JP2009254597A - Absorbent article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an absorbent article which easily visually recognizes color changes of an indicator by contact with moisture included in urine or the like and maintains excellent moisture permeability of the absorbent article. <P>SOLUTION: An absorbent article 10 has an absorber 3 and a back sheet 1 placed outside the absorber 3 and an indicator 13 whose color changes by contact with moisture is placed between the absorber 3 and the back sheet 1. The back sheet 1 has a moisture permeable sheet 11 on the side of the absorber and an exterior sheet 12 on the outside, the moisture permeable sheet 11 is colored yellow by color agent contained in the moisture permeable sheet 11, light transmission rate of the colored moisture permeable sheet is 30% or larger, and the moisture permeability in the moisture permeable sheet is 2.0g/100 cm<SP>2</SP>*h or larger. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an absorbent article for visually informing that urination has occurred.

  Various proposals have been made that have a function of visually informing the wearer and / or its guardian that the absorbent body absorbs and retains urine, menstrual blood, etc., when the absorbent article is worn. . For example, a disposable napkin having a black appearance and a white absorber or the like partially visible has been proposed (see Patent Document 1). Thereby, when it wears in combination with black underwear, the napkin is not conspicuous. On the other hand, if there is excretion of menstrual blood or the like, the absorber or the like is discolored, and the wearer can visually know that.

  Unlike the above, there are some that use a specific agent or a pH indicator that changes color when contacted with moisture by urination or the like as an indicator. Among them, a combination of a character design that does not change color and a design that changes color has been proposed as a method that focuses on visual effects, and is said to be effective for children's excretion training (see Patent Document 2). In addition, for the purpose of improving visibility, there is one in which the light transmittance of the back sheet disposed outside the indicator that makes it possible to visually recognize that the absorber is in a wet state is in a predetermined range (see Patent Document 3). . Furthermore, the back sheet or the surface of the back sheet has been proposed in which the above color change indicator and a colored layer that does not change color are provided by printing or the like (see Patent Document 4).

Japanese translation of PCT publication No. 2004-520856 Special table 2003-501209 gazette Special table 2007-117649 JP 2004-337385 A

  In the absorbent article using the variable color indicator described above, the indicator is usually disposed at a position in contact with the absorber, and the back sheet is disposed on the outside thereof. Therefore, from the outside of the absorbent article, the color change of the indicator must be seen through the back sheet, and is difficult to visually recognize. Further, when the agent for changing color used for the indicator comes into contact with urine or the like, blurring may occur or the color or outline may be blurred. Further, if the visibility is emphasized and the indicator is made to have a conspicuous color, the cleanliness of the absorbent article that is usually used on the skin may be impaired. In this way, the wearer or guardian accurately confirms that there was urination visually even when the color is clean and visible through the back sheet, and in some cases bleeds. Notifying is not easy. On the other hand, leaving urination etc. for a long time will not only cause discomfort, but it may also cause rough skin and rash in infants, etc. Need to know).

  In addition, if colored printing is performed on the back sheet, the original function required for the back sheet may be affected. In particular, since the portion where the indicator is disposed is damp, it is required to have high moisture permeability and prevent stuffiness. For this reason, a back sheet having a high moisture permeability has been developed and suitably used. However, when colored printing is performed on the back sheet, the hygroscopicity of the fibers on the back sheet surface is hindered by the printed film, and in some cases, even fine pores in the sheet exhibiting moisture permeability are blocked, and the original good permeability is obtained. It will also reduce the wetness.

  An object of the present invention is to provide an absorbent article that can easily visually recognize discoloration of an indicator due to contact with moisture contained in urine or the like and that has good moisture permeability. In particular, with regard to the visibility of the indicator, it was intended to provide an absorbent article that clearly notices that there was urination, etc. by making the indicator clearly visible after the discoloration of the indicator in the initial wear, with a conspicuous and clean appearance. To do. Furthermore, an object of the present invention is to provide an absorbent article that has the above-described excellent performance and can be manufactured efficiently and at low cost without requiring a complicated process.

An object of the present invention is to provide an absorptivity having an absorber and a back sheet disposed outside the absorber, and an indicator that changes color by contact with moisture between the absorber and the back sheet. The backsheet has a moisture permeable sheet on the absorber side and an exterior sheet on the outer side, and the moisture permeable sheet is colored yellow by a colorant contained in the moisture permeable sheet. The light-transmitting material of the colored moisture-permeable sheet is 30% or more, and the moisture-permeable sheet has a moisture permeability of 2.0 g / 100 cm ² · h or more.

