JP3737335B2 - Absorbent articles - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an absorbent article, and more particularly to an absorbent article that is particularly suitably used as a sanitary napkin, a cage sheet, a disposable diaper, or the like.
[0002]
[Prior art and problems to be solved by the invention]
It is known that functional materials having various functions such as a deodorizing function, an antibacterial function, and a thermal function are included in absorbent articles such as sanitary napkins and disposable diapers to impart various functions to the absorbent articles. Yes. Most of the functional materials are colored such as black, brown, and yellow. Therefore, when such a colored functional material is contained in the absorbent article, there is a problem in appearance because it tends to give the user a negative impression that it is not hygienic or looks out of date.
[0003]
Therefore, an object of the present invention is to provide an absorbent article having a good appearance impression.
Another object of the present invention is to provide an absorbent article having a high concealability of a colored functional material.
Furthermore, the present invention is to provide an absorbent article that can prevent the functional material from falling off.
[0004]
[Means for Solving the Problems]
The present invention relates to an absorbent article having a liquid-permeable surface layer, a liquid-impermeable back layer, and a liquid-retaining absorbent layer interposed between both layers.
The absorbing layer is, and including absorber functional material colored to impart predetermined functions to the absorbent article has a color layer positioned on the upper surface or the lower surface of the absorbent portion,
The colored layer has a predetermined color so as to reduce the color of the functional material and to make the color of the colored layer visible when the absorbent article is viewed from the surface layer side or the back surface layer side. The above-mentioned object is achieved by providing an absorbent article that is colored.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described below based on preferred embodiments with reference to the drawings. FIG. 1 is a partially broken perspective view of a sanitary napkin according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line II-II of an absorbent body in the sanitary napkin shown in FIG. FIG. 3 is a cross-sectional view taken along the line III-III of the absorbent body in the sanitary napkin shown in FIG.
[0006]
A sanitary napkin 1 shown in FIGS. 1 and 2 has a vertically long shape, a top sheet 2 constituting a liquid-permeable surface layer, a back sheet 3 and a top sheet constituting a liquid-impermeable back layer. 2 and an absorbent body 4 as a liquid retaining absorbent layer interposed between the back sheet 3 and the back sheet 3. The top sheet 2 and the back sheet 3 extend outward from the peripheral edge of the absorber 4, and the sheets 2 and 3 are joined by a predetermined joining means in the extended portion to sandwich the absorber 4. Yes.
[0007]
An adhesive layer (not shown) for fixing the napkin 1 to the wearer's clothes is formed on the outer surface of the back sheet 3. This pressure-sensitive adhesive layer is covered with a release paper (not shown), and is protected until the napkin 1 is used. As the top sheet 2, various nonwoven fabrics, perforated materials, perforated films, and the like are used. In the present embodiment, perforated nonwoven fabrics are used. As the back sheet, a film made of a thermoplastic resin and having or not having moisture permeability is used. Moreover, as an adhesive layer and a release paper, the thing similar to what is used for the conventional napkin can be used.
[0008]
As shown in FIG. 2, the absorbent body 4 is colored to cover the entire upper and lower surfaces of the absorbent sheet 4a as an absorbent section that is folded in three in a C shape so that the left and right sides overlap each other. And a colored sheet 4b as a layer. Similar to the absorbent sheet 4a, the colored sheet 4b is also folded in three in a C shape so that the left and right sides overlap. As shown in FIG. 3, the front and rear ends of the absorbent sheet 4a are sealed by joining the opposing colored sheets 4b together in a bag shape by a predetermined joining means. Thus, the absorption sheet 4a is entirely covered with the colored sheet 4b, and there is no portion exposed to the outside.
[0009]
Between the absorber 4 and the top sheet 2, a shielding sheet 5 as an intermediate layer is disposed so as to cover the entire upper surface of the absorber 4.
[0010]
Thus, in the napkin 1 of the present embodiment, the absorbent sheet 4a in the absorbent body 4 contains fiber material, superabsorbent polymer particles and functional material particles. The absorbent sheet 4a is configured such that the particles of the superabsorbent polymer and the particles of the functional material are dispersed and arranged in a three-dimensional manner between the fiber materials in the sheet made of the fiber material. More specifically, the functional material particles are bonded and fixed to the fiber material via the superabsorbent polymer particles. This effectively prevents the superabsorbent polymer particles and the functional material particles from falling off. The absorbent sheet 4a having such a structure is described in detail, for example, on page 3 line 5 to page 6 line 12 of International Publication WO 00/04938 relating to the previous application of the present applicant.
[0011]
The functional material imparts a predetermined function to the napkin 1. Examples of the function include a deodorizing / deodorizing function, an antibacterial function, an aroma function, a water absorption retention function, a heat function, and the like, and an appropriate functional material is used according to the required performance of the napkin 1.
[0012]
The functional material has a color such as black, brown, or yellow. In this specification, “colored” means a color other than white, and includes both chromatic and achromatic colors. Examples of the functional material exhibiting such a color include, but are not limited to, black activated carbon particles used for deodorization and deodorization, black or brown iron powder used for heat, and the like. . In the present embodiment, black activated carbon particles are used as the functional material, and the activated carbon particles give the absorbent sheet 4a an appearance in which black spots are scattered on a white background.
