JP4711945B2 - Absorbent manufacturing method and manufacturing apparatus - Google Patents

Description

  The present invention relates to an absorbent body manufacturing method and manufacturing apparatus.

  Absorbent articles such as disposable diapers generally include a liquid-permeable top sheet, a liquid-impermeable or water-repellent back sheet, and a liquid-retaining absorbent body disposed between both sheets. The absorbent body is generally configured by covering a liquid-retaining absorbent core with a liquid-permeable core wrap sheet. The absorbent core is generally formed by dispersing an absorbent polymer on a fiber assembly made of a fiber material such as pulp fiber.

  Recently, in absorbent articles, the thickness of the absorber has been reduced (see Patent Document 1).

  For manufacturing the absorber, a product including a rotating drum having a plurality of recesses for accumulation on the outer peripheral surface and a duct for supplying the raw material of the absorber in a scattered state to the outer peripheral surface of the rotating drum. A fiber device is widely used, and when manufacturing an absorbent body including a fiber material and an absorbent polymer, the fiber material and the absorbent polymer are sequentially introduced into the duct from different locations as raw materials for the absorbent body. (For example, refer to Patent Document 2).

JP-A-10-118117 JP-A-10-137286

However, if the thickness of the absorber is simply made thinner than that of the conventional product, the absorption performance is inferior. For this reason, it is conceivable to increase the content of the absorbent polymer to supplement the absorption performance.However, when the fiber material is reduced to reduce the thickness and the content of the absorbent polymer is increased, the dispersion of the polymer is reduced. Due to the fact that the degree is not so high, a “sharp feeling” due to the rubbing of the polymers occurs, and the wearing feeling becomes poor.
As the thickness of the absorber becomes thinner, the dispersibility of the polymer affects the above-described “sharp feeling” and the like, so the conventional absorber manufacturing method avoids the above-mentioned problems such as “sharp feeling”. However, it is difficult to further reduce the thickness of the absorber. .

  Therefore, an object of the present invention is to improve the dispersibility of the absorbent polymer, and for example, a method and an apparatus for manufacturing an absorbent body that can be preferably used for the production of an absorbent body that is thin and does not produce a sharp feeling. Is to provide.

  The present invention is a method for producing an absorbent body comprising a step of introducing an absorbent polymer into an air flow and depositing the dispersed absorbent polymer in a predetermined shape to obtain an absorbent core, The object is achieved by providing a method for producing an absorbent body in which an absorbent polymer is introduced from two locations separated in a direction perpendicular to the flow direction of the air flow.

  The present invention includes a rotating drum in which a plurality of concave portions for accumulation are formed at predetermined intervals on the outer peripheral surface, and a duct for supplying the fiber material and the absorbent polymer, which are respectively scattered, to the outer peripheral surface of the rotating drum. An absorbent body manufacturing apparatus in which polymer inlets for introducing the absorbent polymer into the duct are formed at two locations on both sides in the longitudinal direction of the duct. This achieves the object.

  According to the manufacturing method and manufacturing apparatus of the absorber of the present invention, the dispersibility in the planar direction of the absorbent polymer in the absorber can be improved. Therefore, for example, it can be preferably used for the production of an absorber that is thin and does not produce a sharp feeling.

Hereinafter, the present invention will be described based on preferred embodiments thereof.
As shown in FIG. 1, an absorbent body manufacturing apparatus 10, which is an embodiment of an absorbent body manufacturing apparatus according to the present invention, includes a rotary drum 20 having a plurality of accumulation recesses 21 formed at predetermined intervals on an outer peripheral surface. The duct 30 includes an end portion that covers a part of the outer peripheral surface of the rotating drum 20 and supplies the scattered raw material of the absorber to the outer peripheral surface of the rotating drum 20.

