KR101202875B1 - Hydrophilic polyurethane foam dressing containing mesh film and preparation method thereof - Google Patents

Abstract

PURPOSE: A hydrophilic polyurethane foam dressing and a preparation method thereof are provided to prevent the foam dressing from adhering to an injured part. CONSTITUTION: A hydrophilic polyurethane foam dressing comprises a waterproof polyurethane film layer(10), a foam layer(20) which is made of polyurethane foam and is formed under the polyurethane film layer, and a mesh film layer(30) which is formed under the foam layer. The foam layer comprises a plurality of open cells with 1-1000 micrometer diameter and a plurality of pores which penetrates the open cells. The polyurethane film layer is made of a moisture-permeable and waterproof film. The mesh film layer comprises a mesh film made of a polymeric material.

Description

Hydrophilic polyurethane foam dressing material containing a mesh film and a method for manufacturing the same

The present invention relates to a polyurethane foam dressing material that protects wounds such as wounds and burns and helps to heal wounds. In particular, the foam dressing agent adheres to the wound surface while mechanical properties of the foam dressing agent are reduced after absorption of exudates. A hydrophilic polyurethane foam dressing material and a method for producing the same are provided.

Wet dressing methods have been found to facilitate the healing of wounds to prevent the fluids secreted from the wound from being dehydrated or dried. 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 bacterial invasion from the outside, and should not stick to the wound surface during the exchange to damage 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, because gas and water vapor such as oxygen and carbon dioxide cannot pass, there is a disadvantage that excessive exudates accumulate, and there is a problem that 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 terminal 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 three-layered structure having 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.

One Biogen Co., Ltd., one of the applicants, is a non-porous polyurethane film layer that separates air and wounds, and a highly absorbent polyurethane foam inner absorbent layer and an inner absorbent layer having 1 to 600 µm open pores under the film layer. 1 to 50㎛ fine open pores are formed at the bottom to absorb the exudates, and the three-layer dressing material including the wound surface contact layer having the wound surface non-adhesive properties is disclosed in Patent 10-0745050 and 10-0937816. I have registered. 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 by using a comma coater, etc., and then wound in a roll to greatly improve productivity and processing efficiency in the manufacture of foam dressing materials. I was. The patented techniques of the present applicant have been able to increase the productivity significantly compared to the prior art, but the change in tack time due to frictional heat generated in the mixing head and the isocyanate content according to the time-lapse of the synthesized polyurethane prepolymer ( %) Due to the difference in productivity due to the decrease in mechanical properties of the final product due to the change, it was still insufficient for mass production. Therefore, the low productivity in the manufacture of hydrophilic foam dressing material is difficult to mass production remains a problem to be solved.

Such hydrophilic foam dressing materials are simpler to use than hydrogel, hydrohydrocolloid and non-woven dressings, have excellent exudative properties, and above all, are known to have non-stick surface properties compared to other conventional dressing materials. have. Thus, hydrophilic foam dressings are used very widely, from wounds with less exudate to wounds with large amounts of exudate. However, foam dressings with hydrophilic properties tend to have a sharp drop in mechanical properties after the exudate absorption, especially in the later stages of wound treatment where the amount of exudate decreases, and the foam dressing material adheres to the wound surface, causing tissue damage during exchange. There is a problem that causes another damage to remove the residue (debris) of the foam dressing material stuck to the. Thus, while the hydrophilic foam dressing agent has many advantages, it requires a careful attention of the user when changing the dressing, and there is also a very uncomfortable point of view of the patient. In order to solve this problem of the hydrophilic foam dressing agent, a method of adding a hydrophilicity imparting agent, a humectant or the like in the manufacture of a foam or adjusting the pore size of the hydrophilic foam dressing agent is used. Although this method alleviates the problem to some extent, it is not a complete solution. The mechanical properties of the foam dressing agent after the exudation absorbs and the adhesion of the foam dressing agent to the wound surface is still the biggest problem of the hydrophilic foam dressing agent. Remains.

In addition, when using the hydrophilic foam dressing material, only the portion that absorbs the exudate after absorbing the exudate is used to swell toward the wound surface, and the edges of the four sides are lifted outward based on the wound surface.

