JP2003284741A - Absorbent goods - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely maintain adhesive agent layers on opposite faces while enabling body fluid diffusion on skin side faces of flap parts to be suppressed. <P>SOLUTION: In a sanitary napkin 1 having a main body part with a body fluid absorbent part and flap parts F1, F2 set around the main body part, the flap parts F1, F2 have embossed depression parts eb on the skin side faces and do not substantially have projections and depressions on rear faces of the flap parts F1, F2, and the adhesive agent layers are provided at the rear faces of the flap parts F1, F2. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an absorbent article such as a disposable diaper or a sanitary napkin having a body portion having a body fluid absorbing portion and a flap portion provided around the body portion.

[0002]

2. Description of the Related Art The flap portion of this type of absorbent article is of the type that is folded back to the outer surface of shorts (hereinafter also referred to as the folded flap portion), as is often seen in sanitary napkins, and for long-term sanitary products. It is not folded back to the outside of the shorts as often seen in napkins and disposable diapers,
There is one that is used by being extended so as to come into contact with the skin surface and to receive the leakage of body fluid around the body portion (hereinafter, also referred to as a cover flap portion). The two are clearly distinguished conceptually and functionally. That is, the former has the main function of fixing the article to the shorts, and the latter has the main function of preventing the body fluid leaking from the main body from transferring to clothes such as shorts. Usually, an adhesive layer is formed on the back surface (exterior surface) of these flap portions to prevent misalignment.

By the way, the applicant of the present invention provides a liquid stop concave portion on the skin side surface of the cover flap portion by embossing or the like, so that even if the body fluid leaks from the body portion side onto the cover flap portion, It was found that the liquid stop recess formed on the surface can suppress the diffusion of body fluid.

[0004]

However, when embossing is applied to the cover flap portion, unevenness is formed on both the front and back surfaces of the cover flap portion. There is a problem that the contact area between the layer and the back surface of the flap portion is small, the adhesive is held in a state of floating on the flap surface, and the adhesive is transferred to the shorts.

When the flap portion is embossed, it becomes harder than necessary, and when it is worn by the wearer, the skin (especially in the sanitary napkin having the folded flap portion, the inside of the thigh base) There is also a problem that the user feels a sense of incongruity due to rubbing between the skin) and the flap portion, or that a rash occurs on the portion rubbing against the flap portion.

[0006] Therefore, a main object of the present invention is to provide an absorbent article having a flap portion in which the pressure-sensitive adhesive does not easily transfer to the shorts, while adopting a form for suppressing the body fluid diffusion by the embossed concave portion. Another object is to provide an absorbent article having a flap portion in which problems such as the above-mentioned discomfort and rash are less likely to occur.

[0007]

The present invention, which has solved the above-mentioned problems, provides an absorbent article having a main body portion having a body fluid absorbing portion and a flap portion provided around the main body portion, wherein at least the flap portion comprises: An absorbent article, characterized in that it has an embossed concave portion on the skin side surface and is configured so as not to have irregularities substantially on its back surface, and an adhesive layer is provided on the back surface of this flap portion. Is.

According to this structure, since the back surface of the flap portion has substantially no unevenness, the pressure-sensitive adhesive layer is surely held in close contact with the back surface, and even if the surface of the pressure-sensitive adhesive layer is adhered to the shorts. It is unlikely that a part of the adhesive will move (remain) to the shorts upon removal.

