JP6692954B2 - Absorbent article - Google Patents

Description

  The present invention relates to absorbent articles such as sanitary napkins and diapers.

Nonwoven fabrics are often used for absorbent articles such as sanitary napkins from the viewpoint of touch and the like. Various proposals have been made for this non-woven fabric.
For example, Patent Document 1 describes a non-woven fabric including free fibers spanning the raised fibers from the viewpoint of improving the touch of the non-woven fabric having the raised fibers.
Patent Document 2 describes an absorbent article including a barrier layer including a spunbonded nonwoven web and a meltblown nonwoven web. Regarding the barrier layer, the number average fiber diameter of the fibers of each nonwoven web and the total weight percentage of the meltblown nonwoven web are set within a specific range from the viewpoint of imparting not only barrier properties but also high flexibility and flexibility for sensitive skin. I try to keep it down.

JP, 2016-65335, A Special table 2011-529749 gazette

Even in the conventional non-woven fabrics described in Patent Documents 1 and 2 and the melt-blown non-woven fabrics which are generally considered to have a small inter-fiber distance, fine through-holes between the fibers are generated. When such a non-woven fabric is used as the leak-proof layer of the absorbent article, liquid leakage can be prevented depending on the size of the through-hole with a certain amount of liquid. However, there is a limit to the liquid volume.
On the other hand, it is conceivable to reduce the diameter of the fibers of the non-woven fabric or increase the basis weight of the non-woven fabric to fill the joints between the fibers and close the through holes to some extent. However, this method increases the amount of fibers, may increase the hardness of the non-woven fabric, and may impair the texture, and cannot be a real solution for a leak-proof layer of an absorbent article that comes into contact with the skin.
Further, in the calendering process used in the conventional method for producing a nonwoven fabric, the eyes between the fibers can be closed to some extent when the fibers are compressed. However, it is difficult to completely close the through holes that lead to liquid leakage in the region where there are no fibers. By intentionally increasing the thermocompression bonding by calendering (increasing the pressure bonding force and increasing the pressure bonding area), the nonwoven fabric is hardened due to the crushing of the fibers, and the softness is lost accordingly.

  In view of the above points, the present invention relates to an absorbent article including a leak-proof layer made of a non-woven fabric having enhanced liquid leak prevention properties without impairing softness.

The present invention is an absorbent article having a surface layer, a leak preventive layer, and an absorbent layer arranged between the surface layer and the leak preventive layer, wherein the leak preventive layer is directly laminated on the absorbent layer. The leakproof layer has a meltblown layer and a protective layer of the meltblown layer, and has an embossed portion where both layers are joined and a non-embossed portion other than the embossed portion, and the leakproof layer is non- A fiber having a non-opening region in the embossed portion, and the non-opening region includes a region in which a rectangular area having a diagonal length of 10 μm has an area of 25 μm ² or more when the leak-proof layer is viewed in a plan view. Provided is an absorbent article, wherein the interspace is a region that does not have a through hole penetrating in the thickness direction, and the non-opening region is arranged in a region where the leak preventive layer overlaps with the absorbent layer.
Further, the present invention is an absorbent article having a surface layer, a leak preventive layer, and an absorbent layer arranged between the surface layer and the leak preventive layer, wherein the leak preventive layer directly contacts the absorbent layer. Laminated, the leak-proof layer has a melt-blown layer and a protective layer of the melt-blown layer, the protective layer is arranged on the non-absorbing layer side of the melt-blown layer, the leak-proof layer, the protective layer. The fibers of the meltblown layer that enter the layer have a raised area of 2.5 fibers / mm or more, and the average fiber diameter of the fibers of the meltblown layer is 2.5 μm or less. There is provided an absorbent article, wherein a leaky layer is arranged in a region overlapping with the absorbent layer.

  The absorbent article of the present invention includes a leak-proof layer made of a non-woven fabric having enhanced liquid leak prevention properties without impairing softness.

It is sectional drawing which shows one Embodiment of the absorbent article of this invention. It is explanatory drawing which shows typically the method of confirming "the area | region where the area of the rectangle which consists of diagonal length 10 micrometers is 25 micrometers ² or more" regarding the nonwoven fabric which comprises the leak-proof layer of the absorbent article of this invention. It is a partially expanded sectional view which shows typically the preferable form of the nonwoven fabric which comprises the leak-proof layer of the absorbent article of this invention. It is a partially expanded sectional view which shows typically another preferable form of the nonwoven fabric which comprises the leak-proof layer of the absorbent article of this invention. It is a drawing substitute photograph which imaged the cross section of the nonwoven fabric corresponded to FIG. It is a drawing substitute photograph imaged from the surface by the side of the non-absorption layer of the nonwoven fabric shown in FIG.

  The absorbent article of the present invention will be described below based on its preferred embodiments with reference to the drawings. The absorbent article of the present invention can be applied to various things that absorb and retain excreted liquid, and examples thereof include diapers, sanitary napkins, panty liners, incontinence pads, urine absorbing pads, and the like.

  In the present invention, unless otherwise specified, the side contacting the human body is referred to as the skin side, the skin contact surface side or the front surface side, and the opposite side is the non-skin surface side, the non-skin contact surface side or the back surface side. That. In particular, the skin contact surface side and the non-skin contact surface side of the leak preventive layer may be referred to as the absorption layer side and the non-absorption layer side. Further, the normal direction of the front surface or the back surface of the absorbent article is called the thickness direction, and the amount thereof is called the thickness.

  FIG. 1 shows a cross section of the absorbent article 10 of the present embodiment. The absorbent article 10 includes a liquid-permeable surface layer 1 arranged on the skin contact surface side, a leak preventive layer 2 arranged on the non-skin contact surface side, and between the surface layer 1 and the leak preventive layer 2. It has a liquid-retaining absorption layer 3 arranged in. The absorbent layer 3 is a layer of a hydrophilic material arranged closer to the non-skin contacting surface side than the surface layer 1, and is not only an aggregate (absorbent core) of liquid absorbent material such as pulp or water-absorbing polymer, A cover sheet (also referred to as a core wrap sheet) that covers the aggregate of the liquid absorbent may be included. Examples of the covering sheet include liquid-permeable fiber sheets such as thin paper (tissue paper) and non-woven fabric.

  The leakproof layer 2 is directly laminated on the absorption layer 3. That is, the leak-proof layer 2 and the absorption layer 3 are laminated without any other layer except for the agent (adhesive or the like) used for joining the two. In the absorbent article 10 of the present embodiment, the leak preventive layer 2 forms the layer of the absorbent article 10 closest to the non-skin contact surface side. In the absorbent article of the present invention, the leak preventive layer does not necessarily have to be the layer closest to the non-skin contact surface side. For example, when the absorbent article of the present invention is a sanitary napkin or the like, an adhesive for fixing to the clothes on the non-skin contact surface side of the leak-proof layer, a release paper for covering the adhesive until it is used, etc. May be arranged. Further, it is preferable that the absorbent article 10 of the present embodiment does not have a film on the non-skin contact surface side of the absorbent layer 3. The leak-proof layer 2 preferably has a surface 21 on the absorbent layer side 2A that abuts the absorbent layer 3 and a surface 22 on the non-absorbent layer side 2B. The surface 22 on the non-absorption layer side 2B of the leakproof layer 2 preferably constitutes the outer surface of the absorbent article 10.

