KR100937816B1 - Manufacturing method of hydrophilic foam dressing material and manufactured hydrophilic foam dressing material - Google Patents

Abstract

The present invention relates to a method for manufacturing a polyurethane foam dressing material that protects wounds such as wounds and burns and helps wound healing, and in particular, a polyurethane of a new process that greatly improves productivity and processing efficiency and improves physical properties of the foam dressing material. A method for producing a foam dressing material. To this end, in the present invention, the manufacturing step of the moisture-permeable waterproof polyurethane film layer; Preparing a polyurethane prepolymer; Preparing a polyurethane foam mixture; Obtaining a polyurethane foam layer in a gel state with a tack property; Method of manufacturing a polyurethane foam dressing material comprising the step of laminating a polyurethane foam layer and a polyurethane film layer in a gel state and winding and maturing the prepared polyurethane foam dressing material in the form of a roll (Roll) There is also provided a new manufacturing method for improving the absorption rate of the foam dressing material through surface modification of impregnating and drying the prepared polyurethane foam in the humectant and treating oxygen plasma. According to the present invention, the productivity and processing efficiency can be greatly improved, so that mass production of foam dressing material is possible, and thus, the production cost is greatly reduced, thereby providing foam dressing material having excellent physical properties at low cost.

Dressings, foams, polyurethanes, wounds, wound dressings, sheets, prepolymers, hydrophilic

Description

A method for manufacturing hydrophilic Wound dressing and the Hydrophilic Wound Dressing}

The present invention relates to a method for manufacturing a polyurethane foam dressing material that protects wounds such as wounds and burns and helps wound healing, and in particular, a polyurethane of a new process that greatly improves productivity and processing efficiency and improves physical properties of the foam dressing material. It relates to a method for producing a foam dressing material and to a polyurethane foam dressing material thus prepared.

The treatment of wounds is the basis of medicine and has a long history. According to Papyrus, animal oil, honey, and cotton have been used to treat wounds since 5000 BC. Throughout history, many changes and advances have been made in the treatment of wounds. Since 1962, a zoologist, published a research paper that suggests that keeping wounds wet helps to heal rather than drying them to crusts, the benefits of wet wound treatment Continually proven and emphasized. Wet dressing methods to prevent dehydration or drying of fluids secreted from wounds have now been found to facilitate wound healing.

The ideal dressing material should maintain a moist environment between the wound and the dressing material, have adequate absorbency and moisture permeability, prevent drying of the wound surface and avoid the swelling of the surrounding normal skin. In addition, it should have functionalities such as gas exchange and prevention of invasion of bacteria from the outside, and should not stick to the wound surface and cause damage to new tissues or the like. In addition, it is an ideal dressing material if the wound healing state can be easily observed, non-irritating, easy to use, and economical. Research efforts to develop a dressing material that satisfies all of these ideal conditions continue.

The dressing materials that have been used relatively recently are as follows. In the early 1970s, “OpSite ™” was introduced as a semi-transparent transparent film that promotes wound healing by keeping the wound moist, promoting dissolution of necrotic tissue and granulation tissue. However, due to the excessive amount of exudates around the wound, the surrounding skin becomes crushed, and the exudates leak out and have to be discharged at random.

In 1982, a product called “DuoDERM ™” was introduced in the United States, a hydrocolloid dressing that, when attached to a wound, reacted with exudate to provide a gel-type moist environment that promotes wound epithelialization. However, the gas and water vapor such as oxygen and carbon dioxide did not pass, so there was a drawback of excessive exudates, there was a problem that the gel may remain on the wound surface during dressing exchange.

Dressing materials using polymers have been mainly produced by the gelation method, but recently, a foam manufacturing method for forming open pores by foaming synthetic polymers such as polyurethane is also used.

U.S. Patent No. 4,664,662 (Aug. 13, 1985), U.S. Patent No. 4,860,737 (August 1, 1983), U.S. Patent No. 5,147,338 (1991.6.17) and the like have a hydrophilic polyurethane prepolymer having two or more isocyanate end groups; Polyurethane foam dressing materials prepared by mixing and foaming drugs such as water, nonionic surfactants, and antibacterial agents such as silver sulfideazine as foaming agents have been described. The polyurethane foam dressing materials described in these patents generally have a thickness in the range of 0.5 to 20 mm, a water vapor transmission rate of 300 to 5,000 g / m 2/24 hrs (relative humidity of 10 to 100%, 37 ° C.), and open pores. ) Has a size of 30 to 700 µm, an open porosity (open cell ratio) of 20 to 70%, and a thickness of the outer film layer of 12.5 to 37.5 µm.

In addition, U.S. Patent No. 4,773,409 (September 20, 1985) and U.S. Patent No. 4,773,408 (September 25, 1985) have a hydrophilic polyurethane foam dressing material having a thickness in the range of 1 to 10 cm and a density in the range of 0.16 to 0.8 g / cm 3. It is describing. Polyurethane foam dressing materials described in these patents are water-absorbing hydrophilic agents such as sodium carboxymethyl cellulose, calcium carboxymethyl cellulose, pectin, gelatin, guar gum, locust bean gum, collagen, karaya gum, etc. It is made by mixing a Ronon, Water Lock ™, available from Grain Processing Corp., and the like.

In Korean Patent No. 0404140, a polyurethane foam dressing material is manufactured by mixing and stirring a hydrophilic polyurethane prepolymer having an isocyanate terminal, a crosslinking agent, a foaming agent, an additive, and the like, and then injecting the foam into a mold. How to do this is described. However, in order to make a polyurethane foam dressing material of a desired thickness, there is a problem in that a mold having a wide variety of sizes and specifications is required.

In Korean Patent No. 0553078, a hydrophilic polyurethane prepolymer, a crosslinking agent, a foaming agent, and an additive are injected into a large mold, followed by foaming to obtain a polyurethane foam in a block form, and then a skin cutter is removed using a horizontal cutter. It describes a method for producing a polyurethane foam dressing material in a manner of cutting to a constant thickness and then laminating the outer film layer separately. However, the conventional production method of the polyurethane foam dressing material has a limitation of mold foaming. That is, a hydrophilic polyurethane prepolymer having an isocyanate end and a foaming agent is mixed and foamed together with water and other additives at the same time, and molded into a block shape. Since there is a plurality of separate processes to be laminated, there is a problem that the manufacturing process is complicated and thus the productivity and processing efficiency of the product is greatly reduced. In addition, since the foaming occurs immediately when mixing the liquid in the mold and pot life is limited, there are many problems in molding. In addition, the conventional polyurethane foam dressing material as described above has a large open pore size in direct contact with the skin, so that the exudation rate is good, but it fuses with the newly generated skin tissue at the wound site to remove the dressing material from the skin. May cause pain or secondary damage.

