JP3770970B2 - Surface treatment method of medical article by argon gas cluster ion beam - Google Patents

Description

[0001]
The present invention relates to a surface treatment method for medical articles using an argon gas cluster ion beam. More specifically, the present invention suppresses the generation of insoluble foreign substances and the generation of volatile and soluble foreign substances by modifying or processing medical articles that require a high degree of safety and easy prescription. The present invention also relates to a surface treatment method for a new medical article that can suppress the secondary chemical reaction and reduce pain during prescription.
[0002]
[Prior art and its problems]
Conventionally, higher safety is required for syringes, containers, stoppers, tubes, packings, and the like used in medicine. In particular, in the case of an article as a polymer molded product, the filler or the like is detached from the surface in the wet state and becomes an insoluble foreign substance, or the blooming substance or volatile substance interacts with a pharmaceutical agent to become insoluble fine particles. It has become a very important issue to suppress this. Conventionally, such a problem has been dealt with by blending technology of a polymer composition as a raw material, but there are a method of coating other polymers by chemical treatment, a method of pressure laminating a Teflon film, etc. It has been developed.
[0003]
However, in the case of the coating method, the chemical properties are only slightly improved, the processing steps become complicated, the film thickness is not uniform, and the coating agent still peels off. In the case of the laminate method, the chemical properties are relatively improved, but the cost is increased by several tens of percent compared to the conventional product, and it is difficult to respond quickly to the new shape, generation of CFCs after incineration, etc. There is a new problem. In this way, efforts have been made to solve both problems, but the reality is that no fundamental solution has yet been found. There are also problems in sterilization of products using polymer materials including rubber stoppers. Traditionally, the most common sterilization process utilizes dry or wet heat, or a chemical sterilant such as ethylene oxide. However, polymer products that are sensitive to heat cannot withstand autoclave sterilization or dry heat sterilization. Discarding ethylene oxide and toxic degradation products derived from it is concerned about adverse environmental impacts, and in addition, it takes time-consuming operations to volatilize these chemical substances from sterilized products. Under these circumstances, radiation sterilization is now widely accepted as a means of sterilization of products using medical polymer materials, but it may cause harmful effects as a result of irradiation. However, the process is complicated.
[0004]
As described above, the method of solving each problem causes new problems, and the process is increasingly complicated. Looking at the current situation, in order to drastically solve the problem, the surface of the polymer material can be stabilized without damaging the bulk properties of the polymer material and without covering the surface with other substances. It turns out that it is important to modify the state.
[0005]
Under these conditions, surface modification by physical treatment can be considered. However, in general, many methods such as plasma processing have been proposed for this processing, but the effect is still unknown.
Further, the problem of surface modification of medical articles is not limited to those made of polymers. There are also problems that must be solved practically in devices for prescribing the body, such as injection needles, scalpels, and needles, as metal (including alloys) products.
[0006]
For example, conventionally, with regard to a medical injection needle, the tip and body of the needle have been polished by a dissolution method, or the surface of the needle has been coated with silicon to relieve pain during injection. However, dissolution polishing has a problem that a substance in the solution is recrystallized on the surface of the needle or a peeled foreign substance adheres again. In addition, in the US, silicone breast augmentation agents have been charged with product liability, and manufacturers have been demanding significant damages. For this reason, the supply of silicone coating agents for injection needles has been suspended. For this reason, manufacturers are considering their own measures, but at present, no method has been found to achieve the same effect without using a coating agent. Therefore, the needle not coated with the coating agent will return to the pain of 20 years ago, and the old problem of remarkably suffering will reoccur. In this respect, the surface of the injection needle is improved and processed. It has become a challenge.
[0007]
However, there are still no clues for such surface treatment.
The present invention has been made in view of the circumstances as described above, and an object thereof is to provide a new surface treatment method for a medical article that can solve the problems of the prior art.
[0008]
[Means for Solving the Problems]
The present invention, as to solve the above problems, the surface treatment method of a medical article according gaseous clusters noble gas cluster ion beam was generated by ionizing a massive collection of argon gas at normal temperature and pressure Argon gas cluster ions characterized in that the surface of a medical article molded from metal is irradiated with rare gas cluster ions under the following conditions (a) and (b) to modify or process the article surface: A surface treatment method for a medical article using a beam is provided.
a: number of irradiated ions 1 × 10 ^{14 to} 3 × 10 ¹⁵ ions / cm ²
b: Ion acceleration voltage 20 keV to 25 keV
