WO2019092810A1

WO2019092810A1 - Absorbent article

Info

Publication number: WO2019092810A1
Application number: PCT/JP2017/040268
Authority: WO
Inventors: 大和益井; 木村　真由美
Original assignee: 花王株式会社
Priority date: 2017-11-08
Filing date: 2017-11-08
Publication date: 2019-05-16
Also published as: JPWO2019092810A1; JP6452908B1; CN110022808B; TW201922188A; TWI761568B; CN110022808A

Abstract

An absorbent article provided with a front surface layer, a back surface layer, and an absorbing layer disposed between the front surface layer and the back surface layer, an intermediate fiber layer being provided between the front surface layer and the absorbing layer, wherein the absorbing layer, the front surface layer, and the intermediate fiber layer each contain a cooling sensation agent, and the content of the cooling sensation agent per unit area is greater in the intermediate fiber layer than in the absorbing layer, and greater in the intermediate fiber layer than in the front surface layer.

Description

Absorbent articles

The present invention relates to absorbent articles such as sanitary napkins, incontinence pads, diapers and the like.

In absorbent articles such as sanitary napkins, when the excretory fluid is large or when used for a long time, etc., mure and stickiness may occur and the wearer may feel uncomfortable. On the other hand, in the past, a technology has been proposed which attempts to improve the feeling of wearing except this unpleasant feeling by containing a cooling agent such as a refreshing agent in the absorbent article (for example, Patent Documents 1 and 2) ). The cooling agent volatilizes and stimulates TRPM8 and TRPA1 of the sensory nerve cells of the wearer's skin to change the receptor threshold, thereby giving a refreshing feeling.
Since the absorbent article described in Patent Document 1 addresses the problem that the cooling agent is consumed by excretion, the amount of the cooling sensation material in the area in contact with the excretory part of the wearer is larger than that in the other areas. doing. In addition, the absorbent articles described in

Patent Documents

2 and 3 address the problem of giving the wearer excessive irritation due to the refreshing agent, so in the planar direction of the articles, the absorbent articles described in the planar direction of the article are more The amount of freshener in other areas is increased.

JP, 2010-234031, A JP, 2010-234028, A JP, 2010-234027, A

The present invention is an absorbent article comprising a front surface layer, a back surface layer, and an absorption layer disposed between the front surface layer and the back surface layer, and an intermediate fiber layer between the front surface layer and the absorption layer. The absorbent layer, the surface layer and the intermediate fiber layer each contain a cooling agent, and the content per unit area of the cooling agent is larger in the intermediate fiber layer than in the absorption layer, and The absorbent article is provided with the intermediate fiber layer more than the surface layer.

The above and other features and advantages of the present invention will become more apparent from the following description with reference to the accompanying drawings as appropriate.

BRIEF DESCRIPTION OF THE DRAWINGS It is a partially notched perspective view shown typically from the skin contact surface side in the state which expand | extended the sanitary napkin as one preferable embodiment of the absorbent article in this invention. FIG. 2 is a cross-sectional view schematically showing a cross section taken along line II-II of the sanitary napkin shown in FIG. It is sectional drawing which shows typically the absorption layer in this embodiment, (A) is sectional drawing of the vertical direction, (B) is sectional drawing of the width direction. It is sectional drawing which shows typically the aspect in which the absorption layer in this embodiment has a high basic weight part with a back surface layer and the adhesion part, (A) is sectional drawing of the vertical direction, (B) is a width direction. FIG. FIG. 3 is a cross-sectional view equivalent to FIG. 2 showing an aspect in which the absorbent layer has a laminated structure of absorbent sheets. (A) to (D) are cross-sectional views showing other preferred examples of the folded structure of the central absorbent sheet. It is a partially cutaway perspective view equivalent to FIG. 1 which shows typically the aspect which has a communicating part the sanitary napkin of this embodiment. Fig. 8 is a cross-sectional view schematically showing a cross section taken along line VIII-VIII of the sanitary napkin shown in Fig. 7. It is a top view of the absorption layer which the sanitary napkin shown in FIG. 7 has. It is sectional drawing which shows typically another preferable aspect of an absorption layer, (A) is sectional drawing of an aspect which has a convex part and recessed part space in the surface layer side, (B) is a convex part in the back layer side. It is sectional drawing of the aspect which has and recessed part space.

Detailed Description of the Invention

The present invention relates to an absorbent article capable of effectively maintaining a sufficiently cool effect on a wearer's skin for a sufficiently long time.

In an absorbent article containing a cooling agent, the skin of the wearer's so-called delicate area (the excretory part) has a small number of horny layers, and thus is susceptible to a strong sensation of cold. In addition, in the liquid receiving area of the napkin corresponding to the delicate area, the cold sensation is likely to be excessively effective due to the excretion.
As in the case of the absorbent article described in Patent Document 1, simply increasing the amount of the cooling agent in the area facing the wearer's excretory part (the liquid receiving area) may cause pain and discomfort, It may damage the feeling of wearing. On the other hand, as in the case of the absorbent articles described in

Patent Documents

2 and 3, when a large amount of the cooling agent is disposed outside the area facing the wearer's excretory part (the liquid receiving area), sufficient cooling sensation in the easily entangled part It will be difficult to sustain the effect.

On the other hand, the absorbent article according to the present invention can maintain a sufficiently good cooling sensation effect on the skin of the wearer sufficiently long and effectively.

Hereinafter, a sanitary napkin (hereinafter also referred to as a napkin) 10 as a preferred embodiment of the absorbent article according to the present invention will be described with reference to the drawings.
In the present invention, unless otherwise stated, the side in contact with the human body is referred to as the skin surface side or the skin contact surface side or the surface side, and the opposite side is the non-skin surface side or the non-skin contact surface side or the back surface side It is said. These are used also as a term which shows relative physical relationship in member composition of an absorptive article also about a member which does not have a field which contacts a human body. Moreover, the direction which is located in the front side of a human body at the time of wear is called front, and the direction which is located in the rear side is called back. The normal direction of the front surface or the back surface of the absorbent article is referred to as the thickness direction.

As shown in FIGS. 1 and 2, the napkin 10 is disposed between the surface layer 1 on the skin contact surface side, the back surface layer 2 on the non-skin contact surface side, and the surface layer 1 and the back surface layer 2. And a liquid retaining absorbent layer 3. Furthermore, an intermediate fiber layer 4 having liquid diffusibility is disposed between the surface layer 1 and the absorbent layer 3. The surface layer 1 has liquid permeability that sends the liquid to the absorbent layer 3, and the back surface layer 2 has leak resistance to the liquid in the absorbent layer 3. The surface layer 1 and the back surface layer 2 have a size that extends outward of the outer edge of the absorption layer 3 while covering both surfaces of the absorption layer 3. The intermediate fiber layer 4 has an effect of spreading the waste fluid permeated from the surface layer 1 in the planar direction to widen the absorption area on the skin surface side of the absorbent layer 3.
In the present embodiment, the side sheets 5 are laminated on both sides of the skin contact surface side of the surface layer 1. The side sheet 5 and the back surface layer 2 extend outward in the width direction of the absorbent layer 3 to form a wing portion 6 which is a fixing means to clothes or the like. The non-skin contact surface side of the wing portion 6 and the back surface layer 2 has an adhesive portion 7 for fixing the napkin 10 to clothes. In the laminated structure of the sheet, the outer peripheral edge of the napkin 10 is an outer peripheral seal portion 9 joined without interposing the absorbing layer 3.

The napkin 10 may include other components, and may have a form without the side sheet 5. Furthermore, it may have a leak-proof groove squeezed from the surface layer 1 to the absorbent layer 3, a plurality of embossments on the surface layer 1, and the like. In addition, the side sheet 5 may be left at the free end inward of both sides of the surface layer 1 while being bonded to the surface layer 1, and an elastic member or the like may be provided at the free end to prevent A leak cuff may be configured.

The napkin 10 has a longitudinally long shape having a longitudinal direction (Y direction) and a width direction (X direction) orthogonal to the longitudinal direction in a plan view. Moreover, the surface layer 1, the back surface layer 2, and the absorption layer 3 are longitudinally long shapes like the napkin 10. The longitudinal direction corresponds to the direction connecting the wearer's ventral side, crotch and dorsal side when the napkin 10 is worn. The width direction corresponds to the direction in which the left and right feet in the crotch of the wearer are connected. In the present specification, the longitudinal direction (Y direction) and the width direction (X direction) indicate the direction in plan view of the napkin 10 and at the same time indicate the direction in plan view of the surface layer 1, the back layer 2 and the absorbent layer 3 .

The napkin 10 has, in the longitudinal direction, an intermediate portion C including a region corresponding to the wearer's excretory portion, and a front portion F and a rear portion R located on both end sides thereof. The front part F is disposed to face the lower abdomen of the wearer, and the rear part R is disposed to face the buttocks side of the wearer.
In the middle part C, there is a liquid receiving area C1 facing the excretory part and directly receiving the excrement fluid at the central part in the width direction. The "width direction central portion" where the liquid receiving area C1 is, as shown in FIG. 1, means a range of a predetermined width extending laterally from the center line L in the width direction, and is inside the both widthwise end edges 39 of the absorption layer. Say the part of the range. Specifically, it is a region that spreads laterally from the center line L in the width direction of the napkin 10 and is a portion in the range of 40% to 60% of the width of the absorbent layer. The middle part C, the liquid receiving area C1, the front part F and the rear part R indicate the divisions in the napkin 10, and at the same time, in the surface layer 1, the back layer 2, the absorbent layer 3 and the intermediate fiber layer 4 corresponding thereto. It also shows the classification.

