CN109199701B

CN109199701B - Composite absorption core body with liquid-absorbing self-expanding liquid guide channel and application thereof

Info

Publication number: CN109199701B
Application number: CN201811268962.XA
Authority: CN
Inventors: 荣敏杰; 田云; 许永升; 于庆华; 荣帅帅
Original assignee: Shandong Nuoer Biological Technology Co Ltd
Current assignee: Shandong Nuoer Biological Technology Co Ltd
Priority date: 2016-09-10
Filing date: 2017-09-05
Publication date: 2022-02-01
Anticipated expiration: 2037-09-05
Also published as: CN107397628B; CN109551043B; CN107625583A; CN107625583B; CN109568012A; CN109199701A; CN106361506A; CN109568012B; CN208447937U; WO2018045939A1; CN107397628A; CN109551043A

Abstract

The invention discloses a composite absorption core body, which sequentially comprises a surface layer, a middle layer and a bottom layer from top to bottom, wherein the middle layer comprises a water absorption layer made of a liquid absorption expansibility material which expands after absorbing liquid, and a liquid absorption self-expansion type liquid guide channel is arranged in the water absorption layer. The invention also relates to the use of said composite absorbent core for the manufacture of absorbent articles, in particular diapers. The composite absorption core body has the advantages of good dryness, no lump, no fault and the like, and particularly, the liquid guide channel has the liquid absorption self-expansion characteristic, so that the composite absorption core body or an absorption product comprising the core body also has the advantages of high liquid infiltration and diffusion speed, small back seepage amount and the like.

Description

Composite absorption core body with liquid-absorbing self-expanding liquid guide channel and application thereof

The application is a divisional application of the invention entitled composite absorbent core with liquid-absorbing self-expanding liquid guide channels and application thereof, and the application date of the original application is 2017.09.05, and the application number is 201710790670.1.

Technical Field

The invention relates to the field of composite absorbing cores, in particular to a composite absorbing core with a liquid-absorbing expansion type flow guide channel and application thereof.

Background

In the prior art, a composite absorbent core generally comprises a surface layer, a back layer and an intermediate layer disposed between the surface layer and the back layer, and absorbent material is fixed to the surface of the intermediate layer by means of bonding or the like. When the composite absorption core body is contacted with liquid, the liquid reaches the middle layer through the surface layer, and is absorbed and maintained by the absorbent material fixed on the middle layer, so that the liquid is absorbed. Thus, the amount of liquid that can be absorbed by the absorbent core is determined by the amount of absorbent material and the absorbent properties. In such a structure, the absorbent material is generally distributed between the top layer and the middle layer and between the bottom layer and the middle layer. However, in this structure, the longitudinal penetration rate of the liquid from the surface layer to the back layer and the lateral diffusion rate along the surface of the composite absorbent core are slow, and the solution causes the liquid to be locally accumulated excessively to cause side leakage or flooding.

In order to solve the problem of slow longitudinal permeation speed, CN201310359556.5 discloses a composite absorbent core, which comprises a surface layer, a bottom layer, and a middle absorbent layer arranged between the surface layer and the bottom layer, wherein the middle absorbent layer is provided with a plurality of longitudinal through holes, and the longitudinal through holes are filled with high molecular water-absorbent resin. However, such composite absorbent cores still do not address the slow lateral liquid diffusion rate.

CN201310393117.6 discloses a composite absorption core body with instant absorption function and a paper diaper, wherein the composite absorption core body is composed of a full diversion surface layer, a slow water absorption high polymer layer, a medium-speed water absorption wood pulp cotton mixing layer and a fast water absorption high polymer layer in sequence. However, the fully fluid-permeable surface layer of the composite absorbent core only increases the longitudinal penetration rate of the liquid.

The sanitary articles such as baby diapers are widely used at present, the market share of the diapers comprising the composite core is continuously expanded due to the ultrathin and continuous layer, but the absorbent articles in the prior art, such as the diapers, comprising the composite absorbent core have the following defects: (1) the existing composite absorption core body type baby diaper has low repeated absorption speed and urine leakage phenomenon; (2) after the existing composite absorption core body type paper diaper absorbs urine, the middle absorption layer expands after absorbing urine to enable the composite absorption core body to be hardened due to the fact that the middle absorption layer is composed of multiple layers of dust-free paper and non-woven fabrics.

Disclosure of Invention

Technical problem to be solved

The invention aims to solve the technical problems that the composite absorption core body is low in absorption speed, large in back seepage quantity, hard in expansion after liquid absorption, abrasion to a user caused by expansion and the like.

(II) technical scheme

In order to solve the above technical problems, the present invention provides, in a first aspect, a composite absorbent core having a fluid guiding effect.

The invention also provides in a second aspect the use of the composite absorbent core in the manufacture of an absorbent article.

(III) advantageous effects

Compared with the prior art, the composite absorbing core body adopting the technology of the invention has the following advantages: good drying property, no lump, no fault, no swelling and hardening and less back seepage. Because the liquid guide channel of the liquid absorption self-expansion type is arranged, the liquid guide function is obvious after liquid absorption, the liquid infiltration speed is high, the diffusion performance is also obviously superior to that of a common composite absorption core body, and the liquid guide core can be applied to various absorption products, particularly sanitary products, particularly disposable sanitary products, such as sanitary towels or paper diapers, e.g. ultrathin baby paper diapers, baby paper diapers and the like.

Drawings

Figure 1 is a schematic structural view of one embodiment of the composite absorbent core of the present invention wherein the composite absorbent core is in a pre-liquid-absorbent state and the location of the liquid-directing channels are only obscured from view.

Figure 2 is a cross-sectional view of the composite absorbent core shown in figure 1.

Figure 3 is a schematic structural view of another embodiment of the composite absorbent core of the present invention in which the composite absorbent core is in a pre-liquid-absorbent state but the width of the liquid-directing channels is greater than the width of the composite absorbent core of figure 1.

Fig. 4 shows that the polymeric water-absorbent resin swells to form a very distinct liquid guiding channel after the composite absorbent core of fig. 1 absorbs liquid.

Figure 5 is a cross-sectional view of the composite absorbent core of figure 4.

FIG. 6 is a sectional view of still another embodiment of the composite absorbent core of the present invention, having only one water-absorbent layer formed of a high-molecular water-absorbent resin and no intermediate absorbent layer.

Figure 7 is a schematic view of the composite absorbent core of figure 6 after imbibing liquid.

FIG. 8 is a sectional view of still another embodiment of the composite absorbent core of the present invention, having an upper water-absorbent layer and a lower water-absorbent layer formed of a high-molecular water-absorbent resin, but without an intermediate absorbent layer.

