JPH07102458A - Chitin web material - Google Patents

Abstract

PURPOSE:To produce an elastic chitin web material suitable for the use in the fields of agriculture and clothes, especially in medical field by mixing a cotton-like chitin with another cotton-like material. CONSTITUTION:Crustacean is treated with hydrochloric acid and caustic soda, the obtained poly-N-acetyl-D-glycosan or its derivative (e.g. deacetylated chitin and chitosan) is dissolved in an organic solvent and the fiber produced by spinning the obtained dope is cut to form a cotton-like chitin. The cotton-like chitin is mixed and interlocked with synthetic fiber or natural fiber (e.g. animal or vegetable natural fiber) to obtain an elastic chitin web material exhibiting the characteristics of chitin, especially the excellent curing effect as a curing and protecting material in medical field.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chitin web-like material having elasticity and formed by mixing cotton-like chitin and a cotton-like material other than chitin. More specifically, it relates to the fields of agriculture, science and clothing. , Which can be used in the medical field, and particularly in the medical field, from a mixture with chitin and a cotton-like material other than chitin, which are suitable as a wound healing material for the treatment of deep wounds such as crush wounds, pressure ulcers, and leg ulcers. The present invention relates to a chitin web-like material having the following elasticity.

[0002]

2. Description of the Related Art Conventionally, chitin has an antibacterial action, a hemostatic action,
Various properties such as healing-promoting action, adsorption action, and plant growth-promoting action have been elucidated and used in a wide range of fields. The material used has various shapes such as powder, fiber, film, film, and cotton, and is used depending on the intended use. In particular, cotton-like chitin is considered to have many applications utilizing the above properties. For example, JP-A-4-370258 proposes to use chitin cotton as a wound protector, and it is described that good results can be obtained from its excellent exudate-eliminating effect and healing-promoting effect.

[0003]

However, since chitin cotton has high hydrophilicity in chitin itself, it is difficult to maintain elasticity in the presence of water, and since it is difficult to be crimped, elasticity is maintained for a long time even in a dry state. However, the use of cotton-like chitin has a limit.
An object of the present invention is to provide a chitin web-like material which is easier to use and has elasticity than the conventional chitin web-like material.

[0004]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventors have found that chitin and a mixture with a cotton-like material other than chitin can solve such a problem. The invention was reached. That is, the gist of the present invention is a chitin web-like material having elasticity, which is characterized by being mixed with cotton-like chitin and a cotton-like material other than chitin.

The present invention will be described in detail below. In the present invention, chitin refers to poly-N-acetyl-D-glucosamine and its derivatives obtained by treating the exoskeleton of crustaceans and insects with hydrochloric acid and caustic soda to remove ash and protein substances. Derivatives include deacetylated chitin and chitosan, and further salts formed with chitin and acids, such as acetate, hydrochloride, nitrate, phosphate, etc., and further -OH group or -CH ₂ OH of glucosamine residue. Chitin derivatives whose groups are modified by esterification, etherification, carboxymethylation, hydroxymethylation, or O-ethylation are also included.

Deacetylation of chitin in the case of using the deacetylated chitin in the present invention can be carried out by a known method of treating chitin with an alkali. At this time, the degree of deacetylation can be easily adjusted by appropriately changing the alkali concentration used, the treatment temperature, the treatment time and the like.

The deacetylation degree here means a value measured by the following method. About 2 g of the sample is put into 200 ml of a 2N-hydrochloric acid aqueous solution and stirred at room temperature for 30 minutes. Then, after filtering with a glass filter to remove the aqueous hydrochloric acid solution, the mixture was poured into 200 ml of methanol and mixed with 3 ml of water.
Stir for 0 minutes. This product is further filtered through a glass filter, put into 200 ml of fresh methanol, and stirred for 30 minutes. After repeating this washing operation with methanol four times, it was air-dried and vacuum-dried, and about 0.2 g thereof was precisely weighed, 100 ml was placed in an Erlenmeyer flask, 40 ml of ion-exchanged water was added, and the mixture was stirred for 30 minutes.
Then, this solution is subjected to neutralization titration with 0.1N-caustic soda aqueous solution using phenolphthalein as an indicator. Deacetylation degree (A) is calculated by the following equation.

