GB2588699A

GB2588699A - Nonwoven fabric for absorbent article

Info

Publication number: GB2588699A
Application number: GB2003548.1A
Authority: GB
Inventors: Kinugasa Yoshihiko; Taniguchi Masahiro; Seto Yoshihiko
Original assignee: Kao Corp
Current assignee: Kao Corp
Priority date: 2019-01-16
Filing date: 2019-01-16
Publication date: 2021-05-05
Anticipated expiration: 2039-01-16
Also published as: GB2588699B; FR3091647B1; TWI707668B; JP6595149B1; KR20200090730A; TW202031219A; DE112019000105T5; RU2728154C1; JPWO2020148818A1; CN111757720B; CN111757720A; WO2020148818A1; FR3091647A1; GB202003548D0; MY196357A; KR102192284B1

Abstract

This nonwoven fabric for an absorbent article comprises thermoplastic fibers, the nonwoven fabric including a plurality of layered portions 1 in which a piece of nonwoven fabric has parts that are folded over to form three or more overlapping layers in the thickness direction, wherein in each layered portion 1, a first face layer 2 that is located on a first face side Z1 of the nonwoven fabric and a second face layer 3 that is located on a second face side Z2 are flat and the fibers of the first face layer 2 and the second face layer 3 are oriented in a planar direction.

Description

DESCRIPTION

TITLE OF THE INVENTION: NONWOVEN FABRIC FOR ABSORBENT ARTICLE

FIELD OF THE INVENTION

The present invention relates to a nonwoven fabric for an absorbent article.

BACKGROUND OF THE INVENTION

A nonwoven fabric is often used in an absorbent article such as a sanitary towel or a nappy. Technologies for providing such a nonwoven fabric with various functions are known. These include ones that, with a view to reducing chafing of the skin, enable surface movement of the nonwoven fabric by means of a concavo-convex shape (for example, the nonwoven fabrics described in Patent Literatures 1 to 3). The convex portion of nonwoven fabric of concavoconvex shape is adapted to movably contact the skin.

The nonwoven fabric described in Patent Literature 1 has a plurality of projecting portions on both surfaces thereof. Multiple projecting portions on one and another side surfaces, termed first projecting portions and second projecting portions, are adapted to project from these opposite side surfaces and be continuous with one another via annular wall portions. Fibres constituting the nonwoven fabric have radial fibre orientation whereby the fibres converge in thickness direction from the annular wall portions toward top portions of the second projecting portions.

Patent Literature 2 describes a topsheet having a plurality of loop portions being convex toward the skin of the wearer. This topsheet has a two-layer structure in which a fibre layer constituting the loop portions is intermittently bonded to a base material layer. The loop portions of the structure rise from between the intermittently bonded portions to stick out significantly toward the skin of the wearer.

Patent Literature 3 describes a nonwoven fabric intended for use as an absorbent article that adequately retains three-dimensional shape even under compression. Specifically, the nonwoven fabric has projecting portions extending outward from a first surface. The projecting portions have mushroom-like caps and no hinge-like structure allowing folding.

CITATION LIST

PATENT LITERATURES {0003} Patent Literature 1: JP-A-2013-119012 ("JP-A" means unexamined published Japanese patent application) Patent Literature 2: JP-A-2004-121701 Patent Literature 3: JP-T-2017-528614 ("JP-T" means a published Japanese translation of PCT international application)

SUMMARY OF THE INVENTION

The present invention provides a nonwoven fabric comprising thermoplastic fibres.

In an embodiment, the nonwoven fabric comprises a plurality of laminated parts in which one sheet of the nonwoven fabric is partially folded to form three or more layers overlapped in a thickness direction.

In an embodiment, in the laminated parts, a first surface layer positioned on a first surface side of the nonwoven fabric and a second surface layer positioned on a second surface side thereof are flat.

In an embodiment, fibres in the first surface layer and the second surface layer are oriented in a plane direction.

In an embodiment, the nonwoven fabric is a 'nonwoven fabric for an absorbent article.' In an embodiment, the nonwoven fabric comprises a thermally fused part between fibres in each layer of the nonwoven fabric, and the laminated part comprises a folding structure through no bonding means.

In an embodiment, the nonwoven fabric comprises a single-layer part between the laminated parts adjacent to each other in a plane view of the nonwoven fabric.

In an embodiment, the first surface layer comprises a fibre of 2.4 dtex or less.

In an embodiment, basis weight in the first surface layer is larger than basis weight in the second surface layer.

In an embodiment, the nonwoven fabric comprises a plurality of regions in which the laminated part extends in a certain direction in the plane view of the nonwoven fabric.

In an embodiment, the nonwoven fabric comprises a region of a single-layer part surrounded by the laminated part in the plane view of the nonwoven fabric.

In an embodiment, the region of the single-layer part comprises a curved portion in an outer edge in the plane view.

In an embodiment, a boundary between the single-layer part and the laminated part in the curved portion is arranged on the second surface side of the nonwoven fabric.

In an embodiment, fibres in the region in which the laminated part extends in one direction exhibits the same orientation direction on at least one side of the first surface side and the second surface side of the nonwoven fabric.

In an embodiment, fibres in the first surface layer of the laminated part and fibres in the single-layer part exhibit the same orientation direction.

In an embodiment, the nonwoven fabric comprises a single-layer part between the laminated parts adjacent to each other in the plane view of the nonwoven fabric, and a region in which the single-layer part extends in a certain direction is present.

In an embodiment, a region in which the single-layer part extends in one direction perpendicular to the certain direction is present.

In an embodiment, the nonwoven fabric comprises a single-layer part, and a region of the laminated part surrounded by the single-layer parts is present in the plane view of the nonwoven fabric.

In an embodiment, another single-layer part is further present in the region of the laminated part surrounded by the single-layer parts.

In an embodiment, fibres in the single-layer part extending in the certain direction and fibres in the single-layer part extending in one direction perpendicular to the certain direction exhibit the same orientation direction. {0008} In an embodiment, the expression "the first surface layer or the second surface layer is flat" means that, upon placing the nonwoven fabric on a table with the first surface layer or the second surface layer on a lower side, and putting a transparent plate to be a load of 35 Pa on an upper side, a ratio of an area in contact with the transparent plate is at a predetermined level or more when viewed from above. The ratio of the area in which the first surface layer or the second surface layer is in contact with the transparent plate is arbitrarily 50% or more and 99% or less, preferably 60% or more, and more preferably 70% or more, and/or preferably 95% or less, and more preferably 90% or less.

In an embodiment, the expression "fibres in the first surface layer or the second surface layer are oriented in a plane direction" means an inequality: the number of fibres P1 > the number of fibres P2 holds in comparing the number of fibres P1 with the number of fibres P2, wherein the number of fibres P1 is the number of fibres crossing with each side of a virtual square when the virtual square is arranged in observing the nonwoven fabric for an absorbent article from the first surface side or the second surface side, and the number of fibres P2 is the number of fibres crossing with each side of a virtual square when the virtual square is arranged in observing a cross section of the first surface layer or the second surface layer along a thickness direction.

In an embodiment, the expression "fibres in the first surface layer or the second surface layer are oriented in a plane direction" means that a ratio P1/P2 is 1.2 or more and 10 or less, preferably 1.5 or more, and more preferably 2 or more, and/or preferably 9 or less, and more preferably 8 or less with regard to the ratio of the number of fibres P1 to the number of the fibres P2, wherein the number of fibres P1 is the number of fibres crossing with each side of a virtual square when the virtual square is arranged in observing the nonwoven fabric for an absorbent article from the first surface side or the second surface side, and the number of fibres P2 is the number of fibres crossing with each side of a virtual square when the virtual square is arranged in observing a cross section of the first surface layer or the second surface layer along a thickness direction.

In an embodiment, the first surface layer comprises a fibre of 0.2 dtex or more and 2.4 dtex or less, preferably 0.5 dtex or more, and more preferably 0.8 dtex or more, and/or preferably 2 dtex or less, and more preferably 1.8 dtex or less.

In an embodiment, a ratio of basis weight G1 in the first surface layer to basis weight G2 in the second surface layer (basis weight G1 in the first surface layer / basis weight G2 in the second surface layer) is 1.2 or more and 10 or less, preferably 1.5 or more, and more preferably 2 or more, and/or preferably 8 or less, and more preferably 6 or less.

In an embodiment, the expression "fibres exhibit the same orientation direction" means that a ratio (the number of fibres P3 / the number of fibres P4) is 1.2 or more in each site to be compared, and arbitrarily, preferably 1.5 or more, and more preferably 2 or more with regard to the ratio of the number of fibres P3 to the number of fibres P4, wherein the number of fibres P3 is the muber of fibres crossing with two sides in one direction of a virtual square when the virtual square is arranged in observing a surface of an object part of the nonwoven fabric for an absorbent article along a plane direction, and the number of fibres P4 is the number of fibres crossing with two sides in the other direction of the virtual square.