Figure 9 is a schematic view of the composite absorbent core of figure 8 after imbibing liquid.

Fig. 10 to 15 are schematic views of the upper surface of the bottom layer on which one strip-shaped baffle parallel to the length direction of the bottom layer, one strip-shaped baffle perpendicular to the length direction of the bottom layer, a plurality of (3) strip-shaped baffles perpendicular to the length direction of the bottom layer, S-row baffles, Z-baffles and # -shaped baffles, respectively, are placed and hot-melt structural adhesive is sprayed.

In the figure: 1: a surface layer; 2: an upper water-absorbing layer; 3: an intermediate absorbent layer; 4: a lower water absorption layer; 5: a bottom layer; 6: a drainage channel; 7: blank area (area corresponding to the drainage channel without macromolecular absorbent resin)

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

The invention provides a composite absorption core with a diversion effect, which has a five-layer structure and comprises a surface layer, an upper water absorption layer, a middle absorption layer, a lower water absorption layer and a bottom layer from top to bottom; and the upper water absorption layer and/or the lower water absorption layer are/is provided with a liquid guide channel in the middle of the width of the whole composite absorption core body.

The shape and size of the composite absorbent core of the present invention are not particularly limited, and various shapes and desired sizes may be formed as needed. For example, the shape of the composite absorbent core may be, for example, a cylinder, a cube, a rectangular parallelepiped, or designed to have various shapes according to actual needs. For convenience of description, if there is no particular description, a rectangular sheet will be described as an example. The thickness, width and length of the sheet can be designed as desired.

With respect to the top layer and the bottom layer of the composite absorbent core, the top layer is a layer of the composite absorbent core on the liquid-pervious side and the bottom layer is a layer of the composite absorbent core on the opposite side from the top layer, as not indicated to the contrary. Taking the composite absorbent core for the paper diaper as an example, the surface layer is a layer close to the body side, and the bottom layer is a layer far away from the body side.

The invention has no special limit to the whole width of the composite absorption core body, and can be set, cut or spliced according to the requirement. In some embodiments, the composite absorbent core has a width of from 8cm to 15cm, such as from 8cm to 12cm, such as 8, 9, 10, 11, 12, 13 or 14cm, throughout.

The surface layer may be a woven or nonwoven fabric. In some preferred embodiments, the material of the woven or non-woven fabric may be made of fibers selected from the group consisting of polyethylene fibers, polypropylene fibers, polyvinyl chloride fibers, polyester fibers, cellulose fibers, natural fibers or man-made fibers. The nonwoven fabric may be made, for example, by hot air treatment, hot rolling, spunbonding, hydroentangling, or air-laid forming processes of the fibers; the woven fabric can be produced, for example, by weaving using the fibers.

The material of the bottom layer can be a polyethylene film or a polyvinyl chloride film. Preferably, the material of the bottom layer is a gas permeable film, such as a polyethylene gas permeable film or a polyvinyl chloride gas permeable film doped with inorganic particles.

The intermediate absorbent layer may be a woven or nonwoven fabric. In some preferred embodiments, the material of the woven or non-woven fabric may be made of fibers selected from the group consisting of polyethylene fibers, polypropylene fibers, polyvinyl chloride fibers, polyester fibers, cellulose fibers, natural fibers or man-made fibers. The nonwoven fabric may be made, for example, by hot air treatment, hot rolling, spunbonding, hydroentangling, or air-laid forming processes of the fibers; the woven fabric can be produced, for example, by weaving using the fibers.

In other preferred embodiments, the top and/or bottom layers have a grammage of 10g/m²To 90g/m²(e.g., 10, 20, 30, 40, 50, 60, 70, or 80g/m²Or for example 10g/m²To 50g/m²) Preferably 35g/m²To 55g/m²The spun-bonded non-woven fabric or the dust-free paper, or the non-woven fabric or the woven fabric formed by one or more of polyethylene fiber, polypropylene fiber, polyvinyl chloride fiber, polyester fiber, natural or artificial cotton or cellulose fiber through hot air, hot rolling, spunlace, needle punching, spun-bonded or air lapping.

In other embodiments, the intermediate absorbent layer has a grammage of 15g/m²To 80g/m²(e.g., 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, or 75g/m²) The bulky nonwoven fabric of (2) is, for example, a nonwoven fabric having a square gram weight of 35g/m²To 50g/m²The bulky nonwoven fabric of (1). In the case where the intermediate absorbent layer is a bulky nonwoven fabric, the SAP forming the water-absorbing layer may be partially or entirely embedded in the bulky nonwoven fabric before liquid absorption and tightly embedded in the bulky nonwoven fabric after liquid absorption and expansion, so that the shape of the composite absorbent core can be maintained after liquid absorption unlike the composite absorbent core of the prior art in which SAP particles are changed in weight or the like after liquid absorptionAgglomeration and faulting occur. The ability of the composite absorbent core of the present invention to maintain its shape after liquid absorption is particularly advantageous in the case where it is used in a diaper, because if such aggregation or breaking occurs, it causes discomfort to the user and even causes pressure or friction with the body-contacting portion.

In some preferred embodiments, the upper water-Absorbent layer is a Super Absorbent Polymer (SAP) of 20 mesh to 120 mesh (e.g., 20, 40, 60, 80, 100, or 120 mesh); and/or the lower water absorption layer is a polymeric water absorbent resin with 20 meshes to 120 meshes (for example, 20, 40, 60, 80, 100 or 120 meshes).

The high molecular water absorbent resins used in the present application are known, and the SAP used in the water absorbent layer of the present invention is not particularly limited as long as it swells upon absorbing a liquid and forms a liquid guiding channel in a region where the SAP is not distributed. For example, a high molecular water-absorbent resin having various properties is commercially available from Shandong Noll Biotechnology Co., Ltd.

In other preferred embodiments, the upper and/or lower absorbent layers may have a grammage of 80g/m²To 300g/m²(e.g., 80, 100, 150, 200, 250, or 300g/m²). Further, it is preferable that the mesh number distribution (D) of the particles is such that the mesh number of the SAP particles in the upper water-absorbent layer is 50% or more₅₀) In the range of 25 meshes to 50 meshes; the SAP particles in the lower water absorption layer have a particle mesh distribution (D) of 80% or more₈₀) In the range of 30 meshes to 100 meshes. If the particles of the high-molecular water-absorbent resin are too large, the sanitary product may have strong granular feeling and be uncomfortable; if the particles are too small, more dust can be generated in the production process of the sanitary product.

