JP2021052977A - Inner pad type absorbent article - Google Patents

Abstract

To provide an inner pad type absorbent article which is excellent in fitness to a paper diaper as outerwear, a holding property, and detachability, does not need a fastening tape for fastening to the paper diaper, and prevents lateral leakage.SOLUTION: An inner pad type absorbent article includes a liquid permeable top sheet 10, a liquid impermeable back sheet 30, and an absorber 20 arranged between the top sheet 10 and the back sheet 30. The back sheet 30 is constituted of a gas permeable olefine film 301 arranged on a skin side and a pulp including non-woven fabric 302 arranged on a non-skin side. The pulp including non-woven fabric 302 has basis weight of 40 g/m2 or more and 80 g/m2 or less, a thickness of 0.25 mm or more and 0.50 mm or less, an average friction coefficient MIU of 0.08 or more by a friction feeling tester KES-SE, and an average deviation MMD of the average friction coefficient of 0.005 or more. The inner pad type absorbent article is used as an auxiliary pad inside the paper diaper.SELECTED DRAWING: Figure 2

Description

The present invention relates to an inner pad type absorbent article.

Absorbent articles such as disposable diapers are generally composed of a liquid-permeable top sheet, a liquid-impermeable bag sheet, and an absorbent body arranged between the two sheets. By adopting such a configuration and wearing the top sheet so that it is located on the skin side, body fluids such as urine pass through the top sheet of the absorbent article and are absorbed by the absorber, and are externally absorbed by the back sheet. It is designed not to leak to. Generally, adult disposable diapers include a tape stopper type, a pants type, a urine absorbing pad, and the like, and these disposable diapers are appropriately selected and used according to the need for long-term care in excretion of the wearable person.

By the way, tape-stop type and pants-type disposable diapers may be used alone or with a urine absorbing pad inside, but at present, the urine absorbing pad is stacked on the top sheet. In most cases, it is used. This is because the cost per sheet of tape-stop type or pants-type disposable diapers is high, and the urine absorbing pad is cheaper than these. By absorbing and holding excrement with the urine absorbing pad and then replacing only the urine absorbing pad, it is not necessary to replace the tape-stop type or pants type disposable diaper after excretion, and the disposable diaper can be used economically at low cost. it can.

When using a urine absorbing pad as an inner and a tape-stop type or pants type disposable diaper as an outer, in order to effectively prevent the leakage of excrement and to fully demonstrate the absorption performance of the urine absorbing pad, it should be applied to the crotch. It is necessary to have a good fit. In particular, regardless of the gender of the wearer, it is necessary to bring the absorbing surface of the urine absorbing pad into close contact with the urethral meatus of the wearer.

On the other hand, since the urine absorbing pad must absorb a large amount of body fluid such as urine excreted by an adult, a large-sized and large-absorbed urine pad is widely used. For this reason, in order to attach the large urine absorbing pad to the crotch in close contact with the wearer, the urine absorbing pad may be folded vertically into a V-shape or a W-shape, or it may be pulled to the crotch while swinging left and right. It has to be inserted, and it requires skill and familiarity to be worn by the caregiver, and in situations where such skill and familiarity are not used, the wearer is allowed to wear it with good adhesion to the crotch. There was a problem that it could not be done.

Patent Document 1 describes a liquid-permeable top sheet, a liquid-impermeable back sheet, an absorber disposed between the top sheet and the back sheet, and a pair provided on both sides of the absorber in the width direction. It is an inner pad of a disposable diaper provided with the three-dimensional gathers of the above, and is provided on the surface of the crotch part of the pair of three-dimensional gathers in order to prevent the crotch part from rising, the fit to the human body from being lowered, and the leakage of body fluid such as urine. , A first fixing means that is detachably fastened to the inner surface of the three-dimensional gather on the paper diaper side, and a first fixing means that is provided on the ventral and back side surfaces of the back sheet and is detachably fastened to the inner surface of the paper diaper. An absorbent article comprising a second fixing means is disclosed.

Further, in Patent Document 2, in order to easily attach the disposable diaper to the disposable diaper and adjust the position, and without excessively following the movement of the attached clothes, the fit is prevented from being deteriorated and the leakage of body fluid such as urine is prevented. Absorption with fixing means at both widthwise edges on the front and rear sides of the disposable auxiliary pad and areas where no fixing means are present at the crotch and center of the disposable auxiliary pad. Sexual articles are disclosed.

