JP3949020B2 - Absorbent articles - Google Patents

Description

【００５４】
表１に示す結果から明らかなように、実施例のナプキンは装着感が良好であり、ヨレの発生が防止されていることが判る。これに対して比較例のナプキンは、装着感が良好でなく、しかもヨレが発生し易いことが判る。
【００５５】
【発明の効果】
本発明の吸収性物品は、薄型であるにもかかわらず十分な吸収性を有し、また柔らかでクッション感が良く、快適な装着感があり、ヨレが少ない。従って本発明の吸収性物品は、長時間の着用に適したものとなる。
【図面の簡単な説明】
【図１】本発明の吸収性物品の一実施形態としての生理用ナプキンを示す斜視図である。
【図２】図１におけるII−II線断面図である。
【図３】トップシートの要部を拡大して示す模式図である。
【符号の説明】
１ 生理用ナプキン（吸収性物品）
２ トップシート
３ バックシート
４ 吸収体
５ 中間シート[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an absorbent article such as a sanitary napkin or a panty liner, and more particularly relates to an absorbent article having a thin, soft feel and a comfortable wearing feeling and little twist.
[0002]
[Prior art and problems to be solved by the invention]
Conventionally, in absorbent articles such as sanitary napkins and panty liners, in order to realize a thin product with little discomfort when worn, as an absorbent that absorbs the user's body fluid, compressed pulp or two paper sheets Thin absorbers such as polymer sheets with a superabsorbent polymer sandwiched between them have been used. However, since a thin absorbent body is inferior in terms of liquid return after absorption and prevention of twisting, various absorbent articles in which an intermediate sheet is disposed between the top sheet and the absorbent body have been proposed.
[0003]
For example, the present applicant previously described in Japanese Patent Application Laid-Open No. 10-216172, the absorbent portion is made of an absorbent body having an absorbent polymer and an elastic material, the fiber orientation of the heat-fusible fiber is randomized, and the bending rigidity is at a certain level. As a result, an absorbent article that has achieved warpage prevention and reduced discomfort was proposed. However, this elastic material has the same characteristics in any direction since the fiber orientation is constant three-dimensionally. Therefore, when trying to prevent the twist effectively, the sense of incongruity tends to increase, and when trying to suppress the sense of incongruity, the twist tends to occur.
[0004]
JP-A-11-192259 discloses an absorbent article having an absorbent body between a liquid-permeable top sheet and a liquid-impermeable back sheet, and a second sheet disposed between the top sheet and the absorbent body. Is described. In this second sheet, fibers having a fiber diameter of 4 to 18 denier and a length of 5 to 100 mm are fused at the intersection to maintain the web form, and 12 g / cm.²Thickness under load is 0.3-3.0mm, average density is 0.01-0.05g / cm^ThreeIt is. The density of the top sheet is higher than that of the second sheet. This second sheet is used to improve the spot sheet absorbency and absorption rate of the top sheet and to improve the dry touch property. However, this second sheet is 12g / cm²In other words, it maintains a certain thickness even under a relatively high load, and thus exhibits a very hard texture and does not have good cushioning properties. Therefore, it cannot be said that it is suitable for long-time wearing.
[0005]
Japanese Patent Application Laid-Open No. 8-24289 describes a bodily fluid absorbing contact material comprising a surface material made of cotton and an absorbent material made of a hydrophilic nonwoven fabric. This absorbent material mainly comprises hollow synthetic fibers composed of fibers having an average fiber diameter of about 1 to 3 denier and having an average fiber diameter of about 4 to 8 denier in order to provide an overall elastic return to deformation. Yes. This bodily fluid absorbing material is intended to prevent the occurrence of twist caused by using a surface material made of cotton by using an absorbent material containing the hollow synthetic fiber. However, this bodily fluid absorbing material has no stiffness as a whole, and the cushioning property is not good. Furthermore, since the surface material is made of cotton, absorbed menstrual blood tends to stay on the surface material, and it is easy to give the user a very dirty impression. Therefore, it cannot be said that it is suitable for long-time wearing.
[0006]
Japanese Patent Application Laid-Open No. 63-109859 discloses an absorbent article having an absorbent containing hydrophilic fibers and a superabsorbent polymer, in which the absorbent is provided with an acquisition band and a storage band located around the acquisition band. The acquisition zone has a lower density and lower basis weight than the storage zone. In this absorbent article, the liquid is transferred from the acquisition zone to the storage zone so that the superabsorbent polymer contained in the storage zone does not cause gel blocking. However, since the low-density acquisition band forms part of the absorbent body and does not exist separately from the absorbent body, this absorbent article does not have high cushioning properties. Therefore, it cannot be said that it is suitable for long-time wear.
