JPS596060A - Fixing material for orthopedics - 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] FIELD OF THE INVENTION The present invention relates to orthopedic fixation materials.

BACKGROUND OF THE INVENTION It has been known to use plaster bandages as fixing materials for orthopedics such as plaster casts, splints, ball-shaped casts, and training prosthetics. Although these plaster bandages are effective enough to immobilize the affected area and protect against external impact, they are very heavy, have little air permeability, and, once hardened, can be rapidly removed in damp conditions, e.g., when in contact with water. It has disadvantages such as losing strength and becoming brittle.

Furthermore, it is difficult to take X-rays while the patient is wearing a cast, and the plaster cast must be removed in order to diagnose the state of healing of the affected area, which is very inconvenient for both doctors and patients. In recent years, fixing materials for orthopedics that replace plaster bandages have been developed, such as those using polymer compositions with a heat softening point and those using ultraviolet curable resin compositions, but the former usually has a softening temperature of about 80°. It has a high temperature of C and lacks flexibility, so it does not fit the body sufficiently and is difficult to tuck.

The latter uses an ultraviolet curable resin composition and requires an ultraviolet irradiation device, which is expensive and difficult to handle, and furthermore, the ultraviolet rays only reach the upper layer of the bandage made of ultraviolet curable resin. It has the disadvantage that it takes a long time to harden to the inside.

Unexamined Japanese Patent Publication No. 5, 1987 as a fixing material for orthopedic surgery that improved these drawbacks.
There is a bandage impregnated with incyanate prepolymer described in No. 3-61184. In this case, if there are many -NCO groups in the isocyanate prepolymer, the curing speed becomes faster, which limits the shaping and fixing time, and the exothermic reaction with water causes an abnormally high temperature, which causes serious problems such as skin burns.

On the other hand, if the incyanate prepolymer has a small amount of -NGO groups, the problem of burns will not occur, but the curing speed will be slow and the suitability for fixing time for cast shaping will be impaired. Therefore, as a fixation material for cast surgery, it satisfies the extremely limited conditions that the maximum heat generation temperature during fixation does not rise above the skin temperature, and the fixation is completed within 5 to 10 minutes. It is required to be a fixation material for orthopedics.

On the other hand, the supporting base material constituting the orthopedic fixing material is woven fabric or silk cloth, mainly coarse thin gauze fabric, but when using these normal supporting materials, in order to obtain sufficient strength during fixation, It is necessary to apply a large amount of bandage,
Extremely sophisticated techniques are required to obtain uniform strength throughout the cast.

In view of the above drawbacks, the present inventors have developed a product that is lightweight, highly breathable, easy to take X-rays when worn, and has good elasticity in the latitudinal direction when fixed for orthopedic surgery, and has a good fit to the limb. The present invention was achieved through research in order to obtain a fixing material for shaping that can easily provide an average strength to the entire cast, suppress heat generation during shaping and fixation, and allow shaping and fixing within a predetermined time.

The present invention is a resin whose main component is a polymer containing isocyanate groups and/or blocked isocyanate groups in the molecule, and in which the inocyanate groups and/or blocked isocyanate groups in the composition are contained in an amount of 10 to 17% by weight. The fixing material for shaping consists of a warp-knitted fabric with hydrophobic attached fibers to which a composition is adhered in an amount of 50 to 300%.

Polymers having one=NGO group in the molecule used in the present invention include, for example, polymer compounds having active hydrogen in the molecule such as polyester polyols, polyester polyols, polyamines, and polyhydric alcohols, and hexamethylene diisocyanate. , tolylene diisocyanate, xylene diisocyanate), 4,4-diphenylmethane diisocyanate), 1,5-naphthalene diisocyanate, and mixtures thereof. Any greborimer having -NCO group is sufficient, and the viscosity is 5,000 to 60,000 OO at 25°C.
Preferably it is a viscous liquid that is CpS. Furthermore, using a polymer containing blocked isocyanate groups instead of isocyanate groups is very effective in increasing the stability of iso7anate.

The blocking agent for incyanate is preferably a tertiary alcohol, lactam, ethanol, etc., in view of the toxicity of the component when it is once dissociated.

