JP2017080028A - Absorbent article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an absorbent article having a cloth-like back sheet, capable of suppressing humidity generated from an absorber from moving to a direct clothing side while making a back sheet texture constant, and excellently retaining adhesive strength between a polyolefin film and a nonwoven fabric.SOLUTION: An absorbent article includes a top sheet, a back sheet, an absorber, and a flap part. The absorbent article is such that: the back sheet is a composite sheet where an air permeable polyolefin film and a nonwoven fabric are intermittently adhered by a hot melt based adhesive; an application pattern of the hot melt based adhesive in the back sheet comprises a straight line and a sawtooth-like wavy line in a portion where the back sheet contacts the absorber, and comprises a plurality of circles overlapped on each other in the flap part; and an application area and an application quantity of the hot melt based adhesive are each in a prescribed range in the portion where the back sheet contacts the absorber, and the flap part.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an absorbent article using a cross-like back sheet having good air permeability.

  Absorbent articles such as tape-type diapers, urine pads, light incontinence pads, and sanitary products are generally disposed between a liquid-permeable top sheet and a liquid-impermeable back sheet. And an absorber. This liquid-impermeable back sheet is required not to leak body fluid absorbed by the absorbent body to the outside, and vapor and moisture generated by urination and the like during wearing of the absorbent article to the outside of the absorbent article. In order to dissipate, it is required to have a certain degree of moisture permeability. Furthermore, since the back sheet is disposed on the contact side with clothing or the outer, it is also required to have excellent texture. In order to improve this texture, a so-called cross-like back sheet is used in which a nonwoven fabric and a synthetic resin film such as a polyolefin-based film are bonded together so that the nonwoven fabric is the outermost side. The cross-like back sheet has a cross-like touch, and has a feature that it has a frictional resistance compared to the synthetic resin film alone when it is brought into contact with clothing or an outer layer, and the absorbent article is not easily displaced. Yes.

  When laminating the nonwoven fabric and the synthetic resin film that make up the cross-like back sheet, a hot-melt adhesive is usually used. Also, as a coating method, a molten adhesive is applied in a non-contact manner from a nozzle in the form of a thread. A curtain coating method, a spiral method, a contact method, a slot method for applying a surface, and a spray method for applying in a mist form are generally used. However, regardless of which application method is used, the back sheet bonded with a non-woven fabric and a synthetic resin film using a hot melt adhesive has the disadvantage that the flexibility is lowered and the texture becomes hard. Therefore, there has been a demand for an absorbent article that improves the texture and does not inhibit moisture permeability.

  As an absorbent article which copes with such a problem, for example, Patent Document 1 discloses a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent body interposed between the top sheet and the back sheet. An absorptive article in which the back sheet is formed of a sheet material in which a microporous resin film and a nonwoven fabric are laminated is disclosed.

  Patent Document 2 discloses a moisture-permeable sheet that is used as a back sheet for absorbent articles and the like, and is formed by laminating a breathable film and a nonwoven fabric made of a resin mainly composed of propylene / ethylene random copolymer. It is disclosed.

  Patent Document 3 discloses a composite sheet used as a back sheet of an absorbent article and the like, in which a liquid-impermeable sheet and a nonwoven fabric are bonded via an adhesive. An invention is disclosed in which the diameter, basis weight, melt viscosity, fiber diameter, coating amount, etc. of a fibrous adhesive used as an adhesive are adjusted.

  In Patent Document 4, a porous moisture-permeable polyolefin-based film having a cylindrical foot portion at the periphery of an aperture and a polyolefin-based melt blown nonwoven fabric are overlapped so that the cylindrical foot portion of the porous moisture-permeable polyolefin-based film is disposed inside. A back sheet for an absorbent article that has been laminated and integrated is disclosed.

JP 09-173382 A JP 09-295366 A JP-A-10-109371 Japanese Patent Laid-Open No. 11-348163

  However, in the absorbent article having improved absorption performance of the absorbent body, and in the absorbent article having the cross-like back sheet, no consideration is given to the breathability of the absorbent body portion. It is not possible to respond sufficiently to the increase in moisture permeation due to improved absorption of water, and vapor and moisture from urination etc. reach the clothing through the cross-like back sheet, and the wearer feels that the clothing is wet was there. In addition, when adjusting the application amount and application pattern of the hot melt adhesive in consideration of air permeability, although the air permeability and touch of the back sheet are improved, due to insufficient adhesive strength between the polyolefin film and the nonwoven fabric, There was a possibility that the nonwoven fabric would be peeled off from the polyolefin film.

