A process for manufacturing a diaper absorbent core with fluffy fiber components

Abstract

The present invention discloses a process for producing a diaper absorbent core having a fluffy fiber component. The process comprises: pre-treating low-melting-point fibers and plant fibers, mixing them with a polymer material in a mixing device, and then air-laying them to form a composite; drying and cooling the composite in an oven; spreading the polymer material on the surface of the cooled composite, spraying glue, and laminating it with a surface layer to form an absorbent core; and finally rolling it up for use. The present invention forms a diaper absorbent core by forming a composite polymer material with a staggered structure of mixed fibers and coating the mixed material with a surface layer and a bottom layer. This greatly improves the absorbent core's absorption capacity and efficiency, making the overall structure soft, comfortable, and stable, while also having good diffusion capacity and a dry surface.

Description

Technical Field

[0001] The invention relates to the technical field of diaper absorbent cores, in particular to a process for manufacturing diaper absorbent cores with fluffy fiber components. Background Art

[0002] Absorbent hygiene products, such as diapers, generally consist of a liquid-permeable topsheet (primarily in contact with the skin), a liquid-impermeable backsheet (non-skin contact), and an absorbent core layer between the two. The absorbent core layer primarily absorbs, stores, and locks in body fluids, making it a key structural component in determining the absorbent performance of absorbent hygiene products.

[0003] The absorbent core layer is generally designed with hydrophilic fibers and polymer absorbent resin particles in a certain proportion and structural distribution. With the development of ultra-thin absorbent sanitary products such as diapers, the common absorbent core bulk fiber molding method is mainly composed of an upper layer: hydrophilic fibers, a middle layer: a uniform mixture of hydrophilic fibers and polymer absorbent resin particles, and a bottom layer: hydrophilic fibers. The three-layer structure is formed by spraying hot melt adhesive, commonly known as a "sandwich" hybrid absorbent core. However, because hydrophilic fibers do not have a capillary structure, they cannot conduct fecal fluid multiple times after absorbing water, resulting in slow overall absorption efficiency. After the hydrophilic fibers absorb feces for the first time, they will be filled with feces, which is not conducive to the subsequent absorption of feces. It can easily lead to the core absorbing feces in a timely manner and causing leakage and other usage problems. In addition, hydrophilic fibers are non-degradable materials, and if they account for too large a proportion in the absorbent core, it will have a certain impact on the environment.

[0004] Currently, there is a need for a fiber structure that can accelerate absorption and occupy less space to lock polymer absorbent resin particles. Plant fibers have been a focus of attention because they have a capillary structure that can absorb fecal fluid multiple times, facilitating the transfer of fecal fluid with polymer materials and accelerating absorption. However, plant fibers are too short to provide a stable structure, and hydrophilic fibers are too long to be combed and formed, resulting in complex processing and structure, which affects the water absorption and expansion of the polymer. Therefore, how to make 8-30mm low-melting point fibers, plant fibers, and polymer materials air-lay and mix them together to form a stable composite structure with good absorption efficiency has become a problem that needs to be solved. Summary of the Invention

[0005] In view of the technical defects existing in the background technology, the present invention proposes a process for manufacturing a diaper absorbent core with a fluffy fiber component, which solves the above technical problems and meets practical needs. The specific technical solution is as follows:

[0006] A process for producing a diaper absorbent core having a fluffy fiber component, comprising:

[0007] Step S1: low-melting-point fibers with a fiber length of 8-30 mm and plant fibers are pretreated to form mixed fibers with a relative content of low-melting-point fibers of 10-40%, the mixed fibers are added together with a polymer material into a mixing device, and after mixing, air-laid to form a composite;

[0008] Step S2: After the composite comes out of the mixing device, it enters the oven for drying until the relative moisture content of the composite is 6-10%, and then passes through a cooling device to cool and set;

[0009] Step S3: Sprinkling polymer material on the surface of the dried composite, spraying glue on the surface and laminating the surface layer with a pressing roller to form an absorbent core;

[0010] Step S4: The absorbent core is rolled up by a winding roller.

