WO2013047866A1 - Absorbent Article - Google Patents

Abstract

An absorbent article includes a liquid-permeable top sheet(2A) provided on the skin facing side, a liquid- impermeable back sheet (3) provided on the non-skin facing side and a liquid-retaining absorbent body(4) provided between the top sheet(2A) and back sheet(3). At least a portion of at least the skin facing side surface of the top sheet(2A) is formed of a resin film having a lubricant layer(27A) formed on the skin facing side surface, and the lubricant layer(27A) is water-repellent and/or oil-repellent.

Description

DESCRIPTION

[TITLE OF THE INVENTION] Absorbent Article

Technical Field

[0001]

The present disclosure relates to an absorbent article.

Background Art

[0002]

Absorbent articles are known that employ polyolefin films as top sheets, having a plurality of openings formed therein for permeation of body fluids from a wearer (PTL 1, for example) . The body fluids from the wearer are absorbed into the absorbent body through the openings.

[Citation List]

[Patent Literature]

[0003]

[PTL 1] Japanese Patent Public Inspection No. 2006-515539

[0004]

In countries such as India, it is customary to use a single sanitary napkin for prolonged periods, by wiping off menstrual blood adhering onto the surface of the sanitary napkin with toilet paper or the like while in the toilet. With absorbent articles such as those described in PTL 1, however, a large amount of menstrual blood often remains on the surface of the top sheet even after menstrual blood adhering to the surface of the sanitary napkin has been wiped off with toilet paper or the like. When this occurs, the sanitary napkin appears filthy each time the sanitary napkin is viewed in the toilet, due to the menstrual blood remaining on the surface of the top sheet.

Summary

[0005]

Specifically, embodiments of the invention provide an absorbent article comprising a liquid-permeable top sheet provided on the skin facing side, a liquid- impermeable back sheet provided on the non-skin facing side and a liquid-retaining absorbent body provided between the top sheet and back sheet, wherein at least a portion of at least the skin facing side surface of the top sheet is formed of a resin film having a lubricant layer formed on the skin facing side surface, and the lubricant layer is water-repellent and/or oil-repellent. Brief Description of Drawings

[0006]

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

Fig. 2 is a schematic cross-sectional view showing a cross-section of the absorbent article of Fig. 1 along line A-A.

Fig. 3 is an illustration of the top sheet of an absorbent article according to the first embodiment of the invention.

Fig. 4 is an illustration of a method for producing the top sheet of an absorbent article according to the first embodiment of the invention.

Fig. 5 is set of illustrations of a recess-forming roll to be used in a method for producing the top sheet of an absorbent article according to the first embodiment of the invention.

Fig. 6 is a pair of illustrations of a stretching gear roll to be used in a method for producing the top sheet of an absorbent article according to the first embodiment of the invention.

Fig. 7 is an illustration of a resin film to be stretched by a stretching gear roll.

Fig. 8 is a set of illustrations showing the form of the resin film as it changes in each step of a method for producing the top sheet of an absorbent article according to the first embodiment of the invention.

Fig. 9 is a set of photomicrographs showing the top sheet of an absorbent article according to the first embodiment of the invention.

Fig. 10 is an illustration of the top sheet of an absorbent article according to a second embodiment of the invention.

Fig. 11 is an illustration of a method for producing the top sheet of an absorbent article according to the second embodiment of the invention.

Fig. 12 is an illustration of a composite sheet to be stretched by a stretching gear roll.

Fig. 13 is a set of photomicrographs of the skin facing side of a top sheet where openings have been formed in the resin film layer.

Fig. 14 is a pair of photomicrographs of the non- skin facing side of a top sheet where openings have been formed in the resin film layer.

Fig. 15 is an illustration of a modified example of the top sheet of an absorbent article according to at least one embodiment of the invention.

Fig. 16 is a pair of illustrations of a modified example of the top sheet of an absorbent article

according to at least one embodiment of the invention.

Fig. 17 is an illustration of a modified example of a top sheet according to at least one embodiment of the invention.

Fig. 18 is a set of photomicrographs taken of surfaces of examples and comparative examples.

Fig. 19 is a set of photographs showing the

condition of surfaces for examples and comparative examples, after dropping highly viscous artificial menstrual blood and allowing it to stand for 1 minute for examples and comparative examples.

Fig. 20 is a set of photographs showing the

condition of surfaces of toilet paper after wiping highly viscous artificial menstrual blood from examples and comparative examples.

Fig. 21 is a set of photographs showing the condition of surfaces of examples and comparative

examples after wiping highly viscous artificial menstrual blood using toilet paper.

Fig. 22 is an electron micrograph of the skin contact surface of a top sheet in a sanitary napkin wherein the top sheet comprises tri-C2L oil fatty acid glycerides .

Fig. 23 is a pair of photomicrographs of menstrual blood containing and not containing a blood modifying agent.

Fig. 24 is a diagram illustrating a method of measuring surface tension.

DESCRIPTION OF EMBODIMENTS

[0007]

- First embodiment -

An absorbent article according to the first

embodiment of the invention will now be described with reference to the accompanying drawings, with the

understanding that the invention is not limited to the examples depicted in the drawings.

Fig. 1 is partial cutaway plan view showing an absorbent article according to the first embodiment of the invention, and Fig. 2 is a schematic cross-sectional view showing a cross-section of the absorbent article of Fig. 1 along line A-A. The absorbent article 1 comprises a liquid-permeable top sheet 2A provided on the skin facing side, a liquid-impermeable back sheet 3 provided on the non-skin facing side, and a liquid-retaining absorbent body 4 provided between the top sheet 2A and back sheet 3. In this embodiment, the back sheet 3 extends outwardly in the widthwise direction to form a pair of wing sections 5 and an attachment part 6 is provided on the non-skin facing side of the wing section 5. In Fig. 1, the widthwise direction of the absorbent article 1 is the X-direction, and the lengthwise

direction is the Y-direction. The planar direction of the absorbent article 1 is the XY direction. [0008]

The top sheet 2A transports body fluid such as urine and menstrual blood that has been excreted from a wearer into the absorbent body 4. At least a portion of the top sheet 2A is liquid-permeable and the top sheet 2A is formed for example of a resin film that has numerous openings formed for permeation of body fluid. The resin film used as the top sheet 2A may comprise a copolymer of an olefin and another monomer such as an acrylic acid ester or vinyl acetate, or a polyolefin, polyester, polypropylene, polyethylene, polyethylene terephthalate, polyamide, cellulose acetate or the like. For high softness and reduced irritation to the skin, the resin film to be used as the top sheet 2 is most preferably a copolymer of an olefin and another monomer, or a

polyolefin.

[0009]

The basis weight of the top sheet 2A is preferably at least 1 g/m² and no greater than 40 g/m², and more preferably at least 10 g/m² and no greater than 35 g/m².

Also, the thickness of the top sheet 2A is preferably at least 0.01 mm and no greater than 0.4 mm, and more preferably at least 0.1 mm and no greater than 0.35 mm. If the thickness of the top sheet 2A is less than 0.01 mm, the concealing property of the top sheet 2A,

described hereunder, may be too low, while if the

thickness of the top sheet 2A exceeds 0.4 mm, the

stiffness of the top sheet 2A may be increased and irritation by the top sheet 2A on the skin of the wearer may be too strong.

[0010]

The top sheet 2A preferably has a concealing

property so that body fluids absorbed into the absorbent body 4 cannot be seen from the exterior. The concealing property of the top sheet 2A may be produced for example by mixing a filler such as titanium oxide in a resin. When the filler is titanium oxide, the titanium oxide content is preferably at least 1% and no greater than 50%, and more preferably at least 3% and no greater than 15%, with respect to the weight of the resin film. If the titanium oxide content is less than 1% with respect to the weight of the resin film, the concealing effect of the top sheet 2A for body fluids absorbed into the absorbent body 4 may be too small. If the titanium oxide content exceeds 50% of the weight of the resin film, it may become difficult to form a sheet from the titanium oxide-containing resin.

[0011]

The top sheet 2A is formed in such that the

widthwise cross-section is essentially undulating, in order to reduce the contact area between the skin of the wearer and the top sheet 2A and obtain satisfactory feel on the skin for the top sheet 2A. The top sheet 2A may also be formed such that the cross-section is essentially undulating in the lengthwise direction. The top sheet 2A may also be formed such that the cross-section is

essentially undulating. This will allow the top sheet 2A to be flattened as the essentially undulating shape of the top sheet 2A is deformed by pressure applied to the surface of the top sheet 2A when body fluid such as menstrual blood is wiped off by the wearer using toilet paper or the like, thereby facilitating the act of wiping off body fluid that has adhered onto the surface of the top sheet 2A.

[0012]

The top sheet 2A will now be explained in greater detail with reference to Fig. 3.

The top sheet 2A formed such that the widthwise cross-section is essentially undulating, in this

embodiment, has protrusions 21A extending in the

lengthwise direction and bottom sections 22A arranged between adjacent protrusions 21A. The direction in which the protrusions 21A extend is not limited to the

lengthwise direction. The protrusions 21A each has a top section 23A that contacts with the skin of the wearer, and wall sections 24A on the sides. The height of the protrusions 21A in the thickness direction, i.e. the difference in height between the top sections 23A and bottom sections 22A in the thickness direction, is preferably at least 0.1 mm and no greater than 5 mm. If the difference in height between the top sections 23A and bottom sections 22A in the thickness direction is less than 0.1 mm, body fluid that has been absorbed into the absorbent body 4 may flow back through the openings 25A of the top sheet 2, which are described hereunder. If the difference in height between the top sections 23A and bottom sections 22A in the thickness direction is greater than 5 mm, the protrusions 21A may collapse when the absorbent article 1 is worn by the wearer.

[0013]

The wall sections 24A are preferably slanted instead of perpendicular with respect to the bottom sections 22A. That is, the angle formed between the bottom sections 22A and wall sections 24A is preferably greater than 90°.

However, the angle formed between the bottom sections 22A and wall sections 24A is also preferably no greater than 165°. Forming an angle between the bottom sections 22A and wall sections 24A of 90° or smaller requires a large degree of plastic deformation of the resin film, and therefore the strength of the top sheet 2A can be

severely weakened when the angle formed between the bottom sections 22A and wall sections 24A is 90° or smaller. If the angle formed between the bottom sections 22A and wall sections 24A is greater than 165°, body fluid that has been absorbed into the absorbent body 4 may flow back through the openings 25A in the top sheet 2A, which are described hereunder, or body fluid that has been absorbed into the absorbent body 4 through the openings 25A may become visible, thus reducing the concealing property of the top sheet 2A. [0014]

The wall sections 24A of the top sheet 2A have a plurality of openings 25A arranged in the direction of the protrusions, i.e., the direction extending along each of the protrusions 21A (lengthwise direction) . The .

openings 25A are holes passing through the top sheet 2A, and body fluid of the wearer is absorbed into the

absorbent body 4 through the openings 25A. The open area of each opening 25A is preferably at least 0.001 mm² and no greater than 1 mm², and more preferably at least 0.01 mm² and no greater than 0.1 mm². If the open area of each opening 25A is smaller than 0.001 mm², body fluid of the wearer may not pass through the openings 25A, and if the open area of each opening 25A is greater than 1 mm², body fluid that has been absorbed into the absorbent body 4 may flow back through the openings 25A of the top sheet 2A, or body fluid that has been absorbed into the

absorbent body 4 may become visible through the openings 25A, thus reducing the concealing property of the top sheet 2A.

[0015]

The proportion of the total open area of all

openings 25A with respect to the entire area of the top sheet 2A, i.e., the open area ratio of the top sheet 2A, is preferably at least 5% and no greater than 20%. If the open area ratio of the top sheet 2A is lower than 5%, permeability of the body fluid in the top sheet 2A may be poor, and if the open area ratio of the top sheet 2A is greater than 20%, body fluid that has been absorbed into the absorbent body 4 may flow back through the openings

25A of the top sheet 2A, or body fluid that has been absorbed into the absorbent body 4 may become visible through the openings 25A, thus reducing the concealing property of the top sheet 2A.

[0016]

The openings 25A are formed from the vicinity of the top sections 23A to the vicinity of the bottom sections 22A. Thus, even when a large amount of body fluid has been excreted at one time by the wearer, the absorbent article 1 can absorb the body fluid and thus prevent leakage of the body fluid from the absorbent article 1.

[0017]

The top sections 23A of the top sheet 2A in this embodiment each have a plurality of recesses 26A arranged in the direction extending along each of the protrusions 21A (lengthwise direction) . The shapes of the recesses 26A in the planar direction may be rhomboid, for example, with rhomboid side lengths of 0.15 mm, for example, and a center-to-center distance between adjacent recesses of 0.34 mm, for example. The shapes of the recesses 26A in the planar direction are not limited to being rhomboid, and may instead be square, rectangular, triangular, circular, star-shaped, linear (straight linear) or the like. Also, the sizes of the recesses 26A are not limited to 0.15 mm x 0.15 mm, and the center-to-center distance between adjacent recesses is not limited to 0.34 mm. The depths of the recesses 26A are not particularly restricted so long as they are depths such that the skin of the wearer does not contact the bottoms of the

recesses 26A when the skin of the wearer has contacted the top sections 23A of the top sheet 2A. The bottom sections 22A of the top sheet 2A may also have a

plurality of recesses 26A arranged in the direction extending along each of the protrusions 21A (the

lengthwise direction), but they may be omitted.

[0018]

The recesses 26A formed on the top sections 23A reduce the contact area of the top sections 23A that directly contacts with the skin of the wearer, and this reduces sticking of the absorbent article 1 onto the skin during wearing, and minimizes discomfort and itching of the wearer or skin trouble such as eruptions by the wearer. The lubricant described hereunder may also be contained in the recesses 26A. As a result, the lubricant will remain in the recesses 26A even after body fluid such as menstrual blood adhering to the top sheet 2A has been wiped off with toilet paper or the like, and the lubricant remaining in the recesses 26A will spread on the surface of the top sheet 2A, thus allowing

replenishment of the lubricant to the lubricant layer

27A.

[0019]

A lubricant is coated on the surface of the top sheet 2A to form a lubricant layer 27A on the skin facing side surface of the top sheet 2A. With the lubricant layer 27A, it is possible to obtain low residue of body fluid, or no residue of body fluid, after body fluid such as menstrual blood adhering to the top sheet 2A has been wiped off with toilet paper or the like. The lubricant layer 27A may be formed over the entire top sheet 2A, or the lubricant layer 27A may be formed on the top sheet 2A only at the regions corresponding to the areas of the absorbent article 1 where body fluid of the wearer will be excreted. Specifically, the lubricant layer 27A may be formed on at least a portion of the surface of the top sheet 2A.

[0020]

The lubricant layer 27A is water-repellent and/or oil-repellent. The lubricant of the lubricant layer 27A is not particularly restricted so long as it is a

compound that can impart a water-repellent and/or oil- repellent property to the top sheet 2A, and it is

preferably a fluorinated compound, silicon compound or blood modifying agent. The lubricant of the lubricant layer 27A is more preferably a blood modifying agent. The blood modifying agent has an Inorganic-Organic

Balance of 0.00-0.60, a melting point of no higher than 45°C, and a water solubility of no greater than 0.05 g at 25°C in lOOg of water.

[0021]

Since the melting point of the blood modifying agent is no higher than 45°C, the blood modifying agent becomes liquefied upon contact with body fluid at 30°C to 40°C, even if the blood modifying agent is a solid. Since the liquid blood modifying agent is present between the body fluid and the top sheet 2A, it makes it possible to obtain low residue of body fluid, or no residue of body fluid, after body fluid adhering to the top sheet 2A has been wiped off with toilet paper or the like.

[0022]

The blood modifying agent has a mechanism of lowering the viscosity and surface tension of blood.

This will allow highly viscous body fluid that has adhered onto the top sheet 2A to be easily wiped off, since the viscosity and surface tension of the adhered body fluid are reduced.

[0023]

The IOB (Inorganic Organic Balance) is an indicator of the hydrophilic-lipophilic balance, and as used herein, it is the value calculated by the following formula by Oda et al.:

IOB = inorganic value/organic value.

[0024]

The inorganic value and the organic value are based on the organic paradigm described in "Organic compound predictions and organic paradigms" by Fujita A., Kagaku no Ryoiki (Journal of Japanese Chemistry), Vol.11, No.10 (1957) p.719-725 which is incorporated by reference herein.

The organic values and inorganic values of major groups, according to Fujita, are summarized in Table 1 below.

[0025] Table 1

[0026]

For example, in the case of an ester of

tetradecanoic acid which has 14 carbon atoms and dodecyl alcohol which has 12 carbon atoms, the organic value is 520 (CH₂, 20 x 26) and the inorganic value is 60 (-COOR,

60 x 1), and therefore IOB = 0.12.

[0027]

In the blood modifying agent, the IOB is about 0.00- 0.60, preferably about 0.00-0.50, more preferably about 0.00-0.40 and even more preferably about 0.00-0.30. This is because a lower IOB is associated with higher

organicity and higher affinity with blood cells.

[0028]

As used herein, the term "melting point" refers to the peak top temperature for the endothermic peak during conversion from solid to liquid, upon measurement with a differential scanning calorimetry analyzer at a

temperature-elevating rate of 10°C/min. The melting point may be measured using a Model DSC-60 DSC measuring apparatus by Shimadzu Corp., for example.

[0029] If the blood modifying agent has a melting point of no higher than about 45°C, it may be either liquid or solid at room temperature, or in other words, the melting point may be either about 25°C or higher or below about 25°C, and for example, it may have a melting point of about -5°C or about -20°C. The reason for a melting point of no higher than about 45°C for the blood modifying agent will be explained below.

[0030]

The blood modifying agent does not have a lower limit for the melting point, but the vapor pressure is preferably low. The vapor pressure of the blood

modifying agent is preferably about 0.00-0.01 Pa, more preferably about 0.000-0.001 Pa and even more preferably about 0.0000-0.0001 Pa, at 1 atmosphere, 25°C.

Considering that the absorbent article of this disclosure is to be used in contact with the human body, the vapor pressure is preferably about 0.00-0.01 Pa, more

preferably about 0.000-0.001 Pa and even more preferably about 0.0000-0.0001 Pa, at 1 atmosphere, 40°C. If the vapor pressure is high, gasification may occur during storage and the amount of blood modifying agent may be reduced, and may create problems such as odor during wear .

[0031]

The melting point of the blood modifying agent may also differ depending on the weather or duration of wear. For example, in regions with a mean atmospheric

temperature of no higher than about 10°C, using a blood modifying agent with a melting point of no higher than about 10°C may allow the blood modifying agent to stably modify blood after excretion of menstrual blood, even if it has been cooled by the ambient temperature.

Also, when the absorbent article is used for a prolonged period of time, the melting point of the blood modifying agent is preferably at the high end of the range of no higher than about 45°C. This is because the blood modifying agent is not easily affected by sweat or friction during wearing, and will not easily migrate even during prolonged wearing.

[0032]

The water solubility of 0.00-0.05 g may be measured by adding 0.05 g of sample to 100 g of deionized water at 25°C, allowing it to stand for 24 hours, and after 24 hours, gently stirring if necessary, and then visually evaluating whether or not the sample has dissolved.

As used herein, the term "solubility" in regard to water solubility includes cases where the sample

completely dissolves in deionized water to form a

homogeneous mixture, and cases where the sample is completely emulsified. As used herein, "completely" means that no mass of the sample remains in the deionized water .

[0033]

When top sheet surfaces are coated with surfactants in order to alter the surface tension of blood and promote the rapid absorption of blood, because

surfactants generally have high water solubility, the surfactant-coated top sheet is highly miscible with hydrophilic components (such as blood plasma) in the blood and therefore, instead, blood residue tends to remain on the top sheet. The aforementioned blood modifying agent has low water solubility, and therefore, blood residue does not remain on the top sheet and allows rapid migration into the absorbent body.

[0034]

As used herein, a water solubility of water at 25°C may be simply referred to as "water solubility".