Japanese Unexamined Patent Publication No. 2009-245061 Japanese Unexamined Patent Publication No. 2012-249691

However, in Patent Document 1, although the crotch portion is prevented from floating by the first fixing means provided on the surface of the crotch portion of the pair of three-dimensional gathers of the absorbent article, it is difficult to attach / detach to / from the disposable diaper. , When worn for a long time, the fit is not sufficient in the inflated state after absorption of urine, etc., and there is anxiety about lateral leakage.

On the other hand, in Patent Document 2, fixing means are provided only on both front and rear edges of the disposable auxiliary pad in the width direction, and the adhesion at the crotch is weak, which is as high as seen in recent years. With the large absorbent pad, there is a problem that a space is created between the disposable diaper and the disposable auxiliary pad at the crotch, which leads to lateral leakage due to lack of fixing property.

The subject of the present invention is excellent fit, easy attachment / detachment to / from a disposable diaper, no tape is required for fixing to the disposable diaper, the holdability to the disposable diaper is maintained even when used for a relatively long time, and lateral leakage is maintained. It is to provide an inner pad type absorbent article that can be prevented.

In view of the above problems, the present inventors have conducted diligent research. As a result, they have found that the above-mentioned problems can be solved by the breathable polyolefin film and the inner pad type absorbent article having a back sheet in which a pulp-containing non-woven fabric is laminated on the contact surface of the polyolefin film on the clothes side. The invention was completed.

The present invention provides the following inner pad type absorbent articles (1) to (8) as a preferred embodiment.

(1) The first aspect of the present invention includes a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorber arranged between the top sheet and the back sheet, and is provided inside a paper diaper. An inner pad type absorbent article used as an auxiliary pad, in which a breathable olefin film is arranged on the skin side of the back sheet, a pulp-containing non-woven fabric is arranged on the non-skin side of the back sheet, and the pulp-containing non-woven fabric is arranged. The basis weight is 40 g / m ² or more and 80 g / m ² or less, the thickness is 0.25 mm or more and 0.50 mm or less, and the average friction coefficient MIU by the friction tester KES-SE is 0.08 or more. , An inner pad type absorbent article characterized in that the average deviation MMD of the average friction coefficient is 0.005 or more.
(2) The second aspect of the present invention is the inner pad type absorbent article according to (1), wherein the pulp-containing nonwoven fabric is a composite in which pulp fibers are entangled and integrated with a spunbonded nonwoven fabric made of polypropylene. It is a non-woven fabric.
(3) A third aspect of the present invention is the inner pad type absorbent article according to (1) or (2), wherein the pulp-containing nonwoven fabric is a spunbonded nonwoven fabric made of polypropylene and a spunbonded nonwoven fabric. Includes a layer of pulp fibers entangled and immobilized on at least one surface.
(4) A fourth aspect of the present invention is the inner pad type absorbent article according to any one of (1) to (3), wherein the pulp content of the pulp-containing nonwoven fabric is 65% by mass or more and 90. It is less than mass%.
(5) A fifth aspect of the present invention is the inner pad type absorbent article according to any one of (1) to (4), wherein the breathable polyolefin film has a basis weight of 10 g / m ^2. More than 30 g / m ² or less.
(6) The sixth aspect of the present invention is the inner pad type absorbent article according to any one of (1) to (5), wherein the thickness of the breathable polyolefin film is 15 μm or more and 40 μm or less. is there.
(7) A seventh aspect of the present invention is the inner pad type absorbent article according to any one of (1) to (6), wherein the breathable olefin-based film is a porous olefin-based film. It is at least one or more laminates selected from the group consisting of embossed products and embossed products of breathable olefin films other than porous olefin films.
(8) An eighth aspect of the present invention is the inner pad type absorbent article according to any one of (1) to (7), wherein the breathable polyolefin film is a breathable polyethylene film.

According to the present invention, it has excellent fit, is easy to put on and take off from a disposable diaper, does not require tape to be fixed to the disposable diaper, maintains the holdability to the disposable diaper even after being used for a relatively long time, and prevents lateral leakage. An inner pad type absorbent article that can be prevented can be provided.

It is a top view which shows one embodiment of the absorbent article of this invention schematically. It is a schematic cross-sectional view in _X 1 -X ₁ section line of Figure 1.

