JP7402526B2 - resin products - Google Patents

Description

The present invention relates to resin products, and in particular, resin products that have a built-in RFID that can withstand repeated exposure to environments such as high-temperature, high-pressure, and high-humidity autoclave steam sterilization, and environments where they are subjected to impacts such as drops. Regarding products, it also applies to the pharmaceutical manufacturing field where aseptic operations are essential, the physical and chemical fields, instruments and machines used in medical procedures such as treatment and surgery, and manufacturing sites for industrial products and retort food that are exposed to high-temperature environments of around 150°C. This article relates to resin products with built-in RFIDs, which are machines and/or parts used in applications such as machines and/or parts.

RFID (radio frequency identifier) technology has developed rapidly since the 2000s, and many concrete examples can be found especially in medical settings. For example, in actual medical settings, traceability is required not only for medical instruments such as tweezers and forceps, but also for the handling of various medical instruments. Stamping with two-dimensional barcodes using markers or the like, or attaching RFID tags to the sides of medical instruments, are beginning to be used to manage individual medical instruments.

Two-dimensional barcodes require reading the engraved part, so it takes time to detect the printed position, and they can become unreadable due to blood adhesion, wear, rust, etc., making them difficult to use in operating rooms, etc. There are cases where it becomes difficult.

On the other hand, RFID is easier to read and can read multiple barcodes at the same time, making it more efficient than two-dimensional barcodes. There was a problem in that it could not be subjected to high-pressure steam sterilization, which is the most common method.

Therefore, in Patent Document 1, the case is sealed in two parts made of ceramic and bonded, and in Patent Document 2, the case is sealed and bonded in an exterior material having a lid made of synthetic resin. Efforts have been made to protect RFIDs from high temperatures, high pressures, and high humidity. Further, in Patent Document 3, the RFID encapsulated as described above is later press-fitted into a metal medical device, pasted on it, or tied together.

The general conditions for high-pressure steam sterilization are high temperatures of 121 degrees Celsius or higher, high pressures of 110 kPa or higher, and 100% humidity, and since it has the property of penetrating even the slightest gaps in adhesives, infiltration can cause electronic circuits to malfunction. It was possible. We actually produced a test case made of resin, sealed the RFID with adhesive only, and subjected it to a high-pressure steam sterilization test at 135°C, 30 minutes, 230kPa, which was more severe, with reference to 3.2 of Non-Patent Document 5. As a result, similar to Non-Patent Document 5 Description 3.6, it was confirmed that adhesion alone was not a sufficient response.

Not only that, but in terms of temperature, during injection molding, it is exposed to a high temperature environment of 300℃ for a short period of about 5 seconds, so it is actually impossible to integrate RFID into a resin product and mold it as is. Ta.
Although there is a lineup of commercially available RFIDs that are compatible with 121°C and are supposedly sealed in ceramic fired cases, if you try to injection mold them as is, they will shift, so some kind of additional means of positioning is required. However, the temperature setting of 135° C. required for high-pressure steam sterilization for Creutzfeldt-Jakob disease and BSE was not guaranteed, and even more so, the high temperature environment during injection molding was not sufficiently addressed.

Furthermore, when repeatedly reusing medical instruments, etc., cleaning and sterilization operations are standardly performed as a series of cycles, and when attached by fitting or bundling as in Patent Document 3, cleaning and sterilizing to remove dirt, It is not easy to be exposed to detergents, steam, and gases that are used as sterilization media, and if the cleaning process is not carried out using ultrasonic cleaning, there is a concern that dirt may remain in the vicinity of binding parts and fitting parts. .

Patent Document 4 is an earlier patent application filed by the inventors of the present application, which is unpublished at the time of this application. This application was filed with the intention of supplementing the application of Patent Document 4, and in particular, the impact on RFID under high temperature, high pressure, and high humidity environments was insufficiently studied. We found this in description 3.6 of Non-Patent Document 1, and based on the experimental results, we obtained new knowledge that could not be covered at all in Patent Document 4, and completed the present invention.

Japanese Patent Application Publication No. 2007-183840 Japanese Patent Application Publication No. 2013-140465 JP2019-109942A Patent application 2019-195364

Telecommunications Promotion Foundation Research Report 2008 (National Diet Library Digital Collection) p245. pdf, "Research on information management of surgical instruments in hospitals using RFID", Research representative Kazuhiko Yamashita, Associate Professor, Faculty of Health Sciences, Tokyo Medical and Health University

The present invention has been made in view of the problems of the above-mentioned background art, and its purpose is to enable RFID to maintain its performance even when repeatedly exposed to environments such as high-temperature, high-pressure, and high-humidity autoclave sterilization. We aim to provide an integrally molded resin product that has mechanical strength comparable to that of metal, which can be continuously demonstrated and not easily broken even when subjected to impact from a fall, and is approximately 1/3 to 1/4 as light as metal. This can contribute to the spread of management using RFID, not only for medical devices but also for machines and/or parts used at manufacturing sites of industrial products and retort food, regardless of the embodiment. Our goal is to provide resin products.

