A medical dressing

Abstract

The present invention provides a medical dressing, comprising a body, the body at least including a first region, the first region including a thermoplastic copolyester elastomer substrate and a polymer layer; the polymer layer contains at least one polar group functional group of -OH, -SH, -COOH, -OR, -COOR, -PO3H2, -SO3H or -NH2. The medical dressing of the present invention can block gases and germs and has excellent moisture permeability function to keep the humidity environment inside the wound surface consistent with the external environment, so as to maintain a good humidity environment inside the wound surface; the use environment of the medical dressing of the present invention includes not only small wounds after infusion and injection; but also large wounds caused by various injuries such as surgical operations, suture operations, burns, and scalds.

Description

Technical Field

[0001] The present invention belongs to the field of medical care, and particularly relates to a medical dressing. Background Art

[0002] Dressings are common medical protective materials, often used for covering and protecting wounds. For example, after the end of an infusion treatment, the needle is left on the patient's skin without removal, and a dressing is pasted and covered thereon. The space formed between the dressing and the skin accommodates the needle and the wound; another example is in large wounds, for protecting the closed or unclosed wounds; the space formed between the dressing and the skin accommodates sutures or suture instruments. Dressings are used to isolate external germs and dust from entering the space and contaminating the wound. Clinically, especially for wounds with needles or suture instruments left in place, the requirements for dressings include: light transmission, air permeability, and transparency.

[0003] The reasons for wound infections in clinical practice are: the accumulation of wound exudate and the air permeability of the wound; the long-term accumulation of exudate will cause secondary damage to the wound, and poor air permeability of the wound will exacerbate this situation. The traditional method of nursing a wound mainly uses gauze covering to absorb the exudate of the wound, but this method is prone to cause secondary damage when replaced again, and has been gradually replaced in clinical practice; this has led to the rapid development of the field of medical dressings. In the prior art, while the dressing meets the requirements of isolating the outside air and contamination, it also isolates the exchange of water vapor inside and outside the dressing. When blood oozes from the wound or fluid accumulates and oozes from the needle, the moisture inside the dressing cannot be discharged in time, resulting in wound infection; the above problems are solved by replacing special moisture-absorbing materials. The new moisture-absorbing materials can quickly absorb the exudate of the wound and avoid adhesion to the wound, but this technology has requirements for the amount of material used, and the moisture-absorbing material is in direct contact with the wound surface, making it difficult to ensure clinical safety, and most materials themselves are not light-transmitting, making it difficult to meet the nursing requirements of large wounds that need to be continuously observed. Based on this, the present invention is proposed: Summary of the Invention

[0004] The object of the present invention is to overcome the deficiencies of the prior art and provide a medical dressing that can block gases and germs while allowing moisture to pass through; keeping the humidity environment inside the wound consistent with the external environment, thereby maintaining a good humidity environment inside the wound.

[0005] The object of the present invention is achieved by the following technical solutions. A medical dressing includes a body 1, and the body at least includes a first region 11. The first region 11 includes a thermoplastic copolyester elastomer substrate 111 and a polymer layer 112. The polymer layer contains at least one polar group functional group among -OH, -SH, -COOH, -OR, -COOR, -PO3H2, -SO3H or -NH2. The preparation method of the first region includes the following steps: S1. Dispersing the polymer into a solvent to form a polymer solution, and the solvent is water or a polar solvent; S2. Coating the polymer solution onto the surface of the thermoplastic copolyester elastomer substrate to form a first wet film 311, wherein the polymer contains at least one polar group functional group among -OH, -SH, -COOH, -OR, -COOR, -PO3H2, -SO3H or -NH2; so as to be suitable for water molecules to permeate from the side with a high concentration to the side with a low concentration, while gas is blocked.

[0006] In the present invention, at least a part of the body is set as a composite of a thermoplastic copolyester elastomer substrate 111 and a polymer layer 112. On the basis of satisfying the physical barrier between the inside and outside of the wound surface, the water molecules inside the wound surface can penetrate through the first region and exude to the external environment, thereby reducing the environmental humidity inside the wound surface and making the humidity inside the wound surface consistent with the external environment.

[0007] In the first region of the medical dressing of the present invention, the polar group functional groups of the polymer layer build an enhanced "water permeable and moisture conductive channel of hydrophilic-hydrophobic groups", ensuring that while isolating air and pollution on both sides of the first region, water molecules or other polar molecules can be selectively allowed to pass freely; the thermoplastic copolyester elastomer substrate realizes the gas barrier function, and the polar group functional groups in the polymer layer are crosslinked with the molecules in the thermoplastic copolyester elastomer substrate, and the two have better fusion performance, further improving the moisture permeability effect of the polar group functional groups. When the environmental humidity inside the wound surface is too high, the water molecules inside the wound surface can pass through the polymer layer and the thermoplastic copolyester elastomer substrate, thereby reducing the environmental humidity inside the wound surface and making it consistent with the external environment, which is beneficial to wound healing.

