SPECIAL PRINT. Issue 10/2016. Kunststoff-Profi Verlag GmbH & Co. KG Saalburgstr. 157, D Bad Homburg Phone: ,

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1 Kunststoff-Profi Verlag GmbH & Co. KG Saalburgstr. 157, D Bad Homburg Phone: , Wenn Flow-coating man immer involves das macht, a great was deal man of detailed immer knowledge : macht, entwickelt How Weidplas sich nichts developed weiter the Wie world's Kühnlein first die series Herausforderungen application injection vom Prototyp mold bis coating zur Großserie technology, meistert Colorform Kunststoff-Profi Verlag, Bad Homburg. All rights, also regarding the reprinting of extracts, the photomechanical and other reproduction, distribution and translation are reserved by the publisher. SPECIAL PRINT

2 2 TECHNOLOGY Flow-coating involves a great deal of detailed knowledge How Weidplas developed the world's first series application for injection mold coating technology, Colorform Photo: KraussMaffei

3 TECHNOLOGY 3 The high-gloss finish is created right in the injection mold by flow-coating with a twocomponent polyurea paint system in Piano Black adapted here to the PSA Black specification for the customer Peugeot. Steffen Reuter: Colorform technology has so much potential. As a system integrator, we have broad knowledge and many more ideas. Is Colorform already in series production? Recent events now mean the answer to this question is yes. In early October, the first serial components ever decorated using Colorform technology stunned onlookers at the Paris motor show on the newly-introduced Peugeot A-pillar paneling for the SUV leaves the injection molding cell at the Rüti plant of Weidplas GmbH, Switzerland, ready-to-install and painted in highgloss black. And another OEM has already placed the second series order. Six years ago, KraussMaffei introduced the one-shot process for producing high-gloss paint surfaces directly in the injection mold for the first time at K On its visit to Switzerland, K-PROFI learned what hurdles Weidplas had to overcome as system integrator on the way to series production with partner companies KraussMaffei and Panadur, what untapped potential Colorform technology still has and how Weidplas generated real added value with Colorform. Text: Graduate Engineer (University of Applied Sciences) Sabine Rahner, editorial staff K-PROFI Twelve years earlier at K 2004, KraussMaffei had already combined process injection molding and polyurethane reaction process machinery. The introduction of Skinform technology at that time for components with a leather-like feel laid the groundwork for additional process combinations. Two similar innovations followed at K 2010: One was Coverform, a one-step process to replace conventional transparent scratch-resistant coating of PM- MA components (a joint venture with Evonik). The other was Colorform technology, which allows the part to be flow-coated with a polyurea reaction coating from Panadur while still in the mold, regardless of the substrate, and consequently painted in the desired color, for example Piano Black or Clear, without significantly lengthening the injection molding cycle. K 2010 also provided the pivotal platform for Weidplas GmbH, which is now a member of the Techniplas group based in North America. Steffen Reuter, Vice President of Innovation & Technology, Daniel Schelter, Product Manager for decorative parts, as well as Marcel Stössel, responsible for operating materials procurement as Head of Industrial Engineering, visited six months prior to the trade show to find out more about the wide array of decorative technologies.

