An adhesive compounding device and its usage method for preparing medical nursing pads

Abstract

The present invention discloses a sizing and laminating device and a usage method for preparing a medical nursing pad, which relates to the technical field of laminated products. The sizing and laminating device includes: an equipment frame, a top conveying mechanism, a core layer conveying mechanism, and a bottom conveying mechanism that are sequentially installed inside the equipment frame from top to bottom, and a first laminating mechanism installed inside the equipment frame near one end; two sizing mechanisms are arranged between the first laminating mechanism and the core layer conveying mechanism; by increasing the humidity of the core layer base material, the formed liquid bridge network and humidity gradient not only enhance the bonding force between fibers, reduce fiber brittleness, but also optimize the penetration of glue in the deep layer of fibers, improve the interfacial bonding force, enhance the bonding strength of the nursing pad after sizing, and at the same time eliminate the electrostatic adsorption effect, enable SAP particles to be evenly embedded in the fiber network, avoid agglomeration and voids. The whole process has a high degree of automation and significantly improves production efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of laminated products, particularly to the use of adhesives, and specifically to a gluing and laminating device and its usage method for preparing medical nursing pads. Background Art

[0002] As an important sanitary product, nursing pads are widely used in various occasions such as hospitals, nursing homes, and families to absorb and manage body fluids, such as urine, sweat, etc., in order to keep patients clean and comfortable. The structure of traditional nursing pads mainly consists of a bottom polyethylene (PE) film, a top non-woven fabric, and a composite core layer located between the two. The composite core layer is usually composed of fluff pulp and superabsorbent polymer (SAP) mixed together. Among them, the fluff pulp provides a good fiber network structure, which helps the rapid absorption and diffusion of liquids, while SAP ensures the high liquid absorption performance of the nursing pad with its excellent water absorption and water locking ability.

[0003] In the preparation process of traditional nursing pads, first, SAP particles need to be evenly scattered on the surface of the fluff pulp, and then the two are tightly combined through a pressing action to form a composite core layer. Next, glue is coated on the inner sides of the PE film and the non-woven fabric, and then they are bonded to the composite core layer to finally form the overall structure of the nursing pad, that is, the PE film as the bottom layer, the composite core layer in the middle, and the non-woven fabric covering the top. By making full use of the characteristics of each layer of materials, the rapid absorption, diffusion, and locking of liquids are achieved, while keeping the surface of the pad dry and comfortable.

[0004] In the steps such as SAP scattering and bonding in the traditional preparation process, it often relies on manual operation or simple mechanical equipment, which not only leads to low production efficiency but also makes it difficult to ensure the consistency and stability of products. Especially on high-speed production lines, how to ensure the even scattering of SAP particles and the firmness of glue bonding has become a key factor restricting production efficiency and product quality. Summary of the Invention

[0005] The present invention overcomes the deficiencies of the prior art and provides a gluing and laminating device and its usage method for preparing medical nursing pads.

[0006] To achieve the above object, the technical solution adopted by the present invention is: a gluing and laminating device for preparing medical nursing pads, comprising: an equipment frame, a top layer conveying mechanism, a core layer conveying mechanism, and a bottom layer conveying mechanism that are sequentially installed from top to bottom inside the equipment frame, and a first laminating mechanism installed inside the equipment frame near one end for laminating the top layer, core layer, and bottom layer substrates into a sandwich structure;

[0007] Between the first composite mechanism and the core layer conveying mechanism, there are two gluing mechanisms for spraying adhesives onto one side of the core layer substrate facing the top and bottom base materials respectively; in the direction of the core layer conveying mechanism towards the first composite mechanism, there are two humidity spraying mechanisms, a SAP spraying mechanism, and a second composite mechanism arranged in sequence;

[0008] The two humidity spraying mechanisms are symmetrically arranged at the top and bottom of the core layer substrate in sequence, and are used to pre-increase and post-increase the humidity of the core layer substrate in sequence; the SAP spraying mechanism is used to spray the core layer substrate with the intercalated polymer water-absorbing resin; the second composite mechanism is used to composite the polymer water-absorbing resin and the core layer substrate into the core layer.