[0008] Furthermore, the medical dressing of the present invention further includes a second region, which has adhesiveness at the second region to fix the medical dressing to the skin near the wound surface.

[0009] Furthermore, the copolyester elastomer substrate of the present invention can be prepared into a soft or hard form to adapt to different wound surface conditions; when the wound surface is large and the gap between the wound surface and the dressing needs to be large to accommodate suture instruments or other instruments, the substrate has a higher hardness to have a certain supporting property. When the wound surface is small and the gap between the wound surface and the dressing needs to be small, only a needle needs to be accommodated or only the wound surface needs to be covered, the substrate can be prepared into a soft form.

[0010] Furthermore, the polymer of the present invention is selected from natural, semi-synthetic or synthetic materials.

[0011] Furthermore, the polymer layer of the present invention further includes one or more of antibacterial materials, bactericidal materials, and wound repair materials; to meet different application requirements.

[0012] Furthermore, the first region of the main body of the present invention may further include an absorption layer to absorb wound exudate in a timely manner

[0013] Furthermore, in S1 of the preparation method of the first region of the medical dressing of the present invention, the polar solvent is selected from one or more of ethanol, n-propanol, isopropanol, butanol, ethyl acetate, tetrahydrofuran, and acetonitrile;

[0014] Furthermore, in S1 of the preparation method of the first region of the medical dressing of the present invention, a performance aid is added to the polymer solution, and the functional aid is selected from one or more combinations of antibacterial materials, bactericidal materials, or wound repair materials.

[0015] Furthermore, in S1 of the preparation method of the first region of the medical dressing of the present invention, a functional aid is added to the polymer solution, including any one or more combinations of thickeners, penetrants, crosslinking agents, and hardeners. Description of the Drawings

[0016] Figure 1 - Schematic structural diagram of the first region of the medical dressing of the present invention

[0017] Figure 2 - Schematic overall structural diagram of Example II of the medical dressing of the present invention

[0018] Figure 3 - Schematic overall structural diagram of Example II of the medical dressing of the present invention

[0019] Figure 4 - Schematic overall structural diagram of Example III of the medical dressing of the present invention

[0020] Figure 5 - Schematic overall structural diagram of Example IV of the medical dressing of the present invention Detailed Embodiments

[0021] The principles and spirit of the present invention will be described below with reference to several exemplary embodiments. It should be understood that these embodiments are given only to enable those skilled in the art to better understand and then implement the present invention, and do not limit the scope of the present invention in any way.

[0022] The first area of the medical dressing of the embodiment of the present invention covers the wound surface, thereby forming a seal between the wound surface and the external environment. In the prior art, the moisture permeability of the corresponding material of the first area is poor, which makes the humidity of the wound surface environment high. Long-term high humidity is not conducive to wound healing, and it also reduces the adhesive performance of the medical dressing. The adhesive area is partially infiltrated by moisture, resulting in weak adhesion and even dressing detachment.

[0023] The use environment of the medical dressing described in the present invention includes not only small wounds after infusion and injection, but also large wounds caused by various injuries such as surgical operations, suture operations, burns, scalds, etc.

[0024] The medical dressing of an embodiment of the present invention includes a main body 1, which includes at least a first region 11. The first region 11 includes a thermoplastic copolyester elastomer substrate 111 and a polymer layer 112; the polymer layer contains at least one polar functional group selected from -OH, -SH, -COOH, -OR, -COOR, -PO3H2, -SO3H or -NH2.

[0025] On the basis of satisfying the gas and physical barriers between the inside and outside of the wound, the water molecules in the wound can penetrate the first area and seep into the external environment, thereby reducing the environmental humidity in the wound, so that the humidity in the wound is consistent with the external environment; the polar functional group builds a reinforced "hydrophilic-hydrophobic group water-permeable moisture-conducting channel" to ensure that the air and pollution are isolated between the two sides of the first area, and water molecules or other polar molecules can be selectively passed freely; the thermoplastic copolyester elastomer substrate realizes the gas barrier function, and the polar functional groups in the polymer layer are cross-linked with the molecules in the thermoplastic copolyester elastomer substrate, and the fusion performance of the two is better, which further improves the moisture permeability effect of the polar functional groups. At the same time, the thermoplastic copolyester elastomer substrate 111 and the polymer layer 112 have high composite light transmittance, which is conducive to wound observation. There is no need for medical staff to frequently open the wound to observe the wound in clinical use, causing pollution.