  The leakproof layer 2 has a fiber layer 4 such as a nonwoven fabric as a constituent element. Specifically, as shown in FIG. 3, the leakproof layer 2 includes a fiber layer 4 having a meltblown layer 41 and a protective layer 42 for the meltblown layer 41. The protective layer 42 is preferably disposed on at least the non-absorption layer side of the meltblown layer 41. The protective layer 42 is a layer that reinforces the strength and the like of the meltblown layer 41. The leakproof layer 2 preferably has an embossed portion (not shown) to which the meltblown layer 41 and the protective layer 42 are joined and a non-embossed portion (not shown) other than the embossed portion. Here, the embossed portion is an area where the constituent fibers of the fiber layer 4 are consolidated by hot embossing. The embossed portion formed on the fiber layer 4 by this consolidation has a reduced thickness as compared to other portions of the fiber layer 4. The embossed portion has, for example, a circular shape, a rectangular shape, or the like, and can be formed in a dotted shape over the entire area of the fiber layer 4. Alternatively, a plurality of linear or curved embossed portions can be formed. The plurality of linear or curved embossed portions may be formed so as to intersect with each other.

  The leakproof layer 2 preferably has synthetic fibers as constituent fibers and is water repellent. Thereby, the leak-proof layer 2 has a function of not leaking the excreted liquid that has permeated from the surface layer 1 and is absorbed by the absorbent layer 3 to the outside of the absorbent article 10. Therefore, it is preferable that the leakproof layer 2 having the fiber layer 4 as a constituent element has the following fiber structure in a region overlapping with the absorption layer 3.

That is, it is preferable that the leakproof layer 2 has a non-opening region in the non-embossed portion in a region overlapping the absorption layer 3. The non-perforated region is a “through hole in which an interfiber space including a region having a rectangular area having a diagonal length of 10 μm and having an area of 25 μm ² or more in a plan view penetrates in the thickness direction” (hereinafter, “through hole”). It is a region that does not have. The size of the “region in which the area of the rectangle having a diagonal length of 10 μm and the area of 25 μm ² or more” is a size in which the exudation of water from the leak preventive layer may occur in the following conditions. That is, the excreted liquid in the absorbent article reaches the leak preventive layer from the surface layer, and the water (liquid such as excreted liquid absorbed by the absorbent article) is subjected to a seat pressure. The through-hole is a hole having a predetermined size and penetrating in the thickness direction as defined above, and the “non-open area” having no through-hole is the surface of the leak-proof layer 2 on the absorbent layer side 2A. 21 or the surface 22 on the non-absorption layer side 2B.

The “plan view” here is to observe from above the sheet surface of the leak preventive layer 2 (the surface 21 on the absorbent layer side 2A or the surface 22 on the non-absorbent layer side 2B). In addition, the "holes penetrating in the thickness direction" referred to here are "interfiber spaces where the area of a rectangle having a diagonal length of 10 µm is 25 µm ² or more in plan view" while maintaining the area. It is a hole penetrating in the thickness direction of the leak layer 2.
Furthermore, the requirements for the length and area of the diagonal line defined for the "through hole" here are, in relation to the excreted liquid absorbed in the absorbent article, the size that exudes when water is subjected to a seat pressure. It means that.

(Measuring method of through holes)
The presence or absence of the through hole can be measured by the following method.
That is, a scanning electron microscope (SEM) (for example, JCM-6000PLUS manufactured by JEOL Ltd.) is used for the sheet surface (the surface 21 of the absorption layer side 2A or the surface 22 of the non-absorption layer side 2B) of the leakproof layer 2. (Brand name), and the same applies to other parts of the present specification.), And observation is performed at an observation magnification of 3000 times, from the front of the observation screen (or the imaging screen) to the back (of the leak preventive layer 2). When viewed in the thickness direction), the inter-fiber space that penetrates without being blocked by the fibers is specified. It is examined whether a rectangle (including a square) in which two straight lines of 10 μm scale intersect at the midpoint can be drawn with respect to this interfiber space. Then, when the area of the rectangle is 25 μm ² or more, it is determined that the through hole exists.
The area of the rectangle is calculated based on the following formula [1]. In the above rectangle, the smaller one of the angles at which the straight line at the midpoint intersects is set as the intersection angle θ (0 ° ≦ θ ≦ 90 °), and the intersection angle θ is measured. The area of a rectangle having a crossing angle θ of 30 ° or more on a diagonal line of 10 μm is 25 μm ² or more.
Area of rectangle = (1/2) x (diagonal length: 10 µm) ² x sin θ [1]
For the above measurement, when taking out the leak preventive layer from the commercially available absorbent article, the cold spray is separated from the outermost side by 10 cm and is sprayed for about 5 seconds to solidify the hot melt which adheres between the respective materials to prevent the leak. Carefully peel off the layers. This extracting means is also applied to other measuring methods in this specification.

  The method of measuring the through hole can be performed, for example, as shown in FIG. That is, when the leak preventive layer 2 is observed from the surface 21 on the absorbent layer side 2A or the surface 22 on the non-absorbent layer side 2B, a space 49 surrounded by the fibers 48 and not blocked by other fibers in the thickness direction. Specify. Next, the penetration defined above depends on whether or not a rectangle E having two straight lines (intersecting at a midpoint on a 10 μm scale and intersecting angle θ = 30 ° or more and 90 ° or less) E1 and E1 as diagonal lines can be drawn. Determine if holes are present. When the rectangle E can be drawn, it is determined that the leakproof layer to be observed has the through hole, and when the rectangle E cannot be drawn, it is determined that the leakproof layer to be observed does not have the through hole.

Examples of the case where the leak preventive layer 2 does not have the through holes defined above include the following modes. That is, even if there is an interfiber space that meets the above-mentioned diagonal line and area requirements on the front surface when viewed in a plan view, there is a fiber that blocks it, and the "hole" remains the same size as above. Then, in the case where it does not penetrate in the thickness direction, the leakproof layer 2 does not have the through hole. In addition, even when the inter-fiber space seen on the near side when observing the through-hole in a plan view is small enough not to draw a diagonal rectangle having a length of 10 μm, the leakproof layer 2 has the above-mentioned through-hole. I don't. Similarly, even when there is a small hole having an area of 25 μm ² or more (that is, less than 25 μm ² ) in a rectangle drawn so that two straight lines on the 10 μm scale intersect at a midpoint, the leakproof layer 2 penetrates It has no holes.

