in the groove part 22.

The collar portion 21 is adjusted so that the average basis weight is higher than that of the groove portion 22. The basic weight of the central part 211 of the collar part 21 is 15-250 g / m < ² > normally, Preferably it is 20-120 g / m < ² >. When the basis weight of the central portion 211 is smaller than 15 g / m ² , the central portion 211 is liable to be crushed and the liquid excretion absorbed by the absorbent body 4 is easily returned under pressure. On the other hand, if the basis weight of the central portion 211 is larger than 250 g / m ² , liquid excreta tends to stay in the central portion 211.

The basis weight of both side portions 212a and 212b of the flange portion 21 is preferably 20 to 280 g / m ² , more preferably 25 to 150 g / m ² . If the basis weight of both side portions 212a and 212b is smaller than 20 g / m ² , both side portions 212a and 212b are easily stretched by line tension. On the other hand, if the basis weights of both side portions 212a and 212b are larger than 280 g / m ² , the transferability of liquid excreta is lowered and the liquid excrement tends to stay in both side portions 212a and 212b.

  The average basis weight of the groove part 22 is adjusted to be lower than the average basis weight of the entire flange part 21. Specifically, the average basis weight of the groove part 22 is usually 90% or less, preferably 3 to 90%, more preferably 3 to 70% of the average basis weight of the entire flange part 21. If the average basis weight of the groove part 22 is larger than 90% of the average basis weight of the entire collar part 21, liquid excrement tends to stay in the groove part 22, and liquid excrement may overflow from the groove part 22. On the other hand, if the average basis weight of the entire groove portion 22 is smaller than 3% of the average basis weight of the entire collar portion 21, the top sheet 2 may be damaged when the sanitary napkin 1 is used.

  The nonwoven fabric used as the top sheet 2 preferably contains thermoplastic resin fibers. When a nonwoven fabric contains a thermoplastic resin fiber, the morphology of the collar part 21 and the groove part 22 can be maintained by heat-seal | fusing a thermoplastic resin fiber. Examples of the thermoplastic resin constituting the thermoplastic resin fiber include polyolefin, polyester, polyamide, and the like. Examples of the polyolefin include, for example, linear low density polyethylene (LLDPE), low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), polypropylene, polybutylene, and copolymers based on these (for example, Ethylene-vinyl acetate copolymer (EVA), ethylene-ethyl acrylate copolymer (EEA), ethylene-acrylic acid copolymer (EAA), ionomer resin), and the like. Examples of the polyester include linear or branched carbon atoms of up to 20 including polyethylene terephthalate (PET), polytrimethyl terephthalate (PTT), polybutylene terephthalate (PBT), polylactic acid, and polyglycolic acid. And polyesters such as polyhydroxyalkanoic acid, copolymers based on these, and copolymerized polyesters obtained by copolymerizing alkylene terephthalate as a main component with a small amount of other components. Examples of the polyamide include 6-nylon and 6,6-nylon. The fineness of the thermoplastic resin fiber is usually 1.1 to 8.8 dtex, preferably 2.2 to 5.6 dtex, and the fiber length is usually 20 to 100 mm, preferably 35 to 65 mm. The thermoplastic resin fiber may be hydrophilized. Examples of the hydrophilic treatment of thermoplastic resin fibers include, for example, treatment using a surfactant, a hydrophilic agent, etc. (for example, kneading of a surfactant inside the fiber, application of a surfactant to the fiber surface, etc.), etc. Is mentioned.

  As a method of forming the flange portion 21 and the groove portion 22 in the nonwoven fabric, for example, methods described in JP2008-25079A and JP2008-23326A can be used. In this method, a nonwoven fabric is formed by placing a fiber web on a breathable support member (for example, a net-like support member) and continuously blowing gas onto the upper surface of the fiber web while moving the breathable support member in a predetermined direction. The flange portion 21 and the groove portion 22 are formed in the bottom. In addition, the groove part 22 extended in the moving direction of a breathable support member is formed in the area | region where gas was sprayed, and it forms in the collar part 21 between the two adjacent groove parts 22. FIG. Since the fibers in the region where the gas is blown move to both sides of the groove portion 22, the fiber density of both side portions 212a and 212b of the flange portion 21 is increased. The fiber density of the flange portion 21 and the groove portion 22 can be adjusted to a desired range by adjusting conditions such as the amount of gas blown and the tension of the fiber web.

The thickness and density of the nonwoven fabric can be measured as follows. The thickness of the nonwoven fabric having a size of 100 mm × 100 mm is measured under no load, and the average value of the measured values for the ten nonwoven fabrics is defined as the thickness t ₀ (cm) of the nonwoven fabric. A mass w ₀ (g / cm ² ) per unit area is obtained from the mass of 10 nonwoven fabrics having a size of 100 mm × 100 mm, and the value of w ₀ / t ₀ is defined as a density under no load.

  The sanitary napkin 1 may include a liquid permeable sheet other than the top sheet 2. Examples of the liquid permeable sheet other than the top sheet 2 include a second sheet disposed between the top sheet 2 and the absorber 4. Examples of the liquid permeable sheet used as the second sheet include a nonwoven fabric, a woven fabric, and a synthetic resin film in which liquid permeable holes are formed. Among these, a nonwoven fabric is preferable. The specific example of the fiber which comprises a nonwoven fabric, and the specific example of the manufacturing method of a nonwoven fabric are the same as the specific example described regarding the top sheet 2. FIG.

  The back sheet 3 is a liquid impervious sheet through which liquid excretion excreted from the wearer cannot permeate. The backsheet 3 preferably has moisture permeability in addition to liquid impermeability in order to reduce stuffiness when worn. The type, thickness, basis weight, etc. of the liquid impermeable sheet used as the back sheet 3 are not particularly limited as long as the liquid excretion excreted from the wearer cannot permeate. Examples of the liquid-impermeable sheet used as the back sheet 3 include a waterproof nonwoven fabric, a synthetic resin (for example, polyethylene, polypropylene, polyethylene terephthalate, etc.) film, a composite sheet of a nonwoven fabric and a synthetic resin film (for example, a span). Composite film in which a breathable synthetic resin film is bonded to a nonwoven fabric such as bond or spunlace), an SMS nonwoven fabric in which a melt-blown nonwoven fabric having high water resistance is sandwiched between strong spunbond nonwoven fabrics, and the like.

  As shown in FIGS. 2 and 3, the absorbent body 4 includes an absorbent core 41, a topsheet-side covering sheet 42 that covers the surface of the absorbent core 41 on the topsheet 2 side, and a backsheet side of the absorbent core 41. It has the back sheet side coating sheet 43 which coat | covers the surface, and the pressing recessed part 45 formed by pressing the back sheet side coating sheet 43 in the direction of the absorptive core 41. FIG.

The top sheet side covering sheet 42 is bonded to the top sheet side surface of the absorbent core 41 with an adhesive (for example, hot melt adhesive), and the back sheet side covering sheet 43 is the back sheet side of the absorbent core 41. It is preferable to be bonded to the surface by an adhesive (for example, a hot melt adhesive). Thereby, the separation | separation with the absorptive core 41, the top sheet | seat side coating sheet 42, and the back sheet | seat side coating sheet 43 and the fall of the transferability of the liquid excretion resulting therefrom can be prevented. From the viewpoint of liquid permeability, the adhesive is not applied to the entire interface between the top sheet side covering sheet 42 and the absorbent core 41 and the entire interface between the back sheet side covering sheet 43 and the absorbent core 41. It is preferable that the coating is performed in a pattern such as a dot, a spiral, or a stripe. As the adhesive, for example, styrene-ethylene-butadiene-styrene (SEBS), styrene-butadiene-styrene (SBS), styrene-isoprene-styrene (SIS) or the like mainly composed of rubber or linear low density Pressure-sensitive adhesive or heat-sensitive adhesive mainly composed of olefin such as polyethylene; water-soluble polymer (for example, polyvinyl alcohol, carboxymethyl cellulose, gelatin, etc.) or water-swellable polymer (for example, polyvinyl acetate, polyacrylic acid) And water-sensitive adhesives such as sodium). Examples of the method for applying the adhesive include spiral coating, coater coating, curtain coater coating, and summit gun coating. The coating amount of the adhesive (basis weight) is usually 0.1 to 200 g / m ^2, preferably from 1 to 100 g / m ^2.

  In the present embodiment, the length and width of the covering sheets 42 and 43 are larger than the length and width of the absorbent core 41, and the portion of the covering sheets 42 and 43 that extends from the absorbent core 41 is the covering sheet 42. , 43 are bonded by an adhesive applied to at least one of them (for example, a hot melt adhesive). Therefore, in the present embodiment, the entire absorbent core 41 is covered with the covering sheets 42 and 43. By covering the absorbent core 41 with the covering sheets 42 and 43, preventing the collapse of the absorbent core 41, improving the cushioning property of the absorbent body 4, improving the concealing property of the absorbent body 4, reducing the rewetting back of the absorbent body 4, Improvement of the shape maintaining property of the through hole 5 can be realized. However, such a covering form by the covering sheets 42 and 43 is an example of a covering form of the absorbent core by the top sheet side covering sheet and the back sheet side covering sheet, and by the top sheet side covering sheet and the back sheet side covering sheet. The covering form of the absorbent core is not limited to this embodiment. For example, the length and width of the topsheet-side covering sheet may be substantially the same as or less than the length and width of the topsheet-side surface of the absorbent core. Further, the length and width of the backsheet-side cover sheet may be substantially the same as or less than the length and width of the backsheet-side surface of the absorbent core.

  The absorptive core 41 contains the absorptive fiber which can absorb and hold | maintain the liquid excretion excreted from a wearer. The kind of the absorbent fiber contained in the absorbent core 41 is not particularly limited as long as the liquid excretion excreted from the wearer can be absorbed and retained. The absorbent core 41 may contain a superabsorbent material (for example, a superabsorbent resin, a superabsorbent fiber, etc.) in addition to the absorbent fiber. The absorbent core 41 is made of an antioxidant, a light stabilizer, an ultraviolet absorber, a neutralizer, a nucleating agent, an epoxy stabilizer, a lubricant, an antibacterial agent, a flame retardant, an antistatic agent, a pigment, a plasticizer, and the like. You may contain an additive as needed.

  Examples of the absorptive fibers include cellulosic fibers, and examples of the cellulosic fibers include wood pulp obtained from softwood or hardwood as a raw material (for example, groundwood pulp, refiner ground pulp, thermomechanical pulp, chemithermomechanical). Machine pulp such as pulp; chemical pulp such as kraft pulp, sulfide pulp and alkali pulp; semi-chemical pulp etc.); mercerized pulp or crosslinked pulp obtained by chemically treating wood pulp; bagasse, kenaf, bamboo, hemp, Non-wood pulp such as cotton (for example, cotton linter); regenerated cellulose such as rayon and fibril rayon; semi-synthetic cellulose such as acetate and triacetate.

  Examples of the superabsorbent material include starch, cellulose, and synthetic polymer superabsorbent materials. Examples of the starch-based or cellulose-based superabsorbent material include starch-acrylic acid (salt) graft copolymers, saponified starch-acrylonitrile copolymers, and crosslinked products of sodium carboxymethyl cellulose, and synthetic polymers. Examples of high-absorbency materials include polyacrylates, polysulfonates, maleic anhydrides, polyacrylamides, polyvinyl alcohols, polyethylene oxides, polyaspartates, polyglutamates , Polyalginate-based, starch-based, cellulose-based superabsorbent resins (Superabsorbent Polymer: SAP), etc., among which polyacrylate-based (especially sodium polyacrylate-based) superabsorbent Resins are preferred. Examples of the shape of the superabsorbent material include a particulate shape, a fibrous shape, and a scaly shape. When the shape is particulate, the particle size is preferably 50 to 1000 μm, and more preferably 100 to 600 μm. .

  When the absorbent core 41 contains a superabsorbent material (for example, a superabsorbent resin, a superabsorbent fiber, etc.), the content of the superabsorbent material is usually 5 to 80% by mass of the absorbent core 41, preferably Is 10 to 60% by mass, more preferably 20 to 40% by mass.

The thickness, basis weight, and the like of the absorbent core 41 can be appropriately adjusted according to characteristics (for example, absorbency, strength, lightness, etc.) that the sanitary napkin 1 should have. The thickness of the absorptive core 41 is 0.1-20 mm normally, Preferably it is 1-15 mm, and basic weight is 30-1500 g / m < ² > normally, Preferably it is 50-1000 g / m < ² >.

  The top sheet side covering sheet 42 and the back sheet side covering sheet 43 are liquid permeable sheets through which liquid excretion excreted from the wearer can permeate. The kind, thickness, basis weight, etc. of the liquid permeable sheet used as the top sheet side covering sheet 42 and the back sheet side covering sheet 43 are not particularly limited as long as the liquid excretion excreted from the wearer can permeate. Examples of the liquid permeable sheet used as the top sheet side covering sheet 42 and the back sheet side covering sheet 43 include a nonwoven fabric, a woven fabric, and a synthetic resin film in which liquid permeable holes are formed. Nonwoven fabric is preferred. The specific example of the fiber which comprises a nonwoven fabric, and the specific example of the manufacturing method of a nonwoven fabric are the same as the specific example described regarding the top sheet 2. FIG.

