親和工業 List of Products and Services

Since its establishment, Shinwa Industry has prioritized quality and has been manufacturing various plastic molded products. In 2005, as part of this effort, we equipped ourselves with specialized custom machinery for the production of medical plastic products. By this time, our main customers had shifted to those in the pharmaceutical and medical industries. To accept commissions for plastic molding from customers with medical device manufacturing and sales licenses, we obtained a medical device manufacturing and sales license in 2007 (and a medical device manufacturing registration certificate in 2017). Furthermore, as proof of our management system required for medical devices, we obtained ISO 13485 certification in September 2019. Among plastic molding manufacturers in Japan, few have acquired ISO 13485, and at Shinwa Industry, we achieved this certification as a testament to the trust and reliability we offer to our business partners. In 2020, we obtained a second-class medical device manufacturing and sales license. As a result, plastic molding for the medical industry has become even more central to our operations, and we are now able to accommodate hygiene and sterilization processes.

• Plastic utensils and containers

This is a part of a microfluidic chip made of acrylic resin (PMMA) produced by Medical Plastic Molding.com. Such microfluidic chips have fine grooves ranging from 50 microns to 100 microns, and require a high level of flatness and polishing to ensure that reagents flow smoothly. To achieve a high level of flatness, discussions must go beyond just mold design to include mold processing methods. This microfluidic chip is not only designed for the product but also the resin mold is designed in-house by Medical Plastic Molding.com, and we proceed with discussions with customers from the mold design stage. We provide various cost-reduction design proposals in product design and mold design.

• Plastic utensils and containers

This ABS syringe is an injection-molded product designed to fill medications into the body. Since the outer surface of the product may come into contact with the body's mucous membranes, a level of finish is required where the parting line cannot be felt by hand. This surface precision is achieved solely through molding without any deburring. Of course, the inner wall of the syringe has a draft angle of 0 degrees and is free from sink marks and other defects. At medicalplasticmolding.com, we use a tapered structure for aligning the positions of the product components during mold design to eliminate any misalignment of the parting line surfaces, achieving a high-precision molding with a parting line misalignment of less than 5/1000. We can produce high-quality molded products like this one, where the parting line is virtually indistinguishable.

• Plastic utensils and containers

The piston of a syringe used for medical purposes or similar applications is critical, as any liquid leakage can be a fatal flaw when injecting medication or reagents. The syringe pistons manufactured by Medical Plastic Molding.com use a silicone O-ring at the tip, eliminating concerns about leakage. This time, we listened to the customer's sketches and product requirements and conducted product design in-house. Additionally, before moving to mass production, we created samples using a 3D printer to consider the packaging form of the product. However, the actual-sized sample revealed that improvements were needed in the product design (adding a larger radius to the part that touches the fingers for a softer image and feel). Therefore, by creating samples at actual size before starting mold production, we were able to develop the new product without incurring unnecessary costs (design changes) or time (revisions). We recommend that, alongside product design, you create samples using a 3D printer in advance for your review.

• Plastic utensils and containers

This plastic injection molded product is a medical syringe made of PP (polypropylene). Due to the relationship with the piston inside, the inner draft angle is 0 degrees. Unlike medical instruments such as syringes, this thin-walled medical syringe is designed to have a thinner wall on the sides because the contents are heated during use. Generally, having a thinner wall can lead to uneven thickness, causing the product to bend like a banana, and a 0-degree draft angle can often result in scratches on the plastic injection molded product during demolding. However, by incorporating fine adjustments in the mold design, our company can suppress product bending, eliminate scratching during demolding, and mold the product to fully meet the specifications desired by our customers. By considering material properties from the mold design stage, we can achieve high-precision and high-quality plastic molding.

• Plastic utensils and containers

Generally, the mainstream in the industry is to attach a cap to a thin metal pin for the anesthetic needle core, but this anesthetic needle core is a one-piece molded product. We have achieved the production of a product that meets the specifications requiring a withdrawal taper of 0 degrees for the thin part with a diameter of 0.6 mm and a length of 125 mm, and prohibits particle lines (PL), split lines, and voids. There are many types of needle core lengths, and since the tip part is cut to match the needle length, it cannot be used if there are voids on the cut surface. Additionally, the advantages of a one-piece molded product include: 1. Safety (with metal anesthetic needle cores, there was a risk of accidentally stabbing the nurse's hand during handling, leading to infection, but plastic is soft and does not stab, making it safe) 2. Usable for patients with metal allergies (with a metal core, there was a slight generation of metal powder due to friction inside the needle, but using plastic eliminates this issue) 3. Easy disposal (since it is all plastic, it can be processed collectively) 4. Cost reduction (the raw material cost is lower than metal, and there is no adhesive process)

• Plastic utensils and containers

This medical plastic injection molded product is a thin-walled tube used for real-time PCR. Real-time PCR refers to the monitoring and analysis of amplification through PCR (polymerase chain reaction) in real-time. This thin-walled tube for real-time PCR is made from polypropylene, characterized by its thickness of 0.3 mm. Polypropylene is known for its excellent chemical resistance and is one of the commonly used materials in medical plastic molding. By having a wall thickness of 0.3 mm, this thin-walled tube improves thermal conductivity, allowing for reduced heating and cooling times. Initially, this medical real-time PCR thin-walled tube was produced as a prototype through contract processing, but later, mass production injection molding was also contracted. Our company can handle everything from product design to mold design, allowing us to consistently manage the process from prototype contract processing to subsequent mass production.

• Plastic utensils and containers

This plastic injection molded product is a thin-walled dispensing tip used for medical purposes. Even when referring to medical thin-walled tips, there is a wide variety used in the medical industry, ranging from short tips to long tips, and from thin tips to thick tips. This dispensing thin-walled tip was developed in collaboration with our customers, featuring a wall thickness of 0.3 mm at the mouth section and a thicker section at the tip measuring 0.7 mm, resulting in more than double the thickness difference, which is its most significant characteristic. Due to the substantial thickness difference of 0.4 mm between the thick and thin sections, we provide design advice during the product design phase to include quality improvement measures to prevent weld lines from occurring when filling plastic resin from the gate. Additionally, we have production experience with such medical thin-walled tips, including those with a tip inner diameter of φ0.4 mm.

• Plastic utensils and containers

Among medical plastic products, there is a demand for real-time PCR tubes to have a body thickness that is as thin as possible. Since real-time PCR tubes undergo repeated heating and cooling, they must have good thermal conductivity. However, when the thickness is reduced, even a slight misalignment between the core and cavity of the mold can result in significant uneven wall thickness in the product. For example, if the product wall thickness of the tube is 0.4 mm (thin wall), a core misalignment of 0.05 mm will result in one side being 0.45 mm thick and the other side being 0.35 mm, leading to a 0.1 mm discrepancy. A 0.05 mm misalignment becomes a 25% discrepancy in a 0.4 mm thickness. Therefore, at the design stage of the mold, it is necessary to devise a mechanism for aligning the cavity and core. Additionally, when optimizing plastic molding conditions, it is important to ensure that uneven wall thickness does not occur.

• plastic

This is a book for designers that compiles the technical know-how of medical plastic injection molding from a company equipped with permits for medical device manufacturing, ISO 9001 certification, and injection molding facilities with clean rooms of Class 10,000 or lower.

• Processing Contract