U.S. Patent 4,664,662 (July 1,1985) U.S. Patent 4,860,737 (1983.8.11) U.S. Patent 5,147,338 (1991.6.17) U.S. Patent 4,773,409 (September 20, 1985) U.S. Patent 4,773,408 (September 25, 1985) Republic of Korea Patent No. 0404140 Republic of Korea Patent No. 0553078 Republic of Korea Patent No. 0745050 Republic of Korea Patent No. 0937816

The present invention is to solve the conventional problems with the hydrophilic foam dressing material as described above. It is an object of the present invention to provide a hydrophilic polyurethane foam dressing material having a novel structure and a method of manufacturing the same, which eliminates the phenomenon that the foam dressing agent adheres to the wound surface while the mechanical properties of the foam dressing agent are reduced after the exudation is absorbed.

In addition, the present invention, a new hydrophilic poly solved the problem that the existing foam dressing material swells only the portion absorbing the exudate after the exudate absorbed to the wound surface and the edges of the four sides are lifted outward relative to the wound surface, the dressing is difficult to fix It is an object to provide a urethane foam dressing material.

It is also an object of the present invention to solve the low productivity problem of the hydrophilic polyurethane foam dressing material of the prior art, and to greatly improve productivity and processing efficiency by a simpler and more efficient new manufacturing process. In particular, as the storage time of the mixing head, such as heat (heating) of the mixing head and the longer the storage time of the synthesized polyurethane prepolymer, it is possible to produce a foam dressing material having a certain physical properties regardless of the isocyanate content falling, innovative workability The purpose is to improve.

Other objects and advantages of the present invention will be described below, and will become more apparent from the embodiments of the present invention.

In the present invention to achieve the above object,

Waterproof polyurethane film layer;

A foam layer made of polyurethane foam and formed under the polyurethane film layer;

A hydrophilic polyurethane foam dressing material is provided that includes a mesh film layer formed under the foam layer.

In the present invention,

(a) applying a polyurethane resin solution to a release paper and drying to obtain a non-porous waterproof polyurethane film layer;

(b) preparing a mesh film layer including a mesh film of a polymer material;

(c) preparing a polyurethane prepolymer by adding isocyanate to the polyol and reacting it;

(d) mixing 50 to 200 parts by weight of the foamed composition including 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, at 100 parts by weight of the polyurethane prepolymer obtained in (c). Preparing a foam mixture;

(e) the foam mixture obtained in (d) is fed onto the mesh film layer obtained in (b) and passed through the manglora with a certain gap before becoming a tacky gel. There is provided a method of producing a hydrophilic polyurethane foam dressing material comprising the step of forming a foam layer while controlling the thickness, and laminating the non-porous waterproof polyurethane film layer obtained in the above (a) on the foam layer.

Polyurethane foam dressing material of the present invention is a mesh film on the surface in contact with the wound, the mechanical properties of the foam dressing agent after the exudation absorbs can be solved, the problem that the foam dressing agent sticks to the wound surface, Accordingly, it is possible to reduce the cause of tissue damage as well as to reduce the trouble of fixing and changing the dressing.

According to the polyurethane foam dressing material manufacturing method of the present invention, a predetermined gap is discharged before the foamed mixed solution is discharged onto the mesh film layer and becomes a tacky gel state (flowable state). By passing through the manglora, while controlling the thickness of the foam dressing material at the same time it is possible to significantly improve the productivity and processing efficiency of the foam dressing material by a new manufacturing method of laminating a moisture-permeable waterproof polyurethane film layer thereon. In addition, it is possible to mass-produce foam dressing materials and greatly reduce production costs by not limiting mechanical properties due to changes in the isocyanate content with time-lapse of the synthesized polyurethane prepolymer and changing mechanical properties according to the variation of each lot of polyol. Foam dressings can be supplied at low cost.

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.

1A and 1B are schematic cross-sectional views of a polyurethane foam dressing material according to the present invention.
2a and 2b is an exemplary form of a mesh film according to the present invention, (a) is a mesh film, (b) is a nonwoven fabric.
3A is a photograph before absorption of exudates of Preparation Example 1, and FIGS. 3B and 3C are photographs after absorption of Preparation Example 1 (3c is a cross-sectional view).
4A is a photograph before absorption of exudate of Comparative Example 1, and FIGS. 4B and 4C are photographs after absorption of Comparative Example 1 (4c is a cross-sectional view).

