JPH05337151A - Wound cover material - Google Patents

Abstract

PURPOSE:To achieve a promotion of healing a wound by a method wherein a hydrophilic porous film is laminated on a support layer comprising an unwoven cloth of carboxymethyl cellulose covered with a water-repellent material through an adhesive layer and a through hole with a specified diameter is formed on this laminate structural body. CONSTITUTION:This wound cover material covers an affected part from which a cover tissue is lost because of hot water or the like temporarily or permanently to prevent bacterial infection and the spillage of a body liquor while promoting repairing of the tissue and comprises a film layer made of a material tending to form a high-hydrate gel. It has a support layer comprising an unwoven cloth made of carboxymethyl cellulose covered with a water-repellent material. The wound cover material also has an adhesive layer and a hydrophilic porous film and is made up of a film of a laminate structural body in which these layers are laminated. The film is provided with a through hole with a diameter of 1-3mm. Antibacterial zeolite is contained at least in one of the support layer and the adhesive layer while the support layer is covered with collagen.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a wound dressing.

[0002]

2. Description of the Related Art A wound coating temporarily applied to an affected area for the purpose of protecting the affected area due to a disease or a wound such as a burn, a skin-extracting wound and a skin-exfoliating wound, and a traumatic skin defect wound, and promoting healing. Conventionally, gauze, absorbent cotton, etc. have been used as materials, but these have low bacterial infection prevention, and when the wound surface is dry to absorb exudate quickly, it causes pain, bleeding, etc. when removed. Accompanied.

Further, an ointment or the like is also used in combination, but in this case, on the contrary, the absorption of the exudate is insufficient and the wound surface becomes excessively wet.

As an alternative to these, particularly when applied to a wide range of wound surfaces, artificial synthetic resin sheets such as silicone gauze, silicone rubber and nylon and teflon having a velor-like surface structure are used. A coating film of a material and a coating film of a bio-derived material such as freeze-dried pig skin, chitin nonwoven fabric, collagen film, polyamino acid sponge, mucopolysaccharide complex collagen film are also known.

However, among these, the coating film of the artificial material leaves various problems in terms of adhesion to the affected area, water vapor permeability, cracking, etc., while the coating film of the biological material is biocompatible. However, many of them have antigenicity, and also have drawbacks such as bacterial infection and deterioration due to exudate, and there is a problem that the material is difficult to obtain.

More recently, a composite membrane consisting of a collagen-treated nylon mesh and a silicone membrane has been developed and put into practical use. Although it adheres well and has an appropriate water permeability, it adheres to the wound surface and the granulation tissue is covered. There was a drawback that it penetrated into the covering film. In addition, when applied to a wound surface where a large amount of exudate is produced, the exudate may accumulate in the nylon mesh under the silicone film and become infected, so recently treatments such as intentionally making holes in the silicone film have become necessary. Has been done.

[0007]

Autologous transplantation is currently the best method for treating the affected area when skin tissue is lost due to burns or the like, but it is very difficult when the skin defect area is wide. Therefore, even if it is applicable, it is necessary to repeat transplantation repeatedly over a long period of time. Therefore, instead of autologous transplantation, the affected area is temporarily or permanently covered to prevent bacterial infection and body fluid outflow,
Moreover, the development of a wound dressing that promotes tissue repair is desired.

[0008]

The above object can be achieved by the wound dressing of the present invention having the following constitution. (1) A support layer made of a carboxymethyl cellulose nonwoven fabric coated with a water-repellent material, an adhesive layer, and a membrane in which a hydrophilic porous membrane is laminated, and the through-membrane having a diameter of 1 to 3 mm is further formed in the laminated membrane. A wound dressing characterized by being provided. (2) The wound dressing material according to (1), wherein at least one of the support layer and the adhesive layer contains antibacterial zeolite. (3) The wound dressing material according to (1) or (2), wherein the support layer is coated with collagen.

As described above, the wound dressing of the present invention comprises a support layer of a carboxymethyl cellulose nonwoven fabric comprising a highly hydrous gel-forming substance membrane layer, an adhesive layer and a hydrophilic porous membrane layer.
Consists of layers.