Preferably, the SAP particles may have a particle size ratio (coefficient of linear expansion) after and before liquid absorption of 20 to 100 (e.g., 20, 30, 40, 50, 60, 70, 80, 90, or 100). For example, if the height of the drainage channel corresponds to the sum of the diameters of 5 80-mesh SAP particles (about 0.180mm in particle size and 50 in expansion ratio), the height of the liquid-intake pre-drainage channel is about 0.90mm and the height after liquid intake is about 45mm, which corresponds to a 50-fold improvement in drainage effect. Therefore, the liquid guiding channel of the present invention is a liquid-absorbing self-expanding liquid guiding channel, which is significantly different from the case where the liquid guiding channel is provided between, for example, a water absorbing layer and an intermediate layer without expanding the liquid guiding channel by utilizing the liquid-absorbing expansion characteristic of the absorbing material, because the liquid guiding channel of the latter case has no liquid-absorbing self-expanding capability, and thus either a large-sized liquid guiding channel is originally designed, thereby sacrificing the integrity, the overall strength and the beauty of the composite absorbent core, or a smaller liquid guiding channel is originally provided, thereby resulting in a significant shortage of liquid guiding effect.

In some preferred embodiments, the SAP may have a pressurized absorbency under a pressure of 0.7psi of not less than 10g/g, such as from 10g/g to 26g/g, such as 10, 15, 20, 25 g/g.

In some preferred embodiments, D of the SAP₅₀Is 25 mesh to 50 mesh (i.e. 50% of the particles have a size in the range of 25 mesh to 50 mesh) or any subrange thereof, e.g. 25, 30, 35, 40, 45 or 50 mesh. In some other preferred embodiments, D of the SAP₈₀Is 30 mesh to 100 mesh (i.e. 80% of the particles have a size in the range of 30 mesh to 100 mesh) or any subrange thereof, e.g. 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95 or 100 mesh. SAP particles in the size range may enable the composite absorbent core to better form drainage channels after swelling upon absorption of liquid.

In some preferred embodiments, the whirlpool absorption rate of the SAP may be less than 85 seconds, for example less than 85, 60, 45, 20 seconds. The method for testing the absorption speed of the vortex method comprises the following steps: a100 mL beaker with a rotor was charged with 50.0. + -. 0.5g of 0.9% physiological saline, and the beaker was placed on a constant temperature magnetic stirrer and stirred at 600 rpm, and 2.00g of a polymer was accurately weighed and put in a vortex, and a stopwatch was used to start counting, and when the vortex disappeared and the liquid surface became horizontal, the time (seconds) was recorded as an end point. 3 samples are taken for testing, and the average value of the 3 samples is taken as a determination result and is accurate to one decimal. Wherein the temperature of the normal saline is 25 +/-2 ℃; the beaker is a flat-bottomed beaker; the diameter of the magnetic stirring rod is 8mm, and the length of the magnetic stirring rod is 30 mm.

In some preferred embodiments, the SAP has a 16 hour eluate content of less than 15%, such as less than 14%, 13%, 12%, 11%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, or 1%. The test method for the content of dissolved substances in 16 hours is as follows: 200mL of normal saline is weighed by a measuring cylinder and poured into a 250mL beaker or conical flask; weigh about 1g SAP, place in a conical flask, record the weight m of SAP weighed_s(ii) a Stirring the normal saline containing the SAP for 1 hour at the rotating speed of 250 +/-50 revolutions per minute; stirring the other physiological saline solution containing 200mL of SAP-free physiological saline solution to obtain a blank sample; stopping stirring, completely sinking the gel macromolecule into the cup bottom (standing for 10 minutes), and filtering about 100mL of supernatant; 50mL of the blank and the filtrate of the sample were each measured, titrated with a standard NaOH solution to a pH of 10, titrated with a standard hydrochloric acid solution to a pH of 2.7, and the volume of the standard solution used was recorded. Amount of carboxylic acid species n_COOHAnd (3) calculating: n is_COOH＝(V_NaOH,s–V_NaOH,b)c_NaOH；V_NaOH,sThe volume of standard NaOH solution required to titrate the sample filtrate to pH 10; v_NaOH,bThe volume of standard NaOH solution required to titrate the blank filtrate to pH 10; c. C_NaOHThe quantity concentration of the substance which is NaOH standard solution; the amount of all carboxylate species n_totAnd (3) calculating: n is_tot＝(V_HCl,s– V_HCl,b)c_HCl；V_HCl,sVolume of standard HCl solution used to titrate the sample filtrate from pH 10 to pH 2.7; v_HCl,bVolume of standard HCl solution used to titrate the blank filtrate from pH 10 to pH 2.7; c. C_HClThe quantity concentration of a substance that is an HCl standard solution; the amount of sodium acrylate material was calculated as follows: n is_COONa＝n_tot–n_COOH(ii) a Mass m of acrylic acid and sodium acrylate_COOHAnd m_COONaThe calculation is as follows: m is_COOH＝n_COOH×M_COOH×Fdl；m_COONa＝n_COONa×M_COONa×Fdl；M_COOHIs the molar mass of acrylic acid, equal to 72 g/mol; m_COONaIs the molar mass of sodium acrylate, equal to 94 g/mol; fdl is the dilution index, etc4 at 200/50; soluble content w is expressed as mass fraction: w ═ m_COOH+m_COONa)/m_s ×100；m_sTo test the quality of the SAP samples. Two samples were tested in parallel for averaging.

In some more preferred embodiments, at least 2 classes of SAPs of different indices are used. For example, the SAP of the upper absorbent layer has a absorbency under pressure of greater than 10g/g at 0.7psi and a particle size distribution in the range of 25 mesh to 50 mesh for more than 50% of the particles; the vortex absorption rate of SAP in the lower water absorption layer is less than 85 seconds, the size distribution range of 80% of particles is 30 meshes to 100 meshes, and the 16-hour dissolved-out content of SAP is less than 15%.

In other particularly preferred embodiments, the centrifugal retention capacity of the polymeric water-absorbent resin used in the upper water-absorbent layer is higher than that of the lower water-absorbent layer, and the liquid absorption rate of the polymeric water-absorbent resin used in the upper water-absorbent layer is slower than that of the lower water-absorbent layer. When the upper absorbent layer and the lower absorbent layer adopt the SAP combination, the liquid return seepage amount after liquid absorption can be obviously reduced.

In some embodiments, the upper water-absorbing layer is fixed on the lower side of the surface layer through a hot melt structural adhesive layer; and/or the lower water absorption layer is fixed on the upper side surface of the bottom layer through a hot melt structure adhesive layer.