Examples of the method for allowing the leak-proof layer 2 to have the non-opened area having no through-hole defined above include various methods such as a method of increasing the number of fibers by increasing the basis weight.
Among them, the leakproof layer 2 preferably has the structure shown below from the viewpoint of maintaining softness without excessively increasing the amount of fibers and enhancing the liquid leakproofness.

  That is, the leak-proof layer 2 has a structure in which the melt-blown layer 41 and the protective layer 42 are laminated as described above. In the leak-proof layer 2, the fibers of the melt-blown layer 41 that have entered the protective layer 42 in the region overlapping the absorption layer 3. It is preferable to have the raised area 6 of 2.5 fibers / mm or more (see a partially enlarged view in a circle indicated by a symbol P in FIG. 3).

  The “raised region 6” here means the fiber structure inside the leak-proof layer 2, as described above. That is, inside the leak-proof layer 2, a part of the fiber (for example, one end of the fiber) jumps out from the fiber assembly 41B forming the meltblown layer 41, and the jumped-out fiber (raised fiber) 41A is the fiber of the protective layer 42. The portion having a structure that enters between 42A is referred to as "brushed region 6". The protective layer 42 containing the fibers of the meltblown layer 41 is preferably arranged on the non-absorption layer side 2B of the meltblown layer 41.

  The laminated structure of the leakproof layer 2 is not limited to the form of a two-layer structure as shown in FIG. 3, and has a structure of three or more layers as long as the protective layer 42 is provided at least on the non-absorption layer side 2B. May be. For example, as shown in FIG. 4, in addition to the protective layer 42 on the non-absorbent layer side 2B, the melt blown layer 41 may be provided with another protective layer 43 on the absorbent layer side 2A. Alternatively, although not shown, the meltblown layer 41 may be composed of two or more layers, and each of the protective layers 42 and 43 may be composed of two or more layers. However, from the viewpoint of maintaining the softness of the leak-proof layer 2, the leak-proof layer 2 has the smallest possible number of layers and contains 2.5 fibers / mm of the melt-blown layer 41 in the protective layer 42. It is preferable to include the napped region 6 ″ which is the above (see the partially enlarged views in the circle indicated by the symbol P in FIGS. 3 and 4).

  Due to the above-mentioned raised region 6 inside the leakproof layer 2, some fibers of the meltblown layer 41 stand up and the fibers of the leakproof layer 2 are raised without excessively increasing the fiber amount of the leakproof layer 2. Arranged to fill the interspace. As a result, the leak-proof layer 2 has a high liquid-leakage preventive property, with the through-holes in the thickness direction being blocked, without impairing the softness.

  Setting the number of fibers entering the raised area 6 of the leakproof layer 2 to be 2.5 fibers / mm or more means the number of fibers that close the above-mentioned through holes from the viewpoint of liquid leakage prevention.

  The number of fibers entering the protective layer 42 from the melt blown layer 41 in the napped region 6 is preferably 5 fibers / mm or more, more preferably 10 fibers / mm or more, from the viewpoint of liquid leakage prevention. From the viewpoint of air permeability, the number of fibers to be incorporated is preferably 100 fibers / mm or less, more preferably 50 fibers / mm or less, and further preferably 40 fibers / mm or less. Specifically, the number of fibers entering the protective layer 42 from the melt blown layer 41 in the napped region 6 is preferably 2.5 fibers / mm or more and 100 fibers / mm or less, and more preferably 5 fibers / mm or more and 50 fibers / mm or less. It is preferably 10 lines / mm or more and 40 lines / mm or less.

(Measurement method for the number of fibers in the meltblown layer that has entered the protective layer)
The number of fibers of the meltblown layer 41 that has entered the protective layer 42 can be measured by the following method.
When taking out the leak preventive layer from the commercially available absorbent article, the leak preventive layer 2 in the region overlapping with the absorbent layer is taken out in accordance with the method described in the above (Method for measuring through-hole). The taken out leakproof layer 2 is cut in the thickness direction to obtain a cross section. The leak-proof layer 2 is placed on an observation table so that the cross section faces upward, and the cut surface is observed using an SEM at an observation magnification of 100 times.
Regarding the length of the field of view to be observed (the length in the plane direction in the cross section of the leakproof layer), one field of view when observing the leakproof layer with an SEM is 1 mm, and 10 points are measured. For each location, the number of napped fibers 41A that enter the protective layer 42 on the non-absorption layer side 2B from the meltblown layer 41 is counted. The sum of the numbers counted at the above 10 places is used as a numerator, and the numerator is calculated according to the following formula [2].
(Number of fibers in the meltblown layer that have entered the protective layer 42)
= (The number of fibers of the meltblown layer 41 entering the protective layer 42 in the observation field)
/ L (length (10 mm) of the interface between the protective layer 42 and the meltblown layer 41 in the observation visual field) [2]

An example of the cut surface in the thickness direction to be observed is an SEM image as shown in FIG. In the cross section of the leakproof layer 2 shown in FIG. 5, a three-layer structure of a protective layer (spun bond layer) 43 on the absorbent layer side 2A, a melt blown layer 41 and a protective layer (spun bond layer) 42 on the non-absorbent layer side 2B is shown. Has been done. In the SEM image of FIG. 5, the raised fibers 41A protruding from the fiber assembly 41B forming the meltblown layer 41 enter between the fibers 42A of the protective layer 42 on the non-absorption layer side 2B.
The fibers of the meltblown layer 41 that enter the protective layer 42 are preferably as shown in, for example, the SEM image shown in FIG. 6 when observed from the surface 22 on the non-absorption layer side 2B. That is, as shown in the frame area surrounded by the one-dot chain line in the SEM image of FIG. 6, the napped fibers 41A of the meltblown layer 41 are entangled with the fibers 42A of the protective layer 42 while entering between the fibers 42A of the protective layer 42. It is preferable that the state is As a result, the entry of the raised fibers 41A of the meltblown layer 41 into the protective layer 42 is more stably maintained.

  In FIG. 5, as shown in FIG. 4, protective layers 42 and 43 are arranged on both surfaces of the meltblown layer 41. In this case, it is preferable that the napped region 6 be arranged on the non-absorption layer side 2B as shown in FIG. This is to maintain the state of the napped fibers from the viewpoint of liquid leakage prevention. More specifically, the purpose is to protect the fiber structure of the napped region 6 from the pressure of the liquid that moves from the absorbent layer 3 and prevent the formation of through holes when the absorbent article is used. The raised region 6 may be arranged on both the non-absorption layer side 2B and the absorption layer side 2A.