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, the "moisture permeable film" refers to a polyurethane film manufactured to have moisture permeability compared to a general polyurethane film using a hydrophilic polylized polyurethane having a hydrophilic group introduced therein. 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.

Structure of polyurethane foam dressing material

The hydrophilic polyurethane foam dressing material including the mesh film of the present invention is a waterproof polyurethane film layer 10, a foam layer 20 formed below and a polyurethane foam, and a mesh formed below the foam layer. The film layer 30 is included. Hereinafter, with reference to the accompanying drawings will be described the structure of the polyurethane foam dressing material according to the present invention.

1A and 1B are schematic cross-sectional views of a polyurethane foam dressing material produced according to the present invention. FIG. 1A consists of a waterproof polyurethane outer film layer 10, a foam layer 20 formed below and made of a polyurethane foam, and a mesh film layer 30 formed below the foam layer 20. 1B is another embodiment of the polyurethane foam dressing material of the present invention, further including a nonwoven sheet 40 between the foam layer 20 and the mesh film 30. If necessary during the manufacturing process, the release paper 5 may be further attached to the polyurethane outer film layer 10 and the mesh film layer 30, which may be peeled off during the manufacturing process or use.

The outer polyurethane film layer 10 is a moisture-permeable waterproof film, and is manufactured to have both moisture-permeability and water resistance using a hydrophilic polyurethane into which a hydrophilic group is introduced as a raw material. Polyurethane film layer 10 preferably has a high moisture permeability of 400 ~ 3,000g / ㎡ / day (relative humidity 10 ~ 90%, 37 ℃, Desiccant Method), bacteria from the outside (Bacteria), fungi and the like It prevents the invasion of, prevents leakage of exudates, and creates a moist environment on the wound surface.

Foam layer 20 consists of a foam of hydrophilic polyurethane. The foam layer 20 preferably has a structure in which a plurality of open cells having a diameter of 1 to 1,000 μm are formed, and a plurality of pores penetrating the open pores are formed. The average diameter of the pores is preferably 1 to 500 µm. Foam layer 20 serves to absorb and store exudate from the wound. The foam layer 20 preferably can absorb and store 100 to 1,000% by weight and has a density in the range of 0.05 to 1 g / cm 3. If necessary, the foam layer may further include necessary drugs such as antibacterial agents and wound healing agents. In this case, it is preferable to include the drug in the foaming mixture forming the foam layer and to foam the drug more uniformly and stably.

The mesh film layer 30 is made of a mesh film made of a polymer material and is in direct contact with the wound surface. The material of the mesh film, preferably polyurethane, polyethylene, polyester, polypropolene, polystyrene, polyvinylchloride, polyvinyl alcohol, polyvinylpyrrolidone, polyethylene glycol, PLGA (Poly (lactide-co) copolymers, chitin, chitosan, starch, nylon, cellulose, polycaprolactone (PCL), polylactic acid (PLA), polyglycolic acid (PGA), polyhydroxyalkanoate (PHA) One kind or two or more kinds selected from the group consisting of natural or synthetic high molecular materials (including microorganism-producing high molecular materials) can be used.

2A to 2B are schematic views illustrating various forms of the mesh film layer 30. As shown in FIG. 2A, various types of mesh films, such as straight lines, diagonal lines, intersecting straight lines, circular shapes, and the like, as shown in FIG. 2B, may be used. 2A to 2B are exemplary forms of mesh films that can be used, and the scope of the mesh films usable in the present invention is not limited thereto. Any mesh film having a structure capable of absorbing exudates and preventing the release of fibrous lint can be used in the present invention.

The mesh film layer 30 can prevent additional tissue damage or damage to new tissues by preventing the foam layer 20 whose mechanical properties are degraded after absorbing exudates, so as not to stick to the wound surface, and greatly reduce the inconvenience of changing the dressing. have. In addition, the existing foam dressing material has a problem that it is difficult to fix the dressing material because only the portion that absorbed the exudate absorbs the exudate after the absorption of the exudate, the edges of the four sides are lifted outward based on the wound surface, the polyurethane dressing material of the present invention is wound The part directly touching the surface is made of a mesh film to solve this problem. The mesh film also serves to prevent the release of fibrous lint from the nonwoven to the wound surface when a nonwoven sheet is formed between the mesh film and the foam layer.

