JPH0481456B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a method for packaging sutures made of biodegradable and absorbable materials. [Prior Art] Materials that are gradually decomposed and absorbed when left in the living body do not require re-surgery to be removed after use, so they have been used for sutures, etc., and have recently been used for various purposes. Expanding its use is being considered. Biodegradable and absorbable materials currently in use include collagen derived from natural products and polyglycolic acid-based polymers, which are synthetic polymers, but the latter is rapidly increasing in demand because it provides products of consistent quality. It is increasing. By the way, since polyglycolic acid is hydrolyzed by moisture in the body, hydrolysis proceeds gradually even if a small amount of moisture is present. Therefore, the product must be kept in a substantially moisture-free state until just before use. Therefore, Japanese Patent Publication No. 49-44754 proposes a package in which polyglycolic acid suture thread is completely dried and then vacuum-packed with a material that does not allow water vapor to pass through, or the package is replaced with water-free inert gas. It has been proposed and put into practical use. [Problems to be Solved by the Invention] Vacuum packaging or displacement packaging using inert gas is an ideal method in terms of preventing moisture from entering the package, but it is necessary to do all the sealing work of the package in a sealed container. There are problems that require special equipment as it has to be done indoors.
Moreover, the poor workability caused problems in terms of production efficiency. Therefore, the present inventors investigated a method of sealing a package in air. Normally, suture threads are wrapped in a mount panel and then placed in a mount cage so that they can be easily removed from the package cage, but if there is a lot of moisture in the mount paper, it is thought that moisture will migrate to the suture threads. The sutures were packaged using paper with as low a water content as possible, dried to bring the water content of the sutures below a certain value, and the package cage was sealed in air. After storing it for a certain period of time, we took it out and measured the water content of the suture.
The moisture content was significantly higher than before sealing. The reason for this is thought to be that moisture in the air sealed in the package gradually migrates to the suture thread, but it is also possible that moisture migrates from the mount panel to the suture thread. Therefore, sealing the package in air has been found to be problematic when long-term storage of sutures is desired. The present inventors continued various studies regarding the sealing of packages in the air, and as a result, they arrived at the present invention. That is, an object of the present invention is to provide a method for packaging suture threads that can be stored for a long period of time even if the package is sealed in air. [Means for Solving the Problems] It has surprisingly been found that the above object can be achieved by using paper with a high equilibrium moisture content after drying it to a predetermined moisture content or less. For long-term storage, sutures should be kept at a moisture content of 0.5% or less.
It is preferable to dry to 0.25% or less. That is, the present invention dries a suture made of a material that can be hydrolyzed by moisture in the body and absorbed into the body to reduce the water content to 0.5% or less,
A mount panel made of paper with an equilibrium moisture content of 3% or more at 25°C and 75% RH is dried to a moisture content of 2% or less, and the suture threads and the mount panel are placed in air using a water vapor impermeable material. This method of packaging biohydrolyzable suture thread is characterized by keeping the water content of the sealed suture thread at 0.5% or less by sealing it inside. [Function] When packaging is performed by the method of the present invention, the moisture content of the medical product does not change after sealing or becomes lower than before sealing, so it is possible to maintain a low moisture content (0.5% or less). Long-term storage is possible even when sealed in air. The reason why this phenomenon occurs is not clear, but it is thought to be because moisture in the enclosed air and in the product migrates to the paper during storage. However, it is surprising that this occurs even though the moisture content of the paper is higher than that of the product. [Example] Materials that can be hydrolyzed by moisture in the body and absorbed into the body include glycolic acid, lactic acid, and β.
-Hydroxybutylcarboxylic acid, β-propiolactone, γ-butyrolactone, δ-parerolactone, δ-caprolactone, ε-caprolactone,
Methyl-ε-caprolactone, p-dioxanone, methyl-p-dioxanone and dimethyl-p
- Homopolymers and copolymers obtained from dioxanone, etc., polyesters obtained by ring-opening polymerization of β-malolactone, and alkylene glycols such as ethylene glycol, propylene glycol, butylene glycol, and phenylene-bis-oxydiacetate. Examples include polyester obtained by polymerization. These may be used singly or in combination. In the present invention, the mount panel is heated at 25°C and 75°C.
It is necessary to use paper with an equilibrium moisture content of 3% or more at %RH. Any paper material can be used as long as the equilibrium moisture content is 3% or more. Further, the size, shape, thickness, etc. of the paper can be arbitrarily selected depending on the purpose. In the present invention, the above-mentioned mount panel is used after being dried to a moisture content of 2% or less. This keeps the moisture content of the suture constant or even reduces it after packaging. If the water content of the mount panel is greater than 2%, the water content of the suture thread will increase, which is undesirable. It is convenient if the mount panel dries together with the suture, as it can be immediately sealed, but in some cases, the mount panel can be dried separately from the suture. Drying may be carried out in a dry air stream at normal pressure, or may be carried out under reduced pressure. However, whichever drying method is used, the final sealing of the package is done in air. The most common water vapor impermeable material used in the present invention is a film made by laminating metal foils such as aluminum. The film is 2
Put the sheets together and heat seal the edges to make a bag. If the mount panel is dried by opening only one end of a bag made of such a film and inserting the mount panel and suture thread, the open end can be sealed immediately after drying. Incidentally, the suture to which the present invention is applied is usually sterilized, and gas sterilization using ethylene oxide or the like is preferred as the sterilization method. Furthermore, if the material is less likely to deteriorate due to radiation, it can also be sterilized by radiation. When gas sterilization is performed, drying should be performed after sterilization, and it must be ensured that the product remains sterile during the drying process. For this purpose, there is a method of performing the drying process in a sterile room, but the outside of the packaging made of water vapor impermeable material is further sealed with gas permeable and bacteria impermeable material, and sterilization and drying are carried out in this state. If the water vapor impermeable material is sealed by heating from the outside after drying is completed, it is convenient because the work can be carried out under a normal working environment. Practical Example 1 Cut high-quality paper (157 g/m ² ) with an equilibrium moisture content of 6.0% at 25°C and 75% RH into pieces of 9 cm x 6 cm.
Polyglycolic acid sutures were then wrapped, dried to various moisture contents, and sealed in air using aluminum laminate sheets. The suture was then stored at 60°C for 8 days, opened, and the water content of the suture was measured. The results are shown in Table 1.

