JP2015027428A - Underpants-type disposable diaper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an underpants-type disposable diaper excellent in operability when tearing off a side seal part.SOLUTION: Elastic members 51a and 51b are bonded by an adhesive agent to a ventral part F and a back side part R in a stretched state. End parts 52a and 52b of the elastic members 51a and 51b and portions in the vicinity thereof are colored by a color different from the ground color of the ventral part F or the back side part R. The end parts 52a and 52b of the elastic members 51a and 51b do not reach a position of a side seal part 4, and thereby, elastic member non-arrangement areas 9a and 9b are formed between the side seal part 4 and the end parts 52a and 52b of the elastic members 51a and 51b. There is no adhesive agent for bonding the elastic members 51a and 51b in the elastic member non-arrangement areas 9a and 9b.

Description

  The present invention relates to a pants-type disposable diaper.

  Conventionally, as a pants-type disposable diaper, a crotch part including an absorbent body, a ventral part and a dorsal part extending from the crotch part to a wearer's ventral side and a dorsal side, respectively, A material in which a pair of side seal parts, a waist opening part, and a pair of leg opening parts are formed by joining both side edges and right and left side edges in the back side part is widely used. Generally, an elastic member is bonded and fixed to the ventral side portion and the back side portion in an extended state.

  In the pants-type disposable diaper, the side seal part is often formed wide due to its manufacturing process, such a wide side seal part contributes to a decrease in the appearance of the diaper, In particular, it tends to be a hindrance when giving an underwear-like appearance to diapers. Therefore, it is desirable that the width of the side seal portion is as narrow as possible. However, if the width of the side seal portion is narrowed, the visibility is likely to be lowered, so that the operability when peeling the side seal portion tends to be lowered.

  Further, when the width of the side seal portion is narrowed, the bonding strength tends to decrease, and the elastic member fixed at the side seal portion may be disconnected. To prevent the elastic member from coming off, move the position of the end of the elastic member from the side seal to the inner position in the lateral direction, and fix the end firmly at the inner position. It is effective to do.

  As a conventional technique in which the end portion of the elastic member is not positioned on the side seal portion, for example, techniques described in Patent Documents 1 and 2 are known. In Patent Document 1, a breaking strength changing portion is provided at a position inside the side seal portion in the belly side portion and the back side portion of the diaper, and a continuous elastic member is provided between the side seal portion and the breaking strength changing portion. A pant-type absorbent article is described in which no pitting is provided. Patent Document 2 describes that the waistline elastic member provided in the waistline portion of the pants-type disposable diaper may be provided in a part of the waistline direction without being provided over the entire circumference in the waistline direction. .

JP 2011-234847 A JP 2012-249943 A

  However, in each patent document mentioned above, examination about the problem of the fall of visibility which is easy to occur when a narrow side seal part is formed is not made.

  Therefore, the subject of this invention is providing the underpants type disposable diaper which can eliminate the fault which the prior art mentioned above has.

In the present invention, the crotch part, the abdominal side part and the back side part extending from the front and back of the crotch part, both side edges of the abdomen side part, and both side edges of the back side part are joined. A pants-type disposable diaper having a longitudinal direction corresponding to the wearer's front-rear direction and a lateral direction perpendicular to the wearer's longitudinal direction,
The side seal portion has a fusion portion that continuously extends along the longitudinal direction of the diaper, and the non-joint portion is substantially non-externally disposed laterally outward of the diaper from the fusion portion. Has become,
A plurality of elastic members are joined to the ventral portion and the dorsal side portion by an adhesive under an extended state,
The elastic member is colored in a color different from the background color of the abdominal side portion or the back side portion where the elastic member is disposed at least at the end portion located near the side seal portion and the vicinity thereof. And
At least a part of the elastic member has an end portion located near the side seal portion of the end portion that does not reach the position of the side seal portion. The elastic member non-arrangement region is formed between the side seal portion and the end portion of the elastic member.
In the elastic member non-arrangement region, a pants-type disposable diaper is provided in which an adhesive for joining the elastic member is absent.

  ADVANTAGE OF THE INVENTION According to this invention, the operativity at the time of peeling off the side seal part of a diaper becomes favorable, and it can replace a diaper easily.

FIG. 1 is a perspective view schematically showing one embodiment of a pants-type disposable diaper of the present invention. FIG. 2 is a plan view schematically showing an unfolded and extended state of the diaper shown in FIG. FIG. 3 is a cross-sectional view schematically showing a cross section taken along line II of FIG. FIG. 4 is a side view showing a state where the diaper shown in FIG. 1 is mounted. FIG. 5 is a partially broken perspective view schematically showing an elastic sheet used as an outer package of the diaper shown in FIG. FIG. 6 is a perspective view schematically showing a part of the manufacturing process of the diaper shown in FIG. FIG. 7 is a perspective view showing an apparatus suitably used for forming the side seal portion of the diaper shown in FIG. 8 (a) to 8 (c) are explanatory views for explaining how the side seal portion is formed at the same time when the diaper continuous body is divided using the apparatus shown in FIG. FIG. 9 is a view (a view corresponding to FIG. 8 (c)) showing another example of a method for manufacturing a pants-type disposable diaper using the apparatus shown in FIG. 7. FIG. 10 is a schematic view showing another sheet that is suitably used as the outer package of the diaper shown in FIG.

  Hereinafter, the present invention will be described based on preferred embodiments with reference to the drawings. The diaper 1 which is one embodiment of the pants-type disposable diaper of the present invention is disposed on the non-skin facing surface side of the absorbent main body 2 and the absorbent main body 2 as shown in FIGS. An exterior body 3 to which the main body 2 is fixed, and along the longitudinal direction X of the exterior body 3 at the side edges 3F, 3F and the back side R along the longitudinal direction X of the exterior body 3 at the ventral side F. A pants-type disposable diaper in which the side edges 3R, 3R are joined to form a pair of side seals 4, 4, a waist opening 5, and a pair of leg openings 6, 6.

  The diaper 1 has a longitudinal direction X corresponding to the wearer's front-rear direction and a lateral direction Y orthogonal to the wearer's front-rear direction in a plan view in an unfolded and extended state as shown in FIG. The diaper 1 has a crotch part M disposed in the crotch part when worn, and a ventral side part F and a back side part R extending from the front and back of the crotch part M in the front-rear direction of the wearer. The crotch part M is an area in which recessed portions for forming the leg openings 6 and 6 are formed at both side edges along the vertical direction X.

  In addition, in this specification, a skin opposing surface is a surface turned to a wearer's skin side at the time of wear of a disposable diaper in a disposable diaper or its component (for example, absorptive main part 2), and a non-skin opposing surface is It is a surface in the disposable diaper or a component thereof directed to the side opposite to the skin side (clothing side) when the disposable diaper is worn. Moreover, the vertical direction X corresponds to the direction (longitudinal direction) along the long side of the absorbent main body 2 which is a disposable diaper or its constituent member, and the horizontal direction Y is the absorbent main body 2 which is a disposable diaper or its constituent member. Matches the width direction of.

  As shown in FIG. 2, the absorbent main body 2 has a vertically long shape in which one direction (vertical direction X) is relatively long, and includes a topsheet 21 that forms a skin facing surface and a non-skin facing surface. A back sheet 22 to be formed and a liquid-retaining absorbent 23 interposed between the two sheets 21 and 22 are provided. The absorbent 23 has a shape that is long in the same direction as the longitudinal direction X. . The absorbent main body 2 has its longitudinal direction aligned with the longitudinal direction X of the diaper 1 in the unfolded and expanded state (the state shown in FIG. 2), and a known joining means (adhesive or the like) at the center of the outer package 3. It is joined by.

  As the top sheet 21, the back sheet 22, and the absorber 23 that constitute the absorbent main body 2, various types that are conventionally used in the technical field can be used without particular limitation. As the surface sheet 21, for example, a liquid permeable sheet such as various nonwoven fabrics or perforated films subjected to a hydrophilic treatment can be used. Moreover, as the back sheet 22, a liquid-impermeable material or a water-repellent material can be used. As the liquid-impermeable material, a resin film, a resin film having fine pores and moisture permeability, a laminate material of a resin film and a nonwoven fabric, and the like can be used. A composite nonwoven fabric having a multilayer structure composed of bond, meltblown, spunbond, or the like, a spunbond nonwoven fabric, a heat bond nonwoven fabric, an air-through nonwoven fabric, or the like can be used. As the absorbent body 23, an absorbent core comprising an absorbent core made of water-absorbing polymer particles and a fiber material such as pulp fiber can be used. The absorbent core is a core wrap sheet such as tissue paper. It may be coated.

  As shown in FIG. 2, side cuffs 24 and 24 made of a liquid-resistant or water-repellent and breathable sheet material are provided on both left and right sides of the absorbent main body 2 along the longitudinal direction X. . Each side cuff 24 stands up when the side cuff elastic member 25 arranged in an extended state along the free end contracts, and prevents the liquid from flowing out in the lateral direction Y. Here, the expanded and extended state means that the side seal part 4 is peeled off to make the diaper into an expanded state, and the expanded state of the diaper is extended by the elastic member of each part, so that the design dimensions (the influence of the elastic member is not at all). It means a state in which it is expanded until it becomes the same size as when it is expanded in a flat state in the excluded state.

