Wood pulp dry-wet mixed water absorbing paper

Abstract

This utility model relates to the field of disposable hygiene products, and more particularly to a wood pulp wet-dry mixed absorbent paper. It mainly solves the problems of slow liquid absorption rate, insufficient liquid retention capacity, and easy backflow under pressure in existing absorbent papers. The paper includes an absorbent paper body, comprising a bottom material, a top material, and an absorbent material layer disposed between the bottom and top materials. The absorbent material layer includes a first superabsorbent polymer (SAP) granule layer, a second SAP granule layer, and a first wood pulp fiber layer. The first SAP granule layer is laid on the bottom material, the first wood pulp fiber layer is laid on the first SAP granule layer, and the second SAP granule layer is laid on the first wood pulp fiber layer. The average basis weight of both the first and second SAP granule layers is 5 g / m³. 2 ~50g / m 2 The absorbent paper itself has an absorption capacity of not less than 452 g / m² when measured under a pressure of 5.4 kPa.

Description

Technical Field

[0001] This utility model relates to the field of disposable hygiene products, and in particular to a wood pulp wet and dry mixed absorbent paper. Background Technology

[0002] Absorbent paper is a special type of hygiene material, mainly used for water retention in sanitary napkins, diapers, and seedling cultivation of fruits and vegetables. For example, it can be used as the inner absorbent layer of sanitary napkins and other hygiene products. Currently, most domestically produced absorbent layers for sanitary napkins and other hygiene products are made by wrapping fluff pulp and superabsorbent polymer (SAP) in dust-free paper and then processing them through hot pressing or adhesive bonding. The preparation method is as follows: pulp mixing, pulping, loosening, mixing, forming, extrusion dewatering, and drying are processed into single-layer crepe paper, which is then rolled up for later use. At the same time, another processing step is: pulp mixing, pulping, loosening, mixing, forming, extrusion dewatering to form a semi-finished single-layer base paper, and adding SAP particles to the semi-finished single-layer base paper. Then, the aforementioned single-layer crepe paper is unwound and pressed together with it, dried and crepe-set, and then cut to form absorbent paper.

[0003] The aforementioned absorbent paper, when processed using a wet papermaking process, suffers from a decrease in the absorbency of the superabsorbent polymer particles, resulting in slow liquid absorption rate, insufficient liquid retention capacity, and susceptibility to backflow under pressure. Utility Model Content

[0004] Therefore, in view of the above problems, this utility model provides a wood pulp wet and dry mixed absorbent paper, which mainly solves the problems of slow liquid absorption rate, insufficient liquid retention capacity, and easy backflow under pressure in the existing absorbent paper.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A wood pulp wet-dry hybrid absorbent paper includes an absorbent paper body, defined as extending longitudinally along the length direction of the absorbent paper body and transversely along the width direction of the absorbent paper. The absorbent paper includes a bottom material, a top material, and an absorbent material layer disposed between the bottom material and the top material. The absorbent material layer includes a first superabsorbent polymer (SAP) particle layer and a second SAP particle layer, and a first wood pulp fiber layer containing wood pulp fibers. The first SAP particle layer is laid on the bottom material. Cellulose fibers on the upper surface of the bottom material are fixedly connected to a portion of the surface of the SAP particles in the first SAP particle layer. The first wood pulp fiber layer is laid on the first SAP particle layer, and the second SAP particle layer is laid on the first wood pulp fiber layer. The average basis weight of both the first and second SAP particle layers is 5 g / m². 2 ~50g / m2 The absorbent paper body has an absorption capacity of not less than 452 g / m² when measured under a pressure of 5.4 kPa.

[0007] Furthermore, the average basis weight of the first superabsorbent polymer (SAP) granule layer is not less than the average basis weight of the second SAP granule layer.

[0008] Furthermore, the absorbent material layer also includes a third superabsorbent polymer granule layer and a second wood pulp fiber layer, wherein the second wood pulp fiber layer is laid on the second superabsorbent polymer granule layer and the third superabsorbent polymer granule layer is laid on the second wood pulp fiber layer.

