JPS59155248A - Coating membrane and production thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Background of the Invention Technical Field The present invention relates to a novel coating film and a method for producing the same.

More specifically, the present invention relates to a coating film made of insolubilized keratin having specific physical properties and a method for producing the same.

When skin is damaged by wounds, burns, wounds, etc., it is ideal to collect one's own skin from another site and transplant it for treatment. However, there are limits to the area and amount that can be collected, so when the affected area is large, an artificial covering membrane is usually used. The coating film of the present invention is used to protect and treat such damaged skin.

Prior Art Conventionally, freeze-dried pork skin, nylos sheet, silicone gauze, silicone rubber membrane, membrane made by solidifying blood plasma, fibrin membrane, oil-processed gauze, etc. have been used as coating membranes for the above purpose. It had been. However, these have various problems in terms of compatibility with the affected area, water vapor permeability, and ability to prevent bacterial infection. Recently, a coating film using colladan has been proposed (US Pat. No. 4,280,954). The collagen coating has excellent biocompatibility. However, collagen has the disadvantage that membrane preparation is not easy. That is, colladan cannot be prepared into a highly concentrated aqueous solution and does not dissolve in water unless the pH is around 3, so a neutralization operation is required afterwards. In addition, it is difficult to handle due to its high viscosity, and when insolubilizing it, it is difficult to control the crosslinking reaction.

Furthermore, it does not have good adhesion to the skin and is expensive.

■1 Purpose of the Invention Therefore, the purpose of the present invention is to provide a coating film that has excellent water vapor permeability (moisture permeability), conformability and adhesion to the skin, preventive effect against bacterial infection, etc., is inexpensive, and is easy to form. It is about providing.

According to the present invention, the following coating film and method for manufacturing the same are provided.

(1) Thickness 5-1000μm 1 Moisture permeability 0.1-200m
g/cIrL2・hr and water absorption 0.1-150υ-
A coating film consisting of an insolubilized keratin film having 2.

(2) A coating characterized in that the above-mentioned insolubilized keratin film is produced by dissolving solubilized keratin in water or a mixture of water and alcohol, drying the solution, and immersing the obtained film in an aldehyde solution. Membrane manufacturing method.

(3) A coating film characterized in that the solubilized keratin is dissolved in water or a mixture of water and alcohol, an aldehyde solution is added to the solution, and the mixture is dried to produce the above-mentioned insolubilized keratin film. Manufacturing method.

(4) Solubilized keratin is dissolved in water or a mixture of water and alcohol, the solution is dried, and the resulting film is immersed in water vapor for 1 hour.
．． A method for producing a coating film, characterized in that the above-mentioned insolubilized keratin film is produced by stretching and holding it 5 to 5 times.

(5) Solubilized keratin is dissolved in water or a mixture of water and alcohol, the solution* is dried, and the resulting film is γ-treated under deoxidized conditions.
A method for producing a coating film, characterized in that the keratin film is produced by irradiating the keratin film with radiation or by irradiating it with ultraviolet rays in a nitrogen atmosphere.

(6) A method for producing a coating film, which comprises dissolving solubilized keratin in carboxylic acid and drying the solution to produce the above-mentioned keratin film.

(7) A method for producing a coating film, which comprises producing the above-mentioned insolubilized keratin film by again crosslinking and insolubilizing the solubilized keratin obtained by cutting the crosslinked portion of the claten molecule.

(8) The above-mentioned insolubilized keratin film is produced by dissolving solubilized keratin in water or a mixed solution of water and alcohol, drying the solution, and treating the obtained film with hot water of 45° C. or higher. A method for producing a coating film.

(9) A method for producing a coating film, which comprises dissolving solubilized keratin in water or a mixture of water and alcohol, and heating and dehydrating the solution to produce the above-mentioned insolubilized keratin film.

■1 Detailed description of the invention As mentioned above, the coating film of the present invention has a thickness of 5 to 1000 μm.
% moisture permeability 0.1-200'm9/CIrL2・h
It consists of an insolubilized keratin film having r and water absorption of 0.1 to 150 P/cIn2.