[0007]
Accordingly, an object of the present invention is to provide an absorbent article that is comfortable to wear with a soft feel without impairing absorbability, has little twist, and is suitable for long-time wearing.
[0008]
[Means for Solving the Problems]
  The present invention relates to an absorbent article including a liquid-permeable top sheet, a liquid-impermeable back sheet, and a liquid-retaining absorbent disposed between both sheets.
  A liquid-permeable intermediate sheet is disposed between the top sheet and the absorber, and the intermediate sheet contains 25 to 100% by weight of fibers having a fineness of 3.3 to 11 dtex, and two or more kinds of heat melts. The melting point mp of the heat-sealable component having the highest melting point among the fusion-bonding components including the adhesive-bonding fiber and constituting the heat-sealable fiber._maxAnd the melting point mp of the heat fusion component having the lowest melting point_minDifference with mp_max-Mp_minThe intermediate sheet is 30 to 60% of the thickness of the absorbent article, and the thickness of the intermediate sheet itself is 0.8 to 2 mm.
  The absorbent article has a thickness of 1.5 to 4 mm and a thickness change rate of 20% or more, and absorbs the L value (La) on the topsheet side before use and 2 g of defibrinated horse blood. The difference La-Lb from the L value (Lb) on the top sheet side afterThe
  Among the top sheet, the intermediate sheet, the absorber, and the back sheet, the thickness of the intermediate sheet is the largest.The above object is achieved by providing an absorbent article..
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described below based on preferred embodiments with reference to the drawings. FIG. 1 shows a perspective view of a sanitary napkin as an embodiment of the absorbent article of the present invention, and FIG. 2 shows a sectional view taken along line II-II in FIG.
[0010]
As shown in FIG. 1, the napkin 1 of this embodiment has a vertically long shape. The longitudinal front and rear ends of the napkin 1 have a smooth arc shape. The side edge in the center part in the vertical direction of the napkin 1 is slightly bound toward the inner side in the width direction. As shown in FIG. 2, the napkin 1 includes a liquid-permeable top sheet 2, a liquid-impermeable back sheet 3, and a liquid-retaining absorbent body 4 interposed between both sheets 2 and 3. . A liquid-permeable intermediate sheet 5 is disposed between the top sheet 2 and the absorber 4.
[0011]
The top sheet 2 and the back sheet 3 have substantially the same shape and form the outline of the napkin 1. On the other hand, the absorber 4 and the intermediate sheet 5 are slightly smaller than the top sheet 2 and the back sheet 3. The top sheet 2 and the back sheet 3 extend outward from the peripheral edges of the absorber 4 and the intermediate sheet 5, and the extended top sheet 2 and back sheet 3 are heat-sealed to each other. By this heat seal joining, a peripheral seal portion 6 having a closed shape is formed on the peripheral portion of the napkin 1.
[0012]
The intermediate sheet 5 is present in all the areas except the peripheral edge of the napkin 1, specifically, in an area surrounded by the peripheral seal portion 6, and is in contact with the top sheet 2. The absorber 4 is present in substantially the same region as the region where the intermediate sheet 5 is present and is in contact with the intermediate sheet 5.
[0013]
As shown in FIG. 2, in the napkin 1 of the present embodiment, the total thickness of the top sheet 2 and the intermediate sheet 5 occupies most of the total thickness of the napkin 1. Specifically, the sum of the thicknesses of the top sheet 2 and the intermediate sheet 5 is preferably 45 to 90%, particularly 55 to 90% of the total thickness of the napkin 1. Thereby, even if the thickness of the napkin 1 is reduced, the napkin 1 having a soft feel and a good wearing feeling can be obtained. The thickness of the napkin 1 itself is 1.5 to 4 mm, preferably about 2 to 3.5 mm from the viewpoint of reducing the uncomfortable feeling during use by making the napkin 1 thin.
[0014]
The sum of the thicknesses of the top sheet 2 and the intermediate sheet 5 may be different between the central part of the napkin 1 and the peripheral part of the napkin 1. Specifically, the thickness at the central portion is larger than that at the peripheral portion of the napkin 1 to increase the cushion feeling of the central portion, which is the most strongly crimped portion of the napkin 1, and the peripheral portion that contacts the inner crotch. It is preferable from the viewpoint of preventing a sense of incongruity in For example, the sum of the thicknesses of the top sheet 2 and the intermediate sheet 5 at the central portion of the napkin 1 is 45 to 90% of the thickness of the entire napkin, and the sum of the thicknesses of the top sheet 2 and the intermediate sheet 5 at the peripheral portion is the entire napkin. It is preferable to set it as 25 to 80% with respect to the thickness.