  In addition, from the viewpoint of liquid leakage prevention property, the napped region 6 is preferably arranged in the entire region of the leak preventive layer 2 that overlaps with the absorbent layer 3. Furthermore, it is more preferable that the napped region 6 is arranged so as to extend from a region that overlaps with the absorbent layer 3 to a flat region that does not overlap with the absorbent layer 3 beyond the region.

In the leakproof layer 2, it is preferable that the fibers of the meltblown layer 41 are not exposed on the surface of the non-absorption layer side 2B (the surface of the surface 22). As the mode in which the fibers of the meltblown layer 41 are not exposed, for example, the thickness of the protective layer 42 on the non-absorption layer side 2B of the meltblown layer 41 may be set to a predetermined value, or the fibers may be fixed using hot melt or the like. it can.
Thus, the fibers of the meltblown layer 41 are not exposed on the surface of the non-absorption layer side 2B (the surface of the surface 22), so that the fibers of the meltblown layer 41 that have been napped are protected and the fiber structure of the napped region 6 becomes By being held, the liquid hardly leaks from the leak-proof layer 2.
(How to check if the fibers of the meltblown layer are exposed on the surface of the leakproof layer)
The presence or absence of the above-described exposure can be confirmed by observing the surface of the observation target with an SEM at an observation magnification of 100 times.
When the fibers of the meltblown layer 41 are reflected on the outermost surface of the observation screen, it is determined that the fibers of the meltblown layer are exposed on the surface. Otherwise, for example, when only the fibers of the protective layer are reflected on the outermost surface of the observation screen, it is determined that the fibers are not exposed.

  The "meltblown layer" here is a fiber layer (spin-bonded non-woven fabric layer) formed by spinning a thermoplastic resin heated and melted by a so-called meltblown method and depositing it on a conveyor to form a nonwoven fabric. In the melt blown method, the molten resin discharged from the nozzle of the spinneret is blown off by a jet stream of high-temperature gas to tear it off to form ultrafine cotton-like fibers. Therefore, the obtained meltblown layer is a layer of a non-woven fabric made of ultrafine fibers having a fiber diameter of 10 μm or less. The constituent fibers are long fibers having a fiber length of 30 μm or more. The fiber spacing is also small. Such a meltblown layer 41 has excellent texture and barrier properties. On the other hand, with respect to strength and wear resistance, reinforcement with the protective layer 42 is required.

  The average fiber diameter (R1) of the fibers of the meltblown layer 41 is preferably 2.5 μm or less, more preferably 1.5 μm or less, and further preferably 1 μm or less, from the viewpoint of excellent liquid leakage prevention. Moreover, 0.1 μm or more is realistic. Specifically, the average fiber diameter (R1) of the fibers of the meltblown layer 41 is preferably 0.1 μm or more and 2.5 μm or less, more preferably 0.1 μm or more and 1.5 μm or less, and even more preferably 0.1 μm or more and 1 μm or less. preferable. In the laminated structure of the meltblown layer 41 and the protective layer 42 of the leakproof layer 2, the space between the fibers is further narrowed by suppressing the average fiber diameter (R1) of the fibers of the meltblown layer 41 within the above range. Therefore, it is possible to more surely eliminate the above-described through hole.

  The protective layer 42 is a fiber layer that supplements the strength and the like of the meltblown layer 41, and is preferably made of fibers having a larger fiber diameter than the meltblown layer 41. As the protective layer 42, various fiber layers can be used as long as they can supplement the strength and the like of the meltblown layer 41. Among them, the protective layer 42 is preferably a spunbond layer from the viewpoint of cost.

  The "spunbond layer" here is a layer of a non-woven fabric manufactured by a so-called spunbond method, and like the meltblown layer, it is a fiber layer obtained by spinning a heat-melted thermoplastic resin and depositing it on a conveyor. .. However, in the spunbond method, fibers are formed while cooling and drawing the molten resin discharged from the nozzle from the spinning port. The obtained spunbond layer is a fiber layer composed of fibers (filaments) having a larger fiber diameter and longer fiber length than the fibers of the meltblown layer. After the spunbond layer is laminated on the meltblown layer, hot embossing is preferably performed to form a nonwoven fabric in which both are integrated.

  From the viewpoint of more reliably preventing the above-described through holes in the leakproof layer 2, the viewpoint of increasing the number of fibers of the meltblown layer 41 entering the protective layer 42 in the raised region 6, and the meltblown of the protective layer 42. From the viewpoint of more effectively protecting the layer 41, the average fiber diameter (R1) of the fibers of the meltblown layer 41 is preferably smaller than the average fiber diameter (R2) of the fibers of the protective layer 42. From these viewpoints, the ratio (R1 / R2) of the average fiber diameter (R1) of the fibers of the meltblown layer 41 to the average fiber diameter (R2) of the fibers of the protective layer 42 is preferably 1/8 or less, and is 1/20. The following is more preferable, and 1/25 or less is further preferable. Further, the ratio (R1 / R2) is preferably 1/100 or more, more preferably 1/50 or more, still more preferably 1/40 or more, from the viewpoint of air permeability. Specifically, the ratio (R1 / R2) is preferably 1/100 or more and 1/8 or less, more preferably 1/50 or more and 1/20 or less, and further preferably 1/40 or more and 1/25 or less.

(Measurement method of average fiber diameter)
Five small sample pieces are randomly collected from the melt-blown layer of the leakproof layer, and an SEM is used to take a photograph in which the observation magnification is enlarged to, for example, 1000 to 10000 times so that 20 to 60 fibers are reflected in the visual field. It is obtained by measuring the fiber diameter so that all the fibers in the visual field are counted once, and rounding off the first decimal place of the average value to calculate.

The melt blown layer 41 preferably has a filling rate of 25% or less, more preferably 20% or less, and more preferably 10% or less, from the viewpoint of maintaining the softness while closing the through holes of the leak preventive layer 2. It is more preferable that the amount is 5% or less. The "filling ratio" here is the ratio of the fibers per space. By controlling the filling rate of the meltblown layer 41 within the above range, the meltblown layer 41 has a softness such as a cloth that can cause a gentle curved surface or folds (high drapeability), and has a softness such as paper or film. Hardness such as crispness. For example, hardness that requires a certain amount of force when bending, etc., and is easy to bend instead of bending when twisting. Dry rubbing that occurs when touching or twisting Sound.) Can be suppressed.
The filling rate of the meltblown layer 41 is preferably 2% or more, more preferably 2.5% or more, still more preferably 3% or more, from the viewpoint of leakproofness. Specifically, the filling rate of the meltblown layer 41 is preferably 2% or more and 25% or less, more preferably 2% or more and 20% or less, further preferably 2.5% or more and 10% or less, and 3% or more and 5% or less. Is particularly preferable.