The above-mentioned thickness of the keratin film is necessary in order to maintain the above-mentioned strength and coating effect. Moisture permeability is necessary to prevent tissue destruction at the wound surface, and water absorption, which is expressed by the amount of water vapor that evaporates per unit time through a membrane with a unit area of close contact, is necessary to absorb and remove excess body fluid that has exuded. It is expressed as the amount of water absorbed per unit area of the membrane.

The numerical values of the above-mentioned physical properties that the keratin film should have are not necessarily critical, but in order to fulfill the function as a coating film, it is necessary that they be within the range of the above-mentioned numerical values. It is selected as appropriate depending on the situation in which it is used. For example, in the early stages of a burn injury, there is a lot of exudation of body fluids, so an insolubilized keratin film with high water absorption and moisture permeability is used to evaporate moisture and heat.

The insolubilized keratin of the present invention can be produced by various methods shown below.

(1) Solubilized keratin is dissolved in water or a mixture of water and alcohol, the solution is placed in a dish and dried, and the resulting film is dissolved in an aldehyde solution such as a glutaraldehyde solution or a formaldehyde solution, especially a glutaraldehyde solution. Soak and insolubilize.

Solubilized keratin can be dissolved up to about 10% in water, but is preferably dissolved at a 5% concentration and dried in a dish. The produced membrane is immersed in a 25% glutaraldehyde solution for 2 hours or more, then washed with water and dried. Drying may be air drying or freeze drying.

Distilled water can be conveniently used as water, but if a higher concentration keratin solution is desired to be prepared, the solubility can be increased by adjusting the pH to the acidic or alkaline side. For example, when Cal is oxymethylated solubilized keratin, its solubility becomes very high at pH 1-2 or pH 8-9.

(2) Add an aldehyde solution, especially a glutaraldehyde solution to the solution of solubilized keratin, and place the mixture in a dish and dry. Glutaraldehyde is preferably added to a concentration of about 0.5%.

(3) Pour the solubilized keratin solution into a dish and dry it.
The obtained membrane is slowly stretched 1.5 to 5 times (preferably 25 to 4 times) in water vapor and held in this state for 30 minutes or more, preferably 3 hours or more.

(4) A solution of solubilized keratin is placed in a dish, dried, and the resulting membrane is heated to 4 Mrad or more (preferably 6 to 6 Mrad) under deoxidized conditions.
10 Mrad) or ultraviolet rays under a nitrogen atmosphere.

(5) Solubilized keratin aqueous solution with carboxylic acid, especially formic acid,
Trihaloacetic acid (eg, trichloroacetic acid, tribromoacetic acid) is dissolved in dihaloacetic acid (eg, dichloroacetic acid, dibromoacetic acid) at a ratio of about 5%, and the solution is placed in a ft dish and dried. Although other carboxylic acids can also be used, the above carboxylic acids have high solubility and are particularly preferred.

(6) The solubilized keratin obtained by cutting the crosslinked part of the keratin molecule is crosslinked again to make it insolubilized. That is, wool is reduced with trilobe tylphosphine, formic acid is added to the wool, and the wool is treated with ultrasound. A coated membrane is obtained by forming a membrane from the supernatant after centrifugation. Or O'Done
The wool is reduced according to the method of ll, and the soluble part is
It can also be obtained by adjusting the composition, dialyzing it, and then forming a cast film.

(7) It can be obtained by dissolving solubilized keratin in water or a mixture of water and alcohol, drying the solution, and treating the obtained film with hot water at 45° C. or higher.

(8) It can be obtained by dissolving solubilized keratin in water or a mixture of water and alcohol, and heating and dehydrating the solution. The heat dehydration treatment is preferably performed at a temperature of 45° C. or higher.

The solubilized keratin used as a starting material in the process of the present invention can be prepared by methods known per se, such as O'Tunnel (0'D
(1, J, O'Donel) et al.
let-al Au5t, J, Biol, Set
, Vol. 17, p. 973, 1964). That is, it is obtained by adding wool to a urea solution, treating with mercaptoethanol and then iodoacetic acid, filtration, dialysis, and centrifugation. Alternatively, an oxidation method in which wool is treated with performic acid (S, Moore + Journa
of Biological Chemistry
238, p. 235, 1963).