  The exterior body 3 includes an elastic sheet 30 having a structure in which two sheets 31 and 32 are laminated. As shown in FIG. 2, the front and rear end portions in the longitudinal direction X of the exterior body 3 made of the stretchable sheet 30 are folded back to the skin facing surface side, and the two exterior bodies 3 facing each other by the folding back. 3, that is, between the two stretchable sheets 30, 30, a plurality of thread-like abdominal waist elastic members 51 a and back waist elastic members 51 b are joined and fixed with an adhesive in an extended state. . The waist elastic members 51a and 51b are bonded and fixed at least at both ends by an adhesive, and preferably bonded and fixed by an adhesive over the entire length in the longitudinal direction. As a result, a waist gather is formed along the opening end of the waist opening 5.

  The side seal portion 4 is formed by joining the outer layer sheet 31 and the inner layer sheet 32 constituting the exterior body 3 in a state where the edge portions thereof overlap each other, and has a fused portion 40 as shown in FIG. The fusion part 40 is formed by fusing the exterior body 3 constituting the abdominal side part F and the exterior body 3 constituting the back side part R in a state where the edges overlap. The fused part 40 extends continuously along the longitudinal direction X of the diaper 1. The fusion means that the outer package 3 containing a thermoplastic resin is joined in its molten state.

  In the side seal part 4 having the fused part 40, the non-joined part is substantially absent on the outer side in the lateral direction Y of the diaper 1 than the fused part 40. Thereby, there is an advantageous effect that the appearance of the diaper 1 is improved. “Substantially non-existing” not only means that there is no non-joined portion outward in the lateral direction Y from the fused portion 40, but also is unavoidable due to fluctuations in manufacturing conditions of the side seal portion. In particular, it is intended to allow the presence of a non-bonded portion having a very small width (for example, 1 mm or less).

  The side seal portion 4 preferably has a small thickness T1 (see FIG. 3) in addition to the fact that the non-joining portion is substantially absent. By reducing the thickness T1 of the side seal part 4, the side seal part 4 is made inconspicuous, and an appearance like underwear can be imparted to the diaper 1. However, if the thickness T1 is too small, the bonding strength of the side seal portion is lowered, and the side seal portion 4 may be unintentionally broken when the diaper 1 is worn. From this viewpoint, the thickness T1 of the side seal portion 4 is preferably 0.2 mm or more, more preferably 0.25 mm or more, and preferably 2 mm or less, more preferably 1.5 mm or less. More specifically, it is preferably 0.2 mm or more and 2 mm or less, and more preferably 0.25 mm or more and 1.5 mm or less. Thickness T1 of the side seal part is determined with no load at a magnification of 50 to 200 times by using a microscope (VHX-1000 manufactured by KEYENCE Inc.) or the like at three cross sections separated in the longitudinal direction in the side seal part of one diaper. Observing and obtaining the thickness of the measurement target part in each cross section, it can be obtained as an average value of the three thicknesses.

  A suitable method for manufacturing the side seal portion having the above-described configuration will be described later.

  As above-mentioned, the appearance like an underwear can be provided to the diaper 1 by making the side seal part 4 inconspicuous. However, if the side seal part 4 is less noticeable, the operability when the side seal part 4 is peeled off when the diaper 1 is discarded tends to be lowered. Therefore, the diaper of the present invention is devised to improve operability when the side seal portion 4 is peeled off. Specifically, as shown in FIG. 4, the waist elastic members 51 a and 51 b arranged along the opening end of the waist opening are end portions 52 a and 52 b positioned closer to the side seal portion 4 among the end portions. However, it does not reach the position of the side seal portion 4 and terminates at a position closer to the inside in the lateral direction Y than the side seal portion 4. Thereby, elastic member non-arrangement regions 9a and 9b are formed between the side seal portion 4 and the end portions 52a and 52b of the waist elastic members 51a and 51b. The elastic member non-arrangement regions 9a and 9b are formed on both the abdominal side F and the back side R of the diaper 1 with the side seal portion 4 interposed therebetween. The elastic member non-arrangement regions 9 a and 9 b are formed only in the upper region of the side seal portion 4 in the vertical direction X.

  In the elastic member non-arrangement regions 9 a and 9 b, there is no adhesive for joining the waist elastic members 51 a and 51 b to the folded portion of the exterior body 3. That is, in the elastic member non-arrangement regions 9a and 9b, both the waist elastic members 51a and 51b and the adhesive are absent. As a result, in the elastic member non-arranged regions 9a and 9b, no gathers due to the contraction of the waist elastic members 51a and 51b are formed, and the flat sheet form of the outer package 3 is maintained in the wearing state of the diaper 1. Has been. In contrast, the waist elastic members 51a and 51b are joined to the exterior body 3 by the adhesives 11a and 11b in the stretched state in the inner region in the lateral direction Y than the elastic member non-arranged regions 9a and 9b. Therefore, the gathers resulting from the contraction of the waist elastic members 51a and 51b are formed. Thus, since the gathers are not formed in the elastic member non-arrangement regions 9a and 9b, the position of the side seal portion 4 is easily visible. Further, the elastic member non-arranged regions 9a and 9b have a small thickness, while the inner region in the lateral direction Y is larger than the elastic member non-arranged regions 9a and 9b. The region to be torn can be easily recognized. As shown in FIG. 4, the adhesives 11 a and 11 b are elastic members 51 a and 51 b along the longitudinal direction X of the diaper 1 in the inner region in the lateral direction Y than the elastic member non-arrangement regions 9 a and 9 b. It is given intermittently at the position where is placed.

  Since no gathers are formed in the elastic member non-arrangement regions 9a and 9b and no adhesive is applied, when the diaper 1 is measured from the outside of the outer package 3, the elastic member non-arrangement regions 9a and 9b The brightness of 9b is different from that of other regions, particularly the regions adjacent to the elastic member non-arranged regions 9a and 9b. The brightness can be represented by, for example, an L value in the Lab color system. The L value takes a value from 0 to 100, and the larger the numerical value, the higher the brightness. When measuring the L value, an artificial skin is placed under the site to be measured. Since the artificial skin has a low L value and is dark, the lightness L1 of the elastic member non-arranged regions 9a and 9b, that is, the regions where the gathers are not formed, is low due to the artificial skin being seen through. . In other words, it looks dark. On the other hand, the brightness L2 of the area where the gathers, which are areas adjacent to the elastic member non-arrangement areas 9a and 9b, are high because the artificial skin is easily concealed by the gathers. In other words, it looks bright. Therefore, the ratio L2 / L1 between the lightness L1 of the elastic member non-arranged regions 9a and 9b and the lightness L2 of the region adjacent to the elastic member non-arranged regions 9a and 9b is more than 1. Due to this lightness difference, it is possible to easily recognize the region to be torn visually. In addition, due to the synergistic effect of the brightness difference and the tactile sensation difference described above, the region to be torn can be recognized more easily. The ratio L2 / L1 is preferably 1.02 or more, more preferably 1.04 or more, and is preferably 1.3 or less, more preferably 1.25 or less. Specifically, it is preferably 1.02 or more and 1.3 or less, and more preferably 1.04 or more and 1.25 or less. When measuring the lightness L value, the diaper 1 is expanded as a measurement sample by 1.6 times or 2.6 times in the Y direction with the inner end in the lateral direction Y of the left and right side seal parts 4 as a base point. In the case of adult diapers, they are stretched in the Y direction so as to have a circumference of 60 cm and 100 cm. Then, artificial skin (Burex Bioskin Plate Part No. P001-001 color number # 10) is placed inside the diaper 1, and the spectral color difference meter and the diaper 1 are placed from the outside of the diaper 1 so that external light does not enter. Close the measurement target part without gaps. As the spectral color difference meter, for example, an NF333 simple spectral color difference meter (Nippon Denshoku Industries Co., Ltd.) can be used. In this embodiment, the ratio L2 / L1 is greater than 1 when the diaper 1 is stretched 1.6 times in the Y direction, or when it is stretched 2.6 times, or in both cases. Preferably there is. The 1.6-fold extension generally corresponds to the degree of extension of the diaper when worn by the wearer of the shortest size in the applicable size range of the diaper. 2.6-fold elongation generally corresponds to the degree of elongation of the diaper when worn by the wearer of the longest size in the applicable size range of the diaper.