[0026] Those skilled in the art will understand that Figure 1 As shown, the body 1 only includes the first region. In this case, the body 1 is entirely composed of the first region, including the thermoplastic copolyester elastomer substrate 111 and the polymer layer 112. The medical dressing is flexible as a whole and can cover a small wound surface or cover a small irregular wound surface after free cutting. The medical dressing can be fixed with the help of traditional medical tape or other medical adhesives or fixing supplies, and can be used flexibly in clinical practice.

[0027] like Figure 2 or Figure 3As shown in the figure, the body 1 includes a first region 11 and a second region 12. The second region 12 has adhesiveness to fix the medical dressing to the skin near the wound surface. The overall medical dressing is flexible and can cover a small wound surface. The medical dressing can be processed into a rectangle, square, circle, triangle, special shape, etc.

[0028] As Figure 4 shown in the figure, the body 1 includes a first region. In this case, the body 1 is entirely composed of the first region, including a thermoplastic copolyester elastomer substrate 111 and a polymer layer 112. The overall hardness of the medical dressing is increased, and it has a certain degree of support, and can cover a large wound surface; the fixation of the medical dressing can be achieved by means of traditional medical tapes or other medical adhesive products or fixing products, which can be flexibly used in clinical practice. The medical dressing can be processed into a rectangle, square, circle, triangle, special shape, etc.; at the same time, it can have a certain height to better accommodate other auxiliary medical instruments; to be applicable to different situations in clinical practice;

[0029] As Figure 5 shown in the figure, the body 1 includes a first region 11 and a second region 12. The second region 12 has adhesiveness. The overall hardness of the medical dressing is increased, and it has a certain degree of support, and can cover a large wound surface; the medical dressing is fixed to the skin near the wound surface through the second region 12; the medical dressing can be processed into a rectangle, square, circle, triangle, special shape, etc.; at the same time, it can have a certain height to better accommodate other auxiliary medical instruments; to be applicable to different situations in clinical practice.

[0030] The preparation method of the first region of the present invention includes the following steps: S1. Dispersing the polymer into a solvent to form a polymer solution, and the solvent is water or a polar solvent; S2. Coating the polymer solution on the surface of the thermoplastic copolyester elastomer substrate to form a first wet film 311. Among them, the polymer contains at least one polar group functional group such as -OH, -SH, -COOH, -OR, -COOR, -PO3H2, -SO3H or -NH2; so as to be suitable for the water molecules to permeate from the side with a high concentration to the side with a low concentration, while the gas is blocked. Thereby ensuring that the humidity of the wound surface environment is consistent with the external environment, and also ensuring the adhesiveness of the medical dressing.

[0031] The polymer composite film prepared by the present invention can selectively permeate water molecules, and can block other substances such as gases, and also has good biocompatibility, and has broad application prospects.

[0032] In the embodiment of the present invention, various selected polymers can be dissolved separately to form solutions, and then mixed evenly to obtain a polymer solution.

[0033] The high molecular polymer described in the present invention is selected from natural, semi-synthetic or synthetic materials such as lignin salts (lignin salts are generally lignosulfonates, such as sodium lignosulfonate); cellulose polymers such as methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose and their sodium and potassium salts, nanofibrillated cellulose (CNFs), lignin-containing cellulosic nanofibrils (LCNFs), guar gum, gum arabic, gelatin, pectin, xanthan gum, collagen, soy protein isolate, silk protein, protamine, fibroin, polysaccharides such as chitosan, dextran, mannan, succinoglucan, soy polysaccharide and their derivatives, alginate, agar powder, polyacrylic acid, long-chain alkyl (carbon atom number: 10 - 30) acrylate ether, ethylene / acrylic acid (EAA) copolymer, ethylene / vinyl alcohol (EVOH) copolymer, and polyvinyl alcohol (PVA), etc. These resins are water-soluble or can be chemically produced from natural resources. Among them, suitable cellulose can include hemicellulose, such as xylan, microfibrillated cellulose, microcrystalline cellulose and nanofibrillated cellulose, starch and its derivatives, cellulose polymers such as methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose and their sodium and potassium salts, nanofibrillated cellulose (CNFs), lignin-containing cellulosic nanofibrils (LCNFs), guar gum, gum arabic, gelatin, pectin, xanthan gum, casein, albumin, collagen, soy protein isolate, silk protein, protamine, fibroin, polysaccharides such as chitosan, dextran, mannan, succinoglucan, soy polysaccharide and their derivatives, alginate, agar powder, polyacrylic acid, long-chain alkyl (carbon atom number: 10 - 30) acrylate ether, ethylene / acrylic acid copolymer, ethylene / vinyl alcohol copolymer, and at least two of polyvinyl alcohol resins, which can be combined to form a film layer that selectively permeates water molecules while blocking other substances such as gases, that is, the film layer is airtight and has a "dynamic" moisture permeability effect.