Accordingly, the inventors of the present invention provide a non-porous polyurethane film layer that separates outside air from wounds, and a polyurethane foam internal absorbent layer having high absorption force with open pores of 1 to 600 µm in the lower part of the film layer, and fine opening of 1 to 50 µm in the lower part of the inner absorbent layer. A three-layered dressing material including a wound surface contact layer having pores formed to absorb exudates and having a wound surface non-adhesive property is disclosed in Korean Patent Application Nos. 10-2005-0107898 (Patent No. 716658) and No. 10-2006. He was elected as -0026887. Particularly in these patents, hydrophilic polyurethane prepolymers, water, and surfactants are used to solve the problems of the conventional manufacturing methods. It is a new series of manufacturing processes in which a foam mixture is prepared by stirring and then coated on a release paper using a comma coater, etc. with a certain thickness, and then wound in a roll form. I was.

However, the patented technology by the present inventors can raise the productivity surprisingly compared to the prior art, but this also has a pot life is limited, the foaming on the surface of the coating machine after about 2 hours based on the operating time There is a problem in producing a product of a constant thickness as the mixture is hardened over time. In addition, it was pointed out that the rate of absorption of polyurethane foam is poor to absorb the exudate or blood smoothly.

The present invention is to solve the conventional problems as described above, by improving the sheet forming method of the patent application No. 716658, the patent application No. 10-2006-0026887 of the present inventors film layer; An inner absorbent layer; In the production of a foam dressing material having a three-layer structure of wound surface contact layer, it is an object to greatly improve productivity and processing efficiency by a simpler and more efficient new manufacturing process.

In particular, the method described in the present inventors patent 716658 and patent application No. 10-2006-040708 has a limited pot life, and foamed on the surface of the coating machine after about 2 hours of operation time. As the liquid mixture hardened, there were many difficulties in producing a constant thickness product. Accordingly, the present invention aims to innovatively improve the workability by solving the problems of the existing method so as to produce a product having a constant thickness even when working continuously for a long time regardless of pot life.

In addition, the present invention aims to improve the physical properties of the prepared foam dressing material, and particularly aims to greatly improve the absorption rate through the surface modification of the manufactured polyurethane foam.

Other objects and advantages of the present invention will be described below and will be better understood by practice of the present invention.

In the present invention to achieve the above object,

(a) 20 to 70 parts by weight of methyl ethyl ketone and 5 to 30 parts by weight of dimethylformamide are added to 100 parts by weight of the polyurethane resin, followed by mixing, removing bubbles and coating on a release paper, followed by drying to form a non-porous waterproof polyurethane film. Obtaining a layer;

(b) preparing a polyurethane prepolymer which is reacted by adding isocyanate to a mixed solution containing polyol, diol and antioxidant;

(c) preparing a foam composition comprising 60 to 120 parts by weight of deionized water, 0.5 to 40 parts by weight of crosslinking agent, and 1 to 10 parts by weight of surfactant;

(d) mixing 50 to 150 parts by weight of the foamed composition obtained in (c) at 100 parts by weight to 100 parts by weight of the polyurethane prepolymer obtained in (b) to prepare a foamed mixture;

(e) The foam mixture obtained in (d) is supplied onto a release paper fixed to an inclined angle at a predetermined angle, and is foamed while flowing down the inclined surface to form a tack-like gel before curing to a thickness of 1 to 20 mm. Obtaining a polyurethane foam layer;

(f) laminating the polyurethane foam layer obtained in (e) and the non-porous waterproof polyurethane film layer obtained in (a) and pressing a predetermined gap to control the thickness of the foam dressing material. A method for producing a urethane foam dressing material is provided.

The manufacturing method of the present invention preferably further comprises the step of increasing the absorption rate of the foam layer by impregnating and drying the polyurethane foam dressing material obtained in the above (f) with a humectant or by treating with an oxygen plasma. In addition, the manufacturing method of the present invention may further comprise the step of aging the polyurethane foam dressing material after the lamination step in a hot air dryer. In addition, the foam composition may further comprise 0.01 to 20 parts by weight of the drug.

In addition, in the present invention, a method for producing a hydrophilic foam dressing material comprising the step of impregnating and drying the polyurethane foam dressing material in the humectant or treating the oxygen plasma to increase the absorption rate of the foam and thus prepared hydrophilic foam dressing material do.

According to the present invention, a foamed mixture is prepared by mixing a hydrophilic polyurethane prepolymer with deionized water, a surfactant, a crosslinking agent at a high speed, and then foaming the foamed mixture at an angle to discharge onto a release paper treated with fixed silicon. The mixed solution flows down the inclined release paper and starts foaming. Then, the foam dressing material is uniformly gapped before laminating and curing the moisture-permeable polyurethane film layer in a tack-like gel state. By manufacturing the polyurethane foam dressing material with a new manufacturing method of adjusting the thickness by pressing), the productivity and processing efficiency of the foam dressing material can be greatly improved, and above all, it is not limited by pot life, Mass production is possible and production cost is greatly reduced, so foam dressing material at low cost It can offer.

In addition, by impregnating and drying the prepared polyurethane foam in the humectant to improve the absorption rate by treating the oxygen plasma, it is possible to supply a polyurethane foam dressing material with enhanced functionality, and also the treatment time of oxygen plasma and the presence or absence of humectant impregnation By adjusting the absorption saturation time of the foam dressing material by adjusting the surface modification conditions such as concentration, it can be customized to the polyurethane foam dressing material having an absorption rate suitable for various wound conditions and conditions.

The present invention significantly improves the productivity of foam dressing materials by a new and efficient process, and at the same time, it is superior to expensive foam dressing materials manufactured by conventional methods in terms of physical properties, and easy to form into various sizes and shapes. Can provide.

As used herein, "hydrophilic polyurethane" refers to a polyurethane in which a hydrophilic group is introduced to exhibit hydrophilicity as compared to general polyurethane. In addition, in the present specification, "moisture permeable film" refers to a polyurethane film manufactured to have moisture permeability compared to a general polyurethane film using a hydrophilic polyurethane into which a hydrophilic group is introduced. In addition, in the present specification, "moisture-permeable water-proof film" or "moisture-permeable water-proof film" refers to a polyurethane film manufactured to have both moisture permeability and water resistance using a hydrophilic polyurethane into which a hydrophilic group is introduced.