[0008]

[Equation 1]

However, a is the weight of the sample (g), and f is 0.
The titer of 1N-caustic soda aqueous solution, b is the titer (ml) of 0.1N-caustic soda aqueous solution.

Cotton refers to the above chitin fiberized and entangled like cotton. The distinction between cotton and non-woven fabric usually means that the non-woven fabric is fixed between fibers with an adhesive or the like, whereas cotton is physically entangled by utilizing the entanglement of the fibers themselves.

The chitin fiber has a shape elongated in the longitudinal direction. Those obtained from nature which already have fibrous form can be used as they are. Further, a fibrillar substance prepared by dissolving chitin in a solvent and then coagulating with a coagulating liquid can be used as a fiber of chitin.

As the solvent, an appropriate solvent can be used depending on the kind of chitin or its derivative. For example, for chitin obtained by purifying a natural product and chitin having a relatively low degree of deacetylation, a mixture of a halogenated hydrocarbon and trichloroacetic acid, a mixture of N-methylpyrrolidone or dimethylacetamide and lithium chloride is preferably used. For chitin and chitosan having a high degree of deacetylation, an acid solution such as acetic acid is preferably used.

In forming the chitin into fibers, a conventional wet spinning method or wet forming method can be adopted. For example, chitin is dissolved in these solvents to form a dope, which is filtered through a filter such as a stainless net to remove undissolved components and foreign substances, and then transported and measured by a gear pump or the like, and water or alcohol is discharged from a nozzle having pores. Coagulates by extruding into a coagulating liquid such as ketones. The coagulated product is drawn at a constant speed by, for example, a rotating roller to form fibers.

The thickness of the fiber can be any ordinary one, but it is preferably about 0.3 to 10d, more preferably 0.5 to 5d, and particularly preferably 0.7 to 2d. The length is preferably 0.5 to 15 cm, more preferably 2 to 8 cm. To make a cotton-like material from the obtained fibers, any method may be used as long as the fibers are physically entangled.

For example, the fibers can be cut into a certain length and then passed through a defibrating machine such as a card machine to be made into a cotton shape. Further, in order to fix the entanglement, it may be processed by a known method such as treatment with a needle punch machine or entanglement with a water jet machine. If a crimping machine is used before processing by these methods, a good cotton-like material can be produced.

It is preferable to give the cotton-like material flexibility.
To that end, for example, the cotton wool of chitin is treated with a softener. As the softening agent, for example, an anionic surfactant, a nonionic surfactant, a higher alcohol-based anionic surfactant, a cationic surfactant, a silicone-based oil agent, a polyamine-based amphoteric surfactant and the like can be used.

Fibers other than chitin mean ordinary general-purpose fibers such as synthetic fibers and natural fibers. As synthetic fibers, polyester, acrylic, polyvinyl alcohol,
Polyamide, polyethylene, etc. are available, and natural fibers include cotton, wool, silk, linen, etc. Other than these, rayon and the like can be used.

As these fibers, those usually produced in the textile industry can be used. For example, one fiber having a thickness of about 0.3 to 20 d may be crimped and then cut into a certain length.

The mixture of cotton-like chitin and cotton-like substances other than chitin refers to a mixture of these chitin fibers and fibers other than chitin. The method of mixing is not particularly limited, and may be an ordinary method, for example, after mixing chitin fibers cut into short fibers and fibers other than chitin,
It can be created by the method of defibrating and confounding with a card machine. The mixing amount is usually determined depending on the field of application and application, but is usually 1 to 90%, preferably 5 to 80%, and more preferably 7 to 65% of the total weight of chitin fiber.