  The rotary drum 20 has a cylindrical shape and is driven to rotate in the direction of arrow A in FIG. On the outer peripheral surface of the rotating drum 20, accumulation recesses 21, 21... Having a shape corresponding to the shape of the absorbent core to be manufactured are formed. An intake fan (not shown) is connected to the rotary drum 20, and the partitioned spaces B and C in the rotary drum are maintained at a negative pressure by driving the intake fan. A large number of pores (not shown) are formed in the bottom surface portion of each accumulation recess 21, and while the accumulation recess passes through the space maintained at a negative pressure, the accumulation recess The pores on the bottom surface of each function as suction holes.

Near the end of the duct 30 opposite to the rotating drum 20 side, a fiber material supply device (not shown) that supplies the fiber material 22 such as pulp fibers in a scattered state into the duct 30 is provided. . Further, a polymer introduction port 31 for introducing the absorbent polymer 3 into the duct 30 is provided between the rotary drum 20 and the fiber material introduction site in the duct 30.
As shown in FIGS. 2 and 3, the duct 30 has an internal space having a rectangular cross section surrounded by an upper surface 32, a lower surface 33, and a pair of side surfaces 34, 34. As shown in FIG. 1, the internal space of the duct 30 gradually passes from the introduction portion of the fiber material to the intermediate portion between the introduction portion of the absorbent polymer and the rotary drum 20 through the introduction portion of the absorbent polymer. It expands in the vertical direction, and in the vicinity of the rotary drum 20, it expands rapidly in the vertical direction. On the other hand, the pair of side surfaces 34, 34 of the duct 30 are substantially parallel to each other over substantially the entire length of the drum. Hereinafter, the upper surface 32, the lower surface 33, and the side surface 34 constituting the inner wall surface of the duct 30 are referred to as the upper surface 32, the lower surface 33, and the side surface 34 of the duct 30, respectively.

  The absorbent body manufacturing apparatus 10 is configured to introduce the absorbent polymer 3 into the duct 30 from two polymer inlets 31 formed on two sides in the longitudinal direction X of the duct 30. Specifically, the polymer introduction ports 31 are provided at two locations on both sides of the upper half of the internal space of the duct 30, and more specifically, as shown in FIG. It is formed in the vicinity of intersections 35 and 35 with 34 and 34. The polymer inlet 31 opens in a rectangular shape on the inner wall surface of the duct 30. In the example shown in FIGS. 1 to 3 and 5, the polymer inlet 31 is formed near the upper surface 32 of the pair of side surfaces 34, 34 of the duct 30. The flow direction of the air flow that conveys the fiber material 22 is the same as the longitudinal direction X of the duct 30.

As shown in FIG. 2, a pocket-shaped connecting member 36 is attached to the outer wall surface of the duct 30 in the portion where the polymer introduction port 31 is formed. The pocket-shaped connecting member 36 can be fixed by inserting one end portion of the polymer supply pipe 37. The other end of the polymer supply pipe 36 is connected to a polymer container 38. The polymer accommodated in the polymer accommodating portion 38 is divided into two polymer supply pipes 37 in equal amounts, and each is introduced into the duct from the polymer introduction port 31.
The movement of the polymer from the polymer accommodating portion 38 to the polymer inlet 31 is mainly a natural fall due to gravity, and no blowing means such as an air supply fan is provided on the polymer accommodating portion 38 side. The start and stop of the introduction of the polymer from the polymer introduction port 31 can be performed by a feeder operation of the polymer supply auger.

  The absorbent body manufacturing apparatus 10 further includes a first core wrap sheet supply mechanism for supplying the first core wrap sheet 5B onto the outer peripheral surface of the rotating drum 20 before the raw material is deposited in the accumulation recesses 21, and an accumulation purpose. A second core wrap sheet supply mechanism that supplies the second core wrap sheet 5A onto the outer peripheral surface of the rotating drum 20 after the raw material is deposited in the recess 21; Two adhesive coating apparatuses 6A and 6B for applying an adhesive to the second core wrap sheets 5A and 5B, respectively, are provided.

  Examples of the coating mode of the adhesive by the adhesive coating apparatuses 6A and 6B include solid coating, spray coating, spiral, stripe, and dot pattern coating, and the like, which are incorporated in absorbent articles such as disposable diapers. Sometimes, the coating pattern of the core wrap sheet disposed on the side facing the skin side is preferably a pattern coating such as spiral, stripe, or dot so as not to impair the absorption performance. Various types of adhesives that have been used in the manufacture of absorbent articles such as disposable diapers can be used without particular limitation.

