JPH0559246A - Resin composition for cast material - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] When worn, it does not cause discomfort to the affected area, does not irritate the skin, has good breathability, and allows the drug to be added as needed, so the effect of the drug is A resin composition for a cast material shown on an affected part. [Structure] A composition containing at least one of hydroxy lower alkyl methacrylate and acrylamide as a main component and other methacrylate added thereto, or a composition obtained by adding a cyclic lactam to the composition is copolymerized,
A resin composition for Gibbs obtained by impregnating the obtained copolymer with water, wherein the ratio of the main component to the other methacrylates is 80:20 by weight or more, and the ratio of the cyclic lactam to the methacrylate is 30% or more by weight. Is. When Water is Impregnated By adding a drug to water, the drug is impregnated in the copolymer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel curable resin composition as a cast material, and more specifically, it is made of a hydrophilic resin and when contacted with water, the water rapidly penetrates into the interior and is soft. The present invention relates to a cast material that becomes a water-containing softening resin, is cured by drying for a suitable time, and has high strength and excellent air permeability after curing.

[0002]

2. Description of the Related Art Calcined gypsum has been widely used as a cast material. However, calcined gypsum is water-sensitive, so it is weak against water, heavy and bulky, weak in strength, and easily crushed.
It has many drawbacks such as irritation to the skin, impermeable to X-rays, fixing work requires some skill and time.

Gibbs materials using resins have recently been proposed as means for improving the drawbacks of these calcined gypsum. For example, a Gibbs material containing a photocurable resin-impregnated Gibbs material composed of an epoxy resin, an aluminum compound, and a silicon compound which produces a silanol group by irradiation with light is disclosed in JP-A-60-55957. However, a Gibbs material comprising a polyisoprene polymer, an ethylene vinyl acetate copolymer or a polyester resin and magnetic powder is disclosed in JP-A-1-175854.
It is disclosed in Japanese Patent Laid-Open No. 203260. However, since they have poor air permeability, it is necessary to heat them in advance in a thermoplastic resin, and in a photocurable resin or a water-curable resin, it is necessary to use a storage method that does not cure during storage of the material. It has drawbacks.

Further, Japanese Patent Publication No. 48-6116 discloses that
An orthopedic bandage in which an unsaturated polyester resin and a terminal ethylenically unsaturated monomer such as styrene and methyl methacrylate are used in combination is disclosed in Japanese Patent Publication No. 54-39675.
Surgical dressings using reaction products with hydroxyalkyl acrylates, polyisocyanates and polyhydric alcohols are disclosed. However, unsaturated polyester resins and acrylate resins have drawbacks such as high viscosity, unpleasant odor, large shrinkage upon curing, and skin irritation, and their use is limited.

In order to improve the defects of calcined gypsum in this way,
The proposed resin material also has difficulty in handling, skin irritation and the like, and also has drawbacks such as poor breathability. Since the living body is breathing through the skin, it is natural that a material having good breathability when worn is preferable.

[0006]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned drawbacks of conventional plaster of plaster and resin materials such as a plaster material, does not cause discomfort to the affected part at the time of wearing, does not irritate the skin, and has breathability An object of the present invention is to provide a good resin composition for Gibbs material. It is another object of the present invention to provide a resin composition for a cast material which further contains a drug and exhibits a medicinal effect on the affected area when the drug is worn.

[0007]

The resin composition for cast material of the present invention becomes very soft when impregnated with water. When the composition impregnated with water is attached to the affected area, the composition hardens to show high strength as the water evaporates, and the breathability is maintained. Depending on the conditions of use, it is possible to adjust the curing time and strength by impregnating water with alcohol and the like, and also by changing the components and composition ratio of the composition, the curing time,
It is possible to adjust the intensity. Further, anti-inflammatory agents, analgesics, anti-itch, coexistence of drugs such as bactericidal agent in water, to obtain a composition impregnated with these drugs, when the composition impregnated with such drugs is attached to the affected area, The drug is released from the composition during wearing, showing the advantage of giving each effect to the affected area.

The resin composition for cast material according to the present invention is
It is selected from the group consisting of copolymers of methacrylates and copolymers of methacrylates with cyclic lactams such as N-vinylpyrrolidone. Methacrylates used in the present invention include 2-hydroxyethyl methacrylate,
Optionally selected from hydroxy lower alkyl methacrylates such as hydroxypropyl methacrylate; lower alkylene glycol dimethacrylates such as ethylene glycol dimethacrylate; lower alkyl methacrylates such as methyl or ethyl methacrylate and methacrylamide (including acrylamide). It is particularly preferable to use a methacrylate having a hydrophilic group at the terminal such as hydroxy lower alkyl methacrylate and methacrylamide (including acrylamide).

Of the above-mentioned methacrylates, hydroxy lower alkyl methacrylate such as 2-hydroxyethyl methacrylate or methacrylamide is the main component, and other methacrylates are mixed with this, and a small amount of a catalyst is added if necessary. Then, it is polymerized by a conventional method to obtain a target copolymer of methacrylates. In this case, the mixing ratio of the methacrylate used as a product and the other methacrylate is not particularly limited, but it can be said that the larger the proportion of the main component used, the more preferable it is in consideration of water absorption. By weight, compared to 80:
It is 20 or more, preferably about 90:10.