In order to achieve the above object, the present invention provides resin products as described in the following [1] to [6].
[1] The RFID is fixed in a case without a lid for positioning, with its surroundings covered with a heat insulating protective layer, and the RFID is built in and integrally molded into the product shape using resin. A built-in resin product, characterized in that the material forming the lidless case is a thermoplastic resin having a heat deformation temperature of 240° C. or higher, the same as the resin forming the resin product. product.
[2] The resin product according to [1] above, wherein the resin product is an RFID tag that is used by being attached to another product.
[3] The above-mentioned RFID tag is characterized in that the attachment part to another product is a convex part, and the part other than the attachment part is designed so that a gap is formed between the part and the product. 2] The resin product described in [2].
[4] The thermoplastic resin is one of polyphenylene sulfide resin (PPS), polyetheretherketone resin (PEEK), polyethersulfone resin (PESU), and polyetherimide resin (PEI). , the resin product according to any one of [1] to [3] above.
[5] The resin product according to any one of [1] to [4] above, wherein the thermoplastic resin contains carbon fiber as a filler.
[6] The resin product according to any one of [1] to [5] above, wherein the heat-insulating protective layer is made of silicone rubber .

According to the present invention described above, the work is performed using the same procedure as insert molding, but by forming the lidless case for positioning the RFID from the same resin as the target resin product instead of metal etc. By integrally molding it so that it melts into the resin product, it can be fixed without creating any gaps around the RFID, so even if high temperature, high pressure, and high humidity steam sterilization is repeated, there will be no infiltration of high temperature, high pressure, and high humidity. It is a resin product that can protect RFID from etc.
In addition, according to the present invention, since the heat-resistant resin is formed by containing carbon fiber as a filler, it can have mechanical strength equivalent to that of metal products, and protects the RFID even if it is repeatedly subjected to shocks such as dropping. It becomes a resin product that can be used.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing forceps, which is a surgical medical instrument, as an embodiment of a resin product according to the present invention. FIG. 2 is a plan view schematically showing a case without a lid for positioning when integrally molding an RFID incorporated in the resin product shown in FIG. 1. FIG. FIG. 3 is a longitudinal cross-sectional view of the case without a lid for positioning shown in FIG. 2; FIG. 2 is a perspective view illustrating an attached state in which the resin product is an RFID tag. FIG. 2 is a plan view schematically showing the shape of a resin product that is an RFID tag. 6 is a vertical cross-sectional view of the RFID tag shown in FIG. 5. FIG. It is a load-crosshead movement diagram obtained in a three-point bending test for a prototype forceps.

Hereinafter, an embodiment of a resin product according to the present invention will be described in detail with reference to drawings, but the resin product of this embodiment is merely illustrated to facilitate understanding of the present invention, and is limited to this. It is not something that will be done.

As shown in FIG. 1, the forceps 1, which is a resin product of the present embodiment, is integrally molded with the resin of the main body surrounding the RFID 2, which transmits and receives by wireless communication, so as to be melted therein.

As shown in FIGS. 2 and 3, the lidless case 5 for positioning when integrally molding the RFID 2 on a resin product has a plate-shaped rectangular portion that serves as a positioning guide when attaching this part to a mold. 3, and a cylindrical part 4 that serves as a storage part for the RFID, and the RFID 2 is fixed in the cylindrical part 4 with its periphery covered by a heat insulating protective layer 6, and the resin product (forceps) 1 is It is formed as a part for injection molding.

FIG. 4 shows that when the resin product according to the present invention is an RFID tag 8, the object managed by RFID 2 is, for example, a medical instrument, a notch 10 is provided in the body 9, and the RFID tag 8 is attached to the notch 10. Shown is installed.
Here, the cylindrical convex portion 7 that minimizes the contact area with the body 9 of the medical device plays an important role, and a gap 11 is formed between the RFID tag 8 and the body 9 of the medical device. . Further, the RFID tag 8 is fixed to the body 9 of the medical instrument via the cylindrical convex portion 7 using rust-free metal fasteners, ultrasonic welding, or the like. The presence of the gap 11 formed between the RFID tag 8 and the body 9 of the medical device facilitates exposure to detergents, steam, and gases that serve as media during cleaning and sterilization, reducing the effort required for these operations. Not only is it possible to save labor, but cleaning and sterilization can be performed reliably, and management using RFID2 is also facilitated. In the example, the RFID tag 8 is fixed to the body 9 of the medical device at two locations where the convex portion 7 is formed, but in recent years the RFID 2 has been miniaturized, and the planar area of the RFID tag 8 is about 2 square centimeters. In view of the current situation where only one cylindrical convex portion 7 is provided, sufficient mounting strength can be ensured even if the number of cylindrical convex portions 7 is one.