[0034] Specifically, the many polar group functional groups contained in the synthetic polymer or biopolymer selected in the present invention are: -OH, -SH, -COOH, -OR, -COOR, -PO3H2, -SO3H, and -NH2, etc. Then, these polar group functional groups and various functional additives are organically integrated and formulated to build a "water-permeable and moisture-conducting channel with enhanced hydrophilic-hydrophobic groups". This construction mode is different from the generally understood method of using bricks to fix the tunnel wall for covering a tunnel. The membrane material described in this application will be affected by the surrounding temperature and humidity during use, and its internal structure will change through the effective chemical bond linkages of hydrogen bonds, ionic bonds, and / or non-dynamic covalent bonds and dynamic covalent bonds.

[0035] For example, as the humidity and temperature increase, the efficiency of water molecules passing through the membrane material increases, indicating that the enhanced water-permeable channel composed of polar hydrophilic groups and non-polar hydrophobic groups is closely related to temperature and humidity. Especially when the environmental temperature is high, more water-permeable channels are dynamically formed to transport water molecules to the other side of the membrane.

[0036] In some examples, in the humidity range of 20% - 60% and without external pressure, if the temperature is low, such as 20°C, the passing rate level of water molecules passing through the membrane material autonomously is basically stable because at this temperature, the chemical bond linkages are relatively stable, and the formed water-permeable channels are less affected by the high or low humidity of the water molecule output side environment; while at medium temperatures, such as 25°C or higher temperatures, the chemical bond linkages are likely to change, and the water-permeable channels change accordingly. Therefore, when water molecules move towards the side of the membrane with relatively lower humidity, the passing speed will be higher, and when moving towards the side of the membrane with relatively higher humidity, the passing speed will be lower.

[0037] The molecular weight of the selected polymer in the present invention is between 5000 and 5000000; at least two of them are selected and formulated in a certain proportion, with excellent performance in blocking most substances but allowing water vapor to pass through. And, the mass percentage of the polymer in the polymer solution can be 2% - 25%, preferably 5% - 25%, for example, 10%, 12%, 15%, 16%, 18%, 20%, 21%, 24%.

[0038] The embodiments of the present invention can be carried out under a constant temperature condition selected from the range of 10 - 100°C. The selected polymer is dissolved in an aqueous medium to form a solution at a predetermined time and sequence, and fully stirred to dissolve and mix evenly. Among them, the solvent used can be pure water, or it can also be a polar solvent, selected from one, two, or more mixtures of ethanol, n-propanol, isopropanol, butanol, ethyl acetate, tetrahydrofuran, and acetonitrile.

[0039] In the preparation method of the present invention, S2 is coated on the surface of a thermoplastic copolyester elastomer substrate to form a first wet film, which is dried to obtain a composite film material with "dynamic" moisture permeability and airtightness. Among them, the thickness of the wet film is generally 10-300 microns. The form of drying can be air-drying at room temperature or other forms such as baking, and the temperature can be 20-120°C, so that the thickness of the dried wet film is 1-100 microns.

[0040] In the examples of the present invention, under the condition of a temperature range of 10-200°C, the above-prepared polymer or composite solution is applied to a thermoplastic copolyester elastomer substrate through one or more processes such as casting, calendering, molding, extrusion, unidirectional stretching, biaxial stretching, and various optional coating processes, thereby obtaining a composite film material.

[0041] According to different functional requirements, the examples of the present invention optionally add functional materials, such as antibacterial materials, bactericidal materials, and wound repair materials, to the solution obtained in step S1, and stir well to mix evenly to obtain a composite solution.