  The absorbent article of the present invention has a colored region that makes it easy to visually recognize the indicator when it changes color due to contact with moisture contained in urine or the like, and also exhibits good moisture permeability. In particular, regarding the visibility of the indicator of the absorbent article of the present invention, after the indicator was discolored with a conspicuous and clean appearance at the beginning of wearing, this was clearly recognized visually to confirm that there was urination, etc. It has an excellent effect of being able to be notified. Furthermore, the absorbent article of the present invention can be produced efficiently and at low cost without requiring a complicated process, while having the above-described excellent performance.

The present invention will be described in detail based on preferred embodiments with reference to the drawings.
FIG. 1 is a perspective view schematically showing a shape when a pants-type disposable diaper as a preferred embodiment of the absorbent article of the present invention is mounted. In the diaper 10 of the present embodiment, a waist opening t and a pair of left and right leg openings s are provided. The waist opening t is passed through the waist and waist of the wearer, and the leg opening s is passed through the thigh. Is done. A plurality of elastic members 6 forming waist gathers are disposed in the vicinity of the waist opening t, so that the waist circumference and waist circumference of the wearer are appropriately tightened to fit. Also, a plurality of elastic members 8 forming leg gathers are provided in the vicinity of the leg opening s, and a good fit is realized by appropriately tightening the thigh.

  In the diaper 10 of this embodiment, the side seal | sticker part 4 is provided and the front body side f and the back body side r of a diaper are joined here. However, in this invention, it is good also as a tape type diaper which joins with a fastening tape, without providing the side seal part 4. FIG. Moreover, although the diaper 10 of this embodiment is illustrated as a diaper for infants, an diaper for adults may be used, and it can be set as the absorbent article made into a required form according to needs.

  What is necessary is just to use what is normally used for this kind of article | item as said each member which comprises the diaper 10 of this embodiment. For example, as the top sheet 2, a hydrophilic nonwoven fabric or an apertured film can be used. As the absorbent body 3, pulp, a highly water-absorbing polymer, or the like can be used. Various elastic materials can be used as the elastic members 6 and 8. The member which comprises the back seat | sheet 1, and its manufacturing method are demonstrated in detail later. Moreover, the method of assembling each of the above materials into a diaper is not particularly limited, and may be a normal manufacturing method applied to this type of disposable diaper.

2 is an enlarged cross-sectional view taken along the line II-II in FIG. As shown in FIG. 1 and FIG. 1, the disposable diaper 10 of the present embodiment is provided with an indicator 13 between the back sheet 1 and the absorber 3 that changes color when it comes into contact with moisture. In the present invention, the color change of the indicator may be a change that can be recognized by a visual change in color (which may be any of hue, saturation, and brightness), and L ^* a ^* b ^* color specification. The color difference (ΔE ^* ab = [(ΔL ^* ) ² + (Δa ^* ) ² + (Δb ^* ) ² ] ^1/2 ) in the system is preferably 1.5 or more. Moreover, it is preferable that it is the direction which b ^* value decreases. In the present invention, the term “color change” means that the color changes before and after contact with moisture, and is a concept that includes the disappearance of color upon contact with moisture and the appearance of color upon contact with moisture.

[L ^* a ^* b ^* L ^* value, a ^* value, b ^* value in the color system]
In the present invention, indicator discoloration is performed as follows when measuring using the L ^* value, a ^* value, and b ^* value in the L ^* a ^* b ^* color system. Measurement is performed using a hand-held spectral color difference meter NF777 (trade name) manufactured by Nippon Denshoku Industries Co., Ltd., with illumination condition C, viewing angle condition 2 °, front light reception condition = 0/45 °, and beam diameter φ10 mm. Find by condition. Specifically, when the measurement sample is in the form of a sheet (exterior nonwoven fabric, moisture permeable sheet, etc.), 10 sheets of the sheet-like material are stacked so that the position of the urine sign matches, and a backing sheet is 5 mm or more on the back side. In the case of an indicator, the reflected light is measured in a state where a plurality of sheets are stacked, and in the case of an indicator, a sufficient area is provided on the mount, and a plurality of mounts are stacked on the back surface so that the thickness is 5 mm or more. This is the value obtained by measuring with. The mount used is L ^* = 95 or more, a ^* = 0 ± 2.0, and b ^* = 0 ± 4.0 with the number of sheets used for measurement being stacked. Specifically, examples of the mount include L ^* = 96, a ^* = − 1.1, and b ^* = 3.7.