The division positions of the middle portion C, the front portion F and the rear portion R may be appropriately set according to the length of the absorbent article set according to the purpose of use and the like. In the case of providing a wing portion that is bent and fixed to the crotch portion of the shorts, a region along the longitudinal direction in which the wing portion is present is the middle portion C. The napkin 10 of the present embodiment shows an example of a shape set for daytime use, etc., and the length in the longitudinal direction is equally divided into three to set the front part F, middle part C and rear part R In the case of a day napkin without cages and wings, the middle part follows this setting. In general, regardless of the shape of the napkin 10, the middle portion C can be set as a portion located at a certain distance from the front portion F. Furthermore, for adult or infant diapers and the like, and for urine collection pads and the like, the length in the longitudinal direction is equally divided into three, and the front part F, middle part C and rear part R are set.

The napkin 10 contains a cooling agent. The cooling agent stimulates the temperature receptor on the wearer's skin and / or mucosal surface to make the wearer feel cool and refreshing without changing the temperature on the skin and / or mucosal surface. It is an agent that can
Below, the layer and content which contain the cooling agent in the napkin 10 are demonstrated.

The cooling agent is contained in the surface layer 1, the absorbent layer 3 and the intermediate fiber layer 4 of the napkin 10. The content per unit area of the cooling agent (hereinafter, also simply referred to as “the amount of cooling agent”) is larger in the intermediate fiber layer 4 than in the absorbent layer 3 and in the intermediate fiber layer 4 than in the surface layer 1.

Thus, in the napkin 10, the intermediate fiber layer 4 preferentially contains a cooling agent, and the content of the cooling agent in the surface layer 1 is suppressed. As a result, the amount of cooling agent released from the surface layer 1 close to the skin is suppressed to an appropriate amount, and the intermediate fiber layer 4 covered by the surface layer 1 and the absorbing layer 3 of the lower layer further contain volatile components of the cooling agent. It is released to the skin with a time lag. As a result, it is possible to prevent the concentration of the volatile component of the cooling agent reaching the skin from becoming too high, and to suppress excessive stimulation due to the feeling of cold on the skin.

The amount of the cooling agent is preferably the intermediate fiber layer 4, the absorbent layer 3, and the surface layer 1 in descending order of the amount. That is, the amount of cooling agent of the intermediate fiber layer 4 can be larger than that of the absorbing layer 3, and the amount of cooling agent of the absorbing layer 3 can be larger than that of the surface layer 1. Thus, it is preferable that the layer closest to the skin contains the least amount of cooling agent among the three layers laminated, and the intermediate fiber layer 4 and the absorbent layer 3 contain a relatively large amount of cooling agent. . By increasing the content of the cooling agent in the intermediate fiber layer 4 which is a region closer to the surface layer 1 in the thickness direction than the absorption layer 3, it is possible to quickly feel an appropriate cooling sensation effect. Furthermore, by setting the distribution of the content of the cooling agent as described above, the content of the cooling agent is increased in a region separated from the surface layer 1 in the thickness direction, particularly in the absorption layer 3, and a good cooling effect is obtained. Can be effectively maintained for a sufficiently long time.

Content of the cooling agent per unit area in the intermediate fiber layer 4 as an embodiment in which the amount of the cooling agent described above is larger in the intermediate fiber layer 4 than in the absorbing layer 3 and in the intermediate fiber layer 4 than the surface layer 1 The mass ratio (N1 / N2) to the content (N2) per unit area in the absorbent layer 3 of N1) is 1.05 or more, and the content per unit area of the cooling agent in the intermediate fiber layer 4 (N1) It is preferable to make mass ratio (N1 / N3) with respect to content (N3) per unit area in surface layer 1 of N1) or more into 1.17 or more.

The mass ratio (N1 / N2) of the content per unit area (N1) of the cooling agent in the intermediate fiber layer 4 to the content (N2) per unit area of the cooling agent in the absorbent layer 3 is an appropriate amount of cold From the viewpoint of quickly imparting an effect, 1.05 or more is preferable, 1.10 or more is more preferable, and 1.20 or more is still more preferable. The mass ratio (N1 / N2) is preferably 3.00 or less, more preferably 2.50 or less, and still more preferably 2.30 or less, from the viewpoint of imparting a proper cooling sensation effect.

The mass ratio (N1 / N3) of the content per unit area (N1) of the cooling agent in the intermediate fiber layer 4 to the content (N3) per unit area of the cooling agent in the surface layer 1 is From the viewpoint of providing a moderate cooling effect, 1.17 or more is preferable, 1.33 or more is more preferable, and 1.53 or more is still more preferable. Moreover, from a viewpoint of suppressing the stimulus by the excessive cool feeling to a wearer's skin, 20 or less are preferable, 10 or less are more preferable, and the said mass ratio (N1 / N3) is still more preferable 6.67 or less.

The mass ratio (N2 / N3) of the content (N2) per unit area of the cooling agent in the absorption layer 3 to the content (N3) per unit area of the cooling agent in the surface layer 1 is the cooling effect From the viewpoint of sustainability, 1.11 or more is preferable, 1.21 or more is more preferable, and 1.28 or more is still more preferable. The mass ratio (N2 / N3) is preferably equal to or less than 6.67, more preferably equal to or less than 4.00, and still more preferably equal to or less than 2.90, from the viewpoint of imparting a proper cooling sensation effect.

The cooling agent is distributed to each layer consisting of the surface layer 1, the absorbent layer 3 and the intermediate fiber layer 4 and contained with the above concentration difference, so even if the amount is increased, excessive irritation to the skin of the wearer is It can be suppressed.

Although the content per unit area of the cooling agent in the surface layer 1, the intermediate fiber layer 4 and the absorbing layer 3 can not be uniquely determined by the type of the article etc., for example, it contains menthyl lactate as a cooling agent. Taking the case of a napkin for daytime as an example, it is as follows.
The content per unit area of the cooling agent in the surface layer 1 is preferably 0.01 g / m ² or more, more preferably 0.03 g / m ² or more, from the viewpoint of a moderate cooling effect in the initial stage of wearing. 05 g / m ² or more is more preferable. Further, the content per unit area of the cooling agent in the surface layer 1 is preferably 0.5 g / m ² or less, more preferably 0.4 g / m ² or less, from the viewpoint of imparting an appropriate cooling sensation effect. Preferably, 0.3 g / m ² or less is more preferable.
Content per unit area of the cooling agent in the absorption layer 3, from the viewpoint of sustained cooling effect, 0.03 g / ^{m 2} or more preferably, 0.05 g / ^{m 2} or more, more preferably, 0.07 g It is more preferable to use / m ² or more. The content per unit area of the cooling agent in the absorption layer 3, from the viewpoint of imparting moderate cooling effect, preferably 1.5 g / m ² or less, more preferably 1.3 g / m ^2, More preferably, it is 1.1 g / m ² or less.
Content per unit area of the cooling agent in the intermediate fiber layer 4, from the viewpoint of feel quickly moderate cooling effect, 0.05 g / ^{m 2} or more preferably, 0.07 g / ^{m 2} or more, and 0.1 g / m ² or more is more preferable. The content per unit area of the cooling agent in the intermediate fiber layer 4, from the viewpoint of imparting moderate cooling effect, preferably 2.0 g / m ² or less, more preferably 1.5 g / m ² or less 1.0 g / m ² or less is more preferable. The intermediate fiber layer 4 is intermediate between the surface layer 1 and the absorbent layer 3, and the volatile component of the cooling agent contained in the intermediate fiber layer 4 is appropriately transferred to the skin surface side through the surface layer 1, At the same time, the volatile component of the cooling agent contained in the absorbing layer 3 has a buffering effect of suppressing excessive migration to the skin surface side, so that a reasonable cooling sensation effect can be given to the user for a long time even if the amount is increased. It becomes.

(How to measure the amount of cooling agent per unit area)
The cooling agent can be extracted with a solvent from the target member or target site of the absorbent article, and the extraction solution can be analyzed by gas chromatography (GC). The measurement is performed with a flame ionization detector (FID) attached to a gas chromatograph, and can be measured, for example, by 7890A manufactured by Agilent technologies. The relationship between the concentration of the cooling agent and the peak area is calibrated in advance, and quantitative work is performed based on the calibration curve.
The case where the cooling agent contains menthyl lactate and / or menthol is described as an example. Menthyl lactate and / or menthol is extracted from the target member or target site using methanol as a solvent. Using methanol as a solvent, prepare in advance 3 to 5 steps of menthyl lactate solution and / or menthol solution with different concentrations, calculate peak areas of each concentration from the chromatogram of GC, and use n-pentyl alcohol as a standard sample A standard curve is plotted where the peak area is plotted against the concentration of the standard sample. By analyzing the extract under the same conditions as the analysis for which the calibration curve was prepared, the peak area obtained is applied to the calibration curve to calculate the amount of menthyl lactate and / or the amount of menthol. The amount of cooling agent per unit area (cooling agent basis weight) can be determined by dividing the amount of menthyl lactate and / or menthol obtained by the area of the product site collected in advance. Also, the amount of cooling agent obtained per 100 mm of product length is determined by dividing the obtained amount of menthyl lactate and / or amount of menthol by the longitudinal length (mm) of the absorbent article and multiplying by 100. Can.
In order to know the amount of cooling agent for each component or part of the product, it is possible to analyze by decomposing the product in a chamber at 5 ° C. and taking out the material part to be measured.

