Because of its good temperature resistance, impact resistance and aesthetics appearance, acrylonitrile-butadiene-styrene is often used in household goods and in the automotive industry. The development of a circular economy also shows successes.

More than half of the world’s ABS consumption is accounted for by household and E&E equipment

Acrylonitrile-Butadiene-Styrene (ABS)

Elektronik

Kfz-Elektronik

Kunststoffe

Photonik

Optik

Polystyrol

Kunststoff Werkstoffe

Thermoplaste

Recycling

Umweltmanagement

ABS / ASA-Kunststoffe

Technische Kunststoffe

Kunststoff-Recycling

Kunststoffverarbeitung: Verfahren

Kunststoff-Aufbereitung

Sustainable Growth

Lightweight construction, functionality and design are characteristic of material development in all areas of application for PC compounds, composites and films. The range of materials has enormous opportunities when it comes to the mobility of the future, lightweight structural construction with continuous fiber-reinforced composites, 5G technology and medical technology.

In electric vehicles, the original function of the radiator grille, namely to supply air to the engine, is no longer needed. It can therefore be used entirely as a design element, for example by integrating luminous logos and fade-out effects

Polycarbonate (PC)

Kunststoff

Bauwesen

Baustoffe

Medizintechnik

Polycarbonat

Medizinprodukte

Present in a Multitude of Trends

The transformation from the combustion to the electric engine entails several imponderabilities for the plastics industry. In part, electric drives have completely different material requirements which are becoming specifically evident with the increasing use of appropriate vehicles.

In electric vehicles, the change in engine technology also entails new requirements for the plastic materials used

Flame Retardancy, Heat and Tracking Resistance of Electric Vehicles

Elektromotoren

Antriebe

Elektromobilität

Mobilität

Polyamide

Elektronische Bauelemente

Leistungselektronik

Hochleistungskunststoffe

Drivers of Electromobility

Polymaker will offer the Polymaker PC-r 3D printing filament made from recycled polycarbonate (PC). The PC for the filaments comes from materials supplier Covestro and consists of a combination of recycled plastic waste and virgin material.

The combination of recyclates and virgin material reduces the<sub> </sub>carbon footprint of the polycarbonate and still allows it to be extruded into filaments

Filamente für additive Verfahren

Andere Werkstoffe

Werkstoffe für additive Verfahren

Additive Fertigung

Kunststoff-Rezyklat

Water Bottles Become Filaments

Selected Makrolon RE grades from Covestro are climate-neutral from cradle to gate, thanks to the usage of renewable electricity for Covestro production processes and the introduction of raw materials coming from mass-balanced bio-waste and residues.

For the production of its climate-neutral polycarbonates Covestro uses mass-balanced renewable feedstock and renewable energies.

Erneuerbare Energie

Energieerzeugung

Kreislaufwirtschaft

Covestro Produces Climate-Neutral Polycarbonate

Electrical and electronics manufacturers want to reduce greenhouse gas emissions from their products and optimize waste management and recycling for them. This can be achieved, among other ways, by using more sustainable thermoplastics and quality-assured recyclates. A close cooperation between companies to establish material cycles and the recycling-friendly design of equipment are also important.

16:9

Driving Sustainability Trends in the Electrical and Electronics Industry with Polymers

Support for a Greener E&E World

The combination of injection compression molding, direct coating and partial film insert molding enables a novel design for the front module of the BMW iX electric vehicle. Important in the development were extensive trials carried out by plastics manufacturer Covestro in its technical lab.

Various production processes are combined to manufacture the front module of the BMW iX, known as the kidney.

Producing Large Exterior Parts with Integrated Functions and High-Quality Finishes

Polyurethan

Facelift for Electric Vehicles

A large proportion of the world’s polycarbonate is processed in Asia, especially in China. This is why capacity expansions are mainly taking place there.

PC-based films enable attractive designs in automobile interiors. Electroplated real metal surfaces with touch sensors are a real eye-catcher, no matter whether the backlighting is switched on or off.

Polycarbonate (PC): Functional Integration and New Specialties

Messe K-Kunststoffmesse

kunststoffe-international.com

Kennzahlen

Qualitätsmanagement

Growth Driver China

The Internet of Things offers polycarbonates numerous potential applications. Current examples of IoT devices show the potential that PC offers.

The UV-stable housing protects the inside of the base station against impacts, even at very low temperatures, while at the same time, ensuring stable signal transmission.

Polycarbonates for Smarter and More Sustainable IoT Applications

Smart City

Internet der Dinge

Wirtschaft

Innovationen und neue Technologie

Smart Building

Energieeffizienz

Smart Home

Smart Home / IoT

Maker

From the Internet of Things to the Intelligence of Things

The shift to electromobility is changing the requirements for the used materials. This opens up opportunities for polycarbonate.

Specially adapted polycarbonates lend themselves, for example, as materials for lithium-ion batteries in electric vehicles.

Polycarbonates for  High-Voltage Components

When combining PC with liquid silicone rubber, the heat resistance of the PC is an important factor. Covestro has introduced a special PC for this purpose.

