JP2006061681A - Pants type disposable diaper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pants type disposable diaper in which the moving and falling down of the diaper hardly occurs due to the movement of a wearer during wearing the diaper. <P>SOLUTION: The whole length of the diaper in the expanded state in the longitudinal direction is 440 to 530 mm, the length of the side seal portions is 90 to 140 mm. The average value of a pressure of a second area at the time of wearing the diaper is 0.9 to 1.8 kPa and the maximum value of the same is not more than 2.5 kPa, when virtual dividing lines dividing the area from the waist opening portion to the leg opening portions in the diaper in the bonding state into four in the longitudinal direction are made, and a first area, a second area, a third area, and a fourth area are virtually thought in series from the waist opening portion side. The pressures of the first area and the third area at the time of wearing the diaper are lower than that of the second area. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a pants-type disposable diaper, and more particularly to a pants-type disposable diaper for infants.

  In a pants-type disposable diaper, an elastic member extending in the width direction of the diaper is disposed between a waist opening and a leg opening. For example, at least the ventral side of the diaper is defined between a first waist region defined by a maximum of 20 mm in each of the upper and lower sides with the front end edge of the core as a boundary, and between the first waist region and the leg opening. A pants-type disposable diaper having a second waistline area, wherein the arrangement interval dimension of the elastic members in the first waistline area is smaller than the arrangement interval dimension of the elastic members in the second waistline area. It has been proposed (see Patent Document 1). In this diaper, the first torso area is more than the second torso area in terms of adhesion to the skin while substantially equalizing the surface pressure per fixed area in the first torso area and the second torso area. By making it good, it is intended to prevent leakage without impairing the feeling of wearing the diaper.

  Also known is a pants-type disposable diaper that has a strong contraction force acting on the upper part of the wearer's torso and lumbar bone by gradually reducing the spacing between the elastic members toward the leg opening. (See Patent Document 2).

  However, in these diapers, strong tightening pressure is applied to the waist opening, which may make it difficult to wear the diaper. In addition, the diaper is slipped off during wearing, the appearance is deteriorated, and the wearer may not easily move due to the slipping off, and urine and feces may leak.

Japanese Patent Laid-Open No. 9-84826 Japanese Utility Model Publication No. 6-421

  Accordingly, it is an object of the present invention to provide a pants-type disposable diaper that can eliminate the various drawbacks of the above-described prior art.

The present invention is a pants-type disposable diaper having a waist opening and a pair of leg openings,
The total length of the unfolded state diaper in the longitudinal direction is 440 to 530 mm, and the unfolded state diaper side seal portion has a length of 90 to 140 mm.
An area from the waist opening to the leg opening in the bonded diaper is drawn with a virtual dividing line that is equally divided into four in the longitudinal direction, and the first area, the second area, and the third area in that order from the waist opening side. When the fourth region is virtually considered, the average value of the pressure when wearing the diaper of the second region is 0.9 to 1.8 kPa and the maximum value is 2.5 kPa or less, and the first An area | region and a 3rd area | region achieve the said objective by providing the underpants type disposable diaper by which the pressure at the time of diaper wear is made lower than a 2nd area | region.

  The pants-type disposable diaper according to the present invention has a good wearing state (appearance) immediately after being worn, and it is difficult for the diaper to fall off due to the movement of the wearer while wearing the diaper. In particular, bumping of the crotch of the diaper is difficult to occur. Therefore, the appearance of the diaper in a worn state can be kept good. The wearer's movement is not hindered due to the falling of the diaper, and the leakage of urine and feces is difficult to occur. Moreover, it is prevented that the elastic member distribute | arranged to the diaper overtightens a wearer's body, and a feeling of wear becomes favorable.

  The present invention will be described below based on preferred embodiments with reference to the drawings. The perspective view of one Embodiment of the underpants type disposable diaper of this invention is shown by FIG. FIG. 2 is an exploded perspective view showing a state before the diaper shown in FIG. 1 is assembled. FIG. 3 shows a plan view of the developed state of the diaper in FIG. In the following description, the developed state of the diaper means a state before the side seal portion of the diaper is joined, and the joined state means a state after the side seal portion is joined.

  The diaper 1 of the present embodiment is substantially vertically long having a liquid-permeable top sheet 2, a liquid-impermeable back sheet 3, and a liquid-retaining absorbent core 4 interposed between the two sheets 2 and 3. The absorbent body 10 and the outer packaging material 11 arranged on the back sheet 3 side of the absorbent body 10 are provided.

