JP4346165B2 - Absorbent articles - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an absorbent article such as a sanitary napkin that is excellent in deodorizing performance of bad odor and excellent in appearance.
[0002]
[Prior art and problems to be solved by the invention]
Conventionally, in absorbent articles such as sanitary napkins, disposable diapers, and incontinence pads, there is a technique for containing activated carbon in an absorbent that absorbs and retains body fluids in order to prevent the generation of malodor from body fluids such as menstrual blood and urine. Are known.
However, in the conventional absorbent article, since the color of the activated carbon appears on the appearance of the article, the appearance is poor and the user may feel uncomfortable. In addition, although reducing the usage-amount of activated carbon is considered, it becomes difficult to provide the absorbent article excellent in deodorizing performance at low cost.
[0003]
Accordingly, an object of the present invention is to provide an absorbent article that is excellent in performance for deodorizing malodors generated by menstrual blood, urine, and the like, and has a good appearance.
[0004]
[Means for Solving the Problems]
The present invention relates to an absorbent article having a liquid-permeable surface layer, a liquid-impermeable leak-proof layer and a liquid-retaining absorbent layer interposed between the two layers, wherein the absorbent layer contains activated carbon. A liquid-permeable hiding layer is disposed between the surface layer and the absorbent layer, and the L value measured from the surface layer side of the absorbent article is at least greater than the L value of the absorbent layer. The above object is achieved by providing an absorbent article that is 5 points or more larger.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described based on preferred embodiments with reference to the drawings. As shown in FIGS. 1 and 2, a sanitary napkin 1 as an absorbent article has a substantially vertically long shape, a surface sheet 2 as a liquid-permeable surface layer, and a liquid-impermeable leak-proofing. It has a back sheet 3 as a layer and an absorbent body 4 as a liquid-retaining absorbent layer interposed between both layers.
[0006]
As shown in FIG. 1, the absorber 4 has a rectangular shape in plan view. The top sheet 2 and the back sheet 3 are both larger in outer dimensions than the absorbent body 4, the top sheet 2 is arranged so as to cover the skin contact surface side of the absorbent body 4, and the back sheet 3 is the non-skin of the absorbent body 4. It arrange | positions so that the contact surface side may be covered, and it is mutually heat-seal | fused and joined in the part extended outward rather than the outer peripheral edge part of the absorber 4. FIG.
[0007]
Thus, the absorber 4 contains activated carbon 41. Further, a concealment sheet 5 as a liquid-permeable concealment layer is disposed between the top sheet 2 and the absorber 4.
The concealment sheet 5 has a function of preventing the color (black) of the activated carbon 41 contained in the absorbent body 4 from being seen through from the skin contact surface side or reducing the visible level. Thus, it is arranged on the non-skin contact surface side of the topsheet 2 so as to cover the entire surface of the absorbent body 4 on the skin contact surface side.
[0008]
And L value (henceforth skin contact surface L value) which measured the sanitary napkin 1 from the surface sheet 2 side is at least 5 points or more larger than L value (henceforth an absorber L value) of the absorber 4. .
[0009]
Here, the absorber L value and the skin contact surface L value are measured as follows.
Absorber L value: Obtained by measuring L value of Hunter Lab color system using spectrocalorimeter (color difference meter, type “SX-Σ80”) manufactured by Nippon Denshoku Industries Co., Ltd. The measurement was performed on the surface of the absorbent body 4 on the surface sheet 2 side.
Skin contact surface L value: obtained by measuring the L value of the Hunter Lab color system from the surface sheet 2 side using the same apparatus as the measurement of the absorber L value. It should be noted that the L value was used as a scale in which the darker color of the activated carbon was difficult to see because the larger (higher) value appeared relatively white. Moreover, about the presence or absence of the structural member distribute | arranged to the non-skin contact surface side of the absorber 4, such as the back surface sheet 3 and the adhesive agent 6 for slip prevention, the measurement of the absorber L value and the skin contact surface L value Unify the conditions with measurement.
[0010]
When the skin contact surface L value is 5 points or more larger than the absorbent body L value, the degree of black-gray appearing by the activated carbon 41 of the absorbent body 4 from the skin contact surface side of the topsheet 2 is sufficiently small. The napkin does not look good or looks very good. On the other hand, when the skin contact surface L value is larger than the absorber L value, but the difference is less than 5 points or more, the extent to which the activated carbon 41 of the absorber 4 can be seen is large, and the appearance is poor. It is easy to feel anxiety and filth.
[0011]
The condition that the skin contact surface L value is 5 points or more, preferably 10 to 20 points larger than the absorber L value (hereinafter referred to as black concealment conditions), impairs excellent absorption performance and excellent deodorization performance. From the viewpoint of satisfying without making it, the absorber L value is preferably 65 to 85, and the skin contact surface L value is preferably 85 to 95.