  Therefore, in view of the above problems, the present invention is directed to the absorbent article having a cross-like back sheet, in which moisture generated from the absorbent is directly transferred to the garment side while the back sheet feel is kept constant. An object of the present invention is to provide an absorbent article that can be suppressed and can maintain the adhesive strength between the polyolefin-based film and the nonwoven fabric as good.

  The inventor of the present invention has conducted extensive research in view of the above problems. As a result, in the absorbent article having a breathable polyolefin-based film and a backsheet in which a nonwoven fabric is laminated on the clothing-side contact surface of the polyolefin-based film, the backsheet includes a portion where the backsheet is in contact with the absorber and a flap portion. According to the absorbent article in which the hot melt adhesive is separately applied and the application pattern, the application area, and the application amount are separately adjusted, the above problems can be solved and the present invention has been completed. It was. Specifically, the present invention provides the following.

(1) A liquid-permeable top sheet constituting the body-side contact surface, a liquid-impermeable back sheet constituting the clothing-side contact surface, and an absorber disposed between the top sheet and the back sheet , A sheet constituting the body-side contact surface, and an absorbent article having a flap portion to which the back sheet is directly joined, the back sheet comprising a breathable polyolefin film and a polyolefin film garment A composite sheet having a nonwoven fabric laminated on a side contact surface, wherein the polyolefin film and the nonwoven fabric are intermittently adhered with a hot melt adhesive, and a coating pattern of the hot melt adhesive on the back sheet In the part where the back sheet is in contact with the absorber, a straight line and a sawtooth wave line alternately in parallel therewith In addition, the flap portion is composed of a plurality of overlapping circles, and the application area of the hot melt adhesive is equal to the planar area of the absorber at the portion where the back sheet is in contact with the absorber. 4% or more and 15% or less, and in the flap part, it is 0.5% or more and 50% or less of the area of the flap part, and the application amount of the hot melt adhesive is absorbed by the back sheet. The absorbent article is 5 g / m ² or more and 30 g / m ² or less at the portion in contact with the body and 10 g / m ² or more and 50 g / m ² or less at the flap portion.

  (2) A second aspect of the present invention is the absorbent article according to (1), wherein the application pattern of the hot-melt adhesive on the backsheet at a portion where the backsheet is in contact with the absorber. In addition, two straight lines adjacent to one sawtooth wave line are separated from 6 mm to 30 mm, the amplitude of the sawtooth wave line is 2.5 mm to 10 mm, and the wavelength is 5 mm to 25 mm, The thickness of the straight and sawtooth wavy lines is 0.2 mm or more and 1.5 mm or less.

  (3) A third aspect of the present invention is the absorbent article according to (1) or (2), wherein in the application pattern of the hot melt adhesive in the back sheet in the flap portion, The diameter of the plurality of overlapping circles is 5 mm or more and 30 mm or less, the adjacent circles overlap 10% or more and 40% or less of the diameter, and the circumferential thickness of the plurality of overlapping circles is 0.2 mm or more and 1 It is characterized by being 5 mm or less.

  (4) A fourth aspect of the present invention is the absorbent article according to any one of (1) to (3), wherein the backsheet and the above are used in the adhesive strength between the polyolefin film and the non-woven fabric. 180 ° peel strength is 0.9 / 50 mm or more and 2.2 N / 50 mm or less at the portion where the absorber contacts, and 180 ° peel strength is 1.0 N / 50 mm or more and 1.5 N / 50 mm or less at the flap portion. It is characterized by.

  (5) A fifth aspect of the present invention is the absorbent article according to any one of (1) to (4), wherein the nonwoven fabric is a spunbond nonwoven fabric, a thermal bond nonwoven fabric, and a spunbond nonwoven fabric / meltblown. It is one of composite nonwoven fabrics of nonwoven fabric / spunbond nonwoven fabric.

