Wound dressing with body liquid saturation degree visualization function and preparation method of indication layer used by wound dressing

Abstract

The invention belongs to the technical field of medical wound nursing materials, and discloses a wound dressing with a body liquid saturation degree visualization function and a preparation method of an indication layer used by the wound dressing, and the wound dressing with the body liquid saturation degree visualization function is obtained by sequentially compounding the indication layer, a liquid absorption layer and a contact layer, the indicating layer is a liquid triggered transparency change film; the liquid absorption layer is made of polyurethane foam; the contact layer is a poly-silicone film, and a plurality of liquid permeable holes are formed in the poly-silicone film; the preparation method of the liquid-triggered transparency change film comprises the following steps: uniformly mixing a branched polyethyleneimine colloidal solution and an anionic polyurethane solution to obtain a nano-micelle dispersion liquid, and uniformly spraying the nano-micelle dispersion liquid on a transparent polyurethane film to prepare the liquid-triggered transparency change film. Visual indication of the liquid absorption saturation of the wound dressing is achieved, medical staff or a patient can be visually reminded to replace the dressing in time, and application is more flexible.

Description

Technical Field

[0001] The invention belongs to the technical field of medical wound care materials, and relates to a wound dressing with a body liquid saturation visualization function and a preparation method of an indicator layer used therefor. Background Art

[0002] After skin injury, the wound surface will produce biological fluids such as blood and exudate, which contain a large amount of water and solid substances, such as necrotic cells and proteins. Since solid substances are difficult to be effectively absorbed by ordinary dressings, they are easy to accumulate in the wound, causing bacterial infection, delaying wound healing, and even causing serious tissue damage. Therefore, how to effectively manage wound exudate has become a key issue in clinical care.

[0003] At present, there are some wound dressings with exudate management functions on the market, such as foam dressings, hydrogel dressings, etc. However, these dressings have obvious limitations in practical applications. Medical staff usually rely on experience and visual observation to judge the liquid saturation of the dressing, and it is difficult to accurately determine the best time to change the dressing. This uncertainty may not only lead to waste of dressings, but also increase the risk of wound infection and affect the treatment effect.

[0004] To solve this problem, the prior art has proposed some improvement solutions. For example, the patent with publication number CN205598094U discloses a pressure-visible wound exudate management dressing, which absorbs wound exudate and senses dressing pressure, so that medical staff can judge whether the liquid absorption of the dressing has reached saturation based on the pressure change. However, this solution has obvious defects: it needs to rely on circuit connection to achieve pressure sensing, which not only increases the complexity of the dressing, but also limits its flexible application and promotion in actual clinical practice.

[0005] Therefore, it is of great significance to study a wound dressing with a function of visualizing the saturation of the bulk liquid and a preparation method of the indicator layer used therein to solve the above problems. Summary of the invention

[0006] The purpose of the present invention is to solve the problems existing in the prior art and to provide a wound dressing with a function of visualizing the saturation of bulk liquid and a method for preparing an indicator layer used therein.

[0007] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0008] A method for preparing a liquid-triggered transparency-changing film comprises the following steps: uniformly mixing a branched polyethyleneimine colloid solution with an anionic polyurethane solution to obtain a nano-micelle dispersion, and then uniformly spraying the nano-micelle dispersion on a transparent polyurethane film to prepare the liquid-triggered transparency-changing film.

[0009] Branched polyethyleneimine has multiple branches on its molecular chain, which makes the polymer have higher solubility and reactivity. In addition, each branch end of branched polyethyleneimine contains an amino group, which is easily protonated in the solution to make it positively charged. This cationic property enables it to form a stable branched polyethyleneimine / polyurethane particle nano-micelle dispersion with anionic polyurethane.

[0010] When the branched polyethyleneimine colloidal solution is used alone, it cannot form a stable micelle dispersion. The present invention uses anionic polyurethane, which is mixed with branched polyethyleneimine to form a stable branched polyethyleneimine / polyurethane micelle dispersion through electrostatic interaction. The formed particles are branched polyethyleneimine / polyurethane particles, and they can be attached to the polyurethane film.