[0009] In a preferred embodiment of the present invention, the humidity spraying mechanism includes: a plurality of mounting plates fixed inside the equipment frame, a connecting plate arranged on one side of the plurality of mounting plates, and a plurality of spraying heads fixed on the connecting plate; one end of the spraying head is equipped with a water delivery head for externally connecting a water delivery device to achieve water source supply; a cylinder is fixed on one side of the mounting plate, and the output end of the cylinder is fixed to one side of the connecting plate.

[0010] In a preferred embodiment of the present invention, the spraying ends of the plurality of spraying heads face the surface of the core layer substrate and are evenly distributed on the connecting plate in a linear array manner; one side of the connecting plate is slidably connected to one side of the mounting plate.

[0011] In a preferred embodiment of the present invention, the gluing mechanism includes: a melting glue cylinder fixed inside the equipment frame, a heating layer arranged inside the melting glue cylinder, and a plurality of glue spraying heads fixed on one side of the melting glue cylinder; a plurality of glue delivery heads are installed on the other side of the melting glue cylinder for externally connecting a glue delivery device to achieve adhesive supply.

[0012] In a preferred embodiment of the present invention, the heating layer realizes the change of the liquid form of the adhesive through heat radiation or heat conduction; the glue spraying ends of the plurality of glue spraying heads face one side of the top layer or the bottom layer material facing the core layer substrate and are evenly distributed on the melting glue cylinder in a linear array manner.

[0013] In a preferred embodiment of the present invention, the SAP spraying mechanism includes: a blanking cone cylinder arranged between the humidity spraying mechanism and the second composite mechanism, and a feeding head installed on one side of the blanking cone cylinder for externally connecting a feeding device to achieve the supply of the polymer water-absorbing resin; the side surface of the blanking cone cylinder is fixed to the inside of the equipment frame, and the blanking end faces the top of the core layer substrate.

[0014] The present invention provides a method for using a gluing and composite equipment for preparing a medical nursing pad, including the following steps:

[0015] S1. Thread the top-layer substrate, the core-layer substrate, and the bottom-layer substrate through the top-layer conveying mechanism, the core-layer conveying mechanism, and the bottom-layer conveying mechanism in sequence, and drive the three to feed towards the first compounding mechanism.

[0016] S2. During the feeding of the core-layer substrate, through two groups of humidity spraying mechanisms, according to the target humidity of the core-layer substrate, first perform primary atomizing spraying for humidity pre-increase, and then perform secondary atomizing spraying for humidity post-increase.

[0017] S3. Through the SAP spraying mechanism, spray the chimeric superabsorbent polymer resin on the top of the core-layer substrate with a certain time interval of increased humidity, and compound the superabsorbent polymer resin and the core-layer substrate into the core layer through the second compounding mechanism.

[0018] S4. Through two groups of gluing mechanisms, spray adhesives on the sides of the top-layer substrate and the bottom-layer substrate facing the core-layer substrate respectively, and compound the top-layer substrate, the core-layer substrate, and the bottom-layer substrate into a nursing pad with a sandwich structure through the first compounding mechanism.

[0019] In a preferred embodiment of the present invention, in the step of S2, the target humidity is 4-10% of the total mass of the core-layer substrate.

[0020] In a preferred embodiment of the present invention, in the step of S2, the spraying direction of the primary atomizing spraying is the top of the core-layer substrate, and the spraying direction of the secondary atomizing spraying is the bottom of the core-layer substrate.

[0021] In a preferred embodiment of the present invention, in the step of S3, the time interval is 6-15 s.

[0022] The present invention solves the defects existing in the background technology, and the present invention has the following beneficial effects:

[0023] The present invention provides an equipment and a use method for gluing and compounding in the preparation of a medical nursing pad. By increasing the humidity of the core-layer substrate to form a liquid bridge network and a humidity gradient, it not only enhances the bonding force between fibers, reduces fiber brittleness, but also optimizes the penetration of glue in the deep layer of fibers, improves the interfacial bonding force, enhances the bonding strength of the nursing pad after gluing, and at the same time eliminates the electrostatic adsorption effect, enables the SAP particles to be evenly embedded in the fiber network, avoids agglomeration and voids, and the entire process has a high degree of automation, significantly improving the production efficiency.