On the other hand, when embossing is applied to the flap portion, the elasticity of the flap becomes unnecessarily strong, which may cause problems such as discomfort and fogging in the wearer.
However, according to the studies of the present inventors, this problem can be solved by adopting embossing that satisfies at least one of the following requirements (a) to (d). (A) The area ratio of the embossed concave portion to the flap portion is 5 to 80%. (B) The depth of the embossed recess is 0.01 mm or more. (C) The flap portion is formed by laminating a non-woven fabric and a polyethylene sheet, and has an average bending rigidity of 0.03 to 0.10 gcm ² / cm. (D) The opening width of the embossed recess is 0.7 mm or more. (E) A large number of the embossed concave portions are formed in the plane direction of the flap portion with different number densities.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below in detail with reference to application examples to a sanitary napkin shown in the accompanying drawings. The present invention can be applied to disposable paper diapers having a flap portion, various body fluid absorption pads such as urine leakage pads, etc., but description thereof is omitted because those skilled in the art can easily understand the application. To do. FIG. 1 shows a body fluid absorbing side surface of a sanitary napkin 1 according to the present invention in a deployed state, FIG. 2 shows an opposite surface thereof, that is, an exterior surface, and FIG. 3 shows a III-III cross section of FIG. Shows. The sanitary napkin 1 has a liquid-impermeable backsheet 2 made of a polyethylene sheet, a polypropylene sheet, or the like, and a liquid-permeable topsheet 3 that allows quick permeation of menstrual blood and vaginal discharge. An absorbent core 4 made of cotton-like pulp or synthetic pulp is provided in the widthwise center between the two sheets 2 and 3, and a crepe paper wrapping the absorbent core 4 in order to maintain the shape of the absorbent core 4 and improve the diffusivity. An absorber AB including 5 is interposed. The central portion of the product that exhibits this absorbing function constitutes the main body of the present invention.

In this embodiment, the liquid-permeable top sheet 3 has a shape in which the absorber AB is slightly scaled up, and is arranged so as to cover the entire surface of the absorber AB. The liquid-impervious backsheet 2 has the same shape as the plane shape of the product, and both side portions thereof are extended laterally beyond both side edges of the absorbent body AB. The side sheets 6 and 6 made of nonwoven fabric are laminated and bonded so as to cover the. As the joining method, adhesion with a hot melt adhesive, ultrasonic sealing, heat fusion, thermocompression bonding, or a combination thereof can be adopted.

In particular, as shown in the figure, the peripheral edge of the product, specifically the free edges of the back sheet 2 and the laminated portions of the side sheets 6 and 6, the liquid permeable top sheet 3 and the liquid impermeable back sheet 2 It is preferable that the front and rear edges be firmly joined by heat sealing b1 and b2. It is desirable to secure the width of the joint edge at least about 2 mm or more and less than 10 mm. In the illustrated form, the former heat seal b1 is configured so that no unevenness appears on the skin surface side.

In the present embodiment, particularly the crotch portion and the hip portion of the laminated portion of the liquid-impervious backsheet 2 and the side sheets 6 and 6 are greatly extended to the side of the absorbent body AB, and each of these extensions is extended. A folded back flap portion F1 and a hip cover flap portion F2 are formed by the projecting portion. In the present invention, it is possible to adopt a mode in which only one of the flaps is provided or a mode in which the present invention is applied to only one of the flaps.

As shown in FIGS. 2 and 3, a pressure-sensitive adhesive layer 20 is formed on the back sheet 2 on the back surfaces of the flaps F1 and F2, whereby the shorts are fastened. The flap portions F1 and F2 can be folded to the back surface of the main body portion and adhesively fixed to the back surface of the main body portion at the product providing stage. In this case, the cover flap portion F2 is returned so as to come into contact with the skin surface at least in the use state as described above.

In this embodiment, the side sheets 6 and 6 having a large number of recesses eb formed by embossing are
It is joined to the back sheet 2 which has not been subjected to a concavo-convex forming process such as embossing. Therefore, as is clear from the comparison between FIG. 1 and FIG. 2, the flap portions F1 and F2 have the concave portion eb on the skin surface side, but substantially have no unevenness on the opposite surface (back surface). Thus, the pressure-sensitive adhesive layer 20 can be brought into close contact with the backsheet 2 and held securely, and even if the pressure-sensitive adhesive layer 20 is adhered to the outer surface of the shorts and then removed, a part of the pressure-sensitive adhesive layer 20 remains on the outer surface of the shorts. Such a situation is unlikely to occur.

