Showstoppers
A selection of innovative new products exhibited at MEDTEC (Amsterdam) and Manufacturing Week (Birmingham)
Optical gas sensor
Manufacturer of anaesthesia systems develops OEM component
Users of anaesthesia workstations expect them to provide precise and reliable measurement of CO2 and oxygen, and low-flow capability. Moreover, they should be free of cross-sensitivity properties with organic vapours and be compatible with new anaesthetic agents, some of which may have unfamiliar minimum alveolar concentration values. 
The gas analyzer that is at the heart of anaesthesia equipment plays a critical role in all of these functions. Dräger Medizintechnik GmbH (Lübeck, Germany) has developed the Infrared Rapidly Identifying Analyzer (IRIA), which identifies the anaesthetic agent and responds when a change in agent occurs. The gas identification threshold is so low, according to OEM and special projects manager Melchior Leiss, that the IRIA can precisely record inspiratory and expiratory wash-in processes.
"Few manufacturers in the medical device industry are able to produce an anaesthetic gas sensor," says Leiss, who premiered the OEM component at MEDTEC. "The technology is highly sophisticated, requiring specialists in everything from optical physics to gas measurement." Dräger's experience as a manufacturer of end-use equipment that incorporates this technology puts the company in a prime position to develop such state-of-the-art components, he adds.
While OEMs have been impressed by the performance specifications of the device, according to Leiss, they often raise the question of reliability. "Gas-measurement instruments are the single most-expensive component in anaesthesia stations, and when they fail, the repair costs can be substantial," says Leiss. Consequently, potential customers want every assurance that the device is reliable, and that type of guarantee is one that Dräger is uniquely positioned to supply. "The sensor has been part
of Dräger's equipment for two years now, so OEMs have some real-life examples with which
to compare the claims."
The IRIA system measures gases and anaesthetic agents by means of infrared light absorption in the 4–5- and 8–10-µm spectral ranges. Data are channeled through a serial port based on RS-232 specifications located on the data-processing board.
The company is currently considering expanding its OEM services to provide full contract manufacturing, according to Leiss.
Dispense valves
Disposable pinch-tube valves suited for microbonding applications
An expanded range of valves is designed for accurate dispensing of adhesives, sealants, resins, lubricants, and pastes in extremely small volumes. LCL DispensTech (Wellingborough, Northants, UK) views the medical device and pharmaceutical industries as key potential purchasers of its Dispensit valves.
"Conventional mechanical valves include potentially dead areas in their design," says company director John Thomas. "A curing product is liable to harden inside, resulting in clogging or imprecise outflow. Our system includes a highly efficient, disposable, straight-through pinch-tube valve with no dead internal areas," he says. 
In addition, the valves operate according to positive volume displacement, which ensures dispensing of a constant amount of fluid, regardless of viscosity, within a defined range. "Other types of valves rely on time, pressure, and fluid viscosity always remaining constant," adds Thomas.
A UK-based manufacturer of hearing aids uses the company's line of valves to apply tiny dots of adhesive on miniature components. Knowles Electronics uses three dispensing valves operating in tandem to deposit adhesive on components that measure 0.156 x 0.127 mm with a cycle time of a few thousandths of a second. The valves provide the "fine control, repeatability, and low maintenance required for this application," says the company's automation supervisor Richard Eatwell. They replaced manually operated dispensers.
Filters
Corrugated cellulose filter media save process steps
Manufacturers of heat-moisture exchangers have the potential to save process steps by using cellulose media corrugated in an F-flute configuration. Whatman International Ltd. (Maidstone, Kent, UK) presented the product at its MEDTEC stand. 
The fine and consistent corrugations, according to healthcare marketing manager Deirdre Thom, offer a large surface area for moisture transferal.
The material is available in a variety of roll widths to suit individual needs and is shipped ready for impregnation.
Whatman supplies an array of interchangeable filter housings, adapters, connectors, and media to device OEMs. Its media are suited for use in all components of diagnostic kit manufacture, from specimen collection and sample preparation to lateral-flow or flow-through devices.
Rapid prototyping materials
New range of materials permits vacuum casting of functional prototypes
A range of vacuum-grade materials that replicate rubber, PMMA, polyethylene, polypropylene, and ABS are designed to permit the production of fully functional prototypes by means of vacuum casting. The materials, which were introduced by Ciba Specialty Chemicals plc (Duxford, Cambs, UK) at Manufacturing Week, complement the company's existing polyurethane rapid prototyping materials range.
The seven new systems were designed specifically for manufacturers that have invested in vacuum casting technology. Characteristics of the individual formulations include a black glass-filled system with high temperature resistance, one with high flexural modulus for a longer working life, black and pigmentable versions with good impact strength, and a black tear-resistant Shore 65 system that simulates rubber.
Other products introduced by Ciba at Manufacturing Week include the low-shrinkage Ureol Fastcast system suited for casting sections in dimensions up to 100 mm, and a high-speed machinable composite board developed for the moulding of multiple dimensionally accurate and functional thermoplastic prototypes. According to the company, the new board can slash 20% from the production time of core and cavity injection mould inserts compared to traditional methods and materials.
Polymer
Lipid-resistant polycarbonate developed
A new polycarbonate grade is designed for medical products that come into contact with IV fluids. Makrolon DP1-1805, developed by Bayer AG (Leverkusen, Germany), exhibits excellent resistance to stress cracking when it comes into contact with lipid emulsions, according to Johann Thim at Bayer. These emulsions are increasingly used for the intravenous administration of water-insoluble drugs.
The resin, featured at Bayer's MEDTEC stand, withstands EtO and gamma sterilization as well as steam autoclaving at 121°C. Stabilizers in the material minimize the yellowing that is caused by gamma sterilization (the slight discolouration that does occur disappears after time).
