JP2010063814A - Body fluid absorptive article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a body fluid absorptive article having a groove formed by compression. <P>SOLUTION: The body fluid absorptive article 1 has the groove 11 compressed and formed in a direction from a surface sheet 2 to a back surface sheet 3. At the bottom part of the groove 11, a low compression part 18 and a high compression part 19 are alternately formed, and a core material 4 is thicker in the low compression part 18 than in the high compression part 19. The low compression part 18 and the high compression part 19 are connected by inclined surfaces 22 and 23 having a smooth downward gradient, and the density of the core material 4 is gradually increased from the peak part 21 of the low compression part 18 to the high compression part 19. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a bodily fluid absorbent article suitable for use as a sanitary napkin or pad for absorbing vaginal discharge.

It is well known that a body fluid absorbent article such as a sanitary napkin is formed with compressed grooves extending in the longitudinal direction on both sides in the lateral direction. It is also well known that at the bottom of the squeezing groove, a part where the bodily fluid-absorbing core material is squeezed at high density and a part where the squeezed squeeze is arranged alternately are arranged in the longitudinal direction. is there. For example, a sanitary napkin disclosed in Japanese Patent Laid-Open No. 9-108262 (Patent Document 1) has a pair of grooves extending in the length direction of the napkin, and the bottom of the grooves crosses the bottom. The extended high pressure parts and the low pressure parts are alternately formed in the longitudinal direction of the napkin. Japanese Patent Laid-Open No. 2002-119540 (Patent Document 2) discloses a pressurization for forming a groove in a sanitary napkin in which high-pressure parts and low-pressure parts are alternately arranged in the longitudinal direction of the sanitary napkin. A compressed groove forming apparatus composed of a roll and an anvil roll is disclosed.
JP-A-9-108262 JP 2002-119540 A

  The aspect which the high pressing part and low pressing part formed in the groove | channel of patent document 1 and the pressing groove of patent document 2 connect in the vertical direction of a sanitary napkin forms the surface of a horizontal high pressing part. The thickness of the core material under the bottom of the compressed groove, and the bottom of the compressed groove intersects with a substantially vertical wall extending across the groove in the low pressure portion Changes abruptly at the site moving from the low pressure part to the high pressure part. In the pressing process of the core material in which such a part is formed, the elongation ratio of the liquid-permeable sheet covering the core material is locally increased, the liquid-permeable sheet is torn, and the compressed groove has a poor appearance. Or the core material may spill out from the torn portion of the liquid-permeable sheet, which may make the sanitary napkin uncomfortable.

  This invention makes it a subject to improve the body fluid absorbent article of the prior art which has such a problem.

  In order to solve the above-described problems, the present invention is directed to a body fluid having a longitudinal direction, a lateral direction, and a thickness direction orthogonal to each other between a liquid-permeable top sheet and a liquid-impervious back sheet. An absorbent core material is interposed, and on both sides in the lateral direction, the top sheet and the core material are squeezed in a direction from the top sheet to the back sheet to form a groove extending in the vertical direction, At the bottom of the groove, there is a high-pressure squeezed part in which the thickness of the core material is the thinnest among the bottom parts, and a low-pressure squeezed part in which the thickness of the core material is thicker than the high-pressure squeezed part. It is a bodily fluid absorbent article formed alternately in the longitudinal direction.

  In such a bodily fluid absorbent article, the present invention is characterized in that, at the bottom of the groove, the low-pressure portion has a top portion above the thickness direction, and the top portion and the low-pressure portion in the longitudinal direction. The high-pressure parts adjacent to each other are connected by an inclined surface having a smooth downward slope, and the density of the core material is gradually increased from the top part toward the high-pressure parts.

  In one preferred embodiment of the present invention, when the body fluid absorbent article is placed on a horizontal plane, the angle between the inclined surface and the horizontal plane is in the range of 20 to 80 °.