The support layer of the water-repellent carboxymethylcellulose nonwoven fabric formed of the thin film of a highly hydrous gel-forming substance has a water-retaining property and a water-absorbing property, so that it has an appropriate storage function for exudate and a good function on the wound surface. It has adhesiveness and non-adhesiveness, and has a pain-suppressing action due to this property and the inactive property of the above-mentioned material on the living body. Therefore, an appropriate biological environment due to the high water content state is maintained, healing, especially epidermal regeneration is promoted, and further, good adhesion to the wound surface is provided, thereby suppressing the invasion of bacteria to the wound surface.

The water-repellent material is preferably selected from the group consisting of silicone, polyurethane, styrene-butadiene-styrene block copolymer and polytetrafluoroethylene.

The porous membrane may be a polyolefin such as polyethylene or polypropylene, or polyvinylidene fluoride,
It is formed of polyvinylidene chloride, a halogenated polyolefin such as chlorinated polyethylene, or a mixture thereof.

The hydrophilic porous membrane is not particularly limited as long as it is a polymer that coats the surface of the porous membrane by chemical bonding, but preferred examples include polymethoxyethyl acrylate, polydimethylacrylamide and methoxyacrylic acid ester. Examples thereof include polymers and dimethylacrylamide copolymers. The porous membrane has a pore size of 0.01 to 1.0 μm and a water vapor transmission rate (JIS standard) of 500 to 5000 g / m ² 2.
It is preferably 4 hr.

The wound dressing of the present invention has a diameter of 1 to 3 mm.
By providing a through hole having a diameter, the substance can be easily permeated, and particularly when the exudate is excessively stored, drainage of the exudate can prevent the formation of a hematoma or the like.

The present invention particularly relates to external infections,
It is preferable that the antibacterial zeolite is contained in either the adhesive layer or the support layer.

The zeolite, which is the matrix of the antibacterial zeolite used in the present invention, is an alkali or alkaline earth metal aminosilicate having a three-dimensionally developed skeleton structure.

The general formula is XM _a · O · Al ₂ O ₃ · y
Represented by SiO ₂ · zH ₂ O (M = metal ion, X = coefficient of metal oxide, a = 2Xn ⁻¹ (n = valence of metal),
y = coefficient of silica, z = molecular weight of bound water).

The antibacterial zeolite used in the present invention is an antibacterial metal ion-containing zeolite in which the cation exchange ability of zeolite is utilized and antibacterial metal ions are retained in the zeolite matrix. Antibacterial metal ions include silver, copper,
There is zinc, and when it is used as a surgical dressing, it is preferable to use silver, but it is more preferable to use a plurality of metals including zinc and copper.

The compound of the zeolite matrix and the antibacterial metal (copper, zinc) is approved as a food additive by the US Food and Drug Administration (FDA). Further, since the antibacterial metal ion is retained in the zeolite matrix, the minute amount of the antibacterial metal ion eluted can be gradually released for a long time by diffusion.

Furthermore, the wound dressing of the present invention facilitates hemostasis on the wound surface by coating the support layer with collagen.

The raw material used in the present invention is preferably collagen, acid- or alkali-treated collagen, which is further digested to remove the telopeptide at the molecular end thereof with proctase or pepsin to eliminate the antigenicity. Furthermore, in order to promote the hemostatic effect, the collagen used in the present invention is neutralized at a temperature of 37 ° C. with a phosphate-based buffer solution to form a periodic fibrous structure with a periodicity like in vivo. It is preferably in the form of reconstituted fibrotic collagen.

As the adhesive used in the present invention, a polyurethane-based adhesive is preferable because it is required to have good adhesiveness between the carboxymethyl cellulose nonwoven fabric and the hydrophilic porous membrane and to have water vapor permeability.

The wound dressing of the present invention is manufactured, for example, as follows. First, a predetermined amount of liquid paraffin and a crystal nucleating agent are added to polypropylene powder, melt-kneaded and pelletized. Melt the pellets at 150-200 ° C.,
Extruded by an extruder with T-die, cooled and fixed to form a film, liquid paraffin in the film is extracted, and heat-treated in air at about 135 ° C. for about 2 minutes,
A polypropylene porous film is obtained. Plasma-initiated surface graft polymerization of methoxyethyl acrylate onto the film,
A hydrophilic polypropylene porous membrane is obtained.