  According to the present invention, the application pattern of the hot melt adhesive on the back sheet is composed of straight lines and sawtooth wavy lines alternately in parallel with the back sheet in contact with the absorber. In addition, the air flow rate can be controlled while sufficiently ensuring the air permeability of the back sheet in contact with the absorbent body, so that moisture and vapor generated from the absorbent body are transferred to the clothing side through the cross-like back sheet. Can be prevented. In addition to the hot melt adhesive application pattern, the hot melt adhesive application area and amount were also adjusted, so that the cross-like back sheet feels good and the polyolefin in the cross-like back sheet The adhesive strength between the base film and the nonwoven fabric can be maintained well.

It is the expanded view seen from the back sheet side of the absorbent article which concerns on this embodiment. It is the expanded view seen from the top sheet side of the absorbent article which concerns on this embodiment. (A) It is drawing which shows the application pattern of the back sheet of the site | part which contact | connects an absorber, and (b) the application pattern of the back sheet of a flap part.

  Hereinafter, a mode for carrying out the present invention (hereinafter referred to as “embodiment”) will be described in detail with reference to FIGS. 1 to 3. In the description of the embodiment, the same reference numerals are given to the same elements throughout. In the description of the present specification, “when the absorbent article is worn” means at least one of the absorbent article when worn and after wearing. Moreover, the longitudinal direction of the absorbent article is a direction extending in front of and behind the wearer when the absorbent article is worn, and is a direction indicated by a symbol Y in the figure. On the contrary, the transversal direction of the absorbent article is a direction transverse or orthogonal to the longitudinal direction, and is a direction indicated by a symbol X in the figure. Furthermore, the body-side contact surface is a surface arranged on the skin side of the wearer during wearing, out of the front and back surfaces of each member such as an absorbent body, and the clothing-side contact surface is the back surface of each member such as a back sheet. Of the front and back surfaces, the surface is directed to the side opposite to the wearer's skin when worn. The body fluid refers to a fluid discharged from the body such as urine, sweat, blood, and water in loose stool. Further, the absorbent article may be a tape-type disposable diaper, a pants-type disposable diaper, a urine-absorbing pad, a light incontinence pad, a sanitary product, etc., regardless of whether it is for infants or adults.

<Absorbent article>
FIG. 1 is a development view of the absorbent article 1 according to the present embodiment as viewed from the back sheet 20 side (upper surface side), and FIG. 2 illustrates the absorbent article 1 according to the present embodiment on the top sheet 10 side (upper surface). It is the development view seen from the side. As shown in FIG.1 and FIG.2, the absorbent article 1 comprised the liquid-permeable topsheet 10 which comprises a body side contact surface, and the clothing side contact surface, and was arrange | positioned facing the topsheet 10. FIG. A liquid-impermeable back sheet 20 and an absorber 30 disposed between the top sheet 10 and the back sheet 20 are provided. Thereby, the absorber 30 has a structure sandwiched between the top sheet 10 and the back sheet 20. Furthermore, the absorbent article 1 according to the present embodiment includes a flap portion 21 in which a sheet (for example, the top sheet 10) constituting the body-side contact surface and the back sheet 20 are directly joined without using the absorber 30. Have. That is, the flap portion 21 refers to a portion located around the absorbent body 30 where the absorbent body 30 is not present when the absorbent article 1 is viewed in plan. The absorbent article 1 has the above-described configuration, and further includes various components employed in the conventionally known absorbent article 1 except that the back sheet 20 described below is used as the back sheet 20. It may be.

[Back sheet]
The back sheet 20 used for the absorbent article 1 of the present invention has a breathable polyolefin film and a nonwoven fabric laminated on the clothing side surface of the polyolefin film, and the polyolefin film and the nonwoven fabric are hot melts. It is a composite sheet bonded intermittently with a system adhesive.

(Breathable polyolefin film)
The breathable polyolefin film is not particularly limited as long as it has waterproofness and moisture permeability. For example, a polyolefin resin and an inorganic filler such as calcium carbonate are melt-kneaded to form a film, Examples thereof include a porous film obtained by uniaxially or biaxially stretching this film, and a film obtained by embossing a polyolefin film. Examples of the polyolefin resin include polyethylene, polypropylene, and polybutene, and these can be used alone or in combination. Among the films using these polyolefin resins, the breathable polyolefin film is preferably a breathable polyethylene film from the viewpoint of water resistance and breathability.