Hereinafter, embodiments for carrying out the present invention (hereinafter, also referred to as “embodiments”) will be described in detail with reference to the accompanying drawings, but these are listed for the purpose of exemplification, and the present invention is limited thereto. It's not something to do. The same elements are designated by the same reference numerals throughout the description of the embodiments.

As used herein, the term "when the absorbent article is worn" means at least one of the time when the absorbent article is worn and the time after the absorbent article is worn. 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 reference numeral X in the drawing. On the contrary, the width direction or the lateral direction of the absorbent article is a direction orthogonal to the longitudinal direction, and is a direction indicated by reference numeral Y in the drawing. The body-side contact surface is the surface of the front and back surfaces of each member such as the absorber that is arranged on the wearer's skin side when worn, and the clothing-side contact surface is the front and back surfaces of each member such as the back sheet. Of these, the surface is directed to the side opposite to the wearer's skin side when worn. Body fluid refers to the liquid excreted from the body such as urine, sweat, blood and water in loose stool. Absorbent articles include those that absorb body fluids, such as tape-stopping disposable diapers, pants-type disposable diapers, urine absorbing pads, light incontinence pads, sanitary napkins, etc., regardless of whether they are for infants or adults. Can be mentioned.

<Absorbent article>
FIG. 1 is a plan view of the inner pad type absorbent article 1 (hereinafter, also simply referred to as “absorbent article 1”) according to the present embodiment as viewed from the top sheet 10 side (upper surface side), and FIG. 2 is a view. It is sectional drawing in the X _1- X _{1 cutting line of 1.}
As shown in FIGS. 1 and 2, the absorbent article 1 of the present embodiment has a liquid-permeable top sheet 10 (hereinafter, also simply referred to as “top sheet 10”), an absorber 20, and the absorbent body 20 from the skin contact surface side. A liquid-impermeable back sheet 30 (hereinafter, also simply referred to as “back sheet 30”) is provided in this order, and a three-dimensional gather 40 is further provided.

In the present embodiment, the top sheet 10 is provided so as to cover the body-side contact surface of the absorber 20 and both end faces in the width direction, and the back sheet 30 is provided so as to cover the clothing-side contact surface of the absorber 20 in the present embodiment. However, but not limited to this, any known absorbent article, particularly the arrangement of the top sheet and the back sheet in the urine absorbing pad, can be adopted.

In the present embodiment, the absorber 20 is covered with the top sheet 10 and the back sheet 30, but the absorber 20 is not limited to this, and for example, the absorber 20 is a super absorbent polymer, hereinafter referred to as “SAP”. In the case of a liquid-absorbent sheet containing particles (also referred to as), the absorber 20 is wrapped with one or more carrier sheets (not shown) from the viewpoint of preventing leakage of SAP particles and stabilizing the shape of the absorber 20. It may be in the form. At this time, the carrier sheet may be any one having hydrophilicity, and examples thereof include hydrophilic non-woven fabrics such as tissue, absorbent paper, and air-laid non-woven fabric. When the absorber 20 includes a plurality of carrier sheets, the base materials constituting the carrier sheet may be the same or different. Details of SMP will be described later.

Further, in the present embodiment, the top sheet 10 covers the entire body side surface of the absorber 20, but the present invention is not limited to this, and a part of the skin side surface may be exposed. For example, a form in which both edges of the side surface of the skin on the Y-direction side are exposed can be mentioned.

In the present embodiment, the three-dimensional gather 40 is directed toward the top sheet 10 side from both ends in the width direction of the clothing side contact surface of the back sheet 30 with respect to the laminated body of the top sheet 10, the absorber 20, and the back sheet 30. Therefore, it is erected so as to cover both end faces in the width direction of the laminated body, and has a function of preventing body fluid leakage from, for example, the absorber 20. In addition, in FIG. 1 and FIG. 2, it is described that the tip portion of the three-dimensional gather 40 on the top sheet 10 side is bent so as to face the top sheet 10, which indicates that the three-dimensional gather 40 is bendable. This is a thing, and does not limit the shape of the three-dimensional gather 40. The three-dimensional gather 40 is not limited to this embodiment, and may be fixed to any part of the laminated body, such as both end faces in the width direction of the back sheet 30 and both end faces in the width direction of the absorber 20. As the three-dimensional gather 40, conventionally known materials and structures can be used and fixed to the laminated body in the same manner as before.

