Absorbent articles

Abstract

To provide an absorbent article which can make information on a diaper more visible to a user.SOLUTION: An absorbent article includes: a longitudinal direction which extends from an abdominal side to a back side through a crotch; a width direction perpendicular to the longitudinal direction; a liquid permeable top sheet; a liquid impermeable back sheet; an absorber interposed between the top sheet and the back sheet; a cover sheet joined to a non-skin surface side of the back sheet; a pair of side sheets provided in the longitudinal direction of a pair of side edge parts of the absorber; and a display area in which a display is formed within a range including exclusively or partially an area overlapped with wrinkles formed on a sheet member constituting the absorbent article; or an area including a part. In the display area, the wrinkles prevent a part or the entire of information from being displayed, and the entire information is displayed when the wrinkles are smoothed away.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to an absorbent article. [Background technology]

[0002] 2. Description of the Related Art Absorbent articles such as disposable diapers (hereinafter simply referred to as "diapers") that guide excreted body fluids (hereinafter simply referred to as "body fluids") into an absorbent body for absorption have been widely known.

[0003] Diapers may have wrinkles due to packaging, compression grooves in the absorbent body, gathers for fitting to the wearer's skin, etc., and may also have information such as size and pattern printed on the diaper. Summary of the Invention [Problem to be solved by the invention]

[0004] When the diaper is used, the wrinkles may make it difficult to see the information printed on the diaper. Therefore, a structure is needed that can grasp the wrinkles that occur in the diaper and make the information printed on the diaper easier to see.

[0005] An object of the present invention is to provide an absorbent article which allows a user to easily visually recognize information about the diaper. [Means for solving the problem]

[0006] One form of the present invention comprises a longitudinal direction extending from the ventral side through the crotch to the dorsal side, a width direction perpendicular to the longitudinal direction, a liquid-permeable top sheet, a liquid-impermeable back sheet, an absorbent body interposed between the top sheet and the back sheet, a cover sheet joined to the non-skin-facing side of the back sheet, a pair of side sheets provided along the longitudinal direction of a pair of side edge portions of the absorbent body, and a display area in which an indication is formed in a range including only or a part of an area overlapping with wrinkles formed in a sheet member constituting the absorbent article, wherein the display area is characterized in that some or all of the information is not displayed due to the wrinkles, and all of the information is displayed by smoothing out the wrinkles. Effect of the Invention

[0007] According to the present invention, the user can appropriately grasp information about the diaper, and can obtain information necessary before wearing the diaper and information necessary after wearing the diaper. [Brief description of the drawings]

[0008] [Figure 1] 1 is a perspective view of an example of a diaper according to an embodiment of the present invention, seen from the front side. FIG. [Diagram 2] FIG. 2 is a perspective view of the diaper shown in FIG. 1 as seen from the rear side. [Diagram 3] FIG. 3 is an exploded perspective view of the diaper shown in FIGS. 1 and 2. [Figure 4] 1 is a plan view of a diaper in an extended state according to an embodiment of the present invention, as viewed from the top sheet side. [Diagram 5] 1 is a plan view of a diaper in an unstretched state according to an embodiment of the present invention, as viewed from the cover sheet side. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] An embodiment of an absorbent article according to the present invention will be described in detail with reference to Figs. 1 to 6. However, the present invention is not limited to this embodiment. In the claims, specification, and drawings of the present invention, the longitudinal direction is defined as the direction extending from the abdominal side of the wearer of the absorbent article through the crotch to the back side. The width direction is defined as the direction perpendicular to the longitudinal direction.

[0010] First, an embodiment in which the present invention is applied to an open-type disposable diaper will be described below.