The heat-resistant polycarbonate also boosts productivity in silicone overmolding applications.

Higher Heat Resistance,  Higher Productivity

Injection molding is demonstrating its versatility again in the production of challenging optical plastic parts such as LED lenses for automotive headlights with tolerances in the micron range. A new development in multilayer injection molding allows productivity for the production of thick-walled lenses to be increased even further. 

Spritzgießen

Thick-Walled Lenses: Efficient Production of Thick-Walled Parts 

It is coming this way by giant steps – the K2016. Besides new materials, the materials makers will make it perfectly clear in Düsseldorf, Germany, that they are dealing intensely with global developments and challenges. This also involves taking stock of their global presence. 

How Materials Makers Turn Challenges into Chances 

Additive

Stabilisatoren

Pigmente

Tackling Tomorrow’s Problems Today 

With wide-ranging and specific property modifications, plastics can take more and more applications away from classic metal components. Polyamides and polyphthalamides, in particular, also are extending the performance spectrum, as two new variants show.

Fig. 1. Grivory G5V has significantly better mechanical properties between 60 °C and 100 °C than the familiar Grivory GV

Two New Polyamide Grades Will Make Engineering Components More Cost-Effective

Progressive Metal Replacement

Strategic partnership delivers best practice example of a closed recycling loop for PET-based multilayer.

Best practice example of a closed recycling loop for PET-based multilayer.

Verpackungsmittel aus Kunststoffen

Kunststoffverarbeitung

Verpackungsmaterial

Logistik

Polyethylenterephthalat

Closed Recycling Loop for PET-Based Multilayer

Large-Area Curved Plastic Panels with Integrated Displays

Harmoniously integrating displays into the lines of a vehicle cockpit has always been a real challenge. Continental now uses a combination of film insert molding, in-mold decoration and injection-compression molding to produce large, three-dimensionally formed plastic panels.

The display increasingly sets the tone of a vehicle cockpit. Most current car models already have two full-color, graphic-capable displays. The instrument cluster usually consists of a large display (full digital cluster, FDC). In addition, there is usually a second display in the center console, which presents a wide range of content that is not directly relevant to driving, such as navigation, infotainment and operation. It often has a touch function. For years, the trend has been toward increasing the number of displays, as well as their diagonals and resolution.

Precisely harmonizing the technical properties of such side-by-side displays (white point, color temperature, color coordinates and black homogeneity) represents one major challenge. Another is to integrate the display surfaces harmoniously into the lines of a cockpit. Glass-based displays turn out to be somewhat intractable in this respect. The curvature that can be achieved is in the range from about 800 to 3000 mm radius. Flexible displays such as AMOLED (active matrix OLED) are significantly more promising. However, AMOLED displays must have a protective layer to make them suitable for the comparatively harsh use in vehicles with touch operation.

To solve this challenge, Continental has developed a continuous 3D plastic panel (Title figure). It protects the two 12.3 inch AMOLED displays that it covers against mechanical damage. In addition, the partially printed panel can be merged seamlessly into the surrounding surface, so that the entire curved surface acts like a single continuous instrument. To produce this special interior trim, multiple special production processes were combined with one another for the first time. So-called high-pressure forming (HPF) is used, e. g., for forming the two-dimensionally printed film to the three-dimensional contour of the final part. This is subsequently inserted into a mold and back-molded. This process is called film insert molding (FIM). With in-mold decoration (IMD), the hard coating is applied to the part while it is still in the injection mold in a roll-to-roll process. In combination with injection-compression process, this ensures very low stress conditions in the part. The technical challenge in developing this production process resulted from the dimensions of the panel: the displayed pattern measures around 200 mm x 700 mm. These dimensions cannot be processed by either IMD or FIM processes with >100 mm forming height. At the time of their commissioning, some of the machines used were unique in the world.

The 3D instrument panel is constructed of three functional layers. The reverse side is formed by a printed film (FIM) with 375 µm thickness, the front side is a 15 µm-thick hard layer, which is applied from a transfer film (IMD). The core of the part consists of 2.1 mm-thick polycarbonate (PC), which is injected between the FIM film and the IMD film at the front. It subsequently remains in the mold under homogeneous pressure and temperatures of initially 300 °C during the cooling phase. Despite the size of 200 mm x 700 mm, the roughly 2.5 mm thick end product only weighs 350 g.

This integration would not be possible without extensive technical experience with all the manufacturing technologies used. With the combination of all the steps, together with the three-dimensional contour of the panel, it is actually a completely novel process. Continental benefited here from its many decades of experience in printing and forming films, for example for the dials of traditional tachometers. The automotive supplier’s experience in injection molding optical and highly transparent components, such as mirrors for head-up displays and cover glasses was extremely important. The transfer application of thin films, too, has already been a large-series process for many years, for example for providing transparent indicator points with a luminous surface or producing high-quality piano black surfaces on plastic panels.