  In this embodiment, the indicator 13 is arranged inside the moisture-permeable sheet 11 of the back sheet 1 (see FIG. 2). Here, the indicator applies, for example, a hot melt composition in which a pH indicator (for example, bromophenol blue) or the like is mixed with an adhesive component to the absorbent facing surface of the moisture permeable sheet 11, and the absorbent body 3 is placed on the absorbent facing surface. It is arranged. At this time, a mount or the like may be provided between the absorber 3 and the indicator 13. Further, another functional sheet or the like may be provided between the moisture permeable sheet 11 and the indicator 13, between the moisture permeable sheet 11 and the exterior sheet 12, and outside the exterior sheet 12.

  In the present embodiment, the indicator 13 is linearly provided from the diaper bottom c to the front body f at the central portion in the diaper width direction. And it is provided so that three elongate lines may be juxtaposed in the diaper width direction. Thus, the discoloration of the indicator 13 at the bottom of the diaper (the crotch part of the wearer) c or the front body side (the abdomen side of the wearer) f where urination is particularly concentrated can be recognized. Further, since a plurality of indicators 13 (three in this embodiment) are juxtaposed in the diaper width direction in the form of narrow strips, visual changes are more easily recognized.

  In the diaper of this embodiment, the whole moisture-permeable sheet 11 is colored. The exterior nonwoven fabric is generally white and is somewhat affected by this background color. However, when the diaper is viewed from the outside through the exterior sheet 12 formed of the nonwoven fabric, the color of the backsheet 1 is generally the above. The colored moisture-permeable sheet 11 can be seen in color.

  In the diaper 10 of the present embodiment, the moisture permeable sheet 11 is colored with a colorant contained in the sheet. Here, “coloring by the colorant contained in the sheet” means that a part or the entire surface of the sheet is colored by the color of the colorant contained in the sheet, and the colorant is added on the surface of the sheet. It does not include those that are applied or are slightly soaked and colored in the vicinity of the surface, for example, those that are colored on the sheet surface by a normal printing method are not included. Specific examples of coloring with the colorant inside the sheet material include an embodiment in which a pigment or the like is contained in the composition forming the sheet in the production stage of the sheet and is formed into a predetermined sheet. Thus, it is preferable to use a colored calcium carbonate used as a filler and color it by functioning as a colorant.

  In the diaper 10 of the present embodiment, the color of the indicator 13 is yellow before the color change, and the color changes to blue-green upon contact with moisture. On the other hand, the moisture-permeable sheet is colored yellow. Thus, since the color before the color change of the indicator 13 and the moisture permeable sheet 11 or the back sheet 1 in the vicinity thereof are both yellow, the indicator 13 before the color change is inconspicuous and has a clean appearance without a sense of incongruity. . Here, in the present invention, the color of the colored moisture-permeable sheet 11 may be yellow. Here, the yellow color means that the L value in the Lab display system is 90 or more, the a value is ± 0.5 or less, and the b value is 0.9 or more. Then, when the indicator 13 comes into contact with moisture and turns blue-green, the blue-green line starts to appear in the yellowish backsheet 1, and the wearer or guardian (watcher) has the color. The change can be clearly recognized visually.

[L value, a value, b value in Lab color system]
In the measurement of the moisture-permeable sheet of the present invention, the L color value, a value, and b value in the Lab color system use a spectral color difference meter SE2000 (trade name) manufactured by Nippon Denshoku Industries Co., Ltd. unless otherwise specified. The light source is selected at 10 ° / D65, and the reflection or transmission is selected as reflected light measurement. The measurement sample is measured in a state where a plurality of samples are stacked so as to have a thickness of 5 mm or more.

  Further, the visibility in the above color change will be described in detail. A change in which a figure (three lines in the present embodiment) emerges in a part from the yellowed area as described above has the effect of attracting the viewer's interest and drawing out its attention. That is, the color change can be strongly impressed by giving some surprise as if a strange thing appeared in a place where there is no sense of incongruity.

