KR101933486B1 - Antibacterial polyurethane foam dressing and producing method thereof - Google Patents

Abstract

The present invention relates to an antimicrobial polyurethane foam comprising a breathable and waterproof polyurethane film layer, a microporous polyurethane foam layer and a perforated polyurethane film layer, wherein the perforated polyurethane film layer contains an antimicrobial drug Dressing material. The antimicrobial polyurethane foam dressing material of the present invention contains a drug in a perforated polyurethane film layer that directly contacts a wound site, thereby having a better adherence feeling and less dimensional change rate than conventional polyurethane foam dressing materials, It is easy to release and has a long duration so that it can continuously exhibit antibacterial activity.

Description

TECHNICAL FIELD The present invention relates to an antibacterial polyurethane foam dressing material and an antimicrobial polyurethane foam dressing material,

The present invention relates to a polyurethane foam dressing material having antimicrobial properties, and more particularly, to a polyurethane foam dressing material containing an antibacterial drug in a polyurethane film portion in contact with a wound surface.

Killing wounds has a long history as the foundation of medicine. A long time ago, animal oil, honey, and cotton were used for the treatment of wounds. However, as the history went on, many changes and developments were made in the techniques for treating wounds, and various kinds of wound dressing were developed.

Since the publication of a study in 1962 by a zoologist Winter that keeps wounds moist rather than keeping wounds dry, the usefulness of wounds in the wet environment continues to persist Has been proven and emphasized. A wet environment dressing method that prevents body fluids from being dehydrated or dried from the wound has been found to facilitate wound healing.

In the early 1970s, research has shown that the environment in which Rovee maintains a moist environment and does not form a crust moves the wound of epithelial cells and promotes epithelial regeneration. In the case of open wounds, the study shows that epithelial cell migration is suppressed by the collagen formed in the epithelial layer and that the wound fluid eliminates various growth factors that stimulate angiogenesis and epithelialization. .

Thus, the wet environment helps regenerative epithelial cells to develop smoothly along the wound surface, but in a dry environment it can not develop along the wound surface, so restoration of wound healing is delayed and wound healing becomes inefficient . In addition, since the materials involved in various wound healing contained in the exudate can smoothly play a role in a wet environment, wound healing proceeds efficiently.

Major factors involved in wound healing include humidity, temperature, infection, oxygen, and the like. Because the free movement of regenerating epithelial cells is impossible in a dry environment, a wet environment is indispensable for efficient wound healing. Cell proliferation and cell division are closely related to temperature because they are greatly disturbed at temperatures below 28 ° C. The ideal dressing must maintain a wet environment between the wound and the dressing, have adequate absorbency and moisture permeability, prevent drying of the wound surface, and avoid burning of the surrounding normal skin. In addition, it should have functionalities such as gas exchange and prevention of bacterial invasion from the outside, and it should not stick to the wound surface so as not to damage the new tissue during exchange.

The wet environment dressing materials generally used at present are classified into polyurethane foam, hydrocolloid, hydrogel, semi-permeable film dressing material and the like. Among them, polyurethane foam is excellent in the ability to absorb exudate, easy to exchange, cushioning, and has excellent protection against wounds and is mainly used for wounds in which a large amount of wounds or exudates are generated. However, even if the exudate absorbing ability is excellent and the wet environment composition is excellent, there is a problem that secondary infection may occur if it is applied to a wound that is infected or has a possibility of infection.

Infection has a direct effect on wound healing. In tissues containing a large number of bacteria, epithelial cell migration is not smooth, and healing is delayed if inflammation continues for a long time. It is also a side effect that can occur when the dressing is replaced or when treatment is not performed or when the contaminated area can not be sterilized completely.

To solve these problems, Korean Patent No. 10-1377569 discloses an antimicrobial wound dressing material and a method for producing the same, Korean Patent Laid-Open No. 10-2016-0035129 discloses a wound dressing composition for wound dressing of antimicrobial substances and a wound dressing material Discloses a process for producing the same. As described above, a dressing material which is developed in a conventional gauze dressing material and has excellent human binding property and excellent in wound treatment effect has been developed.

However, when the drug is contained in the dressing material, it is difficult to release the drug if the drug is not properly absorbed due to a large amount of exudate at the wound site. If the drug is injected for this purpose, Can be difficult. In addition, if the drug is released too quickly, the effect of the drug will disappear immediately, and the dressing can be replaced quickly.

