Liquid absorbing patch for bloodletting by needling

Abstract

The present application relates to the technical field of medical devices, and provides a liquid absorption patch for blood-letting, comprising a flow guide layer, an absorption layer and a liquid storage layer; the flow guide layer is arranged towards a wound surface, and has a plurality of through holes in the interior for receiving blood flowing out of the wound surface; the absorption layer is arranged on the side of the flow guide layer away from the wound surface, and has three-dimensional pores in stereoscopic communication, the pores being in communication with the through holes; the absorption layer comprises a central thickened area and a peripheral area surrounding the central thickened area, the thickness of the central thickened area being greater than that of the peripheral area; the liquid storage layer is arranged on the side of the absorption layer away from the flow guide layer, and is used for forming a gel after absorbing blood. The liquid absorption patch for blood-letting provided by the present application avoids the formation of a liquid film on the surface of the liquid absorption patch and the lateral diffusion and edge overflow of high-speed and high-flow blood generated by blood-letting, and achieves instantaneous adsorption, large-capacity storage and gel-state locking, thereby improving the blood absorption effect of the liquid absorption patch on blood-letting.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to an absorbent patch for bloodletting. Background Technology

[0002] In traditional Chinese medicine treatment of varicose veins in the lower extremities, bloodletting is used, resulting in a high-speed, large-volume flow of blood along the lower limbs. Ordinary medical dressings (such as regular gauze, foam dressings of equal thickness, or adhesive bandages) and thickened absorbent materials are typically used to capture and collect the blood, preventing environmental contamination or increasing the risk of infection.

[0003] In practical applications, when the rate of blood outflow is greater than the rate of blood seepage into the medical dressing or absorbent material, the blood spreads into a film on the surface of the dressing or absorbent material and diffuses laterally, eventually overflowing from the edges. Summary of the Invention

[0004] This invention provides an absorbent patch for bloodletting, which solves the problem that in the prior art, when blood flows quickly and in large quantities, a liquid film easily forms on the surface of the medical dressing or absorbent material and overflows from the edges.

[0005] This invention provides an absorbent patch for bloodletting, comprising: A drainage layer is positioned facing the wound surface and has multiple through-holes penetrating the drainage layer, which are used to collect blood flowing out of the wound surface. An absorbent layer is disposed on the side of the drainage layer opposite to the wound surface. The absorbent layer has three-dimensional interconnected channels, which are connected to the through holes. The absorbent layer includes a central thickened area and an edge area surrounding the central thickened area. The thickness of the central thickened area is greater than the thickness of the edge area. A reservoir layer is located on the side of the absorbent layer opposite to the guide layer, and is used to absorb blood and form a gel.

[0006] According to the present invention, an absorbent patch for bloodletting is provided, wherein the absorbent layer further includes a transition zone; The transition zone is located between the central thickened zone and the edge zone, and the transition zone has a curved surface structure or a stepped structure.

[0007] According to the present invention, the thickness of the central thickened area is h1, and the thickness of the edge area is h2, satisfying: 8mm≤h1≤15mm, 2mm≤h2≤5mm; And / or, the projection of the central thickened area onto a plane perpendicular to the thickness direction of the absorbent patch has a length of 5mm to 11mm along the length direction of the absorbent patch and a length of 3mm to 6mm along the width direction of the absorbent patch. And / or, the thickness of the edge regions is the same; And / or, the length of the projection of the transition zone onto a plane perpendicular to the thickness direction of the absorbent patch is 5mm to 20mm, and in the case where the transition zone has a curved surface structure, the angle between the tangent along the curved surface of the transition zone and the edge zone is 5° to 25°.

[0008] According to the present invention, an absorbent patch for bloodletting is provided, wherein the absorbent layer is a polyurethane foam layer; The porosity of the channels in the polyurethane foam layer is 85% to 95%, and the pore diameter is 0.3 mm to 2 mm.

[0009] According to the present invention, an absorbent patch for bloodletting is provided, wherein the liquid storage layer has capillary channels; The capillary channel is filled with absorbent resin particles, which absorb blood and form a gel within the capillary channel.

