Absorbing core and preparation method and application thereof

Abstract

The invention relates to the technical field of absorption cores, in particular to an absorption core and a preparation method and application thereof. The invention discloses an absorption core body. The absorption core body comprises a plurality of upper layers and lower layers, wherein the upper layers are sequentially attached together from top to bottom, and the lower layers are attached to the lower portions of the upper layers. The upper layer is a wood pulp layer made of 100% fluff pulp or the upper layer is needle-punched cloth; and the lower layer is spunlace cloth or dust-free paper. The absorption core body comprises the upper layer and the lower layer, the upper layer is fluffy and soft, and liquid can be rapidly transmitted to the lower layer; the lower layer is compact and not prone to deformation, liquid can be rapidly and transversely conducted, the liquid can be stored, reverse osmosis to the upper layer is not prone to occurring, meanwhile, larger strength can be provided for the core body, and the core body is not prone to breakage.

Description

Technical Field

[0001] The present invention relates to the technical field of absorbent cores, and in particular to an absorbent core and a preparation method and application thereof. Background Art

[0002] Almost all the absorbent cores of personal care absorbent products on the market, whether traditional wood pulp cores or composite cores, contain super absorbent resins. Although super absorbent resins can bring better pure water absorption capacity to products, they also have the following series of problems and disadvantages:

[0003] After absorbing liquid, the highly absorbent resin will produce gel blockage, making it difficult for the liquid to diffuse in the product, and the core utilization rate is low; the ability to absorb liquids such as menstrual blood is not ideal; it is not easy to degrade and is environmentally friendly, etc.; for example, a common liquid sanitary napkin product, its core uses FlexFoam liquid absorption material and does not contain highly absorbent resin, but the product absorbs liquid slowly, the core is not soft and fit enough, and the core material is not easy to degrade and is environmentally friendly. Summary of the invention

[0004] The present application provides an absorbent core and a preparation method and application thereof. The absorbent core comprises an upper layer and a lower layer. The upper layer is fluffy and soft, and can quickly transfer liquid to the lower layer. The lower layer is dense and not easily deformed, so that the liquid can be quickly transversely conducted and can store liquid, and is not easy to reversely seep to the upper layer. At the same time, it can provide greater strength for the core, making it not easy to break.

[0005] The technical solution adopted by this application to solve its technical problem is:

[0006] In a first aspect, the present application provides an absorbent core, comprising a plurality of upper layers attached together in sequence from top to bottom and a lower layer attached and arranged below the upper layers;

[0007] The upper layer is a wood pulp layer made of 100% fluff pulp or a needle-punched cloth;

[0008] The lower layer is spunlace cloth or dust-free paper.

[0009] In one or more technical solutions, a surface of the lower layer away from the upper layer is a water-repellent surface.

[0010] In one or more technical solutions, the method for preparing the wood pulp layer comprises the following steps:

[0011] The wood pulp fibers are separated by a pulp board crusher, processed by a quantitative device and a forming hub, and demolded to form a wood pulp layer; the wood pulp layer is made of 100% fluff pulp, the fluff pulp has a gram weight of 1-5g, and a quantitative weight of 80-160g / m 2 , the thickness of the wood pulp layer is controlled at 1.5-3.0mm.

[0012] In one or more technical solutions, the method for preparing the needle-punched cloth comprises the following steps:

[0013] The absorbent cotton fibers are fully and evenly mixed, opened and impurity removed, and then combed into two layers of fiber webs by a carding machine. The two layers of fiber webs are needle-punched and reinforced by a needle-punched machine to form a needle-punched cloth to obtain the upper layer of the absorbent core;

[0014] The single layer of the two-layer fiber web has a grammage of 40-80 gsm; the grammage of the needle-punched cloth is 80-150 gsm, and the thickness of the needle-punched cloth is controlled between 1.5-3.0 mm.

[0015] In one or more technical solutions, the method for preparing the spunlace fabric comprises the following steps:

[0016] a11) Manufacturing of pure cotton spunlace fabric

[0017] The cotton fibers of different lengths are fully and evenly mixed, wherein the proportion of short fibers is 60%-90%; after loosening and removing impurities, the impurities in the fibers are removed, and the fibers are further mixed; the fibers are combed into a single-layer web with a grammage of 20-40gsm by a carding machine, and the two layers of webs are combined and drafted and transferred to the spunlace machine; the grey fabric is formed after pre-spunlace and positive and negative spunlace, and the spunlace pressures are: 70bar, 90bar, 90bar, 110bar and 110bar respectively; the spunlace drafting rates are 110%, 105%, 105%, 103% and 103%;

[0018] b11) Degreasing and bleaching of spunlace grey fabric

[0019] The spunlace grey fabric is rolled up by the equipment and transferred to the de-bleaching pot, where it undergoes pre-washing, boiling and bleaching, re-bleaching, washing and neutralization treatments;

[0020] The pre-washing uses a refining agent, the temperature is set at 60°C, and the time is set to 30 minutes; the bleaching uses caustic soda, refining agent, hydrogen peroxide, and stabilizer, the temperature is set to 115°C, and the time is set to 90 minutes;

[0021] The rebleaching process uses caustic soda, refining agent, hydrogen peroxide, and stabilizer, with the temperature set at 110°C and the time set at 90 minutes; the water washing and neutralization treatment uses hot water for two washes, normal temperature water for two washes, and the last wash is a citric acid solution;

[0022] c11) Finishing of bleached cloth rolls

[0023] The washed and neutralized cloth rolls are dried and subjected to single-sided water-repellent finishing;

[0024] Drying is carried out in an oven or drying drum, the temperature is controlled at 102-110℃, and the drying time is 0.5h; the single-sided water-repellent finishing can be online spraying, transfer printing or coating finishing agent;

[0025] d11) Cutting and packaging

[0026] The spunlace cotton fabric rolls after single-sided water-repellent finishing are cut and packaged, and the width is 17-18cm.