In an embodiment, an apparent thickness H1 under a load of 35 Pa is 0.5 mm or more and 5 mm or less, preferably 1 mm or more, more preferably 1.2 mm or more, and/or preferably 4 mm or less, more preferably 3 mm or less.

In an embodiment, an apparent thickness H2 under a load of 1 kPa is 0.2 mm or more and 3 mm or less, preferably 0.3 mm or more, more preferably 0.5 mm or more, and/or preferably 2 mm or less, more preferably 1.5 mm or less.

In an embodiment, a ratio of an apparent thickness H2 under a load of 1 kPa to an apparent thickness H1 under a load of 35 Pa is 10% or more and 80% or less, preferably 20% or more, and more preferably 30% or more.

In an embodiment, a ratio of an area E2 of the laminated part to a total area El of the nonwoven fabric for an absorbent article in a plane view is 10% or more and 95% or less, preferably 15% or more, and more preferably 20% or more.

In an embodiment, part of the laminated part is formed into a five-layer part In an embodiment, in the laminated part, a constricted portion is arranged in one or more selected from a connecting part between an end portion of the first surface layer, and, one end portion of an intermediate layer between the first surface layer and the second surface layer, a connecting part between an end portion of the second surface layer and the end portion of the first surface layer, and a connecting part between the other end portion of the intermediate layer and the end portion of the second surface layer.

In an embodiment, in the laminated part, a space portion is arranged between the second surface layer, and, the intermediate layer between the first surface layer and the second surface layer.

Further, the present invention provides an absorbent article using the nonwoven fabric and/or the 'nonwoven fabric for an absorbent article.' In an embodiment, the absorbent article comprises the nonwoven fabric and/or the 'nonwoven fabric for an absorbent article' as a topsheet by directing the first surface layer toward a skin-facing surface side, and an absorbent body 20 on the second surface side of the topsheet.

In an embodiment, a constituent member of the absorbent article is pasted on the second surface side of the nonwoven fabric and/or the 'nonwoven fabric for an absorbent article,' and arbitrarily, an adhesive is arranged in an area of less than 70% on a whole surface on the second surface side of the nonwoven fabric for an absorbent article, and arbitrarily, a ratio of the area of the adhesive to the whole surface on the second surface side of the nonwoven fabric for an absorbent article is preferably 65% or less, and more preferably 50% or less, and/or preferably 10% or more, more preferably 15% or more, and further preferably 20% or more.

In an embodiment, a nonwoven fabric contained in the absorbent article is in the above-described state in the absorbent article being in a folded state.

In an embodiment, a nonwoven fabric contained in the absorbent article is in the above-described state in an absorbent article package in which a plurality of absorbent articles is housed.

Other and further objects, features and advantages of the invention will appear more fully from the following description, appropriately referring to the 10 accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS {0011}

{FIG. 1} FIG. 1 is a cross-sectional drawing showing one preferable embodiment (first embodiment) of the nonwoven fabric for an absorbent article according to the present invention.

{FIG. 2} FIG. 2(A) is an enlarged cross-sectional drawing of a laminated part shown in FIG. 1, and FIG. 2(B) is an enlarged cross-sectional drawing showing a modified example of the laminated part shown in FIG. 2(A).

{FIG. 3} FIG. 3 is a plane drawing obtained by viewing, from a second surface side, the nonwoven fabric for an absorbent article in the first embodiment.

{FIG. 4} FIG. 4 is a cross-sectional drawing schematically showing another preferable embodiment (second embodiment) of a nonwoven fabric for an absorbent article according to the present invention.

{FIG 5} FIG. 5 is a plane drawing obtained by viewing, from a second surface side, the nonwoven fabric for an absorbent article in the second embodiment. {FIG. 6} FIG. 6 is an explanatory drawing schematically showing one preferable example of a method for producing a nonwoven fabric for an absorbent article in the first embodiment and the second embodiment. FIG. 6(A) is an explanatory drawing showing a step of arranging a fibre web on a support male material and pushing a support female material into the support male material from above the fibre web. FIG. 6(B) is an explanatory drawing showing a step of blowing first hot air from above the support female material and shaping the fibre web. FIG. 6(C) is an explanatory drawing showing a step of removing the support female material, and blowing second hot air from above a shaped fibre web to fuse fibres to each other.

DESCRIPTION OF EMBODIMENTS

The present invention relates to a nonwoven fabric for an absorbent article in which the smooth texture on the surface of the nonwoven fabric and prevention of chafing of the skin in contact with the surface of the nonwoven fabric are simultaneously improved.

In the nonwoven fabrics having the concave-convex shapes described in Patent Literatures 1 to 3, convex portions (projecting portions) can move relative to skin in contact with a surface of the nonwoven fabric so as to follow the skin, whereby chafing of the skin can be mitigated. However, contact area decreases because the skin is in contact with the vicinity of top portions of the convex portions (projecting portions). Room for improvement therefore remains as regards smooth feel of the nonwoven fabric surface.

On the other hand, a flat-surfaced nonwoven fabric can be expected to give smooth feel. However, in this case, no movability like that of a concave-convex shape can be achieved. Therefore, flat-surfaced nonwoven fabric also has room for improvement from a viewpoint of reducing chafing of the skin in contact with the surface of the nonwoven fabric.

The nonwoven fabric for an absorbent article according to the present invention can be a material in which the smooth texture on the surface of the nonwoven fabric and prevention of chafing of the skin in contact with the surface of the nonwoven fabric are simultaneously improved.

In the present invention, the term 'absorbent article" means an article that absorbs and holds various body fluids such as urine and menstrual blood.

Specific examples thereof include various materials such as a nappy, a sanitary towel, a urine pad and an incontinence pad. The absorbent article has a topsheet on a skin-facing surface side, a backsheet on a non-skin-facing surface side, and a liquid-retainable absorbent body arranged between the topsheet and the backsheet. Further, in addition thereto, the absorbent article may have other members, when necessary. In a member configuration of this absorbent article, the nonwoven fabric for an absorbent article according to the present invention is preferably used as a member arranged in a position in contact with the skin. For example, the nonwoven fabric for an absorbent article is preferably used as the topsheet. Furthermore, the nonwoven fabric for an absorbent article is preferably used as a sheet covering a place further on the non-skin-facing surface side of the backsheet.

In the present invention, unless otherwise specified, a side that is brought into contact with the human body is referred to as skin-facing surface side, and the side that is opposite to the above-mentioned side is referred to as non-skinfacing surface side. These terms are used as terms representing the relative positional relationship in the member configuration of the absorbent article, even in connection with members that do not have a surface that is brought into contact with the human body. The direction positioned on the frontal side of the human body at the time of wearing is referred to as front, and the direction positioned on the rear side is referred to as rear. The direction normal to the top surface or the back surface of the absorbent article is referred to thickness direction.

A preferred one embodiment of the nonwoven fabric for an absorbent article according to the present invention will be explained below, referring to the drawings.

{0018} FIG. 1 shows a cross section of a nonwoven fabric 10 for an absorbent article (hereinafter, also referred to merely as a nonwoven fabric 10) in the first embodiment. The nonwoven fabric 10 has a first surface side Z1, and a second surface side Z2 which is on a side opposite to the first surface side. Either the first surface side Z1 or the second surface side Z2 may be directed toward a side of the absorbent body of the absorbent article. In the embodiment, the first surface side Z1 is shown as a surface side directed outward, and the second surface side Z2 is shown as a surface side directed to the absorbent body, based on the liquid-retainable absorbent body in the absorbent article, and the nonwoven fabric is preferably used in such a manner. For example, when the nonwoven fabric 10 is applied as the topsheet, the first surface side Z1 serves as the surface side in contact with the skin, and the second surface side Z2 serves as the surface side directed to the absorbent body. When the nonwoven fabric is applied as the sheet covering the non-skin-facing surface side of the backsheet, the first surface side Z1 serves as an outermost surface side of the absorbent article (outermost non-skin-facing surface side), and the second surface side Z2 serves as the surface side directed to the absorbent body.

{0019} The nonwoven fabric 10 is one sheet of nonwoven fabric having thermoplastic fibres. The term "one sheet of nonwoven fabric" as used herein refers to a material after a fibre web containing thermoplastic fibres is thermally fused at fibre intersection points (the material being processed into the nonwoven fabric by air-through processing or the like), and a material in which the fibre webs are laminated before thermal fusion and processed into the nonwoven fabric is defined as one sheet of nonwoven fabric. Whether or not the fibre webs are laminated before thermal fusion can be distinguished by observing the nonwoven fabric by a microscope. In the nonwoven fabric produced, if a region in which a plurality of fibres is fused (fused over a region of fibre intersection points) to be formed into a film is not found, such a material can be defined as "one sheet of nonwoven fabric". For example, a material having a fused region (fused region extending to a plurality of fibre intersection points) by embossing is not one sheet of nonwoven fabric as "a material in which nonwoven fabrics are laminated". Neither a material in which nonwoven fabrics produced by thermal fusion are bonded to each other by embossing nor a material in which another fibre web is laminated on the nonwoven fabric produced by thermal fusion to bond the resulting material by embossing is one sheet of nonwoven fabric. In addition, it is not precluded to be subjected to embossing for other purposes such as bonding with other sheets in a step after the fibre web is processed into the nonwoven fabric, for example, in a step of incorporating the nonwoven fabric into the absorbent article.