Method for producing a polyurethane foam dressing material according to the invention comprises the steps of preparing a moisture-permeable waterproof polyurethane film layer; Preparing a polyurethane prepolymer; Preparing a foam composition; Preparing a foam mixture; Adjusting the thickness of the foam dressing material while laminating the polyurethane foam layer and the polyurethane film layer in a tack gel state; Optionally or totally including a surface modification step and a maturing step to increase the rate of absorption of the foam layer. Hereinafter, each step will be described in detail.

Breathable  Preparation of Polyurethane Film Layers

20 to 70 parts by weight of methyl ethyl ketone and 5 to 30 parts by weight of dimethylformamide are added to 100 parts by weight of the polyurethane resin, followed by stirring to remove air bubbles, applied to a release paper, and dried to form a non-porous waterproof polyurethane film layer. At this time, if necessary, 1 to 10 parts by weight of the pigment may be further added to the polyurethane resin. In one embodiment of the present invention by degassing with a vacuum stirring deaerator to remove bubbles. The foamed polyurethane solution is coated on a matte release paper with a coating gauge or the like and dried to obtain a non-porous polyurethane film layer. At this time, the polyurethane resin having both moisture permeability and water resistance as the polyurethane resin, that is, the polyurethane resin having a hydrophilic group introduced into the main chain, similarly to the polyurethane resin used to form the polyurethane foam layer, has both moisture permeability and water resistance. A moisture-permeable waterproof polyurethane film layer is obtained. This polyurethane film layer forms the outer side of the dressing material produced according to the invention.

Polyurethane Prepolymer  Produce

Isocyanate is added to a mixed solution containing a polyol, a diol, and an antioxidant to prepare a polyurethane prepolymer.

Specific preparation examples of the polyurethane prepolymer are as follows. First, a polyol and a diol are added, the stirring rate is 150 rpm, the temperature is raised to 50 ° C., and the mixture is stirred for 30 minutes. Then, an isocyanate is added, and the NCO content (%) reaches the theoretical value under nitrogen atmosphere. React until.

As the polyol, for example, polypropylene oxide glycol; Polyethylene oxide glycol; Polytetramethylene ether glycol; Ethylene oxide / propylene oxide copolymers; Polytetrahydrofuran / ethylene oxide copolymers; Polytetrahydrofuran / propylene oxide copolymers; Polybutylene carbonate glycol; Polyhexamethylene carbonate glycol; Polycaprolactone glycol; Polyethylene adipate; Polybutylene adipate; Polyneopentyl adipate; Polyhexamethylene adipate and the like may be used alone or in combination of two or more thereof.

The polyurethane prepolymer used to prepare the polyurethane foam of the present invention is preferably a hydrophilic polyurethane prepolymer having a hydrophilic group introduced therein. The hydrophilicity is important for the content of ethylene oxide, a hydrophilic group, which is described in “Journal of Cellular Plastics 1976; 12; 285 ”“ Journal of Cellular Plastics 1983; 19; 259 ”, US Pat. No. 4,008,189 (1975.11.4) and the like. Therefore, most preferably, an ethylene oxide / propylene oxide copolymer having a molecular weight of 500 to 6,000 having two or more hydroxyl groups as the polyol is preferably used having an ethylene oxide content of 20% to 90%.

As the isocyanate, aromatic, aliphatic and substituted isocyanates or mixtures thereof may be used. For example, 2, 4- toluene diisocyanate; 2,6-toluene diisocyanate; Methylenediphenyl diisocyanate; 1,5-naphthalene diisocyanate; Toridine diisocyanate; Hexamethylene-1,6-diisocyanate; Isophorone diisocyanate; Xylene diisocyanate; Cyclohexylene-1,4-diisocyanate; Lysine diisocyanate; Tetramethylene-xylene diisocyanate can be used individually or in combination of 2 or more types. Preferably isophorone diisocyanate; 2,4-toluene diisocyanate; 2,6-toluene diisocyanate; Methylene diphenyl isocyanate and the like are used.

As said diol compound, Ethylene glycol; Propylene glycol; 1,3-butanediol; 1,4-butanediol; 1,5-pentanediol; 1,6-hexanediol; Triethylene glycol; Diethylene glycol; Tetraethylene glycol; Dipropylene glycol; Dibutylene glycol; Neopentyl glycol; 1,4-cyclohexanedimethanol; 2-methyl-1,3-pentanediol or the like may be used alone or in combination of two or more thereof. Preferably ethylene glycol; Propylene glycol; Any one or 1 or more of 1,4-butanediol is used together. The diol compound acts as a chain extender in the prepolymer to increase the molecular weight of the prepolymer and to increase the hard segment content to increase mechanical properties. However, if too much amount is added, the viscosity of the prepolymer becomes high, so that it is not uniformly mixed with the foaming composition in preparing the foamed mixed solution. In addition, if the viscosity is synthesized too high, the polyurethane prepolymer and the foaming composition are mixed and stirred, so that the flowability is not good when supplied on the inclined release paper, the molding is not easy. Conversely, if it is too low, it will flow too quickly on the inclined release paper, which is also difficult to mold. Preferably, the viscosity of the prepolymer synthesized by adding the diol compound is preferably 3,000 to 20,000 cps (30 ° C). However, this can be easily adjusted by those skilled in the art according to the situation such as the viscosity and the molding temperature of the foam composition.

In addition to the preparation of the polyurethane prepolymer of the present invention, known known additives can be added by known methods. Such additives include, in particular, antioxidants. As the antioxidant, for example, phenyl-beta-naphthalamine; Cysteine hydrochloride; Dibutylhydroxytoluene; Nordihydroguazaletic acid; Butylhydroxyanisole; Phosphoric acid; Citric acid; Ascorbic acid; Erythorbic acid; Propyl gallic acid, IRGANOX 1010 from Ciba Specialty Chemicals; IRGANOX 1035; IRGANOX 1076; IRGANOX 1330; IRGANOX 1425WL; IRGANOX 3114; IRGANOX B215; IRGANOX B220; IRGANOX B225; IRGANOX B561; IRGANOX B313; IRGANOX B501W; IRGANOX B900; IRGANOX B1411; IRGANOX B1412; IRGANOX PS800; IRGANOX PS802; IRGAFOS P-EPQ or the like may be used. Preferably phosphoric acid; Citric acid; Dibutylhydroxytoluene; Butylhydroxyanisole; IRGANOX 1010; IRGANOX 1035; IRGANOX 1076; Any one or two or more of IRGANOX 1330 are used together. Antioxidants may be added in the range of 0.05 to 5% by weight of the total weight of the polyurethane prepolymer.

Preparation of foam composition

Water, a crosslinking agent, a surfactant, etc. are mixed to prepare a foaming composition to be used as a blowing agent. The foamed composition is 60 to 120 parts by weight of deionized water; 0.5-40 weight part of crosslinking agents; It contains 1 to 10 parts by weight of the surfactant, and may further comprise 0.01 to 2 parts by weight of the pigment, 0.01 to 20 parts by weight of the drug, 0.1 to 40 parts by weight of the humectant and absorbent aid.