[0027] In one or more technical solutions, the method for preparing the spunlace fabric comprises the following steps:

[0028] a21) Viscose spunlace fabric manufacturing

[0029] The viscose fibers are fully dispersed and mixed, and then combed into a single-layer fiber web with a grammage of 20-40gsm by a carding machine; the two layers of fiber web and the interlayer wood pulp layer with a grammage of 10-20gsm are combined and transferred to the spunlace machine; the grey cloth is formed after pre-spunlacement, positive and negative spunlacement, and the spunlacement pressures are 70bar, 90bar, 90bar, 110bar and 110bar respectively; the spunlacement drafting rates are 110%, 105%, 105%, 103% and 103%;

[0030] b21) Grey fabric finishing

[0031] The fabric roll after spunlaced is dried and subjected to single-sided water-repellent finishing. The drying process uses an oven or a drying drum, the temperature is controlled at 102-110°C, and the drying time is 0.5h. The single-sided water-repellent finishing can be online spraying, transfer printing or coating finishing agent;

[0032] c21) Cutting and packaging

[0033] The cloth rolls after single-sided water-repellent finishing are cut and packaged, and the width is 17-18cm.

[0034] In one or more technical solutions, the method for preparing the dust-free paper comprises the following steps:

[0035] a31) Manufacturing of dust-free paper fabrics

[0036] Hot melt fibers are mixed into wood pulp fibers, wherein the proportion of hot melt fibers is 15%-20%. After being air-laid, the low melting point fibers in the web are melted by hot air or hot rolling to reinforce the web into a grey cloth; wherein the weight of the grey cloth is 40-100gsm, and the thickness is controlled between 0.6-1.5mm;

[0037] b31) Grey fabric finishing

[0038] The grey cloth is rolled and subjected to single-sided water-repellent finishing, which can be an online spraying, transfer or coating finishing agent.

[0039] In one or more technical solutions, the mass concentration of the finishing agent is 6%-10%.

[0040] In a second aspect, the present application provides a method for preparing an absorbent core as described in the first aspect, comprising the following steps:

[0041] S1. Preparation of the upper layer

[0042] A wood pulp layer or needle punched cloth made of 100% fluff pulp is used as the upper layer;

[0043] S2. Preparation of the lower layer

[0044] Use spunlace cloth or dust-free paper as the bottom layer;

[0045] S3. Core composite

[0046] The upper and lower layers of materials are placed on the unwinding device, wherein the lower layer is ensured to have its water-repellent surface at the bottom; the upper and lower layers are attached together by hot melt adhesive.

[0047] In a third aspect, the present application provides an application of an absorbent core, wherein the absorbent core described in the first aspect or the absorbent core manufactured by the preparation method described in the second aspect is applied to an absorbent product.

[0048] In one or more technical solutions, the absorbent product includes sanitary napkins, menstrual pants, and diapers.

[0049] The beneficial effects of this application are:

[0050] 1. The absorbent core described in the present application adopts natural, environmentally friendly and degradable materials for the upper and lower layers to replace the highly absorbent resin, such as 100% cotton spunlace cloth, absorbent backing paper, etc. These materials are not only environmentally friendly but also have good absorption performance.

[0051] 2. The absorbent core described in the present application is formed into a multi-layer structure by scientifically matching materials with different characteristics. Specifically, the upper layer is responsible for rapid absorption and transfer of liquid, while the lower layer is responsible for storage and transverse conduction of liquid, while providing strength and stability of the core. This structural design of the absorbent core effectively solves the problems of poor liquid diffusion and low core utilization.

[0052] 3. The absorbent core described in this application undergoes fine processing of raw materials during the production process, such as degreasing and bleaching, drying, and water-repellent finishing, so as to improve the absorption performance and stability of the materials. At the same time, hot melt adhesive is used to bond the various layers of materials to ensure the integrity and durability of the core.

[0053] 4. The absorbent core described in the present application has a multi-layer structure with optimized design and scientific material matching, so that the absorbent core of the present invention has better softness and comfort while maintaining high absorption performance, thereby improving user experience. In addition, the core also has good anti-reverse osmosis performance and environmental protection, meeting the needs of modern personal care products. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0055] Figure 1 This is a schematic diagram of the structure of an absorbent core according to the present application containing a single upper layer;

[0056] Figure 2 This is a schematic diagram of the structure of an absorbent core according to the present application having two upper layers;

[0057] Among them: 1. upper layer; 2. lower layer; 3. hot melt adhesive. DETAILED DESCRIPTION

[0058] In order to facilitate the understanding of those skilled in the art, the present invention is further described below in conjunction with embodiments, and the contents mentioned in the implementation modes are not intended to limit the present invention.