  The outer packaging material 11 has an hourglass shape in which both side edges are bound inward in the central portion in the longitudinal direction, and defines the outline of the diaper. The outer packaging material 11 is divided in the longitudinal direction into an abdominal side A disposed on the wearer's abdominal side, a back side B disposed on the back side, and a crotch C positioned therebetween. The abdomen A and the back B correspond to the longitudinal front and rear ends of the outer packaging material 11, and the crotch C corresponds to the longitudinal center of the outer packaging material 11. In the outer packaging material 11, both side edges A1 and A2 of the ventral side A and both side edges B1 and B2 of the back side B are joined together, and the diaper 1 has a waist opening 5 and a pair of leg openings 6. It is formed. By this joining, a pair of side seal portions S are formed on the left and right side edges of the diaper 1. For this joining, for example, heat sealing, high frequency sealing, ultrasonic sealing or the like is used.

  The top sheet 2, the back sheet 3, and the absorbent core 4 each have a rectangular shape, and are integrated to form a vertically long absorbent body 10. As the surface sheet 2 and the back surface sheet 3, the same material as that conventionally used for this type of diaper can be used. The absorbent core 4 is made of superabsorbent polymer particles and a fiber material, and is covered with tissue paper (not shown).

  As shown in FIG. 2, side cuffs 8, 8 made of a liquid resistant or liquid impermeable and breathable material are formed on the left and right sides of the absorbent body 10 in the longitudinal direction. Each side cuff 8 has a fixed end and a free end along the longitudinal direction of the absorbent body 10. The fixed end is fixed to the top sheet 2. On the other hand, a side cuff elastic member 81 is arranged in an expanded state in the vicinity of the free end. As a result, the side cuff 8 is erected by contracting the side cuff elastic member 81 during use, and the outflow of liquid in the width direction of the absorbent body 10 is prevented.

  The outer packaging material 11 has at least two nonwoven fabrics, that is, an outer layer nonwoven fabric 12 and an inner layer nonwoven fabric 13 disposed on the inner surface side of the outer layer nonwoven fabric 12. The outer layer nonwoven fabric 12 forms the outer surface of the diaper 1, and the inner layer nonwoven fabric 13 is joined to the inner surface side of the outer layer nonwoven fabric 12 with an adhesive such as a hot melt pressure-sensitive adhesive. From the viewpoint of preventing penetration of liquid from the outside of the diaper and exudation of liquid from the inside, it is preferable that both of the inner layer nonwoven fabric 13 and the outer layer nonwoven fabric 12 are water-repellent nonwoven fabrics.

  The outer packaging material 11 extends outward from the front and rear end edges of the absorbent body 10, and the extended portion is folded back to the absorbent body 10 side. The wrapped outer packaging material 11 covers the front and rear end portions of the absorber body 10 (that is, the top sheet 2 at the front and rear end portions of the absorber body 10).

  A plurality of waist elastic members 51, 51 are arranged along the width direction of the front and rear end portions of the outer packaging material 11 along the front and rear end edges. The waist elastic members 51 and 51 are sandwiched and fixed in an expanded state by the outer layer nonwoven fabric 12 and the inner layer nonwoven fabric 13. The waist elastic members 51, 51 are formed on the elastic members 51, 51 when the side edges A1, A2 of the ventral side A of the diaper 1 and the side edges B1, B2 of the back side B are joined to each other. It arrange | positions so that edge parts may overlap. As a result, as shown in FIG. 1, a substantially continuous ring-shaped waist gather is formed in the vicinity of the waist opening 5 of the diaper 1.

  Leg elastic members 61a and 61b are disposed on the left and right curved portions of the outer packaging material 11, respectively. Each leg part elastic member 61a, 61b is distribute | arranged along the said curved part. Each leg part elastic member 61a, 61b is distribute | arranged between the outer-layer nonwoven fabric 12 and the inner-layer nonwoven fabric 13, and is fixed to both the nonwoven fabrics 12 and 13 by the predetermined joining means in the expansion | extension state. One end of each leg part elastic member 61a, 61b overlaps in the crotch part C. On the other hand, the other end is terminated at the position of each side edge of the ventral side A and the back side B. When each leg part elastic member 61a, 61b joins both the side edges A1, A2 of the belly side part A of the diaper 1 and both side edges B1, B2 of the back side part B, the both elastic members 61a, 61b It arrange | positions so that edge parts may overlap. As a result, as shown in FIG. 1, a substantially continuous ring-shaped leg gather is formed in the vicinity of the leg openings 6, 6 of the diaper 1.

