NZ198344A - A bandage containing a medicament - Google Patents

Description

' V'^*WT7' " Priority Dat©(s): Ccmplots Specification Filed: .ft.'fL'&t CEs^s'i i^l!. .1 i«m *.». i/r#A ji * ■ ■ i\ JuLtySft.

Publication Data: . .V.

P.O. Journal No: ■ A^pP.

I 983 44 r f4SEP 1981 Patents Form No. 5 NEW ZEALAND PATENTS ACT 195 3 COMPLETE SPECIFICATION "IMPROVED BANDAGE CONTAINING A MEDICAMENT" Jr/WE ADVANCE ELECTRODE KABUSHIKIKAISYA, a Japanese Corporation, of 7058-1, Fuchu-shi, Tokyo, Japan, s hereby declare the invention, for which -I-/we pray that a patent may be granted to ine/us , and the method by which it is to be performed, to be particularly described in and by the following statement:- • (followed by page I A.) 1 983 - 1A - IMPROVED BANDAGE CONTAINING A MEDICAMENT BACKGROUND OF THE INVENTION This invention relates to an improved bandage which contains a medicament that is topically released into the skin.

Attempts have been made to develop bandages which are self-adhesive, absorbent, and sterile. For example, U.S. Patent No. 3,339,546 discloses a self-adhesive bandage which is adapted to adhere to moist surfaces such as the moist mucosa of the oral cavity. However, one of the 10 essential materials of this self-adhesive bandage is an adhesive gum, preferably polyisobutylene, which is hydrophobic. Similarly, U.S. Patent Nos. 3,598,122 and 3,598,123 disclose bandages which contain drugs that are continually released from an adhesive layer. These bandages are formed 15 of layered materials which have drugs encapsulated in the adhesive layer. Even though the bandage disclosed in there prior art patents are said to be self-adhesive and are satisfactory vehicles for drugs, specific process steps are required for encapsulating or stratifying the drugs. 20 SUMMARY OF THE INVENTION Therefore, it is a general object of this invention to provide a self-adhesive, novel bandage in which a medicament is molecularly dispensed for release to the affected area. The bandage is comprised of a flexible backing element and 25 a self-adhesive substrate which becomes increasingly tacky in the presence of moisture and which absorbs liquid and 1 98344 releases the medicament to the affected area while remaining dimensionally stable.

These and other objects and advantages of this -invention will more fully appear from the following de-5 scription made in connection with the accompanying drawings, wherein like reference characters refer to the same or similar parts throughout the several views.

FIGURES OF THE DRAWINGS Fig. 1 is a perspective view illustrating the novel 10 bandage applied to the arm of a patient.

Fig. 2 is a perspective view of a bandage illustrated in Fig. 1.

Fig. 3 is a perspective view of a bandage used as a surgical dressing.

Fig. 4 is a cross-sectional view taken approximately along line 4-4 of Fig. 2 and looking in the direction of the arrows.

Fig. 5 is a modified form of the bandage.

DESCRIPTION OF THE PREFERRED EMBODIMENT 20 The bandage of the present invention has adhesive properties for maintaining contact with the skin, as well as possessing a certain amount of elasticity for movement with the skin. The bandage is intended to be easily handled and is non-irritating to the patient. 25 Referring now to the drawings, it will be seen that the bandage of the present invention is thereshown. The bandage, designated generally by the reference numeral 10, includes a backing member 11 and a self-adhesive 1 98344 substrate 12 which is secured to one end surface of the backing. The backing element 11 and the substrate 12 are both illustrated as rectangular sheets of material of uniform thickness. It is pointed out that the bandage 10 5 is intended to be regular in shape but may have any other configuration although the rectangular shape is preferred. In use, the bandage is applied with the substrate 12 in direct contact with the skin to cover a non-surgical wound, a surgical wound, or burned tissue. In Fig. 3, the embodi-10 ment illustrated therein is a surgical dressing and will be applied to the patient to cover a surgical wound.

Referring now to Fig. 5, it will be seen that a different embodiment of the bandage, designated generally by the reference numeral 10a, is thereshown. The bandage includes 15 a pressure-sensitive adhesive element 11a which serves as the backing element and also serves as the means for securing the bandage to the surface of the skin. The pressure-sensitive adhesive element 11a may be formed of any of the materials used in commercially available adhesive 2o elements such as a foam-tape adhesive element. It will be appreciated that most of the commercially available adhesive elements maintain an excellent bond with the skin and are not irritable with respect to the skin.

Primary to the unique structure of the bandage is the 25 hydrophilic adhesive properties of the substrate which enhance the adhesion thereof to the skin. The substrate not only absorbs moisture, making it ideal for use as a surgical dressing, but the substrate becomes tackier as it 193344 absorbs moisture.

