Injection molding of small medical parts continues to grow, but the terms ``micro'' and ``nano'' raise hackles.
The development of technologies in the medical field makes ``the future for micromolding look great,'' said Stu Kaplan, president of Makuta Technics Inc. of Columbus, Ind.
``New developments in medical applications lead to new developments in production technology [and] in turn new developments in medical applications,'' Kaplann said. Advances are being made in screw tips, feeders, robotics and materials, he noted.
Darrel Hill, national sales manager with Boy Machines Inc. of Exton, Pa., said that during 2004, there has been a sales increase of about 50 percent in the medical micromolding market, especially for vertical presses.
In response to increasing interest, the Society of Plastics Engineers is looking at forming a nano/ micromolding special interest group. ``We are filling out the steering committee and writing a scope [of purpose],'' said SPE member Dan Buckley, director of product development with C.A. Lawton Co.'s machinery division.
Scott Herbert, president of Pleasanton, Calif.-based Rapidwerks Inc. said that original equipment manufacturers have an interest in working with micromolders ``to build next-generation products.'' Over the past decade, molding technology has changed significantly with servomotor-controlled injection, metering and plunging systems and smaller shot sizes, he said.
``The influence on a molding machine is tremendous,'' permitting positional accuracy to submicron tolerances, Herbert added.
Domestic molders have an advantage
``Medical devices in the micro and nano arena are less likely to be built offshore due to proprietary technology reasons,'' said Dennis Tully, vice president of engineering with Miniature Tool & Die Inc. of Charlton, Mass.
Tully said the refinement of part design is a processor's ``most important first step.'' Players in the medical field seek ``smaller, less invasive products, which should lead to more product development,'' he said.
Michael Santa, president of press maker Battenfeld of America Inc., said, ``We are seeing the need for smaller components as the medical industry evolves.''
Battenfeld micromolding inquiries - mostly for medical work - increased more than 30 percent last year vs. 2003, Santa said.
Since 2000, Battenfeld, based in South Elgin, Ill., has sold more than 70 servo-driven Microsystem 50s. Now in its third generation, a basic system costs $200,000-$500,000 and can cost $1 million with a sophisticated mold.
Battenfeld documents the production of a hearing-aid part weighing 22 thousandths of a gram. ``At that point, you are into nanomolding,'' Santa said.
About 95 percent of product developer Medical Murray Inc.'s efforts involve medical work, according to Brent Roland, sales and marketing director. Medical Murray, in Buffalo Grove, Ill., licenses manufacturing, sales and service of its Sesame injection molding machines to Lawton's machinery division.
Lawton engineers in De Pere, Wis., designed the third-generation Sesame press in early 2004. Its clamping force is 3,000 pounds.
``In order to fill very small cavities and features, the Sesame is designed for injection pressures up to 50,000 [pounds per square inch] and theoretically can inject the full shot length in as little as 0.048 second,'' Buckley said.
Terms of debate
Accumold Corp. of Ankeny, Iowa, takes a dim view of others using its registered trademarks on terms such as Micro-Mold, Micro-Molder and Accu-Molder.
The firm is ``in micro, submicro, supermicro and now nano'' molding, said Roger Hargens, chief executive officer and president. An Accumold expansion may see military and aerospace become one-half of its business, up from 10 percent. The firm, which also serves the medical market, operates 37 proprietary Micro-Mold presses and 32 conventional machines of 12-30 tons.
``[Micromolding] is really a new word for the same old thing - making small parts,'' said Jrgen Giesow, regional sales manager in Huntington Beach, Calif., for Arburg Inc. Whether the process will be called micromolding or small-part molding remains an open question in his mind.
``A true micromolding part needs to be robotically removed out of the mold because it is too light to actually drop,'' he said.
``Nanomolding is a buzz word only,'' and defining micromolding depends on what a person thinks a microsize part should be, said Ron Peterson, vice president of Micromold Inc. of Riverside, Calif.
``Molds are vented to around .0005 inch, [and] a nanometer is a factor of 12,820.5 times smaller,'' Peterson said. Micromold makes small detailed parts, many for medical applications.
``No true nanomolding takes place,'' said Chris Kightlanger, a Toshiba engineer. ``We cannot even machine to nanomolding technologies.''
Kightlanger said he is aware of polymers that contain nanotubes for strength, but he dismissed the use of the term nanomolder.
``I think it is a misrepresentation of the technology,'' he said. ``They give the illusion they are molding to the ninth power and actually [they are] not.''