FIG. 5 is a plan view illustrating the shape of the RFID tag 8 in which the RFID 2 is integrally molded. As for the number of cylindrical protrusions 7 formed on the RFID tag 8, the reliability of cleaning and sterilization increases when the number is smaller, provided that the mounting strength can be ensured as described above, and the shape is adjusted to satisfy the requirements. The method is not limited to this as long as a mold can be manufactured. FIG. 6 shows that the RFID 2 is integrally molded with resin and has a built-in component fixed with the periphery covered by a heat insulating protective layer 6 in a case 5 without a lid for positioning. 6 is a vertical cross-sectional view of the RFID tag 8 shown in FIG. 5. FIG.

The resin that forms the resin products according to the present invention (for example, the forceps 1 and the RFID tag 8 described above) and the resin that forms the lidless case 5 for positioning during the integral molding are the same resin. It is preferable that resins with mechanical strength comparable to metals have appeared due to advances in material technology, can be used for injection molding, and have a heat distortion temperature of 240°C or higher, which is twice the general temperature for high-pressure steam sterilization. For example, but not limited to, thermoplastic resins such as polyphenylene sulfide resin (PPS), polyetheretherketone resin (PEEK), polyethersulfone resin (PESU), and polyetherimide resin (PEI) can be used. . Alternatively, mixtures of these can be used.
In this embodiment, the forceps 1 and the RFID tag 8 described above were formed using polyphenylene sulfide resin (PPS) as the material.

In order to further strengthen the mechanical strength of the resin as a surgical instrument, carbon fiber can be used as a filler, although it is not limited thereto. When carbon fiber is included, its content in order to increase strength is usually about 10 to 50% by weight, preferably about 25 to 45% by weight, based on 100 parts by weight of the base resin. Various test results have shown that glass fibers commonly used as fillers lack toughness (stickiness).

Among the requirements of the present invention, the lidless case 5 and the heat insulating protective layer 6 for positioning will be described in detail below.

In order to integrally mold the resin product according to the present invention with the RFID 2 so that it melts into the resin product by injection molding, the procedure is similar to insert molding, so the case 5 without a lid for fixing and positioning the RFID 2 is It is necessary to thoroughly dry and harden it and prepare it as a part in advance.

In the case of a small number of lots, manual processing may be considered, but in the case of a large number of lots, it is natural with current industrial production technology to plan for automation using robots or the like. At that time, in order to discover voids and prevent a decrease in yield, it is common sense to use optical methods such as inspection using an optical microscope or enlarged camera images, and whether it is a stationary type or a pass-through type, it is necessary to use a constant temperature apparatus. It is common sense to accelerate drying and curing from the viewpoint of productivity, and it is reasonable in the present invention to make the case for positioning a structure without a lid so that this can be easily carried out. is important.

In addition, when integrally molding with the RFID 2, the material that adheres to the lidless case 5 for positioning and forms the surrounding heat-insulating protective layer 6 is incorporated into the resin product (for example, the forceps 1, the RFID tag 8). When integrally formed by injection molding, it is exposed to high temperatures of 300° C. for about 5 seconds, so it is necessary to use a material that can withstand high temperatures so that the heat insulating protective layer 6 does not melt. An adhesive, resin, silicone rubber, or the like having a temperature of ℃ or higher is used.

In the case of adhesives, inorganic or organic adhesives can be used, and specific examples include Three Bond #3732 manufactured by Three Bond and LOCTITE ABLESTIK A316 manufactured by Henkel. Moreover, in the case of resin, thermoplastic resin, thermosetting resin, etc., or a mixture thereof can be used. Specific examples of the silicone rubber include silicone RTV rubber for moisture-proof coating manufactured by Shin-Etsu Chemical Co., Ltd.

As shown in FIG. 3 or FIG. 6, it is preferable that the formed heat insulating protective layer 6 uniformly surrounds the outer periphery to ensure that the RFID 2 is not exposed. Further, the heat insulating protective layer 6 to be formed may be formed of a single layer, or may be formed of a plurality of layers in order to withstand high temperature, high pressure, and high humidity.