The polyurethane foam dressing material of the present invention may optionally further comprise a nonwoven fabric sheet 40 between the foam layer 20 and the mesh film 30 as needed (FIG. 1B). The non-woven fabric sheet 40 should be able to absorb the exudate to be delivered to the polyurethane foam layer. Also, fabrics in the form of woven fabrics may be used as long as they do not interfere with the absorption of exudate. At this time, the absorbent nonwoven fabric 40 is a viscose rayon (cotton), cotton (cotton), polyethylene terephthalate (PET), polypropylene (PP), nylon (Nylon), polyethylene (PE), cellulose-based synthetic and derived fibers (alginate , Carboxymethyl cellulose, and the like) and those prepared by mixing one or two or more kinds selected from various synthetic polymers can be used. In the present invention, "non-woven fabric" is meant to include fibers in the form of woven fabric as well as non-woven fabric (不 織布) type, and includes all of a variety of natural and synthetic polymer materials. The thickness of the nonwoven fabric sheet 40 is suitably in the range of 0.01 mm to 5 mm and a weight of 5 to 500 g / m 2. More preferably, the thickness is in the range of 1 mm to 3 mm and the weight is in the range of 30 to 500 g / m 2, most preferably in the range of 0.5 mm to 2 mm and the weight is in the range of 30 to 100 g / m 2.

Most preferably, the mesh film layer 30 is formed by laminating the mesh film 30 and the absorbent nonwoven fabric 40. The mesh film 30 and the absorbent nonwoven sheet 40 can be easily laminated by a known method such as thermocompression bonding, adhesion, or adhesion. In one embodiment of the present invention was laminated by the method by thermocompression bonding.

Method for producing a polyurethane foam dressing material according to the present invention comprises the steps of preparing a waterproof polyurethane film layer; Preparing a polyurethane prepolymer; Preparing a foam mixture; Preparing a mesh film layer; Supplying the foamed mixed solution on a mesh film layer to form a foam layer and laminating a waterproof polyurethane film layer. Hereinafter, each step will be described in detail.

Waterproof polyurethane Film layer  Produce

A hydrophilic polyurethane resin solution having a hydrophilic group introduced thereon is applied to a release paper and dried to form a non-porous waterproof polyurethane film layer. The polyurethane resin solution is preferably obtained by adding 20 to 70 parts by weight of methyl ethyl ketone and 5 to 30 parts by weight of dimethylformamide to 100 parts by weight of polyurethane resin. The bubble of the polyurethane resin solution thus obtained is removed, coated on a release paper, and dried to obtain a non-porous waterproof polyurethane film layer. In this case, 1 to 10 parts by weight of the pigment may be further added to the polyurethane resin solution (100 parts by weight of 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 using a coating gauge or the like and dried to obtain a non-porous polyurethane film layer. At this time, by using a polyurethane resin having both moisture permeability and water resistance as the polyurethane resin, that is, a polyurethane resin having a hydrophilic group introduced into the main chain, a moisture-permeable waterproof polyurethane film layer having both moisture permeability and water resistance can be obtained. The polyurethane film layer forms the outer side of the polyurethane dressing material of the present invention.

Polyurethane Prepolymer  Produce

Isocyanate is added to the polyol and reacted to prepare a polyurethane prepolymer. Specific preparation examples of the polyurethane prepolymer are as follows. First, the polyol is added and the temperature is raised to 50 ° C. while stirring at about 150 RPM and then stirred for 30 minutes. Then, an isocyanate is added to react the NCO content (%) until the theoretical value is reached under nitrogen atmosphere. . Preferably, the polyol includes a diol and an antioxidant.

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 in 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 a polyol is preferably used with 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; Any one or two or more of methylene diphenyl isocyanate are used together.

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. On the contrary, if it is too low, the foam mixture will be cut and penetrated into the nonwoven fabric. Preferably, the viscosity of the prepolymer synthesized by adding a 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. Antioxidant 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. Foaming composition is preferably 60 to 120 parts by weight of deionized water; 0.5-40 weight part of crosslinking agents; It includes 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 moisturizer 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 plays a role in controlling the pore and cell size and opening ratio of the pores in the polyurethane foam dressing material. In particular, BASF's F-68, which is an ethylene oxide / propylene oxide block copolymer, is known to be non-toxic and helps to clean wounds without causing injury to tissues, and therefore, may be most preferably used.

