JPH04371161A - Web of chitin - Google Patents

Abstract

PURPOSE:To provide a web of chitin suitable for use as a wound covering and protecting material for treating deep and wide wounds by using fibers or fibrils of chitin. CONSTITUTION:Chitin fibers are cut into short fibers, e.g. a length of about 1mm-5cm and each of the fibers or fibrils which are a bundle of numerous out in such a way that the chitin fibers which are a bundle of numerous fibers are opened one by one using a card machine or the like for manufacturing wadding so that a web of chitin can be made. In this case, the fibers are crimped in progress in order to make the web entangled well. The web finished may be used directly or may have its fibers lightly stuck to one another by an adhesive. To use webs of chitin as e.g. wound covering and protecting materials, the materials are divided into groups and packed in disinfeting bags and used after disinfection. The webs thus obtained provide good therapeutic effects.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a web-like material made of chitin. In particular, the present invention relates to a chitin web material suitable as a wound treatment material for treating deep wounds in the medical field, such as crush wounds, bedsores, and leg ulcers.

0002

BACKGROUND OF THE INVENTION Although chitin, an aminopolysaccharide, has a chemical structure similar to cellulose, it has many interesting characteristics that are different from cellulose. For example, it has good adsorption properties for metals, proteins, etc. It has also been shown to have the effect of promoting healing when used on wounds in living organisms. Fiber and fibril shapes have long been proposed as shapes that can effectively bring out such effects, and their use as nonwoven fabrics has been proposed, for example, in Japanese Patent Application Laid-Open No. 61-24096.
There is one described in Publication No. 3. However, while these are effective for certain purposes, they are not necessarily sufficient for other purposes. For example, there were also problems with wound treatment.

[0003] General wound treatment techniques have made remarkable progress in recent years, and progress has been made in treating relatively shallow wounds such as burns, trauma, and skin harvest wounds after skin grafts have been removed. Many products are used as wound dressings. These materials can be mainly classified into synthetic materials made of synthetic polymers and biomaterials made of natural polymers. The synthetic material is polyurethane film (product name:
Biomaterials include lyophilized pork skin (trade name: Opsite, Bioclusive), polyurethane sponge (trade name: Duoactive), nylon fiber coated with polypeptide (trade name: BioBrene), etc. : Aroask), collagen fiber sheet (product name:
May Pack), chitin fiber sheet (trade name: Veschitin W), etc.

[0004] All of these methods treat shallow wounds, but in the case of deep wounds such as crush wounds, bedsores, leg ulcers, etc., not only the skin but also the granulation tissue will be severely damaged. The reality is that it is difficult to treat with the above-mentioned wound dressings because it results in a deep three-dimensional wound, has a lot of exudate, and is prone to infection. For example, synthetic materials do not remove exudate from the wound, causing it to pool in the wound, further delaying healing. In addition, in the case of biomaterials, removal of exudate is relatively sufficient, but since they are in the form of thin sheets, they may not adhere well to the three-dimensional wound surface.
The reality is that it often melts due to exudate and cannot be expected to provide sufficient protection. Therefore, the current treatments for these deep wounds include protecting them with pharmacopoeial gauze coated with ointment containing an antibacterial agent or polyvinylpyrrolidone solution containing iodine.
Treatment is aimed solely at removal of exudate and disinfection.

[0005]

[Problem to be solved by the invention] In this kind of treatment,
Early granulation and epidermal formation cannot be expected. The goal of wound treatment is to bring the wound to a state of healing as quickly as possible. To this end, the role of a wound covering material is to be able to adhere to and protect the wound surface sufficiently, to absorb exudate sufficiently and to expel it outside the wound, and to promote granulation and epidermis formation. Can, also,
It is preferable that it be easily replaceable during treatment.

[0006] "Beskitin W" (manufactured by Unitika), a sheet made of chitin nonwoven fabric, is already on the market.
It is preferably used to protect many wounds and is well received. It is particularly characterized by good granulation and epidermis formation. However, this material is not necessarily suitable for use against deep scratches.

Under these circumstances, an object of the present invention is to provide a chitin web-like material suitable as a wound covering material for treating deep and wide wounds.

[0008]

[Means for Solving the Problems] As a result of intensive research to achieve the above object, the present inventor found that a chitin web-like material made of chitin fibers or fibrils can solve the problems, and the present invention has been made. has been reached.

That is, the gist of the present invention is a chitin web-like material made of chitin fibers or fibrils.

The present invention will be explained in detail below. Chitin is poly(N-acetyl-D-glucosamine) obtained by treating the exoskeleton of crustaceans, insects, etc. with hydrochloric acid and caustic soda to remove ash and protein substances, or this poly(N-acetyl-D-glucosamine). - Deacetylated product obtained by treating glucosamine) with concentrated alkali (several % deacetylation degree)
Among them, chitosan has a high degree of deacetylation and is soluble in acids, and is particularly called chitosan.