  Furthermore, in the present invention, in order to further improve the visibility of the side seal portion 4, the waist elastic members 51a and 51b are positioned at least near the side seal portion 4 in at least one of the ventral portion F and the back portion R. The end portions 52a and 52b and the vicinity thereof are colored in a color different from the ground color of the ventral side F or the back side R where the waist elastic members 51a and 51b are arranged. As a result, in addition to the brightness difference between the elastic member non-arranged regions 9a and 9b and the inner region in the lateral direction Y from the elastic member non-arranged regions 9a and 9b, the difference in contrast in these regions is also clear. Thus, due to the synergistic effect of the two, the region to be torn can be more easily recognized. For example, the ventral waist part elastic member 51a arranged on the ventral part F has at least the end part 52a and the vicinity thereof, preferably the whole region of the ventral waist part elastic member 51a constituting the ventral part F. It is colored in a color different from the ground color of the exterior body 3. On the other hand, regarding the back side portion R, the back side waist portion elastic member 51b disposed on the back side portion F has at least the end portion 52b and the vicinity thereof, or the entire area of the back side waist portion elastic member 51b. The outer body 3 constituting the back side R may be colored in a different color from the ground color, or it may not be. In this case, the waist elastic members 51a and 51b colored in a color different from the ground color of the ventral side F or the back side R are from the appearance of the diaper 1, that is, sandwich the waist elastic members 51a and 51b. The exterior body 3 is visible through the watermark.

  From the viewpoint of further enhancing the visibility of the side seal portion 4, the color difference between the colors of the waist elastic members 51a and 51b and the ground color of the exterior body 3 is [a value of exterior body−a value of elastic member]. The value is preferably 10 or more, and more preferably 15 or more.

  Furthermore, from the viewpoint of further improving the visibility of the side seal portion 4, the color of the abdominal waist elastic member 51 a disposed on the abdominal side F and the back waist elastic member disposed on the back side R It is also preferable that the color of 51b is different. In addition to the colors of the elastic members 51a and 51b being different, it is also preferable that these colors and the ground color of the exterior body 3 are different.

  The stretch sheet 30 constituting the exterior body 3 described above has a configuration in which a thread-like elastic filament is bonded to one surface of an extensible fiber layer mainly composed of non-elastic fibers. In this embodiment, as shown in FIG. 5, two sheets of an outer layer sheet 31 and an inner layer sheet 32 and a plurality of thread-like elastic filaments 33 sandwiched between both sheets 31 and 32 are included. ing. The sheets 31 and 32 are both “extensible fiber layers mainly composed of inelastic fibers” (illustration of inelastic fibers is omitted in FIG. 5). The content of the non-elastic fiber in each of the sheets 31 and 32 mainly composed of non-elastic fibers is preferably 90% by mass or more, more preferably 91% by mass or more, and may be 100% by mass. As shown in FIGS. 2 and 3, the sheet 31 forms the outer surface of the diaper 1, and the sheet 32 forms the inner surface of the diaper 1. The elastic filament 33 extends along the lateral direction Y of the diaper 1. Although not shown in FIGS. 1 and 2, the elastic filament 33 is disposed at least around the waist of the diaper 1, and is preferably disposed over the entire region in the longitudinal direction X of the diaper 1. Furthermore, the elastic filament 33 is disposed in a substantially non-stretched state.

  The outer layer sheet 31 and the inner layer sheet 32 are both extensible. The sheets 31 and 32 can be extended in the lateral direction Y, which is the direction in which the elastic filament 33 extends. Stretchable means (a) when the constituent fibers themselves of the sheets 31 and 32 are stretched, and (b) even if the constituent fibers themselves are not stretched, the fibers bonded at the intersections are separated or the fibers are This includes the case where the three-dimensional structure formed by a plurality of fibers is structurally changed due to bonding or the like, or the constituent fibers are broken, and the sheets 31 and 32 are extended as a whole.

  The outer layer sheet 31 and the inner layer sheet 32 may be already stretchable in the state of the original fabric before being joined to the elastic filament 33. Alternatively, it is not stretchable in the state of the original fabric before being joined to the elastic filament 33, but is processed so as to be stretchable after being joined to the elastic filament 33, and becomes stretchable. Also good. Specific methods for making the sheet stretchable include heat treatment, roll-to-roll stretching, bite-and-gap stretching with teeth and gears, and tensile stretching with a tenter. In view of a preferable manufacturing method of the stretchable sheet 30 to be described later, the sheets 31 and 32 are original because the transportability of the sheets 31 and 32 is improved when the elastic filament 33 is fused to the sheets 31 and 32. In the opposite state, it is preferably not stretchable.

  The outer layer sheet 31 and the inner layer sheet 32 are extensible and substantially inelastic. Elasticity is a property that can be stretched and contracts when released from the stretched force, and the sheets 31 and 32 do not have such a property. When the sheets 31 and 32 have elasticity, a fiber containing an elastic resin is required as a constituent fiber thereof, and the fiber containing the elastic resin tends to exhibit a sticky feeling that contributes to lowering the texture of the nonwoven fabric. Therefore, in this embodiment, the sheets 31 and 32 are made substantially inelastic to prevent the texture from being lowered.

  As will be described later, the elastic filament 33 is formed by being stretched in a state where the elastic resin is melted or softened. Each of the plurality of elastic filaments 33 is substantially continuous over the entire length of the stretchable sheet 30, that is, the entire length in the lateral direction Y of the exterior body 3. The plurality of elastic filaments 33 are arranged so as to extend in one direction, that is, the lateral direction Y without crossing each other. In the present invention, the elastic filaments 33 are allowed to cross unintentionally due to inevitable fluctuations in the manufacturing conditions of the stretchable sheet 30. The plurality of elastic filaments 33 may each extend linearly or may meander while meandering as long as they do not cross each other.

  As described above, the elastic filament 33 is joined to the outer layer sheet 31 and the inner layer sheet 32 in a substantially non-stretched state. Since the elastic filament 33 is not stretched, the stretchable sheet 30 is not relaxed (creeped) due to stretching, and the elastic filament 33 is bonded to the sheets 31 and 32 at the time of storing the original fabric or after processing such as stretching. There is an advantage that there is no decrease in stretchability. Further, there is no deformation due to the tightness of the wound-up raw material. Further, for example, when the elastic filament 33 is stretched twice and bonded to the sheets 31 and 32, if it is temporarily returned to 1.3 times the initial value, it can be stretched only 1.7 times from this state. However, when pasting is performed in a non-stretched state, the initial origin when the stretchable sheet is stretched is different, so that the stretchable length of the sheets 31, 32 or the maximum elongation of the elastic filament 33 is stretched. There is an advantage that becomes possible.

  The diameter of the elastic filament 33 is not particularly limited, but is preferably 10 μm or more, more preferably 20 μm or more, and preferably 200 μm or less, from the viewpoint of the balance between the texture of the stretchable sheet 30 and the productivity of the elastic filament 33. More preferably, it is 130 μm or less. More specifically, it is preferably 10 μm or more and 200 μm or less, and more preferably 20 μm or more and 130 μm or less.

  The elastic filament 33 may have a circular cross section, but in some cases may have an elliptical cross section. For example, when the elastic sheet 30 is manufactured in accordance with the description of JP 2008-17912 A which is a preferable method for manufacturing an elastic sheet, the cross section of the elastic filament 33 tends to be elliptical. In this case, in the stretchable sheet 30, the elastic filament 33 has an elliptical long axis in the same direction as the plane direction of the stretchable sheet 30 and a short axis in the same direction as the thickness direction of the stretchable sheet 30. Preferably they are arranged.

  The pitch of the adjacent elastic filaments 33 and 33 (the distance between the centers of the adjacent elastic filaments) is the diameter of the elastic filament 33 from the viewpoint of the stretchable sheet 30 exhibiting sufficient stretchability and good cloth-like texture. Is within the above-mentioned range, preferably 0.1 mm or more, more preferably 0.4 mm or more, and preferably 5 mm or less, more preferably 1 mm or less. More specifically, it is preferably 0.1 mm or more and 5 mm or less, and more preferably 0.4 mm or more and 1 mm or less.

  In the stretchable sheet 30, the plurality of elastic filaments 33 are joined to the outer layer sheet 31 and the inner layer sheet 32 over the entire length thereof. Here, “bonded over the entire length” does not require that all the fibers in contact with the elastic filament 33 (component fibers of the sheets 31 and 32) are bonded to the elastic filament 33. This means that the elastic filament 33 and the constituent fibers (non-elastic fibers) of the sheets 31 and 32 are bonded to the elastic filament 33 in such a manner that there is no intentionally formed non-bonded portion. Since the elastic filament 33 is bonded to each of the sheets 31 and 32 over the entire length, the bonding force between the elastic filament 33 and the sheets 31 and 32 can be sufficiently increased. As a result, even if the elastic sheet 30 is stretched, the elastic filament 33 is difficult to peel from the sheets 31 and 32. If the elastic filament 33 is peeled off from the sheets 31 and 32, in the natural state (relaxed state), floating occurs between the elastic filament 33 and the sheets 31 and 32, and wrinkles are easily generated in the stretchable sheet 30. The stretchable sheet 30 as a whole lacks a sense of unity.

