JP2015173766A - Absorbent articles - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an absorbent article which can be designed to be thin and is soft and excellent in fitness to show a good wearing feeling.SOLUTION: An absorbent article 1 has a longitudinal direction expansion region Q in which all of a surface sheet 2, a back surface sheet 3, and an absorber 4 have expansion properties to allow the expansion in a longitudinal direction X in a central part in a lateral direction Y of an excretion part facing part C. The back surface sheet 3 and the absorber 4 are joined to each other in a region other than the longitudinal direction expansion region Q. An expansion rate at a load of 25 cN of an article lateral direction central part piece, cut out from the absorbent article, in the longitudinal direction X is 15% or more, and the expansion rate at a load of 25 cN of an article lateral direction side part piece, cut out from the absorbent article, in the longitudinal direction X is 10% or less.

Description

  The present invention relates to an absorbent article such as a sanitary napkin that is used by being fixed to clothes such as shorts.

  As an absorbent article, there is known a structure having a top sheet, a back sheet, and an absorbent body interposed between both sheets, and having an excretory part facing part disposed to face the liquid excretion part of the wearer. . In Patent Document 1, the main body having such a configuration and the left and right side portions along the longitudinal direction of the excretory part-facing portion of the main body are extended and folded downward along the edge of clothing such as underwear when worn. In a sanitary napkin having a flap, the corner region corresponding to the longitudinal front and rear end portions of the flap can extend more outward in the lateral direction than the portion of the napkin disposed along the lateral center line of the flap. It is described that by providing a zone having different extensibility and different extensibility, the stress of the flap when the napkin is placed on the wearer's underwear can be removed. The zones having different extensibility are provided by performing processing such as mechanical deformation, folding, and pleating on the corner region of the flap.

  Patent Document 2 describes that, for the same purpose as Patent Document 1, a sanitary napkin having a main body and a flap is provided with extensibility that can be extended in at least two directions within an xy plane. As a specific example, longitudinal extensibility is imparted to the longitudinal central portion of the main body corresponding to the excretory part-facing portion, and the flaps extend in the direction intersecting the longitudinal extensibility and not perpendicular to the longitudinal direction. A sanitary napkin imparted with possible extensibility is described.

  Further, in Patent Document 3, for the same purpose as Patent Document 1, the flap of a sanitary napkin having a main body and a flap is provided with a first stress reducing means comprising a slit or a notch, and the first stress reducing means. Providing a second stress reducing means. According to Patent Document 3, a “slit” is a narrow cut that is adjacent or nearly adjacent to each other without joining two edges of the material, and “notch” is a material or material A space, dent, or cavity along the edge of the laminate. Further, the second stress reducing means is a region that can extend larger than other portions in the vertical direction, and is provided by a method of performing waveform processing on a predetermined portion such as an edge of the flap.

Japanese National Publication No. 9-511929 Japanese translation of PCT publication No. 2002-508893 JP-T-2006-501928

  A thin and flat absorbent article is excellent in portability in a packaged state. However, such a so-called thin absorbent article tends to have poor fit to the wearer's body, and because of its low fit, gives the wearer anxiety in terms of liquid absorbency and leakproofness was there.

  Therefore, the present invention relates to an absorbent article that can be designed to be thin and that is flexible, has good fit, and has a good wearing feeling.

  The present invention comprises a top sheet, a back sheet, and an absorbent body interposed between the two sheets, and has an excretory part facing part disposed to face the liquid excretion part of the wearer, and from the abdomen side of the wearer In an absorbent article having a longitudinal direction extending to the back side via the excretory part facing part and a lateral direction perpendicular thereto, the top sheet, the back sheet, and the absorption are provided in the lateral central part of the excretion part facing part. Each of the bodies has a stretchable region in which the stretchable material is stretchable in the longitudinal direction, and the backsheet and the absorbent body are joined to each other in a region other than the longitudinally stretched region. When the rectangular article in plan view extending in the vertical direction through the center in the lateral direction of the excretory part-facing part is cut out from the absorbent article to obtain an article laterally central section, the article laterally central part 25 cN in the longitudinal direction of the section An elongation rate in heavy time is 15% or more, and a rectangular shape portion in plan view, which is located laterally outward from a portion corresponding to the central portion of the article in the lateral direction, is cut out from the absorbent article, and the lateral direction side of the article In the case of a partial section, this is an absorbent article having an elongation rate of 10% or less at 25 cN load in the longitudinal direction of the lateral section of the article.

  ADVANTAGE OF THE INVENTION According to this invention, the absorbent article which can be designed thinly and is flexible, is excellent in fitting property, and has a favorable feeling of wear is provided.

FIG. 1 is a plan view schematically showing a surface sheet side (skin facing surface) of a sanitary napkin that is an embodiment of the absorbent article of the present invention. FIG. 2 is a cross-sectional view schematically showing a cross section taken along line II of FIG. 3A is a plan view schematically showing the back sheet side (non-skin facing surface) of the sanitary napkin shown in FIG. 1, and FIG. 3B is the back sheet side of the sanitary napkin shown in FIG. It is a top view which shows typically other embodiment. 4 (a) is a perspective view schematically showing a state in which the sanitary shorts are worn, and FIG. 4 (b) is a sanitary napkin shown in FIG. 1 at the crotch portion of the sanitary shorts shown in FIG. 4 (a). It is a perspective view which shows typically a mode that these are mounted | worn in the state which fixed. FIG. 5 is a plan view schematically showing the skin facing surface side (facing surface facing the absorber) of the back sheet in the sanitary napkin shown in FIG. 1. FIG. 6 is a plan view schematically showing the skin facing surface side (facing surface with the surface sheet) of the absorbent body in the sanitary napkin shown in FIG. 1.