[0035]

As used herein, "weight-average molecular weight" includes the concept of a polydisperse compound (for example, a compound produced by stepwise polymerization, an ester formed from a plurality of fatty acids and a , plurality of aliphatic monohydric alcohols) , and a simple compound (for example, an ester formed from one fatty acid and one aliphatic monohydric alcohol) , and in a system comprising _± molecules with molecular weight Mi (i

= 1, or i = 1, 2 . . . ), it refers to M_w determined by the following formula.

M_w = ∑ΝιΜι²/∑Ν_ίΜ_ί

[0036]

As used herein, the weight-average molecular weights are the values measured by gel permeation chromatography (GPC) , based on polystyrene.

The GPC measuring conditions may be the following, for example.

Device: Lachrom Elite high-speed liquid chromatogram by Hitachi High-Technologies Corp.

Columns: SHODEX KF-801, KF-803 and KF-804, by Showa Denko K.K.

Eluent: THF

Flow rate: 1.0 mL/min

Driving volume: 100 μΐ,

Detection: RI (differential refractometer)

The weight-average molecular weights listed in the examples of the present specification were measured under the conditions described below.

[0037]

Preferably, the blood modifying agents is selected from the group consisting of the following items (i)- (iii) , and any combination thereof:

(i) a hydrocarbon;

(ii) a compound having (ii-1) a hydrocarbon moiety, and (ii-2) one or more groups each selected from the group consisting of carbonyl group (-CO-) and oxy group (-0-) inserted between a C-C single bond of the

hydrocarbon moiety; and

(iii) a compound having (iii-1) a hydrocarbon moiety, (iii-2) one or more groups each selected from the group consisting of carbonyl group (-CO-) and oxy group (-0-) inserted between a C-C single bond of the

hydrocarbon moiety, and (iii-3) one or more groups each selected from the group consisting of carboxyl group (- COOH) and hydroxyl group (-OH) substituting a hydrogen of the hydrocarbon moiety.

[0038]

As used herein, "hydrocarbon" refers to a compound composed of carbon and hydrogen, and it may be a chain hydrocarbon, such as a paraffinic hydrocarbon (containing no double bond or triple bond, also referred to as alkane) , an olefin-based hydrocarbon (containing one double bond, also referred to as alkene) , an acetylene- based hydrocarbon (containing one triple bond, also referred to as alkyne) , or a hydrocarbon comprising two or more bonds each selected from the group consisting of double bonds and triple bonds, and cyclic hydrocarbon, such as aromatic hydrocarbons and alxcyclic hydrocarbons.

[0039]

Preferred as such hydrocarbons are chain

hydrocarbons and alicyclic hydrocarbons, with chain hydrocarbons being more preferred, paraffinic

hydrocarbons, olefin-based hydrocarbons and hydrocarbons with two or more double bonds (containing no triple bond) being more preferred, and paraffinic hydrocarbons being even more preferred.

Chain hydrocarbons include linear hydrocarbons and branched hydrocarbons.

[0040]

When two or more oxy group (-0-) are inserted in the compounds of (ii) and (iii) above, the oxy group (-0-) are not adjacent to each other. Thus, compounds (ii) and (iii) do not include compounds with continuous oxy group (i.e., peroxides) .

[0041]

In the compounds of (iii) , compounds in which at least one hydrogen on the hydrocarbon moiety is substituted with a hydroxyl group (-OH) are more

preferred than compounds in which at least one hydrogen on the hydrocarbon moiety is substituted with a carboxyl group (-COOH) . As shown in Table 1, the carboxyl groups bond with metals and the like in menstrual blood,

drastically increasing the inorganic value from 150 to 400 or greater, and therefore a blood modifying agent with carboxyl groups can increase the IOB value to more than about 0.6 during use, potentially lowering the affinity with blood cells.

[0042]

More preferably, the blood modifying agent is a compound selected from the group consisting of the following items (i')-(iii'), and any combination thereof:

(i') a hydrocarbon;

(ii¹) a compound having at least (ii'-l) a

hydrocarbon moiety, and (ii'-2) one or more bonds each selected from the group consisting of carbonyl bond (-CO- ), at least one ester bond (-C00-) , at least one

carbonate bond (-OCOO-) , and/or at least one ether bond

(-0-) inserted between a C-C single bond of the

hydrocarbon moiety; and

(iii¹) a compound having at least one(iii'-l) a hydrocarbon moiety, (iii '-2) one or more bonds each selected from the group consisting of carbonyl bond (-CO-

) , at least one ester bond (-C00-) , at least one

carbonate bond (-OCOO-) , and/or at least one ether bond (-0-) inserted between a C-C single bond of a

hydrocarbon, and (iii '-3) one or more groups each

selected from the group consisting of carboxyl group (-

COOH) or/and hydroxyl group (-OH) substituting a hydrogen on the hydrocarbon moiety.

[0043]

When 2 or more of the same or different bonds are inserted in the compound of (ii¹) or (iii')_/ i.e., when 2 or more bonds each selected from the group consisting of carbonyl bonds (-CO-) , ester bonds (-C00-) , carbonate bonds (-0C00-) and ether bonds (-0-) are inserted, the bonds are not adjacent to each other, and at least one carbon atom lies between each of the bonds.

[0044]

The blood modifying agent is more preferably a compound with no more than about 1.8 carbonyl bonds (-CO- ), no more than 2 ester bonds (-C00-), no more than about 1.5 carbonate bonds (-0C00-) , no more than about 6 ether bonds (-0-), no more than about 0.8 carboxyl groups (- COOH) and/or no more than about 1.2 hydroxyl groups (- OH) , per 10 carbon atoms in the hydrocarbon moiety.

[0045]

Even more preferably, the blood modifying agent is selected from the group consisting of the following items (A) -(F), and any combination thereof:

(A) an ester of (Al) a compound having a chain hydrocarbon moiety and 2-4 hydroxyl groups substituting hydrogens on the chain hydrocarbon moiety, and (A2) a compound having a chain hydrocarbon moiety and 1 carboxyl group,

substituting a hydrogen on the chain hydrocarbon moiety;

(B) an ether of (Bl) a compound having a chain hydrocarbon moiety and 2-4 hydroxyl groups substituting hydrogens on the chain hydrocarbon moiety and (B2) a compound having a chain hydrocarbon moiety and 1 hydroxyl group, substituting a hydrogen on the chain hydrocarbon moiety;

(C) an ester of (CI) a carboxylic acid, hydroxy acid, alkoxy acid or oxoacid comprising a chain

hydrocarbon moiety and 2-4 carboxyl groups substituting hydrogens on the chain hydrocarbon moiety and (C2) a compound having a chain hydrocarbon moiety and 1 hydroxyl group substituting a hydrogen on the chain hydrocarbon moiety;

(D) a compound having a chain hydrocarbon moiety and one bond selected from the group consisting of ether bond (-0-), carbonyl bond (-CO-), ester bond (-C00-) and carbonate bond (-OCOO-) inserted in-between a C-C single bond of the chain hydrocarbon moiety;

(E) a polyoxy C₂-6 alkylene glycol, or alkyl ester or alkyl ether thereof; and

(F) a chain hydrocarbon.

The blood modifying agent in accordance with (A) to (F) will now be described in detail.

[0046]

[ (A) Ester of (Al) a compound having a chain hydrocarbon moiety and 2-4 hydroxyl groups substituting hydrogens on the chain hydrocarbon moiety, and (A2) a compound having a chain hydrocarbon moiety and 1 carboxyl group

substituting a hydrogen on the chain hydrocarbon moiety] The (A) ester of (Al) a compound having a chain hydrocarbon moiety and 2-4 hydroxyl groups substituting hydrogens on the chain hydrocarbon moiety, and (A2) a compound having a chain hydrocarbon moiety and 1 carboxyl group substituting a hydrogen on the chain hydrocarbon moiety (hereunder also referred to as "compound (A)") includes esters of a compound with 4, 3 or 2 hydroxyl groups and a compound with 1 carboxyl group, and it is not necessary for all of the hydroxyl groups to be esterified so long as the IOB, melting point and water solubility are within the aforementioned ranges.

[0047]

Examples of (Al) a compound having a chain

hydrocarbon moiety and 2-4 hydroxyl groups substituting hydrogens on the chain hydrocarbon moiety (hereunder also referred to as "compound (Al)") include chain hydrocarbon tetraols such as alkanetetraols, including

pentaerythritol, chain hydrocarbon triols such as

alkanetriols , including glycerins, and chain hydrocarbon diols such as alkanediols, including glycols. Examples of (A2) a compound having a chain hydrocarbon moiety and 1 carboxyl group substituting a hydrogen on the chain hydrocarbon moiety (hereunder also referred to as

"compound (A2)") include compounds in which one hydrogen on the hydrocarbon is substituted with one carboxyl group

(-COOH) , such as fatty acids.

Examples for compound (A) include (ai) an ester of a chain hydrocarbon tetraol and at least one fatty acid,

(a₂) an ester of a chain hydrocarbon triol and at least one fatty acid, and (a₃) an ester of a chain hydrocarbon diol and at least one fatty acids.

[0048]

[ (ai) Ester of a chain hydrocarbon tetraol and at least one fatty acid]

Examples of an ester of a chain hydrocarbon tetraol and at least one fatty acid include tetraesters of pentaerythritol and fatty acids, represented by the following formula (1) :

triesters of pentaerythritol and fatty acids, represented by the following formula (2) :

diesters of pentaerythritol and fatty acids, represented by the following formula (3) :

and monoesters of pentaerythritol and fatty acids, represented by the following formula (4) .

In the formulae, F^-R each represent a chain

hydrocarbon .

[0049]

The fatty acids composing the esters of

pentaerythritol and fatty acids (F^COOH, R²COOH, R³COOH, and R⁴COOH) are not particularly restricted as long as the pentaerythritol and fatty acid esters satisfy the

conditions for the IOB, melting point and water

solubility, and for example, there may be mentioned saturated fatty acids, such as C2-C30 saturated fatty acids, including acetic acid (C₂) (C₂ representing the number of carbons, corresponding to the number of carbons of each of B C , R²C, R³C or R⁴C, same hereunder) , propanoic acid (C₃) , butanoic acid (C₄) and isomers thereof such as 2-methylpropanoic acid (C₄) , pentanoic acid (C₅) and isomers thereof such as 2-methylbutanoic acid (C₅) and 2 , 2-dimethylpropanoic acid (C₅) , hexanoic acid ( e) , heptanoic acid (C₇) , octanoic acid (C₈) and isomers thereof, such as 2-ethylhexanoic acid (C₈) , nonanoic acid (Cg) , decanoic acid (C10) , dodecanoic acid (C12) ,

tetradecanoic acid (C14) , hexadecanoic acid (Ci₆) ,

heptadecanoic acid (C17) , octadecanoic acid (Ci₈) ,

eicosanoic acid (C₂o) , docosanoic acid (C22) , tetracosanoic acid (C₂₄) , hexacosanoic acid (C₂6) , octacosanoic acid (C₂8) and triacontanoic acid (C₃₀) , as well as isomers of the foregoing (excluding those mentioned above) .

[0050]

The fatty acid may also be an unsaturated fatty acid. Examples of unsaturated fatty acids include C3-C20 unsaturated fatty acids, such as monounsaturated fatty acids including crotonic acid (C₄) , myristoleic acid (C14) , palmitoleic acid (Ci6) , oleic acid (Cis) , elaidic acid (Cis) , vaccenic acid (Cia) , gadoleic acid (C₂o) and eicosenoic acid ( C20 ) _/ di-unsaturated fatty acids

including linolic acid (Ci₈) and eicosadienoic acid ( C20 ) , tri-unsaturated fatty acids including linolenic acids, such as cc-linolenic acid (Ci₈) and γ-linolenic acid (Ci₈) , pinolenic acid {C₁₈) , eleostearic acids, such as a- eleostearic acid (Ci₈) and β-eleostearic acid (Ci₈) , Mead acid ( C20 ) dihomo-y-linolenic acid (C₂o) and

eicosatrienoic acid ( C20 ) , tetra-unsaturated fatty acids including stearidonic acid (C₂o) , arachidonic acid ( C20 ) and eicosatetraenoic acid ( C20 ) _/ penta-unsaturated fatty acids including bosseopentaenoic acid (Cis) and

eicosapentaenoic acid ( C20 ) , and partial hydrogen adducts of the foregoing.

[0051]

Considering the potential for degradation by

oxidation and the like, the ester of pentaerythritol and a fatty acid is preferably an ester of pentaerythritol and a fatty acid, which is derived from a saturated fatty acid, i.e., an ester of pentaerythritol and a saturated fatty acid.

Also, in order to lower the IOB and result in greater hydrophobicity, the ester of pentaerythritol and a fatty acid is preferably a diester, triester or

tetraester, more preferably a triester or tetraester, and even more preferably a tetraester.

[0052]

In a tetraester of pentaerythritol and a fatty acid, the IOB is 0.60 if the total number of carbons of the fatty acid composing the tetraester of the

pentaerythritol and fatty acid, i.e., the total number of carbons of the R¹C, R²C, R³C and R C portions in formula (1), is 15. Thus, when the total number of carbons of the fatty acid composing the tetraester of the

pentaerythritol and fatty acid is approximately 15 or greater, the IOB satisfies the condition of being within about 0.00 to 0.60.

Examples of tetraesters of pentaerythritol and fatty acids include tetraesters of pentaerythritol with

hexanoic acid ( e) , heptanoic acid (C₇) , octanoic acid (Ce) such as 2-ethylhexanoic acid (Ce) , nonanoic acid (C₉) , decanoic acid (Ci₀) and/or dodecanoic acid (Ci₂) .

[0053]

In a triester of pentaerythritol and a fatty acid, the IOB is 0.58 if the total number of carbons of the fatty acid composing the triester of the pentaerythritol and fatty acid, i.e., the total number of carbons of the i^C, R²C and R³C portions in formula (2), is 19. Thus, when the total number of carbons of the fatty acid composing the triester of the pentaerythritol and fatty acid is approximately 19 or greater, the IOB satisfies the condition of being within about 0.00 to 0.60.

[0054]

In a diester of pentaerythritol and a fatty acid, the IOB is 0.59 if the total number of carbons of the fatty acid composing the diester of the pentaerythritol and fatty acid, i.e., the total number of carbons of the

R^XC or R²C portion in formula (3), is 22. Thus, when the total number of carbons of the fatty acid composing the diester of the pentaerythritol and fatty acid is

approximately 22 or greater, the IOB satisfies the condition of being within about 0.00 to 0.60.

[0055]

In a monoester of pentaerythritol and a fatty acid, the IOB is 0.60 if the total number of carbons of the fatty acid composing the monoester of the pentaerythritol and fatty acid, i.e., the total number of carbons of the

R^C portion in formula (4), is 25. Thus, when the number of carbons of the fatty acid composing the monoester of the pentaerythritol and fatty acid is approximately 25 or greater, the IOB satisfies the condition of being within about 0.00 to 0.60.

The effects of double bonds, triple bonds, iso- branches and tert-branches are not considered in this calculation .

[0056]

Commercial products which are esters of

pentaerythritol and fatty acids include UNISTAR H-408BRS and H-2408BRS-22 (mixed product) (both products of NOF

Corp . ) .

[0057]

[ (a₂) Ester of a chain hydrocarbon triol and at least one fatty acid]

Examples of esters of a chain hydrocarbon triol and at least one fatty acid include triesters of glycerin and fatty acids, represented by formula (5) :

CH₂OOCR⁵

CHOOCR⁶ (5)

I

CH₂OOCR⁷ diesters of glycerin and fatty acids, represented by the following formula (6):

CH₂OOCR⁵ CH₂OOCR⁵

I I

CHOH or CHOOCR⁶ (6)

I I CH₂OOCR⁶ CH₂OH

and monoesters of glycerin and fatty acids, represented by the following formula (7):

CH₂OOCR⁵ CH₂OH

I I

CHOH or CHOOCR⁵ (7)

I I CH₂OH CH₂OH

wherein R⁵-R⁷ each represent a chain hydrocarbon.

[0058]

The fatty acid composing the ester of glycerin and a fatty acid (RCOOH, R⁶COOH and R⁷COOH) is not particularly restricted as long as the ester of glycerin and a fatty acid satisfies the conditions for the IOB, melting point and water solubility, and for example, there may be mentioned that the fatty acids mentioned for the " (ai)

Ester of chain hydrocarbon tetraol and at least one fatty acids", namely saturated fatty acids and unsaturated fatty acids, and in consideration of the potential for degradation by oxidation and the like, the ester is preferably a glycerin and fatty acid ester, which is derived from a saturated fatty acid, i.e., an ester of glycerin and a saturated fatty acid.

Also, in order to lower the IOB and result in greater hydrophobicity, the ester of glycerin and a fatty acid is preferably a diester or triester, and more preferably a triester.

[0059]

A triester of glycerin and a fatty acid is also known as a triglyceride, and examples include triesters of glycerin and octanoic acid (Cs) , triesters of glycerin and decanoic acid (Ci₀) , triesters of glycerin and

dodecanoic acid (Ci₂) , triesters of glycerin and 2 or more different fatty acids, and mixtures of the foregoing.

[0060]

Examples of triesters of glycerin and 2 or more fatty acids include triesters of glycerin with octanoic acid (Cs) and decanoic acid (Cio) , triesters of glycerin with octanoic acid (C_g) , decanoic acid (Cio) and

dodecanoic acid (C_i2) , and triesters of glycerin with octanoic acid (C₈) , decanoic acid (Ci₀) , dodecanoic acid

(C12) , tetradecanoic acid (Ci₄) , hexadecanoic acid (Ci6) and octadecanoic acid (Cis) .

[0061]

In order to obtain a melting point of no higher than about 45°C, preferred triesters of glycerin and fatty acids are those with no more than about 40 as the total number of carbons of the fatty acid composing the triester of glycerin and the fatty acid, i.e., the total number of carbons of the RC, R⁶C and R⁷C portions in formula (5) .

[0062]

In a triester of glycerin and a fatty acid, the IOB value is 0.60 when the total number of carbons of the fatty acid composing the triester of glycerin and the fatty acid, i.e., the total number of carbons of the RC, R⁶C and R⁷C portions in formula (5), is 12. Thus, when the total number of carbons of the fatty acid comprising the triester of the glycerin and fatty acid is

approximately 12 or greater, the IOB satisfies the condition of being within about 0.00 to 0.60.

Triesters of glycerin and fatty acids, being

aliphatic and therefore potential constituent components of the human body are preferred from the viewpoint of safety.

[0063]

Commercial products of triesters of glycerin and fatty acids include tri-coconut fatty acid glycerides,

NA36, PANACET 800, PANACET 800B and PANACET 81OS, and tri-C2L oil fatty acid glycerides and tri-CL oil fatty acid glycerides (all products of NOF Corp.).

[0064]

A diester of glycerin and a fatty acid is also known as a diglyceride, and examples include diesters of glycerin and decanoic acid (C₁₀) , diesters of glycerin and dodecanoic acid (C12) , diesters of glycerin and

hexadecanoic acid (Ci₆) , diesters of glycerin and 2 or more different fatty acids, and mixtures of the

foregoing .

In a diester of glycerin and a fatty acid, the IOB is 0.58 if the total number of carbons of the fatty acid composing the diester of the glycerin and fatty acid, i.e., the total number of carbons of the R⁵C and R⁶C portions in formula (6), is 16. Thus, when the total number of carbons of the fatty acid composing the diester of the glycerin and fatty acid is approximately 16 or greater, the IOB satisfies the condition of being about

0.00 to 0.60.

[0065]

Monoesters of glycerin and fatty acids are also known as monoglycerides, and examples include glycerin and icosanoic acid (C₂o) monoester, and glycerin and docosanoic acid (C22) monoester.