Korean Patent Publication No. 10-2005-0073771 Korean Patent Publication No. 10-2007-0111758 Korean Patent Publication No. 10-2016-0035129 Korean Patent No. 10-0676937 Korean Patent No. 10-0859626 Korean Patent No. 10-1377569

It is an object of the present invention to provide a polyurethane foam dressing material containing an antimicrobial drug in a perforated polyurethane film layer in direct contact with a wound surface so that release of the drug can be rapidly and uniformly performed, .

In order to achieve the above object, in the present invention,

A three-porous polyurethane foam layer; A polyurethane film layer attached to the top surface of the foam layer and moisture permeable and waterproof; And a perforated polyurethane film layer attached to the underside of the foam layer and in contact with the wound surface,

Wherein the perforated polyurethane film layer is obtained by forming a film layer containing a drug by adding a drug to the composition for film formation and then punching the film layer to form an antimicrobial polyurethane foam dressing material.

In the dressing material, the perforated polyurethane film is preferably a hydrophilic polyurethane film. More preferably, the perforated polyurethane film layer has a thickness of 5 to 100 mu m.

In the dressing, the drug is selected from the group consisting of silver nitrate (AgNO ₃ ), sulfuric acid silver (Ag ₂ SO ₄ ), sentela asiatica, sodium fusidate, dexpantheol, ibuprofen, teatree oil ), SophoraAngustifolia Extract, Iris Extract, Glycyrrhiza Glabra Extract, Grapefruit Extract, Centella Asiatica Extract, Neem Extract, Locust Extract It is preferably selected from the group consisting of WitchHazel Extract, Portulace Oleracea Extract, Ponciri Fructus Extract, Aloe Extract, Sodium Fusidinate, Silver Sulfadiazine, Povidone, and Vaseline.

It is particularly preferred that the drug is silver nitrate (AgNO ₃ ).

Further, in the present invention,

Forming a microporous polyurethane foam layer,

Forming a moisture permeable, waterproof polyurethane film layer,

Forming a drug-containing film layer by containing a drug in the film-forming composition, and then perforating to form a perforated drug-containing polyurethane film layer; and

And laminating the formed polyurethane film layer, the polyurethane foam layer, and the perforated drug-containing polyurethane film layer in this order, followed by laminating the antibacterial polyurethane foam dressing material.

In the step of forming the perforated drug-containing polyurethane film layer, 0.05 to 0.5 part by weight of a drug is added to 5 to 30 parts by weight of dimethylformamide, and the mixture is stirred. Then, 100 parts by weight of a polyurethane resin and 20 to 70 parts by weight of methyl ethyl ketone Stirring the mixture, removing the bubbles, applying the composition to a release paper, and drying the mixture.

The polyurethane foam dressing material of the present invention is easy to release and uniform in drug release compared to the conventional polyurethane foam dressing material by containing an antimicrobial drug in the polyurethane film layer in which pores are uniformly in contact with the wound area and is perforated The longer the duration is, the more antimicrobial activity can be sustained. In addition, good adhesion and small dimensional change rate. In particular, the antibacterial dressing material of the present invention has a higher release ability than a polyurethane foam dressing material containing a conventional drug, and can exhibit a higher antimicrobial effect even when used in a small amount, and can reduce the amount of drug used, This is possible.

1 is a schematic cross-sectional view of a dressing material of the present invention.
2 is a photograph of a dressing material of the present invention, wherein FIG. 2A is a non-stick dressing material and FIG. 2B is a sticking dressing material.

The polyurethane foam dressing material of the present invention comprises a moisture permeable polyurethane film layer, a microporous polyurethane foam layer and a perforated polyurethane film layer, wherein the perforated polyurethane film layer contains an antimicrobial drug.

Hereinafter, the present invention will be described in more detail.

1. Polyurethane Foamed  Produce

(1) Polyurethane Prepolymer  Produce

Isocyanate is added to the mixed solution of polyol and diol to produce a polyurethane prepolymer. Specific preparation examples of the polyurethane prepolymer are as follows. First, a polyol and a diol were charged, and the mixture was heated to 50 ° C with stirring at a stirring speed of about 150 RPM. The mixture was stirred for 30 minutes. Isocyanate was then added to the reaction mixture until the NCO content (%) reached the theoretical value .

