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August 3, 1998

8 Min Read
Communications Technology

Not surprisingly, the key phrase in this market is "cell phones." Cell phone and digital phone manufacturers, molders, and material suppliers are seeing dollar signs in the growth potential this market holds (see chart). However, there's more to this market than mobile phoning. Every cable TV system and cellular and digital phone system needs an infrastructure to support it, and the potential there is just as enticing.


Outdoor Infrastructure

Joel Fouquart, technical manager in the marketing group for telecommunications at GE Plastics, says short-term growth can be found in the portable market. But one of the biggest focuses of his group is on the outdoor infrastructure segment. This includes cable subscriber boxes that are attached to or near a customer's house and cable amplifiers. These typically diecast units show a potential for metal replacement.

Fouquart says that for subscriber enclosure applications, the material must be able to survive a 5 ft-lb impact at -40F. For cable amplifiers the material requirements are tougher and it must survive a 100 ft-lb impact at -40F. For both applications, as usual, the drivers are reduced cost and reduced weight. Also a big consideration for these applications is heat dissipation. Internal components last longer and perform better if kept below 176F. The key is to design
boxes that maximize the performance of all-plastic parts that optimize heat management. For low- and medium-power applications, all-plastic boxes are OK. High-
power boxes, however, will most likely require hybrid designs combining aluminum and plastic.

Also outside are hybrid coax-fiber optic boxes, also called active network interface devices. The potential here is good, but Fouquart says this segment is slower to mature. "A couple of years ago we were more excited about the potential of this segment, but we're now beginning to see the growth we expected," he says.

Inmold Product Differentiation

Dan Bennett, industry manager for film at GE Structured Products, has been focusing on inmold labeling and points to product differentiation as the key for molders and OEMs looking to make gains in this market. "You want to make a cell phone that stands out in a sea of cell phones," he says. Processes to do this include inmold decoration and overmolding. Bennett says he's currently developing inmolded lenses, bezels, and keypads and expects a 20 percent growth in telecommunications in 1999.

On the horizon is this interesting concept: Inmold shielding. Bennett says GE is still developing products for this technology, but the concept is simple. Mold a shielded film over the base material, eliminating the need for postmold treatment, such as painting or plating. "This technology would displace or replace the typical method for shielding," he says.

Inherent Shielding

Bypassing traditional shielding altogether is inherent shielding. Carbon fillers in resin provide built-in shielding for the part. Fouquart says GE transferred lessons learned on this process from the laptop computer market and expects to see inherently shielded communications products beginning in 1999.--Jeff Sloan

Motorola phone takes advantage of inmold decoration


The familiar dog tag worn by members of the U.S. armed forces is stepping quickly into the next century. Replacing the well-known tag may be a plastic tag encapsulating medical records stored on a memory chip.

Called the Medi-Tag, the new record carrier was developed by Data-Disk Technology Inc. of Sterling, VA. It consists of a flash memory chip surface-mounted on an integrated circuit (IC) board. The chip is read and updated by inserting it into a slot in a standard PCMCIA reader on a PC. It can store up to 20 megabytes of data, including a medical and x-ray history, allergy information, dental records, and other information.

Encapsulating and protecting the chip is a Zytel nylon from DuPont. "The reliable, long-term protection provided by Zytel nylon is crucial to the tag's reliability as a permanent record," says Tom Clark, president of Data-Disk. The nylon is a glass-reinforced 612 grade injected in a slow, low-pressure process to avoid damaging the tag's delicate circuitry.

Using encapsulation techniques developed by DuPont, the nylon achieves a complete, hermetically sealed shell to block penetration by dust and fluids. The material also provides protection against impact damage, other mechanical loads, and abrasion or chemical corrosion by skin oils.

Clark reports that the tag has performed well in Dept. of Defense tests and is a "leading candidate for a $40-million contract involving field testing of a personal information carrier by the armed forces in 1998 to 1999." The military's ultimate goal is to issue personal data carriers to all members of the armed forces and reserves. Another possibility is use by retiring military personnel and dependents.

For more information:
DuPont Engineering Polymers
Phone: (800) 441-0575
Circle 240

Memory chips get nylon protection


The new line of StarTac portable cellular phones from Motorola uses inmold decoration provided by ARC Global Technologies, a Chicago-based company, to produce keypad labeling that is virtually indestructible.