  As a nonwoven fabric used as the top sheet side coating sheet 42 and the back sheet side coating sheet 43, for example, an air-through nonwoven fabric, a spunbond nonwoven fabric, a point bond nonwoven fabric, a spunlace nonwoven fabric, a needle punch nonwoven fabric, a melt blown nonwoven fabric, and a combination thereof ( For example, spunbond, meltblown, spunbond (SMS) non-woven fabric, etc.) are mentioned. Of these, the non-woven fabric used as the topsheet-side covering sheet 42 is preferably an air-through non-woven fabric, and the backsheet-side covering sheet The nonwoven fabric used as 43 is preferably an SMS nonwoven fabric or an airlaid nonwoven fabric. Since the air-through nonwoven fabric has a relatively large interfiber distance, the use of the air-through nonwoven fabric as the top sheet-side covering sheet 42 can suppress the retention of liquid excrement in the top sheet-side covering sheet 42, thereby The transferability of liquid excretion from the sheet-side covering sheet 42 to the absorbent core 41 can be improved. On the other hand, since the SMS nonwoven fabric has high rigidity, by using the SMS nonwoven fabric as the backsheet-side covering sheet 43, deformation that may occur during use of the sanitary napkin 1 can be suppressed. Further, by using an airlaid nonwoven fabric as the backsheet-side covering sheet 43, the liquid excrement transferred from the absorbent core 41 to the backsheet-side covering sheet 43 can diffuse in the surface direction of the backsheet-side covering sheet 43. Thereby, the absorptivity and the retainability of the liquid excrement of the absorber 4 can be improved. When the backsheet-side covering sheet 43 is an airlaid nonwoven fabric containing hydrophilic fibers, such an effect becomes more remarkable. The air-through nonwoven fabric can be produced, for example, by spraying hot air on a web containing thermoplastic resin fibers to heat-seal the thermoplastic resin fibers, and the air-laid nonwoven fabric can be produced, for example, from a web containing hydrophilic fibers. After forming by the airlaid method, it can be produced by bonding the fibers constituting the web with a binder. Specific examples of the hydrophilic fiber are the same as the specific examples of the absorbent fiber described for the absorbent core 41.

  The nonwoven fabric used as the top sheet side covering sheet 42 and the back sheet side covering sheet 43 is preferably a nonwoven fabric containing thermoplastic resin fibers. Thereby, the intensity | strength of the nonwoven fabric used as the top sheet side coating sheet 42 and the back sheet side coating sheet 43 can be increased. The thermoplastic resin fiber may be hydrophilized. Specific examples of the thermoplastic resin fibers and specific examples of the hydrophilic treatment of the thermoplastic resin fibers are the same as the specific examples described for the top sheet 2.

  As shown in FIG. 3, the pressing recess 45 formed by pressing the backsheet-side covering sheet 43 in the direction of the absorbent core 41 has a concave surface toward the topsheet 2. A space is formed between the compressed recess 45 and the backsheet 3.

  As shown in FIG. 5, the absorber 4 has a central portion 40a located in the center in the longitudinal direction Y, and both side portions 40b and 40c located on both sides in the longitudinal direction Y with respect to the central portion 40a. The pressing recess 45 is formed in the both side portions 40b and 40c, but is not formed in the central portion 40a. In the central portion 40a of the absorbent body 4 in which the compressed recess 45 is not formed (and therefore the fiber density is low), liquid excrement having a relatively high flow rate immediately after being supplied to the top sheet 2 can be absorbed. In the both side portions 40a and 40b of the absorbent body 4 in which the compressed recesses 45 are formed (therefore, the fiber density is high), the liquid excrement having a relatively low flow velocity flowing through the surface of the top sheet 2 is absorbed by the absorbent body 4. Can be pulled into.

As shown in FIGS. 3 and 5, the pressing recess 45 includes a high-pressure pressing recess 451 and a low-pressure pressing recess 452. “High-pressure expression” and “low-pressure expression” mean the relative height of the expression, and as shown in FIG. 3, the thickness of the high-pressure depression 451 formed by high-pressure expression is compared with the thickness of the low-pressure depression 452. Thus, the thickness of the low-pressure depression 452 formed by low-pressure squeezing is relatively larger than the thickness of the high-pressure depression 451. The thickness of the high pressure recessed portion 451 is preferably 0.05 to 0.3 mm, more preferably 0.05 to 0.2 mm, and the thickness of the low pressure recessed portion 452 is preferably 0.3 to 0.8 mm, and further Preferably it is 0.3-0.7 mm. The fiber density of the high-pressure squeezed recess 451 formed by high-pressure squeezing is relatively large compared to the fiber density of the low-pressure squeezed concave 452, and the fiber density of the low-pressure squeezed concave 452 formed by low-pressure squeezing is The fiber density is relatively large. The fiber density of the high-pressure depression 451 is preferably 0.15 to 0.30 g / cm ³ , more preferably 0.15 to 0.25 g / cm ³ , and the fiber density of the low-pressure depression 452 is preferably 0. 0.06 to 0.2 g / cm ³ , more preferably 0.08 to 0.15 g / cm ³ . In addition, since the thickness of the low pressing recessed part 452 is smaller than the thickness of the area | region 46 enclosed by the high pressing recessed part 451 and the low pressing recessed part 452, the fiber density of the low pressing recessed part 452 is larger than the fiber density of the area | region 46, and a low pressing recessed part The stiffness of 452 is higher than the stiffness of region 46.

  The fiber density of the low-pressure depression 452 is preferably greater than the fiber density of the groove 22. Thereby, the transferability of the liquid excretion from the groove part 22 to the low pressing recessed part 452 can be improved using the characteristic of the liquid that it is easy to transfer to a part with a high fiber density from a part with a low fiber density.

  It is preferable that the fiber density of the high pressure recessed part 451 is larger than the fiber density of the collar part 21. Thereby, the liquid excretion remaining in the flange portion 21 and the groove portion 22 of the top sheet 2 is drawn into the high-pressure squeezed recess portion 451 by utilizing the characteristic of the liquid that it is easy to shift from the low fiber density portion to the high fiber density portion. be able to.

  As shown in FIGS. 5 and 6, when the absorbent body 4 is viewed in plan from the back sheet side covering sheet 43 side, the low pressing recesses 452 are formed in a mesh pattern, and the high pressing recesses 451 are mesh-like. It is formed so as to be scattered in the pattern.

  In this embodiment, as shown in FIG.5 and FIG.6, the high pressing recessed part 451 is formed in the cross | intersection area | region of a mesh pattern. In other words, the high pressing recesses 451 are scattered in the short direction X and the long direction Y, and the low pressing recesses 452 are formed so as to connect the high pressing recesses 451 in the short direction X and the long direction Y. Has been. By providing the high pressure depression 451 in the crossing region of the mesh pattern where force is easily applied when using the sanitary napkin 1, it is possible to prevent the absorbent core 41 and the backsheet side covering sheet 43 from being separated. The mesh pattern of the low pressure depression 452 can be maintained.

  In this embodiment, as shown in FIGS. 5 and 6, the shape of each mesh in the mesh pattern of the low-pressure depression 452 is a regular hexagon, and the high-pressure depression 451 is arranged at the apex of the regular hexagon, The low pressure recessed part 452 is arrange | positioned at the side of a regular hexagon. Moreover, in this embodiment, as shown in FIG. 6, one high pressing recessed part 451 is comprised by four component 451a, 451b, 451c, 451d which adjoins mutually, and component 451a, 451b, 451c, 451d are each formed in a rectangular shape in plan view. Moreover, in this embodiment, as shown in FIG.5 and FIG.6, since the low pressing recessed part 452 is arrange | positioned at the edge | side of a regular hexagon, regarding one high pressing recessed part 451, three extending from the high pressing recessed part 451 are provided. The low pressure depression 452 (the low pressure depression 452 extending from the high pressure depression 451 downward, upper left and right upward, respectively, a first low pressure depression 452p, a second low pressure depression 452q, and a third low pressure depression 452r, respectively. The angle θ1 formed by the first low pressure depression 452p and the second low pressure depression 452q, the angle θ2 formed by the first low pressure depression 452p and the third low pressure depression 452r, and the second The angle θ3 formed by the low-pressure depression 452q and the third low-pressure depression 452r is 120 degrees. That is, in this embodiment, in the three low-pressure depressions 452 extending from one high-pressure depression 451, the first direction in which one arbitrarily selected low-pressure depression 452 extends and the remaining low-pressure depressions 452 are arbitrarily selected. The plurality of low-pressure squeezing recesses 452 are arranged so that the second direction in which the single low-squeezing recess 452 extends is not 180 degrees (so as not to be linear). Such an arrangement pattern of the high pressing depression 451 and the low pressing depression 452 is an example of an arrangement pattern of the high pressing depression and the low pressing depression, and the arrangement pattern of the high pressing depression and the low pressing depression is limited to the present embodiment. It is not something.

  The pressing recess 45 is formed by heat embossing the absorber 4 from the cover sheet 43 side. In the heat embossing process, a predetermined portion of the surface of the backsheet-side covering sheet 43 is compressed in the direction of the absorbent core 41 until reaching the topsheet-side covering sheet 42 and heated, whereby the backsheet-side covering sheet 43 is heated. A high-pressure recessed portion 451 for integrating the absorbent core 41 and the top sheet-side covering sheet 42 is formed. In the heat embossing process, the predetermined portion of the surface of the backsheet side covering sheet 43 is compressed in the direction of the absorbent core 41 until reaching the absorbent core 41 and heated, whereby the backsheet side covering sheet 43 and the absorption are obtained. A low-pressure squeezed recess 452 is formed to integrate the sex core 41. The heat embossing treatment is performed, for example, between an embossing roll having convex portions provided on the outer peripheral surface and a flat roll having a smooth outer peripheral surface, the back sheet side covering sheet 43, the absorbent core 41, and the top sheet side covering sheet. It is carried out by passing the laminated body in which 42 is sequentially laminated and embossing from the back sheet side covering sheet 43 side. Under the present circumstances, the heating at the time of compression is possible by heating of an embossing roll and / or a flat roll. The convex portions of the embossing roll are provided so as to correspond to the shapes, arrangement patterns, and the like of the high-pressure dents 451 and the low-pressure dents 452. A method for forming the pressing recess 45 including the high-pressure pressing recess 451 and the low-pressure pressing recess 452 is described in detail in Japanese Patent Application Laid-Open No. 2013-78366.

  Since the high pressure recessed portion 451 is formed by integrating the back sheet side covering sheet 43, the absorbent core 41 and the top sheet side covering sheet 42, it appears on the top sheet side surface of the top sheet side covering sheet 42. On the other hand, the low-pressure recessed portion 452 does not appear on the top sheet side surface of the top sheet side covering sheet 42 because the back sheet side covering sheet 43 and the absorbent core 41 are integrated. In the present embodiment, the high-pressure recessed portion 451 integrates the backsheet-side covering sheet 43, the absorbent core 41 and the topsheet-side covering sheet 42, but the backsheet-side covering sheet 43 and the absorbent core 41 are integrated. It may be converted.

  In the heat embossing process, the backsheet side covering sheet 43 and / or the absorbent core 41 is effectively integrated by integrating the backsheet side covering sheet 43 and the absorbent core 41 by thermal fusion of thermoplastic resin fibers. It is preferable to contain a thermoplastic resin fiber. In the heat embossing treatment, the back sheet side covering sheet 43, the absorbent core 41, and the top sheet side covering sheet 42 are effectively integrated by thermal fusion of thermoplastic resin fibers. It is preferable that one or two or more of the absorbent core 41 and the topsheet-side covering sheet 42 contain thermoplastic resin fibers. The thermoplastic resin fiber may be hydrophilized. Specific examples of the thermoplastic resin fibers and specific examples of the hydrophilic treatment of the thermoplastic resin fibers are the same as the specific examples described for the top sheet 2.

  As shown in FIGS. 1 to 3, the sanitary napkin 1 has an inner pressing groove 5 a and an outer pressing groove 5 b formed by pressing the top sheet 2 toward the absorbent body 4. As shown in FIG. 1, the inner side pressing groove 5a is intermittently formed in the periphery of the surface area | region 20 of the top sheet 2, and the outer side pressing groove 5b is formed in the outer side of the inner side pressing groove 5b. Yes. In addition, such a pressing groove is not essential for the sanitary napkin 1, and the presence / absence of the inner pressing groove and the outer pressing groove, the formation pattern, and the like can be changed as appropriate.

  The inner pressing groove 5a and the outer pressing groove 5b are recesses formed by heat embossing. In the heat embossing process, a predetermined part of the skin side surface of the top sheet 2 is compressed and heated in the direction of the absorbent body 4 until it reaches the absorbent core 41. Thereby, the inner side pressing groove 5a and the outer side pressing groove 5b which integrate the top sheet 2, the top sheet side coating sheet 42, and the absorptive core 41 are formed as a recessed part.

  In the heat embossing process, for example, the top sheet 2 and the absorbent body 4 are passed between an embossing roll having convex portions provided on the outer peripheral surface and a flat roll having a smooth outer peripheral surface, and from the top sheet 2 side. Implemented by embossing. Under the present circumstances, the heating at the time of compression is possible by heating of an embossing roll and / or a flat roll. The convex part of the embossing roll is provided so as to correspond to the shape, arrangement pattern, and the like of the inner pressing groove 5a and the outer pressing groove 5b. The heating temperature is usually 80 to 180 ° C., preferably 120 to 160 ° C., the pressure is 10 to 3000 N / mm, preferably 50 to 500 N / mm, and the treatment time is usually 0.0001 to 5 seconds, preferably 0. 0.005 to 2 seconds.