[0059] As used herein, "and / or" includes the term of any and all combinations of one or more associated listed items. The terms used herein are only used to describe specific embodiments and are not intended to limit the present invention. As used herein, the singular forms "a", "an", "an" and "the" are also intended to include the plural forms, unless the context clearly indicates otherwise. It is further understood that "including", when used in this specification, specifies the stated features, integers, steps, operations, elements and / or compositions, but does not exclude the existence or addition of one or more other features, integers, steps, operations, elements, compositions and / or combinations thereof.

[0060] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention belongs. It is further understood that terms, such as defined in commonly used dictionaries, are interpreted in accordance with their meanings in the context of the relevant art and are not in an idealized or overly formal sense unless explicitly so defined herein.

[0061] The exemplary invention described herein may appropriately lack any one or more element limitations that are not specifically disclosed herein. Therefore, the terms "comprise", "include", "contain", etc. should be understood broadly and non-restrictively. In addition, the terminology used herein is used as a description, not a limitation, and it is unintentional to use these terminology expressions that do not include any equivalent characteristics, but only describe some of their characteristics, but various modifications are possible within the scope of the present invention according to the rights. Therefore, although the present invention has been specifically disclosed by preferred embodiments and optional features, the modifications disclosed herein to embody the changes of the present invention may be recorded by those skilled in the art, and such modifications and changes will be considered to be within the scope of the present invention.

[0062] In order to solve the problems of low core utilization rate of conventional absorbent products, insufficient softness and fit of the products, and difficulty in material degradation and environmental protection, the present application provides the following Figure 1-2 An absorbent core as shown, Figure 1-2 An absorbent core shown includes a plurality of upper layers 1 adhered together in sequence from top to bottom and a lower layer 2 adhered below the lowermost upper layer; the upper layer and the lower layer are adhered by hot melt adhesive 3.

[0063] The side of the lower layer away from the upper layer is a water-repellent surface; the water-repellent surface is 100% water-repellent.

[0064] The upper layer is a wood pulp layer made of 100% fluff pulp or a needle-punched cloth;

[0065] The lower layer is spunlace cloth or dust-free paper.

[0066] It can be understood that, specifically, the main function of the water-repellent surface is to prevent the liquid that has been absorbed through the upper and lower layers from leaking further downward, ensuring that the liquid is effectively locked inside the core, thereby keeping the product dry and clean. By providing a waterproof surface, the overall performance of the absorbent product can be further improved, including absorption speed, absorption volume, and liquid retention capacity. The waterproof surface can effectively reduce the reverse osmosis of the liquid, allowing the product to continue to maintain an efficient absorption state during use.

[0067] It can be understood that by using a wood pulp layer or needle-punched cloth made of 100% fluff pulp as the upper layer, the upper layer has the characteristics of being fluffy and soft, and can quickly transfer liquid to the lower layer.

[0068] By using spunlace cloth or dust-free paper as the lower layer; the lower layer is dense and not easy to deform, so that the liquid can be quickly conducted laterally and can store the liquid, and it is not easy to seep back to the surface layer. At the same time, it can provide greater strength for the core, making it not easy to break.

[0069] At the same time, the water-repellent surface can significantly improve the user experience. It avoids external contamination and discomfort caused by liquid leakage, making users more comfortable and at ease during use.

[0070] Specifically, the upper layer may include one upper layer or two upper layers 1 attached together by hot melt adhesive 3 ; or three or more upper layers attached together by hot melt adhesive 3 .

[0071] In one or more embodiments, the upper layer is made of 100% fluff pulp or a needle-punched cloth.

[0072] Specifically, the method for preparing the wood pulp layer comprises the following steps:

[0073] The wood pulp fibers are separated by a pulp board crusher, processed by a quantitative device and a forming hub, and demolded to form a wood pulp layer; the wood pulp layer is made of 100% fluff pulp, the fluff pulp has a gram weight of 1-5g, and a quantitative weight of 80-160g / m 2 , the thickness of the wood pulp layer is controlled at 1.5-3.0mm.

[0074] Therefore, the present application adopts fluff pulp as the upper layer; because fluff pulp has good absorbency and liquid retention, it can quickly absorb and lock liquid, reduce the diffusion and leakage of liquid in the core, and thus improve the overall utilization rate of the core; at the same time, the fluff pulp is designed in a specific thickness range (1.5-3.0mm), which not only ensures sufficient absorption capacity, but also avoids material waste caused by excessive thickness and insufficient absorption caused by excessive thinness. At the same time, in terms of material selection, the fluff pulp itself has good softness and can provide a comfortable touch for the product.

[0075] Specifically, the method for preparing the needle-punched cloth comprises the following steps:

[0076] The absorbent cotton fibers are fully and evenly mixed, opened and impurity removed, and then combed into two layers of fiber webs by a carding machine. The two layers of fiber webs are needle-punched and reinforced by a needle-punched machine to form a needle-punched cloth to obtain the upper layer of the absorbent core;

[0077] The single layer of the two-layer fiber web has a grammage of 40-80 gsm; the grammage of the needle-punched cloth is 80-150 gsm, and the thickness of the needle-punched cloth is controlled between 1.5-3.0 mm.

