Medical Device & Diagnostic Industry
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An MD&DI December 1999 Column
A line of perfluoroelastomer O-rings is used for a variety of critical sealing applications. The O-rings provide overall chemical resistance and are capable of continuous service at 200° and 250°C peak temperatures. Typical sealing examples include mechanical seals, filters, flanges, valves, sensors, analytical instrumentation, semiconductor chambers, slit valves, vacuum components, wet stations, and furnace doors. MARCO RUBBER & PLASTIC PRODUCTS INC., North Andover, MA.
An injection molding machine is designed for small liquid silicone rubber (LSR) parts. The precise injection head is simple to use and clean. The machine can handle the extreme precision required for silicone intraocular lenses implanted permanently inside human eyes. KUNTZ MFG. CO., INC., Santa Ana, CA.
A tubing system consists of thin-walled tubing used for medical catheter systems, which have varying flexibility and performance characteristics from one end to the other. The ratio between stiff and flexible segments can be as high as 50:1. The company's proprietary manufacturing process allows the manufacture of this tubing with wall thicknesses as low as 0.0025 to 0.003 in. The PTFE inner liner capability allows for better tracking over a guidewire or other delivery device. HV TECHNOLOGIES, Trenton, GA.
A handheld infrared heat tool weighs 10 oz and can be used to shrink heat-shrinkable tubing and materials. The Glo-Ring's circular quartz elements open and close to encircle the workpiece, resulting in quick, even heating and shrinking. The elements attain their maximum operating temperature of 815°C in about four seconds and come in four OD sizes ranging from 0.5 to 3 in. The elements plug into the heat sinks for easy changing or replacing. Heat to the elements is controlled by a variable temperature control on the handpiece. The Glo-Ring can be used in the hand or in its stand. It is CE marked and meets all applicable EU safety standards. THE ERASER CO., Syracuse, NY.
A material is designed for one-step separation of plasma from red blood cells in a vertical format. The Hemasep V medium permits vertical separation of plasma components from small sample volumes of whole blood in under 10 seconds. Separated plasma will wick onto most lateral-flow materials, including the company's Predator membrane or Biodyne nylon 6,6 membranes. PALL CORP., Port Washington, NY.
A contract manufacturer has introduced an injection molding press for insert molding using a wide variety of materials. The tabletop Model 6010 offers the ability to switch from manual operation for process development and barrel purging to automatic for close control of process parameters. With a 5-tn clamp and 10,000-psi injection pressure, the press is well suited for production, short runs, and prototyping of materials that do not require screw-type
machines. Catheter and Disposables Technology, Plymouth, MN.
A digitally controlled fluid motion module designed for precision fluid dispensing and metering of chemicals and reagents can be used in kidney dialysis, chromatography, and syringe-filling applications. The pump, also available in a diposable model, features pulseless continuous flow, 100% volumetric efficiency, zero leakage, and near zero dead volume. It offers digital control and continuous delivery at 0.1% accuracy of flows from microliters to 1.2 L/min. ENCYNOVA INTERNATIONAL INC., Broomfield, CO.
A manufacturer of adhesives for microelectronic, semiconductor, and fiber-optic applications has produced a comprehensive guide to selecting adhesives for medical devices. The eight-page technical paper explains the potential uses of the company's USP Class VIcompatible adhesives. The 100%-solid, nontoxic adhesives have been used for bonding plastic tips to tubing, bonding fiber-optic bundles for light guides, and adhering diamond scalpel blades for surgical procedures. The company also formulates electrically conductive, thermally conductive, insulating, and potting compounds. EPOXY TECHNOLOGY INC., Billerica, MA.
Corona treatment increases the wettability of polymer surfaces, providing improved adhesion for printing, coating, and bonding. Suitable for use with injection-molded, blow-molded, or extruded parts, MultiDyne systems can be operated manually or incorporated into existing or new production lines. The units feature a durable, one-piece ceramic treating head appropriate for a variety of uses, including treating areas near metal inserts. Among the common medical product applications are petri dishes, test panels, tubing, and other disposable labware products. SOFTAL 3DT INC., Germantown, WI.
A manufacturer of specialty wire products designs, develops, and manufactures custom braid-reinforced tubing. The company's capabilities include producing thin-wall reinforced tubing, bonding layers of thermoplastic to fluoropolymers, and braiding all types of round or flat wire. NEW ENGLAND ELECTRIC WIRE, Lisbon, NH.
Hydrophobic air vent caps are available for sterile air transfer in patient care and particle/bacteria removal in biomedical applications. Filter materials used have a pore size rating of 0.2 µm in air. Hydrophobic filter media allow free air passage while blocking flow of aqueous solutions. Filters range in size from 1/4-in. ID to 110-mm ID and are also available in standard threaded bottle cap format. PERFORMANCE SYSTEMATIX INC., Caledonia, MI.