  Hereinafter, the absorbent article of the present invention will be described with reference to the drawings, taking a sanitary napkin (hereinafter also referred to as a napkin) as a preferred embodiment thereof as an example. The napkin 1 which is one Embodiment of the absorbent article of this invention is shown by FIGS. 1-3. The napkin 1 includes a top sheet 2 that forms a skin facing surface, a back sheet 3 that forms a non-skin facing surface, and an absorbent body 4 interposed between both sheets 2 and 3, and is formed in a vertically long shape. . The top sheet 2 has liquid permeability, and the back sheet 3 has liquid impermeability or liquid impermeability, that is, leak-proof.

  In this specification, the skin facing surface is a surface (side relatively close to the wearer's skin) that is directed to the skin side of the wearer in the wearing state in the napkin and its constituent members (for example, the absorbent body 4). The non-skin facing surface is a surface (a side relatively distant from the wearer's skin) directed to the side opposite to the wearer's skin side in the wearing state of the napkin and its constituent members.

  The napkin 1 is disposed on the abdomen side (front side) of the wearer rather than the excretion part facing part C disposed opposite to the liquid excretion part (vaginal opening or the like) of the wearer when worn. It has the front part F and the back part R distribute | arranged to a wearer's back side (rear side) rather than the excretion part opposing part C at the time of wear. The excretory part opposing part C is corresponded to the center part of the vertical direction X of the napkin 1. FIG. Moreover, the napkin 1 has the vertical direction X equivalent to a wearer's front-back direction at the time of wear, and the horizontal direction Y orthogonal to this. The vertical direction X is a direction extending from the wearer's ventral side (front part F) to the back side (rear part R) via the excretory part facing part C. In this specification, the “front” (front) of the napkin corresponds to the front (ventral side) of the napkin wearer, and the “rear” (back) of the napkin is the back (back side) of the napkin wearer. Corresponding to In addition, “when wearing” or “when wearing” as used herein means a state in which a normal appropriate wearing position (correct wearing position of the absorbent article) is maintained, and the absorbent article is displaced from the wearing position. It is not included when it is in the state of being.

  In the absorbent article of the present invention, the excretory part-facing part is generated when the absorbent article is folded into an individual packaging form when it does not have a wing part like the napkin 1 of the present embodiment. The two folding lines (not shown) crossing the absorbent article in the transverse direction (width direction of the absorbent article, Y direction in the figure) are counted from the front end in the longitudinal direction of the absorbent article. It is a region surrounded by the first fold curve and the second fold curve, and this region may be the central portion in the vertical direction when the absorbent article is divided into three in the vertical direction. Moreover, the excretion part opposing part of the absorbent article which has a wing part is the area | region which has a wing part in the vertical direction (the longitudinal direction of an absorbent article, the X direction in a figure) of an absorbent article, More specifically, a wing This is a region sandwiched between the base on one side in the vertical direction of the part and the base on the other side. The wing part is a member extending laterally outward from the absorbent main body including the top sheet, the back sheet, and the absorber, and is usually the vertical center of the absorbent main body or the vertical direction of the excretory part facing part. Are a pair of left and right members extending outward in the lateral direction from both side portions along the line.

  Each of the top sheet 2 and the back sheet 3 has a size larger than that of the absorbent body 4 and extends outward from the periphery of the absorbent body 4, and an adhesive, heat seal, and ultrasonic seal are formed at these extended portions. These are joined together by a known joining means such as a peripheral seal portion. The absorber 4 extends from the front portion F to the rear portion R, and has a rectangular shape that is long in the longitudinal direction X and rounded at the corners when viewed from above.

  On the surface sheet 2 side (skin-facing surface) of the napkin 1, an annular groove 5 is formed in which the surface sheet 2 and the absorber 4 are integrally recessed toward the back sheet 3 side. The groove | channel 5 can be formed in accordance with a conventional method by pressing processing with or without heat, or embossing, such as ultrasonic embossing. In the groove 5, the top sheet 2 and the absorber 4 are integrated by heat fusion or the like. The groove 5 is located at least in the excretory part facing part C and is formed symmetrically with respect to a vertical center line (not shown) that bisects the napkin 1 in the lateral direction Y. By forming the grooves 5, liquid diffusion in the planar direction of the absorber 4 is more effectively suppressed, and twisting (unintentional deformation) of the absorber 4 can be more effectively prevented. become.

  The back sheet 3 side (non-skin facing surface) of the napkin 1 is directed to the clothing side, such as the crotch portion of sanitary shorts when worn. On the back sheet 3 side of the napkin 1, as shown in FIG. 3A, an adhesive portion 6 that fixes the napkin 1 to clothing is provided. The adhesive part 6 is provided by applying a known adhesive such as a hot-melt adhesive. As shown in FIG. 3A, the adhesive portion 6 has a shape with a different aspect ratio in plan view, more specifically, a rectangular shape, and its longitudinal direction is made to coincide with the lateral direction Y of the napkin 1, thereby In the direction X, a plurality (two pieces) are provided with an interval exceeding the longitudinal length of the excretory part facing part C. In the embodiment shown in FIG. 3A, one adhesive portion 6 is provided in each of the front portion F and the rear portion R (vertical front and rear end portions), and is provided in the excretory portion facing portion C (vertical center portion). It is not done. The plurality (two) of adhesive portions 6 have the same shape and the same size. The adhesive part 6 is covered with a release sheet (not shown) made of a film, a nonwoven fabric, paper or the like before use.

  FIG. 3B shows another embodiment of the napkin 1 on the back sheet 3 side. The embodiment shown in FIG. 3 (a) and the embodiment shown in FIG. 3 (b) are different in the arrangement form of the adhesive portions 6. In the embodiment shown in FIG. 3 (b), the adhesive portion 6 is a napkin 1. A plurality (seven pieces) are provided intermittently at predetermined intervals in the vertical direction X over substantially the entire length of the back sheet 3 side. The plurality (seven) of the adhesive portions 6 have the same shape and the same size, and the intervals between the adhesive portions 6 and 6 adjacent to each other in the vertical direction X are uniform. In addition, in each figure of Fig.3 (a) and (b), the front part F, the excretion part opposing part C, and the back part R have shown the same position. Moreover, in the embodiment of both figures, although the stretchable area | region of the surface sheet 2, the back surface sheet 3, and the absorber 4 is the same, according to arrangement | positioning of the adhesion part 6, the embodiment of FIG.3 (b), The longitudinal extension region Q is narrower with respect to the longitudinal direction X.