  In one of preferred embodiments of the present invention, the high pressing portion has the vertical dimension in the range of 1 to 5 mm, the horizontal dimension in the range of 2 to 5 mm, and the low pressing portion. The vertical dimension is in the range of 2-8 mm and the horizontal dimension is in the range of 2-5 mm.

  In another preferred embodiment of the present invention, tissue paper containing pulverized pulp is interposed between the high pressure portion and the back sheet, and the tissue paper is in close contact with the high pressure portion.

  In the bodily fluid absorbent article according to the present invention, the low-pressure squeezed portions in the groove portions formed on both sides in the lateral direction have a top portion in the thickness direction, and the top portion and the high-pressure squeezed portion adjacent to the low-pressure squeezed portion are smooth. It is connected by an inclined surface with a downward slope. Therefore, when squeezing the surface sheet and core material of the body fluid absorbent article to form the groove, the degree of compression is gradually increased from the portion that should be the top of the low pressure portion toward the portion that should be the high pressure portion. Since it can raise, the generation | occurrence | production of the problem that a surface sheet is extended | stretched locally with a high expansion | extension rate and torn can be suppressed.

  Taking a sanitary napkin as an example of the body fluid absorbent article, the details of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a partially broken plan view of a sanitary napkin 1, and a vertical direction, a horizontal direction, and a thickness direction (see FIG. 3) of the napkin 1 that are orthogonal to each other are indicated by A, B, and C. The napkin 1 has a liquid-permeable top sheet 2, a liquid-impervious back sheet 3, and a body fluid-absorbing core material 4. The core material 4 has high water-absorbing fibers such as pulverized pulp or water-absorbing fibers. It includes an aggregate 6 of a water-absorbing material formed by a mixture with water-absorbing polymer particles and the like, and two tissue papers 7a and 7b sandwiching this. The top sheet 2 and the back sheet 3 extend from the periphery of the core material 4 and overlap each other, and the overlapping portions are pressurized under heating and joined to each other to form the periphery seal portion 8. The vertical pressing grooves 11 extending in the vertical direction A are formed on both sides of the napkin 1 in the horizontal direction B, and the horizontal pressing grooves 12 extending in the horizontal direction B are formed on both ends of the vertical direction A.

  FIG. 2 is an enlarged view of a portion II of the vertical pressing groove 11 in FIG. The vertical pressing groove 11 has a pair of side wall portions 17 a and 17 b facing each other with the bottom portion 16, and low pressure pressing portions 18 and high pressure pressing portions 19 are alternately arranged in the vertical direction A on the bottom portion 16. The low pressing portion 18 and the high pressing portion 19 also extend in the lateral direction B so as to intersect the side wall portions 17a and 17b.

  3 is a cross-sectional view taken along line III-III in FIG. In the high-pressure squeezing part 19 among the low-pressure squeezing parts 18 and the high-pressure squeezing parts 19 that are alternately arranged in the vertical direction A in the vertical squeezing groove 11, the top sheet 2 and the core material 4 are strongly squeezed locally in the thickness direction. The core material 4 of the high pressing portion 19 has a higher density than the core material 4 around the high pressing portion 19. The core material 4 may also be firmly attached to the tissue papers 7a and 7b. The high-pressure portion 19 has a substantially uniform thickness and is formed so as to spread substantially horizontally in the vertical direction A and the horizontal direction B. The low-pressure squeezed part 18 has the top sheet 2 and the core material 4 slightly squeezed compared to the high-pressure squeezed part 19, has a top part 21 above the thickness direction C, and both sides of the top part 21 in the longitudinal direction A. Have inclined portions 20a and 20b. The inclined portions 20a and 20b have inclined surfaces 22 and 23 formed by the surface sheet 2, and the inclined surfaces 22 and 23 of the high pressing portion 19 adjacent to the low pressing portion 18 in the longitudinal direction A from the top portion 21. Each has a smooth downward slope, more preferably a smooth and substantially uniform downward slope. In the low-pressure squeezed part 18, the core material 4 is squeezed from the top part 21 toward the high-pressure squeezed part 19, in other words, the density gradually increases as it goes down the inclined surfaces 22 and 23. The tissue paper 7a may be bonded to the top sheet 2 or not bonded to the top sheet 2 in the portion covering the assembly 6 except for the vertical pressing groove 11 and the horizontal pressing groove 12. The tissue paper 7b may or may not be bonded to the back sheet 3 at the portion covering the assembly 6. For joining the tissue paper 7 a and the top sheet 2 and joining the tissue paper 7 b and the back sheet 3, a hot melt adhesive applied intermittently to the top sheet 2 or the back sheet 3 can be used.