(Measurement method of melt blown layer filling rate)
The filling rate of the meltblown layer can be measured by the following method.
The mass of the leakproof layer to be measured is measured. Further, the cross section in the thickness direction of the leakproof layer is observed using the SEM described above, and the thickness of the meltblown layer is measured. The meltblown layer is taken out based on (Method for measuring basis weight of meltblown layer) described later. Then, the basis weight is calculated and calculated by {grammage of meltblown layer / (thickness of meltblown layer × density of resin)} × 100.
The "resin density" can be measured by the following method.
That is, the taken out melt blown layer was pressed with a lab press (manufactured by Toyo Seiki Seisakusho Co., Ltd., model P2-30) at 180 ° C. for two minutes with a two-stage press (low pressure: 5 kg / cm ³ , high pressure: 150 kg / cm ³ ). Afterwards, a film is prepared by applying a cooling press for 1 minute. Then, it is calculated by cutting into 10 × 10 cm from the place where air is not mixed, measuring the mass, and dividing by the volume.

The basis weight of the meltblown layer 41, in order to ensure the softness, preferably 20 g / ^{m 2} or less, more preferably 15 g / ^{m 2} or less, more preferably 10 g / ^{m 2} or less. The basis weight of the meltblown layer 41, in order to ensure the sheet strength, 3 g / ^{m 2} or more is preferable, 4g / ^{m 2} or more preferably, 5 g / ^{m 2} or more is more preferable. Specifically, the basis weight of the meltblown layer 41 is preferably 3 g / m ² or more and 20 g / m ² or less, more preferably 4 g / m ² or more and 15 g / m ² or less, and 5 g / m ² or more and 10 g / m ² or less. Is more preferable.

(Method of measuring the basis weight of the meltblown layer)
The basis weight of the meltblown layer can be measured by the following method.
The mass of the leak-proof layer to be measured is measured in a dry state. Furthermore, the cross section in the thickness direction of the leak preventive layer is observed using the SEM described above, and the thickness and the ratio of the thicknesses of the melt blown layer and the protective layer are measured. The following means are used to peel off the meltblown layer from the leakproof layer. If the meltblown layer and the protective layer are bonded together with hot melt, etc., use a cold spray to carefully peel off the meltblown layer. Then, the mass of the meltblown layer is measured and divided by the sheet area of the leakproof layer to calculate the basis weight of the meltblown layer. If the meltblown layer and the protective layer are heat-bonded to each other by embossing, remove the embossed portion and then carefully peel off the meltblown layer with your hands or tweezers. Then, the mass of the meltblown layer is measured and divided by the value obtained by subtracting the area of the embossed portion from the sheet area of the leakproof layer to calculate the basis weight of the meltblown layer.

Next, a preferred method of manufacturing the nonwoven fabric which will be the leak-proof layer 2 of the present embodiment will be described. Here, a case where the protective layer 42 is a spun bond layer will be described.
The meltblown layer 41 deposits ultrafine fibers on a belt conveyor by the meltblown method, and continuously conveys the raw material of the meltblown layer in the machine flow direction. At that time, the fiber diameter, the filling rate, and the basis weight described above can be obtained by setting various conditions such as the nozzle diameter of the spinneret, the wind velocity of the jet stream of high-temperature gas, and the temperature. Next, a spunbond layer original material is laminated as a protective layer 42 on the surface of the meltblown layer original material by a spunbond method. At that time, it is preferable to perform a raising treatment on the surface of the raw material of the meltblown layer upstream of the layer of the raw material of the spunbond layer. As a result, the spunbond layer original fabric is laminated on the raised surface of the meltblown layer original fabric to form the aforementioned raised region 6.

  The raising treatment can be carried out by various methods usually used in the method for producing a nonwoven fabric. For example, it is carried out by rotating a convex roll having a plurality of convex portions on the peripheral surface while contacting the surface of the raw material of the melt blown layer. Thereby, the raised fiber can be formed.

  After the raising treatment, fibers to be the original fabric of the spunbond layer, which are discharged and cooled and drawn by the spunbond method, are deposited on the raised face of the raw material of the meltblown layer. As a result, the napped fibers of the meltblown layer original fabric enter between the fibers of the spunbond layer original fabric, and the napped region 6 in the leak-proof layer 2 of the present embodiment is formed. Thereby, the nonwoven fabric which becomes the leakproof layer 2 of this embodiment is manufactured.

  In this manufacturing method, the structure of “2.5 or more fibers of the meltblown layer entering the protective layer” in the napped region 6 is a part of the fiber from the fiber assembly 41B constituting the meltblown layer 41. (For example, one end portion of the fiber) pops out, and the popped-out fiber (raised fiber) 41A enters between the fibers 42A of the protective layer 42 on the non-absorption layer side 2B. Further, in the method for producing the nonwoven fabric which becomes the leak-proof layer 2 of the present embodiment, desired average fiber diameter, filling rate, basis weight, etc. can be obtained by appropriately setting various production conditions.

In the above manufacturing method, a protective layer 43 made of a spun bond layer may be further provided on the surface of the raw material of the melt blown layer which is the absorption layer side 2A. In this case, the same process for producing the raw material for the spunbond layer may be further provided upstream of the process for producing the raw material for the meltblown layer. In this case, the meltblown layer original fabric will be formed on the upstream spunbond layer original fabric.
Further, as the method for producing the absorbent article of the present invention, it is preferable that the nonwoven fabric obtained by the above-mentioned production method is used as a leak-proof layer and directly laminated on the absorbent layer. The absorbent article of the present invention is manufactured by laminating a surface layer on the skin contact surface side of the absorbent layer and integrating the directly laminated absorbent layer and leak preventive layer (nonwoven fabric). At that time, if necessary, there may be a step of incorporating other constituent members.

  The constituent fibers of the meltblown layer 41 of the leakproof layer 2 and the constituent fibers when the protective layers 42 and 43 are spunbond layers are composed of a thermoplastic resin. Examples of the thermoplastic resin include one or more selected from polyolefin resins, polyester resins, polyamide resins, acrylonitrile resins, vinyl resins, vinylidene resins, and the like. Examples of the polyolefin resin include one or more selected from polyethylene, polypropylene, polybutene and the like. Examples of the polyester resin include one or more selected from polyethylene terephthalate, polybutylene terephthalate, and the like. Examples of the polyamide resin include one or more selected from nylon and the like. Examples of the vinyl resin include polyvinyl chloride. Examples of the vinylidene resin include polyvinylidene chloride. It is also possible to use a modified product or mixture of these various resins.

  Regarding the above-described embodiment, the present invention further discloses the following absorbent articles, nonwoven fabric manufacturing methods, and absorbent article manufacturing methods.