[0042] The antibacterial or bactericidal materials of the present invention can be selected from: inorganic materials, including but not limited to: inorganic antibacterial materials such as Ag, Zn, Cu, and Ti systems; photocatalytic materials, including but not limited to: N-type semiconductor metal oxides such as TiO2, ZnO, CdS, WO3, SnO2, and Fe2O3, preferably TiO2, which has higher oxidation activity, stronger stability, and relatively small toxic and side effects on the human body; nanomaterials, including but not limited to, including nano-treated inorganic antibacterial materials; organic material synthesis types, including but not limited to: imidazoles, pyridines, isothiazolinones, phenols, quaternary ammonium salts, phenols, acyl anilines, biguanides, vanillin or ethyl vanillin compounds, and organic antibacterial materials such as synthetic antibiotics; natural materials, including but not limited to: extracts of Cortex Moutan, Chinese prickly ash, chili peppers, garlic, mountain yucca, Moso bamboo, mint, lemon leaves, etc., chitosan and its derivatives, polypeptide compounds, etc. extracted from crabs and shrimps; polymer materials, including but not limited to: polystyrene caprolactam, poly pyrazole, polyhexamethylene hydrochloride guanidine, polyvalent salt polymer antibacterial agents, etc.; composite antibacterial materials, including but not limited to: composites of two or more of organic antibacterial fungicides, inorganic antibacterial fungicides, natural antibacterial fungicides, and polymer antibacterial fungicides.

[0043] The repair materials of the present invention can be selected from including but not limited to: fibroblast growth factor, epidermal growth factor; allogeneic skin, xenogeneic skin, amniotic membrane, and tissue derivatives such as: collagen, etc.; silk fibroin; traditional Chinese medicine; plant extracts, plant extract derivatives; proteins; polypeptides; polymer materials; chitosan; alginate; hyaluronic acid and its derivatives, etc.

[0044] To further understand the present application, the following specifically describes the polymer composite film provided by the present application and its preparation method in conjunction with embodiments.

[0045] The performance test of the film material of the present invention is carried out with reference to the method requirements of GB / T458, YY / T 0148-2006 "General Requirements for Medical Adhesive Bandages, Medical adhesive bandages-Gerenal requirements" and YY / T 0471-2004 "Test Methods for Primary Wound Dressings, Test Methods for primary wound dressings".

[0046] Example 1

[0047] Preparation method for the first area of the medical dressing:

[0048] 1. Prepare a 10% silk fibroin aqueous solution with purified water or ordinary water and stir evenly.

[0049] 2. Prepare a 2% sodium alginate aqueous solution with purified water or ordinary water and stir thoroughly until completely dissolved.

[0050] 3. Prepare a 10% gelatin aqueous solution with purified water or ordinary water and stir to dissolve. Appropriate heating can be used to assist dissolution according to the dissolution situation.

[0051] 4. Prepare a 3% carboxymethyl cellulose aqueous solution with purified water or ordinary water and stir evenly.

[0052] 5. Slowly and evenly mix the solutions prepared in steps 1, 2, 3, and 4 in the same number of parts by weight in sequence.

[0053] 6. According to the solid content of the above mixed solution, respectively add a small amount of 45% benzalkonium chloride aqueous solution, tannic acid, nano-titanium dioxide, and silane coupling agent A-171 (the dosage of each is about 0.3-1% of the solid content of the solution), and then stir at 50°C for 3 hours.

[0054] 7. Apply the solution obtained in step 6 on the surface of a transparent thermoplastic copolyester elastomer substrate (with a thickness of about 15 microns) to form a polymer wet film, and dry it at room temperature to obtain a polymer composite film.

[0055] Among them, the scraping thickness of the polymer wet film is 15 microns, and the thickness of the film layer after drying at room temperature is about 2-3 microns.

[0056] Example 2

[0057] Preparation method for the first area of the medical dressing:

[0058] 1 Prepare 5% chitosan aqueous solution with purified water or ordinary water and stir to dissolve evenly.

[0059] 2 Prepare a 5% nisin aqueous solution with purified water or ordinary water and stir evenly.

[0060] 3 Prepare a 10% acrylic acid aqueous solution with purified water or ordinary water and stir to dissolve.

[0061] 4. Prepare a 3% carboxymethyl cellulose aqueous solution with purified water or ordinary water and stir thoroughly.

[0062] 5 Slowly mix the solutions prepared in steps 1, 2, 3, and 5 in the same weight ratio in sequence.

[0063] 6. According to the solid content of the mixed solution, add a small amount of natamycin, nano titanium dioxide and silane coupling agent A-171 (each amount is about 0.5-1% of the solid content of the solution), and then stir at 50°C for 3 hours.

[0064] 7. Apply the solution obtained in step 6 to a 30-micron transparent thermoplastic copolyester elastomer substrate and dry it at room temperature to obtain a high molecular polymer composite film.

[0065] The coating thickness of the high molecular polymer wet film is 15 microns, and the film thickness after drying at room temperature is about 2-3 microns.

[0066] The second region preparation method comprises coating the corresponding second region with a medical-grade water-based acrylic pressure-sensitive adhesive, wherein the pressure-sensitive adhesive has a wet film thickness of 40 microns and is dried at room temperature to form a self-adhesive composite film.