  In the stretchable sheet 30, some of the many inelastic fibers contained in the outer layer sheet 31 and the inner layer sheet 32 are fused with the elastic filament 33 and buried in the elastic filament 33. The non-elastic fibers buried in the elastic filament 33 may be all or a part of the non-elastic fibers existing around the elastic filament 33. The term “buried” as used herein means that at the intersection of the inelastic fiber and the elastic filament 33, the portion of the inelastic fiber existing at the intersection is the portion of the elastic filament 33 existing at the intersection. A state that has been submerged. Therefore, the state in which the non-elastic fibers and the elastic filaments 33 are joined by dots or lines on their surfaces is not included in the burial according to the present invention. Further, from the viewpoint of improving the bonding strength between the non-elastic fiber and the elastic filament 33, the non-elastic fiber is preferably embedded in the elastic filament 33 with a degree of half or more of its diameter.

  The bonding strength between the elastic filament 33 and the non-elastic fibers contained in the outer layer sheet 31 and the inner layer sheet 32 is as described above, whereby the bonding strength between the elastic filament 33 and the sheets 31 and 32 is increased, and the elastic sheet. When 30 is extended, peeling between the two is less likely to occur. As a result, when the stretchable sheet 30 is stretched, the sheets 31 and 32 follow the stretch of the elastic filament 33 and stretch with good responsiveness. Therefore, there is an advantageous effect that the stretchability of the stretchable sheet 30 is improved. Is done. Further, since the elastic filament 33 and the non-elastic fibers included in the sheets 31 and 32 are joined as described above, the elastic filament 33 and the sheets 31 and 32 are in close contact with each other, and the presence of the elastic filament 33 is present. Since it is more difficult to feel the step between the portion that is present and the portion that is not present, there is also an advantageous effect that the texture of the stretchable sheet 30 is improved.

  When the elastic sheet 30 is manufactured according to the method described in Japanese Patent Application Laid-Open No. 2008-17912, which is a preferable method for manufacturing the elastic sheet 30, “the non-elastic fiber is fused with the elastic filament 33 and embedded in the elastic filament 33. State "is obtained. According to this manufacturing method, no heat is applied to the sheets 31 and 32, and the elastic filaments 33 are fused to the sheets 31 and 32 before the elastic filaments 33 obtained by melt spinning are solidified. Only the fibers existing around 33 are bonded to the elastic filament 33, and the fibers located further away from the fibers maintain the texture of the sheets 31 and 32. Therefore, the texture of the stretchable sheet 30 is good. There is an advantage that it is kept.

  As described above, the elastic filament 33 in the stretchable sheet 30 is joined to the sheets 31 and 32 by melting the elastic filament 33 in a state where the fibers (non-elastic fibers) constituting the sheets 31 and 32 are buried in the elastic filament 33. It was made by wearing, not using an adhesive such as a hot melt adhesive. Therefore, there is no adhesive between the sheets 31 and 32 (extensible fiber layer mainly composed of non-elastic fibers) and the elastic filaments 33 bonded thereto.

  The stretchable sheet 30 can be stretched in the same direction as the direction in which the elastic filament 33 extends (lateral direction Y). The stretchability of the stretchable sheet 30 is expressed due to the elasticity of the elastic filament 33. When the stretchable sheet 30 is stretched in the same direction as the direction in which the elastic filament 33 extends, the elastic filament 33 and the sheets 31 and 32 extend. When the stretching of the stretchable sheet 30 is released, the elastic filament 33 contracts, and the sheets 31 and 32 return to the state before stretching as the contraction occurs. Further, in the stretchable sheet 30, there is no other elastic filament bonded in a state orthogonal to the elastic filament 33. Therefore, the stretchable sheet 30 is stretched in the lateral direction Y, which is the direction in which the elastic filament 33 extends. In some cases, the stretchable sheet 30 stretches in the transverse direction Y with little so-called width shrinkage.

  The forming material of the stretchable sheet 30 will be described. As the fibers constituting the outer layer sheet 31 and the inner layer sheet 32 (extensible fiber layer mainly composed of inelastic fibers), substantially inelastic inelastic fibers are used. Specific examples include fibers made of polyester such as polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), polyamide, and the like. The fibers constituting the sheets 31 and 32 may be short fibers or long fibers, and may be hydrophilic or water repellent. Moreover, a core-sheath type or side-by-side type composite fiber, a split fiber, a modified cross-section fiber, a crimped fiber, a heat-shrinkable fiber, or the like can also be used. These fibers can be used alone or in combination of two or more.

  Each of the outer layer sheet 31 and the inner layer sheet 32 may be a continuous filament or a nonwoven fabric of short fibers. In particular, from the viewpoint of making the stretchable sheet 30 thick and bulky, the sheets 31 and 32 are preferably short fiber nonwoven fabrics. Examples of the nonwoven fabric include air-through nonwoven fabric, heat roll nonwoven fabric, spunlace nonwoven fabric, spunbond nonwoven fabric, and meltblown nonwoven fabric. The sheet 31 and the sheet 32 may be the same type or different types. As used herein, “same kind of sheet” means sheets having the same manufacturing process, the type of constituent fibers of the sheet, the fiber diameter and length of the constituent fibers, the thickness and basis weight of the sheets, etc. . If at least one of these is different, it is a “dissimilar sheet”.

  Each of the outer layer sheet 31 and the inner layer sheet 32 is preferably composed of two or more components of a low melting point component and a high melting point component. In that case, the constituent fibers are joined at fiber intersections by at least thermal fusion of the low melting point components. As the core-sheath type composite fiber composed of two or more components of a low melting point component and a high melting point component, those having a core of high melting point PET, PP and a sheath of low melting point PET, PP, PE are preferable. In particular, the use of these composite fibers is preferable because the fusion with the elastic filament 33 becomes strong and peeling between the two hardly occurs.

The thicknesses of the outer layer sheet 31 and the inner layer sheet 32 are each preferably 0.05 mm or more, more preferably 0.1 mm or more, and preferably 5 mm or less, more preferably 1 mm or less. More specifically, it is preferably 0.05 mm or more and 5 mm or less, and more preferably 0.1 mm or more and 1 mm or less. The thickness of the sheet is such that the sheet to be measured is sandwiched between flat plates with a load of 0.5 cN / cm ² , and cross sections of the sheet at three locations separated in the longitudinal direction in one diaper are microscopes (VHX manufactured by KEYENCE Corporation). 1000) and the like, and the thickness is obtained in each cross section, and can be obtained as an average value of three thicknesses. The basis weights of the sheets 31 and 32 are each preferably 3 g / m ² or more, more preferably 5 g / m ² or more, and preferably 100 g / m ² or less, from the viewpoints of texture, thickness, and design properties. More preferably, it is 30 g / m ² or less. More specifically, it is preferably 3 g / m ² or more and 100 g / m ² or less, more preferably 5 g / m ² or more and 30 g / m ² or less.

The basis weight of the plurality of elastic filaments 33 arranged between the sheets 31 and 32 (basis weight of the elastic filament layer) is preferably 3 g / m ² or more from the viewpoints of stretchability, texture, thickness, cost, and the like. Preferably it is 4 g / m ² or more, preferably 30 g / m ² or less, more preferably 15 g / m ² or less. More specifically, it is preferably 3 g / m ² or more and 30 g / m ² or less, more preferably 4 g / m ² or more and 15 g / m ² or less.

  The elastic filament 33 is made of, for example, a thermoplastic elastomer or rubber. In particular, when a thermoplastic elastomer is used as a raw material, it can be melt-spun using an extruder in the same manner as a normal thermoplastic resin, and the elastic filament thus obtained is easily heat-sealed. 30. Examples of the thermoplastic elastomer include styrene such as SBS (styrene-butadiene-styrene), SIS (styrene-isoprene-styrene), SEBS (styrene-ethylene-butadiene-styrene), and SEPS (styrene-ethylene-propylene-styrene). -Based elastomers, olefin-based elastomers (ethylene-based α-olefin elastomers, propylene-based elastomers copolymerized with ethylene, butene, octene, etc.), polyester-based elastomers, polyurethane-based elastomers, and the like. Two or more kinds can be used in combination. Further, core-sheath type or side-by-side type composite fibers made of these resins can also be used.

  In addition to the items described above, the items described in Japanese Patent Application Laid-Open No. 2008-17912 are appropriately applied to items related to the stretchable sheet 30.

  As described above, since the elastic filament 33 extends over the entire length of the diaper 1 in the lateral direction Y, the end of the elastic filament 33 reaches the side seal portion 4. Therefore, the elastic filament 33 exists in the elastic member non-arrangement regions 9a and 9b described above. However, since the elastic filament 33 is not bonded and fixed by an adhesive, it does not become a target of presence or absence of the elastic member non-arrangement regions 9a and 9b. Only the elastic member joined by the adhesive is subject to presence / absence in the elastic member non-arrangement regions 9a and 9b.

  The diaper 1 of this embodiment can be suitably manufactured, for example with the manufacturing method demonstrated below. The manufacturing method of the diaper 1 of the present embodiment is such that the exterior body continuous body on the abdomen F side and the exterior body continuous body on the back side R side are overlapped to obtain an exterior body continuous laminate, and the exterior body continuous laminate A step of forming the side seal portion 4 by fusing a portion where the side seal portion 4 is to be formed in the body.