In a monoester of glycerin and a fatty acid, the IOB is 0.59 if the number of carbons of the fatty acid composing the monoester of the glycerin and fatty acid,

1. e., the number of carbons of the R⁵C portion in formula (7), is 19. Thus, when the number of carbons of the fatty acid composing the monoester of the glycerin and fatty acid is approximately 19 or greater, the IOB satisfies the condition of being about 0.00 to 0.60.

[0066]

[ (a₃) Ester of chain hydrocarbon diol and at least one fatty acid]

Examples of an ester of a chain hydrocarbon diol and at least one fatty acid include monoesters and diesters of fatty acids with C₂-C6 chain hydrocarbon diols, such as C2^_C₆ glycols, including ethylene glycol, propylene glycol, butylene glycol, pentylene glycol and hexylene glycol.

[0067]

Specifically, examples of an ester of a chain hydrocarbon diol and at least one fatty acid include diesters of C₂-C6 glycols and fatty acids, represented by the following formula (8) :

R⁸COOC_kH_2kOCOR⁹ (8)

wherein k represents an integer of 2-6, and R⁸ and R⁹ each represent a chain hydrocarbon,

and monoesters of C₂-C6 glycols and fatty acids,

represented by the following formula (9):

R⁸COOC_kH_2kOH (9)

wherein k represents an integer of 2-6, and R⁸ is a chain hydrocarbon.

[0068]

The fatty acid to be esterified in an ester of a C₂- C₆ glycol and a fatty acid (corresponding to R⁸COOH and R⁹COOH in formula (8) and formula (9)) is not particularly restricted as long as the ester of the C₂-C₆ glycol and fatty acid satisfies the conditions for the IOB, melting point and water solubility, and for example, there may be mentioned that the fatty acids mentioned for the " (ai) Ester of a chain hydrocarbon tetraol and at least one fatty acid", namely saturated fatty acids and unsaturated fatty acids, and in consideration of the potential for degradation by oxidation and the like, it is preferably a saturated fatty acid.

[0069]

In a diester of butylene glycol (k = 4) and a fatty acid represented by formula (8), IOB is 0.60 when the total number of carbons of the R⁸C and R⁹C portions is 6. Thus, when the total number of carbon atoms in a diester of butylene glycol (k = 4) and a fatty acid represented by formula (8) is approximately 6 or greater, the IOB satisfies the condition of being about 0.00-0.60. In a monoester of ethylene glycol (k = 2) and a fatty acid represented by formula (9), IOB is 0.57 when the number of carbons of the R⁸C portion is 12. Thus, when the total number of carbon atoms in the fatty acid composing a monoester of ethylene glycol (k = 2) and a fatty acid represented by formula (9) is approximately 12 or

greater, the IOB satisfies the condition of being about 0.00-0.60.

[0070]

Considering the potential for degradation by

oxidation and the like, the ester of the C2-C6 glycol and fatty acid is preferably a C2-C6 glycol and fatty acid ester, which is derived from a saturated fatty acid, i.e., an ester of a C₂-C6 glycol and a saturated fatty acid. [0071]

Also, in order to lower the IOB and result in greater hydrophobicity, the ester of the C₂-C6 glycol and fatty acid is preferably a glycol and fatty acid ester derived from a glycol with a greater number of carbons, such as an ester of a glycol and a fatty acid derived from butylene glycol, pentylene glycol or hexylene glycol.

Also, in order to lower the IOB and obtain in greater hydrophobicity, the ester of a C₂-C₆ glycol and fatty acid is preferably a diester.

Examples of commercial products of esters of C₂-C₆ glycols and fatty acids include COMPOL BL and COMPOL BS (both products of NOF Corp.).

[0072]

[ (B) Ether of (Bl) a compound having a chain hydrocarbon moiety and 2-4 hydroxyl groups substituting hydrogens on the chain hydrocarbon moiety and (B2) a compound having a chain hydrocarbon moiety and 1 hydroxyl group

substituting a hydrogen on the chain hydrocarbon moiety]

The (B) ether of (Bl) a compound having a chain hydrocarbon moiety and 2-4 hydroxyl groups substituting hydrogens on the chain hydrocarbon moiety and (B2) a compound having a chain hydrocarbon moiety and 1 hydroxyl group substituting a hydrogen on the chain hydrocarbon moiety (hereunder also referred to as "compound (B)" ) includes ethers of a compound with 4, 3 or 2 hydroxyl groups and a compound with 1 hydroxyl group, and it is not necessary for all of the hydroxyl groups to be etherified as long as the IOB, melting point and water solubility are within the aforementioned ranges.

[0073]

Compounds with Examples of (Bl) a compound having a chain hydrocarbon moiety and 2-4 hydroxyl groups

substituting hydrogens on the chain hydrocarbon moiety

(hereunder also referred to as "compound (Bl)") include those mentioned for "compound (A)",)" as compound (Al), such as pentaerythritol, glycerin and glycol.

Examples of (B2) a compound having a chain

hydrocarbon moiety and 1 hydroxyl group substituting a hydrogen on the chain hydrocarbon moiety (hereunder also referred to as "compound (B2)" ) include compounds wherein 1 hydrogen on the hydrocarbon is substituted with 1 hydroxyl group (-OH) , such as aliphatic monohydric alcohols, including saturated aliphatic monohydric alcohols and unsaturated aliphatic monohydric alcohols.

[0074]

Examples of saturated aliphatic monohydric alcohols include C₁-C2₀ saturated aliphatic monohydric alcohols, such as methyl alcohol (Ci) (Ci representing the number of carbon atoms, same hereunder) , ethyl alcohol (C₂) , propyl alcohol (C₃) and isomers thereof, including isopropyl alcohol (C₃) , butyl alcohol (C₄) and isomers thereof, including sec-butyl alcohol (C₄) and tert-butyl alcohol (C₄) , pentyl alcohol (C₅) , hexyl alcohol (C₆) , heptyl alcohol (C₇) , octyl alcohol (Cs) and isomers thereof, including 2-ethylhexyl alcohol (C₈) , nonyl alcohol (C₉) , decyl alcohol (C₁₀) , dodecyl alcohol (C₁₂) , tetradecyl alcohol (C14) , hexadecyl alcohol (Ci₆) , heptadecyl alcohol (Ci₇) , octadecyl alcohol (Ci₈) and eicosyl alcohol (C₂o) , as well as their isomers other than those mentioned.

Unsaturated aliphatic monohydric alcohols include those wherein 1 C-C single bond of a saturated aliphatic monohydric alcohol mentioned above is replaced with a C=C double bond, such as oleyl alcohol, and for example, these are commercially available by New Japan Chemical Co., Ltd. as the RIKACOL Series and UNJECOL Series.

[0075]

Examples for compound (B) include (bi) an ether of a chain hydrocarbon tetraol and at least one aliphatic monohydric alcohol, such as monoethers, diethers,

triethers and tetraethers, preferably diethers, triethers and tetraethers, more preferably triethers and

tetraethers and even more preferably tetraethers, (b₂) an ether of a chain hydrocarbon triol and at least one aliphatic monohydric alcohol, such as monoethers, diethers and triethers, preferably diethers and triethers and more preferably triethers, and (b₃) an ether of a chain hydrocarbon diol and at least one aliphatic

monohydric alcohols, such as monoethers and diethers, and preferably diethers.

[0076]

Examples of an ether of a chain hydrocarbon tetraol and at least one aliphatic monohydric alcohols include tetraethers, triethers, diethers and monoethers of pentaerythritol and aliphatic monohydric alcohols, represented by the following formulae (10) -(13):

wherein R¹⁰-R¹³ each represent a chain hydrocarbon.

[0077]

Examples of an ether of a chain hydrocarbon triol and at least one aliphatic monohydric alcohol include triethers, diethers and monoethers of glycerin and aliphatic monohydric alcohols, represented by the

following formulae (14)-(16): CH₂OR¹⁴

CHOR ⁵ (14)

I

CH₂OR¹⁶

CH₂OR¹⁴ CH₂OR¹⁴

I I

CHOH or CHOR¹⁵ ( 15)

I I

CH₂OR¹⁵ CH₂OH

CH₂OR¹⁴ CH₂OH

I

CHOH CHOR¹⁴ ( 16)

I I

CH₂OH CH₂OH

wherein R^14~R¹⁶ each represent a chain hydrocarbon.

[ 0078 ]

Examples of an ether of a chain hydrocarbon diol and at least one aliphatic monohydric alcohol include

diethers of C2-C6 glycols and aliphatic monohydric alcohols, represented by the following formula (17):

R¹⁷OC_nH_2nOR¹⁸ (17)

wherein n is an integer of 2-6, and R¹⁷ and R¹⁸ are each a chain hydrocarbon,

and monoethers of C₂-C6 glycols and aliphatic monohydric alcohols, represented by the following formula (18):

R¹⁷OC_nH_2nOH (18)

wherein n is an integer of 2-6, and R¹⁷ is a chain hydrocarbon.

[ 0079]

In the tetraether of pentaerythritol and an

aliphatic monohydric alcohol, the IOB is 0.44 when the total number of carbon atoms of the aliphatic monohydric alcohol composing the tetraether of pentaerythritol and the aliphatic monohydric alcohol, i.e., the total number of carbon atoms of the R¹⁰, R¹¹, R¹² and R¹³ portions in formula (10), is 4. Thus, when the total number of carbon atoms of the aliphatic monohydric alcohol

composing a tetraether of pentaerythritol and an aliphatic monohydric alcohol is approximately 4 or greater, the IOB value satisfies the condition of being within about 0.00 to 0.60.

[0080]

In the triether of pentaerythritol and an aliphatic monohydric alcohol, the IOB is 0.57 when the total number of carbon atoms of the aliphatic monohydric alcohol composing the triether of pentaerythritol and the

aliphatic monohydric alcohol, i.e., the total number of carbon atoms of the R¹⁰, R¹¹ and R¹² portions in formula (11), is 9. Thus, when the total number of carbon atoms of the aliphatic monohydric alcohol composing a triether of pentaerythritol and an aliphatic monohydric alcohol is approximately 9 or greater, the IOB value satisfies the condition of being within about 0.00 to 0.60.

[0081]

In the diether of pentaerythritol and an aliphatic monohydric alcohol, the IOB is 0.60 when the total number of carbon atoms of the aliphatic monohydric alcohol composing the diether of pentaerythritol and the

aliphatic monohydric alcohol, i.e., the total number of carbon atoms of the R¹⁰ and R¹¹ portions in formula (12), is 15. Thus, when the total number of carbon atoms of the aliphatic monohydric alcohol composing a diether of pentaerythritol and an aliphatic monohydric alcohol is approximately 15 or greater, the IOB value satisfies the condition of being within about 0.00 to 0.60.

[0082]

In the monoether of pentaerythritol and an aliphatic monohydric alcohol, the IOB is 0.59 when the number of carbon atoms of the aliphatic monohydric alcohol

composing the monoether of pentaerythritol and the aliphatic monohydric alcohol, i.e., the number of carbon atoms of the R¹⁰ portion in formula (13), is 22. Thus, when the number of carbon atoms of the aliphatic

monohydric alcohol comprising a monoether of

pentaerythritol and an aliphatic monohydric alcohol is approximately 22 or greater, the IOB value satisfies the condition of being within about 0.00 to 0.60.

[0083]

In the triether of glycerin and an aliphatic

monohydric alcohol, the IOB is 0.50 when the total number of carbon atoms of the aliphatic monohydric alcohol composing the triether of glycerin and the aliphatic monohydric alcohol, i.e., the total number of carbon atoms of the R¹⁴, R¹⁵ and R¹⁶ portions in formula (14), is 3. Thus, when the total number of carbon atoms of the aliphatic monohydric alcohol comprising a triether of glycerin and an aliphatic monohydric alcohol is

approximately 3 or greater, the IOB value satisfies the condition of being within about 0.00 to 0.60.

[0084]

In the diether of glycerin and an aliphatic

monohydric alcohol, the IOB is 0.58 when the total number of carbon atoms of the aliphatic monohydric alcohol composing the diether of glycerin and the aliphatic monohydric alcohol, i.e., the total number of carbon atoms of the R¹⁴ and R¹⁵ portions in formula (15), is 9. Thus, when the total number of carbon atoms of the aliphatic monohydric alcohol comprising a diether of glycerin and an aliphatic monohydric alcohol is

approximately 9 or greater, the IOB value satisfies the condition of being within about 0.00 to 0.60.

[0085]

In the monoether of glycerin and an aliphatic monohydric alcohol, the IOB is 0.58 when the number of carbon atoms of the aliphatic monohydric alcohol

composing the monoether of glycerin and the aliphatic monohydric alcohol, i.e., the number of carbon atoms of the R¹⁴ portion in formula (16), is 16. Thus, when the number of carbon atoms of the aliphatic monohydric alcohol comprising a monoether of glycerin and an

aliphatic monohydric alcohol is approximately 16 or greater, the IOB value satisfies the condition of being within about 0.00 to 0.60.

[0086]

In a diether of butylene glycol (n = 4) and

aliphatic monohydric alcohol represented by formula (17), the IOB is 0.33 when the total number of carbon atoms of the R¹⁷ and R¹⁸ portions is 2. Thus, when the number of carbon atoms of the aliphatic monohydric alcohol

comprising a diether of butylene glycol (n = 4) and an aliphatic monohydric alcohol represented by formula (17) is approximately 2 or greater, the IOB value satisfies the condition of being within about 0.00 to 0.60. Also, in a monoether of ethylene glycol (n = 2) and aliphatic monohydric alcohol represented by formula (18), the IOB is 0.60 when the number of carbon atoms of the R¹⁷ portion is 8. Thus, when the number of carbon atoms of the aliphatic monohydric alcohol in a monoether of ethylene glycol (n = 2) and an aliphatic monohydric alcohol represented by formula (18) is approximately 8 or

greater, the IOB value satisfies the condition of being within about 0.00 to 0.60.

[0087]

Compound (B) may be produced by dehydrating

condensation of a compound with 2-4 hydroxyl groups (Bl) and a compound with 1 hydroxyl group, such as an

aliphatic monohydric alcohol (B2), in the presence of an acid catalyst.

[0088]

[ (C) Ester of (CI) a carboxylic acid, hydroxy acid, alkoxy acid or oxoacid comprising a chain hydrocarbon moiety and 2-4 carboxyl groups substituting hydrogens on the chain hydrocarbon moiety and (C2) a compound having a chain hydrocarbon moiety and 1 hydroxyl group

substituting a hydrogen on the chain hydrocarbon moiety] The (C) ester of (CI) a carboxylic acid, hydroxy acid, alkoxy acid or oxoacid comprising a chain

hydrocarbon moiety and 2-4 carboxyl groups substituting hydrogens on the chain hydrocarbon moiety and (C2) a compound having a chain hydrocarbon moiety and 1 hydroxyl group substituting a hydrogen on the chain hydrocarbon moiety (hereunder also referred to as "compound (C)") includes esters of a compound with 4, 3 or 2 carboxyl groups and a compound with 1 hydroxyl group, and it is not necessary for all of the carboxyl groups to be esterified so long as the IOB, melting point and water solubility are within the aforementioned ranges.

[0089]

Examples of (CI) a carboxylic acid, hydroxy acid, alkoxy acid or oxoacid comprising a chain hydrocarbon moiety and 2-4 carboxyl groups substituting hydrogens on the chain hydrocarbon moiety (hereunder also referred to as "compound (CI)") include chain hydrocarbons

hydrocarbon carboxylic acids with 2-4 carboxyl groups, such as chain hydrocarbon dicarboxylic acids including alkanedicarboxylic acids such as ethanedioic acid, propanedioic acid, butanedioic acid, pentanedioic acid, hexanedioic acid, heptanedioic acid, octanedioic acid, nonanedioic acid and decanedioic acid, chain hydrocarbon tricarboxylic acids, including alkanetricarboxylic acids such as propanetrioic acid, butanetrioic acid,

pentanetrioic acid, hexanetrioic acid, heptanetrioic acid, octanetrioic acid, nonanetrioic acid and

decanetrioic acid, and chain hydrocarbon tetracarboxylic acids, including alkanetetracarboxylic acids such as butanetetraoic acid, pentanetetraoic acid, hexanetetraoic acid, heptanetetraoic acid, octanetetraoic acid,

nonanetetraoic acid and decanetetraoic acid.

[0090]

Compound (CI) includes chain hydrocarbon hydroxy acids with 2-4 carboxyl groups, including alkoxy acids with 2-4 carboxyl groups such as malic acid, tartaric acid, citric acid and isocitric acid, including chain hydrocarbon alkoxy acids with 2-4 carboxyl groups, such as O-acetylcitric acid, and chain hydrocarbon oxoacids with 2-4 carboxyl groups. Compounds (C2) having a chain hydrocarbon moiety and 1 hydroxyl group substituting a hydrogen on the chain hydrocarbon moiety include those mentioned for "compound (B) ", such as aliphatic monohydric alcohols.

[0091]

Compound (C) may be (ci) an ester, for example a monoester, diester, triester or tetraester, preferably a diester, triester or tetraester, more preferably a triester or tetraester and even more preferably a

tetraester, of a chain hydrocarbon tetracarboxylic acid, hydroxy acid, alkoxy acid or oxoacid with 4 carboxyl groups, and at least one aliphatic monohydric alcohol, (c₂) an ester, for example, a monoester, diester or triester, preferably a diester or triester and more preferably a triester, of a chain hydrocarbon

tricarboxylic acid, hydroxy acid, alkoxy acid or oxoacid with 3 carboxyl groups, and at least one aliphatic monohydric alcohol, or (c₃) an ester, for example, a monoester or diester, and preferably a diester, of a chain hydrocarbon dicarboxylic acid, hydroxy acid, alkoxy acid or oxoacid with 2 carboxyl groups, and at least one aliphatic monohydric alcohol.

Examples for compound (C) include dioctyl adipate and tributyl O-acetylcitrate, of which commercially available products exist.

[0092]

[ (D) Compound having a chain hydrocarbon moiety and one bond selected from the group consisting of an ether bond (-0-), carbonyl bond (-CO-) , ester bond (-C00-) and carbonate bond (-OCOO-) inserted in a chain hydrocarbon moiety and one bond selected from the group consisting of an ether bond (-0-) , carbonyl bond (-CO-), ester bond (- C00-) and carbonate bond (-OCOO-) inserted between a C-C single bond of the chain hydrocarbon moiety]

The (D) compound having a chain hydrocarbon moiety and one bond selected from the group consisting of an ether bond (-0-) , carbonyl bond (-CO-) , ester bond (-C00- ) and carbonate bond (-OCOO-) inserted in-between a C-C single bond of the chain hydrocarbon moiety (hereunder also referred to as "compound (D)") may be (di) an ether of an aliphatic monohydric alcohol and an aliphatic monohydric alcohol, (d₂) a dialkyl ketone, (d₃) an ester of a fatty acid and an aliphatic monohydric alcohol, or (d₄) a dialkyl carbonate.

[0093]

[ (di) Ether of an aliphatic monohydric alcohol and an aliphatic monohydric alcohol]

Ethers of aliphatic monohydric alcohols and

aliphatic monohydric alcohols include compounds having the following formula (19) :

R¹⁹OR²⁰ (19)

wherein R¹⁹ and R²⁰ each represent a chain

hydrocarbon .

[0094]

The aliphatic monohydric alcohol composing the ether (corresponding to R¹⁹0H and R²⁰OH in formula (19) ) is not particularly restricted so long as the ether satisfies the conditions for the IOB, melting point and water solubility, and for example, it may be one of the

aliphatic monohydric alcohols mentioned for "compound (B)".

[0095]

In an ether of an aliphatic monohydric alcohol and an aliphatic monohydric alcohol, the IOB is 0.50 when the total number of carbon atoms of the aliphatic monohydric alcohols composing the ether, i.e., the total number of carbons of the R¹⁹ and R²⁰ portions in formula (19), is 2, and therefore when the total number of carbons of the aliphatic monohydric alcohols comprising the ether is about 2 or greater, this condition for the IOB is

satisfied. However, when the total number of carbons of the aliphatic monohydric alcohols comprising the ether is about 6, the water solubility is as high as about 2 g, which is problematic from the viewpoint of vapor pressure as well. In order to satisfy the condition of a water solubility of about 0.00-0.05 g, the total number of carbons of the aliphatic monohydric alcohols comprising the ether is preferably about 8 or greater.