  By the way, as described above, in a normal absorbent article, the indicator is disposed at least on the inner side of the back sheet (the back side of the back sheet as viewed from the viewer), and the indicator sees the sheet through the sheet. . For this reason, the indicator inevitably becomes a blurred color. For example, even if the color changes from yellow to blue-green, if the backsheet is white, the indicator remains white and the impression given to the viewer is weakened. In some cases, it may not be remembered whether the initial color of the indicator was yellow or turquoise. After all, whether the color is the one before the color change (before urination, etc.), or after the color change (after urination, etc.) ).

  On the other hand, according to the diaper 10 of the present embodiment, it is possible to make the viewer strongly recognize the discoloration of the indicator 13 by the visual action in which the color of the indicator and the outline thereof are raised. In addition, since the indicator 13 is raised only when there is a color change, even if the guardian forgets the color before and after the color change, it can be determined that there was urination without misidentification. In addition, in this embodiment, although the whole moisture-permeable sheet | seat 11 is colored, you may color only the periphery of the part which overlaps with the indicator 13, for example. However, considering the manufacturing method of adding a colorant to the resin composition forming the moisture permeable sheet as described later, it is preferable in terms of manufacturing efficiency and cost that the entire moisture permeable sheet is colored.

  Next, the indicator will be described. As described above, the indicator is discolored by contact with moisture. Examples of the color-changing substance contained therein include a pH indicator. As the pH indicator, when the absorbent article is a diaper as in the present embodiment, it is preferable to use one whose color changes before and after contact with urine. For example, bromophenol blue, methyl orange, arizan S, bromocresol green, methyl red, bromocresol purple, resazurin and the like that change color at pH 3-7 are preferred. In the present invention, the term “moisture” includes not only a liquid component composed solely of water but also an aqueous composition in which an acid, a base, a salt, an organic compound or the like is dissolved in water.

  As a method for immobilizing the indicator 13 on a predetermined sheet or the like, a method of applying to the surface as a hydrophilic composition in which a discoloring substance and an adhesive substance are mixed is simple and reliable. As the adhesive substance, a hydrophilic substance is preferable from the viewpoint of compatibility with the discoloring substance. Examples of such a substance include a hydrophilic polymer that functions as an adhesive. Examples of the hydrophilic polymer include polyethylene glycol (PEG), polypropylene glycol (PPG), polyvinyl alcohol (PVA), polyamide, vinyl pyrrolidone homopolymer, and the like. These hydrophilic polymers preferably have a number average molecular weight of 1,000 to 50,000, particularly 2,000 to 20,000 from the viewpoint of providing reliable fixation.

  As described above, the colored moisture-permeable sheet 11 in the present embodiment has the same color system as the color before the color change of the indicator 13. Specifically, the colored color of the moisture-permeable sheet 11 is represented by Lab color. The b value of the system is 0.9 or more, and this is preferably 1.0 or more. By setting it as such a hue, it can respond | correspond to the color of what is practical as an indicator, and can maintain the clean external appearance of an absorbent article.

  Since the indicator 13 is recognized from the outside of the diaper through the moisture permeable sheet 11 as described above, it is preferable to use a moisture permeable sheet having high transparency so as to improve the visibility of the indicator. From such a viewpoint, the light transmittance of the colored moisture-permeable sheet 11 is preferably 30% or more.

[Light transmittance]
In the present invention, the light transmittance is a haze meter manufactured by Nippon Denshoku Industries Co., Ltd., trade name “NDH5000”, and the value of total light transmittance Tt is measured based on JIS K7361-1. Arbitrary 10 points on the sheet to be measured are measured under these measurement conditions, and the average value is used as the light transmittance value in the present invention.

Moreover, it is preferable that the moisture permeable sheet 11 is liquid-impermeable and rich in moisture permeability. If the moisture permeability is low, the wearer's skin is likely to get wet and not good for the skin. The moisture permeability of the colored moisture permeable sheet is measured according to JIS Z0208 at an environmental temperature of 30 ° C., and is preferably 2.0 g / (100 cm ² · hr) or more, 2.5 g / (100 cm ² · hr) or more.

  Examples of the material used for the moisture permeable sheet 11 include a porous film. For example, the porous film is formed by melt-kneading a resin composition comprising a hydrophobic thermoplastic resin and a fine inorganic filler made of calcium carbonate or the like, or an organic polymer incompatible with the resin, to form a film. The film is obtained by uniaxial or biaxial stretching. Examples of the thermoplastic resin include polyolefin. Examples of the polyolefin include high-density polyethylene, low-density polyethylene, linear low-density polyethylene, polypropylene, and polybutene, and these can be used alone or in combination. The content of the thermoplastic resin in the resin composition is preferably 40% by mass or less from the viewpoint of satisfying all the b value, light transmittance, and moisture permeability.