[Table] As is clear from Table 1, the moisture content of paper is 2%.
If the water content is higher than 2%, the water content of the suture increases after sealing, whereas if it is 2% or less, it decreases, and can be stored for a long period of time. Comparative Example 1 Using synthetic paper with an equilibrium moisture content of 0.2% at 25°C and 75% RH (manufactured by Oji Yukasei Co., Ltd., trade name: Yupo) and polyglycolic acid suture thread, practical example 1
Drying and storage were performed in the same manner as above. Table 2 shows the measurement results of moisture content.

[Table] As is clear from Table 2, it is undesirable to use paper with an equilibrium moisture content of less than 3%, since the moisture content of the suture thread increases after sealed packaging. Practical Example 2 Paper with an equilibrium moisture content of 3.9% at 25°C and 75% RH (Jujo Paper Manufacturing, trade name Clean White) was dried to various moisture contents, and polyglycolic acid suture thread was separately dried to a moisture content of 0.052%. did. Then, in the same manner as in Example 1, both were sealed and stored together, and changes in the water content of the suture threads were measured. The results are shown in Table 3.

[Table] [Effects of the Invention] According to the present invention, a hydrolyzable suture thread can be sealed in the air, and the water content of the suture thread after sealing can be maintained at a low level. Therefore, there are advantages in that the sealing operation is easy and the product can be stored stably for a long period of time.

Claims (1)

[Claims] 1. A suture made of a material that can be hydrolyzed by moisture in the body and absorbed into the body is dried to a moisture content of 0.5% or less, and the equilibrium moisture content at 25°C and 75% RH is maintained. A mount panel made of paper with a moisture content of 3% or more was dried to a moisture content of 2% or less, and the suture was sealed together with the mount panel by sealing it in air using a water vapor impermeable material. A method for packaging biohydrolyzable suture thread, characterized by maintaining the water content of the suture thread at 0.5% or less. 2. The packaging method according to claim 1, wherein the material that is hydrolyzed by moisture in the body and absorbed by the body is a homopolymer of glycolic acid. 3. The packaging method according to claim 1, wherein the material that is hydrolyzed by moisture in the body and absorbed by the body is a lactic acid homopolymer or copolymer.