[0011] The chitin used in the present invention is such chitin, deacetylated chitin, or chitosan, and furthermore, the -OH group, -CH2 OH group, or amino group of the glucosamine residue of chitin or chitosan is an ester. It also includes chitin derivatives which have been oxidized, etherified, carboxymethylated, hydroxyethylated or O-ethylated.

[0012] Chitin fibers or fibrils refer to fibers or fibrils obtained by dissolving chitin in a solvent to form a solution. There are basically two ways to make a chitin solution. One is the case of chitin with a low degree of deacetylation, and these solvents include dimethylacetamide or a mixture of N-methylpyrrolidone and lithium chloride, a mixture of trichloroacetic acid and halogenated hydrocarbons, etc. There is. When chitin is dissolved in powder form in these solvents at a concentration of about 2 to 10% by weight, a viscous and transparent solution can be produced. To make fibers from these,
For example, by pumping a measured amount of liquid from a pressurized tank using a gear pump, etc.
There is a method in which the material is extruded into a coagulating liquid such as water or alcohol through a nozzle containing a filter, for example, a fine hole of about 0.07 mmφ, and after solidifying, it is withdrawn at a constant speed. The resulting fibers are thoroughly cleaned of impurities such as solvent and coagulation liquid. The thickness of each fiber when used in the present invention is 0.
It is about 2 to 50 deniers, preferably 0.5 to 10 deniers.

Regarding fibrils, it is possible to introduce them into the coagulation solution while stirring the solution, or to add a water-soluble substance or a water-soluble substance to the chitin solution.
For example, it can be obtained by mixing polyglycerin or the like, thoroughly mixing the solution, and removing water-soluble substances with hot water.

[0014] Here, fiber means something with a uniform cross-sectional shape in the longitudinal direction and is created endlessly, whereas fibril means something with a non-uniform cross-sectional shape in the longitudinal direction and a long length. means relatively short.

Deacetylated chitin fibers or fibrils are prepared by adding these chitin fibers or fibrils to a concentrated aqueous solution of caustic soda, for example at a concentration of 10 to 30% by weight, at 80°C.
It can be created by processing at a temperature above. The degree of deacetylation can be adjusted by adjusting the concentration of caustic soda, temperature, and treatment time.

To make fibers or fibrils from chitin with a high degree of deacetylation, such as chitosan, an aqueous solution of acetic acid, for example, can be used as the solvent. For example, when 0.5 to 10% by weight of chitosan is dissolved in an aqueous solution containing about 0.1 to 5% by weight of acetic acid, a transparent and viscous solution is produced.

[0017] As in the case of the chitin solution, this is placed in a pressurized tank, measured using a gear pump, and discharged from a fine nozzle. As the coagulating liquid, simple water, alcohol or alkaline aqueous solution, alcoholic liquid containing alkali, etc. can be used. Chitosan fibers can be obtained by taking the coagulated fibers at a constant speed and thoroughly washing them to remove impurities such as the solvent and coagulating liquid. The thickness of each fiber or fibril used in the present invention is also about 0.2 to 50 deniers, preferably 0.5 to 1 denier.
It is 0 denier. These fibers or fibrils may be used as they are, or may be treated in alcohol containing acetic anhydride to advance acetylation of some amino groups.

[0018] The chitin web consisting of these chitin fibers or fibrils means a flocculent aggregate of these fibers or fibrils. This manufacturing method can be carried out by first cutting chitin fibers into short fibers, for example, lengths of about 1 mm to 5 cm, and opening each fiber or fibril one by one. For example, by opening a large number of bundled chitin fibers one by one using a card machine that produces futon cotton, a web-like product can be created. At this time, the fibers may be crimped in advance to improve the entanglement of the web-like material.

The completed web-like material may be used as it is, or may be slightly pressed from above to form a mat-like material, or the fibers may be lightly adhered with an adhesive. In order to use these web-like materials, for example, as wound dressings, they can be divided into portions, packed into sterile bags, and used after sterilization. Note that these web-like materials can also be used by applying drugs such as antibiotics, bactericidal agents, and wound treatment agents.

[0020] When the web-like material of the present invention thus obtained is used to treat deep wounds such as crush wounds, bedsores, and leg ulcers, it has an excellent effect of eliminating exudate, has good adhesion, and inhibits granulation formation. Since it is excellent in epidermal formation, it can produce good therapeutic effects.

