OPPORTUNITY: Molding "soft-touch" TPEs.
GROWTH OUTLOOK: Thermoplastic elastomers (TPEs) are the new materials of choice for many European toy makers, who are being forced by legislation to get PVC out of their products. So says Annalisa Gigante, market manager for the consumer sector
First used in toys as a replacement for PVC car wheels, TPE uses have expanded to include "soft-touch" applications such as interactive learning toys for infants that teach letters, numbers, and textures. Two large European toy makers, Lego of Denmark and Playmobil of Germany, are among the first to use the materials.
MATERIALS USED: A variety of olefinic and other TPE's.
PROCESSING SKILLS: Soft-touch applications involve multi-component injection molding. The soft TPE can be joined to rigid polypropylene in an overmolding process. Or, a special machine can be used for a two-shot method in which the mold first receives the PP, then one half rotates 180 [degrees] to mate with a different cavity half designed to receive the TPE.
OPPORTUNITY: Gas-assist injection molding.
GROWTH OUTLOOK: Gas-assist molding for one U.S. toy maker has resulted in 3096 material savings, more stress-free parts, and ability to use a smaller machine, which reduces molding costs and floor space. Foxx River Co. Inc., Attleboro, Mass., uses 600-ton presses and nitrogen gas-assist technology from Gain Technologies, Sterling Heights, Mich., to produce a 4-ft sled and a "walker buggy" for infants. The 750-sq-in. sled would have required a 1500-ton press without gas assist, says Eric Carter, Foxx River's director of engineering. The sled, made for the past two years for Paris Co. Inc., Oxford, Maine, is surrounded by a 0.5-in.-diam. tubular handle produced with gas assist. The walker buggy is a new toy introduced this year by Safety First of Chestnut Hill, Mass. Production of the sled increased 25% over the past nine months.
MATERIALS USED: Polypropylene with a nitrogen gas-assist.
PROCESSING SKILLS: Successful gas-assist molding requires some experience with the technique, which has several variations. Foxx River uses two approaches - gas injection through the machine nozzle and through mold pins. Proper part and mold design is critical. Particular attention must be paid to gate location. "You have to think of the gas assist as a second injection process and design accordingly," says Carter.
OPPORTUNITY: Small toys molded of engineering TPs.
GROWTH OUTLOOK: Child safety is the reason engineering thermoplastics are being used in small, solid toys, say two U.S. firms that employ such high-end materials on a large scale. They say these resins' mechanical strength, non-brittleness, and memory retention after bending outweigh their typical 400% price premium over commodity resins.
The Rodon Group, Hatfield, Pa., maker of K'Nex construction toys, plans to triple purchases of acetal resin in the next three years to about 15 million lb/yr. Likewise, Discovery Toys of Livermore, Calif., a producer of Boomering Links, will raise its acetal consumption from 55,000 lb to 65,000 lb/yr. "We are willing to sacrifice profit for a more durable product," says Greg Thomas, director of quality assurance. High-strength resins also make downgauging possible. Both toy makers are using Celcon acetal copolymer from Ticona Corp., Summit, N.J.
MATERIALS USED: Acetal, nylon, ABS.
PROCESSING SKILLS: These materials tend to be molded with tolerances as tight as [+ or -]0.001 in. Stainless-steel molds may be required. Proper gate placement and mold temperature are critical to avoid stress and flow marks.