[0010] According to the present invention, an absorbent patch for bloodletting is provided, wherein the liquid storage layer is a core composed of fluff pulp and sodium polyacrylate superabsorbent polymer particles. The sodium polyacrylate superabsorbent polymer particles have a particle size of 100μm to 300μm and are uniformly dispersed in the fiber network of the fluff pulp.

[0011] According to the present invention, an absorbent patch for bloodletting is provided, wherein the liquid storage layer is provided with non-woven fabric wrapping layers on both sides; And / or, the thickness of the liquid storage layer is w, which satisfies: 2mm≤w≤5mm.

[0012] The absorbent patch for bloodletting provided by the present invention further includes: a backing layer; The backing layer is located on the side of the liquid storage layer away from the absorbent layer. The backing layer has a microporous structure and is used to prevent blood leakage and allow water vapor to pass through. And / or, the guide layer includes a central guide area and an adhesive area; The adhesive area is arranged around the central guide area, and the guide layer is provided with a first release film, which is peelably attached to the adhesive area.

[0013] According to the present invention, an absorbent patch for bloodletting is provided, wherein the through hole is a cylindrical hole; And / or, the through holes of the flow guiding layer are conical holes; along the thickness direction of the absorbent patch and toward the absorbent layer, the cross-sectional area of ​​the conical holes gradually increases.

[0014] An absorbent patch for bloodletting according to the present invention further includes: a wrapping tape; The flow guiding layer, the absorption layer, and the liquid storage layer are stacked and enclosed to form a ring structure, and the winding strips are respectively disposed at both ends of the ring structure.

[0015] The blood-absorbing patch provided by this invention comprises a flow-guiding layer, an absorption layer, and a storage layer. The flow-guiding layer is used for directional flow guidance. The absorption layer has a central thickened area and an edge area with different thicknesses, creating a capillary pressure gradient from the edge to the center, which adsorbs blood in the central thickened area. Furthermore, the storage layer enables the blood to form a gel, locking the blood in its storage location. This creates a blood-absorbing patch with a vertical functional gradient and a horizontal thickness gradient, preventing the high-speed, high-flow blood generated during bloodletting from forming a liquid film on the surface of the patch and laterally diffusing out from the edge. This achieves instantaneous adsorption, large-capacity storage, and gel-state locking, improving the absorption effect of the blood-absorbing patch on the blood from bloodletting. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is an exploded view of the first absorbent patch provided by the present invention.

[0018] Figure 2 This is a schematic diagram of the first absorbent patch provided by the present invention applied to the instep.

[0019] Figure 3 This is an exploded view of the second type of absorbent patch provided by the present invention.

[0020] Figure 4 This is a schematic diagram of the second type of absorbent patch provided by the present invention applied to the lower leg.

[0021] Figure label: 1. Absorbent patch; 11. Flow guiding layer; 12. Absorbent layer; 13. Liquid storage layer; 14. Backing layer; 15. First release film; 16. Second release film; 17. Wrapping tape; 18. Adhesive layer; 111. Central flow guiding zone; 112. Adhesive zone; 121. Central thickened zone; 122. Edge zone; 123. Transition zone; 100. Lower leg; 101. Wound. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0023] In the description of the embodiments of the present invention, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the purpose of clarifying the embodiments of the present 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 limitations on the embodiments of the present invention. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0024] In the description of the embodiments of the present invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention according to the specific circumstances.

[0025] In embodiments of the present invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0026] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0027] The following is combined Figures 1 to 4 The present invention will provide a detailed description of the absorbent patch for bloodletting provided in the embodiments of the present invention through specific examples and application scenarios.

[0028] like Figure 1 and Figure 2 As shown, this embodiment provides an absorbent patch 1 for bloodletting, comprising: a diversion layer 11, an absorption layer 12, and a liquid storage layer 13.

[0029] The drainage layer 11 is positioned facing the wound surface and has multiple through holes that penetrate the drainage layer 11. These through holes are used to collect blood flowing out of the wound surface.