  In the heat embossing treatment, the top sheet 2, the top sheet side covering sheet 42, and the absorbent core 41 are effectively integrated by thermal fusion of thermoplastic resin fibers. And it is preferable that 1 or 2 or more of the absorptive core 41 contains a thermoplastic resin fiber.

  FIG. 7 shows a projection region of the groove portion 22 that is generated when the groove portion 22 of the top sheet 2 and the low pressure recessed portion 452 of the absorber 4 are projected onto a virtual plane P (see FIGS. 1 to 3) perpendicular to the thickness direction Z. It is a partial enlarged view of the virtual plane P which shows the overlap with the projection area | region of the low pressing recessed part 452. In FIG. 7, the projection region R1 of the groove 22 is shown on the back side of the drawing, and the projection region R2 of the low-pressure depression 452 is shown on the front side of the drawing.

  As shown in FIG. 7, when the groove 22 and the low-pressure depression 452 are projected onto the virtual plane P, the projection region R1 of the groove 22 has an overlap L with the projection region R2 of the low-pressure depression 452. That is, the groove part 22 and the low pressure recessed part 452 are arrange | positioned so that it may overlap in the thickness direction Z. Thereby, when the liquid excrement supplied to the top sheet 2 moves to the absorbent body 4 through the groove portion 22 of the top sheet 2, the liquid excrement easily moves to the low-pressure squeezed recess 452 of the absorbent body 4. The ratio of the portion overlapping the projection region R2 of the low-pressure depression 452 in the projection region R1 of the groove 22 is preferably 2% or more, more preferably 5% or more, and even more preferably 7% or more. Thereby, the transferability of the liquid excretion from the groove part 22 of the top sheet 2 to the low pressing recessed part 452 of the absorber 4 can be improved. The ratio of the portion overlapping the projection region R2 of the low-pressure depression 452 in the projection region R1 of the groove 22 is usually 50% or less, preferably 30% or less. In addition, since the high pressing recessed part 451 is scattered in the mesh pattern of the low pressing recessed part 452, the projection area | region of the high pressing recessed part 451 is included in the projection area | region R1 of the low pressing recessed part 452.

  In the present embodiment, as shown in FIG. 7, the low-pressure recessed portion 452 has an extending portion (for example, the first low-pressure recessed portion 452 p) extending in the longitudinal direction Y, and the projection region R <b> 1 of the groove portion 22. However, it has the overlap L with the projection area | region R21 of the extension part of the low pressing recessed part 452. Thereby, while the extension direction of the groove part 22 (the spread direction of the liquid excrement in the top sheet 2) and the extension direction of the extension part of the low pressure depression 452 (the diffusion direction of the liquid excrement in the absorber 4) coincide. In addition, since the extending portions of the groove portion 22 and the low pressure recessed portion 452 overlap in the thickness direction Z of the sanitary napkin 1, the transferability of liquid excretion from the groove portion 22 of the top sheet 2 to the extended portion of the low pressure recessed portion 452 is improved. Can be made. Of the projection region R1 of the groove part 22, the proportion of the portion of the extended portion of the low-pressure depression 452 that overlaps with the projection region R21 is preferably 5% or more, more preferably 7% or more, and even more preferably 10% or more. . Thereby, the transferability of the liquid excretion from the groove part 22 of the top sheet 2 to the extension part of the low pressing recessed part 452 can be improved. In addition, the ratio of the part which overlaps with projection area | region R21 of the extension part of the low pressing recessed part 452 among projection area | region R1 of the groove part 22 is 50% or less normally, Preferably it is 30% or less.

  In the present embodiment, as shown in FIG. 7, the overlap L between the projection region R1 of the groove 22 and the projection region R21 of the extended portion of the low-pressure depression 452 extends over the entire short direction X of the projection region R1 of the groove 22. Arise. Thereby, the transferability of the liquid excretion from the groove part 22 of the top sheet 2 to the extension part of the low pressing recessed part 452 can be improved. Thus, in order for the projection region R1 of the groove portion 22 to be overlapped with the projection region R21 of the extended portion of the low-pressure recessed portion 452 in the state of being included in the projection region R21 of the extended portion of the low-pressure recessed portion 452, at least It is necessary that the width of the groove portion 22 is equal to or less than the width of the low-pressure recessed portion 452.

  In the present embodiment, as shown in FIG. 7, the overlap L between the projection region R1 of the groove 22 and the projection region R2 of the low-pressure squeezed recess 452 is the projection of the extended portion of the projection region R1 of the groove 22 and the low-squeeze recess 452. This coincides with the overlap L with the region R21. However, in the present embodiment, the projection area of the groove portion has an overlap with the projection area of the portion other than the extension portion of the low-pressure depression in addition to the overlap with the projection area of the extension portion of the low-pressure depression. May be changed. Such a change can be realized by changing the number of grooves and / or the interval. For example, in FIG. 7, by adding a new groove projection area between the two groove projection areas, the groove projection area overlaps with the projection area of the extension portion of the low-pressure depression, It will have an overlap with the projection area | region of parts other than an extension part among low pressing recessed parts. In addition, in FIG. 7, by slightly moving the projection region of a certain groove portion in the short direction X (left or right in FIG. 7), the projection region of the groove portion is the same as the projection region of the extension portion of the low-pressure depression. In addition to the overlap, there will be an overlap with the projection region of the portion other than the extended portion of the low-pressure recessed portion. Two or more kinds of these changes may be combined.

  The top sheet 2 is a non-woven fabric having a ridge portion 21 corresponding to a high fiber density region and a groove portion 22 corresponding to a low fiber density region, and the absorbent body 4 includes an absorbent core 41 containing absorbent fibers and an absorbent. The top sheet side covering sheet 42 that covers the top sheet side surface of the absorbent core 41, the back sheet side covering sheet 43 that covers the back sheet side surface of the absorbent core 41, and the back sheet side covering sheet 43 Squeezing recesses 45 formed by squeezing in the direction of squeezing, and the pressing recesses 45 are formed so as to be scattered in the squeezed recesses 452 formed in a mesh pattern and in the mesh pattern. When the groove portion 22 and the low pressure recessed portion 452 are projected onto a virtual plane P perpendicular to the thickness direction Z, the projection area of the groove portion 22 is a low pressure recessed portion. By having an overlap with the 452 projection area of the sanitary napkin 1 can exhibit the following advantages. The groove 22 (low fiber density region) of the top sheet 2 is less liable to retain liquid excrement than the collar portion 21 (high fiber density region), so the liquid excrement supplied to the top sheet 2 It is easy to move to the absorber 4 through the groove 22. The groove portion 22 of the top sheet 2 and the low pressure depression 452 of the absorbent body 4 are arranged such that the projection region R1 of the groove portion 22 has an overlap L with the projection region R2 of the low pressure depression 452 (that is, the thickness of the sanitary napkin 1 Since the liquid excrement supplied to the top sheet 2 moves to the absorbent body 4 through the groove portion 22 of the top sheet, the liquid excrement is compressed into the depression 4 of the absorbent body 4. It is easy to move to 452. Since the low pressure depression 452 of the absorbent body 4 is formed in a mesh pattern, the liquid excretion transferred to the low pressure depression 452 of the absorbent body 4 may diffuse throughout the absorbent body 4 along the mesh pattern. it can. Therefore, the sanitary napkin 1 can exhibit improved transferability of liquid excreta from the top sheet 2 to the absorber 4.

When the liquid excrement supplied to the top sheet 2 is menstrual blood, the top sheet 2 has a kinematic viscosity at 40 ° C. of 0.01 to 80 mm ² / s and a water retention of 0.01 to 4.0% by mass. It is preferable that a blood slipperiness imparting agent having a weight average molecular weight of less than 1,000 is applied.

  The blood slipperiness-imparting agent is applied to, for example, the surface region 20 of the topsheet 2 or a region including the surface region 20 (for example, substantially the entire skin-side surface of the topsheet 2 or substantially the entire absorbent region) Can do.

  When the blood slipperiness imparting agent is coated on the top sheet 2, the following effects are exhibited. The menstrual blood supplied to the top sheet 2 can slide into the groove 22 (low fiber density region) together with the blood slipperiness imparting agent present in the top sheet 2 and can migrate to the absorbent body 4. Therefore, menstrual blood remaining in the top sheet 2 can be reduced, the sticky feeling of the top sheet 2 can be prevented, and the smooth feeling can be maintained. The effect of such a blood slipperiness-imparting agent is exerted irrespective of changes in menstrual blood discharge (that is, whether menstrual blood discharged at a time is large or small). .

  In addition, since a blood slipperiness | lubricity imparting agent acts also as a lubrication agent and reduces the friction between fibers, the suppleness of the top sheet 2 whole can be improved.

  The sanitary napkin 1 is different from known absorbent articles including skin care compositions, lotion compositions, etc., and does not require components such as emollients and immobilizing agents. It can be applied to the sheet 2.

The basis weight of the blood slipperiness imparting agent is usually about 1 to 30 g / m ² , preferably about ^{2 to 20} g / m ² , more preferably about 3 to 10 g / m ² . When the basis weight of the blood slipperiness-imparting agent is less than about 1 g / m ² , menstrual blood tends to remain in the top sheet 2, while when the basis weight of the blood slipperiness-imparting agent exceeds about 30 g / m ² , The sticky feeling during wearing tends to increase.

The basis weight of the blood slipperiness-imparting agent can be measured, for example, as follows.
(1) The range to be measured of the top sheet is cut out with a sharp blade, for example, a cutter blade, so as not to change its thickness as much as possible, and a sample is obtained.
(2) The area of the sample: SA (m ² ) and the mass: SM ₀ (g) are measured.
(3) The sample is stirred for at least 3 minutes in a solvent capable of dissolving the blood lubricity-imparting agent, such as ethanol, acetone, etc., and the blood lubricity-imparting agent is dissolved in the solvent.
(4) The sample is filtered on the filter paper whose mass has been measured, and the sample is thoroughly washed with a solvent on the filter paper. The sample on the filter paper is dried in an oven at 60 ° C.
(5) The mass of the filter paper and the sample is measured, and the mass of the filter paper is subtracted therefrom to calculate the mass of the sample after drying: SM ₁ (g).
(6) The basis weight BBS (g / m ² ) of the blood lubricity-imparting agent is expressed by the following formula:
BBS (g / m ² ) = [SM ₀ (g) −SM ₁ (g)] / SA (m ² )
Calculated by
In order to reduce the error, a plurality of samples are collected from a plurality of absorbent articles so that the total area of the samples exceeds 100 cm ² , the experiment is repeated a plurality of times, and an average value thereof is adopted.

  It is preferable that the blood slipperiness imparting agent is applied so as not to block the gaps between the fibers of the top sheet 2. For example, the blood slipperiness imparting agent adheres to the surface of the fiber of the top sheet 2 in the form of droplets or particles, or covers the surface of the fiber.

  The blood slipperiness-imparting agent is preferably applied so as to increase its surface area. Thereby, the contact area of a blood slipperiness | lubricity imparting agent and menstrual blood becomes large, and a blood slipperiness | lubricity imparting agent becomes easy to slide down with menstrual blood. When the blood slipperiness-imparting agent is present in the form of droplets or particles, the surface area can be increased by reducing the particle size.

  Examples of the method for applying the blood slipperiness-imparting agent include a method using a coating apparatus (for example, a non-contact type coater such as a spiral coater, curtain coater, spray coater, dip coater, contact type coater, etc.). . A preferred coating apparatus is a non-contact type coater. Thereby, while being able to disperse | distribute the liquid slipperiness | lubricity imparting agent of a droplet form or a particle form to the whole uniformly, the damage given to the top sheet 2 can be reduced.

  The blood slipperiness imparting agent can be applied as a coating liquid containing a volatile solvent, for example, an alcohol solvent, an ester solvent, an aromatic solvent, or the like, if desired. When the coating solution contains a volatile solvent, the viscosity of the coating solution containing the blood slipperiness-imparting agent is lowered, so that the coating process can be simplified, such as easy application and no need for heating during coating. I can plan.

  The blood slipperiness-imparting agent is, for example, a control seam HMA (Hot Melt Adhesive) as it is in the case of a liquid at room temperature or heated to lower the viscosity and heated to be liquefied in the case of a solid at room temperature. ) Can be applied by gun. By increasing the air pressure of the control seam HMA gun, it is possible to apply a particulate blood slipping agent. In addition, the application quantity of a blood slipperiness | lubricity imparting agent can be adjusted by increasing / decreasing the application quantity from a control seam HMA gun, for example.

  The blood slipperiness imparting agent may be applied when the top sheet 2 is produced, or may be applied on the production line of the sanitary napkin 1. From the viewpoint of suppressing capital investment, it is preferable to apply a blood slipperiness-imparting agent in the production line of the sanitary napkin 1, and further suppress the blood slipperiness-imparting agent from dropping and contaminating the line. Therefore, it is preferable to apply the blood slipperiness imparting agent immediately downstream of the production line, specifically, immediately before the product is enclosed in the individual package.

Hereinafter, the blood slipperiness imparting agent will be described in detail.
The blood slipperiness imparting agent has a kinematic viscosity at 40 ° C. of about 0.01 to about 80 mm ² / s, a water retention of about 0.05 to about 4.0% by mass, and a weight average molecular weight of about 1. Less than 1,000.

