The timberlands of eastern Finland have given birth to a new group of injection moldable, natural-fiber-reinforced thermoplastic composites for which its developers are trying to find fresh global markets.
Kareline Oy Ltd. is a nine-person firm in Joensuu, Finland, about 30 miles from the Russian border. In a small booth at K 2007, held Oct. 24-31 in Dusseldorf, export manager Tony Lindqvist explained that the company was founded in 2001 and gained some funding from the city and local university to advance development of the plastic-based compounds that can take wood-fiber weight loadings ranging from 20-55 percent.
The firm, working with an industrial designer and with research and testing help from the university, developed a process to separate the wood fiber from the cellulose mass, and then chemically and mechanically bond it to the thermoplastic substrate.
Kareline primarily uses polypropylene and ABS resins, but also can produce compounds using polyethylene, polystyrene and even biodegradable polylactic acid.
Lindqvist said Kareline spent ``two to three years to get it right.'' It began commercializing some compounds in 2005 and now has patents pending on the resulting process. Its compounds - which require pre-drying and are limited to processing at temperatures no greater than about 410° F - can run on standard tools and presses. Users also can apply typical post-processing methods to the parts, including ultrasound welding, machining and laser marking.
Though its materials also can be extruded, the firm decided early on to focus on injection molding, since the volumes for most wood-plastic composites are in extrusion for such products as decking and fencing. As a result, Lindqvist claims, Kareline currently has no serious competitors in the injection molding space. But is also needs to work twice as hard to get its message out about possible applications.
The company suggests uses such as indoor/outdoor furniture, tool handles, household products, appliance covers, technical or molded automotive or electronic parts, and even cosmetics or jewelry packaging.
But the eye-catching applications at K 2007 were none of the above. Kareline displayed a hollow-bodied electric guitar and unfinished, green-swirled, solid guitar body.
The guitars, handmade by Finland's Flaxwood Oy, deliver quality sound due to the finely honed wood component of the compounds.
Lindqvist would not describe the polymer matrix used with a 50 percent wood-fiber loading to produce the guitar body and neck, other than to say it was a ``thermoplastic blend.''
Gordon Roberts, president and chief executive officer of Flaxwood USA Inc. in Bowie, Md., said the firm is poised for a major North American marketing push.
``So far we are just getting ourselves situated in the U.S. market,'' Roberts said via e-mail. ``As of today, we have sold just a handful of guitars here in the States but that will change rapidly in the coming months. The pricing runs from about $1,600 for the lower-priced models to $2,800 for the top-of-the-line guitars. We are also offering custom shop guitars that can be modified to the customer's taste.''
The guitar company's Web site explains its genesis. ``The brainchild of Heikki Koivurova, an industrial designer from Joensuu, flaxwood was born out of a desire to create an environmentally friendly, recyclable wood-based material to substitute for the exotic tone woods normally used in building instruments.''
Veteran instrument builder Veijo Rautia, a master luthier with decades of experience in handmade guitars, convinced Heikki to research what the new material could do for the electric guitar.
``As the experiments progressed,'' the site said, ``a wealthy local industrialist and former saw milling magnate offered to put up some venture capital to take matters further. Antti Vilenius also came on board with years of specialized mold-injection production experience. After two years, a new tone material was ready to be introduced.''
(To listen to sample sound clips of Flaxwood guitars, go to www.flaxwood.com, select ``Models.'' Click on one of the guitar models and scroll to the bottom of the page.)
Kareline notes that its compounds offer minimal shrinkage and an absence of sink marks during processing, which it says can translate into simpler mold and product design. The materials also provide design freedom.
For example, Kareline composites can be used to mold extremely thick walls, or can vary widely in wall thicknesses - from fat to thin - in a single, injection molded piece.
The materials also yield products that are strong and stiff, with none of the problems (e.g. mold wear, weld lines, etc.) associated with processing glass-fiber-reinforced resins. Finally, Lindqvist, noted, his firm's compounds yield products with a varied surface structure that gives an impression of depth and warmth.
Other applications include Kupilka drinking vessels, Fenron-brand, porthole-style windows that offer good thermal insulation properties, and a pair of chopsticks that can be reversed to form a fork.