Examples of the polyol include polypropylene oxide glycol, polyethylene oxide glycol, polytetramethylene ether glycol, ethylene oxide / propylene oxide copolymer, polytetrahydrofuran / ethylene oxide copolymer, polytetrahydrofuran / propylene oxide copolymer, polybutylene At least one selected from the group consisting of a carbonate glycol, a polyhexamethylene carbonate glycol, a polycaprolactone glycol, a polyethylene adipate, a polybutylene adipate, a polyneopentyl adipate and a polyhexamethylene adipate are mixed and used.

The polyurethane prepolymer used for producing the polyurethane foam of the present invention is preferably a hydrophilic polyurethane prepolymer into which a hydrophilic group is introduced. The content of ethylene oxide, which is a hydrophilic group, is important for imparting hydrophilicity, which is disclosed in "Journal of Cellular Plastics 1976; 12; 285;" Journal of Cellular Plastics 1983; 19; 259 ", US Patent No. 4,008,189 Technology can be referred to. It is particularly preferable to use an ethylene oxide / propylene oxide copolymer having a molecular weight of 500 to 6,000 and a content of ethylene oxide of 20 to 90% by weight as a polyol having two or more hydroxyl groups.

Examples of the diol compounds include ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, triethylene glycol, diethylene glycol, tetraethylene glycol, Diethylene glycol, dipropylene glycol, dibutylene glycol, neopentyl glycol, 1,4-cyclohexanedimethanol, 2-methyl-1,3-pentanediol, etc. may be used singly or in combination of two or more. Preferably, one or more selected from ethylene glycol, propylene glycol and 1,4-butanediol are mixed and used.

As the isocyanate, aromatic, aliphatic and substituted isocyanates or mixtures thereof may be used. Examples of the isocyanate compound include 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, methylene diphenyl diisocyanate, 1,5-naphthalene diisocyanate, toluidine diisocyanate, hexamethylene- Diisocyanate, xylene diisocyanate, cyclohexylene-1,4-diisocyanate, lysine diisocyanate and tetramethylene-xylene diisocyanate are mixed and used. It is preferable to use isophorone diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate or methylenediphenyl isocyanate.

When preparing the polyurethane prepolymer, a known antioxidant may be added according to a known method. Examples of the antioxidant include antioxidants such as phenyl-beta-naphthalamine, cysteine hydrochloride, dibutylhydroxytoluene, nordihydroguar azoate, butylhydroxyanisole, phosphoric acid, citric acid, ascorbic acid, erosorbic acid, IRGANOX B1411, IRGANOX B1412, IRGANOX B1411, IRGANOX B141, IRGANOX B215, IRGANOX B220, IRGANOX B561, IRGANOX B513, IRGANOX B501W, IRGANOX B501W, IRGANOX B900, IRGANOX B900, IRGANOX B1411, IRGANOX B1412, PS800, IRGANOX PS802, and IRGAFOS P-EPQ. It is preferable to use one or more selected from phosphoric acid, citric acid, dibutylhydroxytoluene, butylhydroxyanisole, IRGANOX 1010, IRGANOX 1035, IRGANOX 1076 and IRGANOX 1330 in combination. The antioxidant is preferably added in the range of 0.05 to 5% by weight based on the total weight of the polyurethane prepolymer.

(2) Preparation of polyurethane foam composition

Water, a crosslinking agent, a surfactant and the like are mixed to prepare a foam composition to be used as a foaming agent. The foaming composition further comprises 60 to 120 parts by weight of deionized water, 0.5 to 40 parts by weight of a crosslinking agent, 1 to 10 parts by weight of a surfactant, 0.01 to 2 parts by weight of a pigment, 0.1 to 40 parts by weight of a moisturizing agent, .

As the crosslinking agent, glycerin, trimethylolpropane, 1,2,4-butanetriol and sorbitol may be used alone or in admixture of two or more. The crosslinking agent plays a role in improving the mechanical properties of the foam through the crosslinking reaction during the formation of the polyurethane foam.

As the surfactant, known surfactants can be used according to known uses and methods. For example, F-68, F-87, F-88, F-108 and F-127 of BASF Co., which are ethylene oxide / propylene oxide block copolymers, and L-580, L-603 and L- , L-5420, SZ-1703, L-6900, L-3150, Y-7931, L-1580, L-5340, L-5333, L-6701, L- Can be used. The surfactant serves to control the size of the pore of the polyurethane foam dressing material and the opening ratio of the pores. In particular, BASF's F-68, an ethylene oxide / propylene oxide block copolymer, is most preferred because it is known to be non-toxic, helping to clean the wound without injuring the tissue.

