Heavy plastics for that quality feeling

While plastics are typically selected because they are lighter than metals, some applications in the cosmetics and personal care market prefer using materials that are heavy to simulate the feel of metal. Clariant Masterbatches Specialty Compounding (McHenry, IL) will introduce a product to meet these needs at the HBA Expo, held in New York this month.

Called “heavyweight” compounds, the specific gravity of these new products can be varied from as low as 1.5 (similar to plaster of Paris or ceramic tile) to 11 (approximately that of lead) depending on which high-density filler is selected. These include tungsten, barium sulfate, and bismuth, and they are used to fill a wide range of thermoplastic resins, from polyolefins, nylon, and PVC to ABS and other engineering plastics. Many formulations can be custom colored (depending on the filler and loading level), relying on Clariant’s core competency in this area.

“Metal has gravity or ‘heft,’” explains Peter Prusak, head of the North American packaging market segment for Clariant Masterbatches. “In a bottle top, a lipstick tube, or a compact case, that heavy feeling suggests quality, durability, and value. This impression can be very important in the marketing of personal care products. But metal parts are often time-consuming and costly to produce, especially in complicated shapes, so designers increasingly turn to plastics for design flexibility, manufacturing ease, and cost benefits. Now, with these new heavyweight compounds, they can get the best of both worlds.”