Regarding the position of the liquid guiding channel, in other embodiments, the upper absorbent layer and the lower absorbent layer are provided with the liquid guiding channel at a position substantially in the middle or in the middle of the width of the entire composite absorbent core. In other embodiments, the upper absorbent layer has wicking channels across the width of the composite absorbent core and the lower absorbent layer has no wicking channels. In some preferred embodiments, the lower absorbent layer has drainage channels in the middle of the width of the entire composite absorbent core, while the upper absorbent layer has no drainage channels.

The number of the liquid guiding channels is not particularly limited in the present invention, and may be, for example, 1 to 4, such as 1, 2, 3, or 4.

The shape of the liquid guide channel is not particularly limited in the present invention, as long as the absorbed liquid can be diffused more rapidly. For example, the shape of the liquid guide channel can be an elongated shape, a Z shape, an S shape or a # -shaped shape. Of course, these regions may have other shapes as long as they allow for rapid liquid diffusion and reduced rewet. In some preferred embodiments, the liquid is preferably in the shape of a long strip or a well from the viewpoint of the lateral diffusion rate of the liquid.

The shape of the inner cavity of the liquid guide channel is not particularly limited, and the cross-sectional shape of the liquid guide channel is, for example, V-shaped, trapezoidal, square, rectangular, semicircular or elliptical.

The width of the liquid guiding channel (i.e. the width of the blank area) of the composite absorbent core is not particularly limited in the present invention. In case the composite absorbent core is used in a diaper, the width of the liquid-conducting channel is preferably 0.5cm to 4cm, for example 0.5, 1, 2, 3 or 4 cm. If the baffle is too narrow, the optimal liquid infiltration speed cannot be obtained; if the baffle is too wide, the macromolecules on the two sides of the diversion layer are too thick, and the liquid absorption area of the water absorption layer is reduced.

In some embodiments, the liquid-conducting channels of the composite absorbent core have a dimension (i.e., height) in the thickness direction of less than 1cm, such as less than 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, or 0.1cm, or even less, before liquid is not absorbed. Thus, such shallow drainage channels are not visible at all in appearance, and even the presence of the drainage channels is not felt without careful pressure to the touch. Conversely, if the height of the drainage channels is set too high with the same amount of SAP, the thickness of the composite absorbent core may be too great, affecting the integrity, overall strength, and appearance of the composite absorbent core.

It will be appreciated that such a height of the drainage channels, while ensuring the integrity, overall strength and appearance of the composite absorbent core, is likely to limit the drainage capacity of the drainage channels if the drainage channels are less than 1cm before and after high wicking, both before and after wicking.

However, the water-absorbent layer (upper water-absorbent layer and/or lower water-absorbent layer) of the composite absorbent core of the present invention is formed using SAP particles having a high degree of swelling after liquid absorption, the liquid-guiding channels of the composite absorbent core are arranged in the water-absorbent layer, and no water-absorbent material such as SAP is distributed in the water-absorbent layer at the respective positions where the liquid-guiding channels are arranged. That is, the liquid guide channel is a region where the SAP is not distributed, and such a region is referred to as a blank region in the present invention for the convenience of description. Because the SAP particles are highly expanded after absorbing liquid, the height of the liquid guide channel (the size of the composite absorbing core body in the thickness direction) after absorbing liquid is remarkably increased, and the liquid guide effect of the liquid guide channel is remarkably improved. In other words, the liquid guide channel of the composite absorption core body has the self-expansion characteristic after imbibing, and is a self-expansion type liquid guide channel. Thereby not only ensuring the integrity, the integral strength and the appearance of the composite absorbing core body before absorbing liquid (such as the product sale stage), but also ensuring that the composite absorbing core body has enough liquid absorbing and flow guiding effects after absorbing liquid.

In some embodiments, the composite absorbent core may omit the upper absorbent layer and/or the middle layer, such that the composite absorbent core may have a three-layer structure, i.e., a top layer, an upper absorbent layer (or a lower absorbent layer), and a bottom layer, respectively, from top to bottom, or a four-layer structure, i.e., (1) a top layer, a middle absorbent layer, a lower absorbent layer, and a bottom layer, respectively, from top to bottom, or (2) a top layer, an upper absorbent layer, a middle absorbent layer, and a bottom layer.

The present invention provides in a second aspect the use of a composite absorbent core according to the first aspect of the invention in the manufacture of an absorbent article. In some preferred embodiments, the absorbent article is a disposable sanitary article comprising the composite absorbent core, in further preferred embodiments the disposable sanitary article is a sanitary napkin or a diaper, in particular an infant diaper.

Taking the case that the absorbent article is a diaper as an example, the diaper can adopt the structure of the prior art except the composite absorbent core. For example, the diaper may include an innermost layer and an outermost layer sandwiching the composite absorbent core, an elastic waist band having hook and loop fasteners at both ends, three-dimensional containment flaps at both sides, and a front waist panel capable of being used in cooperation with the hook and loop fasteners.

In some more preferred embodiments, the composite absorbent core is used for diapers, and the liquid guide channel is elongated, more preferably elongated perpendicular to the length and/or width of the sheet of absorbent core, so that after the SAP absorbs urine and expands, the liquid guide channel is elongated perpendicular to the length and/or width of the sheet, and the sheet can be bent or folded back and forth and/or right and left along the formed liquid guide channel. In the case where the liquid guiding passage is bent left and right with respect to the body along the width perpendicular to the sheet, the pressing or rubbing of the inner sides of the legs due to the expansion after the composite absorbent core absorbs urine can be reduced, thereby eliminating or reducing the discomfort caused by the expansion of the absorbent core; in the case of a back and forth bend along a drainage channel perpendicular to the length of the sheet, discomfort or unsightly appearance due to significant back and forth bulging caused by expansion of the composite absorbent core may be reduced. In some more preferred embodiments, the liquid guide channel is elongated, and the composite absorbent core after liquid absorption can be freely bent left and right to form an angle of not more than 60 °.

The invention will be further explained below with reference to the drawings.

Referring to fig. 1, a composite absorbent core with a flow guiding effect according to the present invention is shown, wherein the composite absorbent core has a five-layer structure, which is a surface layer 1, an upper water-absorbing layer 2, a middle water-absorbing layer 3, a lower water-absorbing layer 4 and a bottom layer 5 from top to bottom. And the lower water absorption layer 4 is provided with a liquid guide channel 6 in the middle of the width of the whole composite absorption core body.

The overall width of the composite absorbent core is 8-15cm, for example 8-12 cm. The lower water absorption layer 4 is provided with a liquid guide channel 6 with a width of 0.5-4cm, for example, in the middle of the width of the whole composite absorption core body. The width of the drainage channel can be designed according to the needs, and can be relatively smaller (as shown in fig. 2) or slightly larger (as shown in fig. 3).