  In the diaper 1 of the present embodiment, as shown in FIG. 3, the region from the waist opening 5 to the leg opening 6 in each of the ventral side A and the back side B of the joined diaper 1 is defined as the diaper 1. A virtual dividing line that is equally divided into four in the longitudinal direction is drawn, and four regions of the first region 7A, the second region 7B, the third region 7C, and the fourth region 7D are virtually considered in order from the waist opening side. Each region 7 </ b> A to 7 </ b> D extends in the width direction of the diaper 1. Of these four regions, the waist elastic member 51 is mainly present in the first region 7A. Further, leg portion elastic members 61a and 61b mainly exist in the fourth region 7D. A large number of elastic members extending in the width direction of the diaper 1 are arranged in the second region 7B and the third region 7C between the first region 7A and the fourth region 7D. Among these elastic members, one existing in the second region 7B is called a first elastic member 71a, and one existing in the third region 7C is called a second elastic member 72a.

  Both the first elastic member 71 a and the second elastic member 72 a extend between the left and right side edges of the diaper 1 (that is, the left and right side edges of the outer packaging material 11) and the left and right side edges of the absorbent core 4. Yes. And in the site | part in which the absorptive core 4 exists, neither the 1st elastic member 71a and the 2nd elastic member 72a exist substantially. As a result, the gathers formed in the second region 7B and the third region 7C are located between the left and right side edges of the diaper 1 and the left and right side edges of the absorbent core 4, and the absorbent core 4 is present. The position is substantially free of gathers. Thereby, the part in which the absorbent core 4 is present even in the worn state does not shrink the outer packaging material 11 due to the contraction of the first elastic member 71a and the second elastic member 72a, and the diaper 1 is also visually improved. Also, the absorption performance is good. However, the present invention is not limited to this configuration, and the first elastic member 71a and the second elastic member 72a may be disposed over substantially the entire circumference in the width direction of the diaper 1.

  As each elastic member in the diaper 1 of the present embodiment, a stretchable material such as natural rubber, polyurethane resin, urethane foam resin, stretchable nonwoven fabric or hot melt stretchable member is used as a thread (thread rubber) or a strip (flat). (Rubber), net (net) or film is preferably used.

  Thus, in the diaper 1 of the present embodiment, the average value of the pressure when the diaper 1 is worn in the second region 7B is 0.9 to 1.8 kPa, and the maximum value is 2.5 kPa or less. The second region 7B is preferably formed at a portion that abuts a portion (hereinafter also referred to as an iliac region) from the wearer's iliac crest to the upper anterior iliac spine when the diaper 1 is worn. The iliac crest and superior anterior iliac spine are anatomical terms. The iliac crest is a part indicated by 9a in FIG. 4, and the superior anterior iliac spine is a part indicated by 9b in FIG. Conventionally, in order to prevent slipping while wearing a pants-type diaper, particularly to prevent slipping while wearing a pants-type disposable diaper for infants, tightening an elastic member disposed in the waist opening It has been considered effective to increase the pressure and bring the pant-type diaper into close contact with the wearer's body through the waist opening (for example, see Patent Document 2 described above). However, as a result of the study by the present inventors, in order to effectively prevent slippage during wearing of the pants-type diaper, the tightening pressure of the waist opening, that is, the tightening pressure of the first region 7A in this embodiment is set. It has been found that it is more effective to increase the tightening pressure of the second region 7B, which is a part of the diaper corresponding to the iliac region of the wearer, than to increase it. The reason for this is that wearers, particularly infants, have their waists protruding as a physical feature, so if the tightening pressure of the waist opening that abuts the protruding belly is increased, the tightening pressure is high. This is because the waist opening is gradually narrowed down and the waist opening is shifted down to a site where the abdomen becomes thinner.

FIG. 5 shows a state in which the baby's body is regarded as a cone. In the figure, θ represents an angle formed by a perpendicular to the tangent line at the waist (point A) and a horizontal line toward the center of the body, F represents a tightening force of the elastic body, P represents a frictional force caused by F, f1 indicates a slip-off force caused by F, and f2 indicates a vertical drag. Here, since f1 = Fsinθ and P = νN = νf2 = νFcosθ (ν represents a friction coefficient), the downward slipping force Z at the point A is represented by the following equation.
Z = f1−P = Fsinθ−νFcosθ = F (sinθ−νcosθ)
From this equation, it can be understood that when the waist portion is in a state where slipping occurs, the slipping force increases as the tightening force (F) increases.