4 4 TECHNOLOGY K-PROFI: What were your intentions in coming to Düsseldorf? Steffen Reuter: Back injection of metal foils is one of our core technologies. We were considering what we want to offer beyond that in other decorative solutions. When talk turned to interior vehicle components, coating quickly came up. At the same time, it was clear to us that conventional wet coating is not the technology of the future and that we at Weidplas were not going to invest in a painting facility. Therefore, we concerned ourselves with new, innovative technologies for paint surfaces and screened the market. How did you go about this? Steffen Reuter: K 2010 showcased many different systems. We gave in-depth consideration to Coverform and Colorform from KraussMaffei as well as a few competitors' products that to some extent prioritize transparent coatings, and began an evaluation process. Our approach focused on high-gloss black. As a result, we decided on Colorform. What was the deciding factor? Steffen Reuter: Sustainability was a key issue for us. Sustainability of components and of the entire process. An important advantage is Panadur's lack of solvents and release agents since the application of a release agent does not go with a clean injection molding process. Marcel Stössel: The second reason was that we did not want wet coating under any circumstances. This injection molding/reaction process machinery combination was the only way for us to break into the market for decorative components in addition to PMMA high-gloss surfaces, which we also offer. Steffen Reuter: And there's still a third reason. Automation plays a big role in securing jobs work in Switzerland or Western Europe generally. We need technologies that allow for automation and integration in the manufacturing process. What was the first step after deciding on Colorform? Steffen Reuter: Along with KraussMaffei, we decided which application we wanted to use to test the technology. As a result, we selected an interior part, a trim strip, which we wanted to use to show what more we could do compared to coating. Just flowcoating a simple component would not have showcased the true potential of this technology on the competitive coating market. We instead processed various colors and materials in the trim strip mold, as well as different surface structures like high-gloss matte or grained, and investigated the possibilities that this technology might actually hold. Daniel Schelter: The paint's ability to work so well comes from the intensive development process and indepth discussion with Panadur over the last few years. Steffen Reuter: Colorform technology has so much potential. As a system integrator, we have broad knowledge and many more ideas. Marcel Stössel: Wet coating was out of the question. Colorform was the only solution for us to get into the market for decorative components.

5 TECHNOLOGY 5 What was the result? Daniel Schelter: This technology allows us to generate variants very quickly. We played around with the cavities on this first demo component: a grained surface for the base cavity, high-gloss surface for the flow-coating cavity. Flow-coating just one surface in one shot and both in the next. Colorform provides completely new design options. Steffen Reuter: The trim strip application taught us a lot in terms of paint, paint adhesion and paint modification. That was the first step, so to speak. Even if I want to replace existing technology with new technology, the central question is: How much added value can we create? Such as through multi-colored finishes, different surface structures, transparent painted surfaces with depth effects, partial graining, design lines, logotypes and much more. We then built a demonstration at the K 2013 trade show with KraussMaffei and mold manufacturer Hofmann to actually showcase these advantages and address the needs of designers in the automotive industry. What do the designers want? Steffen Reuter: Radii approaching zero and sharp, precise lines and exciting, arched surfaces. But the wet coating process only met these needs in part. We demonstrated these aspects at the trade show. In terms of functional integration, we also incorporated an optical fiber and used it to create uniform lighting over large surfaces. And, lastly, we demonstrated at the K 2013 trade show how Colorform makes it possible to achieve a high level of automation and production integration. What happened after the K 2013 trade show? Steffen Reuter: We also saw great potential for using this technology in exterior applications. So after successfully completing the first two projects, we busied ourselves with exterior components and implemented Colorform in B-pillar paneling. The mold was constructed with our in-house moldmaker at the time. We also invested for the first time in our own PU system for our Tech- Center. We definitely learned a lot from the trials and tests in the KraussMaffei Tech- Center. Even when you want to bring such technology into production, you need to be able to develop it further in-house. Which challenges did you still need to overcome before the project was finally brought to series application? Steffen Reuter: The real challenge was showing customers that Colorform is the right technology. It was very helpful that we had already gathered experiences from three projects and, for example, could conduct various tests to customer specifications. During this period, we held numerous conversations with designers and automotive materials specialists. Many had already worked with this technology. We sensed that there was interest from the market, but to date no one had had the courage to take the first step. With new technologies, OEMs always ask, Is the technology already in series productions? That's why we are particularly proud that we got PSA on board with Colorform two years ago. What tipped the balance for your first Colorform customers? Steffen Reuter: For PSA, it was the premium quality you can attain with Colorform. Is Colorform more cost-effective when compared to conventional coatings? Steffen Reuter: Definitive cost information is rather difficult because the layer of paint Weidplas started producing the A-pillar panels for the new Peugeot 3008 using the Colorform system at its plant in Rüti this last summer and is the sole supplier of the component. Vinod Ponnambalam handled the integration of injection molding machines, reaction process machinery and automation in his role as control engineer at KraussMaffei Automation GmbH. used with Colorform is thicker than with traditional coating, meaning more material generally gets used. But the overspray portion of traditional coating is often not given consideration. But cost is not the deciding criterion. Much more important is the added value of Colorform, the design freedom and new possibilities compared to a standard coating process, such as further functional integration or multi-colored coating, that then have additional cost-saving potential. Now customers need to learn how to Photo: KraussMaffei