[0030] The absorbent layer 12 is located on the side of the drainage layer 11 away from the wound surface. The absorbent layer 12 has three-dimensional channels that are interconnected and are connected to the through holes. The absorbent layer 12 includes a central thickened area 121 and an edge area 122 surrounding the central thickened area 121. The thickness of the central thickened area 121 is greater than the thickness of the edge area 122.

[0031] The liquid storage layer 13 is located on the side of the absorbent layer 12 away from the guide layer 11, and is used to form a gel after absorbing blood.

[0032] Understandably, in traditional Chinese medicine bloodletting therapy for varicose veins of the lower extremities, the blood flowing out of the wound 101 has the characteristics of high speed, large flow rate, and flowing along the curved surface. In this embodiment, the absorbent patch 1 is placed below the puncture site of the calf 100 to catch the blood flowing out of the wound, so as to prevent the blood from polluting the environment or increasing the risk of infection.

[0033] The drainage layer 11 is located on the outermost side of the absorbent patch 1. Multiple pores in the drainage layer 11 allow blood flowing from the wound 101 to be received and channeled towards the absorbent layer 12, dispersing the linear or planar blood into multiple droplets, increasing the contact area with the absorbent layer 12, and accelerating infiltration. Simultaneously, the multiple pores physically isolate the wound from the absorbent layer 12, preventing adhesion to the wound. Specifically, in this embodiment, the peel force of the drainage layer 11 is ≤0.1 N / cm.

[0034] In this embodiment, the absorption layer 12 can instantly capture and temporarily store the blood passing through the flow guiding layer 11. Since the absorption layer 12 has three-dimensional interconnected channels, it provides sufficient instantaneous containment space, which can absorb all the blood that initially flows out in a jet-like manner and contain it in the three-dimensional channels, preventing the blood from continuing to flow downward.

[0035] Furthermore, the absorbent layer 12 has a thicker central thickened region 121 and a thinner edge region 122. When blood comes into contact with the three-dimensional channels, the capillary pressure P is inversely proportional to the effective capillary radius r: P ∝ 1 / r. In the absorbent layer 12, the central thickened region 121 has a larger three-dimensional channel interconnection volume and a more complex network structure, resulting in a much stronger macroscopic blood-capturing capacity than the edge region 122. The thickness difference establishes a capillary pressure gradient from the edge to the center on a plane perpendicular to the thickness direction of the absorbent patch 1, meaning the central thickened region 121 forms a strong negative pressure sink.

[0036] When the high-speed blood flow generated by bloodletting falls on or near the central thickened region 121 of the absorbent layer 12, the strong negative pressure instantly delivers the blood into the three-dimensional channels inside the absorbent layer 12, achieving bulk absorption rather than surface spreading. Even if the blood initially falls on the edge region 122, the horizontal pressure gradient will drive the blood to automatically converge towards the central thickened region 121, thereby increasing the absorption rate by 3 to 5 times compared to an absorbent layer 12 of equal thickness, and preventing the formation of a surface liquid film and edge overflow.

[0037] Furthermore, the thickness of the absorbent layer 12 smoothly decreases from the center to the edge, forming a flexible gradient. The thin and soft edge area 122 perfectly conforms to the cylindrical curved surface of the calf 100, while the central thickened area 121 naturally fits into the depressions on the skin surface or is close to the wound. Because this structure eliminates stress concentration points caused by abrupt changes in edge thickness in traditional thickened dressings, it ensures that the edge area 122 will not lift up and form leakage channels even in moist environments or when the patient is slightly active.

[0038] The reservoir layer 13 slowly draws blood from the absorbent layer 12 through capillary action, transforming the blood into a non-flowing gel. This achieves in-situ locking of the blood, preventing backflow when the patient's position changes or pressure is applied, and further avoiding blood flow at the edges. Simultaneously, the space of the three-dimensional pores in the absorbent layer 12 is released, restoring its absorption capacity to cope with any subsequent minor bleeding.