<1>
An absorbent article having a surface layer, a leakproof layer, and an absorbent layer arranged between the surface layer and the leakproof layer,
The leakproof layer is directly laminated to the absorption layer,
The leakproof layer has a meltblown layer and a protective layer of the meltblown layer,
An absorbent article having one or more selected from the following (i) and (ii).
(I) The leak-proof layer has an embossed portion in which both layers are joined and a non-embossed portion other than the embossed portion,
The leakproof layer has a non-opening region in the non-embossed portion,
The non-perforated region, when viewed in plan view of the leak-proof layer, is a through-hole in which an interfiber space including a region in which a rectangular area having a diagonal length of 10 μm is 25 μm ² or more penetrates in the thickness direction, Is an area that does not have
The non-opened region is arranged in a region where the leak preventive layer overlaps with the absorption layer.
(Ii) the protective layer is arranged on the non-absorption layer side of the melt blown layer,
The leak-proof layer has a raised region in which 2.5 fibers / mm or more of the fibers of the melt-blown layer, which have entered the protective layer,
The average fiber diameter of the fibers of the meltblown layer is 2.5 μm or less,
The raised area is arranged in an area where the leak preventive layer overlaps with the absorbent layer.
<2>
An absorbent article having a surface layer, a leakproof layer, and an absorbent layer arranged between the surface layer and the leakproof layer,
The leakproof layer is directly laminated to the absorption layer,
The leak-proof layer has a melt blown layer and a protective layer of the melt blown layer, and has an embossed portion in which both layers are joined and a non-embossed portion other than the embossed portion,
The leakproof layer has a non-opening region in the non-embossed portion,
The non-perforated region, when viewed in plan view of the leak-proof layer, is a through-hole in which an interfiber space including a region in which a rectangular area having a diagonal length of 10 μm is 25 μm ² or more penetrates in the thickness direction, Is an area that does not have
The non-opened area is an absorbent article, wherein the leak-proof layer is arranged in an area overlapping with the absorbent layer.

<3>
The absorbent article according to <1> or <2>, wherein the fibers of the meltblown layer have an average fiber diameter of 2.5 μm or less.
<4>
The absorbent article according to any one of <1> to <3>, wherein the protective layer is arranged on the non-absorbent layer side of the meltblown layer.

<5>
An absorbent article having a surface layer, a leakproof layer, and an absorbent layer arranged between the surface layer and the leakproof layer,
The leakproof layer is directly laminated to the absorption layer,
The leak-proof layer has a melt blown layer and a protective layer of the melt blown layer, the protective layer is arranged on the non-absorption layer side of the melt blown layer,
The leak-proof layer has a raised region in which 2.5 fibers / mm or more of the fibers of the melt-blown layer, which have entered the protective layer,
The average fiber diameter of the fibers of the meltblown layer is 2.5 μm or less,
The absorbent article, wherein the raised area is arranged in an area where the leak-proof layer overlaps with the absorbent layer.

<6>
The absorbent article according to any one of <1> to <5>, wherein the raised region or the non-opened region is arranged in the entire region of the leak-proof layer that overlaps with the absorbent layer.
<7>
The absorbent article according to any one of <1> to <6>, wherein the fibers of the meltblown layer are not exposed on the surface of the leakproof layer on the non-absorption layer side.
<8>
The absorbent article according to any one of <1> to <7>, wherein the melt blown layer has a fiber packing rate of 25% or less.
<9>
The absorbent article according to any one of <1> to <8>, wherein the melt blown layer has a basis weight of 20 g / m ² or less.

<10>
Any of the above <1> to <9>, wherein the leak-proof layer and the absorbent layer are laminated without any other layer being present between them, except for the agent used for joining the two. The absorbent article according to item 1.
<11>
The absorbent article according to any one of <1> to <10>, wherein the leak-proof layer forms a layer on the most non-skin contact surface side of the absorbent article.
<12>
The absorbent article according to any one of <1> to <11>, which does not have a film on the non-skin contact surface side of the absorbent layer.
<13>
The said leak-proof layer is an absorbent article any one of said <1>-<12> which has a fiber layer as a component.
<14>
The leak-proof layer comprises, in addition to the protective layer on the non-absorbent layer side, another protective layer on the absorbent layer side, with respect to the meltblown layer, according to any one of the above items <1> to <13>. Sex goods.
<15>
The absorbent article according to <14>, wherein the napped region is arranged not only on the non-absorption layer side but also on the absorption layer side.

<16>
The number of fibers entering the protective layer on the non-absorption layer side from the meltblown layer is preferably 2.5 fibers / mm or more and 100 fibers / mm or less, more preferably 5 fibers / mm or more and 50 fibers / mm or less, and 10 fibers. / Mm or more and 40 / mm or less is further preferable, The absorbent article any one of said <1>-<15>.
<17>
The absorbent article according to any one of the above items <1> to <15>, wherein the number of fibers entering the protective layer on the non-absorption layer side from the meltblown layer is 10 fibers / mm or more and 40 fibers / mm or less. ..
<18>
Any of the above <1> to <17>, wherein the napped region or the non-perforated region is arranged extending from a region overlapping with the absorbent layer to a flat region beyond the region not overlapping with the absorbent layer. The absorbent article according to 1.

<19>
The average fiber diameter of the fibers of the meltblown layer is preferably 0.1 μm or more and 2.5 μm or less, more preferably 0.1 μm or more and 1.5 μm or less, further preferably 0.1 μm or more and 1 μm or less, and the above <1> to << The absorbent article according to any one of 18>.
<20>
The absorbent article according to any one of <1> to <18>, wherein the fibers of the meltblown layer have an average fiber diameter of 0.1 μm or more and 1 μm or less.

<21>
The absorbent article according to any one of <1> to <20>, wherein an average fiber diameter of fibers of the meltblown layer is smaller than an average fiber diameter of fibers of the protective layer.
<22>
The ratio of the average fiber diameter of the fibers of the melt blown layer to the average fiber diameter of the fibers of the protective layer is preferably 1/100 or more and 1/8 or less, more preferably 1/50 or more and 1/20 or less, and 1/40. The absorbent article according to any one of the above items <1> to <21>, further preferably not less than 1/25.
<23>
The ratio of the average fiber diameter of the fibers of the melt blown layer to the average fiber diameter of the fibers of the protective layer is 1/40 or more and 1/25 or less, according to any one of <1> to <21> above. Absorbent article.

<24>
2% or more and 25% or less is preferable, 2% or more and 20% or less is more preferable, 2.5% or more and 10% or less is further more preferable, and 3% or more and 5% or less of the fiber filling rate of the said meltblown layer is especially preferable. , The absorbent article according to any one of <1> to <23>.
<25>
The absorbent article according to any one of <1> to <23>, wherein a filling rate of fibers in the melt blown layer is 3% or more and 5% or less.

<26>
The basis weight of the meltblown layer is preferably 3 g / m ² or more and 20 g / m ² or less, more preferably 4 g / m ² or more and 15 g / m ² or less, and further preferably 5 g / m ² or more and 10 g / m ² or less, The absorbent article according to any one of <1> to <25>.
<27>
The absorbent article according to any one of <1> to <25>, wherein the basis weight of the meltblown layer is 5 g / m ² or more and 10 g / m ² or less.