[0012]
Hereinafter, the preferable structure of the sanitary napkin 1 of this embodiment is further demonstrated. The concealment sheet 5 has a liquid passing speed of 30 seconds or less, particularly 10 to 20 seconds, from the viewpoint of giving excellent absorption performance to the sanitary napkin 1 and effectively concealing the black color of the activated carbon 41. preferable.
Here, the liquid passing speed of the masking sheet (masking layer) 5 is measured by the method shown below.
That is, an aqueous glycerin solution adjusted to 85 wt% is prepared, and the concealment sheet is sandwiched between a pair of cylindrical glassware having an inner diameter of 35 mm, and the concealment sheet is fixed horizontally. Then, 10 g of the glycerin aqueous solution is poured into the upper glass apparatus. The time from the start of the injection of the glycerin aqueous solution until the entire amount passed through the concealment sheet was measured, and the time required for this passage was defined as the liquid passing speed (seconds). Note that the time when the entire amount passed was the time when the liquid disappeared from the upper surface of the sheet, and it was determined that the entire amount did not pass yet when the liquid was in the interlayer.
[0013]
Examples of the material for forming the concealment sheet 5 include a nonwoven fabric, paper, a perforated sheet, and the like. From the viewpoint of providing the sanitary napkin 1 with excellent absorption performance and effectively concealing the black color of the activated carbon 41, A melt blown nonwoven fabric or a composite sheet of a perforated sheet and a nonwoven fabric is preferred, and the basis weight thereof is preferably ^{2 to} 50 g / m ² , particularly preferably 5 to 30 g / m ² .
[0014]
From the same viewpoint, the concealment sheet 5 preferably contains a filler. The filler to be contained in the concealment sheet 5 is preferably a white inorganic substance, particularly preferably titanium oxide, calcium carbonate, kaolin, or talc. In this case, the filler content is 0.1 to 80 weight in the concealment sheet 5. %, Particularly 1 to 5% by weight is preferred. Moreover, it is preferable that a filler exists in the planar direction and thickness direction of the concealment sheet 5 being dispersed.
[0015]
The concealment sheet 5 in the disposable diaper 1 is substantially integrated with the absorber 4 via an adhesive (not shown) applied to the lower surface. Here, the fact that the concealment sheet 5 is “substantially integrated” with the absorber 4 means that there is no gap between at least a part of the concealment sheet and the absorber using physical or chemical means. Means that. The same applies to the case where the concealment sheet 5 is substantially integrated with the top sheet 2.
As described above, the concealment sheet 5 is substantially integrated with the top sheet 2 and / or the absorber 4 so that menstrual blood, urine, etc. can be quickly and efficiently transmitted to the absorber, and sufficient deodorizing ability can be obtained. Can be expressed.
[0016]
As the surface sheet 2, those normally used in absorbent articles such as sanitary napkins can be used. However, the viewpoint of giving excellent absorbent performance to the sanitary napkin 1 and the viewpoint of effectively concealing the black color of the activated carbon 41. Therefore, the surface sheet 2 has a liquid flow rate measured in the same manner as the liquid flow rate of the concealment sheet 5 is preferably 30 seconds or less, particularly preferably 10 to 20 seconds. Moreover, the forming material of the surface sheet 2 is preferably a perforated sheet or a nonwoven fabric, and the basis weight thereof is preferably 5 to 30 g / m ² .
[0017]
Moreover, it is preferable that the liquid flow rate measured by said method by superimposing the surface sheet 2 and the concealment sheet 5 is 60 seconds or less, and especially 10 to 30 seconds.
[0018]
The absorbent body 4 is activated carbon 41 in the absorbent body 4 from the viewpoint of suppressing the absorbent body L value so that the above black concealment condition can be easily satisfied and providing the sanitary napkin 1 with excellent deodorizing performance. Is preferably 5 to 80% by weight, more preferably 10 to 50% by weight. Moreover, the basis weight (dispersion basis weight) of the activated carbon 41 is preferably ³ to 500 g / m ² , particularly preferably ²⁰ to 100 g / m ² .
[0019]
As shown in FIG. 2, the absorbent body 4 in the sanitary napkin 1 of the present embodiment contains activated carbon 41 and a water-absorbing polymer 42. Specifically, in the interfiber gap of the fiber web 43, It consists of activated carbon 41, a water-absorbing polymer 42 and a sheet-like absorbent sheet that is held. In the absorber 4, the activated carbon 41 is fixed to the fibers constituting the fiber web 43 through the water-absorbing polymer 42, and the activated carbon 41 and the polymer 42 are mixed in the sheet-like absorber 4. Further, the absorbent body 4 spreads the water-absorbing polymer 42 on the wet lower fiber web, and spreads the activated carbon 41 at the same time as or before and after the spraying, and superimposes the dried upper fiber web on it. It is obtained by integrating the upper and lower layer fiber webs by drying, and the surface of the fiber web 43 in the absorbent body 4 does not substantially contain either the activated carbon 41 or the polymer 42.