  As described above, the average value of pressure when the diaper 1 is worn in the second region 7B is 0.9 to 1.8 kPa, and the maximum value is 2.5 kPa or less. When the average value of the pressure when the diaper 1 is worn in the second region 7B is less than 0.9 kPa, it is difficult to fix the second region 7B of the diaper 1 to the wearer's iliac region, and as a result, the diaper 1 Will fall off and the external appearance of the diaper 1 in a wearing state will fall very much. In particular, the looseness at the crotch part C of the diaper 1 becomes prominent and also causes leakage of urine and feces. On the other hand, when the average value of the pressure when the diaper 1 is worn in the second region 7B is more than 1.8 kPa, the wearer's body is excessively tightened, and the wearing operation of the diaper 1 becomes difficult. In addition, it is not preferable that there is a part where the mounting pressure is locally high from the viewpoint of preventing the trace of the elastic member from remaining on the skin by wearing. From this viewpoint, it is important that the maximum value of pressure when the diaper 1 is worn is 2.5 kPa or less. From the viewpoint of more effectively preventing the diaper 1 from slipping off and further improving the appearance of the diaper 1 and the wearing operation of the diaper 1, the average value of the pressure when the diaper 1 is worn in the second region 7B. Is preferably 0.8 to 1.6 kPa, more preferably 0.9 to 1.5 kPa. Further, from the viewpoint of further preventing the marks of the elastic member from remaining on the skin by wearing, the maximum value of the pressure when wearing the diaper 1 is preferably 2.0 kPa or less, and more preferably 1.8 kPa or less. .

  The average value and the maximum value of the pressure when the diaper 1 is worn in the second region 7B can be controlled by adjusting the material, thickness, elongation rate, or arrangement interval of the first elastic member 71a, for example.

  The average value and the maximum value of the pressure when the diaper 1 is worn in the second region 7B are determined by attaching the diaper 1 to a cylinder having a circumference of 500 mm, and a wearing pressure measuring device (contact pressure measuring device manufactured by AIM Techno Co., Ltd.). (AMI3037-2)). The specific measurement method is as follows.

[Method for measuring pressure in second region 7B]
Using an air pack of φ = 15 mm, set the air pack so that the center of the air pack is positioned on the boundary line between the second region and the first region, and measure the mounting pressure (P1). The position of the diaper width direction in which the air pack is set is approximately the center between the left and right side edges of the diaper and the left and right side edges of the absorbent core 4 (see FIG. 3). Subsequently, the center of the 5 mm air pack is moved in the diaper length direction, and the mounting pressure (P2) is measured. Similarly, measurement is performed at intervals of 5 mm to obtain P3, P4, P5,. Measurement of P1 to Pn is performed within the range of the second region. P1 to Pn are measured from a total of four points, two on each of the left and right sides on the ventral part and the dorsal part, and are obtained from the average values thereof. The average value of pressure when the diaper 1 is worn is obtained from the obtained average value of P1 to Pn, and the maximum value of pressure when the diaper 1 is worn is obtained from the maximum value of P1 to Pn.

  The reason why the circumference of the cylinder is set to 500 mm is that the average length around the belly of an infant who is a main subject wearing the diaper 1 of the present embodiment is approximately 500 mm. The length of the abdomen around here is an average value of the abdomen circumference measured in the standing position and the sitting position in consideration of the change in the circumference of the abdomen when the posture of the infant changes.

  A portion from the wearer's iliac crest to the upper anterior iliac spine has a certain width, and the second region 7B of the diaper 1 is fixed to the portion within the range of the width, so that the diaper 1 is slipped off. Can be effectively prevented. From this viewpoint, in the diaper 1 of this embodiment, the length of the side seal portion S is 90 to 140 mm. When this width is 95 to 135 mm, particularly 95 to 130 mm, the diaper 1 can be prevented from slipping off more effectively, and the appearance of the diaper 1 in the worn state and the wearing operation of the diaper 1 (easy to cut) Etc.) can be further improved.

  In the diaper 1, in addition to the length of the side seal portion S, the total length L in the longitudinal direction in the expanded state of the diaper 1 is 440 to 530 mm. As described above, as long as the second region is formed in a portion that abuts on the portion from the wearer's iliac crest to the upper anterior iliac spine, the upper portion (first region) is the diaper. There is no effect on the slip-off, and conversely, if the tightening pressure in the first region is strong, the first region portion is lowered to the vicinity of the iliac bone. If the length of the first region is longer than necessary, a portion that is likely to be displaced becomes longer, which is not preferable. Therefore, it is desirable to shorten the length of the first region in the longitudinal direction of the diaper as much as possible from the viewpoint of preventing slipping off and enhancing the “clean feeling” when the diaper is worn. However, when a diaper is considered as clothing, the first region needs a certain length. As a result of various studies by the inventors, the overall length L in the longitudinal direction of the diaper 1 in the unfolded state is set to 440 to 530 mm, so that “feeling of security” and “clean feeling” as clothes when wearing the diaper. The present inventors have found that a diaper having “slip-off prevention” can be obtained by bringing the second region into contact with the site from the iliac crest to the superior anterior iliac spine without damaging the scapula. In order to further improve “feeling of security”, “clean feeling” and “preventing slip-off” at the time of wearing, it is preferable that the total length L in the longitudinal direction in the deployed state of the diaper 1 is 450 to 520 mm. More preferably, it is 515 mm.