[0078] It is understandable that when needle-punched cloth is used as the upper layer, cotton fiber is used as the raw material. Cotton fiber, with its natural skin-friendliness and softness, further enhances the softness and comfort of the product. Both fluff pulp and cotton fiber come from natural plants and are renewable resources. Compared with some synthetic materials, they have less impact on the environment during production and use.

[0079] In one or more technical solutions, the lower layer is made of spunlace cloth or dust-free paper.

[0080] Specifically, the method for preparing the spunlace fabric comprises the following steps:

[0081] a11) Manufacturing of pure cotton spunlace fabric

[0082] The cotton fibers of different lengths are fully and evenly mixed, wherein the proportion of short fibers is 60%-90%; after loosening and removing impurities, the impurities in the fibers are removed, and the fibers are further mixed; the fibers are combed into a single-layer web with a grammage of 20-40gsm by a carding machine, and the two layers of webs are combined and drafted and transferred to the spunlace machine; the grey fabric is formed after pre-spunlace and positive and negative spunlace, and the spunlace pressures are: 70bar, 90bar, 90bar, 110bar and 110bar respectively; the spunlace drafting rates are 110%, 105%, 105%, 103% and 103%;

[0083] b11) Degreasing and bleaching of spunlace grey fabric

[0084] The spunlace grey fabric is rolled up by the equipment and transferred to the de-bleaching pot, where it undergoes pre-washing, boiling and bleaching, re-bleaching, washing and neutralization treatments;

[0085] The pre-washing uses a refining agent, the temperature is set at 60°C, and the time is set to 30 minutes; the bleaching uses caustic soda, refining agent, hydrogen peroxide, and stabilizer, the temperature is set to 115°C, and the time is set to 90 minutes;

[0086] The rebleaching process uses caustic soda, refining agent, hydrogen peroxide, and stabilizer, with the temperature set at 110°C and the time set at 90 minutes; the water washing and neutralization treatment uses hot water for two washes, normal temperature water for two washes, and the last wash is a citric acid solution;

[0087] c11) Finishing of bleached cloth rolls

[0088] The washed and neutralized cloth rolls are dried and subjected to single-sided water-repellent finishing;

[0089] Drying is carried out in an oven or drying drum, the temperature is controlled at 102-110°C, and the drying time is 0.5h; the single-sided water-repellent finishing can be online spraying, transfer printing or coating finishing agent, and the mass concentration of the finishing agent is 6%-10%;

[0090] d11) Cutting and packaging

[0091] The spunlace cotton fabric rolls after single-sided water-repellent finishing are cut and packaged, and the width is 17-18cm.

[0092] Alternatively, a method for preparing a spunlace fabric comprises the following steps:

[0093] a21) Viscose spunlace fabric manufacturing

[0094] The viscose fibers are fully dispersed and mixed, and then combed into a single-layer fiber web with a grammage of 20-40gsm by a carding machine; the two layers of fiber web and the interlayer wood pulp layer with a grammage of 10-20gsm are combined and transferred to the spunlace machine; the grey cloth is formed after pre-spunlacement, positive and negative spunlacement, and the spunlacement pressures are 70bar, 90bar, 90bar, 110bar and 110bar respectively; the spunlacement drafting rates are 110%, 105%, 105%, 103% and 103%;

[0095] b21) Grey fabric finishing

[0096] The spunlaced fabric roll is dried and subjected to single-sided water-repellent finishing. The drying process uses an oven or a drying drum, the temperature is controlled at 102-110°C, and the drying time is 0.5h. The single-sided water-repellent finishing can be an online spraying, transfer or coating finishing agent, and the mass concentration of the finishing agent is 6%-10%;

[0097] c21) Cutting and packaging

[0098] The cloth rolls after single-sided water-repellent finishing are cut and packaged, and the width is 17-18cm.

[0099] Specifically, the method for preparing dust-free paper comprises the following steps:

[0100] a31) Manufacturing of dust-free paper fabrics

[0101] Hot melt fibers are mixed into wood pulp fibers, wherein the proportion of hot melt fibers is 15%-20%. After being air-laid, the low melting point fibers in the web are melted by hot air or hot rolling to reinforce the web into a grey cloth; wherein the weight of the grey cloth is 40-100gsm, and the thickness is controlled between 0.6-1.5mm;

[0102] b31) Grey fabric finishing

[0103] The grey cloth is rolled and subjected to single-side water-repellent finishing. The single-side water-repellent finishing can be an online spraying, transfer printing or coating finishing agent, and the mass concentration of the finishing agent is 6%-10%.

[0104] In one or more technical solutions, the mass concentration of the finishing agent is 6%-10%.

[0105] The method for preparing the absorbent core comprises the following steps:

[0106] S1. Preparation of the upper layer

[0107] A wood pulp layer made of 100% fluff pulp is used as the upper layer;

[0108] S2. Preparation of the lower layer

[0109] Using spunlace fabric as the bottom layer;

[0110] S3. Core composite

[0111] The upper and lower layers of materials are placed on the unwinding device, wherein the lower layer is ensured to have its water-repellent surface at the bottom; the upper and lower layers are attached together by hot melt adhesive.