[0015]
  Of the top sheet 2 and the intermediate sheet 5, the intermediate sheet 5 is particularly thick. Specifically, the thickness of the intermediate sheet 5 is the largest among the top sheet 2, the intermediate sheet 5, the absorber 4, and the back sheet 3 that are main members constituting the napkin 1. As the intermediate sheet 5, a bulky material that is soft and has a high compression recovery property is used. As the intermediate sheet 5 having such characteristics, the thickness of the napkin 1 is as a whole.Of 3What is 0 to 60% is used. Thereby, even if the thickness of the whole napkin 1 is reduced, the touch of the top sheet 2 becomes good, and the napkin 1 having a soft feeling and a good wearing feeling can be obtained. The thickness of the intermediate sheet 5 is measured by the method described later.
[0016]
  As the intermediate sheet 5 having the above-mentioned characteristics, it is effective to use a nonwoven fabric containing 25 to 100% by weight, preferably 50 to 100% by weight of fibers having a fineness of 3.3 to 11 dtex, preferably 4 to 9 dtex. Found by the inventors. The fibers having the fineness in the above-mentioned range belong to a relatively thick class among the fibers used as the constituent material of the absorbent article. A non-woven fabric that includes such a thick fiber in a range of the above-mentioned range of fibers has a high recovery property against compression. By using such a non-woven fabric in such a thickness as to be within the above-mentioned range with respect to the thickness of the napkin 1, the top sheet 2 has a good touch even if the entire thickness of the napkin 1 is reduced. Further, the napkin 1 can be made soft and have a good cushion feeling. Although it depends on the total thickness of the napkin 1 and the thickness of the top sheet 2, the nonwoven fabric itself, that is, the thickness of the intermediate sheet 5 itself.0. By making the thickness 8 to 2 mm, this effect can be made more remarkable.
[0017]
In order to further improve the cushioning properties, it is effective to use fibers having high elasticity. From this viewpoint, the fiber having the fineness in the above-mentioned range is preferably a core-sheath type composite fiber having a highly elastic fiber as a core. Specific examples thereof include core-sheath composite fibers having a core made of polyethylene terephthalate and a sheath made of polyethylene.
[0018]
The cushioning property of the nonwoven fabric can be further improved by using crimped fibers. In particular, it is effective to use a three-dimensionally crimped fiber.
[0019]
On the other hand, in order to further increase the softness of the intermediate sheet 5, followability to compression is required. It has been found that it is effective to weaken the bonding between the fibers in the nonwoven fabric constituting the intermediate sheet 5 in order to improve the followability to compression. As a method of weakening the bonding, there are a method of reducing the number of bonding points of fibers, a method of weakening the bonding site between fibers, and the like. In particular, (1) means for using a fiber having an increased core component ratio of the core-sheath type composite fiber as the fiber having a fineness of 3.3 to 11 dtex so as not to strengthen the bond between the fibers; Means not to strengthen the bond between fibers by performing heat treatment at a temperature not exceeding a certain range with respect to the melting point of the fiber, and (3) blending two or more kinds of fibers containing fusion components having different melting points. However, a means for producing a fiber that is likely to be fused or a fiber that is unlikely to occur is preferable. According to the means (1) to (3), although the fiber network structure itself is dense, the mobility of the network is improved, so that the effect of reducing the resistance of the nonwoven fabric is exhibited. Further, since the recoverability of the fiber itself is not impaired, an effect of maintaining the recoverability is also exhibited. The ratio of the core-sheath component of the core-sheath type composite fiber by the means of (1) to (3), the degree of fiber fusion, and the melting point of the fusion component are the melting point in the non-woven fabric production line by observing the fiber cross section with an electron microscope. It can be confirmed by means such as a change in the hardness of the nonwoven fabric when reheated at a temperature higher by about 30 ° C., and observation of the endothermic peak of the fusion component by DSC.
[0020]
Thus, by using a highly recoverable fiber having the fineness described above, that is, a thickness of 3.3 to 11 dtex, and forming a structure having a high followability to compression, the recoverability to compression is high and flexible. A nonwoven fabric having a cushion feeling can be formed. Examples of non-woven fabrics configured in this manner include (1) a core-sheath type composite fiber as a fiber having a fineness of 3.3 to 11 dtex, and the weight ratio of the core component to the sheath component of the core-sheath type composite fiber is : Nonwoven fabric with sheath = 55: 45-80: 20, (2) Nonwoven fabric formed by heat treatment in the range of mp to mp + 20 ° C. with respect to the melting point mp of the constituent fibers, and (3) Two or more types of heat fusion The melting point mp of the heat-sealable component having the highest melting point among the fusion-bonding components including the adhesive-bonding fiber and constituting the heat-sealable fiber._maxAnd the melting point mp of the heat fusion component having the lowest melting point_minThe difference from mp_max-Mp_minIs above 5 ° C, especially7A non-woven fabric manufactured by the air-through method is mentioned. Since the purpose of the heat-fusible fiber used is to create a network structure, the thickness of the fiber may be at a level normally used. However, it is more preferable to use a material having a large fineness in order to develop the above-described recoverability.