[0011] As the preferred technical solution:

[0012] In the method for preparing a liquid-triggered transparency-changing film, the content of the branched polyethyleneimine colloid in the nano-micelle dispersion is 5-25wt%, and the content of the anionic polyurethane is 15-45wt%.

[0013] In the method for preparing a liquid-triggered transparency-changing film as described above, the thickness of the transparent polyurethane film is 0.5 to 1.5 mm, and the thickness of the particle layer sprayed on the transparent polyurethane film is 10 to 50 μm.

[0014] In the method for preparing a liquid-triggered transparency-changing film as described above, the nanomicelle dispersion is sprayed using an air brush spraying device.

[0015] In the method for preparing a liquid-triggered transparency-changing film as described above, the spraying pressure is 0.5 to 3 Bar, the spraying distance is 5 to 25 cm, the spraying time is 5 to 20 s, and the spraying amount of the nanomicelle dispersion is 10 to 50 μL.

[0016] In the method for preparing a liquid-triggered transparency-changing film as described above, the nano-micelle dispersion is uniformly sprayed on the transparent polyurethane film and then placed at room temperature to dry naturally for 30 to 120 minutes.

[0017] The present invention also provides a wound dressing with a function of visualizing the body liquid saturation, which is obtained by compounding an indicator layer, a liquid absorption layer and a contact layer in sequence;

[0018] The indicator layer is a liquid-triggered transparency-changing film prepared by any of the methods described above; the liquid-absorbing layer is polyurethane foam having a three-dimensional interconnected pore structure for absorbing exudate; the contact layer is a polysilicone film having a plurality of liquid-permeable holes arranged thereon, which is in direct contact with the wound, provides adhesion and can be used to guide the rapid penetration of exudate.

[0019] The liquid intrusion causes the indicator layer to change in transparency, indicating the liquid saturation of the dressing. When the liquid absorption of the liquid-absorbing layer reaches saturation, excess liquid will invade the indicator layer, causing its transparency to change, thus prompting the dressing to be changed.

[0020] As the preferred technical solution:

[0021] In the wound dressing with the function of visualizing the body liquid saturation as described above, the indicating layer, the liquid absorbing layer and the contact layer are laminated by edge hot pressing or bonding with a polyurethane adhesive.

[0022] Edge hot pressing: stack the three layers and put them into a hot press. Apply a temperature of 100-140°C and a pressure of 1000-3000Pa to the edges with a width of 5-10mm to soften and bond them.

[0023] Bonding: Polyurethane adhesive is evenly applied to the surfaces of the indicator layer, liquid absorption layer and contact layer within a width of 5 to 10 mm around the edges, and then pressed (pressure range 500 to 1000 Pa) to fix them after stacking, and wait for the adhesive to solidify.

[0024] As described above, in a wound dressing with the function of visualizing the body liquid saturation, the thickness of the indicator layer is 0.51-1.55 mm, the thickness of the liquid absorption layer is 5-10 mm, and the thickness of the contact layer is 0.5-1 mm, and the thickness of each layer does not include the thickness of the edge width when compounded.

[0025] Invention mechanism:

[0026] In the preparation method of a liquid-triggered transparency-changing film of the present invention, a particle layer composed of branched polyethyleneimine / polyurethane particle nano-micelles is formed by spraying on a transparent polyurethane film, and the spaces between the particles are filled with air. Since the refractive index of air is 1.0 and the refractive index of polyurethane is 1.4-1.5, the polyurethane film as a whole is in a scattering state, and the polyurethane film is non-transparent. When liquid (wound exudate) intrudes, it fills the gaps between the particles. Since the refractive index of water is 1.33, the refractive index of wound exudate is between 1.33 and 1.35, which is closer to the refractive index of polyurethane, so the indicator layer is in a transparent state.

[0027] After a wound dressing having a body liquid saturation visualization function, which is composed of a liquid-triggered transparency-changing film prepared in the present invention as an indicator layer, is applied to the wound, exudate generated by the wound enters the absorption layer through the liquid-permeable holes on the contact layer and is absorbed; when the liquid absorption of the absorption layer of the dressing reaches saturation, excess liquid invades the indicator layer, thereby filling the gaps between the particles, making the indicator layer transparent, thereby reminding the dressing to be replaced.