Next, the top sheet 10, the absorber 20, and the back sheet 30 will be described in detail.

[Top sheet 10]
The top sheet 10 of the present embodiment is composed of a liquid-permeable base material through which body fluid moves to the absorber 20. Examples of such a base material include a non-woven fabric such as a thermal bond non-woven fabric and an air-through non-woven fabric, a composite non-woven fabric in which a thermal bond non-woven fabric / spunbond non-woven fabric is laminated, an open film such as an opening polyethylene film, polyethylene foam, and urethane foam. Examples thereof include a foamed film and a composite sheet which is a laminate of two or more of these. The thickness of the top sheet 10 is not particularly limited, but an example thereof is 0.20 mm or more and 1.0 mm or less.

The surface of the top sheet 10 is preferably embossed or perforated in order to improve liquid permeability, and the embossing or perforation can be performed by a conventionally known method. In order to reduce the irritation of the top sheet 10 to the skin, 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 moisturizer and the like.

The basis weight of the top sheet 10 is not particularly limited, but is preferably 14 g / m ² or more and 40 g / m ² or less from the viewpoint of strength and workability. If it is smaller than 14 g / m ² , it tends to be easily damaged during the production of the absorbent article 1, and if it is ^{larger than 40 g / m 2} , it tends to feel hardness when it hits the skin. The shape of the top sheet 10 is not particularly limited, but it may be a shape that covers the absorber 20 in order to guide the body fluid to the absorber 20 so as not to leak.

[Absorbent 20]
The absorber 20 has, for example, a function of absorbing and retaining body fluid. Specific examples of the absorber 20 include a liquid-absorbing sheet, a sheet made of SAP, a liquid-absorbing sheet containing SAP, and the like. Among these, a liquid absorbent sheet containing SAP is preferable.

The liquid-absorbing sheet is not particularly limited as long as it is used for absorbent articles such as sanitary napkins, diapers, and urine absorbing pads in this field. For example, fluff pulp, cotton, rayon, acetate, tissue, etc. A sheet composed of one or more materials such as absorbent paper and hydrophilic non-woven fabric. Among these materials, fluff pulp is preferable from the viewpoint of absorbability. Examples of the fluff pulp include those obtained by defibrating wood pulp, synthetic fiber, polymer fiber, non-wood pulp and the like into a cotton-like shape. These fluff pulps can be used alone or in combination of two or more. The basis weight of the liquid-absorbent sheet 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. If it is smaller than 100 g / m ² , the amount of body fluid absorbed tends to be small, and ^{if it is larger than 800 g / m 2,} it tends to be difficult to stably produce the absorber 20.

The SAP is not particularly limited as long as it can absorb body fluid and prevent backflow of body fluid. For example, polyacrylic acid salt, polyaspartate, and (starch-acrylic acid) graft copolymer weight. Examples thereof include polymers containing a carboxyl group-containing monomer such as a coalescence, a (acrylic acid-vinyl alcohol) copolymer, a (isobutylene / maleic anhydride) copolymer and a saponified product thereof. SAP can be used alone or in combination of two or more. Among these SAPs, polyacrylate is preferable, and sodium polyacrylate is more preferable, from the viewpoint of the amount of body fluid absorbed per weight. The basis weight of the sheet made of SAP is preferably ^{50 g / m 2} or more and 500 g / m ^{2 or less from the viewpoint of improving absorption performance and touch.} If it is smaller than 50 g / m ^2, it tends to be difficult to absorb body fluids, especially urine, and ^{if it is larger than 500 g / m 2} , the loss in the manufacturing process of the sheet made of SAP tends to increase.

The liquid-absorbing sheet containing SAP is not particularly limited, but a liquid-absorbing sheet mixed with SAP particles, a SAP sheet in which SAP particles are fixed between the liquid-absorbing sheets, and the like are preferable. In addition, there are liquid-absorbent sheets containing SAP in the form of fibers.

The shape of the absorber 20 is not particularly limited, and examples thereof include a rectangular shape, an hourglass shape, and an I shape. The absorber 20 may be used by stacking two or more layers. The thickness of the absorber 20 is appropriately selected according to the type of body fluid to be absorbed, the form and material of the absorber 20, and the absorbability and retention of the body fluid, and the wearing of the absorbent article 1. From the viewpoint that a person can operate without discomfort even after absorbing body fluid, the thickness is preferably 2.0 mm or more and 50.0 mm or less.