  The vertical pressing groove 11 can be obtained by pressing a required portion of the sanitary napkin with a mold having a convex portion for forming the low-pressure pressing portion 18 and a concave portion for forming the high-pressure pressing portion 19. When squeezing sanitary napkins, molds and sanitary napkins are heated to an appropriate temperature, or sanitary napkins are appropriately moisturized, and surface sheets, pulverized pulp, superabsorbent polymer particles, etc. It is possible to facilitate deformation and elongation of the constituent material. In the vertical squeezing groove 11, the dimension in the vertical direction A of the low-pressure squeezed portion 18 is p, and preferably in the range of 2 to 8 mm. The dimension of the high pressure portion 19 in the longitudinal direction A is q, the dimension in the lateral direction B is r, preferably the dimension q is in the range of 1 to 5 mm, and the dimension r is in the range of 2 to 5 mm. If the dimension q or the dimension r is larger than 5 mm, the area occupied by the high-pressure squeezed part 19 at the side part of the napkin 1 becomes large, and the tendency to make the napkin 1 poor in flexibility becomes strong. In addition, when the dimension q is smaller than 1 mm or when the dimension r is smaller than 2 mm, the pressing portion of the mold used to form the high pressing portion 19 has a sharp tip. In the process of squeezing, the possibility of breaking the top sheet 2 is increased.

  In the vertical pressing groove 11, the inclination angle formed by the inclined surfaces 22 and 23 of the low-pressure expression portion 18 and the horizontal line H is α, and the preferable inclination angle α of the low-pressure expression portion 18 is in the range of 20 to 80 degrees. .

  In the napkin 1 thus formed, when the top sheet 2 and the core material 4 are squeezed from the top sheet 2 toward the back sheet 3 to form the vertical squeezing grooves 11, the top sheet 2 is low-pressure squeezed. Since the elongation ratio is gradually increased along the inclined surfaces 22 and 23 from the top portion 21 of the portion 18 to the high pressing portion 19, the topsheet 2 is broken by being locally elongated at a high elongation ratio. The occurrence of the problem can be avoided. When this napkin 1 is worn and menstrual blood diffuses from the central portion in the lateral direction B of the napkin 1 toward the vertical pressing groove 11, menstrual blood that has entered the low pressing portion 18 is transferred from the top portion 21 to the high pressing portion. In the inclined portions 20a and 20b, the density of which gradually increases toward 19 is guided toward the high pressing portion 19. The tissue paper 7 b is in close contact with the aggregate 6 of the water-absorbing material in the high-pressure squeezed portion 19, and the tissue paper 7 b is superior in ability to diffuse body fluid than the aggregate 6. Therefore, since the menstrual blood guided to the high-pressure squeezed part 19 has a strong tendency to diffuse between the assembly 6 and the back sheet 3, the surface of the high-pressure squeezed part 19 by the menstrual blood that has entered from the low-pressure squeezed part 18. It is less likely that the sheet 2 is soiled. Such a napkin 1 is less likely to stain the skin with menstrual blood that has entered the vertical squeezing groove 11 depending on the amount of menstrual blood.