[0096]

[ (d₂) Dialkyl ketone]

The dialkyl ketone may be a compound of the

following formula (20):

R2i_COR22 ₍₂₀₎

wherein R²¹ and R²² are each an alkyl group.

[0097]

In a dialkyl ketone, the IOB is 0.54 when the total number of carbon atoms of R²¹ and R²² is 5, and therefore this condition for the IOB is satisfied if the total number of carbons is about 5 or greater. However, when the total number of carbons of dialkyl ketone is about 5, the water solubility is as high as about 2 g. Therefore, in order to satisfy the condition of a water solubility of about 0.00-0.05 g, the total number of carbons of dialkyl ketone is preferably about 8 or greater. In consideration of vapor pressure, the number of carbon atoms of dialkyl ketone is preferably about 10 or greater and more preferably about 12 or greater.

If the total number of carbon atoms of alkyl ketone is about 8, such as in 5-nonanone, for example, the melting point is approximately -50°C and the vapor pressure is about 230 Pa at 20°C.

The dialkyl ketone may be a commercially available product, or it may be obtained by a known method, such as by oxidation of a secondary alcohol with chromic acid or the like.

[0098]

[ (d₃) Ester of a fatty acid and an aliphatic monohydric alcohol]

Examples of esters of fatty acids and aliphatic monohydric alcohols include compounds having the

following formula (21) : R²³COOR²⁴ (21)

wherein R²³ and R²⁴ each represent a chain

hydrocarbon.

[0099]

Examples of fatty acids composing these esters

(corresponding to R²³COOH in formula (21) ) include the fatty acids mentioned for the " (ai) an ester of a chain hydrocarbon tetraol and at least one fatty acids", and specifically these include saturated fatty acids and unsaturated fatty acids, with saturated fatty acids being preferred in consideration of the potential for

degradation by oxidation and the like. The aliphatic monohydric alcohol composing the ester (corresponding to R²⁴OH in formula (21) ) may be one of the aliphatic

monohydric alcohols mentioned for "compound (B)".

[0100]

In an ester of such a fatty acid and aliphatic monohydric alcohol, the IOB is 0.60 when the total number of carbon atoms of the fatty acid and aliphatic

monohydric alcohol, i.e., the total number of carbon atoms of the R²³C and R²⁴ portion in formula (21), is 5, and therefore this condition for the IOB is satisfied when the total number of carbon atoms of the R²³C and R²⁴ portion is about 5 or greater. However, with butyl acetate in which the total number of carbon atoms is 6, the vapor pressure is high at greater than 2000 Pa. In consideration of vapor pressure, therefore, the total number of carbon atoms is preferably about 12 or greater. If the total number of carbon atoms is about 11 or greater, it will be possible to satisfy the condition of a water solubility of about 0.00-0.05 g.

[0101]

Examples of esters of such fatty acids and aliphatic monohydric alcohols include esters of dodecanoic acid (C_i2) and dodecyl alcohol (C12) and esters of tetradecanoic acid (Ci₄) and dodecyl alcohol (C12) , and examples of commercial products of esters of such fatty acids and aliphatic monohydric alcohols include ELECTOL WE20 and

ELECTOL WE40 (both products of NOF Corp.).

[0102]

[ (d₄) Dialkyl carbonate]

The dialkyl carbonate may be a compound of the following formula (22):

R²⁵OC (=0) OR²⁶ (22)

wherein R²⁵ and R²⁶ are each an alkyl group.

[0103]

In a dialkyl carbonate, the IOB is 0.57 when the total number of carbon atoms of R²⁵ and R²⁶ is 6, and therefore this condition for the IOB is satisfied if the total number of carbons of R²⁵ and R²⁶ is about 6 or greater .

In consideration of water solubility, the total number of carbon atoms of R²⁵ and R²⁶ is preferably about 7 or greater and more preferably about 9 or greater.

The dialkyl carbonate may be a commercially

available product, or it may be synthesized by reaction between phosgene and an alcohol, reaction between formic chloride and an alcohol or alcoholate, or reaction between silver carbonate and an alkyl iodide.

[0104]

[ (E) Polyoxy C₂-C₆ alkylene glycol, or alkyl ester or alkyl ether thereof]

The (E) polyoxy C₂-6 alkylene glycol, or alkyl ester or alkyl ether thereof (hereunder also referred to as "compound (E)") may be (e_x) a polyoxy C2-6 alkylene glycol, (e₂) an ester of a polyoxy C₂-6 alkylene glycol and at least one a fatty acid, (e₃) an ether of a polyoxy C₂-6 alkylene glycol and at least one aliphatic monohydric alcohol, (e₄) an ester of polyoxy C₂_₆ alkylene glycol and chain hydrocarbon tetracarboxylic acid, chain hydrocarbon tricarboxylic acid or chain hydrocarbon dicarboxylic acid., or (e₅) an ether of polyoxy C₂_₆ alkylene glycol and a chain hydrocarbon tetraol, chain hydrocarbon triol or chain hydrocarbon diol . These will now be explained. [0105]

[ (θχ) Polyoxy C₂-C₆ alkylene glycol]

The polyoxy C₂-C₆ alkylene glycol is i) a homopolymer having one backbone selected from the group consisting of polyoxy C₂-C6 alkylene backbones, i.e. oxyethylene

backbone, oxypropylene backbone, oxybutylene backbone, oxypentylene backbone and oxyhexylene backbone, and having hydroxy groups at both ends, ii) a block copolymer having a backbone of 2 or more selected from among the aforementioned group and having hydroxy groups at both ends, or iii) a random copolymer having a backbone of two or more selected from among the aforementioned group and having hydroxy groups at both ends .

[0106]

The polyoxy C₂-C₆ alkylene backbone is preferably an oxypropylene backbone, oxybutylene backbone, oxypentylene backbone or oxyhexylene backbone and more preferably an oxybutylene backbone, oxypentylene backbone or

oxyhexylene backbone, from the viewpoint of lowering the IOB of the polyoxy C₂-C₆ alkylene glycol.

[0107]

When polyoxy C₂-C₆ alkylene glycol is a homopolymer, the poly C₃-₆ alkylene glycol is represented by the

following formula (23) :

HO-(C_mH_2mO)_n-H (23)

wherein m is an integer of 3-6.

[0108]

The present inventors have confirmed that in

polyethylene glycol (corresponding to formula (23) where m = 2) , when n > 45 (the molecular weight exceeds about

2,000), the condition for IOB of about 0.00 to about 0.60 is satisfied, but the condition for the water solubility is not satisfied even when the molecular weight exceeds 4,000. Therefore, ethylene glycol homopolymer is not included in the (ei) polyoxy C₂-6 alkylene glycol, and ethylene glycol should be included in the (ej_.) polyoxy C₂_6 alkylene glycol only as a copolymer or random polymer with another glycol.

[0109]

Thus, homopolymers of formula (23) may include propylene glycol, butylene glycol, pentylene glycol or hexylene glycol homopolymer.

For this reason, m in formula (23) is about 3 to 6 and preferably about 4 to 6, and n is 2 or greater.

[0110]

The value of n in formula (23) is a value such that the polyoxy C₂ -6 alkylene glycol has an IOB of about 0.00-

0.60, a melting point of no higher than about 45°C and a water solubility of no greater than about 0.05 g in 100 g of water at 25°C.

For example, when formula (23) is polypropylene glycol (m = 3), the IOB is 0.58 when n = 12. Thus, when formula (23) is polypropylene glycol (m = 3), the

condition for the IOB is satisfied when n is equal to or greater than about 12.

Also, when formula (23) is polybutylene glycol (m = 4), the IOB is 0.57 when n = 7. Thus, when formula (23) is polybutylene glycol (m = 4), the condition for the IOB is satisfied when n is equal to or greater than about 7.

[0111]

From the viewpoint of IOB, melting point and water solubility, the weight-average molecular weight of the polyoxy C₂- 6 alkylene glycol is preferably between about 200 and about 10,000, more preferably between about 250 and about 8,000, and even more preferably in the range of about 250 to about 5,000.

Also from the viewpoint of IOB, melting point and water solubility, the weight-average molecular weight of a poly C₃ alkylene glycol, i.e. polypropylene glycol, is preferably between about 1,000 and about 10,000, more preferably between about 3,000 and about 8,000, and even more preferably between about 4,000 and about 5,000.

This is because if the weight-average molecular weight is less than about 1,000, the condition for the water solubility will not be satisfied, and a larger weight- average molecular weight will particularly tend to increase the migration rate into the absorbent body and the whiteness of the top sheet.

[0112]

Examples of commercial products of polyoxy C₂-₆ alkylene glycols include UNIOL™ D-1000, D1200, D-2000, D- 3000, D-4000, PB-500 and PB-700 (both products of NOF Corp . ) .

[0113]

[ (e₂) Ester of polyoxy C₂-6 alkylene glycol and at least one fatty acid]

Esters of such polyoxy C₂-6 alkylene glycols and at least one fatty acid include the polyoxy C₂_₆ alkylene glycols mentioned for " (ei) Polyoxy C₂-6 alkylene glycol" in which one or both OH ends have been esterified with fatty acids, i.e., monoesters and diesters..

[0114]

Examples of fatty acids to be esterified in the ester of a polyoxy C₂-6 alkylene glycol and at least one fatty acid include the fatty acids mentioned for the " (ai) Esters of chain hydrocarbon tetraols and at least one fatty acid", and specifically these include saturated fatty acids and unsaturated fatty acids, with saturated fatty acids being preferred in consideration of the potential for degradation by oxidation and the like. An example of a commercially available ester of a polyoxy C₂-6 alkylene glycol and a fatty acid us WILLBRITE cp9 (product of NOF Corp.).

[0115]

[ (e₃) Ether of polyoxy C₂-6 alkylene glycol and at least one aliphatic monohydric alcohol]

Ethers of such polyoxy C₂_₆ alkylene glycols and at least one aliphatic monohydric alcohol include the polyoxy C₂-₆ alkylene glycols mentioned for " (ei) polyoxy

C₂_6 alkylene glycol" wherein one or both OH ends have been etherified by an aliphatic monohydric alcohol, i.e., monoethers and diethers.

In an ether of a polyoxy C₂-6 alkylene glycol and at least one aliphatic monohydric alcohol, the aliphatic monohydric alcohol to be etherified may be an aliphatic monohydric alcohol among those mentioned for "compound (B) ".

[0116]

[ (e₄) Ester of polyoxy C₂-6 alkylene glycol and chain hydrocarbon tetracarboxylic acid, chain hydrocarbon tricarboxylic acid or chain hydrocarbon dicarboxylic acid]

The polyoxy C₂-6 alkylene glycol to be esterified for the aforementioned ester of a polyoxy C2-6 alkylene glycol and a chain hydrocarbon tetracarboxylic acid, chain hydrocarbon tricarboxylic acid or chain hydrocarbon dicarboxylic acid may be any of the polyoxy C2-6 alkylene glycols mentioned above under " (ei) Polyoxy C₂-6 alkylene glycol". Also, the chain hydrocarbon tetracarboxylic acid, chain hydrocarbon tricarboxylic acid or chain hydrocarbon dicarboxylic acid to be esterified may be any of those mentioned above for "compound (C)".

[0117]

The ester of a polyoxy C2-6 alkylene glycol and a chain hydrocarbon tetracarboxylic acid, chain hydrocarbon tricarboxylic acid or chain hydrocarbon dicarboxylic acid may be a commercially available product, or it may be produced by polycondensation of a polyoxy C2-6 alkylene glycol with a chain hydrocarbon tetracarboxylic acid, chain hydrocarbon tricarboxylic acid or chain hydrocarbon dicarboxylic acid under known conditions.

[0118]

[ (e₅) Ether of polyoxy C2-6 alkylene glycol and chain hydrocarbon tetraol, chain hydrocarbon triol or chain hydrocarbon diol]

The polyoxy C₂-6 alkylene glycol to be etherified for the aforementioned ether of a polyoxy C2-6 alkylene glycol and a chain hydrocarbon tetraol, chain hydrocarbon triol or chain hydrocarbon diol may be any of the polyoxy C₂-6 alkylene glycols mentioned above under " (ei) Polyoxy C₂-₆ alkylene glycol". Also, the chain hydrocarbon tetraol, chain hydrocarbon triol or chain hydrocarbon diol to be etherified may be, for example, pentaerythritol, glycerin or glycol, mentioned above for "compound (A)".

[0119]

Examples of commercially available ethers of polyoxy

C₂-6 alkylene glycols and chain hydrocarbon tetraols, chain hydrocarbon triols and chain hydrocarbon diols include UNILUBE™ 5TP-300KB and UNIOL™ TG-3000 and TG-4000

(products of NOF Corp.).

UNILUBE™ 5TP-300KB is a compound obtained by

polycondensation of 65 mol of propylene glycol and 5 mol of ethylene glycol with 1 mol of pentaerythritol, and it has an IOB of 0.39, a melting point of below 45°C, and a water solubility of less than 0.05 g.

[0120]

UNIOL™ TG-3000 is a compound obtained by

polycondensation of 50 mol of propylene glycol with 1 mol of glycerin, and it has an IOB of 0.42, a melting point of below 45°C, a water solubility of less than 0.05 g, and a weight-average molecular weight of about 3,000.

UNIOL™ TG-4000 is a compound obtained by

polycondensation of 70 mol of propylene glycol with 1 mol of glycerin, and it has an IOB of 0.40, a melting point of below 45°C, a water solubility of less than 0.05 g, and a weight-average molecular weight of about 4,000.

[0121]

The ether of a poly C₂-6 alkylene glycol and a chain hydrocarbon tetraol, chain hydrocarbon triol or chain hydrocarbon diol may also be produced by polycondensation of a polyoxy C₂-6 alkylene glycol with a chain hydrocarbon tetraol, chain hydrocarbon triol or chain hydrocarbon diol under known conditions.

[0122] [ (F) Chain hydrocarbon]

The chain hydrocarbon has an inorganic value of 0 and thus an IOB of 0.00, while the water solubility is also approximately 0 g, and therefore if the melting point is no higher than about 45°C, it may be included among the aforementioned blood modifying agents.

Examples of such chain hydrocarbons include (fi) chain alkanes, such as linear alkanes and branched alkanes, and linear alkanes generally include those with no more than 22 carbons, in consideration of a melting point of no higher than about 45°C. In consideration of vapor pressure, they generally include those with 13 or more carbons. Branched alkanes generally include those with 22 or more carbons, since their melting points are often lower than linear alkanes, given the same number of carbon atoms.

Examples of commercially available hydrocarbon products include PARLEAM 6 (NOF Corp.).

[0123]

The blood modifying agent has been found to have at least function of lowering blood viscosity and surface tension, which will be considered in detail in the examples. Menstrual blood to be absorbed by the

absorbent article contains proteins of the endometrial wall, for example, unlike ordinary blood, which act to bind together blood cells, such that the blood cells form a rouleau state. The menstrual blood to be absorbed by the absorbent article therefore tends to have high viscosity, and if the top sheet is a nonwoven fabric of woven fabric, the menstrual blood becomes clogged between the fibers creating a residual sticky feel for the wearer, while the menstrual blood also diffuses on the surface of the top sheet and tends to leak.

[0124]

Also, the blood modifying agent which has an IOB of about 0.00 to 0.60 has high organicity and readily infiltrates between blood cells, and it therefore stabilizes the blood cells and can prevent formation of a rouleau structure by the blood cells.

Since the blood modifying agent stabilizes blood cells and helps to prevent formation of a rouleau

structure by the blood cells, it facilitates absorption of menstrual blood by the absorbent body. For example, with an absorbent article comprising an acrylic super- absorbent polymer, or SAP, absorption of menstrual blood is known to lead to covering of the SAP surface by rouleau-formed blood cells and inhibition of the

absorption performance of the SAP, but presumably

stabilization of the blood cells allows the absorption performance of the SAP to be exhibited more easily. In addition, the blood modifying agent which has high affinity with erythrocytes protects the erythrocyte membranes, and therefore may minimize destruction of the erythrocytes .

[0125]

In this absorbent article, the top sheet comprises the blood modifying agent at a basis weight in the range of preferably 1-30 g/m², more preferably 2-20 g/m² and more preferably 3-10 g/m². If the basis weight of the blood modifying agent is less than about 1 g/m², the blood modifying effect will tend to be insufficient, and if the basis weight of the blood modifying agent is increased, the stickiness during wearing will tend to be increased.

[0126]

The absorbent article of the present invention may be manufactured by methods known in the art.

There are no particular restrictions on the method of coating the blood modifying agent, and coating may be accomplished with heating as necessary, using a non- contact coater, for example, a spiral coater, curtain coater, spray coater or dip coater, or a contact coater or the like. A non-contact coater is preferred from the viewpoint of uniformly dispersing the droplet or

particulate modifying agent throughout, and from the viewpoint of not causing damage in the material. The blood modifying agent may be coated directly, if it is a liquid at room temperature, or it may be heated to lower the viscosity, and when it is a solid at room

temperature, it may be heated to liquefaction and coated through a control seam HMA (hot melt adhesive) gun. By increasing the air pressure of the control seam HMA gun, it is possible to coat the blood modifying agent as fine particulates .

[0127]

The blood modifying agent may be coated during production of the top sheet material, such as the

nonwoven fabric, or it may be coated in the manufacturing line for production of the absorbent article. From the viewpoint of minimizing equipment investment, the blood modifying agent is preferably coated in the manufacturing line for the absorbent article, and in order to prevent shedding of the blood modifying agent which may

contaminate the line, the blood modifying agent is preferably coated during a step downstream from the manufacturing line, and specifically, immediately before encapsulation of the product in an individual package.

[0128]

The blood modifying agent preferably has a weight- average molecular weight of no greater than about 2,000, and more preferably it has a weight-average molecular weight of no greater than about 1,000. This is because a high weight-average molecular weight will make it

difficult to lower the viscosity of the blood modifying agent to an appropriate viscosity for coating, and may require dilution with a solvent. In addition, a high number-average molecular weight will create tack in the blood modifying agent and may produce an unpleasant feeling for the wearer.

[0129]

The back sheet 3 shown in Fig. 1 and Fig. 2 prevents body fluid that has been absorbed into the absorbent body 4 from leaking to the outside. A material that is impermeable to body fluids is used for the back sheet 3. The material used for the back sheet 3 may be, for example, a hydrophobic nonwoven fabric, an impermeable plastic film of polyethylene, polypropylene or the like, or a laminate sheet with nonwoven fabric and an

impermeable plastic film. The material used for the back sheet 3 may also be an SMS ( spunbond-meltblown-spunbond) nonwoven fabric obtained by sandwiching a highly water- resistant meltblown nonwoven fabric between high-strength spunbond nonwoven fabrics. By using a material which is permeable to air and not permeable to body fluids as the back sheet 3, it is possible to reduce mustiness during wearing.

[0130]

The absorbent body 4 absorbs and retains body fluids. The absorbent body 4 preferably has high bulk, is resistant to deformation and has low chemical

irritation. For example, the absorbent body 4 may be a composite absorbent body composed of fluffy pulp or an airlaid nonwoven fabric, and a super-absorbent polymer (SAP) . The composite absorbent body may also be covered with a liquid-permeable material such as a tissue.

[0131]

Instead of fluffy pulp in the composite absorbent body, there may be used, for example, chemical pulp, cellulose fiber, or artificial cellulose fiber such as rayon and acetate. The basis weight of the absorbent fiber such as pulp in the composite absorbent body is preferably at least 100 g/m² and no greater than 800 g/m², and the mass ratio of the super-absorbent polymer in the composite absorbent body is preferably at least 10% and no greater than 65%, with the absorbent fiber defined as 100%. The basis weight of the liquid-permeable material such as a tissue covering the composite mixture is preferably at least 12 g/m² and no greater than 30 g/m².