[0112] The absorbent core manufactured by the preparation method described in the present application has a greatly improved core utilization rate compared to traditional products, and the liquid can quickly penetrate into the product after contacting it, and the material is easily degradable and environmentally friendly. The absorbent core has no significant difference in the saturated absorption capacity of artificial menstrual blood compared to traditional products containing highly absorbent resins.

[0113] Specifically, the absorbent core described in the present application can be applied to absorbent products; absorbent products include sanitary napkins, menstrual pants, and diapers.

[0114] In the following examples and comparative examples, the stabilizer is a fatty acid magnesium salt surfactant stabilizer; the refining agent used in the degreasing and bleaching process is a polyol refining agent or other common refining agents; the finishing agent used for water-repellent finishing is: XF-4001 from Daikin Fluorochemical (China) Co., Ltd.

[0115] Example 1

[0116] A method for preparing an absorbent core comprises the following steps:

[0117] S1. Preparation of the upper layer

[0118] Use needle punched cloth as the upper layer;

[0119] The absorbent cotton fibers of different lengths are fully and evenly mixed, and then loosened and impurities are removed from the fibers, and the fibers are further mixed evenly; they are combed into two layers of fiber webs by a carding machine, and the single layer weight is 50gsm. They are reinforced by needle punching by a needle punching machine to form needle punched cloth. The weight of the needle punched cloth material is controlled at 100gsm and the thickness is controlled at 1.9mm.

[0120] S2. Preparation of the lower layer

[0121] Using spunlace fabric as the bottom layer;

[0122] The method for preparing the spunlace fabric comprises the following steps:

[0123] a) Manufacturing of pure cotton spunlace grey fabric: Cotton fibers of different lengths (short fibers controlled at 23-28mm, long fibers controlled at 29mm-50mm) are fully and evenly mixed, with the proportion of short fibers at 60%; after loosening and removing impurities, impurities in the fibers are removed, and the fibers are further mixed; a single-layer fiber web with a grammage of 24.4gsm is formed by a carding machine, and the two layers of fiber webs are combined and drafted and transferred to the spunlace machine. After pre-spunlacement, positive and negative spunlacement, the grey fabric is formed, and the spunlacement pressures are: 70bar, 90bar, 90bar, 110bar and 110bar respectively; the spunlacement drafting rates are 110%, 105%, 105%, 103% and 103%.

[0124] b) Degreasing and bleaching of spunlace grey fabric: The spunlace grey fabric is rolled up by the equipment and transferred to the de-bleaching pot, and then pre-washed, boiled and bleached, re-bleached, and washed and neutralized. The pre-wash uses a refining agent (0.3g / L), the temperature is set at 60℃, and the time is set to 30min; the boiling and bleaching uses caustic soda (6.0g / L), a refining agent (2.5g / L), hydrogen peroxide (3.5g / L), and a hydrogen peroxide stabilizer (3.0g / L), the temperature is set at 115℃, and the time is set to 90min; the re-bleaching uses caustic soda (1.5g / L), a refining agent (1.0g / L), hydrogen peroxide (7.5g / L), and a hydrogen peroxide stabilizer (2.0g / L), the temperature is set at 110℃, and the time is set to 90min; the water washing and neutralization uses two hot water washes, two normal temperature water washes, and the last water washing and neutralization uses citric acid (0.4g / L).

[0125] c) Finishing of bleached cloth rolls: The bleached cloth rolls are dried and subjected to single-sided water-repellent finishing. The drying process uses an oven or a drying drum, the temperature is controlled at 102-110°C, and the drying time is 0.5h; the single-sided water-repellent finishing process can be online spraying, transfer printing or coating, wherein the finishing agent concentration is 6%, which achieves 100% water repellency on one side.

[0126] d) Slitting and packaging: The finished spunlace cotton fabric rolls are slit and packaged, and the width is controlled at 17-18cm.

[0127] S3. Core composite

[0128] Place the lower layer on the unwinding device to ensure that the water-repellent and waterproof surfaces of the lower layer are located on the lower layer. Pass through the glue spraying device to ensure that the hot melt adhesive is evenly sprayed on the upper part of the lower layer. The demoulded fluff pulp layer (upper layer) is conveyed to the upper part of the lower layer by the conveyor belt, and the lower layer is bonded and compounded by hot melt adhesive to obtain the absorbent core. In the absorbent core, the side of the lower layer away from the upper layer is the water-repellent and waterproof surface.

[0129] Sanitary napkin product preparation

[0130] The absorbent core is connected to the surface layer, the guide layer, and the leakproof edge by hot melt adhesive, and the material is cut and formed by a cutting die. The water-repellent and waterproof surfaces of the absorbent core are coated with backing glue and wing glue, and then covered with release paper and a small packaging film, and folded into a single sanitary napkin. It is packaged into a finished product by online packaging equipment.

[0131] Set up the experimental control group:

[0132] The absorbent core of the control group product is made of 0.4g of superabsorbent resin, 3.3g of fluff pulp and 20gsm toilet paper. It is matched with materials such as surface layer, guide layer, leakproof edge, leakproof bottom film, release paper and small envelope. The main difference between the control group and the product of Example 1 is the different absorbent core and the presence or absence of leakproof bottom film.