FIG. 2 is a cross-sectional view of the composite absorbent core shown in FIG. 1; FIG. 3 is a schematic structural view of another embodiment of the composite absorbent core of the present invention, wherein the composite absorbent core is in a pre-liquid-absorbent state, but the width of the liquid-directing channels is greater than the width of the composite absorbent core of FIG. 1; FIG. 4 is a schematic view showing the absorbent core of FIG. 1 imbibed with a polymeric water-absorbent resin and then swollen to form a very distinct drainage channel; figure 5 is a cross-sectional view of the composite absorbent core of figure 4.

Referring to fig. 2, fig. 2 is a cross-sectional view of the composite absorbent core shown in fig. 1. As can be seen from fig. 2, before water absorption and expansion, the cross-sectional area of the composite absorbent core at the liquid guide channel 6 is small, the difference between the thickness of the composite absorbent core at the position of the liquid guide channel 6 and the thickness of the composite absorbent core at the adjacent position (see fig. 1 to 3) is small, and the difference is in millimeter level, which is equivalent to the sum of the diameters of a plurality of or tens of high molecular water absorbent resin particles before expansion, and the packaging and the appearance of the composite absorbent core or the absorbent article comprising the composite absorbent core are not affected. When the water absorbing layer made of the high molecular resin absorbs water and swells, the high molecular water absorbing resin is not distributed at the position of the liquid guiding channel, and the high molecular water absorbing resin beside the liquid guiding channel absorbs water and swells, so that the liquid guiding channel with the channel cross section area being remarkably increased and the remarkable flow guiding effect is achieved is formed (refer to fig. 4 and fig. 5).

FIG. 6 is a sectional view of still another embodiment of the composite absorbent core of the present invention, having only one water-absorbent layer formed of a high-molecular water-absorbent resin and no intermediate absorbent layer. Such a composite absorbent core is also capable of forming wicking channels of large cross-sectional area (as shown in figure 7) upon imbibing liquid.

FIG. 8 is a sectional view of still another embodiment of the composite absorbent core of the present invention, having an upper water-absorbent layer and a lower water-absorbent layer formed of a high-molecular water-absorbent resin, but without an intermediate absorbent layer. Such a composite absorbent core is also capable of forming wicking channels of large cross-sectional area (as shown in figure 9) upon imbibing liquid.

The method of making the composite absorbent core of the present invention may, for example, comprise the steps of:

(1) a baffle is arranged at the middle position of the width of the bottom layer on the upper side surface of the bottom layer along the length of the bottom layer, and then a hot-melt structural adhesive layer is sprayed by a glue sprayer;

(2) spraying a liquid-absorbing expansion material for forming a lower water-absorbing layer on the upper side surface of the bottom layer sprayed with the hot-melt structural adhesive, and laying a middle absorbing layer on the upper part of the lower water-absorbing layer;

(3) spraying a hot-melt adhesive layer on the lower side surface of the surface layer by using a glue sprayer and spraying a liquid-absorbing expandable material for forming an upper water-absorbing layer;

(4) covering the material obtained in the step (3) on the middle absorption layer of the material obtained in the step (2) in a mode that the upper absorption layer side faces downwards;

(5) and taking out the baffle and compacting to obtain the composite absorption core body.

In other embodiments, the method of making a composite absorbent core according to the first aspect of the present invention may also comprise the steps of:

(1) spraying a first hot-melt structure adhesive layer on the lower side surface of the surface layer by using a glue sprayer;

(2) placing a first baffle on the upper side of the middle absorbing layer at the middle position of the width of the middle absorbing layer along the length of the middle absorbing layer, and then spraying a first liquid-absorbing expansion material for forming an upper water-absorbing layer;

(3) bonding a first hot-melt structure adhesive layer on the upper side surface of the middle absorption layer, on which the first liquid-absorbing expansion material is sprayed, taking out the first baffle and compacting;

(4) spraying a second hot-melt structure adhesive layer on the upper side surface of the bottom layer by using a glue sprayer;

(5) placing a second baffle on the lower side of the intermediate absorbent layer at a location intermediate the width of the intermediate absorbent layer along the length thereof and then spraying a second liquid absorbent intumescent material for forming a lower absorbent layer;

(6) and bonding the second hot-melt structure adhesive layer on the lower side surface of the middle absorption layer, which is sprayed with the second liquid absorption expansible material, taking out the second baffle and compacting.

The method is not necessarily performed in the above order. For example:

the step (1) and the step (2) can be carried out simultaneously, sequentially or in reverse order;

the step (4) and the step (5) can be carried out simultaneously, sequentially or in reverse order;

the step (1) and the step (4) can be carried out simultaneously, sequentially or in reverse order;

step (2) and step (5) may be performed sequentially or in reverse order;

the step (1) and the step (5) can be carried out simultaneously, sequentially or in reverse order;

the step (2) and the step (4) can be carried out simultaneously, sequentially or in reverse order;

provided that step (3) must be performed after steps (1) and (2), and step (6) must be performed after steps (4) and (5).

The first liquid-absorbent swellable material forming the upper water-absorbent layer and/or the second liquid-absorbent swellable material forming the lower water-absorbent layer may be fed by at least one feeding roller.

In addition, a third baffle plate can be placed in a region corresponding to the preset position of the liquid guide channel before the first hot-melt structure adhesive layer is sprayed on the lower side surface of the surface layer, and/or a fourth baffle plate can be placed in a region corresponding to the preset position of the liquid guide channel before the second hot-melt structure adhesive layer is sprayed on the upper side surface of the bottom layer, so that a corresponding hot-melt structure adhesive non-spraying region is formed, and the hot-melt structure adhesive non-spraying region is aligned with the first baffle plate and/or the second baffle plate and then bonded.

The shape of the baffle should correspond to the shape and size of the liquid conducting channel. For example, the liquid guide channel is an elongated liquid guide channel with a width of 1 to 4cm, and the baffle plate should be an elongated baffle plate capable of forming a liquid guide channel with a width of 1 to 4 cm.

The present invention will be further described below by way of examples, but the scope of the present invention is not limited to the examples.