  One of the main features of the napkin 1 is that when the longitudinal front and rear end portions of the napkin 1 are gripped and pulled in the longitudinal direction X, the stretchability in the longitudinal direction is not uniform in the whole napkin 1, and at least facing the excretory part In the part C (vertical center part), the center part in the horizontal direction Y is easier to extend in the vertical direction X than both side parts.

  More specifically, a rectangular portion in plan view having a longitudinal length of 90 mm and a lateral length of 10 mm that extends in the longitudinal direction X through the center in the lateral direction Y of the excretory part facing portion C is cut out from the napkin 1. When it is set as the cross section of the article in the lateral direction, the elongation percentage at the time of 25c load in the longitudinal direction X of the cross section in the horizontal direction of the article is 15% or more, preferably 15.5% or more, and more preferably 16%. The upper limit of the elongation rate is preferably 35%.

  Further, a rectangular portion in plan view having a longitudinal length of 90 mm and a lateral length of 10 mm, which is located outside the lateral direction Y of the portion corresponding to the central portion of the lateral direction of the article, is cut out from the napkin 1 and the lateral direction of the article. In the case of the direction side section, the elongation rate at the time of 25c load in the longitudinal direction X of the article side section is 10% or less, preferably 8% or less, more preferably 7.5% or less. Most preferably, the lateral section of the article in the lateral direction is not stretched, that is, the stretch rate is 0%, but is not limited thereto.

  In addition, when preparing the said article | item horizontal direction side piece, it cuts out from an absorbent article so that the side edge along the vertical direction of an absorbent article may be included in the outer edge of this piece. When the length (width) of the absorbent article in the lateral direction is not constant, for example, like the napkin 1 shown in FIG. A rectangular shape in plan view having a longitudinal length of 90 mm and a lateral length of 10 mm from the absorbent article so that a side edge at the longitudinal center of the narrow excretory part-facing part is included in the outer edge of the lateral section of the article. Cut out the part. Further, when the article is small and such a section cannot be cut out, the length in the vertical direction and the length in the horizontal direction may be appropriately reduced. In that case, the distance between chuck | zippers is adjusted in the measuring method of the elongation rate described below. When there is no portion where the absorber and the back sheet are joined in the cut section, the measurement is performed by setting the test piece so that the absorber and the back sheet are completely overlapped.

The elongation percentage of the slice cut out from the absorbent article is determined in the following manner. A test piece (article lateral center section or article lateral side section) is mounted between a pair of upper and lower chucks of a tensile tester (for example, A & D Tensilon Tensile Tester RTG-1310). At this time, the distance between chucks is set to 70 mm, and the fixing width of the test piece by the chuck is set to 10 mm for each of the upper and lower ends of the test piece. Then, the pair of chucks are moved away from each other so that the tensile speed is 100 mm / min, and the test piece is pulled in the longitudinal direction (longitudinal direction of the absorbent article), and the tensile load (maximum load) is 25 cN. At this point, the movement of the chuck is stopped to complete the tensile test, and the length P1 (unit: mm) of the test piece after the tensile test fixed between the chucks is measured. Calculate the elongation in the direction.
Elongation ratio (%) in the longitudinal direction of the test piece = [{P1-distance between chucks before tensile test (= 70 mm)} / 70] × 100

  And the napkin 1 is sanitary for the napkin 1 through the adhesive part 6 as usual because the extensibility in the vertical direction X is different between the central part and the side part in the horizontal direction Y. When the shorts are stretched in the longitudinal direction X (the wearer's front-rear direction) while being fixed to the inner surface (skin facing surface) of the crotch part of the shorts, the excretory part facing part C (the center in the longitudinal direction X) of the napkin 1 Part) is deformed convexly toward the wearer's crotch side to form a middle-high part 11. That is, when the napkin 1 is extended in the vertical direction X, width shrinkage (necking) occurs, and the central portion in the horizontal direction of the excretory part facing part C rises.

  FIG. 4A schematically shows the state of wearing the sanitary shorts, that is, the state of pulling the sanitary shorts to the crotch side through both feet. In general, the crotch part (crotch part) 90C of the sanitary shorts 90 is extended to a considerable extent in the process of pulling up the shorts 90 in the front-rear direction of the wearer, specifically 15% or more (usually 15 to 20%). At this time, wrinkles are generated in the laterally central portion of the crotch portion 90C due to distortion, whereby the laterally central portion of the crotch portion 90C is raised in a convex shape toward the wearer's skin side (upward), thereby forming a middle-high portion 91 Is done. The middle-high portion 91 fits the wearer's crotch shape when the shorts 90 is completely pulled up to the wearer's crotch side and the mounting is completed.

  The napkin 1 is intended to improve the fitting property in combination with the longitudinal elongation deformation of the crotch portion when the sanitary shorts are worn, as described above. The characteristic of the napkin 1 that “the center part differs from the side part” is to wear the laterally central part of the excretory part facing part C (the central part of the vertical direction X) using this “longitudinal extension deformation of the shorts crotch”. It was adopted to make it rise in a convex shape on the person's crotch side. That is, the napkin 1 is fixed to the inner surface (skin facing surface) of the crotch part 90C of the sanitary shorts 90 through the adhesive portion 6 (see FIG. 3) as usual, and as shown in FIG. 4 (b). When the shorts 90 are pulled up together with the napkin 1, the middle-high part 91 is formed in the laterally central part of the crotch part 90C by the longitudinal extension deformation of the crotch part 90C of the shorts 90. On the other hand, when the sanitary short 90 is pulled in the vertical direction, the napkin 1 has the excretory part facing part C due to the fact that “the longitudinal extensibility differs between the central part and the side part in the horizontal direction”. Bulges toward the wearer's skin and forms the middle-high portion 11. At this time, the part corresponding to the middle-high part 91 in the sanitary shorts 90 (the central part in the lateral direction Y in the excretory part facing part C) is promoted to protrude in a convex shape toward the wearer's crotch side (upward). Therefore, the middle-high part 11 of the napkin 1 is stably formed and maintained. Thus, the napkin 1 or the upper part 11 of the napkin 1 formed by raising the central portion in the lateral direction Y of the excretory part facing part C is curved and deformed in a convex shape upward. Compared with the case where the shape is like a saddle, which is a kind of harness, the slope is gentle.