Crosslinking agents include glycerin; Trimethylolpropane; 1,2,4-butanetriol; Sorbitol etc. can be used individually or in combination of 2 or more types. The crosslinking agent serves to improve the mechanical properties of the foam through the crosslinking reaction during polyurethane foam formation.

As the surfactant, known surfactants can be used according to known uses and methods. For example, BASF's F-68 which is an ethylene oxide / propylene oxide block copolymer; F-87; F-88; F-108; F-127 and L-580 as a silicone type surfactant; L-603; L-688; L-5420; SZ-1703; L-6900; L-3150; Y-7931; L-1580; L-5340; L-5333; L-6701; L-5740M; L-3002; L-626 can be used. The surfactant serves to control the size of the pores of the wound surface contact layer 11 and the inner absorbent layer 12 and the opening ratio of the pores of the polyurethane foam dressing material. In particular, BASF's F-68, an ethylene oxide / propylene oxide block copolymer, is known to help clean wounds without causing injury to tissues and is known to be non-toxic, and thus may be used as the most preferred surfactant.

In the present invention, the moisturizing agent maintains a moist environment on the wound surface to suppress the formation of the skin and serves to smooth the wound healing. Accordingly, the term "humidant" is used as a meaning including a well-known moisturizer generally known as a moisturizer, as well as a wound healing aid that maintains a moist environment to suppress the formation of the skin and facilitate wound healing. Specific examples of such moisturizing agents include propylene glycol alginate; Methyl cellulose; Carboxymethyl cellulose sodium; Carboxymethyl cellulose calcium; Carboxymethyl starch sodium; Sodium alginate; Ammonium alginate; Potassium alginate; Calcium alginate; Sodium caseinate; Guar gum; Locust bean gum; Xanthan gum; Cyclodextrins; Gum arabic; Gellan gum; Carrageenan; Karaya gum; Casein; Tara gum; Tamarind gum; Tragacanth gum; pectin; Glucomannan; Gati gum; Arabinogalactan; Purselane; Pullulan; Glococosamine; Carboxymethyl cellulose; Chitin; Chitosan; Sodium alginate; Hyaluronic acid; amino acid; L-aspartic acid; Sodium L-aspartate; DL-alanine; L-isoleucine; Lysine hydrochloride; Glycine; glycerin; L-glutamine; L-glutamic acid; Sodium L-glutamate; Pyridonic acid; L-threonine; Sericin; Serine; L-tyrosine; Heparin; Sodium chondroitin sulfate; Sodium alginate; Gelatin and the like can be included in the foamed mixture according to known dosages and methods within this range.

The use of cellulose additives such as carboxymethyl cellulose in the moisturizing agent can improve the mechanical properties compared to products without addition. It acts as a filler, which is a substance added for the purpose of anti-aging, reinforcement, and increase in the practical use of rubber or plastic. For example, in urea formalin resin, phenol formalin resin, and synthetic leather, the polyurethane film may not have sufficient strength as a resin but only by adding cellulose, asbestos, wood flour, etc., the resin is reinforced with mechanical properties.

In the present invention, "drug" is meant to include all known drugs and antibacterial agents known to have a wound healing effect, as well as wound healing aids that have bacteriostatic or granulative growth. Thus, sugars known to have bacteriostatic and granuloproliferative action may also be included as drugs in the present invention. Such saccharides include sucrose; Sorbitol; Mannitol; fruit sugar; glucose; Xylitol; Lactose; Maltose; Maltitol; There are trehalose, etc., as a wound healing aid that plays a role in granulation, fibroblast growth factor (FGF), hepatic fibrosis growth factor (HGF), epidermal cell growth factor (EGF) may be used.

The composition may include a drug, in particular a natural substance known to have anti-inflammatory, antibacterial, antifungal action or skin regeneration effect. Such materials include, for example, tea tree oil, Sophora Angustifolia Extract, Iris Extract, Licorice Extract (Glycyrrhiza Glabra Extract), bioflavonoids derived from grapefruit (seed) extract. Bioflavonoids); Naringin; Polypeptides; Asiatic acid from Tocopherols, Centella Asiatica; Madecaic Acid, β-Glucan Extracted from Mushroom, Neem Extract, Witch Hazel Extract, Allantoin, Portulace Oleracea Extract Plant-derived natural substances, such as Ponciri Fructus Extract, Phytosphingosine, Aloe Extract. Such natural materials may be included in the composition alone or in combination of two or more within the above ranges according to known dosages and methods.

In addition, known antibacterial agents can be used to prevent infection and proliferation of various bacteria with the drug. For example, sulfadiamine is known to be known as povidone iodine, iodine, iodide ion salt, pladiomycin sulfate, acrinol, chlorohexidine, benzalkonium chloride, benzenetonium chloride, fusidic acid, and salts thereof. It may be included in the composition within the above range depending on the dose and method.

In addition, known medicines may be included in the dressing material of the present invention as necessary for treatment and prevention purposes.

In addition, the composition may include an absorption aid such as a known super absorbent polymer (Super Absorbent Polymer) to increase the absorbency of the polyurethane foam within the above range.

In addition to the foaming composition of the present invention, a known additive such as a stabilizer, a preservative, a physical property regulator, etc., which are known in efficacy, may be added in a small amount for a known purpose.

Preparation of foam mixture and molding of polyurethane foam layer

50 to 150 parts by weight of the foaming composition is stirred at a high speed to 100 parts by weight of the polyurethane prepolymer prepared in the above step, and is fed onto the silicon-treated release paper 30A which is inclined at a predetermined angle. The foamed mixed solution supplied flows down the inclined side of the release paper and at the same time foaming starts to form a polyurethane foam layer. At this time, the release paper is preferably fixed to be inclined so as to maintain an angle of 30 degrees to 70 degrees with respect to the straight line to which the foamed mixture is supplied. If the inclination of the release paper is less than 30 degrees, the foamed mixed solution does not flow easily on the release paper, so that the molding is not easy, and if it is 70 degrees or more, the foamed mixed solution flows along the inclined surface too quickly, making molding difficult. In the present invention, it is possible to continuously produce a product having a predetermined thickness without limiting the pot life because the foam mixture is supplied to the release paper using the constant inclined surface. FIG. 12 shows that the foamed mixed solution is supplied onto the release paper 30A which is inclined at an angle d.

