Negative pressure color change indication dressing

Abstract

The utility model relates to a negative-pressure color-changing indication dressing. The negative-pressure color-changing indication dressing is provided with a first polyurethane film layer, a color-changing indication layer, a super liquid absorption layer, a hot melt adhesive layer, a 3D eyelet fabric layer, a perforated adhesive layer, a perforated second polyurethane film layer and a perforated silica gel layer which are sequentially stacked from top to bottom, wherein the color-changing indication layer is an annular sheet layer with a hollow middle part, and a substance which changes color when encountering liquid is arranged in the color-changing indication layer. The color-changing indicating layer with the hollow middle is used, so that the liquid absorption condition of the dressing can be conveniently and quickly observed, the dressing is prompted to be replaced in time, and the sealing performance of a negative pressure system is ensured.

Description

Technical Field

[0001] This utility model relates to the field of medical dressings, and in particular to a negative pressure color-changing indicator dressing. Background Technology

[0002] A negative pressure wound therapy system is a treatment system for continuous negative pressure drainage of superficial wounds and ulcers. It includes a negative pressure device, negative pressure dressing, sealing strips, and drainage tubes. The sealing strips are used to adhere the dressing to the skin. Its working principle is that in a closed environment, the negative pressure device operates to draw suction, creating a negative pressure below atmospheric pressure at the dressing site through the drainage tubes. This removes excess exudate from the wound, promotes angiogenesis, encourages granulation tissue growth, provides a protective barrier, reduces the number of bacteria in the wound, and lowers the chance of infection. The negative pressure setting range for the negative pressure device is 50–200 mmHg, with a commonly used therapeutic negative pressure of 125 mmHg.

[0003] CN117137725A discloses a negative pressure drainage dressing, comprising a suction cup, a highly permeable membrane layer, a water-resistant and breathable membrane, an absorbent layer, an isolation layer, a perforated silicone gel patch, and a release film layer, which are sequentially stacked and connected. The negative pressure drainage dressing can improve the evaporation efficiency of exudate, help keep the wound dry and reduce wound pressure, reduce the frequency of dressing changes, promote wound healing, improve treatment efficacy, and reduce the risk of wound infection.

[0004] CN113425501A discloses a negative pressure drainage wound dressing and a negative pressure drainage wound dressing device. During the free foaming process of the polyurethane polymer, it closely fits the wound cavity, ensuring good adhesion between the sponge and the edge of the wound cavity without voids or dead spaces, thus guaranteeing good fit. Under the action of negative pressure, it can better stimulate the proliferation of granulation tissue. At the same time, growth factors and antibacterial factors are added to the polymer design. During the free foaming process of the polymer, the antibacterial factors are freely dispersed into the foam sponge, which improves the product's anti-infection ability and greatly reduces the risk of wound infection and deterioration.

[0005] The replacement of negative pressure dressings depends on the amount of secretions (exudate). For wounds with more secretions (exudate), medical staff will frequently pause the negative pressure therapy device and remove the dressing in order to judge the absorption of the dressing and the healing status of the wound. Since the negative pressure wound therapy system has very high requirements for the sealing of the entire system, disposable sealing strips must be replaced afterwards to achieve a new seal.

[0006] In summary, how to promptly remind patients to change dressings, reduce the frequency of dressing removal, and ensure the airtightness of the negative pressure system has become one of the urgent problems to be solved in this field. Utility Model Content

[0007] To solve the above-mentioned technical problems, this utility model provides a negative pressure color-changing indicator dressing. By setting a color-changing indicator layer between the first polyurethane film layer and the superabsorbent layer, the liquid absorption of the dressing can be observed conveniently and quickly. After the wound exudate enters the color-changing indicator layer, the color of the color-changing indicator layer changes color, thereby reminding the user to change the dressing in time, and ensuring the sealing of the negative pressure system.

[0008] In a first aspect, this utility model provides a negative pressure color-changing indicator dressing, wherein the negative pressure color-changing indicator dressing is provided in layers from top to bottom, including a first polyurethane film layer, a color-changing indicator layer, a super absorbent liquid layer, a hot melt adhesive layer, a 3D mesh fabric layer, a perforated adhesive layer, a perforated second polyurethane film layer, and a perforated silicone gel layer.

[0009] The color-changing indicator layer is a ring-shaped sheet with a hollow center, and contains a substance that changes color when it comes into contact with liquid.