The nonwoven fabric 10 has a plurality of laminated parts 1 in which one sheet of nonwoven fabric is partially folded into three or more layers overlapped in the thickness direction. In the embodiment, as shown in the cross section in FIG. 1, in the laminated part 1, a first surface layer 2 on the first surface side 71, a second surface layer 3 on the second surface side 72, and an intermediate layer 4 between both the layers are overlapped in the thickness direction into three layers. The first surface layer 2 and the second surface layer 3 of the laminated part 1 are flat. In the present invention, the laminated part is not limited to three layers in the embodiment, and may have four or more layers.

{0021} Here, the expression "overlapped in the thickness direction" means that, when a virtual line L1 perpendicular to the thickness direction is drawn relative to the cross section of the laminated part 1, all of the first surface layer 2, the intermediate layer 4 and the second surface layer 3 are arranged in a state of being pierced by the vertical line U. This case is not limited to a case where the first surface layer 2, the intermediate layer 4 and the second surface layer 3 are all perfectly overlapped, and includes a case where these layers are partially overlapped.

The expression "the first surface layer 2 and the second surface layer 3 are flat" means that, upon placing the nonwoven fabric 10 on a horizontal table T with the first surface layer 2 or the second surface layer 3 downward, and putting a transparent plate to be a load of 35 Pa thereon, a ratio of an area in contact with the transparent plate is at a predetermined level or more when viewed from above. Upon measurement, a nonwoven fabric having a size equal to or larger than 5 cm x 5 cm is arranged. From a viewpoint of the smooth texture, the ratio of the area in which the first surface layer 2 or the second surface layer 3 is in contact with the transparent plate is preferably 50% or more, more preferably 60% or more, and further preferably 70% or more.

From a viewpoint of not inhibiting movement, the ratio is preferably 99% or less, more preferably 95% or less, and further preferably 90% or less.

From a viewpoint of smoothness, the ratio of the area in which the first surface layer 2 or the second surface layer 3 is in contact with the transparent plate is preferably 50% or more and 99% or less, more preferably 60% or more and 95% or less, and further preferably 70% or more and 90% or less.

In the nonwoven fabric 10, fibres in each of the first surface layer 2 and the second surface layer 3 are oriented in a plane direction. The fibres are oriented in the plane direction in the first surface layer 2 and second surface layer 3, which are flat, whereby the smooth texture along an orientation direction is obtained. Simultaneously, the nonwoven fabric 10 has, while having the flat surfaces, a movable region 5 in which the first surface layer 2 and the second surface layer 3 can move in directions opposite to each other with the intermediate layer 4 as an axis in the laminated part 1. According to movable action of this movable region 5, in the nonwoven fabric 10, followability relative to movement of the skin is improved into improved prevention of chafing of the skin in contact with the surface of the nonwoven fabric. Thus, the nonwoven fabric 10 is formed into a material in which the smooth texture on the surface of the nonwoven fabric and the prevention of chafing of the skin in contact with the surface of the nonwoven fabric are simultaneously improved.

Here, the expression "fibres in each of the first surface layer 2 and the second surface layer 3 are oriented in the plane direction" means an inequality: the number of fibres P1 > the number of fibres P2 holds in comparing the number of fibres P1 with the number of fibres P2. The number of fibres P1 is the number of fibres crossing with each side of a virtual square when the virtual square is arranged in observing the nonwoven fabric 10 from the first surface side 71 or the second surface side Z2. The number of fibres P2 is the number of fibres crossing with each side of a virtual square when the virtual square is arranged in observing a cross section of the first surface layer 2 or the second surface layer 3 along the thickness direction.

The numbers of fibres P1 and P2 are measured by the method described below. When the nonwoven fabric is incorporated thereinto as a constituent member of the absorbent article, an adhesive used in the absorbent article is solidified by a cooling means such as a cold spray, and a measurement object nonwoven fabric is carefully peeled off and used for measurement. On the occasion, the adhesive is removed using an organic solvent. Such a treatment is performed in the same manner as in other measuring methods in this specification.

{0026} (Method for measuring the numbers of fibres P1 and P2) (i) A measurement object nonwoven fabric is cut into a square of 2 cm x 2 cm, a cut piece is applied as a sample, and the sample is observed from the first surface side 71 or the second surface side 72. A scanning electron microscope (SEM) is preferably used to the observation, for example. As the SEM, JCM- 6100Plus (manufactured by JEOL Ltd.) is used, for example. In SEM observation, vapour deposition treatment is preferably applied to the sample in advance by a recommended method.

(ii) A centre of the surface of the first surface layer 2 or the second surface layer 3 is magnified at a magnification of 50 times relative to a SEM image, and is shown in a centre of an observation screen. A virtual square having one side of 500 pm with the centre of the screen as an intersection point of diagonal lines is drawn to count the number of fibres P1 crossing with each side of the square.

In the same manner, a virtual square having one side of 500 pm is drawn relative to a cross section of the first surface layer 2 or the second surface layer 3 along the thickness direction to count the number of fibres P2 crossing with each side of the square (iv) These are measured in arbitrary three places in the measurement object nonwoven fabric, and the values are averaged. The averaged values are taken as the numbers of fibres P1 and P2 of the measurement object nonwoven fabric, respectively. At this time, in the arbitrary three places, an angle of each side of the square is not changed relative to the nonwoven fabric. That is, the side of the square in which P1 in the first place is measured should be in parallel with the side of the square in which P1 in the second place is measured. The number of fibres bigger than the other is specified as P1 and the other is specified as P2 in the first place amongst the three places.

From a viewpoint of further improving the smooth texture on the surface of the nonwoven fabric 10, a ratio P1/P2 with regard to the number of fibres P1 to the number of fibres P2, to be obtained by the above-described measurement, is preferably 1.2 or more, more preferably 1.5 or more, and further preferably 2 or more.

From a viewpoint of a strength balance of the nonwoven fabric, the ratio P1/P2 is preferably 10 or less, more preferably 9 or less, and further preferably 8 or less.

The ratio P1/P2 is preferably 1.2 or more and 10 or less, more preferably 1.5 or more and 9 or less, and further preferably 2 or more and 8 or less.

{0028} The nonwoven fabric 10 preferably has a thermally fused portion between the respective fibres in each layer (each layer of the laminated part 1), and a folding structure through no bonding means. Such a structure is preferably arranged in the first surface layer 2 and the second surface layer 3 of the laminated part 1, and is more preferably arranged in the intermediate layer 4 in addition thereto. In each layer, a shape is held by thermal fusion, and each layer is folded through no bonding means, whereby the first surface layer 2 and the second surface layer 3 can be smoothly moved in the directions opposite to each other with the intermediate layer 4 as the axis.

In the nonwoven fabric 10, the laminated part 1 serving as the movable region 5 has the structure as described below. That is, as shown in FIG. 2(A), one end portion 4A of the intermediate layer 4 is connected to an end portion 2A of the first surface layer 2. The other end portion 43 of the intermediate layer 4 is connected to an end portion 3A of the second surface layer 3. One end portion 4A and the other end portion 4B of the intermediate layer 4 are not overlapped in the thickness direction. Thus, the first surface layer 2, the intermediate layer 4 and the second surface layer 3 are configured to be overlapped in the thickness direction. Connecting parts between the first surface layer 2 and the intermediate layer 4, and between the intermediate layer 4 and the second surface layer 3 serve as a folding starting point (fold line portion). Then, the laminated part 1 is folded into a Z-shape in a cross sectional view through no connecting means.

Thus, the first surface layer 2 and the second surface layer 3 connected to both the end portions 4A, 43 of the intermediate layer 4, move so as to be extruded in the directions opposite to each other with the intermediate layer 4 as the axis, whereby the laminated part 1 can move. At this time, the laminated part 1 can move along the plane direction in which the connecting part between the first surface layer 2 and the intermediate layer 4 and the connecting part between the intermediate layer 4 and the second surface layer 3 are aligned and arranged before being movable.

For example, when the nonwoven fabric 10 is applied as the topsheet of the absorbent article, the second surface layer 3 of the nonwoven fabric 10 is fixed to the absorbent body, and the first surface layer 2 is brought into contact with the skin. Shear force in the plane direction is applied to the first surface layer 2 by the skin in contact therewith. On the occasion, the laminated part 1 acts as described below. That is, the first surface layer 2 pulls one end portion 4A of the intermediate layer 4 so as to try to move in following the skin. Then, one end portion 4A moves in the plane direction so as to come close to a position of the other end portion 4B. Thus, the first surface layer 2 moves in the plane direction in following the skin relative to the fixed second surface layer 3.