6 6 TECHNOLOGY work with this technology, to uncover the added value and consider what it's really worth. Wet coating is naturally more cost effective when it comes to a simple rectangular plate for example. But as soon as we need to consider multiple colors, partially matte surfaces or incorporating logos and I have to stop a conventional coating process to do masking and I have to coat the product several times, the advantages of the Colorform system can be truly appreciated. The requirements in the automotive industry are obviously very high. Were you able to conduct all of the tests successfully? Daniel Schelter: We continuously tested weathering and color fastness as well as scratch resistance during the development project. These results were the basis for receiving the series order in the first place. Before the actual commissioning, we then carried out more, PSA-specific tests. The paint's ability to work so well comes from the intensive development process over the last few years. We communicated the requirements and wishes of the end customer with the paint manufacturer Panadur, who continuously refined their paint. To what extent did the paint need to be adapted to the current series application? Daniel Schelter: We needed to adapt the reaction time specifically for our series component so that the coating process matched the injection molding cycle. Tuning the material properties to the specific customer requirements was a challenge in developing the paint. Optimizing the interactions of different, often contradictory, requirements was especially difficult, such as providing a paint with both scratch and UV resistance. Steffen Reuter: This was ultimately the focal point of the second part of Colorform development. What are the boundaries to how I can adapt the paint? What specifications apply to different OEMs? How can we achieve color matching? Etc. Daniel Schelter: For example, PSA as is also the case with other OEMs has its own unique black that differs from standard black. It requires other color and carbon pigments. At the same time, it is important to ensure that the ability to flow, the reaction speed and all other properties are retained. Panadur developed the paint here according to our specifications and wishes. We actively communicate and Panadur implements new paint preferences or formulations very quickly. Steffen Reuter: A note about scratch resistance: We conducted a number of trials in which we intentionally scratched components in order to subsequently polish them to perfection. Compared to conventional paint application, the thicker layer allows you to repeat this process several times. Did systems engineering also need to be optimized? Steffen Reuter: Wear from nanoparticles in the paint finishing system is a significant challenge. KraussMaffei responded to this with higher quality materials in the system components. We now use other pump systems in the reaction process machinery than those used in the system displayed at The choice of a swivel plate design allows operation with a markedly smaller injection molding machine (6,500 kn in this case) compared to a design with a rotary table mold.