[0010] The color-changing indicator layer used in this invention is located between the first polyurethane film layer and the dressing core (including a superabsorbent layer, a hot melt adhesive layer, and a 3D mesh fabric layer), with its outermost edge flush with the superabsorbent layer of the dressing core. When using the negative pressure color-changing indicator dressing provided by this invention, the release paper layer needs to be peeled off, and the silicone gel layer adheres to the skin. To allow wound exudate to flow into the dressing core, an adhesive layer is used to connect the dressing core. However, the silicone gel layer cannot directly bond with the adhesive layer; therefore, this invention adds a second polyurethane film layer as a medium to connect the silicone gel layer and the adhesive layer.

[0011] As the exudate flows from the center of the dressing outwards, it seeps into the superabsorbent layer through the 3D mesh fabric. The substances inside the superabsorbent layer absorb and lock in the exudate. When the superabsorbent layer is saturated, the exudate reaches the color-changing indicator layer and changes color. The user can directly observe the color change of the color-changing indicator layer through the transparent first polyurethane film layer, thus reminding medical staff to change the dressing.

[0012] To ensure that the negative pressure color-changing indicator dressing has excellent liquid absorption, this invention uses perforations in the adhesive layer, the second polyurethane film layer, and the silicone gel layer to facilitate liquid penetration into the dressing core.

[0013] Preferably, the color-changing indicator layer is an annular sheet with a central hollow layer formed around the superabsorbent layer.

[0014] Preferably, the annular width of the color-changing indicator layer is 1 to 1.5 cm (for example, it can be 1 cm, 1.1 cm, 1.2 cm, 1.3 cm, 1.4 cm or 1.5 cm, etc.).

[0015] If the width of the annular sheet in this invention is too wide or too narrow, the color-changing indicator layer will change color too early or too late, affecting the dressing replacement time and causing dressing waste.

[0016] Preferably, the material of the color-changing indicator layer includes any one of non-woven fabric, knitted fabric, or woven fabric.

[0017] Preferably, the substance that changes color upon contact with liquid includes any one of a hygroscopic agent, a material impregnation color developer, or a capsule-encapsulated color-changing agent.

[0018] This invention allows for the addition of substances that can physically and chemically react with the seepage liquid to the color-changing indicator layer. The physical reaction mainly involves coating the material with a hygroscopic agent. When the ambient humidity increases, the hygroscopic agent's hygroscopic capacity increases, absorbing water molecules from the environment, leading to a change in the molecular structure of the color-changing agent, thereby altering the absorption spectrum characteristics of the pigment and causing it to exhibit different colors. The chemical reaction mainly involves impregnating the material with a color-developing agent, such as bromophenol blue. When bromophenol blue comes into contact with water, an acid-base neutralization reaction occurs, changing the molecular structure of the bromophenol blue and altering its absorption spectrum characteristics, thus exhibiting different colors. In addition, there are some special water-sensitive color-changing pigments, such as those using sealed capsules to encapsulate the color-changing agent. When exposed to water, the capsules rupture, and the color-changing agent reacts with the water, thereby changing the color of the pigment.

[0019] Preferably, the first polyurethane film layer, the color-changing indicator layer, the superabsorbent layer, the hot melt adhesive layer, the 3D mesh fabric layer, the adhesive layer, the second polyurethane film layer, and the silicone gel layer are sheet-like structures.

[0020] Preferably, the surface areas of the color-changing indicator layer, the superabsorbent layer, the hot melt adhesive layer, and the 3D mesh fabric layer are all smaller than the surface area of ​​the first polyurethane film layer.

[0021] The surface area of ​​the first polyurethane film layer used in this invention is larger than that of the color-changing indicator layer, the superabsorbent layer, the hot melt adhesive layer, and the 3D mesh fabric layer. The first polyurethane film layer is partially connected to the adhesive layer, thereby fixing the color-changing indicator layer, the superabsorbent layer, the hot melt adhesive layer, and the 3D mesh fabric layer inside the first polyurethane film layer and the adhesive layer, that is, inside the dressing provided by this invention. When the dressing core absorbs liquid, it can still maintain good sealing performance and is suitable as a dressing for negative pressure wound therapy systems.