[0021]
In the napkin 1 using the nonwoven fabric formed by the above-mentioned means, the rate of change in thickness is 20% or more, preferably 20 to 60%, more preferably 30 to 50%. Since the napkin 1 formed in this manner has little resistance to compression and good followability to compression, a soft feel can be obtained during use, and the wearing feeling can be improved. The thickness of the napkin 1 itself is as described above. Furthermore, in the napkin 1 using the nonwoven fabric formed by the above-mentioned means, the repulsive force at the time of 40% compression is 5 to 20 cN / cm from the viewpoint of resistance to compression and followability.², Especially 7-18cN / cm²It is preferable that In the case of the intermediate sheet 5 alone, the repulsive force at 40% compression is 2.5 to 24.5 cN / cm.², Especially 5-20 cN / cm²It is preferable that Further, in the napkin 1, it is preferable that the bending rigidity value is 10 cN · cm / cm or less, particularly 2 to 7 cN · cm / cm, from the viewpoint of low discomfort and difficulty. As a means for reducing the bending rigidity value, it is preferable to reduce the fixing between the members of the napkin 1. Specifically, it is preferable to apply an adhesive such as hot melt used for fixing between the members at intervals.
[0022]
The repulsive force and the bending stiffness are values obtained by the apparatus and method according to KES (Kawabata Evaluation System), “Standardization and analysis of texture evaluation (2nd edition)”, Kyuo Kawabata, Japan Textile Machinery Society, Texture measurement Measured according to the methods described on pages 27 to 28 and pages 33 to 34 of the Standardization Research Committee (issued July 10, 1980). KES-FB3 (COMPRESSION TESTER) is used to measure the repulsive force, and the compression area is 2cm.²A circular plane, the compression rate is 20 μm / second, and the initial thickness is 0.49 cN / cm.²(0.5 gf / cm²). KES-FB2 (PURE BENDING TESTER) is used for the measurement of the bending stiffness, and the length in the longitudinal direction of the sample is set to 60 mm, and is measured at the center in the width direction.
[0023]
The rate of change of the thickness of the napkin 1 is T for the thickness of the napkin 1 under a load of 10 cN and T for the initial thickness.₀Then,
(T₀-T) / T₀× 100
It is a value defined by. T and T₀Uses the measured value by KES-FB3 as it is.
[0024]
The thickness of the intermediate sheet 5 and the thicknesses of the top sheet 2 and the absorber 4 described later are measured by the following methods. The napkin 1 is cut in the width direction. For cutting, Feather S single blade (# FAS-10) is used. The cut napkin 1 is compressed to a thickness corresponding to the initial thickness. Under this condition, the thicknesses of the top sheet 2, the intermediate sheet 5 and the absorber 4 on the cut surface are measured. A KEYENCE microscope (VH-7000) is used for the measurement.
[0025]
The nonwoven fabric constituting the intermediate sheet 5 is bulky as described above. Specifically, the density is 0.02 to 0.1 g / cm.^Three, Especially 0.03-0.08 g / cm^ThreeIt is preferable that Moreover, the basis weight is 30-80 g / m.², Especially 40-60g / m²It is preferable that The density of the nonwoven fabric is calculated by dividing the basis weight by the thickness. The method for measuring the thickness of the nonwoven fabric (intermediate sheet 5) is as described above.
[0026]
Since the nonwoven fabric which comprises the intermediate sheet 5 is bulky, there exists an advantage that a liquid permeate | transmits easily. This is particularly effective for permeation of highly viscous liquids. Due to the bulkiness, the intermediate sheet 5 has good liquid permeation, but the liquid absorption (retraction) is not so high. Therefore, in order to promote the drawing of the liquid from the top sheet 2 to the intermediate sheet 5, in the present embodiment, only the two of the top sheet 2 and the intermediate sheet 2 are partially combined by consolidation using embossing, Intermittently joined. A large number of joints 8 are formed on the top sheet 2 and the intermediate sheet 2 by this joining. Thereby, the density of the joint portion 8 in the top sheet 2 and the intermediate sheet 5 is higher than the peripheral region of the joint portion 8 in the top sheet 2 and the intermediate sheet 5. That is, in the top sheet 2 and the intermediate sheet 5, there is a difference in density between the joint portion 8 and its peripheral region. This density difference is reflected in the difference in capillary force. As a result, the excreted liquid is preferentially drawn into the intermediate sheet 5 from the position of the joint portion 8 due to the difference in capillary force. In addition, when the top sheet 2 and the intermediate sheet 5 are joined together, the characteristics of the intermediate sheet 5 having a soft and cushioned feeling are reduced. In order to prevent this, both are partially and intermittently joined as described above.