[0009] Furthermore, the absorbent material layer has at least one channel along the longitudinal direction that does not contain superabsorbent polymer particles and wood pulp fibers, and the top layer material and the bottom layer material are compositely connected at the channel.

[0010] A wood pulp wet-dry hybrid absorbent paper includes an absorbent paper body, defined as extending longitudinally along the length direction of the absorbent paper body and transversely along the width direction of the absorbent paper. The absorbent paper includes a bottom material, a top material, and an absorbent material layer disposed between the bottom material and the top material. The absorbent material layer includes an absorbent layer containing a mixture of superabsorbent polymer (SAP) particles and wood pulp fibers, a first SAP particle layer and a second SAP particle layer, and a first wood pulp fiber layer. The absorbent layer is laid on the bottom material. Cellulose fibers on the upper surface of the bottom material are fixedly connected to a portion of the surface of the SAP particles in the absorbent layer. The first SAP particle layer is laid on the absorbent layer, the first wood pulp fiber layer is laid on the first SAP particle layer, and the second SAP particle layer is laid on the first wood pulp fiber layer. The average basis weight of both the first and second SAP particle layers is 5 g / m². 2 ~50g / m 2 The absorbent paper body has an absorption capacity of not less than 452 g / m² when measured under a pressure of 5.4 kPa.

[0011] By adopting the aforementioned technical solution, the beneficial effects of this utility model are as follows: This wood pulp wet and dry mixed absorbent paper has a sandwich structure of a first superabsorbent polymer granule layer, a first wood pulp fiber layer, and a second superabsorbent polymer granule layer, forming a gradient water absorption channel. The second superabsorbent polymer granule layer quickly absorbs the liquid, keeping the top layer dry. The first wood pulp fiber layer guides the diffusion of liquid and quickly locks in water through the first superabsorbent polymer granule layer, ensuring the liquid absorption rate and liquid retention capacity. At the same time, by setting the average basis weight of the first superabsorbent polymer granule layer to be equal to the average basis weight of the second superabsorbent polymer granule layer, liquid is preferentially absorbed and the probability of backflow under pressure is reduced. Attached Figure Description

[0012] Figure 1 This is a cross-sectional structural schematic diagram of Embodiment 1 of this utility model;

[0013] Figure 2 This is a schematic diagram of the drying device in Embodiment 1 of this utility model;

[0014] Figure 3 This is a cross-sectional structural schematic diagram of Embodiment 2 of this utility model;

[0015] Figure 4 This is a cross-sectional structural schematic diagram of Embodiment 3 of this utility model;

[0016] Figure 5 This is a cross-sectional structural diagram of Embodiment 4 of this utility model. Detailed Implementation

[0017] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments.

[0018] The embodiment of this utility model is as follows:

[0019] Example 1:

[0020] refer to Figure 1 and Figure 2As shown, a wood pulp wet-dry absorbent paper includes an absorbent paper body, defined as extending longitudinally along the length direction of the absorbent paper body and transversely along the width direction of the absorbent paper. The absorbent paper includes a bottom material 1, a top material 2, and an absorbent material layer disposed between the bottom material 1 and the top material 2. The absorbent material layer includes a first superabsorbent polymer particle layer 3 and a second superabsorbent polymer particle layer 4 containing superabsorbent polymer particles, and a first wood pulp fiber layer 5 containing wood pulp fibers. The first superabsorbent polymer particle layer 3 is laid on the bottom material 1. The cellulose fibers on the upper surface of material 1 are fixedly connected to a portion of the surface of the superabsorbent polymer particles in the first superabsorbent polymer particle layer 3. The first wood pulp fiber layer 5 is laid on the first superabsorbent polymer particle layer 3, and the second superabsorbent polymer particle layer 4 is laid on the first wood pulp fiber layer 5. The cellulose fibers on the lower surface of the top layer material 2 are fixedly connected to a portion of the surface of the superabsorbent polymer particles in the second superabsorbent polymer particle layer 4. The average basis weight of both the first superabsorbent polymer particle layer 3 and the second superabsorbent polymer particle layer 4 is 5 g / m³. 2 ~50g / m 2 The preferred value is 15g / m 2 The average basis weight of the first superabsorbent polymer granule layer 3 is not less than the average basis weight of the second superabsorbent polymer granule layer 4. Preferably, the average basis weight of the first superabsorbent polymer granule layer 3 is equal to the average basis weight of the second superabsorbent polymer granule layer 4. The absorbent paper body has an absorption capacity of not less than 452 g / m² when measured under a pressure of 5.4 kPa.

