Liquid absorbent pad having split absorbent

Abstract

The application discloses a liquid absorption pad with split absorption bodies and belongs to the technical field of liquid absorption pads. The liquid absorption pad comprises at least two absorption bodies, a waterproof and breathable film and a water-impermeable bottom layer. The length and width directions of the absorption bodies are consistent with the overall length and width directions, respectively, and the absorption bodies have two side surfaces along the width direction. The at least two absorption bodies are arranged at intervals along the width direction of the liquid absorption pad and extend along the length direction of the liquid absorption pad. The waterproof and breathable film does not cover the adjacent absorption bodies, forming a breathable channel. The breathable channel forms a breathable path in communication with the outside. The waterproof and breathable film is connected with the lower surface of the absorption body. The water-impermeable bottom layer is arranged below the waterproof and breathable film and fixedly connected with the waterproof and breathable film. The split absorption bodies are designed to form the breathable channel and cooperate with the specific leakage-proof structure, so that the problems of the limited absorption efficiency and capacity, the poor breathability and the poor leakage-proof effect of the existing liquid absorption pad are solved.

Description

Technical Field

[0001] This invention relates to the field of liquid absorbent pad technology, specifically to a liquid absorbent pad with a split absorbent body, applicable to the field of hygiene care products, including applications such as menstrual care, infant care, pet care, and adult incontinence care. Background Technology

[0002] In the field of liquid absorbent pad technology, the performance of liquid absorbent pads is crucial. For example, they are used in medical care to absorb bodily fluids and in women's menstrual cycles to absorb menstrual blood. Traditional liquid absorbent pads typically use a one-piece absorbent core. While they have some absorbency, the overall coverage of the core results in poor breathability. During use, air cannot circulate beneath the core, leading to a stuffy feeling, especially during prolonged use, significantly impacting user comfort.

[0003] Furthermore, existing liquid absorbent pads have shortcomings in their leak-proof design. When absorbing liquid, the diffusion and distribution of the liquid within the absorbent body are not uniform enough, making it easy for liquid to overflow from the sides. This is because the integral absorbent body lacks lateral blocking structures, and the lateral diffusion path of the liquid is limited, resulting in limited absorption efficiency and capacity, causing inconvenience and hygiene problems. Therefore, improving the breathability and leak-proof performance of liquid absorbent pads has become a pressing technical problem to be solved in this field. Summary of the Invention

[0004] In existing technologies, such as CN119279925A, a type of leak-proof sanitary napkin with a wrap-around design is disclosed. While this improves breathability through a through-channel in the width direction, it does not employ a separate absorbent core design, and the absorbent core lacks a U-shaped leak-proof structure with a waterproof and breathable membrane covering the sides. This results in liquid easily overflowing from the sides of the absorbent core, and the breathable channel does not fully extend along the length of the absorbent pad, limiting its breathability. To address the shortcomings of existing technologies, the purpose of this invention is to provide a liquid absorbent pad with a separate absorbent core. This design creates a breathable channel and works synergistically with a specific leak-proof structure to solve the problems of limited absorption efficiency and capacity, poor breathability, and inadequate leak-proof performance of existing liquid absorbent pads mentioned in the background.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows:

[0006] A liquid absorbent pad with separate absorbent bodies includes at least two absorbent bodies, a waterproof and breathable membrane, and a waterproof bottom layer. The long side of the liquid absorbent pad is defined as its overall length direction, and the short side as its overall width direction. The length and width directions of each absorbent body are consistent with the overall length and width directions, respectively. Each absorbent body has two side surfaces along its width direction. The at least two absorbent bodies are arranged at intervals along the width direction of the liquid absorbent pad and extend along the length direction of the liquid absorbent pad. Adjacent absorbent bodies are not covered by the waterproof and breathable membrane, forming a breathable channel that runs through the length direction of the liquid absorbent pad, creating a breathable path connecting to the outside. The waterproof and breathable membrane is connected to the lower surface of the absorbent bodies. The waterproof bottom layer is disposed below the waterproof and breathable membrane and is fixedly connected to the waterproof and breathable membrane.

[0007] Furthermore, the connection method between the waterproof and breathable membrane and the absorbent is selected from hot pressing, ultrasonic welding, or adhesive bonding.

[0008] Furthermore, the connection method between the impermeable substrate and the waterproof and breathable membrane is selected from hot pressing, ultrasonic welding, or adhesive bonding.

