Innovation with adhesion compound from KRAIBURG TPE

THERMOLAST® A makes assembling roof rail covers easier by integrating the seal using multi-component injection molding

KRAIBURG TPE offers a broad range of thermoplastic elastomers (TPEs) for interior and exterior applications, as well as applications for engine compartments and power trains of motor vehicles. Gutsche Engineering – specialized in sophisticated vehicle components – also relies on the TPE manufacturer from Waldkraiburg, Germany, in producing its innovative roof rail cover. Gutsche Engineering has benefited from the cost-effective processing and above all from the outstanding weather resistance combined with cohesive ASA adhesion in KRAIBURG TPE’s THERMOLAST® A compound for this application.

The component innovation from Gutsche Engineering provides a completely assembled cover with integrated seal for areas where the seal previously had to be mounted under the roof rail in a costly process. Simplifying the assembly process with the OEM is only one of the advantages that multi-component parts provide. The THERMOLAST® A compound from KRAIBURG TPE has enabled Gutsche Engineering to bond ASA and TPE in multi-component injection molding.

“We were looking for a TPE for the seal that can be molded directly onto the ASA hard component of the cover and will ensure permanent and reliable adhesion to this copolymer,” explains Martin Gutsche, managing director of Gutsche Engineering. “Another decisive factor was the TPE’s viscosity, which makes it possible to implement the thin sealing lip geometry without imprints on the hard components by using the lowest mold cavity pressures possible. Along with tool technology and the molding concept, the TPE’s processing and product properties also played a significant role in achieving the required component quality.”

Due to successful collaboration on previous projects, Gutsche Engineering brought KRAIBURG TPE into the development of the application at an early stage in order to identify the TPE that would be most suitable for the innovative application. “In order to determine the adhesion of the various material combinations depending on different processing parameters, we at KRAIBURG TPE offer the service of performing specific tests to check peeling resistance in accordance with the specifications of the VDI 2019 standard,” says Matthias Michl, expert for window encapsulations, covers and frames at KRAIBURG TPE in Waldkraiburg. “We know from past experience that including partners in projects at an early stage and the related preliminary tests can make a decisive contribution to minimizing development costs and advancing the product launch.”

In addition to established adhesion to polar thermoplastics, the chosen THERMOLAST® A compound features high flowability, which allows filling molds for complex component geometries. The main requirements for the roof rail covers also included high weather resistance, as the covers are mounted at the highest point on the vehicles.

The THERMOLAST® A compound used was not only able to meet the high OEM requirements involving two year-cycles of weathering in accordance with PV 3929 and PV 3930 standards in advance, by achieving > level 4 on the gray scale, but it also proved its value on the component during outdoor weathering. Thanks to its excellent weathering resistance and despite a thin seal lip geometry, the THERMOLAST® A compound passed the outdoor weathering test without cracking.

The application implemented with THERMOLAST® A has been in mass production as part of a roof rail system for a premium SUV since the first quarter of 2019.

“Exterior covers are applications that are becoming an increasingly important part of KRAIBURG TPE’s business. KRAIBURG TPE is further expanding its portfolio to meet the growing demand for high-quality surfaces combined with polar adhesion and high weather resistance. KRAIBURG TPE is setting new standards in exterior applications with new compounds that above all provide a precise surface texture in combination with improved adhesion to PMMA and ASA,” Matthias Michl adds.

Reader enquiries

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Notes for editors


KRAIBURG TPE ( is a global manufacturer of thermoplastic elastomers. From its beginning in 2001 as a subsidiary of the historical KRAIBURG Group founded in 1947, KRAIBURG TPE has pioneered in TPE compounds, today being the competence leader in this industry. With production sites in Germany, the U.S., and Malaysia, the company offers a broad range of compounds for applications in the automotive, industrial, consumer, and strictly regulated medical sectors. The established THERMOLAST®, COPEC®, HIPEX®, and For Tec E® product lines are processed by injection molding or extrusion and provide numerous processing and product design advantages to manufacturers. KRAIBURG TPE features innovative capabilities as well as true global customer orientation, customized product solutions and reliable service. The company is certified to ISO 50001 at its headquarters in Germany and holds ISO 9001 and ISO 14001 certifications at all global sites. In 2018, KRAIBURG TPE, with 640 employees worldwide, generated sales of 189 million euros.

About Gutsche Engineering

Founded in 2013, Gutsche Engineering GmbH, with its registered office near Heilbronn, Germany, has specialized in the development and production of innovative injection molding applications made of technical polymers. The company offers design, tools and products from a single source – from prototype through to production. This provides customer-oriented, flexible solutions with short response times, and it speeds up the implementation of demanding projects. The company’s core competencies include numerous innovative vehicle components made of high-performance plastics, including PEEK and PPS, as well as thermoplastic elastomers (TPEs). In 2016, Gutsche joined the “Entrepreneur for Entrepreneurs“ network. The initiative was founded by Oxfam to overcome poverty by helping people in developing and newly industrializing countries establish their own business. For more information, see

Related images

The roof rail system developed by Gutsche Engineering is part of the standard equipment for German premium SUVs. It rests on bases with two-component covers that take advantage of the outstanding processing properties of THERMOLAST® A as well as of its excellent temperature and weather resistance. 
(Image: © 2019 KRAIBURG TPE)



Editorial enquiries

Simone HammerlSimone Hammerl
Public Relations EMEA & Americas

+49 8638 9810 568

Bridget NgangBridget Ngang
Marketing Manager Asia Pacific
KRAIBURG TPE Technology (M) Sdn. Bhd.

+603 9545 6301

Siria NielsenSiria Nielsen

+31 164 317 036





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