[0028] Beneficial effects:

[0029] The present invention sprays a branched polyethyleneimine colloid solution and a polyurethane solution on a transparent polyurethane film to form a micron-sized particle layer, so that the film is non-transparent and presents a scattering state when not in contact with liquid, and becomes transparent when liquid invades. The structure realizes a visual indication of the liquid absorption saturation of the wound dressing, and can intuitively remind medical staff or patients to change the dressing in time, thereby reasonably arranging the replacement time, and avoiding wound infection or other complications caused by untimely replacement, improving the convenience and safety of wound care, improving nursing work efficiency, reducing nursing costs, and being more flexible in actual clinical practice, which also makes it have important clinical application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the structure of the wound dressing with the function of visualizing the saturation of the main body liquid of the present invention;

[0031] Figure 2 Schematic diagram of the wound dressing with the function of visualizing the saturation of the main body liquid before and after liquid absorption saturation; in the figure, a is a schematic diagram of the wound dressing with the function of visualizing the saturation of the main body liquid before liquid absorption saturation and being non-transparent, and b is a schematic diagram of the wound dressing with the function of visualizing the saturation of the main body liquid after liquid absorption saturation and being transparent;

[0032] Figure 3 It is a top view of the wound dressing with body liquid saturation visualization function of the present invention;

[0033] Figure 4 This is a bottom view of the wound dressing with body liquid saturation visualization function of the present invention;

[0034] Figure 5 This is a schematic diagram of the transmittance change of the wound dressing with the function of visualizing the saturation of the bulk liquid prepared in Example 1 of the present invention when it is in a non-transparent and transparent state;

[0035] Among them, 1 is the indicator layer, 2 is the liquid absorption layer, 3 is the contact layer, and 4 is the liquid permeable hole. DETAILED DESCRIPTION

[0036] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0037] In order to ensure that the properties of the materials used in each embodiment and comparative example are fully disclosed, the manufacturers and brands of the materials are indicated, and products of other manufacturers and brands that meet the requirements of the present invention are also feasible.

[0038] The testing methods of the relevant performance indicators in the following embodiments and comparative examples are as follows:

[0039] Transmittance: The wound dressings with bulk liquid saturation visualization function prepared in each embodiment were cut into 5 mm × 15 mm sizes as sample A, and then sample A was placed in a cuvette and fixed, and then the cuvette was placed in a spectrophotometer (TV-1901) and its absorbance OD in the wavelength range of 400 to 800 nm was tested. 1 and compared with the absorbance OD of the blank cuvette in the wavelength range of 400-800nm 2 The transmittance of sample A is calculated by the calculation formula of transmittance T.

[0040] Then, the sample was soaked in deionized water for 30 seconds to obtain a wetted liquid-triggered transparency change film, which was then cut into a size of 5 mm × 15 mm as sample B. Sample B was placed in a cuvette and fixed, and then the cuvette was placed in a spectrophotometer (TV-1901) to test its absorbance OD in the wavelength range of 400 to 800 nm. 1 and compared with the absorbance OD of the blank cuvette in the wavelength range of 400-800nm 2 The transmittance of sample B is calculated by the calculation formula of transmittance T.

[0041] The calculation formula of transmittance T is:

[0042] The following is the preparation process of the anionic polyurethane used in each embodiment:

[0043] Under nitrogen protection, 32 ml of isophorone diisocyanate (manufacturer: Ron Reagent, brand number: R018211) and 100 g of polyethylene glycol 400 (manufacturer: Shanghai Yuanye Biotechnology Co., Ltd., product number: S30185) were first polymerized at 110°C for 4 hours to generate long molecular chain segments, and then 6.8 g of 2,2-dihydroxymethylpropionic acid (manufacturer: Shanghai Yuanye Biotechnology Co., Ltd., product number: S24027) was added thereto to allow the hydroxyl group to react with the remaining isocyanate in the solution to form additional molecular chains, and finally 0.044 mol of triethylamine (manufacturer: Shanghai Mairui Biochemical Technology Co., Ltd., product number: M03649) was added to the system to neutralize the carboxylic acid, thereby converting the waterborne polyurethane into an anionic type to obtain anionic polyurethane.