[Backsheet 30]
In the present embodiment, the back sheet 30 contains a breathable polyolefin film 301 located on the body side and a pulp located on the clothing side and having a predetermined basis weight, average friction coefficient MIU, and average deviation MMD of average friction coefficient. A laminate with the non-woven fabric 302 is used. As a result, the adsorptive article 1 can be stably fixed to a disposable diaper (outer) such as a tape stopper type or a pants type without using a tape. When attaching the absorbent article 1 to an outer such as a disposable diaper, it does not require the skill of a caregiver, it is easy to put on and take off, the troublesomeness of using the tape is eliminated, and the skin is significantly damaged by the rubbing of the tape. It is suppressed. Further, even if the absorbent article 1 is worn for a relatively long time, it maintains good holdability on the outer such as paper pants, and even if it operates with the absorbent article 1 attached before and after absorbing the body fluid. There is very little discomfort.

The back sheet 30 used in the absorbent article 1 of the present embodiment includes a breathable polyolefin film 301 and a non-woven fabric 302 laminated on the clothing side surface of the polyolefin film 301, and includes the polyolefin film 301 and the non-woven fabric 302. It is a composite sheet in which the non-woven fabric 302 is intermittently adhered. By intermittently adhering, for example, the air permeability between the polyolefin-based film 301 and the pulp-containing non-woven fabric 302 is improved, and stuffiness or the like in the state where the absorbent article 1 is attached is reduced. In the embodiment, the polyolefin-based film 301 and the non-woven fabric 302 are intermittently bonded, but the present invention is not limited to this, and the entire surface may be bonded. These bonding methods are not particularly limited, and examples thereof include bonding with a hot melt adhesive and pressure bonding.

(Breathable polyolefin film 301)
The breathable polyolefin film 301 is not particularly limited as long as it has waterproofness and moisture permeability. For example, a polyolefin-based resin and an inorganic filler such as calcium carbonate are melt-kneaded to form a film. Examples thereof include a porous polyolefin-based film obtained by uniaxially or biaxially stretching this film and an embossed product thereof, and an embossed product of a breathable polyolefin-based film other than the porous polyolefin-based film. Examples of the polyolefin-based resin include polyethylene, polypropylene, polybutene and the like, and these can be used alone or in combination. Among the films using these polyolefin-based resins, the breathable polyolefin-based film 301 is preferably a breathable polyethylene-based film from the viewpoint of water resistance and breathability.

The thickness of the breathable polyolefin film 301 is not particularly limited, but is preferably 15 μm or more and 40 μm or less, and more preferably 20 μm or more and 30 μm or less. If it is thinner than 15 μm, the strength tends to be low, and if it is thicker than 40 μm, the polyolefin-based film tends to be hard, and in either case, the performance of the absorbent article 1 may be affected.

The thickness of the breathable polyolefin film 301 was measured using a thickness gauge (trade name: dial thickness gauge "PEACOCK (trade name)" manufactured by Ozaki Seisakusho Co., Ltd.). The measurement conditions are 35 gf / cm ² (measurement load 250 gf, stylus diameter 30 mm), 10 breathable polyolefin films 301 are placed on top of each other between the stylus and the measuring table, and the stylus is 1 mm or less per second. The gauge when dropped at a speed was read, and this was divided by 10, and the thickness per sheet was calculated.

The basis weight of the breathable polyolefin film 301 is not particularly limited, but is preferably ^{10 g / m 2} or more and 30 g / m ^{2 or less.} If it is smaller than 10 g / m ² , the strength tends to be low, and if it is ^{larger than 30 g / m 2} , the polyolefin-based film tends to be hard.

(Pulp-containing non-woven fabric 302)
As the pulp-containing non-woven fabric 302 (hereinafter, also simply referred to as “nonwoven fabric 302”) used in the back sheet 30 of the present invention, wood pulp fibers are entangled and integrated with a spunbonded non-woven fabric made of polypropylene by a water jet without using a binder. A composite non-woven fabric made of is preferable. In this composite non-woven fabric, for example, a layer of wood pulp fibers bonded to the non-woven fabric by entanglement is formed on one surface of a polypropylene spunbonded non-woven fabric, and the wood pulp fibers are also entangled on the other surface. May be combined by. That is, a preferred form of the pulp-containing non-woven fabric 3 is a form in which at least one surface of the non-woven fabric and the non-woven fabric includes a wood pulp fiber layer which has been subjected to water flow entanglement integration treatment. In this form, it is preferable that the wood pulp fiber layer is arranged so as to face the clothing side. Here, examples of the wood pulp fiber include fluff pulp, softwood kraft pulp, and the like, and one of these can be used alone or in combination of two or more.