In the present invention, the moisturizing agent maintains a wet environment on the wound surface to inhibit the formation of a crust and smooth the wound healing. Thus, in the present specification, the term "moisturizing agent" is used to include a known moisturizing agent, which is generally known as a moisturizing agent, as well as a wound healing aid that maintains a moist environment and suppresses the formation of scarring and facilitates wound healing. Specific examples of the moisturizing agent include propylene glycol alginate, methylcellulose, carboxymethylcellulose sodium, carboxymethylcellulose calcium, carboxymethylstarch sodium, sodium alginate, ammonium alginate, potassium alginate, calcium alginate, sodium caseinate, guar gum, , Xanthan gum, cyclodextrin, gum arabic, gellan gum, carrageenan, karaya gum, casein, tara gum, tamarind gum, tragacanth gum, pectin, glucomannan, gatigam, arabinogalactan, L-aspartic acid, DL-alanine, L-isoleucine, lysine hydrochloride, glycine, glycerin, L-glutamine, L-glutamine, L-glutamine, Glutamic acid, sodium L-glutamate, pyridazine, L-threonine, sericin, serine, L-tyrosine, heparin, sodium chondroitin sulfate, Such as rhodium alginate, gelatin may be included in the foaming mixture within this range.

In addition, absorption enhancers such as a known super absorbent polymer may be included in the composition to increase the absorbency of the polyurethane foam.

In addition, a known additive known to be effective such as a stabilizer, a preservative, and a physical property regulator can be added in a small amount for a known purpose.

(3) Polyurethane Foamed  Produce

100 parts by weight of the polyurethane prepolymer and 70 to 90 parts by weight of the foam composition are mixed to prepare a foam mixture. The foamed mixed solution thus prepared is applied on the release paper in a thickness in the range of 0.05 to 10 mm to obtain a tackable gel-state polyurethane foam layer before curing. The polyurethane foam layer has microporosity when dried.

In the above step, the foamed mixed liquid which is stirred at a high speed is applied on a release paper with a constant thickness using a coating gauge or the like, and when a time of about 1 to 2 minutes passes, a polyurethane foam layer is formed in a tacky gel state. In this step, it is preferable that the polyurethane foam layer is formed in a state in which the foamed mixed solution applied on the release paper is cured before being cured, that is, in a tacky state like a gel, and the next step is carried out immediately.

The releasing paper is not particularly limited, but it is preferable to use a releasing paper treated with silicone.

The thickness of the polyurethane foam layer is not limited but is preferably in the range of 0.1 to 10 mm, particularly preferably in the range of 1.0 to 5.0 mm.

2. Breathable waterproof  Polyurethane Film layer  Produce

20 to 70 parts by weight of methyl ethyl ketone and 5 to 30 parts by weight of dimethylformamide were added to 100 parts by weight of a polyurethane resin, and the mixture was stirred. After removing the air bubbles, the mixture was applied to release paper and then dried to prepare a nonaqueous moisture permeable, waterproof polyurethane film layer do. If necessary, 1 to 10 parts by weight of a pigment may be further added to the polyurethane resin.

The bubble free polyurethane solution is coated on a matted release paper with a uniform thickness using a coating gauge or the like, followed by drying to obtain a nonporous polyurethane film layer.

As a polyurethane resin, a polyurethane resin having both moisture permeability and waterproofing property, that is, a polyurethane resin having a hydrophilic group introduced into the main chain, as in the case of the polyurethane resin used for forming the polyurethane foam layer, A waterproof polyurethane film layer can be obtained.

The moisture permeable, waterproof polyurethane film layer thus formed forms the outer side of the dressing material of the present invention.

The thickness of the moisture permeable, waterproof polyurethane film layer is preferably in the range of 10 to 30 mu m, particularly preferably in the range of 15 to 25 mu m.

3. Perforated polyurethane containing drug Film layer  Produce

0.05 to 0.5 part by weight of the drug is added to 5 to 30 parts by weight of dimethylformamide, and the mixture is stirred at 500 rpm for 10 minutes. Then, 100 parts by weight of a polyurethane resin and 20 to 70 parts by weight of methyl ethyl ketone are added and stirred. Then, the bubbles are removed and applied to release paper, followed by drying to obtain a polyurethane film layer.

At this time, when a hydrophilic polyurethane resin is used, a hydrophilic polyurethane film layer is obtained, and it is more preferable to use a hydrophilic polyurethane film layer.