[0132] An airlaid nonwoven fabric of the composite mixture may be, for example, a nonwoven fabric comprising pulp and synthetic fiber heat sealed together, or a nonwoven fabric comprising pulp and synthetic fiber fixed with a binder.

[0133]

The super-absorbent polymer of the composite

absorbent body has a three-dimensional network structure with appropriate crosslinking of a water-soluble polymer. The absorbent polymer absorbs 30 to 60 times the amount of water relative to the volume of the absorbent polymer before absorption of water. However, the absorbent polymer is essentially water-insoluble. The absorbent polymer does not exude absorbed water even when a

moderate degree of pressure is applied. The absorbent polymer used is, for example, a starch-based, acrylic acid-based or amino acid-based particulate or filamentous polymer .

[0134]

The shape and structure of the absorbent body may be varied if necessary, but the total absorption by the absorbent body 4 must be suitable for the designed insertion volume and the desired use of the absorbent article 1. The size and absorbing power of the absorbent body 4 will also vary depending on the intended use.

[0135]

In the particular embodiment shown in Figs. 1 and 2, wing sections 5 are provided in the absorbent article 1 to stably anchor the absorbent article 1 to underwear. After the wing sections 5 have been folded on the outer side of the underwear, it is attached to the crotch section of the underwear through the attachment part 6 to allow the absorbent article 1 to be stably anchored to the underwear.

[0136]

The attachment part 6 shown in the particular embodiment illustrated in Figs. 1 and 2 anchors the absorbent article 1 to the crotch section of the

underwear. A pressure-sensitive adhesive may be used to form the attachment part 6 and is preferably, for

example, one composed mainly of a styrene-based polymer, tackifier or plasticizer. Styrene-based polymers include styrene-ethylene-butylene-styrene block copolymer, styrene-butylene polymer, styrene-butylene-styrene block copolymer and styrene-isobutylene-styrene copolymer, any of which may be used alone or as polymer blends of two or more. Styrene-ethylene-butylene-styrene block copolymer is preferred among these from the viewpoint of

satisfactory thermostability.

[0137]

The tackifier and plasticizer mentioned above are preferably solids at ordinary temperature, and these include tackifiers such as C5 petroleum resin, C9

petroleum resin, dicyclopentadiene-based petroleum resin, rosin-based petroleum resin, polyterpene resin,

terpenephenol resin and the like, and plasticizers such as monomer plasticizers including tricresyl phosphate, dibutyl phthalate and dioctyl phthalate, and polymer plasticizers including vinyl polymers and polyesters.

[0138]

Bonding the top sheet 2 to the back sheet 3 by heat embossing will form a seal section 7 on both sides of the absorbent article 1 in the lengthwise direction.

[0139]

One method for producing the top sheet 2A of the absorbent article 1 according to the first embodiment of the invention will now be explained with reference to

Fig. 4. Fig. 4 is an illustration of a top sheet

production apparatus 100A to be used in a method for producing a top sheet 2A according to the first

embodiment of the invention. The top sheet production apparatus 100A comprises a recess-forming roll 120A, a stretching gear roll 130 and a lubricant coating sprayer 140. The method for producing the top sheet 2A comprises a step of preparing a resin film, a recess-forming step, a gear stretching step and a lubricant coating step.

[0140]

In the step of preparing the resin film, a resin film 102A supplied from a resin film roll (not shown) is fed to the recess-forming roll 120A.

[0141]

In the recess-forming step, the heated resin film 102A (see Fig. 8(a)) is passed through the recess-forming roll 120A to create a resin film 103A with recesses 104A formed therein (see Fig. 8 (b) ) . The recess-forming roll 120A comprises a roulette roll 121A and a preheated roll 122A with a smooth surface.

[0142]

Fig. 5(a) and (b) show examples of the roulette roll

121A. Fig. 5(a) shows the entire roulette roll 121A, and Fig. 5(b) is a magnified view of section 123A of the surface of the roulette roll 121A that contacts with the resin film 102A when the resin film 102A passes between the roulette roll 121A and the roll 122A which has a smooth surface. Fig. 5(c) shows an example of the preheated roll 122A which has a smooth surface. Latticelike convexities 124A are formed on the surface 123A of the roulette roll 121A. As a result, rhomboid recesses 125A are formed in the surface of the roulette roll 121A.

[0143]

The center line spacing between the convexities 124A extending parallel on the lattice-like convexities 124A, i.e., the pitch of the lattice-like convexities 124A, is preferably at least 0.2 mm and no greater than 10 mm and more preferably at least 0.4 mm and no greater than 2 mm. If the pitch of the lattice-like convexities 124A is less than 0.2 mm, or greater than 10 mm, recesses may not form in the resin film. The widths of the lattice-like convexities 124A are preferably at least 0.01 mm and no greater than 1 mm, and more preferably at least 0.03 mm and no greater than 0.1 mm. The lengths of the sides of the rhomboid recesses 125A are preferably at least 0.1 mm and no greater than 5 mm, and more preferably at least 0.2 mm and no greater than 1 mm. If the widths of the lattice-like convexities 124A are less than 0.01 mm or greater than 1 mm, or if the lengths of the sides of the rhomboid recesses 125A are less than 0.1 mm or greater than 5 mm, recesses may not form in the resin film.

[0144]

The preheated roll 122A with a smooth surface is kept at a temperature between 70°C and 100°C, and it heats the fed resin film 102A. This softens the resin film 102A and facilitates formation.

[0145]

When the resin film 102A passes between the roulette roll 121A and the roll 122A with a smooth surface, the resin film 102A receives pressure in the thickness direction at the sections in contact with the latticelike convexities 124A, and roughly rectangular recesses 104A as shown in Fig. 8 (b) are formed in the resin film 102A. The shapes of the recesses 125A of the roulette roll 121A are not limited to being rhomboid, and may instead be square, rectangular, parallelogram-shaped, trapezoid, triangular, hexagonal, or the like.

[0146]

In the gear stretching step, passing the recess- formed resin film 103A through the stretching gear roll 130 shown in Fig. 4 creates a resin film 105A having protrusions 21A and openings 25A formed therein (see Fig. 8(c)). Fig. 6(a) shows the upper gear roll 131 of the stretching gear roll 130. Fig. 6(b) is an illustration of the gear teeth 133 arranged on the peripheral surface of the upper gear roll 131. The gear teeth 133 extend in the circumferential direction of the upper gear roll 131. The angles of the gear teeth 133 are chamfered in an R- shape in order to prevent the resin film 103A from being cut by the angles of the gear teeth 133 when the resin film 103A (see Fig. 8(b)) has passed through the stretching gear roll 130.

[0147]

The widths of the gear teeth 133 are 0.3-0.5 mm, for example, and the distance between adjacent gear teeth 133 is 1.0-1.2 mm, for example. The lower gear roll 132 of the gear roll 130 has the same shape as the upper gear roll 131, and therefore the lower gear roll 132 will not be explained in detail. The length of the upper gear roll 131 in the radial direction at the section where the gear teeth 133 of the upper gear roll 131 engage with the gear teeth of the lower gear roll 132, i.e. the

engagement depth, is 1.25 mm, for example. The gaps between the gear teeth 133 of the upper gear roll 131 and the gear teeth of the lower gear roll 132, when the gear teeth 133 of the upper gear roll 131 and the gear teeth of the lower gear roll 132 have been engaged, are 0.25- 0.45 mm, for example.

[0148]

When the resin film 103A passes through the

stretching gear roll 130, the resin film 103A is formed in an essentially undulating manner, creating a resin film 105A with protrusions 21A formed therein (see Fig. 8 (c) ) .

[0149]

The principle by which openings 25A are formed in the resin film 103A after the resin film 103A has passed through the stretching gear roll 130 will now be

explained with reference to Fig. 7. The explanation of this principle is not intended to limit the scope of the invention.

[0150]

The resin film 103A is stretched to a large degree at the sections 106A where the gear teeth 133 of the upper gear roll 131 and the gear teeth 134 of the lower gear roll 132 are engaged. The sections where the recesses 104A have been formed in the step of forming the recesses are sections where the basis weight of the resin film 103A vary in an abrupt manner, and therefore the strength is low and the recesses 104A of the resin film 103A will tear when stretched (drawn) . Consequently, the recesses 104A of the resin film 103A tear at the sections 106A of the resin film 103A that have been drawn, such that the torn sections of the resin film 103A widen, forming openings 25A.

[0151]

The resin film 103A is not significantly drawn at the sections 107A where the gear teeth 133 of the upper gear roll 131 and the gear teeth 134 of the lower gear roll 132 are not engaged. Consequently, even when the resin film 103A passes through the stretching gear roll 130, the recesses 104A formed in the recess-forming step are not torn and do not become openings at the sections

107A of the resin film 103A where the gear teeth 133 of the upper gear roll 131 and the gear teeth 134 of the lower gear roll 132 are not engaged. Also, the recesses 104A formed in the step of forming the recesses are slightly drawn and become recesses 26A in the top sheet

2.

[0152]

The sections 107A of the resin film 103A where the gear teeth 133 of the upper gear roll 131 and the gear teeth 134 of the lower gear roll 132 are not engaged correspond to the top sections 23A of the protrusions 21 and bottom sections 22A in the top sheet 2A (see Fig. 3) . The sections 106A of the resin film 103A where the gear teeth 133 of the upper gear roll 131 and the gear teeth 134 of the lower gear roll 132 are engaged correspond to the wall sections 24A of the protrusions 21A in the top sheet 2A (see Fig. 3) . Consequently, recesses 26A are formed in the top sections 23A and bottom sections 22A of the protrusions 21A in the top sheet 2A, and openings 25A are formed in the wall sections 24A of the protrusions

21A in the top sheet 2A.

[0153] When the resin film used for the top sheet 2A is drawn, it is decreased in thickness and has a lower concealing property. Therefore, when the absorbent article 1 is viewed from above the skin facing side, body fluid that has been absorbed into the absorbent body 4 is hidden from sight at the bottom sections 22A and the top sections 23A of the protrusions 21A in the top sheet 2A, but when the absorbent article 1 is viewed from an oblique direction, body fluid that has been absorbed into the absorbent body 4 can be seen through the wall

sections 24A of the protrusions 21A in the top sheet 2A and through the openings 25A of the wall sections 24A. Therefore, when the user wishes to determine whether the absorbent article 1 needs replacement, the amount of body fluid absorbed into the absorbent body 4 can be confirmed by viewing the absorbent article 1 from an oblique direction, thereby allowing the need for replacement of the absorbent article 1 to be ascertained.

[0154]

In the lubricant coating step, a lubricant coating sprayer 140 is used to coat the lubricant 141 onto the resin film 105A that has been gear stretched, creating a resin film 108A having a lubricant layer 27A formed on the surface (see Fig. 8(d)). The coating amount of the lubricant is preferably at least 0.1 g/m² and no greater than 30.0 g/m², and more preferably at least 1.0 g/m² and no greater than 10.0 g/m². If the coating amount of the lubricant is less than 0.1 g/m², the effect on wipeability of body fluid by the lubricant may not be obtained. If the coating amount of the lubricant is greater than 30.0 g/m², the wearer may experience a wetted feel on the surface of the top sheet 2A.

[0155]

The lubricant may be coated over the entire surface of the resin film 105A, or the lubricant may be coated on the resin film 105A only at the regions corresponding to the areas of the absorbent article where body fluid of the wearer will be excreted. Here, the lubricant coating sprayer 140 coats the lubricant 141 onto the resin film 105A by spraying in the step of coating the lubricant, but the lubricant 141 may instead be coated onto the resin film 105A by a printing method or dipping method.

[0156]

An example of conditions for forming a top sheet are shown below.

Resin film material: Low-density polyethylene (LDPE) Resin film basis weight: 23.5 g/m² or 35.0 g/m²

Resin film thickness: 20 μπι or 30 μπι

Titanium oxide content of resin film: 2.9% or 5%

Preheated roll temperature: 80°C

Pitch of lattice-like convexities on roulette roll: 0.4 mm

Gear tooth width: 0.5 mm

Distance between adjacent gear teeth: 1.0 mm

Gap between upper gear roll gear teeth and lower gear roll gear teeth: 0.25 mm

Stretching gear roll engagement depth: 1.25 mm

[0157]

Fig. 9(a) shows lattice-like convexities 124A and rhomboid recesses 125A formed on the surface of a

roulette roll.

[0158]

Fig. 9(b) shows recesses 104A formed in a resin film that has passed through a recess-forming roll 120A. The length of the recesses 104A in the cross-machine

direction (CD) was 0.25 mm. The pitch of the recesses 104A in the cross-machine direction (CD) was 0.70 mm.

Here, the pitch of the recesses 104A in the cross-machine direction is the distance between the right sides of the recesses 104A in the cross-machine direction, which are adjacent in the transverse direction in Fig. 9(b) .

[0159]

Fig. 9(c) shows parts of openings 25A formed in the wall sections 24A of protrusions and of the recesses 26 formed in the top sections 23A of protrusions, after passing through a stretching gear roll 130A. Fig. 9(c) was photographed after stretching the resin film which was formed in an essentially undulating manner in order to match the focus of the microscope with the entire resin film.

[0160]

- Second embodiment -

A second embodiment of the invention will now be described with reference to the accompanying drawings, with the understanding that the invention is not limited to the examples depicted in the drawings. Parts in common with the first embodiment of the invention will be denoted by like reference numerals, and the differences from the first embodiment will be explained.

[0161]

The construction of the absorbent article of the second embodiment of the invention is the same as that of the absorbent article 1 of the first embodiment except for the top sheet, and therefore the focus of explanation will be on the top sheet of the absorbent article of the second embodiment .

[0162]

Fig. 10 is a schematic perspective view of the top sheet 2B of an absorbent article according to the second embodiment. A top sheet 2B formed such that the

widthwise cross-section is essentially undulating has protrusions 21B extending in the lengthwise direction and bottom sections 22B arranged between adjacent protrusions 21B. The direction in which the protrusions 21B extend is not limited to the lengthwise direction. The

protrusions 21B each has a top section 23B as the side that contacts the skin of the wearer, and wall sections 24B on the sides. Since the top sheet 2B of the

absorbent article of the second embodiment is also formed so that the cross-section is an essentially undulating shape, the top sheet 2B is flattened as the essentially undulating shape of the top sheet 2B is deformed by pressure applied to the surface of the top sheet 2B when body fluid such as menstrual blood is wiped off by the wearer using toilet paper or the like, thereby

facilitating the act of wiping off body fluid that has adhered onto the surface of the top sheet 2B.

[0163]

In this embodiment the top sheet 2B includes a resin film layer 31B having a plurality of openings 34B formed for permeation of body fluid, a lubricant layer 33B formed on the skin facing side of the resin film layer 31B and a fiber aggregate layer 32B formed on the non- skin facing side of the resin film layer 31B. The fiber aggregate layer 32B has its matrix disrupted at the wall sections 24B of the protrusions 21B. Here, "matrix disrupted" means that the fiber aggregate layer 32B has undergone disruption at the interior of the fiber

aggregate layer, such as ripping of the fiber aggregate layer 32B.

[0164]

The resin used in the resin film layer 31B is the same as that of the top sheet of the absorbent article of the first embodiment, and therefore explanation of the resin used in the resin film layer 31B will be omitted here.

[0165]

The basis weight of the resin film layer 31B is preferably at least 1 g/m² and no greater than 30 g/m², and more preferably at least 3 g/m² and no greater than 15 g/m². The thickness of the resin film layer 31B is preferably at least 0.01 mm and no greater than 0.3 mm, and more preferably at least 0.03 mm and no greater than 0.15 mm. If the thickness of the resin film layer 31B is less than 0.01 mm, the concealing property of the top sheet 2B, described hereunder, may be too low, while if the thickness of the resin film layer 31B exceeds 0.3 mm, the stiffness of the top sheet 2B may be increased and irritation by the top sheet 2B on the skin of the wearer may be too strong. Also, if the thickness of the resin film layer 31B exceeds 0.3 mm, the strength of the resin film layer 31B will be excessively high and openings 34B may not be formed in the resin film layer 31B.

[0166]

The top sheet 2B may have a concealing property so that body fluids absorbed into the absorbent body cannot be seen from the exterior, similar to the top sheet 2 of the absorbent article of the first embodiment. The concealing property of the top sheet 2 may be exhibited by the concealing property of the resin film layer 31. The concealing property of the resin film layer 31 is produced by mixing an inorganic filler such as titanium oxide with a resin. When the filler is titanium oxide, the titanium oxide content is preferably at least 1% and no greater than 50%, and more preferably at least 3% and no greater than 15%, with respect to the weight of the resin. If the titanium oxide content is less than 1% with respect to the weight of the resin, the concealing effect of the top sheet 2B for body fluids absorbed into the absorbent body may be too small. If the titanium oxide content exceeds 50% of the weight of the resin film, it may become difficult to create a laminar form from the titanium oxide-containing resin.

[0167]

The resin film layer 31B at the wall sections 24B of the top sheet 2B has a plurality of openings 34B arranged in the direction extending along each of the protrusions 21B (lengthwise direction) . The openings 34B are holes running through the resin film layer 31B, and body fluid of the wearer is absorbed through the openings 34B into the fiber aggregate layer 32B, and subsequently absorbed into the absorbent body. The open area of each opening 34B is preferably at least 0.0005 mm² and no greater than

1.5 mm², and more preferably at least 0.01 mm² and no greater than 0.5 mm². If the open area of each of the openings 34B is smaller than 0.0005 mm², body fluid of the wearer may not pass through the openings 34B, and if the open area of each of the openings 34B is greater than 1.5 mm², body fluid that has been absorbed into the absorbent body may flow back through the openings 34B of the resin film layer 31B, or the proportion of area of the sections of the resin film layer 31B other than the openings 34B may be reduced, thus reducing the concealing property of the top sheet 2B. Also, if the open area of each of the openings 34B of the resin film layer 31B is greater than

1.5 mm², the strength of the top sheet 2B may be

excessively low.

[0168]

The proportion of the total open area of all

openings 34B with respect to the entire area of the resin film layer 31B, i.e., the open area ratio of the resin film layer 31B, is preferably at least 1% and no greater than 10%. If the open area ratio of the resin film layer 31B is lower than 1%, the permeability of the top sheet 2B for body fluid may be impaired, and if the open area ratio of the resin film layer 31B is higher than 10%, body fluid that has been absorbed into the absorbent body may flow back through the openings 34B of the resin film layer 31B, or the proportion of area of the sections of the resin film layer 31B other than the openings 34B may be reduced, thus reducing the concealing property of the top sheet 2B. Also, if the open area ratio of the resin film layer 31B is higher than 10%, the strength of the top sheet 2B may be excessively low.

[0169]

The top sheet is preferably subjected to

hydrophilicizing treatment, by being coated or mixed with a hydrophilic agent. If the original material is

hydrophilic, since it is subseguently coated with a lipophilic modifying agent having an IOB of about 0.00-

0.60 and high organicity, there will be created sparsely dispersed lipophilic regions and hydrophilic regions. This presumably allows consistent absorption performance to be exhibited for menstrual blood which consists of hydrophilic components (blood plasma, etc.) and

lipophilic components (blood cells, etc.).

[0170]

The fiber aggregate layer 32B includes a sheet or nonwoven fabric of hydrophilic fiber aggregates. A preferred nonwoven fabric for use as the fiber aggregate layer 32B, for example, a tissue. "Tissue" is thin paper with a basis weight of at least 10 g/m² and no greater than 20 g/m², composed mainly of Kraft pulp or rayon for wet strength. The thickness of the fiber aggregate layer 32B is preferably at least 0.1 mm and no greater than 0.5 mm. Even if the resin film layer 31B is not hydrophilic, the fiber aggregate layer 32B can impart hydrophilicity to the top sheet 2B. The fiber aggregate layer 32B can also impart softness to the top sheet 2B. A tissue may be used for the fiber aggregate layer 32B, as tissue sheets are less expensive than other sheets and nonwoven fabrics and are abundantly available on the market.