In producing the wound dressing, first, a carboxymethyl cellulose nonwoven fabric, which is a biocompatible, highly hydrous gel-forming substance, is prepared. After coating the above-mentioned base material with fibrotic atelocollagen and drying, a water-repellent substance,
For example, a water-repellent substance solution in which silicone, polyurethane, styrene-butadiene-styrene block copolymer, polytetrafluoroethylene is dissolved in hexane, tetrahydrofuran, or methyl ethyl ketone at about 1 to 10% by weight to prepare a highly hydrous gel-forming substance, It can be obtained by dipping a thin film of a highly hydrous gel-forming substance in this solution, or by applying it with a spray, a roller or the like. Next, a polyurethane adhesive solution is spread on Teflon to form a film, and in a state where the adhesive layer is still tacky, the water-repellent treated collagen-coated carboxymethylcellulose nonwoven fabric obtained in the above step is obtained. The adhesive layer is placed so that the upper surface adheres to the adhesive layer, dried, and optionally subjected to heat treatment for about 30 minutes and cured to adhere the adhesive layer to the upper surface of the support layer.

Finally, a desired wound dressing can be obtained by laminating a hydrophilic membrane made of polypropylene on a support layer having a high water content gel forming property to which an adhesive layer is attached.

[0026]

【Example】

(Example 1) Preparation of hydrophilic porous membrane (1) Polypropylene mixture having a melt flow index of 30 and 0.3 (mixture (mixing weight ratio 100: 40) 10
Biaxial extrusion of 0,400 parts by weight of liquid paraffin (average molecular weight 324) and 0.3 parts by weight of 1,3,2,4-bis (p-ethylbenzylidene) sorbitol as a crystal nucleating agent. It was melt-kneaded by a machine and pelletized. The pellets were mixed with the above twin-screw extruder for 150
It was melted at ~ 200 ° C and extruded into air from a T-die having a slit of 0.6 mm to form a film, and this film-like material was introduced into a cooling-immobilizing liquid by a guide roller placed below the T-die value and cooled and immobilized. After winding. This wound film-like material is cut into a certain size, fixed in both length and width, 1,1,
Liquid paraffin is extracted from the film-like material by immersing it in 2-trichloro-1,2,2-trifluoroethane for a total of four times for 10 minutes. A polypropylene porous film having a pore size of 0.6 μm and a film thickness of 140 μm was obtained.

Plasma-initiated surface graft polymerization of methoxyethyl acrylate was performed on this film to obtain a hydrophilically treated porous film. That is, the PP film was irradiated with argon plasma at 0.1 Torr for 15 seconds, and then graft polymerization was performed for 30 minutes in a methoxyethyl acrylate atmosphere (25 ° C., 4 Torr).

(Example 2) Preparation of hydrophilic porous membrane (2) Polyvinylidene fluoride powder (manufactured by Mitsubishi Petrochemical Co., Ltd.) Kyn
ar K301 (18 parts by weight) dissolved in acetone (73.8 parts by weight) and dimethylformamide (8.2 parts by weight) was cast on a polyethylene terephthalate film, and the solution was added to a 1,1,2-trichlorofluoroethane bath to give 5 parts. Dipping for a minute, average pore size 0.45μm, film thickness 135μ
m of polyvinylidene fluoride porous film was obtained.

A plasma-initiated surface graft polymerization of methoxyethyl acrylate was performed on this membrane to obtain a hydrophilically treated porous membrane.

Example 3 Preparation of Wound Dressing (1) A commercially available non-woven fabric of carboxymethyl cellulose sodium salt (manufactured by Tokai Senko Co., Ltd., etherification degree: 0.40) was used.
% Medical grade silastics-silicone (adhesive silicone type A, Dow Corning Co., Ltd.)
It was dipped in a hexane solution (made by Mitsui Chemical Co., Ltd.) for 10 seconds and then dried in a clean bench. Next, a 60% polyurethane adhesive (Heimren Y-199 (E), manufactured by Dainichiseika Co., Ltd.) was applied on a release paper using a precision coating tool (applicator) to form a film, and immediately after the application, The above nonwoven fabric was placed on the wet layer, left at room temperature for 10 minutes, and then cured in an oven at 80 ° C. for at least 1 hour. Further, the wound-dressing material could be obtained by backing and drying the hydrophilic polypropylene-made porous membrane obtained above and punching it with a 1 mm diameter punch at regular intervals.

