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Formable Luminescent Films Can Be Backmolded

Polycarbonate electroluminescent films can provide light in homes, cars, cellphones, and even inside ladies’ handbags. While it has been possible to make flat light-emitting films, they now can be formed into 3D shapes with tight radii, thanks to technology developed by Lyttron Technology GmbH, a new start-up subsidiary of Bayer MaterialScience AG in Cologne, Germany. Lyttron uses screen printing to deposit the electroluminescent structure--essentially a parallel-plate capacitor comprising up to 20 layers--on Bayer’s Makrolon PC film. Lyttron uses back-side printing to protect the special layers from damage. When connected to a source of electric power--mere millivolts--the structure emits light without heat. The entire surface of the film emits light uniformly. No diffuser sheet is needed. The coatings can emit light in blue, green, orange, or white, and can be printed on matte or glossy surfaces.

            Lyttron developed a high-pressure forming method for 3D lighting shapes. The formed film can be used as an in-mold decorating insert and backmolded by injection molding. Lyttron’s first application was a strip for illuminating the inside of women’s handbags. Also commercial is a self-lighted car license plate. Tel: +49 214 30 46274, www.lyttron.com

‘Hybrid’ Induction Barrel Heating Pays Off Even Faster


Xaloy Inc., New Castle, Pa., has come up with a more economical “hybrid” version of its nXheat induction heating system for injection machine barrels (previously named Indx). It combines power-saving induction heating in the feed zone with conventional heater bands in the downstream zones. The new nXheat-Hybrid version costs only 25% to 50% as much as a complete nXheat system. That provides faster payback and makes the system practical for smaller presses.

As we reported in September, nXheat consists of sheet insulation wrapped around the barrel and induction heating cable that is wound in a spiral over the insulation. Current through the cable induces eddy currents in the machine barrel, heating it internally. This approach costs about five times as much as the initial cost of band heaters but consumes up to 70% less energy. Induction heaters also last much longer and provide more uniform heat, Xaloy claims. The company said induction heating on a machine with screw diameter of 50 mm or more (i.e., 400 tons or larger) could pay for itself in as little as 18 months, depending on energy cost, cycle time, and operating hours.

            The nXheat-Hybrid version is best suited to smaller machines with two or three barrel zones, on which it typically uses 30% to 50% less power than a barrel with heater bands alone. Even greater savings are said to be possible by using the same sheet insulation as in the feed zone to cover the downstream band heaters.

Micro-Molding Press for LSR Debuts

A new press for molding micro-size parts from liquid silicone rubber comes from Engel Canada, Guelph, Ont. The tiebarless press is based on Engel’s e-Victory 80/30 hybrid-electric system, but features a special 12-mm LSR screw and check-disk assembly, as well as a special platen that can hold small or large mold bases. The electric injection unit can run shots from fractions of a gram to 55 cc with a simple barrel and screw changeover. The machine also comes with Engel’s basic cleanroom package featuring stainless-steel panels and other components.

            A six-axis robot from Kuka Robotics (Clinton Township, Mich.) is integrated within the machine footprint for parts removal and inspection. A small-shot LSR dosing system from Fluid Automation (Wixom, Mich.) is mounted directly on the feed throat.

Microspheres ‘Insulate’ Blown Film

A half-dozen processors in the U.S. are testing small amounts of polyacrylonitrile microspheres from Akzo Nobel’s Expancel Div. in Duluth, Ga., to make paper-like films that insulate hot food. Tests include one-, three-, and five-layer films with Expancel loadings from 0.25% up to 3.5%. The higher loadings make film cloudy and also double its thickness. Applications under market testing include shrink wrap for hot carryout foods. Very low loadings in the middle layer of a three-layer film result in slight surface bumps, which impart anti-block properties. Three blown film products containing Expancel are in market testing now.

Partially Open-Celled Foam Is a First

Seksui Alveo AG in Switzerland has developed what is believed to be the first partially open-cell crosslinked polyolefin foam in roll form. Partially open cells allow the foam to compress easily without being porous to air or moisture. The product is designed for sealing tapes to insulate buildings and stop drafts and seal ventilation ducts. It’s been marketed for about a year as Alveo-Soft.

The technology is described in the patent application (U.S. Pat. Applic. 20080003421) as taking the crosslinked foam sheet and compressing it between rollers to rupture some of the bubbles. The level of rupture or softness can be controlled. Sekisui Alveo makes both PE and PP Alveo-Soft foams and offers four levels of softness from 0.7 to 5.8 psi compressive strength at 50% compression. Tensile strength is 36 psi. Water absorption is at most 2%. The product is extruded up to 2 meters wide and 2 to 12 mm thick and can be laminated to achieve other thicknesses or levels of softness. Tel: +41 (41) 228-9292, www.sekisuialveo.com