As the cyclic lactam, N-vinylpyrrolidone is preferable. The formation of a copolymer of methacrylates and N-vinylpyrrolidone is carried out by mixing N-vinylpyrrolidone and any methacrylate selected from the above-mentioned methacrylates and, if necessary, a catalyst and polymerizing by a conventional method. A target methacrylate-N-vinylpyrrolidone copolymer is obtained. The amount of N-vinylpyrrolidone and the type of methacrylate used and their amount have a great influence on the water content of the resulting copolymer.
Generally, when the amount of N-vinylpyrrolidone is less than 30% by weight, the water content of the polymer is 20% or less and the flexibility of the polymer is lost. Therefore, the amount used is preferably 30% by weight or more.

The thus-obtained methacrylates or copolymers of N-vinylpyrrolidone and methacrylates are immersed in water to swell and then contain a predetermined amount of water to be used as a Gibbs material. If the water content is too high or too low, it is difficult to use as a cast material. That is, if the amount is too small, the flexibility is poor. Therefore, its content is 40-80
It can be obtained by adjusting the dipping time in water by setting about%. It is possible to impregnate the polymer with water by adding chemicals such as anti-inflammatory agent, analgesic, anti-itch, antiseptic, etc. to the polymer at the time of immersion in water. The effect is shown on the affected part. The seven kinds of chemicals to be added are not basically limited in the present invention, and any chemicals that can be dissolved in water and alcohols can be used, and examples thereof include menthol, fungal extract, methyl salicylate, thymol and camphor. The amount of addition depends on the drug used, but it can be generally said that addition of 50% by weight or less with respect to water is sufficient.

[0012]

Example 1 2-Hydroxyethyl metaacrylate 90
% By weight, 10% by weight of methyl metaacrylate, and 0.08% by weight of azobisisobutyronitilyl monomer are mixed and stirred,
The mixed monomer was dispensed into two glass plates fixed to a thickness of 0.2 mm, placed in a thermostat set at 60 ° C. and polymerized for 24 hours. The copolymer was then swollen with water for 4 hours. The water content of this copolymer was 43%, and it was flexible and good results were obtained in the mounting test. The oxygen permeability coefficient was about 20 × 10 ⁻¹¹ ml · cm / cm ² · sec · mmHg, and the hardness was Vickers hardness of about 14.

[0013]

Example 2 50% by weight of acrylamide, 40% by weight of 2-hydroxyethyl methacrylate, 10% by weight of methyl methacrylate and 0.08% by weight of azobisisobutyronitrile were mixed and stirred to form a mixed monomer. The mixture was dispensed into two glass plates fixed to a thickness of 0.15 mm, placed in a constant temperature bath set at 60 ° C. and polymerized for 16 hours. Next, this copolymer was mixed with menthol and camphor at 10% by weight, respectively.
Each of them was swollen with water containing 20% by weight of dissolved ethanol for 2 hours. The water content of this copolymer is 55%,
It was quite flexible and breathable, and good results were obtained in the mounting test. Oxygen permeability coefficient is about 25 × 10 ^-11 ml
・ Cm / cm ²・ sec ・ mmHg, hardness is Vickers hardness about 10
Met.

[0014]

Example 3 N-vinylpyrrolidone 70% by weight, methyl methacrylate 10% by weight, 2-hydroxyethyl methacrylate 10% by weight, ethylene glycol dimethacrylate 10% by weight, azobisisobutyronitrile 0.13.
Mix and stir the monomer of weight% to mix the mixed monomer into the glass plate 2.
It was dispensed into a sheet fixed to a thickness of 0.10 mm, placed in a thermostat set at 45 ° C., and polymerized for 24 hours. The copolymer was then swollen with water for 2 hours. The water content of this copolymer was 70%, and it was quite flexible and breathable, and good results were obtained in the mounting test. The oxygen permeability coefficient was about 32 × 10 ⁻¹¹ ml · cm / cm ² · sec · mmHg, and the hardness was about 10 Vickers hardness.

[0015]

The cast resin composition according to the present invention is
Hydroxyl lower alkyl methacrylate, methacrylamide (acrylamide) or cyclic lactam as the main component, and the copolymer obtained by adding methacrylate to this polymer and impregnated with water, it has been conventionally used as a Gibbs material. Compared with other resin compositions, it has less skin irritation, and oxygen permeation has good flexibility. Therefore, it is an excellent cast material because it is easy to wear as a cast material, has excellent breathability at the time of wearing, and various chemicals are added as necessary to give the drug effect to the affected part.

Claims (5)

[Claims] 1. A resin composition for Gibbs material, characterized in that a copolymer obtained by copolymerizing at least one of hydroxy lower alkyl methacrylate and acrylamide and another methacrylate is impregnated with water. 2. The resin composition for Gibbs material according to claim 1, wherein the hydroxy lower alkyl methacrylate and acrylamide are 80:20 or more in weight relative to other methacrylates. 3. The resin composition for Gibbs material according to claim 1, further comprising a cyclic lactam copolymerized. 4. The resin composition for Gibbs material according to claim 3, wherein the amount of the cyclic lactam is 30% or more by weight with respect to the amount of methacrylate. 5. The resin composition for a cast material according to claim 1, further comprising a drug.