  In the actual use situation, in other words, the middle-high portion 11 is formed only when the napkin 1 is fixed and worn on the sanitary shorts, and is not formed when not worn. That is, when the sanitary shorts to which the napkin 1 is fixed are pulled in the front-rear direction, the middle-high portion 11 is formed on the napkin 1. In the middle-high part 11, the skin facing surface side (surface sheet 2 side) and the non-skin facing surface side (back sheet 3 side) are both convex and smooth curves that are convex on the wearer's crotch side (upward). The outline is drawn. The substantial thickness of the napkin 1 in the middle-high portion 11 (the total thickness of the constituent members) is not substantially different from that in other portions other than the middle-high portion 11. The napkin 1 is a so-called thin napkin that is thin and flat when not worn, and is excellent in portability in a packaged state. When the napkin 1 is worn, the central portion in the lateral direction Y of the excretory part-facing part C protrudes convexly toward the wearer's crotch side and becomes the middle-high part 11, together with the crotch part of the sanitary shorts Fits flexibly into the wearer's crotch shape. Accordingly, the napkin 1 has a configuration that can be designed to be thin, but has excellent fit to the wearer's crotch and is less likely to form a gap with the wearer's skin when worn. Difficult to spread and excellent in leakproofness, which can give the wearer a sense of security.

  On the other hand, in the conventional napkin which does not have the characteristic that “the extensibility in the vertical direction is different between the central part and the side part in the horizontal direction” according to the present invention, it is fixed to the sanitary shorts and pulled in the front-rear direction. Even if it operates, the middle-high part 11 which protrudes to a wearer side will not be fully formed, or it will become a shape dented to the shorts side (non-skin opposing surface side). This is because in the conventional napkin excretion part facing part, necking is unlikely to occur at the center part in the width direction, and the center part in the lateral direction is recessed toward the non-skin facing surface side. Therefore, when a conventional napkin is fixed to a sanitary short according to a conventional method, even if the sanitary short is pulled up in the vertical direction and rises to the wearer's skin side, the conventional napkin is Since the bulge tends to bulge in the direction opposite to the bulge direction of the shorts, the respective bulge forces are offset and the effects of the present invention are hardly obtained.

  From the viewpoint of improving fit, the raised height of the middle-high portion 11 formed when the napkin 1 is worn is preferably 5 mm or more, more preferably 7 mm or more, and preferably 30 mm or less, more preferably 25 mm or less, more Specifically, it is preferably 5 mm or more and 30 mm or less, and more preferably 7 mm or more and 25 mm or less. The raised height of the middle-high part 11 is a height from the side edge along the vertical direction of the napkin 1 located outside the middle-high part 11 in the lateral direction Y, and is measured according to the following procedures 1 to 6.

<Measuring method of deformation amount in article thickness direction at the time of absorbent article extension>
Step 1: Sanitary shorts (Kao Co., Ltd., “Laurier Active Guard“ Odekake Mode B ”M size”, unused unwashed product), centering on the crotch part (crotch part) and the ventral end (crotch part) The test base fabric is prepared by cutting the front end in a lateral length of 40 mm, the back side (crotch rear end) in a lateral length of 60 mm, and a longitudinal total length of 260 mm. At that time, members such as the crotch cloth of the crotch part originally attached to the shorts and the shape retaining piece are not removed but are left on the test base cloth.
Procedure 2: Spread the test base fabric in a flat state in a natural state, draw a front reference line 20 mm forward from the front end of the crotch, and further a rear reference line 200 mm rearward from this front reference line (about 30 mm rearward from the rear end of the crotch) Pull.
Procedure 3: The absorbent article to be measured is placed on the skin facing surface of the test base fabric, and the non-skin facing surface (the back sheet side) of the excretory portion facing portion of the absorbent article is the skin facing surface of the crotch portion of the test base fabric And a load is applied with a rubber roller having a weight of 2 kg from the side of the absorbent article, and the absorbent article is fixed to the test base fabric through the adhesive portion. The rubber roller is slowly reciprocated once over the entire length of the absorbent article.

Procedure 4: The pair of upper and lower chucks of a tensile tester (for example, A & D Corporation Tensilon Tensile Tester RTG-1310) are adjusted to a horizontal state and the distance between chucks is set to 200 mm. The test base fabric on which the absorbent article is fixed is mounted between the chucks. At this time, the test base cloth is mounted between the chucks so that the lower end of the upper chuck matches the front reference line of the test base cloth and the upper end of the lower chuck matches the rear reference line of the test base cloth.
Procedure 5: The pair of chucks are moved away from each other so that the tensile speed is 100 mm / min, and the test base fabric is stretched by stretching in the front-rear direction (longitudinal direction of the absorbent article). The movement of the chuck is stopped at the time of increase (when the test base fabric is stretched by 15%), and the state (the stretched state of the test base fabric) is maintained.