7 TECHNOLOGY 7 Daniel Schelter (right) and Marcel Stössel point out the extreme, geometric dimensions produced by flow-coating. With a wall thickness of 0.5 mm and a width of 35 mm, the entire component length of more than 1,000 mm is flow-coated. the K 2013 trade show. All of that is the result of experience we had in the last year as a system integrator. What role did Weidplas take in the developing Colorform? Steffen Reuter: Our responsibility is that of system integrator. The many interfaces each require a lot of expertise: product design and component design, materials and paint, system and mold technology. Everything works together here in our setup and we get the big picture. We focus the process and coordinate the necessary adjustments and optimizations with regard to the component, the system, the mold and the paint. Our task is and was getting everything working together so that there is ultimately a stable series process. This integration expertise, and having spent so much time grappling with Colorform during our innovation and predevelopment process, secured a clean series launch for us. This let us mitigate a portion of the risk in advance. You started producing the first ever Colorform series part this last summer. What challenges face did you have with the component? Steffen Reuter: For the P8 platform from PSA, we are the sole supplier of A-pillar paneling which seals off the pillar from the windshield outside the glass. At the same time, the high-gloss black paneling functions as a dramatic styling element for the premium-quality vehicle series. The geometry of the component is extremely long and narrow, extending over a meter and just 35 mm wide. We had never created such a long component in Colorform before. We start by flow-coating the part on one side and continuing over the entire component length with a layer of paint of up to 0.5 mm. We needed to learn a lot here: from the design of the mold to adjusting the process parameters, finding the proper processing window, modifying the paint in order to control flow-coating to adjusting process parameters to change the paint quality in turn. We built up this knowledge as a system integrator. Flow-coating involves a great deal of detailed knowledge. The design of the Colorform production cell installed by Weidplas at their Rüti plant is based on experience from the trade show project for K It is also how Weidplas decided on swivel plate technology, in which a GXW 650/1400/2000 Spinform injection molding machine has been implemented with 6,500 kn of clamping force. The second injection unit is used to apply a TPE sealing element. This produces one set per cycle with a left and right A pillar paneling. The Hofmann Innovation Group from Lichtenfels, Germany built the 4.5-ton swivel plate mold with four cavities, a multi-sprue system as well as hot runner technology from HRSflow. The automation and reaction process machinery for the Panadur Black polyurea lacquer are also from KraussMaffei. A two-component metering machine of the Hybrid Flex 0.2-4/4 variety with a servoelectric metering piston is used for the abrasive A component. A two-component MK5/8ULPK-2KVV mixing head is also used, which is flange-mounted on the injection mold. KraussMaffei serves as the system provider of the fully automated cell where an IR 1500 six-axis robot from Kuka takes over the handling of the components. What does the process workflow look like in detail? Steffen Reuter: We don't want to give away all of the details, since that covers the expertise that we have worked so hard to obtain. We produce the two-component part made of a thermoplastic material and TPE and we flow-coat two cavities with the polyurea coating in high-gloss black for a set of left and right panels. The six-axis robot unloads the components from the mold and places them in the rotary index table, where the panels are processed to completion entirely automatically.

8 8 TECHNOLOGY Daniel Schelter: If the customer suddenly needed white-coated components, that would be an issue since the switch from black to white is nearly impossible. But otherwise there's a measure of flexibility. How quickly can a color change be carried out? Steffen Reuter: So far, the color component is included right in the A-component of the two-component paint finishing system and is in the entire tank and in the hoses, which means a color change would be difficult. KraussMaffei is presenting a three-component mixing head at K 2016 where the color is added to a transparent system, which is the necessary and logical step for the future of Colorform. A color change is then possible in just a few minutes. Moreover, it saves resources. This three-component mixing head is one of the responses stemming from our joint development. What limits do you see with Colorform? The reaction process technology for the polyurea coating includes a two-component metering machine with servoelectric metering piston for the abrasive A-component How high is the reject rate? Steffen Reuter: The parts come out of the system with a very high level of quality because the surface quality is defined by the mold cavity. This is why the reject rate is lower than with painting. That's also an important aspect in relation to the sustainability of this process. Could you say that Colorform saves space? Marcel Stössel: Thanks to the SpinForm technology, the machine is noticeably smaller than if we were working with rotary table molds for example. With KraussMaffei as a turnkey supplier, we have put immense effort into achieving the very best in terms of automation in the system layout. And if we compare it to conventional painting technology, which includes transport and storage, Colorform provides advantages for total space requirements either way. Colorform lets us produce panels that are ready to go in the containers that can go right to Shipping and onto the truck. This effectively allows us to produce in step with the customer, truly just-in-time and without the need for any storage area. Daniel Schelter: The technology itself as well as the chosen mold design makes the manufacturing concept relatively compact. You are the sole supplier for the A pillar paneling and use just-in-time manufacturing. Is there a backup solution? Steffen Reuter: In a worst-case scenario, the Colorform system in our TechCenter is still available to us. We could convert it in a relatively short time. I'm sure that the demand for Colorform will grow and once we have two or three systems in production, this won't be a concern at all because we'll have greater flexibility. Photo: KraussMaffei Steffen Reuter: We have a lot of freedom in design, but there is certain limitation because we must seal the cavity for flow-coating and this seal geometry has to go somewhere. The sealing edge and the vent design are limitations. Marcel Stössel: The component design needs to go along with the mold concept. You must start by considering the mold concept to be used to implement the component. We also always have a sprue and overflow cavity. This must either be concealed through the component design or in conjunction with add-on pieces. Daniel Schelter: We must be mindful of the form in which the Colorform component is brought together with the add-on pieces and how we can arrange them. Dimensional accuracy is the key idea. What experience have you gained in this area? Steffen Reuter: The coating thickness is configured with significantly more precision in the Colorform process compared to in the wet coating process, since the layer thickness in wet coating is always set by the spray. The mold-based paint application in the Colorform process results in a greater accuracy from a process technology standpoint. You got PSA on board with Colorform. Are other OEMs interested in the technology? Steffen Reuter: We already have a second series order from another customer. We are in the process of making the mold. SOP is early next year. Due to the customer's unit quantity, the mold can run on the same system. Colorform is now in series production. How is further development of the technology going in-house? Steffen Reuter: We still have many ideas that we want to implement. After the series launch was successful, we could start looking at new ideas again. To that end, the Colorform in our TechCenter plays an important role. For example, metallic coating with Colorform is a very exciting topic. The basic studies carried out to date on this topic look very promising.