[0009] Furthermore, the waterproof and breathable membrane is connected to the lower surface of the absorbent and extends along the width of the absorbent to wrap around both sides, forming a U-shaped leak-proof structure that wraps around the lower and both sides.

[0010] The beneficial effects of this invention are as follows:

[0011] This invention provides an absorption system by setting at least two absorbers spaced apart along the width of the waterproof and breathable membrane. Liquid can be absorbed by multiple absorbers simultaneously, reducing the load on a single absorber, promoting lateral diffusion of the liquid, avoiding local saturation, and thus improving the overall absorption efficiency and capacity.

[0012] This invention designs the absorbent elements as a split structure spaced apart along the width direction, forming breathable channels between adjacent absorbent elements. These channels extend along the length direction, connecting to the outside environment, significantly improving the breathability of the absorbent pad. This allows for the timely removal of humid and hot air from beneath the absorbent elements, maintaining a dry and comfortable environment. Simultaneously, a waterproof and breathable membrane wraps around the lower and side surfaces of the absorbent elements, forming a U-shaped leak-proof structure. Combined with multiple secure connection methods between the waterproof and breathable membrane, the absorbent elements, and the impermeable underlayer, liquid leakage is effectively prevented, enhancing the reliability and practicality of the absorbent pad. Attached Figure Description

[0013] Figure 1These are top views of Embodiments 1 and 3 of the present invention. The figures show the absorbent 11, absorbent 12, waterproof and breathable membrane 2, and breathable channel 4. Although the impermeable bottom layer 3 is not directly shown in the top view, it is actually located at the bottom of the entire structure. Diagonal stripes are added to the surfaces of the two absorbents for differentiation. The absorbents 11 and 12 are arranged at intervals along the width of the liquid absorption pad, forming a breathable channel 4 between them. The impermeable bottom layer 3 is located at the bottom, covering the entire bottom area of ​​the liquid absorption pad.

[0014] Figure 2 This is a cross-sectional structural diagram of Embodiments 1 and 3 of the present invention, illustrating the internal structural relationship of the liquid absorbent pad. The diagram shows the cross-sectional shapes of the absorbent body 11, absorbent body 12, waterproof and breathable membrane 2, and impermeable bottom layer 3. The absorbent bodies 11 and 12 are arranged at intervals along the width direction of the liquid absorbent pad, forming a breathable channel 4 between them. The waterproof and breathable membrane 2 is connected to the lower surfaces of the absorbent bodies 11 and 12, and extends along the width direction of the absorbent bodies to wrap around both sides, forming a U-shaped structure. The impermeable bottom layer 3 is fixedly connected to the waterproof and breathable membrane 2 and is located below it.

[0015] Figure 3 This is a top view of Embodiment 2 of the present invention. The figure shows absorbent body 51, absorbent body 52, absorbent body 53, waterproof and breathable membrane 6, breathable channel 81, and breathable channel 82. Although the impermeable bottom layer 7 is not directly shown in the top view, it is actually located at the bottom of the entire structure. The surfaces of the three absorbent bodies are marked with diagonal lines and are arranged at intervals along the width of the liquid absorption pad. Breathable channels 81 and 82 are formed between adjacent absorbent bodies, respectively. The impermeable bottom layer 7 covers the entire bottom area of ​​the liquid absorption pad.

[0016] Figure 4 This is a cross-sectional structural diagram of Embodiment 2 of the present invention, showing the internal structure of the liquid absorbent pad in Embodiment 2. The diagram shows the cross-sectional shapes of absorbent body 51, absorbent body 52, absorbent body 53, waterproof and breathable membrane 6, and impermeable bottom layer 7. Breathable channels 81 and 82 are formed between adjacent absorbent bodies. The waterproof and breathable membrane 6 is connected to the lower surfaces of absorbent bodies 51, 52, and 53 and wraps around both sides to form a U-shaped leak-proof structure. The impermeable bottom layer 7 is fixedly connected to the waterproof and breathable membrane 6 below.

[0017] Figure Labels

[0018] 11. Absorbent core; 12. Absorbent core; 2. Waterproof and breathable membrane; 3. Impermeable bottom layer; 4. Breathable channels;

[0019] 51. Absorbent; 52. Absorbent; 53. Absorbent; 6. Waterproof and breathable membrane; 7. Impermeable bottom layer; 81. Breathable channel; 82. Breathable channel. Detailed Implementation

[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0021] Example 1:

[0022] A liquid absorbent pad with a split absorbent body includes an absorbent body 11, an absorbent body 12, a waterproof and breathable membrane 2, and a waterproof bottom layer 3.