[0044] Example 1

[0045] A method for preparing a liquid-triggered transparency-changing film, comprising the following steps:

[0046] (1) mixing a branched polyethyleneimine colloid solution (concentration of 20 mg / ml, solvent of deionized water, manufacturer of branched polyethyleneimine colloid is Beijing Huawei Ruike Chemical Technology Co., Ltd., brand HWG62344) with an anionic polyurethane solution (concentration of 15 wt %, solvent of deionized water, anionic polyurethane is the anionic polyurethane prepared as described above), and then dispersing the mixture at a speed of 8000 rpm for 10 min using a homogenizer to obtain a nanomicelle dispersion; wherein the content of the branched polyethyleneimine colloid in the nanomicelle dispersion is 0.5 wt %, and the content of the anionic polyurethane is 15 wt %;

[0047] (2) The nanomicelle dispersion obtained in step (1) was evenly sprayed on a transparent polyurethane film with a thickness of 0.5 mm (manufacturer: Guangzhou Hongxin New Material Technology Co., Ltd., brand: HXE585) using an air brush spray device, and dried at 22° C. for 30 min to obtain a liquid-triggered transparency change film; wherein the spraying pressure was 1.5 Bar, the spraying distance was 15 cm, the spraying time was 10 s, and the spraying amount of the nanomicelle dispersion was 20 μL.

[0048] The thickness of the particle layer sprayed on the transparent polyurethane film in the liquid-triggered transparency change film finally prepared was 15 μm.

[0049] A wound dressing with a function of visualizing the body fluid saturation, such as Figure 1 As shown, it is composed of an indicator layer 1, a liquid absorbing layer 2 and a contact layer 3;

[0050] The indicator layer 1 is the liquid-triggered transparency change film prepared above, with a thickness of 0.515 mm;

[0051] The liquid absorbing layer 2 is polyurethane foam with a thickness of 5 mm;

[0052] The contact layer 3 is a polysilicone film with a plurality of liquid permeable holes 4 (manufacturer is Huizhou Huayang Medical Equipment Co., Ltd., brand name Soft silicone patch), thickness 0.5mm;

[0053] like Figures 2 to 5 As shown, the wound dressing with the function of visualizing the body liquid saturation is in a non-transparent state when not in contact with exudate, with a transmittance of 59.2%; when the exudate invades, it becomes transparent, with a transmittance of 90.91%.

[0054] The specific compounding process of each layer is as follows: polyurethane adhesive (manufacturer is Minnesota Mining Manufacturing Company, brand 5200) is evenly coated on each surface where the liquid-triggered transparency change film, polyurethane foam, and silicone film are bonded within a range of 7 mm on all sides of the edge width, and after stacking, a pressure of 750 Pa is applied to fix it, and the adhesive is cured to obtain a wound dressing with the function of visualizing the saturation of the main body liquid; wherein, during compounding, the granular layer of the liquid-triggered transparency change film is in close contact with one side of the polyurethane foam.

[0055] Example 2

[0056] A method for preparing a liquid-triggered transparency-changing film, comprising the following steps:

[0057] (1) mixing a branched polyethyleneimine colloid solution (concentration of 25 mg / ml, solvent of deionized water, manufacturer of branched polyethyleneimine colloid is Beijing Huawei Ruike Chemical Technology Co., Ltd., brand HWG62344) with an anionic polyurethane solution (concentration of 20 wt %, solvent of deionized water, anionic polyurethane is the anionic polyurethane prepared above), and dispersing the mixture at a speed of 6500 rpm for 7 min using a homogenizer to obtain a nanomicelle dispersion; wherein the content of the branched polyethyleneimine colloid in the nanomicelle dispersion is 1 wt %, and the content of the anionic polyurethane is 20 wt %;

[0058] (2) The nanomicelle dispersion obtained in step (1) was evenly sprayed on a transparent polyurethane film with a thickness of 0.7 mm (manufacturer: Guangzhou Hongxin New Material Technology Co., Ltd., brand: HXE585) using an air brush spray device, and dried at 22° C. for 80 min to obtain a liquid-triggered transparency change film; wherein the spraying pressure was 0.5 Bar, the spraying distance was 5 cm, the spraying time was 5 s, and the spraying amount of the nanomicelle dispersion was 10 μL.