The foam layer thus formed is preferably subjected to the next step of lamination in a tack gel state before curing. That is, after forming a polyurethane foam layer in a state of sticky tack like a gel on a release paper, the lamination is performed with the polyurethane film layer immediately, thereby using an adhesive or an adhesive. The process can be achieved simply by laminating without additional process.

The release paper used in this step is preferably to use a polymer film or paper release paper surface-treated with silicon.

Lamination (Production of Polyurethane Foam Dressing Material)

The polyurethane foam layer prepared in the above step and the polyurethane film layer are laminated and pressed with a certain gap to adjust the thickness of the foam dressing material. In this case, as described above, the polyurethane foam layer and the polyurethane film layer in a tacky gel state before curing are simply laminated without using an adhesive or an adhesive. However, the lamination method of the present invention is not limited thereto, and a known lamination method using an adhesive or an adhesive or applying pressure may also be used.

Preferably, after laminating the polyurethane film layer, the film is dried for about 1 minute in a hot air dryer at about 100 ° C., and then the release paper in contact with the polyurethane film layer is peeled off. After the hot air drying, it is good to enter the next aging step. The reason for this is that if the hot air dryer is used as it is, without hot air drying, the polyurethane foam dressing material shrinks and curling occurs. This is because it is difficult to wind up and also prevents the moisture remaining in the polyurethane foam layer from being volatilized. If the moisture is not volatilized properly, there is a problem that the exudation capacity and the absorption rate of the exudates of the contact surface of the polyurethane foam dressing material is lowered. When the release paper in contact with the film layer after the hot air drying in this manner is peeled off, the polyurethane foam dressing material of the present invention in a state where the release paper is attached only to the foam layer is obtained. The release paper in contact with the polyurethane foam layer is peeled off at the time of use of the patient so that the surface on which the release paper is removed is in contact with the wound site.

In an embodiment of the present invention, the polyurethane prepolymer and the foaming composition are stirred at a high speed of about 3,000 rpm, and then the foamed mixture is supplied onto a release paper fixed to an inclined angle at an angle, and the slanted surface flows about 2 minutes. After that, a layer of tack-free polyurethane foam began to form. At this time, the water-permeable water-resistant film and the surface of the paper (the surface without release paper) were brought into contact with each other and directly laminated, and dried in a 100 ° C. hot air dryer for 3 minutes.

ferment

Polyurethane foam dressing material subjected to the lamination step is preferably further subjected to a step of aging in a hot air dryer.

In one embodiment of the present invention, the polyurethane foam dressing material in a state of peeling the release paper in contact with the film layer after hot air drying in the above step is aged in a hot air dryer at 50 ~ 70 ℃ for a certain time. After aging for a certain period of time, the polyurethane foam dressing material shrinks to some extent. At this time, the polyurethane outer film layer shrinks together, resulting in a natural wrinkle pattern. The same effect can be obtained by using a release paper such as a wrinkled release paper AR-175 (Asahirol Co., Ltd.). In addition, aging may also increase the mechanical properties such as tensile strength and elongation.

Surface Modification of Polyurethane Foam

The polyurethane foam prepared in the above step is impregnated with the humectant and / or dried, and then treated with oxygen plasma to increase the hydrophilicity of the polyurethane foam, thereby increasing the absorption rate.

As the humectant, for example, glycerin; Triacetin; Propylene glycol; Sorbitol; Polyethylene glycol and the like may be used alone or in combination of two or more thereof. In the case of glycerin, the higher the concentration of glycerin, the greater the pretreatment effect. Preferably, the solution is impregnated with 100 parts by weight of 50% aqueous ethanol and 5-20 parts by weight of glycerin, followed by drying. In addition to ethanol, methanol, isopropyl alcohol, and the like can also be used. Most preferably, ethanol is used.

Oxygen plasma treatment is preferably about 10 seconds to 2 minutes, more preferably 30 seconds to 60 seconds.

Surface modification may be carried out by selecting only one of the humectant treatment or oxygen plasma treatment, and may be performed in combination with the two treatments by treating the oxygen plasma after the humectant treatment. In terms of effects, the two treatments are preferably combined. This surface modification is preferably carried out in the last step after completing the foam dressing material through the above steps. However, the present invention is not limited thereto, and the foam layer may be prepared at an appropriate stage as necessary.

In one embodiment of the present invention, the polyurethane foam was fixed on the sample holder, and the inside of the reactor was vacuumed using a rotary pump. The internal pressure of the reactor was adjusted while injecting a certain amount of oxygen using the flow controller. After the pressure was fixed at 250 mTorr, oxygen was injected for about 10 minutes, and oxygen plasma was generated for about 30 to 60 seconds to treat the surface of the polyurethane foam.

11a to 11c is a graph showing the absorption rate behavior of the polyurethane foam dressing material according to the present invention. As shown in the graph, as the treatment time of the oxygen plasma was increased, the time to reach the absorption saturation state of the polyurethane foam dressing material was found to be faster. In addition, treatment with oxygen plasma after impregnation and drying of a humectant such as glycerin showed that the time to reach absorption saturation was faster than that without humectant pretreatment. In addition, in FIG. 11C, even when the oxygen plasma treatment is not performed, the time to reach the absorption saturation state becomes faster as the dried one is impregnated with a solution having a high concentration of glycerin as a humectant.

Structure of polyurethane foam dressing material

Polyurethane foam dressing material of the present invention produced by the above method will have a foam layer and a polyurethane film layer made of polyurethane foam, the foam layer is divided into two layers again. Hereinafter, with reference to the accompanying drawings will be described the structure of the polyurethane foam dressing material according to the present invention.

1A to 1D are schematic views of a polyurethane foam dressing material produced according to the present invention. Figure 1a is a cross-sectional schematic of the polyurethane foam dressing material, consisting of a foam layer 10 made of polyurethane foam foam and a waterproof polyurethane outer film layer 20, the foam layer 10 is again 1 ~ 50㎛ diameter It has a natural two-layer structure of the skin contact layer 11 having fine open pores and the internal absorbing layer 12 having a plurality of open pores having a diameter of 1 to 1,000 μm. In addition, the open pores have a structure having a plurality of pores (Pore) that specifically penetrates the open pores. It consists of 1-50 micrometers in average diameters of pores.

FIG. 1B is a schematic view of a polyurethane film layer 20 prepared by defoaming a polyurethane resin with a vacuum stirring deaerator to remove bubbles, applying a predetermined thickness on a matte release paper 30B, and then drying (Dry). At this time, if a polyurethane resin having both moisture permeability and water resistance as a polyurethane resin, that is, a polyurethane resin having a hydrophilic group introduced into the main chain, such as a polyurethane resin used to form a polyurethane foam layer, has moisture permeability and water resistance at the same time A waterproof polyurethane film layer is obtained.