Moreover, since a large number of embossed recesses eb are formed on the surface of the cover flap portion F2, even if the body fluid leaks to the side without being absorbed and held in the body portion, the body fluid is not absorbed. Diffusion is suppressed by the recess eb of F2. Although the recessed portion eb is eventually formed on the surface of the folded flap portion F1, the folded flap portion F1 is folded back to the outside of the shorts, so that the bodily fluid hardly leaks there and the diffusion suppressing function is provided. Does not make any substantial sense. However, the recess eb may be formed in the folding flap portion F1 in this manner due to the manufacturing method or the like.

In particular, as in this embodiment, the side seat 6,
When 6 is made of a non-woven fabric, the body fluid leaking to the side of the main body is diffused by permeating into the side sheet non-woven fabrics 6, 6, and this diffusion is also caused by the embossed recess e.
This is prevented by the sealing effect of b. This function is exhibited regardless of the viscosity of body fluid. Moreover, the side sheet nonwoven fabrics 6 and 6 have not only the function of suppressing the diffusion of body fluid but also a function of absorbing and retaining body fluid.

Further, when the skin side surfaces of the flap portions F1 and F2 are made of non-woven fabric as described above, the flap portions F1 and F2 are
Since the skin surface side has a good touch, the wearer has an advantage that it is less likely to feel a sense of discomfort due to rubbing with the flap portions F1 and F2, and that the portion rubbing with the flap portions F1 and F2 is less likely to have a rash.

By the way, the stiffness of the flaps F1 and F2 has a more significant influence than the type of material with respect to the problems such as discomfort and fogging. Especially as mentioned above, the flap F
Embossing eb, eb on the skin side surface of 1, F2
When applied, the elasticity of the flap portions F1 and F2 tends to be harder than necessary. Therefore, the following (A) to (E) are preferable.
Among them, by performing embossing that selectively satisfies one or more requirements, the flap portion F1 is provided to the extent that the problem of discomfort and fogging described above is reduced or eliminated while having the function of preventing body fluid flow by embossing. , F2 stiffness can be adjusted. (A) The area ratio of the embossed concave portions to the flap portions F1 and F2 is 5 to 80%, preferably 10 to 30%. (B) The depth of the embossed recess is 0.01 mm or more, preferably 0.03 mm or more. (C) When the flaps F1 and F2 are formed by laminating a non-woven fabric and a polyethylene sheet, embossing is applied so that the average flexural rigidity is 0.03 to 0.10 gcm ² / cm. (D) The opening width of the embossed recess is 0.7 mm or more. (E) The density of the number of embossed concave portions is changed in the plane direction of the flap portions F1 and F2. For example, the folded flap portion F1
In the vicinity of the fold line, the number of embossed recesses is relatively reduced and the stiffness is reduced.

On the other hand, the structure and material of the illustrated sanitary napkin 1 will be described in more detail.
The skin side surfaces of 1 and F2 are preferably formed of a non-woven fabric as described above, but like a polyethylene sheet,
It can also be formed by a liquid-permeable or liquid-impermeable sheet of another material used in this kind of field. That is, in the illustrated form, not only the back sheet 2 but also the side sheet 6 can be formed of a liquid impermeable sheet.

Particularly when the side sheets 6 and 6 are made of non-woven fabric, a bulky non-woven fabric such as an air-through non-woven fabric is desirable for the reasons described above. As the non-woven fabric, a water-repellent treated non-woven fabric or a hydrophilic treated non-woven fabric can be used alone or in combination depending on the function to be emphasized. For example, if importance is attached to functions such as preventing the penetration of menstrual blood and vaginal discharge, or enhancing the feeling of touch, a water-repellent treatment coated with a silicone-based, paraffin-based, or alkylchromic chloride-based water repellent. If a non-woven fabric is used and the absorbability of menstrual blood etc. in the flap is emphasized, a compound having a hydrophilic group in the synthetic fiber manufacturing process,
For example, it is synthesized by a method of polymerizing coexistence of an oxidation product of polyethylene glycol or a method of treating with a metal salt such as stannic chloride to partially dissolve the surface to make it porous and deposit a metal hydroxide. A hydrophilic treated non-woven fabric is used in which the fibers are swollen or porous and the capillarity is applied to impart hydrophilicity. However, in the present invention, it is desirable to use a hydrophilic treated non-woven fabric as the non-woven fabric used for the side sheet 6 from the viewpoint described above. As such a non-woven fabric, a natural fiber, a synthetic fiber, a regenerated fiber or the like, which is formed by an appropriate processing method, can be used, but a non-woven fabric having a breathable property by suppressing a basis weight is preferable. Good to use.