In the napkin 10 having the content distribution of the cooling agent as described above, it is preferable that the volatile component of the cooling agent contained in the intermediate fiber layer 4 and the absorbent layer 3 can smoothly transfer to the skin even if there is excretion. . From this viewpoint, it is preferable that the liquid diffusibility of the surface layer 1 is smaller than the liquid diffusivity of the intermediate fiber layer 4 and the absorbent layer 3. Thereby, the diffusion area of the excretory fluid in the surface layer 1 in the plane direction becomes relatively smaller than that of the intermediate fiber layer 4 and the absorbent layer 3, and the range that prevents the migration of the volatile component of the cooling agent by the excretory fluid Becomes smaller. Therefore, even while the napkin 10 is receiving waste fluid (for example, multiple excretions), the volatile component of the cooling agent which rises with a time difference from the intermediate fiber layer 4 and the absorbent layer 3 smoothly reaches the skin. Cheap. As a result, a moderate cool sensation effect can be provided longer. In this case, the excretory fluid is transmitted to the non-skin surface side in the range around the liquid receiving area C1 of the surface layer 1. By this, at the time of receiving the excretory fluid, it is possible to moderate the stimulation by the cold feeling to the so-called delicate area (the excretory part) of the corresponding wearer. In addition, since the excretory fluid is rapidly transmitted from the surface layer 1 to the non-skin side layer due to the difference in the diffusivity described above, the discomfort of the skin due to wetting is avoided, and the excretory fluid is the evaporation route of the cooling agent. Moderate coolness can be maintained without blocking the

The intermediate fiber layer 4 is preferably a non-woven fabric containing thermoplastic fibers from the viewpoint of enhancing the liquid diffusibility. This suppresses the exudation of the cooling agent to the non-skin surface side on the skin side 3A of the intermediate fiber layer 4 and the absorbent layer 3, and the cooling sensation effect on the skin is likely to be maintained longer.

The above-mentioned liquid diffusivity is shown by the liquid diffusion area by the following measuring method.
Wear a napkin on the dynamic walking model. 3 g of simulated blood adjusted to a viscosity of 8 cps is injected at a flow rate of 0.2 g / s and walked for 3 minutes while the dynamic walking model is walking at a walking speed of 100 steps / min, and then the flow rate is 0.2 g / s Inject 3 g again. Immediately after the completion of the second equine blood injection, the napkin is disassembled, and the liquid diffusion area in the surface layer, the intermediate fiber layer, and the absorbent layer (skin surface side) is measured. For measurement of the liquid diffusion area, the spread of simulated blood is drawn using a transparent film such as KOKUYO OHP film, and image data is created with a scanner (model CANOScan 8800F manufactured by CANON), and then image analysis software (nexus nexus) Calculate the area according to the number of pixels in New Qube). The unit cps of viscosity is converted by 1 cps = 1 × 10 ⁻³ Pa · s. In addition, the simulated blood has a viscosity of 8 mPa · s at 25 ° C when measured using a B-type viscometer (Model TVB-10M, manufactured by Toki Sangyo Co., Ltd., measurement conditions: rotor No. 19, 30 rpm, 60 seconds) The ratio of blood cells to plasma of defibrinated horse blood (manufactured by Japan Biotest Laboratories Co., Ltd.) was adjusted.

The liquid diffusion area of the surface layer 1 is preferably 90% or less, more preferably 80% or less, with respect to the liquid diffusion area of the intermediate fiber layer 4. The liquid diffusion area of the surface layer 1 is preferably 80% or less, more preferably 70% or less, with respect to the liquid diffusion area of the absorbing layer 3.

Moreover, it is preferable that the average inter-fiber distance (D1) in the surface layer 1 is larger (D1> D4) than the average inter-fiber distance (D4) in the intermediate fiber layer 4. By this, the volatile component of the cooling agent contained in the intermediate fiber layer 4 is easily shifted to the skin surface side with a time difference while being suppressed to some extent by the coating with the surface layer 1.
The average inter-fiber distance (D1) in the surface layer 1 is from the viewpoint of effectively transferring the volatile component of the cooling agent contained in the intermediate fiber layer 4 and the absorption layer 3 to the skin surface side. 105% or more is preferable with respect to average fiber distance (D4), 115% or more is more preferable, 130% or more is still more preferable. Further, the average inter-fiber distance (D1) in the surface layer 1 is the average in the intermediate fiber layer 4 from the viewpoint of appropriately shifting the volatile component of the cooling agent contained in the intermediate fiber layer 4 and the absorbent layer 3 to the skin surface side. 400% or less is preferable with respect to the distance between fibers (D4), 300% or less is more preferable, and 200% or less is still more preferable.

(Measurement method of average fiber distance)
The average inter-fiber distance is determined by measuring the thickness of the nonwoven fabric to be measured as follows and applying the following equation (2).
First, the nonwoven fabric to be measured is cut in the longitudinal direction of 50 mm × the width direction of 50 mm to prepare a cut piece of the nonwoven fabric. If a cut piece of this size can not be obtained, such as when the nonwoven fabric to be measured is incorporated into an absorbent article, the cut piece is manufactured by cutting to the maximum size that can be obtained.
The thickness of this cut piece is measured at 49 Pa pressure. The measurement environment is a temperature of 20 ± 2 ° C., a relative humidity of 65 ± 5%, and a measuring instrument is a microscope (VHX-1000, manufactured by Keyence Corporation). First, an enlarged photograph of the cross section of the non-woven fabric is obtained. Photographs of known dimensions are simultaneously copied in the enlarged picture. The scale is fitted to the enlarged photograph of the non-woven fabric cross section, and the thickness of the cut piece is measured. The above operation is performed three times, and the average value of three times is taken as the thickness [mm] of the non-woven fabric in a dry state. In the case of a laminate, the boundary is determined from the fiber diameter to calculate the thickness.
Next, the inter-fiber distance of the fibers constituting the nonwoven fabric to be measured is determined by the equation based on Wrotnowski's assumption shown below. An equation based on Wrotnowski's assumption is generally used to determine the inter-fiber distance of the fibers constituting the non-woven fabric. According to the equation based on Wrotnowski's assumption, the inter-fiber distance A (μm) is the thickness h (mm) of the non-woven fabric, the basis weight e (g / m ² ), the fiber diameter d (μm) of the fibers constituting the non-woven fabric, It is calculated | required by following Numerical formula (2) by fiber density rho (g / cm < ³ >). In addition, when it has unevenness, it calculates using nonwoven fabric thickness h (mm) of a convex part as a representative value.
As for the fiber diameter d (μm), ten fiber cross sections of the cut fiber are measured using a scanning electron microscope (DSC 6200 manufactured by Seiko Instruments Inc.), and the average value is defined as the fiber diameter.
The fiber density ρ (g / cm ³ ) is measured using a density gradient tube according to the measurement method of the density gradient tube method described in JIS L 1015 chemical fiber staple test method.
The basis weight e (g / m ² ) is obtained by cutting the nonwoven fabric to be measured into a predetermined size (eg, 0.12 m × 0.06 m), and after mass measurement, “the area determined from mass ̃predetermined size = Basic weight (g / m ² ) is calculated by the formula to determine the basis weight.

In the absorption layer 3, the content per unit area of the cooling agent is preferably larger in the skin side 3A than in the non-skin side 3B of the absorption layer 3 (see FIGS. 3A and 3B). ). Thereby, the cooling agent in the absorbent layer 3 is volatilized and it becomes easy for the wearer to reach the skin to the wearer, and the wearer quickly feels cold when worn, and imparts an immediate effect on how to feel cold. it can.

The skin side surface 3A in the absorbing layer 3 is a portion divided according to the following definitions (1) to (3) according to the structure of the absorbing layer 3.
(1) When the absorbent layer 3 is a laminate of a plurality of absorbent sheets, the portion of the absorbent sheet located closest to the skin side is taken as the skin side surface.
(2) In the case where the absorbent layer 3 is formed by covering an absorbent core obtained by stacking liquid absorbent materials such as pulp with a core wrap sheet, the portion of the core wrap sheet located closest to the skin side is taken as the skin side.
(3) When the absorbent layer 3 is the one in which the absorbent core is exposed, a portion up to a thickness of 1 mm from the outermost skin side of the absorbent core is taken as the skin side surface.
Based on this definition, the content per unit area of the cooling agent (the amount of cooling agent) in the “skin side” is the content in the following portion. That is, in the case of the above (1), it is the amount of the cooling agent contained in the absorbent sheet located closest to the skin. In the case of (2), it is the amount of the cooling agent contained in the core wrap sheet located closest to the skin. In the case of (3), it is the amount of the cooling agent contained in a portion from the surface layer portion closest to the skin to a thickness of 1 mm.