The thickness of the breathable polyolefin film is preferably 15 μm or more and 40 μm or less, and more preferably 20 μm or more and 30 μm or less. The basis weight of the breathable polyolefin film is preferably 10 g / m ² or more and 30 g / m ² or less.

(Nonwoven fabric)
The material, production method, etc. of the nonwoven fabric used for the backsheet 20 are not particularly limited, and any nonwoven fabric can be used. For example, the nonwoven fabric produced from synthetic fibers such as polypropylene, polyethylene, polyester, etc. It is preferable that the production method is any one of a spunbond nonwoven fabric, a thermal bond nonwoven fabric, and a composite nonwoven fabric of spunbond nonwoven fabric / melt blown nonwoven fabric / spunbond nonwoven fabric. The basis weight of the nonwoven fabric is preferably 10 g / m ² or more and 30 g / m ² or less from the viewpoint of texture and strength, and the thickness of the nonwoven fabric is 30 μm or more and 1000 μm or less from the viewpoint of tactile sensation and air permeability. Preferably there is. Here, the thickness of the nonwoven fabric is measured using a thickness gauge (a dial thickness gauge “PEACOCK” manufactured by Ozaki Seisakusho). The measurement conditions were 35 gf / cm ² (measurement load 250 gf, probe diameter 30 mm), and 10 non-woven fabrics were placed between the probe and the measurement table, and the probe was dropped at a speed of 1 mm or less per second. The time gauge is read, and this is interrupted at 10 to calculate the thickness per sheet.

(Hot melt adhesive)
The back sheet 20 of the absorbent article 1 according to the present embodiment has the above-described breathable polyolefin film and nonwoven fabric bonded intermittently with a hot melt adhesive to form a composite sheet. Here, the hot melt adhesive used for forming the composite sheet is not particularly limited, and for example, a styrene / butadiene / styrene copolymer having a melting point of 100 ° C. or higher and 180 ° C. or lower. And a synthetic rubber-based hot-melt adhesive made of styrene / isoprene / styrene-based copolymer or an olefin-based hot-melt adhesive made of ethylene-vinyl acetate copolymer. As the hot melt adhesive, only one of these various hot melt adhesives may be used, or a plurality of hot melt adhesives may be blended.

(Application pattern of hot melt adhesive, application area, application amount)
In the present invention, the application pattern of the hot melt adhesive on the backsheet 20 needs to be different patterns for the portion where the backsheet 20 is in contact with the absorber 30 and the flap portion 21 where the absorber 30 is not present. . Thus, while making the breath sheet of the absorber 30 part favorable by making it into a separate pattern with the part which back sheet 20 touches absorber 30, and flap part 21 where absorber 30 does not exist, The adhesion between the polyolefin-based sheet and the nonwoven fabric in the entire back sheet 20 can be maintained satisfactorily.

  Specifically, in the portion where the back sheet 20 is in contact with the absorber 30, as shown in FIG. 3A, the coating pattern is composed of straight lines 25 and sawtooth-like wavy lines 24 alternately in parallel therewith. In the case of such an application pattern, the air permeability of the absorber 30 is maintained well, while the hot melt adhesive is uniformly distributed by the alternate combination of the straight line 25 and the sawtooth wavy line 24. Therefore, the adhesive strength between the polyolefin film and the nonwoven fabric is not significantly reduced while suppressing the amount of hot melt adhesive applied. In particular, the sawtooth coating pattern exhibits sufficient tensile strength even in the case of oblique pulling, and the use of hot-melt adhesives due to the fact that there are few curved parts compared to omega-like coating patterns. The amount can be reduced, and the air permeability of the back sheet 20 can be improved.

In this case, the application area of the hot melt adhesive at the portion where the back sheet 20 is in contact with the absorber 30 is 4% or more and 15% or less of the planar area of the absorber 30, and this application area is 7% or more. It is preferably 12% or less. Moreover, the application amount of the hot melt adhesive in the part is 5 g / m ² or more and 30 g / m ² or less, and the application amount is preferably 10 g / m ² or more and 15 g / m ² or less. By making the application area and the application amount of the hot-melt adhesive within the above range, the air permeability of the back sheet 20 at the absorber 30 portion is made good, and the texture of the back sheet 20 is kept good. On the other hand, the balance between the adhesive strength of the hot melt adhesive and the prevention of curing by application can be improved.