[0059] The thickness of the particle layer sprayed on the transparent polyurethane film in the liquid-triggered transparency change film finally prepared was 10 μm.

[0060] A wound dressing with a function of visualizing the body liquid saturation, comprising an indicator layer, a liquid absorption layer and a contact layer;

[0061] The indicator layer is the liquid-triggered transparency-changing film prepared above, with a thickness of 0.71 mm;

[0062] The liquid-absorbing layer is polyurethane foam with a thickness of 7 mm;

[0063] The contact layer is a polysilicone film with multiple liquid permeable holes (manufacturer: Huizhou Huayang Medical Device Co., Ltd., brand name: Soft silicone patch), thickness 0.65mm;

[0064] The wound dressing with the function of visualizing the body liquid saturation is in a non-transparent state when not in contact with exudate, with a transmittance of 55%; when exudate invades, it becomes transparent, with a transmittance of 89.32%.

[0065] The specific compounding process of each layer is as follows: the liquid-triggered transparency-changing film, polyurethane foam, and silicone film are stacked in sequence, and then placed in a hot press, and a pressure of 2000Pa is applied to the edges of the film within a width of 8mm at a temperature of 120°C to soften and bond them, thereby obtaining a wound dressing with the function of visualizing the saturation of the liquid in the body; wherein, during compounding, the granular layer of the liquid-triggered transparency-changing film is in close contact with one side of the polyurethane foam.

[0066] Example 3

[0067] A method for preparing a liquid-triggered transparency-changing film, comprising the following steps:

[0068] (1) mixing a branched polyethyleneimine colloid solution (concentration of 30 mg / ml, solvent of deionized water, manufacturer of branched polyethyleneimine colloid is Beijing Huawei Ruike Chemical Technology Co., Ltd., brand HWG62344) with an anionic polyurethane solution (concentration of 25 wt %, solvent of deionized water, anionic polyurethane is the anionic polyurethane prepared above), and then dispersing the mixture at a speed of 8500 rpm for 10 min using a homogenizer to obtain a nanomicelle dispersion; wherein the content of branched polyethyleneimine colloid in the nanomicelle dispersion is 1.6 wt %, and the content of anionic polyurethane is 25 wt %;

[0069] (2) The nanomicelle dispersion obtained in step (1) was evenly sprayed on a transparent polyurethane film with a thickness of 1 mm (manufacturer: Guangzhou Hongxin New Material Technology Co., Ltd., brand: HXE585) using an air brush spray device, and dried at 22° C. for 120 min to obtain a liquid-triggered transparency change film; wherein the spraying pressure was 3 Bar, the spraying distance was 25 cm, the spraying time was 20 s, and the spraying amount of the nanomicelle dispersion was 50 μL.

[0070] The thickness of the particle layer sprayed on the transparent polyurethane film in the liquid-triggered transparency change film finally prepared is 45 μm.

[0071] A wound dressing with a function of visualizing the body liquid saturation, comprising an indicator layer, a liquid absorption layer and a contact layer;

[0072] The indicating layer is the liquid-triggered transparency-changing film prepared above, with a thickness of 1.045 mm;

[0073] The liquid-absorbing layer is polyurethane foam with a thickness of 7 mm;

[0074] The contact layer is a polysilicone film with multiple liquid permeable holes (manufacturer: Huizhou Huayang Medical Device Co., Ltd., brand: Soft silicone patch), thickness 0.75mm;

[0075] The wound dressing with the function of visualizing the body liquid saturation is in a non-transparent state when not in contact with exudate, with a transmittance of 50%; when exudate invades, it becomes transparent, with a transmittance of 83.75%.

