JPS607724Y2 - Fixing material for orthopedics - Google Patents

Description

[Detailed explanation of the idea] , The present invention relates to a fixing material for orthopedics.

BACKGROUND ART Gypsum bandages have been widely used as fixing materials for orthopedics such as plaster casts, splints, casting casts, and training prostheses.

Casts, training prostheses, etc. made from these plaster bandages are sufficiently effective for immobilizing the affected area and protecting against external impacts, but they are very heavy, do not have sufficient ventilation, and are more susceptible to moisture such as water. Not only do they have various drawbacks, such as rapidly losing strength and becoming brittle when exposed to moisture, but they also make it difficult to take X-rays while wearing a cast, causing inconvenience in medical treatment.

Furthermore, when fixing using a plaster bandage, a large amount of water is required to dirty the treatment room.

In recent years, orthopedic fixing materials have begun to be developed to replace plaster bandages.

For example, some products use polymer compositions that have a thermal softening point, but they have drawbacks such as the softening temperature is as high as about 80°C, and because they lack flexibility, they do not fit well to limbs and are difficult to tuck. are doing.

Here, tuck refers to folding while removing folds when wrapping a fixing material for shaping around a limb or the like.

There are also bandages that use UV-curable resins that harden under exposure to UV rays, but they require UV irradiation equipment, which increases costs and makes the equipment difficult to handle. It has the disadvantage that it only reaches the upper layer of the film and takes a considerable amount of time to harden to the inside.

As a fixation bandage material that eliminates these drawbacks, JP-A-5
There is a bandage impregnated with an isocyanate prepolymer described in No. 3-61184.

On the other hand, woven or knitted fabric, mainly coarse gauze fabric, is used as the supporting base material constituting the fixing material for shaping, but when gauze fabric with a large porosity is used as the supporting base material,
The adhesion rate of the resin liquid is up to 300% by weight, which results in insufficient interlayer adhesion during fixation, and it is necessary to wrap a considerably large amount of bandage in order to increase the strength.

On the other hand, when a woven fabric, woven fabric, or non-woven fabric with a low porosity is used as a supporting base material, the basis weight of the supporting base fabric increases, the resin adhesion rate tends to decrease, and the fit to the limb etc. tends to decrease. As a result, it is inferior in ease of tack removal, making it unsatisfactory as a fixed bandage.

In view of the above-mentioned drawbacks, the inventors of the present invention have studied to obtain a fixation material for dissolution that is light, easy to take X-rays, fits well to the limb during use, has good air permeability, and is easy to remove tack. Then, we arrived at this idea.

This invention is made of synthetic fibers with a pore size of 0.2 ra or more, a porosity of 30% or more, and a water absorption rate of 5% or less.
Nonwoven fabric A of 0g/77f or less contains a polymer having -NGO groups in the molecule or -N in the molecule that hardens by reacting with water.
This is a fixing material for orthopedic surgery to which at least 300% by weight of resin B containing a polymer that expresses a GO group is attached.

The resin B used in the orthopedic fixing material of the present invention is 300% by weight or more, especially 400 to 80% by weight, based on the nonwoven fabric A that is the supporting base material.
00% by weight is preferable.

A supporting base material that is flexible, can fit well into any part of the limb, is easy to tack, and can contain a resin adhesion rate of 30% or more has a pore diameter of 0.2.
It must be a nonwoven fabric with a porosity of 30% or more and a porosity of 30% or more.

The pores referred to in the present invention include not only pores that completely penetrate the nonwoven fabric in the thickness direction, but also a large number of regularly arranged pore-shaped portions where the fiber density is extremely low compared to other portions. The hole does not necessarily have to be a perfect circle and may be oval, square, etc., but if the hole is oval, for example, the hole flO,2
rrvyt or more refers to the minor axis of the ellipse.

If the pore diameter is smaller than 0.2 mm, the deformability of the nonwoven fabric will be extremely poor no matter how large the pore size is, and the fit of the orthopedic fixing material to the limb will be poor.

Also, even if the pore diameter is 0.27 rfIL or more, the open area ratio is 30%.
If it is smaller, the fit is similarly poor and it is difficult to tack.

Furthermore, even if the pore diameter is 0.2 mm or more and the porosity is 30% or more, the resin adhesion rate is 30% in woven or knitted fabrics.
At the same time, it is difficult to increase the amount of saliva above 30%.
Even if the above resin could be attached, it would be difficult to remove the tack and the fit would be poor.