Figure 1c is a foamed polyurethane foam layer 10 of mixing the polyurethane prepolymer and the foaming composition was stirred at a high speed, and then tilted at a constant angle to supply a release paper 30A treated with a fixed silicone to flow down It is a schematic diagram. In the foam layer, a skin layer is formed on the surface where the mixed solution mixed with the prepolymer and the foam composition is in direct contact with the silicone release paper 30A, thereby naturally forming two layers (11, 12) due to the difference in pore state of the surface. It is divided into, the surface portion in contact with the release paper (30A) is made of fine pores than the film form (skin layer). The surface portion in contact with the release paper on which finer open pores are formed is called the wound surface contact layer 11, and the portion where the larger and larger open pores are formed is called the absorber layer 12. The absorbent layer is responsible for the main absorbent function in the polyurethane dressing material of the present invention.

1D is a schematic diagram of a polyurethane foam dressing material with a release paper attached thereto, wherein the release paper 30B attached to the film layer 20 is peeled off during manufacture, and the release paper 30A attached to the foam layer 10 is in use. Is removed.

In the foam dressing material of the present invention, the wound surface contact layer 11 has micropores having a diameter of 1 to 50 µm, serves to absorb exudates, and has wound surface non-adhesive properties. The inner absorbent layer 12 has a plurality of open pores having a diameter of 1 to 1,000 μm, can absorb and store 100 to 1,000 wt%, and has a density of 0.1 to 0.8 g / cm 3. And these pores have a structure having a pore (Pore) of the average diameter of 1 ~ 50㎛ penetrating the pores again. The outer film layer 20 is a moisture-permeable waterproof film, having a high moisture permeability of 400 to 3,000 g / m 2 / day (relative humidity 10 to 90%, 37 ° C., Desiccant Method), and bacteria (bacteria) and bacteria from the outside. It prevents the invasion of, prevents the leakage of exudates, and creates a moist environment on the wound surface.

1A to 1D are merely exemplary forms of the polyurethane foam dressing material according to the present invention, and the dressing material of the present invention may be manufactured in various sizes and shapes depending on the use and need.

Hereinafter, the present invention will be described in more detail with reference to specific examples. However, the scope of the present invention is not limited by the following examples, and those skilled in the art to which the present invention pertains should be within the equivalent scope of the technical concept of the present invention and the claims to be described below. Of course, various modifications and variations are possible.

Polyurethane Prepolymer Synthesis Example (# 1 to 3)

The polyurethane prepolymer was synthesized according to the conditions and methods shown in Table 1 below.

As shown in Table 1, it can be seen that the viscosity of the synthesized polyurethane prepolymer increases as a chain extender such as ethylene glycol or 1,4-butanediol is added or the content of hard segment increases.

Moisture-Proof Polyurethane Synthesis Example

Next, the moisture-permeable waterproof polyurethane resin was synthesized under the conditions and methods of Table 2.

Breathable  Polyurethane film Production Example

The moisture-permeable waterproof polyurethane film was prepared by mixing and stirring 50 parts by weight of methyl ethyl ketone, 15 parts by weight of dimethylformamide, and 5 parts by weight of pigment to 100 parts by weight of the water-repellent waterproof polyurethane resin prepared in Table 2 to prepare a polyurethane mixed solution. .

The prepared polyurethane mixture was applied to the matte release paper 30B (Yulchon Chemical Co., Ltd.) using a thickness gauge at a constant thickness, and then dried in a 100 ° C. hot air dryer for 30 minutes to provide moisture-permeable water-resistant poly on one side of the matte release paper 30B. A urethane film was formed. The thickness of the moisture-permeable waterproof polyurethane film produced in this manner was 20 μm.

Foam composition Production Example (# 1 to 3)

To prepare a foam composition # 1, # 2, # 3 under the same conditions as Table 3.

Polyurethane foam dressing material manufacturing example (# 1-21)

(1) Polyurethane foam dressing material is 100 parts by weight of the polyurethane prepolymer prepared in the synthesis example and 80 parts by weight of the foamed composition prepared in the foam composition prepared by stirring for 10 seconds at 3,000rpm inclined at an angle of 45 degrees It was supplied on release paper A (Yulchon Chemical Co., Ltd.) to cause the foamed mixture to flow along the inclined surface. The prepolymer, foam composition and processing conditions used in each preparation example are shown in Table 4 below.

(2) When 2 minutes have elapsed after allowing the foam mixture to flow down, the polyurethane foam layer in a gel state having a tackiness becomes a certain thickness. The 20-micrometer-thick film which was prepared was laminated | stacked with fixed thickness gap (Gap). Subsequently, to control the thickness of the product was pressed with a certain thickness gap (Gap) and dried for 3 minutes in a 100 ℃ hot air dryer. The thickness and mechanical properties of the polyurethane foam layer before aging are shown in Table 4 below.

(3) After drying, the matte release paper (B) on which the moisture-permeable waterproof polyurethane film was formed was peeled off and aged in a 70 ° C. hot air dryer for 24 hours, the thickness of the polyurethane foam dressing material and the thickness of the outer film layer, and the mechanical properties after aging. Physical properties are shown in Table 4 below.

Oxygen Plasma Treatment Example

The surface of the polyurethane foam dressing material prepared in the above preparation was treated for 30 seconds and 60 seconds using an oxygen plasma reactor (Model EPPS 2000, PLASMART Inc.), respectively. At this time, the pressure was fixed at 250 mTorr, the internal pressure of the reactor was measured by a vacuum gauge (Model 801, Varian), the flow rate of the inlet gas was used a mesflow controller (MFC, Brooks, Japan, Model 5850E). Plasma generation confirmed the stability from the color light inside the reactor. Oxygen plasma treatment time of each preparation example is shown in Table 4 below.

Wetting Agent Treatment Example

5 parts by weight of glycerin, 10 parts by weight of glycerine, and 20 parts by weight of glycerin were mixed into 100 parts by weight of a 50% aqueous solution of ethanol to impregnate the polyurethane foam dressing material prepared in Preparation Example for 1 minute. After drying for 24 hours in an 80 ℃ vacuum dryer. The concentration of glycerin treated in each preparation example is shown in Table 4 below.

Test Example

The physical properties of the polyurethane foam dressing material prepared in the above production example and the polyurethane foam dressing material of the following comparative example were measured by the method exemplified below, and the measured experimental results are shown in Table 5 below. In addition, the internal structures of the polyurethane foam dressing material and the commercial polyurethane foam dressing material of the present invention were observed with a scanning microscope and shown in FIGS. 2 to 10. In addition, the absorption rate behavior of the finally prepared polyurethane foam dressing material is shown graphically in FIG.