Further, the non-skin side 3B in the absorbing layer 3 is a portion divided according to the following definitions (1) to (3) according to the structure of the absorbing layer.
(1) When the absorbent layer 3 is a laminate of a plurality of absorbent sheets, the portion of the absorbent sheet located closest to the non-skin side is taken as the non-skin side.
(2) In the case where the absorbent layer 3 is an absorbent core obtained by stacking liquid absorbent materials such as pulp and covered with a core wrap sheet, the portion of the core wrap sheet located closest to the non-skin side is the non-skin side. Do.
(3) When the absorbent layer 3 is the one in which the absorbent core is exposed, a portion up to a thickness of 1 mm from the surface layer portion on the most non-skin side of the absorbent core is taken as the non-skin side.
Based on this definition, the content per unit area of the cooling agent (the amount of cooling agent) in the “non-skin side” is the content in the following portion. That is, in the case of the above (1), it is the amount of the cooling agent contained in the absorbent sheet located closest to the non-skin side. In the case of the above (2), it is the amount of the cooling agent contained in the core wrap sheet located closest to the non-skin side. In the case of (3), it is the amount of the cooling agent contained in a portion from the surface layer portion on the non-skin side to the thickness of 1 mm.

Distribution of the content per unit area of the cooling agent in the surface layer 1, the intermediate fiber layer 4 and the absorbing layer 3 described above, a unit of the cooling agent between the skin side 3A and the non-skin side 3B of the absorbing layer 3 The distribution of content per area can be formed by various methods.
For example, 1) A method of producing the napkin 10 using the surface layer 1 containing the predetermined amount of cooling agent, the intermediate fiber layer 4 and the absorbent layer 3 or a sprinkler etc. in the process of producing the napkin 10 A method of designing the cooling agent content in advance in each member, such as a method of applying the cooling agent to each member; 2) after blending the cooling agent only on the skin side 3A of the absorbent layer 3 Method of placing the intermediate fiber layer 4 and the surface layer 1 after leaving it to stand for a predetermined time in a predetermined temperature environment, and transferring the cooling agent to these layers; 3) a cooling agent only in the absorption layer 3 After application, a method of forming a predetermined content distribution by holding the cooling agent in the intermediate fiber layer 4 by using the intermediate fiber layer 4 having higher adsorptivity and retention of the cooling agent than the absorbent layer 3, etc. Can be mentioned.

For example, in the above 2), it is assumed that the cooling agent distribution of the present invention is realized by the following mechanism. The movement of the cooling agent in the absorption layer 3 is in an equilibrium state by the standing step after the cooling agent is applied only to the skin side 3A of the absorption layer 3. In the standing step, the airtightness is high (for example, the entire surface of the absorbent layer 3 is covered with an airtight container, etc.) so that the cooling agent does not easily volatilize to the outside. Although a concentration gradient of the cooling agent occurs on the skin side 3A and the non-skin side 3B of the absorbing layer 3, the cooling agent is originally added only to the skin side 3A of the absorbing layer 3, and both

sides

3A and 3B have the same environment. In order to be placed, it is presumed that movement to one surface side to the extreme is suppressed. Then, an absorbent article is manufactured by combining the absorbent layer in a balanced state of the cooling agent with other members, whereby an appropriate amount of cooling agent is transferred to each member in contact with the absorbent layer 3.
On the other hand, in the manufacturing method and structure in which a large amount of cooling agent is disposed in the member on the surface layer 1 side and the excess cooling agent is easily moved to the surface layer 1, a large amount of cooling agent is present in the surface layer 1 It becomes easy to do. For example, as in the comparative production example described later, when the intermediate fiber layer 4 is provided with a cooling agent, or when the intermediate fiber layer 4 is provided in the absorbent layer 3 immediately after the application of the cooling agent, the cooling agent is an intermediate fiber layer It is easy to cause movement to the surface layer 1 adjacent to 4 and this, and the cooling agent moves from the intermediate fiber layer 4 to the surface layer 1 at a stretch so as to supplement the cooling agent volatilized from the surface layer 1. The amount of the cooling agent is considered to be equal to or higher than that of the intermediate fiber layer 4.
However, according to the method of 2) described above, since the cooling agent is spread over the entire absorbent layer 3 before arranging the members such as the intermediate fiber layer 4 and the like, the excess cooling agent is added to the intermediate fiber layer 4 Is suppressed at once, and the cooling agent is easily supplied gently to the skin side 3A of the absorbent layer 3 where the concentration of the cooling agent is lowered by the movement to the intermediate fiber layer 4. And since intermediate fiber layer 4 and surface layer 1 exist on skin side 3A of absorption layer 3, some cooling agents are surface layers, while intermediate fiber layer 4 holds a cooling agent temporarily. It will be supplied to 1. Then, when the cooling agent is volatilized from the surface layer 1, the cooling agent is replenished from the intermediate fiber layer 4. For this reason, it is considered that the amount of cooling agent of the intermediate fiber layer 4 is larger than that of the surface layer 1 and the absorbent layer 3.

Moreover, in 3) mentioned above, it is mentioned as an embodiment, for example, using the sheet whose basis weight is larger than the surface layer 1 as the intermediate fiber layer 4, or the sheet whose thickness is large. In addition, in the case of using a cooling agent with low hydrophilicity (for example, menthol, menthyl lactate, etc.), making the hydrophilicity of the intermediate fiber layer 4 lower than that of the surface layer 1 can also be mentioned as an example.
And it is considered that combining the above 2) and 3) is more effective in achieving the effects of the present invention.

The above distribution can also be formed, for example, by suitably setting the arrangement position of the application part of the cooling agent solution, as described above. The cooling agent solution is a coating liquid in which a cooling agent and a solvent are mixed, and is a liquid used when being contained in the napkin 10. The application part of the cooling agent solution is a part initially contained in the manufacturing process. As the solvent, various ones commonly used can be adopted. For example, dipropylene glycol and the like can be mentioned.

As shown in FIGS. 4A and 4B, the absorbent layer 3 preferably includes a high basis weight portion 33 in the middle portion C of the napkin 10, in which the absorbent layer basis weight is higher than that of the surroundings. In particular, the high basis weight portion 33 is preferably disposed in the liquid receiving region C1 of the central portion in the width direction among the middle portion C, and is more preferably disposed in a predetermined range including the liquid receiving region C1. The high basis weight portion 33 can be formed by various methods depending on the aspect of the absorbent layer 3. For example, in the case where the absorbent layer 3 has an absorbent core obtained by stacking liquid absorbent materials such as pulp, the high basis weight portion 33 can be formed by increasing the amount of piled liquid absorbent material over the surroundings. . Moreover, when it is a laminated body of the absorptive sheet mentioned later, the high basis weight part 33 can be formed by increasing the number of sheets of an absorptive sheet rather than circumference | surroundings.

The high basis weight portion 33 is bulkier than the other portions of the absorbent layer 3 and is relatively easy to hold the cooling agent. Thereby, the transfer of the cooling agent to the non-skin surface side of the napkin 10 due to the passage of time can be suppressed, and the amount of transfer of the cooling agent volatile component to the skin of the wearer can be secured. In addition, the bulky high basis weight part can relatively suppress the excessive diffusion of the volatile component of the cooling agent. Thereby, in the middle part C corresponding to the so-called delicate area (the excretory part) of the wearer, it is possible to suppress the stimulation due to the excessive cold sensation and to provide a moderate cool sensation effect for a long time.

It is preferable that the adhesion part 7 for clothing fixation is arrange | positioned in the part which overlaps with the high basis weight part 33 of the absorption layer 3 in planar view of the non-skin side of the back surface layer 2 (FIG. 4 (A) and (B) reference). In the high basis weight portion 33, the transition of the cooling agent to the non-skin surface side of the high basis weight portion 33 is small, and the cooling agent contained in the high basis weight portion 33 hardly bleeds from the back surface layer 2. By disposing the adhesive portion 7 on the non-skin surface side of the back surface layer 2 and overlapping the high basis weight portion 33 in plan view, it is possible to suppress the decrease in the adhesive strength of the adhesive portion 7 by the cooling agent. In FIG. 4A and 4B, the adhesion part 7 is made into the strip | belt shape extended in the width direction, and the aspect by which a plurality are intermittently arranged longitudinally is shown. In this embodiment, some of the band-shaped adhesive portions 7 are disposed in a portion overlapping with the high basis weight portion 33 in plan view. The arrangement of the adhesive portion 7 is not limited to this aspect, and may be any pattern as long as the adhesive portion 7 is disposed in a portion overlapping the high basis weight portion 33. For example, the adhesive portion 7 may be disposed in a predetermined range including a portion overlapping the high basis weight portion 33, or may be disposed on the entire non-skin side surface of the back surface layer 2. Moreover, the adhesion part 7 may be divided | segmented into plurality with respect to the non-skin side of the back surface layer 2, may be intermittently arrange | positioned, and may be continuously distribute | arranged to one side.

