Laser welding, laser scribing and laser cutting are essential techniques that REHAU employs when processing polymers.
Laser welding entails joining two elements without affecting their geometry and dimensions. The upper element is transparent to the laser wavelength used whilst the lower element absorbs the waves. The resulting heat and the pressing together of both elements melts the materials at the point of contact and a weld seam is created. Laser welding makes it possible to join different polymers without undergoing a lengthy process. It is even possible to achieve invisible welding seams on colored plastics as the zone subjected to heat is limited. REHAU mainly uses the contour welding and simultaneous welding processes, but the particular process is developed to suit each particular type of polymer.
To apply product inscriptions, REHAU uses the laser scribing process that is extremely precise even with inscriptions that are measured in just a few millimeters. Various effects and contrasts can be achieved depending on the characteristics of the particular polymer concerned. The color of the polymer can be changed, for instance, by foaming or carbonizing. Laser engraving does not necessarily produce visible color change but the engraving is evident as a contrast to differently structured surfaces. Laser scribing is a very precise process and the inscriptions it produces are hardwearing and rich in contrast. The inscription is therefore an element of the product and it identifies pipes and extruded profiles.
Laser cutting is carried out without contact and makes precise cutting quality possible. Other tools, such as punching heads and matrices, are no longer required. Laser cutting is the only commercially viable cutting method for particular materials and composite materials, particularly when the quantities involved are small. REHAU uses the laser fusion cutting process when fabricating bumpers and the laser sublimation cutting process for obtaining high-quality cut edges.
Laser technology in furniture design
Edgeband laser welding in the furniture industry is a special process that uses lasers . Up to now, furniture boards and edgebands were bonded together using adhesives. An unsightly adhesive joint is always the result. Using the new laser welding process, REHAU bonds board and edgeband entirely without adhesive. For laser welding, the polymer edgeband consists of two layers. The layer on the back consists of a special polymer that matches the basic color of the edgeband. An extremely efficient laser melts this layer to make it bond with the board and achieve a lasting, seamless joint. With this new process, REHAU is setting new standards in quality and furniture design at a single stroke.