Design engineers, custom molders can use it to mold better heat-moisture exchangers, formulator says
NEW YORK, N.Y.—Toray Industries Inc., recently introduced its TOYOLAC® Transparent ABS Resin to North American OEMs for medical applications in liquid-contact devices other than implants. The transparent ABS resin offers substantial opportunities for medical design engineers and custom molders to develop better components and final-use products, Toray said in a press release.
Benefits of using the resin are reported to include superior processability for injection molding, as well as excellent hardness, toughness, and resistance properties compared to traditional thermoplastics. Described as a cost effective replacement for many medical applications that require clear plastic, Toyolac can be used in housings, infusion sets, and other drug and blood contact devices, the company said.
Toyolac is also said to be well-suited for molding of heat-moisture exchangers (HMEs), which are medical devices that reduce mucus production and coughing by humidifying and filtering the air breathed through a stoma. Humidification of the tracheostomy is vital to maintaining thin secretions and preventing mucus plugs in mechanically ventilated patients.
Many models of HME designs are available for differing respiratory requirements. To ensure that HMEs operate reliably and enhance respiratory therapy, the material used in molding them is critical.
According to a release from Toray (www.toray.us), Toyolac has well-balanced chemical properties and is an FDA Drug Master File registered material. The transparent ABS resin is USP Class 6 tested and meets ISO 10993 for biocompatibility. Specific test results are reported to include -4 for blood interactions, -5 for in vitro cytotoxicity, -10 for irritation and skin sensitization, and -11 for systemic cytotoxicity. Toyolac also does not contain bisphenol-A, an industrial chemical that can cause health problems.
The material has structural strength and stiffness and is resistant to scratching, the company said. Heat moisture exchangers that incorporate Toyolac are reported to exhibit robust resistance to lipids, alcohol, and cleaning agents, providing patients with a long-lasting clear plastic design.
The HMEs are said to have advantages from an injection molding standpoint because the material requires lower molding temperatures and lower pressure requirements compared to polycarbonate materials. When using Toyolac resin, injection molders reportedly can achieve more mold cavitation with easier flowability of the resin at lower temperatures. Lower operating cylinder temperatures, ranging from 210°C to 260°C, are reported to provide smoother resin flow and increased cycle times with decreased part flash. While the excellent flow capabilities enable molding of thin-walled part features, the lower operating temperatures result in less tooling wear, decreased downtime, and overall longer mold life.
In addition, Toyolac is easy to machine, glue, and print. It is also said to have excellent solvent adhesive properties to meet multiple component assembly requirements.