[0011] <Major components of diapers> FIG. 1 is a perspective view of an example of a diaper according to an embodiment of the present invention, as viewed from the front side. FIG. 2 is a perspective view of the example of the diaper shown in FIG. 1, as viewed from the rear side. As shown in FIGS. 1 and 2, the diaper 10 according to this embodiment is an open-type disposable diaper, and has a front body region 10F, a rear body region 10R, and a crotch region 10C connecting the front body region 10F and the rear body region 10R. In addition, a waist opening 10W is formed by the front body region 10F and the rear body region 10R to surround the waist of the wearer when worn. Similarly, a pair of left and right leg openings 10L is formed by the lower ends of the front body region 10F and the rear body region 10R and the crotch region 10C to surround the thighs of both legs of the wearer. In the center of the waist opening 10W on the rear body region 10R side, a stretchable member such as an elastic sheet is arranged in the width direction (left and right direction in FIG. 2) to improve the fit around the waist when worn, and a waist gather is formed. In this embodiment, a display area is formed in the rear body region 10R in the crotch direction of the waist opening 10W on the rear body region 10R side and in an area including the position where gather wrinkles 101a, 102a are formed when the stretchable member is in a non-stretched state. The display area includes a first display area 101 and a second display area 102 (see FIG. 5 and FIG. 6 described later). Details will be described later.

[0012] When worn, the front body region 10F is located on the wearer's abdomen, and the back body region 10R is located on the wearer's back. When worn, the crotch region 10C covers the wearer's crotch, and the wearer's legs are passed through the pair of left and right leg openings 10L. Therefore, the leg openings 10L are located somewhere between the base of the wearer's legs and the thighs.

[0013] The imaginary line P extends from the ventral side to the dorsal side in the center of the diaper, passing through the crotch portion. Specifically, if the waist side of the diaper is defined as the top and the crotch side as the bottom, the imaginary line P extends vertically along the surface of the diaper, and also vertically on the dorsal side via the crotch portion.

[0014] The cover sheet 11 further includes a pair of first engaging members, fastening tapes 10A, at both ends on the back side, and a front patch 10B, which is a second engaging member that engages with the fastening tapes 10A and extends parallel to the edge of the ventral side of the cover sheet 11.

[0015] In this embodiment, a pair of fastening tapes 10A are adhered to both left and right edge portions of the rear body region 10R of the cover sheet 11 located on the outside of the diaper 10, which are overlapped and connected to both left and right edge portions of the front body region 10F when worn to form leg openings 10L. The fastening tapes 10A and the front patch sheet 10B have a structure such as a mechanical fastener, and the fastening tape 10A is repeatedly and releasably joined to the front patch sheet 10B adhered to the cover sheet 11 of the front body region 10F.

[0016] In addition, the second display area 102, which will be described later, displays a pattern or figure including lines that are approximately parallel to the extension direction of the front patch sheet 10B, and is located on the crotch side of the front patch sheet 10B. This makes it possible to highlight the position of the front patch sheet 10B. In addition, the user can easily recognize the position of the front patch sheet 10B, making it easier to engage the fastening tape 10A and the front patch sheet 10B.

[0017] Furthermore, in this embodiment, a second display area 102 is formed in the front body region 10F, located closer to the crotch than the front patch sheet 10B and approximately parallel to the bottom side of the front patch sheet 10B. A pattern or figure including straight lines and curves is formed in this second display area 102. Since the second display area 102 is located closer to the crotch than the front patch sheet 10B and approximately parallel to the front patch sheet 10B, the user can easily recognize the position of the front patch sheet 10B when wearing the garment.

[0018] Fig. 3 is a schematic exploded perspective view of the diaper 10 shown in Fig. 1 and Fig. 2, and Fig. 4 is a plan view of the diaper 10 in an extended state according to one embodiment of the present invention, as viewed from the top sheet 14. For ease of explanation, the absorbent body 13 in Fig. 3 and the diaper 10 in Fig. 4 are shown in a partially cutaway state.

[0019] As shown in FIG. 3, the diaper 10 includes an elastic member that is arranged and fixed in a stretched state so as to be sandwiched between a plurality of sheet members to form gathers. The plurality of sheet members in this embodiment include, for example, a liquid-permeable top sheet 14, a liquid-impermeable back sheet 12, an absorbent 13 interposed between the top sheet 14 and the back sheet 12, a cover sheet 11 joined to the non-skin-facing side of the back sheet 12, and a pair of side sheets 15 provided along the longitudinal direction of a pair of side edges of the absorbent 13. The diaper 10 in this embodiment has a layered structure in which, from the outside, the cover sheet 11, the back sheet 12, the absorbent 13, the top sheet 14, and a pair of side sheets 15 are layered. The diaper 10 further includes an elastic member that is arranged and fixed in a stretched state so as to be sandwiched between two sheets of the top sheet 14, the back sheet 12, the cover sheet 11, and the side sheet 15 constituting the diaper 10, which is an absorbent article in this embodiment described later, to form gathers. The first display area, which will be described later, is an area in which the display is formed in a range including only or a part of an area overlapping with wrinkles formed due to the stretching of the stretchable member. This allows the user to not see the information displayed in the first display area by putting the diaper in a non-stretched state, and to see and view the information displayed in the first display area by putting the diaper in a stretched state.