  First, as shown in FIG. 6, on the inner layer sheet 32 in the strip-shaped exterior body 3 (the strip-shaped elastic sheet 30) (exterior body continuous body) continuously supplied from an original fabric roll (not shown), The absorbent body 2 manufactured separately according to the method is intermittently arranged and fixed. An adhesive such as a hot melt adhesive is applied in advance to the absorbent main body 2 and / or the inner layer sheet 32, and the absorbent main body 2 is fixed to the exterior body 3 (inner layer sheet 32) by the adhesive. Further, in parallel with the arrangement of the absorbent main body 2, both side portions 3 a along the width direction of the strip-shaped exterior body 3 in a stretched state in which the plurality of waist elastic members 51 a and 51 b are stretched to a predetermined stretch rate. , 3a. When the waist elastic members 51a and 51b are introduced, a hot melt adhesive is continuously or intermittently applied over the entire length of the waist elastic members 51a and 51b by an adhesive coating machine (not shown). However, the application of the adhesive is controlled so that the waist elastic members 51a and 51b are not bonded to either the outer layer sheet 31 or the inner layer sheet 32 in the side seal portion formation planned portion 110C described later.

  Next, as shown in FIG. 6, leg holes LH are formed at predetermined positions of the strip-shaped exterior body 3 in which the absorbent main body 2 and the waist elastic members 51 a and 51 b are arranged. This leg hole forming step can be carried out by using a technique similar to that in a conventional method for manufacturing this type of article, such as a rotary cutter and a laser cutter. In addition, you may implement a leg hole before arrangement | positioning instead of arrangement | positioning of the absorptive main body 2 like this embodiment.

  Next, the strip-shaped exterior body 3 is folded in the width direction (a direction perpendicular to the longitudinal direction of the strip-shaped exterior body 3) so that the abdomen side F side and the back side R side are overlapped. More specifically, as shown in FIG. 6, both side portions 3 a, 3 a along the longitudinal direction (conveying direction MD) of the strip-shaped exterior body 3 are folded back so as to cover the waist elastic member 51. Then, the exterior body 3 is folded in two along the width direction CD together with the absorbent main body 2. That is, the exterior body continuum on the ventral side F and the exterior body continuum on the back side R are overlapped. The longitudinal direction (conveying direction MD, Machine Direction) of the strip-shaped exterior body 3 coincides with the lateral direction Y of the diaper 1, and the width direction CD (Cross machine Direction) of the strip-shaped exterior body 3 is in the longitudinal direction X of the diaper 1. Match. Thus, a diaper continuous body 110 (exterior body continuous lamination) in which a plurality of precursors of diapers 1 (pants-type disposable diapers in which a pair of side seal portions 4 and 4 are not formed) is continuous in one direction (lateral direction Y). Body) is obtained.

  Next, the diaper continuous body 110 is fused at the side seal portion formation planned portion 110 </ b> C to form the side seal portion 4. FIG. 7 shows a suitable laser fusing device 120 used for forming the side seal portion 4. By using this device 120, the side seal part 4 can be successfully formed in the outer side of the fusion part 40 in the lateral direction Y in which the non-joint part is substantially absent and the side seal part 4 has a small thickness. Can do.

The method for forming the side seal portion 4 using the laser fusing device 120 shown in FIG. 7 is based on the edges between the side edges of the ventral side F of the exterior body 3 and the side edges of the back side R of the exterior body 3. A method of forming the side seal part 4 having a fused part 40 (see FIG. 3) fused in a state where the parts overlap each other;
At least a part of the sheets constituting the exterior body 3 includes a resin material,
A light passage portion through which laser light can pass through one surface of the sheet laminate in which both side edges of the ventral side F of the exterior body 3 and both side edges of the back side R of the exterior body 3 are overlapped. The sheet laminated body brought into contact with the supporting member having a pressure state is absorbed by the sheet constituting the sheet laminated body from the supporting member side through the light passing portion and generates heat. By irradiating the laser beam having the wavelength to be cut, the sheet laminated body is divided, and at the same time, the cut edges of the exterior body 3 in the pressurized state generated by the division are fused to form the fused portion. 40 is formed. Hereinafter, this method will be described with reference to FIG.

  As shown in FIG. 7, the laser-type bonding device 120 is arranged in a hollow cylindrical roll 123 having a cylindrical (annular) support member 121 that is rotationally driven in the direction of arrow A, and in a hollow portion of the support member 121. , An irradiation head 135 for irradiating the laser beam 130, an endless pressure belt 124 (pressing member) as pressure means, and a plurality of rolls 125a, 125b that rotate in a state where the pressure belt 124 is stretched. And a belt type pressure device 126 provided with 125c. The laser-type bonding apparatus 120 includes a tension adjusting mechanism (not shown) that can adjust the tension of the pressure belt 124 wound around the outer peripheral surface of the annular support member 121 (the peripheral surface portion of the cylindrical roll 123). By adjustment, the pressure applied to the diaper continuous body 110 (sheet laminated body) can be appropriately adjusted by the support member 121 and the pressure belt 124. The diaper continuous body 110 is a precursor for producing the diaper 1 of the present embodiment, and has a shape in which a plurality of diapers 1 are arranged along the lateral direction Y. In this diaper continuous body 110, the waist elastic members 51a and 51b are not joined to the exterior body 3 in the planned cutting portion 110C and the vicinity thereof, and are in a non-joined state.

  The support member 121 forms a peripheral surface portion (contact portion with the workpiece) of the cylindrical roll 123, and is sandwiched between a pair of annular frames 122 and 122 that form both left and right edge portions of the cylindrical roll 123. It is fixed. The support member 121 is composed of a single annular member having the same length as the circumferential length of the annular frame 122, for example, and has heat resistance such as a metal material such as iron, aluminum, stainless steel, copper, or ceramics. Made of material.

  The support member 121 has a light passage part through which laser light can pass. The support member 121 has a slit-shaped opening 127 that penetrates the support member 121 in the thickness direction as a light passage portion. The opening 127 has a rectangular shape in plan view, and its longitudinal direction coincides with the width direction of the support member 121 (direction parallel to the rotation axis of the cylindrical roll 123), so that the circumference of the cylindrical support member 121 is A plurality are formed at predetermined intervals in the direction. The support member 121 allows the laser light to pass through the opening 127, but does not allow the laser light to pass through (transmits) at portions other than the opening 127. As a method of forming the opening 127 in the support member 121, 1) In addition to a method of drilling the opening 127 in a predetermined portion of the support member 121 by etching, punching, laser processing, or the like, 2) As the support member 121, A method of using a plurality of curved rectangular members in place of one annular member, and arranging the plurality of members between a pair of frame bodies 122, 122 at a predetermined interval in the circumferential direction of the frame body 122 Is mentioned. In the method 2), the interval between two adjacent members is a slit-shaped opening 127.

  In the laser-type bonding apparatus 120, the light passing portion through which the laser light can pass is composed of a slit-shaped opening 127 that penetrates the support member 121 in the thickness direction, and thus overlaps with the opening 127 in the diaper continuous body 110. The part, that is, the part to be divided 110 </ b> C, is merely sandwiched between the support member 121 and the pressure belt 124 only by the pressure belt 124 contacting. Strictly speaking, therefore, the pressure that is generated by being sandwiched between the members 121 and 124 is not generated in the parting portion 110C. However, even if the part to be divided that overlaps the opening 127 itself is not sandwiched between the two members 121 and 124, the vicinity thereof, that is, the part that overlaps the vicinity of the opening 127 in the diaper continuous body 110 is both members 121 and 124. Therefore, the cutting edge portion generated by the division of the diaper continuum 110 by the laser light irradiation does not move. That is, the parting plan part of the diaper continuous body 110 is a part restrained by the pressurization force between the members 121 and 124, and the pressurizing force is a part that is practically affected.

  The belt type pressure device 126 includes an endless pressure belt 124 and three rolls 125a, 125b, and 125c that rotate in a state where the pressure belt 124 is bridged. The rolls 125a, 125b, and 125c may be drive rolls or driven rolls that rotate with the cylindrical roll 123. The pressure belt 124 rotationally drives any one or more of the rolls 125a, 125b, and 125c, and moves at the same speed as the cylindrical roll 123 (support member 121). The support member 121 and the pressure belt 124 are preferably maintained in a predetermined temperature range by air cooling, water cooling, or the like.

  As the pressure belt 124, a metal or resin belt having heat resistance capable of withstanding the heat generated during processing can be used, and it is made of a metal material such as iron, aluminum, stainless steel, or the like. In addition, as the pressure belt 124, a belt that does not transmit the laser beam irradiated to the diaper continuous body 110, which is a workpiece, is usually used. it can.