The content of wood pulp in the non-woven fabric 302 is preferably 65% by mass or more and 90% by mass or less, and more preferably 70% by mass or more and 85% by mass or less. If it is less than 65% by mass, the material and performance of the obtained pulp-containing nonwoven fabric tend to be non-uniform, and if it exceeds 90% by mass, the obtained pulp-containing nonwoven fabric becomes hard and lacks flexibility, according to the present embodiment. The fit of the absorbent article 1 tends to decrease.

The basis weight of the pulp-containing non-woven fabric is 40 g / m ² or more and 80 g / m ² or less, preferably 42 g / m ² or more and 78 g / m ² or less. If it is less than 40 g / m ² , it tends to be too soft when used for the back sheet 30, and if it ^{exceeds 80 g / m 2} , it tends to be too hard when used for the back sheet 30. In either case, the fit and holdability of the absorbent article 1 may be affected.

The thickness of the pulp-containing non-woven fabric is preferably 0.25 mm or more and 0.50 mm or less, and more preferably 0.30 mm or more and 0.45 mm or less when measured by the method using the above-mentioned "PEACOCK". If the value is lower than 0.25 mm, the back sheet 30 becomes too soft, the back sheet 30 is not stably fixed during manufacturing, and the manufacturing yield tends to decrease. Further, when the value is higher than 0.50 mm, the back sheet 30 becomes hard and tends to affect the fit and holdability of the absorbent article 1.

(Average friction coefficient MIU and average deviation MMD of average friction coefficient)
In the absorbent article 1 of the present embodiment, the friction feeling tester KES-SE (manufactured by Kato Tech Co., Ltd.) of the pulp-containing non-woven fabric 302 used for the back sheet 30 has an average friction coefficient MIU of 0.08 or more and an average average friction coefficient. The deviation MMD is preferably 0.005 or more. The higher the value of the average friction coefficient MIU, the less slippery it is, and the higher the value of the average deviation MMD of the average friction coefficient, the lower the smoothness and the greater the roughness.

If the average coefficient of friction MIU is less than 0.08 or the average deviation MMD of the average friction coefficient is less than 0.005, it is not preferable because the back sheet feels too smooth and cannot be attached to an outer such as a pants-type disposable diaper. ..

In the present invention, by adjusting the average friction coefficient MIU and the average deviation MMD of the average friction coefficient of the pulp-containing non-woven fabric 302 used for the backsheet 30 within the above numerical ranges, the height direction (in FIG. 1). It is possible to improve the texture (in the direction perpendicular to the plane formed in the X and Y directions).

The method for measuring the average friction coefficient MIU and the average deviation MMD of the average friction coefficient is as follows. Using the friction tester KES-SE (manufactured by Kato Tech Co., Ltd.), the sample is placed on a smooth metal plane, and the speed is 0.1 cm / sec for a region of 0.5 cm in width and 2 cm in length on the sample. The average friction coefficient MIU and the average deviation MMD of the friction coefficient are measured while moving the contactor horizontally at a constant speed of. As the contactor, ten 0.5 mm piano wires are arranged side by side, and the load applied to the contactor is 25 gf.

(Method of manufacturing back sheet 30)
An example of the manufacturing method of the bag sheet 30 is shown. The back sheet 20 may be produced by adhering the breathable polyolefin film 301 and the non-woven fabric 302 with a hot melt adhesive. More specifically, for example, the hot melt adhesive is transferred to the non-woven fabric 302 by a transfer roll having a letterpress portion formed so as to have a predetermined coating pattern, and the breathable polyolefin film 301 is set on the transfer roll. Then, the back sheet 30 can be produced by heating and / or pressurizing the laminated product for a predetermined time to integrate them. At this time, the non-woven fabric 302 is bonded to the breathable polyolefin film 301 in a state of being stretched in the width direction or the length direction in the range of 2% or more and 10% or less, and then the shape of the non-woven fabric 302 is restored by tension. As a result, voids that contribute to the improvement of breathability are formed between the breathable polyolefin film 301 and the non-woven fabric 302.