[0023] The liquid absorbent pad has an overall dimension of 280mm in length and 80mm in width, with the longer side representing the overall length and the shorter side representing the overall width. The length and width of absorbent bodies 11 and 12 are consistent with the overall length and width, respectively. Each absorbent body is a cylinder with a diameter of 25mm and a length of 260mm. Absorbent bodies 11 and 12 are arranged at 30mm intervals along the width of the liquid absorbent pad and extend along the length of the liquid absorbent pad. Adjacent absorbent bodies 11 and 12 are not covered by the waterproof and breathable membrane 2, forming a breathable channel 4. The breathable channel 4 runs through the length of the liquid absorbent pad, forming a breathable path that connects to the outside.

[0024] The waterproof and breathable membrane 2 is connected to the lower surfaces of absorbers 11 and 12 by hot-press bonding, and extends along the width of absorbers 11 and 12, wrapping around both sides to a height of 2mm, forming a U-shaped leak-proof structure that wraps around the lower and side surfaces. The waterproof and breathable membrane 2 is made of polypropylene waterproof and breathable membrane with a basis weight of 40g / m³. 2 Its air permeability is 300g / (m²). 2 •24h), with a thickness of 0.08mm and a microporous structure with a pore size of 0.1-1μm on the surface; this structure has good waterproof and breathable properties.

[0025] The impermeable base layer 3 is bonded to the waterproof and breathable membrane 2 using adhesive. The impermeable base layer 3 is made of polyethylene film with a thickness of 0.03 mm and a weight of 25 g / m². 2 With an elongation at break of ≥200%, it can effectively prevent liquid penetration.

[0026] Absorbent 11 and absorbent 12 are made of polypropylene spunbond nonwoven fabric wrapped with superabsorbent resin, wherein the superabsorbent resin content is 40%, the nonwoven fabric pore size is 50-100μm, the total weight of the absorbent is 30g, of which the SAP content is 40%, i.e., 12g. Under standard test conditions, the maximum liquid absorption capacity of a single absorbent can reach 75ml, which has good absorption capacity.

[0027] Example 2:

[0028] A liquid absorbent pad with a split absorbent body includes absorbent body 51, absorbent body 52, absorbent body 53, waterproof and breathable membrane 6, and waterproof bottom layer 7.

[0029] The liquid absorbent pad has an overall length of 280mm and a width of 80mm. The longer side of the liquid absorbent pad is along its overall length, and the shorter side is along its overall width. Each absorbent element is a cylinder with a diameter of 25mm and a length of 260mm. The length and width of absorbent elements 51, 52, and 53 are consistent with the overall length and width directions, respectively. Absorbent elements 51, 52, and 53 are evenly spaced along the width direction of the liquid absorbent pad and extend along its length direction. Adjacent absorbent elements 51, 52, and 53 are not covered by the waterproof and breathable membrane 6, forming breathable channels 81 and 82, respectively. Breathable channels 81 and 82 are continuous along the length direction of the liquid absorbent pad, forming a breathable path connecting to the outside.

[0030] The waterproof and breathable membrane 6 is also connected to the lower surface of each absorber using a heat-pressing bonding method. It extends along the width of each absorber and wraps around both sides of the membrane to a height of 2mm, forming a U-shaped leak-proof structure that wraps around the lower and side surfaces. The waterproof and breathable membrane 6 is made of polypropylene and has a breathability of 300g / (m³). 2 • 24h), thickness 0.08mm, basis weight 40g / m 2 The surface has a microporous structure with pore sizes of 0.1-1μm, and the waterproof bottom layer (material 7) is made of polyethylene film with a thickness of 0.03mm and a basis weight of 25g / m³. 2 The elongation at break is ≥200%, and the connection with the waterproof and breathable membrane 6 is made by ultrasonic welding to ensure a firm connection and prevent liquid leakage.

[0031] Absorbents 51, 52, and 53 are made of polypropylene spunbond nonwoven fabric wrapped with superabsorbent resin. The nonwoven fabric has a pore size of 50-100μm and a total weight of 30g, of which 40% (12g) is SAP. Under standard test conditions, the maximum liquid absorption capacity of a single absorbent can reach 75ml, which has good absorption capacity. Liquid can be absorbed and stored by the three absorbents at the same time, which can meet the needs of absorbing large amounts of liquid with fast flow rates.