The kinematic viscosity at 40 ° C. of the blood slipperiness-imparting agent can be appropriately adjusted in the range of about 0 to about 80 mm ² / s, preferably about 1 to about 70 mm ² / s, more preferably about 3 to about 60 mm ² / s, even more preferably from about 5 to about 50 mm ² / s, and even more preferably from about 7 to about 45 mm ² / s. In this specification, the kinematic viscosity at 40 ° C. may be simply referred to as “kinematic viscosity”.

  The kinematic viscosity is as follows: a) as the molecular weight of the blood slipperiness-imparting agent increases, b) polar groups such as carbonyl bond (—CO—), ether bond (—O—), carboxyl group (—COOH), hydroxyl group ( The higher the ratio of -OH), etc., and c) the higher the IOB, the higher the tendency.

In order to have a kinematic viscosity of about 0 to about 80 mm ² / s at 40 ° C., the melting point of the blood slipperiness imparting agent is preferably 45 ° C. or less. This is because when the blood slipperiness-imparting agent contains crystals at 40 ° C., the kinematic viscosity tends to increase.

The significance of kinematic viscosity in the blood slipperiness-imparting agent will be described later. When the kinematic viscosity exceeds about 80 mm ² / s, the blood slipperiness-imparting agent is too viscous to reach the skin contact surface of the top sheet. At the same time, it tends to be difficult to slide from the convex portion to the concave portion and then to move into the absorber.

  The kinematic viscosity can be measured at a test temperature of 40 ° C. using a Canon Fenceke reverse flow viscometer according to “5. Kinematic viscosity test method” of JIS K 2283: 2000.

  The water retention rate of the blood slipperiness-imparting agent can be appropriately adjusted in the range of about 0.01 to about 4.0% by mass, preferably about 0.02 to about 3.5% by mass, more preferably About 0.03 to about 3.0% by weight, even more preferably about 0.04 to about 2.5% by weight, and even more preferably about 0.05 to about 2.0% by weight.

In the present specification, the “water retention” means the ratio (mass) of water that a substance can hold, and can be measured as follows.
(1) Place a 20 mL test tube, a rubber stopper, a substance to be measured, and deionized water in a constant temperature room at 40 ° C. overnight.
(2) In a constant temperature room, 5.0 g of a substance to be measured and 5.0 g of deionized water are put into a test tube.
(3) Put a rubber stopper on the mouth of the test tube in a thermostatic chamber, rotate the test tube once, and let it stand for 5 minutes.
(4) In a thermostatic chamber, 3.0 g of the substance layer to be measured (usually the upper layer) is collected in a glass petri dish having a diameter of 90 mm and a mass of W ₀ (g).
(5) The petri dish is heated in an oven at 105 ° C. for 3 hours to evaporate water, and the whole petri dish is measured for mass: W ₁ (g).
(6) The water retention rate is calculated according to the following formula.
Water retention (mass%) = 100 × [W ₀ (g) −W ₁ (g)] / 3.0 (g)
The measurement is carried out three times and the average value is adopted.

  Although the significance of the water retention rate in the blood slipperiness-imparting agent will be described later, when the water retention rate decreases, the affinity between the blood slipperiness-imparting agent and menstrual blood decreases and reaches the skin contact surface of the top sheet. There is a tendency that it becomes difficult to transfer to the absorbent body with the menstrual blood. On the other hand, when the water retention rate becomes high, the affinity with menstrual blood becomes very high like a surfactant, and the absorbed blood remains on the skin contact surface of the top sheet, and the skin contact of the top sheet The surface tends to be red and easily colored.

  The water retention rate is as follows: a) the smaller the molecular weight of the blood slipperiness agent, and b) polar groups such as carbonyl bond (—CO—), ether bond (—O—), carboxyl group (—COOH), hydroxyl As the ratio of the group (—OH) or the like is higher, the value tends to increase. This is because the blood slipperiness imparting agent is more hydrophilic. Further, the water retention rate tends to increase as the IOB increases, that is, as the inorganic value increases and as the organic value decreases. This is because the blood slipperiness-imparting agent is more hydrophilic.

  The significance of the kinematic viscosity and the water retention rate in the blood slipping agent will be described.

  When menstrual blood excreted from the wearer reaches the excretory opening contact region, it contacts the blood slipperiness imparting agent present in the convex part, slides into the concave part together with this, passes through the top sheet, and moves to the absorber. .

More specifically, the blood slipperiness-imparting agent having a kinematic viscosity of about 0.01 to about 80 mm ² / s at 40 ° C. has a very low viscosity near the body temperature of the wearer and a certain affinity with menstrual blood. Therefore, it is considered that menstrual blood can slide from the convex part to the concave part together with menstrual blood, and can pass through the top sheet and quickly migrate to the absorbent body using the momentum at the time of the sliding. . Further, the blood slipperiness imparting agent present in the convex part has a water retention of about 0.01 to about 4.0% by mass, and therefore has an affinity for mainly hydrophilic components (plasma and the like) in menstrual blood. Therefore, it is considered that menstrual blood hardly remains on the top sheet.

  If there is a large amount of menstrual blood discharged from the wearer, even if the kinetic energy of menstrual blood itself is large and the kinematic viscosity value of the blood slipperiness-imparting agent is relatively high, it is difficult to slip with menstrual blood. Even if the water retention value is relatively high and the affinity with the hydrophilic component of menstrual blood is high, the weight molecular weight value is relatively high and difficult to slide with menstrual blood, and the top sheet Even when there is no uneven structure on the skin contact surface, it is considered that menstrual blood easily migrates to the absorber.

  On the other hand, when the amount of menstrual blood discharged from the wearer is small, menstrual blood has a low kinetic energy, and menstrual blood that has reached the skin contact surface of the top sheet tends to stay on the spot. Accordingly, the blood slipperiness-imparting agent slides down from the convex part to the concave part together with menstrual blood, and draws menstrual blood into the top sheet, and then draws it into the absorber, thereby rapidly transferring menstrual blood to the absorber. be able to.

  The blood slipperiness agent has a weight average molecular weight of less than about 1,000, and preferably has a weight average molecular weight of less than about 900. This is because if the weight average molecular weight is about 1,000 or more, the blood slipperiness-imparting agent itself has tackiness and tends to give the wearer discomfort. In addition, since the viscosity of the blood slipperiness-imparting agent tends to increase as the weight average molecular weight increases, it becomes difficult to lower the viscosity of the blood slipperiness-imparting agent to a viscosity suitable for coating by heating, As a result, the blood slipping agent may have to be diluted with a solvent.

  The blood slipperiness-imparting agent preferably has a weight average molecular weight of about 100 or more, and more preferably has a weight average molecular weight of about 200 or more. This is because when the weight average molecular weight is small, the vapor pressure of the blood slipperiness imparting agent becomes high and vaporizes during storage, causing problems such as a decrease in the amount and odor when worn.

In the present specification, “weight average molecular weight” refers to a polydispersed compound (for example, a compound produced by sequential polymerization, a plurality of fatty acids, and an ester produced from a plurality of aliphatic monohydric alcohols). , A concept that includes a single compound (eg, an ester formed from one fatty acid and one aliphatic monohydric alcohol), and N _i molecules of molecular weight M _i (i = 1, or i = 1, 2, ...), the following formula:
M _w = ΣN _i M _i ² / ΣN _i M _i
Means M _w obtained by

In this specification, a weight average molecular weight means the value of polystyrene conversion calculated | required by gel permeation chromatography (GPC).
Examples of GPC measurement conditions include the following.
Model: Hitachi High-Technologies Corporation High-Performance Liquid Chromatogram Lachrom Elite
Column: SHODEX KF-801, KF-803 and KF-804 manufactured by Showa Denko K.K.
Eluent: THF
Flow rate: 1.0 mL / min Driving amount: 100 μL
Detection: RI (differential refractometer)
In addition, the weight average molecular weight described in the Example of this specification is measured on the said conditions.

The blood slipperiness agent can have an IOB of about 0.00 to about 0.60.
IOB (Inorganic Organic Balance) is an index indicating a balance between hydrophilicity and lipophilicity. In the present specification, the following formula by Oda et al.
IOB = value calculated by inorganic value / organic value.

Inorganic values and organic values are reported in the field of chemistry, Vol. 11, no. 10 (1957) p. 719-725).
Table 1 below summarizes the organic and inorganic values of the major groups by Mr. Fujita.

For example, in the case of an ester of tetradecanoic acid having 14 carbon atoms and dodecyl alcohol having 12 carbon atoms, the organic value is 520 (CH ₂ , 20 × 26), and the inorganic value is 60 (—COOR, 60 × 1), so that IOB = 0.12.

  In the blood slipping agent, the IOB is preferably about 0.00 to about 0.60, more preferably about 0.00 to about 0.50, and about 0.00 to about 0.40. And more preferably from about 0.00 to about 0.30. This is because when the IOB is in the above range, the water holding power and kinematic viscosity easily satisfy the above requirements.

  The blood slipperiness-imparting agent preferably has a melting point of 45 ° C. or lower, and more preferably has a melting point of 40 ° C. or lower. This is because when the blood slipperiness-imparting agent has a melting point of 45 ° C. or less, the blood slipperiness-imparting agent tends to have a kinematic viscosity in the above range.

  In the present specification, the “melting point” means a peak top temperature of an endothermic peak when changing from a solid state to a liquid state when measured with a differential scanning calorimeter at a temperature rising rate of 10 ° C./min. The melting point can be measured using, for example, a DSC-60 type DSC measuring apparatus manufactured by Shimadzu Corporation.

  The blood lubricity-imparting agent may be liquid at room temperature (about 25 ° C.) or solid as long as it has a melting point of about 45 ° C. or lower, ie, a melting point of about 25 ° C. or higher, or It may be less than about 25 ° C. and may have a melting point of, for example, about −5 ° C., about −20 ° C., etc.

  The blood slipperiness imparting agent has a lower melting point, but preferably has a low vapor pressure. The vapor pressure of the blood slipperiness-imparting agent is preferably about 0 to about 200 Pa, more preferably about 0 to about 100 Pa, and further about 0 to about 10 Pa at 25 ° C. (1 atm). Preferably, it is about 0 to about 1 Pa, and even more preferably about 0.0 to about 0.1 Pa.

  Considering that the absorbent article of the present disclosure is used in contact with a human body, the vapor pressure is preferably about 0 to about 700 Pa at 40 ° C. (1 atm), and is about 0 to about 100 Pa. Is more preferably about 0 to about 10 Pa, still more preferably about 0 to about 1 Pa, and still more preferably about 0.0 to about 0.1 Pa. This is because if the vapor pressure of the blood slipperiness imparting agent is high, it may vaporize during storage, and problems such as reduction in the amount and odor during wearing may occur.

  Further, the melting point of the blood slipperiness-imparting agent can be selected according to the climate, the length of wearing time, and the like. For example, in an area where the average temperature is about 10 ° C. or less, by adopting a blood slipperiness imparting agent having a melting point of about 10 ° C. or less, menstrual blood is excreted and then cooled by the ambient temperature. However, it is considered that the blood slipperiness-imparting agent is easy to function.

  Moreover, when the absorbent article is used for a long time, the melting point of the blood slipperiness imparting agent is preferably higher in the range of about 45 ° C. or less. This is because the blood slipperiness-imparting agent is not easily biased even when worn for a long time, and is not easily affected by sweat, friction at the time of wearing.

  In this technical field, the skin contact surface of the top sheet is coated with a surfactant for the purpose of changing the surface tension of menstrual blood and the like and quickly absorbing menstrual blood. However, the top sheet coated with a surfactant has a high affinity with hydrophilic components (such as plasma) in menstrual blood, and tends to attract them and rather cause menstrual blood to remain on the top sheet. Unlike conventionally known surfactants, the blood slipperiness imparting agent has a low affinity for menstrual blood, and can pass the menstrual blood to the absorbent body quickly without remaining on the top sheet.

The blood slipperiness imparting agent is preferably the following (i) to (iii),
(I) hydrocarbons,
(Ii) (ii-1) consisting of a hydrocarbon moiety and (ii-2) a carbonyl group (—CO—) and an oxy group (—O—) inserted between the C—C single bonds of the hydrocarbon moiety. A compound having one or more, the same or different groups, selected from the group, and (iii) (iii-1) a hydrocarbon moiety, and (iii-2) between the C—C single bonds of the hydrocarbon moiety One or a plurality of the same or different groups selected from the group consisting of a carbonyl group (—CO—) and an oxy group (—O—), and (iii-3) a hydrogen atom of the hydrocarbon moiety, A compound having one or a plurality of identical or different groups selected from the group consisting of a carboxyl group (—COOH) and a hydroxyl group (—OH) to be substituted;
As well as any combination thereof.

  In the present specification, “hydrocarbon” means a compound composed of carbon and hydrogen, and a chain hydrocarbon, for example, a paraffinic hydrocarbon (also referred to as an alkane, which does not include a double bond and a triple bond). , Olefinic hydrocarbons (including one double bond, also referred to as alkene), acetylenic hydrocarbons (including one triple bond, also referred to as alkyne), and the group consisting of double and triple bonds And hydrocarbons containing two or more bonds selected from the above, and cyclic hydrocarbons such as aromatic hydrocarbons and alicyclic hydrocarbons.