Although the present invention has been described above using the embodiments, it goes without saying that the technical scope of the present invention is not limited to the scope described in the above-described embodiments and examples. It will be apparent to those skilled in the art that various changes or improvements can be made to the above embodiments. Further, it is clear from the description of the scope of claims that the form to which such a modification or improvement is added may be included in the technical scope of the present invention.

Hereinafter, the present invention will be described in detail with reference to examples. The present invention is not limited to the examples shown below.

<Example 1>
(Creation of fluff pulp non-woven fabric)
As the fluff pulp non-woven fabric, a hydro-knit non-woven fabric under the trade name of Kimberly-Clark Co., Ltd. in the United States was used. As disclosed in US Pat. No. 5,284,703, the fluff pulp non-woven fabric is a polypropylene non-woven fabric in which pulp is entangled with water to form a sheet. In the first embodiment, the basis weight is 40 g / m ² and the thickness is 30 μm. I used the one.
(Creation of backsheet)
The application pattern of the hot melt adhesive of the styrene / butadiene / styrene copolymer was transferred to the fluff pulp-containing non-woven fabric, and the breathable polyethylene film (basis weight: 15 g / m2, thickness 23 μm) was set on it. .. A back sheet was prepared by integrating the fluff pulp-containing non-woven fabric and the breathable polyethylene film. The ratio of the coating area of the hot melt adhesive was 4.8% at the portion in contact with the absorber.

(Creation of absorbent articles)
The back sheet obtained above, the air-through non-woven fabric (basis weight 20 g / m ² ) as the top sheet, and the laminate of 27 g of fluff pulp and 12 g of SAP (sodium polyacrylate) as the absorber are lengthened in the X direction in FIG. Using the ones cut to a length of 42 cm and a width of 15 cm in the Y direction of FIG. 1, the absorber was covered with a top sheet and a back sheet, and the length of 48 cm in the X direction of FIG. 1 and the width of 19 cm in the Y direction of FIG. An inner pad type absorbent article (urine absorbing pad) was produced.

<Examples 2 to 4, Comparative Examples 1 to 2>
When laminating a breathable polyethylene-based film and a pulp-containing non-woven fabric, the pulp content (%), basis weight (g / m ² ), thickness (mm), average friction coefficient MIU or average deviation MMD of the pulp-containing non-woven fabric are determined. Either change (Examples 2 to 4 and Comparative Example 1) or use a polypropylene spunbonded non-woven fabric (Comparative Example 2) instead of the pulp-containing non-woven fabric, and in the same manner as in Example 1, Examples 2 to 4 and Comparative Example. 1-2 inner pad type absorbent articles (urine absorbing pads) were produced.

<Average friction coefficient MIU and average deviation MMD of average friction coefficient>
With respect to the inner pad type absorbent articles obtained in Examples 1 to 4 and Comparative Examples 1 and 2, the average friction coefficient MIU and the average friction of the pulp-containing non-woven fabric constituting the clothing side of the back sheet were used by using the above-mentioned method. The mean deviation MMD of the coefficients (simply referred to as "mean deviation MMD" in Table 1) was measured by the method described above and the results are shown in Table 1.

<How the inner pad type absorbent article is attached to the disposable diaper>
In order to confirm the attachment condition (holdability) of the inner pad type absorbent articles of Examples 1 to 4 and Comparative Examples 1 to 2 to the disposable diapers, sensory evaluation was performed by 20 panelists. The inner pad type absorbent article was attached as the inner of the pants type paper diaper (outer), and the catch of the inner pad type absorbent article was confirmed and evaluated according to the following criteria, and the results are shown in Table 1. In Table 1, this test item is referred to as "mounting / holding property".
〇: 16 or more and 20 or less evaluators who "feel that they are installed without problems".
Δ: 11 or more and 15 or less evaluators who “felt that they were installed without problems”.
×: The number of evaluators who "feel that they are installed without problems" is 10 or less.