[0011] As a further technical solution of the present invention, the preprocessing in step S1 includes the following steps:

[0012] Step a1: The low-melting-point fibers and plant fibers are loosened by a coarse loosening device and stored in a fiber storage tank;

[0013] Step a2: The low-melting point fiber and plant fiber are taken from the fiber storage tank by a fine loosening device and mixed into a crusher to form a mixed fiber with a relative content of low-melting point fiber of 10-40%. After mixing, the mixed fiber is transported to the mixing equipment via a feeding fan.

[0014] As a further technical solution of the present invention, the post-mixing air-laying in step S1 includes the following steps:

[0015] Step b1: the mixed fibers enter the mixing device from the upper air chamber at the upper end of the mixing device, are broken up by the first roller group of the mixing device, and then fall into the polymer mixing chamber of the mixing device;

[0016] Step b2: The polymer material enters the polymer mixing chamber through the polymer feeding group of the mixing equipment and is mixed with the low-melting-point fiber and the plant fiber, and then is mixed and broken up by the second roller group to form a core mixed material;

[0017] Step b3: the core mixed material is dispersed and mixed and then falls into the negative pressure air cavity of the mixing equipment, and is evenly dropped onto the forming mesh belt covered with the composite bottom layer by the downward negative pressure wind force to form a composite body.

[0018] As a further technical solution of the present invention, the manufacturing process of the composite bottom layer in step b3 includes the following steps:

[0019] Step c1: The pre-treated low-melting point fibers and plant fibers with a fiber length of 8-30 mm are fed into the mixing device from the upper air chamber at the upper end of the mixing device, are broken up by the first roller group of the mixing device, and then fall into the polymer mixing chamber of the mixing device;

[0020] Step c2: The second roller group mixes and breaks up the mixture, and then falls into the negative pressure air chamber of the mixing equipment. The downward negative pressure wind force evenly falls on the forming mesh belt covered with the bottom layer to form a composite bottom layer.

[0021] As a further technical solution of the present invention, the oven temperature in step S3 is 110-140° C., and the distance between the upper pressing roller and the lower pressing roller in step S3 is adjustable.

[0022] A mixing device for raw materials of an absorbent core, comprising a mixing device and a feeding device and a negative pressure device connected thereto, wherein the mixing device comprises an upper air chamber, a first roller group, a polymer mixing chamber, a second roller group, a negative pressure air chamber, a negative pressure lower air chamber, and a forming mesh belt arranged between the negative pressure air chamber and the negative pressure lower air chamber, wherein the upper end of the upper air chamber is provided with a ventilation top cover connecting the inside and outside of the mixing device, at least one fiber feed port is provided on the side wall of the upper air chamber and is connected to the feeding device, and at least one group of first rollers is provided between the upper air chamber and the polymer mixing chamber Roller group, the first roller group includes at least two breaking up rollers, at least one polymer feed port connected to the outside is provided on the side wall of the polymer mixing chamber, the polymer feed port connects the polymer mixing chamber and the polymer feed group, at least one second roller group is provided between the negative pressure air chamber and the polymer mixing chamber, the second roller group includes at least four breaking up rollers, the forming mesh belt is arranged around the negative pressure lower air chamber, the lower end of the negative pressure lower air chamber is provided with a mesh belt correction device connected to the forming mesh belt, and the negative pressure lower air chamber is provided with a negative pressure air port connected to the negative pressure device.

[0023] As a further technical solution of the present invention, the feeding device includes a crusher, a feeding pipe connecting the crusher and the fiber feeding port, and a feeding fan arranged at the lower end of the feeding pipe.

[0024] As a further technical solution of the present invention, the beating roller includes a cotton stirring roller, vertical seat bearings provided at both ends of the cotton stirring roller for fixation, and a number of cotton stirring needles evenly arranged around the circumference of the cotton stirring roller. A pressure plate is provided at the connection between the cotton stirring needles and the cotton stirring roller, and sealing plates are also provided at both ends of the cotton stirring roller.