Drugs include silver nitrate (AgNO ₃ ), sulfuric acid silver (Ag ₂ SO ₄ ), centella asiatica, sodium fusidate, dexpantheol, ibuprofen, teatree oil, Sophora Agustifolia Extract, Iris Extract, Glycyrrhiza Glabra Extract, Grapefruit Extract, Centella Asiatica Extract, Neem Extract, Witch Hazel Extract, It is preferably selected from the group consisting of Portulace Oleracea Extract, Ponciri Fructus Extract, Aloe Extract, Sodium Fusitinate, Silver Sulfadiazine, Povidone and Vaseline. It is particularly preferred to use silver nitrate, which is suitable for inclusion in the film, is easy to release the drug, and is suitable for maintaining antimicrobial activity during application of the dressing material.

The fabricated polyurethane film layer is prepared by preparing a perforation preparation step of preparing a fabric by attaching a protective vinyl to the bottom surface of the film and attaching a first release paper to an upper surface thereof and vertically pressing the fabric with a perforator equipped with a perforation pin A step of separating the protective vinyl from the fabric having the through-hole after the perforating step, a step of separating the protective vinyl from the fabric separated from the protective vinyl after the protective vinyl separating step, A first release paper separating step of separating the first release paper; And a second release paper lapping step of joining the second release paper to the bottom surface of the film after the first release paper separating step.

The thickness of the prepared hydrophilic film layer is preferably in the range of 5 to 100 mu m, more preferably in the range of 10 to 50 mu m, and particularly preferably in the range of 15 to 25 mu m.

The through hole may be formed in any one of a shape having a circular cross section or a polygonal cross section. By forming the through-holes in the film layer, it is possible to solve the problem that the film layer interferes with absorption of the exudation due to the foam layer, reduction of skin irritation on the wound surface, and the like. In the present invention, by forming the through-hole in the present invention, the drug contained in the drug is discharged smoothly through the cut surface to form the through-hole, thereby increasing the discharge power. do.

4. Lyo

The breathable and waterproof polyurethane film layer, the polyurethane foam layer, and the drug-containing perforated polyurethane film layer are laminated together. A polyurethane film layer is laminated on top of the polyurethane foam layer and a polyurethane film layer is formed on the bottom. The laminates can be top and bottom simultaneously or sequentially.

As the laminating method, a known laminating method such as a method using a pressure-sensitive adhesive or an adhesive, a method of applying a pressure, etc. can be used. It is more preferable that the polyurethane foam layer and the polyurethane foam layer which are in a gel state before being cured without using an adhesive or a pressure-sensitive adhesive are intact. At this time, the thickness of the polyurethane foam dressing material is adjusted by pressing with a certain gap.

The polyurethane film layer is lapped and dried to obtain a polyurethane foam dressing material.

Hereinafter, the present invention will be described in more detail with reference to specific examples. However, the following examples illustrate the present invention and the scope of the present invention is not limited to the following examples.

< Example  1>

(1) Preparation of a polyurethane foam layer

1,000 g of a polyurethane prepolymer was prepared using 861 g of ethylene oxide / propylene oxide polyol, 1 g of IRGANOX 1010 and 138 g of TDI (Toluene Diisocyanate). Ethylene oxide / propylene oxide polyol and IRGANOX 1010 were added to the reactor, heated to 50 캜 and stirred for 30 minutes. TDI was added to the reaction mixture. When the reaction started, when the temperature started to rise, the reaction was continued at 80 ° C. until the desired NCO% was reached. The viscosity (cps / at 26 캜) of the synthesized prepolymer emulsion was 8,130.

2,000 g of deionized water (DIW), 30 g of carboxymethylcellulose, 15 g of F-68 and 100 g of glycerin were mixed to prepare 2,145 g of a foamed composition.

The foamed mixture obtained by mixing the polyurethane prepolymer and the foamed composition was coated on a silicone release paper to obtain a tacky gel polyurethane foam layer before curing.

(2) Preparation of waterproofing polyurethane film layer

To 100 parts by weight of the moisture permeable waterproof polyurethane resin, 50 parts by weight of methyl ethyl ketone, 15 parts by weight of dimethylformamide and 5 parts by weight of pigment were mixed and stirred to prepare a polyurethane mixed solution.

The prepared polyurethane mixed solution was applied to a matted release paper (Yulchon Chemical Company) to which a polypropylene film was laminated to a predetermined thickness using a thickness gauge, and then dried in a hot air drier at 100 ° C for 30 minutes to form a moisture- To form a urethane film.

