Sanitary towel with ultrathin absorber

Abstract

The invention discloses a sanitary napkin with an ultrathin absorber, and belongs to the field of sanitary napkin absorbers, a core body comprises a hot air non-woven fabric, a first SAP layer, a first dust-free paper, a second SAP layer and a second dust-free paper, the low-gram-weight hot air non-woven fabric is arranged as a core body surface layer, and the surface layer does not directly lock water and focuses on diversion transfer; the double-layer SAP separated by the first dust-free paper in the middle and the particle laying design that the upper layer of the double-layer SAP is small, the lower layer of the double-layer SAP is thin and the lower layer of the double-layer SAP is large and thick are adopted, so that the absorption speed is ensured, the total absorption amount is ensured, and the first dust-free paper for middle isolation can provide better structural support and play a role in secondary flow guide; the bottom layer is used for supporting the bottom layer and preventing leakage, a carrier structure of hot air, dust-free paper and dust-free paper is achieved, the core body is better prevented from being deformed and broken due to the fact that the SAP absorbs water and expands, the problems of lumping and fault of the core body are better avoided, and the ultrathin core body is more convenient to achieve.

Description

Technical Field

[0001] This invention belongs to the field of sanitary napkin absorbent bodies, and specifically relates to a sanitary napkin with an ultra-thin absorbent body. Background Technology

[0002] Traditional sanitary napkin absorbents are composed of fluff pulp and polymers, with fluff pulp as the main framework. Polymer particles are mixed into the loose wood pulp fibers, and the loose structure of the wood pulp supports the absorbent space. To reduce the thickness of the absorbent core, current ultra-thin sanitary napkins use a method of fixing superabsorbent polymer (SAP) onto clean paper to create the ultra-thin absorbent core. However, in current technology, the traditional ultra-thin core structure is simply a layering of different structures, thus presenting the following problems: 1. Absorption is easily concentrated: After the liquid enters the core, due to the lack of an effective flow guiding structure, it is concentrated in the central area in a short time, which leads to the rapid saturation of local superabsorbent resin, while the surrounding absorbent material is idle, resulting in low overall absorption capacity utilization of the core. 2. Slow diffusion rate: Due to the simple pore structure, the liquid is difficult to diffuse rapidly in both the lateral and longitudinal directions. Even if a traditional guide channel is set up, the blocking effect formed at the edge of the channel will restrict the liquid from being transported to the side. 3. Poor absorption: The above problems directly lead to increased backflow of liquid, insufficient surface dryness, uneven absorption, and insufficient internal non-woven fabric support. They can also cause the core to bulge and deform after local expansion, failing to meet the dual requirements of ultra-thin sanitary napkins for absorption efficiency and comfort. Summary of the Invention

[0003] (a) Technical problems to be solved In order to overcome the shortcomings of existing technology, a sanitary napkin with an ultra-thin absorbent body is proposed to solve one or more of the above problems.

[0004] (II) Technical Solution This invention is achieved through the following technical solution: This invention proposes a sanitary napkin with an ultra-thin absorbent body, the structure of which includes a core, the core being assembled inside the sanitary napkin; The core comprises a hot-air nonwoven fabric, a first SAP layer, a first cleanroom paper, a second SAP layer, and a second cleanroom paper. The hot-air nonwoven fabric is the surface layer, the second cleanroom paper is the bottom layer, and the first cleanroom paper is the middle layer. The first SAP layer is uniformly laid between the hot-air nonwoven fabric and the first cleanroom paper, and the second SAP layer is uniformly laid between the first and second cleanroom papers. The hot-air nonwoven fabric uses a low basis weight material. The particle size and amount of the first SAP layer are lower than those of the second SAP layer. The basis weight of the first cleanroom paper is lower than that of the second cleanroom paper. The first cleanroom paper is used for intermediate support and secondary airflow, and the second cleanroom paper is used for bottom layer support and leak prevention.

[0005] Furthermore, the weight of the hot air nonwoven fabric is 20-35 g / m², and the fiber structure is loose but uniform.

[0006] Furthermore, the particle size of the first SAP layer is 100-300μm, and the laying amount is 15-40g / ㎡.

[0007] Furthermore, the particle size of the second SAP layer is 200-400μm, and the laying amount is 60-125g / ㎡.

[0008] Furthermore, the first cleanroom paper is a 30-40 g / m² cleanroom paper produced by hot air method or needle punching method.

[0009] Furthermore, the second cleanroom paper is a high-density cleanroom paper with a weight of 40-60 g / m².