① Mechanical Properties (tensile strength, elongation)

Load cell 50N, specimen width 20mm, specimen using universal test machine (Instron) to measure the mechanical properties of polyurethane foam layer without laminating moisture-permeable polyurethane outer film layer Gauge Length was measured as 30 mm and Cross Head Speed as 100 mm / min.

② Absorption Saturation Rate (sec)

The dressing material was taken in a size of 3 cm × 3 cm, left at room temperature for 24 hours, and then impregnated and stored in 37 ° C. distilled water to measure the time until no further weight change.

③ moisture permeability

Using a thermo-hygrostat (SAMHEUNG INSTRUMENT, SH-CTH150) was measured according to ASTM E 96-94 (Desiccant Method), wherein the thermo-hygrostat was 37 ℃ ± 2 and the relative humidity was 80% ± 5.

④ Morphology

Scanning electron microscope was used to measure the shape of open cells and pores of the polyurethane foam dressing material of the present invention and the thickness of the film layer.

Comparative example  One

Commercially available Care Foam ™ (Saeron Pharmaceuticals) was used for the comparison of properties. Physical properties were measured by the method exemplified in the above Preparation Example and the results are shown in Table 5 below.

Comparative example  2

Commercial allelevin ™ (Smith & Nephea) was used in the experiment for physical property comparison. Physical properties were measured by the method exemplified in the above Preparation Example and the results are shown in Table 5 below.

As shown in Table 5 and Figs. 11A to 11C, it can be seen that the time to reach the absorption saturation is faster as the oxygen plasma treatment is performed under the same conditions. Faster time to absorption saturation means that the time to absorb the exudate quickly and retain as much of the exudate as possible is fast. Absorption equilibrium was found to be 115 sec in the case of Preparation Example 7 without the wetting agent and the oxygen plasma, but Preparation Example 8 with 30 seconds treatment of oxygen plasma was much faster at 85 sec and 60 seconds treatment. One Preparation Example 9 was faster than Preparation Example 7 which was not treated in 70 seconds. In addition, in the case of Preparation Examples 11 and 12, in which the oxygen plasma was treated after wet treatment with a solution containing 5 parts by weight of glycerin in 100 parts by weight of 50% ethanol solution, compared to Preparation Examples 8 and 9, in which only the oxygen plasma was treated. Were accelerated to 70 seconds and 60 seconds respectively. In addition, Preparation Examples 13 and 14 show that the time to reach the absorption saturation state can be accelerated only by pretreatment by increasing the content of the humectant such as glycerin and drying without oxygen plasma treatment. Therefore, it can be seen that the absorption saturation time can be controlled by adjusting the treatment time of oxygen plasma and the concentration of the wetting agent.

In addition, when manufacturing a polyurethane prepolymer is synthesized in Examples 1 to 7, when a chain extender such as ethylene glycol or 1,4-butanediol is added, the mechanical properties become constant as the content of the hard segment increases. It can be seen that it is improved, and the speed to the absorption saturation rate is found to increase constantly. In addition, it can be seen that when a triol compound such as glycerin is added as a crosslinking agent, the degree of crosslinking is increased to improve mechanical properties. Therefore, it can be seen that the mechanical properties can be controlled depending on the content of the hard segment and the presence or absence of the crosslinking agent.

If you look at the production examples 15, 16, 17 and press the thickness control gap (Gap) a lot of manufacturing, the size of the open cells (pore) gradually decreases the number of pores (pores) through the open pores, the absorption saturation rate However, when looking at Preparation Examples 18, 19, 20 it can be seen that the absorption saturation rate can be improved by oxygen plasma treatment or wetting agent pretreatment. In addition, the more the thickness control gap is pressed, the smaller the overall pore size and pore size, and the higher the density of the foam.

In addition, looking at Preparation Examples 1 and 3, the addition of carboxymethyl cellulose in the foam composition under the same conditions was found to increase the mechanical properties than the other.

Therefore, it is possible to control the mechanical properties of the polyurethane foam dressing material produced by the chain extender, the content of the hard segment, the presence or absence of crosslinking agent, powder additives such as carboxymethyl cellulose, gap control in the thickness control unit, and the like. In addition, it can be seen that the polyurethane foam dressing material having various physical properties and properties can be produced by oxygen plasma treatment or humectant treatment.

2 to 5 are scanning electron micrographs of the polyurethane foam dressing material according to the present invention. FIG. 2 shows Preparation Example 15, FIG. 3 shows Preparation Example 16, and FIG. 4 shows Preparation Example 17 and FIG. 5 shows Preparation Example 21. to be. In the photograph, A is a photograph of the inner absorbent layer 12, and B is a photograph of the wound surface contact layer 11. It can be seen that the inner absorbent layer has a larger number of open pores and pores penetrating the pores than the wound surface contact layer. In addition, the more pores formed by pressing the thickness control gap, the smaller the size of the open pores of the absorbent layer, the more the skin layer of the contact layer is on the wound, and the shape of the pores changes from circular to oval, and the number of pores penetrating the pores. You can see it shrinks. Such a structure may be ineffective in absorbing exudate, but this is not a problem because it can increase the rate of absorption saturation through surface modification such as humectant pretreatment or oxygen plasma treatment.

FIG. 6 is a scanning electron micrograph of Mediform-en ^TM of Ildong Pharmaceutical Co., Ltd. as a commercially available polyurethane foam dressing material (LOT.01N22506, date of manufacture: 060207, Korea). If you look at the internal absorption layer “A”, it has a structure of constant and fine pores, and if you see the “B” contact surface of the wound, there are many skin layers (S) without pores, and the size of the pores is very large compared to other products. Small, the difference is clearly distinguished.

7 is a scanning electron micrograph of Mediform-F ^™ manufactured by Ildong Pharmaceutical as a polyurethane foam dressing material, which is commercially available (LOT.02F01007, date of manufacture: 070405, Korea). This is a product in which the skin layer is removed using a horizontal cutter after making into a block-type product using a mold. Both the inner absorbent layer and the wound contact layer have the same structure. However, if the pores of the wound surface contact layer are too large or too large, the open pores of the surface directly contacting the skin are large, so that the exudation rate is improved, but the dressing material is fused with the newly formed skin tissue at the wound site. When removed from there is a problem that can cause pain or secondary damage.

FIG. 8 is a scanning electron micrograph of Allvin ( ^TM ) of SmithNenefuse using a commercially available polyurethane foam dressing material (LOT.0611 60229, manufactured date: 060313, UK). Like other things, it consists of open pores and pores penetrating open pores, and the pores are somewhat larger in size. In addition, when the wound surface contact layer “B” is seen, a net polymer film is laminated to form a skin layer (S).

