Three Companies Partner for Glass-less Syringe Production

Sodick Plustech, a manufacturer of high-precision injection molding machinery, will showcase its V-Line two-stage plunger system at NPE 2012: The International Plastics Showcase, April 1-5, 2012, at the Orlando County Convention Center in Orlando, Fla. 

The company (Booth #363), will use the unique system to mold a medical syringe made of TOPAS cyclic olefin copolymer (COC) from TOPAS Advanced Polymers, based in Florence, Ky., in a mold developed by Nypro Inc. (Booth #4263), located in Clinton, Mass.

The prototype application demonstrates the use of COCs as a viable replacement for glass in syringe applications. TOPAS cyclic olefin copolymer is crystal clear with outstanding moisture barrier and dimensional consistency. For pharmaceuticals, TOPAS COC permits long-term drug storage and design flexibility, plus avoids the delamination problems associated with glass.
Unlike other engineering thermoplastics or glass, TOPAS polymer offers a non-ionic, minimally reactive surface. This non-polar substrate does not promote adsorption, denaturation, aggregation, or precipitation. With lower leachables and extractables, TOPAS resin preserves long-term drug purity ensuring better quality at high yields and potentially lower part cost.

A TOPAS COC staked needle syringe, produced in a Nypro mold, offers excellent barrier properties, without the release of ions or heavy metals and with lower particle levels especially in protein-based drugs compared to glass. TOPAS resin has very low fluorescence and can be aseptically filled or terminally sterilized in break-resistant, lightweight configurations. The material complies with international quality standards including USP, EP, and JP.

Sodick Plustech’s injection system uses a two-stage “V-LINE” method for plasticizing and injection. This proven technology delivers consistent shot volumes and melt densities matched with standard designs. Unlike a conventional in-line reciprocating screw system, the V-LINE plasticizing screw remains stationary during material transfer, minimizing axial wear and ensuring each pellet sees the same heat profile. The two-stage plunger injection unit provides an optimum screw size and plunger size combination (e.g., 40-mm screw with 32-mm plunger injection) for an ideal recovery time and shot size.

The “V-LINE” injection unit is controlled by a closed-loop system comparing actual speed to set speed and maximum melt pressure. User selectable limits can be easily input on the process monitor screen. Once the exact amount of material is transferred into the injection chamber, the injection plunger that is retracted via the melt is maintained to a set position. This design eliminates the need for a check valve, a primary source of material degradation and shot volume inconsistency. Prior to injection, the plasticizing screw is indexed forward creating a positive shut-off (exact dosing). This action prevents any opportunity for back flow of molten material back into the melt stream.

Nypro offers a configurable portfolio of barrier solutions across its three market segments. The Nypro/TOPAS/Sodick collaboration combines precision tool making, advanced material science, and advanced manufacturing systems to deliver plastic-based alternatives for glass applications. requiring tight dimensional tolerance, resistance to breakage, scale, and manufacturing efficiency

Sodick Plustech, with headquarters in Japan, is a global supplier of high-precision injection molding machines. U.S. facilities are in Schaumburg, Ill.