[0020] In the absorbent 13, compressed grooves are formed from the skin-facing side to the non-skin-facing side or from the non-skin-facing side to the skin-facing side, and wrinkles are formed by the compressed grooves, hiding part or all of the information. In this embodiment, as shown in FIG. 4, the absorbent 13 has a plurality of recesses 20 (hereinafter also referred to as compressed grooves) formed by compression from the skin-facing side to the non-skin-facing side. That is, a plurality of compressed grooves 20 are formed in a part of the compressed grooves 20. As shown in FIG. 4, the compressed grooves 20 are formed, so that the compressed grooves 20 are easily bent, and the fit of the diaper 10 can be improved. In addition, the compressed grooves 20 are continuously formed, so that air can pass through to the ventral side or the dorsal side, and breathability can be ensured. In addition, the discharged body fluid can be quickly diffused, and the absorbent 13 can be used as a whole and efficiently absorbed by the absorbent 13.

[0021] In the present invention, the concept of a plurality of compressed grooves 20 includes not only a plurality of individual compressed grooves 20 that are not physically continuous with each other, but also a physically continuous structure formed by overlapping compressed grooves 20 as a plurality of constituent units. The constituent units include, but are not limited to, straight lines and continuous curves that do not have any bends (corners) therein. In the present embodiment, the absorbent body may be configured not to have a plurality of compressed grooves.

[0022] For example, an adhesive is applied to the surface where the top sheet 14 and the absorbent body 13 come into contact, and the compressed grooves 20 are provided by compressing the laminate of the absorbent body 13 and the top sheet 14. This compression is performed, for example, by an embossing roll. As a result, the top sheet 14 and the absorbent body 13 are engaged and integrally bonded throughout the entire compressed groove 20, from the bottom surface to the wall surface of the compressed groove 20. With this configuration, the top sheet 14 and the absorbent body 13 are integrally formed, so that the top sheet 14 and the absorbent body 13 are firmly bonded together and the top sheet 14 is less likely to peel off, and even if the absorbent body 13 expands after urination, the top sheet 14 stays aligned with the grooves, maintaining the grooves.

[0023] 2 and 3, a pair of cutouts 11N that become leg openings 10L are formed on the left and right sides of the crotch region 10C of the cover sheet 11. A pair of rubber threads 16 for forming leg gathers (leg gathers) are bonded in a stretched state between the cover sheet 11 and the pair of side sheets 15. In this embodiment, first display regions 101 are formed on the left and right sides of the crotch region 10C in regions including positions where gather wrinkles 101a are formed when the rubber threads 16, which are stretchable members, are in a non-stretched state (see FIG. 5 described later). Details will be described later.

[0024] The top sheet 14 is made of a nonwoven fabric having liquid permeability. The back sheet 12 is joined to the cover sheet 11, the absorbent 13 is disposed between the back sheet 12 and the top sheet 14, and the top sheet 14 is joined to the back sheet 12 via the absorbent 13. In addition, an elastic sheet 10D is joined to the back sheet 12 in an area corresponding to the upper end of the rear body region 10R, which extends along the width direction of the back sheet 12 and provides a moderate wearing comfort around the waist of the wearer. In the present invention, compressed grooves may be formed in vertical stripes in the longitudinal direction of the diaper 10. Furthermore, a second display area is formed around the elastic sheet 10D and the front patch sheet 10B on the skin-facing side of the top sheet 14. Details will be described later.

[0025] The back sheet 12 of this embodiment is provided with an indicator 10E, which changes color when wet with body fluids, on the side in contact with the absorbent body 13, as shown by the dashed line in Figures 1 and 2. The indicator 10E is provided along the longitudinal direction, from the crotch region 10C to a part of the front body region 10F and the back body region 10R, at a position sandwiched between the back sheet 12 and the absorbent body 13. In this embodiment, two indicators 10E are provided in a band shape in the longitudinal direction of the back sheet 12 on the side in contact with the absorbent body 13.