[0010] (III) Beneficial Effects One of the above technical solutions has the following advantages or beneficial effects: By using a low-basis-weight hot-air nonwoven fabric as the core and surface layer, the fiber structure is loose yet uniform. Utilizing the slight hydrophilicity of the fibers compared to the lower layer, liquid is quickly dispersed and guided to the lower polymer layer, leaving no liquid residue and ensuring a dry surface. This prevents direct water retention and focuses on liquid transfer. Combined with a double-layer SAP setup separated by an intermediate first cleanroom paper, and the first SAP layer having a smaller particle size and lower density than the second SAP layer, this achieves rapid absorption in the upper first SAP layer and high absorption in the lower second SAP layer. This ensures both absorption speed and total absorption capacity. The intermediate cleanroom paper provides better structural support and acts as a secondary guide, preventing liquid from being trapped in the surface. While the AP particles adhere and clump together, the unabsorbed liquid in the first SAP layer can be quickly guided to the second SAP layer below. Combined with the second cleanroom paper at the bottom for bottom support and leak prevention, the three-layer carrier structure of hot air + cleanroom paper + cleanroom paper better prevents the core from deforming and cracking due to the expansion of SAP water absorption, thus better avoiding the problems of core clumping and breakage. Through the exclusive functional design and cooperation of each layer, directional flow guidance, layered water locking and isolation support are achieved. Compared with traditional sanitary napkin cores, fewer structural layers are required. Only three carrier layers are needed to achieve a sanitary napkin core that is extremely dry, leak-proof, water-locking and structurally stable, making it easier to achieve an ultra-thin structure of less than 1.5mm. Attached Figure Description

[0011] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram of the structural layers of the present invention; In the diagram: Sanitary napkin-1, core-2, hot air nonwoven fabric-201, first SAP layer-202, first cleanroom paper-203, second SAP layer-204, second cleanroom paper-205. Detailed Implementation

[0012] The present invention will be further described in detail below with reference to embodiments, but the implementation of the present invention is not limited thereto.

[0013] This invention provides a sanitary napkin with an ultra-thin absorbent core: its structure includes a core 2, which is assembled inside the sanitary napkin 1; The core 2 includes a hot air nonwoven fabric 201, a first SAP layer 202, a first cleanroom paper 203, a second SAP layer 204, and a second cleanroom paper 205. The hot air nonwoven fabric 201 is the surface layer, which is in direct contact with the liquid. The second cleanroom paper 205 is the bottom layer, and the first cleanroom paper 203 is the middle layer. The first SAP layer 202 is uniformly laid between the hot air nonwoven fabric 201 and the first cleanroom paper 203, and the second SAP layer 204 is uniformly laid between the first cleanroom paper 203 and the second cleanroom paper 205. The hot air nonwoven fabric 201 uses a low basis weight material. The particle size and laying amount of the first SAP layer 202 are lower than those of the second SAP layer 204. The basis weight of the first cleanroom paper 203 is lower than that of the second cleanroom paper 205. The first cleanroom paper 203 is used for intermediate support and secondary flow guidance, and the second cleanroom paper 205 is used for bottom layer support and leak prevention.

[0014] In one embodiment, the hot air nonwoven fabric 201 has a basis weight of 20-35 g / m² and a loose but uniform fiber structure.

[0015] In one embodiment, the particle size of the first SAP layer 202 is 100-300μm, and the laying amount is 15-40g / ㎡.

[0016] In one embodiment, the particle size of the second SAP layer 204 is 200-400 μm, and the layup amount is 60-125 g / ㎡.

[0017] In one embodiment, the first cleanroom paper 203 is a 30-40 g / m² cleanroom paper produced by hot air method or needle punching method, with dense fibers and a certain strength.

[0018] In one embodiment, the second cleanroom paper 205 is a high-density cleanroom paper with a weight of 40-60 g / m² and the lowest hydrophilicity.

[0019] In use, the design of the hot air nonwoven fabric 201 surface layer serves to quickly receive and initially guide the liquid. As the first barrier to liquid contact, the loosely structured hot air nonwoven fabric 201 can instantly "catch" the liquid, preventing local accumulation. Simultaneously, utilizing the slight hydrophilicity of the fibers below, it quickly disperses the liquid and guides it to the underlying polymer layer, leaving no liquid residue and ensuring a dry surface. This prevents the surface from directly locking in water, focusing instead on "guiding and transferring" the liquid, essentially acting as a "first conveyor belt" for the liquid. The next layer, the first SAP layer 202, forms the first water-locking layer, achieving rapid initial water-locking. It receives the liquid guided from the hot air layer, instantly absorbs it, and expands and gels, "fixing" most of the liquid and preventing backflow or lateral diffusion, thus buying time for the lower layers to absorb it. The design of the middle layer, the first dust-free paper 203, serves as intermediate support and secondary guidance. On one hand, it acts as a "separator" between the upper and lower layers of polymer, preventing polymer particles from sticking together and clumping. On the other hand, its dense fiber structure can quickly guide the small amount of liquid that is not fully absorbed by the first layer of polymer to the second layer below, while preventing the lower layer of gelled polymer from penetrating upwards, increasing the absorption effect while reducing backflow. Next, the second SAP layer 204 is set as the core second shrinkage layer, playing a role in deep water locking. It receives the remaining liquid guided down from the first cleanroom paper 203, and with a higher layer density and slightly larger particle size than the first SAP layer 202, it achieves "bottom-up" absorption, completely locking the liquid in the lower layer of the core, greatly improving backflow prevention. Finally, the bottom design of the second cleanroom paper 205 achieves the functions of bottom support and leak-proof bottom-up. As the "base" of the entire core, it provides structural stability, preventing the lower SAP layer from cracking due to water absorption and expansion; at the same time, its low hydrophilicity prevents the water-locked gel from leaking out of the core, completely cutting off the path of liquid leakage downwards or sideways.

