20 years of experience with PU tools

For more than 20 years, Siegfried Hofmann GmbH has been impressing its customers with technological progress in the design and manufacture of PU tools. Customers benefit from a special PU seal design, economical technology combinations and, soon, an efficient patented solution for ultra-thin PU coatings.

The polyurethane experience of Siegfried Hofmann GmbH has been around for so long that it should have had its driver’s license long ago. As early as 2004, Hofmann developed its first in-mold painting test tool with PU: the then-revolutionary technology made it possible to produce injection molded parts with high-gloss surfaces in a one-step process.

As part of a trade show project, the first large PU coating mold with a durable PU coating was created: The 4k mold was presented at the 2010 K show with two different polyurethanes, two mixing heads, ABS and PMMA. The solution for scratch-resistant, high-gloss surfaces replaces the traditional painting process and is particularly popular in the automotive industry because the risk of rejects is significantly lower than with the traditional painting process. Numerous tools for large instrument panels, trim, armrests and door panels followed starting 2011. The series debut of a Hofmann PU injection mold started in 2016 for the production of scratch-resistant, high-gloss A-pillars with a cycle time of 60 seconds for a French car manufacturer.

Hofmann PU serial injection mold, producing A-pillars

More than 80 realized tools – burr-free but efficient

Thanks to its long history with more than 80 realized polyurethane tools, Hofmann offers its customers comprehensive expertise. Traditionally, Hofmann’s PU tools benefit from an exclusive sealing design that prevents the highly liquid PU from overflowing during the injection process. This design solution prevents the formation of unsightly burrs and ensures particularly high-quality surfaces.

In particular, new technology combinations such as polyurethane, injection compression molding and smart films in a single mold offer huge advantages in terms of cycle time, product design and process efficiency. These synergy effects can currently be seen in the form of Ambient Lightning interior trim, front ends, diffusers or exterior trim on many German premium cars.

PU research work continues

Hofmann is not satisfied with this: The family-owned company is currently working on a patented technology for extremely thin PU layers. In addition to material savings, the aim is to achieve positive ecological effects in terms of weight, CO2 footprint and energy consumption, as the classic PU thicknesses of around 0.5 to 0.8 millimeters are to be significantly undercut.

Interested parties can register for the introduction of the PU solution at Hofmann by sending an e-mail to sales@hofmann-impulsgeber.de.