[0025] As a further technical solution of the present invention, the length of the cotton stirring needles of the first roller group is greater than the length of the cotton stirring needles of the second roller group.

[0026] As a further technical solution of the present invention, when the number of the first roller group and the second roller group is greater than two, the roller groups are arranged vertically.

[0027] The beneficial effects of the present invention are:

[0028] (1) The manufacturing process of the absorbent core is to pre-treat the low-melting-point fiber and the plant fiber, loosen the mixed fiber materials at the same time, and facilitate the subsequent interweaving and mixing with the polymer material. Before mixing with the polymer material, the gap between the fiber materials is increased by a scattering roller to facilitate the mixing of the polymer material. After mixing, the fiber materials are evenly mixed again by a scattering roller, and the mixed materials are evenly dropped on the forming mesh belt with the bottom layer. By fully breaking up the fiber materials, a stable coating structure can be provided for the polymer, and the capacity of the polymer material can be increased, thereby ensuring the absorption capacity of the core. By adding plant fibers to the low-melting-point fibers, the stability of the structure can be increased, and the capillary structure of the plant fibers can be used to absorb and transfer feces multiple times, thereby improving the absorption efficiency of the core.

[0029] (2) Before compounding with polymer materials, low-melting-point fibers and plant fibers can be laid on the bottom layer to form a diffusion layer, which can facilitate the core to diffuse the stool liquid to the surrounding areas after absorbing the liquid, thereby improving the absorption capacity and improving the connectivity with the bottom layer structure when compounding with polymer materials.

[0030] (3) Before compounding with the surface layer, a layer of polymer material can be spread on the surface of the mixed fiber to improve the liquid absorption capacity of the surface layer and keep the surface layer dry and comfortable.

[0031] (4) This mixing equipment first breaks up the mixed fibers through the first roller group, thereby improving the mixing efficiency and mixing effect of the polymer materials, improving the construction of the fiber structure and the stability of the overall structure, and then evenly spreads the mixed materials on the bottom layer through the second roller group to facilitate production. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The figure is a schematic flow chart of a process for manufacturing a diaper absorbent core having a fluffy fiber component according to the present invention.

[0033] Figure 2 The figure is a schematic diagram of the cross-sectional structure of an absorbent core of a diaper having a fluffy fiber component according to the present invention.

[0034] Figure 3 This is a schematic diagram of the overall structure of a mixing device for raw materials of an absorbent core according to the present invention.

[0035] Figure 4 This is a side structural schematic diagram of a mixing device for raw materials of an absorbent core according to the present invention.

[0036] Figure 5 A mixing device for raw materials of an absorbent core of the present invention Figure 4Schematic diagram of the AA cross-section structure.

[0037] Figure 6 This is a schematic diagram of the overall structure of a beating roller of a mixing device for raw materials of an absorbent core according to the present invention.

[0038] Wherein: surface layer 1, polymer material 2, mixed fiber 3, bottom layer 4, drying oven 5, spreading polymer material 6, glue spraying 7, cooling device 8, pressing roller 9, coarse loosening device 10, fiber storage tank 11, fine loosening device 12, crusher 13, feeding fan 14, feeding pipe 15, negative pressure device 16, mixing equipment 17, upper air chamber 18, first roller group 19, polymer mixing chamber 20, second roller group 21, negative pressure air chamber 22, negative pressure lower air chamber 23, forming mesh belt 24, ventilation top cover 25, polymer feeding group 26, mesh belt correction device 27, cotton stirring roller 28, bearing with vertical seat 29, cotton stirring punching needle 30, pressure plate 31, sealing plate 32. DETAILED DESCRIPTION

[0039] The following describes the implementation methods of the present invention in conjunction with the accompanying drawings and relevant embodiments. It should be pointed out that the following relevant embodiments are only preferred embodiments for better illustrating the present invention itself, and the implementation methods of the present invention are not limited to the following embodiments. In addition, the present invention relates to the relevant necessary components in this technical field and should be regarded as common knowledge in this technical field, which can be known and mastered by technical personnel in this technical field.