[0039] The absorbent patch 1 used for bloodletting in this embodiment is a disposable sterile product. Each layer is laminated with hot melt adhesive or ultrasonic spot welding, sterilized by ethylene oxide or irradiation, and individually packaged.

[0040] The present invention provides a bloodletting patch 1 with a flow guiding layer 11, an absorption layer 12, and a storage layer 13. The flow guiding layer 11 is used for directional flow guidance. The absorption layer 12 is provided with a central thickened area 121 and an edge area 122 of different thicknesses to form a capillary pressure gradient from the edge to the center, which adsorbs blood in the central thickened area 121. Furthermore, the storage layer 13 enables the blood to form a gel, locking the blood storage position. This creates a bloodletting patch 1 with a vertical functional gradient and a horizontal thickness gradient, preventing the high-speed, high-flow blood generated by bloodletting from forming a liquid film on the surface of the patch 1 and spreading laterally from the edge. This achieves instantaneous adsorption, large-capacity storage, and gel-state locking, improving the absorption effect of the bloodletting patch 1 on the bloodletting.

[0041] like Figure 1 As shown, the absorption layer 12 in this embodiment also includes a transition region 123.

[0042] The transition zone 123 is located between the central thickened zone 121 and the edge zone 122, and the transition zone 123 has a curved surface structure or a stepped structure.

[0043] Understandably, the central thickened area 121 and the edge area 122 are smoothly connected by a transition area 123 to avoid an abrupt transition structure between the central thickened area 121 and the edge area 122.

[0044] Specifically, the transition zone 123 can be a curved surface structure, connecting the central thickened zone 121 and the edge zone 122 through the curved surface. The transition zone 123 can also be a stepped structure, achieving a gradual connection of different heights between the central thickened zone 121 and the edge zone 122 through multiple steps.

[0045] like Figure 1 As shown, in this embodiment, the thickness of the central thickened area 121 is h1, and the thickness of the edge area 122 is h2, satisfying: 8mm≤h1≤15mm, 2mm≤h2≤5mm.

[0046] Understandably, based on conventional data of the wound on the patient's lower leg 100, the thickness of the central thickened area 121 and the edge area 122 in this embodiment need to meet certain ranges.

[0047] Specifically, h1 can be 8mm, 11.5mm, or 15mm. h2 can be 2mm, 3.5mm, or 5mm.

[0048] Under a limited thickness and a pressure of 1.5 kPa, the absorbent patch 1 of this embodiment achieves an absorption rate of ≥8 mL / (cm²) for simulated blood (viscosity 3.5 mPa·s). 2The capillary pressure difference between the central thickened zone 121 and the edge zone 122 is ≥500 Pa, driving blood to converge towards the central thickened zone 121. The absorbent capacity of the absorbent layer 12 is 40–60 mL.

[0049] In the comparative experiment, a bionic calf model was used, and 50 mL of simulated blood was injected into the model at a rate of 10 mL / s. The control group used foam of uniform thickness. After 1.2 seconds, approximately 8 mL of simulated blood overflowed from the edge of the control group. The absorbent patch 1 in this embodiment exhibited no liquid film on its surface and zero overflow, resulting in a 3-5 times increase in absorption rate.

[0050] like Figure 1 As shown, in this embodiment, the projection of the central thickened area 121 onto a plane perpendicular to the thickness direction of the absorbent patch 1 has a length of 5mm to 11mm along the length direction of the absorbent patch 1 and a length of 3mm to 6mm along the width direction of the absorbent patch 1.

[0051] Understandably, since the blood flow rate for bloodletting on the lower leg 100 is constant, the central thickened area 121 in this embodiment has a certain area requirement. This area is sufficient to absorb the amount of blood released in one session, but not so large that it is difficult to apply to the lower leg 100. The absorbent patch 1 typically adopts a square structure, with a projection along the length direction of the lower leg 100 and a projection along the width direction perpendicular to the length direction of the lower leg 100.

