Laser-Markable ABS in Innovative Cable-Tie Tool
WEB EXCLUSIVE: A laser-markable, glass-reinforced ABS was customized to meet tensile strength and printability requirements of an innovative cable-tie tool from HellermannTyton, Milwaukee. The compound was developed for this application by RTP Co., Winona, Minn.
The OEM gave the green light to custom injection molder New Berlin Plastics, New Berlin, Wis., to work with RTP to tailor the compound to be strong enough for the small teeth on the tool’s plastic tension knob and to be imprinted with a graduated number scale. New Berlin’s business development manager, Dave Sansone, and director of engineering Mike Miller had worked with RTP many times in the past and knew of the company’s ability to create laser-markable plastics that could suit this application far better than other technologies, such as in-mold decorating or preprinted adhesive stickers, that were first considered by the OEM. Says Miller, “Laser-marking the numeric scale was much better solution, avoiding the time-consuming challenge of printing, the high scrap rates that would have been associated with in-mold decoration, and the physical challenge of precisely affixing a small, 0.25 in. wide sticker.”
After careful testing and evaluation, RTP furnished a custom glass-reinforced RTP 600 Series ABS compound that provided the required tensile strength for the cable-tie tool’s tension knob. A matched RTP 6042 Series TPE compound—formulated to bond with the rigid ABS substrate—was then overmolded onto the knob to provide an ergonomic gripping surface. RTP colorists added laser-marking additives and colorants chosen for their compatibility with the ABS compound and the operational range of the laser being used. This allowed the laser to “write” an indelible, high-contrast white mark on the black plastic surface—marking that will hold up for the life of the product.
Though often criticized, MFR is a very good gauge of the relative average molecular weight of the polymer. Since molecular weight (MW) is the driving force behind performance in polymers, it turns out to be a very useful number.
Plastics weigh in with added design freedom and environmental friendliness—especially when the alternative is lead.
After molding, acetal parts can continue to shrink at room temperature and even in the cold.