As the moisture permeable sheet, a porous sheet having micropores for providing moisture permeability is preferably used. However, these fine holes normally diffuse light and reduce the b value of the moisture-permeable sheet. Therefore, in order to obtain high moisture permeability, even if the sheet is colored yellow, it acts in the direction of reducing the color. Moreover, the light transmittance of a normally moisture-permeable sheet will also fall by providing the said micropore. For this reason, it is difficult for the moisture-permeable sheet to satisfy all of high moisture permeability, high b value, and light transmittance.
On the other hand, in the present invention, the above three requirements can be satisfied at the same time, and the moisture content and b value can be further improved by adjusting the amount of filler if necessary, and sufficient light transmittance can be realized. can do.

  Although what is used as said filler is not specifically limited, For example, an inorganic filler is mentioned, It is preferable that a moisture-permeable sheet can be made porous and can fully provide moisture permeability. Examples of inorganic fillers include calcium carbonate, gypsum, talc, clay, kaolin, silica, diatomaceous earth, magnesium carbonate, barium carbonate, magnesium sulfate, barium sulfate, calcium phosphate, aluminum hydroxide, zinc oxide, titanium oxide, alumina, mica , Zeolite, carbon black, aluminum powder, iron powder and the like. These can be used alone or in combination of two or more. These inorganic fillers preferably have an average particle size of 0.3 to 8 μm and a maximum particle size of 20 μm or less from the viewpoint of ensuring the strength of the moisture-permeable sheet obtained and preventing sheet breakage during production. More preferably, the particle size is 0.5-5 μm and the maximum particle size is 15 μm or less.

Of the various inorganic fillers described above, calcium carbonate or barium sulfate is preferably used, and calcium carbonate is particularly preferably used. When using calcium carbonate, preferably it has a specific surface area of 16000~24000cm ² / g, more preferably 18000~22000cm ² / g. By using such a sheet, it is possible to obtain a sheet having high moisture permeability and high water resistance, that is, a sheet having a large number of dense holes and being hard to bleed and having sufficient strength. The inorganic filler in the resin composition is preferably 60% by mass or more. As a result, a moisture-permeable sheet having high moisture permeability can be obtained, the water resistance of the sheet can be maintained to make the liquid difficult to bleed, and sufficient strength and formability can be maintained. Moreover, although there is no upper limit in particular, it is preferable that it is 70 mass% or less when the productivity of a moisture-permeable sheet is considered.

  In the resin composition used as the moisture permeable sheet, in addition to the thermoplastic resin and the filler, a third component can be added in order to improve the supple texture and the handleability during production.

  In the diaper 10 of the present embodiment, a moisture permeable sheet is prepared by mixing a pigment or the like that does not impair moisture permeability in the resin composition as a colorant, or using a filler having a desired color as a colorant. It can be colored to a desired color. Since the diaper 10 of this embodiment has a coloring agent inside the sheet | seat material of a moisture-permeable sheet as mentioned above, and colored the sheet | seat by this, it is not necessary to provide a separate printing process after manufacturing a moisture-permeable sheet. Production efficiency is good. In particular, when the colorant to be contained in the moisture permeable sheet is colored calcium carbonate used as a filler, the number of steps and the number of members are not added to the conventional moisture permeable sheet manufacturing process, and high productivity is maintained as it is. Is done. Maintaining productivity and keeping costs low in this way is extremely important when considering the use mode in which disposable articles are discarded once used.

As described above, when a filler having a desired color is used as the filler for coloring the moisture-permeable sheet, it is preferable to use a desired color as the inorganic filler, and further to use a colored calcium carbonate having a desired color. More preferred. Examples of the colored calcium carbonate having a desired color include Softon 22S (trade name, exhibited by Okayama Mine) manufactured by Shiraishi Calcium Co., Ltd. The color of the colored calcium carbonate is not particularly limited. For example, a yellow or light blue one can be used, and among them, it is preferable to use yellow colored calcium carbonate. Regarding yellow colored calcium carbonate, specifically, when the colored calcium carbonate is measured as a powder (particle aggregate), the L ^* a ^* b ^* b ^* value in the color system is 1.1 or more. Preferably there is. Thus, by using what has a desired color as colored calcium carbonate, the function as a filler when forming a moisture-permeable sheet and the function as a colorant can be satisfied together.
In the present invention, the b ^* value in the L ^* a ^* b ^* color system of the inorganic filler is filled with powder in a case using CR-400 (trade name) manufactured by Konica Minolta Sensing unless otherwise specified. Place the measuring instrument on the flat surface and measure. At this time, a C light source is used as the light source.