[0076] The specific compounding process of each layer is as follows: the liquid-triggered transparency-changing film, polyurethane foam, and silicone film are stacked in sequence, and then placed in a hot press, and a pressure of 3000Pa is applied to the edges of the film within a width of 10mm at a temperature of 140°C to soften and bond them, thereby obtaining a wound dressing with the function of visualizing the saturation of the liquid in the body; wherein, during compounding, the granular layer of the liquid-triggered transparency-changing film is in close contact with one side of the polyurethane foam.

[0077] Example 4

[0078] A method for preparing a liquid-triggered transparency-changing film, comprising the following steps:

[0079] (1) mixing a branched polyethyleneimine colloid solution (concentration of 35 mg / ml, solvent of deionized water, manufacturer of branched polyethyleneimine colloid is Beijing Huawei Ruike Chemical Technology Co., Ltd., brand HWG62344) with an anionic polyurethane solution (concentration of 35 wt %, solvent of deionized water, anionic polyurethane is the anionic polyurethane prepared above), and dispersing the mixture at a speed of 7000 rpm for 12 min using a homogenizer to obtain a nanomicelle dispersion; wherein the content of branched polyethyleneimine colloid in the nanomicelle dispersion is 2 wt %, and the content of anionic polyurethane is 35 wt %;

[0080] (2) The nanomicelle dispersion obtained in step (1) was evenly sprayed on a transparent polyurethane film with a thickness of 1.2 mm (manufacturer: Guangzhou Hongxin New Material Technology Co., Ltd., brand: HXE585) using an air brush spray device, and dried at 22° C. for 60 min to obtain a liquid-triggered transparency change film; wherein the spraying pressure was 1.2 Bar, the spraying distance was 10 cm, the spraying time was 15 s, and the spraying amount of the nanomicelle dispersion was 30 μL.

[0081] The thickness of the particle layer sprayed on the transparent polyurethane film in the liquid-triggered transparency change film finally prepared was 35 μm.

[0082] A wound dressing with a function of visualizing the body liquid saturation, comprising an indicator layer, a liquid absorption layer and a contact layer;

[0083] The indicating layer is the liquid-triggered transparency-changing film prepared above, with a thickness of 1.235 mm;

[0084] The liquid-absorbing layer is polyurethane foam with a thickness of 9 mm;

[0085] The contact layer is a polysilicone film with multiple liquid permeable holes (manufacturer: Huizhou Huayang Medical Device Co., Ltd., brand: Soft silicone patch), thickness 0.9mm;

[0086] The wound dressing with the function of visualizing the body liquid saturation is in a non-transparent state when not in contact with exudate, with a transmittance of 48%; it becomes transparent when exudate invades, with a transmittance of 83.01%.

[0087] The specific compounding process of each layer is as follows: polyurethane adhesive (manufacturer is Minnesota Mining Manufacturing Company, brand 4000UV) is evenly coated on each surface where the liquid-triggered transparency change film, polyurethane foam, and silicone film are bonded within a range of 10 mm on all sides of the edge, and after stacking, a pressure of 1000 Pa is applied to fix it, and after the adhesive is cured, a wound dressing with the function of visualizing the saturation of the main body liquid is obtained; wherein, during compounding, the granular layer of the liquid-triggered transparency change film is in close contact with one side of the polyurethane foam.

[0088] Example 5

[0089] A method for preparing a liquid-triggered transparency-changing film, comprising the following steps:

[0090] (1) mixing a branched polyethyleneimine colloid solution (concentration of 40 mg / ml, solvent of deionized water, manufacturer of branched polyethyleneimine colloid is Beijing Huawei Ruike Chemical Technology Co., Ltd., brand HWG62344) with an anionic polyurethane solution (concentration of 45 wt%, solvent of deionized water, anionic polyurethane is the anionic polyurethane prepared above), and then dispersing the mixture at a speed of 9000 rpm for 15 min using a homogenizer to obtain a nanomicelle dispersion; wherein the content of the branched polyethyleneimine colloid in the nanomicelle dispersion is 2.5 wt%, and the content of the anionic polyurethane is 45 wt%;

[0091] (2) The nanomicelle dispersion obtained in step (1) was evenly sprayed on a transparent polyurethane film with a thickness of 1.5 mm (manufacturer: Guangzhou Hongxin New Material Technology Co., Ltd., brand: HXE585) using an air brush spray device, and dried at 22° C. for 90 min to obtain a liquid-triggered transparency change film; wherein the spraying pressure was 2 Bar, the spraying distance was 20 cm, the spraying time was 18 s, and the spraying amount of the nanomicelle dispersion was 40 μL.