[0133] Test analysis:

[0134] Material testing: In the same laboratory and experimental conditions (temperature 23±1℃, humidity 50±5%RH), the thickness, gram weight and wicking height (10min) of the upper and lower layers were tested respectively. The test data are as follows:

[0135] Test items thickness Weight Wicking height (10min) unit mm <![CDATA[g / m 2 ]]> mm upper layer 1.9 100 88 Lower level 0.56 50 165

[0136] In the same laboratory and experimental conditions (temperature 23±1℃, humidity 50±5%RH), the absorption rate was tested using the GB / T8939-2018 standard, and other items were tested using the enterprise standard Q / QMSD 086-2024 standard. The test results are as follows:

[0137] Test items Absorption rate Reverse osmosis Artificial menstrual blood absorption Bottom diffusion length Bottom diffusion width unit s g g mm mm Control group 24 0.5 52 82 56 Example 1 19 0.4 46 125 70

[0138] Example 2

[0139] A method for preparing an absorbent core comprises the following steps:

[0140] S1. Preparation of the upper layer

[0141] A wood pulp layer made of 100% fluff pulp is used as the first upper layer;

[0142] Made of 100% fluff pulp, the wood pulp fibers are separated by a pulp board crusher, and then demolded and formed into the upper layer of the absorbent core through a quantitative device and a forming hub. The fluff pulp weight is controlled at 1-5g, and the quantitative is 100g / m 2 , its thickness is 1.8mm.

[0143] Use needle punched cloth as the second upper layer;

[0144] The absorbent cotton fibers are fully and evenly mixed, and then loosened and impurities are removed from the fibers, and the fibers are further mixed evenly; the fibers are combed into two layers of webs by a carding machine, and the single-layer weight is 40gsm. The two layers of single-layer webs are reinforced by needle punching by a needle punching machine to form needle-punched cloth. The weight of the needle-punched cloth material is controlled at 80gsm and the thickness is controlled at 1.5mm.

[0145] S2. Preparation of the lower layer

[0146] Using spunlace fabric as the bottom layer;

[0147] a) Viscose spunlace grey fabric production: The viscose fibers are fully dispersed and mixed, and then combed into a single-layer fiber web with a grammage of 30gsm through a carding machine. A wood pulp layer with a grammage of 19.5gsm is sandwiched between the two layers of fiber webs, and the three layers are combined and transferred to the spunlace machine. After pre-spunlacement, positive and negative spunlacement, the grey fabric is formed, and the spunlacement pressures are 70bar, 90bar, 90bar, 110bar and 110bar respectively; the spunlacement drafting rates are 110%, 105%, 105%, 103% and 103%.

[0148] b) Grey fabric finishing: The fabric roll after spunlace is dried and subjected to single-sided water repellent finishing. The drying process uses an oven or drying drum, the temperature is controlled at 102-110℃, and the drying time is 0.5h.

[0149] c) Slitting and packaging: The sorted cloth rolls are slit and packaged, and the width is controlled at 17-18cm.

[0150] S3. Core online compounding

[0151] The first upper layer, the second upper layer, and the lower layer are placed on the unwinding device, wherein the lower layer is ensured to have its water-repellent surface located at the lower layer. The hot melt adhesive is sprayed evenly on the second upper layer and the lower layer through the adhesive spraying device, and the first upper layer, the second upper layer, and the lower layer are bonded and laminated by the hot melt adhesive to obtain an absorbent core; Figure 2 As shown, in the absorbent core, the upper layer includes a first upper layer, a second upper layer, and the lower layer is a lower layer.

[0152] Sanitary napkin product preparation

[0153] The absorbent core is connected to the surface layer, the guide layer, the leakproof bottom film, and the leakproof partition edge by hot melt adhesive, and the material is cut and formed by a cutting die. The backing adhesive and the wing adhesive are scraped on the leakproof bottom film, and the release paper and the small packaging film are covered, and folded into a single sanitary napkin. It is packaged into a finished product by online packaging equipment.

[0154] Set up the experimental control group:

[0155] The absorbent core of the control group product is made of 0.4g of superabsorbent resin, 3.3g of fluff pulp and 20gsm toilet paper. It is matched with materials such as surface layer, guide layer, leakproof edge, leakproof bottom film, release paper and small envelope. The main difference between the control group and the product of Example 2 is the different absorbent core.

[0156] Test analysis:

[0157] Material testing: In the same laboratory and experimental conditions (temperature 23±1℃, humidity 50±5%RH), the thickness, gram weight and wicking height (10min) of the upper and lower layers were tested respectively. The test data are as follows:

[0158] Test items thickness Weight Wicking height (10min) unit mm <![CDATA[g / m 2 ]]> mm First upper level 1.8 100 63 Second upper floor 1.5 80 79 Lower level 0.8 80 145

[0159] In the same laboratory and experimental conditions (temperature 23±1℃, humidity 50±5%RH), the absorption rate was tested using the GB / T8939-2018 standard, and other items were tested using the enterprise standard Q / QMSD 086-2024 standard. The test results are as follows:

[0160] Test items Absorption rate Reverse osmosis Artificial menstrual blood absorption Bottom diffusion length Bottom diffusion width unit s g g mm mm Control group 24 0.5 52 82 56 Example 2 18 0.3 48 114 70

[0161] Example 3

[0162] A method for preparing an absorbent core comprises the following steps:

[0163] S1. Preparation of the upper layer

[0164] A wood pulp layer or needle punched cloth made of 100% fluff pulp is used as the upper layer;

[0165] The method for preparing the wood pulp layer comprises the following steps:

[0166] The wood pulp fibers are separated by a pulp board crusher, and then demolded and formed into the upper layer of the absorbent core after passing through a quantitative device and a forming hub. The weight of the fluff pulp is controlled at 1-5g, and the weight of the wood pulp layer is 150g / m 2 , its thickness is controlled at 2.6mm.