Similarly, these polymers containing blocked isocyanate groups in their molecules have a viscosity of 5,000 to 60.0 at 25°C.
Preferably, it is a viscous liquid of 0.00 cps.

These polymers having -NCO groups in their molecules and polymers containing blocked in cyanate groups in their molecules are
-=German, or can be used in combination.

In addition, by adding a low-viscosity isocyanate compound having two or more -NCO groups in the molecule to the above-mentioned combination, it is not only possible to adjust the viscosity of the combination, but also to adjust the viscosity of the combination as appropriate. This selection is effective in that it is possible to select the crosslinked structure in the resin to be produced, and it is also possible to control the strength of the product.

Such isocyanate compounds include, for example, hexyxadiisocyanate, 4,4'-diphenylmethane diisocyanate, quizylene diinocyanate, and the like.

In this case, the amount of -NCO groups and/or blocked isocyanate groups in the constituent molecules of the resin composition must be controlled within the range of 10 to 17% by weight.

If the amount of the functional group exceeds 17% by weight, the curing speed with water increases and heat is generated (more likely to cause burns).

Conversely, if the amount of functional groups is less than 10% by weight, a problem arises in that the curing time is too long.

If the viscosity of the resin composition is 5,000 cps, the adhesion during shaping will be poor, and the fit will likely be inadequate.
This lowers interlayer adhesion and makes it difficult to obtain sufficient strength.

On the other hand, if the viscosity exceeds 60,000 cps, the tackiness will be too great and shaping operations will become difficult.

On the other hand, the resin composition is 50 to 300% owf on silk fabric.
It is necessary to attach it within the range of .

If the amount of the resin composition deposited is 50% ow, the interlayer adhesion will be reduced and sufficient strength will not be obtained. On the other hand, if the amount of adhesion exceeds 300% owf, it becomes extremely difficult to handle and loses its suitability as a fixing material for orthopedic surgery.

The resin composition 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 XIN permeability, product pot life, etc.

The proportion of the polymer in the resin composition is 10% by weight or more, preferably 30% by weight or more in view of the performance of the final product; if it is less than that, it becomes difficult to impart durability to the molded product.

Since the resin composition of the present invention has a specific gravity after curing similar to that of proteins constituting the human body, it has high transparency to X-rays.

The hydrophobic synthetic fiber knitted fabric used in the present invention has a basis weight of 50 to 3.
00t/n? It is preferable that

Is the basis weight 50f/r1? If it is less than that, it will be difficult to sufficiently adhere the resin liquid, and it will be necessary to wrap the resin in a large amount in order to obtain sufficient strength during fixing. Also, the basis weight is 300
If it exceeds 9/m'', even if a sufficient adhesion amount is obtained, the deformability as a fixing material will be poor and the shiftability will be reduced.

On the other hand, the warp elongation of synthetic fiber knitted fabric is less than 1°, and the weft elongation is 2
It is preferably 0 to 150%.

If the warp elongation is 10% or more, the workability and shapeability will be insufficient, and if the weft elongation is less than 20 inches, the fit will be poor.
It is difficult to obtain sufficient strength during fixing because it reduces interlayer adhesion during fixing.

Furthermore, if the elongation exceeds 150%, processability tends to be poor, causing spots of resin liquid adhesion, and at the same time making it difficult to use.

The fibers constituting the hydrophobic synthetic fiber knitted fabric used in the present invention are preferably polyolefin synthetic fibers with a water absorption rate of 0.1% or less. The water absorption rate here refers to the official moisture content, and specifically includes polypropylene fibers and polyethylene fibers. When synthetic fibers with a water absorption rate exceeding 0.1 inch are used, the resin composition used in the present invention easily reacts with water, so it may not be contained in the fibers during the storage period until it is used as a fixing material for orthopedics. The moisture contained in the resin composition reacts with the resin composition, which tends to cause problems such as the reaction progressing and curing before actual use.

Further, as the hydrophobic synthetic fiber knitted fabric used in the present invention, a warp knitted fabric is preferably used.

The size of the warp knitted fabric is not particularly limited, but from the viewpoint of ease of use, the width is preferably 5 crn to 30 crn1, and preferably 10 to 20 crn.
A crn1 having a length of 2 m to 5 m, preferably 3 m to 4 m is used.