  As shown in FIG. 7, an irradiation head 135 that irradiates a laser beam 130 toward the support member 121 that forms the peripheral surface portion of the cylindrical roll 123 is provided in the hollow portion of the hollow cylindrical roll 123 (support member 121). ing. The irradiation head 135 is a galvano scanner that freely scans the laser beam 130, a mechanism for moving the laser beam 130 back and forth in a direction parallel to the rotation axis of the cylindrical roll 123, and the diaper continuum 110 on the support member 121. Are provided with a mechanism for moving the position (irradiation point) in the circumferential direction of the cylindrical roll 123, a mechanism for making the spot diameter of the laser light 130 constant on the peripheral surface of the cylindrical roll 123, and the like. With the laser irradiation mechanism having such a configuration, the irradiation point of the laser beam 130 is set in both directions of the circumferential direction of the cylindrical roll 123 and the direction parallel to the rotational axis of the cylindrical roll 123 perpendicular to the circumferential direction. It can be moved arbitrarily.

  As shown in FIG. 7, the diaper continuous body 110 includes a support member 121 that forms a peripheral surface portion of a cylindrical roll 123 that is rotationally driven in the direction of arrow A in a state where a predetermined tension is applied by a guide roll (not shown). After being introduced onto the outer surface and transported by a predetermined distance in the circumferential direction by the rotation of the cylindrical roll 123 so as to be wound around the support member 121, it is separated from the support member 121 by an unillustrated lead roll, nip roll or the like. In this way, the diaper continuum 110 is wound around the support member 121 forming the peripheral surface portion of the cylindrical roll 123 with a predetermined tension and conveyed so as to be in pressure contact with the pressure belt 124. Since the portion sandwiched between the support member 121 and the pressure belt 124 and the vicinity thereof are pressurized in the thickness direction before being divided by the laser light irradiation, the diaper continuous body 110 is made of a synthetic resin. When the nonwoven fabric is included, the diaper continuum 110 can be more efficiently compressed. As a result, when the diaper continuum 110 under compression is irradiated with laser light and divided, It becomes possible to fuse the cutting edges of a plurality of sheets constituting the divided portion more securely, and in the side seal portion 4 Further improvement in fusion strength of the destination unit is achieved.

  The rotation angle of the support member 121 (cylindrical roll 123) from when the diaper continuous body 110 is introduced onto the support member 121 to when the diaper continuous body 110 leaves the diaper continuous body 110 can be, for example, 90 degrees or more and 270 degrees or less. Is 120 degrees or more and 270 degrees or less. In addition, the range of the angle at which the diaper continuous body 110 is pressed against the support member 121 by the pressure belt 124 is 360 ° when the entire circumference of the cylindrical support member 121 (cylindrical roll 123) is pressed. In addition, it is preferably 90 degrees or more, more preferably 120 degrees or more, and preferably 270 degrees or less, more preferably 270 degrees or less. Specifically, it is preferably 90 degrees or more and 270 degrees or less, and more preferably 120 degrees or more and 270 degrees or less.

  In the method of forming the side seal portion 4, as shown in FIG. 7, while continuously conveying the diaper continuous body 110, one surface 110 a (see FIG. 8A) is formed on the peripheral surface portion of the cylindrical roll 123. The diaper continuum 110 in contact with the outer surface of the support member 121 and having a slit-shaped opening 127 through which the laser beam 130 can pass is pressed from the support member 121 side to the pressed diaper continuous body 110. The diaper continuum 110 is divided by irradiating the laser beam 130 through the, and at the same time, the cut edges of the plurality of sheets in the pressurized state generated by the division are fused together, The seal part 4 is formed.

  Specifically, as shown in FIG. 7, the other surface 110 b of the diaper continuum 110 that is in contact with the support member 121 (see FIG. 8A. One surface 110 a that is a contact surface with the support member 121 and Is pressed against the continuous surface of the diaper 110 in that state by irradiating the laser beam 130 through the slit-shaped opening 127 from the support member 121 side. The diaper 1 having the side seal portion 4 is continuously manufactured. In this way, the irradiation of the laser beam 130 is performed on the diaper continuum 110 that is in a pressurized state by being sandwiched between the support member 121 and the pressure belt 124. It is preferable from the viewpoint of reliably fusing the cut edge portions and improving the fusing strength of the side seal portion 4.

  FIGS. 8A to 8C are views for explaining a state in which the side seal portion 4 is formed at the same time as the diaper continuous body 110 is divided using the laser-type bonding apparatus 120. FIG. 1 schematically shows a portion 110C to be divided by the laser beam 130 of the diaper continuum 110 and its vicinity. 110 C of division | segmentation scheduled parts of the diaper continuous body 110 are the center of the conveyance direction A in the area | region where the absorptive main body 2 of the diaper continuous body 110 is not arrange | positioned. The parting plan part 110C is a four-layer structure part in which, for example, four sheets are stacked. As shown in FIG. 3A, the four-layer structure portion is composed of two sheets (outer layer sheet 31 and inner layer sheet 32) on the ventral side F and two sheets 31 and 32 on the back side R. These four sheets are laminated. The elastic filament 33 is interposed between the overlapping sheets 31 and 32. However, in FIGS. 6 (a) to 6 (c), the elastic member filament 33 is not shown for easy explanation. Yes.

  In the parting scheduled portion 110C of the diaper continuous body 110, the outer layer sheet 31 constituting one surface 110a (the contact surface with the support member 121) of the diaper continuous body 110 and a sheet other than the sheet constituting the one surface 110a (inner layer) The sheet 32) is a sheet in which either one or both absorb the laser beam 130 and generate heat. Further, the two overlapping sheets in the vicinity of the parting portion 110C and the vicinity thereof may be joined by an adhesive or the like before irradiation with the laser light 130, or may not be joined at all.

  As shown in FIG. 8B, the diaper continuous body 110 is arranged in the direction of arrow A so that one surface 110a is in contact with the support member 121 and the parting portion 110C is located on the slit-shaped opening 127. While being introduced onto the rotating support member 121 and being pressed against the other surface 110b, the pressure belt 124 is pressed in the thickness direction while being conveyed in the arrow A direction. During the conveyance, the laser beam 130 is irradiated from the support member 121 side through the opening 127 to the parting portion 110C in a pressurized state. As described above, the irradiation point of the laser beam 130 is configured to be arbitrarily movable in the circumferential direction of the cylindrical roll 123, and is set to move following the movement of the opening 127 along the circumferential direction. Therefore, the laser beam 130 is continuously irradiated for a certain period of time to the parting planned portion 110C located on the opening 127 during the transportation.

  When the laser beam 130 is irradiated to the parting planned portion 110C, the forming material (synthetic fiber, etc.) of the sheets 31 and 32 existing in the parting planned part 110C is vaporized by the heat generated by the direct irradiation of the laser light 130, The forming material which disappears from the region and is present in the vicinity of the portion 110C to be divided is indirectly heated by the laser beam 130 and melted. As a result, as shown in FIG. 8 (c), the part to be cut 110C is melted and one diaper 1 is separated from the diaper continuous body 110. At the same time, the diaper continuous body 110 is cut. The cut edges of the four sheets 31 and 32 in the diaper 1 generated by the division and the cut edges of the four sheets 31 and 32 in the separated diaper continuous body 110 are fused. . Each of these cut edges is in a pressurized state (compressed state) by being sandwiched between the support member 121 and the pressure belt 124 from before the formation (before the diaper continuous body 110 is divided by irradiation of the laser beam 130). ).

  According to the method for forming the side seal portion 4 using the apparatus shown in FIG. 7, the diaper continuous body 110 is divided by a single laser light irradiation, and the sheet is in two pressurized states generated by the division. In order to carry out the fusion of the cutting edges at the same time, the fusion and separation are the same with approximately half the laser output compared to the method of fusing the two fusion places with two laser irradiations. It can be carried out in a process, and the diaper 1 can be manufactured efficiently. Moreover, since fusion and parting can be performed in the same process, a non-joint part in which the cut edges of the sheet are not fused is not generated, so that the appearance of the diaper 1 is improved.

  The cut edges of the sheets 31 and 32 are heated and melted during the irradiation of the laser beam 130 and immediately after the end of the irradiation, but each one separated from the diaper continuous body 110 by the irradiation of the laser beam 130. The leaf diaper and the diaper continuum 110 are easily cooled by the contact of the support member 121 after the irradiation is completed, while being pressed by the support member 121 and the pressure belt 124. Then, it is quickly cooled and solidified by heat transfer to the pressure belt 124, and the material for forming the cutting edge including the adhesive is fused and integrated. By forming the fusion part 40 in this way, one of the pair of side seal parts 4 and 4 in one diaper 1 is formed. If necessary, the cutting edge portions of the sheets 31 and 32 may be forcibly cooled by using known cooling means such as a suction device or an exhaust device to promote the formation of the fused portion 40.

  When one portion 110C to be divided is divided in this way, the laser beam 130 is moved so that the irradiation point hits another opening 127 adjacent in the direction opposite to the conveyance direction A, and the other opening 127 is separated. 110C is irradiated to another parting planned portion 110C located above the part. Thereby, another part 110C to be divided is divided and fused in the same manner as described above, and the other side seal part 4 that forms a pair with the previously formed side seal part 4 is formed. Thereafter, the same operation is repeated to continuously manufacture the diaper 1 having the pair of side seal portions 4 and 4. In this method, the side seal part 4 of the diaper 1 is formed by a fusion method by irradiation with laser light, and is not formed by another fusion method.