[0052] Specifically, the length of the projection can be 5mm, 8mm, or 11mm. The width of the projection can be 3mm, 4.5mm, or 6mm.

[0053] like Figure 1 As shown, the edge region 122 in this embodiment has the same thickness.

[0054] It is understood that the thickness of the edge area 122 in this embodiment is set to be relatively small. It is smoothly connected to the central thickened area 121 through the transition area 123 to form a flexible gradient, thereby eliminating the lifting and side leakage of the edge area 122 and making the transition area 123 fit firmly.

[0055] The absorbent patch 1 of this embodiment was subjected to a 50-cycle knee flexion test. The control group used foam of the same thickness. After 10 cycles, the control group curled up at 15°, and after 20 cycles, the control group leaked side leakage. The absorbent patch 1 of this embodiment did not curl up or leak side leakage.

[0056] like Figure 1 As shown, in this embodiment, the length of the projection of the transition region 123 on the plane perpendicular to the thickness direction of the absorbent patch 1 is 5mm to 20mm. When the transition region 123 has a curved surface structure, the angle between the tangent of the curved surface of the transition region 123 and the edge region 122 is 5° to 25°.

[0057] Understandably, the projected length of the transition zone 123 is the length from the central thickened zone 121 to the edge zone 122. The projected length of the transition zone 123 matches the projected length and width of the central thickened zone 121 to properly connect the central thickened zone 121 and the edge zone 122. Furthermore, to ensure a smooth transition between the transition zone 123 and the edge zone 122, the angle between the slope of the transition zone 123 and the edge zone 122 cannot be too large to avoid a steep connection angle causing a discontinuity in the connection.

[0058] Specifically, the length of the projection can be 5mm, 12.5mm, or 20mm. The angle between the inclined plane and the edge area 122 can be 5°, 15°, or 25°.

[0059] like Figure 1 As shown, the absorbent layer 12 in this embodiment is a polyurethane foam layer.

[0060] The porosity of the polyurethane foam layer is 85%–95%, and the pore size is 0.3 mm–2 mm.

[0061] Understandably, the three-dimensional network structure of the polyurethane foam layer, with its open pores, possesses high porosity and excellent capillary action, enabling it to rapidly receive and laterally diffuse large volumes of blood flowing out at high speed, preventing localized blood saturation. Simultaneously, the physical adsorption and temporary storage of blood by the foam layer's pore walls, combined with good compression resilience, maintains a stable liquid storage space under pressure, effectively buffering the initial blood flow impact during hemorrhage and providing uniform liquid distribution to the storage layer 13, thereby preventing lateral leakage and improving overall absorption efficiency.

[0062] Furthermore, the hydrophilicity of the polyurethane foam layer is achieved by adding surfactants or grafting hydrophilic groups. In this embodiment, the contact angle of the polyurethane foam layer is ≤30°. The polyurethane foam layer can achieve an absorption rate ≥8mL / (cm) along the thickness direction of the absorbent patch 1. 2 •s), horizontal capillary pressure difference ≥500Pa.

[0063] Specifically, the porosity of the channel can be 85%, 90%, or 95%. The pore diameter can be 0.3 mm, 1.15 mm, or 2 mm.

[0064] like Figure 1 As shown, the liquid storage layer 13 in this embodiment has capillary channels.

[0065] The capillary channels are filled with absorbent resin particles, which absorb blood and form a gel within the capillary channels.

[0066] Understandably, the capillary channel provides a space for the absorbent resin particles. After absorbing blood, the absorbent resin particles swell and form a gel-like liquid-locking structure, causing the blood entering the capillary channel to form a gel in situ, preventing further blood flow and ultimately locking the blood within the absorbent patch 1.

[0067] like Figure 1 As shown, the liquid storage layer 13 in this embodiment is a core composed of fluff pulp and sodium polyacrylate superabsorbent polymer particles.

[0068] The sodium polyacrylate superabsorbent polymer particles have a particle size of 100μm to 300μm and are uniformly dispersed in the fiber network of fluff pulp.