  In a state where the diaper 1 is worn, the relationship between the size of the diaper 1 and the wearer's physique in order for the second region 7B to contact the site from the wearer's iliac crest to the upper anterior iliac spine is important. For example, when an infant who is a main wear target person of a pants-type diaper is considered, in the unfolded state of the diaper 1, the center position of the second region 7B of the abdominal side A (center position along the longitudinal direction of the diaper 1) and the diaper 1 The distance K1 to the longitudinal center line CL of the diaper 1 is preferably 180 to 220 mm, and in the unfolded state of the diaper 1, the center position of the second region 71 of the back side B (the center position along the longitudinal direction of the diaper 1) ) And the longitudinal center line CL of the diaper 1 is preferably set to 180 to 220 mm, whereby the second region 7B can be successfully brought into contact with the wearer's iliac region. This value is determined by carrying out body measurements of about 350 infants who are the main wearees of pants diapers. Specifically, as shown in FIG. 6, the abdominal side left and right center point at the horizontal position height of the upper anterior iliac spine is the upper anterior iliac spine height front center, and the dorsal side is the upper anterior iliac spine height. As the posterior center, the length from the center of the superior anterior iliac spine to the center of the posterior center of the superior anterior iliac spine via the crotch is defined as the longitudinal length of the superior anterior iliac spine. The numerical value obtained by adding the necessary length in consideration of the thickness of the diaper material is divided into two. By setting the distances K1 and K2 to 185 to 215 mm, particularly 190 to 215 mm, the second region 7B can be brought into more successful contact with the wearer's iliac region.

  Although the 2nd field exists in ventral part A and back part B, the pressure at the time of wearing in ventral part A and dorsal part B does not need to be exactly the same. That is, the average value of the pressure at the time of wearing of the second region in the ventral side A and the back side B is 0.9 to 1.8 kPa, and the maximum pressure at the time of wearing in the ventral side A and the back side B As long as the value satisfies 2.5 kPa or less, the material, thickness, elongation rate, and arrangement interval of the elastic body may be different in the ventral side A and the back side B. However, if the configurations of the second regions of the ventral portion A and the dorsal portion B are excessively different, the portions where the left and right side portions of the longitudinal front and rear end portions of the outer packaging material 11 are joined to each other are It may shift to either, and a defect may occur in the appearance of the diaper 1. Therefore, the ratio of (A−B) / A is within 30% when A is the larger average value of the pressure when wearing the second region in the ventral region A and the dorsal region B, and B is the smaller average value. It is preferable that

  In the present invention, the longitudinal center line CL of the diaper 1 is joined to the side edges A1, A2 of the ventral side A of the diaper 1 and the side edges B1, B2 of the back side B without substantially shifting. In this case, it means a straight line along the diaper width direction passing through the midpoints of A1 and B1 in the unfolded state of the diaper 1 (see FIG. 3). Unlike this, for example, as shown in FIGS. 7A and 7B, both side edges A1, A2 of the ventral side A are not joined to both side edges B1 ′, B2 ′ of the back side B, In the case of joining at B1 and B2 which are positions inward in the longitudinal direction from both side edges B1 ′ and B2 ′, assuming that there is no region from B1 and B2 to B1 ′ and B2 ′, As before, a longitudinal centerline of the diaper is defined.

  As described above, in the diaper 1 according to the present embodiment, the diaper 1 is fixed to the wearer's body mainly by the tightening force of the first elastic member 71a disposed in the second region 7B. In other words, unlike the conventional pants-type diaper, the fastening force by the waist elastic member 51 mainly disposed in the first region 7A fixes the diaper 1 to the wearer's body in the diaper 1 of the present embodiment. It is not the main means for. On the contrary, it has been confirmed by the present inventors that if the tightening force of the waist opening 5 is increased, the diaper 1 is displaced. From this viewpoint, in the diaper 1 of the present embodiment, the average value of the pressure in the first region 7A when wearing the diaper is set to 0.3 to 1.2 kPa, which is a lower value than that of the conventional pants-type diaper. It is preferable. This pressure needs to be set lower than the pressure in the second region 7B when the diaper is worn. In addition, by setting the pressure in the first region 7A when wearing the diaper within the above range, there is an advantage that the waist opening 5 can be easily expanded when the diaper 1 is worn, and the wearing operation can be easily performed. If it is 0.3 kPa or less, the natural length of the diaper 1 before wearing becomes large, and there may be a problem such as poor appearance when viewed as clothes.