  In the fused portion 40 of the side seal portion 4 formed in this way, the elastic member contracts by fusing the elastic members 51a and 51b due to the forming method, and the side seal portion 4 The elastic member comes off in the Y direction from the fused portion 40. As a result, a plurality of minute voids are formed in the fused portion 40. Therefore, the gap and the elastic member are located at the same position in the X direction. Due to the presence of this gap, the light transmission and reflection of the fused part 40 change according to the incident angle of light, and there is an advantage that the visibility of the side seal part 4 having a small thickness T1 and less noticeable is increased. Further, since the elastic members 51a and 51b do not exist at the position where the gap exists, there is an advantage that the side seal portion 4 is easily torn when the side seal portion 4 is torn and the diaper 1 is taken off. In contrast, if there is an elastic member in the side seal portion 4, when the side seal portion 4 is torn, the elastic member is stretched and the elastic member is not easily cut. May occur.

  Compared to the width W of the slit-shaped opening 127 irradiated with the laser light 130 (see FIG. 8B, the length of the opening 127 along the circumferential direction of the cylindrical roll 123), the diaper continuous body When the diameter φ of the spot of the laser beam 130 at 110 (the portion irradiated with the laser beam 130) is small (when φ / W is less than 1), it is formed by irradiation with the laser beam 130 as shown in FIG. The pair of side seal portions 4, 4 is a portion overlapping the opening 127 in the diaper continuous body 110 (a pair of opening edges along the direction orthogonal to the conveying direction A of the slit-shaped opening 127 in plan view) A portion sandwiched between the two). That is, in the diaper continuous body 110, even if it is a portion that is not sandwiched between the support member 121 and the pressure belt 124, the vicinity of the opening 127, that is, as described above, by the sandwiching between both the members 121 and 124. If it is a site where the pressure is substantially affected, the fused portion 40 can be formed.

In the diaper 1 obtained in this way, as shown in FIG. 3 described above, the thickness T1 of the side seal portion 4 is such that each of the ventral side portion F and the back side portion R of the exterior body 3 that constitutes this. The thickness is larger than the thickness T2 of the portion adjacent to the side seal portion 4. The thickness T2 of the ventral side F and the back side R of the outer package 3 is a load of 0.5 cN / cm ² at a substantially intermediate position between the side seal part 4 and the side edge of the absorbent main body 5. The measurement target part (side seal part) is sandwiched between flat plates, and three cross-sections separated in the longitudinal direction in one diaper are observed at a magnification of 50 to 200 times with a microscope (VHX-1000 manufactured by KEYENCE). In each cross section, the thickness of the part to be measured can be obtained, and the thickness can be obtained as an average value of the three thicknesses.

  As mentioned above, although this invention was demonstrated based on the preferable embodiment, this invention is not restrict | limited to the said embodiment. For example, in the above-described embodiment, as a preferable manufacturing method of the side seal portion S, the fusing by laser light using the apparatus shown in FIG. 7 has been described as an example. For example, a heat sealing method, an ultrasonic sealing method, a high frequency sealing method, an adhesive bonding method, or the like may be employed.

  Moreover, you may use what is shown in FIG. 10 as an exterior body. The exterior body 3 shown in the figure has an outer layer sheet 31 and an inner layer sheet 32, and a plurality of elastic members 80 extending along the lateral direction of the diaper 1 are disposed between the sheets 31, 32 in an expanded state. It is what. Each elastic member 80 is fixed to at least one of the outer layer sheet 31 and the inner layer sheet 32 only at both ends thereof. At the same time, each of the elastic members 80 is in an unfixed state in both the outer layer sheet 31 and the inner layer sheet 32 at a portion between both end portions. And the outer layer sheet | seat 31 and the inner layer sheet | seat 32 are intermittently joined by the junction part 63 between the two elastic members 80 adjacent along the longitudinal direction X of the diaper 1. As shown in FIG. It is preferable that the joining part 63 has comprised the joining part row | line | column 64 in series along the vertical direction X of the diaper 1, as shown in the figure. And it is preferable that this joining part row | line | column 64 is arrange | positioned in parallel in the horizontal direction Y of the diaper 1. FIG. By employing such an exterior body 3, it is possible to form a ridge having a good appearance.

  Moreover, although the diaper of the said embodiment had the exterior body 3 covering the back side part R through the crotch part C from the abdominal side part F, and the absorptive main body arrange | positioned on the inner surface, Instead, the present invention is applied to a pants-type disposable diaper in which an absorbent main body straddles between a ventral sheet member including a waist circumference elastic member and a back side sheet member similarly including a waist circumference elastic member. May be.

  Moreover, in the said embodiment, although elastic member non-arrangement area | region 9a, 9b was formed in both the abdominal side part F and the back side part R of the diaper 1 on both sides of the side seal part 4, it replaces with this and a diaper The elastic member non-arrangement region may be formed only on one ventral side portion F. Or you may form an elastic member non-arrangement field in both ventral side F and back side R.

  Moreover, in the said embodiment, although the elastic member non-arrangement area | region 9a, 9b was formed only in the upper area of the vertical direction X of the side seal part 4, it replaced with this and the elasticity joined by the adhesive agent is used. By changing the arrangement position of the members, the elastic member non-arrangement region may be formed only in the lower region in the longitudinal direction X of the side seal portion 4, or may be formed in both the upper region and the lower region. Or you may form only in a center area. Furthermore, the elastic member non-arrangement region may be formed over the entire region in the vertical direction X of the side seal portion 4.

This invention discloses the following underpants type disposable diaper regarding embodiment mentioned above further.
<1>
A pair of sides formed by joining the crotch, the abdominal side and the back side extending from the front and back of the crotch, both side edges of the abdomen, and both side edges of the back side A pants-type disposable diaper comprising a seal portion and having a longitudinal direction corresponding to the front-rear direction of the wearer and a lateral direction perpendicular thereto;
The side seal portion has a fusion portion that continuously extends along the longitudinal direction of the diaper, and the non-joint portion is substantially non-externally disposed laterally outward of the diaper from the fusion portion. Has become,
A plurality of elastic members are joined to the ventral portion and the dorsal side portion by an adhesive under an extended state,
The elastic member is colored in a color different from the background color of the abdominal side portion or the back side portion where the elastic member is disposed at least at the end portion located near the side seal portion and the vicinity thereof. And
At least a part of the elastic member has an end portion located near the side seal portion of the end portion that does not reach the position of the side seal portion. The elastic member non-arrangement region is formed between the side seal portion and the end portion of the elastic member.
A pants-type disposable diaper in which the adhesive for joining the elastic member is absent in the elastic member non-arrangement region.

<2>
The underpants type disposable diaper as described in <1> in which the said non-joining part of 1 mm or less exists.
<3>
The pants-type disposable diaper according to <1> or <2>, wherein the side seal part has a thickness of preferably 0.2 mm or more, more preferably 0.25 mm or more.
<4>
The pants-type disposable diaper according to any one of <1> to <3>, wherein the side seal part has a thickness of preferably 2 mm or less, more preferably 1.5 mm or less.
<5>
It further has an exterior body, and a waist elastic member disposed on the exterior body,
The color difference between the color of the waist elastic member and the ground color of the exterior body is represented by [a value of exterior body−a value of elastic member], and the value is preferably 10 or more, The pants-type disposable diaper according to any one of <1> to <4>, more preferably 15 or more.
<6>
And further comprising an exterior body and an abdominal waist elastic member disposed on the abdomen side of the exterior body,
The abdomen waist elastic member is colored in a color different from the ground color of the exterior body constituting the abdomen, at least at the end portion and in the vicinity thereof, preferably the entire region of the abdomen waist elastic member. <1> thru | or the pants type disposable diaper any one of <5>.

<7>
<1> to <6>, further comprising an exterior body, the exterior body including an outer layer sheet and an inner layer sheet, and the outer layer sheet and the inner layer sheet are configured such that constituent fibers themselves are elongated. The pants-type disposable diaper according to any one of the above.
<8>
The outer body further includes an outer layer sheet and an inner layer sheet, and the outer layer sheet and the inner layer sheet may be separated from each other at the intersection even if the constituent fibers themselves do not stretch. The three-dimensional structure formed by a plurality of fibers is structurally changed due to bonding of the fibers and the like, and the constituent fibers are broken, so that the outer layer sheet and the inner layer sheet as a whole can be stretched <1. > A pants-type disposable diaper according to any one of <7>.
<9>
The exterior body further includes an outer layer sheet and an inner layer sheet, and each of the outer layer sheet and the inner layer sheet is composed of two or more components of low melting point component and high melting point component. <1> thru | or the underpants type disposable diaper any one of <8>.
<10>
Each of the outer layer sheet and the inner layer sheet is a pants-type disposable diaper according to <9>, in which constituent fibers (non-elastic fibers) are joined at fiber intersections by thermal fusion of at least a low melting point component.
<11>
<1> thru | or <10> any one of <1> thru | or <10> from which the color of the said elastic member distribute | arranged to the said stomach part differs from the color of the said elastic member distribute | arranged to the said back | dorsal part. Pants-type disposable diaper.