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. Thus, the term "humidant" is used in the sense to include a well-known moisturizer generally known as a moisturizer, as well as a wound healing aid that maintains a moist environment to inhibit 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 antimicrobial agents known to have a wound healing effect, as well as wound healing aids having 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.

Mesh Film layer  Preparation, preparation of foam mixture, Foamy  Formation and Lamination

First, the mesh film layer 30 is prepared. As for the mesh film layer 30, Preferably, the mesh film and the release paper are laminated | stacked, or the mesh film and the nonwoven fabric are laminated | stacked preferably. The release paper should be able to be peeled off during the manufacturing process, preferably using a silicone coated release paper. In addition, the description of the mesh film layer 30 is the same as above.

Then, 50 to 200 parts by weight of the foaming composition is stirred at 100 parts by weight at 100 parts by weight of the polyurethane prepolymer prepared in the above step, thereby forming a foamed mixture solution and supplying it onto the mesh film layer 30 to form a foam layer. At this time, if necessary in the manufacturing process, the polyurethane outer film layer 10 and the mesh film layer 30 may be further attached to the release paper 5 that can be peeled off during the manufacturing process or use. Dressing the foamed mixture solution while flowing, that is, while giving a certain gap before the gel state with a tack (gel) state and passing through the manglor with the polyurethane film layer 10 of the moisture-permeable waterproof layer Laminate while adjusting the thickness of the ash. In this case, the paper may be simply laminated with the polyurethane foam layer 20 and the polyurethane film layer 10 when a predetermined time elapses from room temperature to 200 ° C. in a laminated state without using an adhesive or an adhesive. Immediately after the foam mixture is completely foamed and the curing is completed, the polyurethane foam layer 20 and the polyurethane film layer 10 is naturally laminated. In this case, the closer to room temperature, the longer the polyurethane foam layer 20 and the polyurethane film layer 10 is laminated, it is not efficient in terms of productivity. Preferably it is 30-100 degreeC, Most preferably, 40-80 degreeC is the most suitable. In addition, the curing time of the foam layer 20 and the curing time of the polyurethane film layer 10 is laminated can be easily adjusted by those skilled in the art according to the process conditions. In addition, the lamination method of this invention is not limited to this, The well-known lamination method which uses an adhesive or an adhesive agent, or adds pressure can also be used.

In one embodiment of the present invention, the polyurethane prepolymer and the foaming composition are stirred at a high speed of about 3000 RPM, and then the foamed mixture is supplied onto the absorbent nonwoven fabric 40 on which the mesh film 30 is laminated and immediately tacked. Give a certain gap before the gel state (flowable state) and pass the manglor at the same time as the moisture-permeable waterproof layer polyurethane film layer 10, while laminating while controlling the thickness of the foam dressing material 5 minutes at 70 ℃ hot air dryer to prepare a foam dressing material.

[ Example ]

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 Synthetic example

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

Breathable  Polyurethane Synthetic example

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

Breathable  Polyurethane film Manufacturing 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 (5) (Hanil) 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 waterproof polyurethane on one side of the matte release paper (5). A film was formed. The thickness of the moisture-permeable waterproof polyurethane film produced in this manner was 20 μm.

Foam composition Manufacturing example

Next, a foaming composition was prepared under the same conditions as in Table 3.

Polyurethane foam Dressing material Manufacturing example (One)

(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 foaming composition manufacturing example by stirring at 3,000 RPM for 10 seconds, the mesh film 30 is laminated The absorbent nonwoven fabric 40 was fed on.

(2) The moisture-permeable water-resistant poly formed on the release paper (5) immediately before supplying the foam mixture in (1) above and before becoming a tack-like gel (flowing state). The absorbent nonwoven fabric 40 sheet layer on which the urethane film layer 10 and the mesh film 30 were laminated was simultaneously laminated while giving a gap of 5 mm and passing through mangloras.

(3) Polyurethane foam dressing material produced by curing the product of the process of (2) above laminated in a 70 ° C. hot air dryer for 5 minutes and then peeling off the release paper (5) on which the moisture-permeable waterproof polyurethane film was formed. The results of thickness, absorbency, rate of absorption, strain before and after exudation, and animal experiments are shown in Table 4 below.

Polyurethane foam Dressing material Manufacturing example (2)

(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 preparation example by stirring for 10 seconds at 3,000 RPM for a mesh film laminated the release paper (30 ) Was supplied.