Procedure 6: About the absorbent article of the state fixed to the test base fabric, the deformation | transformation amount of the thickness direction of the excretion part opposing part (vertical direction center part) is measured.
Specifically, when the central part in the lateral direction of the excretory part-facing part protrudes in a convex shape on the skin-facing surface side (surface sheet side) [when the absorbent article is raised on the crotch side (upper side) of the wearer Equivalent to, and a metal scale is applied to the tip of the raised portion so as to straddle the raised portion in the lateral direction and coincide with the tangential direction of the raised portion. The distance (bump amount) between the both side edges of the absorbent article located on both outer sides is measured using another single metal scale. The average value of the two measured values (unit: mm) measured in this way is defined as a raised height (amount of deformation in the article thickness direction) of the raised portion (corresponding to the middle-high portion 11), and expressed as plus (+).
In addition, the central portion in the lateral direction of the excretory part-facing part protrudes in a convex shape toward the non-skin-facing surface side, in other words, when the skin-facing surface side is concavely recessed to form a concave part [when the absorbent article is worn, (Corresponding to the case where it protrudes on the side opposite to the side (downward side)) from the skin facing surface side so that one metal scale is in contact with both side edges of the absorbent article located on both lateral sides of the recess. The distance between the metal scale and the bottom of the recess (the amount of the recess) is measured using another metal scale, and the measured value (unit: mm) is the depth of the recess (article (Deformation amount in the thickness direction) and expressed as minus (−).
When the raised portion or the recessed portion cannot be confirmed in the excretory portion facing portion, the deformation amount in the article thickness direction is set to zero.

  The longitudinal extension characteristic of the napkin 1 described above, that is, “the longitudinal extension is not uniform in the whole napkin 1, and at least the central part in the lateral direction Y in the excretory part facing part C (vertical central part). In order to express the characteristic that “is easier to extend in the longitudinal direction X than both sides”, a device on the structure of the napkin 1 is required. Specifically, the napkin 1 has extensibility in which the top sheet 2, the back sheet 3, and the absorbent body 4 can be extended in the vertical direction X at the central part in the lateral direction Y of the excretory part facing part C. The back sheet 3 and the absorber 4 are not joined to each other in the longitudinal extension region Q, and other regions other than the longitudinal extension region Q. Are joined together.

  FIG. 5 shows the back sheet 3 constituting the napkin 1. The back sheet 3 is partially stretched in the longitudinal direction X, and the stretched portion 30 is located at the center in the lateral direction Y of the excretory portion facing portion C. The stretched portion 30 in the embodiment shown in FIG. 5 exists not only in the excretory portion facing portion C but also in the central portion in the lateral direction Y of each of the front portion F and the rear portion R. The stretched portion 30 of the back sheet 3 is one of the constituent elements of the longitudinal stretch region Q (see FIG. 3), and the stretchability in the longitudinal direction X is enhanced compared to other parts of the back sheet 3. ing. The peripheral part of the back sheet 3 including the other parts other than the stretched part 30 in the back sheet 3, that is, the both side parts in the lateral direction Y and the front and rear end parts in the longitudinal direction X in the excretory part facing part C is vertically It may or may not have extensibility in the direction X. However, in order to more reliably induce the above-described “convex deformation of the central portion in the lateral direction Y of the excretory facing portion C toward the wearer's skin”, the stretching process on the back sheet 3 is performed at the center excluding the peripheral portion. It is preferable to apply only to the part, and it is preferable that the peripheral part of the back sheet 3 does not have the extensibility in the vertical direction X. In the napkin 1 as shown in FIG. 3A of the present embodiment, the stretched portion 30 is overlapped with the longitudinal extension region Q, and the stretched processing of the back sheet 3 is performed except for the longitudinal stretch region Q. The portion 30 is not provided, or the stretchability in the vertical direction X is lost at the portion overlapping the adhesive portion 6.

  The stretching process of the back sheet 3 can be performed by a known gear stretching method in which a pair of gears having tooth grooves meshing with each other is used and the gear is engaged with the sheet. The shape of the gear may be a pair of gear rolls (wave rolls) in which the tooth gaps are engaged in a gear shape, or may be a flat plate shape. A large number of rectangular shapes in the stretched portion 30 shown in FIG. 5 are marks (pressurized portions) pressed by the gear roll.

As the back sheet 3, those conventionally used in this type of absorbent article can be used without particular limitation, and examples thereof include a thermoplastic film, and this film may have moisture permeability. Further, as the back sheet 3, a liquid-impermeable nonwoven fabric such as a spunbond-meltblown-spunbond (SMS) nonwoven fabric can also be used. The basis weight of the back sheet 3 is preferably 22 g / m ² or more, more preferably 30 g / m ² or more, and preferably 60 g / m ² or less, more preferably 50 g / m ² or less, more specifically, Preferably it is 22-60 g / m < ² >, More preferably, it is 30-50 g / m < ² >.

  FIG. 6 shows the absorbent body 4 constituting the napkin 1. A slit forming region 41 is formed at the center of the absorbent body 4 in the longitudinal direction X. The slit forming region 41 is provided with a number of slits (cuts) 40 in a straight line in plan view that penetrate the absorber 4 in the thickness direction. The slit 40 is provided intermittently in the vertical direction X with its longitudinal direction coinciding with the horizontal direction Y. The slit forming region 41 of the absorbent body 4 is one of the constituent elements of the longitudinally extending region Q (see FIG. 3), and the stretchability in the longitudinal direction X is enhanced as compared with other parts of the absorbent body 4. Yes. Parts other than the slit forming region 41 in the absorbent body 4, that is, the front and rear end portions in the longitudinal direction X of the absorbent body 4 may or may not have the extensibility in the longitudinal direction X. good.

As the absorbent body 4, those conventionally used in this type of absorbent article can be used without any particular limitation. For example, a fiber aggregate such as wood pulp, hydrophilized synthetic fiber, or the like. Those having a particulate water-absorbing polymer held on the body can be used. The absorbent body 4 may be configured to include a liquid-retaining absorbent core made of the fiber assembly and the like, and a liquid-permeable core wrap sheet that covers the absorbent core. For example, water-permeable thin paper, various non-woven fabrics, and apertured films can be used. In addition, the absorbent body 4 is not the fiber assembly (laminated fiber body obtained by stacking fiber materials) but has a thickness compared to the fiber assembly from the viewpoint of thinning and low rigidity of the napkin 1A. A thin, low-rigidity absorbent sheet can also be used. This absorbent sheet is made by bonding between constituent fibers or between constituent fibers and the water-absorbing polymer through adhesive force generated in the water-absorbing polymer in a wet state or a binder such as an adhesive or adhesive fiber added separately. A sheet or the like can be preferably used. The basis weight of the absorbent core 4 is preferably 80 g / m ² or more, more preferably 120 g / m ² or more, and preferably 450 g / m ² or less, more preferably 380 g / m ² or less, and more specifically, Preferably it is 80-450 g / m < ² >, More preferably, it is 120-
380 g / m ² .