While the strength of tissue paper is generally low, if it is used together with the resin film layer 31B it will be possible to use the tissue as the fiber aggregate layer 32B of the top sheet 2B. In addition, since a tissue easily has its matrix disrupted, this will

facilitate formation of openings 34 in the resin film layer 31B in the gear stretching step, as described hereunder .

[0171]

The lubricant layer 33B is the same as the lubricant layer 27A formed on the surface of the top sheet 2A of the absorbent article of the first embodiment, and explanation of the lubricant layer 33B will therefore be omitted.

[0172]

A method for producing a top sheet according to the second embodiment of the invention will now be explained with reference to Fig. 11. Fig. 11 is an illustration of a top sheet production apparatus 100B to be used in a method for producing a top sheet 2B according to the second embodiment of the invention. The top sheet production apparatus 100B comprises a stretching gear roll 130 and a lubricant coating sprayer 140. The method for producing the top sheet 2B includes a step of

preparing a composite sheet comprising a resin film layer and a fiber aggregate layer, a gear stretching step, and a lubricant coating step.

[0173]

In the step of preparing a composite sheet

comprising a resin film layer and a fiber aggregate layer, a composite sheet 103B fed from a composite sheet roll (not shown) is supplied to the stretching gear roll

130. The composite sheet 103B is produced, for example, by extrusion laminating a resin into a fiber sheet such as a tissue sheet (tissue that has been formed into a sheet), to form a resin film layer on the fiber sheet.

[0174]

In the gear stretching step, the composite sheet 103 is passed through a stretching gear roll 130 to form protrusions in the composite sheet 103, and form openings in the resin film layer of the composite sheet. The stretching gear roll used in this gear stretching step is the same as the gear stretching roll 130 used in the method for producing a top sheet for an absorbent article according to the first embodiment, and explanation of the gear stretching roll will therefore be omitted here.

[0175]

When the composite sheet 103B passes through the stretching gear roll 130, the composite sheet 103B is formed in an essentially undulating manner, and a

plurality of protrusions extending in the machine

direction and arranged side-by-side in the cross-machine direction are formed in the composite sheet 103B.

[0176] The principle by which openings are formed in the resin film layer of the composite sheet 103B after the composite sheet 103B has passed through the stretching gear roll 130 will now be explained with reference to Fig. 12. The explanation of this principle is not intended to limit the scope of the invention.

[0177]

The composite sheet 103B is stretched at the

sections 105B where the gear teeth 133 of the upper gear roll 131 and the gear teeth 134 of the lower gear roll

132 are engaged.

[0178]

The fiber aggregate layer easily has its matrix disrupted, and the tensile strength of the fiber

aggregate layer is lower than the tensile strength of the resin film layer. If the composite sheet 103B is drawn until the fiber aggregate layer undergoes matrix

disruption, the integrated resin film layer at the matrix disrupted sections of the tissue layer are disrupted together with it, and openings are formed in the resin film layer.

[0179]

More specifically, the surface of the fiber

aggregate layer has low smoothness, and small concavo- convex sections are formed on the surface of the fiber aggregate layer. Consequently, areas with strong

adhesive force and weak adhesive force with the fiber aggregate layer are created in the resin film layer.

Since the resin film layer at the areas with strong adhesive force with the fiber aggregate layer become integrated with the fiber aggregate layer when the composite sheet 103B is stretched until the fiber

aggregate layer undergoes matrix disruption, the resin film layer is disrupted together with the matrix

disruption of the fiber aggregate layer, thus forming openings. However, the resin film layer at the areas of weak adhesive force with the fiber aggregate layer lose their adhesion with the fiber aggregate layer when the composite sheet 103B is stretched until the fiber

aggregate layer undergoes matrix disruption, and it therefore becomes separated from the fiber aggregate layer. As a result, the resin film layer at the areas of weak adhesive force with the fiber aggregate layer are not disrupted together with the matrix disruption of the fiber aggregate layer. Consequently, openings are not formed in the resin film layer at the areas of weak adhesive force with the fiber aggregate layer. Since concavo-convexities are formed in an irregular manner in the surface of the fiber aggregate layer, openings of irregular size are formed in the resin film layer.

[0180]

The composite sheet 103B is not significantly stretched at the sections 106B where the gear teeth 133 of the upper gear roll 131 and the gear teeth 134 of the lower gear roll 132 are not engaged. Consequently, even when the composite sheet 103B passes through the

stretching gear roll 130, openings are not formed at the sections 106B of the composite sheet 103B where the gear teeth 133 of the upper gear roll 131 and the gear teeth 134 of the lower gear roll 132 are not engaged.

[0181]

The sections 106B of the composite sheet 103B where the gear teeth 133 of the upper gear roll 131 and the gear teeth 134 of the lower gear roll 132 are not engaged correspond to the top sections 23B of the protrusions 21B and bottom sections 22B in the top sheet 2B (see Fig. 10) . The sections 105B of the composite sheet 103B where the gear teeth 133 of the upper gear roll 131 and the gear teeth 134 of the lower gear roll 132 are engaged correspond to the wall sections 24B of the protrusions 21B in the top sheet 2B (see Fig. 10) . Consequently, no openings 34B are present in the top sections 23B of the protrusions 21B and bottom sections 22B in the top sheet 2B, while openings 34B are formed in the wall sections 24B of the protrusions 21B in the top sheet 2B.

[0182]

Fig. 13 shows a set of photomicrographs of the skin facing side of a top sheet where openings have been formed in the resin film layer. Fig. 13(a) is a

photomicrograph of the skin facing side of the top sheet, showing a plurality of openings arranged along the direction of the protrusions. Fig. 13(b) is also a photomicrograph, at a large scale than Fig. 13(a), of the skin facing side of a top sheet, showing the wall

sections of protrusions with openings. Fig. 13(c) is also a photomicrograph, at an even larger scale than Fig. 13(b), of the skin facing side of a top sheet, showing openings on the film resin layer.

[0183]

Fig. 14 shows a pair of photomicrographs of the non- skin facing side of a top sheet where openings have been formed in the resin film layer. Fig. 14(a) is a

photomicrograph of the non-skin facing side of the top sheet, showing the matrix-disrupted fiber aggregate layer and the resin film layer in which openings have been formed. Fig. 14 (b) is a photomicrograph, at a larger scale than Fig. 14(a), of the non-skin facing side of the top sheet, showing the fibers of the matrix-disrupted fiber aggregate layer covering openings of the resin film layer .

[0184]

In the lubricant coating step, the lubricant coating sprayer 140 is used to coat the lubricant 141 on the resin film layer side of the gear stretched composite sheet 104B, to form a lubricant layer on the composite sheet 104B. The coating amount of the lubricant is the same as the coating amount of the lubricant for the method for producing a top sheet of an absorbent article according to the first embodiment.

[0185]

In the method for producing the top sheet 2B described above, instead of a step of preparing a

composite sheet comprising a resin film layer and a fiber aggregate layer, there may be provided a step of

preparing a fiber sheet, and a step of fabricating a composite sheet by laminating a resin with the fiber sheet to form a resin film layer on the fiber sheet.

[0186]

The absorbent article of the first embodiment and the absorbent article of the second embodiment may incorporate the following modifications.

(1) So long as at least a portion of at least the skin facing side surface of the top sheet is formed of a resin film having a lubricant layer formed on the skin facing side surface, it is not necessary for the entire top sheet to be a resin film 2A having a lubricant layer

27A formed on the skin facing side surface, as with the absorbent article of the first embodiment, or for the entire surface of the skin facing side of the top sheet 2B to be a resin film 31B having a lubricant layer 33B formed on the skin facing side surface, as with the absorbent article of the second embodiment. For example, in the top sheet of the absorbent article, a lubricant layer 33C may be formed on the skin facing side surface of the resin film layer 31C that has been formed in a striped pattern of a plurality of discrete stripes on the skin facing side surface of a nonwoven fabric or tissue 32C, as in the top sheet 2C shown in Fig. 15. Fig. 15 is a magnified schematic perspective view of a portion of a top sheet 2C. In this case, the lubricant layer 33C is present between the body fluid of the wearer and the resin film layer 31C, and therefore wipeability of the body fluid is satisfactory. Body fluid that has adhered onto the nonwoven fabric or tissue 32C is absorbed through the nonwoven fabric or tissue 32C into the absorbent body, and therefore does not need to be wiped off.

[0187] The width of the striped resin film layer 31C may be, for example, 0.05-3 mm, and is preferably 0.1-1 mm. The distance between adjacent resin film layers 31C may be, for example, 0.05-3 mm, and is preferably 0.1-1 mm. The striped resin film layer 31C is formed on a base · material such as a nonwoven fabric 32C by, for example, continuously coating a resin composed mainly of

polyethylene onto the nonwoven fabric or the like in a striped pattern, and then applying pressure in the thickness direction with a nip roll.

[0188]

lubricant layer 27D such as shown in Fig. 16(b) may also be formed on the surface of the top sheet 2D of the resin film described in PTL 1, shown in Fig. 16(a). Figs. 16(a) and (b) are magnified schematic perspective views of a portion of a top sheet 2D. Piliform fibrils 21D are formed on the surface of the top sheet 2D

described in PTL 1 (i.e., Japanese Patent Public

Inspection No. 2006-515539 which is incorporated by reference herein in its entirety) . Since body fluid thus remains between the plurality of fibrils 21D, it is difficult to wipe off body fluid from the top sheet 2D. Furthermore, the piliform fibrils 21D can potentially rupture toilet paper or the like that is used to wipe off body fluid. However, forming a lubricant layer 27D on the surface of the top sheet 2D can inhibit residue of body fluid between the plurality of fibrils 21D, and allow body fluid adhering to the top sheet 2D to be easily wiped off. Moreover, because body fluid can be easily wiped off, and it is therefore unnecessary to rub the top sheet 2D with toilet paper or the like, it is thus possible to avoid rupturing toilet paper used for wiping off of body fluid.

[0189]

Incidentally, the lubricant layer 27E may be formed on the surface of a top sheet 2E without piliform fibrils formed on the surface of the top sheet of the resin film described in PTL 1 (see Fig. 17), i.e., on the surface of a top sheet 2E on which only openings 25E have been formed. Fig. 17 is a magnified schematic perspective view of a portion of such a top sheet 2E.

[0190]

(2) The top sheet and absorbent body do not need to be bonded at least in the area for facing the body fluid excretion hole of the wearer. In this case, at least the area of the top sheet for facing the body fluid excretion hole of the wearer is formed of a resin film having a lubricant layer formed on the skin facing side surface. This can facilitate deformation of the top sheet, to allow even easier wiping of body fluid such as menstrual blood that remains on the surface of the top sheet.

Especially when the top sheet is formed so that the cross-section is an essentially undulating shape, the. top sheet is even more easily flattened as the essentially undulating shape of the top sheet is deformed by pressure applied to the surface of the top sheet when body fluid is wiped off by the wearer using toilet paper or the like. This further facilitates wiping of body fluid that has adhered to the surface of the top sheet.

[Examples]

[0191]

Some examples of the present invention will now be explained in greater detail by examples, with the

understanding that these examples are in no way

limitation on the invention.

[0192]

(Wipeability)

The wipeability of the top sheets in the examples and comparative examples was measured in the following manner.

[0193]

(1) A sample was placed on a stack of 3 filter paper sheets (100 mm x 100 mm) . The 3 stacked filter paper sheets correspond to an absorbent body. (2) A pipette with an inner diameter of 1.8 mm was used to vertically drop 0.1 mg of highly viscous

artificial menstrual blood onto the sample from a height of 10 mm above the sample, at a rate of 100 g/min. The composition of the highly viscous artificial menstrual blood used was the following.

Composition of highly viscous artificial menstrual blood 97 wt% of 0.9% physiological saline

3 wt% tamarind gum (trade name: Glyloid 6C,

purchased from DSP Gokyo Food & Chemical Co., Ltd.)

Trace food coloring: Red #102

(3) After dropping, the mixture was allowed to stand for 1 minute .

(4) After folding toilet paper 6 times to a size of 110 mm x 60 mm, the folded toilet paper was wrapped around the middle finger of the hand. The toilet paper was moved 30 mm on the surface of the sample at a

pressure of 100-150 g/cm², to wipe off the dropped highly viscous artificial menstrual blood with the toilet paper.

(5) The mass of the sample after wiping was

measured, and the mass of the sample before dropping the highly viscous artificial menstrual blood was subtracted from the measured mass to calculate the residual amount of highly viscous artificial menstrual blood remaining on the sample.

[0194]

Production methods used in the examples and

comparative examples will now be explained.

[0195]

(Example 1)

Holes were formed in a resin film comprising 97 wt% polyethylene and 3 wt% titanium oxide, by perforation. The basis weight of the hole-formed resin film was 22 g/m², the effective opening diameter was 0.5-0.8 mm, and the effective open area ratio was 18%. Also, the surface of the resin film was coated with triglyceride (trade name: PANACET 810s (IOB: 0.32, melting point: -5°C, water solubility: <0.05 g, purchased from NOF Corp.) to a coating amount of 5 g/m².

[0196]

(Example 2)

A top sheet was fabricated for Example 2 by the method for producing a top sheet according to the first embodiment. The conditions for Example 2 were as follows.

Composition of resin film: 97 wt% polyethylene, 3 wt% titanium oxide

Pitch of lattice-like convexities on roulette roll: 0.4 mm

Gear tooth width: 0.5 mm

Gear tooth height: 1.5 mm

Distance between adjacent gear teeth: 1.0 mm

Gap between upper gear roll gear teeth and lower gear roll gear teeth: 0.25 mm

Stretching gear roll engagement depth: 1.1 mm

Lubricant: Triglyceride (trade name: PANACET 810s (IOB: 0.32, melting point -5°C, water solubility: <0.05 g, purchased from NOF Corp. ) .

Coating amount: 5 g/m²

[0197]

The form in Example 2 was as follows.

Protrusion height: 0.05 mm

Distance between centers of adjacent protrusions in widthwise direction (protrusion pitch): 2.5 mm

Opening diameter: 0.1-0.6 mm

Effective open area ratio: 10%

[0198]

(Comparative Example 1)

The fabrication method in Comparative Example 1 was the same as the method of Example 1, except that no triglyceride was coated.

[0199]

(Comparative Example 2)

The fabrication method for Comparative Example 2 was the same as the method for Example 2, except that no triglyceride was coated.

[0200]

Fig. 18 shows photomicrographs taken of the surfaces for Examples 1 and 2 and Comparative Examples 1 and 2.

Fig. 18(a) is a photomicrograph taken of the surface for Example 1, Fig. 18(b) is a photomicrograph taken of the surface for Example 2, Fig. 18(c) is a photomicrograph taken of the surface for Comparative Example 1 and Fig. 18 (d) is a photomicrograph taken of the surface for

Comparative Example 2.

[0201]

The results of a wiping test for the examples and comparative examples are shown below.

[0202]

Fig. 19 shows the condition of surfaces for the examples and comparative examples, after dropping highly viscous artificial menstrual blood and allowing it to stand for 1 minute for the examples and comparative examples. Fig. 19(a) is a photograph showing the

condition of the surface for Example 1, Fig. 19(b) is a photograph showing the condition of the surface for

Example 2, Fig. 19(c) is a photograph showing the

condition of the surface for Comparative Example 1, and Fig. 19(d) is a photograph showing the condition of the surface for Comparative Example 2.

[0203]

Fig. 20 shows the condition of surfaces of toilet paper after wiping highly viscous artificial menstrual blood for examples and comparative examples. Fig. 20(a) is a photograph showing the condition of the surface of toilet paper after wiping highly viscous artificial menstrual blood for Example 1, Fig. 20(b) is a photograph showing the condition of the surface of toilet paper after wiping highly viscous artificial menstrual blood for Example 2, Fig. 20(c) is a photograph showing the condition of the surface of toilet paper after wiping highly viscous artificial menstrual blood for Comparative Example 1, and Fig. 20(d) is a photograph showing the condition of the surface of toilet paper after wiping highly viscous artificial menstrual blood for Comparative Example 2.

[0204]

Fig. 21 shows the condition of surfaces for examples and comparative examples after wiping highly viscous artificial menstrual blood using toilet paper. Fig.

21(a) is a photograph showing the condition of the surface for Example 1, Fig. 21(b) is a photograph showing the condition of the surface for Example 2, Fig. 21(c) is a photograph showing the condition of the surface for Comparative Example 1, and Fig. 21(d) is a photograph showing the condition of the surface for Comparative

Example 2.

[0205]

From the photographs in Fig. 21 it is seen that less highly viscous artificial menstrual blood remained on the surface of Example 1 compared to the surface of

Comparative Example 1, and that less highly viscous artificial menstrual blood remained on the surface of Example 2 compared to the surface of Comparative Example 2. This demonstrates that coating a lubricant on the top sheet allows cleaner wiping of highly viscous artificial menstrual blood that has adhered to the top sheet.

[0206]

The amount of residue of highly viscous artificial menstrual blood in Example 1 after wiping highly viscous artificial menstrual blood using toilet paper was 0.01 g, the amount of residue of highly viscous artificial menstrual blood in Example 2 was 0.00 g, the amount of residue of highly viscous artificial menstrual blood in Comparative Example 1 was 0.03 g, and the amount of residue of highly viscous artificial menstrual blood in

Comparative Example 2 was 0.02 g. This also demonstrates that coating a lubricant on the top sheet allows cleaner wiping of highly viscous artificial menstrual blood that has adhered to the top sheet.

[0207]

Less highly viscous artificial menstrual blood remained after wiping in Example 2 than in Example 1.

This is attributed to the fact that pressure applied to the surface of Example 2 when highly viscous artificial menstrual blood was wiped with toilet paper caused deformation of the protrusions of Example 2 and

flattening of the surface of Example 2, thus facilitating wiping of the highly viscous artificial menstrual blood that has adhered to the surface.

[0208]

(Mechanism of lowering viscosity and surface tension of blood by blood modifying agent)

In the following examples, the blood modifying agent was confirmed to have a mechanism of lowering the

viscosity and surface tension of blood.

[0209]

[Example 1]

[Evaluation of rewetting rate and absorbent body

migration rate]

[Data of blood modifying agents]

A commercially available sanitary napkin was

prepared. The sanitary napkin was formed from a top sheet, formed of a hydrophilic agent-treated air-through nonwoven fabric (composite fiber composed of polyester and polyethylene terephthalate, basis weight: 35 g/m²) , a second sheet, formed of an air-through nonwoven fabric (composite fiber composed of polyester and polyethylene terephthalate, basis weight: 30 g/m²), an absorbent body comprising pulp (basis weight: 150-450 g/m², increased at the center section) , an acrylic super-absorbent polymer (basis weight: 15 g/m²) and tissue as a core wrap, a water-repellent agent-treated side sheet, and a back sheet composed of a polyethylene film.

[0210] The blood modifying agents used for the experiment are listed below.

[ (ai) Ester of a chain hydrocarbon tetraol and at least one fatty acid]

· UNISTAR H-408BRS, product of NOF Corp.

Tetrapentaerythritol 2-ethylhexanoate, weight- average molecular weight: approximately 640

^• UNISTAR H-2408BRS-22, product of NOF Corp.

Mixture of tetrapentaerythritol 2-ethylhexanoate and di-neopentyl 2-ethylhexanoate glycol (58:42, mass ratio), weight-average molecular weight: approximately 520

[0211]

[ (a₂) Ester of a chain hydrocarbon triol and at least one fatty acid]

· Cetiol SB45DEO, Cognis Japan

Glycerin and fatty acid triester, with oleic acid or stearylic acid as the fatty acid.

^• SOY42, product of NOF Corp.

Glycerin and fatty acid triester with C₁₄ fatty

acid:Ci6 fatty acid:Ci₈ fatty acid:C2o fatty acid

(including both saturated fatty acids and unsaturated fatty acids) at a mass ratio of about 0.2:11:88:0.8, weight-average molecular weight: 880

[0212]

· Tri-C2L oil fatty acid glyceride, product of NOF Corp.