The hydrocarbon is preferably a chain hydrocarbon and an alicyclic hydrocarbon, more preferably a chain hydrocarbon, paraffinic hydrocarbon, olefinic hydrocarbon, and two or more double bonds. More preferably, it is a hydrocarbon that does not contain a triple bond, and more preferably it is a paraffinic hydrocarbon.
The chain hydrocarbon includes a straight chain hydrocarbon and a branched chain hydrocarbon.

  In the compounds (ii) and (iii), when two or more oxy groups (—O—) are inserted, the oxy groups (—O—) are not adjacent to each other. Therefore, the compounds (ii) and (iii) do not include compounds having a continuous oxy group (so-called peroxides).

  In the compound of (iii), at least one hydrogen atom of the hydrocarbon moiety is more preferably a hydroxyl group (—OH) than a compound in which at least one hydrogen atom of the hydrocarbon moiety is substituted with a carboxyl group (—COOH). ) Is preferred. This is because the carboxyl group binds to a metal or the like in menstrual blood, increases the water retention rate of the blood slipperiness imparting agent, and may exceed a predetermined range. This is the same from the viewpoint of IOB. As shown in Table 1, the carboxyl group binds to menstrual metals and the like, and the inorganic value increases significantly from 150 to 400 or more. Sometimes the value of IOB can be greater than about 0.60.

The blood slipperiness imparting agent is more preferably the following (i ′) to (iii ′),
(I ′) hydrocarbon,
(Ii ′) (ii′-1) a hydrocarbon moiety and (ii′-2) a carbonyl bond (—CO—), an ester bond (—COO— inserted between the C—C single bonds of the hydrocarbon moiety. ), A carbonate bond (—OCOO—), and an ether bond (—O—), one or more compounds having the same or different bonds, and (iii ′) (iii′-1 ) A hydrocarbon moiety and (iii′-2) a carbonyl bond (—CO—), an ester bond (—COO—), a carbonate bond (—OCOO—) inserted between the C—C single bonds of the hydrocarbon moiety. And a carboxyl group (—COOH) that replaces one or more of the same or different bonds selected from the group consisting of an ether bond (—O—) and a hydrogen atom of the hydrocarbon moiety (iii′-3) And a hydroxyl group (-O H) a compound having one or more identical or different groups selected from the group consisting of
As well as any combination thereof.

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

  More preferably, the blood slipperiness-imparting agent is more preferably about 1.8 or less carbonyl bonds (—CO—), 2 or less ester bonds (—COO—) per 10 carbon atoms, About 1.5 or less bonds (-OCOO-), about 6 or less ether bonds (-O-), about 0.8 or less carboxyl groups (-COOH), and / or hydroxyl groups (-OH) About 1.2 or less.

The blood slipperiness imparting agent is more preferably the following (A) to (F),
(A) (A1) a compound having a chain hydrocarbon moiety and 2 to 4 hydroxyl groups replacing hydrogen atoms in the chain hydrocarbon moiety, (A2) a chain hydrocarbon moiety, and a chain carbonization An ester with a compound having one carboxyl group replacing a hydrogen atom of the hydrogen moiety,
(B) (B1) a compound having a chain hydrocarbon moiety and 2 to 4 hydroxyl groups replacing hydrogen atoms in the chain hydrocarbon moiety, (B2) a chain hydrocarbon moiety, and a chain carbonization An ether with a compound having one hydroxyl group replacing a hydrogen atom of the hydrogen moiety,
(C) (C1) a carboxylic acid, a hydroxy acid, an alkoxy acid or an oxo acid containing a chain hydrocarbon moiety and 2 to 4 carboxyl groups that replace a hydrogen atom of the chain hydrocarbon moiety, and (C2 ) An ester of a chain hydrocarbon moiety and a compound having a hydroxyl group replacing a hydrogen atom of the chain hydrocarbon moiety;
(D) an ether bond (—O—), a carbonyl bond (—CO—), an ester bond (—COO—) inserted between the chain hydrocarbon moiety and the C—C single bond of the chain hydrocarbon moiety. And a compound having any one bond selected from the group consisting of a carbonate bond (—OCOO—),
(E) polyoxy C ₃ -C ₆ alkylene glycol or its alkyl ester or alkyl ether, and (F) a chain hydrocarbon,
As well as any combination thereof.
Hereinafter, the blood slipperiness imparting agent according to (A) to (F) will be described in detail.

[(A) (A1) a chain hydrocarbon moiety, a compound having 2 to 4 hydroxyl groups replacing hydrogen atoms in the chain hydrocarbon moiety, (A2) a chain hydrocarbon moiety, and a chain Esters with compounds having one carboxyl group replacing a hydrogen atom in the hydrocarbon moiety]
(A) (A1) a compound having a chain hydrocarbon moiety and 2 to 4 hydroxyl groups replacing hydrogen atoms in the chain hydrocarbon moiety; (A2) a chain hydrocarbon moiety; Esters (hereinafter sometimes referred to as “compound (A)”) with a compound having one carboxyl group that substitutes a hydrogen atom of the hydrogen moiety have the above kinematic viscosity, water retention and weight average molecular weight. As long as it has, all the hydroxyl groups do not need to be esterified.

  (A1) As a compound having a chain hydrocarbon moiety and 2 to 4 hydroxyl groups substituting hydrogen atoms in the chain hydrocarbon moiety (hereinafter sometimes referred to as “compound (A1)”), For example, chain hydrocarbon tetraols such as alkane tetraols such as pentaerythritol, chain hydrocarbon triols such as alkane triols such as glycerin, and chain hydrocarbon diols such as alkane diols such as glycol Is mentioned.

(A2) Examples of the compound having a chain hydrocarbon moiety and one carboxyl group that replaces a hydrogen atom in the chain hydrocarbon moiety include, for example, one hydrogen atom on a hydrocarbon having one carboxyl group ( -COOH) substituted compounds, for example fatty acids.
Examples of the compound (A) include (a ₁ ) an ester of a chain hydrocarbon tetraol and at least one fatty acid, (a ₂ ) an ester of a chain hydrocarbon triol and at least one fatty acid, and (a ₃ ) Esters of chain hydrocarbon diols with at least one fatty acid.

のペンタエリトリトールと脂肪酸とのテトラエステル、次の式（２）：

のペンタエリトリトールと脂肪酸とのトリエステル、次の式（３）：

のペンタエリトリトールと脂肪酸とのジエステル、次の式（４）：

のペンタエリトリトールと脂肪酸とのモノエステルが挙げられる。
（式中、Ｒ¹〜Ｒ⁴は、それぞれ、鎖状炭化水素である） [Ester of (a ₁ ) chain hydrocarbon tetraol and at least one fatty acid]
Examples of the ester of a chain hydrocarbon tetraol and at least one fatty acid include the following formula (1):

Tetraesters of pentaerythritol and fatty acids of the following formula (2):

Triesters of pentaerythritol and fatty acids of the following formula (3):

Diester of pentaerythritol and fatty acid of the following formula (4):

And monoesters of pentaerythritol and fatty acids.
(In the formula, R ^{1 to} R ⁴ are each a chain hydrocarbon)

As fatty acids (R ¹ COOH, R ² COOH, R ³ COOH, and R ⁴ COOH) constituting esters of pentaerythritol and fatty acids, esters of pentaerythritol and fatty acids have kinematic viscosity, water retention and weight average. as long as it satisfies the molecular weight requirement is not particularly limited, for example, saturated fatty acids, for example, saturated fatty acids C ₂ -C _30, for example, acetic acid (C ₂₎ (C ₂ indicates the number of carbon atoms, R ¹ C, R ² C, R ³ C or R ⁴ C, the same applies hereinafter), propanoic acid (C ₃ ), butanoic acid (C ₄ ) and isomers thereof such as 2-methylpropanoic acid ( C ₄ ), pentanoic acid (C ₅ ) and isomers thereof such as 2-methylbutanoic acid (C ₅ ), 2,2-dimethylpropanoic acid (C ₅ ), hexanoic acid (C ₆ ), heptanoic acid (C ₇ ), octanoic acid (C ₈₎ Beauty isomers thereof, e.g., 2-ethylhexanoic acid (C _8), nonanoic acid (C _9), decanoic 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 ), docosanoic acid (C ₂₂ ), tetracosanoic acid (C ₂₄ ), hexacosanoic acid (C ₂₆ ), octacosanoic acid (C ₂₈ ), Triacontanoic acid (C ₃₀ ) and the like, as well as these isomers not listed.

The fatty acid can also be an unsaturated fatty acid. Examples of unsaturated fatty acids include C _{3 to} C ₂₀ unsaturated fatty acids such as monounsaturated fatty acids such as crotonic acid (C ₄ ), myristoleic acid (C ₁₄ ), palmitoleic acid (C ₁₆ ), and olein. Acids (C ₁₈ ), elaidic acid (C ₁₈ ), vaccenic acid (C ₁₈ ), gadoleic acid (C ₂₀ ), eicosenoic acid (C ₂₀ ), etc., diunsaturated fatty acids such as linoleic acid (C ₁₈ ), eicosadiene Triunsaturated fatty acids such as acids (C ₂₀ ) such as linolenic acid such as α-linolenic acid (C ₁₈ ) and γ-linolenic acid (C ₁₈ ), pinolenic acid (C ₁₈ ), eleostearic acid such as , Α-eleostearic acid (C ₁₈ ) and β-eleostearic acid (C ₁₈ ), mead acid (C ₂₀ ), dihomo-γ-linolenic acid (C ₂₀ ), eicosatrienoic acid (C ₂₀ ), etc. Tetraunsaturated fatty acids such as stear Don acid (C _20), arachidonic acid (C _20), eicosatetraenoic acid (C _20), etc., penta unsaturated fatty acids, for example, bosseopentaenoic acid (C _18), such as eicosapentaenoic acid (C _20), as well as their Of the partial hydrogen adduct.

The ester of pentaerythritol and a fatty acid is preferably an ester of pentaerythritol and a fatty acid derived from a saturated fatty acid, that is, an ester of pentaerythritol and a saturated fatty acid, considering the possibility of modification by oxidation or the like. .
Further, the ester of pentaerythritol and fatty acid is preferably a diester, triester or tetraester, more preferably a triester or tetraester, and more preferably a tetraester from the viewpoint of reducing the water retention value. More preferably, it is an ester.

Considering from the viewpoint that the IOB is about 0.00 to about 0.60, in the tetraester of pentaerythritol and fatty acid, the total number of carbon atoms of the fatty acid constituting the tetraester of pentaerythritol and fatty acid, that is, the above formula In (1), the total number of carbon atoms of the R ¹ C, R ² C, R ³ C, and R ⁴ C moieties is preferably about 15 (when the total number of carbon atoms is 15, the IOB is 0.1. 60).

In the tetraester of pentaerythritol and a fatty acid, for example, pentaerythritol, hexanoic acid (C ₆ ), heptanoic acid (C ₇ ), octanoic acid (C ₈ ), for example, 2-ethylhexanoic acid (C ₈ ), nonane Examples include tetraesters with acid (C ₉ ), decanoic acid (C ₁₀ ) and / or dodecanoic acid (C ₁₂ ).

Considering from the viewpoint that the IOB is about 0.00 to about 0.60, in the triester of pentaerythritol and fatty acid, the total number of carbon atoms of the fatty acid constituting the triester of pentaerythritol and fatty acid, that is, the above formula In (2), the total number of carbon atoms in the R ¹ C, R ² C and R ³ C moieties is preferably about 19 or more (when the total number of carbon atoms is 19, IOB is 0.58). ).

Considering from the viewpoint that IOB is about 0.00 to about 0.60, in the diester of pentaerythritol and fatty acid, the total number of carbon atoms of the fatty acid constituting the diester of pentaerythritol and fatty acid, that is, the above formula (3 ), The total number of carbon atoms in the R ¹ C and R ² C moieties is preferably about 22 or more (when the total number of carbon atoms is 22, IOB is 0.59).

Considering from the viewpoint that IOB is about 0.00 to about 0.60, in the monoester of pentaerythritol and fatty acid, the number of carbon atoms of the fatty acid constituting the monoester of pentaerythritol and fatty acid, that is, the above formula (4 ), The number of carbon atoms in the R ¹ C moiety is preferably about 25 or more (when the number of carbon atoms is 25, IOB is 0.60).
In the calculation of IOB, the influence of double bond, triple bond, iso branch, and tert branch is not considered (the same applies hereinafter).

  Examples of commercially available esters of pentaerythritol and fatty acids include Unistar H-408BRS, H-2408BRS-22 (mixed product), and the like (manufactured by NOF Corporation).

のグリセリンと脂肪酸とのトリエステル、次の式（６）：

のグリセリンと脂肪酸とのジエステル、及び次の式（７）：

（式中、Ｒ⁵〜Ｒ⁷は、それぞれ、鎖状炭化水素である）
のグリセリンと脂肪酸とのモノエステルが挙げられる。 [Ester of (a ₂ ) chain hydrocarbon triol and at least one fatty acid]
Examples of the ester of a chain hydrocarbon triol and at least one fatty acid include the following formula (5):

Triester of glycerin and fatty acid of the following formula (6):

Diesters of glycerin and fatty acids and the following formula (7):

(Wherein R ^{5 to} R ⁷ are each a chain hydrocarbon)
And monoesters of glycerin and fatty acids.