[0021] Furthermore, the bottom material 1 and the top material 2 are material layers composed of cellulose fibers, such as toilet paper or non-woven fabric.

[0022] The preparation process of the absorbent paper body includes the following steps:

[0023] 1) The bottom material 1 is unwound and conveyed, and superabsorbent polymer particles are applied to the upper surface of the bottom material 1 to form the first superabsorbent polymer particle layer 3.

[0024] 2) The wood pulp is unwound and conveyed, and then crushed. The crushed wood pulp is then applied to the upper surface of the product from step 1 to form the first wood pulp layer 5.

[0025] 3) The product from step 2 is subjected to negative pressure adsorption, and superabsorbent polymer particles are applied to the product from step 2 to form a second superabsorbent polymer particle layer 4.

[0026] 4) Pre-humidify the product from step 3;

[0027] 5) The top layer material 2 is unwound and conveyed, and then laminated onto the upper surface of the product from step 4;

[0028] 6) The product from step 5 is conveyed to the drying device 10, which includes a manufacturing drying cylinder 101 and a conveyor belt 102 disposed around the manufacturing drying cylinder 101. The conveyor belt 102 and the manufacturing drying cylinder 101 form a drying channel 103. The surface of the conveyor belt 102 is humidified by the lower coloring / humidifying device 12. The product from step 5 is then attached to the conveyor belt 102 and conveyed by the conveyor belt 102.

[0029] 7) The products attached to the conveyor belt 102 are humidified again by the upper coloring / humidification device 11;

[0030] 8) The product from step 7 is fed into the drying channel 103 via the conveyor belt 102 for drying.

[0031] 9) Cut the dried products into sections and then roll them up.

[0032] Furthermore, the drying device 10 also includes a drive roller 104, a tension roller mechanism 105, several guide rollers 106, a correction mechanism 107, and a wrinkling scraper 108. The drive roller 104, tension roller mechanism 105, several guide rollers 106, and correction mechanism 107 are respectively arranged on the periphery of the drying cylinder 101. The conveyor belt 102 is wound around the drive roller 104, tension roller mechanism 105, guide rollers 106, and correction mechanism 107. The conveyor belt 102 partially covers the circumferential surface of the drying cylinder 101. The drive roller 104 and tension roller mechanism 105 ensure the stable operation of the conveyor belt 102 in the drying channel 103, preventing the conveyor belt 102 from loosening or slipping, thereby reducing the risk of material jamming or breakage, making the drying process continuous and smooth, and improving production efficiency. At the same time, the tension roller mechanism 105 automatically adjusts the conveyor belt 108. 2. Tension: Adapts to materials with different moisture contents, preventing material deformation or uneven thickness caused by uneven tension, improving product consistency. The correction mechanism 107 monitors and corrects the offset of the conveyor belt 102 in real time, ensuring that the absorbent paper layer is aligned in the drying channel, reducing edge waste or slitting loss. This not only saves raw materials but also reduces the burden on the subsequent slitting device 13, indirectly shortening the production cycle. The optimized arrangement of multiple guide rollers 106 enhances the coverage of the conveyor belt 102 around the drying cylinder 101, improving heat transfer efficiency. At the same time, by uniformly distributing heat, it avoids local overheating or insufficient drying, shortens drying time, and significantly reduces energy consumption. The overall structure enhances the durability and adaptability of the drying device 10, reduces maintenance frequency, supports the rapid processing of high-humidity materials, solves the problem of "high energy consumption" in the background technology, and improves the overall energy efficiency of the equipment.