The absorbent layer 3 preferably has a laminated structure of absorbent sheets. By this, it becomes easy to control suitably the transfer amount to the thickness direction of a cooling agent inside the absorption layer 3. FIG. That is, the cooling agent can be more easily transferred in the plane direction in the same layer than in the thickness direction through the interface between the layers, and the amount of the cooling agent in the layers can be appropriately suppressed. As a result, the amount of cooling agent on the non-skin side of the absorbent layer 3 can be prevented from becoming excessive, and the cooling agent can be held as close to the skin side of the absorbent layer 3 as possible. In addition, the volatile component of the cooling agent can be temporarily stored between the layers in the absorption layer 3 to impart a moderate cooling effect to the skin for a longer time.
In addition, the above-mentioned high basis weight portion 33 is compared with the front and rear thereof (the portions of the absorbent layer 3 other than the high basis weight portion 33 located forward and backward than the high basis weight portion 33 in the longitudinal direction of the absorbent layer 3). Preferably, the number of laminated absorbent sheets is increased. Thereby, temporary storage of the volatile component of the cooling agent mentioned above occurs more easily, and it is possible to give a longer cool feeling as the stimulation on the so-called delicate area (the excretory part) of the wearer is suppressed.

The absorbent sheet is a thin sheet having a thickness in which a superabsorbent polymer material is sandwiched and fixed between two sheet-like fiber layers made of hydrophilic fibers. In forming the absorbent sheet, the superabsorbent polymer can be integrated by using the adhesive force which is developed by wetting, the binder added separately, and the binder such as the adhesive fiber. The preparation can be performed by various methods commonly used, and may be either wet or dry. The absorbent sheet has high absorbency, which is difficult to cause gel blocking because the highly water-absorptive polymer material is dispersedly disposed in the planar direction of the sheet while the thickness is suppressed to 3.0 mm or less. For example, those described in paragraphs [0019] to [0131] of JP-A-8-246395 can be mentioned.

When the absorbent layer 3 has a laminated structure of absorbent sheets, it preferably has a laminated structure as shown in FIG.
The absorbent layer 3 shown in FIG. 5 has a laminated structure in which the main absorbent sheet 31 and the central absorbent sheet 32 are folded.
The main absorbent sheet 31 has a folding structure in which both end portions in the width direction are overlapped on the back surface layer 2 side and folded in three. The main absorbent sheet 31 has a length ranging from the middle part C to the front part F and the rear part R, and has an outer shape of the absorbent layer 3.
The central absorbent sheet 32 has a folded structure in which both ends in the width direction are overlapped on the surface layer 2 side and folded in three. The central absorbent sheet 32 is narrower than the folded main absorbent sheet 31 in the folded state, and the length in the longitudinal direction is shorter than the main absorbent sheet 31, and the width direction center of the middle portion C Are arranged. The central absorbent sheet 32 is housed inside the folded structure of the main absorbent sheet 31.

In the above-described laminated structure, the portion 31A on the skin side of the central absorbent sheet 32 of the main absorbent sheet 31 is the skin side 3A of the absorbent layer 3 described above. In addition, a portion 31B on the non-skin side of the central absorbent sheet 32 of the main absorbent sheet 31 is the non-skin side 3B of the absorbent layer 3 described above.
Further, in the middle portion C, a portion where the main absorbent sheet 31 and the central absorbent sheet 32 are laminated becomes the high basis weight portion 33 described above. It is preferable that the adhesion part 7 be distribute | arranged to the non-skin side of the back surface layer 2 which overlaps with this high basis weight part 33 in planar view.

In the absorption layer 3, the ratio (H2 / H1) of the thickness (H2) of the portion other than the high basis weight portion 33 to the thickness (H1) of the high basis weight portion 33 is from the viewpoint of being able to be used without discomfort to the skin surface 1/5 or more is preferable and 1/3 or more is more preferable. The ratio (H2 / H1) is preferably 4/5 or less, more preferably 2/3 or less, from the viewpoint of fit.
The ratio (M2 / M1) of the basis weight (M2) of the part other than the high basis weight part 33 to the basis weight (M1) of the high basis weight part 33 in the absorbent layer 3 is the liquid diffusion prevention In light of the above, 1⁄4 or more is preferable, and 1⁄3 or more is more preferable. The ratio (M2 / M1) is preferably 7/8 or less, more preferably 2/3 or less, from the viewpoint of preventing deflection due to the difference in rigidity between the high basis weight part and the low basis weight part.

The folded structure of the central absorbent sheet 32 is not limited to the embodiment shown in FIG. For example, it may be folded as shown in FIGS. 6 (A) to 6 (D). FIG. 6A shows an aspect in which both ends in the width direction of the central absorbent sheet 32 are folded back in the S-shape on the skin side and the non-skin side, respectively. FIG. 6B shows an aspect in which the sheet is folded in half in the width direction. 6 (C) and 6 (D) show a mode in which the portions folded in three in the width direction are equal in length.

The folding structure of the main absorbent sheet 31 is not limited to the mode shown in FIG. For example, it may be similar to those shown in FIGS. 6 (A) to 6 (D) shown as the folded structure of the central absorbent sheet 32. Moreover, the structure which laminated | stacked the sheet | seat of 2 sheets divided into the skin surface side and the non-skin surface side may be sufficient. Furthermore, it is not limited to the aspect which includes central absorptive sheet 32 inside the folding structure of main absorptive sheet 31, but does not include the central absorbent sheet on the non-skin side of the folding structure of main absorptive sheet 31 32 may be laminated.
However, when the central absorbent sheet 32 is included in the folded structure of the main absorbent sheet 31, the volatile component of the cooling agent is more easily retained, which is preferable from the viewpoint of the action of the communication portion 8 described later.

It is preferable that the overlapping portions of the absorbent sheets are not joined regardless of the laminated structure of the absorbent layer 3. Thereby, the space between the layers of the absorption layer 3 is easily formed, and the opening and closing property between the above layers is enhanced. As a result, feeding of the volatile component of the cooling agent to the skin through the communication portion 8 can be more easily expressed.

In the present embodiment, as shown in FIGS. 7-9, the absorbent layer 3 preferably has a communicating portion 8 from the skin side surface in the thickness direction.

The communicating portion 8 is a ventilation means disposed in the thickness direction of the absorbent layer 3. It is preferable that the communication part 8 is arrange | positioned at least on the skin surface side of the absorption layer 3 as an aeration means to guide | induce the volatile component of a cooling agent to a skin surface. The communicating portion 8 functions as a moving path of the volatile component of the cooling agent, and a moving path of air due to the deformation of the absorbing layer 3 and the like. These actions are effective from the viewpoint of maintaining the cooling sensation effect longer than the distribution of the cooling agent content described above. In particular, when the residual amount of the cooling agent decreases as time passes, the volatile components of the cooling agent accumulated in the interior of the absorbent layer 3 (for example, between the layered sheets) are sufficiently absorbed onto the skin. Can be sent. For example, when the cooling agent remains behind the absorption layer 3, even after the cooling sensation emitted from the surface layer 1 and the intermediate fiber layer 4 becomes thin, the presence of the communicating portion 8 with a time difference causes the inside of the absorption layer 3 to It is possible to positively feed the volatile component of the cooling agent to the skin surface. The cooling agent is more effectively delivered, for example, by the deformation of the absorbent layer accompanying the movement of the wearer's body when wearing a napkin.

In addition, in FIG. 8, although the absorption layer 3 is shown as what has a laminated structure of an absorptive sheet and has the high basis weight part 33, it is not limited to this and can be made into a thing of various aspects. it can. Moreover, in FIG. 8, the aspect which the high basis weight part 33 and the adhesion part 7 overlap is shown, but the aspect which both members do not overlap may be sufficient.
However, from the viewpoint of more effectively sending the volatile component of the cooling agent to the skin by the communication part 8, it is more preferable that the absorbent layer 3 have the above-described laminated structure of the absorbent sheet. If communication part 8 is arranged to absorption layer 3 which has a lamination structure, it will be sent to a skin surface through communication part 8 while temporarily storing the volatile component of the cooling agent between layers, and it will make a feeling of moderate cold feeling longer longer. be able to. At that time, the layers of the absorbent layer 3 are opened and closed according to the movement of the wearer, and the volatile component of the cooling agent through the communication portion 8 can be more easily delivered to the skin side.

The communicating portion 8 may be a gap portion or a penetrating portion without a member of the absorbent layer 3, or may be a compressed portion in which a portion of the member is pressed and depressed, and the basis weight of the member is partially It may be a reduced recess space. As a penetration part, the slit part cut into a long and thin part or the part in which a part of member was notched etc. are mentioned, for example. In the penetration portion and the recess space, an opening is provided to release the volatile component of the cooling agent from the inside to the outside. In the pressing part, the surface area in contact with the outside is increased, which makes it easy to release the volatile component of the cooling agent from the vicinity of the pressing part.

In FIGS. 7-9, the through portion 8 (slit portion 81) disposed in the absorbent layer 3, the surface layer 1, the intermediate fiber layer 4 and the absorbent layer 3 are squeezed (embossed) in the thickness direction as the communicating portion 8. A leak-proof groove 83 is provided. In addition, the aspect of the slit part 81 as penetration part 8 shown below can be suitably applied also to penetration parts other than a slit part.

The slit portion 81 has a length extending along the longitudinal direction of the absorbing layer 3, and a plurality of the slit portions 81 are distributed in the surface direction of the absorbing layer 3. In the present embodiment, the plurality of slits 81 are spaced apart in the longitudinal direction, and the rows in the longitudinal direction are spaced apart in the width direction. Thereby, the volatile component of the cooling agent can be delivered to the skin from a wide region of the absorbing layer 3 while suitably controlling the exudation direction of the cooling agent in the planar direction. However, the distribution arrangement of the slit portion 81 is not limited to this, and various embodiments can be made such that the volatile component of the cooling agent in the absorption layer 3 can be effectively delivered to the skin.

