JP3616755B2 - Disposable diapers - Google Patents

Description

[0001]
[Industrial application field]
The present invention relates to a disposable diaper, and more particularly to a disposable diaper provided with an indicator that can notify a mother that urination has occurred.
[0002]
[Prior art]
The disposable diaper disclosed in Japanese Utility Model Laid-Open No. 3-58416 includes a discoloration layer formed on the inner surface of a polyethylene back sheet, and a colored transmission layer formed so as to cover the discoloration layer. The indicator means consisting of is adopted. According to this means, excreted urine may penetrate into the permeation layer reaches the color-change layer, Runode to elicit the color tone of the transmissive layer by transparency the modified color layer, viewing the color tone from the outside of the diaper can do. The mother sees the color and finds out that the diaper is in exchange.
[0003]
[Problems to be solved by the invention]
Contact Keru indicator means to the prior art is provided with the mechanism that can manifest, there is no mechanism for reliably penetrate urine discharged into the diaper until the indicator means. Since the indicator means composed of the color changing layer and the transmissive layer is formed on a hydrophobic polyethylene film, the indicator means and its surroundings may be difficult to get wet. In addition, it is conceivable that the liquid-absorbent core and the indicator means are joined with a hydrophilic adhesive, and the urine can penetrate into the indicator means through the adhesive, but it is short to meet the high diaper production rate. There is no such adhesive that solidifies over time. Therefore, it is difficult to say that the indicator means of the prior art is surely manifested when there is urination. In addition, since the polyethylene back sheet does not absorb any kind of paint used to form the discoloration layer or the transmission layer, in the diaper production process, it is necessary to take time to dry these layers sufficiently. Cannot proceed to the process. For this reason, the production rate of diapers is significantly limited.
[0004]
Therefore, an object of the present invention is to facilitate the penetration of urine into the indicator means without affecting the productivity of the disposable diaper.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention presupposes that a liquid-absorbent core is interposed between a liquid-permeable top sheet and a liquid-impervious back sheet, and a body fluid is present in any of the front and rear side trunk regions. It is a disposable diaper having indicator means that can be identified from the outside by revealing that body fluid has been excreted when wet.
[0006]
Under such assumption, the present invention is characterized by a. The back sheet is light transmissive; b. The indicator means has a hydrophilic base sheet, a first paint layer having a color tone different from that of the base sheet and formed on one side of the base sheet , and formed on the other side of the base sheet It has been constructed and a second coating layer capable to elicit the color tone becomes transparent in a wet state while substantially hiding the color of the first paint layer in a dry state, c. The first coating layer contains at least one of silica and alumina particles, a water-absorbing binder, and a colorant; d. The second coating layer contains at least one of silica and alumina particles and a hydrophilic binder; e. The indicator means is attached to the diaper by intermittently joining the second paint layer to the inner surface of the back sheet through a non-oil type hot melt adhesive applied intermittently thereto. There is.
[0007]
【Example】
The details of the disposable diaper according to the present invention will be described with reference to the accompanying drawings.
[0008]
Pants-type diaper 1 shown in partial cutaway perspective view in FIG. 1, composed of a liquid-permeable topsheet 2, a liquid-impermeable back sheet 3, absorbent core 4 which is interposed between these two sheets 2, 3 Has been. Top- and backsheets 2, 3, portions extending from the peripheral edge of the core 4 are joined in a watertight manner. The diaper 1 is perforated front cylinder area (the front body) 6, the rear cylinder region (the rear body) 7 and a crotch region 8 positioned between these two cylinders regions 6, 7. Side edges of the respective two cylinders regions 6, 7 overlap each other with the topsheet 2 inside, are integrally joined at intermittently arranged by joints 10 in the vertical direction. The diaper 1 includes a waist opening 12 and the pair of leg-openings 13 are formed. A waist elastic member 15 and a leg elastic member 16 are attached to the peripheries of the openings 12 and 13 . These elastic members 15 and 16 are interposed between the front and back sheets 2 and 3 , and are stuck to at least one inner surface of the sheets 2 and 3 in an expanded state. For the top sheet 2, a non-woven fabric or an apertured plastic film is used . The back sheet 3 is obtained by stretching a light transmissive plastic film having a light transmittance of 20 to 80%, more preferably a plastic film containing inorganic particles such as titanium oxide, barium sulfate, and calcium carbonate. white to milky breathable, liquid-impervious film rate 30% to 70% is Ru is used Tei. The core 4 is a mixture is formed from a core portion 4A which is Fugata the hourglass, and the covering portion 4B made of tissue paper for which the fluff pulp and super-absorbent polymer particles. An indicator 18 for notifying the mother that urine has been excreted is attached to the front trunk region 6 . The indicator 18 is a strip-shaped sheet piece extending in the circumferential direction, and is interposed between the back sheet 3 and the core 4. When the indicator 18 gets wet with excreted urine, the illustrated floral pattern 19 printed on the indicator 18 becomes visible so that it can be seen through the back sheet 3. As a result, the mother can recognize that urination has occurred, and can know that the diaper 1 is in time for replacement.
