JPH01175856A - Surgical multi-filament seaming thread - Google Patents

Abstract

PURPOSE:To obtain a surgical multi-filament seaming thread, having suitable hardness with an excellent slipping quality in the time of operation, by coating the periphery of a seaming thread, formed by a multi-filament, with a polycaprolactin polymer of specific relative viscosity further a surface of the polymer with a polycaprolactin polymer of specific relative viscosity. CONSTITUTION:A multi-filament seaming thread is coated with two kinds of polycaprolactin polymers of different molecular weight. For providing suitable hardness, the first layer is coated with the polycaprolactin polymer of 1.5-3.2 relative viscosity, further for giving a good knot down characteristic, the second layer is coated with the polycaprolactin polymer of viscosity less than 1.3-1.5. The polycaprolactin polymer, from low molecular weight to high molecular weight, has a particular quality of slipping a thread, but when the relative viscosity is less than 1.3-1.5, the slipping effect is excellent but with a poor hardness giving effect, and by using the polycaprolactin of 1.5-3.2 relative viscosity for the first layer, suitable hardness is given to the multi-filament.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a surgical suture, and more particularly to a surgical multifilament suture having appropriate hardness and excellent slipperiness during operation. .

(Prior Art) As is well known, multifilament sutures in the form of braided or twisted threads for surgical purposes are more flexible than monofilaments, have a lower bending elastic modulus, and have less resistance to repeated bending. However, since the surface lacks smoothness, surface coating treatment is required. This coating process helps improve tissue passage and safely adjust the number of knots, but if the coating agent is non-bioabsorbable, there is a risk that the coating agent peeled off from the surface of the thread may diffuse into the body as foreign matter. Therefore, careful consideration must be given to the material of the coating agent. In recent years, it has been discovered that polycaprolactone polymers have excellent bioabsorbability.
As seen in Publication No. 2 and Japanese Unexamined Patent Publication No. 62-60557, multifilaments with an average molecular weight of about 15,00
Polycaprolactone polymers have been proposed for coating sutures or multifilament sutures coated with high molecular weight polycaprolactone polymers of 0 and about 40,000.

(Problems to be Solved by the Invention) However, a multifilament suture coated with a high molecular weight polycaprolactone polymer having the above-mentioned molecular weight has improved surface roughness of the multifilament and has a high ability to pass through tissue. This also has the added advantage of improving knot retention, especially the so-called ``tie-down'' performance of moving the knot downward to a predetermined location along the suture thread, but it also has the added advantage of improving the ability to tie the knot downward to a predetermined location along the suture. In order to accurately position the suture in a predetermined position and direction, a certain degree of rigidity, such as monofilament suture, is required.
That is, appropriate hardness is required, and the above-mentioned covered sutures have not yet been fully satisfactory in this respect.

The present invention has been made with the object of providing a multifilament suture that has an appropriate degree of hardness without sacrificing the advantages of a covered suture.

(Means for Solving the Problems) The multifilament suture according to the present invention is coated with two types of polycaprolactone polymers having different molecular weights, and the first layer (inner layer) has an appropriate hardness. In order to achieve this, it is coated with a polycaprolactone polymer with a relative viscosity of 1.5 to 8.2, and a second layer (surface layer) with a relative viscosity of It is characterized by being coated with a polycaprolactone polymer having a molecular weight of less than 1.3 to 1.5.

All polycaprolactone polymers, ranging from low molecular weight to high molecular weight, have the property of making threads slip, but when the relative viscosity is between 1.3 and less than 1°6, the slipping effect is excellent. However, the hardness imparting effect is poor and it is not possible to impart appropriate hardness to flexible multifilaments. By using coalescence, appropriate hardness is imparted to the multifilament f.

The thermoplastic polycaprolactone polymer used in the suture of the present invention is produced as follows.

That is, it is obtained by ring-opening addition polymerization of a lactone monomer such as ε-caprolactone monomer in the presence of an initiator and a catalyst having an active hydrogen group.