[0022] Preferably, the thickness of the first polyurethane film layer is 25–40 μm (e.g., 25 μm, 28 μm, 30 μm, 32 μm, 34 μm, 36 μm, 38 μm, or 40 μm, etc.), the thickness of the color-changing indicator layer is 20–30 μm (e.g., 20 μm, 22 μm, 24 μm, 25 μm, 26 μm, 28 μm, or 30 μm, etc.), the thickness of the superabsorbent layer is 1–2 mm (e.g., 1 mm, 1.2 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.8 mm, or 2 mm, etc.), and the thickness of the hot melt adhesive layer is 5–10 μm (e.g., 5 μm, 6 μm, 7 μm, 7.5 μm, 8 μm, 9 μm, or 10 μm, etc.). The thickness of the 3D mesh fabric layer is 3–3.5 mm (e.g., 3 mm, 3.1 mm, 3.2 mm, 3.3 mm, 3.4 mm, or 3.5 mm, etc.), the thickness of the adhesive layer is 10–15 μm (e.g., 10 μm, 11 μm, 12 μm, 12.5 μm, 13 μm, 14 μm, or 15 μm, etc.), the thickness of the second polyurethane film layer is 25–40 μm (e.g., 25 μm, 28 μm, 30 μm, 32 μm, 34 μm, 36 μm, or 40 μm, etc.), and the thickness of the silicone gel layer is 50–500 μm (e.g., 50 μm, 100 μm, 200 μm, 250 μm, 300 μm, 400 μm, or 500 μm, etc.).

[0023] Preferably, a release paper layer is further provided under the silicone gel layer.

[0024] Preferably, the release paper layer has a folded and tear-off structure.

[0025] Other specific point values ​​within the range of the above values ​​can be selected, and will not be elaborated on here.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] This invention utilizes a hollowed-out color-changing indicator layer. When the superabsorbent layer becomes saturated, the exudate reaches the indicator layer, causing a color change. This allows for convenient and quick observation of the dressing's absorption status, providing timely reminders to replace the dressing and reducing the number of times the dressing needs to be removed. This reduces cumbersome operations and the consumption of sealing strips, ensuring the sealing performance of the negative pressure system. Attached Figure Description

[0028] Figure 1 This is a cross-sectional structural diagram of the negative pressure color-changing indicator dressing of this utility model, wherein 1 is the first polyurethane film layer, 2 is the color-changing indicator layer, 3 is the superabsorbent layer, 4 is the hot melt adhesive layer, 5 is the 3D mesh fabric layer, 6 is the adhesive layer, 7 is the second polyurethane film layer, 8 is the silicone gel layer, and 9 is the release paper layer.

[0029] Figure 2 This is a top view of the negative pressure color-changing indicator dressing of this utility model, wherein 2 is the color-changing indicator layer. Detailed Implementation

[0030] To further illustrate the technical means and effects of this utility model, the following description, in conjunction with embodiments and accompanying drawings, further explains this utility model. It should be understood that the specific embodiments described herein are merely illustrative of this utility model and not intended to limit its scope.

[0031] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, 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 this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0032] Example 1

[0033] This embodiment provides a negative pressure color-changing indicator dressing, the cross-sectional structure of which is as follows: Figure 1 As shown, the negative pressure color-changing indicator dressing is stacked from top to bottom as follows: a first polyurethane film layer 1 with a thickness of 25-40 μm, a color-changing indicator layer 2 with a thickness of 20-30 μm, a superabsorbent liquid layer 3 with a thickness of 1-2 mm, a hot melt adhesive layer 4 with a thickness of 5-10 μm, a 3D mesh fabric layer 5 with a thickness of 3-3.5 mm, a perforated adhesive layer 6 with a thickness of 10-15 μm, a perforated second polyurethane film layer 7 with a thickness of 25-40 μm, and a perforated silicone gel layer 8 with a thickness of 50-500 μm. All of the above structures are sheet structures.

[0034] The color-changing indicator layer 2 is an annular layer with a hollow center formed around the superabsorbent liquid layer 3, containing a substance that changes color upon contact with liquid. The annular width is 1–1.5 cm. The material of the color-changing indicator layer 2 includes any one of non-woven fabric, knitted fabric, or woven fabric. The surface areas of the color-changing indicator layer 2, superabsorbent liquid layer 3, hot melt adhesive layer 4, and 3D mesh fabric layer 5 are all smaller than the surface area of ​​the first polyurethane film layer 1. A release paper layer 9 is also provided under the silicone gel layer 8, which has a folded and tear-off structure.