[0009]
FIG. 2 is a partial end view taken along line II-II in FIG. In the figure, the indicator 18 is formed of a hydrophilic base sheet 21, a floral pattern 19 printed on the inner surface thereof, and a masking portion 22 printed so as to cover at least the floral pattern 19 on the outer surface thereof . Masking unit 22, Hanagara 19 when the diaper 1 is in a dry state so as not substantially visible from the outside side of the diaper 1, for concealing floral 19. The indicator 18 is a hot melt adhesive in which a masking portion 22 corresponding to the floral pattern 19 is intermittently applied so that at least a portion of the base sheet 21 on which the floral pattern 19 is printed is in close contact with the back sheet 3. 23 is joined to the inner surface of the back sheet 3. However, the band-shaped indicator 18 may not be joined to the back sheet 3 in the range of the length L at the end thereof. In the figure, the floral pattern 19 is in close contact with the core 4.
[0010]
The base sheet 21 constituting the indicator 18 is made of hydrophilic paper that has a basis weight of 15 to 40 g / m ² and can be printed. The floral pattern 19 is, for example, 5 to 20% by weight of a pigment having a color tone different from that of the base sheet 21 and the masking part 22, and light-scattering inorganic particles 5 to 35 such as silica (SiO ₂ ) and alumina (Al ₂ O ₃ ). wt%, 5-25 wt% hydrophilic acrylic binder, an ink or paint of an aqueous consisting of water 30 to 75 wt%, etc., are colored is obtained by printing or applied by suitable means to one side of the base sheet 21 The first paint layer. When the floral pattern 19 is in a dry state, the inorganic particles scatter light and become white, and in a wet state wet with urine , the scattering decreases, and the color of the floral pattern 19 becomes bright. The masking part 22 is, for example, a water-based ink or paint composed of 10 to 40% by weight of inorganic particles such as silica and alumina, 5 to 25% by weight of a hydrophilic acrylic binder, 40 to 85% by weight of water, and the like. 21 is a second paint layer obtained by printing or coating on the other-sided so as to cover the floral 19. When the masking portion 22 is in a dry state, the masking portion 22 scatters light and exhibits white or milky white, and makes it difficult to visually recognize the floral pattern 19 through the masking portion 22. When wet with urine, while the scattering becomes transparent decreases, because the color tone of the floral 19 different from the masking section 22 and the base sheet 21 is bright, the visibility of the floral 19 through the masking section 22 It becomes possible. At the time of such visual recognition, the base sheet 21 exhibits a concealing effect on the floral pattern 19 together with the masking portion 22 if it is in a dry state, and when wet, the effect is reduced and the floral pattern 19 is easily visible. To do.
[0011]
The back sheet 3 conceals the core 4 and usually exhibits white or milky white, but may have other color tones if necessary. If the indicator 18 inside the back sheet 3 is separated from the sheet 3, even if it gets wet and the floral pattern 19 becomes a vivid color, it is difficult to see through the back sheet 3. May be. However, since the indicator 18 is in close contact with the back sheet 3, there is no such fear. Moreover, when urine exists in the non-joining site | part 25 (refer FIG. 2) of the indicator 18 between the adhesive agents 23 apply | coated intermittently, and the back surface sheet 3, the visual recognition becomes still easier. The hot-melt adhesive 23 that joins the indicator 18 to the back sheet 3 sometimes penetrates into the masking part 22 and may become transparent in the same way as when the part 22 is wetted to lose its concealing effect. In order to eliminate such harmful effects, the adhesive 23 is intermittently applied at least at a portion corresponding to the floral pattern 19, and preferably applied so as not to exceed 70% of the area of the floral pattern 19. ing. Further, as the adhesive 23, a non-oil type hot-melt adhesive that does not contain an oil component and has no possibility of penetrating into the masking portion 22 is used.