The horizontal position (horizontal center position) of the polymer inlet 31 is preferably a position where the separation distance W1 (see FIG. 4) from the side surface 34 of the duct 30 is 0 to 25% of the total width W of the upper surface 32. A position of 0 to 15% is more preferable.
The vertical position of the polymer inlet 31 (vertical center position) is such that the separation distance T1 (see FIG. 3) from the upper surface 32 of the duct 30 is the height of the side surface 34 at the same position in the longitudinal direction of the duct 30. The position which becomes 10 to 40% of T is preferable, and the position which becomes 15 to 35% is more preferable.
Further, the positions of the left and right polymer introduction ports 31 may be shifted in the longitudinal direction of the duct 30, but are preferably substantially the same position in the longitudinal direction of the duct 30 as shown in FIG. 5.

In the absorbent body manufacturing apparatus 10, as shown in FIGS. 1, 2, and 5, each side surface 34 of the duct 30 has a substantially triangular pyramid shape at a position closer to the rotating drum 20 than the polymer inlet 31. Members 41 and 42 are fixed. Further, a triangular prism-shaped member 43 is provided on the lower surface 33 of the duct 30 at a position closer to the rotating drum 20 than the polymer inlet 31. When the members 41 and 42 are not provided, they are easily separated into layers due to the difference in weight of pulp and polymer. The members 41 and 42 are for agitating the air flow in the drum and improving the wind speed. By providing these, the distribution of the absorbent polymer in the longitudinal direction of the absorber can be made more uniform. The fixing position of the members 41 and 42 is preferably near the center in the height direction on the side surface of the duct 30, and more preferably in the vicinity of the polymer inlet. The shapes of the members 41 and 42 are not particularly limited as long as the air flow can be disturbed, but it is preferable that the protrusion height from the side surface 34 gradually increases as the rotating drum 20 is approached.
In addition, when manufacturing the absorber 1 using the manufacturing apparatus 10 of this absorber, what has air permeability is used as the core wrap sheets 5A and 5B.

Next, a method for producing an absorbent body having a structure in which a core material is coated with a fibrous material and an absorbent polymer deposit using the absorbent body production apparatus 10 described above, that is, production of the absorbent body of the present invention. One embodiment of the method will be described.
In the method of the present embodiment, the absorbent polymer 3 is mixed in the air flow that conveys the fiber material 22, and the fiber material 22 and the absorbent polymer 3 that are in a scattered state are deposited in a predetermined shape, respectively. A step of obtaining an absorbent core of the absorbent body. And the absorptive polymer 3 is introduce | transduced into the air flow which conveys the fiber material 22 from two places spaced apart in the direction Y (refer FIG. 5) orthogonal to the flow direction X (refer FIG. 5) of this air flow.

The manufacturing method of this embodiment will be described in detail below.
In this embodiment, in order to manufacture an absorber using the above-described absorber manufacturing apparatus 10, first, the rotary drum 20 in the manufacturing apparatus 10 is rotated and the intake fan is operated. In addition, the first and second core wrap sheet supply mechanisms and the adhesive coating apparatuses 6A and 6B are operated.
By the operation of the intake fan, a suction force is generated on the bottom surface portion of the accumulation recess 20 located on the space B, and an air flow flowing toward the outer peripheral surface of the rotary drum 20 is generated in the duct 30.

Then, the fiber material 22 is introduced into the duct 30 so that the fiber material 22 is scattered, and the absorbent polymer 3 is introduced into the duct 30 from each of the two polymer introduction ports 31.
As the fiber material, short fibers of cellulose fibers such as pulp fibers, rayon fibers and cotton fibers, short fibers of synthetic fibers such as polyethylene, and the like are used. These fibers may be used alone or in combination of two or more.
From the viewpoint of producing a thin absorber used for absorbent articles and the like, the fiber material is preferably mainly composed of pulp fibers, and the ratio of pulp fibers in the fiber material is 20 to 100% by mass. Preferably, it is 80-100 mass% more preferably.