[0032] In practical use, after the liquid is absorbed by the three absorbent elements, the presence of two ventilated channels allows for smoother airflow beneath the absorbent pad, further reducing stuffiness and improving user comfort compared to Example 1. Simultaneously, the U-shaped leak-proof structure, combined with a robust connection, effectively prevents liquid from overflowing from the sides of the absorbent elements, ensuring that liquid does not leak outside the absorbent pad and enhancing its effectiveness and reliability.

[0033] Example 3:

[0034] A liquid absorbent pad with a split absorbent body includes an absorbent body 11, an absorbent body 12, a waterproof and breathable membrane 2, and a waterproof bottom layer 3.

[0035] The liquid absorbent pad has an overall dimension of 280mm in length and 80mm in width, with the longer side representing the overall length and the shorter side representing the overall width. The length and width of absorbent bodies 11 and 12 are consistent with the overall length and width, respectively. Each absorbent body is a cylinder with a diameter of 25mm and a length of 260mm. Absorbent bodies 11 and 12 are arranged at 30mm intervals along the width of the liquid absorbent pad and extend along the length of the liquid absorbent pad. Adjacent absorbent bodies 11 and 12 are not covered by the waterproof and breathable membrane 2, forming a breathable channel 4. The breathable channel 4 runs through the length of the liquid absorbent pad, forming a breathable path that connects to the outside.

[0036] The waterproof and breathable membrane 2 is connected to the lower surfaces of absorbers 11 and 12 by hot-press bonding, and extends along the width of absorbers 11 and 12, wrapping around both sides to a height of 2mm, forming a U-shaped leak-proof structure that wraps around the lower and side surfaces. The waterproof and breathable membrane 2 is made of polypropylene waterproof and breathable membrane with a basis weight of 40g / m³. 2 Its air permeability is 300g / (m²). 2 •24h), with a thickness of 0.08mm and a microporous structure with a pore size of 0.1-1μm on the surface; this structure has good waterproof and breathable properties.

[0037] The impermeable base layer 3 is bonded to the waterproof and breathable membrane 2 using adhesive. The impermeable base layer 3 is made of polyethylene film with a thickness of 0.03 mm and a weight of 25 g / m². 2 With an elongation at break of ≥200%, it can effectively prevent liquid penetration.

[0038] Absorbent 11 and absorbent 12 are made of polypropylene spunbond nonwoven fabric wrapped with superabsorbent resin, wherein the superabsorbent resin content is 40%, the nonwoven fabric pore size is 50-100μm, the total weight of the absorbent is 30g, of which the SAP content is 80%, i.e., 24g. Under standard test conditions, the maximum liquid absorption capacity of a single absorbent can reach 150ml, which has good absorption capacity.

[0039] Test Method 1: Prepare three 100ml samples of simulated menstrual blood test solution (composition: 80% water, 15% glycerol, 3% sodium chloride, 2% hemoglobin). Simultaneously and uniformly pour the menstrual blood test solution onto the surface of the liquid absorption pads in Examples 1, 2, and 3. Start timing from the moment the menstrual blood contacts the absorption pad until it is completely absorbed, and record the time (unit: s) for each of the three examples. This time is the absorption rate of the liquid absorption pad. After the liquid absorption pads in Examples 1, 2, and 3 have completely absorbed 100ml of menstrual blood for 3 minutes, quantitative filter paper (pore size ≤ 5μm, basis weight 80g / m³) is applied to each pad. 2 The filter paper was placed flat on the corresponding absorbent pad surface. A 100g ± 0.1g weight was then gently placed on the filter paper. After 30 seconds, the weight and filter paper were removed. The weight of the three filter papers was measured using a precision balance. The increase in weight of the filter paper (in g) represents the backflow rate of the corresponding embodiment. A lateral pressure of 8 kPa was simultaneously applied to the liquid absorbent pad samples of Examples 1, 2, and 3. The lateral pressure was applied evenly to the side of the absorbent pad through a 5cm diameter cylindrical pressure head, simulating the side leakage pressure scenario caused by human activity during actual use. The presence and degree of side leakage in the three embodiments of the liquid absorbent pad under this pressure were observed and recorded to evaluate the leak-proof performance of the liquid absorbent pad. This test method refers to the test requirements for absorption rate, backflow rate, and leak-proof performance in GB / T8939 "Sanitary Napkins (including Panty Liners)".