The “slit portion” referred to here can be defined as a cut portion having a member cutting width of 0.5 mm or less, preferably 0.3 mm or less, more preferably 0.2 mm or less. The “width” of the slit portion 81 refers to the distance (opening width) between the disconnected members in the direction orthogonal to the length direction in which the slit portion 81 extends in a plan view of the napkin 10. The width of the slit portion 81 can be measured with a digital microscope VHX-900 manufactured by Keyence Corporation in a natural state in which the absorbent layer 3 is taken out from the napkin 10 and left on a horizontal table and no tension is applied. At the time of measurement, measurement magnification is appropriately adjusted and measured.

The slit portion 81 may have various depths in the thickness direction of the absorbing layer 3. For example, it may be a predetermined depth from the skin surface side, or may extend over the entire thickness direction of the absorbent layer 3. From the viewpoint of expressing the function as a communicating part that delivers the volatilized component of the cooling agent inside the absorbing layer 3 to the skin, the slit part 81 contains the cooling agent at least from the skin surface side of the absorbing layer 3 Preferably, it is disposed to a predetermined depth to the region. In particular, the presence of the penetrating portion (slit portion 81) in the high basis weight portion 33 of the absorbent layer 3 is preferable because the volatile component of the cooling agent is easily sent out to the skin.

Moreover, the slit part 81 may penetrate not only the case where it is distribute | arranged to the absorption layer 8 but the intermediate fiber layer 4 to the absorption layer 3 in the same position. Thereby, the passage of the volatile component of the cooling agent can be continued from the absorbing layer 3 to the intermediate fiber layer 4 and can be smoothly delivered from the inside of the absorbing layer 3 to the skin.

On the other hand, the leakage preventing groove 83 disposed as the communicating portion 8 is formed by squeezing from the surface layer 1 to the intermediate fiber layer 4 and the absorbing layer 3. That is, the surface layer 1, the intermediate fiber layer 4 and the absorbent layer 3 are recessed at the same position, and the distance between the layers is reduced. Thereby, in the vicinity of the leak-proof groove 83, a passage to the skin side of the volatile component of the cooling agent is made, and the component volatilized by the cooling agent contained in the absorbent layer 3 and the intermediate fiber layer 4 is delivered to the skin. It will be easier. Moreover, the range and the quantity which a cooling agent exudes to the width direction can be restrict | limited by the leak-proof groove 83, and the excessive stimulation by the cool feeling to a wearer's buttocks vicinity can be suppressed.

From the viewpoint of preventing the lateral leakage of the excrement fluid and preventing the exudation of the cooling agent in the width direction, the leakage preventing groove 83 is a shape that extends in parallel in the longitudinal direction across at least the liquid receiving area C1 in plan view. It is preferable to have In the present embodiment, the leakage preventing groove 83 extends in the longitudinal direction (Y direction) from both sides of the liquid receiving area C1 at the middle portion C, and is connected and annularly formed at the front portion F and the rear portion R Have. Furthermore, the leakage preventing groove 83 has an arc-shaped portion in the front portion F and the rear portion R in the annular portion. The annular and arc-shaped leakproof grooves 83 are both symmetrical about the widthwise center line L extending in the longitudinal direction of the napkin 10 as an axis.
The planar shape of the leakage preventing groove 83 may be formed by a continuous line, or may be a linear arrangement of intermittent squeezed portions. Intermittently means, for example, a dotted line, a dotted line (perforated), and the like. The leakage preventing groove 83 may be disposed singly or in a double or more.

It is preferable that the aforementioned slit portion 81 and the leakage preventing groove 83 be in partial contact with each other. Here, “contact” means that a part of the slit portion 81 overlaps with the depressed portion of the absorbent layer 3 squeezed in the leakage preventing groove 83. By this, even when external pressure occurs when the napkin 10 is worn, the opening of the slit portion 81 does not open too much, and excessive volatilization of the cooling agent from the opening of the slit 8 can be suppressed. It can be realized effectively.

As described above, the communicating portion 8 is disposed at least in the absorbent layer 3 and may be disposed only in the absorbent layer 3 or may penetrate the absorbent layer 3 and the intermediate fiber layer 4 at the same position. It may penetrate the layer 1, the intermediate fiber layer 4 and the absorbent layer 3 at the same position. If the communicating part 8 is a penetrating part that penetrates the absorbing layer 3, the passage of the volatile component of the cooling agent is continuous along the thickness direction of the absorbing layer 3 and is smoothly delivered from inside the absorbing layer 3 to the skin Can.
Moreover, apart from this, at least one of the surface layer 1 and the intermediate fiber layer 4 may be disposed as the communicating portion 8 in a concave shape in the thickness direction (for example, only the surface layer 1 or the surface layer 1 And point embossing to squeeze the intermediate fiber layer 4 etc.).

Moreover, as a specific example in the case where the communication part 8 is the recessed part space 82 with a partially small basis weight,

absorption layer

310A, 310B shown to FIG. 10 (A) and (B) is mentioned, for example. These are a piled body of hydrophilic fibers or a mixed piled body of hydrophilic fibers and a highly water-absorbing polymer material, having a predetermined thickness and having a concavo-convex shape with a partially reduced basis weight. .
Specifically, the absorbent layer 310A shown in FIG. 10A has a plurality of block-shaped convex portions 311 on the surface layer 1 side (skin surface side), and the basis weight is small between the

convex portions

311 and 311. A plurality of recess spaces 82 are provided as the communication portion 8. Further, the absorbent layer 310B shown in FIG. 10B has a plurality of block-shaped convex portions 311 and concave portion spaces 82 as the communicating portions 8 on the back surface layer 2 side (non-skin surface side). A thin skin portion 312 is provided on the back surface layer 2 side in FIG. 10A and on the surface layer 1 side in FIG. 10B to close the bottom of the recess space 82 and connect the convex portions 311 to each other.

In the present embodiment, from the viewpoint of suppressing the stimulation to the sensitive part of the skin, the side sheet 5 mentioned above straddles both widthwise end edges 39 of the absorption layer 3 from the width direction outer side of the absorption layer 3, It is preferable to extend it. In addition, at least in the middle portion C, the inner end of the side sheet 5 is preferably outside in the width direction than the communication portion 8 which is located most outward in the width direction. As a result, even when the cooling agent exudes beyond the communicating portion 8, the side sheet 5 can prevent the volatile component of the cooling agent from directly stimulating the area around the buttocks of the wearer. . At this time, it is preferable from the viewpoint of more effective suppression of skin irritation that the side sheet 5 has lower air permeability than the surface layer 1. The air permeability can be appropriately set by the method used for this type of article. For example, when the side sheet 5 is made of non-woven fabric, air permeability can be suppressed by narrowing the inter-fiber distance or selecting an oil agent to be used. It is preferable that the air permeability of the side sheet 5 is lower than the air permeability of the surface layer 1 when the air permeability is measured in accordance with JIS L1913 "6.8.2 Gurley type". When the side sheet is too small to measure in the Gurley format, the side sheet is attached to a non-air-permeable film material (preferably Kokuyo OHP film etc.) having an opening smaller than that size, and the measurement is performed. Conduct and convert the opening area value into the area (642 mm ² ) specified in the Gurley format.

What is used for the article of this kind can be used without particular limitation as a forming material of the member constituting the napkin 10.

As a cooling agent, it stimulates the temperature receptor on the wearer's skin and / or mucous membrane surface and conveys a feeling of coolness and refreshing to the wearer without changing the temperature on the skin and / or mucous membrane surface Various agents that can be used can be used. Examples thereof include cyclohexyl derivatives, cyclohexanol derivatives, carboxamides and the like, as described in paragraphs [0006] to [0086] of JP-A-2015-12918. The cooling agent can be used alone or in combination of two or more.
Among them, water-insoluble or poorly water-soluble ones are preferable from the viewpoint of refreshing feeling and quick action and persistence due to odor. Menthyl lactate and menthol are preferable as water insoluble or poorly water soluble ones. The term "water-insoluble or poorly water-soluble" as used herein means that the solubility is 1 g or less in 1 L of water at 25 ° C, and particularly "water-insoluble" is 0.1 g or less in 1 L of water at 25 ° C Say that it is soluble in water.
A cooling agent can be contained in the napkin 10 by various methods. For example, they may be contained in the napkin 10 in a state of being dissolved in a solvent, or may be contained without using a solvent. In addition, the cooling agent may be contained in the napkin 10 together with a delivery means such as encapsulation in microcapsules. As the solvent, various ones commonly used can be adopted. For example, dipropylene glycol and the like can be mentioned.

As a cooling agent, in particular, it is preferable to include menthol and menthyl lactate because the cooling effect can be felt quickly and gently after wearing, and the durability can be enhanced. From the same viewpoint, the content ratio of menthol and menthyl lactate is preferably 0.01 or more, more preferably 0.02 or more, and preferably 0.2 or less, in the mass ratio of the former / the latter. Is more preferred.