[0013]
The colored sheet 4b covering the upper and lower surfaces of the absorbent sheet 4a is colored in a predetermined color, which is different from the color of the functional material in the present embodiment. The meaning of the color is as described above. Therefore, in order to increase the hiding property in the conventional absorbent article, for example, a white colorant such as titanium oxide is added to the backsheet to make it white turbid. It is not included in the concept. Further, the absorbent sheet 4b is colored to such an extent that when the napkin 1 is viewed from the top sheet 2 side or the back sheet 3 side, the color of the functional material is reduced and the color of the colored sheet 4b is visible. ing. As described above, since the absorbent sheet 4a has an appearance in which black spots are scattered on a white background, when the absorbent body 4 is configured only by this, the black spots are seen through when the napkin 1 is viewed from the top sheet 2 side. Although this may cause a decrease in the appearance of the napkin 1, the use of the colored sheet 4 b colored to the extent described above hides the black spots and reduces the color caused by the black spots. impression reduction is prevented appearance. Further, depending on the coloring method, a pattern is formed, design properties are imparted to the napkin 1, and added value is added. In addition, in the present embodiment, as described above, the absorbent sheet 4a is entirely covered with the colored sheet 4b, and there is no portion exposed to the outside. The dropping of the superabsorbent polymer particles and the functional material particles is more effectively prevented.
[0014]
The colored sheet 4b is, in the Lab-based color system, L = 20 to 80, particularly 30 to 60, a = -50 to 50, particularly -40 to 10, b = -50 to 50, particularly -40 to 10, It is preferable that ΔE (H) = 20 to 80, particularly 30 to 50. These values are obtained by using a color difference meter SZ-Σ80 (trade name) manufactured by Nippon Denshoku Industries Co., Ltd., reflection 1, measurement diameter 30 mmφ, light source C / 2, black pressing plate Lab = (6, 0, 0) Measured at conditions.
[0015]
The colored sheet 4b is made of paper, a pulp sheet, and a nonwoven fabric made of a fiber material, and the colored material 4b has a predetermined color because the fiber material is colored. Examples of the fiber material include natural fibers or recycled fibers having a hydrophilic surface such as pulp, rayon, and cotton, and synthetic fibers such as polyethylene, polypropylene, polyester, and polyamide. When the fiber material is a hydrophilic natural fiber or regenerated fiber, the fiber material can be colored by adsorbing a colorant such as a dye on the surface of the fiber material. On the other hand, when the fiber material is a synthetic fiber, a master batch of a colorant composed of a pigment or the like is previously kneaded into the resin constituting the synthetic fiber, and the fiber material is colored by spinning the fiber from the resin. can do. Moreover, when using a core-sheath type synthetic fiber, it is preferable to color a core part.
[0016]
In order to form the colored sheet 4b from the fiber material, for example, a wet papermaking method, a dry papermaking method, and various nonwoven fabric manufacturing methods such as a spunbond method, a spunlace method, and a heat bond method can be used. In particular, when a non-woven fabric is used as the colored sheet 4b, it is preferably a non-woven fabric formed by a heat bond method using a core-sheath type fiber having a colored core portion. When the colored sheet thus obtained is not hydrophilic or has a low degree of hydrophilicity, it is preferable to perform a predetermined hydrophilic treatment.
[0017]
The shielding sheet 5 is made of a material such as paper, pulp sheet, and nonwoven fabric, and has liquid permeability. When the material is not hydrophilic or has a low degree of hydrophilicity, it is preferable to perform a predetermined hydrophilization treatment. Further, the shielding sheet 5 is white or colorless, and has a light transmittance that allows the color of the absorber 4, that is, the color of the colored sheet 4 b to be visible when the napkin 1 is viewed from the top sheet 2 side. Yes. When the shielding sheet 5 is not arranged, the color of the absorber 4 is visually recognized through the top sheet 2 having a relatively high light transmittance, and in some cases gives a terrible impression to the user. This is especially true when the color of the absorbent body 4 is directly visible through the perforations formed in the top sheet, as in this embodiment. On the other hand, by using the shielding sheet 5, the hue of the absorber 4 is relaxed, and a soft pastel tone is given to the user. Further, there are cases where it is difficult to finely adjust the hue when coloring the absorber 4, but the adjustment is facilitated by using the shielding sheet 5.
[0018]
The degree of color permeability of the shielding sheet 5 is measured through the top sheet 2 of the napkin 1 when the color of the absorber 4 is L = 5-50, a = -50-50, b = -50-50. The color of the absorber 4 is L = 50 to 95, a = −20 to 20, b = −20 to 20, particularly L = 70 to 95, a = −10 to 10, and b = −10 to 10 , ΔE (H) = 5 to 20, and preferably 7 to 15.
[0019]
The shielding sheet 5 preferably has a bulk softness of 3 to 100 cN, particularly 5 to 30 cN, from the viewpoint of preventing the fit of the napkin 1 and deterioration of the texture due to excessively high rigidity of the napkin 1. . Bulk softness is measured by the following method.