(2) The moisture-permeable water-resistant poly formed on the release paper (5) immediately before supplying the foam mixture in (1) above and before becoming a tack-like gel (flowing state). The urethane film layer 10 and the release paper is laminated to the mesh film layer 30, while simultaneously giving a 5mm gap (gap) and the paper while passing through the manglo.

(3) Polyurethane foam dressing material produced by curing the product of the process of (2) above laminated in a 70 ° C. hot air dryer for 5 minutes and then peeling off the release paper (5) on which the moisture-permeable waterproof polyurethane film was formed. The results of thickness, absorbency, rate of absorption, strain before and after exudation, and animal experiments are shown in Table 4 below.

Comparative example  One

Commercially available product Viatein (Coloplasm) was used for the experiments in order to compare the properties. The thickness, absorbency, rate of absorption, strain before and after exudation of the foam dressing material, and the results of animal experiments are shown in Table 4 below.

Comparative example  2

In order to compare physical properties, a dressing material was manufactured according to Korean Patent No. 0937816. The thickness, absorbency, rate of absorption, strain before and after exudation of the foam dressing material, and the results of animal experiments are shown in Table 4 below.

Test Example

The physical properties of the polyurethane foam dressing material prepared in the above preparation example and the polyurethane foam dressing material of the comparative example were measured by the methods illustrated below, and the measured experimental results are shown in Table 4 below.

① Absorption rate (seconds)

After the dressing material was taken in a size of 3cm × 3cm and left at room temperature for 24 hours, a dropping time of 1ml of distilled water was dropped using a dropper at a height of about 2cm, and the time taken for the water droplets to be completely absorbed was measured.

② Absorbance (%)

The dressing material was taken in a size of 3 cm × 3 cm and left for 24 hours at room temperature, and then impregnated and stored in 37 ° C. distilled water for 24 hours to measure absorbance (%) using the initial dressing weight and the dressing weight difference after absorption. .

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 degree of deformation before and after absorption

The dressing material was taken in a size of 3 cm × 3 cm and left at room temperature for 24 hours, and then 5 ml of distilled water was dropped using a dropper at a height of about 2 cm, and then the degree of deformation of the dressing after completely absorbed was compared.

⑤ Animal experiment

Experiments were performed using 250-300 g rats at 6 to 8 weeks of age. Lett was anesthetized with rambutal. Intra-tracheal intubation and oxygen supply were allowed to spontaneously breathe indoor air. The flanks were cut and the hair was completely removed with an epilator. The surgical site was disinfected with povidone and alcohol, and aseptic surgery was performed. After making a skin defect of 80π㎜ on the back, wash the wound with physiological saline and wipe it with dry gauze, attach the dressing material about 1cm wider than the wound, cover 2 gauze on it and prevent the dressing from falling off. In order to fix the body lightly with an elastic bandage. The dressing was changed on the 5th, 10th, 15th, 20th, and 25th day after the dressing, and the polyurethane foam dressing material stuck to the wound surface as time passed, and the formation of foam residue and the phenomenon of lint detaching to the wound surface Observed.

As shown in Table 4, in the case of Preparation Example 1, the hydrophilic foam dressing material in which the mesh film 30 was laminated on the absorbent nonwoven fabric adhered to the wound surface as a result of animal experiments, and the residue of the foam dressing material remained on the wound surface. In the case of Preparation Example 2, as the new tissue grows between the fibrous tissues, it is found that the fibrous lint of the nonwoven fabric adheres to the wound surface at the time of exchange and the detachment is very severe. Can be. Therefore, the mesh film layer 30 is laminated, thereby eliminating such a problem, it can be confirmed that there is no problem in the functionality as a dressing material by absorbing the exudation smoothly. On the other hand, in the case of Comparative Example 1 and Comparative Example 2, the foam dressing material did not stick to the wound surface when the initial exudate was large, but after 20 days, the foam stuck to the wound surface and stuck to the wound surface in some cases. This was found.