<28>
By depositing ultrafine fibers on a belt conveyor by the melt blown method, the meltblown layer original fabric is continuously conveyed in the machine flow direction, and a raising treatment is applied to the surface of the meltblown layer original fabric, and the meltblown layer original fabric is raised. A method for producing a non-woven fabric, in which a spunbond layer original fabric is laminated on the surface that has been spunbonded.
<29>
The method for producing a nonwoven fabric according to <28>, wherein the raising process is performed by rotating a convex roll having a plurality of convex portions on the peripheral surface while contacting the surface of the raw material of the meltblown layer.
<30>
A process for producing a spunbond layer original fabric is further provided upstream of the process for producing the meltblown layer original fabric, and a protective layer made of a spunbond layer is further arranged on the surface of the meltblown layer original fabric which is the absorption layer side. The method for producing a nonwoven fabric according to <28> or <29>.
<31>
A method for producing an absorbent article, wherein a nonwoven fabric obtained by the method for producing a nonwoven fabric according to any one of <28> to <30> is directly laminated on an absorbent layer as a leak-proof layer.

  The present invention will be described in more detail based on the following examples, but the invention is not intended to be limited thereto.

(Example 1)
First, a spunbond layer raw material having an average fiber diameter of 20 μm and a basis weight of 9 g / m ² was formed by a spunbond method using a polyolefin resin.
A meltblown layer original fabric having a basis weight of 10 g / m ² was formed thereon by a meltblown method (spinning temperature of 270 ° C.) using a polyolefin resin. Raising treatment was applied to the entire surface of the original meltblown layer. Specifically, a sheet paper manufactured by Trusco Nakayama Co., Ltd., product number: GBS-600-5P is used to apply a pressure of 165 Pa to the meltblown layer original fabric once at 1.2 m / min. Rubbed against. The average fiber diameter, thickness and filling rate of the obtained meltblown layer are based on the above-mentioned (Measuring method of average fiber diameter), (Measuring method of filling rate of meltblown layer) and (Measuring method of basis weight of meltblown layer). Was measured.
Then, on the surface of the melt-blown layer original fabric that had been subjected to the raising treatment, a spunbond original fabric having an average fiber diameter of 20 μm and a basis weight of 9 g / m ² was formed by a spunbond method using a polyolefin resin.
Then, the laminated spunbond-meltblown-spunbond (SMS) fiber layer was subjected to hot embossing to obtain an SMS nonwoven fabric.
As a result, a leakproof layer sample of Example 1 in which the spunbond layers disposed on both surfaces of the meltblown layer 41 were used as the protective layers 42 and 43 was prepared.
In the obtained leak-proof layer sample, the number of fibers of the meltblown layer 41 that entered the protective layer from the napped surface of the meltblown layer 41 was measured on the surface of the spunbond layer on the napped side of the meltblown layer 41. The measurement was performed based on the above-mentioned (method for measuring the number of fibers that entered), and the results are shown in Table 1 (the same applies to Examples 2 and 3 below).
Similarly, in the obtained leak-proof layer sample, whether or not the fibers of the meltblown layer are exposed up to the surface of the spunbond layer on the surface of the spunbond layer on the raised side of the meltblown layer 41 is determined as described above ( Based on the method for confirming that the fibers of the meltblown layer are exposed on the surface of the leakproof layer, the results are shown in Table 1 (the same applies to Examples 2 and 3 below).

(Example 2)
A leak preventive layer sample of Example 2 was prepared in the same manner as in Example 1 except that the melt blown layer 41 shown in Table 1 was used. The above fiber diameter was realized by changing the spinning temperature of the meltblown layer in Example 1 to a low temperature (255 ° C).

(Example 3)
A leak preventive layer sample of Example 3 was prepared in the same manner as in Example 1 except that the melt blown layer 41 shown in Table 1 was used. The above fiber diameter was realized by changing the spinning temperature of the meltblown layer in Example 1 to 265 ° C.

(Comparative Example 1)
A leak preventive layer sample of Comparative Example 1 was prepared in the same manner as in Example 1 except that the melt blown layer 41 was not napped and was described in Table 1. It should be noted that the reason why the fibers that slightly penetrated were formed due to the pressure applied during the stacking even though the raising treatment was not performed.

(Comparative example 2)
A leak preventive layer sample of Comparative Example 2 was prepared in the same manner as in Example 2 except that the melt blown layer 41 was not napped and was described in Table 1.

(Comparative example 3)
A leak preventive layer sample of Comparative Example 3 was prepared in the same manner as in Example 1 except that the melt blown layer 41 was as described in Table 1. The fiber diameter was realized by changing the spinning temperature of the meltblown layer in Example 1 to a low temperature (250 ° C).
(Comparative example 4)
A leak preventive layer sample of Comparative Example 4 was prepared in the same manner as in Example 3 except that the melt blown layer 41 was not subjected to the raising treatment, and the filling rate was increased by the calendar treatment so as to be the one described in Table 1. ..

(Comparative example 5)
A spunbond layer original fabric and a meltblown layer original fabric similar to those in Example 2 were produced one by one, and in a state where both original fabrics were overlapped, a water flow was jetted twice from different sides of the meltblown layer original fabric side. .. The first injection is performed at a low pressure (2.5 MPa) using a nozzle with a diameter of 0.12 mm to entangle the constituent fibers of the spunbond layer original fabric and the meltblown layer original fabric, and wet both layers to make them familiar. It was The second injection is performed at a high pressure (5 MPa) using a nozzle having a diameter of 0.1 mm, and further entangles the constituent fibers of the spunbond layer original fabric and the meltblown layer original fabric to form two layers of spunbond-meltblown (SM). An SM nonwoven fabric was obtained.
As a result, a leak-proof layer sample of Comparative Example 5 in which the spunbond layer disposed on one surface of the meltblown layer 41 was used as the protective layer 42 was prepared. The thickness and filling rate of the meltblown layer were measured based on the above-mentioned (Method for measuring filling rate of meltblown layer) and (Method for measuring basis weight of meltblown layer).
In the leak-proof layer sample of Comparative Example 5, the number of fibers of the meltblown layer 41 that entered the protective layer 42 from the surface of the meltblown layer 41 was measured based on the above-mentioned (method for measuring the number of intruded fibers), It was set as 1.

(Comparative example 6)
A leak-proof layer sample of Comparative Example 6 was prepared in the same manner as Comparative Example 5 except that the pressure of the jet of water was 1.75 MPa for the first time and 3.5 MPa for the second time.

(Comparative Example 7)
A leak-proof layer sample of Comparative Example 7 was prepared in the same manner as Comparative Example 5 except that the pressure of the jet of water was 1 MPa for the first time and 2 MPa for the second time.