[0024] In the present invention, by first pre-increasing the humidity at the top of the core layer substrate, moisture penetrates through capillary action of fibers to form a liquid bridge network first, neutralize the static electricity on the fiber surface, and form a humidity gradient with higher humidity inside than on the surface layer, avoiding over-wetting of the surface layer caused by one-time spraying, which affects subsequent SAP dispersion and glue penetration. On the basis of pre-penetration, humidity is increased at the bottom of the core layer substrate later, accelerating the diffusion of moisture at the top with the liquid bridge network formed by pre-penetration, avoiding the accumulation of moisture on the surface layer, reducing the risk of caking, and at the same time achieving humidity balance between the inside and the surface layer of the fiber, ensuring the uniformity of subsequent SAP dispersion and glue coating.

[0025] In the present invention, by precisely controlling the interval time from after humidity increase to before spraying SAP particles, the moisture after humidity increase can uniformly penetrate into the core layer substrate, avoiding excessive concentration of moisture in local areas, reducing agglomeration or uneven dispersion of SAP particles caused by uneven water absorption, and the phenomenon of hindering glue penetration, and avoiding too long intervals from affecting the production line efficiency, so as to ensure the efficiency of gluing and lamination while balancing moisture diffusion and static electricity elimination. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings;

[0027] Figure 1 is a three-dimensional structure diagram of the gluing and laminating equipment of the preferred embodiment of the present invention;

[0028] Figure 2 is the overall half-sectional structure and partial enlarged view of the gluing and laminating equipment of the preferred embodiment of the present invention;

[0029] Figure 3 In (a) is a physical diagram of the nursing pad prepared in Example 1, and in (b) is a physical diagram of the nursing pad prepared in Comparative Example 1;

[0030] In the figure: 1. Equipment frame; 11. Top layer conveying mechanism; 12. Core layer conveying mechanism; 13. Bottom layer conveying mechanism; 2. First lamination mechanism; 3. Gluing mechanism; 31. Melt glue cylinder; 32. Heating layer; 33. Glue spraying head; 4. Humidity spraying mechanism; 41. Installation plate; 42. Connecting plate; 43. Spraying head; 44. Water delivery head; 45. Cylinder; 5. SAP spraying mechanism; 51. Feeding cone; 52. Feeding head; 6. Second lamination mechanism. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0032] In the following description, many specific details are set forth in order to provide a thorough understanding of the present invention. However, the present invention may be practiced in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited by the specific embodiments disclosed below.

[0033] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the protection scope of the present application. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Therefore, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more.

[0034] In the description of the present application, it should be noted that, unless otherwise clearly defined and limited, the terms "mounted", "connected", "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0035] Application Overview:

[0036] As a key hygiene product, the performance and quality of the nursing pad are directly related to the user experience and health status of patients. Although the preparation process of traditional nursing pads meets the basic market needs to a certain extent, there are still many technical challenges in the actual production process;

[0037] When preparing the composite core layer of a nursing pad, fluff pulp, as an important fiber material, its humidity state plays a crucial role in the dispersion of SAP (superabsorbent polymer), the adhesion between fibers, and the subsequent penetration of glue. Traditional preparation processes often neglect the precise control of the humidity of fluff pulp, resulting in the fluff pulp being too dry. This not only makes it difficult for SAP particles to be evenly dispersed in the fiber network, affecting the liquid absorption performance of the core layer, but also because the dry fiber surface is prone to accumulating static electricity, further exacerbating the agglomeration of SAP, forming local accumulations or voids, and severely weakening the overall performance of the nursing pad.

[0038] At the same time, the overly dry fluff pulp may also lead to a decrease in the glue bonding strength, because it is difficult for the dry fibers to form an effective bond with the glue, increasing the risk of delamination or peeling between the core layer and the PE film / non-woven fabric. This is particularly prominent on high-speed production lines, because the improvement of production efficiency is often accompanied by less attention to the details of material handling, thus exacerbating the instability of product quality.

[0039] In view of the above problems, through research and practice, the important impact of fluff pulp humidity control on the nursing pad preparation process and product quality has been discovered. To solve this technical problem, the present invention proposes an innovative gluing and composite equipment and its usage method for the preparation of medical nursing pads, aiming to optimize the humidity state of fluff pulp through precise humidity control technology, thereby improving the dispersion of SAP, enhancing the adhesion strength between fibers, and improving the penetration effect of glue.