Unlike most inmold decoration applications, for the ultracompact StarTac, Motorola and ARC decided to use a transparent polycarbonate with the keypad label printed on the back side, or second surface. This means that on injection the molten resin comes in direct contact with the preprinted label in the mold, which could crack, fade, or "wash out" the printed image. But, if done successfully, it also means that the label is secure behind the polycarbonate film and the user's dialing fingers never come in direct contact with the keypad label, eliminating wear.

The film chosen for the application is GE Plastic's Lexan polycarbonate. Printing on the back side requires special inks and a printing process that minimizes cracking. The keypad can also be backlit for low light applications.

ARC Global Technologies has developed an inmold labeling process called Permagraph, which uses an applicator robot to insert labels into the mold. The system works from the top of the fixed platen and loads labels from a magazine into the cavity of the mold. The loading robot is linked to the press's emergency stop signal to prevent the mold from closing on the robotic arm. The subsurface printing technique developed by ARC is called Polymac.

For more information:
ARC Global Technologies
Phone: (800) 654-3662
Fax: (312) 201-1412
Circle 238
GE Plastics
Phone: (800) 845-0600
Fax: (800) GE FAXBACK
Circle 239

Cell phone holster keeps calls at hand


Vista, CA-molder Co-Mack Technology teamed up with an OEM to produce this cell phone holster, taking the product from concept to market in less than nine months. The OEM was looking for a way to keep the unusually small phone close at hand. The holster that resulted can be clipped to a belt, purse, or briefcase, similar to a pager. Time was critical, as the phone itself was already on the market. "Our challenge was meeting the OEM's requirement for a product with an appealing and functional design at a cost-savings point," says Joseph McRoskey, CEO of Co-Mack.

Co-Mack and the OEM refined the criteria for the holster, which also holds a spare battery for the compact phone that measures 3.6 by 2.4 by 1 inches. The holster had to have the strength and integrity to protect the phone and the battery from each other and from the bumps and impacts of everyday use. The prototype design called for a thin wall separating the battery from the phone. In just eight weeks production tooling was completed for the part, and within 12 weeks the first prototypes were produced at Co-Mack's 74,000-sq-ft facility. Prototype testing showed that the holster, as designed, could not hold the phone if inverted, and placing and replacing the phone in the holster created a chalking effect on the holster material, a PC/ABS.

Minor tooling modifications were made to help the holster hold the phone, and Co-Mack added a polytetrafluroethylene (PTFE) to reduce the coefficient of friction of the PC/ABS and eliminate the chalking. "Troubleshooting is part of the game in completing projects to ensure functionality before allowing the product to hit the market," says Tom Marsh, COO of Co-Mack. "Our engineering, manufacturing, and quality teams work side-by-side from concept to design and modifications, on up the production ramp."

For more information:
Co-Mack Technology
Phone: (760) 599-5100
Fax: (760) 599-4553
Circle 241

The DynaMyte is a portable device that helps people with speech, language, learning, and physical disabilities communicate in almost any social or business situation. Manufactured by Sentient Systems, this computer-based device helps people with these disabilities express themselves using software and a 42,000-term vocabulary that transmits a customized personal voice.

Because the DynaMyte is portable and therefore subject to daily bumps and bruises, surrounding the internal components with a durable case is vital. Color matching different materials for aesthetic consistency is also important. The RTP Co. worked with injection molder Prototype Products to help match colors in high- and low-gloss resins.

A glossier precolored PC/ ABS alloy is used for the housing and legs and requires a match with a low-gloss flexible thermoplastic elastomer (TPE) used in the rubberized feet. To compensate for differences in light reflection, technicians impart a richer, deeper color to the low-gloss TPE. The PC/ABS blend supplied by RTP has an Izod Impact at 73F of 10 ft-lb/inch and a tensile strength at yield of 9100 psi.

In addition, the DynaMyte device also operates as a control center for household appliances using infrared light beamed through a visibly opaque protective cover. A precolored
infrared-transparent polycarbonate was selected for the
application and tested on a spectrophotometer to ensure the compound meets tight infrared wavelength tolerances. For more information:

The RTP Co.
Phone: (800) 433-4787
Fax: (507) 454-2041
Circle 242

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