Example 1

The surface layer has a width of 9cm and a gram weight of 10g/m²The upper water absorption layer of the dust-free paper adopts the gram weight of 140g/m²20 mesh high molecular water-absorbing resin, the middle absorbing layer adopts the gram weight of 35g/m²The lower water absorption layer adopts a gram weight of 140g/m²40 mesh high molecular water-absorbing resin, the bottom layer is 9cm wide and 10g/m gram weight²The dust-free paper of (1); the preparation steps are as follows:

1) placing a strip baffle plate with the width of 1cm at the upper side of the bottom layer and the middle part of the bottom layer along the length of the baffle plate, and spraying 0.5g/m by using a glue sprayer²The hot-melting structure adhesive layer;

2) spraying a lower water absorption layer on the upper side surface of the bottom layer of the hot-melt adhesive layer, and laying a middle absorption layer on the upper part of the lower water absorption layer;

3) spraying a hot-melt adhesive layer on the lower side surface of the surface layer by using a glue sprayer and spraying an upper water absorbing layer;

4) and (3) covering the upper part of the middle absorbing layer in the step 2) with the side surface of the upper water absorbing layer in the step 3) downward, and taking out the strip baffle plate and compacting to obtain the composite absorbing core body with the flow guiding effect.

Example 2

The surface layer has a width of 10cm and a gram weight of 30g/m²The upper water absorption layer of the dust-free paper adopts the gram weight of 140g/m²25 mesh macromolecular water-absorbing resin, the gram weight of the middle absorbing layer is 45g/m²The lower water absorption layer adopts a gram weight of 140g/m²80 mesh high molecular water-absorbing resin, the bottom layer is 10cm wide and 30g/m gram weight²The dust-free paper of (1); the preparation steps are as follows:

1) placing a strip baffle plate with a width of 2.5cm at the upper side of the bottom layer and the middle part of the bottom layer along the length thereof, and spraying 1g/m with a glue sprayer²The hot-melting structure adhesive layer;

Example 3

The surface layer has a width of 11cm and a gram weight of 50g/m²The upper water absorption layer of the dust-free paper adopts the gram weight of 140g/m²32 mesh macromolecular water-absorbing resin, the middle absorbing layer adopts the gram weight of 50g/m²The lower water absorption layer adopts a gram weight of 140g/m²The bottom layer is made of polymer water-absorbing resin with the size of 11cm and the gram weight of 50g/m²The dust-free paper of (1); the preparation steps are as follows:

1) placing a 4cm wide strip baffle at the upper side of the bottom layer and the middle part of the bottom layer along the length thereof, and spraying 1.5g/m with a glue sprayer²The hot-melting structure adhesive layer;

Example 4

The surface layer has a width of 12cm and a gram weight of 20g/m²The upper water absorption layer of the dust-free paper adopts the gram weight of 140g/m²34 mesh high molecular water-absorbing resin, the middle absorbing layer adopts the gram weight of 38g/m²The lower water absorption layer adopts a gram weight of 140g/m²120 mesh macromolecular water-absorbing resin, the bottom layer adopts a width of 12cm and a gram weight of 20g/m²The dust-free paper of (1); the preparation steps are as follows:

1) a Z-shaped baffle plate with the width of 3cm is arranged at the middle part of the width of the bottom layer on the upper side of the bottom layer, and then 1.8g/m is sprayed and coated by a glue sprayer²The hot-melting structure adhesive layer;

Example 5

The surface layer has a width of 8cm and a gram weight of 30g/m²The upper water absorption layer of the dust-free paper adopts the gram weight of 110g/m²33 mesh macromolecular water-absorbing resin, the gram weight of the middle absorbing layer is 38g/m²The lower water absorption layer adopts a gram weight of 140g/m²108 mesh macromolecular water-absorbing resin, the bottom layer adopts a width of 12cm and a gram weight of 20g/m²The dust-free paper of (1); the preparation steps are as follows:

1) placing a 2cm wide S-shaped baffle at the middle part of the upper side of the bottom layer and the width of the bottom layer, and spraying 1.6g/m with a glue sprayer²The hot-melting structure adhesive layer;

In the above embodiment, the elongated baffles are positioned so that the lower absorbent layer is not spilled in the area where the void is left in the middle of the upper portion of the bottom layer. When the absorbent core absorbs liquid, the high molecular water-absorbent resin constituting the upper absorbent layer and the absorbent layer swells to form the liquid-conducting channel 6 at a position where the lower absorbent layer is not sprinkled down, whereby the liquid leakage time can be shortened and the diffusion length of the composite absorbent core can be improved well.

Comparative example 1

A composite absorbent core (i.e., a normal core) was prepared in substantially the same manner as in example 1, except that the liquid-conductive channels (i.e., grooves) were not formed.

The composite absorbent cores of the present invention were tested by cutting the cores prepared in examples 1 and 2 above to a 38X 10cm gauge and using comparative example 1 as a control.

The test method is that a stainless steel circular ring (with the inner diameter of 50 mm, the outer diameter of 60mm, the weight of 320g and the cylinder height of 5cm) is arranged in the middle of the composite absorption core body, 80ml of normal saline is added each time, and liquid is added for three times at intervals of 10 minutes; return permeability was measured at 30 minutes (10 cm diameter pressure weight, 12kg weight, neutral medium speed filter paper). See table 1 below for results.

TABLE 1

From the above data, it can be seen that the composite absorbent core of the present invention with drainage channels has significant advantages in terms of absorption rate and rewet.

Example 6

A composite absorbent core was prepared in substantially the same manner as in example 1, except that: forming a liquid guide channel with the width of 3.5 cm; the gram weight of the surface layer is 40g/m²The upper water absorption layer of the dust-free paper adopts the gram weight of 140g/m²A water-absorbent resin having a particle size of 20 to 50 mesh; the lower water absorption layer adopts the gram weight of 140g/m²The macromolecular water-absorbing resin with the particle size of 20 meshes to 50 meshes; the gram weight of the bottom layer is 40g/m²The dust-free paper of (1); step 1) in the spraying machine, 1.5g/m of spraying²The hot melt structure glue layer. Comparative example 2

A composite absorbent core (i.e., a normal core) was prepared in substantially the same manner as in example 6, except that the liquid-conductive channels (i.e., grooves) were not formed.

The composite absorbent cores obtained in example 6 and comparative example 2 were measured for liquid absorption, diffusion and rewet properties. The measurement was carried out by 4 times of liquid addition. The specific operation is as follows.

The 1 st liquid adding is started to time, the time is recorded as 0, the liquid adding amount is 60mL of physiological saline each time, the temperature is 23 +/-2 ℃, the liquid diffusion length is measured in 4 th minute, and the measurement is carried out by a graduated scale. The 2 nd addition was made at 5 minutes, the 2 nd diffusion length measurement was made at 9 minutes, and the first rewet measurement was made at 10 minutes. The 3 rd addition was made at 12 th minute, the 3 rd diffusion length measurement was made at 21 th minute, and the 2 nd rewet measurement was made at 22 th minute. The 4 th addition was made at 24 minutes, the 4 th diffusion length measurement was made at 33 minutes, and the 3 rd rewet measurement was made at 34 minutes. The liquid adding method is to add liquid by using a liquid adding device which is provided with a vertical liquid adding pipe with the inner diameter of 2.4 cm, the lower part of the liquid adding pipe is a flat plate, weights are respectively pressed on two sides of the flat plate, each weight weighs 0.6kg, the total weight of the liquid adding device and the weight is 2kg, the absorption speed is the infiltration time, namely the time for liquid to completely infiltrate after liquid is added, the test method of the rewet is to press filter paper on the surface of the paper diaper after liquid absorption by using 1.25kg weight, the pressing is carried out for 1 minute, and the mass difference of the filter paper before and after the weight is weighed is the rewet amount. See table 2 below for results.