Therefore, the nonwoven fabric 10 can develop the movable action as in the concavo-convex shape even with the flat first surface layer 2.

In the cross section of this laminated part 1, from a viewpoint of forming the laminated part 1 into a structure in which the laminated part 1 is overlapped in the thickness direction, an angle 81 formed between the intermediate layer 4 and the first surface layer 2 and an angle 82 formed between the intermediate layer 4 and the second surface layer 2 are preferably acute.

The angle 81 and the angle 82 are preferably 30° or less, more preferably 20° or less, and further preferably 10° or less, and as the angle is smaller, such a case is better.

However, the angle is practically 10 or more.

The angle 01 and the angle 82 are adjusted within the above-described range, whereby the smooth texture on the surface of the nonwoven fabric can be realised and movability in the plane direction as mentioned above can be more favourably developed.

In the nonwoven fabric 10, from a viewpoint of further improving the above-described movability, as shown in FIG. 2(B), a constricted portion 6 which can serve as a hinge of the movable region 5 is preferably present in one or more selected from the connecting part between the end portion 2A of the first surface layer 2 and one end portion 4A of the intermediate layer 4, the connecting part between the end portion 3A of the second surface layer 3 and the end portion 2A of the first surface layer 2, and the connecting part between the other end portion 43 of the intermediate layer 4 and the end portion 3A of the second surface layer 3.

From the same viewpoint, a stripe-shaped space portion 13 connected to an opening 12 on the first surface side Z1 is preferably arranged between the intermediate layer 4 and the second surface layer 3.

In the nonwoven fabric 10, a folding direction of the laminated part 1 may be the same as each other, as shown in FIG. 1, or may be different from each other for each laminated part 1.

A size of the laminated part 1 in the plane direction may be the same as or different from each other.

A size of the opening 12 on the first surface side Z1 may be the same as each other or may be different from each other for each laminated part 1.

However, from a viewpoint of improving the smooth texture on the first surface side 71, an area ratio of the opening 12 in a total area on the first surface side Z1 of the nonwoven fabric 10 is preferably as small as possible.

The area ratio of the opening 12 in the total area on the first surface side 71 of the nonwoven fabric 10 is preferably 3% or more and 30% or less, more 25 preferably 5% or more, and more preferably 20% or less.

In a plane view of the nonwoven fabric 10, as shown in FIG. 3, a single-layer part 7 is preferably arranged between the laminated parts 1 adjacent to each other. The single-layer part 7 is interposed, whereby the plurality of laminated parts 1 is separately arranged, respectively. Then, the plurality of laminated parts 1 can independently move in the plane direction to further improve the prevention of chafing of the skin. Moreover, room for developing overlap of the laminated parts 1 increases with the single-layer part 7 as a starting point. That is, a movable range of the movable region 5 can be increased.

The single-layer part 7 may be arranged on any of the first surface side 10 Z1 and the second surface side Z2, but from a viewpoint of improving the smooth texture on the first surface side Z1, the single-layer part 7 is preferably arranged on the first surface side Zl.

In the nonwoven fabric 10, from a viewpoint of realising the smoother texture, the first surface layer 2 preferably has fibres of 2.4 dtex or less, more preferably 2 dtex or less, and further preferably 1.8 dtex or less.

From a viewpoint in producing the fibres or the nonwoven fabric, the first surface layer 2 preferably has fibres of 0.2 dtex or more, more preferably 0.5 dtex or more, and further preferably 0.8 dtex or more.

The first surface layer 2 preferably has fibres of 0.2 dtex or more and 2.4 dtex or less, more preferably 0.5 dtex or more and 2 dtex or less, and further preferably 0.8 dtex or more and 1.8 dtex or less.

In the nonwoven fabric 10, from a viewpoint of realising the smoother texture, the basis weight G1 in the first surface layer 2 is preferably larger than the basis weight G2 in the second surface layer 3.

From the same viewpoint, the ratio of the basis weight G1 in the first surface layer 2 to the basis weight G2 in the second surface layer 3 (basis weight G1 in the first surface layer! basis weight G2 in the second surface layer) is preferably 1.2 or more, more preferably 1.5 or more, and further preferably 2 or more From a viewpoint of holding nonwoven fabric strength on the second surface side 72, the ratio (basis weight G1 in the first surface layer! basis weight G2 in the second surface layer) is preferably 10 or less, more preferably 8 or less, and further preferably 6 or less.

The ratio (basis weight G1 in the first surface layer! basis weight G2 in the second surface layer) is preferably 1.2 or more and 10 or less, more preferably 1.5 or more and 8 or less, and further preferably 2 or more and 6 or less.

In addition thereto, as shown in FIG. 3, the nonwoven fabric 10 preferably has the following configuration in the plane view.

{0039} In the plane view of the nonwoven fabric 10, a plurality of regions 14 in which the laminated part 1 extends in a certain direction is preferably present. In FIG. 3, the regions 14 in which the laminated part 1 extends are directed to a longitudinal direction Y of the nonwoven fabric 10, and the plurality thereof is separately aligned in parallel in a crosswise direction X. This extending direction is not limited to the longitudinal direction Y shown in FIG. 3, and may be the crosswise direction X perpendicular to the longitudinal direction Y, or may be various directions crossing with these directions. In addition, the longitudinal direction Y and the crosswise direction X of the nonwoven fabric 10 are a machine direction (MD) during production and a cross direction (CD) perpendicular thereto, respectively.

Thus, the plurality of regions 14 in which the laminated part 1 extends is present, whereby the laminated parts 1 are uniformly aligned, and the smooth texture can be more easily obtained without shaping a concavo-convex pattern. {0040} In addition, in the laminated part 1 of the nonwoven fabric 10 shown in FIG. 3, the connecting part between the first surface layer 2 and the intermediate layer 4, and the connecting part between the intermediate layer 4 and the second surface layer 3, as shown in FIG. 1, are aligned and arranged in the crosswise direction X. Therefore, the laminated part 1 is configured to be movable in the crosswise direction X. Thus, from a viewpoint of satisfying both the smooth texture and the prevention of chafing of the skin, the extending direction (longitudinal direction Yin FIG. 3) of the region 14 in which the laminated part 1 extends is preferably different from a direction in which the laminated part 1 can move (X direction in FIG. 3).

In the plane view of the nonwoven fabric 10, a region 15 of the single-layer part 7 surrounded by the laminated parts 1 is preferably present. The single-layer part 7 is surrounded by the laminated parts 1, whereby the movable action of the laminated part 1 with the single-layer part 7 as the starting point can easily occur. While the plurality of laminated parts 1 surrounding the single-layer part 7 is independently movable, the laminated parts can move in following the skin in a cooperative manner. Thus, the prevention of chafing of the skin in contact with the surface of the nonwoven fabric can be further improved.

In addition thereto, the region 15 of the single-layer part 7 surrounded by the laminated parts 1 preferably has a curved portion 15A in an outer edge in the plane view. In FIG. 3, the curved portion 15A has a plane shape curved in a U-shape. However, the curved portion 15A can take various curved shapes without being limited to the shape shown in FIG. 3.

The region 15 of the single-layer part 7 has the curved portion 15A, whereby the laminated part 1 can more smoothly move, and chafing of the skin can be further suppressed.

Aboundary between the single-layer part 7 and the laminated part 1 in the curved portion 15A is preferably arranged on the second surface side 72 of the nonwoven fabric 10. Thus, a step of the boundary between the single-layer part 7 and the laminated part 1 in the curved portion 15A is to be arranged on the second surface side 72 of the nonwoven fabric 10, whereby the smooth texture on the first surface side Z1 can be held.

{0044} In each region 14 in which the laminated part 1 extends in a certain direction, all may have a width same as or different from each other. In addition thereto, separately from the region 15 of the single-layer part 7, another single-layer part (not shown) along the extending direction of the region 14 may be further present in the region 14.

Fibres in the region 14 in which the laminated part 1 extends in one direction preferably exhibit the same orientation direction on at least one side of the first surface side 71 and the second surface side 72 of the nonwoven fabric 10. The laminated part 1 constituting the movable region 5 exhibits a fixed orientation direction, whereby the smoother texture can be obtained.

From this viewpoint, fibres in the first surface layer 2 in the laminated part 1 preferably exhibit the same orientation direction in each region 14 in which the laminated part 1 extends. In particular, the orientation direction of the fibres in the first surface layer 2 is preferably in a direction (longitudinal direction Y in FIG. 3) perpendicular to the direction in which the laminated part 1 can move (crosswise direction X in FIG. 3).