[0040] As Figure 1 and Figure 2 shown, an innovative gluing and composite equipment for the preparation of medical nursing pads includes: an equipment frame 1, a top conveying mechanism 11, a core layer conveying mechanism 12, and a bottom conveying mechanism 13 that are sequentially installed inside the equipment frame 1 from top to bottom, and a first composite mechanism 2 installed near one end inside the equipment frame 1 for laminating the top, core layer, and bottom substrates into a sandwich structure; between the first composite mechanism 2 and the core layer conveying mechanism 12, there are provided two gluing mechanisms 3 for spraying adhesives onto one side of the top and bottom substrates facing the core layer substrate respectively; on the direction of the core layer conveying mechanism 12 towards the first composite mechanism 2, there are sequentially provided two humidity spraying mechanisms 4, an SAP spraying mechanism 5, and a second composite mechanism 6; the two humidity spraying mechanisms 4 are symmetrically arranged on the top and bottom of the core layer substrate in sequence for sequentially pre-increasing and post-increasing the humidity of the core layer substrate; the SAP spraying mechanism 5 is used for spraying the superabsorbent polymer onto the core layer substrate; the second composite mechanism 6 is used for laminating the superabsorbent polymer and the core layer substrate into a core layer.

[0041] It should be noted that the specific structures of the top-layer conveying mechanism 11, the core-layer conveying mechanism 12, and the bottom-layer conveying mechanism 13 are the same. A plurality of conveying rollers are rotatably installed in the feeding direction inside the equipment frame 1, and each group of conveying rollers includes two conveying rollers rotating in opposite directions up and down. A power source that can be installed inside the equipment frame 1 is used in cooperation with the plurality of groups of conveying rollers to realize the feeding operations of the top-layer, core-layer, and bottom-layer base materials. The specific structures of the first composite mechanism 2 and the second composite mechanism 6 are the same. They both include two composite rollers rotatably installed inside the equipment frame 1 and rotating in opposite directions up and down. A power source that can be installed inside the equipment frame 1 is used in cooperation with several composite rollers to realize the composite forming of the core layer or the nursing pad. The specific structure of the power source is a mechanical structure that can transfer rotational motion in the prior art and belongs to the common knowledge in the field. Therefore, the control method and structure are not explained in detail in this application and will not be elaborated here.

[0042] Specifically, the equipment frame 1 serves as the support foundation. The top-layer conveying mechanism 11, the core-layer conveying mechanism 12, and the bottom-layer conveying mechanism 13 are installed in sequence to respectively realize the feeding operations of the top-layer, core-layer, and bottom-layer base materials. The humidity spraying mechanism 4, the SAP spraying mechanism 5, and the second composite mechanism 6 are sequentially arranged on the core-layer conveying mechanism 12, which are used to respectively perform humidity pretreatment on the core-layer base material, add SAP functional materials, and composite the superabsorbent resin with the core-layer base material to form the core layer. At the same time, two gluing mechanisms 3 are used to spray adhesives on one side of the top-layer and bottom-layer base materials facing the core layer. The first composite mechanism 2 is responsible for composite the three-layer base materials into a sandwich structure to achieve firm bonding. The entire process has a high degree of automation and significantly improves production efficiency.

[0043] In some embodiments, the humidity spraying mechanism 4 includes: a plurality of mounting plates 41 fixed inside the equipment frame 1, a connecting plate 42 arranged on one side of the plurality of mounting plates 41, and a plurality of spraying heads 43 fixed on the connecting plate 42. One end of the spraying head 43 is equipped with a water delivery head 44 for externally connecting a water delivery device to achieve water source supply. A cylinder 45 is fixed on one side of the mounting plate 41, and the output end of the cylinder 45 is fixed to one side of the connecting plate 42.

[0044] It should be noted that the spraying ends of the plurality of spraying heads 43 face the surface of the core-layer base material and are evenly distributed on the connecting plate 42 in a linear array manner. One side of the connecting plate 42 is slidably connected to one side of the mounting plate 41.