The fibers constituting nonwoven fabric A used in this invention have a water absorption rate of 5%.
Below, preferably 2% or less of synthetic fiber is used.

The water absorption rate here refers to the official moisture content, and specific examples include fibers such as polyester, acrylic, polyurethane, and polypropylene.

The nonwoven fabric has a date of 300 g/d or less, preferably 30 to
It is optimal to use one with a weight of 150 g/d in terms of product performance and ease of use.

When synthetic fibers with a water absorption rate higher than 5% are used, the resin B used in the present invention easily reacts with water, so the amount of moisture contained in the fibers during the storage period before use as a fixing material for orthopedic surgery is reduced. This tends to cause problems such as reaction between the resin B and the resin B, and the reaction ends and the resin B is cured before actual use.

As a means to obtain a perforated nonwoven fabric, for example, a nonwoven web is laminated on a large number of perforated plates, and several kg/cfl is applied from the top.
Although the entangling treatment method is complicated by the pressure of the needle-shaped water flow, the porosity and area weight specified in this invention are determined by controlling the laminated amount of the web, the porosity of the perforated plate, and the pressure of the needle-shaped water flow. It can be obtained by

The polymers having -NGO groups in the molecule used in the present invention include, for example, polymer compounds having active hydrogen in the molecule such as polyether polyols, polyester polyols, polyamines, and polyhydric alcohols, hexamethylene diisocyanate, -NGO group in the molecule obtained by reacting with polyfunctional isocyanate such as tolylene diisocyanate, xylylene diisocyanate, 4,4'-diphenylmethane diisocyanate, and 1,5-naphthalene diisocyanate. Any prepolymer having a molecular weight of 200 to 10,000 is preferable.

A polymer that expresses an -NGO group in its molecule refers to a polymer that can temporarily protect the incyanato-reactive group of the polymer having a -NGO group in its molecule and regenerate incyanate during use. , is very effective in increasing the stability of incyanate.

Such an isocyanate regenerant must be able to easily regenerate isocyanate by heating, and from the viewpoint of the heating temperature and the toxicity of the regenerant components when dissociated by heating,
Preferably, one component of the isocyanate regenerant is a tertiary alcohol, lactam, enol, or the like.

It is also preferable that the polymer in which the -NCO group is expressed in the molecule is liquid and has a molecular weight of 200 to 10,000.

These polymers having -NGO groups in their molecules or polymers expressing -NGO groups in their molecules can be used alone or in combination, but in the present invention, it is particularly important that these polymers are hydrophilic. preferable.

Furthermore, if a low-viscosity isocyanate compound having two or more -NGO groups in the molecule is added to the above polymer, it will not only be possible to lower the viscosity of the polymer and improve workability, By appropriately selecting the incyanate compound, it becomes possible to select the crosslinked structure in the rawhide resin, and it becomes possible to control the strength of the product.

Examples of such isocyanate compounds include hexamethylene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate, and the like.

Resin B of the present invention is mainly composed of the above-mentioned polymer, but in addition to the above-mentioned isocyanate compound, additives such as pigments, fillers, catalysts, and surfactants may be added as necessary. You can also add

Such additives must be used in consideration of X-ray transparency, pot life of resin B, etc.

The proportion of the polymer in the resin B is at least 3% by weight, preferably at least 3% by weight, in view of the performance of the final product; if it is less than that, durability cannot be imparted to the molded product.

Resin B used in the orthopedic fixing material of the present invention has a specific gravity similar to that of proteins that make up the human body after curing.
Highly transparent to X-rays.

The resin B may be attached to the nonwoven fabric A, which is the supporting base material, by a conventional method, such as an impregnation method, a coating method,
By injection method etc.

The adhesion rate of the resin B to the nonwoven fabric is 30% or more, preferably 400 to 80%.

If the adhesion rate is less than 300%, the interlayer adhesion will be poor and brittle when molded.

In the present invention, when resin B is attached to nonwoven fabric A, the fixing material for shaping may be in a state in which resin B is attached to the entire surface of nonwoven fabric A and fills all the pores in nonwoven fabric A, or Although any state in which pores remain is possible, when actually used in a cast or the like, a fixing material for orthopedic surgery having pores is preferable in terms of flexibility, fit, etc.

The orthopedic fixing material according to the present invention easily reacts with water and hardens, so it is stored in a sealed container with moisture removed.

They are stored in a rolled or folded state in sealed bags or cans made of aluminum foil, for example, until use.