  By making calcium carbonate colored and functioning as a colorant, it is possible to achieve a desired color efficiently and at a low cost without using a separate colorant such as an expensive pigment or adding an extra step. A colored moisture-permeable sheet can be produced. Therefore, it is possible to suitably realize an important cost reduction in the disposable article. Further, since calcium carbonate is originally used as a filler in a moisture permeable sheet, it is preferable in that it is almost unnecessary to consider the influence on various performances and quality of the moisture permeable sheet.

The content of calcium carbonate contained in the moisture permeable sheet 11 is preferably 60% by mass or more from the viewpoint of the filler function and the coloring function, and is 70% by mass or less from the viewpoint of sheet productivity. Is more preferable. The basis weight of the moisture permeable sheet 11 is preferably 10 to 40 g / m ² . Such a basis weight is preferable because the visual change of the indicator 13 can be easily recognized from the outside of the diaper and a flexible feel can be obtained.

As the exterior sheet 12, it is preferable to use a soft material that has a high light transmittance so that the indicator 13 can be sufficiently seen through and that can provide a good touch to the wearer and the guardian. Specifically, it is preferable to use a nonwoven fabric having the above properties. The basis weight of the nonwoven fabric is preferably 5 to 45 g / m ² and more preferably 10 to 40 g / m ² in consideration of the above properties. The light transmittance of the exterior sheet 12 is preferably 30% or more, and more preferably 40% or more. Although the moisture permeability of the exterior sheet 12 is not particularly limited, it is preferable that the exterior sheet 12 has sufficient moisture permeability.

  As the nonwoven fabric used for the exterior sheet 12, for example, a single fiber of a thermoplastic resin made of a polyolefin such as polyethylene or polypropylene, or a polyester such as polyethylene terephthalate, or a core-sheath type or a side-by-side type using two or more of these resins. Nonwoven fabric composed of a composite fiber having the following structure.

  As the non-woven fabric used for the exterior sheet 12, it is preferable to use a non-woven fabric with a high transparency of the ground color because the visibility of the visual change of the indicator is enhanced. However, the outer sheet | seat 12 should just have the high transmittance | permeability of the overlapping part with the area | region which has arrange | positioned the indicator 13 with respect to the diaper thickness direction, and its periphery. Furthermore, the exterior sheet 12 may be colored in the same yellow color as the moisture permeable sheet. In addition, a pattern or a pattern may be provided on the exterior sheet 12 in order to improve the visibility of the visual change of the indicator. The same applies to the moisture permeable sheet 11. For example, a pattern such as an animal or a character may be drawn in order to further improve the visibility of the indicator or improve the appearance image of the article.

  The exterior sheet 12 and the moisture-permeable sheet 11 may be bonded in part or may be bonded over the entire surface. It is preferable to join the entire surface in consideration of the strength and the like when the back sheet 1 is used. For example, the exterior sheet 12 and the moisture permeable sheet 11 can be joined by a hot melt adhesive or the like.

  The absorbent article of the present invention is not particularly limited as long as it absorbs and holds liquid excreted or leached from the wearer's body, and is preferably an article used in contact with or close to the wearer's skin. . Specifically, it is preferably a disposable absorbent article that is washed as it is and is not premised on reuse. For example, in addition to the disposable diaper described above, it should be used as a sanitary napkin, panty liner, urine pad, etc. Is preferred.

  The present invention will be described more specifically with reference to examples and comparative examples, but the present invention should not be construed as being limited thereby.

(Example)
Polyolefin resin (manufactured by Prime Polymer Co., Ltd., UZ2520F [trade name]) 34.0% by mass, fatty acid (manufactured by Kao Corp., LUNAC S-40 [trade name]) 0.92% by mass, polyester (Kao) Exepearl TM20-AS [trade name] 4.01% by mass, calcium carbonate (Shiraishi Calcium Co., Ltd., Softon 22S, trade name, Okayama Mine Exhibit, Lab color system b value : 1.2) 61.07 mass% was prepared, and these were stirred with a Henschel mixer and then heated and mixed with a twin-screw kneader to produce a master batch. Using this master batch, a sheet was formed by an inflation forming apparatus. Further, this sheet was heated to 70 ° C., stretched at a magnification of 2.3 times in the sheet flow direction, and the basis weight after stretching was set to 20 g / m ² to prepare a porous sheet (test body 1).