  Here, the saw-tooth wave line 24 and the straight line 25 appear alternately with each other at the portion where the back sheet 20 is in contact with the absorber 30, but as shown in FIG. The two straight lines 25 adjacent to 24 are preferably separated by 6 mm or more and 30 mm or less, the amplitude of the sawtooth wave line 24 is 2.5 mm or more and 10 mm or less, and the wavelength of the sawtooth wave line 24 is 5 mm or more and 25 mm or less. It is preferable that It is preferable that the sawtooth wave line 24 and the straight line 25 are separated from each other by 0.5 mm or more and 5 mm or less in the closest part, and the thickness of the sawtooth wave line 24 and the straight line 25 is 0.2 mm or more and 1. It is preferable that it is 5 mm or less. In the present invention, it is preferable that the size of the absorber center portion is set to a finer size and the size of the absorber edge portion is set to a coarser size within the above preferable size range.

Further, the flap portion 21 has a coating pattern composed of a plurality of continuous circles 26 that overlap each other. When such a coating pattern is used, the hot melt adhesive is evenly distributed on the backsheet 20, but the contact area between the breathable polyolefin film and the nonwoven fabric is increased. The adhesive strength between the polyolefin-based film and the nonwoven fabric is improved, including the back sheet end portion and the like that require stronger adhesive strength between the two. In this case, the application area of the hot melt adhesive in the flap part 21 is 0.5% or more and 50% or less with respect to the area of the flap part 21, and this application area is 5% or more and 15% or less. It is preferable that Moreover, the application amount of the hot melt adhesive in the part is 10 g / m ² or more and 50 g / m ² or less, and the application amount is preferably 10 g / m ² or more and 20 g / m ² or less. By making the application area and application amount of the hot-melt adhesive within the above range, the adhesive strength of the hot-melt adhesive and prevention of curing by application can be maintained while maintaining the texture of the back sheet. The balance can be made good.

  Here, in the flap portion 21, as shown in FIG. 3B, the diameter of the plurality of circles 26 overlapping each other is preferably 5 mm or more and 30 mm or less, and the adjacent circles 26 are 10% or more and 40% or more of the diameter. % Or less is preferable. Moreover, it is preferable that the thickness of the circumference | surroundings of the some circle 26 which mutually overlaps is 0.2 mm or more and 1.5 mm or less.

In addition, the application quantity of a hot-melt-type adhesive agent can be measured with the following method, for example. First, ten non-woven fabrics cut into 10 cm × 10 cm squares are collected, and the weight before the hot melt adhesive is applied is measured. After applying the hot melt adhesive with a transfer roll, similarly, 10 pieces cut into a 10 cm × 10 cm square are collected, and the weight after the hot melt adhesive is applied is measured. The difference in weight before and after application is determined. The above is repeatedly measured 5 times, and the average value is defined as the application amount (g / m ² ) of the hot melt adhesive. Moreover, as a measuring method of the application area of an application pattern, it can calculate by calculating | requiring the area of the whole printing plate corresponding to a nonwoven fabric, and a convex part top area, for example.

(Method of applying hot melt adhesive)
The application method of the hot melt adhesive is not particularly limited as long as it is an application method that can apply the hot melt adhesive in a predetermined pattern, and a known method can be used. For example, when a roll coater is used as a coating device, a relief plate having a predetermined coating pattern is formed on the surface of a transfer roll, and a hot melt adhesive is transferred and applied to the nonwoven fabric. In this case, the application pattern can be changed by exchanging the transfer roll.

(Adhesive strength between polyolefin film and non-woven fabric)
In the adhesive strength between the polyolefin film and the nonwoven fabric, the 180 ° peel strength is 0.9 / 50 mm or more and 2.2 N / 50 mm or less at the portion where the back sheet and the absorber are in contact, and the flap portion is 180 ° peel strength. Is preferably 1.0 N / 50 mm or more and 1.5 N / 50 mm or less, and more preferably 1.2 N / 50 mm or more and 1.6 N / 50 mm or less. In addition, this adhesive strength is a 180 degree peel strength about 75 mm in length which is a half of the back sheet cut into 50 mm in width and 150 mm in length using a Tensilon tensile tester under conditions of a test speed of 500 mm / min. Is obtained 10 times and the average value is calculated.