The insolubilized keratin film of the present invention is a glue-like film that absorbs body fluids and adheres closely to the skin, thereby providing an environment suitable for healing without creating gaps where bacteria can enter. Furthermore, it is possible to control the degree of absorption into the living body. Furthermore, the insolubilized keratin membrane of the present invention does not allow even minute bacteria such as Serratia to pass through, so it is possible to keep the wound sterile and prevent secondary infection by bacteria.

Next, the present invention will be explained in further detail by showing Examples and Test Examples.

Example (Preparation of solubilized keratin) (Part 1) Wool (Woo I Top) pH adjusted to 1.77 with hydrochloric acid
95m7 of 8M urea solution adjusted to 7.4! and add 0.0 of tris(hydroxymethyl)aminoethane to this mixture.
2M and disodium ethylenenoaminetetraacetic acid (ED
After adding 0.001M of TA-2Na) and substituting with nitrogen gas, mercaptoethanol 1rn1. Add 5NK
Adjust the pH to 10.3 with OH. Stir for 3 to 4 hours, add 2.68 p of iodoacetic acid, and adjust to pH 8 with 5 N KOH.
Adjust to 5. - After stirring at night, filter using Nutze filter, and the filtration result is about 100-110 dt - Dialyze for 5 days. If using a hemodialyzer, dialyze and concentrate for about 6 hours. The dialyzed residue was centrifuged at 11,000 Orp for 1 hour, and the supernatant was lyophilized to give solubilized keratin o, 6sg- (yield 4
o~60%) is obtained.

(Part 2) 277 parts of formic acid and 37 parts of hydrogen peroxide! was added dropwise under cooling, and then stirred at room temperature for 2 hours. A piece of wool 1.07cm is immersed in the performic acid solution obtained. After leaving it in the dark for 24 hours, it is filtered using a glass filter (G3). pH of the remaining liquid
11 Add to 150 d of ammonia solution and stir for 2 hours. Adjust the pH to 10.3 with ammonia, stir for 24 hours, centrifuge at 10.00 Orpm for 1 hour, and freeze-dry the supernatant to obtain solubilized keratin (yield 40-5.
0%).

Manufacture of coating film (method a) Solubilized keratin is dissolved in distilled water to make a 5% aqueous solution.

This is dispensed into a Teflon dish at a volume of 0.16 ml/crrL2 and air-dried to obtain a solubilized keratin film with a thickness of about 50 to 60 μm. .

The membrane thus obtained was dissolved in 25% glutaraldehyde solution.
Soak for an hour. Wash thoroughly with water to obtain the desired coating film.

(Method b) Add glutaraldehyde solution to a concentration of about 0.5% to a 5% solubilized keratin solution, dispense the resulting solution into a Teflon dish at a concentration of 0.16 me/cnL2, and air dry. .

(Method C) The solubilized keratin film obtained in the same manner as in Method a is slowly stretched 4 times in steam and held in that state for 3 hours.

(Method d) A solubilized keratin film obtained in the same manner as in Method a is irradiated with γ-rays for 6 hours under deoxidized conditions. Alternatively, one side is irradiated with ultraviolet rays for 3 hours from a distance of 10 cIrL using a 4W ultraviolet lamp in a nitrogen atmosphere.

(e method) Solubilized keratin is dissolved in formic acid to make a 5% formic acid solution.

The solution was dispensed into a Teflon dish at a volume of 0.16 ml/an and air-dried.

(Method f) According to O'Donell's method, wool is reduced, the soluble portion is adjusted to pH 5, dialyzed, and then cast into a film.

(Method g) Solubilized keratin is dissolved in distilled water, and the aqueous solution is placed in a dish and air-dried. The obtained film was placed in warm water at t-80°C for 15 minutes, pulled up, and then dried.

(Method h) Solubilized keratin is dissolved in distilled water. This is placed in a dish and dehydrated and dried at a temperature of 80°C.