[0092] The thickness of the particle layer sprayed on the transparent polyurethane film in the liquid-triggered transparency change film finally prepared is 50 μm.

[0093] A wound dressing with a function of visualizing the body liquid saturation, comprising an indicator layer, a liquid absorption layer and a contact layer;

[0094] The indicator layer is the liquid-triggered transparency change film prepared above, with a thickness of 1.55 mm;

[0095] The liquid-absorbing layer is polyurethane foam with a thickness of 10 mm;

[0096] The contact layer is a polysilicone film with multiple liquid permeable holes (manufacturer: Huizhou Huayang Medical Device Co., Ltd., brand: Soft silicone patch), 1mm thick;

[0097] The wound dressing with the function of visualizing the body liquid saturation is in a non-transparent state when not in contact with exudate, with a transmittance of 45%; it becomes transparent when exudate invades, with a transmittance of 82.21%.

[0098] The specific compounding process of each layer is as follows: polyurethane adhesive (manufacturer is Bezos Polymer New Materials Co., Ltd., brand number 11780) is evenly coated on each surface where the liquid-triggered transparency change film, polyurethane foam, and silicone film are bonded within a range of 5 mm in width on all sides of the edge, and after stacking, a pressure of 500 Pa is applied to fix it, and after the adhesive is cured, a wound dressing with the function of visualizing the saturation of the bulk liquid is obtained; wherein, during compounding, the granular layer of the liquid-triggered transparency change film is tightly attached to one side of the polyurethane foam.

Claims

1. A method for preparing a liquid-triggered transparency-changing film, characterized in that: After the branched polyethyleneimine colloid solution and the anionic polyurethane solution are uniformly mixed to obtain a nano-micelle dispersion, the nano-micelle dispersion is uniformly sprayed on a transparent polyurethane film to prepare a liquid-triggered transparency change film.

2. The method for preparing a liquid-triggered transparency-changing film according to claim 1, characterized in that: The content of branched polyethyleneimine colloid in the nano-micelle dispersion is 5-25wt%, and the content of anionic polyurethane is 15-45wt%.

3. The method for preparing a liquid-triggered transparency-changing film according to claim 1, characterized in that: The thickness of the transparent polyurethane film is 0.5-1.5 mm, and the thickness of the particle layer sprayed on the transparent polyurethane film is 10-50 μm.

4. The method for preparing a liquid-triggered transparency-changing film according to claim 3, characterized in that: The nano-micelle dispersion is sprayed using an air brush spray device.

5. The method for preparing a liquid-triggered transparency-changing film according to claim 4, characterized in that: The spraying pressure is 0.5 to 3 Bar, the spraying distance is 5 to 25 cm, the spraying time is 5 to 20 s, and the spraying amount of the nano-micelle dispersion is 10 to 50 μL.

6. The method for preparing a liquid-triggered transparency-changing film according to claim 5, characterized in that: The nano-micelle dispersion is uniformly sprayed on the transparent polyurethane film and then dried at room temperature for 30 to 120 minutes.

7. A wound dressing with a function of visualizing the body liquid saturation, characterized in that: It is obtained by compounding the indicating layer, the liquid absorbing layer and the contact layer in sequence; The indicating layer is a liquid-triggered transparency-changing film prepared by the method described in any one of claims 1 to 6; the liquid-absorbing layer is polyurethane foam; and the contact layer is a silicone film with a plurality of liquid-permeable holes.

8. The wound dressing with body liquid saturation visualization function according to claim 7, characterized in that: The indicating layer, the liquid absorbing layer and the contact layer are laminated by edge hot pressing or bonding with a polyurethane adhesive.

9. The wound dressing with body liquid saturation visualization function according to claim 8, characterized in that: The thickness of the indicating layer is 0.51-1.55 mm, the thickness of the liquid absorbing layer is 5-10 mm, and the thickness of the contact layer is 0.5-1 mm.

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