(Comparative Example 1)
Instead of the calcium carbonate, 57.70% by mass of ACE25 (trade name, Lab color system b value: 0.2) 57.70% by mass was used instead of the calcium carbonate, and the amount of the polyester was 4 A porous sheet (test body 1c) was prepared in the same manner except that the amount of the fatty acid was 0.000% by mass, the amount of the fatty acid was 0.90% by mass, and the amount of the polyolefin resin was 37.4% by mass.

(Reference Example 1)
The amount of the calcium carbonate is 57.70% by mass, the amount of the polyester is 4.00% by mass, the amount of the fatty acid is 0.90% by mass, and the amount of the polyolefin resin. Was 37.4% by mass, and a microporous sheet (test body 1s) was prepared in the same manner except that the draw ratio was 2.7 times.

(Reference Example 2)
The amount of the calcium carbonate is 57.70% by mass, the amount of the polyester is 4.00% by mass, the amount of the fatty acid is 0.90% by mass, and the amount of the polyolefin resin. Was 37.4% by mass, and a microporous sheet (test body 2s) was prepared in the same manner except that the draw ratio was 2.1 times.

  The b color value, L value, a value, light transmittance, and moisture permeability of each of the above porous sheet specimens were measured. At this time, the color of each test body judged visually was confirmed. Moreover, the diaper shown in FIG.1 and FIG.2 was produced using each porous sheet test body, and test evaluation of the visibility of the piss sign by the discoloration of each diaper indicator, and the wearing comfort of a diaper with a panel of 10 people. did. The results are summarized in Table 1 below.

The visibility of the pee sign was evaluated by a visual test using a panel of 10 people, and the results were classified as follows.
When all 9 or 10 people answered that it was easy to judge
When there are 7 or 8 people who answered that it is easy to judge
When 4 to 6 people answered that it was easy to judge
When there are 3 or less people who answered that it is easy to judge

About the wearing comfort of the diaper, the mother judged from the wetness of Aka-chan's buttocks after use in a panel test of 10 people, and the results were classified as follows.
When all 9 or 10 people feel that they are comfortable diapers
When 7 or 8 people answered that they feel comfortable diapers
When 4 to 6 people say they feel comfortable diapers ... △
When there are 3 or less people who answered that they feel comfortable diapers

  As shown in Table 1, according to the present invention, it is easy to visually recognize the discoloration of the indicator that informs the pee of an infant or the like in the diaper, and it is understood that good wearability is realized by high moisture permeability.

FIG. 1 is a perspective view schematically showing a pants-type disposable diaper as a preferred embodiment of the absorbent article of the present invention. 2 is an enlarged cross-sectional view taken along the line II-II in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Back sheet 2 Top sheet 3 Absorbent body 4 Side seal part 6 Elastic member for waist gathers 8 Elastic member for leg gathers 10 Absorbent article (pants-type diaper)
11 Moisture permeable sheet 12 Exterior sheet 13 Indicator

Claims (5)

An absorbent article having an absorbent body and a backsheet disposed outside the absorbent body, wherein an indicator that changes color by contact with moisture is disposed between the absorbent body and the backsheet, the backsheet Has a moisture-permeable sheet on the absorber side and an exterior sheet on the outside thereof, and the moisture-permeable sheet is colored yellow by the colorant contained in the moisture-permeable sheet, and the colored moisture-permeable sheet An absorbent article, wherein the light transmittance of the sheet is 30% or more, and the moisture permeability of the moisture permeable sheet is 2.0 g / 100 cm ² · h or more.   The absorbent article according to claim 1, wherein the moisture-permeable sheet is colored with a color of 1.0 or more in the b value of the Lab color system.   The absorbent article according to claim 1 or 2, wherein the colorant is colored calcium carbonate.   The absorptive article given in any 1 paragraph of Claims 1-3 whose content rate of colored calcium carbonate contained in said moisture-permeable sheet is 60 mass% or more. The absorbent article according to claim 3 or 4, wherein the colored calcium carbonate has a b ^* value of L ^* a ^* b ^* color system of 1.1 or more when powdered.

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