A line of precision-skived, ultrahigh-molecular-weight polyethylene (UHMW-PE) porous films is well suited for applications requiring high strength and chemical resistance. The D/W 402P UHMW porous films have a tensile strength in excess of 1000 psi. Pores, averaging 16 to 18 µm in diameter, are uniformly distributed in the x, y, and z directions. The films are available in thicknesses from 4 to 100 mil and widths in half-inch increments from 1/2 to 28 in. DEWAL INDUSTRIES INC., Saunderstown, RI.
A manufacturer of precision medical instruments and components produces Class III electrosurgical instruments that are biocompatible and engineered for reuse after autoclaving. A featured product is the LLETZ Loop molded electrode, available in seven loop sizes. Its molded construction encapsulates a 0.008-in. tungsten wire-loop cutting element. Stainless-steel blades as well as ball, needle, and other configurations are available. The manufacturer provides turnkey design, development, and production of all types of medical device components, including those requiring exotic metals or complex manufacturing techniques. INSTRUMED, DIV. OF NATIONAL WIRE & STAMPING, Englewood, CO.
A line of fluorescing adhesives cure upon exposure to visible and UV light. The MD 1000 series reduces cure time up to 50% when matched with UV curing lamps with the appropriate spectral output of UV and visible light. The adhesives fluoresce brightly when exposed to low-intensity black light, permitting manual or automated inspection of the adhesive bond line before and after the curing process. The company also offers UV curing equipment for these adhesives. DYMAX CORP., Torrington, CT.
A company offers thin, flexible, biocompatible coatings that can be permanently adhered to metal or plastic substrates. Slip-Coat hydrogel coating becomes slippery when in contact with body fluid, allowing for easy and safe manipulation of invasive devices. Medi-Coat coating contains active agents entrapped in a nonreactive polymer matrix. This controlled elution allows high concentrations at the device surface with low systemic concentrations. Echo-Coat echogenic coating improves the visibility of invasive devices during ultrasound procedures. STS BIOPOLYMERS INC., Henrietta, NY.
Suitable for either air- or liquid-filtering applications, a plastic net can be engineered to meet the user's thickness, strand density, width, diameter, and elasticity requirements. Naltex is available in thicknesses from 0.006 to 0.200 in. and with strand counts of up to 56 per inch. Netting can be made from polypropylene, polyethylene, polyimide, polyester elastomer, and other specialty resins. The company also extrudes netting in radiation-resistant polypropylene and in resins that meet USP Class VI requirements.Pyrogen testing and in-house precision slitting are also available. NALTEX/NALLE PLASTICS INC., Austin, TX.
A brochure describes a company's capabilities for multilayer, fine-line, and adhesiveless flex circuits, in addition to microvias, beryllium copper conductors, and cantilevered leads. A section on flexible circuit materials outlines conductors, insulators, adhesives, and finish. Tolerances, optimum sizes, flexibility, and temperature ratings are explained and ordering information is provided. The ISO 9002certified company also manufactures precision parts and a full line of standard and custom RFI/EMI shielding products. TECH-ETCH INC., Plymouth, MA.
A custom manufacturer of close tolerance, single- and multilumen small-diameter tubes produces braid-reinforced tubing to customer specifications. The controlled braiding operation produces close tolerance, wire-reinforced tubes in various configurations. The process utilizes single- or double-ended wires of various materials, including stainless steel, beryllium copper, silver, and polymer monofilaments. Wire diameters start as small as 0.002 in. PRECISION EXTRUSION INC., South Glens Falls, NY.
A company offers a line of standard equipment for dispensing two-part liquid silicone rubber. Multiple-component systems are available with fixed or variable ratios. Standard models include the tabletop laboratory unit, which is suited for rapid prototype and short production runs. Five- and 55-gal versions are also available. The standard models are virtually maintenance free and include extended warranties for pneumatic and hydraulic drive components to suit rigorous production demands at an economical cost. Complete turnkey molding systems are also available. ST SERVICES INC., Albany, NY.
A fast-setting, clear silicone rubber is available for prototype mold making. Parts-In-Minutes RP 6473 Si silicone is a low-viscosity casting compound that produces tough, flexible molds without cloudiness, according to the company. The clarity of the uncured material allows easy removal of air bubbles from the model surface before the silicone gels. After curing for 24 hours at room temperature, the new product exhibits properties including a 30 Shore A hardness, elongation of 300%, and tear strength of 55 to 60 ppi. CIBA SPECIALTY CHEMICALS CORP., East Lansing, MI.