[0040] In the description of the present invention, it should be understood that the terms "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "inner", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the purpose of describing the present invention and simplifying the description, rather than indicating or implying that the devices or elements referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention; in addition, the terms "primary" and "secondary" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features; therefore, it is defined that "primary" and "secondary" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly including one or more such features.

[0041] Example 1 of the manufacturing process of the absorbent core:

[0042] like Figures 1 to 2 As shown, a process for manufacturing a diaper absorbent core having a fluffy fiber component comprises:

[0043] Step S1: low-melting-point fibers with a fiber length of 8-30 mm and plant fibers are pretreated to form mixed fibers 3 with a relative content of low-melting-point fibers of 10-40%. The mixed fibers 3 are added to a mixing device 17 together with a polymer material 2, and after mixing, air-laid to form a composite.

[0044] The low-melting point fibers and the plant fibers have a fiber length of 8-30 mm. This length ensures the amount of the polymer material 2, thereby ensuring the absorptive capacity of the absorbent core. Furthermore, the low-melting point fibers of this length can effectively lock the polymer material 2, ensuring its stability and fluffiness. Excessive length will prevent excessive entanglement with the polymer material 2, affecting its fluffiness and hindering water absorption, while excessive short length will prevent the stability of the polymer material 2. If the low-melting point fibers and the plant fibers are less than 8 mm in length, the insufficient retention length will prevent them from effectively locking the polymer material 2, thereby affecting the overall stability of the absorbent core. If the retention length of the low-melting point fibers and the plant fibers is greater than 30 mm, the excessive length will cause them to excessively lock the polymer material 2, hindering water absorption and expansion of the polymer material 2, thereby affecting the absorptive capacity of the absorbent core. The relative content of the low-melting-point fiber in the mixed fiber 3 is 10-40%, which can ensure its pulling force on the polymer material 2 and the strength of the absorbent core, while not occupying too much space of the polymer material 2, thereby ensuring the capacity of the polymer material 2 and determining the water absorption capacity of the absorbent core.

[0045] The pre-processing in step S1 comprises the following steps:

[0046] Step a1: The low-melting point fibers and plant fibers are loosened by a coarse loosening device 10 and stored in a fiber storage tank 11; wherein, the coarse loosening is performed by a coarse loosening mechanical device, such as a loosening roller with punching needles with large spacing, and the punching needles are used to loosen the large clumps of low-melting point fibers and the plant fibers into small clumps, which is convenient for subsequent loosening, mixing and transportation.

[0047] Step a2: The low-melting point fiber and the plant fiber are captured in the fiber storage tank 11 by a fine loosening device 12 and then transferred to a crusher 13 for mixing into a mixed fiber 3 having a relative low-melting point fiber content of 10-40%. After mixing, the mixed fiber 3 is conveyed to a mixing device 17 via a feeding blower 14. The fine loosening is performed by a fine loosening mechanical device, such as a loosening roller with closely spaced punching needles, which fully loosen the low-melting point fiber and the plant fiber, which have been lumped into small balls, into a fibrous shape, facilitating subsequent mixing of the two.

[0048] The post-mixing air-laying in step S1 comprises the following steps:

[0049] Step b1: The mixed fibers enter the mixing device 17 from the upper air chamber 18 at the upper end of the mixing device 17 , are broken up by the first roller group 19 of the mixing device 17 , and then fall into the polymer mixing chamber 20 of the mixing device 17 ;

[0050] Step b2: The polymer material 2 enters the polymer mixing chamber 20 through the polymer feeding group 26 of the mixing device 17 and is mixed with the low-melting-point fiber and the plant fiber, and is then mixed and broken up by the second roller group 21 to form a core mixed material; wherein, after the low-melting-point fiber and the plant fiber are mixed, they enter the mixing device 17 from the upper air chamber 18 at the upper end of the mixing device 17 through the feeding device under the action of the feeding fan 14, and the mixed fiber 3 of the low-melting-point fiber and the plant fiber is further broken up and combed by the first roller group 19 to facilitate subsequent mixing with the polymer material 2. At the same time, the broken fibers can be more intricate, thereby improving the locking ability of the mixed fiber 3 to the polymer material 2 and improving the stability of the overall structure.