Example 4 Wound Dressing Material (2) A non-woven fabric made of carboxymethyl cellulose sodium salt treated with silicone is prepared in the same manner as above. Next, a viscous solution in which an antibacterial zeolite (Ag, Zn zeolite, manufactured by Nichimen Co., Ltd.) was dispersed on a release paper made of 60% polyurethane was applied using an applicator to form a film, and immediately after the application, Place the above non-woven fabric on the wetting layer, leave it at room temperature for 10 minutes, and then at least 1 hour at 80 ° C.
Cured in oven for hours. The amount of Ag and Zn zeolite contained was about 0.69 mg / cm ² of non-woven fabric. Furthermore, wound-covering is performed by lining the hydrophilically-treated polypropylene porous membrane (or hydrophilically-treated polyvinylidene fluoride porous membrane) obtained above and punching the punches with a diameter of 1 mm at regular intervals. I was able to obtain wood.

Example 5 Wound Dressing Material (3) Atelocollagen (manufactured by Koken Co., Ltd.) was added at a temperature of 4 ° C.
It was dissolved in dilute hydrochloric acid of H3.0 to prepare 0.3 w / v%.
A pH 7.4 phosphate buffer was added while stirring at 4 ° C. to give a collagen solution having a final concentration of 0.1 w / v%. Next, a non-woven fabric made of sodium carboxymethyl cellulose is coated with the collagen solution prepared above and dried in an incubator at 37 ° C. for 4 hours.
Dried on a clean bench. Further, it was immersed in a hexane solution of 5% medical grade silastic silicone for 10 seconds, and then dried in a clean bench.

Next, a 60% polyurethane adhesive was applied onto a release paper using an applicator to form a film, and immediately after the application, the above-mentioned non-woven fabric was placed on the wet layer and the temperature was maintained at room temperature for 10 minutes.
After standing for a minute, it was cured in an oven at 80 ° C. for at least 1 hour. Further, the wound-dressing material could be obtained by backing and drying the hydrophilic polypropylene-made porous membrane obtained above and punching it with a punch having a diameter of 1 mm at regular intervals.

Example 6 Experiment of Transplanting Wound Dressing on Mini Pig Skin Defect Wound The wound dressing obtained in Examples 1 to 3 was transplanted to the dorsal skin of a mini pig and tested. Yucatan micro pig (10
15 kg) was pre-administered with atropine sulfate (0.05 mg / kg) and azaperone (2 mg / kg) (in blood), and after 10 to 15 minutes, ketamine (15 mg / kg (in blood)) was introduced. Furthermore, maintenance anesthesia was performed with Nembutal 10 mg / kg (subcutaneous). After anesthesia, the dorsal skin of the miniature pig was extensively shaved and used as the surgical field. After sterilizing thoroughly, a skin layer of 3 × 3 cm (10/1000 inch) was prepared in the center of the back by a dermatome, the wound dressing was placed on the wound, and the non-adhesive dressing (Primapore Smith and (Made by Nephew) was placed thereon, and the inside was further covered with a stretchable inside drape (Sude) drape, manufactured by 3S Co., Ltd., and then fixed using a stretch tape. The state of healing was observed after 3 and 14 days.

On the third day, all the coating materials were in close contact with each other, and the through holes were almost filled with blood. After 14 days, the epidermis was regenerated and the covering material could be easily peeled off from the wound surface.

[0036]

EFFECTS OF THE INVENTION The wound dressing of the present invention comprises a support layer and an adhesive layer formed of a biocompatible highly water-containing gel-forming substance thin film in which a site that can come into contact with a wound is coated with a water-repellent substance. And a hydrophilic porous membrane are laminated, and since they have through holes, when applied to the affected area due to a disease such as a burn, a skin-wound and a skin-exfoliated wound, a traumatic skin defect wound, or a wound. In addition, since the exudate or blood does not accumulate under the covering material and adheres closely to prevent infection and pain, and the contact site with the wound surface has biocompatibility, the covering material sticks to the wound surface and peels off. It does not cause bleeding, pain, etc., promotes healing of the wound, and can be regenerated cleanly without leaving a scar.

Claims (1)

[Claims] 1. A laminated structure in which a support layer made of a carboxymethyl cellulose nonwoven fabric coated with a water-repellent material, an adhesive layer, and a hydrophilic porous membrane are laminated, and the laminated structure has a diameter of 1 to 3 mm. A wound dressing characterized by having a through hole of a diameter.