The fibres in the second surface layer 3 and the intermediate layer 4 of the laminated part 1 preferably exhibit the same orientation direction in each region 14 in which the laminated part 1 extends. In particular, the orientation direction of the fibres in the second surface layer 3 and the intermediate layer 4 preferably is in a direction perpendicular to the orientation direction of the fibres of the first surface layer 2, namely, the direction in which the laminated part 1 can move, from a viewpoint of improving the movability of the laminated part 1. {0046} The fibres in the first surface layer 2 in the laminated part 1 and the fibres in the single-layer part 7 preferably exhibit the same orientation direction. Thus, 10 the smoother texture can be obtained on the first surface side Z1 of the nonwoven fabric 10.

As described above, the expression "the fibres exhibit the same orientation direction" means that the ratio of the number of fibres P3 to the number of fibres P4 (the number of fibres P3 / the number of fibres P4) is 1.2 or more in each portion to be compared. The ratio is preferably 1.5 or more, and more preferably 2 or more in each portion to be compared.

The number of fibres P3 is the number of fibres crossing with two sides in one direction of a virtual square when the virtual square is arranged in observing a surface of an object part of the nonwoven fabric 10 along a plane direction.

The number of fibres P4 is the number of fibres crossing with two sides in the other direction of the virtual square.

At this time, an angle of each side of the square is not changed relative to the nonwoven fabric upon measurement between respective parts to be observed.

That is, the side of the square in which the first P3 is measured should be in parallel with the side of the square in which P3 is measured in another portion to be observed next. The number of fibres bigger than the other is specified as P3 and the other is specified as P4 in the first place amongst the three places.

The numbers of fibres P3 and P4 as described above can be measured according to the above-mentioned (method for measuring the numbers of fibres P1 and P2). The surface to be observed in the object part may be on any side of the first surface side 71 and the second surface side 72 in the object part.

A nonwoven fabric 20 for an absorbent article (hereinafter, referred to merely as a nonwoven fabric 20 in several cases) in a second embodiment will be described. Hereinafter, points different from the nonwoven fabric 10 for an absorbent article in the first embodiment will be described on the nonwoven fabric for an absorbent article in the second embodiment. In the nonwoven fabric 20 for an absorbent article in the second embodiment, the same sign is affixed and shown for a site or the like common with the nonwoven fabric 10 for an absorbent article in the first embodiment.

{0050} FIGs. 4 and 5 show the nonwoven fabric 20 in the second embodiment. The nonwoven fabric 20 in the second embodiment is different from the nonwoven fabric 10 in the first embodiment in arrangement of a laminated part 1 in a plane direction. With respect to other items, in the same manner as in the nonwoven fabric 10 in the first embodiment, the nonwoven fabric 20 in the second embodiment has a plurality of laminated parts 1, in which a first surface layer 2 and a second surface layer 3 are flat, and fibres in both the layers are oriented in the plane direction, and various preferable aspects described for the nonwoven fabric 10 in the first embodiment are appropriately applied thereto.

{0051} In the nonwoven fabric 20, as in a cross-sectional drawing shown in FIG. 4, a single-layer part 7 is arranged between the laminated parts 1 adjacent to each other. The nonwoven fabric 20 has, as the single-layer part 7, a single-layer part 71 on a first surface side 71 (hereinafter, also referred to as a top single-layer part 71) and a single-layer part 72 on a second surface side Z2 (hereinafter, also referred to as a back single-layer part 72). The top single-layer part 71 is continuous with the first surface layer 2 of the laminated part 1 to constitute a flat surface on the first surface side 71 of the nonwoven fabric 20. The back single-layer part 72 is continuous with the second surface layer 3 of the laminated part 1 to constitute a flat surface on the second surface side Z2 of the nonwoven fabric 20 In the nonwoven fabric 20, as in a plane drawing shown in FIG. 5, a region 21 in which the single-layer part 7 extends in a certain direction is preferably present. A region 22 in which the single-layer part 7 extends in one direction perpendicular to the certain direction is preferably present. Specific examples of the single-layer part 7 constituting the regions 21 and 22 include a top single-layer part 71. The certain direction and the direction perpendicular to the certain direction as described above are indicated as a longitudinal direction Y and a crosswise direction X in FIG. 5, respectively. However, the directions are not limited to these directions, and include various directions in a plane of the nonwoven fabric 20.

In the nonwoven fabric 20, at least any one of the region 21 and the region 22 in which the top single-layer part 71 extends is present, thereby resulting in uniformly aligning the top single-layer parts 7, whereby smooth texture can be more easily obtained without shaping a concavo-convex pattern. {0053} In a plane view of the nonwoven fabric 20, a region 23 of the laminated part 1 surrounded by the single-layer part 7 is preferably present. Specific examples of this aspect include presence of a region 23 of a laminated part 1 in a part surrounded by a region 21 and a region 22 in which a top single-layer part 71 extends. In this aspect, the regions 23 of the laminated parts 1 are regularly arranged separately at an equal interval in a lattice formed by perpendicularly intersecting the region 21 with the region 22 in which the top single-layer part 71 extends. This arrangement is formed into a structure for supporting the nonwoven fabric 20 as if the laminated parts 1 play a role as cobblestones relative to the whole of a plane surface of the nonwoven fabric 20. The laminated part 1 constitutes a movable region 5 in the same manner as in the first embodiment. Thus, the nonwoven fabric 20 can flexibly follow the plane of the nonwoven fabric 20 in all directions in meeting movement of the skin, whereby the prevention of chafing of the skin can be further improved. The plurality of laminated parts 1 forms a thickness to the whole of the plane of the nonwoven fabric 20, and acts as a soft spring to provide the nonwoven fabric 20 with cushioning properties.

Another region 24 of the single-layer part 7 is preferably further present in the region 23 of the laminated part 1. Specific examples of the single-layer part 7 constituting the region 24 include a back single-layer part 72. The plurality of laminated parts 1 acting as mentioned above easily moves in any direction at 360° with the region 24 of the single-layer part 7 as one of starting points, whereby the prevention of chafing of the skin can be further improved.

In the plane view of the nonwoven fabric 20, fibres in the single-layer part 7 extending in a certain direction and fibres in the single-layer part 7 extending in one direction perpendicular to the certain direction preferably exhibit the same orientation direction. Specifically, the fibres in the region 21 in which the top single-layer part 71 extends in the longitudinal direction Y and the fibres in the region 22 in which the top single-layer part 71 extends in the crosswise direction X preferably exhibit the same orientation direction. Thus, the first surface side Z1 of the nonwoven fabric 20 has the smoother texture. The expression "the fibres exhibit the same orientation direction" as used herein means the same content as described in the definition mentioned for the nonwoven fabric 10 in the first embodiment. The numbers of fibres P3 and P4 are also measured by the same method as mentioned above. The preferable range described in the first embodiment can also be applied thereto also in the second embodiment. {0056} As described above, the nonwoven fabric 10 for an absorbent article in the first embodiment and the nonwoven fabric 20 for an absorbent article in the second embodiment can be appropriately combined in a non-conflicting range with each other. For example, in the nonwoven fabric 20 for an absorbent article in the second embodiment, specific examples of a plane arrangement of the laminated parts 1 shown in a cross-sectional drawing in FIG. 4 include an aspect in which a region in which a laminated part 1 as in the first embodiment extends in one direction on a plane of a nonwoven fabric is arranged adjacent to a region 21 or a region 22 in which a single-layer part 7 extends (not shown).

In the nonwoven fabric 10 for an absorbent article in the first embodiment and the nonwoven fabric 20 for an absorbent article in the second embodiment, part of the laminated part 1 may be formed into a five-layer part. Specifically, there may be a material in which the intermediate layer 4 and a two-layer part of the second surface layer 3 in the laminated part 1 are laminated on another laminated part 1 adjacent thereto, thereby forming the five-layer part (not shown). Thus, the thickness increases and the cushioning properties are improved, whereby soft texture can be improved.

The nonwoven fabric 10 for an absorbent article in the first embodiment and the nonwoven fabric 20 for an absorbent article in the second embodiment can be produced by the method shown in FIG. 6, or the like. In FIG. 6, a support male material 120 and a support female material 130 for shaping a fibre web 110 before being processed into the nonwoven fabric are used. A nonwoven fabric precursor obtained by shaping is compressed in the thickness direction, whereby the nonwoven fabric is produced. Upon compressing the precursor in the thickness direction, operation is preferably performed while increasing temperature.

First, as shown in FIG. 6(A), the fibre web 110 is placed on the support male material 120 and pushed, and interposed with the support female material from above the fibre web 110 to shape the fibre web 110.

The support male material 120 has a plurality of projections 121 vertically rising on a base material. A place between the projections 121 and 121 is formed into a concave portion 122, and the concave portions 122 are arranged in a lattice shape.