  FIG. 4 is a partially cutaway perspective view of the napkin 1 and shows the vertical pressing groove 11 and its periphery. In the vertical pressing groove 11, the inclination angle of the side wall 17a with respect to the horizontal line H is β, the inclination angle of the side wall 17b with respect to the horizontal line H is γ, and the preferable inclination angles β and γ in the vertical pressing groove 11 are 30 degrees or more, 90 It is in the range of less than degrees. When the inclination angle β is in such a range, even if the pressure in the thickness direction C acts on the napkin 1, the vertical pressing groove 11 is less likely to be blocked by the surrounding water-absorbing material. When the inclination angles β and γ are less than 30 degrees, the vertical pressing groove 11 is likely to have a problem that the width is too wide or the depth is too shallow. In addition, when the inclination angles β and γ are 90 degrees or more, when the vertical pressing groove 11 is formed in the napkin 1, the vertical pressing groove 11 is affected by the fact that the topsheet 2 is easily torn and the body pressure acting on the napkin 1. May easily become closed.

  In the illustrated example, each of the low-pressure squeezed portion 18 and the high-pressure squeezed portion 19 in the vertical squeezing groove 11 extends so as to be parallel to the lateral direction B. And the high pressure portion 19 may be inclined with respect to the lateral direction B, in other words, may extend so as to intersect the longitudinal direction A.

  Moreover, the horizontal pressing groove 12 formed in the napkin 1 in FIG. 1 is such that the low pressure pressing portion 18 and the high pressing portion 19 illustrated in FIG. 2 extend in the vertical direction A, and alternately in the horizontal direction B. Except for being aligned, it can be said that it is formed in the same manner as the vertical pressing groove 11. However, this invention can also be implemented with the body fluid absorbent article in which the lateral pressing groove 12 is not formed.

The partially broken top view of the sanitary napkin. The elements on larger scale of FIG. III-III sectional view taken on the line of FIG. The partial perspective view of a sanitary napkin.

Explanation of symbols

1 Body fluid absorbent article (Sanitary napkin)
2 surface sheet 3 back sheet 4 core material 7b tissue paper 11 pressing groove (longitudinal pressing groove)
18 Low pressure part 19 High pressure part 20a, 20b Inclination part 21 Top part 22 Inclination surface 23 Inclination surface A Longitudinal direction B Lateral direction C Thickness direction

Claims (4)

It has a longitudinal direction, a transverse direction and a thickness direction perpendicular to each other, and a body fluid-absorbing core material is interposed between the liquid-permeable top sheet and the liquid-impervious back sheet, The top sheet and the core material are squeezed in the direction from the top sheet to the back sheet to form a groove extending in the vertical direction, and the bottom portion of the groove has a thickness of the core material among the bottom portions. The squeezed high-pressure portion and the low-pressure squeezed portion in which the core material is thicker than the high-pressure portion are alternately disposed in the longitudinal direction. And
In the bottom portion of the groove, the low-pressure portion has a top portion in the thickness direction, and the top portion and the high-pressure portion adjacent to the low-pressure portion in the longitudinal direction have a smooth downward slope. The bodily fluid-absorbent article is characterized in that the density of the core is gradually increased from the top toward the high-pressure portion.   The humor absorbent article according to claim 1, wherein when the humor absorbent article is placed on a horizontal plane, an angle between the inclined surface and the horizontal plane is in a range of 20 to 80 °.   The high pressing portion has a longitudinal dimension of 1 to 5 mm and the lateral dimension of 2 to 5 mm, and the low pressing portion has a longitudinal dimension of 2 to 8 mm. The body fluid absorbent article according to claim 1 or 2, wherein the lateral dimension is in a range of 2 to 5 mm.   The body fluid absorptivity according to any one of claims 1 to 3, wherein tissue paper containing pulverized pulp is interposed between the high-pressure portion and the back sheet, and the tissue paper is in close contact with the high-pressure portion. Goods.

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