[0045] Specifically, it is fixed on the equipment frame 1 through the mounting plate 41. The connecting plate 42 is slidably connected to the mounting plate 41. The cylinder 45 pushes the connecting plate 42 to move, so as to adjust the distance between a plurality of spray heads 43 on the connecting plate 42 and the surface of the core layer substrate. At the same time, the water inlet head 44 is externally connected to a water supply device to provide water source for the spray heads 43. The spray heads 43 spray the water source in an atomized manner, realizing pre-increase and post-increase of humidity. And because a plurality of spray heads 43 are distributed in a linear array, it ensures uniform humidity spraying, helps to improve the moisture absorption performance of the core layer substrate, and provides favorable conditions for subsequent embedding of the superabsorbent polymer resin.

[0046] In some embodiments, the gluing mechanism 3 includes: a glue melting cylinder 31 fixed inside the equipment frame 1, a heating layer 32 arranged inside the glue melting cylinder 31, and a plurality of glue spraying heads 33 fixed on one side of the glue melting cylinder 31; a plurality of glue feeding heads are installed on the other side of the glue melting cylinder 31 for externally connecting a glue feeding device to realize the supply of the adhesive.

[0047] It should be noted that the heating layer 32 realizes the change of the adhesive in liquid form through heat radiation or heat conduction; the glue spraying ends of the plurality of glue spraying heads 33 face the side of the top layer or the bottom layer material facing the core layer substrate, and are evenly distributed on the glue melting cylinder 31 in a linear array.

[0048] Specifically, the glue feeding head externally connects a glue feeding device to provide the adhesive for the glue melting cylinder 31. The heating layer 32 in the glue melting cylinder 31 is used to heat the adhesive through heat radiation or heat conduction, so that it changes from semi-solid state to liquid state, ensuring the spraying effect. Since the glue spraying heads 33 on one side of the glue melting cylinder 31 are distributed in a linear array, it ensures that the adhesive is evenly sprayed on the side of the top layer or the bottom layer substrate facing the core layer, helps to improve the bonding strength between the three-layer substrates, and ensures the overall performance of the medical nursing pad.

[0049] In some embodiments, the SAP spraying mechanism 5 includes: a feeding cone 51 arranged between the humidity spraying mechanism 4 and the second composite mechanism 6, and a feeding head 52 installed on one side of the feeding cone 51 for externally connecting a feeding device to realize the supply of the superabsorbent polymer resin; the side of the feeding cone 51 is fixed to the inner side of the equipment frame 1, and the feeding end faces the top of the core layer substrate.

[0050] Specifically, the feeding head 52 externally connects a feeding device to provide the superabsorbent polymer resin for the feeding cone 51. The feeding cone 51 evenly sprays the superabsorbent polymer resin on the core layer substrate, so that it evenly embeds the superabsorbent polymer resin in the core layer substrate, which helps to improve the overall comfort and use effect of the medical nursing pad.

[0051] A method for using an upper gluing and composite device for preparing a medical nursing pad includes the following steps:

[0052] S1. Pass the top-layer substrate, core-layer substrate, and bottom-layer substrate through the top-layer conveying mechanism 11, core-layer conveying mechanism 12, and bottom-layer conveying mechanism 13 in sequence, and drive the three to feed towards the first compounding mechanism 2;

[0053] S2. During the feeding of the core-layer substrate, through two groups of humidity spraying mechanisms 4, according to the target humidity of the core-layer substrate, first perform primary atomizing spraying to pre-increase the humidity, and then perform secondary atomizing spraying to post-increase the humidity;

[0054] S3. Through the SAP spraying mechanism 5, spray the chimeric high-molecular water-absorbing resin on the top of the core-layer substrate with a certain time interval of increased humidity, and compound the high-molecular water-absorbing resin and the core-layer substrate into the core layer through the second compounding mechanism 6;

[0055] S4. Through two groups of gluing mechanisms 3, spray adhesives on one side of the top-layer and bottom-layer substrates facing the core-layer substrate respectively, and compound the top-layer, core-layer, and bottom-layer substrates into a nursing pad with a sandwich structure through the first compounding mechanism 2.

[0056] In some embodiments, in step S2, the target humidity is 4-10% of the total mass of the core-layer substrate.

[0057] In some embodiments, in step S2, the spraying direction of the primary atomizing spraying is the top of the core-layer substrate, and the spraying direction of the secondary atomizing spraying is the bottom of the core-layer substrate.