[0051] Step b3: The core mixed material is broken up and mixed and then falls into the negative pressure air chamber 22 of the mixing device 17.

[0052] The downward negative pressure wind evenly falls on the forming mesh belt 24 covered with the composite bottom layer 4 to form a composite body. The core mixed material, under the action of the negative pressure wind cavity 23, evenly falls on the forming mesh belt 24 and combines with the composite bottom layer 4 laid on the forming mesh belt 24 to form the composite body. The negative pressure wind cavity 23 creates a downward negative pressure on the surface of the forming mesh belt 24 through the negative pressure device 16, causing the core mixed material to fall evenly on the forming mesh belt 24 after being dispersed and mixed by the second roller group 21. The composite bottom layer 4 is a non-woven fabric.

[0053] Step S2: After the composite comes out of the mixing device 17, it enters the oven 5 for drying until the relative moisture content of the composite is 6-10%, and then passes through the cooling device 8 to cool and set;

[0054] Step S3: The dried and cooled composite is then coated with polymer material 6, which is then sprayed with glue 7 and pressed together with the surface layer 1 via a pressing roller 9 to form an absorbent core. Spreading the polymer material 2 on the composite surface improves the water absorption capacity between the composite and the surface layer 1, allowing the surface layer 1 to quickly absorb liquid, resulting in a drier and more comfortable overall appearance. The surface layer 1 may be any nonwoven fabric except a hot air nonwoven fabric.

[0055] Step S4: The absorbent core is rolled up by a winding roller.

[0056] As a further technical solution of the present invention, the temperature of the oven 5 in step S3 is 110-140° C., and the distance between the upper pressing roller 9 and the lower pressing roller 9 in step S3 is adjustable.

[0057] After drying, the composite's moisture content is less than 10%, meeting national industry standards. The polymer material 2 is then spread on its surface to increase its content. Simultaneously, the adhesive 7 and the surface layer 1 are heat-pressed by a roller 9 to form the absorbent core. Spreading the polymer material 2 between the surface layer 1 and the composite improves the absorbent core's surface absorption efficiency and overall water absorption. The absorbent core is finally wound up by a winding roller for later use.

[0058] It should be noted that the present invention mixes the low-melting point fiber and the plant fiber, and uses them to mix with the polymer material 2. The gaps between the mixed fibers 3 wrap the polymer material 2, thereby fixing the polymer material 2 and stabilizing the structure. This is different from the traditional core structure. The traditional core structure is mostly achieved by digging holes in a thick accommodating layer to accommodate the polymer material 2. The accommodating layer occupies a large space, affecting the capacity and fluffiness of the polymer material 2. At the same time, the hardness of the accommodating layer is relatively large. The present invention locks the polymer material 2 by the mixed fiber 3, which can reduce the volume occupied by the stable structure, can accommodate more of the polymer material 2, and improve the absorption capacity of the absorbent core. At the same time, the mixed fiber 3 can ensure the stability of the overall structure while improving the overall softness, making it more comfortable to use.