The embossing pattern applied to the skin side surfaces of the flaps F1 and F2 preferably satisfies the above requirements (A) to (E), but is basically arbitrary. The embossed pattern may be one in which a large number of recesses are arranged intermittently as shown in the figure, or may be one that is linearly continuous. Further, it is preferable that the peripheral edge of the embossed concave portion eb is a curved line having no corner, from the viewpoint of touch, but it may have a corner. It is possible to use an embossed pattern in which embossed recesses eb having different shapes are combined as shown in the figure, or the embossed pattern may be formed only with embossed recesses having the same shape.

From the viewpoint of preventing the diffusion of body fluid, the embossed recess eb has a shape extending along a direction not parallel to the longitudinal direction of the product or the width direction as shown in the figure, or It is preferably arranged along parallel directions or provided so as to satisfy both of these shapes and arrangements. In particular, as shown in the drawing, it is preferable that the arrangement directions of the recesses (or the mutual grooves when the recesses extend in a groove shape) intersect. Further, from the viewpoint of preventing diffusion of body fluid, it is preferable that at least one of the following requirements (F) to (G) is satisfied. (F) The mutual distance between the embossed concave portions eb is 5 mm or less, preferably 3 mm or less. (G) The embossed concave portion eb is formed over the cover flap portion F2 in a range of 50% in the product front-rear direction, preferably 70%. (H) The opening width of the embossed recess eb is 0.5 mm or more.

On the other hand, the liquid-impervious back sheet 2 is made of a sheet material having at least water-blocking property such as olefin resin sheet such as polyethylene or polypropylene. It is possible to use a non-woven fabric or a non-woven fabric sheet in which a liquid-proof property is ensured by interposing a waterproof film (in this case, the waterproof film and the non-woven fabric form a liquid-impermeable back sheet). it can. In recent years, from the viewpoint of preventing stuffiness, a material having moisture permeability tends to be used.
The water-impermeable / moisture-permeable sheet material is a microporous sheet obtained by kneading an inorganic filler in an olefin resin such as polyethylene or polypropylene to form a sheet, and then stretching the sheet in a uniaxial or biaxial direction. There is.

As the liquid-permeable top sheet 3, a perforated or non-perforated non-woven fabric, a porous plastic sheet or the like is preferably used. As the material fibers constituting the non-woven fabric, for example, synthetic fibers such as olefins such as polyethylene or polypropylene, polyesters, polyamides, etc., regenerated fibers such as rayon or cupra, natural fibers such as cotton, etc. can be used. A nonwoven fabric obtained by an appropriate processing method such as a lace method, a spun bond method, a thermal bond method, a melt blown method, or a needle punch method can be used. Among these processing methods, the spunlace method is excellent in flexibility and drapability, and the thermal bond method is excellent in bulkiness and softness. Particularly preferred is a porous plastic sheet.

Surface embossing (not shown) can be applied to the liquid-permeable top sheet 3. Further, as shown in FIG. 4, the liquid permeable top sheet 3 is extended to the side of the main body portion, and the skin side surface layer of the flap portions F1 and F2 is formed by this extended portion. It can be omitted. In this case, the embossed recess eb is formed in the laterally extending portion of the liquid-permeable top sheet 3. of course,
Without omitting the side sheet 6, by extending the top sheet 3 on the side sheet 6 or between the side sheet 6 and the back side sheet 3, or by arranging another sheet, the flap portion F1 , F2 may have a three-layer structure (not shown). Further, as can be seen from the above, the flap portions F1 and F2 of the present invention have the number of layers as long as the flap portions F1 and F2 have embossed concave portions on the skin surface side and substantially no irregularities on the rear surface. It is not limited by the material of the layer or layer.