<Stiffness when the inner pad type absorbent article is attached to a disposable diaper>
Sensory evaluation was performed by 20 panelists in order to confirm the feeling of stiffness when the inner pad type absorbent articles of Examples 1 to 4 and Comparative Examples 1 and 2 were attached to the disposable diapers. The inner pad type absorbent article was attached as the inner of the pants type disposable diaper, and the stiffness of the inner pad type absorbent article was confirmed and evaluated according to the following criteria, and the results are shown in Table 1. In Table 1, this test item is referred to as "stiffness".
〇: 16 or more and 20 or less evaluators who "feel uncomfortable".
Δ: 11 or more and 15 or less evaluators who “feeled uncomfortable”.
×: There are 10 or less evaluators who "feel not stiff".

<Uncomfortable feeling when wearing>
The inner pad type absorbent articles of Examples 1 to 4 and Comparative Examples 1 and 2 were used as inners of pants-type disposable diapers by 10 panelists who wear disposable diapers on a daily basis overnight (10 hours) to urinate. We received answers regarding the quality of the fit after absorption and the presence or absence of lateral leakage. Based on the answers, the evaluation was made according to the following criteria and shown in Table 1.
◯: “There was no discomfort after absorption of urination” and “There was no lateral leakage even after wearing it overnight” was 8 or more and 10 or less.
Δ: “There was no discomfort after absorption of urination” and “There was no lateral leakage even after wearing it overnight” was 5 or more and 7 or less.
×: 4 or less, "I did not feel any discomfort after absorbing urine" and "I did not have lateral leakage even if I wore it overnight".

As shown in Table 1, when the pulp-containing non-woven fabric is used for the outermost part of the back sheet (clothing side), when it is attached to the pants-type disposable diaper as an inner pad-type absorbent article, it is excellent in catching, so that the holdability for the pants-type disposable diaper is improved. It can be seen that it is maintained and there is little feeling of stiffness. In addition, there is little discomfort when actually wearing it.

On the other hand, in Comparative Example 1 in which the pulp-containing non-woven fabric is thick, it is not preferable because it causes a feeling of stiffness when it is attached to a pants-type disposable diaper. .. Further, in Comparative Example 2 using the spunbonded non-woven fabric, the slipperiness is good, so that the holdability to the pants-type disposable diaper is poor, and the diaper is displaced when worn, which is not preferable.

1 Absorbent article 10 Top sheet 20 Absorbent 30 Back sheet 301 Breathable polyolefin film 302 Pulp-containing non-woven fabric 40 Three-dimensional gather

Claims (8)

An inner pad type absorbent that includes a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorber arranged between the top sheet and the back sheet, and is used as an auxiliary pad inside a disposable diaper. It ’s an article,
A breathable olefin film is placed on the skin side of the back sheet, and a pulp-containing non-woven fabric is placed on the non-skin side of the back sheet.
The pulp-containing non-woven fabric has a basis weight of 40 g / m ² or more and 80 g / m ² or less, a thickness of 0.25 mm or more and 0.50 mm or less, and an average friction coefficient MIU by the friction tester KES-SE. An inner pad type absorbent article characterized in that the average deviation MMD of the average friction coefficient is 0.005 or more and 0.08 or more. The inner pad type absorbent article according to claim 1, wherein the pulp-containing non-woven fabric is a composite non-woven fabric in which pulp fibers are entangled and integrated with a spunbonded non-woven fabric made of polypropylene. The inner according to claim 1 or 2, wherein the pulp-containing nonwoven fabric includes a spunbonded nonwoven fabric made of polypropylene and a layer of the pulp fibers entangled and immobilized on at least one surface of the spunbonded nonwoven fabric. Pad-type absorbent article. The inner pad type absorbent article according to any one of claims 1 to 3, wherein the pulp content of the pulp-containing non-woven fabric is 65% by mass or more and 90% by mass or less. The inner pad type absorbent article according to any one of claims 1 to 4, wherein the breathable polyolefin film has a basis weight of 10 g / m ² or more and 30 g / m ^{2 or less.} The inner pad type absorbent article according to any one of claims 1 to 5, wherein the thickness of the breathable polyolefin film is 15 μm or more and 40 μm or less. The breathable olefin-based film is at least one or more selected from the group consisting of a porous olefin-based film, an embossed product thereof, and an embossed product of a breathable olefin-based film other than the porous olefin-based film. The inner pad type absorbent article according to any one of claims 1 to 6, which is a laminated body. The inner pad type absorbent article according to any one of claims 1 to 7, wherein the breathable polyolefin film is a breathable polyethylene film.

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