(Backsheet production method)
As a method for producing a back sheet 20 by bonding a nonwoven fabric and a breathable polyolefin-based film with a hot-melt adhesive, for example, a hot-melt adhesive is used with a transfer roll in which a relief plate is formed so as to have a predetermined coating pattern. Can be produced by transferring and coating a nonwoven fabric on a nonwoven fabric, setting a breathable polyolefin film thereon, and then heating and pressurizing a laminate of both for a predetermined time. At this time, the non-woven fabric is stretched in the width direction or the length direction in the range of 2% or more and 10% or less, and then bonded to the breathable polyolefin film, so that the shape of the non-woven fabric is restored to its original shape by tension. As a result, a gap that contributes to improvement in air permeability is formed between the air permeable polyolefin film and the nonwoven fabric.

[Top sheet]
The top sheet 10 may be made of a base material having liquid permeability that allows body fluid to move to the absorbent body 30. For example, a nonwoven fabric such as a thermal bond nonwoven fabric or a composite nonwoven fabric in which a thermal bond nonwoven fabric / spun bond nonwoven fabric is laminated. It is formed from a material such as an opening film such as an opening polyethylene film, a foam film such as polyethylene foam or urethane foam, or a composite sheet obtained by laminating these films. Moreover, in order to improve the liquid permeability, the top sheet 10 is preferably subjected to embossing or perforation on the surface, and the embossing or perforation can be performed by a conventionally known method. Furthermore, in order to reduce irritation to the skin of the top sheet 10, it is also preferable that the top sheet 10 contains a lotion, an antioxidant, an anti-inflammatory component, a pH adjuster, an antibacterial agent, a moisturizing agent and the like. The basis weight of the top sheet 10 is preferably 14 g / m ² or more and 40 g / m ² or less from the viewpoint of strength and workability. The shape of the top sheet 10 is not particularly limited, and may be any shape that covers the absorbent body 30 in order to guide the body fluid to the absorbent body 30 so as not to leak.

[Absorber]
The absorbent body 30 absorbs and retains body fluids, and contains, for example, fluff pulp and a super absorbent polymer (SAP). The base material of the absorbent body 30 is not particularly limited as long as it is generally used for absorbent articles such as sanitary napkins, diapers, and urine absorbing pads. For example, fluff pulp, cotton, rayon, acetate, tissue, absorption It is formed from materials such as paper and hydrophilic nonwoven fabric. Among these, it is preferable to use fluff pulp from the viewpoint of absorbability. Examples of such fluff pulp include wood pulp, synthetic fiber, polymer fiber, non-wood pulp and the like that have been fibrillated into cotton. The basis weight of the base material of the absorbent body 30 is preferably 100 g / m ² or more and 800 g / m ² or less in order to improve the absorption performance and the touch.

The SAP of the absorber 30 is not particularly limited as long as it absorbs body fluids (urine, sweat, blood, etc.) and can prevent backflow. For example, sodium polyacrylate, polyaspartic acid Examples include those formed from materials such as salt systems, (starch-acrylic acid) graft copolymers, (acrylic acid-vinyl alcohol) copolymers, (isobutylene-maleic anhydride) copolymers and saponified products thereof. it can. Among these, it is preferable to use a sodium polyacrylate system from the viewpoint of the amount of absorption per weight. The basis weight of the SAP of the absorbent body 30 is preferably 50 g / m ² or more and 500 g / m ² or less from the viewpoint of improving the absorption performance and the touch.

  Absorbent body 30 preferably contains a base material and SAP, and the structure is preferably formed by mixing SAP particles in the base material, or an SAP sheet in which SAP particles are fixed between the base materials. . Moreover, it is preferable to wrap the absorber 30 in a carrier sheet from the viewpoint of preventing leakage of SAP particles and stabilizing the shape of the absorber 30. As a base material of a carrier sheet, what is necessary is just to have hydrophilicity, and hydrophilic nonwoven fabrics, such as tissue, an absorbent paper, an airlaid nonwoven fabric, can be mentioned. When the absorber 30 includes a plurality of carrier sheets, the base material of the carrier sheet may be the same or different.

  The shape of the absorber 30 is not particularly limited, and examples thereof include a rectangular shape, an hourglass shape, and an I-shape. The absorber 30 may be used by stacking two or more layers.