<12>
The underpants type according to any one of <1> to <11>, wherein when the diaper is measured from the outside of the exterior body, the lightness of the elastic member non-arranged region is different from the lightness of the other region Disposable diapers.
<13>
When the diaper is measured from the outside of the exterior body, the ratio L2 / L1 between the lightness L1 of the elastic member non-arranged region and the lightness L2 of the other region is preferably 1.02 or more, more preferably 1. The pants-type disposable diaper according to <12>, which is 04 or more.
<14>
When the diaper is measured from the outside of the exterior body, the ratio L2 / L1 between the lightness L1 of the elastic member non-arranged region and the lightness L2 of the other region is preferably 1.3 or less, more preferably 1. The pants-type disposable diaper according to <12> or <13>, which is 25 or less.
<15>
The underpants-type disposable diaper according to any one of <1> to <14>, wherein a plurality of voids exist in the fusion part of the side seal part.
<16>
The pants-type disposable diaper according to <15>, wherein the gap and the elastic member are located at the same position in the longitudinal direction.
<17>
The pants-type disposable diaper according to any one of <1> to <16>, wherein the elastic member non-arrangement region is formed in at least one of an upper region and a lower region in the vertical direction of the side seal portion.

<18>
The elastic member non-arrangement region is the underpants type disposable diaper according to <17>, which is formed only in the upper region of the side seal portion in the vertical direction X.
<19>
The waist area of the ventral side and the back side is configured to include an elastic sheet having a configuration in which a thread-like elastic filament is bonded to one surface of an extensible fiber layer mainly composed of non-elastic fibers, The pants-type disposable diaper according to any one of <1> to <18>, wherein a part of the inelastic fiber is fused with the elastic filament and buried in the elastic filament.
<20>
The pants-type disposable diaper according to <19>, wherein the elastic filament is disposed between two sheets constituting the stretchable sheet, and no adhesive is present between the sheet and the elastic filament.
<21>
It further has an exterior body, and a waist elastic member disposed on the exterior body,
The waist elastic member colored in a color different from the background color of the belly side or the back side is visible from the appearance of the diaper, that is, through the exterior body sandwiching the waist elastic member. The pants-type disposable diaper according to any one of <1> to <20>.
<22>
<1> thru | or the manufacturing method of the pants type disposable diaper any one of <21>,
The exterior body continuous body on the abdomen side and the exterior body continuous body on the back side are overlapped to obtain an exterior body continuous laminate, and the formation site of the side seal portion in the exterior body continuous laminate is determined. The manufacturing method of a pants-type disposable diaper which has the process of fusing and forming this side seal part.
<23>
The side seal portion having a fused portion fused in a state where edges of both side edges of the abdomen side portion of the exterior body and both side edge portions of the back side portion of the exterior body overlap; Having a step of forming using a type fusing device,
At least some of the sheets constituting the exterior body include a resin material,
A light passage portion through which laser light can pass through one surface of the sheet laminate in which both side edge portions of the abdomen side portion of the exterior body and both side edge portions of the back side portion of the exterior body are overlapped. The sheet laminated body brought into contact with the supporting member having a pressure state is absorbed by the sheet constituting the sheet laminated body from the supporting member side through the light passing portion and generates heat. By irradiating a laser beam having a wavelength to be cut, the sheet laminated body is divided, and at the same time, the cut edges of the outer package in a pressurized state generated by the division are fused to form the fused portion. The manufacturing method of the underpants type disposable diaper as described in <22> to form.

<24>
<22> or <23> according to <22> or <23>, in which the sheet constituting the outer package is stretchable, such as heat treatment, stretching between rolls, biting and stretching by tooth gaps or gears, and tensile stretching by a tenter. A manufacturing method for disposable diapers.
<25>
The method for producing a pants-type disposable diaper according to any one of <22> to <24>, wherein the elastic filament is formed by stretching an elastic resin in a melted or softened state.
<26>
Any one of <22> to <25>, in which heat is not applied to the sheet constituting the outer package, and the elastic filament is fused to the sheet before the elastic filament obtained by melt spinning is solidified. The manufacturing method of the underpants type disposable diaper of description.
<27>
The method for producing a pants-type disposable diaper according to any one of <22> to <26>, wherein the sheet constituting the exterior body is preferably not stretchable in a state of the original fabric.
<28>
The exterior body continuum on the ventral side and the exterior body continuum on the back side are overlapped to obtain an exterior body continuous laminate, and the formation site of the side seal portion in the exterior body continuous laminate is melted. <1> thru | or <21> The underpants type disposable diaper which is manufactured by the manufacturing method of the underpants type disposable diaper which has the process of forming this side seal part.

<29>
The side seal portion having a fused portion fused in a state where edges of both side edges of the abdomen side portion of the exterior body and both side edge portions of the back side portion of the exterior body overlap; Manufactured by a method of manufacturing a pants-type disposable diaper having a step of forming using a type fusing device,
At least some of the sheets constituting the exterior body include a resin material,
A light passage portion through which laser light can pass through one surface of the sheet laminate in which both side edge portions of the abdomen side portion of the exterior body and both side edge portions of the back side portion of the exterior body are overlapped. The sheet laminated body brought into contact with the supporting member having a pressure state is absorbed by the sheet constituting the sheet laminated body from the supporting member side through the light passing portion and generates heat. By irradiating a laser beam having a wavelength to be cut, the sheet laminated body is divided, and at the same time, the cut edges of the outer package in a pressurized state generated by the division are fused to form the fused portion. The formed pants-type disposable diaper according to <28>.
<30>
<28> or <29> manufactured by performing heat treatment, stretching between rolls, biting by a tooth gap or gear, tensile stretching by a tenter, etc. in order to make the sheet constituting the exterior body extendable Pants-type disposable diapers as described.
<31>
The pants-type disposable diaper according to any one of <28> to <30>, wherein the elastic filament is formed by being stretched in a state where an elastic resin is melted or softened.
<32>
Heat is not applied to the sheet constituting the outer package, and the elastic filament obtained by melt spinning is manufactured by fusing the elastic filament to the sheet before solidifying <28>. Thru | or the pants type disposable diaper any one of <31>.

DESCRIPTION OF SYMBOLS 1 Pants type disposable diaper 2 Absorbent main body 3 Exterior body 10 Diaper continuous body (exterior body continuous laminated body)
30 elastic sheet 31 outer layer sheet 32 inner layer sheet 33 elastic filament 4 side seal part 40 fusion part 51a of side seal part abdominal waist elastic member 51b back waist elastic member 9a, 9b elastic member non-arrangement region F abdominal side part M Inseam R Back side

Claims (6)

A pair of sides formed by joining the crotch, the abdominal side and the back side extending from the front and back of the crotch, both side edges of the abdomen, and both side edges of the back side A pants-type disposable diaper comprising a seal portion and having a longitudinal direction corresponding to the front-rear direction of the wearer and a lateral direction perpendicular thereto;
The side seal portion has a fusion portion that continuously extends along the longitudinal direction of the diaper, and the non-joint portion is substantially non-externally disposed laterally outward of the diaper from the fusion portion. Has become,
A plurality of elastic members are joined to the ventral portion and the dorsal side portion by an adhesive under an extended state,
The elastic member is colored in a color different from the background color of the abdominal side portion or the back side portion where the elastic member is disposed at least at the end portion located near the side seal portion and the vicinity thereof. And
At least a part of the elastic member has an end portion located near the side seal portion of the end portion that does not reach the position of the side seal portion. The elastic member non-arrangement region is formed between the side seal portion and the end portion of the elastic member.
A pants-type disposable diaper in which the adhesive for joining the elastic member is absent in the elastic member non-arrangement region.   The underpants-type disposable diaper according to claim 1, wherein the color of the elastic member disposed on the abdomen and the color of the elastic member disposed on the back side are different.   The underpants-type disposable diaper according to claim 1 or 2, wherein the lightness of the elastic member non-arrangement region is different from the lightness of the other region.   The underpants type disposable diaper as described in any one of Claim 1 thru | or 3 with which several space | gap exists in the said melt | fusion part of the said side seal part.   The underpants-type disposable diaper according to any one of claims 1 to 4, wherein the elastic member non-arrangement region is formed in at least one of an upper region and a lower region in the vertical direction of the side seal portion.   The waist area of the ventral side and the back side is configured to include an elastic sheet having a configuration in which a thread-like elastic filament is bonded to one surface of an extensible fiber layer mainly composed of non-elastic fibers, The pants-type disposable diaper according to any one of claims 1 to 5, wherein a part of the non-elastic fiber is fused with the elastic filament and buried in the elastic filament.