  As an absorptive polymer, various things conventionally used for the absorber of absorbent articles, such as a disposable diaper and a sanitary napkin, can be especially used without a restriction | limiting, for example, a starch type, a cellulose type, a synthetic polymer type | system | group Can be mentioned. As the absorptive polymer, a superabsorbent polymer having a liquid absorptive holding power of 20 times or more of its own weight and having a gelling property is preferable. For example, starch-acrylic acid (salt) graft copolymer, starch- A saponified product of acrylonitrile copolymer, a crosslinked product of sodium carboxymethyl cellulose, an acrylic acid (salt) polymer, and the like are suitable.

  First, the first core wrap sheet supply mechanism is supplied to the rotating drum 20 by the first core wrap sheet supply mechanism, and then the fiber material and the accumulation material 21 are covered with the inner surface of the sheet 5B. The absorbent polymer is sucked and deposited. And the 2nd core wrap sheet | seat 5A is supplied by the 2nd core wrap sheet | seat supply mechanism on the recessed part 21 for accumulation | stacking after these have accumulated.

  As the first and second core wrap sheets 5A and 5B, tissue paper, liquid-permeable nonwoven fabric, and the like conventionally used in absorbent articles such as disposable diapers can be used without particular limitation. Examples of the nonwoven fabric include spunbond nonwoven fabric, spunbond-meltblown-spunbond nonwoven fabric, spunbond-meltblown-meltblown-spunbond nonwoven fabric, needle punched nonwoven fabric, spunlace nonwoven fabric, and air-through nonwoven fabric. The upper and lower surfaces of the absorbent core 4 can be covered with different types of core wrap sheets.

The accumulation of the fiber material and the absorbent polymer in the accumulation recess 21 is a configuration in which the absorbent polymer is contained in the fiber assembly made of the fiber material, and these are the first and second core wrap sheets 5A, What is intermittently arranged between 5B is the continuum 1A of the absorber. The fibrous material and the absorbent polymer deposit are conveyed to the deposit discharge section E and are pulled in a direction away from the rotary drum 20 while being sandwiched between the first and second core wrap sheets 5A and 5B. The mold is released from the recess 21.
The absorbent continuum 1A away from the outer peripheral surface of the rotating drum 20 is conveyed by an arbitrary conveying means such as a belt conveyor, and is cut at a portion where there is no deposit of fiber material and absorbent polymer in a subsequent process. It becomes an individual absorber.

  The absorbent body obtained by the manufacturing method of the present embodiment has a configuration in which the absorbent core 4 made of a deposit (stacked product) of the fiber material 22 and the absorbent polymer 3 is covered with the core wrap sheets 5A and 5B. is doing. The upper and lower surfaces of the absorbent core 4 are fixed to the core wrap sheets 5A and 5B via the adhesive (not shown) applied by the above-described adhesive application devices 6A and 6B.

  According to the manufacturing method of the present embodiment, the absorbent polymer 3 is introduced into the air flow carrying the fiber material 22 from two locations separated in the direction Y perpendicular to the flow direction X of the air flow, According to the manufacturing apparatus of the present embodiment, the polymer introduction ports for introducing the absorbent polymer into the duct are formed at two places on both sides in the longitudinal direction X of the duct, so that the absorbent polymer 3 can be obtained. It can be favorably dispersed in the planar direction of the absorber 1. Thereby, the absorbent body in which the absorbent polymer is uniformly dispersed in the planar direction of the absorbent core can be efficiently and continuously produced. As shown in FIG. 3, instead of forming the polymer introduction port 31 in the vicinity of the upper surface 32 of each of the pair of side surfaces 34, 34 of the duct 30, as shown in FIG. The polymer inlet 31 may be formed in the vicinity of each of the side surfaces 34, 34.