[0059] Example 2 of the manufacturing process of the absorbent core:

[0060] like Figures 1 to 2 As shown, a manufacturing process of a diaper absorbent core with a fluffy fiber component is basically the same as that of Example 1. In addition to being a single non-woven fabric, the composite layer used in step S1 can be formed by pre-spreading mixed fibers 3 on the basis of the non-woven fabric to form a diffusion layer, so that after the fecal fluid is absorbed, it diffuses toward the surrounding areas along the bottom layer 4 of the absorbent core with the absorption point as the center through the diffusion layer formed by the mixed fibers 3, thereby improving the absorption efficiency and diffusion efficiency of the absorbent core. The manufacturing steps of the composite bottom layer 4 include:

[0061] Step c1: The pre-treated low-melting point fibers and plant fibers with a fiber length of 8-30 mm are fed into the mixing device 17 from the upper air chamber 18 at the upper end of the mixing device 17 , are broken up by the first roller group 19 of the mixing device 17 , and then fall into the polymer mixing chamber 20 of the mixing device 17 ;

[0062] Step c2: The second roller group 21 mixes and breaks up the mixture, and then falls into the negative pressure air chamber 22 of the mixing device 17. The downward negative pressure wind force evenly falls on the forming mesh belt 24 covered with the bottom layer 4 to form a composite bottom layer 4.

[0063] Among them, the low-melting point fiber and the plant fiber of the same fiber length are fluffed and mixed after the pretreatment of step S1, and the mixed fiber 3 with a low-melting point fiber content of 10-40% is formed. After further fluffing and mixing by the first roller group 19 and the second roller group 21 of the mixing device 17, it falls evenly onto the bottom layer 4 on the forming mesh belt 24 under the action of negative pressure, and is preliminarily compounded with the bottom layer 4 to form a composite bottom layer 4. The composite bottom layer 4 includes the bottom layer 4 and the mixed fiber 3 layers. The bottom layer 4 and the surface layer 1 can make the overall structure integrated. The mixed fiber 3 layers can make the fecal fluid diffuse and absorb rapidly in all directions above the bottom layer 4, and the fiber filaments formed by the upper end surface of the mixed fiber 3 can better connect with the core mixed material, making the overall structure more stable.

[0064] Example 1 of a mixing device for the raw materials of the absorbent core:

[0065] like Figures 1 to 6 As shown, a mixing device for raw materials of an absorbent core comprises a mixing device 17 and a feeding device and a negative pressure device 16 connected thereto, wherein the mixing device 17 comprises an upper air chamber 18, a first roller group 19, a polymer mixing chamber 20, a second roller group 21, a negative pressure air chamber 22, a negative pressure lower air chamber 23 and a forming mesh belt 24 arranged between the negative pressure air chamber 22 and the negative pressure lower air chamber 23, the upper end portion of the upper air chamber 18 is provided with a ventilation top cover 25 connecting the inside and outside of the mixing device 17, at least one fiber feed port is provided on the side wall of the upper air chamber 18 and is connected to the feeding device, and at least one fiber feed port is provided between the upper air chamber 18 and the polymer mixing chamber 20. A first roller group 19 is provided, wherein the first roller group 19 includes at least two breaking rollers, and at least one polymer feed port connected to the outside is provided on the side wall of the polymer mixing chamber 20, and the polymer feed port connects the polymer mixing chamber 20 and the polymer feed group 26. At least one second roller group 21 is provided between the negative pressure air chamber 22 and the polymer mixing chamber 20, and the second roller group 21 includes at least four breaking rollers. The forming mesh belt 24 is arranged around the negative pressure lower air chamber 23, and the lower end of the negative pressure lower air chamber 23 is provided with a mesh belt correction device 27 connected to the forming mesh belt 24, and the negative pressure lower air chamber 23 is provided with a negative pressure air port connected to the negative pressure device 16.

[0066] The mixing device 17 is connected to a cavity connected from top to bottom, and cooperates with the negative pressure device 16 to form a negative pressure mixing and molding cavity with downward suction. The airflow can move the fibers and other materials downward, and then the first roller group 19 and the second roller group 21 can evenly disperse and mix them, improving the degree of mixing. Under the action of suction and gravity, the mixed material is evenly adsorbed onto the forming mesh belt 24 to form a composite core. The entire process can highly mix the materials, and the natural downward movement can save production costs. The combined process is simple and convenient. The mixing device 17 can comb and disperse the fibers and other materials through the first roller group 19, improve the gaps and connectivity between the materials, and facilitate mixing with the subsequent polymer material 2, so that the polymer material 2 can smoothly and evenly enter the gaps between the fibers, thereby locking the polymer material. After mixing, it is further mixed and dispersed by the second roller group 21, so that it can evenly fall onto the composite base layer 4, preventing the mixed fibers 3 and polymer from piling up on the forming mesh belt 24 due to gravity.