[0012]
The indicator 18 joined to the back sheet 3 is in a state of free deformation without joining the range of the length L of the end part to the back sheet 3, and the possibility of contact with the core 4 is increased. Yes. Urine can permeate from the core 4 to the part of the floral pattern 19 joined to the back sheet 3 through this end. The length L of the end portion acting in this way is preferably 10 mm or more. Further, the indicator 18 and the covering portion 4B of the core 4 are intermittently joined so that the indicator 18 gets wet more reliably, or the back sheet 3 and the covering portion 4B are intermittently joined in the vicinity of the indicator 18. It may be.
[0013]
FIG. 3 is a view similar to FIG. This indicator 18 repeats undulations in its longitudinal direction and has a waveform having a top 30 and a bottom 31. The indicator 18 is in contact with the core 4 at the top 30 and is bonded to the back sheet 3 at the bottom 31 via the adhesive 23. The floral pattern 19 is on the bottom portion 31, and the masking portion 22 is formed on the entire outer surface of the base sheet 21. Urine penetrates the floral pattern 19 from the core 4 through the apex 30. Since the indicator 18 has a corrugated shape, it is possible to reliably contact the core 4 even when the back sheet 3 and the core 4 are separated from each other.
[0014]
4 and 5 are a view similar to FIG. 1 showing an aspect of the diaper 1 and an end view taken along the line V-V. In this diaper 1, a plurality of grooves 40 extending from the front waist region 6 to the crotch region 8 are formed on the inner surface 43 of the core portion 4A, and the grooves 40 and the indicator 18 intersect on the outer surface 44 side of the core portion 4A. Is in a state. The groove 40 is a portion where the core portion 4A is locally squeezed, and the bottom 40A of the groove 40 is in a state where the pulverized pulp is in close contact with each other and in a higher density than the remaining portion, and the inseam area 8 The urine excreted in the water can quickly diffuse the bottom portion 40A in the length direction to wet the indicator 18. In the core 4 composed of pulverized pulp or highly water-absorbing polymer particles, the body fluid is generally difficult to diffuse, but if there is a high-density bottom portion 40A as shown, the indicator 18 that is separated from the crotch region 8 also Easily gets wet and manifests.
[0015]
In this invention, it is preferable that the raw material used for the indicator 18 is hydrophilic so that it can easily get wet with urine. For example, the base sheet 21 uses pulp fibers or rayon fibers. The color tone of the base material sheet 21, the floral pattern 19, and the masking portion 22 of the indicator 18 can be selected so that the floral pattern 19 when wet becomes easy to see together with the color tone of the back sheet 3. In addition to the illustrated example, the masking portion 22 can be formed by applying ink or paint on the floral pattern 19 and in the vicinity thereof. In this case as well, the indicator 18 has the masking portion 22 formed. The existing surface is bonded to the back sheet 3. The base material sheet 21 is not limited to the belt shape as shown in the illustrated example, and can be formed in an appropriate shape. For example, if it is a rectangle, the non-joining area | region with respect to the back surface sheet 3 which has a width of 10 mm or more can be formed in the four periphery, and the possibility of a contact with the core 4 can be improved. The floral pattern 19 can be replaced with an appropriate pattern, or can be replaced with a paint layer formed on the entire surface of the base sheet 21. In the present invention, the material for forming the paint layer may be paint or ink, and a conventional coating technique including a printing technique can be used as its means. To these materials, a component for promoting the penetration of urine into the paint layer such as polyacryl ether can be added. The back sheet 3 made of a plastic film may be a cloth-like one having a non-woven fabric attached to the outer surface thereof.