[0167] S2. Preparation of the lower layer

[0168] Use dust-free paper as the bottom layer;

[0169] The method for preparing dust-free paper comprises the following steps:

[0170] a) Manufacturing of dust-free paper fabric: Hot melt fibers are mixed into wood pulp fibers, where the proportion of hot melt fibers is 15%-20%. After being air-laid, the low melting point fibers in the web are melted by hot air or hot rolling to reinforce the web into cloth. The weight of the dust-free paper fabric is 79gsm and the thickness is controlled at 0.9mm.

[0171] b) Grey fabric finishing

[0172] The grey cloth is rolled and subjected to single-sided water-repellent finishing, and the single-sided water-repellent finishing process can be online spraying, transfer printing or coating, wherein the finishing agent concentration is 10%, which achieves 100% water repellency on one side.

[0173] S3. Core online compounding

[0174] Place the lower layer on the unwinding device to ensure that the water-repellent and waterproof surfaces of the lower layer are located on the lower layer. Pass through the glue spraying device to ensure that the hot melt adhesive is evenly sprayed on the upper part of the lower layer. The demoulded fluff pulp layer (upper layer) is conveyed to the upper part of the lower layer by the conveyor belt, and the lower layer is bonded and compounded by hot melt adhesive to obtain the absorbent core. In the absorbent core, the side of the lower layer away from the upper layer is the water-repellent and waterproof surface.

[0175] Sanitary napkin product preparation:

[0176] The whole core is connected with the surface layer, the guide layer, the leakproof edge and the leakproof bottom film by hot melt adhesive, and the materials are cut and formed by the cutting die. The leakproof bottom film is coated with backing glue and wing glue, and then covered with release paper and small packaging film, and folded into a single sanitary napkin. It is packaged into a finished product by online packaging equipment.

[0177] Set up the experimental control group:

[0178] The absorbent core of the control group product is made of 0.4g of high absorbent resin, 3.3g of fluff pulp and 20gsm toilet paper. It is matched with materials such as surface layer, guide layer, leakproof edge, leakproof bottom film, release paper and small envelope. The main difference between the control group and the product of Example 3 is the different absorbent core.

[0179] Test analysis:

[0180] Material testing: In the same laboratory and experimental conditions (temperature 23±1℃, humidity 50±5%RH), the thickness, gram weight and wicking height (10min) of the upper and lower layers were tested respectively. The test data are as follows:

[0181] Test items thickness Weight Wicking height (10min) unit mm <![CDATA[g / m 2 ]]> mm upper layer 2.6 150 75 Lower level 0.9 80 130

[0182] In the same laboratory and experimental conditions (temperature 23±1℃, humidity 50±5%RH), the absorption rate was tested using the GB / T8939-2018 standard, and other items were tested using the enterprise standard Q / QMSD 086-2024 standard. The test results are as follows:

[0183] Test items Absorption rate Reverse osmosis Artificial menstrual blood absorption Bottom diffusion length Bottom diffusion width unit s g g mm mm Control group 24 0.5 52 82 56 Example 3 24 0.4 45 110 70

[0184] The raw materials or reagents used in the embodiments of the present invention and the comparative examples are all purchased from mainstream manufacturers in the market. Those without indicating the manufacturer or the concentration are all analytically pure raw materials or reagents that can be routinely obtained, as long as they can play the expected role, there is no particular restriction. The instruments and equipment such as the reactor and rotary evaporator used in the present embodiment are all purchased from major manufacturers in the market, as long as they can play the expected role, there is no particular restriction. If specific techniques or conditions are not indicated in the present embodiment, the techniques or conditions described in the literature in this area or according to the product specification are carried out.

[0185] The above embodiments are preferred implementation schemes of the present invention. In addition, the present invention may also be implemented in other ways. Any obvious replacement without departing from the concept of the present invention is within the protection scope of the present invention.

Claims

1. An absorbent core, characterized in that: It includes a plurality of upper layers attached together in sequence from top to bottom and a lower layer attached and arranged below the upper layers; The upper layer is a wood pulp layer made of 100% fluff pulp or a needle-punched cloth; The lower layer is spunlace cloth or dust-free paper.

2. An absorbent core according to claim 1, characterized in that: The method for preparing the wood pulp layer comprises the following steps: The wood pulp fibers are separated by a pulp board crusher, processed by a quantitative device and a forming hub, and demolded to form a wood pulp layer; the wood pulp layer is made of 100% fluff pulp, the fluff pulp has a gram weight of 1-5g, and a quantitative weight of 80-160g / m 2 , the thickness of the wood pulp layer is controlled at 1.5-3.0mm.