As fatty acids (R ⁵ COOH, R ⁶ COOH and R ⁷ COOH) constituting esters of glycerin and fatty acids, the esters of glycerin and fatty acids satisfy the requirements of kinematic viscosity, water retention and weight average molecular weight. If there is, there is no particular limitation, for example, fatty acids listed in “esters of (a ₁ ) chain hydrocarbon tetraol and at least one fatty acid”, that is, saturated fatty acids and unsaturated fatty acids, oxidation, etc. In view of the possibility of modification by the above, it is preferably an ester of glycerin and a fatty acid derived from a saturated fatty acid, that is, an ester of glycerin and a saturated fatty acid.

  Moreover, as ester of glycerol and a fatty acid, it is preferable that it is a diester or a triester from a viewpoint of making the value of a water retention small, and it is more preferable that it is a triester.

Triesters of glycerin and fatty acids are also called triglycerides, for example, triesters of glycerin and octanoic acid (C ₈ ), triesters of glycerin and decanoic acid (C ₁₀ ), glycerin and dodecanoic acid (C ₁₂ ). And triesters of glycerin with 2 or 3 fatty acids, and mixtures thereof.

Examples of triesters of glycerin and two or more fatty acids include triesters of glycerin and octanoic acid (C ₈ ) and decanoic acid (C ₁₀ ), glycerin, octanoic acid (C ₈ ), and decanoic acid. (C ₁₀ ) and triester with dodecanoic acid (C ₁₂ ), glycerin and octanoic acid (C ₈ ), decanoic acid (C ₁₀ ), dodecanoic acid (C ₁₂ ), tetradecanoic acid (C ₁₄ ), hexadecanoic acid ( And a triester with C ₁₆ ) and octadecanoic acid (C ₁₈ ).

Considering from the viewpoint that the melting point is about 45 ° C. or less, the triester of glycerin and a fatty acid is the total number of carbon atoms of the fatty acid constituting the triester of glycerin and a fatty acid, that is, in formula (5), R ⁵ C , R ⁶ C and R ⁷ C moieties preferably have a total carbon number of about 40 or less.

Considering from the viewpoint that the IOB is about 0.00 to about 0.60, in the triester of glycerin and fatty acid, the total number of carbon atoms of the fatty acid constituting the triester of glycerin and fatty acid, that is, formula (5) The total number of carbon atoms of the R ⁵ C, R ⁶ C and R ⁷ C moieties is preferably about 12 or more (when the total number of carbon atoms is 12, IOB is 0.60).
A triester of glycerin and a fatty acid is a so-called fat and is a component that can constitute a human body, and thus is preferable from the viewpoint of safety.

  Commercial products of triesters of glycerin and fatty acid include tricoconut oil fatty acid glyceride, NA36, panacet 800, panacet 800B and panacet 810S, and tri-C2L oil fatty acid glyceride and tri-CL oil fatty acid glyceride (manufactured by NOF Corporation). Etc.

Diesters of glycerin and fatty acids are also called diglycerides, for example, diesters of glycerin and decanoic acid (C ₁₀ ), diesters of glycerin and dodecanoic acid (C ₁₂ ), diesters of glycerin and hexadecanoic acid (C ₁₆ ). And diesters of glycerin and two fatty acids, and mixtures thereof.

Considering from the viewpoint that IOB is about 0.00 to about 0.60, in the diester of glycerin and fatty acid, the total number of carbon atoms of the fatty acid constituting the diester of glycerin and fatty acid, that is, in the formula (6), The total number of carbon atoms in the R ⁵ C and R ⁶ C moieties is preferably about 16 or more (when the total number of carbon atoms is 16, IOB is 0.58).

Monoesters of glycerin and fatty acids are also referred to as monoglycerides, and examples include glycerin octadecanoic acid (C ₁₈ ) monoester, glycerin docosanoic acid (C ₂₂ ) monoester, and the like.

Considering from the viewpoint that IOB is about 0.00 to about 0.60, in the monoester of glycerin and fatty acid, the number of carbon atoms of the fatty acid constituting the monoester of glycerin and fatty acid, that is, in the formula (7), The number of carbon atoms in the R ⁵ C moiety is preferably about 19 or more (when the number of carbon atoms is 19, IOB is 0.59).

[Ester of (a ₃ ) chain hydrocarbon diol and at least one fatty acid]
Examples of the ester of a chain hydrocarbon diol and at least one fatty acid include C _{2 to} C ₆ chain hydrocarbon diols such as C _{2 to} C ₆ glycols such as ethylene glycol, propylene glycol, and butylene glycol. , Monoester or diester of pentylene glycol or hexylene glycol and a fatty acid.

Specifically, as an ester of a chain hydrocarbon diol and at least one fatty acid, for example, the following formula (8):
R ⁸ COOC _k H _2k OCOR ⁹ (8)
(Wherein k is an integer from 2 to 6 and R ⁸ and R ⁹ are each a chain hydrocarbon)
A diester of a C ₂ -C ₆ glycol and a fatty acid, and the following formula (9):
R ⁸ COOC _k H _2k OH (9)
(Wherein k is an integer from 2 to 6 and R ⁸ is a chain hydrocarbon)
And monoesters of C ₂ -C ₆ glycols and fatty acids.

In the ester of C ₂ -C ₆ glycol and fatty acid, the fatty acid to be esterified (corresponding to R ⁸ COOH and R ⁹ COOH in formula (8) and formula (9)) is C ₂ -C ₆ glycol and The ester with a fatty acid is not particularly limited as long as it satisfies the requirements of kinematic viscosity, water retention and weight average molecular weight. For example, “(a ₁ ) a chain hydrocarbon tetraol and at least one fatty acid The fatty acids listed in “Ester”, that is, saturated fatty acids and unsaturated fatty acids are mentioned, and saturated fatty acids are preferred in consideration of the possibility of modification by oxidation or the like.

Considering from the viewpoint of setting the IOB to about 0.00 to about 0.60, in the diester of butylene glycol (k = 4) and a fatty acid represented by the formula (8), the carbon number of the R ⁸ C and R ⁹ C moieties Is preferably about 6 or more (when the total number of carbon atoms is 6, IOB is 0.60).

Considering from the viewpoint that IOB is about 0.00 to about 0.60, in the monoester of ethylene glycol (k = 2) and a fatty acid represented by formula (9), the carbon number of the R ⁸ C moiety is about It is preferably 12 or more (when the carbon number is 12, IOB is 0.57).

The esters of C ₂ -C ₆ glycol and fatty acids, in consideration of the potential for degradation by oxidation and the like, derived from saturated fatty acids, esters of C ₂ -C ₆ glycol and fatty acid, Nachi Suwa, C ₂ ~ An ester of C ₆ glycol and a saturated fatty acid is preferred.

As the ester of a C ₂ -C ₆ glycols and fatty acid esters from the viewpoint of reducing the value of the water holding percentage, from large glycol number of carbon atoms, a glycol and a fatty acid, for example, butylene glycol, pentylene An ester of glycol and fatty acid derived from glycol or hexylene glycol is preferable.
Furthermore, the ester of C ₂ -C ₆ glycol and a fatty acid is preferably a diester from the viewpoint of reducing the water retention value.
Examples of commercially available esters of C ₂ -C ₆ glycol and fatty acid include Compol BL and Compol BS (manufactured by NOF Corporation).

[(B) (B1) a compound having a chain hydrocarbon moiety and 2 to 4 hydroxyl groups substituting for hydrogen atoms in the chain hydrocarbon moiety, (B2) a chain hydrocarbon moiety, and a chain Ether with a compound having one hydroxyl group replacing a hydrogen atom of the hydrocarbon moiety]
(B) (B1) a compound having a chain hydrocarbon moiety and 2 to 4 hydroxyl groups replacing hydrogen atoms in the chain hydrocarbon moiety, (B2) a chain hydrocarbon moiety, and a chain carbonization The ether (hereinafter sometimes referred to as “compound (B)”) with a compound having one hydroxyl group substituting a hydrogen atom in the hydrogen moiety has the above kinematic viscosity, water retention and weight average molecular weight. As long as it has, all the hydroxyl groups do not need to be etherified.

  (B1) As a compound having a chain hydrocarbon moiety and 2 to 4 hydroxyl groups substituting hydrogen atoms in the chain hydrocarbon moiety (hereinafter sometimes referred to as “compound (B1)”), What is enumerated as a compound (A1) in "Compound (A)", for example, a pentaerythritol, glycerol, and glycol are mentioned.

  Examples of the compound (B2) having a chain hydrocarbon moiety and one hydroxyl group substituting a hydrogen atom of the chain hydrocarbon moiety (hereinafter sometimes referred to as “compound (B2)”) include: A compound in which one hydrogen atom of a hydrocarbon is substituted with one hydroxyl group (—OH), for example, an aliphatic monohydric alcohol, for example, a saturated aliphatic monohydric alcohol and an unsaturated aliphatic monohydric alcohol Can be mentioned.

Examples of the saturated aliphatic monohydric alcohol include C _{1 to} C ₂₀ saturated aliphatic monohydric alcohols such as methyl alcohol (C ₁ ) (C ₁ represents the number of carbon atoms, the same shall apply hereinafter), ethyl alcohol (C ₂ ), propyl alcohol (C ₃ ) and isomers thereof such as isopropyl alcohol (C ₃ ), butyl alcohol (C ₄ ) and isomers thereof such as sec-butyl alcohol (C ₄ ) and tert-butyl alcohol ( C ₄ ), pentyl alcohol (C ₅ ), hexyl alcohol (C ₆ ), heptyl alcohol (C ₇ ), octyl alcohol (C ₈ ) and isomers thereof such as 2-ethylhexyl alcohol (C ₈ ), nonyl alcohol ( C _9), decyl alcohol (C _10), dodecyl alcohol (C _12), tetradecyl alcohol (C _14), hexyl Decyl alcohol (C _16), heptadecyl alcohol (C ₁₇₎ to, octadecyl alcohol (C _18), and eicosyl alcohol (C _20), and isomers thereof that are not listed.

  Examples of the unsaturated aliphatic monohydric alcohol include those obtained by substituting one of the C—C single bonds of the saturated aliphatic monohydric alcohol with a C═C double bond, for example, oleyl alcohol. It is commercially available from Rika Co., Ltd. under the names of the Rica Coal series and the Angelo All series.

Examples of the compound (B) include (b ₁ ) ethers of chain hydrocarbon tetraol and at least one aliphatic monohydric alcohol, such as monoether, diether, triether and tetraether, preferably diether, triether. Ethers and tetraethers, more preferably triethers and tetraethers, and even more preferably tetraethers, ethers of (b ₂ ) chain hydrocarbon triols and at least one aliphatic monohydric alcohol, such as monoethers, diethers and Triethers, preferably diethers and triethers, and more preferably triethers, and (b ₃ ) ethers of chain hydrocarbon diols with at least one aliphatic monohydric alcohol, such as monoethers and diethers, and preferably Diether It is below.

（式中、Ｒ¹⁰〜Ｒ¹³は、それぞれ、鎖状炭化水素である。）
の、ペンタエリトリトールと脂肪族１価アルコールとのテトラエーテル、トリエーテル、ジエーテル及びモノエーテルが挙げられる。 Examples of ethers of chain hydrocarbon tetraols and at least one aliphatic monohydric alcohol include, for example, the following formulas (10) to (13):

(In the formula, R ^{10 to} R ¹³ are each a chain hydrocarbon.)
And tetraethers, triethers, diethers and monoethers of pentaerythritol and aliphatic monohydric alcohols.

（式中、Ｒ¹⁴〜Ｒ¹⁶は、それぞれ、鎖状炭化水素である。）
の、グリセリンと脂肪族１価アルコールとのトリエーテル、ジエーテル及びモノエーテルが挙げられる。 Examples of ethers of chain hydrocarbon triols and at least one aliphatic monohydric alcohol include, for example, the following formulas (14) to (16):

(In the formula, R ^{14 to} R ¹⁶ are each a chain hydrocarbon.)
And triether, diether and monoether of glycerin and aliphatic monohydric alcohol.

As an ether of a chain hydrocarbon diol and at least one aliphatic monohydric alcohol, the following formula (17):
R ¹⁷ OC _n H _2n OR ¹⁸ (17)
(Wherein n is an integer from 2 to 6 and R ¹⁷ and R ¹⁸ are each a chain hydrocarbon)
A diether of a C ₂ -C ₆ glycol and an aliphatic monohydric alcohol, and the following formula (18):
R ¹⁷ OC _n H _2n OH (18)
(Wherein n is an integer from 2 to 6 and R ¹⁷ is a chain hydrocarbon)
And a monoether of a C ₂ -C ₆ glycol and an aliphatic monohydric alcohol.

Considering from the viewpoint that the IOB is about 0.00 to about 0.60, the tetraether of pentaerythritol and an aliphatic monohydric alcohol is aliphatic 1 constituting the tetraether of pentaerythritol and an aliphatic monohydric alcohol. The total number of carbon atoms of the hydric alcohol, that is, in the above formula (10), the total number of carbon atoms of the R ¹⁰ , R ¹¹ , R ¹² and R ¹³ moieties is preferably about 4 or more (the total number of carbon atoms is In the case of 4, the IOB is 0.44).