The thickness of the cotton-like material can be determined according to the purpose and is not particularly limited.
The amount is preferably 1.0 to 350 g / m ² , and more preferably 2.5 to 100 g / m ² . If the basis weight is smaller than this, there may be a problem in elasticity.

The chitin web-like material obtained as described above has the same therapeutic accelerating effect as when chitin alone is used for treatment, and maintains elasticity even when used for wounds with a large amount of exudate. Not only does it serve as a cushion, but also improves the overall feeling of use, including when replacing the cushion.

Further, the chitin web-like material of the present invention has sufficient properties as a structural material, and further has various activities of chitin such as specific adsorption, moisturizing property, physiological activity, antibacterial property, Since it has properties such as acoustic effect, it grows plants by biotechnology etc. as a part that roots the plant that can grow on cotton or sponge like radish and lawn. It can be used as a floor when making.

[0023]

EXAMPLES The present invention will be described in more detail below with reference to examples.

Example 1 and Comparative Example 1 Chitin powder was pulverized to 100 mesh and 1N-HCl was added.
At 4 ° C. for 1 hour, and further heat-treated in a 3% NaOH aqueous solution for 3 hours at 90 ° C. to remove calcium components and proteins contained in the chitin powder, and repeatedly wash with water to dry. The obtained chitin was dissolved in a dimethylacetamide solution containing 8% by weight of lithium chloride to a concentration of 0.2% by weight, and the viscosity of the solution was 2 at 30 ° C.
The value was 65 centipoise. This chitin was dissolved in a dimethylacetamide solution containing 7% by weight of lithium chloride so as to be 7% by weight. The obtained dope is filtered through a wire mesh of 1480 mesh, left to defoam, placed in a tank and transported by a gear pump under pressure, and discharged from a nozzle having a diameter of 0.06 mm and a 200 hole of 2.2.
It was extruded into a butanol solution at 60 ° C. at a rate of g / min to coagulate, and was taken up by a roller at a speed of 10 m / min. The obtained yarn was thoroughly washed with water and then dried to obtain a filament having a denier of 0.98 d and a strength of 3.1 g / d.

The filament obtained as described above was cut into 35 mm. 20 g of cotton-like chitin was prepared by immersing the obtained short fibers in a softening agent containing white petrolatum as a main component, drying it sufficiently, and applying the softening agent. On the other hand, single yarn denier 1.33d, strength 4.5g / d, cut length 35
20 g of mm polyester short fibers were prepared. These are mixed to make 40 g, and a card machine (manufactured by Daiwa Kiko Co.,
It was defibrated with SC-360) and wound on a drum with a diameter of 80 cm. The basis weight of the obtained mixed web-like material is 22.4 g / m.
² (Example 1).

For comparison, 40 g of the cotton-like chitin obtained by the above method was defibrated by the above card machine without mixing polyester short fibers, and wound on a drum having a diameter of 80 cm. The weight of the obtained web-like material was 20.1 g / m ² (Comparative Example 1).

The flexural rigidity of the above two kinds of web-like materials and the flexural rigidity in case of breakage were measured and compared. Bending rigidity is one of the indexes showing the feeling of use of the web, and the larger the value, the better the feeling of use. The bending stiffness was measured with a KES-F2 pure bending tester. In the KES system, the bending rigidity is defined as the slope between the curvatures K = 0.5 and 1.5 (cm ^-1 ). However, if the curvature K is 1.5 or less and bending occurs, K = 0 to It is represented by the slope until it breaks.
The results obtained by the above measuring method are shown in Table 1 below. As is clear from Table 1, Example 1 showed higher values in both the vertical and horizontal directions than Comparative Example 1, and the result was that Example 1 had a better usability.