[0027]
Another advantage of joining the top sheet 2 and the intermediate sheet 5 by the joint portion 8 is that the occurrence of twisting while wearing the napkin is effectively prevented. As described above, since the intermediate sheet 5 is large and bulky, if the napkin 1 is worn for a long time, the intermediate sheet 5 is easily twisted due to the wearer's action. Generation | occurrence | production of twist can be prevented by joining 5 with the top sheet 2. Generation | occurrence | production of a twist can further be prevented by joining the intermediate sheet 5 also with the absorber 4, as mentioned later.
[0028]
From the viewpoint of transferring the liquid drawn into the intermediate sheet 5 to the absorber 4, it is preferable that the intermediate sheet 5 and the absorber 4 are in close contact with each other. In order to effectively perform this close contact, it is preferable that the intermediate sheet 5 and the absorber 4 are partially and intermittently joined by a predetermined joining means. As a joining means, it is convenient to use an adhesive such as a hot melt pressure-sensitive adhesive. In this case, the hot melt pressure-sensitive adhesive is preferably applied intermittently, for example, spirally so as not to hinder the liquid transfer from the intermediate sheet 5 to the absorber 4. Further, there is an advantage that the intermittent application can prevent the intermediate sheet 5 from becoming unnecessarily high in rigidity.
[0029]
  Since the intermediate sheet 5 is bulky and has a high liquid permeability and a large thickness, the masking effect on the color of menstrual blood is exhibited. Therefore, when excreted menstrual blood is absorbed by the absorber 4 through the intermediate sheet 5, the color of menstrual blood is reduced when the napkin 1 is viewed from the top sheet side, and the impression that the napkin 1 is soiled is used. It becomes difficult to give to the person. It also gives the user a sense of security that sufficient absorption capacity still remains. In particular, the L value (La) on the topsheet side before use of the napkin 1 and the L value (Lb) on the topsheet side after absorbing 2 g of defibrillated horse blood (manufactured by Japan Biotest Laboratories) Difference, that is, La-Lb is 55 or less,Preferably45 or lessWhen, No color difference on the surface, give a dirty impressionYes.The Lb value itself is preferably 35 or more, particularly 45 or more from the viewpoint that the napkin 1 looks white and clean. The L value is measured using a simple spectral color difference meter NF333 manufactured by Nippon Denshoku Industries Co., Ltd. The measurement is performed about 5 minutes after absorbing defibrinated horse blood.
[0030]
Next, components other than the intermediate sheet 5 in the napkin 1 will be described. As the top sheet 2, a material that has good touch and does not feel uncomfortable even when the napkin 1 is worn for a long time is preferably used. Examples of such materials include various nonwoven fabrics such as air-through nonwoven fabric, which is a bulky and soft nonwoven fabric, and apertured films. In particular, it is preferable to use an air-through nonwoven fabric that is soft and has a good cushion feeling. The air-through nonwoven fabric has a thickness of 0.2 to 1 mm, particularly 0.4 to 0.8 mm, and a basis weight of 15 to 40 g / m, in order to make the softness and cushion feeling more remarkable.², Especially 18-25 g / m²It is preferable that
[0031]
When a non-woven fabric is used as the top sheet 2, the non-woven fabric does not need to be perforated, but is preferably perforated as shown in FIGS. This facilitates permeation of the highly viscous liquid. When the nonwoven fabric is perforated, the perforated form is preferably a three-dimensional perforation as shown in FIG. Specifically, as shown in FIG. 3, the opening 10 is surrounded and formed by a nonwoven fabric that extends from the front surface 2 </ b> A of the top sheet 2 toward the back surface 2 </ b> B. And the inner wall of the opening 10 is formed by the continuous surface from the surface 2A. The opening 10 has an inverted conical shape whose diameter gradually decreases from the front surface 2A toward the back surface 2B. A space between adjacent openings is curved so as to have a top 11. In the top part 11, the back surface 2B of the top sheet protrudes toward the front surface 2A. A plurality of the top portions 11 are continuously connected to form a multi-row flange 12. A gap 13 is formed between the adjacent flanges 12, and the flanges 12 and the grooves 13 are alternately arranged so as not to have a flat portion. The flange portion 12 is curved in a convex shape and the groove portion 13 is curved in a concave shape, and the groove portion 13 has a large number of apertures 10 arranged at intervals. Specific examples of such a surface sheet are described in JP-A-8-246321 and JP-A-8-246322 related to the earlier application of the present applicant. Since the surface of the top sheet 2 has such a three-dimensional / curved surface, the surface becomes smooth, and even if the napkin 1 is worn for a long time, a sense of incongruity hardly occurs. In addition, since the contact area with the skin is small, stuffiness and blurring are unlikely to occur.