  The back sheet and the absorbent used in the present invention are not only sheet-like materials having partially different longitudinal extensibility, such as the back sheet 3 shown in FIG. 5 or the absorbent 4 shown in FIG. It is also possible to use a sheet-like material that has uniform elongation in the direction and extends uniformly in the longitudinal direction.

  As described above, the back sheet 3 and the absorbent body 4 are not joined to each other in the longitudinally extending region Q, and are joined to each other in regions other than the longitudinally extending region Q. More specifically, the back sheet 3 and the absorbent body 4 are joined to each other at the peripheral edge of the region where they overlap each other. In the napkin 1, the back sheet 3 has a larger area than the absorbent body 4 and absorbs it. Since the entire surface of the body 4 facing the back sheet 3 (non-skin facing surface) is covered with the back sheet 3, the back sheet 3 is joined at the peripheral edge of the absorbent body 4. In the region located inward from the peripheral edge (longitudinal extension region Q), the back sheet 3 and the absorber 4 are not joined to each other. If the back sheet 3 and the absorbent body 4 are bonded to each other in the longitudinal extension region Q, the stretchability in the longitudinal direction X of the longitudinal extension region Q may be hindered, and it may be difficult to form the middle-high portion 11. There is.

The top sheet 2 is one of the constituent elements of the longitudinally extending region Q (see FIG. 3), and a sheet-like material having extensibility in the longitudinal direction is preferably used. As the material of the surface sheet 2, those conventionally used in this type of absorbent article can be used without particular limitation. For example, a nonwoven fabric produced by the card method, an air-through nonwoven fabric, a spunbond nonwoven fabric, a meltblown nonwoven fabric, a span Various non-woven fabrics such as lace non-woven fabric and needle punched non-woven fabric; and films made liquid permeable by opening means. These non-woven fabrics and films may be subjected to a hydrophilization treatment using a hydrophilizing agent such as a surfactant, and are expanded by processing such as formation of slit-shaped apertures and widening. And flexibility may be enhanced. The basis weight of the top sheet 2 is preferably 12 g / m ² or more, more preferably 18 g / m ² or more, and preferably 85 g / m ² or less, more preferably 78 g / m ² or less, more specifically, Preferably it is 12-85 g / m < ² >, More preferably, it is 18-78 g / m < ² >.

  As the top sheet 2, “a first fiber layer containing heat-shrinkable fibers and a second fiber layer containing fibers that do not substantially heat shrink or fibers that do not substantially heat shrink at the shrinkage start temperature of the heat shrinkable fibers”. And the uneven sheet obtained by shrinking the first fiber layer by hot air treatment. In this concavo-convex sheet, the second fiber layer protrudes toward the wearer's skin at a portion other than the joint portion with the first fiber layer to form a convex portion, while the joint portion forms a concave portion. ing. When using an uneven | corrugated sheet | seat as the surface sheet 2, a 2nd fiber layer is made into the skin opposing surface side, and is turned to a wearer's skin side. Since the concavo-convex sheet is manufactured as described above, it has elasticity in both the vertical direction and the horizontal direction. The heat-shrinkable fiber is preferably a latent crimpable fiber. Examples of such a concavo-convex sheet are described in JP 2002-187228 A, JP 2003-250836 A, JP 2004-166849 A, JP 2004-202890 A, JP 2009-153734 A, and the like. Can be used.

  The latent crimpable fibers are those that develop coiled crimps by heat treatment, for example, an eccentric core-sheath type composite fiber or side-by-side composite containing two types of thermoplastic polymer materials having different shrinkage rates. -Made of side type composite fiber. Examples thereof include those described in JP-A-9-296325 and JP2759331A. As the constituent fiber of the second fiber layer, a fiber made of a thermoplastic polymer material is preferably used. Examples of the thermoplastic polymer material include polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate, and polyamides. A core-sheath type or side-by-side type composite fiber made of a combination of these thermoplastic polymer materials can also be used.

  It is also effective to devise the material and arrangement of the adhesive portion 6 in order to more surely develop the longitudinal extension characteristics of the napkin 1 described above and to further ensure the formation of the middle and high portions 11 when worn. is there. That is, if the adhesive material having no stretchability in the vertical direction is used as the adhesive portion 6 and disposed on the entire surface of the back sheet 3, the longitudinal stretchability of the back sheet 3 is impaired and the napkin forms the middle and high portions 11. It becomes difficult to do. Therefore, the adhesive part 6 is arranged such that an adhesive material having an elastic property is stretchable in the longitudinal direction X, or as shown in FIG. 3A, the longitudinally extending region Q on the back sheet 3 side. It is preferable that it is provided outside in the longitudinal direction X of FIG. 3 or intermittently provided in the longitudinal direction X in the longitudinal extension region Q on the back sheet 3 side, as shown in FIG. Moreover, if the adhesive part 6 is provided in the whole area of the longitudinal extension region Q on the back sheet 3 side regardless of the presence or absence of the adhesive material, the extension of the longitudinal extension region Q in the longitudinal direction X is obstructed. As a result, the formation of the middle-high portion 11 may be difficult. In order to exhibit the effect of the present invention more effectively, the adhesive portion 6 is provided in a region including the center in the lateral direction Y of the excretory portion facing portion C of the back sheet 3 as in the embodiment shown in FIG. A form in which the adhesive portion 6 is provided only in the front and rear region in the longitudinal direction X without providing it is preferable. In addition, in the embodiment shown in FIG. 3A, if the back sheet 3 is moisture permeable, the moisture permeability is improved when the portion of the back sheet 3 where the adhesive portion 6 is not provided extends in the longitudinal direction X. From the viewpoint of suppressing stuffiness.