As the absorbent layer 3, various forms usually used as an absorbent article can be adopted without particular limitation as long as the above-mentioned distribution of the amount of the cooling agent can be realized. For example, a stack of hydrophilic fibers or a mixed stack of hydrophilic fibers and a superabsorbent polymer material may be covered with a hydrophilic covering sheet. In addition, it may be composed of a thin absorbent sheet in which a superabsorbent polymer material is sandwiched and fixed between two sheet-like fiber layers made of hydrophilic fibers.

As a hydrophilic fiber which comprises the absorption layer 3, what carried out the hydrophilization treatment of the hydrophobic fiber, and the thing which itself is hydrophilic are mentioned. In particular, those which themselves are hydrophilic and have water retention are preferred. As the latter hydrophilic fibers, natural fibers, regenerated cellulose fibers or semi-synthetic fibers are mentioned as preferable examples. As the hydrophilic fiber, in particular, pulp and rayon are preferable, and pulp is more preferable. Further, crosslinked cellulose fibers obtained by crosslinking the intramolecular and / or intermolecular of cellulose fibers or bulky cellulose fibers obtained by mercerizing wood pulp may be used. Examples of the pulp include wood pulp such as softwood kraft pulp and hardwood kraft pulp, and natural cellulose fibers such as cotton pulp and straw pulp, but not limited thereto. These pulps can be used alone or in combination of two or more.

The superabsorbent polymer material constituting the absorbent layer 3 can be obtained, for example, by polymerizing a water-soluble ethylenic unsaturated monomer composed mainly of acrylic acid or acrylate and optionally added with a crosslinking agent. Hydrogel materials are included. Also, polyethylene oxide, polyvinyl pyrrolidone, crosslinked products of sulfonated polystyrene and polyvinyl pyridine, saponified starch-poly (meth) acrylonitrile graft copolymer, starch-poly (meth) acrylic acid graft copolymer, starch-poly ( The hydrolyzate of a (meth) acrylic ester graft copolymer etc. are mentioned. These superabsorbent polymer materials can be used alone or in combination of two or more. As the highly water-absorbing polymer material, a material capable of absorbing and holding 20 times or more, particularly 50 times or more of its own weight of pure water and capable of gelation is preferable.
As the shape of the superabsorbent polymer material, various materials used for the absorbent layer can be used without particular limitation. For example, spherical shape, granular shape, fibrous shape, bowl shape, lump shape etc. are mentioned.

The surface layer 1 can use various sheets having liquid permeability. In consideration of the goodness of the touch, a hydrophilic non-woven fabric is preferable, a thermal bond non-woven fabric is more preferable, and an air-through non-woven fabric is particularly preferable. The fiber constituting the nonwoven fabric of the surface layer 1 is preferably a thermoplastic resin fiber subjected to hydrophilization treatment, and the fiber is preferably a fiber subjected to a three-dimensional crimp such as a secondary crimp or a tertiary crimp. . Specifically, the fibers constituting the non-woven fabric of the surface layer 1 are polyethylene, polypropylene, polyester (polyethylene terephthalate etc.), nylon, and composite fibers thereof before being cut to a predetermined length to form staples At the stage of, it hydrophilizes by coating various hydrophilizing agents. As the hydrophilizing agent, various alkyl sulfonates represented by α-olefin sulfonate, acrylate, acrylate / acrylamide copolymer, ester amide, ester amide salt, polyethylene glycol and derivatives thereof, water-soluble Hydrophilization treatment with a commonly used hydrophilizing agent can be used, such as polyester resin, various silicone derivatives, various saccharide derivatives, and mixtures thereof.

As the back surface layer 2, various materials having leak resistance can be used. For example, a non-moisture permeable or moisture-permeable film alone, or a combination of a film and a non-woven fabric, or a water-repellent non-woven fabric (SMS, SMMS, etc.) can be used. It is most preferable to use a non-moisture-permeable film alone as the leak-proof material from the viewpoint of cost and matching with the anti-slip adhesive.

The intermediate fiber layer 4 is preferably one having hydrophilicity and excellent in liquid diffusibility. Non-woven fabrics containing thermoplastic fibers can be mentioned. As the non-woven fabric, non-woven fabrics obtained by various manufacturing methods can be used. For example, an air through non-woven fabric in which heat fusion points of fibers are formed by air through method on fiber web obtained by card method or air laid method, heat fusion point of fibers is formed by heat roll method on fiber web obtained by card method Various non-woven fabrics such as heat-roll non-woven fabric, heat-embossed non-woven fabric, spunlace non-woven fabric, needle punched non-woven fabric, resin-bonded non-woven fabric, etc. can be used.

The side sheet 5 is preferably a water repellent non-woven fabric, and non-woven fabric manufactured by the card method, spun bonded non-woven fabric, meltblown non-woven fabric, spun lace non-woven fabric, heat roll non-woven fabric, needle punched non-woven fabric etc. Various non-woven fabrics treated with water can be used. Particularly preferably, for example, a spunbond nonwoven fabric, a spunbond-meltblown (SM) nonwoven fabric, a spunbond-meltblown-spunbond (SMS) nonwoven fabric and the like are used.

The absorbent article of the present invention is not limited to the sanitary napkin of the above embodiment, and can be applied to, for example, panty liners, incontinence pads, urine collecting pads, disposable diapers and the like. Moreover, it is effective not only to menstrual blood but also to other things such as urine, orimono, soft stools and the like. In addition to the components described above, members may be incorporated appropriately in accordance with the application and function.

When the absorbent article of the present invention is a product such as a sanitary napkin or a panty liner which is carried in a bag for each product, it is preferable to be individually packaged. Specifically, it is preferable that the absorbent article is individually wrapped so as to be longitudinally folded so that the surface layer is inside, and wrapped by the packaging material for individual packaging. By using the individual package, it is possible to make the article highly portable while protecting the hygiene of the surface layer (use side) that touches the skin, and it is possible to enhance the convenience of the user.

Regarding the above-mentioned embodiment, the present invention further discloses the following absorbent article.

<1> An absorbent article comprising a surface layer, a back surface layer, and an absorption layer disposed between the surface layer and the back surface layer, and an intermediate fiber layer between the surface layer and the absorption layer. The absorbent layer, the surface layer and the intermediate fiber layer each contain a cooling agent, and the content per unit area of the cooling agent is larger in the intermediate fiber layer than in the absorption layer, and An absorbent article having more in the intermediate fiber layer than in the surface layer.
<2> The absorbent article according to <1>, which is the intermediate fiber layer, the absorbent layer, and the surface layer in descending order of the content per unit area of the cooling agent.
<3> The absorbent article according to <1> or <2>, wherein the liquid diffusivity of the surface layer is smaller than the liquid diffusivity of the intermediate fiber layer and the absorbent layer.
<4> The absorbent article has a longitudinal direction and a width direction orthogonal to the longitudinal direction, and along the longitudinal direction, an intermediate portion including a liquid receiving region facing the excretory portion of the wearer, and both end sides thereof The absorbent layer is provided with a high basis weight portion whose basis weight is larger than that of the surrounding portion in the middle portion, the absorbent layer according to any one of <1> to <3> Absorbent article.
<5> The ratio H2 / H1 of the thickness H2 of the portion other than the high basis weight portion to the thickness H1 of the high basis weight portion in the absorption layer is 1/5 or more and 4/5 or less. The absorbent article as described in 4>.
<6> The ratio M2 / M1 of the basis weight M2 of the part other than the high basis weight part to the basis weight M1 of the high basis weight part in the above-mentioned absorbent layer is 1/4 or more and 7/8 or less. The absorbent article as described in <4> or <5>.
<7> The absorbent article according to any one of <1> to <6>, wherein the absorbent layer has a laminated structure of an absorbent sheet.
<8> The absorbent article according to any one of <4> to <6>, wherein the absorbent layer has a laminated structure of absorbent sheets, and the high basis weight portion has a larger number of layers than that before and after that. .
<9> The non-skin side surface of the back surface layer according to any one of <4> to <8>, wherein an adhesive part for fixing clothes is disposed in a part overlapping in plan view with the high basis weight part. Absorbent article.
<10> The absorbent article according to any one of <1> to <9>, wherein an average inter-fiber distance in the surface layer is larger than an average inter-fiber distance in the intermediate fiber layer.
<11> The absorbent according to any one of <1> to <10>, wherein the content per unit area of the cooling agent is larger on the skin side than on the non-skin side of the absorbent layer. Article <12> The absorbent article according to any one of <1> to <11>, wherein the absorbent layer has a communicating portion in the thickness direction from the skin side surface.
<13> The absorbent article according to <12>, wherein the communication part is a penetration part penetrating the absorption layer.
<14> The absorbent article has a longitudinal direction and a width direction orthogonal to the longitudinal direction, and along the longitudinal direction, an intermediate portion including a liquid receiving region facing the excretory portion of the wearer, and both end sides thereof The absorbent layer is provided with a high basis weight portion whose basis weight is larger than that of the surrounding portion, and the high basis weight portion is provided with the penetration portion. The absorbent article as described in 13>.
<15> The absorbent article according to any one of <1> to <14>, wherein the cooling agent is water insoluble or poorly water soluble.
<16> The absorbent article according to <15>, which contains menthyl lactate as the cooling agent.
<17> The absorbent article according to <16>, which comprises menthol as the cooling agent.
<18> The absorbent article according to <17>, wherein the mass ratio of menthol to menthyl lactate is 0.01 or more and 0.2 or less as the former / the latter.
<19> The absorbent article according to any one of <1> to <18>, wherein a side sheet having air permeability smaller than that of the surface layer is laminated on both sides of the surface contact side of the surface layer.
<20> The absorbent article according to any one of <1> to <19>, including a wing portion extended outward in the width direction of the absorbent layer.
<21> The absorbent article according to any one of <1> to <20>, which is a sanitary napkin.