[0032]
As the absorber 4, a thin one is used from the viewpoint of reducing the thickness of the whole napkin. Moreover, what has sufficient absorption capacity although it is thin is preferable. As such an absorbent body, for example, an absorbent sheet in which particles of a superabsorbent polymer are sandwiched and fixed between two sheets of absorbent paper can be cited. Specific examples thereof are described in Japanese Patent Application Laid-Open No. 8-246395 related to the previous application of the present applicant.
[0033]
The thickness of the absorber 4 is preferably 0.2 to 2 mm, particularly preferably 0.5 to 1.7 mm, from the viewpoint that the thickness of the entire napkin can be reduced. For example, when the above-described absorbent sheet is used as the absorbent body 4, the thickness of the absorbent body 4 can be adjusted by folding the absorbent sheet into a C shape or overlapping a plurality of sheets. In particular, when the absorbent sheet is folded to form the absorbent body 4, the spring recoverability against compression occurs, so that the cushion feeling of the napkin 1 can be enhanced.
[0034]
Since the absorber 4 generally contains particles of a superabsorbent polymer, the rigidity tends to be high. Since the napkin 1 of the present embodiment is thin, if a highly rigid absorbent body is used, the rigidity is greatly reflected in the rigidity of the napkin 1. Therefore, the lateral Taber stiffness of the absorbent body 4 is lowered to 0.3 to 3.5 gf · cm, particularly about 0.5 to 2.5 gf · cm, so that the rigidity of the napkin 1 is not increased. preferable. As the absorber having such a Taber rigidity, the above-described absorbent sheet is preferably used. The Taber stiffness is measured according to a method described in a stiffness test method (JIS P 8125) using a paperboard Taber stiffness tester.
[0035]
As the back sheet 3, a thermoplastic resin sheet that is liquid impermeable can be used. This sheet is preferably moisture permeable. Thereby, even if the napkin 1 is worn for a long time, an increase in the humidity in the dress is suppressed, and it is possible to suppress swelling and blurring of the skin resulting therefrom. As a sheet | seat which has moisture permeability, the thing as described in Unexamined-Japanese-Patent No. 8-269220 which concerns on the previous application of this applicant, for example is mentioned.
[0036]
The napkin 1 of the present embodiment is preferably partially applied without bonding the back sheet 3 and the absorber 4 over the entire surface in order to improve the wearing feeling. Specifically, it is preferable to bond the two in an intermittent pattern such as a spiral shape, a linear shape, or a lattice shape. Furthermore, it is preferable that the patterns are formed at intervals in the width direction. The separation distance in the width direction is preferably 2 to 15 mm.
[0037]
The napkin 1 according to the present embodiment has a sufficient absorption capacity despite being thin, and is soft and has a high cushion feeling. Therefore, after a few days have passed since the start of menstruation, so-called light daily use is possible. As a napkin, it is particularly suitable for applications that are worn for a long time.
[0038]
The present invention is not limited to the embodiment. For example, although the said embodiment concerns the sanitary napkin as an example of an absorbent article, this invention is applicable similarly to other absorbent articles, such as a panty liner. In the present invention, a part of the absorbent article (for example, the central part, the rear part, both end parts, etc.) can also take a partially raised shape. The ratio of the raised portion in plan view is preferably 50% or less, particularly preferably 40% or less. With this level of swell, the effect of the swelled portion can be achieved without impairing the effects of the present invention. In this case, each thickness mentioned above is measured in a thin part. Further, when the thickness continuously changes, the thickness at the average portion of the maximum thickness and the minimum thickness is measured.
[0039]
【Example】
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. The napkins manufactured in the examples and comparative examples described below have a length of 170 mm, a maximum width of 75 mm, and a minimum width of 65 mm, and the absorbent body is formed by substantially rounding four corners of a square having a length of 140 mm and a width of 46 mm. It is. Constituent materials commonly used in Examples and Comparative Examples are as follows.
[0040]
[Top sheet]
25 g / m manufactured by air-through method using NBF (SH) fiber (2.2 dtex × 51 mm) manufactured by Daiwa Boseki Co., Ltd.²A non-woven fabric having a width of 55 mm and having a large number of apertures was used. The average diameter of the holes was 0.9 mm, and the area ratio of the holes was 8.7% (NEW QUBE ver.4.20K manufactured by NEXUS Co., Ltd. was used for measurement).
[Back sheet]
KTF37 manufactured by Mitsubishi Plastics Co., Ltd. was used.
[Fixing the top sheet and intermediate sheet]
The basis weight of 5g / m²Then, 5 pieces (spiral interval 0 mm) were spirally applied and fixed to a 15 mm wide region.