Glycerin and fatty acid triester with Cg fatty acid:Cio fatty acid:Ci₂ fatty acid at a mass ratio of about 37:7:56, weight-average molecular weight: approximately 570

· Tri-CL oil fatty acid glyceride, product of NOF Corp.

Glycerin and fatty acid triester with Cs fatty

acid:Ci2 fatty acid at a mass ratio of about 44:56, weight-average molecular weight: approximately 570

[0213]

· PANACET 810s, product of NOF Corp.

Glycerin and fatty acid triester with Cg fatty acid:Cio fatty acid at a mass ratio of about 85:15, weight-average molecular weight: approximately 480

• PANACET 800, product of NOF Corp.

Glycerin and fatty acid triester with octanoic acid (Ce) as the entire fatty acid portion, weight-average molecular weight: approximately 470

[0214]

• PANACET 800B, product of NOF Corp.

Glycerin and fatty acid triester with 2- ethylhexanoic acid (Cs) as the entire fatty acid portion, weight-average molecular weight: approximately 470

^• NA36, product Of NOF Corp.

Glycerin and fatty acid triester with Ci₆ fatty

acid:Ci8 fatty acid:C₂o fatty acid (including both

saturated fatty acids and unsaturated fatty acids) at a mass ratio of about 5:92:3, weight-average molecular weight: approximately 880

[0215]

^• Tri-coconut fatty acid glyceride, product of NOF Corp.

Glycerin and fatty acid triester with Cs fatty acid:Cio fatty acid:Ci2 fatty acid:Ci4 fatty acid:Ci6 fatty acid (including both saturated fatty acids and

unsaturated fatty acids) at a mass ratio of about

4:8:60:25:3, weight-average molecular weight: 670

[0216]

^• Caprylic acid diglyceride, product of NOF Corp.

Glycerin and fatty acid diester with octanoic acid as the fatty acid, weight-average molecular weight:

approximately 340

[0217]

[ (a3) Ester of a chain hydrocarbon diol and at least one fatty acid]

^• CO POL BL, product of NOF Corp.

Dodecanoic acid (C12) monoester of butylene glycol, weight-average molecular weight: approximately 270 ^• COMPOL BS, product of NOF Corp.

Octadecanoic acid (Cis) monoester of butylene glycol, weight-average molecular weight: approximately 350 • U ISTAR H-208BRS, product of NOF Corp.

Neopentylglycol di-2-ethylhexanoate, weight-average molecular weight: approximately 360.

[0218]

[ (c₂) Ester of a chain hydrocarbon tricarboxylic acid, hydroxy acid, alkoxy acid or oxoacid with 3 carboxyl groups, and at least one aliphatic monohydric alcohol]

^• Tributyl O-acetylcitrate, product of Tokyo Kasei Kogyo Co., Ltd.

Weight-average molecular weight: approximately 400

[0219]

t (c₃) Ester of a chain hydrocarbon dicarboxylic acid, hydroxy acid, alkoxy acid or oxoacid with 2 carboxyl groups, and at least one aliphatic monohydric alcohol] · Dioctyl adipate, product of Wako Pure Chemical

Industries, Ltd.

Weight-average molecular weight: approximately 380

[0220]

[ (d₃) Ester of a fatty acid and an aliphatic monohydric alcohol]

^• ELECTOL WE20, product of NOF Corp.

Ester of dodecanoic acid (Ci₂) and dodecyl alcohol (C12) , weight-average molecular weight: approximately 360 ^• ELECTOL WE40, product of NOF Corp.

Ester of tetradecanoic acid (C14) and dodecyl alcohol

(C12) , weight-average molecular weight: approximately 390

[0221]

[ (ei) Polyoxy C₂-C6 alkylene glycol]

^• UNIOL D-1000, product of NOF Corp.

Polypropylene glycol, weight-average molecular weight: approximately 1,000

^• UNIOL D-1200, product of NOF Corp.

Polypropylene glycol, weight-average molecular weight: approximately 1,160

· UNIOL D-3000, product of NOF Corp.

Polypropylene glycol, weight-average molecular weight: approximately 3,000 [0222]

^• UNIOL D-4000, product of NOF Corp.

Polypropylene glycol, weight-average molecular weight: approximately 4,000

^• UNIOL PB500, product of NOF Corp.

Polybutylene glycol, weight-average molecular weight: approximately 500

^• UNIOL PB700, product of NOF Corp.

Polyoxybutylenepolyoxypropylene glycol, weight- average molecular weight: approximately 700

[0223]

^• UNIOL PB1000R, product of NOF Corp.

Polybutylene glycol, weight-average molecular weight: approximately 1,000

[ (e2) Ester of a polyoxy C2-C6 alkylene glycol and at least one fatty acid]

^• ILBRITE cp9, product of NOF Corp.

Polybutylene glycol compound with OH groups at both ends esterified by hexadecanoic acid (Ci₆) , weight-average molecular weight: approximately 1,150

[ (e₃) Ether of polyoxy C2-C6 alkylene glycol and at least one fatty acid]

^• UNILUBE MS-70K, product of NOF Corp.

Stearyl ether of polypropylene glycol, approximately 15 repeating units, weight-average molecular weight:

approximately 1,140

[0224]

[ (e₅) Ether of a polyoxy C₂-C6 alkylene glycol with chain hydrocarbon tetraol, chain hydrocarbon triol or chain hydrocarbon diol]

^• UNILUBE 5TP-300KB

Polyoxyethylenepolyoxypropylene pentaerythritol ether, produced by addition of 5 mol of ethylene oxide and 65 mol of propylene oxide to 1 mol of

pentaerythritol, weight-average molecular weight: 4,130

[0225]

^• UNIOL TG-3000, product of NOF Corp. Glyceryl ether of polypropylene glycol,

approximately 16 repeating units, weight-average

molecular weight: approximately 3,000

• UNIOL TG-4000, product of NOF Corp.

Glyceryl ether of polypropylene glycol,

approximately 16 repeating units, weight-average

molecular weight: approximately 4,000

[0226]

[ (fx) Chain alkane]

· PARLEAM 6, product of NOF Corp.

Branched hydrocarbon, produced by copolymerization of liquid isoparaffin, isobutene and n-butene followed by hydrogen addition, polymerization degree: approximately 5-10, weight-average molecular weight: approximately 330

[0227]

[Other components]

• NA50, product of NOF Corp.

Glycerin and fatty acid triester obtained by

addition of hydrogen to NA36 for reduced proportion of double bonds from unsaturated fatty acid starting

material, weight-average molecular weight: approximately 880

• (Caprylic acid/capric acid) monoglyceride, product of NOF Corp.

Glycerin and fatty acid monoester, with octanoic acid (Cg) and decanoic acid (Cio) at a mass ratio of about 85:15, weight-average molecular weight: approximately 220

• Monomuls 90-L2 lauric acid monoglyceride, product of Cognis Japan

[0228]

^• Isopropyl citrate, product of Tokyo Kasei Kogyo Co., Ltd.

Weight-average molecular weight: approximately 230

• Diisostearyl malate

Weight-average molecular weight: approximately 640

• UNIOL D-400,^" product of NOF Corp.

Polypropylene glycol, weight-average molecular weight: approximately 400

[0229]

^• PEG1500, product of NOF Corp.

Polyethylene glycol, weight-average molecular weight: approximately 1,500-1,600

^• NONION S-6, product of NOF Corp.

Polyoxyethylene monostearate, approximately 7 repeating units, weight-average molecular weight:

approximately 880

^• ILBRITE s753, product of NOF Corp.

Polyoxyethylenepolyoxypropylene polyoxybutylene glycerin, weight-average molecular weight: approximately 960

[0230]

^• UNIOL TG-330, product of NOF Corp.

Glyceryl ether of polypropylene glycol,

approximately 6 repeating units, weight-average molecula weight: approximately 330

^• UNIOL TG-1000, product of NOF Corp.

Glyceryl ether of polypropylene glycol,

approximately 16 repeating units, weight-average

molecular weight: approximately 1,000

[0231]

^• UNILUBE DGP-700, product of NOF Corp.

Diglyceryl ether of polypropylene glycol,

approximately 9 repeating units, weight-average molecula weight: approximately 700

^• UNIOX HC60, product of NOF Corp.

Polyoxyethylene hydrogenated castor oil, weight- average molecular weight: approximately 3,570

■ Vaseline, product of Cognis Japan

Petroleum-derived hydrocarbon, semi-solid

[0232]

The IOBs, melting points and water solubilities of the samples are shown in Table 2.

The water solubility was measured by the method described above, and samples that dissolved 24 hours after addition of 20.0 g to 100 g of desalted water were evaluated as "20 g<", and samples of which 0.05 g

dissolved in 100 g of desalted water but 1.00 g did not dissolve were evaluated as 0.05-1.00 g.

For the melting point, "<45" indicates a melting point of below 45°C.

[0233]

The skin contact surface of the top sheet of the sanitary napkin was coated with the aforementioned blood modifying agent. Each blood modifying agent was used directly, when the blood modifying agent was liquid at room temperature, or when the bipod modifying agent was solid at room temperature it was heated to its melting point of +20°C, and a control seam HMA gun was used for atomization of the blood modifying agent and coating onto the entire skin contact surface of the top sheet to a basis weight of about 5 g/m².

[0234]

Fig. 22 is an electron micrograph of the skin contact surface of a top sheet in a sanitary napkin

(No.2-5) wherein the top sheet comprises tri-C2L oil fatty acid glycerides . As clearly seen in Fig. 22, the tri-C2L oil fatty acid glycerides are present on the fiber surfaces as fine particulates.

In accordance with the above procedures, the

rewetting rate and absorber migration rate were measured. The results are shown below in Table 2.

[0235]

[Test methods]

An acrylic board with an opened hole (200 mm x 100 mm, 125 g, with a 40 mm x 10 mm hole opened at the center) was placed on a top sheet comprising each blood modifying agent, and 3 g of horse EDTA blood at 37±1°C

(obtained by adding appropriate amount of

ethylenediaminetetraacetic acid (hereunder, "EDTA") to horse blood to prevent coagulation) was dropped through the hole using a pipette (once) , and after 1 minute, 3 g of horse EDTA blood at 37±1°C was again added dropwise through the acrylic board hole with a pipette (twice) .

[0236]

After the second dropping of blood, the acrylic board was immediately removed and 10 sheets of filter paper (Advantec Toyo Kaisha, Ltd, Qualitative Filter Paper No.2, 50 mm x 35 mm) were placed on the location where the blood had been dropped, and then a weight was placed thereover to a pressure of 30 g/cm². After 1 minute, the filter paper was removed and the "rewetting rate" was calculated by the following formula.

Rewetting rate (%)

= 100 x (filter paper mass after test - initial filter paper mass)/6

[0237]

In addition to the rewetting rate evaluation, the "absorbent body migration rate" was also measured as the time until migration of blood from the top sheet to the absorbent body after the second dropping of blood. The absorbent body migration rate is the time from

introducing the blood onto the top sheet, until the redness of the blood could be seen on the surface and in the interior of the top sheet.

The results for the rewetting rate and absorbent body migration rate are shown below in Table 2.

[0238]

Then the whiteness of the skin contact surface of the top sheet after the absorbent body migration rate test was visually evaluated on the following scale.

VG (Very Good) : Virtually no redness of blood remaining, and no clear delineation between areas with and without blood.

G (Good) : Slight redness of blood remaining, but difficult to delineate between areas with and without blood. F (Fair) : Slight redness of blood remaining, with blood discernible.

P (Poor): Redness of blood completely remaini The results are summarized below in Table 2.

[0239]

Table 2

[0240]

Table 2 (cont . )

[0241]

In the absence of a blood modifying agent, the rewetting rate was 22.7% and the absorbent body migration rate was greater than 60 seconds, but the glycerin and fatty acid triesters all produced rewetting rates of no greater than 7.0% and absorbent body migration rates of no longer than 8 seconds, and therefore significantly improved the absorption performance. Of the glycerin and fatty acid triesters, however, no great improvement in absorption performance was seen with NA50 which had a melting point of above 45°C.

[0242]

Similarly, the absorption performance was also significantly improved with blood modifying agents having an IOB of about 0.00-0.60, a melting point of no higher than about 45°C and a water solubility of no greater than about 0.05 g in 100 g of water at 25°C. Rewetting rates of no greater than 7.9% and absorbent body migration rates of no longer than 15 seconds were achieved.

[0243]

Next, several volunteer subjects were asked to wear sanitary napkins Nos. (2-1) - (2-47) , and the obtained responses indicated that with the sanitary napkins comprising blood modifying agents Nos. (2-1) - (2-32) , the top sheets had no sticky feel and the top sheets were smooth, even after absorption of menstrual blood

[0244]

Also, with sanitary napkins Nos. (2-1) - (2-32) , and particularly with sanitary napkins that comprised blood modifying agents Nos. (2-1) - (2-11) , (2-15) - (2-19) and (2- 32), the skin contact surfaces of the top sheets after absorption of menstrual blood had not been reddened by the blood and the unpleasantness was minimal.

[0245]

[Example 2]

The rewetting rate was evaluated for blood from different animals in accordance with the above

procedures. The following blood was used for the test. [Animal species]

( 1 ) Human

(2) Horse

(3) Sheep

[0246]

[Types of blood]

• Defibrinated blood: blood sampled and agitated together with glass beads in an Erlenmeyer flask for approximately

5 minutes.

• EDTA blood: 65 mL of venous blood with addition of 0.5 mL of a 12% EDTA-2K isotonic sodium chloride solution.

[0247]

[Fractionation]

Serum or blood plasma: Supernatant obtained after centrifugation of defibrinated blood or EDTA blood for 10 minutes at room temperature at about 1900 G.

Blood cells: Obtained by removing the serum from the blood, washing twice with phosphate buffered saline

(PBS) , and adding phosphate buffered saline to the removed serum portion.

[0248]

An absorbent article was produced in the same manner as Example 2, except that the tri-C2L oil fatty acid glyceride was coated at a basis weight of about 5 g/m², and the rewetting rate of each of the aforementioned blood samples was evaluated. Measurement was performed 3 times for each blood sample, and the average value was recorded.

The results are shown in Table 3 below.

[0249] Table 3

[0250]

The same trend was seen with human and sheep blood as with the horse EDTA blood, as obtained in Example 2.

A similar trend was also observed with defibrinated blood and EDTA blood.

[0251]

[Example 3]

[Evaluation of blood retention]

The blood retention was evaluated for a top sheet comprising a blood modifying agent and a top sheet comprising no blood modifying agent.

[0252]

[Test methods]

(1) A tri-C2L oil fatty acid glyceride was atomized on the skin contact surface of a top sheet formed from an air-through nonwoven fabric (composite fiber composed of polyester and polyethylene terephthalate, basis weight: 35 g/m²) , using a control seam HMA gun, for coating to a basis weight of about 5 g/m². For comparison, there was also prepared a sheet without coating with the tri-C2L oil fatty acid glyceride. Next, both the tri-C2L oil fatty acid glyceride-coated top sheet and the non-coated top sheet were cut to a size of 0.2 g, and the mass (a) of the cell strainer + top sheet was precisely measured.

[0253]

(2) After adding about 2 mL of horse EDTA blood from the skin contact surface side, it was allowed to stand for 1 minute.

(3) The cell strainer was set in a centrifuge tube, and subjected to spin-down to remove the excess horse EDTA blood.

(4) The mass (b) of the top sheet containing the cell strainer + horse EDTA blood was measured.

(5) The initial absorption (g) per 1 g of top sheet was calculated by the following formula.

Initial absorption = [mass (b) - mass (a)]/0.2

(6) The cell strainer was again set in the

centrifuge tube and centrifuged at room temperature for 1 minute at approximately 1,200 G.

[0254]

(7) The mass (c) of the top sheet containing the cell strainer + horse EDTA blood was measured.

(8) The post-test absorption (g) per 1 g of top sheet was calculated by the following formula.

Post-test absorption = [mass (c) - mass (a)]/0.2

(9) The blood retention (%) was calculated according to the following formula.

Blood retention (%) = 100 x post-test

absorption/initial absorption

The measurement was conducted 3 times, and the average value was recorded.

The results are shown in Table 4 below.

[0255] Table 4

[0256]

The top sheets comprising blood modifying agents had low blood retentions, suggesting that blood rapidly migrated into the absorbent body after absorption.

[0257]

[Example 4]

[Viscosity of blood containing blood modifying agent]

The viscosity of the blood modifying agent- containing blood was measured using a Rheometric

Expansion System ARES (Rheometric Scientific, Inc.).

After adding 2 massl of PANACET 810s to horse

defibrinated blood, the mixture was gently agitated to form a sample, the sample was placed on a 50 mm-diameter parallel plate, with a gap of 100 μπι, and the viscosity was measured at 37±0.5°C. The sample was not subjected to a uniform shear rate due to the parallel plate, but the average shear rate indicated by the device was 10 s^"1.

[0258]

The viscosity of the horse defibrinated blood containing 2 mass% PANACET 810s was 5.9 mPa-s, while the viscosity of the horse defibrinated blood containing no blood modifying agent was 50.4 mPa*s. Thus, the horse defibrinated blood containing 2 mass% PANACET 810s clearly had an approximately 90% lower viscosity than the blood containing no blood modifying agent.

It is known that blood contains components such as blood cells and has thixotropy, and it has been found believed that the blood modifying agent of this

disclosure can lower blood viscosity in the low viscosity range. Lowering the blood viscosity presumably allows absorbed menstrual blood to rapidly migrate from the top sheet to the absorbent body.

[0259]

[Example 5]

[Photomicrograph of blood modifying agent-containing blood]

Menstrual blood was sampled from healthy volunteers onto Saran wrap, and PANACET 810s dispersed in a 10-fold mass of phosphate-buffered saline was added to a portion thereof to a PANACET 810s concentration of 1 mass%. The menstrual blood was dropped onto a slide glass, a cover glass was placed thereover, and the state of the

erythrocytes was observed with an optical microscope. A photomicrograph of menstrual blood containing no blood modifying agent is shown in Fig. 23(a), and a

photomicrograph of menstrual blood containing PANACET

810s is shown in Fig. 23(b).

[0260]

As shown Fig. 23, it is seen that the erythrocytes formed aggregates such as rouleaux in the menstrual blood containing no blood modifying agent, while the

erythrocytes were stably dispersed in the menstrual blood containing PANACET 810s. This suggests that the blood modifying agent functions to stabilize erythrocytes in blood.

[0261]

[Example 6]

[Surface tension of blood containing blood modifying agent]

The surface tension of blood containing a blood modifying agent was measured by the pendant drop method, using a Drop Master500 contact angle meter by Kyowa

Interface Science Co., Ltd. The surface tension was measured after adding a prescribed amount of blood modifying agent to sheep defibrinated blood, and

thoroughly shaking.

The measurement was accomplished automatically with a device, and the surface tension γ was determined by the following formula (see Fig. 24) .

[0262 ]

γ = g x p x (de)² x 1/H

g: Gravitational constant

1/H: Correction factor determined from ds/de

p : Density

de: Maximum diameter

ds : Diameter at location of increase by de from dropping edge

[0263]

The density p was measured at the temperatures listed in Table 5, according to JIS K 2249-1995, "Density test methods and density/mass/volume conversion tables", "5. Vibrating density test method".

The measurement was accomplished using a DA-505 by Kyoto Electronics Co., Ltd.

The results are shown in Table 5 below.

[0264]

Table 5

[0265]

Table 5 shows that the blood modifying agent can lower the surface tension of blood despite its very low solubility in water, as seen by a water solubility of about 0.00-about 0.05 g in 100 g of water at 25°C.

Lowering the surface tension of blood presumably allows absorbed blood to rapidly migrate from the top sheet to the absorbent body, without being retained between the top sheet fibers. [0266]

Any of the aforementioned embodiments may also be applied in combination with the modifications. The modifications may also be applied in combination with each other.