[0058] In some embodiments, in step S3, the time interval is 6-15 s.

[0059] To further make the object and effect of the present invention simple and easy to understand, the present invention is further elaborated in combination with the following specific examples and comparative examples; wherein the top-layer substrate is non-woven fabric, the core-layer substrate is fluffed pulp pressed into sheets, for every 100 kg of fluffed pulp, the water content is 2 kg, the bottom-layer substrate is a PE film, and the particle size of the high-molecular water-absorbing resin is 100 mesh. Example 1

[0060] A method for using an adhesive compounding device for preparing a medical nursing pad, comprising the following steps:

[0061] S1. Pass the non-woven fabric, fluffed pulp, and PE film through the top-layer conveying mechanism 11, core-layer conveying mechanism 12, and bottom-layer conveying mechanism 13 in sequence, and drive the three to feed towards the first compounding mechanism 2;

[0062] S2. During the feeding of the fluffed pulp, through two groups of humidity spraying mechanisms 4, according to the target humidity of 8%, first spray 1.8 kg of water onto the top of the fluffed pulp with every 100 kg of fluffed pulp as the total mass for primary atomizing spraying to pre-increase the humidity, and then spray 4.2 kg of water onto the bottom of the fluffed pulp for secondary atomizing spraying to post-increase the humidity;

[0063] S3. Through the SAP spraying mechanism 5, spray SAP onto the top of the fluff pulp after the humidity has increased for 11 s, and compound the SAP and the fluff pulp into the core layer through the second compounding mechanism 6;

[0064] S4. Through two groups of sizing mechanisms 3, spray adhesives onto one side of the non-woven fabric and the PE film facing the core layer respectively, and compound the non-woven fabric, the core layer and the PE film into a nursing pad with a sandwich structure through the first compounding mechanism 2. Example 2

[0065] This example is basically the same as Example 1, the difference is that: in step S2, the target humidity is 10%, spray 2.4 kg of water by the first atomization spraying, and spray 5.6 kg of water by the second atomization spraying. Example 3

[0066] This example is basically the same as Example 1, the difference is that: in step S2, the target humidity is 4%, spray 0.6 kg of water by the first atomization spraying, and spray 1.4 kg of water by the second atomization spraying. Example 4

[0067] This example is basically the same as Example 1, the difference is that: in step S3, the interval time is 6 s. Example 5

[0068] This example is basically the same as Example 1, the difference is that: in step S3, the interval time is 15 s.

[0069] Comparative Example 1

[0070] This comparative example is basically the same as Example 1, the difference is that: in step S2, the target humidity is 2%, and there is no pre-increase and post-increase in humidity.

[0071] Comparative Example 2

[0072] This comparative example is basically the same as Example 1, the difference is that: in step S2, the target humidity is 12%, spray 3 kg of water by the first atomization spraying, and spray 7 kg of water by the second atomization spraying.

[0073] Comparative Example 3

[0074] This comparative example is basically the same as Example 1, the difference is that: step S2 is specifically: during the feeding of the fluff pulp, through a group of humidity spraying mechanisms 4, according to the target humidity of 8%, spray 6 kg of water onto the top of the fluff pulp with a total mass of every 100 kg of fluff pulp for humidity increase.

[0075] Comparative Example 4

[0076] This comparative example is basically the same as Example 1, except that: in step S2, the spraying direction of the primary atomization spraying is the bottom of the fluff pulp, and the spraying direction of the secondary atomization spraying is the top of the fluff pulp.

[0077] Comparative Example 5

[0078] This comparative example is basically the same as Example 1, except that: in step S3, the interval time is 3 s.

[0079] Comparative Example 6

[0080] This comparative example is basically the same as Example 1, except that: in step S3, the interval time is 20 s.

[0081] Performance detection: Referring to GB / T 2792-2014 "Test Method for Peel Strength of Adhesive Tape", the bonding strength of the nursing pads obtained in the above Examples 1-5 and Comparative Examples 1-6 was tested. The average value was taken after parallel testing 3 times, and the agglomeration and dispersion status of SAP in the core layer were observed. The results are shown in Table 1.