  Moreover, in this embodiment, the state which supplied the 1st and 2nd core wrap sheet | seat in the state which apply | coated the adhesive agent, and pinched | interposed the deposit (fiber pile) of the fiber material 22 and the absorptive polymer 3 with these Since the absorbent polymer 3 is separated from the rotating drum 20, the absorbent polymer 3 is prevented from moving when being separated from the rotating drum 20, and the dispersibility of the absorbent polymer is further improved. An absorbent body is obtained. Since the first core wrap sheet 5B hardly clogs the bottom surface of the accumulation recess, a layer made of a fiber material in the accumulation recess before the polymer is deposited as in the manufacturing method shown in FIG. There is no need to form. Therefore, the absorber can be further reduced in thickness.

  Further, in the present embodiment, when the absorber continuous body 1 </ b> A is pulled away from the rotary drum 20, the blow from the rotary drum 20 side is not performed. That is, in the conventional manufacturing method, the internal space D of the rotating drum 20 in the absorber discharge portion E is kept at a positive pressure, and the absorber or the absorber is blown away by blowing outward from the rotating drum 20 side. In many cases, the continuous body is discharged from the drum 20, but in this embodiment, such blow from the rotating drum 20 side is not performed. Thereby, it is prevented that the absorptive polymer 3 moves and the absorber which was further excellent in the dispersibility of an absorptive polymer is obtained.

1 and 2 show an example of an absorbent body obtained by the manufacturing method of the embodiment described above, as shown in FIG. Hereinafter, although the absorber 1 is demonstrated easily, of course, the absorber manufactured by this invention is not restrict | limited to what has the same structure as the absorber 1. FIG.
As shown in FIG. 6, the absorber 1 has a rectangular shape in plan view and is formed in a vertically long shape. The absorbent body 1 is preferably used as an absorbent article such as a disposable diaper, a sanitary napkin, an incontinence pad, particularly a disposable diaper, and when incorporated in the absorbent article, the longitudinal direction of the absorbent article It is made to correspond to a longitudinal direction (direction which corresponds with a wearer's front-back direction).

  The absorbent body 1 includes an absorbent core 4 and core wrap sheets 5A and 5B that cover the absorbent core 4. As shown in FIG. 6, the absorbent core 4 has a portion in which the central portion in the longitudinal direction is constricted, and has an hourglass-like plan view shape. The absorbent core 4 has a configuration in which the absorbent polymer 3 is contained in the fiber assembly 2 made of the fiber material 22.

  As shown in FIGS. 6 and 7, in the absorbent body 1, two core wrap sheets 5 </ b> A and 5 </ b> B having different widths are arranged on the upper and lower surfaces of the absorbent core 4, and both side portions of one core wrap sheet 5 </ b> A are disposed. It is folded and joined to the other core wrap sheet 5B side. Thereby, the upper and lower surfaces and both side edges of the absorbent core 4 are covered with the core wrap sheets 5A and 5B. In the present embodiment, core wrap sheets extending from both ends in the longitudinal direction of the absorbent core 4 are joined together, and both ends in the longitudinal direction of the absorbent core 4 are also covered with the core wrap sheets 5A and 5B. .

In the absorbent body 1, the absorbent polymer 3 is uniformly dispersed in the planar direction of the absorbent core 4.
The absorbent polymer 3 is uniformly dispersed in the plane direction means that the absorbent core 4 is divided into a plurality of regions in each of the longitudinal direction and the width direction of the absorbent body, and the absorbent polymer 3 is divided into the divided regions. When the content of the absorbent polymer 3 is measured, the variation in the content of the absorbent polymer 3 is not more than a predetermined value for both the row of the divided region in the longitudinal direction of the absorber and the row of the divided region in the width direction of the absorber. That is.
Whether or not the absorbent polymer is uniformly dispersed in the plane direction can be determined by directly measuring the content of the absorbent polymer, but the physiological saline increases or decreases almost in proportion to the content of the absorbent polymer. It is convenient and preferable to make a determination based on the amount of water retained by centrifugation.