The support female material 130 has the projections 131 that correspond to the concave portions 122 of the support male material 120. A place between the projections 131 and 131 is formed into a concave portion 132 corresponding to the projection 121 of the support male material 120. In the first embodiment, the nonwoven fabric 10 has a shape in which the projections 131 and the concave portions 132 are continuous in one direction in the plane view, and the projections 131 and the support concave portions 132 are alternately arranged in a direction perpendicular to the one direction. Specific examples thereof include a pattern of drum shape in which a plurality of ring-shaped disk is linked in a rotation axis direction at equal intervals. In the second embodiment, the projections 131 form the lattice shape, and the concave portions 132 are arranged inside the lattice shape.

In the support female material 130, a distance between the projections 131 and 131 is adjusted to be larger than the width of the projection 121 of the support male material 120. The distance is appropriately set so that a connecting portion 3 in which the fibre web 110 is interposed by the projection 121 of the support male material 120 and the projection 131 of the support female material 130 and the fibres are oriented in the thickness direction can be preferably shaped.

Blowing treatment by hot air W1 as shown in FIG. 6(B) is arbitrary applied by using the support male material 120 and the support female material 130 as described above. Next, the support female material 130 is removed, and hot air W2 as shown in FIG. 6(C) is blown to fuse the fibres to each other to be processed into the nonwoven fabric. Finally, the whole of the plane of the obtained nonwoven fabric precursor is compressed in the thickness direction, whereby the nonwoven fabric 10 for an absorbent article in the first embodiment and the nonwoven fabric 20 for an absorbent article in the second embodiment can be produced. Both the hot air W1 and the hot air W2 are not always required, and a blowing step of the first hot air W1 may be omitted and only the second hot air W2 may be blown thereto. Examples of the method of compressing the nonwoven fabric in the thickness direction include a method of pressing a nonwoven fabric to a calender roll, a method of applying tension to strongly wind the nonwoven fabric or a method of applying a load to compress the formed nonwoven fabric. Upon compressing the nonwoven fabric in the thickness direction, operation is preferably performed while increasing temperature. This temperature is adjusted to 30°C or more, whereby the nonwoven fabric is easily flattened, and an objective shape can be easily formed.

The nonwoven fabric for an absorbent article according to the present invention is not limited to the nonwoven fabric 10 for an absorbent article in the first embodiment and the nonwoven fabric 20 for an absorbent article in the second embodiment as described above. The nonwoven fabric for an absorbent article according to the present invention is one sheet of nonwoven fabric having thermoplastic fibres, and has the laminated part 1, including various aspects in which the first surface layer 2 and the second surface layer 3 are flat and the fibres in both the layers are oriented in the plane direction.

In the nonwoven fabric for an absorbent article according to the present invention, from a viewpoint of creating movement, an apparent thickness H1 under a load of 35 Pa (substantially no load) is preferably 0.5 mm or more, more preferably 1 mm or more, and further preferably 1.2 mm or more.

From a viewpoint of surface smoothness, the apparent thickness H1 under the load of 35 Pa is preferably 5 mm or less, more preferably 4 mm or less, and further preferably 3 mm or less.

The apparent thickness H1 under the load of 35 Pa is preferably 0.5 mm or more and 5 mm or less, more preferably 1 mm or more and 4 mm or less, and further preferably 1.2 mm or more and 3 mm or less.

{0065} The term "apparent thickness" in the present invention means a thickness between virtual planes in contact with outermost sites on the front and back surfaces of the nonwoven fabric for an absorbent article as a whole.

In the nonwoven fabric for an absorbent article according to the present invention, from a viewpoint of creating movement, an apparent thickness H2 under a load of 1 kPa (high load) is preferably 0.2 mm or more, more preferably 0.3 mm or more, and further preferably 0.5 mm or more.

From a viewpoint of surface smoothness, the apparent thickness H2 under the load of 1 kPa is preferably 3 mm or less, more preferably 2 mm or less, and further preferably 1.5 mm or less.

The apparent thickness H2 under the load of 1 kPa is preferably 0.2 mm 5 or more and 3 mm or less, more preferably 0.3 mm or more and 2 mm or less, and further preferably 0.5 mm or more and 1.5 mm or less.

In the nonwoven fabric for an absorbent article according to the present invention, from a viewpoint of surface smoothness, a ratio (H2/H1) of the apparent thickness H2 under the load of 1 kPa (high load) to the apparent thickness H1 under the load of 35 Pa (substantially no load) is preferably 10% or more, more preferably 20% or more, and further preferably 30% or more. As the ratio is larger, such a case is better, but the ratio is practically 80% or less. {0068} (Method for measuring apparent thickness of nonwoven fabric for absorbent article according to present invention) A measuring object nonwoven fabric is cut to 10 cm x 10 cm. When an area of 10 cm x 10 cm is unable to be taken, the nonwoven fabric is cut to a largest possible area. A thickness at the above load is measured by using a laser displacement sensor head (ZSLD80, manufactured by OMRON Corporation). Measurement is carried out in three places, and an average value is taken as the apparent thickness of the nonwoven fabric 10.

In addition thereto, from a viewpoint of improving action of the movable region 5, a ratio (E2/E1) of an area E2 of the laminated part 1 to the total area El of the nonwoven fabric for an absorbent article according to the present invention in the plane view is preferably 10% or more, more preferably 15% or more, and further preferably 20% or more. As the ratio is larger, such a case is better from a viewpoint of movement, but the ratio is practically 95% or less.

The nonwoven fabric for an absorbent article according to the present invention can be incorporated thereinto as various constituent members of the absorbent article by taking advantage of the smooth texture and the prevention of chafing of the skin. Specific examples of the absorbent article include an article used for absorbing a liquid excreted from a human body, such as a sanitary towel, a panty liner, a disposable nappy and an incontinence pad. The nonwoven fabric for an absorbent article according to the present invention is preferably used as a topsheet, a second sheet (sheet arranged between the topsheet and the absorbent body), an absorbent sheet, a covering sheet wrapping the absorbent body, a leak-proof sheet, or the like in the absorbent article.

Above all, the nonwoven fabric for an absorbent article according to the present invention is preferably processed into the absorbent article in which the nonwoven fabric is arranged as the topsheet by directing the first surface side toward the skin-facing surface side. The absorbent body is preferably arranged on the second surface side of the topsheet.

The constituent member of the absorbent article is pasted on the second surface side of the nonwoven fabric for an absorbent article according to the present invention, and an adhesive is preferably arranged in an area less than 70% of a whole surface on the second surface side of the nonwoven fabric for an absorbent article according to the present invention. Thus, the movable action of the laminated part 1 can be significantly exhibited together with the smooth texture on the first surface side of the nonwoven fabric for an absorbent article according to the present invention. From this viewpoint, a ratio of the area of the adhesive to the whole surface on the second surface side of the nonwoven fabric for an absorbent article according to the present invention is more preferably 65% or less, and further preferably 50% or less.

From a viewpoint of securing stability when the movable action of the laminated part 1 is exhibited, the ratio of the area of the adhesive to the whole surface on the second surface side of the nonwoven fabric for an absorbent article according to the present invention is preferably 10% or more, more preferably 15% or more, and further preferably 20% or more.

The ratio of the area of the adhesive to the whole surface on the second surface side of the nonwoven fabric for an absorbent article according to the present invention is preferably 10% or more and less than 70%, more preferably 15% or more and 65% or less, and further preferably 20% or more and 50% or less.

The absorbent article used for absorption of the fluid excreted from the body is typically provided with the topsheet, the backsheet, and a liquid-retainable absorbent body interposed between both sheets. As the absorbent body and the backsheet when the nonwoven fabric for an absorbent article according to the present invention is used as the topsheet, a material to be ordinarily used in the technical field can be used without particular restriction. For example, the absorbent article contains an absorbent core as the absorbent body, and arbitrarily contains a covering sheet wrapping the absorbent core. Specific examples of the absorbent core include a material prepared by holding a fibre aggregate formed of a fibre material such as pulp fibres or an aggregate of an absorbent polymer or a mixture thereof. As the covering sheet, tissue paper, the nonwoven fabric or the like can be used. As the backsheet, a film of a thermoplastic resin, or a liquid-impermeable or water-repellent sheet such as a laminate between the film and the nonwoven fabric can be used. The backsheet may have water-vapour permeability.

The absorbent article may be further provided with various members in corresponding to the specific application of the absorbent article. For example, when the absorbent article is applied to the disposable nappy or the sanitary towel, one pair or two or more pairs three-dimensional guards can be arranged in both right-left side portions on the topsheet.

Such an absorbent article having, as the constituent member, the nonwoven fabric for an absorbent article according to the present invention is processed into a folded state and distributed in the market. On the occasion, the absorbent article is formed into an absorbent article package housed in a packaging bag.

One specific example of this absorbent article package is a material in which a plurality of absorbent articles in a folded state is stacked and housed in one packaging bag.