9 is a scanning electron micrograph of the absorbent layer and the wound surface contact layer of Care Foam ^TM with a polyurethane foam dressing material of Salon Pharmaceuticals, a commercial product (LOT. C05002, date of manufacture: 051222, South Korea). It looks like Figure 7, but the size and shape of the pores is irregular compared to Figure 7. In addition, there is also a problem that can cause pain or secondary damage when the dressing material is removed from the skin by fusion with the newly generated skin tissue at the wound site because the pore size of the wound surface contact layer is very large and very large.

FIG. 10 is a scanning electron micrograph of Colotlast's Viataine ^TM (LOT. 743794, date of manufacture: 2006.3, Denmark) with a commercially available polyurethane foam dressing material. Looking at the inner absorbent layer, the structure of the pores similar to the product of FIG. 8 is shown. However, the wound surface contact layer is a form having a plurality of pores including a little skin layer (S).

As described above, the polyurethane foam dressing material manufactured according to the present invention shows a wide variety of shapes compared to other conventional products, and can be custom-made with a polyurethane foam dressing material having an absorption rate and a suitable structure suitable for various wound conditions and conditions. have. In addition, the hydrophilicity of the polyurethane foam dressing material can be adjusted by performing surface modification treatment such as wetting agent pretreatment, oxygen plasma treatment, and the like as necessary.

1A to 1D are schematic views of a polyurethane foam dressing material according to the present invention.

Figure 2 is a scanning electron micrograph of the absorbent layer and the wound surface contact layer of the polyurethane foam dressing material of Preparation Example 15 according to the present invention.

3 is a scanning electron micrograph of the absorbent layer and the wound surface contact layer of the polyurethane foam dressing material of Preparation Example 16 according to the present invention.

4 is a scanning electron micrograph of the absorbent layer and the wound surface contact layer of the polyurethane foam dressing material of Preparation Example 17 according to the present invention.

5 is a scanning electron micrograph of the absorbent layer and the wound surface contact layer of the polyurethane foam dressing material of Preparation Example 21 according to the present invention.

FIG. 6 is a scanning electron micrograph of Mediform-N ^TM of Ildong Pharmaceutical Co., Ltd.

7 is a scanning electron micrograph of Mediform-F ^™ manufactured by Ildong Pharmaceutical.

FIG. 8 is a scanning electron micrograph of Allvin® ^TM of Smith & Nephew commercially available.

Figure 9 is a scanning electron micrograph of a commercial product Salon Pharmaceuticals Care Foam ^TM .

FIG. 10 is a scanning electron micrograph of Coateplast's Viataine ^™ , commercially available.
11a to 11c is a graph showing the absorption rate behavior of the polyurethane foam dressing material according to the present invention.

12 is a view showing that the foam mixture is supplied on the release paper (30A) fixed inclined in accordance with the present invention.

<Description of Symbols for Major Parts of Drawings>

10: foam layer in which open pores are formed

11: wound surface contact layer 12: internal absorption layer

P: Pore O: Open Cell

20: non-porous waterproof outer film layer F: outer film layer

S: Skin Layer 30A, 30B: Release paper

d: inclination angle of the release paper 40: foam mixture supply portion

Claims (18)

(a) 20 to 70 parts by weight of methyl ethyl ketone and 5 to 30 parts by weight of dimethylformamide are added to 100 parts by weight of the polyurethane resin, followed by mixing, removing bubbles and coating on a release paper, followed by drying to form a non-porous waterproof polyurethane film. Obtaining a layer; (b) preparing a polyurethane prepolymer which is reacted by adding isocyanate to a mixed solution containing polyol, diol and antioxidant; (c) preparing a foam composition comprising 60 to 120 parts by weight of deionized water, 0.5 to 40 parts by weight of crosslinking agent, and 1 to 10 parts by weight of surfactant; (d) mixing 50 to 150 parts by weight of the foamed composition obtained in (c) at 100 parts by weight to 100 parts by weight of the polyurethane prepolymer obtained in (b) to prepare a foamed mixture; (e) The foam mixture obtained in (d) is supplied onto a release paper fixed to an inclined angle at a predetermined angle, and is foamed while flowing down the inclined surface to form a tack-like gel before curing to a thickness of 1 to 20 mm. Obtaining a polyurethane foam layer; (f) laminating the polyurethane foam layer obtained in (e) and the non-porous waterproof polyurethane film layer obtained in (a) and pressing a predetermined gap to control the thickness of the foam dressing material. Method for producing urethane foam dressing material. The method of manufacturing a polyurethane foam dressing material according to claim 1, wherein the release paper is fixed inclined at an angle of 30 degrees to 70 degrees. The method of manufacturing a polyurethane foam dressing material according to claim 1, wherein the polyurethane foam layer and the polyurethane film layer are laminated in the step (f), followed by hot air drying. The method of manufacturing a polyurethane foam dressing material according to claim 1, further comprising the step (f) of aging the polyurethane foam dressing material in a hot air dryer. The method of claim 1, wherein the foam composition further comprises 0.01 to 20 parts by weight of a drug. The method of claim 1, wherein the foam composition further comprises 0.01 to 20 parts by weight of an absorbent aid and a humectant. The method according to any one of claims 1 to 6, further comprising increasing the absorption rate of the foam layer by impregnating and drying the polyurethane foam layer with a humectant. The method according to claim 7, further comprising the step of treating the oxygen plasma after the impregnation and drying of the humectant. The method of claim 7, wherein the humectant is glycerin; Triacetin; Propylene glycol; Method for producing a polyurethane foam dressing material, characterized in that at least one selected from the group consisting of sorbitol and polyethylene glycol. The method according to any one of claims 1 to 6, further comprising the step of increasing the absorption rate of the foam layer by treating the polyurethane foam layer with oxygen plasma. The polyurethane according to any one of claims 1 to 6, wherein the polyol is an ethylene oxide / propylene oxide copolymer having two or more hydroxyl groups and having a molecular weight of 500 to 6,000 with an ethylene oxide content of 20% to 90%. Method for producing foam dressing material. The method of claim 1, wherein the isocyanate is isophorone diisocyanate; 2,4-toluene diisocyanate; 2,6-toluene diisocyanate; Method for producing a polyurethane foam dressing material, characterized in that at least one selected from the group consisting of methylene diphenyl isocyanate. The method of claim 1, wherein the diol compound is ethylene glycol; Propylene glycol; 1,3-butanediol; A method for producing a polyurethane foam dressing material, characterized in that at least one selected from the group consisting of 1,4-butanediol and 1,6-hexanediol. delete delete delete delete delete

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