[0035] Figure 2This is a top view of the negative pressure color-changing indicator dressing provided by this utility model. The color-changing indicator layer 2 is an annular layer with a hollow center formed around the superabsorbent layer 3, and contains a substance that changes color when it comes into contact with liquid. When exudate flows from the center of the dressing core to the surrounding area, after the superabsorbent layer becomes saturated, the exudate reaches the color-changing indicator layer, causing a color change, thus reminding the user to change the dressing.

[0036] Test Example 1

[0037] This test case uses the negative pressure color-changing indicator dressing provided in Example 1, which is installed in a negative pressure wound therapy system. The color-changing indicator layer is impregnated with bromophenol blue. The dressing is applied to the venous ulcer on the leg. The selected dressing core is 1-2 cm larger than the edge of the ulcer. The dressing is sealed with a sealing strip around its perimeter. The drainage tube is connected to the negative pressure therapy device. The negative pressure therapy device is turned on and the negative pressure is maintained at 125 mmHg. After 36 hours, one edge of the color-changing indicator layer 2 begins to turn blue. After 48 hours, the other edge of the color-changing indicator layer 2 begins to turn blue. At this point, the negative pressure therapy device is stopped, the sealing strip is removed, and the dressing is replaced.

[0038] In summary, this utility model provides a negative pressure color-changing indicator dressing. By using a hollowed-out color-changing indicator layer, when the superabsorbent layer is saturated, the exudate reaches the color-changing indicator layer and changes color, allowing for convenient and quick observation of the dressing's absorption status. This provides timely reminders to replace the dressing, reducing the number of times the dressing needs to be removed, thereby reducing cumbersome operations and the consumption of sealing strips, and ensuring the sealing performance of the negative pressure system.

[0039] The applicant declares that the above description is only a specific embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present utility model fall within the protection and disclosure scope of the present utility model.

Claims

1. A negative pressure color change indicating dressing, characterized in that, The negative pressure color-changing indicator dressing is arranged in layers from top to bottom as follows: a first polyurethane film layer (1), a color-changing indicator layer (2), a super absorbent liquid layer (3), a hot melt adhesive layer (4), a 3D mesh fabric layer (5), a perforated adhesive layer (6), a perforated second polyurethane film layer (7), and a perforated silicone gel layer (8). The color-changing indicator layer (2) is a ring-shaped sheet with a hollow center, and contains a substance that changes color when it comes into contact with liquid.

2. The negative pressure color-changing indicator dressing of claim 1, wherein, The color-changing indicator layer (2) is an annular sheet with a hollow center formed around the superabsorbent layer (3).

3. The negative pressure color-changing indicator dressing of claim 1, wherein, The annular width of the color-changing indicator layer (2) is 1 to 1.5 cm.

4. The negative pressure color-changing indicator dressing of claim 1, wherein, The material of the color-changing indicator layer (2) includes any one of non-woven fabric, knitted fabric or woven fabric.

5. The negative pressure color-changing indicator dressing of claim 1, wherein, The substance that changes color upon contact with liquid includes any one of the following: a hygroscopic agent, a material impregnation color developer, or a capsule-encapsulated color-changing agent.

6. The negative pressure color-changing indicator dressing of claim 1, wherein, The first polyurethane film layer (1), the color-changing indicator layer (2), the superabsorbent layer (3), the hot melt adhesive layer (4), the 3D mesh fabric layer (5), the adhesive layer (6), the second polyurethane film layer (7), and the silicone gel layer (8) are sheet structures.

7. The negative pressure color-changing indicator dressing of claim 1, wherein, The surface areas of the color-changing indicator layer (2), the superabsorbent layer (3), the hot melt adhesive layer (4), and the 3D mesh fabric layer (5) are all smaller than the surface area of ​​the first polyurethane film layer (1).

8. The negative pressure color-changing indicator dressing of claim 1, wherein, The thickness of the first polyurethane film layer (1) is 25-40 μm, the thickness of the color-changing indicator layer (2) is 20-30 μm, the thickness of the superabsorbent layer (3) is 1-2 mm, the thickness of the hot melt adhesive layer (4) is 5-10 μm, the thickness of the 3D mesh fabric layer (5) is 3-3.5 mm, the thickness of the adhesive layer (6) is 10-15 μm, the thickness of the second polyurethane film layer (7) is 25-40 μm, and the thickness of the silicone gel layer (8) is 50-500 μm.

9. The negative pressure color-changing indicator dressing of claim 1, wherein, A release paper layer (9) is also provided under the silicone gel layer (8).

10. The negative pressure color-changing indicator dressing of claim 9, wherein, The release paper layer (9) has a folded and tear-off structure.

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