Another specific example of the absorbent article package includes a material in which absorbent articles in a folded state are housed in an individual packaging bag one by one into an individual package, and a plurality of individual packages is further housed in one packaging bag.

In the absorbent article processed into the folded state, the nonwoven fabric of the absorbent article is preferably processed into the above-mentioned state shown as the nonwoven fabric for an absorbent article according to the present invention.

In the absorbent article package in which the plurality of absorbent articles is housed, the nonwoven fabric of the absorbent article is preferably processed into the state shown as the nonwoven fabric for an absorbent article according to the present invention.

EXAMPLES

Hereinafter, the present invention will be described more in detail with reference to Examples, but the present invention is not limited thereto. Terms "part" and "°/0" in the Examples is based on mass unless otherwise noted.

Presence or absence of plane orientation of fibres was confirmed based on the above-mentioned (Method for measuring the numbers of fibres P1 and P2). {0076}

(Example 1)

A nonwoven fabric precursor serving as a nonwoven fabric for an absorbent article corresponding to the first embodiment was prepared by using thermoplastic fibres having a fibre diameter shown in Table 1 according to a production method shown in FIG. 6. The nonwoven fabric precursor was cut into a size of 15 cm x 15 cm, and the resulting material was placed on a flat table, and an acrylic plate having an area larger than the area of the nonwoven fabric precursor was put thereon, and a weight of 20 kg was further put on the acrylic plate. In this state, the resulting assembly was left to stand at 50°C for one week to prepare a nonwoven fabric sample 1 for an absorbent article corresponding to the first embodiment.

The obtained nonwoven fabric sample 1 for an absorbent article had a laminated part, and basis weight in a first surface layer and a second surface layer, and presence or absence of fibre orientation in the laminated part were shown in Table 1.

(Example 2)

A nonwoven fabric sample 2 for an absorbent article corresponding to the second embodiment was prepared in the same manner as in Example 1 except that a nonwoven fabric precursor serving as a nonwoven fabric for an absorbent article corresponding to the second embodiment was prepared according to a production method shown in FIG. 6.

Basis weight in a first surface layer and a second surface layer, and presence or absence of fibre orientation in the obtained nonwoven fabric sample 2 for an absorbent article were shown in Table 1.

{0078} (Comparative Example 1) A nonwoven fabric sample Cl, a concavo-convex nonwoven fabric having a shape shown in FIG. 1 of Patent Literature 2 described above, was prepared by using thermoplastic fibres having a fibre diameter shown in Table 1 according to an air-through production method including a production step described in the paragraph [0031] of the specification of the same literature. Blowing treatment by first hot air W1 was applied thereto under conditions of a temperature of 160°C, an air speed of 54 m/s and a blowing time of 3 s. Blowing treatment by second hot air was applied thereto under conditions of a temperature of 160°C, an air speed of 6 m/s and a blowing time of 3 s.

Basis weight in a top portion of a first projecting portion on a first surface side, and a top portion of a second projecting portion on a second surface side, and presence or absence of fibre orientation in the obtained nonwoven fabric sample Cl were shown in Table 1.

{0079} (Comparative Example 2) A surface material of Merries tape type M size (Kao Corporation, 2018, manufactured in Japan) was peeled off after blowing a cold spray, and the obtained surface material was taken as a nonwoven fabric sample C2. Basis weight in a first surface layer and a second surface layer, and presence or absence of fibre orientation in the obtained nonwoven fabric sample C2 were shown in Table 1.

(Comparative Example 3) A nonwoven fabric was prepared by using thermoplastic fibres having a fibre diameter shown in Table 1 according to an air-through production method to prepare a flat nonwoven fabric sample C3 without performing concavo-convex shaping. Basis weight on a first surface side and a second surface side, and presence or absence of plane orientation of fibres in the nonwoven fabric sample C3 were shown in Table 1.

Tests (1) and (2) described below were conducted on the samples in Examples and Comparative Examples.

(1) Smoothness test Smooth texture was evaluated in terms of a friction coefficient. A surface roughness SMD value, a mean friction coefficient MIU value and a mean deviation MMD value of the friction coefficient were measured, by using Surface Tester KES-FB4 (trade name, manufactured by KATO TECH CO., LTD.), under conditions of SENS: 2 x 5 and a load: 4.9 kPa/m2, on a skin-facing surface side of each nonwoven fabric sample for an absorbent article. The surface roughness SMD value indicates that, as the value is smaller, the surface is smoother. The mean friction coefficient MIU value indicates slip resistance on the surface to indicate that, as the value is smaller, the surface is more slippery. The mean deviation MMD value of the friction coefficient indicates variation of friction to indicate that, as the value is smaller, coarseness on the surface is small and the surface is smoother. In particular, it is considered that an effect of smoothness depends on concavo-convex feeling felt by fingers. Therefore, as the SMD is smaller, the surface is felt to be smoother.

(4) Movement of first surface layer Movement of the first surface layer was measured by cutting the nonwoven fabric into 5 cm x 5 cm. A double-sided tape (NICETACK NWBB-15, manufactured by NICHIBAN CO., LTD.) was placed on a table in an area of 5 cm x 5 cm without any space. The cut nonwoven fabric was put thereon so that the second surface side of the nonwoven fabric may be brought into contact with the double-sided tape. Further, an acrylic plate having a size of 5 cm x 5 cm was stacked on the surface of the nonwoven fabric. The above-described double-sided tape was placed on the acrylic plate without any space, and the acrylic plate was put thereon so that the first surface side of the nonwoven fabric may be brought into contact with the double-sided tape. A load of 3 kPa was applied thereto from above the acrylic plate to adhere the nonwoven fabric with the double-sided tape. In this state, the acrylic plate was moved right and left, and a length at which the acrylic plate moved was measured. At this time, if an intermediate layer of the nonwoven fabric is present, the acrylic plate moves. The acrylic plate was moved up and down and right and left, and a length at which the acrylic plate moved most was measured.

{0083} Table 1

Example 1 Example 2 Comparative Comparative Comparative Example 1 Example 2 Example 3 Presence or absence of laminated part Presence Presence Absence Absence Absence First surface layer and second Flat Flat Absence Absence Absence surface layer in laminated part Plane orientation Presence Presence Absence Presence Presence Fibre diameter (dtex) 1.8 1.8 1.8 2.3 1.8 Basis weight (first surface side / 18/12 24/6 30/30 36 30 second surface side) (g/m2) (Same for all) (Same for all) KES smoothness: 1.965 2.370 2.500 5.090 2.185 Surface roughness SMD value KES smoothness: Mean friction coefficient MIU value 0.216 0.249 0.227 0.251 0.201 KES smoothness: 0.0082 0.0089 0.0082 0.0106 0.0066 Mean deviation MMD value of friction coefficient Movement of surface (mm) 3.0 3.5 1.1 0.9 0.3 *1) Basis weight (first surface side / second surface side) in Examples 1 and 2 indicated basis weight in the first surface layer / the second surface layer in the laminated part.

According to Table 1, in Examples 1 and 2, presence of the intermediate layer creates movement, and further a flat surface maintains smoothness. {0085} Having described our invention as related to this embodiments and Examples, it is our intention that the invention not be limited by any of the details of the description, unless otherwise specified, but rather be construed broadly within its spirit and scope as set out in the accompanying claims.

DESCRIPTION OF SYMBOLS {0086}

1 Laminated part 2 First surface layer 3 Second surface layer 4 Intermediate layer Movable region 6 Constricted portion 7 Single-layer part 10, 20 Nonwoven fabric for absorbent article Z1 First surface side 72 Second surface side