The absorbent core 4 interposed between the liquid impermeable back sheet 2 and the liquid permeable top sheet 3 is made of, for example, fluff pulp and water absorbing polymer. The water-absorbent polymer is mixed in the pulp constituting the absorbent core as, for example, granular powder. As the pulp,
Examples include chemical pulp obtained from wood, cellulose fiber such as dissolving pulp, and artificial cellulose fiber such as rayon and acetate. Softwood pulp having a long fiber length is preferable to hardwood pulp in terms of function and price. Used for.

Further, the liquid-permeable top sheet 3 and the absorbent core 4
An absorption-promoting sheet (not shown) made of a thick hydrophilic non-woven fabric may be disposed between (specifically, the crepe paper 5). It is desirable that the absorption promoting sheet 7 is located at the central portion in the longitudinal direction, extends long on the front side, and is unevenly distributed on the front side. By providing such an absorption promoting sheet, menstrual blood, vaginal discharge, etc. (hereinafter collectively referred to as body fluid) can be quickly absorbed, and the surface in contact with the skin has excellent dry touch property. Will be things.

As shown in the drawing, a crepe paper 5 surrounding the absorbent core 4 is provided so that the crepe paper 5 is interposed between the liquid permeable top sheet 3 and the absorbent core 4. The crepe paper 5 having excellent absorbency quickly diffuses the body fluid and prevents the menstrual blood from returning. In this way, the crepe paper 5
Since it has a function of promptly diffusing body fluid, the absorption promoting sheet can be omitted when this is provided.

On the other hand, in the illustrated embodiment, side rib grooves 8 and 8 are formed by embossing along substantially the longitudinal direction on both sides of the upper surface of the liquid-permeable top sheet 3 straddling the blood discharge corresponding portion. Further, a front groove 10F and a back groove 10F are respectively formed by arc-shaped embosses extending in the width direction so as to connect the front and rear end portions.
Further, a front leakage prevention groove 11 is formed between the front groove 10F and the longitudinal middle portion by an arcuate emboss extending in the width direction. The longitudinal position and the longitudinal middle portion of the front leakage prevention groove 11 are formed. Between the and, side auxiliary grooves 9 and 9 are formed outside the side grooves 8 and 8 by embossing extending along the side grooves 8 and 8, respectively. These groove grooves 8, 9, 10F, 10B, 11 can be formed as so-called heat-sealing embossing by embossing while heating the layers of the relevant part from the use surface side in a stacked state.

These groove grooves 8, 9, 10F, 10B, 1
1 is for preventing menstrual blood from the blood outlet contact portion from spreading outward. These grooves 8, 9, 10
F, 10B, and 11 are not limited to the embossed form as long as they are squeezed at least in the form that the absorbent core 4 is compressed, but the high-pressure squeezed part (high-density part) in the lengthwise direction of the groove.
It is possible to have a form in which the low pressure portions (low density portions) and the low pressure portions alternately appear.

On the other hand, it is also preferable to provide lateral leakage preventing barriers 30, 30 extending in the longitudinal direction of the product on both sides of the absorbent core as shown in the figure. In the embodiment shown in FIG. 3, one end in the width direction of the barrier sheet 31 extending in the longitudinal direction of the product is fixed to the side of the absorbent core 4, the other end is a free end, and elastic expansion / contraction is performed on the free end side portion. Material is 32,3
2 is fixed under extension along the longitudinal direction. The front and rear ends of the barrier sheet 31 in the longitudinal direction of the product are joined to each other in a folded state, and not joined at an intermediate portion. Thus, in the use state, as shown in FIG. 3, the intermediate portions of the barrier sheets 31, 31 are erected by the contracting force of the elastic expansion / contraction members 32, 32, and function as menstrual blood lateral leakage prevention barriers 30, 30.