In addition, when examining the degree of deformation of the dressing before and after the exudation absorption, the degree of deformation was negligible after absorption in Preparation Example 1 and Preparation Example 2, but in Comparative Example 1 and Comparative Example 2, the deformation occurred rapidly after absorption. there was. 3A is a photograph before absorption of the exudates of Preparation Example 1, and FIGS. 3B and 3C are photographs after absorption of Preparation Example 1. FIG. 4A is a photograph before absorption of exudate of Comparative Example 1, and FIGS. 4B and 4C are photographs after absorption of Comparative Example 1. FIG. In this way, the exudation area of the exudation is severely deformed, so that the absorption area protrudes toward the wound surface and the edges of the two sides are deformed on the opposite side, so that the dressing is not in close contact with the wound area and the dressing fixation may be difficult, which may be very inconvenient. .

Overall, Preparation Example 1 and Preparation Example 2 of the present invention were found to be inferior in terms of absorption rate, absorbency, and moisture permeability, which are functions to have as a dressing material, as compared with conventional foam dressing materials.

The specific parts of the present invention have been described in detail above, and those skilled in the art to which the present invention pertains are those specific technologies, which are merely preferred embodiments, and the scope of the present invention is not limited thereto. Therefore, the substantial scope of the present invention will be defined by the appended claims and equivalents thereof.

The hydrophilic polyurethane foam dressing material of the present invention has a very good degree of deformation after the exudation of the exudates compared to other products, and in particular, does not stick to the wound surface and leaves a residue of the foam dressing material. The polyurethane foam dressing material can be customized according to the conditions and conditions of the. Polyurethane foam dressing material according to the present invention can be widely used for medical use or non-medical use in a variety of fields that require such physical properties, such as medical dressing material, disposable diapers, women's goods (disposable sanitary napkin).

5: release paper 10: moisture-permeable waterproof film layer
20: hydrophilic polyurethane foam layer 30: mesh film layer
40: nonwoven fabric sheet P: pores
A: Shape that swells toward the wound surface after absorption

Claims (12)

Waterproof polyurethane film layer;
A foam layer made of polyurethane foam and formed under the polyurethane film layer;
Hydrophilic polyurethane foam dressing material comprising a mesh film layer formed under the foam layer. The hydrophilic polyurethane of claim 1, wherein the foam layer 20 comprises a plurality of open cells having a diameter of 1 to 1,000 μm and a plurality of pores penetrating the open pores. Foam dressings. According to claim 1, wherein the polyurethane film layer is made of a moisture-permeable waterproof film, hydrophilic characterized in that it has a moisture-permeability of 400 ~ 3,000 g / ㎡ / day (relative humidity 10 ~ 90%, 37 ℃, Desiccant Method) Polyurethane foam dressing. The hydrophilic polyurethane foam dressing material of claim 1, wherein the mesh film layer comprises a mesh film made of a polymer material. The hydrophilic polyurethane foam dressing material of claim 1, wherein the foam layer further comprises a drug. The hydrophilic polyurethane foam dressing material according to any one of claims 1 to 5, wherein the mesh film layer further comprises a nonwoven sheet between the foam layer. The hydrophilic polyurethane foam dressing material of Claim 6 whose thickness of the said nonwoven fabric sheet is 0.01 mm-5 mm. (a) applying a polyurethane resin solution to a release paper and drying to obtain a non-porous waterproof polyurethane film layer;
(b) preparing a mesh film layer including a mesh film of a polymer material;
(c) preparing a polyurethane prepolymer which is reacted by adding isocyanate to the polyol;
(d) mixing 50 to 200 parts by weight of the foamed composition including 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, at 100 parts by weight of the polyurethane prepolymer obtained in (c). Preparing a foam mixture;
(e) the foam mixture obtained in (d) is fed onto the mesh film layer obtained in (b) and passed through the manglora with a certain gap before becoming a tacky gel. Forming a foam layer while controlling the thickness thereof, and simultaneously laminating the non-porous waterproof polyurethane film layer obtained in the above (a) on the foam layer. 9. The method according to claim 8, wherein the mesh film layer comprises a release paper and a mesh film detachably bonded when used thereon, and the foam mixture is supplied onto the mesh film. The manufacturing method according to claim 8, wherein the mesh film layer includes an absorbent nonwoven fabric and a mesh film laminated thereon, and the foam mixture is supplied onto the absorbent nonwoven fabric. The method according to claim 8, wherein the foam composition further comprises 0.01 to 20 parts by weight of the drug. The method according to claim 8, further comprising the step of aging the laminated polyurethane foam dressing material in a hot air dryer following the step (e).

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