More specifically, as shown in FIG. 8, on the absorbent core 4, the longitudinal center line LL extending in the longitudinal direction of the absorbent core 4 and the longitudinal edge of the absorbent core 4. Assuming a width-direction reference line LT extending in the width direction of the absorbent core 4, a square region having a side of 30 mm having sides parallel to both the lines LL and LT is adjacent to the width-direction reference line LT; The center point of the square area is arranged so as to overlap with the longitudinal center line LL, and the area (the hatched area in the figure) is defined as a reference section P.
And the division of the same shape as the reference | standard division P is arrange | positioned adjacent to each other in the longitudinal direction and the width direction of the absorptive core 4, and these divisions are used as divided regions.

In addition, among the divided regions, those that do not overlap with the absorbent core 4 are excluded from the measurement target.
Then, for each divided region to be measured, excluding the divided region that is not the measurement target, the amount of the physiological saline that is centrifuged is measured, and the standard deviation is calculated. Further, the ratio (column standard deviation / column average) of the standard deviation (column standard deviation) for each column of the divided area to the average value (column average) of the centrifugal retention amount of the physiological saline in the column is calculated.
As described above, the dispersibility in the planar direction of the absorbent polymer is the ratio (column standard deviation / column average) for each of the columns of the divided regions in the longitudinal direction of the absorber and the columns of the divided regions in the width direction of the absorber. Can be evaluated by how much the maximum value of the ratio is. A case where the ratio (column standard deviation / column average) is 0.20 or less is “distributed uniformly in the plane direction”. The ratio (column standard deviation / column average) is preferably 0.15 or less and more preferably 0.13 or less for any column. Further, the standard deviation of all data is preferably 1.5 or less, and more preferably 1.3 or less.

In addition, the measurement of the centrifugal retention amount of physiological saline is performed by the following measurement method.
For each divided region, each divided region is put into a mesh bag made of a material having no water retention (such as nylon), and the following operation is performed for each mesh bag so that the absorbent polymer does not fall off. First, each divided area is weighed (this value is defined as (A)). Next, each divided region is immersed in physiological saline for 30 minutes. Thereafter, each divided region is suspended for 10 minutes and drained by natural fall. Next, draining with a centrifugal dehydrator is performed for 10 minutes at a speed of 800 rpm for each divided region.
And the weight (this value is set to (B)) of each division area after draining is measured.
Then, the amount of water retained in each divided region even after draining is obtained by the calculation of (B)-(A), and the value is used as the centrifugal retained amount of physiological saline.

The basis weight of the fiber assembly ² is preferably 50 to 250 g / m ² from the viewpoint of reducing the thickness of the absorber 1 and holding the absorbent polymer between the fibers to suppress the movement of the polymer. More preferably, it is 100-230 g / m < ² >.
Further, the ratio of the basis weight of the absorbent polymer (SAP) to the basis weight of the fiber assembly 2 (SAP / fiber material) can be, for example, 1.30 or more.
Moreover, the thickness of the absorber 1 is 3.0 mm or less from a viewpoint of suppressing rigidity, for example, improving fit to a body shape when used as an absorbent body of an absorbent article and thereby preventing leakage. It is preferably 1.0 to 2.5 mm, more preferably 1.5 to 2.0 mm.
Moreover, it is preferable that it is 50-90 mass%, and, as for the content rate of the absorptive polymer in an absorptive core, it is more preferable that it is 60-80 mass%.

As mentioned above, although one Embodiment of the absorber of this invention was described, this invention is not restrict | limited to the said embodiment, It can change suitably.
For example, as shown in FIG. 9, the fiber material and the absorbent polymer are deposited on the outer peripheral surface of the rotating drum 20 without supplying the core wrap sheet, and the deposit 40 is released from the rotating drum 20. You may coat | cover with core wrap sheet | seat 5A, 5B. In the absorbent body manufacturing apparatus shown in FIG. 9, in order to prevent or reduce clogging by the polymer at the bottom surface of the concave portion for accumulation, it is arranged on the partition plate 45 in the duct 30 and is used for accumulation before the polymer is deposited. A layer made of the fiber material 22 is formed in the recess. In the absorber manufacturing apparatus shown in FIG. 9, the partition plate 45 can be eliminated.