Considering from the viewpoint that IOB is about 0.00 to about 0.60, the triether of pentaerythritol and aliphatic monohydric alcohol is aliphatic 1 constituting the triether of pentaerythritol and aliphatic monohydric alcohol. The total number of carbon atoms of the monohydric alcohol, that is, in the above formula (11), the total number of carbon atoms of the R ¹⁰ , R ¹¹ and R ¹² portions is preferably about 9 or more (when the total number of carbon atoms is 9 IOB becomes 0.57).

Considering from the viewpoint that the IOB is about 0.00 to about 0.60, diether of pentaerythritol and aliphatic monohydric alcohol is an aliphatic monohydric alcohol constituting a diether of pentaerythritol and aliphatic monohydric alcohol. That is, in the above formula (12), the total number of carbon atoms in the R ¹⁰ and R ¹¹ moieties is preferably about 15 or more (when the total number of carbon atoms is 15, the IOB is 0). .60).

Considering from the viewpoint that the IOB is about 0.00 to about 0.60, the monoether of pentaerythritol and aliphatic monohydric alcohol is aliphatic 1 constituting the monoether of pentaerythritol and aliphatic monohydric alcohol. the number of carbon atoms of the polyhydric alcohol, i.e., in formula (13), the number of carbon atoms of R ¹⁰ moiety is preferably about 22 or more (when the number of carbon atoms is 22, IOB is 0.59).

Further, from the viewpoint of setting the IOB from about 0.00 to about 0.60, the triether of glycerin and aliphatic monohydric alcohol is aliphatic 1 constituting the triether of glycerin and aliphatic monohydric alcohol. In the formula (14), the total number of carbon atoms of the R ¹⁴ , R ¹⁵ and R ¹⁶ moieties is preferably about 3 or more (when the total number of carbon atoms is 3). , IOB becomes 0.50).

Considering from the viewpoint that IOB is about 0.00 to about 0.60, diether of glycerin and aliphatic monohydric alcohol is carbon of aliphatic monohydric alcohol constituting diether of glycerin and aliphatic monohydric alcohol. In the formula (15), the total number of carbon atoms in the R ¹⁴ and R ¹⁵ moieties is preferably about 9 or more (when the total number of carbon atoms is 9, the IOB is 0.58). Become).

Considering from the viewpoint that the IOB is about 0.00 to about 0.60, in the monoether of glycerin and aliphatic monohydric alcohol, the aliphatic monohydric alcohol constituting the monoether of glycerin and aliphatic monohydric alcohol In the formula (16), the carbon number of the R ¹⁴ moiety is preferably about 16 or more (when the carbon number is 16, IOB is 0.58).

Considering from the viewpoint that IOB is about 0.00 to about 0.60, in the diether of butylene glycol (n = 4) and aliphatic monohydric alcohol represented by the formula (17), R ¹⁷ and R ¹⁸ moieties The total number of carbons is preferably about 2 or more (when the total number of carbons is 2, IOB is 0.33).
Further, considering from the viewpoint of about 0.00 to about 0.60 the IOB, the monoether of ethylene glycol (n = 2) and the aliphatic monohydric alcohol represented by the formula (18), the R ¹⁷ moieties The number of carbon atoms is preferably about 8 or more (when the number of carbon atoms is 8, IOB is 0.60).

  The compound (B) can be produced by dehydrating and condensing the compound (B1) and the compound (B2) in the presence of an acid catalyst.

[(C) (C1) a carboxylic acid, a hydroxy acid, an alkoxy acid or an oxo acid containing a chain hydrocarbon moiety and 2 to 4 carboxyl groups replacing a hydrogen atom of the chain hydrocarbon moiety; C2) Esters of a compound having a chain hydrocarbon moiety and one hydroxyl group replacing a hydrogen atom of the chain hydrocarbon moiety]
(C) (C1) a carboxylic acid, a hydroxy acid, an alkoxy acid or an oxo acid containing a chain hydrocarbon moiety and 2 to 4 carboxyl groups that replace a hydrogen atom of the chain hydrocarbon moiety, and (C2 ) An ester (hereinafter sometimes referred to as “compound (C)”) of a compound having a chain hydrocarbon moiety and one hydroxyl group substituting a hydrogen atom of the chain hydrocarbon moiety is the above-mentioned All carboxyl groups may not be esterified as long as they have kinematic viscosity, water retention and weight average molecular weight.

  (C1) Carboxylic acid, hydroxy acid, alkoxy acid or oxo acid (hereinafter referred to as “compound (C1)” containing a chain hydrocarbon moiety and 2 to 4 carboxyl groups replacing the hydrogen atom of the chain hydrocarbon moiety. ) "May be referred to as, for example, a chain hydrocarbon carboxylic acid having 2 to 4 carboxyl groups, such as a chain hydrocarbon dicarboxylic acid, such as an alkanedicarboxylic acid, such as ethanedioic acid, Propanedioic acid, butanedioic acid, pentanedioic acid, hexanedioic acid, heptanedioic acid, octanedioic acid, nonanedioic acid and decanedioic acid, chain hydrocarbon tricarboxylic acid such as alkanetricarboxylic acid such as propanetriacid , Butanetriacid, pentanetriacid, hexanetriacid, heptanetriacid, octanetriacid, nonanetriacid and decanetriacid, and chain hydrocarbon tetracarboxylic Examples include acids such as alkanetetracarboxylic acids such as butanetetraacid, pentanetetraacid, hexanetetraacid, heptanetetraacid, octanetetraacid, nonanetetraacid and decanetetraacid.

In addition, the compound (C1) includes a chain hydrocarbon hydroxy acid having 2 to 4 carboxyl groups, for example, a chain chain having 2 to 4 carboxyl groups such as malic acid, tartaric acid, citric acid, and isocitric acid. Hydrocarbon alkoxy acids such as O-acetylcitric acid and chain hydrocarbon oxoacids having 2 to 4 carboxyl groups are included.
(C2) Examples of the compound having a chain hydrocarbon moiety and one hydroxyl group substituting a hydrogen atom of the chain hydrocarbon moiety include those listed in the section of “Compound (B)”, for example, fat Group monohydric alcohols.

As the compound (C), (c ₁ ) an ester of a linear hydrocarbon tetracarboxylic acid having 4 carboxyl groups, a hydroxy acid, an alkoxy acid or an oxo acid and at least one aliphatic monohydric alcohol, for example, Monoesters, diesters, triesters and tetraesters, preferably diesters, triesters and tetraesters, more preferably triesters and tetraesters, and even more preferably tetraesters, (c ₂ ) a chain having three carboxyl groups Esters of hydrocarbon tricarboxylic acids, hydroxy acids, alkoxy acids or oxo acids with at least one aliphatic monohydric alcohol, such as monoesters, diesters and triesters, preferably diesters and triesters, and more preferably triesters And ( ₃₎ chain hydrocarbon dicarboxylic acids having two carboxyl groups, hydroxy acids, esters of alkoxy acids or oxoacids, and at least one aliphatic monohydric alcohol, for example, mono- and diesters, preferably include diester It is done.
Examples of compound (C) include dioctyl adipate, tributyl O-acetylcitrate and the like, and are commercially available.

[(D) an ether bond (—O—), a carbonyl bond (—CO—), an ester bond (—COO— inserted between a chain hydrocarbon moiety and a C—C single bond of the chain hydrocarbon moiety. , And any one bond selected from the group consisting of carbonate bonds (—OCOO—)]
(D) an ether bond (—O—), a carbonyl bond (—CO—), an ester bond (—COO—) inserted between the chain hydrocarbon moiety and the C—C single bond of the chain hydrocarbon moiety. And a compound having any one bond selected from the group consisting of a carbonate bond (—OCOO—) (hereinafter sometimes referred to as “compound (D)”), (d ₁ ) aliphatic 1 And ethers of monohydric alcohols and aliphatic monohydric alcohols, (d ₂ ) dialkyl ketones, (d ₃ ) esters of fatty acids and aliphatic monohydric alcohols, and (d ₄ ) dialkyl carbonates.

[(D ₁ ) Ether of aliphatic monohydric alcohol and aliphatic monohydric alcohol]
As an ether of an aliphatic monohydric alcohol and an aliphatic monohydric alcohol, the following formula (19):
R ¹⁹ OR ²⁰ (19)
(In the formula, R ¹⁹ and R ²⁰ are each a chain hydrocarbon)
The compound which has is mentioned.

As the aliphatic monohydric alcohol constituting the ether (corresponding to R ¹⁹ OH and R ²⁰ OH in the formula (19)), the ether satisfies the above-mentioned requirements for kinematic viscosity, water retention and weight average molecular weight. If it is, it will not restrict | limit in particular, For example, the aliphatic monohydric alcohol enumerated by the term of "compound (B)" is mentioned.

[(D ₂ ) dialkylketone]
As the dialkyl ketone, the following formula (20):
R ²¹ COR ²² (20)
(Wherein R ²¹ and R ²² are each an alkyl group)
The compound which has is mentioned.
In addition to being commercially available, the dialkyl ketone can be obtained by a known method, for example, by oxidizing a secondary alcohol with chromic acid or the like.

[(D ₃ ) ester of fatty acid and aliphatic monohydric alcohol]
Examples of the ester of a fatty acid and an aliphatic monohydric alcohol include the following formula (21):
R ²³ COOR ²⁴ (21)
(Wherein R ²³ and R ²⁴ are each a chain hydrocarbon)
The compound which has is mentioned.

Examples of the fatty acid constituting the ester (corresponding to R ²³ COOH in the formula (21)) include, for example, the fatty acids listed in “(a ₁ ) ester of chain hydrocarbon tetraol and fatty acid”, that is, Saturated fatty acids or unsaturated fatty acids are exemplified, and saturated fatty acids are preferred in consideration of the possibility of modification by oxidation or the like. Examples of the aliphatic monohydric alcohol constituting the ester (corresponding to R ²⁴ OH in formula (21)) include the aliphatic monohydric alcohols listed in the section “Compound (B)”.

Examples of esters of fatty acids and aliphatic monohydric alcohols include, for example, dodecanoic acid (C ₁₂ ), dodecyl alcohol (C ₁₂ ) ester, tetradecanoic acid (C ₁₄ ), dodecyl alcohol (C ₁₂ ) and Examples of commercially available esters of fatty acids and aliphatic monohydric alcohols include Electol WE20 and Electol WE40 (manufactured by NOF Corporation).

[(D ₄ ) dialkyl carbonate]
As the dialkyl carbonate, the following formula (22):
R ²⁵ OC (= O) OR ²⁶ (22)
(Wherein R ²⁵ and R ²⁶ are each an alkyl group)
The compound which has is mentioned.
The dialkyl carbonate is commercially available, and can be synthesized by a reaction of phosgene with an alcohol, a reaction of a formic chloride ester with an alcohol or an alcoholate, and a reaction of silver carbonate with an alkyl iodide.

Considering from the viewpoint of water retention, vapor pressure, etc., (d ₁ ) an ether of an aliphatic monohydric alcohol and an aliphatic monohydric alcohol, (d ₂ ) a dialkyl ketone, (d ₃ ) a fatty acid and an aliphatic monohydric alcohol And (d ₄ ) dialkyl carbonates preferably have a weight average molecular weight of about 100 or more, and more preferably about 200 or more.
In (d ₂ ) dialkyl ketone, when the total number of carbon atoms is about 8, for example, for 5-nonanone, the melting point is about −50 ° C., and the vapor pressure is about 230 Pa at 20 ° C.

[(E) polyoxy C ₃ -C ₆ alkylene glycol, or alkyl ester or alkyl ether thereof]
(E) Polyoxy C ₃ -C ₆ alkylene glycol, or alkyl ester or alkyl ether thereof (hereinafter sometimes referred to as compound (E)) includes (e ₁ ) polyoxy C ₃ -C ₆ alkylene glycol, (e ₂ ) Esters of polyoxy C ₃ -C ₆ alkylene glycol and at least one fatty acid; (e ₃ ) ethers of polyoxy C ₃ -C ₆ alkylene glycol and at least one aliphatic monohydric alcohol. This will be described below.

[(E ₁ ) polyoxy C ₃ -C ₆ alkylene glycol]
The polyoxy C ₃ -C ₆ alkylene glycol is any one selected from the group consisting of i) an oxy C ₃ -C ₆ alkylene skeleton, that is, an oxypropylene skeleton, an oxybutylene skeleton, an oxypentylene skeleton, and an oxyhexylene skeleton. A homopolymer having one skeleton and having hydroxy groups at both ends, ii) a block copolymer having two or more skeletons selected from the above group and having hydroxy groups at both ends, or iii) the above group Means a random copolymer having two or more skeletons selected from the above and having hydroxy groups at both ends.

The polyoxy C ₃ -C ₆ alkylene glycol has the following formula (23):
_{HO- (C m H 2m O)} n -H (23)
(In the formula, m is an integer of 3 to 6)
Is represented by

As a result of confirmation by the present inventor, polypropylene glycol (corresponding to a homopolymer of m = 3 in the formula (23)) satisfies the water retention requirement when the weight average molecular weight is less than about 1,000. I found nothing. Therefore, the range of the blood slipperiness-imparting agent does not include a homopolymer of polypropylene glycol, and propylene glycol is included in (e ₁ ) polyoxy C ₃ -C ₆ alkylene glycol as a copolymer or random polymer with other glycols. Should.