The substrate 12 may be formed from naturally occurring materials such as gum karaya, guar gum, gum acacia, locust bean gum, and other polysaccharides. The 5 substrate may also be formed from synthetic polymers such as polyacrylamide and its cogeners, such as methylene-Bis-acrylamide, polyacrylic acid molecular weights 250,000, 450,000, 1,000,000 and 4,000,000 and polyacrylamide sold under such trademarks as Reten by 10 Hercules Company. When monomers such as acrylic acid or acrylamide are polymerized, it is necessary to use activators. Activators, which are used during polymerization, may include ferrous sulfate, sodium metabisulfite, potassium persulfate, as set forth in U.S. 15 Patent No. 4,307,717. If the amount of an inorganic activator is less than 1%, it is difficult for a monomer to satisfactorily polymerize, and if the activator is more than 6%, its effects scarcely increase. The disclosure of U.S. Patent No. 4,307,717, is incorporated by reference 20 herein.

The synthetic polymers and/or natural gums and other polysaccharides constitute the solid phase of the matrix. The liquid phase of the matrix preferably consists of alcohols such as glycerol or propylene glycol. Solutions 25 or emulsions of saccharides and/or polysaccharides and/or proteins may be used in forming the matrix.

Alternatively, a combination of a solution or emulsion of polysaccharides, saccharides, or proteins may be used in the liquid phase of the matrix.

The substrate 12 which is a dimensionally stable matrix includes a solid phase comprising a synthetic polymer mixture, a karaya matrix, or a matrix of karaya and synthetic polymer. The solids of the matrix comprise I 98344 % to 50% by weight of the matrix 12. If the matrix contains less than 15% by weight of the solids, it is difficult to maintain its dimensional stability, and if it contains more than 50% by weight of the solids, the matrix 5 loses its flexibility to conform to the shape of the body. The substrate may be sterilized. If the substrate is sterilized, the combination of the mixture is subjected to irradiation (usually gamma rays) of 2.5 mega rads for sterilization. Heretofore, this magnitude of irradiation 10 to mixtures of polysaccharides, such as karaya with an alcohol, preferably glycerol, would cause the matrix to lose dimensional stability with only slight pressure and/or water absorption. This causes the matrix to become so tacky that it is not manageable as a surgical bandage. 15 Further, if this irradiated karaya is used as a sterile pad to seal drainage as noted in the Hollister, U.S.

Patent No. 3,640,741, it may readily break down to a gelatinous substance which may run and break the seal.

The liquid phase of the matrix consists of a solution 20 or emulsion selected from the group comprising carbohydrate, and protein in water and, or ah alcohol and comprises 30% to 70% by weight of the matrix. If the matrix contains less than 30% by weight of the liquid phase, the matrix loses its flexibility, and if it 25 contains more than 70% by weight of the liquid phase, the matrix loses its dimensional stability.

The bandage also includes a suitable backing member which may include cotton fabric, woven or standard paper, synthetic fabrics, and/or plastics. Suitable synthetic 30 fabrics may include nylon or polyester while a suitable plastic backing may include mylar or saran. When the bandage 10 is used as a surgical dressing, the backing element comprises a pervious material such as cotton fabric to permit diffusion of the absorbed liquid into the 35 air.

The substrate 12 also contains a medicinal substance for release to the surface to which the bandage is SP® o 198344 applied. The medicinal substance is molecularly dispersed in the matrix rather than being encapsulated as in the prior art. The medicinal substance may include an antibacterial, antiseptic, or antifunginal agents such as boric acid, bacitracin, acriflavin, formaldehyde, gentia^ violet, mercuric sulfide, mercurochrome, neomycin, and povidone-iodine, i.e., l-vinyl-2-pyrrolidinone polymer compound with iodine, as described in U.S. PharmacopeiaXX P.647 (1980). Nitroglycerine may be used as a coronary vaso dilater agent and hydrocortisone may be used as an anti-inflammatory agent. Suitable antipruretic agents include benzoin , calamine, camphor, menthol, phenol, and sulfur. The substrate may also include fragrances such as cinnamon oil, fir needle oil, lemon oil, peppermint oil, and spearmint. Suitable healing agents include allantoin, Peruvian balsam, Vitamin A, and Vitamin E. Hormonal agents may include estrogen, progesterone, and testosterone. Protective agents may include benzoin, charcoal, talc, and zinc oxide. Salicylic acid is a suitable keratolytic agent and methyl salicylate is a suitable rubefacient. An exemplary antihistamine is chlorpheniramine. If the matrix contains less than 0.1% by weight of the medicament, the bandage loses its pharmacological effects, and if the matrix contains more than 15% by weight of the medicament, the pharmacological effects increase to an unnecessary degree.