TABLE 2

Note: timing each time point with the test start of 0 min; the absorption time is the time(s) required for complete absorption; the diffusion distance is the distance (cm) of liquid diffusion at the time point of the test; the amount of rewet is the amount of rewet (g) at the test time point.

Examples 7 and 8

Examples 7 and 8 were conducted in the same manner as in example 6, except that the upper and lower water-absorbent layers were formed using SAP particles having a pressure absorption capacity of 10 and 20, respectively.

Examples 9 and 10

Examples 9 and 10 were conducted in the same manner as in example 6, except that the upper and lower water-absorbent layers were formed using SAP particles having vortex absorption rates of 85 and 60, respectively.

Examples 11 and 12

Examples 11 and 12 were carried out in the same manner as in example 6, except that the upper and lower water-absorbent layers were formed using SAP particles having an eluted content of 15% and 10%, respectively.

Examples 13 to 16

Examples 15 to 16 except that the number of particles (D) was used₅₀) The procedure of example 6 was followed except that the SAP particles of 20 and 120, respectively, formed the upper and lower absorbent layers.

Examples 17 to 20

Examples 17 to 20 were conducted in the same manner as in example 6, except that the upper and lower water-absorbent layers were formed using SAP particles having swelling rates of 10, 20, 100 and 150, respectively.

The absorption rate (i.e., the time(s) required for complete infiltration) at 24min, the diffusion length (cm) at 33min and the amount of rewet (g) at 34min of the composite absorbent cores obtained in examples 17 to 20 and comparative example 1 were measured in the same manner as described in example 6, and the percentage reduction in time required for complete infiltration (%), the percentage increase in diffusion length (%) and the percentage reduction in rewet (%) of the core of each example were calculated with respect to the core of comparative example 1. The absorption under pressure was 0.7 psi. See table 3 below for results.

TABLE 3

The absorption rate (time(s) required for complete infiltration) at 24min, the diffusion length (cm) at 33min and the amount of rewet (g) at 34min of the cores obtained in each example and comparative example 2 were measured in the same manner as described in example 6, and the percentage reduction in time required for complete infiltration (%), the percentage increase in diffusion length (%) and the percentage reduction in rewet (%) of the cores of each example with respect to the core of comparative example 2 were calculated. In addition, the pressurized absorption shown in the table represents the pressurized absorption at a pressure of 0.7 psi; the overrun is the ratio of the particle diameter of the SAP particles after saturation absorption of physiological saline to the particle diameter before absorption. The extract content represents the 16 hour extract content. The detection method is as described above.

As can be seen from the above table, the composite absorbent core prepared by the preferred embodiment of the present invention significantly increases the liquid infiltration rate, which can be increased by 50% to 90%; meanwhile, the diffusion length of the liquid can be increased by about 10 to 30 percent; in addition, the back seepage amount can be reduced by about 10 to 80 percent.

Examples 21 to 23

A composite absorbent core was prepared in substantially the same manner as in example 6 except that the contents shown in tables 4 and 5 below, and then a diaper comprising an innermost layer and an outermost layer sandwiching the composite absorbent core, an elastic waist band having hook and loop fasteners at both ends, three-dimensional containment flaps at both sides, and a front waist panel capable of cooperating with the hook and loop fasteners was produced. Among these, three types of SAP were used, which were obtained from shandonoul biotechnology limited, and their relevant properties are shown in table 5 below. The absorption rate of SAP can be expressed in terms of the liquid level at rest or the rotor at rest time, the shorter the time, the faster the absorption rate. As shown in Table 5, the absorption rate was the slowest for 511 type SAP, the fastest for 610S type SAP and centered for 610 type SAP. In addition, the centrifuge retention capacity of 511-type SAP is relatively high, higher than that of 610S-type and 610-type SAP, which are the same. The diapers were tested for absorbency, diffusion and rewet properties as described in example 6 and the results are given in Table 6 below.

TABLE 4

TABLE 5

SAP type	Absorption Rate-liquid surface stationary(s)	Absorption speed-rotor stationary(s)	Centrifugal water retention
				NR511	32	62	34
NR610	24	46	30
				NR610S	20	34	30

TABLE 6

Comparing examples 21 and 22, it can be seen that, also in examples 21 and 22, in which 511 type SAP was used for the upper absorbent layer and 610S type SAP was used for the lower absorbent layer, the composite absorbent core produced in example 22 with liquid-conducting channels exhibited a faster liquid acquisition rate (absorption time (seconds (S)), meaning that the shorter the time, the faster the acquisition rate), a longer diffusion length, and a lower rewet.

As can be seen from comparison of examples 22 and 23, in the case where the liquid-guiding passage is provided, when the absorption speed of the SAP of the upper water-absorbent layer is slower than that of the SAP of the lower water-absorbent layer and the centrifuge retention capacity of the SAP of the upper water-absorbent layer is higher than that of the SAP of the lower water-absorbent layer, the diaper finished product made using such a composite absorbent core has low reverse osmosis amount and good dryness (as shown by the data of example 22); if the 610-type SAP, which has the same absorption rate and the same centrifuge retention capacity, is used for both the upper and lower absorbent layers, the amount of rewet will be relatively high, although the absorption rate of the SAP in the upper absorbent layer is faster than that of the SAP used in example 22.

The composite absorption core prepared by the method of the invention has the following advantages: the dry and cool property is good, no lump is generated, no fault is generated, the liquid infiltration speed is high due to the diversion effect, and the diffusion performance is better than that of a common composite absorption core body. Can be applied to various absorbent products, such as sanitary products, for example, sanitary napkins, even diapers, in particular ultrathin baby diapers, baby diapers and the like.