  As a result of confirmation by the present inventor, polyethylene glycol (corresponding to a homopolymer of m = 2 in the formula (23)) has a weight average molecular weight of less than 1,000 and satisfies the requirements for kinematic viscosity and water retention. It was suggested that it could not be satisfied.

  Considering from the viewpoint of setting the IOB from about 0.00 to about 0.60, for example, when the formula (23) is polybutylene glycol (m = 4 homopolymer), n ≧ about 7. Preferred (when n = 7, the IOB is 0.57).

Examples of commercial products of poly C ₃ -C ₆ alkylene glycol, e.g., UNIOL (TM) PB-500 and PB-700 (manufactured by NOF Corp.).

[(E ₂ ) ester of polyoxy C ₃ -C ₆ alkylene glycol and at least one fatty acid]
Examples of the ester of polyoxy C ₃ -C ₆ alkylene glycol and at least one fatty acid include the OH terminal of polyoxy C ₃ -C ₆ alkylene glycol described in the section “(e ₁ ) polyoxy C ₃ -C ₆ alkylene glycol”. One or both are esterified with fatty acids, ie monoesters and diesters.

Examples of the fatty acid to be esterified in the ester of polyoxy C ₃ -C ₆ alkylene glycol and at least one fatty acid are listed in “Ester of (a ₁ ) chain hydrocarbon tetraol and at least one fatty acid”. Fatty acid, that is, saturated fatty acid or unsaturated fatty acid, and saturated fatty acid is preferable in consideration of possibility of modification by oxidation or the like.

[(E ₃ ) ether of polyoxy C ₃ -C ₆ alkylene glycol and at least one aliphatic monohydric alcohol]
The ether of polyoxy C ₃ -C ₆ alkylene glycol and at least one aliphatic monohydric alcohol, polyoxy C ₃ -C ₆ alkylene glycol is described in the section "(e ₁₎ polyoxy C ₃ -C ₆ alkylene glycol" And those in which one or both of the OH ends are etherified with an aliphatic monohydric alcohol, that is, monoethers and diethers.
In the ether of polyoxy C ₃ -C ₆ alkylene glycol and at least one aliphatic monohydric alcohol, examples of the aliphatic monohydric alcohol to be etherified include, for example, the aliphatic compounds listed in the section of “Compound (B)”. A monohydric alcohol is mentioned.

[(F) chain hydrocarbon]
Examples of the chain hydrocarbon include (f ₁ ) chain alkanes such as straight chain alkanes and branched chain alkanes. The linear alkane has a carbon number of about 22 or less when the melting point is about 45 ° C. or less, and about 13 or less when the vapor pressure is about 0.01 Pa or less at 1 atm and 25 ° C. That's it. Branched-chain alkanes tend to have lower melting points at the same carbon number than straight-chain alkanes. Therefore, the branched chain alkane can include those having 22 or more carbon atoms even when the melting point is about 45 ° C. or lower.
As a commercial item of hydrocarbons, for example, Pearl Ream 6 (NOF Corporation) can be mentioned.
The blood slipperiness-imparting agent may be applied alone to at least the convex portion 8 in the excretory opening contact region 20, or the blood slipperiness-imparting agent and at least one other component are contained. A blood slipping agent-containing composition may be applied.

  Hereinafter, the blood slipping agent-containing composition will be described. In addition, since it is the same as that of the blood slipperiness | lubricity imparting agent about application of a blood slipperiness | lubricity imparting agent containing composition, description is abbreviate | omitted.

[Blood lubricity-containing composition]
The composition for containing a blood slipperiness agent contains the above-described blood slipperiness imparting agent and at least one other component. The other components are not particularly limited as long as they do not inhibit the effect of the blood slipperiness-imparting agent, and those conventionally used in absorbent articles, particularly top sheets, can be used in the industry. .

  Examples of other components include silicone oil, silicone, and silicone resin.

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

Examples of other components include vitamins such as natural vitamins and synthetic vitamins. Examples of vitamins include water-soluble vitamins such as vitamin B groups, 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. And vitamin C.

  Examples of vitamins include fat-soluble vitamins such as vitamin A group, vitamin D group, vitamin E group, and vitamin K group. Vitamins also include their derivatives.

  Examples of other components include amino acids such as alanine, arginine, lysine, histidine, proline, hydroxyproline, and peptides.

  Other components include, for example, zeolites such as natural zeolites such as fluorite, chabazite, pyroxenite, natrolite, zeolitic and somosonite, and synthetic zeolites.

  Examples of other components include cholesterol, hyaluronic acid, lecithin, ceramide and the like.

  Examples of other components include drugs such as skin astringents, anti-acne agents, anti-wrinkle agents, anti-cellulite agents, whitening agents, antibacterial agents, anti-fungal agents and the like.

  Examples of skin astringents include oil-soluble skin astringents such as zinc oxide, aluminum sulfate, and tannic acid, such as oil-soluble polyphenols. Examples of oil-soluble polyphenols include natural oil-soluble polyphenols, such as buckwheat extract, hypericum extract, nettle extract, chamomile extract, burdock extract, salvia extract, linden extract, scallop extract, birch extract, cedar extract, sage extract, salvia extract, Examples include teuchigurumi extract, hibiscus extract, loquat leaf extract, bodaiju extract, hop extract, marronnier extract, and yokuinin extract.

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

  Examples of the anti-wrinkle agent include lactic acid, salicylic acid, salicylic acid derivatives, glycolic acid, phytic acid, lipoic acid, and lysophosphatide acid.

  Examples of the anti-cellulite agent include xanthine compounds such as aminophylline, caffeine, theophylline, theobromine and the like.

  Examples of the whitening agent include niacinamide, kojic acid, arbutin, glucosamine and derivatives, phytosterol derivatives, ascorbic acid and derivatives thereof, and mulberry extract and placenta extract.

  Examples of other components include anti-inflammatory components, pH adjusters, antibacterial agents, moisturizers, fragrances, pigments, dyes, pigments, plant extracts and the like.

  Anti-inflammatory components include, for example, naturally-occurring anti-inflammatory agents such as buttons, ogon, hypericum, chamomile, licorice, momonoha, mugwort, perilla extract, synthetic anti-inflammatory agents such as allantoin, dipotassium glycyrrhizinate, etc. .

  Examples of the pH adjuster include those for keeping the skin weakly acidic, such as malic acid, succinic acid, citric acid, tartaric acid, and lactic acid.

  Examples of the pigment include titanium oxide.

  The blood slipping agent-containing composition preferably contains about 50 to about 99% by weight and about 1 to about 50% by weight, more preferably about 60%, of the blood slipping agent and at least one other component, respectively. To about 99% and about 1 to about 40%, more preferably about 70 to about 99% and about 1 to about 30%, even more preferably about 80 to about 99% and about 1 to about 20%. % By weight, even more preferably from about 90 to 99% by weight and from about 1 to about 10% by weight, even more preferably from about 95 to 99% by weight and from about 1 to about 5% by weight. This is from the viewpoint of the effect of the blood slipperiness-imparting agent and other components.

The blood slipping agent-containing composition preferably contains a surfactant in an amount equal to or less than the amount derived from the hydrophilic treatment of the top sheet or the second sheet. More specifically, the composition containing a blood slipperiness agent preferably contains a surfactant, preferably about 0.0 to about 1.0 g / m ² , more preferably about 0.0 to about 0.8 g / m 2. ² , more preferably about 0.1 to about 0.5 g / m ² , even more preferably about 0.1 to about 0.3 g / m ^{2 in} the basis weight range.

  This is because as the amount of the surfactant increases, menstrual blood tends to remain on the top sheet. The surfactant does not have a water retention value. This is because there is no layer of material to be measured because it is miscible with water.

The blood slipping agent-containing composition preferably contains water in an amount of about 0.0 to about 1.0 g / m ² , more preferably about 0.0 to about 0.8 g / m ² , and even more preferably about 0.00. 1 to about 0.5 g / m ² , and even more preferably about 0.1 to about 0.3 g / m ^{2 in} the basis weight range. Since water reduces the absorption performance of an absorbent article, it is preferable that water is small.

The blood slipping agent-containing composition, like the blood slipping agent, preferably has a kinematic viscosity at 40 ° C. of about 0 to about 80 mm ² / s, and about 1 to about 70 mm ^2. More preferably, it has a kinematic viscosity of about 3 to about 60 mm < ² > / s, even more preferably about 5 to about 50 mm < ² > / s, Even more preferably, it has a kinematic viscosity of from 7 to about 45 mm ² / s.

When the kinematic viscosity of the composition containing a blood slipperiness agent exceeds about 80 mm ² / s, the viscosity is high, and the blood slipperiness imparting composition is an absorbent article together with menstrual blood that has reached the skin contact surface of the top sheet. This is because it tends to be difficult to slide down inside.

  If the composition containing a blood slipperiness agent contains at least one other component that is miscible with the blood slipperiness agent, the other component preferably has a weight average molecular weight of less than about 1,000. More preferably having a weight average molecular weight of less than about 900. This is because if the weight average molecular weight is about 1,000 or more, the blood slipperiness-enhancing agent-containing composition itself has tackiness and tends to give the wearer discomfort. Moreover, since the viscosity of the composition containing a blood slipperiness-imparting agent tends to increase as the weight average molecular weight increases, the viscosity of the blood slipperiness-enhancing agent composition is lowered to a viscosity suitable for application by heating. As a result, the blood slipping agent may have to be diluted with a solvent.

  The composition containing a blood slipperiness imparting agent has a water retention of about 0.01 to about 4.0% by mass and a water retention of about 0.02 to about 3.5% by mass as the composition. Preferably about 0.03 to about 3.0 weight percent, more preferably about 0.04 to about 2.5 weight percent, and more preferably about 0.03 to about 3.0 weight percent More preferably, it has a water retention of 0.05 to about 2.0% by weight.

When the water retention rate is low, the affinity between the blood slipperiness-imparting agent composition and menstrual blood is reduced, and menstrual blood that has reached the skin contact surface of the top sheet is less likely to slide into the absorbent article. There is.
In addition, when a blood slipperiness | lubricity imparting agent containing composition contains a solid substance, it is preferable to remove them by filtration in the measurement of kinematic viscosity and a water retention.

Claims (13)

A liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent body provided between the top sheet and the back sheet, each having a transverse direction, a longitudinal direction, and a thickness direction orthogonal to each other. An absorbent article comprising:
The top sheet is a nonwoven fabric having a high fiber density region and a low fiber density region,
The absorbent body includes an absorbent core containing absorbent fibers, a topsheet side covering sheet that covers the topsheet side surface of the absorbent core, and a backsheet side that covers the backsheet side surface of the absorbent core A cover sheet, and a pressing recess formed by pressing the back sheet side cover sheet in the direction of the absorbent core,
The pressing recess has a low-pressure pressing recess formed in a mesh pattern, and a high-pressure pressing recess formed so as to be scattered in the mesh pattern,
When projecting the low fiber density region and the low-pressure squeezed recess on a virtual plane perpendicular to the thickness direction, the projection region of the low fiber density region has an overlap with the projection region of the low-squeeze recess. The absorbent article.   2. The absorbent article according to claim 1, wherein 2% or more of the projected area of the low fiber density area overlaps with the projected area of the low-pressure depression.   The absorptive article according to claim 1 or 2 whose fiber density of said low pressing recessed part is larger than the fiber density of said low fiber density field.   The absorbent article according to any one of claims 1 to 3, wherein a fiber density of the high-pressure recessed portion is larger than a fiber density of the high fiber density region.   The top sheet has a flange portion extending in the longitudinal direction and a groove portion extending in the longitudinal direction, the flange portion corresponds to the high fiber density region, and the groove portion is the low fiber. The absorbent article according to any one of claims 1 to 4, which corresponds to a density region. The low-pressure depression has an extending portion extending in the longitudinal direction;
The projection region of the groove portion has an overlap with the projection region of the extending portion when the groove portion and the low-pressure depression are projected on a virtual plane perpendicular to the thickness direction. Absorbent article.   The absorbent article according to claim 6, wherein 5% or more of the projection area of the groove portion overlaps with the projection area of the extending portion.   The absorbent article according to claim 6 or 7, wherein the projection area of the groove portion and the projection area of the extension portion overlap over the entire short direction of the projection area of the groove portion. The collar has a central portion located in the middle in the short direction, and both side portions located on both sides in the short direction with respect to the central portion,
The central portion has a fiber density lower than the average fiber density of the entire collar portion,
The absorbent article according to any one of claims 5 to 8, wherein the both side portions have a fiber density higher than an average fiber density of the entire collar portion. The absorbent body has a central portion located in the center in the longitudinal direction, and both side portions located on both sides in the longitudinal direction with respect to the central portion,
The absorptive article according to any one of claims 1 to 9, wherein the compressed concave portion is formed in the both side portions, but is not formed in the central portion.   The absorptive article according to any one of claims 1 to 10 in which said high pressing recessed part is formed in an intersection field of said network pattern. The top sheet side covering sheet is bonded to the top sheet side surface of the absorbent core by an adhesive,
The absorbent article according to any one of claims 1 to 11, wherein the backsheet-side covering sheet is bonded to the backsheet-side surface of the absorbent core with an adhesive. A blood slipping agent having a kinematic viscosity at 40 ° C. of 0.01 to 80 mm ² / s, a water retention of 0.01 to 4.0% by mass, and a weight average molecular weight of less than 1,000 on the top sheet. The absorbent article according to any one of claims 1 to 12, which is coated.

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