The orthopedic fixing material stored in a sealed container is taken out at the time of use and immersed in water or hot water, preferably hot water at 20'C to 40C, and the immersion time is determined by the curing time of resin B in the orthopedic fixing material. is fast, so it is preferable not to exceed ■ minutes.

After dipping, it is lightly squeezed and used to cover affected areas such as limbs, depending on the purpose.

In this case, in order to promote the reaction between -NGO groups and water,
It is also possible to add to the water or hot water a substance that makes the water alkaline, an isocyanate activator such as a tertiary amine.

In addition, in the case of a fixing material for orthopedic surgery using a polymer composition in which the -NGO group in the molecule is protected and the isocyanate regenerated product is used, it is heated before use to express the -NGO group in the molecule, and then Use by soaking in water or hot water.

In order for orthopedic products such as casts and prosthetic limbs formed in this way to exhibit the same supporting and fixing effect as orthopedic products obtained from plaster bandages, they only need to weigh about 40% of the weight of plaster, which is extremely lightweight.

Furthermore, the orthopedic fixing material of the present invention foams when it reacts with water, thereby imparting air permeability.

In addition, the shaped article obtained by reaction curing contains cross-linked bonds in the resin and has appropriate elasticity, so it is very stable against moisture or external impact.

As described above, the orthopedic fixing material according to the present invention has the following characteristics.

(1) Light weight, (2) Good X-ray transmittance, (3) Flexible material with excellent fit and ease of tack removal, (4) Can be treated in the same way as conventional plaster bandages. (5
) has a fast curing time; (6) provides breathability during use; and (7) is durable.

Hereinafter, the present invention will be explained in detail with reference to Examples.

Example 1 A nonwoven fabric A made of polyester fibers of 1.5 d x 51 mm and having sufficient strength of 44 y/d, a pore diameter of 0.25 mm, an open area ratio of 43%, and a water absorption rate of 0.3% was slit into 10 cm width AD. -195 (Polyether polyurethane prepolymer manufactured by Mitsui Nisso Tsurethane, NCO
A fixing material for shaping was obtained by adhering the resin B (group content: 13.4%) using a dip nip method so that the adhesion rate of the resin B was 45%.

The fixing material for shaping obtained at this time had holes here and there.

The above fixing material for shaping was wound into a roll, placed in a bag made of a laminate of polyester film-aluminum foil-polyethylene film, and stored tightly.

After three months, the above-mentioned fixing material for orthopedic surgery was removed from the airtight bag,
After soaking in water at 25℃ for about W seconds and squeezing it lightly, apply a net bandage Ortex (cotton bandage made by Tokyo Shock Research Institute) in advance.
Pipe diameter 58rIr is lower-wound! The above-mentioned water-treated fixing material for orthopedics was wrapped around a vinyl chloride resin elbow tube having a thickness of approximately 5 mm.

At this time, the bent portion of the elbow tube was easily tacked, and the fit was sufficient along the shape of the elbow tube.

For comparison, a nonwoven fabric made of the same polyester fiber as in Example 1, 45 f/d, pore size of 0.057 FEII, and water absorption of 0.3% was impregnated with AD-195 under the same conditions as in Example 1. When the same evaluation as in Example 1 was carried out using the fixing material, the tack at the bent portion of the elbow tube was difficult to remove, and the fit was insufficient, resulting in a partially floating state.

In addition, the same evaluation as in Example 1 was conducted for commercially available gypsum bandages.

From the above evaluations, it was found that the fixing material for orthopedic surgery of the present invention was the lightest, had the best air permeability, and had a bending hardness comparable to or higher than when plaster was used.

Furthermore, it had excellent X-ray transparency.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway perspective view showing an example of the orthopedic fixing material of the present invention. Moreover, FIG. 2 is a model diagram of an embodiment of the fixing material for shaping in a state in which the resin B is not adhered to the entire surface of the nonwoven fabric A and some pores of the nonwoven fabric A remain. In the figure, A indicates the nonwoven fabric A, B indicates the resin B, and C indicates the pores C of the nonwoven fabric.

Claims (1)

[Scope of utility model registration request] Date 300f made of threatening fibers with a pore diameter of 0.2 rran or more, a porosity of 30% or more, and a water absorption rate of 5% or less.
//7y1″ or less nonwoven fabric A contains a polymer having -NGO groups in the molecule or -N in the molecule that hardens by reacting with water.
A fixing material for orthopedics, to which at least 30% of resin B containing a polymer that expresses a GO group is attached.