  Further, the covering form of the absorbent core 4 with the core wrap sheet is two core wrap sheets 5A and 5B that are slightly wider than the width of the absorbent core 4, and each of these two core wrap sheets is used as the absorbent core. Of the two core wrap sheets extending from both side edges of the absorbent core 4 on the side of the absorbent core 4 or the absorbent core 4 The absorbent core 4 is placed in the center in the width direction of a single core wrap sheet having a width of 2 to 3 times the width, and the portions extending from both side edges of the absorbent core 4 are absorbed. The form etc. which return | fold and join to the other surface side of the property core 4 may be sufficient.

Moreover, the planar view shape of the recessed part 21 (absorbent core 4) for accumulation | storage can be made into arbitrary shapes, such as a rectangle. Moreover, you may form the deposit (continuous body of an absorptive core) continuous in the circumferential direction of the rotating drum 20.
Further, the absorbent body produced by the present invention includes a liquid-permeable top sheet, a liquid-impermeable or water-repellent back sheet, and a liquid-retaining absorbent body disposed between both sheets, and comes into contact with the body. Although it is preferably used as an absorbent body of an absorbent article that is used, it can also be used for other purposes.

  In addition, instead of depositing the absorbent polymer into the air flow that conveys the fiber material and mixing the fiber material and the absorbent polymer into the accumulation recess, the fibers are accumulated in the accumulation recess. The material may be deposited and then the absorbent polymer conveyed by the air stream free of fiber material may be deposited on the deposited fiber material.

Examples 1 and 2
The pulp fiber and the superabsorbent polymer are absorbed as described above so that the basis weight of the pulp fiber (same as the basis weight of the fiber aggregate) is 220 g / m ² and the basis weight of the superabsorbent polymer is 290 g / m ^2. It supplied to the duct in the absorber manufacturing apparatus which has the same structure as the body manufacturing apparatus 10. The amount of pulp fibers and superabsorbent polymer per absorber was 8.3 g and 11 g in this order. The polymer inlets are provided on both sides of the upper half of the duct, and more specifically, the polymer inlets provided near the upper surface of each side surface of the duct (T1 / T = 0.275). The superabsorbent polymer was introduced from W1 / W = 0).

Example 3
The basis weight of the pulp fibers (basis weight in the same fiber assembly) is 167 g / m ^2, except that the basis weight of superabsorbent polymer were replaced so that the 265 g / m ^2, in the same manner as in Example 1 absorbs The body was manufactured.

[Comparative Examples 1 and 2]
The basis weight of the pulp fiber (same as the basis weight of the fiber assembly) is 258 g / m ² , the basis weight of the superabsorbent polymer is 258 g / m ^2, and the polymer inlet is in the width direction on the upper surface of the duct An absorbent body was manufactured in the same manner as in Example 1 except that only one member was provided in the center and the above-described members 41 to 43 were not provided.

[Comparative Example 3]
The basis weight of the pulp fiber (same as the basis weight of the fiber assembly) is 220 g / m ² , the basis weight of the superabsorbent polymer is 320 g / m ^2, and the polymer inlet is in the width direction on the upper surface of the duct An absorbent body was manufactured in the same manner as in Example 1 except that only one member was provided in the center and the above-described members 41 to 43 were not provided.

About each absorber obtained by the Example and the comparative example, the reference division and the division following it are set as shown in FIG. 8 by the above-described method, and the physiological saline is centrifugally held for the region included in each division. The amount was measured.
Then, for each column of the divided region in each of the longitudinal direction and the width direction of the absorber, the standard deviation of the centrifugal retention amount and the standard deviation (column standard deviation) for each column of the divided region are centrifuged for the divided region in the column. The ratio (column standard deviation / column average) to the average value (column average) of the retained amount was calculated.
These results are shown in the following [Table 1] to [Table 6].