The following confirmations and tests were carried out on the leakproof layer samples of the above-mentioned Examples and Comparative Examples. The results are shown in Table 1.
(1) Liquid leak prevention test:
On the filter paper (No. 2, manufactured by Advantech Toyo Co., Ltd., diameter 70 mm), a sample of the leakproof layer cut into 8 cm × 8 cm was placed. At that time, the leak-proof layer sample was placed with the surface of the non-absorption layer side 2B (the surface with the raised region) facing the filter paper. On the leakproof layer sample, a dry pulp sheet (Lead Healthy Cooking Paper Double (trade name), basis weight 40 g / m ² manufactured by Lion Co., Ltd.) cut into 8 cm × 8 cm was placed.
Then, 1.0 g of deionized water containing 0.005% by mass of blue No. 1 was injected from above the dry pulp sheet using a dropper. After the injection, an acrylic plate having a diameter of 60 mm was overlaid, and a weight of 2 kg was used for pressing for 5 seconds.
After pressurizing for 5 seconds, the presence or absence of wetting on the filter paper (presence or absence of seepage) was confirmed by a method of visually confirming the coloration of the filter paper. In addition, the amount of deionized water that exuded on the filter paper was confirmed by subtracting the weight before the test from the weight after the test measured by an electronic balance.
The injected deionized water of 1.0 g is assumed to be in a state where the entire leak-proof layer is wet by the liquid transferred from the absorbent layer to the leak-proof layer in the absorbent article. The load of the weight of 2 kg is based on the assumption that the absorbent article is mounted and seat pressure is applied.
(2) Softness test:
Five panels (persons engaged in research in the field of absorbent articles) were manually stroked the surface (both sides) of each non-woven fabric sample to perform sensory evaluation of softness. For evaluation, each panel was given a score based on the following evaluation criteria, and the average value of the evaluation scores of 5 persons was used as the score of the softness sensory evaluation of each sample.
Disposable diapers (Kao Corporation: Marys (registered trademark) Mary's Pants M size, made in 2017) dissolve the hot melt by using an organic solvent (butyl acetate), and the outermost (non-skin side) The non-woven fabric and the film as the leakproof layer were removed and dried for one day in a draft before use. The softness of each non-leakable layer sample was quantified in 5 steps, where the softness of the outermost (non-skin side) non-woven fabric is 5 points and the softness of the film as the leakproof layer is 1 point. ..

As shown in Table 1 above, the melt-blown layer entering the protective layer has a protective layer rather than the leak-proof layer samples of Comparative Examples 1, 2 and 4 in which less than 2.5 fibers / mm had through holes. The leak-proof layer samples of Examples 1 to 3 in which the number of fibers of the melt-blown layer entering were 2.5 fibers / mm or more and did not have through holes were excellent in the liquid leakage prevention property. Similarly, in comparison with the leak-proof layer samples of Comparative Examples 3 and 5 to 7 in which the fibers of the meltblown layer that penetrated into the protective layer had 2.5 holes / mm, the through holes were not formed. The leak-proof layer samples of Examples 1 to 3 which did not have excellent liquid leakage preventive property.
In particular, the leakage-barrier layer samples of Examples 1 to 3 had markedly higher liquid leakage prevention properties as compared with the leakage-barrier layer samples of Comparative Examples 5 to 7. This is because in Comparative Examples 5 to 7, the fibers of the meltblown layer were moved by the pressure of the water flow and the through holes of 25 μm ² or more were formed by forming the napped region by the hydroentangling method, while Examples 1 to 3 were formed. It is because the raised area was formed by the raising treatment and the movement of the fibers of the meltblown layer could be suppressed by the hot embossing treatment. This is also because the leak-proof layer samples of Examples 1 to 3 could prevent the fibers of the meltblown layer from being exposed to the surface of the leak-proof layer on the non-absorption layer side.
In addition, in Examples 1 to 3, it was found that softer touch can be realized by suppressing the filling rate of the meltblown layer.

1 Surface Layer 2 Leak-Proof Layer 3 Absorption Layer 4 Fiber Layer 6 Raised Area 2A Absorption Layer Side of Leak-Proof Layer 2B Non-Absorption Layer Side of Leak-Proof Layer 21 Surface of Absorption Layer Side of Leak-Proof Layer 22 Non-Absorption Layer Layer side surface 41 Melt blown layer 41A Melt blown layer raised fibers 42, 43 Protective layer 42A Protective layer fiber 48 Fiber 49 Space 10 Absorbent article

Claims (7)

An absorbent article having a surface layer, a leakproof layer, and an absorbent layer arranged between the surface layer and the leakproof layer,
The leakproof layer is directly laminated to the absorption layer,
The leak-proof layer has a melt blown layer and a protective layer of the melt blown layer, and has an embossed portion in which both layers are joined and a non-embossed portion other than the embossed portion,
The leakproof layer has a non-opening region in the non-embossed portion,
The non-perforated region has a through-hole in which an interfiber space including a region in which a rectangular area having a diagonal length of 10 μm has an area of 25 μm ² or more when the leak-proof layer is viewed in plan view penetrates in the thickness direction. Is an area that does not have,
The non-perforated region is an absorbent article, wherein the leak-proof layer is arranged in the entire region overlapping with the absorbent layer.   The absorbent article according to claim 1, wherein the fibers of the meltblown layer have an average fiber diameter of 2.5 μm or less. An absorbent article having a surface layer, a leakproof layer, and an absorbent layer arranged between the surface layer and the leakproof layer,
The leakproof layer is directly laminated to the absorption layer,
The leak-proof layer has a melt blown layer and a protective layer of the melt blown layer, and has an embossed portion in which both layers are joined and a non-embossed portion other than the embossed portion,
The protective layer is arranged on the non-absorption layer side of the melt blown layer,
The leak-proof layer has a raised region in which 2.5 fibers / mm or more of the fibers of the melt-blown layer, which have entered the protective layer,
The average fiber diameter of the fibers of the meltblown layer is 2.5 μm or less,
The absorbent article, wherein the raised area is arranged in an area where the leak-proof layer overlaps with the absorbent layer.   The absorbent article according to any one of claims 1 to 3, wherein the fibers of the meltblown layer are not exposed on the surface of the leakproof layer on the non-absorption layer side.   The absorbent article according to any one of claims 1 to 4, wherein a fiber filling rate of the meltblown layer is 25% or less. The absorbent article according to claim 1, wherein the melt-blown layer has a basis weight of 20 g / m ² or less.   By depositing ultrafine fibers on a belt conveyor by the melt blown method, the meltblown layer original fabric is continuously conveyed in the machine flow direction, and a raising treatment is applied to the surface of the meltblown layer original fabric, and the meltblown layer original fabric is raised. A method for producing a non-woven fabric, in which a spunbond layer original fabric is laminated on the surface that has been spunbonded.