[Other configurations of absorbent articles]
If the tape type disposable diaper which is a kind of the absorbent article 1 is described as an example with respect to the other configuration of the absorbent article 1 of the present invention, the absorbent article 1 is worn by the wearer as shown in FIG. A back body 2A disposed on the back side, a front body 2C disposed on the abdomen side, and a crotch 2B disposed between the back body 2A and the front body 2C. Fastening tapes 40 are provided in the left and right side edge regions of the back body 2A of the back sheet 20, and fastening regions 27 for locking the fastening tape 40 are formed in the front body 2C. The tape-type disposable diaper is worn by fastening the fastening tape 40 to the fastening region 27.

  As shown in FIG. 2, the absorbent article 1 can include leg gathers 70 and waist gathers 80 each having a gathering elastic member in order to improve the fit of the user. Moreover, in order to prevent the side leakage of the bodily fluid excreted by the user, the elastic member 50b for three-dimensional gathers is provided from the back body 2A through the crotch 2B to the front body 2C along the longitudinal direction of the absorbent article 1. A pair of three-dimensional gathers 50 may be provided.

  There is no restriction | limiting in particular as a manufacturing method of the absorbent article 1, A conventionally well-known method is employable. For example, after sandwiching the absorber 30 between the top sheet 10 and the back sheet 20 and further disposing the fastening tape 40, the fastening region 27, the three-dimensional gather 50, etc., the top sheet 10 and the back sheet 20 Can be manufactured by using a hot melt adhesive, heat seal, ultrasonic seal, high frequency seal or the like over a part or the entire circumference. Then, the fastening tape 40 may be bent and the absorbent article 1 may be folded in three along the longitudinal direction to fill the package.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated concretely, this invention is not limited by these Examples.

<Example 1>
(Preparation of back sheet)
The composite nonwoven fabric of spunbond nonwoven fabric / melt blown nonwoven fabric / spunbond nonwoven fabric (basis weight: 20 g / m ² ) has a pattern in which the portion in contact with the absorber is composed of straight and sawtooth wavy lines alternately in parallel with this, Styrene so that the application amount is 5 g / m ² at the part in contact with the absorber and the flap part is 10 g / m ² by the transfer roll in which the flap part is formed with a relief printing part having a pattern consisting of a plurality of overlapping circles. A hot melt adhesive of / butadiene / styrene copolymer was transferred and applied, and a breathable polyethylene film (basis weight: 15 g / m ² ) was set thereon. A nonwoven fabric and a breathable polyethylene film were integrated to prepare a back sheet. In addition, the ratio of the application area of the hot-melt adhesive was 4.8% at the portion in contact with the absorber and 0.5% at the flap portion.

(Production of absorbent articles)
A urine collecting pad having a length of 48 cm and a width of 19 cm was produced using the obtained back sheet. As the top sheet, an air-through non-woven fabric (basis weight 20 g / m ² ) is used, and as the absorber, a laminate of 27 g of fluff pulp and SAP 12 g is prepared and cut into a length of 42 cm and a width of 15 cm. Using.

<Example 2, Comparative Examples 1-3>
Except for changing the coating pattern, the ratio of the coating area, the coating amount, the dimensions of the structural unit, etc., as shown in Table 1, when laminating the nonwoven fabric and the breathable polyethylene film, the same as in Example 1 was performed. A urine collection pad was prepared.

<Humidity change measurement test>
The urine collecting pad having a length of 48 cm and a width of 19 cm obtained in Examples and Comparative Examples was placed on the acrylic plate so that the back sheet was in contact with the acrylic plate, and the amount of change in humidity was measured in an environment of 50% humidity. Tested. First, 300 ml of 0.9% physiological saline heated to 36 ± 2 ° C. was placed on the top sheet and left for 10 minutes. Thereafter, the front and back of the urine collecting pad were reversed and placed on an acrylic plate, and a vinyl chloride tube having an inner diameter of 50 mm and a height of 50 mm was placed in the center of the back sheet at the site in contact with the absorber. A hygrometer was placed on the inner diameter portion of the vinyl chloride tube, and the humidity after 1 minute was recorded.

<Comprehensive judgment>
In order to examine the effect of improving the texture, a monitor test with 20 monitors was also conducted, and a comprehensive evaluation was made based on the following criteria.
○: Both the adhesive strength and the amount of change in humidity were high, and 15 or more of 20 people judged that the texture was good.
Δ: Adhesive strength is high, but moisture permeability is low, and less than 10 out of 20 judges that the texture is good.
X: Adhesive strength is low but moisture permeability is high, and less than 5 out of 20 judges that the texture is good.