Claims

CLAIMS{Claim 1} A nonwoven fabric for an absorbent article comprising thermoplastic fibres, which comprises: a plurality of laminated parts in which one sheet of the nonwoven fabric is partially folded to form three or more layers overlapped in a thickness direction; wherein, in the laminated parts, a first surface layer positioned on a first surface side of the nonwoven fabric and a second surface layer positioned on a second surface side thereof are flat, and wherein fibres in the first surface layer and the second surface layer are oriented in a plane direction.{Claim 2} The nonwoven fabric for an absorbent article according to Claim 1, comprising a thermally fused pad between fibres in each layer of the nonwoven fabric; wherein the laminated part comprises a folding structure through no bonding means.{Claim 3} The nonwoven fabric for an absorbent article according to Claim 1 or 2, comprising a single-layer part between the laminated parts adjacent to each other in a plane view of the nonwoven fabric.{Claim 4} The nonwoven fabric for an absorbent article according to any one of Claims 1 to 3, wherein the first surface layer comprises a fibre of 2.4 dtex or less.{Claim 5} The nonwoven fabric for an absorbent article according to any one of Claims 1 to 4, wherein basis weight in the first surface layer is larger than basis weight in the second surface layer.{Claim 6} The nonwoven fabric for an absorbent article according to any one of Claims 1 to 5, comprising a plurality of regions in which the laminated part extends in a certain direction in a plane view of the nonwoven fabric.{Claim 7} The nonwoven fabric for an absorbent article according to any one of Claims 1 to 6, comprising a region of a single-layer part surrounded by the laminated part in a plane view of the nonwoven fabric.{Claim 8} The nonwoven fabric for an absorbent article according to Claim 7, wherein the region of the single-layer part comprises a curved portion in an outer edge in the plane view.{Claim 9} The nonwoven fabric for an absorbent article according to Claim 8, wherein a boundary between the single-layer part and the laminated part in the curved portion is arranged on the second surface side of the nonwoven fabric.{Claim 10} The nonwoven fabric for an absorbent article according to any one of Claims 6 to 9, wherein fibres in the region in which the laminated part extends in one direction exhibits the same orientation direction on at least one side of the first surface side and the second surface side of the nonwoven fabric.{Claim 11} The nonwoven fabric for an absorbent article according to any one of Claims 1 to 10, wherein fibres in the first surface layer of the laminated part and fibres in the single-layer part exhibit the same orientation direction.{Claim 12} The nonwoven fabric for an absorbent article according to any one of Claims 1 to 5, comprising a single-layer part between the laminated parts adjacent to each other in a plane view of the nonwoven fabric; wherein a region in which the single-layer part extends in a certain direction is present.{Claim 13} The nonwoven fabric for an absorbent article according to Claim 12, wherein a region in which the single-layer part extends in one direction perpendicular to the certain direction is present.{Claim 14} The nonwoven fabric for an absorbent article according to any one of Claims 1 to 5, 12 and 13, comprising a single-layer part; wherein a region of the laminated part surrounded by the single-layer parts is present in a plane view of the nonwoven fabric.{Claim 15} The nonwoven fabric for an absorbent article according to Claim 14, wherein another single-layer part is further present in the region of the laminated part surrounded by the single-layer parts.{Claim 16} The nonwoven fabric for an absorbent article according to Claim 13, wherein fibres in the single-layer part extending in the certain direction and fibres in the single-layer part extending in one direction perpendicular to the certain direction exhibit the same orientation direction.{Claim 17} The nonwoven fabric for an absorbent article according to any one of Claims 1 to 16, wherein the expression "the first surface layer or the second surface layer is flat" means that, upon placing the nonwoven fabric on a table with the first surface layer or the second surface layer on a lower side, and putting a transparent plate to be a load of 35 Pa on an upper side, a ratio of an area in contact with the transparent plate is at a predetermined level or more when viewed from above, and the ratio of the area in which the first surface layer or the second surface layer is in contact with the transparent plate is 50% or more and 99% or less, preferably 60% or more, and more preferably 70% or more, or preferably 95% or less, and more preferably 90% or less.{Claim 18} The nonwoven fabric for an absorbent article according to any one of Claims 1 to 17, wherein the expression "fibres in the first surface layer or the second surface layer are oriented in a plane direction" means an inequality: the number of fibres P1 > the number of fibres P2 holds in comparing the number of fibres P1 with the number of fibres P2, wherein the number of fibres P1 is the number of fibres crossing with each side of a virtual square when the virtual square is arranged in observing the nonwoven fabric for an absorbent article from the first surface side or the second surface side, and the number of fibres P2 is the number of fibres crossing with each side of a virtual square when the virtual square is arranged in observing a cross section of the first surface layer or the second surface layer along a thickness direction.{Claim 19} The nonwoven fabric for an absorbent article according to any one of Claims 1 to 18, wherein the expression "fibres in the first surface layer or the second surface layer are oriented in a plane direction" means that a ratio P1/P2 is 1.2 or more and 10 or less, preferably 1.5 or more, and more preferably 2 or more, or preferably 9 or less, and more preferably 8 or less with regard to the ratio of the number of fibres P1 to the number of the fibres P2, wherein the number of fibres P1 is the number of fibres crossing with each side of a virtual square when the virtual square is arranged in observing the nonwoven fabric for an absorbent article from the first surface side or the second surface side, and the number of fibres P2 is the number of fibres crossing with each side of a virtual square when the virtual square is arranged in observing a cross section of the first surface layer or the second surface layer along a thickness direction.{Claim 20} The nonwoven fabric for an absorbent article according to any one of Claims 1 to 19, wherein the first surface layer comprises a fibre of 0.2 dtex or more and 2.4 dtex or less, preferably 0.5 dtex or more, and more preferably 0.8 dtex or more, or preferably 2 dtex or less, and more preferably 1.8 dtex or less.{Claim 21} The nonwoven fabric for an absorbent article according to any one of Claims 1 to 20, wherein a ratio of basis weight G1 in the first surface layer to basis weight G2 in the second surface layer (basis weight G1 in the first surface layer / basis weight G2 in the second surface layer) is 1.2 or more and 10 or less, preferably 1.5 or more, and more preferably 2 or more, or preferably 8 or less, and more preferably 6 or less.{Claim 22} The nonwoven fabric for an absorbent article according to any one of Claims 10, 11 and 16, wherein the expression "fibres exhibit the same orientation direction" means that a ratio (the number of fibres P3 / the number of fibres P4) is 1.2 or more in each site to be compared, and preferably 1.5 or more, and more preferably 2 or more with regard to the ratio of the number of fibres P3 to the number of fibres P4, wherein the number of fibres P3 is the muber of fibres crossing with two sides in one direction of a virtual square when the virtual square is arranged in observing a surface of an object part of the nonwoven fabric for an absorbent article along a plane direction, and the number of fibres P4 is the number of fibres crossing with two sides in the other direction of the virtual square.{Claim 23} The nonwoven fabric for an absorbent article according to any one of Claims 1 to 22, wherein an apparent thickness H1 under a load of 35 Pa is 0.5 mm or more and 5 mm or less, preferably 1 mm or more, and more preferably 1.2 mm or more, or preferably 4 mm or less, and more preferably 3 mm or less.{Claim 24} The nonwoven fabric for an absorbent article according to any one of Claims 1 to 23, wherein an apparent thickness H2 under a load of 1 kPa is 0.2 mm or more and 3 mm or less, preferably 0.3 mm or more, and more preferably 0.5 mm or more, or preferably 2 mm or less, and more preferably 1.5 mm or less.{Claim 25} The nonwoven fabric for an absorbent article according to any one of Claims 1 to 24, wherein a ratio of an apparent thickness H2 under a load of 1 kPa to an apparent thickness H1 under a load of 35 Pa is 10% or more and 80% or less, preferably 20% or more, and more preferably 30% or more.{Claim 26} The nonwoven fabric for an absorbent article according to any one of Claims 1 to 25, wherein a ratio of an area E2 of the laminated part to a total area El of the nonwoven fabric for an absorbent article in a plane view is 10% or more and 95% or less, preferably 15% or more, and more preferably 20% or more.{Claim 27} The nonwoven fabric for an absorbent article according to any one of Claims 1 to 26, wherein part of the laminated part is formed into a five-layer part.{Claim 28} The nonwoven fabric for an absorbent article according to any one of Claims 1 to 27, wherein, in the laminated part, a constricted portion is arranged in 20 one or more selected from a connecting part between an end portion of the first surface layer and one end portion of an intermediate layer between the first surface layer and the second surface layer, a connecting part between an end portion of the second surface layer and the end portion of the first surface layer, and a connecting part between the other end portion of the intermediate layer and the end portion of the second surface layer.{Claim 29} The nonwoven fabric for an absorbent article according to any one of Claims 1 to 28, wherein, in the laminated part, a space portion is arranged between the second surface layer, and, the intermediate layer between the first surface layer and the second surface layer.{Claim 30} An absorbent article using the nonwoven fabric for an absorbent article according to any one of Claims 1 to 29.{Claim 31} An absorbent article, comprising the nonwoven fabric for an absorbent article according to any one of Claims 1 to 29 as a topsheet by directing the first surface layer toward a skin-facing surface side, and an absorbent body on the second surface side of the topsheet.{Claim 32} An absorbent article, wherein a constituent member of the absorbent article is pasted on the second surface side of the nonwoven fabric for an absorbent article according to any one of Claims 1 to 29; wherein an adhesive is arranged in an area of less than 70% on a whole surface on the second surface side of the nonwoven fabric for an absorbent article; and wherein a ratio of the area of the adhesive to the whole surface on the second surface side of the nonwoven fabric for an absorbent article is preferably 65% or less, and more preferably 50% or less, or preferably 10% or more, more preferably 15% or more, and further preferably 20% or more.{Claim 33} An absorbent article, wherein a nonwoven fabric contained therein is in a state described in any one of Claims 1 to 32 in the absorbent article in a folded state.{Claim 34} An absorbent article, wherein a nonwoven fabric contained therein is in a state described in any one of Claims 1 to 32 in an absorbent article package in which a plurality of absorbent articles is housed.