  When the average value of the pressure in the first region 7A when wearing the diaper is more preferably 0.4 to 1.2 kPa, and even more preferably 0.5 to 1.1 kPa, the slipping of the diaper 1 is further effective. Can be prevented. The average value of the pressure in the first region 7A can be measured by the same method as the average value of the pressure in the second region 7B described above. That is, a cylinder having a circumferential length of 500 mm is inserted (attached) into the diaper 1, and the attachment pressure (P1) is measured by positioning the center of the air pack (φ = 15 mm) of the attachment pressure measuring device in the first region 7A. The position in the diaper width direction is approximately the center between the left and right side edges of the diaper and the left and right side edges of the absorbent core. Subsequently, the center of the 5 mm air pack is moved in the diaper length direction, and the mounting pressure (P2) is measured. Similarly, measurement is performed at intervals of 5 mm to obtain P3, P4, P5,. Measurement of P1 to Pn is performed within the range of the first region 7A. P1 to Pn are measured from a total of four points, two on each of the left and right sides on the ventral part and the dorsal part, and are obtained from the average values thereof. The average value of the pressure when the diaper 1 is worn is obtained from the obtained average value of P1 to Pn. The average value of the pressure in the first region 7A can be controlled, for example, by adjusting the material, thickness, elongation rate, or arrangement interval of the waist elastic member 51.

  In the diaper 1 of the present embodiment, the average value of the pressure in the third region 7C when the diaper is worn is preferably 0.2 to 1.0 kPa, more preferably 0.3 to 0.8 kPa. As a result, the diaper 1 can be brought into close contact with the wearer's body with an appropriate pressure, and liquid leakage can be effectively prevented. This pressure needs to be set lower than the pressure in the second region 7B when the diaper is worn. When the diaper 1 is worn, the third region 7C comes into contact with the lower region (lower abdomen) of the wearer's iliac region. This pressure can be obtained by a method similar to the method for obtaining the average value of the pressure when the diaper is mounted in the first region 7A and the second region 7B. That is, the diaper 1 is mounted on a cylinder having a circumferential length of 500 mm, an air pack having φ = 15 mm is used, and the center of the air pack is positioned on the boundary line between the third region and the second region, and the mounting pressure ( P1) is measured. The position of the diaper width direction in which the air pack is set is approximately the center between the left and right side edges of the diaper and the left and right side edges of the absorbent core 4. Subsequently, the center of the 5 mm air pack is moved in the diaper length direction, and the mounting pressure (P2) is measured. Similarly, measurement is performed at intervals of 5 mm to obtain P3, P4, P5,. Measurement of P1 to Pn is performed within the range of the second region. P1 to Pn are measured from a total of four points, two on each of the left and right sides on the ventral part and the dorsal part, and are obtained from the average values thereof. The average value of the pressure when the diaper 1 is worn is obtained from the obtained average value of P1 to Pn.

  As already described, in the first region 7A and the third region 7A, the pressure when the diaper is worn is made lower than that in the second region. It is particularly preferable that the magnitude relationship between these three is as follows. That is, when comparing the pressure when wearing the diapers in the first region 7A to the third region 7C, the pressure in the second region 7B is the highest, then the pressure in the first region 7A is high, and the pressure in the third region 7C is The lowest is preferred. Providing such an order in the pressure of each part not only effectively prevents the diaper 1 from slipping off during wearing, but also the diaper 1 adheres to the wearer's body without a sense of incongruity, and liquid leakage is effective. Is prevented.

  In the diaper 1, it is preferable that the pressure of the leg opening 6 at the time of wearing the diaper is 1.0 to 2.4 kPa, particularly 1.2 to 2.2 kPa. When the pressure of the leg opening 6 at the time of wearing the diaper is within the above range, the opening end of the leg opening 6 fits the wearer's buttocks appropriately, and the liquid leakage from around the leg of the wearer is effective. Can be prevented. Moreover, even if the weight in the crotch of the diaper 1 increases due to urination / defecation during use, the absorbent core is prevented from separating from the wearer's body in the crotch, and the appearance of the diaper 1 being worn is also improved. Reduction and leakage of urine and feces are prevented. As a result, effects such as being able to keep the diaper 1 in a worn state in a good state can be obtained.

  The mounting pressure at the leg opening is measured by the following method. The device / air pack is the same as the waist opening measurement. A cylinder having a circumferential length of 300 mm is inserted into (attached to) the leg opening 6 of the diaper 1, and six points are measured at intervals of 50 mm in the circumferential direction at the portion where the elastic members 61 a and 61 b are arranged. When there are a plurality of elastic members 61a and 61b, measurement is performed at the center point of the width of the region where the elastic members are arranged. The average value of 12 points on the right foot and left foot is taken as the mounting pressure of the leg opening 6. For those where the leg elastic members 61a and 61b are not completely or partially, the mounting pressure in the region where the side cuff elastic members 81 are disposed in the corresponding portion is used as the mounting pressure of the leg opening. The reason why the circumference of the cylinder is 300 mm is that the average length of the buttocks (foot circumference) of the infant who is the main subject wearing the diaper 1 of the present embodiment is approximately 300 mm.