9 TECHNOLOGY 9 Where is there still potential in Colorform? Steffen Reuter: Colorform still has an enormous amount of potential. From the aforementioned paint finishing system with metallic effects to broad functional integration possibilities and finally to the size of the components. A bumper made with Colorform technology? It may be feasible, just not in our case. We spend 80 percent of our time traveling around the world with our machines in a clamping force range of 6,500 to 8,500 kn. We will continue to work on the technology and the components will not become simpler. We want to expand the competitive edge that we have worked hard for in system integration in recent years. You need to have a very good understanding of the system in order to know what is doable and where the limits are, especially in functional integration. That's the beauty in the role of the system integrator: we possess extensive knowledge. We have come so far today as a result of the in-depth cooperation between the teams at KraussMaffei, Panadur, Hofmann and, of course, Weidplas. KraussMaffei served as the system supplier of the three critical technologies of injection molding, reaction process machinery and automation in the process and provided us with lasting support. Who else is employing Colorform technology? Colorform at K 2016 KraussMaffei Colorform systems have been configured individually and specific to the project to date. A GXW ColorForm is a new, compact machine being presented at the K 2016 trade show. It brings together all of the components for processing of a painting system (polyurea or polyurethane) into a single production unit (photo). The new standardized configuration enables faster project launches and reduces engineering effort. Especially for new users, this is expected to make the introduction into the one-shot process easier. Compared to previous systems, the manufacturing cell is about 20% more compact. Significant changes can be seen on the mixing head for the paint finishing system, which is lighter and approximately 30% smaller. This makes installation on the mold and every aspect of handling easier. Designed as a three-component mixing head, it makes it possible to change colors on a scale of just minutes. Whereas the pigment has previously been integrated into the A component of the paint finishing system, the new mixing head meters the dye directly during injection. KraussMaffei at K 2016: Hall 15, Booth B27/C24/C27/D24 Steffen Reuter: To my knowledge, only a few research and development institutions, like the Kunstoff-Zentrum Leipzig plastics research center or the KraussMaffei TechCenter in Munich, are using Colorform systems. The first series application is now underway at Weidplas. We had the courage to begin implementing ColorForm technology because we were confident about it and we still are. I am positive that we are going to open up the field for the compact class as well thanks to the premium appearance that can be achieved through ColorForm. ColorForm will be a success Photo: KraussMaffei The world's first Colorform series application in the new SUV Peugeot 3008: The A-pillar paneling and the Black Diamond roof together provide some of the most important style elements of the vehicle design. Photo: Peugeot