[0069] Understandably, fluff pulp forms a porous, fluffy framework, with the interfibers accommodating sodium superoxide dismutase (SOD) particles and providing initial diffusion space for blood. The core, composed of fluff pulp and SOD particles, can be manufactured using air-laid or wet-laid processes.

[0070] In this embodiment, the absorbent patch 1, using simulated blood for a liquid absorption simulation test, exhibits an absorption ratio ≥30 times, meaning 1g of material can absorb at least 30g of liquid. The absorbent capacity is ≥50mL. After absorbing blood, it forms a gel, achieving a liquid retention rate ≥90% under 5kPa pressure, meaning no backflow under pressure. The absorption rate along the thickness direction of the absorbent patch 1 is 1–3mL / (cm²). 2 The flow rate is moderately slow (min) to match the temporary storage and release rhythm of the absorption layer 12.

[0071] During a course of bloodletting therapy for varicose veins in the lower extremities, the actual blood loss in a single bloodletting session on the calf (100 cm) is 20 mL to 40 mL. In this embodiment, the capacity of the absorbent layer 12 is 40 mL to 60 mL, the reservoir layer 13 is ≥50 mL, and the total capacity is ≥80 mL, preferably ≥110 mL, providing more than twice the safety margin in extreme cases. Compared to the absorbent capacity of equal-thickness foam in the prior art, which is only 15 mL to 25 mL, the absorbent capacity of the simply thickened type can reach 40 mL to 50 mL, but the actual effective absorption is lower due to overflow and side leakage.

[0072] Specifically, the particle size of the water-absorbing resin particles can be 100μm, 200μm, or 300μm.

[0073] In this embodiment, the liquid storage layer 13 is provided with non-woven fabric wrapping layers on both sides.

[0074] Understandably, to prevent the absorbent resin particles from leaking from the reservoir layer 13, the reservoir layer 13 in this embodiment is provided with non-woven fabric wrapping layers on both sides. The non-woven fabric wrapping layers allow blood to pass through but prevent the absorbent resin particles from passing through, thus sealing the absorbent resin particles within the capillary channels.

[0075] like Figure 1 As shown, the thickness of the liquid storage layer 13 in this embodiment is w, which satisfies: 2mm≤w≤5mm.

[0076] Understandably, the thickness of the liquid storage layer 13 needs to be compatible with the thickness of the absorption layer 12. The thickness of the liquid storage layer 13 should not be too thick to affect the volume of the absorbent patch 1, nor should it be too thin to lock and store all the blood absorbed by the absorption layer 12.

[0077] Specifically, the thickness w of the liquid storage layer 13 can be 2 mm, 3.5 mm, or 5 mm.

[0078] like Figure 1 As shown, the absorbent patch 1 for bloodletting in this embodiment also includes a backing layer 14.

[0079] The backing layer 14 is located on the side of the liquid storage layer 13 away from the absorbent layer 12. The backing layer 14 has a microporous structure and is used to prevent blood leakage and allow water vapor to pass through.

[0080] Understandably, the backing layer 14 is used to prevent blood absorbed by the absorbent patch 1 from leaking into the external environment and to allow water vapor to pass through in order to maintain the breathability of the patient's skin at the absorbent patch 1 and reduce the risk of skin maceration.

[0081] Specifically, the backing layer 14 is made of polyurethane (PU) waterproof and breathable film with a thickness of 0.02 mm to 0.05 mm. In this embodiment, the backing layer 14 has a microporous structure with a pore size of 0.1 μm to 0.5 μm.

[0082] In this embodiment, the water vapor transmission rate (MVTR) of the backing layer 14 is ≥1000 g / (m 2 •24h), hydrostatic pressure ≥20kPa. The upper surface of the backing layer 14 is fixedly connected to the side of the liquid storage layer 13 away from the absorption layer 12 by hot melt adhesive or ultrasonic welding. The edge of the backing layer 14 and the edge of the flow guiding layer 11 can overlap or be formed into one piece by heat sealing.

[0083] In this embodiment, the through hole is a cylindrical hole.