[0067] As a further technical solution of the present invention, the feeding device includes a crusher 13, a feeding pipe 15 connecting the crusher 13 and the fiber feeding port, and a feeding fan 14 provided at the lower end of the feeding pipe 15. The feeding device is used for the pretreatment of step S1, mixing the low-melting-point fiber and the plant fiber.

[0068] As a further technical solution of the present invention, the beating roller includes a cotton stirring roller 28, vertical seat bearings 29 provided at both ends of the cotton stirring roller 28 for fixation, and a number of cotton stirring needles 30 evenly arranged around the circumference of the cotton stirring roller 28. A pressure plate 31 is provided at the connection between the cotton stirring needles 30 and the cotton stirring roller 28, and sealing plates 32 are also provided at both ends of the cotton stirring roller 28.

[0069] As a further technical solution of the present invention, the length of the stirring needles 30 of the first roller group 19 is greater than the length of the stirring needles 30 of the second roller group 21 .

[0070] The first roller group 19 and the second roller group 21 have the same working principle. Both are installed in the mixing device 17 through the vertical seat bearing 29. The stirring roller 28 is rotated to drive the stirring needle 30 to break up the mixed fiber 3 and mix the mixed fiber 3 with the polymer material 2. The difference is that the stirring needle 30 of the first roller group 19 is longer than the stirring needle 30 of the second roller group 21, so that the first roller group 19 is used for breaking up and the second roller group 21 is used for breaking up and mixing. The sealing plate 32 is used to prevent fibers from entering the rotating part of the stirring roller 28, which affects the service life of the mixing device 17.

[0071] Example 2 of a mixing device for the raw materials of the absorbent core:

[0072] like Figures 1 to 6 As shown, a mixing device for raw materials of an absorbent core has the same operating principle as the mixing device of embodiment 1, with the difference being that the first roller set 19 and the second roller set 21 of the mixing device 17 can have multiple layers of the dispersing rollers. For example, the first roller set 19 can have two layers of vertically distributed dispersing rollers, so that the limited mixing and dispersing can be carried out in different directions, resulting in more complete and uniform dispersing and mixing.

[0073] The above description is only a preferred embodiment of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and modifications without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A process for producing a diaper absorbent core with a fluffy fiber component, characterized in that: include: Step S1: low-melting-point fibers with a fiber length of 8-30 mm and plant fibers with a fiber length of 8-30 mm are pretreated to form mixed fibers with a relative content of low-melting-point fibers of 10-40%, the mixed fibers are added together with a polymer material into a mixing device, and after mixing, air-laid to form a composite; Step S2: After the composite comes out of the mixing device, it enters the oven for drying until the relative moisture content of the composite is 6-10%, and then passes through a cooling device to cool and set; Step S3: Sprinkling polymer material on the surface of the dried composite, spraying glue on the surface and laminating the surface layer with a pressing roller to form an absorbent core; Step S4: the absorbent core is rolled up by a rolling roller; The mixing device is connected to a feeding device and a negative pressure device, and the mixing device includes an upper air chamber, a first roller group, a polymer mixing chamber, a second roller group, a negative pressure air chamber, a negative pressure lower air chamber, and a forming mesh belt arranged between the negative pressure air chamber and the negative pressure lower air chamber. The upper end of the upper air chamber is provided with a ventilation top cover connecting the inside and outside of the mixing device, at least one fiber feed port is provided on the side wall of the upper air chamber and is connected to the feeding device, at least one first roller group is provided between the upper air chamber and the polymer mixing chamber, and the first roller group At least two breaking rollers are included, at least one polymer feed port connected to the outside is provided on the side wall of the polymer mixing chamber, the polymer feed port is connected to the polymer mixing chamber and the polymer feed group, at least one second roller group is provided between the negative pressure air chamber and the polymer mixing chamber, the second roller group includes at least four breaking rollers, the forming mesh belt is arranged around the negative pressure lower air chamber, the lower end of the negative pressure lower air chamber is provided with a mesh belt correction device connected to the forming mesh belt, and the negative pressure lower air chamber is provided with a negative pressure air port connected to the negative pressure device; The post-mixing air-laying in step S1 comprises the following steps: Step b1: the mixed fibers enter the mixing device from the upper air chamber at the upper end of the mixing device, are broken up by the first roller group of the mixing device, and then fall into the polymer mixing chamber of the mixing device; Step b2: The polymer material enters the polymer mixing chamber through the polymer feeding group of the mixing equipment and is mixed with the low-melting-point fiber and the plant fiber, and then is mixed and broken up by the second roller group to form a core mixed material; Step b3: the core mixed material is dispersed and mixed and then falls into the negative pressure air cavity of the mixing equipment, and is evenly dropped onto the forming mesh belt covered with the composite bottom layer by the downward negative pressure wind force to form a composite body.