According to Thim, Bayer's polycarbonate is destined to replace specialty polyurethanes, polyetherimides, copolyester, and polysulphones in the production of infusion sets. Not only is it less costly than those materials, but Makrolon can be easily and economically processed by meansof injection moulding, he notes. In addition, the polycarbonate grade can be securely bonded to PVC tubing using solvent-containing adhesives. The material's dimensional stability ensures that bonded joints do not come loose, preventing the formation of leaks.
Makrolon DP-1 has been specified for the manufacture of the SAFSITE needle-free injection system developed by B. Braun Medical (Bethlehem, PA, USA). Other suitable applications include tubing connectors, luer fittings, piercing pins, stopcocks, and Y-site medication ports.
Pressure transducers
OEM components offer enhanced performance in harsh environments
A line of pressure transducers combines recent advances in silicon sensor technology and core concept packaging to deliver enhanced measurement performance, even under harsh environmental conditions. 
The new PDCR 4000 series, which was launched by Druck Ltd. (Groby, Leics, UK) at Manufacturing Week, is designed to meet the needs of industrial and OEM users, according to sales support manager Tony Cuttill.
The components feature measurement accuracy up to ±0.04% and greater than ±0.1% long-term stability per annum. Pressure ranges are from 70 mbar to 700 bar gauge or absolute, and 70 mbar to 35 bar differential. Output is rated at up to 100 mV full scale or 200 mV by selection.
The transducer is packaged with signal-conditioning electronics, adds Cuttill, in an enclosure designed for optimal corrosion resistance. It is available with certification authenticating its intrinsically safe operation.
The company holds a wide range of pressure cores in stock, which are completed with performance criteria and pressure and electrical connections to suit individual customer requirements.
White-light sensor
Compact component recognizes markings of any colour
A white-light sensor exhibited at Manufacturing Week can recognize printed matter of any colour against any background hue. In addition, the WMO3PCT2 sensor from Wenglor Sensoric GmbH (Tettnang, Germany) is the smallest of its type, according to the company's marketing director Andrea Spieth.
The teach-in function enables the user to easily set the sensor for normally closed or normally open contact operation, or with pickup or release delay. Two simple keystrokes suffice to align the sensor with the markings that are to be detected and to identify the background, says Spieth. "There is no need to alter the emitted light or change the sensor when you have a new application," she says. "You simply change the settings using the teach-in function."
Flexible containers
Triple-layer medical containers minimize potential for leakage
Designed to replace more-costly glass containers that require cleaning under strict hygienic conditions, disposable pouches that comply with USP Class VI guidelines are produced by Lider S.A. (Montrevel-en-Bresse, France). Primarily made of EVA, the pouches are available in capacities of 10, 20, 50, 100, 150, and 200 L. "One unique aspect of these bags," says company president François Bonnier, "is that we can incorporate two or three layers of EVA into the pouch to virtually eliminate potential leaks." To ensure zero-defect products, Bonnier adds, each pouch is subjected to a burst test.
Also on display at the company's MEDTEC stand was a device with an embedded chip that can be integrated into packaging that requires precise traceability. "The chip generates an ID number that will enable software to recognize where it has been and where it is at any given time," says Bonnier. "It works like a bar code and is suited for blood pouches or indeed any product that would benefit from complete and reliable traceability." The advantage of the chip over a bar code, Bonnier adds, is that it generates an identifier unique to each product. In addition, it is welded into a waterproof pouch to ensure readability. "Bar codes, when they are wet, cannot be read," says Bonnier.
Lider's core activity is high-frequency welding, and the company supplies a variety of medical consumables to device OEMs, including drainage, urine, enteral, and infusion bags; tubing sets; IVD products; and lay-flat tubing and foils. The manufacturing facility is equipped with a Class 100,000 cleanroom; high-frequency welding can be performed under a laminar-flow hood to attain Class 100 conditions. Printing services are also available.
Colour monitors
Displays deliver CRT-quality image in ultrathin package
Developed by a company that holds more than 360 patents, field emission displays (FEDs) combine the visual advantages of phosphor-based imaging found in cathode ray tubes with the convenience of flat panels as thin as 2.4 mm. Because they feature natural viewing angles and a 20-microsecond response time, and consume 30% less power than LCDs, the monochromatic displays produced by PixTech S.A. (Rousset, France) are popular with device manufacturers. The company recently signed an agreement to ship 50,000 units to a US maker of medical equipment. At MEDTEC, the company previewed its next generation of FED modules that offer comparable performance specifications in a colour display.
"The final thickness of the module, which includes the filter, screen, mechanical parts, driver, and dc/dc converter, will be 13 mm," says marketing manager Jean-François Gros. The driver, he adds, was developed specifically for the FED process to permit lower power consumption and better image quality. "We have found that low voltage is the way to go. Image quality is just fine, but it substantially reduces the cost," says Gros.
The FED tube itself is a 2.4-mm-thick vacuum enclosure composed of two plates. One plate supports a matrix array of microtip electron emitters; the other is coated with RGB phosphors that emit light under bombardment of accelerated electrons.
The module accepts a full range of digital and analogue interfaces, including VGA, RGA, and LVDS.
Do you have a Showstopper?
If you will be launching a new product at an upcoming exhibition and would like to be considered for coverage in the Showstoppers section, send a fax to the editor at +1 310 4454299. You may also mail the information to Showstoppers, EMDM, 11444 W. Olympic Blvd., Ste. 900, Los Angeles, CA 90064 USA.
Shows that EMDM editors will be attending in 1999 include MD&M West and East, Hannover Fair, Sensor 99, Europlast, Italmedica, and MEDTEC.