The catalyst used in this reaction is generally an organic tin compound, an organic titanium compound, an organic tin halide compound, etc., and the amount used is 0.1 to 5.
000 ppm, preferably 10-100 pf)m. The reaction temperature is suitably 100 to 280°C, and preferably carried out in an inert gas atmosphere.

It is not preferable for the reaction temperature to be higher than 280°C. This is because the depolymerization temperature of polycaprolactone is about 220 ~
This is because the temperature is 230°C, and if the reaction is carried out at a higher temperature, the polymer will decompose and the molecular weight will not increase. On the other hand, when the reaction temperature is below 100°C, the reaction rate is slow;
ineffective.

This thermoplastic polycaprolactone polymer has various molecular weights (i.e., relative viscosities) ranging from liquid to solid at room temperature, and is used for various purposes. The polycaprolactone polymers used have relative viscosities of 1.5-8.2 and 1.3-1.
Those less than 5 are coated on 2M4.

Polycaprolactone polymers having a relative viscosity of 1.3 to 8.2 are commercially available for various uses, such as boosting objects (Japanese Patent Laid-Open No. 60-240692), plastic clay (Japanese Patent Laid-open No. 60-240692), -42679), medical casts (Japanese Patent Laid-Open No. 58-81042), splint materials, face masks for radiation irradiation, wig molds (Japanese Patent Laid-Open No. 60-810-
215018), etc.

Specific examples of polycaprolactone polymers having a relative viscosity of 1.5 to 8.2 include PCL-H4 and H7, which are manufactured by Daicel Chemical Industries, Ltd. and are commercially available. Polycaprolactone polymers having a relative viscosity of 1.3 to less than 1.5 are also commercially available for various uses and are used as modifiers for general resins. A specific example thereof is PCL-Hl manufactured by Daicel Chemical Industries, Ltd. and commercially available. Therefore, these commercially available products may be purchased and used.

In addition, relative viscosity is according to JIS standard (K-6726),
Solvent: toluene, concentration = 1%, temperature: 25 ± 0.05°C
Measure with.

(Example) Example 1 A resin with a relative viscosity of 2.84 (polycaprolactone polymer with an average molecular weight of 70,000: PCL-H7 manufactured by Daicel Chemical Industries, Ltd.) is dissolved in toluene of LOOIIt, and a polyester braid yarn ( (equivalent to U8P8-θ) was continuously immersed in this solution and wound up while drying the solvent to coat the first layer. Next, this thread was coated with a resin having a relative viscosity of 1.40 (a polycaprolactone polymer having an average molecular weight of 20,000: PO manufactured by Daicel Chemical Industries, Ltd.).
L-H2) 4F was continuously immersed again in a solution of 100% toluene and dried, and the first layer (inner Hj) was a polycaprolactone polymer with a relative viscosity of 2.84, and the second layer A double-coated polyester braid yarn was prepared in which the surface layer (surface layer) was a polycaprolactone polymer with a relative viscosity of 1.40.

Example 2 1 g of polycaprolactone polymer having the same average molecular weight of 70.000 as in Example 1 was dissolved in 100 ml of toluene, and polyglycolic acid multifilament suture thread (U8P) was dissolved in 100 ml of toluene.
A thread (equivalent to 8-0, hereinafter referred to as PGA thread) was continuously dipped in this solution and wound up while drying the solvent to coat the first layer. This thread was then reduced to an average molecular weight of 20.000.
The polycaprolactone polymer 61 was continuously immersed again in a solution of 100 g of toluene and dried to obtain a PGA yarn double coated inside and outside as in Example 1 above.

Example 3 A resin having a relative viscosity of 1.58 (average molecular weight 40.000) was dissolved, and the same PGA thread as used in Example 2 was continuously immersed in this solution and wound up while drying the solvent. 1
Layer coating was performed. Next, this thread was continuously immersed again in a solution in which 5 g of polycaprolactone polymer having an average molecular weight of 20,000, which is the same as that used in Example 1, was dissolved in 100 txl of toluene, and dried. Relative viscosity 1.
58, a PGA yarn coated on the outside with a polycaprolactone polymer having a relative viscosity of 1.40.