2. The process for producing a diaper absorbent core having a fluffy fiber component according to claim 1, characterized in that: The pre-processing in step S1 comprises the following steps: Step a1: the low-melting-point fibers with a fiber length of 8-30 mm and the plant fibers with a fiber length of 8-30 mm are both loosened by a coarse loosening device and stored in a fiber storage tank; Step a2: The low-melting point fiber and plant fiber are taken from the fiber storage tank by a fine loosening device and mixed into a crusher to form a mixed fiber with a relative content of low-melting point fiber of 10-40%. After mixing, the mixed fiber is transported to the mixing equipment via a feeding fan.

3. The process for producing a diaper absorbent core having a fluffy fiber component according to claim 1, characterized in that: The manufacturing process of the composite bottom layer in step b3 comprises the following steps: Step c1: The pretreated low-melting point fibers and the plant fibers with a fiber length of 8-30 mm are fed into the mixing device from the upper air chamber at the upper end of the mixing device, are broken up by the first roller group of the mixing device, and then fall into the polymer mixing chamber of the mixing device; Step c2: The second roller group mixes and breaks up the mixture, and then falls into the negative pressure air chamber of the mixing equipment. The downward negative pressure wind force evenly falls on the forming mesh belt covered with the bottom layer to form a composite bottom layer.

4. The process for producing a diaper absorbent core having a fluffy fiber component according to claim 1, characterized in that: The oven temperature in step S3 is 110-140° C., and the distance between the upper pressing roller and the lower pressing roller in step S3 is adjustable.

5. The process for producing a diaper absorbent core with fluffy fiber components according to claim 1, characterized in that: The feeding device comprises a crusher, a feeding pipe connecting the crusher and the fiber feeding port, and a feeding fan arranged at the lower end of the feeding pipe.

6. The process for producing a diaper absorbent core having a fluffy fiber component according to claim 1, characterized in that: The beating roller includes a mixing roller, vertical seat bearings provided at both ends of the mixing roller for fixation, and a number of mixing needles evenly arranged around the circumference of the mixing roller. A pressure plate is provided at the connection between the mixing needles and the mixing roller, and sealing plates are also provided at both ends of the mixing roller.

7. The process for producing a diaper absorbent core having a fluffy fiber component according to claim 6, characterized in that: The length of the cotton stirring needles of the first roller group is greater than the length of the cotton stirring needles of the second roller group.

8. The process for producing a diaper absorbent core having a fluffy fiber component according to claim 6, characterized in that: When the number of the first roller groups and the second roller groups is greater than two, the first roller groups are arranged perpendicular to each other, and the second roller groups are arranged perpendicular to each other.

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