  As mentioned above, although this invention was demonstrated based on the preferable embodiment, this invention is not restrict | limited to the said embodiment. For example, in the diaper 1 of the embodiment, the first elastic member 71a or the second elastic member 72a is disposed only between the left and right side edges of the diaper 1 and the left and right side edges of the absorbent core 4. However, the elastic members 71a or 72a may be partially overlapped only on the left and right side edges of the absorbent core 4, or may be arranged over the entire length of the diaper in the width direction. In this case, a force of contraction by the first or second elastic member acts on the outer packaging material 11 in a portion overlapping the absorbent core 4. However, even in such a case, the outer packaging material 11 located in the region where the absorbent core 4 is disposed is adhered to the absorbent core 4 with an adhesive, and thus the elasticity of the absorbent core 4 is utilized. The shrinkage of the member can be suppressed, and wrinkles can be prevented from occurring in the outer packaging material 11 in the portion where the absorbent core 4 is disposed. Also, the first elastic member 71a or the second elastic member 72a sandwiched and fixed between the outer layer and inner layer nonwoven fabrics 12 and 13 should be hardly fixed to the nonwoven fabrics 12 and 13 only at the portion where the absorbent core 4 is arranged. Also, it is possible to prevent wrinkles from occurring in the outer packaging material 11 in the portion where the absorbent core 4 is disposed.

  Moreover, how to arrange the elastic members 71a is not limited to the above-described embodiment. For example, as shown in FIG. 8, a plurality of first elastic members 71a are arranged over the entire width direction of the diaper in the ventral side A, and The central portion of the first elastic member 71a may be curved in a convex shape toward the crotch portion C of the diaper. Due to the curved shape of the first elastic member 71a, when the diaper 1 is worn, the pressing force of the first elastic member 71a stably acts on the wearer's belly. In particular, the diaper can be more easily fitted to the infant's body shape with the abdomen around. As a result, the vertical displacement of the diaper is less likely to occur.

  Furthermore, as shown in FIG. 9, a plurality of first elastic members 71 a are arranged on the ventral side A across the entire width direction of the diaper and are located near the crotch C of the diaper. 71a may be curved in a convex shape toward the crotch portion C. In this case, it is preferable to increase the degree of curvature of the first elastic member 71a closer to the crotch part C. With such an arrangement of the first elastic member 71a, a wide range around the abdomen can be covered with the first elastic member 71a. As a result, in addition to the contraction in the left-right direction, the force of contraction in the up-down direction is generated, so that it is possible to prevent the diaper from being displaced in the up-down direction and raise the center part in the width direction of the diaper upward. .

  In the outer packaging material 11, only one of the inner layer nonwoven fabric 13 and the outer layer nonwoven fabric 12 can be a water repellent nonwoven fabric. In addition, when the side cuff 8 can ensure sufficient leak-proof property, a water-permeable nonwoven fabric can be used for both the inner layer nonwoven fabric 13 and the outer layer nonwoven fabric 12.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the scope of the present invention is not limited to such examples.
[Example 1]

[Example 1 and Comparative Examples 1 to 5]
The underpants type diaper shown in FIG. 1 thru | or FIG. 3 was produced. The surface sheet 2 in the absorbent main body 10 was composed of a hydrophilic air-through nonwoven fabric having a basis weight of 25 g / m ² . The back sheet 3 was composed of a polyethylene sheet having a basis weight of 20 g / m ² . Further, the outer layer nonwoven fabric 11 in the outer packaging material 11 was composed of a water-repellent air-through nonwoven fabric having a basis weight of 25 g / m ² , and the inner layer nonwoven fabric was composed of a water-repellent spunbonded nonwoven fabric having a basis weight of 18 g / m ² . The pressure generated by each elastic member was adjusted by changing the type of elastic material and the elongation rate. Table 1 shows each value in the obtained diaper.