Claims

1. A composite absorption core body comprises a surface layer, a middle layer and a bottom layer from top to bottom in sequence, and is characterized in that the middle layer comprises a water absorption layer made of a liquid absorption expansibility material which expands after absorbing liquid, and a liquid absorption self-expansion type liquid guide channel is arranged in the water absorption layer; the imbibition self-expansion type drainage channel realizes the self-expansion of the drainage channel by utilizing the imbibition expansion of the imbibition expandable material; the liquid guide channel is formed by not distributing liquid absorption expansion materials in the area of the water absorption layer corresponding to the liquid guide channel; the middle layer comprises an upper water absorption layer positioned on the lower surface of the surface layer and a lower water absorption layer positioned on the upper surface of the bottom layer; the centrifugal water retention capacity of the high-molecular water-absorbent resin used in the upper water-absorbing layer is higher than that of the lower water-absorbing layer.

2. The composite absorbent core of claim 1, wherein:

the liquid guide channel is arranged in the middle of the width of the whole composite absorption core body in the upper water absorption layer and/or the lower water absorption layer; and/or

The upper water absorption layer is fixed on the lower side surface of the surface layer through a hot melt structure adhesive layer; and/or the lower water absorption layer is fixed on the upper side surface of the bottom layer through a hot melt structure adhesive layer.

3. The composite absorbent core of claim 2 wherein said intermediate layer further comprises an intermediate absorbent layer positioned between said upper absorbent layer and said lower absorbent layer.

4. The composite absorbent core according to claim 2, wherein said liquid-conducting channel is provided in said lower absorbent layer at a position in the middle of the width of the entire composite absorbent core.

5. The composite absorbent core according to any one of claims 1 to 4, characterized in that:

the whole width of the composite absorption core body is 8-15 cm; and/or

The width of the liquid guide channel is 0.5-4 cm.

6. The composite absorbent core of claim 5 wherein said composite absorbent core has an overall width of from 8cm to 12 cm.

7. The composite absorbent core of claim 3, wherein:

the surface layer and/or the bottom layer are/is spun-bonded non-woven fabric or dust-free paper with the square gram weight of 10-90g or non-woven fabric or woven fabric formed by hot air, hot rolling, spunlace, needle punching, spun bonding or air lapping and forming one or more of polyethylene fiber, polypropylene fiber, polyvinyl chloride fiber, polyester fiber, natural or artificial cotton or cellulose fiber; and/or

The middle absorbing layer is a fluffy non-woven fabric with the square gram weight of 15-80g, and the liquid absorption swelling material forming the water absorption layer is partially or completely embedded in the fluffy non-woven fabric before liquid absorption.

8. The composite absorbent core of claim 7, wherein:

the surface layer and/or the bottom layer are/is 10g to 50g of spun-bonded non-woven fabric or dust-free paper or non-woven fabric or woven fabric formed by one or more of polyethylene fiber, polypropylene fiber, polyvinyl chloride fiber, polyester fiber, natural or artificial cotton or cellulose fiber through hot air, hot rolling, spunlace, needle punching, spun bonding or air lapping.

9. The composite absorbent core of claim 8, wherein:

the surface layer and/or the bottom layer are/is 35g to 55g of spun-bonded non-woven fabric or dust-free paper or non-woven fabric or woven fabric formed by one or more of polyethylene fiber, polypropylene fiber, polyvinyl chloride fiber, polyester fiber, natural or artificial cotton or cellulose fiber through hot air, hot rolling, spunlace, needle punching, spun bonding or air lapping.

10. The composite absorbent core of claim 7 wherein said intermediate absorbent layer is a lofty nonwoven having a square grammage of 35-50 grams.

11. The composite absorbent core according to claim 7, wherein the liquid-absorbent swelling material forming the water-absorbent layer is partially or completely embedded in said bulky nonwoven before liquid absorption.

12. The composite absorbent core according to any one of claims 1 to 4, wherein said liquid-absorbent swellable material is a polymeric water-absorbent resin.

13. The composite absorbent core according to claim 12, wherein said liquid-absorbent swellable material is a polymeric water-absorbent resin particle.

14. The composite absorbent core according to any one of claims 2 to 4, wherein said upper water-absorbent layer is a 20-120 mesh high-molecular water-absorbent resin, and/or said lower water-absorbent layer is a 20-120 mesh high-molecular water-absorbent resin.

15. The composite absorbent core according to any one of claims 2 to 4, wherein D of the water-absorbent polymer particles of the upper water-absorbent layer₅₀D of 25-50 mesh, and/or the water-absorbent polymer particles of the lower water-absorbent layer₈₀Is 30-100 meshes.

16. The composite absorbent core according to any one of claims 2 to 4, wherein the liquid absorption rate of the polymeric water absorbent resin used in the upper water absorbent layer is slower than that of the lower water absorbent layer.

17. The composite absorbent core according to any one of claims 2 to 4, wherein the polymeric water absorbent resin particles of said upper water absorbent layer have a pressurized absorption capacity of more than 10g/g under a pressure of 0.7psi, and 50% or more of the polymeric water absorbent resin particles have a particle size distribution ranging from 25 mesh to 50 mesh; the vortex absorption speed of the high molecular water-absorbent resin particles of the lower water-absorbing layer is less than 85 seconds, the size distribution range of 80 percent of the high molecular water-absorbent resin particles is 30 meshes to 100 meshes, and the content of the SAP dissolved out in 16 hours is less than 15 percent.

18. The composite absorbent core according to any one of claims 1 to 4, characterized in that:

the liquid guide channel is of a strip-shaped, Z-shaped, S-shaped or groined structure; and/or

The composite absorption core body is a cylinder, a cube or a cuboid.

19. The composite absorbent core according to any of claims 1 to 4, wherein the cross-sectional shape of the liquid-conducting channel is V-shaped, trapezoidal, square, rectangular, semicircular or elliptical.

20. The composite absorbent core according to any one of claims 1 to 4, wherein the number of liquid-conducting channels is from 1 to 4.

21. The composite absorbent core according to any one of claims 1 to 4, wherein the dimension of the liquid-conducting channel of the composite absorbent core in the thickness direction is less than 1 cm.

22. The composite absorbent core according to any one of claims 1 to 4, characterized in that:

the liquid-absorptive swelling material has a linear expansion coefficient of 20 to 100;

the liquid-absorptive and expansible material has a pressurized absorption capacity of not less than 10g/g under a pressure of 0.7 psi;

the vortex absorption speed of the liquid-absorbing expandable material is less than 85 seconds; and/or

The liquid absorbent expandable material has a 16 hour dissolution content of less than 15%.

23. The composite absorbent core according to claim 22, wherein said liquid absorbent dilatant material has a pressurized absorbency under a pressure of 0.7psi of from 10g/g to 26 g/g.

24. Use of a composite absorbent core according to any of claims 1 to 23 in the manufacture of an absorbent article.

25. The use of claim 24, wherein the absorbent article is a disposable hygiene article.

26. The use according to claim 24, wherein the absorbent article is a sanitary napkin or a pant diaper.