The bandage also includes a suitable backing member which may include cotton fabric, woven or standard paper, synthetic fabrics, and plastics. Suitable synthetic fabric may include nylon or polyester while a suitable plastic backing may include mylar or saran.

When karaya or other natural gums are used in forming the matrix, it is necessary to use polyacrylic acid and/or polyacrylamide to protect or compensate degredation of karaya during irradiation, if the matrix is to be 7 sterilized. However, a predetermined concentration of salts, such as aluminium sulfate or sodium chloride, maybe used in the matrix with karaya in some instances in lieu of polyacrylamide and/or polyacrylic acid. For example, concentrations of approximately 6% sodium chloride or aluminium sulphate may be used with karaya in forming the solid phase of the matrix. Inorganic salts such as sodium chloride or aluminium sulfate are effective for the matrix to maintain its dimensional stability during irradiation sterilization when the solid phase contains a natural gum and does not contain an acrylic acid or acrylamide polymer therewith. Thus, if the amount of the salt is less than 1%, the matrix tends to lose its dimensional stability, and if the amount of salts is more than 6%, its effects scarcely increase.

It has been found that vinyl acetate/dioctyl maleate copolymer may also be advantageously used in forming the solid phase of the matrix. Vinyl acetate dioctyl maleate copolymer (sold under the trademark "Flexbond 150" by Air Products and Chemicals, Inc., and sold under the trademark "Bostik 8761" by the Bostik Company, Inc.) will intensify the tackiness of the bandage.

Another important gum material which may be used in forming the matrix is a starch graft copolymer sold under the trade name SGP 502S Absorbent Polymer by the Henkel Corporation, St. Paul, Minnesota. The starch graft copolymer product is derived from corn starch and acrylonitrile and is a graft terpolymer of starch, acrylamide and sodium acrylate. The technical name for this starch graft copolymer product is starch-g-poly (acrylamide-co-sodium acrylate). The starch-g-poly material may be used alone to form the substrate or it may be used in combination with a synthetic gum such as acrylamide or a natural gum such as karaya. The starch-g-poly material is very effective as the skin contacting substrate since it does not maintain its structural integrity and is non-toxic 13 JAM984 Example 1 Polyacrylamide Karaya Glycerol Povidone-Iodine Nominal Amounts of Ingredients % 38% 55% 2% Range of1 Ingredients 1-50% 5-45% 30-70% 0.1-10% Polyacrylic acid Polyacrylamide •' Karaya Glycerol Povidone-Iodine Example 2 % 10% 18% 60% 2% 2-40? 2-4 0' 5-45' 30-70 0.1-10 Polyacrylamide Polyacrylic acid Glycerol Povidone-Iodine Example 3 % 15% 68% 2% 2-4 D% 2-4/1 30-710% 0.1-10% Polyacrylamide Glycerol Methyl salicylate Example 4 % 62% 8% 2-f40% 50470% 0.lfl5% Example 5 Polyacrylamide Polyacrylic acid Glycerol Vinyl acetate/dioctyl maleate Methyl salicylate 21.5% 12.5% 42% 16% 8% >-40% >-40% ) — 7 0 % (0-20% fl-15% Polya!cryl amide Glycerol Water Methyl salicylate Example 6 32% 55% 6% 8% 2-40% 30-70% 1-10% f0.1 15% 1985.4- Example 7 Povidone-Iodine Hydroxy propylcellulose (Klucel) Glycerin Water Polyacrylamide (Reten 421) Namina1 Amounts of Ingredients 2% 6% . 56% ' 6% % Range of Ingredients 0.1-10% 0.1-10% 30-70% 0.1-10% 2-40% Example 8 Povidone-Iodine Reten 4 21 (polyacrylamide) Karaya Glycerol % 5% 35% 50% 0.1-15' 2-4 0i 5-451 30-70 Example 9 Povidone-Iodine Karaya Glycerol Aluminium sulfate 2% 42% 55% 1% Example-10 Camphor Methylenebisacrylamide Acrylic acid Glycerol Activators* 0.1-/5% 0.1410% 0.1+10% 45f-90% 0.1f-2% *Potassium^ersulfate 0.6% metabisulfite 0.2% ferrous sulfate 0.1%- Camphor Glycerol Karaya Sodium chloride Example 10- 2% 50% 43% Of. 1-5% 130-70% 5-45% Example 12- Metliyl—sal leyldte Methylene bisacrylamide Acrylic acid Glyc< .1-10% 0.1-10% 0.1-10% 30-70% 0.1',2,% .