[0026] The indicator 10E is a strip-shaped portion coated on the absorbent article so that when moisture is detected, it changes color, making it possible to visually confirm from the outside when the absorbent body of the absorbent article has sufficiently absorbed bodily fluids. This is made of a material that reacts with moisture or a material that reacts due to a change in pH after coming into contact with moisture.

[0027] Furthermore, coloring includes not only "coloring" where colorlessness changes to color, but also "discoloration" where color changes and "discoloration" where coloredness changes to colorless.

[0028] The absorbent body 13 of this embodiment, located under the top sheet 14, is formed by covering an absorbent core 17 mainly made of pulp and SAP with a covering member (core wrap) 18 such as tissue or nonwoven fabric. A seam formed by wrapping the absorbent core 17 with the covering member 18 is formed on the upper surface of the absorbent body 13 and extends in the longitudinal direction, as shown in FIG. 3, for example. The absorbent body 13 of this embodiment has an elongated shape that spans the front body, crotch area, and rear body. Although the diaper 10 of this embodiment uses the absorbent body 13 wrapped with the covering member 18, the absorbent article of the present invention may use an absorbent core 17 that is not wrapped with the covering member 18.

[0029] In this embodiment, a plurality of compressed grooves 20 are formed in the absorbent body 13, and the plurality of compressed grooves 20 form a lattice pattern as a whole. Specifically, the plurality of compressed grooves 20 are formed on the surface of the absorbent body 13 in a diagonal lattice pattern, as shown in Figs. 3 and 4. The position of the imaginary line P on the absorbent body 13 extends from the upper end of the front body part to the lower end of the back body part, as shown in Fig. 4, and the imaginary line P extends in the longitudinal direction when the absorbent body 13 has an elongated shape. Each of the plurality of compressed grooves 20 extends at an incline to the left and right with respect to the imaginary line P. In this embodiment, the plurality of compressed grooves 20 in the absorbent body 13 form a lattice pattern as a whole, but this is not limited thereto, and the absorbent body 13 may be formed with a plurality of compressed grooves 20 in vertical stripes in the longitudinal direction. This allows body fluid to be dispersed in the longitudinal direction. In this embodiment, in order to avoid wrinkles on the non-skin-facing side of the diaper 10 having the lattice pattern formed on the absorbent body 13, information, etc. may be displayed in the area surrounded by the multiple compressed grooves 20 of the absorbent body 13. This makes it easier for the user to visually recognize the information, etc.

[0030] In this embodiment, a pair of hydrophobic side sheets 15 that form three-dimensional gathers are provided on both left and right side edges of the top sheet 14 in the width direction. The pair of side sheets 15 are members that stand up along both left and right side edges of the absorbent body 13 when worn, and prevent lateral leakage of discharged body fluids. The outer edge portions of the pair of side sheets 15 are formed with cutout portions 15N in the same shape as the pair of cutout portions 11N of the cover sheet 11. Each of the pair of side sheets 15 has a thread rubber 19 as a three-dimensional gather stretch member arranged in a stretched state in such a manner that the inner edge portion is folded back toward the absorbent body 13 and held. When the thread rubber 19 contracts, the pair of side sheets 15 rise up toward the wearer's skin contact direction. The three-dimensional gathers can be formed by adopting a known configuration used in conventional disposable diapers. For example, the three-dimensional gathers can be formed by sandwiching and fixing a stretched three-dimensional gather stretch member between layers of a water-repellent sheet.

[0031] <First display area and second display area> FIG. 5 is a plan view of a diaper 10 in an unstretched state according to one embodiment of the present invention, viewed from the cover sheet 11 side, and is a diagram for explaining an example of a first display area 101 and a second display area 102, each of which includes wrinkles in an unstretched state.

[0032] The first display area 101 displays unnecessary information before the diaper is put on. In this embodiment, the first display area displays, for example, diaper size information "M", brand information, and manufacturer information "ABCD". This allows the user to know the size, brand, and manufacturer name of the diaper worn by the wearer, and can obtain information when purchasing. In this embodiment, information such as size information is printed and displayed on the non-skin-facing side of the back sheet, but is not limited to this, and may be printed on a sheet that can be recognized from the outside, such as a cover sheet.