[0033] In the above-mentioned preparation process of the absorbent paper body, after the bottom material 1, top material 2, first superabsorbent polymer granule layer 3, second superabsorbent polymer granule layer 4 and first wood pulp fiber layer 5 are humidified, the superabsorbent polymer granules expand and adhere to the cellulose fibers on the moistened top material 2 and bottom material 1, and are subsequently dried to form a fixed whole. Thus, the cellulose fibers on the upper surface of the bottom material 1 are fixedly connected to a portion of the surface of the superabsorbent polymer granules in the first superabsorbent polymer granule layer 3, and the cellulose fibers on the lower surface of the top material 2 are fixedly connected to a portion of the surface of the superabsorbent polymer granules in the second superabsorbent polymer granule layer 4.

[0034] Testing method:

[0035] Metal cylinder: internal cross-sectional area 100±0.2cm² 2 Height 50mm, smooth ring surface

[0036] Pressed block: The pressed block weighs 0.4136KG, and its bottom surface is circular.

[0037] Balance: Accuracy 0.001g, measuring range suitable for weighing samples.

[0038] Stopwatch: Readable to an accuracy of 1 second

[0039] Graduated cylinder: 100ml capacity

[0040] absorbent paper

[0041] Sample size: Typically a square sample of (50±0.2)mm × (50±0.2)mm.

[0042] Number of samples: Generally, 5 samples are taken, and the front and back sides are tested once each.

[0043] Test steps:

[0044] A. The test shall be conducted under standard atmospheric pressure and the ambient temperature shall be 25±0.5℃.

[0045] B. Place the sample into a pre-weighed container and record the initial mass;

[0046] C. Place the sample in a container filled with distilled water, keeping the water level in contact with the sample, and soak for 5 minutes.

[0047] D. Place the sample on absorbent paper, place a pressure block on the sample, and keep it for 10 minutes to allow the surface moisture to be absorbed.

[0048] E. Quickly remove the sample, fold it, weigh it, and record the final mass. Water absorption = final mass - initial mass.

[0049] This wood pulp wet-dry absorbent paper features a sandwich structure consisting of a first superabsorbent polymer granule layer 3, a first wood pulp fiber layer 5, and a second superabsorbent polymer granule layer 4. This structure creates a gradient absorption channel, allowing for rapid absorption through the second superabsorbent polymer granule layer 4, keeping the top layer 2 dry. The first wood pulp fiber layer 5 guides liquid diffusion, while the first superabsorbent polymer granule layer 3 quickly locks in the liquid, ensuring both absorption rate and retention capacity. Furthermore, by setting the average basis weight of the first superabsorbent polymer granule layer 3 to be equal to that of the second superabsorbent polymer granule layer 4, liquid is preferentially absorbed, reducing the probability of backflow under pressure.

[0050] Example 2:

[0051] refer to Figure 3 As shown, this second embodiment is a further improvement on the first embodiment. The difference between the second and the first embodiment is that the absorbent material layer further includes a third superabsorbent polymer granule layer 6 and a second wood pulp fiber layer 7. The second wood pulp fiber layer 7 is laid on the second superabsorbent polymer granule layer 4, and the third superabsorbent polymer granule layer 6 is laid on the second wood pulp fiber layer 7.

[0052] Example 3:

[0053] refer to Figure 4 As shown, this embodiment three is a further improvement on the basis of embodiment one. The difference between it and embodiment one is that: the absorbent material layer is provided with at least one channel 8 without superabsorbent polymer particles and wood pulp fibers in the longitudinal direction, preferably two channels. The top material 2 and the bottom material 1 are compositely connected at the channel 8, thereby improving the diffusion efficiency of the absorbent paper body and thus improving the water absorption efficiency.