  As mentioned above, although this invention was demonstrated based on the preferable embodiment, this invention is not restrict | limited to the said embodiment. In addition to the sanitary napkin, the absorbent article of the present invention includes panty liners (orimono sheets), light incontinence pads, and the like. The following additional notes are disclosed with respect to the embodiment of the present invention described above.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to such examples.

[Example 1]
A sanitary napkin having the same basic configuration as the napkin 1 shown in FIGS. 1 to 3 was produced.
As a surface sheet, using an uneven sheet (basis weight 74 g / m ²⁾ described in JP-A-2009-153734. The concavo-convex sheet is one in which the entire sheet extends uniformly in the vertical and horizontal directions. Moreover, the polyethylene film by which the extending | stretching process was given partially with the structure similar to the back surface sheet 3 shown in FIG. 5 by the method mentioned later was manufactured, and this film was used as a back surface sheet.
As the absorber, an absorbent sheet produced by the method described in JP-A-8-246395 was used. Each of the absorbent sheets has an upper layer and a lower layer having a basis weight of 50 g / m ² , and a particulate water-absorbing polymer (made by Nippon Shokubai Co., Ltd., trade name “AQUALIC”) is interposed between the upper layer and the lower layer. It is sprayed at a basis weight of 50 g / m ² . This absorbent sheet is cut into a longitudinal length of 140 mm and a lateral length of 50 mm, and the longitudinal front and rear ends are rounded like the absorbent body 4 shown in FIG. In addition, 13 slits having a length of 60 mm and a width of 30 mm were formed at equal intervals with a slit interval of 5 mm.
In the central part of the skin facing surface of the back sheet, the basis weight of hot melt adhesive is applied to a region other than the rectangular region (corresponding to the longitudinally elongated region) having a longitudinal length of 90 mm and a lateral length of 40 mm. After the spiral spray coating at 10 g / m ² , the absorbent body and the surface sheet are successively placed on the center of the skin facing surface of the back sheet, embossed from the surface sheet side, and the groove in the napkin 1 shown in FIG. An annular groove as shown in FIG. 5 was formed, and the entire circumference was sealed and cut by a conventional method to obtain an absorptive main body having a longitudinal length of 170 mm and a lateral length of 75 mm. On the outer surface (non-skin facing surface) of the back sheet of the absorbent main body, two adhesive portions having a rectangular shape in a plan view are arranged at predetermined intervals (excretion portions) in the same manner as the adhesive portion 6 shown in FIG. A sanitary napkin was manufactured by providing a gap exceeding the longitudinal length of the facing portion. In Example 1, each adhesive portion has a longitudinal length of 10 mm, a lateral length of 50 mm, a basis weight of 50 g / m ² and is provided at a position spaced 20 mm inward in the longitudinal direction from the longitudinal end of the napkin. The interval between the two adhesive portions was 110 mm.

(Back sheet manufacturing method)
As a back sheet material, a low density polyethylene film having a basis weight of 23 g / m ² is used, and a groove having a rectangular shape in plan view is partially formed in the central portion of the film by the following method. The film was partially stretched in the longitudinal direction.
A wash plate-like pace plate was produced by carving a groove over the entire width of an aluminum plate having a length of 3 mm and a width of 150 mm on an aluminum plate having a total length of 250 mm, a width of 150 mm, and a thickness of 10 mm, with an inter-groove distance of 2 mm and a depth of 5 mm. . All the edge portions of the groove of the base plate were chamfered so that there were no corners.
A polyethylene foam material having a thickness of 2 mm is cut into a length of 90 mm and a width of 40 mm.
The film as a back sheet material is cut to a total length of 170 mm and a width of 75 mm, spread on the base plate and placed, and the polyethylene foam material is placed in the center. Further, a vinyl chloride resin plate having a total length of 250 mm, a width of 150 mm, and a thickness of 7 mm is placed on the polyethylene foam material, and a load is applied from above using a 5 kg rubber roller. When applying a load, a weight was applied to the rubber roller while pressing it against a vinyl chloride resin plate, and the load was applied so that the entire length of the polyethylene foam material was reciprocated three times. These operations were performed at room temperature.
By the above method, the low-density polyethylene film as the back sheet has a rectangular shape in plan view having a longitudinal length of 90 mm and a lateral length of 40 mm, excluding the peripheral edge of the film, corresponding to the groove of the base plate. In this area, a large number of grooves are intermittently formed in the vertical direction to form irregularities, and a stretched portion is formed. In this way, a back sheet that was partially stretched in the vertical direction (unevenness shaping) was produced.

[Example 2]
A sanitary napkin was produced in the same manner as in Example 1 except that the entire stretchable absorbent sheet produced in the following manner was used as the absorbent body (absorbent sheet).
70% by mass of heat-crimpable fibers similar to those used for the top sheet and 30% by mass of non-crimped core-sheath type composite fibers (core part is polyethylene terephthalate, sheath part is polyethylene, 2.2 dtex) A fiber web is prepared, and a particulate water-absorbing polymer (made by Nippon Shokubai Co., Ltd., trade name “AQUALIC”) is uniformly sprayed on the entire fiber web, and then the fiber web is thermally shrunk using a hot air dryer. A full surface stretchable absorbent sheet having a fiber basis weight of 120 g / m ² and a water absorbent polymer basis weight of 50 g / m ² was produced.

Example 3
A sanitary napkin was produced in the same manner as in Example 1 except that the entire back sheet was stretched in the longitudinal direction. In order to stretch the entire back sheet in the vertical direction, the same size as the back sheet was used as the pressing form for uneven shaping.