3. An absorbent core according to claim 1, characterized in that: The method for preparing the needle-punched cloth comprises the following steps: The absorbent cotton fibers are fully and evenly mixed, opened and impurity removed, and then combed into two layers of fiber webs by a carding machine. The two layers of fiber webs are needle-punched and reinforced by a needle-punched machine to form a needle-punched cloth to obtain the upper layer of the absorbent core; The single layer of the two-layer fiber web has a grammage of 40-80 gsm; the grammage of the needle-punched cloth is 80-150 gsm, and the thickness of the needle-punched cloth is controlled between 1.5-3.0 mm.

4. An absorbent core according to claim 1, characterized in that: The method for preparing the spunlace fabric comprises the following steps: a11) Manufacturing of pure cotton spunlace fabric The cotton fibers of different lengths are fully and evenly mixed, wherein the proportion of short fibers is 60%-90%; after loosening and removing impurities, the impurities in the fibers are removed, and the fibers are further mixed; the fibers are combed into a single-layer web with a grammage of 20-40gsm by a carding machine, and the two layers of webs are combined and drafted and transferred to the spunlace machine; the grey fabric is formed after pre-spunlace and positive and negative spunlace, and the spunlace pressures are: 70bar, 90bar, 90bar, 110bar and 110bar respectively; the spunlace drafting rates are 110%, 105%, 105%, 103% and 103%; b11) Degreasing and bleaching of spunlace grey fabric The spunlace grey fabric is rolled up by the equipment and transferred to the de-bleaching pot, where it undergoes pre-washing, boiling and bleaching, re-bleaching, washing and neutralization treatments; The pre-washing uses a refining agent, the temperature is set at 60°C, and the time is set to 30 minutes; the bleaching uses caustic soda, refining agent, hydrogen peroxide, and stabilizer, the temperature is set to 115°C, and the time is set to 90 minutes; The rebleaching process uses caustic soda, refining agent, hydrogen peroxide, and stabilizer, with the temperature set at 110°C and the time set at 90 minutes; the water washing and neutralization treatment uses hot water for two washes, normal temperature water for two washes, and the last wash is a citric acid solution; c11) Finishing of bleached cloth rolls The washed and neutralized cloth rolls are dried and subjected to single-sided water-repellent finishing; Drying is carried out in an oven or drying drum, the temperature is controlled at 102-110℃, and the drying time is 0.5h; the single-sided water-repellent finishing can be online spraying, transfer printing or coating finishing agent; d11) Cutting and packaging The spunlace cotton fabric rolls after single-sided water-repellent finishing are cut and packaged, and the width is 17-18cm.

5. An absorbent core according to claim 1, characterized in that: The method for preparing the spunlace fabric comprises the following steps: a21) Viscose spunlace fabric manufacturing The viscose fibers are fully dispersed and mixed, and then combed into a single-layer fiber web with a grammage of 20-40gsm by a carding machine; the two layers of fiber web and the interlayer wood pulp layer with a grammage of 10-20gsm are combined and transferred to the spunlace machine; the grey cloth is formed after pre-spunlacement, positive and negative spunlacement, and the spunlacement pressures are 70bar, 90bar, 90bar, 110bar and 110bar respectively; the spunlacement drafting rates are 110%, 105%, 105%, 103% and 103%; b21) Grey fabric finishing The fabric roll after spunlaced is dried and subjected to single-sided water-repellent finishing. The drying process uses an oven or a drying drum, the temperature is controlled at 102-110°C, and the drying time is 0.5h. The single-sided water-repellent finishing can be online spraying, transfer printing or coating finishing agent; c21) Cutting and packaging The cloth rolls after single-sided water-repellent finishing are cut and packaged, and the width is 17-18cm.

6. An absorbent core according to claim 1, characterized in that: The method for preparing the dust-free paper comprises the following steps: a31) Manufacturing of dust-free paper fabrics Hot melt fibers are mixed into wood pulp fibers, wherein the proportion of hot melt fibers is 15%-20%. After being air-laid, the low melting point fibers in the web are melted by hot air or hot rolling to reinforce the web into a grey cloth; wherein the weight of the grey cloth is 40-100gsm, and the thickness is controlled between 0.6-1.5mm; b31) Grey fabric finishing The grey cloth is rolled and subjected to single-sided water-repellent finishing, which can be an online spraying, transfer or coating finishing agent.

7. An absorbent core according to claim 1, characterized in that: The side of the lower layer away from the upper layer is a single-sided water-repellent surface.

8. A method for preparing an absorbent core according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1. Preparation of the upper layer A wood pulp layer or needle punched cloth made of 100% fluff pulp is used as the upper layer; S2. Preparation of the lower layer Use spunlace cloth or dust-free paper as the bottom layer; S3. Core composite Place the upper and lower layers of materials on the unwinding device, with the lower layer ensuring that its water-repellent surface is at the bottom; adhere the upper and lower layers together with hot melt adhesive. The thickness of the upper layer is controlled at 1.0-3.0mm, and the thickness of the lower layer is controlled at 0.1-1.0mm.

9. An application of an absorbent core, characterized in that: The absorbent core described in any one of claims 1 to 7 or the absorbent core manufactured by the preparation method described in claim 8 is applied to absorbent products.

10. The use according to claim 9, characterized in that: The absorbent products include sanitary napkins, menstrual pants, and diapers.

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