[0021]

EXAMPLES The present invention will now be explained in more detail by way of examples. Example 1 Crude chitin powder (manufactured by Shin Nippon Chemical) was heated at 40°C in 1N hydrochloric acid.
, treated for 1 hour, and further treated in a 3% caustic soda aqueous solution for 9 hours.
Heat treatment was performed at 0°C for 3 hours to remove calcium and protein contained in the crude chitin powder. This chitin powder was mixed with a mixed solvent of dimethylacetamide and lithium chloride (
A transparent solution was prepared by dissolving 6% by weight in a weight ratio of 92:8). After filtering this solution through a 1480 mesh stainless steel net, it is packed in a tank, pumped with a gear pump while pressurized with compressed air, extruded through a 0.05 mmφ nozzle into hot water at 80°C, and after solidifying, the solution is heated for 10 m /min
When the fibers were taken up at a speed of 1 and washed thoroughly with hot water again, chitin fibers with a single filament denier of 0.8 denier were obtained. After drying this, it was cut into lengths of 1 cm, and a web-like material of chitin fibers was created using a fiber opening card machine. This web-like material was packed into a sterile bag, sterilized, and then used to treat pressure ulcers.

The patient was a 78-year-old woman who became partially paralyzed due to a brain injury and suffered a pressure sore on her sacrum due to being bedridden. The patient was treated with a povidone-iodine solution for a while after the injury, but the results were not satisfactory, so the patient was treated with the web-like material of this example. At the start of treatment, the wound area was 6 cm x 10 cm oval, and its depth reached the muscle. The treatment involved first thoroughly cleaning and sterilizing the affected area with local gauze soaked in Oxyur, and then lightly compressing and filling the wound surface with chitin cotton. A piece of gauze was placed over it and fixed with adhesive tape. Exchanges were performed every 2 days, and the treatment method was the same as the first time.

[0023] As a result, formation of high-quality granulation was observed from around the 6th day, and as the days passed, granulation formation became better.
The size of the wound has also decreased. Finally, within 45 days, the wound completely closed and he was completely healed.

Example 2 The chitin fibers obtained in Example 1 were treated in a 20% by weight caustic soda solution at 90° C. for 2 hours. After thorough washing with water, the degree of deacetylation of this fiber was measured and found to be 55%. This fiber was cut into 15 mm pieces, and a web-like product was also created using an opening card machine and then sterilized.

[0025] This web-like material was used to treat a crush injury of a 19-year-old man who had been injured in a motorcycle accident. The injured area was the heel of the left foot, and the wound was locally deep, exposing the bone and tendon. Immediately after treatment, she was treated with DuoDerm (manufactured by Nippon Squibb), but there was no tendency to improve at all.
The web-like material of this example was used instead. Treatment consisted of thoroughly cleaning the affected area with saline and povidone-iodine solution, then filling the wound surface with a chitin web-like material under pressure, placing gauze over it, and fixing it with adhesive tape. Furthermore, the surrounding area was protected with a bandage. The chitin web was replaced every 5 days. At the time of replacement, a large amount of exudate was observed on the gauze side.

[0026] On the first 5 days, good granulation was already formed even in the exposed bones and tendons, and as the treatment was continued, it became even better on the 10th and 15th days.
On the 5th day, granulation and epidermis formation were completed, and the affected area was completely healed. It should be noted that during replacement, it was very easy to remove the chitin web-like material.

Example 3 Chitosan powder (manufactured by Shin Nippon Chemical Co., Ltd., 0.2% in a 2% acetic acid aqueous solution)
% dissolved solution viscosity was 250 centipoise (B-type rotational viscometer 1000 rpm) was dissolved at 3% by weight in a 3% acetic acid aqueous solution to obtain a viscous and transparent solution. The solution was filtered through 1480 mesh stainless steel net, placed in a pressurized tank, and metered by a gear pump. Furthermore, 0.07m
After being discharged from a fine nozzle of mφ into an aqueous solution containing 0.5% caustic soda and solidified, it was wound up at a speed of 8 m/min. When the obtained fibers were thoroughly washed, chitosan fibers having a single yarn denier of about 1.5 denier were obtained. After cutting this fiber into a length of 20 mm, a chitosan web-like material was obtained using a fiber opening card machine. This was pressed into a sheet-like mat. After further sterilization, it was used to treat leg ulcers.

The patient was a 68-year-old woman who had developed an ulcer in her lower leg due to poor venous blood circulation. After injury, approx. 2
Treatment with antibiotic ointment was continued for several months, but there was no sign of improvement at all. For treatment, first, the affected area was thoroughly washed with povidone-iodine solution, then a chitosan web mat was applied with light pressure, and the upper layer was covered with gauze and fixed with adhesive tape. The chitosan web mat was replaced every 3 days. At the time of replacement, there was a large amount of exudate on the gauze side. From around the 12th day, high-quality granulation begins to form, and on the 27th day, epidermis formation is completed.
Completely recovered.

[0029]

[Effect of the invention] The chitin web-like material of the present invention can be used as an adsorbent,
When used in medical products, etc., especially as a wound dressing, it adheres well to the affected area, has an excellent exudate removal effect, and is also excellent in granulation and epidermis formation, so it can be used for deep wounds, e.g. It can be used for crush injuries, bedsores, leg ulcers, etc., and can be highly effective.

Claims (1)

[Claims] 1. A chitin web consisting of chitin fibers or fibrils.