(3) Preparation of drug-containing perforated hydrophilic polyurethane film layer

0.2 part by weight of silver nitrate (AgNO ₃ ) was added as a drug to 20 parts by weight of dimethylformamide, and the mixture was stirred at 500 rpm for 10 minutes. 100 parts by weight of a hydrophilic polyurethane resin and 20 parts by weight of methyl ethyl ketone were added and stirred. Then, the bubbles were removed, and the resulting mixture was applied to a release paper and dried to prepare a hydrophilic polyurethane film layer.

Protective vinyl was attached to the bottom of the fabricated polyurethane film layer, a first release paper was attached to the upper surface, and the fabric was vertically pressed with a perforator equipped with a perforation pin to form a through hole. After the perforation was punctured, the protective vinyl was separated, and the first release paper was separated and the second release paper was laminated on the bottom surface of the film.

(4) The moisture permeable, waterproof polyurethane film layer, the polyurethane foam layer and the drug-containing hydrophilic perforated film layer were laminated together. A polyurethane film layer and a hydrophilic perforated film layer were laminated on the gel polyurethane foam layer before curing and on the lower side to prepare a dressing material.

The thickness of the breathable and waterproof polyurethane film layer was 20 占 퐉, the thickness of the polyurethane foam layer was 5.0 mm, and the thickness of the hydrophilic apertured film layer was 20 占 퐉.

1 is a schematic view showing a cross section of a dressing material manufactured in FIG. 1, wherein a release paper is bonded to a lower portion of the hydrophilic perforation film layer.

< Example  2>

20 parts by weight of dimethylformamide, 50 parts by weight of methyl ethyl ketone and 0.2 part by weight of silver nitrate as a drug were added to 100 parts by weight of the polyurethane resin as a drug-containing layer, and the mixture was stirred and then bubbles were removed and applied to release paper, A dressing material was prepared in the same manner as in Example 1 except that a perforated polyurethane film layer containing a drug was prepared and used.

&Lt; Comparative Example 1 &

(1) 2,000 g of deionized water, 30 g of carboxymethylcellulose, 15 g of F-68, 100 g of glycerin and 1 g of silver nitrate were mixed to prepare a foamed composition containing the drug.

(2) 100 parts by weight of the polyurethane prepolymer prepared in Example 1 and 80 parts by weight of the foamed composition containing the drug were stirred at 3,000 rpm for 10 seconds, and then supplied onto the OPP release paper.

(3) When the foam layer was not completely cured and had a constant thickness in a gel state in which it was tacky, the moisture permeable and waterproof film prepared in Example 1 was laminated on the top of the foam layer with a certain gap. Followed by drying in a hot air dryer at 100 占 폚 for 3 minutes. The polyurethane foam dressing material containing the drug in the foam composition thus prepared had a thickness of the moisture permeable waterproof outer film layer of 20 mu m and a thickness of the foam layer of 5.0 mm.

&Lt; Comparative Example 2 &

(1) 1,000 g of deionized water, 20 g of carboxymethylcellulose, and 0.5 g of silver nitrate were mixed to prepare a coating liquid containing the drug.

(2) 100 parts by weight of the polyurethane prepolymer prepared in Example 1 and 80 parts by weight of the foamed composition were stirred at 3,000 rpm for 10 seconds, and then supplied to the OPP release paper.

(3) When the foam layer was not completely cured and had a constant thickness in a gel state in which it was tacky, the moisture permeable and waterproof film prepared in Example 1 was laminated on the top of the foam layer with a certain gap. Followed by drying in a hot air dryer at 100 占 폚 for 3 minutes. The coating liquid containing the drug was applied to the wound contact surface on the polyurethane foam thus prepared. The thickness of the moisture permeable and waterproof outer film layer of the polyurethane foam dressing material coated with the drug thus obtained was 20 mu m and the thickness of the foam layer was 5.0 mm.

< Experimental Example  1>

Property measurement

The properties of the samples of Example 1, Example 2, Comparative Example 1 and Comparative Example 2 were measured as follows.

① Mechanical properties ( The tensile strength , Elongation rate )

Using a universal test machine (Instron), the load cell 50N, the width of the specimen 12 mm, the length of the specimen 100 mm, the crosshead speed 100 mm / min. The mechanical properties of each sample were measured. The test was terminated when the foam broke apart from the film.