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The invention is as an essential treatment with argon gas cluster ion beam as described above, the present invention is, as the embodiment of the above method, pharmaceuticals Ryoyo needle of the article as a metal formed article, female, Alternatively, the surface of these articles is modified or processed with argon gas cluster ions.
[0010]
The “modification or processing” described herein means that the surface of the article is physically or chemically changed. For example, the surface is cleaned, flattened, hydrophilized, It shows that it has effects such as hydrophobization, suppression of generation of eluate from articles and generation of insoluble particles.
The argon gas cluster ion beam employed in the present invention is an epoch-making technique in which ions of a cluster of gaseous elements or molecules at normal temperature and pressure are used as a new ion beam means.
[0011]
Compared to the monomer ion beam of a single element or single molecule, this gas cluster ion beam, in which hundreds to thousands of elements or molecules are aggregated and ionized, is emitted individually upon collision with a solid surface. The energy of the particles is from a few hundred to a few thousandths, and is characterized by low damage as a low energy beam and high density and large area processing.
[0012]
However, the application of such a gas cluster ion beam is an issue to be solved in the future, and there is a situation in which it is being investigated how to utilize the above features.
The present invention has been completed for the first time based on the completely unexpected knowledge that the gas cluster ion beam irradiation method as described above has an excellent effect as a means for solving the problems peculiar to medical articles. It is a thing.
[0013]
Hereinafter, the method of the present invention will be described in more detail with reference to examples. Of course, the present invention is not limited to the following examples.
[0014]
【Example】
Apparatus FIG. 1 illustrates the configuration of a processing apparatus (30 keV gas cluster ion beam apparatus) used in an embodiment of the present invention. Briefly, gaseous at normal temperature and normal pressure by introducing argon (Ar) gas to the nozzle (1), taken out through the skimmer (2) the jetted cluster, ionized by this ionizer (3) To cluster ions.
[0015]
The ions are accelerated by the accelerator (4) and irradiated onto the surface of the article to be processed supported by the holder (5).
The device includes a neutral gas cluster beam detector (6), a mass filter (7) as a mass separation unit, a Faraday cup (8), a gas cluster ion beam detector (9) and the like, together with vacuum evacuation means. It is also provided.
Example 1
A chlorinated butyl rubber plug of the size shown in FIG. 2 was used as a sample and irradiated with an argon gas cluster ion beam.
[0016]
Irradiation conditions were as follows.
<Number of irradiated ions> 1 × 10 ^{14 to} 5 × 10 ¹⁵ ions / cm ²
<Ion acceleration voltage> 20 keV to 25 keV
<Gas pressure> 4000 Torr
<Drawer voltage> 12V
The rubber plug after the irradiation was tested for the generation of insoluble foreign particles compared to the unirradiated one.
[0017]
In the test, 20 ml 0.45 μm filtered water was put into a GL bottle, a rubber stopper was plugged, boiled and left for 40 minutes, and evaluated by RION KR01 as an average value obtained by measuring 2 ml per specimen 3 times.
FIG. 3 shows the results, and it was confirmed that the generation of insoluble foreign matter was significantly suppressed in proportion to the irradiated ions by irradiation with an argon gas cluster ion beam. The effect more than the conventional laminated rubber stopper is acquired.
Example 2
As a sample, an intravenous needle having an outer diameter of 0.45 mm, made of SUS and subjected to electrolytic polishing treatment was used. FIG. 4 is a photograph showing the tip before processing, and it can be seen that foreign matter is adhered.
[0018]
This was irradiated with an argon cluster ion beam under the following conditions.
<Number of irradiated ions> 1 × 10 ^{14 to} 3 × 10 ¹⁵ ions / cm ²
<Ion acceleration voltage> 20 keV to 25 keV
<Gas pressure> 4000 Torr
<Drawer voltage> 12V
FIG. 5 is a photograph showing the surface state after the treatment at an irradiation dose of 3 × 10 ¹⁴ ions / cm ² , and it was confirmed that an excellent flattening effect by removing foreign matters was obtained.
[0019]
【The invention's effect】
As described in detail above, the present invention enables excellent modification and processing of the surface of a medical article.
Excellent effects such as remarkably enhancing the safety of medical articles and remarkably relieving pain during prescription can be obtained.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a configuration of an argon gas cluster ion beam irradiation apparatus used in an example.
FIG. 2 is a side view showing a rubber stopper as a sample.
FIG. 3 is a view showing a result of an insoluble foreign matter generation test from a rubber stopper.
FIG. 4 is a photomicrograph showing the surface state of the tip of an electropolished injection needle.
FIG. 5 is a photomicrograph showing the surface state after the treatment by the method of the present invention corresponding to FIG.

Claims (2)

A surface treatment method of a medical article using an argon gas cluster ion beam formed by ionizing clusters that are aggregates of gaseous argon gas at room temperature and normal pressure, the surface of the medical article formed from metal A surface treatment method for a medical article using an argon gas cluster ion beam, wherein the surface of the article is modified or processed by irradiating with argon gas cluster ions under the following conditions (a) and (b) :
a: number of irradiated ions 1 × 10 ^{14 to} 3 × 10 ¹⁵ ions / cm ²
b: Ion acceleration voltage 20 keV to 25 keV The method of claim 1, wherein the medical article is an injection needle, scalpel, or needle that is a metal molded article .

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