[0082] Table 1: Performance test results

[0083]

[0084] From Table 1 and Figure 3 it can be seen that:

[0085] Figure 3 Figures (a) and (b) in it respectively show the physical pictures of the nursing pads prepared after gluing and compounding in Example 1 and Comparative Example 1. Through the comparison between Example 1 and Comparative Example 1, it can be known that by increasing the humidity of the core layer substrate, the surface resistance of the fiber can be reduced, the electrostatic adsorption effect can be eliminated, the SAP particles can be evenly embedded in the fiber network, avoiding agglomeration and voids, and at the same time, the glue can fully penetrate into the deep layer of the fiber, improving the interfacial bonding force, thereby enhancing the bonding strength of the nursing pad after gluing. For a too dry core layer substrate, the surface static electricity increases, resulting in the agglomeration of SAP particles due to electrostatic adsorption, unable to be evenly dispersed in the fiber network, forming local accumulations or voids, making the nursing pad after gluing and compounding have the situation of agglomeration and uneven dispersion, affecting the liquid absorption performance of the core layer, and the glue only stays on the surface layer of the core layer substrate, failing to form an effective bond with the deep layer fibers, thereby reducing the bonding strength of the nursing pad after gluing and being prone to delamination and peeling.

[0086] It can be seen from the comparison between Examples 1-3 and Comparative Example 2 that when the humidity of the core layer substrate is too high, although the electrostatic effect is eliminated, a large amount of water molecules will exist between and inside the fibers. During the bonding process, the glue needs to penetrate between the fibers and form strong interactions such as chemical bonds or hydrogen bonds with the fibers. The increased water molecules due to the increased humidity will occupy the positions of the interactions, making it difficult for them to be tightly bonded, which affects the bonding strength. At the same time, it will also make it more difficult for the SAP particles to be evenly embedded in the fiber network, affecting the penetration and diffusion of the SAP particles, resulting in agglomeration and uneven dispersion.

[0087] It can be seen from the comparison between Example 1 and Comparative Example 3 that by pre-increasing the humidity at the top of the core layer substrate first, the water can penetrate through the capillary action of the fibers to form a liquid bridge network first, neutralize the static electricity on the fiber surface, and form a humidity gradient with a higher humidity inside than on the surface layer, avoiding the over-wetting of the surface layer caused by one-time spraying, which affects the subsequent SAP dispersion and glue penetration. On the basis of pre-penetration, the humidity is increased at the bottom of the core layer substrate later, which accelerates the diffusion of the water at the top with the liquid bridge network formed by pre-penetration, avoids the accumulation of water on the surface layer, reduces the risk of caking, and at the same time realizes the humidity balance between the inside and the surface layer of the fibers, ensuring the uniformity of subsequent SAP dispersion and glue coating; It can be seen from the comparison between Example 1 and Comparative Example 4 that when the humidity is pre-increased at the bottom first and then increased at the top later, it is easy to cause insufficient upward diffusion of water, and then the penetration of the water with the later increased humidity is too slow. When spraying the SAP particles, there is a situation where there is more water remaining on the top surface layer, resulting in more reaction swelling of the sprayed SAP particles, making it difficult to embed into the fiber gaps, being forced to accumulate and agglomerate on the surface layer unevenly, and hindering the downward penetration of the glue, resulting in uneven distribution of the glue layer.

[0088] It can be seen from the comparison between Example 1 and Examples 4-5 and Comparative Examples 5-6 that by precisely controlling the interval time from after increasing the humidity to before spraying the SAP particles, the water after increasing the humidity can be evenly penetrated into the core layer substrate, avoiding the excessive concentration of water in local areas, reducing the agglomeration or uneven dispersion of the SAP particles caused by uneven water absorption, and the phenomenon of hindering the glue penetration, and avoiding the too long interval affecting the production line efficiency, so as to ensure the efficiency of gluing and compounding while balancing the water diffusion and static electricity elimination.

[0089] Based on the inspiration of the ideal embodiments of the present invention, through the above description, for those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claims involved.