[0067] Example 3

[0068] Preparation method of the first area of medical dressing:

[0069] 1 Prepare 2% sodium alginate aqueous solution with purified water or ordinary water, and stir thoroughly until it is completely dissolved.

[0070] 2 Prepare a 5% chitosan aqueous solution with purified water or ordinary water and stir to dissolve evenly.

[0071] 3. Prepare a 10% silk protein aqueous solution with purified water or ordinary water and stir evenly.

[0072] 4 Prepare a 10% acrylic acid aqueous solution with purified water or ordinary water and stir to dissolve.

[0073] 5. Prepare a 3% carboxymethyl cellulose aqueous solution with purified water or ordinary water and stir thoroughly.

[0074] 6. Slowly mix the solutions prepared in steps 1, 2, 3, 4 and 5 in the same weight ratio in order.

[0075] 7 According to the solid content of the above mixed solution, a small amount of polylysine, lysozyme, nano-titanium dioxide and silane coupling agent A-171 are respectively added (the dosage of each is about 0.5-1% of the solid content of the solution), and then stirred at 50 °C for 3 hours.

[0076] 8 The solution obtained in step 7 is applied to a 10-micron transparent thermoplastic copolyester elastomer substrate and dried at room temperature to obtain a polymer composite film.

[0077] Among them, the scraping thickness of the polymer wet film is 15 microns, and the film thickness after drying at room temperature is about 2-3 microns.

[0078] Example 4

[0079] Preparation method of the first region of the medical dressing:

[0080] 1 Prepare a 10% gelatin aqueous solution with pure water or ordinary water, and stir and dissolve. Appropriate heating can be carried out according to the dissolution situation to assist dissolution.

[0081] 2 Prepare a 5% chitosan aqueous solution with pure water or ordinary water, and stir and dissolve evenly.

[0082] 3 Prepare a 5% protamine aqueous solution with pure water or ordinary water, and stir evenly.

[0083] 4 Prepare a 2% sodium alginate aqueous solution with pure water or ordinary water, and stir fully until completely dissolved.

[0084] 5 Prepare a 3% carboxymethyl cellulose aqueous solution with pure water or ordinary water, and stir fully until evenly mixed.

[0085] 6 Slowly mix the solutions prepared in steps 1, 2, 3, 4 and 5 in the same number of parts by weight in sequence and mix evenly.

[0086] 7 According to the solid content of the above mixed solution, a small amount of lysozyme, sodium hyaluronate, 45% benzalkonium chloride aqueous solution (the dosage of each is about 0.5-1% of the solid content of the solution) are respectively added, and then stirred at 50 °C for 3 hours.

[0087] 8 The solution obtained in step 7 is applied to an 8-micron thermoplastic copolyester elastomer substrate and dried at room temperature to obtain a polymer composite film.

[0088] Among them, the scraping thickness of the polymer wet film is 15 microns, and the film thickness after drying at room temperature is about 2-3 microns.

[0089] Method for preparing the second region: Coat a medical-grade aqueous acrylic pressure-sensitive adhesive on the corresponding second region. The wet film thickness of the pressure-sensitive adhesive is 40 microns, and it is air-dried at room temperature to form a self-adhesive composite film.

[0090] Example 5

[0091] Method for preparing the first region of the medical dressing:

[0092] 1. Prepare a 10% aqueous silk protein solution with purified water or ordinary water and stir evenly.

[0093] 2. Prepare a 2% aqueous sodium alginate solution with purified water or ordinary water and stir well until completely dissolved.

[0094] 3. Prepare a 10% aqueous gelatin solution with purified water or ordinary water and stir to dissolve. If necessary, heat appropriately to assist dissolution according to the dissolution situation.

[0095] 4. Prepare a 3% aqueous carboxymethyl cellulose solution with purified water or ordinary water and stir evenly.

[0096] 5. Slowly mix the solutions prepared in steps 1, 2, 3, and 4 in equal parts by weight in sequence and mix evenly.

[0097] 6. According to the solid content of the above mixed solution, add a small amount of 45% aqueous benzalkonium chloride solution, tannic acid, nano-titanium dioxide, and silane coupling agent A-171 (the dosage of each is about 0.3-1% of the solid content of the solution), and then stir at 50 °C for 3 hours.

[0098] 7. Apply the solution obtained in step 6 on the surface of a PE film (thickness about 20 microns) to form a polymer wet film, and air-dry at room temperature to obtain a polymer composite film.