② Exudation Absorption (%)

The specimens were taken at a size of 5 cm × 5 cm and allowed to stand at room temperature for 24 hours. The initial weight (A) was measured, and the samples were immersed in distilled water for 24 hours at a constant temperature of 24 to 26 ° C. and a relative humidity of 40 to 50% After removing the water from the surface, the weight (B) was measured. And finally calculated using the following equation.

Absorption (%) = (B-A) / A x 100

③ Retention of exudate (%)

The samples were placed in a size of 5 cm × 5 cm and allowed to stand at room temperature for 24 hours. The initial weight (A) was measured, and the samples were immersed in distilled water for 24 hours at a constant temperature of 24 to 26 ° C. and a relative humidity of 40 to 50% . After the storage, the surface water was wiped off, spread on a glass plate, and stored for 2 hours in a thermostatic hygrostat at a constant temperature of 36 to 38 ° C and a relative humidity of 40 to 50%, and then the weight (B) was measured. And finally calculated using the following equation.

Retention (%) = (B-A) / A x 100

④ Moisture permeability

The moisture permeability of the samples was measured using a thermo-hygrostat according to EN 13726-1. The temperature of the thermo-hygrostat was 37 ° C and the relative humidity was 20%.

The physical properties of the samples thus measured are shown in Table 1 below.

division Mechanical properties Absorption degree
(%) Retention
(%) Moisture permeability ^*
(g / m ² / day) Curl ^** Tensile strength (kgf / mm ₂ ) Elongation (%) Example 1 0.720 428 980 52 1,420 X Example 2 0.770 454 1,090 54 953 X Comparative Example 1 0.635 431 853 41 1,503 O Comparative Example 2 0.642 429 855 42 1,318 O *: Condition = 37 &lt; 0 &gt; C, 20% (EN-13726-2)
**: O = curl phenomenon, X = curl phenomenon

As can be seen from the results of Table 1, the tensile strength, the absorbency and the retention of the examples were superior to those of the comparative examples. This is the result of the breathable and waterproof perforated film on the wound interface of the polyurethane foam layer.

With respect to the moisture permeability, it can be seen that the moisture permeability of Example 1 is higher than that of Example 2, since the moisture permeability of the film having higher hydrophilicity is higher.

 Also, in the comparative examples, the phenomenon of curling the foam (Curl phenomenon) was observed, while the curling phenomenon of the foam did not appear in the examples.

< Experimental Example  2>

drug Emissivity  Confirm

The drug release performance of the above Example 1, Example 2, Comparative Example 1 and Comparative Example 2 was measured as follows, and the results are shown in the following table.

The maximum wavelength range was set based on the drug content. After the drug content was prepared by concentration, the absorbance was measured using a UV spectrometer, and a quantitative curve was drawn. Absorbance was measured by UV after elution with 20 cm 2 / ml of drug-containing perforated film at 37 ° C for 24 hours, 48 hours, 72 hours, 96 hours, 120 hours and 144 hours. The experimental results of the drug-releasing ability are shown in Table 2.

sample 0h 6h 12h 24h 48h 72h 96h 120h Example 1 1.401 2.188 2.320 2.421 3.844 4.069 4.097 4.085 Example 2 1.073 1.654 1.832 1.923 2.531 2.342 2.478 2.432 Comparative Example 1 0.490 2.098 2.321 2.324 3.830 3.623 3.759 3.657 Comparative Example 2 1.302 2.225 2.432 2.486 3.952 4.321 4.370 4.329

As can be seen from the results shown in Table 2, the drug release performance of the hydrophilic polyurethane film of Example 1 was the highest measured by the maximum drug releasing ability. In particular, the hydrophilicity of the polyurethane film of Example 1 was higher than that of the general polyurethane film of Example 2 It can be seen that when a polyurethane film having hydrophilic property is used, the emissivity is excellent. The polyurethane foam dressing material coated with the polyurethane foam of Comparative Example 2 had higher drug release ability than the other samples, but skin irritation due to rapid release may be exhibited. In the case of the polyurethane foam dressing material containing the drug in the foam composition of Comparative Example 1, the drug releasing ability was lower than that of the polyurethane foam dressing material in which the hydrophilic polyurethane film of Example 1 was laminated.