[0028]

[Table 1]

Next, two skin full-thickness wounds were created on the back of the rabbit, and one wound was treated using the mixed web-like material obtained in Example 1. As a method of use, a sufficient amount of web-like material was filled in the defective wound, and the wound was covered with gauze and fixed with skin tape. The web was changed once a week. For comparison, the other defective wound was filled with the chitin-only web obtained in Comparative Example 1 and treated in the same manner as the mixed web. When treated with the mixed web of Comparative Example 1, the formation of granulation on the wound surface was good, but immediately after use, the exudate lost elasticity and did not show a sufficient exudate removal effect. The mixed web of Example 1 absorbed the exudates very well and was able to lead the wound surface to a dry state at all times. The generation of clear granulation was observed from about 1 week after the start of treatment, and the wound was completely closed at 3 weeks. Although polyester did not have a healing effect on the wound, the web-like material composed of cotton-like chitin and polyester showed a healing effect more than expected when the web-like material containing chitin alone was used.

Example 2 Chitosan (manufactured by Kyowa Yushi Co., Ltd., deacetylation degree = 90.2%) having a viscosity of 32 centipoise at 20 ° C. when dissolved in a 0.2M acetic acid aqueous solution at 0.2% by weight has a concentration of 6% by weight
Was dissolved in a 0.2 M acetic acid aqueous solution so that the resulting solution was filtered through a 1480 mesh stainless net to obtain a viscous solution. This solution was sent by a gear pump, discharged from a nozzle having a diameter of 0.06 mm and 100 holes into a 1N-caustic soda aqueous solution, which is a coagulating solution, at a rate of 1.9 g / min to perform primary coagulation, and then again. The mixture was solidified with a 1N-caustic soda aqueous solution for about 1 hour, subsequently neutralized and washed with dilute hydrochloric acid, and then dried. The obtained yarn had a single yarn denier of 0.88 d and a strength of 3.5 g / d. 4 this yarn
A cotton-like chitosan was prepared in the same manner as in Example 1 by cutting it into 5 mm and taking 20 g. The basis weight of the obtained cotton-like chitosan web-like product was 19.2 g / m ² .

On the other hand, single yarn denier 1.02d, strength 2.
Prepare 20g rayon with 3g / d and cut length 45mm,
A cotton-like material was prepared by defibrating with a defibrating machine in the same manner as in Example 1. The weight of the obtained cotton-like rayon web-like material is 2
It was 1.9 g / m ² . Next, the cotton-like chitosan web-like material and the cotton-like rayon web-like material are stacked on top of ^each other and entangled with a needle punch machine (manufactured by Daiwa Kiko Co., Ltd., NL-380) at a rate of 40 needles / cm ² , and chitosan rayon. A web of a cotton-like mixture was prepared. The weight of the chitosan rayon web was 36.7 g / cm ² .

This web-like material was sterilized with ethylene oxide gas and used to treat a 78-year-old male patient who had a pressure ulcer on the sacral region. The size of the pressure ulcer reached the fascia in depth, and the size was an ellipse with a length of about 5 cm and a width of about 6 cm. The necrotic tissue around the affected area was excised with a scalpel and then thoroughly washed with physiological saline. Further, an isodine solution was applied and then a chitosan rayon web material was filled. The web-like material adhered well to the affected area, but it was further fixed with gauze and skin tape. The wound on the second day did not retain the exudate due to the exudate removing effect of the web-like material, and the web-like material kept the wound in a wet state and adhered well. When the chitosan rayon web was treated by changing it every two days, the wound gradually became smaller and completely healed after two months. In the final stage of the treatment, it was replaced every week.

Example 3, Comparative Example 2, Comparative Example 3 8 g of the chitosan short fiber (cut length 45 mm) obtained in Example 2 was prepared, while single yarn denier 0.81 denier, strength 4.6 g / d, cut One 45 mm long nylon short fiber
92 g was prepared and the above two kinds of fibers were uniformly mixed. A mixed web-like material was prepared in the same manner as in Example 1. The weight of the formed web-like material was 104 g / m ² . This web-like material was cut into an appropriate size, put in a petri dish, and an appropriate amount of water was added to grow the radish sprouts on the web-like material (Example 3). For comparison, a group was used in which the web-like material used above was made from only nylon short fibers (Comparative Example 2), and a group using a web-like material made from only chitosan short fibers was made (Comparative Example 3). The same experiment was conducted. In all groups, germination occurred 1 day after sowing. All grew well, but the growth rate was higher in Example 3 and Comparative Example 3 than in Comparative Example 2 due to the plant growth promoting effect of chitosan. However, in Comparative Example 3, the elasticity and volume of the web-shaped material decreased when water was added, and it collapsed due to its own weight 7 days after germination. In Example 3, due to the elasticity of the nylon web, it was possible to maintain a sufficient space for roots to grow, it was possible to absorb water well, and the effect of the growth promoting effect of chitosan resulted in unexpectedly good results.