EXAMPLES The present invention will be described in more detail based on examples given below, but the invention is not meant to be limited by these.

(Production example)
A sanitary napkin having a structure shown in FIG. 5 was prepared.
Specifically, an absorbent layer (length: 190 mm, width: 75 mm) having a laminated structure in which the main absorbent sheet and the central absorbent sheet are folded as shown in FIG. the cooling agent solution in propylene glycol, across the skin surface the entire length of the body the absorbent sheet of the absorbent layer, menthol 2.5mg (0.18g ^{/ m} 2), menthyl lactate 25mg (1.8g / ^{m 2} It coated so that it might become. After leaving the obtained absorbent layer in an airtight container for 3 weeks at room temperature, place the intermediate fiber layer and the surface layer on the skin side of the absorbent layer, and on the non-skin side of the absorbent layer A back layer was disposed, and an adhesive portion was further formed on the non-skin side of the back layer to prepare a sanitary napkin. The resulting sanitary napkin is placed on an exterior material having a larger area than the sanitary napkin so as to face the back surface layer, and then folded in a three-fold shape to seal the opposite surface of the exterior material. The sample was allowed to stand for a week to obtain a sanitary napkin sample of the production example.
The surface layer is composed of upper and lower layers, the upper layer side is a fiber diameter of 4.4 dtex, and the lower side is a core-sheath composite fiber (core is polyethylene terephthalate, sheath is polyethylene), with a fiber diameter of 3.3 dtex. Made of a non-woven sheet having a weight of 0.9 g and a basis weight of 25 g / m ² . The intermediate fiber layer was made of a non-woven sheet having a thickness of 0.5 mm and a basis weight of 25 g / m ² , which is made of a synthetic resin made of a composite resin of polyethylene / polyethylene terephthalate having a fiber diameter of 2.2 dtex. About an absorption layer, it was created according to Example 2 of the patent 2963647 as a main body absorptive sheet and a center absorptive sheet. However, High Bulk Additive HBA manufactured by Weyerhauser Paper was used as the cross-linked treated pulp, and Aquaric CA manufactured by Nippon Shokubai Co., Ltd. was used as the superabsorbent polymer. Was used. The main absorbent sheet had a size of 190 mm × 75 mm, and the central absorbent sheet had a size of 90 mm × 35 mm.

(Comparative manufacturing example)
A sanitary napkin equivalent to a commercial product containing a cooling agent was used as a comparative production example.
Specifically, the same amount of the cooling agent as in the production example was applied to the intermediate fiber layer having the following configuration over the entire length of the intermediate fiber layer on the skin surface side. Immediately thereafter, the surface layer of the following constitution is disposed on the skin surface side of the intermediate fiber layer, and the absorbent layer and the back layer of the following constitution are disposed on the non-skin surface side of the intermediate fiber layer. The pressure-sensitive adhesive portion was formed to make a sanitary napkin. The obtained sanitary napkin was housed in the outer packaging material as in the production example, and allowed to stand at room temperature for 3 weeks to obtain a sanitary napkin of the comparative production example.
The surface layer was made of a non-woven sheet having a thickness of 1.1 mm and a basis weight of 25 g / m ² , which was composed of core-sheath composite fibers (core is polyethylene terephthalate, sheath is polyethylene) with a fiber diameter of 3.0 dtex. . The intermediate fiber layer was a non-woven sheet having a thickness of 1.6 mm and a basis weight of 30 g / m ² , made of a synthetic resin made of a composite resin of polyethylene / polyethylene terephthalate having a fiber diameter of 3.0 dtex. The absorbent layer is a mixture of a water-absorbent polymer: pulp fiber: core-sheath type composite fiber (core is polyethylene terephthalate, sheath is polyethylene) at a mass ratio of 10:25:65 and a thickness of 2 mm and a basis weight of 200 g / m ² It shall consist of a piled body.

The content of the cooling agent was measured based on the method described in (Method of measuring the amount of cooling agent per unit area).
In the sanitary napkin of the production example, the proportion of the cooling agent content per unit area is 10% in the surface layer, 25% in the intermediate fiber layer, 12% in the main absorbent sheet, and 5% in the central absorbent sheet , Was 49% in the back layer. On the other hand, in the sanitary napkin of the comparative production example, the proportion of the cooling agent content per unit area is 19% in the surface layer, 19% in the intermediate fiber layer, 10% in the absorbing layer, and 52% in the back layer. there were.

About the sanitary napkin of the said manufacture example and a comparative manufacture example, the wearing test was done to 10 women. As a result, compared with the sanitary napkin of the comparative production example, in the sanitary napkin of the production example, there were many evaluations that the intensity of the cool sensation was just enough, and the cold sensation was maintained for a sufficient time. .

While the present invention has been described in conjunction with the embodiments and examples thereof, it is not intended that the invention be limited in any detail of the description unless otherwise specified, and the spirit of the invention as set forth in the appended claims. We believe that it should be interpreted broadly without violating the scope.

Reference Signs List 1 front surface layer 2 back surface layer 3 absorbent layer 4 intermediate fiber layer 5 side sheet 6 wing portion 8 communicating portion 10 sanitary napkin

Claims

An absorbent article comprising a front surface layer, a back surface layer, and an absorption layer disposed between the front surface layer and the back surface layer, and an intermediate fiber layer between the front surface layer and the absorption layer,
The absorbing layer, the surface layer and the intermediate fiber layer each contain a cooling agent,
An absorbent article, wherein the content per unit area of the cooling agent is larger in the intermediate fiber layer than in the absorbent layer, and in the intermediate fiber layer more than the surface layer.
The absorbent article according to claim 1 which is said intermediate fiber layer, said absorption layer, and said surface layer in descending order of content per unit area of said cooling agent.
The absorbent article according to claim 1 or 2, wherein the liquid diffusivity of the surface layer is smaller than the liquid diffusivity of the intermediate fiber layer and the absorbent layer.
The absorbent article has a longitudinal direction and a width direction orthogonal to the longitudinal direction, and is positioned at an intermediate portion including a liquid receiving region facing the wearer's excrement along the longitudinal direction, and at both ends thereof The absorbent article according to any one of claims 1 to 3, which has a front portion and a rear portion, and the absorbent layer is provided with a high basis weight portion in which the basis weight is larger than the surrounding portion in the middle portion.
In the absorption layer, the ratio (H2 / H1) of the thickness (H2) of the portion other than the high basis weight to the thickness (H1) of the high basis weight is 1/5 or more and 4/5 or less The absorbent article according to claim 4.
In the absorption layer, the ratio (M2 / M1) of the basis weight (M2) of the part other than the high basis weight part to the basis weight (M1) of the high basis weight part is 1/4 or more and 7/8 or less The absorbent article according to claim 4 or 5, which is
The absorbent article according to any one of claims 1 to 6, wherein the absorbent layer has a laminated structure of an absorbent sheet.
The absorbent article according to any one of claims 4 to 6, wherein the absorbent layer has a laminated structure of absorbent sheets, and the number of laminated layers in the high basis weight part is larger than that in the front and back.
The absorbent article according to any one of claims 4 to 8, wherein a non-skin side surface of the back surface layer is provided with an adhesive part for fixing clothes in a part overlapping with the high basis weight part in plan view.
The absorbent article according to any one of claims 1 to 9, wherein an average inter-fiber distance in the surface layer is larger than an average inter-fiber distance in the intermediate fiber layer.
The absorbent article according to any one of claims 1 to 10, wherein the content per unit area of the cooling agent is greater on the skin side than on the non-skin side of the absorbent layer.
The absorbent article according to any one of claims 1 to 11, wherein the absorbent layer has a communicating portion from the skin side surface in the thickness direction.
The absorbent article according to claim 12, wherein the communication part is a penetration part penetrating the absorbent layer.
The absorbent article has a longitudinal direction and a width direction orthogonal to the longitudinal direction, and is positioned at an intermediate portion including a liquid receiving region facing the wearer's excrement along the longitudinal direction, and at both ends thereof 14. The apparatus according to claim 13, further comprising a front portion and a rear portion, wherein the absorbent layer includes a high basis weight portion having a basis weight larger than that of the surrounding portion in the middle portion and the penetration portion in the high basis weight portion. Absorbent articles.
The absorbent article according to any one of claims 1 to 14, wherein the cooling agent is water insoluble or poorly water soluble.
The absorbent article according to claim 15, comprising menthyl lactate as the cooling agent.
The absorbent article according to claim 16, comprising menthol as the cooling agent.
The absorbent article according to claim 17, wherein a mass ratio of said menthol to said menthyl lactate is 0.01 or more and 0.2 or less as the former / the latter.
The absorbent article according to any one of claims 1 to 18, wherein a side sheet having lower air permeability than the surface layer is laminated on both sides of the skin contact surface side of the surface layer.
The absorbent article according to any one of claims 1 to 19, further comprising a wing portion extending outward in the width direction of the absorbent layer.
The absorbent article according to any one of claims 1 to 20, which is a sanitary napkin.