Quiet, light, and durable
Weight optimization in vehicle construction and the resulting reduction in sheet-metal thicknesses require customized high-quality materials for all body sound damping and localized panel reinforcement—and these are precisely the core skills of Dr. Freist Automotive GmbH.
Our product portfolio is divided into three categories ranging from pure acoustic dampening sheets to hybrid materials for sound deadening and simultaneous reinforcement to high-performance reinforcement sheets for local sheet metal panel reinforcement. Thanks to our in-house formula and equipment development and process engineering, we are able to develop and prepare a customized solution for every application that conforms precisely to the wishes of clients.
Dampening – attractive in every application
Our classic product is our bitumen-based dampening sheet. Bonded with bitumen and enriched with acoustically effective filler, this material comes to application in nearly every vehicle, thereby considerably enhancing its acoustic comfort. Depending on the assembly site, our materials come equipped with either with hot-melt or special pressure sensitive adhesives, and can also be vertically applied by magnetic adhesion. These sheets thus meet all requirements for process reliability, temperature resistance, acoustic performance, and the high standards of emission performance. Beyond that, they can take on virtually any desired shape.
Dampening and reinforcing – when it simply has to be light
It is here that we develop the perfect combination of hybrid materials. On the basis of various designs, high acoustic performance capacity can be combined with a reinforcing effect. With our lightweight foam sandwich, surface weights of well under 2 kg / m² can be achieved while at the same time allowing for reinforcement by way of a covering layer of aluminum or special cardboard. Many of our customers have approved a structure of 0.8 kg / m² for installation in their vehicles. The aluminum-bitumen sandwich represents a cost-effective and smarter alternative to aluminum-butyl designs, as the very same acoustic performance can be achieved without the familiar disadvantages of cold flow, for example. Depending on the choice of adhesive, applications are possible in body-in-white, paint shop, or as a component in general assembly. The clever combination of bitumen sheets and reinforcement sheets delivers a product that combines the advantages of both materials into one. Expanding bitumen sheets are considered a specialty of Dr. Freist Automotive GmbH. These not only offer high acoustic performance by filling cavity spaces, but also offer an additional stiffening effect between two body panels.
Reinforcement – stable, lightweight, and vibration-free
Our stiffening sheets are the optimal reinforcement. For local panel reinforcement, our materials can be deployed in two ways: either with fiberglass as a laminate for invisible reinforcement of thin external panels, or as a stamped panel without fabric that provides both static and dynamic support to the panel structures within the body. These sheets, which are flexible and easy to manipulate in their delivered state, acquire their final strength when passing through the paint oven in the paint line. Equipped with various adhesive superstructures, bonding processes to various substrates are possible either during general assembly, in the paint line, or in the body shop.
GKD adhesives – bonds that last
Our in-house adhesives ensure long-lasting hold. Our subsidiary company’s (GKD) self-developed Hotmelt ensures a safe and durable bond between our heat-activated sound damping materials and the body. In so doing, we effortlessly master all the requirements of temperature stability and thermal state, both during the process as well as in the low-temperature stress of daily use. This Hotmelt adhesive is also produced by GKD in Goslar.