[0033] In the first display area 101, some or all of the information is hidden due to wrinkles, and all of the information is displayed by smoothing out the wrinkles. In this embodiment, the first display area 101 is an area in which an indication is formed in an area that overlaps with the wrinkles or depressions caused by the compressed grooves, and in which some or all of the manufacturer information "ABCD" is hidden. In a non-stretched state, the first display area 101 is formed in the back sheet 12, and some of the manufacturer information "ABCD" is hidden by the compressed grooves 20 formed in the absorbent body 13. This makes it possible to prevent information that is unnecessary for the user from being visible before the diaper is put on by the wearer. On the other hand, in this embodiment, the first display area 101 is formed on the back sheet 12, but this is not limited to this. If the compressed grooves 20 formed in the absorbent body 13 are formed from the non-skin side to the skin side, providing the first display area 101 on the back sheet 12 will cause the first display area 101 to fall into the compressed grooves 20, making it difficult to recognize, and therefore the first display area 101 may be formed on the cover sheet 11.

[0034] In this embodiment, the first indication region 101 is an area in which an indication is formed in an area overlapping with wrinkles or depressions caused by the compressed grooves, and is an area in which part or all of the indicator 10E, which changes color when wet with body fluids, is hidden. In a non-stretched state, the first indication region 101 is formed in the back sheet 12, and part of the indicator 10E is hidden by the compressed grooves 20 formed in the absorbent body 13. This makes it possible to prevent unnecessary information from being visually recognized by the user before the diaper is put on by the wearer.

[0035] In this embodiment, the width of the indicator 10E may be such that it is partially or completely hidden by the wrinkles or depressions caused by the compressed grooves, and is preferably such that it is partially hidden. This reduces the chance of the indicator 10E coming into contact with moisture in the air, thereby enhancing the effect of preventing the indicator 10E from changing color before use.

[0036] In this embodiment, two indicators 10E are provided, but the number is not limited to this, and one indicator or three or more indicators may be provided.

[0037] Furthermore, in this embodiment, the first display region 101 forms an indication in an area overlapping with the gathered wrinkles 101a formed with the contraction of the elastic thread rubber 16 and the elastic sheet 10D, which are stretchable members. The first display region 101 forms an indication in an area including wrinkles caused by gathers formed around the waist on the non-skin side and gathers formed around the legs, and in the area surrounding them. In this embodiment, as shown in Fig. 5, the first display region 101 is formed in the center of the waist gathers. At this time, the indication of the size information "M" in the first display region 101 is partially visible, but is not enough for the user to recognize it as an indication.

[0038] The first display area 101 is displayed when the elastic member is in an extended state. That is, as shown in FIG. 2, the first display area 101 is displayed when the elastic member, that is, the rubber thread 16 and the elastic sheet 10D, are in an extended state. This allows the user to recognize the size information "M" displayed in the first display area 101. Note that in this embodiment, the display in the first display area 101 is partially visible when the elastic member is contracted, but the present invention is not limited to this and may be configured such that the display is completely invisible when the elastic member is contracted.

[0039] The second display area 102 displays information necessary before putting the diaper on. In this embodiment, the second display area displays information on the orientation of the diaper, such as "front" or "back," "left" or "right," and patterns or figures to indicate the position of the tape. This allows the user to understand the front and back of the diaper when putting it on the wearer. Note that in this embodiment, information such as the front and back information of the diaper is printed and displayed on the back sheet, similar to the first display area, but is not limited to this and may be printed on a cover sheet or the like as long as it is a sheet that can be recognized when putting the diaper on.

[0040] In this embodiment, the second display area 102 is an area in which an indication is formed in a range that does not overlap with the first display area, and displays a pattern or figure including a line approximately parallel to the lower side of the front patch sheet 10B. This makes it easier for the user to visually recognize the position of the front patch sheet 10B, and makes it easier to engage the fastening tape 10A with the front patch sheet 10B when wearing it. In this embodiment, the second display area 102 displays a pattern or figure, but it may also display only letters or a combination of letters and figures. This makes it easier for the user to visually recognize the position of the front patch sheet 10B with the second display area 102.