The obtained diapers were attached to three 1 to 2 year old infants and evaluated as follows. The results are shown in Table 1.
(1) Operability when wearing (easy to put diapers on)
○: Easy to fold △: Slightly fragile ×: Slightly difficult (2) Position shift of the second area 60 minutes after mounting ○: No position shift △: Slight position shift ×: With position shift (3) 60 minutes after mounting Misalignment of waist opening of ○: No misalignment Δ: Slight misalignment ×: Miss position misalignment (4) Rubber marks in the body part corresponding to the second region 60 minutes after wearing ○: No rubber marks Δ: Slightly There is a rubber mark ×: Rubber mark (5) Diaper appearance immediately after wearing ○: Clean △: It is easy to clear ×: Not clear (6) Diaper appearance after 60 minutes of wearing ○: Clean Yes: Easily refreshed X: Not refreshed

  Further, with respect to the diapers of Example 1 and Comparative Example 5, the main effects of the present invention are “presence / absence of rubber marks in the body part corresponding to the second region 60 minutes after wearing” and “waist opening 60 minutes after wearing” The presence or absence of misalignment was evaluated in detail. Twenty-five each of these diapers were attached to infants aged 11 to 37 months, and the mother was asked to investigate whether or not he / she would support “difficult rubber marks” and “difficult to shift”. The results are shown in Table 2.

  As is apparent from the results shown in Table 1, the diaper of Example 1 is easy to flake, and it is difficult for the diaper to slip off, and the appearance of the diaper is good immediately after wearing and after a predetermined time has elapsed after wearing. I understand that. On the other hand, it can be seen that the diaper of Comparative Example 1 has a long overall length and a long side seal portion, and is inferior in diaper appearance. Moreover, since the part above the iliac bone is long, the waist part tends to slip off. It can be seen that the diaper of Comparative Example 2 has a high average value of the mounting pressure in the second region and is difficult to break. Rubber marks are also easily attached. It can be seen that the diaper of Comparative Example 3 has a high maximum value of the mounting pressure in the second region and is difficult to break. Rubber marks are also easily attached. It can be seen that the diaper of Comparative Example 4 has a high average value of the wearing pressure in the first region, and the waist portion is likely to slip off. Also, it is hard to break.

  As is clear from the results shown in Table 2, the diaper of Example 1 has received very high support from the mother regarding the evaluation items of “difficult to leave rubber marks” and “difficult to cause displacement”. I understand. On the other hand, in the diaper of Comparative Example 5, the mother's support is only about half.

It is a perspective view which shows one Embodiment of the underpants type disposable diaper of this invention. It is a disassembled perspective view which shows the state before assembling the diaper shown in FIG. It is a top view which shows the expansion | deployment state of the outer packaging material in FIG. It is explanatory drawing which shows an iliac bone. It is explanatory drawing which shows the calculation method of the slipping-off force in a wearer's waist part. It is explanatory drawing which shows the measuring method of upper anterior iliac spine height front and back length. Fig.7 (a) is a perspective view which shows another embodiment of the diaper of this invention, FIG.7 (b) is a top view which shows the unfolded state of the diaper shown in Fig.7 (a). It is a top view in the unfolded state which shows another embodiment of the diaper of this invention. It is a top view in the unfolded state which shows another embodiment of the diaper of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pants type disposable diaper 2 Top sheet 3 Back sheet 4 Absorbent core 5 Waist opening 6 Leg opening 7A 1st area | region 7B 2nd area | region 7C 3rd area | region 7D 4th area | region

Claims (7)

A pants-type disposable diaper having a waist opening and a pair of leg openings,
The total length of the unfolded state diaper in the longitudinal direction is 440 to 530 mm, and the unfolded state diaper side seal portion has a length of 90 to 140 mm.
An area from the waist opening to the leg opening in the bonded diaper is drawn with a virtual dividing line that is equally divided into four in the longitudinal direction, and the first area, the second area, and the third area in that order from the waist opening side. When the fourth region is virtually considered, the average value of the pressure when wearing the diaper of the second region is 0.9 to 1.8 kPa and the maximum value is 2.5 kPa or less, and the first The region and the third region are pants-type disposable diapers in which the pressure when wearing the diaper is lower than that of the second region.   The pants-type disposable diaper according to claim 1, wherein, in the first region to the third region, the pressure when the diaper is worn is highest in the second region, then high in the first region, and lowest in the third region.   The underpants type disposable diaper of Claim 1 or 2 with which the average value of the pressure at the time of diaper wear of a 1st area | region is 0.3-1.2kPa.   The underpants type disposable diaper in any one of Claim 1 thru | or 3 with which the average value of the pressure at the time of diaper wear of a 3rd area | region is set to 0.2-1.0kPa.   The elastic member is distribute | arranged by the extended state along the said leg opening part, The pressure at the time of diaper wearing of this leg opening part is set to 1.0-2.4kPa. Pants-type disposable diapers.   The pants-type disposable diaper according to any one of claims 1 to 5, wherein the second region mainly exists between the left and right side edges of the diaper and the left and right side edges of the absorbent body. The pants-type disposable diaper according to any one of claims 1 to 6, wherein the second region is formed at a portion that comes into contact with the upper anterior iliac spine from the wearer's iliac crest when the diaper is worn.

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