[0020] In summary, this application employs a stepped absorption method of "flow guidance - water locking - re-flow guidance - re-water locking": liquid enters from the surface hot air nonwoven fabric 201, is initially locked by the first SAP layer 202, and the unabsorbed liquid is conducted through the middle first dust-free paper 203 to the second SAP layer 204 for deep water locking, forming a "stepped" absorption path to prevent liquid from accumulating in a certain layer; Meanwhile, the first SAP layer 202 and the second SAP layer 204 of this application adopt a distribution method of "thin on top and thick on the bottom, less on top and more on the bottom": the upper layer of SAP is less and finer, focusing on "fast absorption"; the lower layer of SAP is more and coarser, focusing on "more absorption", which ensures both absorption speed and total absorption. Furthermore, the three-layer carrier structure of this application, consisting of hot air + cleanroom paper + cleanroom paper, ensures structural stability: the two SAP layers are firmly fixed by the three-layer fiber carrier, and the design of the first cleanroom paper 203 in the middle and the second cleanroom paper 205 at the bottom can better prevent the first SAP layer 202 and the second SAP layer 204 from sticking together. At the same time, it can better prevent the core from deforming and cracking due to the expansion of the first SAP layer 202 and the second SAP layer 204 due to water absorption. This completely solves the problem of "clumping and delamination" of traditional cores, while achieving ultra-thin cores (the overall thickness can be controlled within 0.8-1.5mm).

[0021] This application achieves a breakthrough from both structural design and material properties, completely solving the problems of liquid backflow and side leakage in traditional sanitary napkins, and significantly improving dryness and safety protection.

[0022] In the description of this invention, it should be noted that the terms "upper", "lower", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0023] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims. Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider 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 sanitary napkin with an ultra-thin absorbent core, the structure of which includes a core (2) assembled inside the sanitary napkin (1); Its features are: The core (2) includes a hot air nonwoven fabric (201), a first SAP layer (202), a first cleanroom paper (203), a second SAP layer (204), and a second cleanroom paper (205). The hot air nonwoven fabric (201) is the surface layer, the second cleanroom paper (205) is the bottom layer, and the first cleanroom paper (203) is the middle layer. The first SAP layer (202) is evenly laid between the hot air nonwoven fabric (201) and the first cleanroom paper (203). A second SAP layer (204) is uniformly laid between (203) and the second cleanroom paper (205). The hot air nonwoven fabric (201) uses a low basis weight material. The particle size and laying amount of the first SAP layer (202) are lower than those of the second SAP layer (204). The basis weight of the first cleanroom paper (203) is lower than that of the second cleanroom paper (205). The first cleanroom paper (203) is used for intermediate support and secondary flow guidance. The second cleanroom paper (205) is used for bottom layer support and leak prevention.

2. A sanitary napkin with an ultra-thin absorbent body according to claim 1, characterized in that: The hot air nonwoven fabric (201) has a basis weight of 20-35 g / m² and a loose but uniform fiber structure.

3. A sanitary napkin with an ultra-thin absorbent body according to claim 1 or 2, characterized in that: The first SAP layer (202) has a particle size of 100-300μm and a laying amount of 15-40g / ㎡.

4. A sanitary napkin with an ultra-thin absorbent body according to claim 3, characterized in that: The particle size of the second SAP layer (204) is 200-400μm, and the amount of material laid is 60-125g / ㎡.

5. A sanitary napkin with an ultra-thin absorbent body according to claim 1, 2, or 4, characterized in that: The first cleanroom paper (203) is a 30-40 g / m² cleanroom paper produced by hot air method or needle punching method.

6. A sanitary napkin with an ultra-thin absorbent body according to claim 5, characterized in that: The second cleanroom paper (205) is a high-density cleanroom paper with a weight of 40-60 g / m².

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