  In Example 1, although the application area and the application amount of the hot melt adhesive are small and the thickness of the line of the application pattern is thin, the minimum adhesive strength is maintained and the humidity change of the absorber portion is also good. It was. In Example 2, although the application area and the application amount of the hot-melt adhesive were large, the thickness of the line of the application pattern was thick, the humidity change of the absorber portion was good, and the adhesive strength was also good. In Comparative Example 1, since the application area and the application amount of the hot melt adhesive were large and the thickness of the line of the application pattern was also thick, even when the adhesive strength was good, the humidity change of the absorber portion was low. . In Comparative Example 2, the application area and the application amount of the hot melt adhesive were small, and the thickness of the line of the application pattern was thin, so that the adhesive strength was low. In Comparative Example 3, since the adhesive was applied by conventional slot coat coating, the adhesive strength was sufficient, but the moisture permeability did not satisfy the criteria of the present invention.

DESCRIPTION OF SYMBOLS 1 Absorbent article 10 Top sheet 20 Back sheet 21 Flap part 24 Sawtooth wave line 25 Straight line 26 yen 27 Fastening area 30 Absorber 40 Fastening tape 50 Three-dimensional gather 50b Three-dimensional gather elastic member 70 Leg gather 80 West gather

Claims (5)

A liquid-permeable top sheet constituting the body-side contact surface, a liquid-impermeable back sheet constituting the clothing-side contact surface, and an absorber disposed between the top sheet and the back sheet. And
An absorbent article having a sheet constituting the body-side contact surface and a flap portion to which the back sheet is directly joined,
The back sheet has a breathable polyolefin film, and a nonwoven fabric laminated on the clothing side contact surface of the polyolefin film, and the polyolefin film and the nonwoven fabric are intermittently bonded with a hot melt adhesive. Composite sheet,
The application pattern of the hot melt adhesive in the back sheet is as follows:
In the portion where the back sheet is in contact with the absorber, it consists of straight lines and sawtooth wavy lines that are alternately parallel to the straight lines,
In the flap portion, it consists of a plurality of overlapping circles,
The application area of the hot melt adhesive is
In the part where the back sheet is in contact with the absorber, the area of the plane of the absorber is 4% or more and 15% or less,
In the flap part, it is 0.5% or more and 50% or less of the area of the flap part,
The application amount of the hot melt adhesive is
In the part where the back sheet is in contact with the absorber, it is 5 g / m ² or more and 30 g / m ² or less,
Wherein the flap portion is 10 g / ^{m 2} or more 50 g / ^{m 2} or less, the absorbent article. In the application pattern of the hot melt adhesive in the back sheet, at the site where the back sheet is in contact with the absorber,
Two straight lines adjacent to one sawtooth wave line are separated by 6 mm or more and 30 mm or less,
The amplitude of the sawtooth wavy line is 2.5 mm to 10 mm, the wavelength is 5 mm to 25 mm,
The absorptive article according to claim 1 whose thickness of a straight line and a sawtooth wave line is 0.2 mm or more and 1.5 mm or less. In the application pattern of the hot melt adhesive in the back sheet in the flap portion,
The diameter of a plurality of circles that overlap each other is 5 mm or more and 30 mm or less, and adjacent circles overlap 10% or more and 40% or less of the diameter,
The absorptive article according to claim 1 or 2 whose thickness of the circumference of a plurality of circles which mutually overlap is 0.2 mm or more and 1.5 mm or less.   In the adhesive strength between the polyolefin film and the nonwoven fabric, 180 ° peel strength is 0.9 / 50 mm or more and 2.2 N / 50 mm or less at the portion where the back sheet and the absorber are in contact, and 180 ° at the flap portion. The absorbent article in any one of Claim 1 to 3 whose peel strength is 1.0 N / 50mm or more and 1.5 N / 50mm or less. The absorbent article according to any one of claims 1 to 4, wherein the nonwoven fabric is any one of a spunbond nonwoven fabric, a thermal bond nonwoven fabric, and a composite nonwoven fabric of spunbond nonwoven fabric / melt blown nonwoven fabric / spunbond nonwoven fabric.

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