[Fixing of intermediate sheet and absorber]
The basis weight of 5g / m²Then, three pieces (spiral interval 10 mm, length 110 mm) were spirally applied and fixed in a region having a width of 15 mm.
[Slip prevention material]
In the center of the napkin, the area of 138 mm length and 50 mm width on the outer surface of the back sheet is coated with a coating length of 2 mm and a pitch of 2 mm, and the basis weight of hot melt (P-610G manufactured by Toyo Petrolite Co., Ltd.) 30 g / m²(The number of hot melts was 35).
[0041]
In the examples and comparative examples described below, it is described that embossing is present when only the top sheet and the intermediate sheet are subjected to hot embossing. This hot embossing embossing pattern is a staggered pin embossing (embossed portion φ1.5 mm, pitch 10 mm). Moreover, in the heat-fusible fiber to be used, the weight ratio of the fusion-bonding component and the high-melting-point component is 50:50 unless otherwise specified.
[0043]
    〔Example1]
Intermediate sheet: Two types of heat-fusible fibers were used. One was NBF (SP) fiber (7.7 dtex × 51 mm, melting point of fusion component: 128 ° C.) manufactured by Daiwabo Co., Ltd., and 50% by weight was used. The other was NBF (SH) fiber (4.4 dtex × 51 mm, melting point 135 ° C. of the fusion component) manufactured by Daiwabo Co., Ltd., and 50% by weight was used. After making these into a web with a card pile machine, a nonwoven fabric having a basis weight of 45 g / m 2 was produced by an air-through method and used as an intermediate sheet. The heat treatment temperature for forming the nonwoven fabric was 150 ° C.
·Absorber:An absorbent sheet was produced according to the method for producing an absorbent sheet described in Production Example 1 of JP-A-8-229070. The fiber web used has a dry basis weight of 25 g / m. ² The amount used of the absorbent polymer (CAW-4 manufactured by Nippon Shokubai Co., Ltd.) is 20 g / m. ² The basis weight of the pre-made absorbent paper is 25 g / m ² Met.
・ Hot melt for fixing: In order to fix the back sheet and the absorbent body, Esdyne manufactured by Sekis Dyne Co., Ltd. has a basis weight of 10 g / m.²Then, three pieces (spiral interval 10 mm) were applied in a spiral shape to a region having a width of 15 mm.
・ Embossed.
[0046]
    〔Example2]
Intermediate sheet: NBF (SP) fiber (4.4 dtex x 51 mm) manufactured by Daiwa Boseki Co., Ltd. as a raw material, which was web-formed with a card pile machine and then weighed 60 g / m by air-through method²A non-woven fabric was produced and used as an intermediate sheet. The heat treatment temperature for making the nonwoven fabric was 142 ° C., and the melting point of the fiber fusion component was 135 ° C.
Absorbent: An absorbent sheet was produced according to the method for producing an absorbent sheet described in Production Example 1 of JP-A-8-229070. The used fiber web is made of Wafer User's Pulp NB-420 and has a dry basis weight of 20 g / m.²The amount of the absorbent polymer (CAW-4 manufactured by Nippon Shokubai Co., Ltd.) used is 18 g / m.²The preliminarily made absorbent paper is a basis weight of 20 g / m using Wafer User's Pulp NB-420.²It was a thing. Two sheets of this absorbent sheet were stacked to form an absorbent body.
・ Fixing hot melt: Examples1The same one was used.
・ Embossed.
[0047]
[Comparative Example 1]
・ Intermediate sheet: NBF (SP) fiber (4.4 dtex x 51 mm) manufactured by Daiwa Boseki Co., Ltd. as a raw material.²A non-woven fabric was produced and used as an intermediate sheet. The heat treatment temperature for forming the nonwoven fabric was 160 ° C., and the melting point of the fiber fusion component was 135 ° C.
Absorber: The same one as in Example 1 was used.
Fixing hot melt: The same hot melt as in Example 1 was used.
[0048]
[Comparative Example 2]
Intermediate sheet: NBF (SH) fiber (3.3 dtex × 51 mm) manufactured by Daiwa Boseki Co., Ltd. as a raw material. After forming a web by the airlaid method, the basis weight is 30 g / m by the air-through method.²A non-woven fabric was produced and used as an intermediate sheet. The heat treatment temperature for forming the nonwoven fabric was 150 ° C., and the melting point of the fiber fusion component was 128 ° C.
Absorber: The same one as in Example 5 was used.
Fixing hot melt: The same hot melt as in Example 1 was used.
[0049]
[Comparative Example 3]
-Top sheet: Cot Ace CO35S / A01 manufactured by Unitika Ltd. was used.
Intermediate sheet: The same sheet as in Example 4 was used.