[Evaluation result by centrifugal retention amount]
From the results shown in the above [Table 1] to [Table 6], in the absorbers of Examples 1 to 3, the maximum values of the ratios (column standard deviation / column average) are both 0.2 or less, It can be seen that the superabsorbent polymer is uniformly dispersed in the planar direction of the absorbent core. On the other hand, in the absorbers of Comparative Examples 1 to 3, the maximum value of the ratio (column standard deviation / column average) was 0.473, 0.778, and 0.385 in this order, and the superabsorbent polymer. It can be seen that the dispersibility in the plane direction is inferior in the dispersibility in the width direction (direction perpendicular to the circumferential direction of the rotating drum).

It is a schematic diagram which shows one Embodiment of the manufacturing apparatus of the absorber of this invention. It is a perspective view which shows the structure of the absorptive polymer inlet vicinity of the duct in the manufacturing apparatus of the absorber shown in FIG. It is a vertical direction sectional view (II-II line sectional view of Drawing 1) showing a section which passes through an absorptive polymer introduction port of a duct in a manufacture device of an absorber shown in Drawing 1. It is sectional drawing (corresponding to FIG. 3) of the duct for explaining a preferable formation position of the absorbent polymer inlet. It is a horizontal sectional view which shows the cross section which passes along the absorptive polymer inlet of the duct in the manufacturing apparatus of the absorber shown in FIG. It is a partially broken top view which shows an example of the absorber obtained by this invention. It is the III-III sectional view taken on the line of the absorber shown in FIG. It is a figure for demonstrating the dispersibility evaluation method of the absorptive core plane direction of an absorptive polymer, and is a top view of the absorptive core which shows the state which set the reference | standard division and the division following it on the absorptive core. . It is a schematic diagram which shows other embodiment of the manufacturing apparatus of the absorber of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Absorber 2 Fiber assembly 21 Fiber material 3 Absorbent polymer 4 Absorbent core 5A, 5B Core wrap sheet 10 Absorber manufacturing apparatus 20 Rotating drum 21 Condensing recess 30 Duct 31 Absorbing polymer inlet 32 Upper surface 33 of duct The lower surface of the duct 34 The side surface of the duct X The flow direction of the air flow conveying the fiber material Y The direction orthogonal to the flow direction

Claims (4)

A method for producing an absorbent body comprising a step of introducing an absorbent polymer into an air flow in a duct and depositing the absorbent polymer in a scattered state in a predetermined shape to obtain an absorbent core,
Introducing the absorbent polymer from two locations that are spaced apart in a direction perpendicular to the flow direction of the air flow and that are lateral to the traveling direction of the absorbent core ;
In the duct, on the downstream side of the two positions where the absorbent polymer is introduced, a substantially triangular pyramidal member is provided with the apex of the triangular pyramid facing the upstream side of the air flow, Manufacturing method of absorber.   The method for producing an absorbent body according to claim 1, wherein the absorbent polymer is introduced into an air stream carrying a fiber material, and the mixed fiber material and the absorbent polymer are deposited in the predetermined shape. Absorber comprising: a rotating drum having a plurality of recesses for accumulation formed at a predetermined interval on the outer peripheral surface; and a duct for supplying the fiber material and the absorbent polymer, which are respectively scattered, to the outer peripheral surface of the rotating drum Manufacturing equipment,
The absorbent polymer, Lupo Rimmer inlet to introduce laterally into said duct with respect to the traveling direction of said integrated recess is formed in the longitudinal direction of both sides two positions of the duct,
In the duct, on the downstream side of the two positions where the absorbent polymer is introduced, a substantially triangular pyramidal member is provided with the apex of the triangular pyramid facing the upstream side of the air flow, Absorber manufacturing equipment.   A first core wrap sheet supply mechanism for supplying a first core wrap sheet on the outer peripheral surface of the rotating drum before the fiber material and the absorbent polymer are deposited in the concave portion for accumulation, and raw materials are deposited in the concave portion for accumulation. A second core wrap sheet supply mechanism for supplying the second core wrap sheet on the outer peripheral surface of the subsequent rotating drum, and the first and second core wrap sheets before being supplied on the outer peripheral surface of the rotating drum, respectively The manufacturing apparatus of the absorber of Claim 3 provided with the two adhesive coating apparatuses which apply an adhesive agent.

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