Table 1 shows the physical properties of the coating films obtained in the above (method g) to (method h).

Table 1 Methods for Measuring Physical Properties of Coating Films Tests were conducted based on moisture permeability method (JIS Z1504) K. However, so that the water is always in contact with the membrane, a sponge with a thickness that is just in contact with the membrane is placed in the container, and distilled water is dispensed. Further, the storage conditions were a temperature of 37° C. and a humidity of 45%.

Take out the membrane that has been left in water-absorbing distilled water for 24 hours or more, remove the moisture on the surface, and then leave it at a temperature of 37°C and humidity of 45°C until it reaches a constant weight, and divide the weight difference before and after leaving it by the surface area.

Test method A skin pocket is created under the skin on the back of a female guinea pig (approximately 2ooy). After implanting a 1 cm x 1 cm sample, the skins are garbed together.

After a certain period of time, the guinea pig's skin is cut and peeled off, and the condition of the sample is observed. The results are shown in Table 2.

Table 2 1) Absorption layer 1, no change in sample 2, strength slightly decreased but no change in shape 3, prostitute/slut absorption. or completely weakened.

4. Slightly remaining.

5. There is no sample left.

2) Foreign body reaction - no reaction ± slight foreign body reaction 10 Severe foreign body reaction 3) Granulation formation ■, no at all 2 Slight granulation formation 3, granulation formation spread over the entire surface of the sample 4 Thick granulation formation covering the entire surface of the sample 2 It is clear from this that the coating membrane of the present invention, when implanted subcutaneously, does not exhibit any foreign body reaction, similar to the control. The degree of absorption into the body varies depending on the manufacturing method, but it is equal to or higher than the control.

Note that "absorption" means that the membrane ceases to function when it is buried in a living body or kept in close contact with a wound or the like for several weeks or more. For example, it refers to a material whose strength has been extremely reduced and which has partially melted. Granulation is one of the reactions that a living body exhibits when a foreign body is implanted, and is actively formed after implantation, and disappears as the foreign body is assimilated and absorbed. If granulation remains, it will leave a scar, so it is desirable that it disappear as much as possible, but Table 2 shows that the coating film of the present invention is excellent in this respect as well. In addition, thickness outside the range not shown in the table: 5 to 1000μm1 Moisture permeability: 0.1 to 20υ
Q/ari2・hr, water absorption 0.1-150 P/
Similar results were obtained for cm2.

Agar 15.0g - Sodium chloride 5.0p Guin decomposition product of soybean powder 5,01 Noguin creatine decomposition product of casein 15.0% The above method (a) or (h) The membrane prepared by method was placed on 107 pieces of Serratia marcescens (5err).
atia marcescens) suspension 'f: 1-
Dispensed. After 3 hours, remove the bacterial solution along with the membrane and remove the culture medium.
Cultured at 1°C.

After 24 hours, bacterial growth was observed, and no bacterial growth was observed in any of the membranes used.

(1) Effects of the Invention According to the present invention, firstly, a coating film is provided that does not cause foreign body reactions in living organisms and has excellent adaptability and adhesion to the skin. The keratin membrane used in the present invention can be assimilated and absorbed by living organisms due to its preparation method, and has excellent adhesion to wounds, leaving no gaps for bacteria to enter. Furthermore, if it is absorbed into the living body, there is no need to peel it off, and even when it is peeled off, it can be easily peeled off because it is softened. In addition, unlike gauze, it does not penetrate into the formed incipient buds, so it can be removed without damaging the wound.

Second, according to the present invention, a coating film having appropriate thickness, moisture permeability, and water absorption is provided. These physical properties are appropriately selected within the scope of the present invention, depending on the state of the wound, the location, etc. For example, in the early stages of a burn, body fluid secretion is active, so a coating film with high water absorption and moisture permeability is selected.

In addition, when the wound is dry, a material with high water retention is selected and can be impregnated with a soluble drug to promote the healing effect. In this case as well, tissue destruction on the wound surface can be prevented by providing appropriate moisture permeability.