[0016]
【The invention's effect】
In the disposable diaper according to the present invention, a first paint layer having an appropriate pattern that becomes bright when wetted on one side of a hydrophilic base sheet is formed, and the first paint layer in a dry state is formed on the other side of the base sheet. A second paint layer that conceals the color tone of the paint layer and becomes transparent in a wet state to reveal the first paint layer is used as an indicator, and this indicator is intermittently applied to the inner surface of the back sheet. because are bonded, excreted urine permeates the substrate sheet from the liquid-absorbent core, reach the first and second coating layer diffuses, the layers reliably wet, it can be vivid color . The indicator that is bonded to the back sheet is in a state where the edge or peripheral edge of the indicator can be freely deformed without bonding to the back sheet, or the corrugated undulation is in contact with the absorbent core. become. A groove with a high-density bottom formed by locally squeezing a liquid-absorbent core containing pulp fibers extends between the trunk area and the crotch area, and the indicator crosses the groove. In some diapers, even if the indicator is separated from the crotch region, it becomes wet and manifests as soon as urine is excreted. According to the present invention, since the indicator can be manufactured in a process different from the diaper production process, adoption of such an indicator does not hinder the productivity of the diaper.
[Brief description of the drawings]
FIG. 1 is a partially broken cross-sectional perspective view of a diaper.
FIG. 2 is an end view taken along the line II-II in FIG.
FIG. 3 is a view similar to FIG. 2 showing one embodiment of a diaper.
FIG. 4 is a view similar to FIG. 1 showing another embodiment of the diaper.
FIG. 5 is an end view taken along line VV in FIG. 4;
[Explanation of symbols]
1 disposable diaper 2 liquid- permeable top sheet 3 liquid- impermeable back sheet 4 liquid-absorbent core 18 indicator 19 floral pattern (first paint layer)
21 hydrophilic substrate sheet 22 masking part (second paint layer)
23 Hot melt adhesive 40A Bottom of groove

Claims (8)

If a liquid-absorbent core is interposed between the liquid-permeable top sheet and the liquid-impervious back sheet, and it becomes apparent from the outside that body fluid is excreted when it gets wet with body fluid in one of the front and rear side torso areas In disposable diapers having indicator means for tightening,
a. The back sheet is light transmissive;
b. The indicator means has a hydrophilic base sheet, a first paint layer having a color tone different from that of the base sheet and formed on one side of the base sheet , and formed on the other side of the base sheet is composed of a second coating layer capable to elicit the color tone becomes transparent in the wet state with which it substantially conceals the color of the first paint layer in a dry state is,
c. The first paint layer includes at least one of silica and alumina particles, a water-absorbing binder, and a colorant;
d. The second coating layer contains at least one of silica and alumina particles and a hydrophilic binder;
e. The indicator means is attached to the diaper by intermittently joining the second paint layer to the inner surface of the back sheet through a non-oil type hot melt adhesive applied intermittently thereto. The diaper characterized by the above. The diaper according to claim 1, wherein the back sheet is a plastic film having a light transmittance of 20 to 80%. The diaper according to claim 1 or 2, wherein in the indicator means, the first paint layer is intermittently disposed on the base material sheet . The diaper according to claim 1 or 2, wherein in the indicator means, the first paint layer and the second paint layer are intermittently disposed on the base sheet . The diaper according to any one of claims 1 to 4, wherein the base material sheet of the indicator means is freely deformable without joining a range of a peripheral width of 10 mm or more to the back sheet . The said base material sheet is a strip | belt piece long in one direction, Comprising: The length of 10 mm or more of both ends of this strip | belt piece is a deformation | transformation freedom, without joining to the said back surface sheet. Diapers. The base sheet draws a wave that undulates in one direction and is intermittently joined to the back sheet at the bottom of the wave, while the top of the wave can be separated from the back sheet and contact the core The diaper according to any one of claims 1 to 6, wherein the first paint layer is formed on the bottom of the wave . The core includes pulverized pulp, and a plurality of grooves in which the pulp is locally squeezed and the bottom portion is formed at a relatively high density extend between one of the front and rear side waist regions and the crotch region. The diaper according to any one of claims 1 to 7, wherein the indicator means provided in the trunk region and the groove are crossed in any of the trunk regions .

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