Comparative Example 1 1 g of polycafloractone polymer having an average molecular weight of 70.000 as in Example 1 and 2 f of calcium stearate were dispersed in 100+wt of toluene, and while stirring this dispersion, a silk braid thread (equivalent to U8P8-0) was dispersed. ) was continuously dipped into the dispersion and dried to form a coated silk braid yarn.

Comparative Example 2 Polycaprolactone polymer 2f having the same average molecular weight as Example 8 of 40.000 and silicone 0.2f were mixed at 100%
txl of toluene, and continuously immersed silk braid yarn (equivalent to 08P8-0) in this solution and dried it.
It was wound into a coated silk braid yarn.

Comparative Example 3 2 g of polycaprolactone polymer having the same average molecular weight of 40.000 as in Example 8 was dissolved in 100 ml of toluene, and the same silk braid thread as in the above comparative example was dipped in this solution and dried to obtain a coated silk braid. Made with thread.

Comparative Example 4 A polycaprolactone polymer 2f having the same average molecular weight as Example 1 of 70,000 was dissolved in 100 at of toluene, and a silk braid yarn (equivalent to U8P8-0) was continuously immersed in this solution and dried. , a silk braid yarn coated with polycaprolact polymer.

Comparative Example 5 Same average molecular weight as Example 1, 70. 4 g of OOO polycaprolactone polymer was dissolved in 100 ml of toluene, and a silk braid yarn was dipped in this solution and dried to obtain a silk braid yarn coated with polycaprolactone polymer in the same manner as above.

The performance of each covered suture thread of Examples 1 to 3 and Comparative Examples 1 to 5 described above was as shown in the following table.

In addition, each performance value is an average value measured 5 to 10 times,
Comparative Example 6 in the table is a commercial product in which a silk braid is coated with a coating material consisting of beeswax and silicone.

Note) Explanation of the table above Adhesion #: Weight % of the coating agent coated on the suture Knot safety: Indicates the number of knots until the knot of the sample breaks without slipping. Indicated.

Knot-untying characteristics: The resistance value of the sample was measured when the knot was transferred.

Cantilever method: One end of the sample was held while the other end was left free in the 153 horizontal direction, and the hanging dimension of the free end was measured. The higher the number, the softer it is.

(Effects of the invention) As can be understood from the above table, Comparative Example 3 coated with a polycaprolactone polymer having a relative viscosity of 1.58 has excellent knot safety and knot-tying properties, but the cantilever method The measured value is 1401111, which is too soft and difficult to handle, and the relative viscosity is 2.34.
Comparative Example 5, in which the suture was coated with a polycaprolactone polymer, had the disadvantage that the suture thread did not slip well and was too hard, and was not satisfactory in terms of ease of sewing and tying during surgery. On the other hand, Comparative Example 6 has good overall operability such as ease of sewing and tying, but has some drawbacks in terms of bioabsorbability of the coating agent. However, in the multifilament suture of the present invention, the outer periphery of the multifilament thread is coated with a polycaprolactone polymer having a relative viscosity of 1.5 to 8.2, and the surface thereof is coated with a polycaprolactone polymer having a relative viscosity of 1.3.
Since the multifilament yarn is coated with a polycaprolactone polymer having a molecular weight of less than 1.5, the polycaprolactone polymer in the inner coating layer of the first layer imparts appropriate hardness to the multifilament yarn, making it easy to handle. The polycaprolactone polymer coating the surface of the second layer provides the suture with desirable knot safety and tying properties, making it an ideal surgical multifilament suture with good operability. .

Claims (1)

[Claims] The outer periphery of the multifilament suture has a relative viscosity of 1.
．． 5 to 8.2, the surface of which is further coated with a polycaprolactone polymer having a relative viscosity of 1.3 to less than 1.5. filament suture.