[0090] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for preparing a medical nursing pad, the method being implemented by a gluing and laminating device, characterized in that: The gluing and compounding equipment comprises: an equipment frame, a top layer conveying mechanism, a core layer conveying mechanism and a bottom layer conveying mechanism sequentially installed on the inner side of the equipment frame from top to bottom, and a first compounding mechanism installed on the inner side of the equipment frame near one end for compounding the top layer, the core layer and the bottom layer into a sandwich structure; Two groups of gluing mechanisms are arranged between the first compounding mechanism and the core layer conveying mechanism for spraying adhesive respectively on the top layer and bottom layer substrates facing the core layer substrate; two groups of humidity spraying mechanisms, a SAP spraying mechanism and a second compounding mechanism are arranged in sequence in the direction of the core layer conveying mechanism toward the first compounding mechanism; The two groups of humidity spraying mechanisms are sequentially arranged at the top and bottom of the core layer substrate, and are used to pre-increase the humidity by spraying 30% of the total amount of the target humidity according to the target humidity of the core layer substrate, and then to increase the humidity by spraying 70% of the total amount of the target humidity; the SAP spraying mechanism is used to spray the embedded polymer water-absorbing resin on the core layer substrate; the second composite mechanism is used to composite the polymer water-absorbing resin and the core layer substrate into a core layer; The target humidity is 4-10% of the total mass of the core substrate; the spraying direction of the primary atomization spray is the top of the core substrate, and the spraying direction of the secondary atomization spray is the bottom of the core substrate; The preparation method of the medical nursing pad comprises the following steps: S1, respectively passing the top layer, the core layer substrate and the bottom layer through the top layer conveying mechanism, the core layer conveying mechanism and the bottom layer conveying mechanism in sequence, and driving the three to feed toward the first composite mechanism; S2, during the feeding of the core layer substrate, two groups of humidity spraying mechanisms are used to pre-increase the humidity by atomizing spraying once, and then post-increase the humidity by atomizing spraying twice according to the target humidity of the core layer substrate; S3, spraying the embedded polymer water-absorbing resin on the top of the core layer substrate 6-15 seconds after the humidity increases through the SAP spraying mechanism, and compounding the polymer water-absorbing resin and the core layer substrate into a core layer through the second compounding mechanism; S4. Use two sets of gluing mechanisms to spray adhesive on the top layer and bottom layer substrates facing the core layer substrate respectively, and use the first compounding mechanism to compound the top layer, the core layer and the bottom layer into a nursing pad with a sandwich structure.

2. The method for preparing a medical nursing pad according to claim 1, characterized in that: The humidity spraying mechanism comprises: a plurality of mounting plates fixed on the inner side of the equipment frame, a connecting plate arranged on one side of the mounting plates, and a plurality of spraying heads fixed on the connecting plates; a water delivery head is installed at one end of the spraying head for connecting an external water delivery device to realize water supply; a cylinder is fixed on one side of the mounting plate, and an output end of the cylinder is fixed to one side of the connecting plate.

3. The method for preparing a medical nursing pad according to claim 2, characterized in that: The spraying ends of the plurality of spraying heads face the surface of the core layer substrate and are evenly distributed on the connecting plate in a linear array; one side of the connecting plate is slidably connected to one side of the mounting plate.

4. The method for preparing a medical nursing pad according to claim 1, characterized in that: The gluing mechanism includes: a melt-glue cylinder fixed on the inner side of the equipment frame, a heating layer arranged inside the melt-glue cylinder, and a plurality of glue spray heads fixed on one side of the melt-glue cylinder; a plurality of glue delivery heads are installed on the other side of the melt-glue cylinder for connecting to an external glue delivery device to realize adhesive supply.

5. The method for preparing a medical nursing pad according to claim 4, characterized in that: The heating layer realizes the change of the liquid form of the adhesive by means of heat radiation or heat conduction; the spray ends of several of the spray heads face the top layer or the bottom layer material facing the side of the core layer substrate, and are evenly distributed on the melt cylinder in a linear array.

6. The method for preparing a medical nursing pad according to claim 1, characterized in that: The SAP spraying mechanism includes: a discharge cone cylinder arranged between the humidity spraying mechanism and the second composite mechanism, and a feeding head installed on one side of the discharge cone cylinder for external feeding equipment to realize the supply of polymer water-absorbing resin; the side surface of the discharge cone cylinder is fixed to the inner side of the equipment frame, and the discharge end faces the top of the core layer substrate.

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