[0054] Example 4:

[0055] refer to Figure 5As shown, a wood pulp wet-dry mixed absorbent paper includes an absorbent paper body, defined as extending longitudinally along the length direction of the absorbent paper body and transversely along the width direction of the absorbent paper. The absorbent paper includes a bottom material 1, a top material 2, and an absorbent material layer disposed between the bottom material 1 and the top material 2. The absorbent material layer includes an absorbent layer 9 having a mixture of superabsorbent polymer particles and wood pulp fibers, a first superabsorbent polymer particle layer 3 having superabsorbent polymer particles, a second superabsorbent polymer particle layer 4 having superabsorbent polymer particles, and a first wood pulp fiber layer having wood pulp fibers. A pulp fiber layer 5 is formed, and the absorbent layer 9 is laid on the bottom material 1. The first superabsorbent polymer (SAP) granule layer 3 is laid on the absorbent layer 9. The cellulose fibers on the upper surface of the bottom material 1 are fixedly connected to a portion of the surface of the SAP granules in the absorbent layer 9. The first wood pulp fiber layer 5 is laid on the first SAP granule layer 3, and the second SAP granule layer 4 is laid on the first wood pulp fiber layer 5. The average basis weight of both the first SAP granule layer 3 and the second SAP granule layer 4 is 5 g / m³. 2 ~50g / m 2 The preferred value is 10g / m 2 The absorbent paper body has an absorption capacity of not less than 452 g / m² when measured under a pressure of 5.4 kPa.

[0056] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0057] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0058] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0059] Although the invention has been specifically shown and described in conjunction with preferred embodiments, those skilled in the art should understand that various changes in form and detail may be made to the invention without departing from the spirit and scope of the invention as defined in the appended claims, all of which shall be within the scope of protection of the invention.

Claims

1. A wood pulp wet-dry mixed absorbent paper, characterized in that: The absorbent paper includes a body, defined as extending longitudinally along its length and laterally along its width. The absorbent paper comprises a bottom material, a top material, and an absorbent material layer disposed between the bottom and top materials. The absorbent material layer includes a first and a second layer of superabsorbent polymer (SAP) particles, and a first layer of wood pulp fibers. The first SAP particle layer is laid on top of the bottom material. Cellulose fibers on the upper surface of the bottom material are fixedly connected to a portion of the surface of the SAP particles in the first SAP particle layer. The first wood pulp fiber layer is laid on top of the first SAP particle layer, and the second SAP particle layer is laid on top of the first wood pulp fiber layer. The average basis weight of both the first and second SAP particles is 5 g / m² to 50 g / m². The absorbent paper body has an absorption capacity of not less than 452 g / m² measured under a pressure of 5.4 kPa.

2. The wood pulp wet-dry mixed absorbent paper according to claim 1, characterized in that: The average weight of the first superabsorbent polymer (SAP) granule layer is not less than the average weight of the second SAP granule layer.

3. The wood pulp wet-dry mixed absorbent paper according to claim 1, characterized in that: The absorbent material layer further includes a third superabsorbent polymer granule layer and a second wood pulp fiber layer, wherein the second wood pulp fiber layer is laid on the second superabsorbent polymer granule layer and the third superabsorbent polymer granule layer is laid on the second wood pulp fiber layer.

4. The wood pulp wet-dry mixed absorbent paper according to any one of claims 1 to 3, characterized in that: The absorbent material layer has at least one channel along the longitudinal direction that does not contain superabsorbent polymer particles and wood pulp fibers, and the top layer material and the bottom layer material are compositely connected at the channel.

5. A type of absorbent paper made from a mixture of wet and dry wood pulp, characterized in that: The absorbent paper includes a body, defined as extending longitudinally along its length and laterally along its width. The absorbent paper comprises a bottom material, a top material, and an absorbent material layer disposed between the bottom and top materials. The absorbent material layer includes an absorbent layer composed of a mixture of superabsorbent polymer particles and wood pulp fibers, a first superabsorbent polymer particle layer and a second superabsorbent polymer particle layer, and a first wood pulp fiber layer. The absorbent layer is laid on the bottom material. The cellulose fibers on the surface are fixedly connected to a portion of the surface of the superabsorbent polymer particles in the absorbent layer. The first superabsorbent polymer particle layer is laid on the absorbent layer, the first wood pulp fiber layer is laid on the first superabsorbent polymer particle layer, and the second superabsorbent polymer particle layer is laid on the first wood pulp fiber layer. The average basis weight of the first and second superabsorbent polymer particle layers is 5 g / m² to 50 g / m². The absorbent paper body has an absorption capacity of not less than 452 g / m² when measured under a pressure of 5.4 kPa.

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