Example 4 and Comparative Example 4 20 g of the chitosan short fiber obtained in Example 2 was prepared, and 90 g of nylon short fiber having a single yarn denier of 0.34 denier, a strength of 5.1 g / d and a cut length of 35 mm was prepared. Then, these were well mixed to prepare a mixed web-like material by the method of Example 1. The weight of the web-like material was 107 g / m ² .
When this is used for the insole of shoes, it absorbs odor well due to the deodorant antibacterial property of chitosan and suppresses bacterial growth in shoes,
In addition, the elasticity of the nylon web has the effect of reducing fatigue. For comparison, the above-mentioned webs of chitosan and nylon were separately prepared and stacked to form an insole (Comparative Example 4). When Chitosan web was placed on the bottom and nylon web was placed on the top, bacterial growth in the shoes could be prevented to some extent, but the deodorant effect was lacking because it was not in direct contact with the foot. On the contrary, when the chitosan web was placed on top and the nylon web was placed on the bottom, the chitosan web was in direct contact with the foot, so that the deodorizing effect was exhibited well, but bacterial growth in the shoes could not be prevented. As described above, Example 4 exerted an excellent effect due to the two synergistic effects as compared with Comparative Example.

Example 5, Comparative Example 5 The mixed web-like material obtained in Example 4 was used as an air cleaning filter. Chitosan, which is also known as an adsorbent, absorbs harmful substances in the air well, but because it forms a structure with nylon as a support, the apparent volume of chitosan increases, and the expected adsorption of chitosan. The removal effect was more than the amount. For comparison, a filter containing only chitosan was prepared and the same experiment was conducted to measure the weight of the substance adsorbed on the filter. As shown below, the mixed web exhibited an unexpectedly superior effect. Here, after continuous operation in the same room for 30 days, the amount of adsorption per unit area of the filter was measured.

[0036]

[Table 2]

Example 6 1 kg of the chitosan short fiber obtained in Example 2 was prepared, and 3.5 kg of nylon short fiber having a single yarn denier of 1.25 denier, a strength of 5.1 g / d and a cut length of 50 mm was prepared. These were mixed well and a mixed web-like material was prepared by the method of Example 1. The weight of the web-like material was 2.7 kg / m ² . This was used as futon cotton. The futon cotton has elasticity which is an advantage of the nylon web, and moisture absorption / exhaustion and antibacterial deodorization which are advantages of chitosan.

[0038]

Since the web-like material of the present invention contains the cotton-like material other than chitin, it has elasticity as well as the original characteristics of chitin and is easy to use. Especially in the medical field, when used as a wound covering protective material for skin damage such as burns, skin-collecting wounds, and skin-grafting wounds, it is excellent in adhesion to the affected area, melting resistance by exudate, and exudate removal effect. In addition, it does not damage the affected part during use and is in a good healing state, and is particularly effective as a protective material for deep wounds such as pressure ulcers.
Further, it can be used in the fields of agriculture, clothing and other fields.

Front page continuation (72) Inventor Nobuyuki Tanimoto 23 Uji Kozakura, Uji City, Kyoto Prefecture Unitika Ltd. Central Research Laboratory

Claims (1)

[Claims] 1. A chitin web-like material having elasticity, comprising a mixture of cotton-like chitin and a cotton-like material other than chitin.