Absorber: The same one as in Example 1 was used.
Fixing hot melt: The same hot melt as in Example 1 was used.
[0050]
[Comparative Example 4]
・ Intermediate sheet: NBF (SH) fiber (2.2 dtex × 51 mm) manufactured by Daiwa Boseki Co., Ltd. as a raw material.²A non-woven fabric was produced and used as an intermediate sheet. The heat treatment temperature for forming the nonwoven fabric was 160 ° C., and the melting point of the fiber fusion component was 128 ° C.
Absorbent: Basis weight 180 g / m made of Wafer User's Pulp NB-420²The fiber assembly was used as an absorbent.
Fixing hot melt: The same hot melt as in Example 1 was used.
[0051]
[Performance evaluation]
About the napkin obtained by the Example and the comparative example, the quality of mounting | wearing feeling and the twist prevention property were evaluated with the following method. The results are shown in Table 1 below.
[0052]
[Evaluation of quality of wearing and prevention of twisting]
Each of the napkins of Examples and Comparative Examples was used by 10 women, and was evaluated in five stages: 5: good, 4: good, 3: normal, 2: not good, 1: not good. The evaluation values of 10 persons were averaged, and the quality of the wearing feeling was evaluated by the obtained numerical values. When the numerical value is 3.5 or more, it is determined that a desired effect is obtained.
Anti-spinning is achieved by injecting 2 g of equine defibrinated blood (manufactured by Japan Biotest Laboratories Co., Ltd.) into a napkin and attaching it to a female waist model whose legs move back and forth. Were observed to evaluate the anti-rotation property. Three napkins were used for each, and the evaluation was made in three stages: ○: little twist, Δ: slightly twisted, and × twisted. If the evaluation is ◯, it is determined that the desired effect has been obtained.
[0053]
[Table 1]

[0054]
As is apparent from the results shown in Table 1, it can be seen that the napkins of the examples have a good wearing feeling and the occurrence of twisting is prevented. On the other hand, it can be seen that the napkin of the comparative example does not have a good feeling of wearing and is liable to be twisted.
[0055]
【The invention's effect】
The absorbent article of the present invention has sufficient absorbency despite being thin, soft and has a good cushion feeling, a comfortable wearing feeling, and little twist. Therefore, the absorbent article of the present invention is suitable for long-time wearing.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a sanitary napkin as an embodiment of an absorbent article of the present invention.
FIG. 2 is a cross-sectional view taken along the line II-II in FIG.
FIG. 3 is an enlarged schematic view showing a main part of a top sheet.
[Explanation of symbols]
1 Sanitary napkin (absorbent article)
2 Top sheet
3 Back sheet
4 Absorber
5 Intermediate sheet

Claims (5)

In an absorbent article comprising a liquid-permeable top sheet, a liquid-impermeable back sheet, and a liquid-retaining absorbent disposed between both sheets,
A liquid-permeable intermediate sheet is disposed between the top sheet and the absorber, and the intermediate sheet contains 25 to 100% by weight of fibers having a fineness of 3.3 to 11 dtex, and two or more kinds of heat melts. Among the fusing components that comprise adhesive fibers and constitute those heat-fusible fibers, the melting point mp _{max of the} thermal fusing component having the highest melting point and the melting point of the thermal fusing component having the lowest melting point difference mp _max -mp _min with mp _min is a nonwoven fabric is 5 ° C. or higher, further intermediate sheet itself having a thickness with the thickness of the intermediate sheet is 30 to 60% of the thickness of the absorbent article 0. 8-2mm,
The absorbent article has a thickness of 1.5 to 4 mm and a thickness change rate of 20% or more, and absorbs the L value (La) on the topsheet side before use and 2 g of defibrinated horse blood. difference La-Lb 55 der following the topsheet side of the L value (Lb) of the after is,
Said topsheet, said intermediate sheet, the absorber and out of the backsheet, the absorbent article the thickness of the intermediate sheet that has most increased. The absorbent article according to claim 1, wherein the sum of the thicknesses of the top sheet and the intermediate sheet is 45 to 90% of the thickness of the absorbent article, and the absorber has a thickness of 0.2 to 2 mm . The absorbent article according to claim 1 or 2, wherein the repulsive force at 40% compression is 5 to 20 cN / cm ² and the bending rigidity is 10 cN · cm / cm or less . The top sheet is formed of a non-woven fabric, and only two of the top sheet and the intermediate sheet have a large number of joints formed by being partially joined by embossing. An absorbent article according to any one of the above . The said intermediate sheet contains a core-sheath-type composite fiber, and the weight ratio of the core component of a core-sheath type composite fiber and a sheath component consists of a nonwoven fabric whose core: sheath = 55: 45-80: 20. An absorbent article according to any one of the above .

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