The side leakage prevention barriers 30 and 30 are
As shown in FIG. 5, the inner portions of the side sheets 6 and 6 extend inward from the side edges of the absorbent core 4, and the extended portions 6
It can also be formed by replacing e and 6e with the barrier sheets 31 and 31. As can be seen from this case as well, due to the manufacturing method and the like, the side leakage prevention barrier 3
0 and 30 may have embossed recesses.

<Example> A side sheet material made of an air-through nonwoven fabric having a basis weight of 25 g / m ² and a basis weight of 23 g / m ²
And a liquid-impermeable back sheet material made of the polyethylene film described above were prepared and bonded to each other to prepare samples of Example 1, Comparative Example 1 and Comparative Example 2 below. For each sample, bending rigidity B and resilience 2HB (bending hysteresis width) were measured using a pure bending tester manufactured by Kato Tech.
Was measured. Further, the unevenness of the non-bonded surface of the liquid-impermeable back sheet material was visually evaluated. The results are shown in Table 1. In addition,
Bending stiffness B means that the larger the value, the stronger the stiffness,
The resilience 2HB means that the larger the value, the higher the resilience. Example 1-side sheet material described above (A) ~
After embossing which satisfies all of (D), this is laminated with a liquid impermeable back sheet material. Comparative Example 1 ... Both the side sheet material and the liquid impermeable back sheet material are laminated without embossing. Comparative Example 2 A sheet obtained by laminating a side sheet material and a liquid-impermeable back sheet material, and then subjecting the laminated sheet to the same embossing as in Example 1.

[0035]

[Table 1]

[0036]

As described above, according to the present invention, an absorbent article having a flap portion in which the pressure-sensitive adhesive does not easily transfer to the shorts can be adopted while the body fluid diffusion suppressing form by the embossed recess can be adopted. Further, when the elasticity of the flap portion is adjusted according to the embossing characteristics and processing form, it is difficult for the wearer to feel a sense of discomfort due to friction with the flap portion, or to cause a rash on the portion rubbing against the flap portion.

[Brief description of drawings]

FIG. 1 is a plan view (side surface for absorbing body fluid) of a sanitary napkin according to the present invention in a developed state.

FIG. 2 is a bottom view (back surface or exterior surface) of the sanitary napkin according to the present invention in a developed state.

3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a sectional view showing another embodiment.

FIG. 5 is a cross-sectional view showing another form.

[Explanation of symbols]

1 ... Sanitary napkin, 2 ... Liquid impermeable back sheet, 3 ... Liquid permeable top sheet, 4 ... Absorption core, 5 ... Crepe paper, 6
... side seats, F1 ... folded flaps, F2 ... hip cover flaps, eb ... embossed recesses.

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4C003 DA06 HA05                 4C098 AA09 CC07 CC37 CE14 DD25                       DD30

Claims (6)

[Claims] 1. An absorbent article having a body part having a body fluid absorbing part and a flap part provided around the body part, wherein at least the flap part has an embossed concave portion on a skin surface side surface and a back surface thereof. The absorbent article is characterized in that it has substantially no unevenness, and an adhesive layer is provided on the back surface of this flap portion. 2. The absorbent article according to claim 1, wherein an area ratio of the embossed concave portion to the flap portion is 5 to 80%. 3. The absorbent article according to claim 1, wherein the embossed recesses have a depth of 0.01 mm or more. 4. The flap portion is formed by laminating a non-woven fabric and a polyethylene sheet, and has an average bending rigidity of 0.03 to 0.10 gcm ² / cm.
The absorbent article according to any one of claims 1 to 3. 5. The absorbent article according to claim 1, wherein the embossed recess has an opening width of 0.7 mm or more. 6. The absorbent article according to claim 1, wherein a large number of the embossed concave portions are formed in the plane direction of the flap portion with different number densities.