However, since the coating membrane of the present invention does not allow bacteria to pass through,
Wounds can be kept sterile, which is extremely useful therapeutically.

Thirdly, the present invention provides an advantageous method for manufacturing the above-mentioned coating film. All of the manufacturing methods of the present invention are simple to operate and easy to implement. In addition, by selecting an appropriate manufacturing method, or even in one manufacturing method, by appropriately selecting the keratin insolubilization conditions, it is possible to create coatings with different thicknesses, moisture permeability, and water absorption. Membranes can be manufactured.

Furthermore, depending on the preparation method, it is possible to create a film that does not absorb at all in 10 weeks. This type of membrane has a long-term
It is very effective when protection of D wounds is required, and it does not cause pain to the patient as there is no need to change the membrane patch.

Claims (9)

[Claims] (1) Thickness 5~1000'#l, moisture permeability 0.1~20
0rlU; l/cm2-h r i- and water absorption 0,
1 to 15 (l Coating film consisting of an insolubilized keratin film having VcrL2. (2) Solubilized keratin is dissolved in water or a mixture of water and alcohol, the solution is dried, and the resulting membrane is immersed in an aldehyde solution to a thickness of 5 to 1000 μm and a moisture permeability of 0.1.
~200mg/cTL2・hr and water absorption 0.1
A method for producing a coating film, characterized by producing an insolubilized keratin film having a sap h2 of ~150. (3) Solubilized keratin is dissolved in water or a mixed solution of water and alcohol, an aldehyde solution is added to the solution, and the mixed solution is dried to a thickness of 5 to 1000 μm1 moisture permeability of 0.1 to 200
m9/CrrL2・hr and water absorption 0.1-150
1. A method for producing a coating film, which comprises producing an insolubilized keratin film having a particle diameter of P/cm2. (4) Solubilized keratin is dissolved in water or a mixture of water and alcohol, the solution is dried, and the resulting film is immersed in water vapor for 1 hour.
．． A coated film characterized by producing an insolubilized keratin film having a thickness of 5 to 1000 μm, a moisture permeability of 0.1 to 200 mg/cIrL2·hr, and a water absorption of 0.1 to 150 g/cIfL2 by stretching and holding 5 to 5 times. Manufacturing method of coating. (5) Solubilized keratin is dissolved in water or a mixture of water and alcohol, the solution is dried, and the resulting film is γ
The thickness is 5 to 1000 μm, the moisture permeability is 0.1 to 200, and the thickness is 2.
A method for producing a coating film, which comprises producing an insolubilized keratin film having an hr and water absorption of 0.1 to 150 VcTL2. (6) Dissolve the solubilized keratin in carboxylic acid and dry the solution to a thickness of 5 to 1000 μm, moisture permeability of 01 to 200 m
gA1rL2・hr and water absorption 0.1-150 juice-2
1. A method for producing a coating film, comprising producing an insolubilized keratin film having the following properties. (7) The solubilized keratin obtained by cutting the crosslinked part of the keratin molecule is crosslinked again to make it insolubilized to a thickness of 5 to 1000 μm.
A method for producing a coating film, which comprises producing an insolubilized keratin film having a m1 moisture permeability of 0.1 to 2 oomg/cIIL2·hr and a water absorption of 0.1 to 150 Lt/CIIL2. (8) Solubilized keratin is dissolved in water or a mixture of water and alcohol, the solution is dried, and the resulting membrane is treated with hot water at 45°C or higher to a thickness of 5 to 1000 ttm and a moisture permeability of 0. A method for producing a coating film, which comprises producing an insolubilized keratin film having a water absorption of 1 to 20 o1 ng/cIrL2·hr and a water absorption of 0.1 to 150 t/cnL"fc. (9) Solubilized keratin is dissolved in water or a mixture of water and alcohol, and the solution is heated and dehydrated to a thickness of 5 to 1000.
μm1 moisture permeability 0.1 to 200 m9/ctrL2・hr
and a method for producing a coating film, which comprises producing an insolubilized keratin film having a water absorption of 0.1 to 150 f/cri2.