When a warp knitted fabric having a warp elongation of 10% or less is used, it is extremely easy to handle without causing problems such as selvage even when stretched during processing or use.

Since the orthopedic fixing material according to the present invention easily reacts with water and hardens, it is preferably stored in a sealed container with moisture removed while being wrapped around the outer periphery of a hydrophobic rod.

As the hydrophobic rod-shaped body, a polyolefin resin rod-shaped body having a water absorption rate of 0.i% or less is preferably used, and specifically, it is preferably made of polypropylene resin or polyethylene resin.

The rod-shaped body may be a solid body, a hollow body, or a tubular body.

Preferably, the fixing material for shaping of the present invention is wound around the outer periphery of a rod-shaped body made of polypropylene resin, placed in a sealed bag made of polyethylene 711L aluminum foil or aluminum vapor-deposited film, and stored until use.

The orthopedic fixing material stored in the closed container is taken out at the time of use and immersed in water or hot water, preferably hot water at 20-35°C, preferably for a soaking time of no more than 1 minute. After soaking, the mixture is squeezed out and used to cover affected areas such as limbs, depending on the purpose.

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 half of the weight of plaster bandages, which are extremely lightweight. Furthermore, since foaming occurs when reacting with water,
Provides breathability.

In addition, the shaped article obtained by reaction curing contains crosslinks 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) It is lightweight.

(2) Good X-ray transparency.

(3) It is a flexible material and has excellent fit and ease of tack removal.

(4) Treatments similar to those of conventional plaster bandages can be performed.

(5) Appropriate curing time.

(6) Breathable.

(7) It is durable.

In addition, the warp elongation and weft elongation of the knitted fabric were measured using a width of 5 Crn.
The load elongation curve was measured using a Tensilon using a sample with a length of 10 Crn, and the elongation under a load of 200 t/tm was calculated using the following formula.

Next, specific examples of the present invention will be explained with reference to the drawings.

FIG. 1 is a partially cutaway perspective view showing an example of the storage form of the orthopedic fixing material of the present invention.

A polypropylene resin hollow tubular body (1) with a viscosity of 52,000c containing 12% by weight of -NCO groups in the molecule.
PS (25°C) resin liquid mainly composed of polymer is adhered 100% owf to polypropylene fiber warp knitted fabric with basis weight 801/rd warp elongation 6 inches, weft elongation 60 inches, width 10α. A rod-shaped object made of silk fabric (2) is wrapped inside a sealed container (3) made of aluminum-deposited polyester film, and a part of the sealed container (3) is cut out to open it.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway perspective view showing an example of the orthopedic fixing material of the present invention. (1) Hydrophobic hollow tubular body. (2) A hydrophobic synthetic fiber warp-knitted fabric to which a resin composition whose main component is a polymer having -NCO groups in its molecules is attached. (3) Closed storage. that's all

Claims (6)

[Claims] (1) The main component is a polymer containing an isocyanate group and/or a blocked isocyanate group in the molecule,
Fixing for shaping consisting of a hydrophobic synthetic fiber warp-knitted fabric to which a resin composition containing 10 to 17% by weight of isocyanate groups and/or pro-Tsukugermancyanate groups in the composition is adhered at 50 to 300% owf. material. (2) The viscosity of the resin composition measured at 25°C is 5.0
The orthopedic fixing material according to claim 1, characterized in that the fixing material has a cps of 00 to 60,000 cps. (3) Hydrophobic synthetic fiber warp knitted fabric has a basis weight of 50 to 3002/-
3. The fixing material for orthopedics according to claim 1 or 2, which is a knitted fabric having a longitudinal elongation of 10% or less and a weft elongation of 20 to 150 inches. (4) The fixing material for shaping according to claim 1, 2 or 3, wherein the hydrophobic synthetic fiber warp knitted fabric is made of polyolefin synthetic fiber. (5) A hydrophobic synthetic fiber warp knitted fabric is wound around the outer periphery of a hydrophobic rod-shaped body and is housed in a sealed storage body.Claims 1, 2, and 3 Fixing material for orthopedic surgery according to item 1 or 4. (6) The fixing material for orthopedic surgery according to claim 5, wherein the hydrophobic rod-shaped body is made of polyolefin resin.