/'S' $ y} y "»>-« - i m ^4% 98 j Example 11 Methyl salicylate Acrylic acid Methylenebisacrylamide Glycerol Karaya Potasium persulfate Nominal Amounts of Ingredients 8% 2% 1% 48% 40% 1% ' Ranye Ingredient^ 0.1-15% 0.1-10% 0.1-1.0% 30-7 0%) ' 5-45%/ 0.1-2% -E-x-am-pl-e—-1-4 Methyl salicylate Karaya Glycerol Vinyl acetate dioctyl maleate copolymj Vinyl acetate ethylene NaCl Methyl salicylate 62% 29% 1% 8% 0.1-19% 5-41% 30-70% 25450% 1+5% O.lf-15% 'acetate Vinyl Kar^aya N^rCl 'ovidone Iodine Example 16 dioctyl maleate 84% J.2% 2% —£%• Example 12 Starch-g-poly Glycerol Nitroglycerine % 62% 8% -50% 30-70% / 0.1—15% Starch-g-poly Glycerol Karaya Nitroglycerine Example 13 % 55% 12% 8% 1-30% 30-70% 5-45% 0.1-15%

Claims (14)

WHAT WE CLAIM IS:

1. A flexible, liquid absorbent, adhesive bandage to be applied to a patient, comprising: a flexible backing element selected from the group comprising cotton, paper, synthetic fabric, and plastic, a substrate attached to said backing element comprising a homogeneous, hydrophilic matrix being dimensionally stable in irradiation sterilization and sufficiently pliant to conform to the shape of the body contours, said matrix including, based on the weight of said matrix, 15% to 50% by weight of a solid phase formed from a hydrophilic high-molecular polysaccharide and/or synthetic gum selected from the group comprising polyacrylic acid, polyacrylamide, and their cogeners, vinyl acetate/ethylene copolymer, vinyl acetate/dioctyl copolymer, natural gums, and starch-g-poly (acrylamide-co-sodium acrylate), and 30% to 70% by weight of a liquid phase consisting of a solution or emulsion selected from the group comprising carbohydrate, and protein in water and/or an alcohol, said matrix containing 0.1% to 15% by weight of a medicament selected from the group including vaso-dilators, an antibacterial agent, antiseptic agent, antifungal agent, antihistamine agent, anti-inflammatory agent, antipruritic agent, hormonal agent, keratolytic agent, skin protective agent, and rubefacient agent, said matrix containing 1% to 6% by weight of an inorganic salt selected from the group including a dimensional stabilizer, where said solid phase contains a natural gum and does not contain polyacrylic acid and/or polyacrylamide, and their cogeners, and a polymerization activator where an acrylic acid and/or acrylamide, and their cogeners are formulated as a monomer, said bandage having an adhesive surface for contact with and adhesion to a patient's skin.

2. The bandage as defined in claim 1 wherein said liquid 198344 - 12 - 15 phase comprises a solution of a polysaccharide.

3. The bandage as defined in claim 1 wherein said liquid phase comprises an alcohol.

4. The bandage as defined in claim 1 wherein the solid 5 phase of matrix includes a natural gum selected from the group comprising gum karaya, gum acacia, locust bean gum, and guar gum.

5. The bandage as defined in claim 4 wherein said liquid phase comprises glycerol. 10 6.

The bandage as defined in claim 3 wherein said medicament comprises 0.1% to 15% by weight of done-iodine as an antibacterial agent.

The bandage as defined in claim 3 wherein said medicament comprises 0.1% to 5% by weight of camphor as an antipruritic agent.

8. The bandage as defined in claim 4 wherein said medicament comprises 0.1% to 5% by weight of camphor as an antipruritic agent.

9. The bandage as defined in claim 3 wherein said 2 0 medicament comprises 0.1% to 15% by weight of methyl salicylate as a rubefacient agent.

10. The bandage as defined in claim 1 wherein said matrix has adhesive properties whereby the surface which contacts the skin defines said adhesive surface. 25

11. The bandage as defined in claim 1 wherein said backing element is a pressure-sensitive adhesive element and defines said adhesive surface which contacts the patient's skin.

12. The bandage as defined in claim 1 wherein said 30 medicament comprises 0.1% to 15% by weight of nitroglycerine as a vaso-dilator.

13. The bandage as defined in claim 1 wherein said inorganic salt is selected from the group comprising aluminium sulfate and sodium chloride as a dimension 35 stabilizer. pov 7. - 13 -

14. The bandage as defined in claim 1 wherein said inorganic salt is selected from the group comprising potassium persulfate, sodium metabisulfate, and ferrous sulfate as a polymerization activator. BALDWIN, SON & CARE -amS: a„ohneys fob -the applicants - 13