[0020]
As for the weight ratio of the activated carbon 41 and the water-absorbing polymer 42, the former / latter ratio is preferably 1/10 to 10/1, particularly 1/3 to 3/1.
[0021]
As the activated carbon 41, various activated carbons conventionally used for deodorization can be used, and it is particulate activated carbon and contains 90% or more of particles having a particle size of 50 to 500 μm, particularly 150 to 400 μm. Those are preferred.
[0022]
As the water-absorbing polymer 42, various conventionally known polymers can be used, and those capable of absorbing and holding a liquid 20 times or more of its own weight and capable of gelling are preferable. Preferable examples of the water-absorbing polymer 42 include polyacrylic acid and a salt thereof, and a polyacrylate graft polymer such as starch, crosslinked carboxylmethylated cellulose, a polymer or copolymer of acrylic acid or an alkali metal acrylate, and the like. Can be mentioned.
[0023]
As a fiber which comprises the fiber web 43, cellulosic fibers, such as natural celluloses, such as a wood pulp and cotton, and regenerated celluloses, such as rayon and a cupra, can be used, for example. Also, filaments of thermoplastic fibers, staple fibers, etc. can be used. The fiber web means a sheet-like material formed by mechanical entanglement of fibers, adhesion or fusion between fibers, and examples thereof include paper, non-woven fabric, and composites thereof.
[0024]
As a constituent fiber in the case of using a fiber sheet such as a nonwoven fabric as the top sheet 2, various fibers conventionally used for a top sheet of an absorbent article can be exemplified. Moreover, as a constituent fiber when using fiber sheets, such as a nonwoven fabric and paper, as the concealment sheet 5, the various fiber conventionally used for the surface sheet and absorber of an absorbent article can be mentioned. The concealment sheet 5 may be made of the same material as the top sheet 2, but is preferably made of a forming material different from the top sheet 2.
As the material for forming the back sheet 3, those usually used in absorbent articles such as sanitary napkins can be used without particular limitation.
[0025]
A release paper 7 is adhered to the skin contact surface side of the back sheet 3 of the sanitary napkin 1 via an adhesive 6, and the sanitary napkin 1 is peeled off the release paper 7 and adhered to shorts. Used in the same manner as a conventional sanitary napkin.
[0026]
The concealment sheet 5 may be integrated with the surface sheet 2 by being joined to the surface sheet 2 by an adhesive, heat sealing, or the like. Further, the absorbent body 4 may be an absorbent body formed by wrapping a mixture of fluff pulp and superabsorbent polymer with absorbent paper. Moreover, the surface sheet 2 and the concealment sheet 5 may each be a laminated sheet composed of two or more layers.
In addition to sanitary napkins, the present invention is applicable to absorbent articles such as disposable diapers, incontinence pads, breast milk pads, panty liners, and pet sheets.
[0027]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, absorbent articles, such as a sanitary napkin which is excellent in the deodorizing performance of the malodor generated from the absorbed liquid and looks good, can be provided. In addition, since the absorbent article of this invention uses activated carbon as a deodorizer, it is excellent in the deodorizing performance with respect to various malodorous substances, and can be manufactured comparatively cheaply.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a sanitary napkin as an embodiment of an absorbent article of the present invention.
FIG. 2 is a cross-sectional view taken along line XX of FIG.
[Explanation of symbols]
1 Absorbent article (Sanitary napkin)
2 Top sheet 3 Back sheet 4 Absorber 41 Activated carbon 42 Water-absorbing polymer 5 Concealment sheet

Claims (3)

In an absorbent article having a liquid-permeable surface layer, a liquid-impermeable leak-proof layer, and a liquid-retaining absorbent layer interposed between both layers,
The absorbing layer contains particulate activated carbon containing 90% or more of particles having a particle size of 50 to 500 μm ,
A liquid-permeable hiding layer is disposed between the surface layer and the absorbing layer,
The L value measured from the surface layer side of the absorbent article is at least 5 points greater than the L value of the absorbent layer,
The concealing layer contains a filler, and the filler is made of a white inorganic material selected from titanium oxide, calcium carbonate, kaolin and talc, and the content of the filler is 1 to 5 % by weight in the concealing layer. And the filler is dispersed in the planar direction and the thickness direction of the concealing layer ,
The absorbent layer has a configuration in which the activated carbon and the water-absorbing polymer are held on a fiber web, and both the activated carbon and the water-absorbing polymer are substantially formed on the surface of the fiber web on the side of the concealment layer. Not included in the
The activated carbon has a content of 10 to 50% by weight in the absorbent layer and a basis weight in the absorbent layer of 20 to 100 g / m ² .
The absorbent article whose weight ratio of the said activated carbon in the said absorption layer and the said water absorbing polymer is 1/3-3/1 .   The absorbent article according to claim 1, wherein a liquid passing rate of the concealing layer is 30 seconds or less. The absorbent article according to claim 1 or 2 , wherein the concealing layer is substantially integrated with the surface layer and / or the absorbent layer.

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