[0099] Among them, the scraping thickness of the polymer wet film is 15 microns, and the thickness of the film layer after drying at room temperature is about 2-3 microns.

[0100] Example 6

[0101] Method for preparing the first region of the medical dressing:

[0102] 1. Prepare a 10% aqueous silk protein solution with purified water or ordinary water and stir evenly.

[0103] 2. Prepare a 2% aqueous sodium alginate solution with purified water or ordinary water and stir well until completely dissolved.

[0104] 3. Prepare a 10% aqueous gelatin solution with purified water or ordinary water and stir to dissolve. If necessary, heat appropriately to assist dissolution according to the dissolution situation.

[0105] 4. Prepare a 3% aqueous carboxymethyl cellulose solution with purified water or ordinary water and stir evenly.

[0106] 5 Mix the solutions prepared in Steps 1, 2, 3, and 4 in the same number of parts by weight in sequence and mix them evenly slowly.

[0107] 6 According to the solid content of the above mixed solution, add a small amount of 45% benzalkonium chloride aqueous solution, tannic acid, nano-titanium dioxide, and silane coupling agent A-171 (the dosage of each is about 0.3-1% of the solid content of the solution), and then stir at 50 °C for 3 hours.

[0108] 7 Apply the solution obtained in Step 6 onto the surface of the diaper breathable film (with a thickness of about 40 microns) to form a polymer wet film, and dry it at room temperature to obtain a polymer composite film.

[0109] Among them, the scraping thickness of the polymer wet film is 15 microns, and the thickness of the film layer after drying at room temperature is about 2-3 microns.

[0110] To better illustrate the effects of the present invention, the following test methods and detection means adopted by the present invention are given, and the test results of each example are listed and shown.

[0111] 1. Air permeability test:

[0112] Test method: Using the differential pressure method,

[0113] Detection means: Under the condition of meeting the GB / T458 standard, use the FBS-TQ110 high-precision computer air permeability tester to test the air permeability of the film sample. The unit of air permeability is um / (Pa·s) @ differential pressure 1 kPa

[0114] 2. Water resistance test:

[0115] Test method: YY / T0471.3-2004 Experimental methods for contact wound dressings - Part 3: Water resistance.

[0116] Detection means: Conduct inspection according to the water resistance test method specified in the YY / T0471.3-2004 standard. The experimental result should meet the requirement of Article 2.2: the ability to withstand a static water pressure of 500 mm for 300 seconds.

[0117] 3. Water vapor transmission rate test:

[0118] Test method: The water vapor transmission rate test method specified in the YY / T0471.2-2004 standard.

[0119] Detection means: Conduct inspection according to the water vapor transmission rate test method specified in the YY / T0471.2-2004 standard. The experimental result should be greater than or equal to 1000 g / square meter / 24 hours.

[0120] 4. Bacteria resistance test:

[0121] Test method: YY / T 0471.5-2004 Experimental methods for contact wound dressings - Part 5: Bacteria barrier property

[0122] Detection means: Test according to the bacterial species specified in the standard in Part 5 of YY / T 0471.5-2004 Experimental methods for contact wound dressings

[0123] The test results of the air permeability, water resistance, water vapor transmission rate and bacteria barrier property of the membrane materials in the example group are as follows in the table:

[0124]

[0125] As can be seen from the above examples, the present invention selects at least two specific high molecular polymers, which are processed by different coating processes such as roll coating, spraying or printing, to form a film layer with barrier properties but selectively permeable to water molecules, thereby obtaining a high molecular polymer composite film. The high molecular polymer composite film prepared by the present invention can selectively permeate water molecules, that is, has dynamic moisture permeability, and can block other substances such as gases. In addition, due to the use of high molecular polymers derived from nature or having water solubility, the composite membrane material has good biocompatibility, can be biodegradable, and is environmentally friendly. Further, the present invention can use water as a solvent, with less or no use of toxic organic solvents, and has better environmental protection performance.

[0126] It can be clearly seen from the experimental results listed in the table that the membrane materials obtained in each example group all have good gas barrier, water resistance, moisture permeability and antibacterial properties. Especially, the water vapor transmission rate is far higher than the standard requirements. Comparing Example 1, Example 5 and Example 6, except for the different substrates, other conditions are the same; the results show that the properties such as air permeability, water resistance and water vapor transmission rate are basically the same, indicating that the medical dressing of the present invention has similar properties to the PE microporous substrate and the breathable film substrate of diapers in the prior art and can achieve clinical substitution; at the same time, this medical dressing is transparent; due to the micropores in the PE microporous substrate and the microporous film substrate of diapers themselves, the light path changes after passing through, resulting in the substrate being opaque; therefore, the clinical use is not flexible; the medical dressing material used in the present invention is transparent itself, and the clinical application effect is better. Examples 1 to 4 all adopt the transparent thermoplastic copolyester elastomer substrate described in the present invention; the experimental results show that its performance meets the standards.