[0040] Table 1. Test results of absorption rate, reverse seepage rate, and leak-proof performance in Examples 1, 2, and 3:

[0041] Liquid aspiration rate (s) 8.3 5.8 6.5 Reverse osmosis volume (g) 0.32 0.19 0.21 Leak-proof performance No leakage No leakage No leakage

[0042] In practical applications, comparative tests were conducted on Examples 1, 2, and 3, revealing significant performance differences among the examples. Example 2, employing three absorbers and an optimized ventilated channel design, achieved a 30.12% increase in absorption rate compared to Example 1 when absorbing 100ml of liquid. Example 3, while structurally identical to Example 1, featured an increased content of superabsorbent polymer (SAP), resulting in a 21.69% increase in absorption rate. Regarding backflow, Example 2, with its optimized structural design, reduced backflow compared to Example 1, achieving a 40.63% improvement in backflow performance. Compared to Example 3, Example 2's structural advantages further enhanced its backflow performance by 9.52%. These performance improvements effectively reduced liquid backflow and improved user comfort. In leak-proof performance tests, Examples 1, 2, and 3 all exhibited no liquid leakage when subjected to an 8kPa lateral pressure. This is thanks to the U-shaped leak-proof structure formed by the waterproof and breathable membrane wrapping the absorbent in each embodiment, as well as the firm connection with the impermeable bottom layer, which effectively prevents liquid from overflowing from the side of the absorbent and improves the performance and reliability of the absorbent pad.

[0043] Test Method 2: The liquid absorbent pads from Examples 1 and 2, as well as the traditional integral absorbent pad (control group), were tested according to GB / T 5453-1997 standard. Using a YG461E fully automatic fabric air permeability meter, the airflow rate through the absorbent pad per unit time was measured under a pressure difference of 100Pa. At the same time, a high-precision hot-wire anemometer was used to measure the inlet and outlet wind speeds of the air permeability channel, calculate the wind speed difference, and evaluate the air circulation effect.

[0044] Table 2 shows the inlet and outlet wind velocities for Examples 1 and 2 and the control group, and the calculated wind speed difference test results.

[0045] airflow <![CDATA[20L / (m 2 ·s)]]> <![CDATA[28L / (m 2 ·s)]]> <![CDATA[5L / (m 2 ·s)]]> Wind speed difference 0.35m / s 0.47m / s 0.13m / s

[0046] Experimental results show that the liquid absorbent pads of Examples 1 and 2, thanks to their split absorbent body design, exhibit better breathability compared to the control group. Example 2, compared to Example 1, further improves various performance aspects by increasing the number of absorbent bodies and optimizing the width of the breathable channels. This invention, through its unique breathable channel design, achieves efficient moisture dissipation and heat dissipation, solving the problems of stuffiness and dampness caused by insufficient breathability in traditional liquid absorbent pads.

[0047] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A liquid absorbent pad with separate absorbent bodies, comprising at least two absorbent bodies, a waterproof and breathable membrane, and a waterproof bottom layer, characterized in that: The long side of the liquid absorbent pad is defined as the overall length direction, and the short side is defined as the overall width direction; the length and width directions of the absorbent body are consistent with the overall length and width directions, respectively, and the absorbent body has two side surfaces along the width direction; The at least two absorbents are arranged at intervals along the width direction of the liquid absorbent pad and extend along the length direction of the liquid absorbent pad. The adjacent absorbents are not covered by a waterproof and breathable membrane, forming a breathable channel that runs through the length direction of the liquid absorbent pad. The breathable channel forms a breathable path that communicates with the outside. The waterproof and breathable membrane is connected to the lower surface of the absorbent; The impermeable bottom layer is disposed below the waterproof and breathable membrane and is fixedly connected to the waterproof and breathable membrane.

2. The liquid absorbent pad with a split absorbent body according to claim 1, characterized in that, The connection method between the waterproof and breathable membrane and the absorbent is selected from hot pressing, ultrasonic welding or adhesive bonding.

3. The liquid absorbent pad with a split absorbent body according to claim 1, characterized in that, The connection method between the impermeable bottom layer and the waterproof and breathable membrane is selected from hot pressing, ultrasonic welding or adhesive bonding.

4. The liquid absorbent pad according to claim 1, characterized in that, The waterproof and breathable membrane is connected to the lower surface of the absorbent and extends along the width of the absorbent to wrap around both sides, forming a U-shaped leak-proof structure that wraps around the lower and both sides.

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