[0084] Understandably, the uniform cross-section of the cylindrical hole allows blood to pass through quickly and be directed toward the absorbent layer 12.

[0085] In this embodiment, the through hole of the flow guiding layer 11 is a conical hole; along the thickness direction of the liquid absorbent patch 1 and toward the absorbent layer 12, the cross-sectional area of ​​the conical hole gradually increases.

[0086] Understandably, the conical orifice gradually increases in cross-section along the flow guide layer 11 toward the absorption layer 12, which is more conducive to the flow of blood toward the absorption layer 12 under a certain blood flow rate.

[0087] like Figure 1 As shown, the guide layer 11 in this embodiment includes a central guide area 111 and an adhesive area 112.

[0088] The adhesive area 112 is arranged around the central guide area 111, and the guide layer 11 is provided with a first release film 15. The first release film 15 is peelably attached to the adhesive area 112.

[0089] Understandably, in order to protect the cleanliness of the through-holes in the central guide zone 111, this embodiment covers the guide layer 11 with a first release film 15, and provides an adhesive area 112 around the central guide zone 111. The portion of the first release film 15 relative to the adhesive area 112 can be fixed to the adhesive area 112, ensuring the adhesion of the first release film 15 to the guide layer 11. The adhesive area 112 is an annular region.

[0090] Specifically, the pasting area 112 is made of non-woven fabric substrate (basic weight 30-40 g / m²). 2 35g / m 2 It consists of a medical pressure-sensitive adhesive coated on a substrate. The pressure-sensitive adhesive can be medical-grade silicone gel, which has the characteristics of low allergenicity, easy removal, and certain adhesion to moist skin. The total thickness of the adhesive area 112 can be 0.08mm to 0.15mm.

[0091] The first release film 15 is made of glassine paper or PET (Polyethylene Terephthalate) film coated with silicone oil, with a thickness of 0.05 mm to 0.1 mm and a release force of 5 g / cm to 15 g / cm.

[0092] Before use, the silicone oil side of the first release film 15 and the pressure-sensitive adhesive side of the adhesive area 112 can be peeled off and bonded together.

[0093] In practical applications, ordinary gauze adheres to blood clots, causing severe pain during removal, and scores 5.2 on the Visual Analogue Scale (VAS). In this embodiment, the drainage layer 11 uses a perforated PE membrane with a pore size of 0.5mm–1.5mm and an open area ratio of 20%–35%. The drainage layer 11 physically isolates the wound, with a peel force ≤0.1N / cm, compared to 0.5–1.5N / cm for ordinary gauze, resulting in painless removal and a VAS score of 0.8, significantly reducing patient pain.

[0094] The absorbent patch 1 in this embodiment is easy to operate and reduces labor intensity. The application time is 10 to 15 seconds, while traditional dressings require 60 to 90 seconds, reducing the labor intensity of medical staff by more than 80%.

[0095] like Figure 1 and Figure 2As shown, when the absorbent patch 1 is applied to the instep, the backing layer 14 is further provided with an adhesive layer 18 and a second release film 16 on the side opposite to the liquid storage layer 13.

[0096] The second release film 16 is located on the outside of the adhesive layer 18, and the second release film 16 is peelably adhered to the pressure-sensitive adhesive surface of the adhesive layer 18. When applying the absorbent patch 1 to the instep, the second release film 16 is peeled off, the adhesive layer 18 is aligned with the instep, and the patch is pressed and applied.

[0097] like Figure 3 and Figure 4 As shown, the absorbent patch 1 for bloodletting in this embodiment also includes a wrapping tape 17.

[0098] The flow guiding layer 11, the absorption layer 12 and the liquid storage layer 13 are stacked and enclosed to form a ring structure, and the winding strip 17 is disposed at both ends of the ring structure.