< Experimental Example  3>

Animal experiment

8-week-old SD rats were purchased, and general symptoms were observed while being purified for 1 week, and healthy animals were used for the experiment. Each animal was wounded with a certain size, and the same number of microbes were injected, and then the samples were used to confirm the antimicrobial activity and wound healing rate. 3 days, 7 days, and 10 days after injury. Photographs of differentiated wound sizes and changes are shown in Table 3 below.

It can be seen that Example 1 prepared using the hydrophilic moisture permeable waterproof polyurethane film containing the drug has the best restorative ability on the 3 days, 7 days and 10 days difference. It can be seen that the use of the polyurethane film is more effective for the wound than the injection of the drug into the foam-forming liquid as in Comparative Example 1. [

Table 3 shows the results of measuring the wound healing rate in Table 3 and numerically confirming the wound healing rate.

Primary Example 1 Example 2 Comparative Example 1 Comparative Example 2 0 100% 100% 100% 100% 3 56% 61% 50% 59% 7 33% 40% 32% 54% 10 12% 12% 26% 18%

From the results of Table 4, it can be seen that the recovery rate is the highest in Example 1 in which the drug is added to the hydrophilic polyurethane film.

<Experimental Example 4>

Antibacterial test

E. coli (Gram negative) was used as a test strain to confirm the antimicrobial activity of the samples. After the culture of the test strain, it was adjusted to 1.5 to 3.0 × 10 ⁵ CFU / mL and used as the test strain. Samples were added to the test solution and incubated for 1 h and 24 h with shaking, diluted, and dispensed in 1 mL each into a Perti dish. After 24 hours of incubation, viable cell counts were observed. The control group was shake-cultured without a sample. The results of the antibacterial test are shown in Table 5, and the photographs of the results are shown in Table 6.

(Unit: CFU / mL) division Early Control group
(After 1 hour) Control group
(After 24 hours) Test group
(After 1 hour) Test group
(After 24 hours) Example 1

1.8 X 10 ⁵

2.0 X 10 ⁵

2.8 X 10 ⁵ <30
(99.9% or more) <30
(99.9% or more) Example 2 <30
(99.9% or more) <30
(99.9% or more) Comparative Example 1 <30
(99.9% or more) <30
(99.9% or more)  Comparative Example 2 <30
(99.9% or more) <30
(99.9% or more)

As a result of checking the antibacterial properties of the samples in the above Examples and Comparative Examples, it was confirmed that the antibacterial properties were obtained.

10: breathable and waterproof polyurethane film layer
20: microporous polyurethane foam layer
30: drug-containing perforated polyurethane film layer
40: release paper

Claims (10)

A microporous polyurethane foam layer; A polyurethane film layer attached to the top surface of the foam layer and moisture permeable and waterproof; And a perforated drug-containing polyurethane film layer adhered to the underside of the foam layer and in contact with the wound surface,
Wherein the perforated drug-containing polyurethane film layer is formed by forming a film layer containing a drug by mixing a composition for forming a polyurethane film and silver nitrate (AgNO ₃ ) as an antibacterial drug, and then drilling to form a through hole , Antibacterial polyurethane foam dressing material. The method according to claim 1,
Wherein the perforated drug-containing polyurethane film layer is made of a hydrophilic polyurethane film. 3. The method according to claim 1 or 2,
Wherein the perforated drug-containing polyurethane film layer has a thickness of 5 to 100 占 퐉. delete delete Forming a microporous polyurethane foam layer;
Forming a breathable and waterproof polyurethane film layer;
Forming a perforated drug-containing polyurethane film layer; And
Laminating the formed polyurethane film layer, the polyurethane foam layer, and the perforated drug-containing polyurethane film layer in this order,
Wherein forming the perforated drug-containing polyurethane film layer comprises:
0.05 to 0.5 parts by weight of silver nitrate (AgNO ₃ ) is added to 5 to 30 parts by weight of dimethylformamide and stirred,
100 parts by weight of a polyurethane resin and 20 to 70 parts by weight of methyl ethyl ketone are added to a mixture of dimethylformamide and silver nitrate (AgNO ₃ ), followed by stirring. Thereafter,
Applying the bubbled mixture to a release paper and drying to obtain a drug-containing polyurethane film layer, and
Wherein the film layer is vertically perforated to form a through-hole to obtain a perforated drug-containing polyurethane film layer. &Lt; Desc / Clms Page number 20 &gt; delete The method according to claim 6,
Wherein the perforated drug-containing polyurethane film layer has a thickness of 5 to 100 mu m. A method for producing an antibacterial polyurethane foam dressing material.

delete delete

Images