Regarding the mechanical strength of the resin product according to the present invention, advances in material technology have led to the emergence of resins with mechanical strength comparable to metals, which can be used for injection molding, and as mentioned above, the heat distortion temperature is the general temperature for high-pressure steam sterilization. According to the results of a test commissioned to an external institution, we selected forceps with a temperature of 240°C or higher, which is twice the temperature of 240°C, which is twice the temperature of It was confirmed that after 70 cycles of 20 minutes, and after conducting an additional accelerated deterioration test equivalent to 9 years, there was almost no decrease in mechanical strength.

Regarding mechanical strength, specifically, in the room temperature three-point bending properties of a prototype forceps, fulcrums were made at 6 cm intervals with a 3.0 cm gap at the tip, and the center, that is, the 6 cm from the end, was When pushed in at a speed of 1 cm/min, the maximum load is preferably 200 N or more, more preferably 240 N or more. In addition, with short tweezers, etc., make fulcrums at 4cm intervals with a 1.5cm gap at the tip, and when pushing in the center, 3.5cm from the end, at a speed of 1cm/min, measure in the same way. did. In this case as well, the maximum load is preferably 200N or more, more preferably 240N or more. The upper limit of this maximum load is not particularly limited, but normally, if the upper limit for surgical instruments is about 300N, they will not break.

Here, the maximum load in three-point bending properties at room temperature is measured as follows.

Measuring device: Instron precision material testing machine Model 5848
Measurement method: Crosshead travel method Measurement environment: Room temperature in the atmosphere Test piece shape: The tip was cut out and tested Distance between fulcrums: 60 mm
Test speed: 10mm/min
Indenter/fulcrum radius: 2.5mm
Data processing: Instron data processing system "Bluehill 2"
Data acquisition interval...0.01s
Calculation method: Maximum load

The maximum load was read from the load-crosshead movement diagram obtained in the three-point bending test.
Typical measurement results are shown in FIG.

Furthermore, biological safety tests on the prototype forceps revealed no problems in terms of cytotoxicity, skin sensitization, and intradermal reactions, and optical microscopic examination revealed that the surface of the molded forceps was made of resin. It was also confirmed that the filler carbon fiber was completely trapped inside and there was no fuzz.

When applied to surgical instruments, it becomes possible to ensure traceability and prevent serious mistakes such as leaving surgical instruments in the body. In addition, when comparing the same shape, the weight is 1/4 to 1/3 of a metal surgical instrument, so even among surgical medical instruments, the weight of the chest opener and wound retractor is a burden on nurses and doctors. When it comes to medical equipment, it can help reduce physical fatigue even during long-term surgeries.

Furthermore, if the resin product is the above-mentioned RFID tag 8, the shape can be freely deformed using a mold and it can be integrally molded, so even if it is attached to the body of a medical device that will be reused after high-pressure steam sterilization. As long as there is at least one convex portion 7 for the purpose of ensuring a gap, a design that makes it easy to provide other gaps can be easily achieved.

In particular, the resin product of the present invention is a resin with a built-in RFID that is used in environments where it is repeatedly exposed to environments such as high-temperature, high-pressure, and high-humidity autoclave steam sterilization, or where it is subject to impact due to falling. In addition, it can be used as a product, and it can also be used in the pharmaceutical manufacturing field where sterile operation is essential, in the physical and chemical fields, and in medical procedures such as treatment and surgery, as well as industrial products and retort food that are exposed to high-temperature environments of around 150°C. It can be used as resin products that are machines and/or parts used at manufacturing sites.

1...forceps (resin product)
2...RFID
3... Plate-shaped rectangular part 4... Cylindrical part 5... Case without lid 6... Heat insulation protective layer 7... Convex part 8... RFID tag (resin product)
9...Body 10...Notch 11...Gap

Claims (6)

A resin with a built-in RFID, which is made by fixing the RFID in a case without a lid for positioning, with its surroundings covered with a heat-insulating protective layer, and integrally molding it into the product shape with resin. A resin product, characterized in that the material forming the lidless case is a thermoplastic resin having a heat distortion temperature of 240° C. or higher, the same as the resin forming the resin product. The resin product according to claim 1, wherein the resin product is an RFID tag that is used by being attached to another product. According to claim 2, the RFID tag is designed such that the attachment part to another product is a convex part, and a gap is formed between the part and the product other than the attachment part. resin products. Claim characterized in that the thermoplastic resin is any one of polyphenylene sulfide resin (PPS), polyether ether ketone resin (PEEK), polyether sulfone resin (PESU), and polyetherimide resin (PEI). The resin product according to any one of 1 to 3. 5. The resin product according to claim 1, wherein the thermoplastic resin contains carbon fiber as a filler. 6. The resin product according to claim 1, wherein the heat-insulating protective layer is made of silicone rubber .

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