Example 4
A sanitary napkin was produced in the same manner as in Example 1 except that the arrangement of the adhesive portion was as shown in FIG. In Example 4, 31 adhesive portions were intermittently provided at intervals of 2 mm at the central portion in the horizontal direction of the central region in the vertical direction on the outer surface of the back sheet (excluding the region within 20 mm from the longitudinal front and rear end portions of the napkin). Each pressure-sensitive adhesive part had a longitudinal length of 2 mm, a lateral length of 50 mm, and a basis weight of 50 g / m ² .

Example 5
A sanitary napkin was produced in the same manner as in Example 1 except that the arrangement of the adhesive part was changed. In Example 5, the longitudinal length is 130 mm and the lateral length is in the lateral central portion of the longitudinal central region (excluding the region within 20 mm from the longitudinal front and rear end portions of the napkin) on the outer surface of the back sheet. ^Two strip-shaped adhesive portions with a basis weight of 20 g and a basis weight of 50 g / m 2 were provided at a distance of 15 mm in the lateral direction.

[Comparative Example 1]
A sanitary napkin was produced in the same manner as in Example 1 except that the arrangement of the adhesive part was changed. In Comparative Example 1, the center in the horizontal direction (the length in the vertical direction is 130 mm, the length in the horizontal direction is 50 mm) in the vertical center region (the region excluding the region within 20 mm from the longitudinal front and rear ends of the napkin) on the outer surface of the back sheet. The adhesive portion having a basis weight of 50 g / m ² was provided over the entire area of the rectangular shape in plan view. The used adhesive material is inelastic.

[Comparative Example 2]
A sanitary napkin was produced in the same manner as in Example 1 except that the absorbent sheet used as the absorbent was not provided with a slit.

[Comparative Example 3]
A sanitary napkin was produced in the same manner as in Example 1 except that the back sheet was not stretched.

[Evaluation]
For the sanitary napkins of Examples and Comparative Examples, the elongation rate at the time of 25c load and the article thickness change amount in the longitudinal direction of each of the article lateral direction central section and the article lateral direction side section are measured by the above method, respectively. The article elongation rate, fit feeling and softness were evaluated by the following methods. The results are shown in Table 1 below.

<Measuring method of article elongation rate>
In <Measurement method of deformation amount in article thickness direction when absorbent article is stretched>, when the test base fabric is in the stretched state according to step 5, the longitudinal direction of the sanitary napkin fixed to the test base fabric is measured. The full length P2 (unit: mm) is measured, and the article elongation rate is calculated by the following formula.
Article elongation ratio (%) = [(P2-full length of sanitary napkin before tensile test) / full length of sanitary napkin before tensile test] × 100

<Fitness and softness evaluation method>
Three sanitary napkins to be evaluated and a commercially available sanitary shorts (manufactured by Kao Corporation, “Lorrie Active Guard“ Odekake Mode B ””, select the appropriate size for the monitor) After being worn as usual, the fit and softness of the sanitary napkin were evaluated according to the following evaluation criteria. For both fit and softness, the smaller the evaluation point (average value of all monitors), the higher the evaluation.
・ Fit evaluation criteria: “1 Good fit”, “2 Good fit”, “3
"Neither", "4 Slightly fit", "5 Bad fit"
・ Evaluation criteria of softness: “1 soft”, “2 slightly soft”, “3 cannot be said”, “4 slightly hard”, “5 hard”

  As shown in Table 1, when the napkin of each example was fixed to the sanitary shorts and attached, good results were obtained in the evaluation of fit and softness compared to the case of the napkin of each comparative example. ing. In particular, those excluding the peripheral portion including the central portion in the lateral direction of the excretory part-facing portion than those giving the extensibility in the vertical direction to the entire back sheet (Example 3) ( Examples 1, 2, 4, and 5) were better in both fit and softness. In addition, the form in which the adhesive part is not provided in the center part of the back sheet (Example 1) has a larger amount of change in the article thickness than that in which the adhesive part is intermittently arranged on the entire surface of the back sheet (Example 4). It can be said that it is easily deformed into a shape that fits more easily by the wearer's excretion part, and it can be expected to be advantageous in absorbing excrement.

1 Sanitary napkin (absorbent article)
2 Top sheet 3 Back sheet 30 Stretched part 4 Absorber 40 Slit 41 Slit formation area 5 Groove 6 Adhesive part 11 Middle and high part F Front part C Excretion part opposing part R Rear part Q Longitudinal extension area X Longitudinal direction Y Lateral direction

Claims (4)

A top sheet, a back sheet, and an absorbent body interposed between the two sheets, and having an excretory part facing part disposed to face the liquid excretion part of the wearer, and the excretion part facing part from the wearer's ventral side In an absorbent article having a longitudinal direction extending to the back side through a lateral direction perpendicular to the longitudinal direction,
In the central part in the horizontal direction of the excretory part-facing part, the top sheet, the back sheet and the absorber all have a stretchable property that can be stretched in the vertical direction,
The back sheet and the absorber are bonded to each other in a region other than the longitudinally extending region,
When the rectangular section in plan view extending in the vertical direction through the center in the lateral direction of the excretory part-facing part is cut out from the absorbent article and used as the article central section in the article lateral direction, The elongation rate at 25 cN load in the vertical direction is 15% or more,
In the case where a rectangular portion in plan view is cut out from the absorbent article in a laterally outward direction of a portion corresponding to the central portion of the article in the lateral direction, the lateral portion of the article is formed as a lateral portion of the article. An absorbent article having an elongation rate of 10% or less at a load of 25 cN in the longitudinal direction of the section.   The absorptive article according to claim 1 provided with the adhesion part which fixes said absorptive article to clothes in the longitudinal direction outside of said longitudinal direction extension field in said back sheet side.   The absorbent article according to claim 1, wherein adhesive parts for fixing the absorbent article to clothes are provided intermittently in the longitudinal direction in the longitudinally extending region on the back sheet side.   The back sheet is partially stretched in the vertical direction, and the stretched portion of the back sheet is located in the lateral center of the excretory part-facing part. The absorbent article according to one item.

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