[0267]

The explanation above is merely an example, and the invention is in no way restricted by the described embodiments .

[0268]

The presents disclosure relates to the following and any combination thereof.

[Jl]

An absorbent article comprising a liquid-permeable top sheet provided on the skin facing side, a liquid- impermeable back sheet provided on the non-skin facing side and a liquid-retaining absorbent body provided between the top sheet and back sheet, wherein:

at least a portion of at least the skin facing side surface of the top sheet is formed of a resin film having a lubricant layer formed on the skin facing side surface, and

the lubricant layer is water-repellent and/or oil-repellent .

[J2]

An absorbent article according to Jl, wherein the resin film has numerous openings formed for permeation of body fluid.

[J3]

An absorbent article according to Jl or J2, wherein the resin film used as the top sheet is composed of a copolymer of an olefin and another monomer such as an acrylic acid ester or vinyl acetate, or a polyolefin, polyester, polypropylene, polyethylene, polyethylene terephthalate, polyamide, cellulose acetate or the like, and is most preferably a copolymer of an olefin and another monomer, or a polyolefin. [J4]

An absorbent article according to any of J1-J3, wherein the basis weight of the top sheet is at least 1 g/m² and no greater than 40 g/m², preferably at least 10 g/m² and no greater than 35 g/m², and/or the thickness of the top sheet 2A is at least 0.01 mm and no greater than 0.4 mm, preferably at least 0.1 mm and no greater than 0.35 mm.

[J5]

An absorbent article according to any of J1-J4, wherein the top sheet has a concealing property produced for example by mixing a filler such as titanium oxide in a resin.

[J6]

An absorbent article according to J5, wherein the filler is titanium oxide and the titanium oxide content is at least 1% and no greater than 50%, preferably at least 3% and no greater than 15%, with respect to the weight of the resin film.

[J7]

An absorbent article according to any of J1-J6, wherein the basis weight of the resin film layer is at least 1 g/m² and no greater than 30 g/m², preferably at least 3 g/m² and no greater than 15 g/m² and/or the thickness of the resin film layer 31B is at least 0.01 mm and no greater than 0.3 mm, preferably at least 0.03 mm and no greater than 0.15 mm.

[J8]

An absorbent article according to any of J1-J7, wherein the lubricant is a fluorinated compound, a silicon compound or a blood modifying agent.

[J9]

An absorbent article according to any of J1-J8, wherein the coating amount of the lubricant is at least

0.1 g/m² and no greater than 30.0 g/m², preferably at least 1.0 g/m² and no greater than 10.0 g/m². [J10]

An absorbent article according to any of J1-J9, wherein the lubricant is coated over the entire surface of the resin film, or only at the regions corresponding to the areas of the absorbent article where body fluid of the wearer will be excreted.

[Jll]

An absorbent article according to any of J1-J10, wherein the lubricant of the lubricant layer is a blood modifying agent having an IOB of 0.00-0.60, a melting point of no higher than 45°C and a water solubility of no greater than 0.05 g in 100 g of water at 25°C.

[J12]

An absorbent article according to Jll, wherein the vapor pressure of the blood modifying agent is about

0.00-0.01 Pa, preferably about 0.000-0.001 Pa and more preferably about 0.0000-0.0001 Pa, at 1 atmosphere, 25°C, or at 1 atmosphere, 40°C.

[J13]

The absorbent article according to J12, wherein the blood modifying agent is selected from the group

consisting of following items (i)-(iii), and any

combination thereof:

(i) a hydrocarbon;

(ii) a compound having (ii-1) a hydrocarbon moiety, and (ii-2) one or more groups each selected from the group consisting of carbonyl group (-CO-) and oxy group (-0-) inserted between a C-C single bond of the

hydrocarbon moiety; and

(iii) a compound having (iii-1) a hydrocarbon moiety, (iii-2) one or more groups each selected from the group consisting of carbonyl group (-CO-) and oxy group (-0-) inserted between a C-C single bond of the

hydrocarbon moiety, and (iii-3) one or more groups each selected from the group consisting of carboxyl group (-

COOH) and hydroxy! group (-OH) substituting a hydrogen of the hydrocarbon moiety;

with the proviso that when 2 or more oxy groups are inserted in the compound of (ii) or (iii) , the oxy groups are not adjacent.

[J14]

The absorbent article according to any of Jll to J13, wherein the blood modifying agent is selected from the group consisting of following items (i')^_(iii' ) r and any combination thereof:

(i') a hydrocarbon;

(ii') a compound having (ii'-l) a hydrocarbon moiety, and (ii'-2) one or more bonds each selected from the group consisting of carbonyl bond (-CO-) , ester bond (-COO-), carbonate bond (-0C00-) , and ether bond (-0-) inserted between a C-C single bond of the hydrocarbon moiety; and

(iii') a compound having (iii'-l) a hydrocarbon moiety, (iii '-2) one or more bonds each selected from the group consisting of carbonyl bond (-CO-) , ester bond (- COO-) , carbonate bond (-OCOO-) , and ether bond (-0-) inserted between a C-C single bond of the hydrocarbon moiety, and (iii '-3) one or more groups each selected from the group consisting of carboxyl group (-COOH) and hydroxyl group (-OH) substituting a hydrogen on the hydrocarbon moiety;

with the proviso that when 2 or more same or different bonds are inserted in the compound of (ii¹) or

(iii¹), the bonds are not adjacent.

[J15]

The absorbent article according to any one of Jll to J14, wherein the blood modifying agent is selected from the group consisting of following items (A) -(F), and any combination thereof:

(A) an ester of (Al) a compound having a chain hydrocarbon moiety and 2-4 hydroxyl groups substituting hydrogens on the chain hydrocarbon moiety, and (A2) a compound having a chain hydrocarbon moiety and 1 carboxyl group substituting a hydrogen on the chain hydrocarbon moiety;

(B) an ether of (Bl) a compound having a chain hydrocarbon moiety and 2-4 hydroxyl groups substituting hydrogens on the chain hydrocarbon moiety and (B2) a compound having a chain hydrocarbon moiety and 1 hydroxyl group substituting a hydrogen on the chain hydrocarbon moiety;

(C) an ester of (CI) a carboxylic acid, hydroxy acid, alkoxy acid or oxoacid comprising a chain

hydrocarbon moiety and 2-4 carboxyl groups substituting hydrogens on the chain hydrocarbon moiety and (C2) a compound having a chain hydrocarbon moiety and 1 hydroxyl group substituting a hydrogen on the chain hydrocarbon moiety;

(D) a compound having a chain hydrocarbon moiety and one bond selected from the group consisting of an ether bond (-0-) , carbonyl bond (-CO-), ester bond (-COO-) and carbonate bond (-OCOO-) inserted between a C-C single bond of the chain hydrocarbon moiety;

(E) a polyoxy C2-C₆ alkylene glycol, or alkyl ester or alkyl ether thereof; and

(F) a chain hydrocarbon.

[J16]

The absorbent article according to any one of Jll to

J15, wherein the blood modifying agent is selected from the group consisting of (ai) esters of chain hydrocarbon tetraols and fatty acids, (a₂) esters of chain hydrocarbon triols and fatty acids, (a3) esters of chain hydrocarbon diols and fatty acids, (bi) ethers of chain hydrocarbon tetraols and aliphatic monohydric alcohols, (b₂) ethers of chain hydrocarbon triols and aliphatic monohydric

alcohols, (b₃) ethers of chain hydrocarbon diols and aliphatic monohydric alcohols, (ci) esters of chain hydrocarbon tetracarboxylic acids, hydroxy acids, alkoxy acids or oxoacids with 4 carboxyl groups, and aliphatic monohydric alcohols, (c₂) esters of chain hydrocarbon tricarboxylic acids, hydroxy acids, alkoxy acids or oxoacids with 3 carboxyl groups, and aliphatic monohydric alcohols, (C3) esters of chain hydrocarbon dicarboxylic acids, hydroxy acids, alkoxy acids or oxoacids with 2 carboxyl groups, and aliphatic monohydric alcohols, (di) ethers of aliphatic monohydric alcohols and aliphatic monohydric alcohols, (d₂) dialkyl ketones, (da) esters of fatty acids and aliphatic monohydric alcohols, (d4)

dialkyl carbonates, (ei) polyoxy C₂-6 alkylene glycols, (e₂) esters of polyoxy C2-6 alkylene glycols and at least one fatty acid, (e₃) ethers of polyoxy C₂-6 alkylene glycols and at least one aliphatic monohydric alcohol, (e₄) esters of polyoxy C2-6 alkylene glycols with chain hydrocarbon tetracarboxylic acids, chain hydrocarbon tricarboxylic acids or chain hydrocarbon dicarboxylic acids, (es) ethers of polyoxy C₂-6 alkylene glycols with chain hydrocarbon tetraols, chain hydrocarbon triols or chain hydrocarbon diols, and (fi) chain alkanes.

[J17]

An absorbent article according to any one of Jll to

J16, wherein the blood modifying agent is selected from the group consisting of (ai) esters of chain hydrocarbon tetraols and fatty acids, (a₂) esters of chain hydrocarbon triols and fatty acids, (a₃) esters of chain hydrocarbon diols and fatty acids, (c₂) esters of chain hydrocarbon tricarboxylic acids, hydroxy acids, alkoxy acids or oxoacids with 3 carboxyl groups, and aliphatic monohydric alcohols, (c₃) esters of chain hydrocarbon dicarboxylic acids, hydroxy acids, alkoxy acids or oxoacids with 2 carboxyl groups, and aliphatic monohydric alcohols, (d₃) esters of fatty acids and aliphatic monohydric alcohols, (ei) polyoxy C₂-6 alkylene glycols, (e₂) esters of polyoxy C₂_6 alkylene glycols and at least one fatty acid, (e₃) ethers of polyoxy C₂-6 alkylene glycols and at least one aliphatic monohydric alcohol, (e₅) ethers of polyoxy C₂-6 alkylene glycols with chain hydrocarbon tetraols, chain hydrocarbon triols or chain hydrocarbon diols, and (fi) chain alkanes.

[J18]

The absorbent article according to any one of Jll to J17, wherein the blood modifying agent is selected from the group consisting of:

U ISTAR H-408BRS

UNISTAR H-2408BRS-22

and/or the group consisting of

Cetiol SB45DEO

Soy 42

Tri-C2L oil fatty acid glyceride

Tri-CL oil fatty acid glyceride

PANACET 810s

PANACET 800

PANACET 800B

NA36

Tri-coconut fatty acid glyceride

Caprylic acid diglyceride

and/or the group consisting of

COMPOL BL

COMPOL BS

UNISTAR H-208BRS

and/or the group consisting of

Tributyl O-acetylcitrate

and/or the group consisting of

Dioctyl adipate

and/or the group consisting of

ELECTOL WE20

ELECTOL WE40

and/or the group consisting of

UNIOL D-1000

UNIOL D-1200

UNIOL D-3000

UNIOL D-4000

UNIOL PB500

UNIOL PB700

UNIOL PB1000R and/or the group consisting of

WILBRITE cp9

and/or the group consisting of

UNILUBE MS-70K

and/or the group consisting of

UNILUBE 5TP-300KB

UNIOL TG-3000

UNIOL TG-4000

and/or the group consisting of

PARLEAM 6

all as described hereinabove.

[J19]

An absorbent article according to any one of Jl to J18, wherein the top sheet includes a fiber aggregate layer formed on the non-skin facing side of the resin film layer 31B, which fiber aggregate layer has its matrix disrupted at wall sections thereof.

[J20]

An absorbent article according to J19, wherein the fiber aggregate layer is a tissue.

[J21]

An absorbent article according to any one of Jl to J20, wherein:

the top sheet is provided with a plurality of protrusions formed by bending in such a manner that the cross-section is essentially undulating, and arranged in parallel, and bottom sections situated between adjacent protrusions ,

each protrusion including wall sections with a plurality of openings extending along the direction of the protrusion.

[J22]

An absorbent article according to J21, wherein the wall sections are slanted with respect to the bottom sections and the angle formed between the bottom sections

22A and wall sections 24A is greater than 90° and no greater than 165°. [J23]

An absorbent article according to J21 or J22, wherein the open area of each opening is preferably at least 0.001 mm² and no greater than 1 mm², preferably at least 0.01 mm² and no greater than 0.1 mm².

[J24]

An absorbent article according to any of J21 to J23, wherein the proportion of the total open area with respect to the area of the top sheet, i.e. the open area ratio of the top sheet, is at least 5% and no greater than 20%.

[J25]

An absorbent article according to any one of Jl to J24, wherein:

at least the region of the top sheet facing the body fluid excretion hole of the wearer is formed of a resin film having a lubricant layer formed on its skin facing side surface, and

the top sheet and the absorbent body are not bonded at least at the region facing the body fluid excretion hole of the wearer.

[0269]

This application claims the benefit of Japanese Application No. 2011-218544 the entire disclosure of which is incorporated by reference herein.

Claims

[CLAIM 1]

An absorbent article comprising a liquid-permeable top sheet provided on a skin facing side, a liquid- impermeable back sheet provided on a non-skin facing side and a liquid-retaining absorbent body provided between the top sheet and back sheet, wherein:

at least a portion of at least a skin facing side surface of the top sheet is formed of a resin film having a lubricant layer formed on the skin facing side surface, and

the lubricant layer is water-repellent and/or oil-repellent.

[CLAIM 2]

The absorbent article according to claim 1, wherein a lubricant of the lubricant layer is a blood modifying agent having an Inorganic-Organic Balance of 0.00-0.60, a melting point of no higher than 45°C and a water

solubility of no greater than 0.05 g in 100 g of water at 25°C.

[CLAIM 3]

The absorbent article according to claim 2, wherein the blood modifying agent is selected from the group consisting of the following items (i)-(iii), and any combination thereof:

(i) a hydrocarbon;

(ii) a compound having (ii-1) a hydrocarbon moiety, and (ii-2) one or more groups each selected from the group consisting of carbonyl group (-CO-) and oxy group (-0-) inserted between a C-C single bond of the

hydrocarbon moiety; and

(iii) a compound having (iii-1) a hydrocarbon moiety, (iii-2) one or more groups each selected from the group consisting of carbonyl group (-CO-) and oxy group (-0-) inserted between a C-C single bond of the

hydrocarbon moiety, and (iii-3) one or more groups each selected from the group consisting of carboxyl group (- COOH) and hydroxyl group (-OH) substituting a hydrogen of the hydrocarbon moiety;

wherein when 2 or more oxy groups are inserted in the compound of (ii) or (iii) , the oxy groups are not adjacent.

[CLAIM 4]

The absorbent article according to claim 2 or 3, wherein the blood modifying agent is selected from the group consisting of the following items (i')-(iii'), and any combination thereof:

(i¹) a hydrocarbon;

(ii¹) a compound having at least (ii'-l) a

hydrocarbon moiety, and (ii'-2) one or more bonds each selected from the group consisting of carbonyl bond

(-0-) , at least one ester bond (-COO-) , at least one carbonate bond (-OCOO-) , and at least one ether bond (-0- ) inserted between a C-C single bond of the hydrocarbon moiety; and

(iii') a compound having at least (iii'-l) a

hydrocarbon moiety, (iii '-2) one or more bonds each selected from the group consisting of carbonyl bond

(-CO-), at least one ester bond (-COO-) , at least one carbonate bond (-OCOO-) , and at least one ether bond (-0- ) inserted between a C-C single bond of the hydrocarbon moiety, and (iii '-3) one or more groups each selected from the group consisting of carboxyl group (-C00H) and hydroxyl group (-0H) substituting a hydrogen on the hydrocarbon moiety;

wherein when 2 or more same or different bonds are inserted in the compound of (ii') or (iii'), the bonds are not adjacent.

[CLAIM 5]

The absorbent article according to any one of claims 2 to 4, wherein the blood modifying agent is selected from the group consisting of the following items (A) -(F), and any combination thereof:

(A) an ester of (Al) a compound having a chain hydrocarbon moiety and 2-4 hydroxyl groups substituting hydrogens on the chain hydrocarbon moiety, and (A2) a compound having a chain hydrocarbon moiety and 1 carboxyl group substituting a hydrogen on the chain hydrocarbon moiety;

(B) an ether of (Bl) a compound having a chain hydrocarbon moiety and 2-4 hydroxyl groups substituting hydrogens on the chain hydrocarbon moiety and (B2) a compound having a chain hydrocarbon moiety and 1 hydroxyl group substituting a hydrogen on the chain hydrocarbon moiety;

(C) an ester of (CI) a carboxylic acid, hydroxy acid, alkoxy acid or oxoacid comprising a chain

hydrocarbon moiety and 2-4 carboxyl groups substituting hydrogens on the chain hydrocarbon moiety and (C2) a compound having a chain hydrocarbon moiety and 1 hydroxyl group substituting a hydrogen on the chain hydrocarbon moiety;

(D) a compound having a chain hydrocarbon moiety and one bond selected from the group consisting of an ether bond (-0-) , carbonyl bond (-CO-), ester bond (-COO-) and carbonate bond (-OCOO-) inserted between a C-C single bond of the chain hydrocarbon moiety;

(E) a polyoxy C2-Cg alkylene glycol, or alkyl ester or alkyl ether thereof; and

(F) a chain hydrocarbon.

[CLAIM 6]

The absorbent article according to any one of claims 2 to 5, wherein the blood modifying agent is selected from the group consisting of (ai) esters of chain

hydrocarbon tetraols and at least one fatty acid, (a₂) esters of chain hydrocarbon triols and at least one fatty acid, (a₃) esters of chain hydrocarbon diols and at least one fatty acid, (bi) ethers of chain hydrocarbon tetraols and at least one aliphatic monohydric alcohol, (b₂) ethers of chain hydrocarbon triols and at least one aliphatic monohydric alcohol, (b₃) ethers of chain hydrocarbon diols and at least one aliphatic monohydric alcohol, (ci) esters of chain hydrocarbon tetracarboxylic acids, hydroxy acids, alkoxy acids or oxoacids with 4 carboxyl groups, and at least one aliphatic monohydric alcohol, (C2) esters of chain hydrocarbon tricarboxylic acids, hydroxy acids, alkoxy acids or oxoacids with 3 carboxyl groups, and at least one aliphatic monohydric alcohol, (c₃) esters of chain hydrocarbon dicarboxylic acids, hydroxy acids, alkoxy acids or oxoacids with 2 carboxyl groups, and at least one aliphatic monohydric alcohol, (di) ethers of aliphatic monohydric alcohols and aliphatic monohydric alcohols, (da) dialkyl ketones, (d₃) esters of fatty acids and aliphatic monohydric alcohols, (d₄) dialkyl

carbonates, (ei) polyoxy C2-_.6 alkylene glycols, (e₂) esters of polyoxy C₂-6 alkylene glycols and at least one fatty acid, (e₃) ethers of polyoxy C₂_₆ alkylene glycols and at least one aliphatic monohydric alcohol, (e₄) esters of polyoxy C2-6 alkylene glycols with chain hydrocarbon tetracarboxylic acids, chain hydrocarbon tricarboxylic acids or chain hydrocarbon dicarboxylic acids, (es) ethers of polyoxy C₂-6 alkylene glycols with chain hydrocarbon tetraols, chain hydrocarbon triols or chain hydrocarbon diols, and (fi) chain alkanes.

[CLAIM 7]

The absorbent article according to any one of claims

1 to 6, wherein:

the top sheet is provided with a plurality of protrusions arranged in parallel, and bottom sections situated between adjacent protrusions,

each protrusion including wall sections with a plurality of openings arranged along the direction of the protrusion.

[CLAIM 8]

The absorbent article according to any one of claims 1 to 7, wherein:

the resin film having the lubricant layer formed on the skin facing side surface is formed in at least a region of top sheet for facing the body fluid excretion hole of wearer, and

the top sheet and the absorbent body are not bonded at least at the region for facing the body fluid excretion hole of the wearer.