[0041] In addition, in this embodiment, a pattern or figure including a line approximately parallel to the bottom side of the front patch sheet 10B is displayed in the second display area 102, but this is not limited to this, and letters or the like may be formed. As described above, in the diaper in a non-stretched state, a part of the display is visible in the second display area 102, which allows the user to understand that there is some display, and the user stretches the folds 102a to try to recognize the display. This allows the pattern to be displayed in the second display area 102, making it easier for the user to visually recognize the position of the front patch sheet 10B. In this embodiment, a pattern is displayed in the second display area 102, but this is not limited to this, and any information necessary when putting on the diaper may be displayed, such as "front" or "back".

[0042] The display area forms an indication in an area overlapping with creases formed when the diaper 10 is stored in a package. The diaper 10 is generally folded and stored in a package, and the first display area 101 and the second display area 102 form indications in an area including the creases formed when the diaper 10 is folded. The first display area 101 and the second display area 102 are also displayed when the creases are smoothed out. This allows the indications in the first display area 101 and the second display area to be recognized by the user.

[0043] In this way, the user can appropriately grasp information about the diaper, and can obtain information that will be required after wearing the diaper.

[0044] <Other> The present invention is not limited to the above-described embodiment or the modified examples described throughout the specification, and appropriate changes and modifications can be made without departing from the technical concept of the present invention.

[0045] For example, the structure of the diaper according to the above embodiment or its modified example is not limited to the above-mentioned flat-type, and may be any structure as long as it is an absorbent article including the structure defined in the claims. For example, the present invention is also applicable to pants-type disposable diapers, absorbent pads, etc.

[0046] In addition, the above-described embodiment or its modified examples are not limited to diapers for infants, but are applicable to various absorbent articles such as diapers for adults.

[0047] In addition, in the above embodiment, the indicator 10E is provided on the skin facing side of the back sheet 12, but this is not limited thereto, and the indicator 10E may be provided on the non-skin facing side of the absorbent body 13. [Explanation of symbols]

[0048] 10 Diapers (absorbent articles) 10A Fastening Tape 10B Front patch seat 10F Front body area 10R Back area 10C Inseam area 10W Waist opening 10L Leg opening 10E Indicator 11 Cover Sheet 12 Back Seat 13 Absorber 14 Top sheet 15 Side seat 16 Rubber thread (elastic material) 20 Multiple compression grooves 10D Elastic sheet (elastic material) 101 1st display area 101a Gathered wrinkles 102 Second display area 102a Folds

Claims

1. the absorbent article has a longitudinal direction extending from the ventral side through the crotch to the dorsal side, a width direction perpendicular to the longitudinal direction, a liquid-permeable top sheet, a liquid-impermeable back sheet, an absorbent body interposed between the top sheet and the back sheet, a cover sheet joined to the non-skin-facing side of the back sheet, a pair of side sheets provided along the longitudinal direction of a pair of side edge portions of the absorbent body, and a display region in which a display is formed only in an area overlapping with wrinkles formed in a sheet member constituting the absorbent article or in a range including a part of the area, The display area includes a first display area in which some or all of the information is not displayed due to the wrinkles and all of the information is displayed by smoothing the wrinkles, and a second display area in which information is always displayed in a range that does not overlap with the first display area, An absorbent article, characterized in that different information is displayed in the first display area and the second display area, and information that is unnecessary before putting the article on is displayed in the first display area, and information that is necessary before putting the article on is displayed in the second display area.

2. The absorbent article according to claim 1, characterized in that the absorbent body has compressed grooves formed from the skin side to the non-skin side or from the non-skin side to the skin side, and the wrinkles are formed by the compressed grooves, thereby hiding some or all of the information.

3. The absorbent article according to claim 2, characterized in that the first display area is an area in which a display is formed in an area that overlaps with the wrinkles generated by the compression grooves, and in which part or all of the information is hidden.

4. The absorbent article described in claim 1, characterized in that the absorbent article further comprises an elastic member that forms gathers by being arranged and fixed in a stretched state so as to be sandwiched between a plurality of the sheet members, and the first indication area is an area in which an indication is formed in an area that includes only or a portion of the area overlapping with the wrinkles formed due to contraction of the elastic member.

5. 5. The absorbent article according to claim 1, wherein the sheet member on which the display area is formed is the back sheet.

6. 6. The absorbent article according to claim 1, wherein the first indication area is an area in which at least a part of an indicator that changes color when wetted with liquid is hidden.

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