[0020]
<Measurement method for bulk softness>
The shielding sheet 5 is cut out in a rectangular shape so that the length in the length direction corresponding to the longitudinal direction of the napkin 1 is 140 mm and the length in the width direction is 30 mm (for convenience of measurement, the longitudinal front and rear end portions May be semi-circular or trapezoidal). The cut-out rectangular shielding sheet 5 is made into a cylinder (the overlapping portion at both ends is about 5 mm) so that the length direction is the circumferential direction, and the overlapping portion is a staple [No. 10 manufactured by Max Co., Ltd. -1M needle] is used to fasten two places at intervals of 10 mm to obtain a cylindrical measurement sample having a height of 30 mm. The obtained measurement sample is set in a Tensilon compression tester (manufactured by Toyo Baldwin Co., Ltd., “RTM-25”), and compressed by a compression plate in the axial direction of the cylinder at a compression speed of 10 mm / min. The initial position of the compression plate is about 32 mm, which is slightly wider than the initial sample width. The sample is compressed to a position where the measurement sample width (height) is 15 mm, and the average value (n = 3) of the maximum stress values is set as the bulk softness value.
[0021]
The back sheet 3 in the napkin 1 of the present embodiment is colored in the color of the absorber 4, that is, the color having substantially the same hue as the color of the colored sheet 4 b. Thereby, the absorber 4 and the back sheet 3 are harmonized, and the appearance impression when the napkin 1 is viewed from the top sheet 2 side is further improved. Moreover, the shielding effect of the said functional material when the napkin 1 is seen from the back seat | sheet 3 side also arises.
[0022]
The degree of coloring of the backsheet 3 is such that the value of ΔE (H) with the colored sheet 4b is 0 to 35, particularly 5 to 20, from the point that the appearance impression of the napkin 1 is further improved. preferable.
[0023]
The present invention is not limited to the embodiment. For example, in the above-described embodiment, the upper and lower surfaces of the absorbent sheet 4a are covered with the colored sheet 4b. However, only the upper surface of the upper and lower surfaces of the absorbent sheet 4a may be covered with the colored sheet 4b. Only may be coated. Covering the upper surface of the absorbent sheet 4a with the colored sheet 4b is effective in that the impression to the user is improved when the absorbent article of the present invention is applied to sanitary napkins and origami sheets, and the absorbent sheet 4a. Covering the lower surface with the colored sheet 4b is effective when the absorbent article of the present invention is applied to a disposable diaper or an incontinence pad.
[0024]
Moreover, in the said embodiment, although each whole surface of the upper and lower surfaces of the absorption sheet 4a was coat | covered with the colored sheet 4b, each surface may be coat | covered only with the colored sheet 4b.
[0026]
Moreover, in the said embodiment, although the back sheet 3 was colored in the color of the substantially same hue as the color of the absorber 4, the back sheet 3 does not need to be colored.
[0027]
Moreover, the absorbent article of the present invention is not limited to sanitary napkins, but can also be applied to vaginal sheets, disposable diapers, incontinence pads, and the like.
[0028]
【The invention's effect】
According to the absorbent article of the present invention, the color of the colored functional material contained in the absorber is concealed, and the appearance impression is improved. In particular, the functional material is effectively prevented from falling off by covering the functional material with a colored sheet.
[Brief description of the drawings]
FIG. 1 is a partially broken perspective view of a sanitary napkin according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view taken along the line II-II of the absorbent body in the sanitary napkin shown in FIG.
3 is a cross-sectional view taken along the line III-III of the absorbent body in the sanitary napkin shown in FIG.
[Explanation of symbols]
1 Sanitary napkin (absorbent article)
2 Top sheet 3 Back sheet 4 Absorber 4a Absorbent sheet 4b Colored sheet 5 Shielding sheet

Claims (5)

In an absorbent article (1) having a liquid-permeable surface layer (2) , a liquid-impermeable back layer (3) and a liquid-retaining absorbent layer (4) interposed between both layers,
The absorbing layer (4), wherein including absorber functional material colored to impart predetermined functions to the absorbent article (1) and (4a), located on the upper surface or the lower surface of the absorbent portion (4a) A colored layer (4b) ,
The colored layer (4b) has a color that reduces the color of the functional material when the absorbent article (1) is viewed from the surface layer side or the back layer side, and the color of the colored layer (4b) . Absorbent article colored in a predetermined color to such an extent that can be visually recognized. The absorptive article according to claim 1 in which said back layer (3) is colored in the color of the same hue as the color of said colored layer (4b). The absorbent article according to claim 2, wherein the back layer (3) is colored so that a value of ΔE (H) with the colored layer (4b) is 0 to 35. The colored layer (4b) is colored so that L = 20 to 80, a = −50 to 50, b = −50 to 50, ΔE (H) = 20 to 80 in the Lab color system. The absorbent article according to any one of claims 1 to 3. The absorbent article according to any one of claims 1 to 4, wherein the absorbent part (4a) is entirely covered with a colored layer (4b).

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