[0127] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention. The above is only the preferred implementation manner of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and modifications can still be made, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A medical dressing, comprising a main body (1), characterized in that, The body at least includes a first region (11), and at the first region (11), there are a transparent thermoplastic copolyester elastomer substrate (111) and a polymer layer (112); the polymer layer contains at least one polar group functional group among -OH, -SH, -COOH, -OR, -COOR, -PO3H2, -SO3H or -NH2; the polar group functional groups in the polymer layer crosslink with the molecules in the transparent thermoplastic copolyester elastomer substrate; The polymer layer contains at least two water-soluble polymers; The polymer layer is one of the following polymer compositions; (1) 10% aqueous silk fibroin solution, 2% aqueous sodium alginate solution, 10% aqueous gelatin solution, 3% aqueous carboxymethyl cellulose solution, and their weight ratio is 1:1:1:1; (2) 5% aqueous chitosan solution, 5% aqueous nisin solution, 10% aqueous acrylic acid solution, 3% aqueous carboxymethyl cellulose solution, and their weight ratio is 1:1:1:1; (3) 2% aqueous sodium alginate solution, 5% aqueous chitosan solution, 10% aqueous silk fibroin solution, 10% aqueous acrylic acid solution, 3% aqueous carboxymethyl cellulose solution, and their weight ratio is 1:1:1:1:1; (4) 10% aqueous gelatin solution, 5% aqueous chitosan solution, 5% aqueous protamine solution, 2% aqueous sodium alginate solution, 3% aqueous carboxymethyl cellulose solution, and their weight ratio is 1:1:1:1:

1.

2. The medical dressing according to claim 1, wherein The body (1) includes a first region (11) and a second region (12), and the second region (12) has adhesiveness.

3. The medical dressing according to claim 2, wherein The medical dressing as a whole may not have support or may have support to adapt to the preparation of different structures.

4. The medical dressing according to any one of claims 1 to 3, characterized in that, The medical dressing as a whole is processed into a rectangle, a square, a circle, or a triangle to adapt to different wounds.

5. A preparation method of a medical dressing, characterized in that, It includes the following steps: S1. Disperse the polymer into a solvent to make a polymer solution, and the solvent is water or a polar solvent; S2. Coat the polymer solution on the surface of the transparent thermoplastic copolyester elastomer substrate to form a first wet film (311), wherein the polymer contains at least one polar group functional group among -OH, -SH, -COOH, -OR, -COOR, -PO3H2, -SO3H or -NH2; the polar group functional groups in the polymer layer crosslink with the molecules in the transparent thermoplastic copolyester elastomer substrate; The polymer layer contains at least two water-soluble polymers; The polymer layer is one of the following polymer compositions; (1) 10% aqueous silk fibroin solution, 2% aqueous sodium alginate solution, 10% aqueous gelatin solution, 3% aqueous carboxymethyl cellulose solution, and their weight ratio is 1:1:1:1; (2) 5% aqueous chitosan solution, 5% aqueous nisin solution, 10% aqueous acrylic acid solution, 3% aqueous carboxymethyl cellulose solution, and their weight ratio is 1:1:1:1; (3) 2% sodium alginate aqueous solution, 5% chitosan aqueous solution, 10% silk fibroin aqueous solution, 10% acrylic acid aqueous solution, 3% carboxymethyl cellulose aqueous solution, and their weight ratio is 1:1:1:1:1; (4) 10% gelatin aqueous solution, 5% chitosan aqueous solution, 5% protamine aqueous solution, 2% sodium alginate aqueous solution, 3% carboxymethyl cellulose aqueous solution, and their weight ratio is 1:1:1:1:

1.

6. The preparation method of a medical dressing according to claim 5, characterized in that, The polar solvent is selected from one or more of ethanol, n-propanol, isopropanol, butanol, ethyl acetate, tetrahydrofuran, and acetonitrile.

7. The preparation method of a medical dressing according to claim 6, characterized in that, In the step S1, a performance aid is added to the polymer solution, including one or more of an antibacterial agent, a bactericide, and a wound repair aid, to meet different usage requirements of the medical dressing.

8. A method for preparing a medical dressing according to any one of claims 5-7, characterized in that, In the step S1, a functional aid is added to the polymer solution, including one or more combinations of a thickener, a penetrant, a crosslinking agent, and an adhesive.

Images