[0099] Understandably, when wound 101 is located on the lower leg 100, the absorbent patch 1 is placed on the outside of the lower leg 100. The drainage layer 11, the absorbent layer 12, and the reservoir layer 13 form a ring structure and are applied towards the lower side of the wound 101. The wrapping tape 17 is located at both ends of the ring structure. The wrapping tape 17 can wrap around the lower leg 100 to fix the absorbent patch 1 to the lower leg 100. The thickness direction of the absorbent patch 1 is perpendicular to the lower leg 100, which is beneficial for absorbing blood left on the wound 101 on the lower leg 100.

[0100] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An absorbent patch for bloodletting, characterized in that, include: A drainage layer is positioned facing the wound surface and has multiple through-holes penetrating the drainage layer, which are used to collect blood flowing out of the wound surface. An absorbent layer is disposed on the side of the drainage layer opposite to the wound surface. The absorbent layer has three-dimensional interconnected channels, which are connected to the through holes. The absorbent layer includes a central thickened area and an edge area surrounding the central thickened area. The thickness of the central thickened area is greater than the thickness of the edge area. A reservoir layer is located on the side of the absorbent layer opposite to the guide layer, and is used to absorb blood and form a gel.

2. The absorbent patch for bloodletting according to claim 1, characterized in that, The absorption layer further includes a transition region; The transition zone is located between the central thickened zone and the edge zone, and the transition zone has a curved surface structure or a stepped structure.

3. The absorbent patch for bloodletting according to claim 2, characterized in that, The thickness of the central thickened area is h1, and the thickness of the edge area is h2, satisfying: 8mm≤h1≤15mm, 2mm≤h2≤5mm; And / or, the projection of the central thickened area onto a plane perpendicular to the thickness direction of the absorbent patch has a length of 5mm to 11mm along the length direction of the absorbent patch and a length of 3mm to 6mm along the width direction of the absorbent patch. And / or, the thickness of the edge regions is the same; And / or, the length of the projection of the transition zone onto a plane perpendicular to the thickness direction of the absorbent patch is 5mm to 20mm, and in the case where the transition zone has a curved surface structure, the angle between the tangent along the curved surface of the transition zone and the edge zone is 5° to 25°.

4. The absorbent patch for bloodletting according to claim 1, characterized in that, The absorbent layer is a polyurethane foam layer; The porosity of the channels in the polyurethane foam layer is 85% to 95%, and the pore diameter is 0.3 mm to 2 mm.

5. The absorbent patch for bloodletting according to claim 1, characterized in that, The liquid storage layer has capillary channels; The capillary channel is filled with absorbent resin particles, which absorb blood and form a gel within the capillary channel.

6. The absorbent patch for bloodletting according to claim 5, characterized in that, The liquid storage layer is a core composed of fluff pulp and sodium polyacrylate superabsorbent polymer particles; The sodium polyacrylate superabsorbent polymer particles have a particle size of 100μm to 300μm and are uniformly dispersed in the fiber network of the fluff pulp.

7. The absorbent patch for bloodletting according to claim 5, characterized in that, The liquid storage layer is wrapped with non-woven fabric on both sides; And / or, the thickness of the liquid storage layer is w, which satisfies: 2mm≤w≤5mm.

8. The absorbent patch for bloodletting according to any one of claims 1 to 7, characterized in that, Also includes: Backing layer; The backing layer is located on the side of the liquid storage layer away from the absorbent layer. The backing layer has a microporous structure and is used to prevent blood leakage and allow water vapor to pass through. And / or, the guide layer includes a central guide area and an adhesive area; The adhesive area is arranged around the central guide area, and the guide layer is provided with a first release film, which is peelably attached to the adhesive area.

9. The absorbent patch for bloodletting according to claim 1, characterized in that, The through hole is a cylindrical hole; And / or, the through holes of the flow guiding layer are conical holes; along the thickness direction of the absorbent patch and toward the absorbent layer, the cross-sectional area of ​​the conical holes gradually increases.

10. The absorbent patch for bloodletting according to any one of claims 1 to 7, characterized in that, Also includes: Wrapping tape; The flow guiding layer, the absorption layer, and the liquid storage layer are stacked and enclosed to form a ring structure, and the winding strips are respectively disposed at both ends of the ring structure.

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