Henkel and 4Jet described their process as a "tailor-made acoustic foam … produced directly inside the tire from liquid starting materials."
This method, they state, eliminates complexities related to the current procedure, which quite often involves a second, parallel logistics line that transports the lightweight but high-volume foam to a spot near the end of the production line, where the foam is installed, often by hand.
This process requires substantial space for logistics handling and multiple stages of intermediate storage for the foam, Henkel and 4Jet said, as well as numerous additional manual or semi-automatic steps for logistics, cutting, adding adhesives and inserting the foam into the tire.
These additional steps can inflate the cost of a tire by up to 25%, the partners said, as well as generate significant volumes of waste from the off cuts of the polyurethane foam pieces.
The technology, Henkel and 4Jet said, also provides tire makers greater freedom in adapting the "foam's geometry and volume" to the tire type and thereby reduce waste generation and help lower a tire maker's carbon footprint.
This direct foaming process — which is used already in other industries and applications — is made possible by a patented foam-activation process using a laser after the foam has been applied.
Henkel's contribution to the process is the Loctite Laser-Fit acoustic foam, which achieves effective sound absorption through a large inner surface and pore design, according to Rainer Schönfeld, global market strategy head in Henkel's Automotive Component business unit.
Once a layer of foam is installed and it expands, the foam's skin is removed by a laser-activation process developed by 4JET, exposing the foam's open-pore structure, which is effective in absorbing sound.
This direct foam-to-tire technology represents a "joint commitment to innovation and sustainability," George Kazantzis, global head of Henkel's Automotive Components business unit, added.
Dusseldorf-based Henkel is a developer and producer of adhesives, sealants and functional coatings for a range of industrial applications as well as for consumers and craftsmen.
Alsdorf-based 4Jet Technologies designs and builds integrated machine solutions for industrial production by combining laser-process technology, optics, machine vision, automation and software. It's known in the tire industry for its laser-based mold-cleaning process/technology and tire sidewall engraving/marking.