Besides the manufacturing technologies, another major challenge was the choice of suitable raw materials. The automotive sector actually makes very severe demands on the materials. They include heat resistance, for example to direct sunlight or the heat emitted from the displays, dimensional stability, scratch resistance despite numerous abrasion strokes and optical quality that must be comparable to high-quality materials such as mineral glass. High impact strength is also necessary in order to prevent splintering of the cover glass, even in the event of head impact in the worst case. In addition, it must also be possible to integrate touch operation. As with every lifetime component in the vehicle, a fatigue strength of over 10 years, or 300,000 km is expected – and has also been exhaustively tested. Only specially selected materials therefore come into consideration.

Figure 1 shows an overview of the two strands of the manufacturing process. The upper strand generates the printed reverse side of the panel by FIM; the lower strand feeds the transfer film with the hard coating. Where the two strands meet, the two film layers are backmolded by injection-compression.

At the beginning of the upper strand there is a large web of PC film (grade: Makrofol HF, supplier: Covestro AG, Leverkusen, Germany). The Makrofol HF is ideal for the purpose due to its high thermal resistance and transparency, as well excellent formability and elasticity over a wide temperature range. This 375 µm-thick film is first printed with functional and decorative motifs, as well as colored features, using a process combining digital and screen printing. Digital printing is used for creating challenging color gradients and graphic patterns. Even photorealistic prints can be implemented by these means.

In an HPF machine, heating tiles heat the finished printed 2D film webs up to its glass transition temperature of 150 °C. Then the heated web is positioned over the 3D mold and the forming mold closes. Air pressure at about 60 bar applies the film to the 3D contour of the mold (Fig. 2).

After removal from the machine, the formed film is cured under UV light. In the prototype production, the 3D blank is then trimmed to the part contour all round with a milling machine, and the required bores are drilled. This process produces the reverse side of the subsequent instrument panel. The HPF machine, from the manufacturer Niebling GmbH, Penzberg, Germany, allows genuine 3D forming of large-size parts with drawing depths of ≤150 mm at web sizes of 1150 mm x 650 mm. The forming tool was specially designed for this process.

On the lower strand of the production line in Figure 1, the transfer is prepared with the hard coating. This IMD film is fed to the injection-molding machine as roll material. With this manufacturing step, too, it was necessary to cross existing technical boundaries due to the three-dimensional and large-size design of the display panel.

Before backmolding, the printed 3D film is inserted into the complex injection mold. The two mold halves together weigh over 16 t. In addition, due to the complexity of the mold, it has a certain built-in intelligence in the form of a programmable logic controller (PLC), which, among other things, supports operation by smartphone via WLAN. The PLC is responsible for monitoring and coordinating the over 60 actuators and sensors that are located in the mold. It independently handles interplay with the injection-molding machine and two other secondary peripheries. During insertion of the FIM, the IMD protection film (type: Bright View; supplier Leonhard Kurz Stiftung GmbH & Co. KG, Fürth, Germany) is positioned in the mold by a special film feeder. To fix the film in the mold, a twelve-part clamping frame concept is used. This fixes the film in the mold using a precisely defined sequence of velocity and position control (Fig. 3). The transfer film is now laid wrinkle-free in the mold under vacuum.

When the two films have been positioned, the mold halves are closed and the films are backmolded with PC (grade: Makrolon Ai, supplier: Covestro) at up to 300 °C. Due to the high temperatures and pressures, the printed FIM and the transparent IMD protective coating become an integral part of the panel. To ensure that the subsequent panel has a uniformly high optical quality, the plastic is injected into the cavity while it is still slightly open, and it is then only closed fully after complete injection. This ensures a low filling pressure and a homogeneous pressure distribution during the cooling phase. Because of the resulting opening forces, the hydraulics of the machine must generate clamping forces of up to 1500 t. As the machine opens, the IMD transfer film is released from the front side of the 3D panel, while the hard layer (protective coating) remains on the PC.

The PC, with its glassy transparency, has high impact strength even at low temperatures and the good dimensional stability gives the 3D instrument panel its strength. After cooling, the IMD protective coating on the final panels is hardened under UV light. The sprues are subsequently removed and the panels are now ready for the optical dry bonding of the two 12.3-inch AMOLED displays.

Plastic panels allow additional 3D structures to be generated on the panel front side, which guide the driver’s fingers during operation of the center console (Fig. 4).

This allows digital operating elements, such as slide controllers for volume control to be replicated. These tactile orientation aids make good hand-eye coordination less critical. The driver can reduce the time he takes his eyes off the road, and maintains a better overview of the traffic situation. In addition, the 3D instrument panel can give the driver tactile feedback. For example, he feels it in his fingertips as soon as he has successfully performed a touch input. The visual check is therefore briefer or entirely unnecessary, which further increases safety. The instrument panel, which is 3D formed for design reasons, thus also supports ergonomic requirements on an operating interface in the vehicle.

The manufacturing processes, comprising FIM-3D forming, roll-to-roll IMD coating and injection-compression, allow large-size instrument panels with high optical quality to be produced. Besides their low weight, they possess many key advantages. First, the combined process allows the integration of curved display surfaces, which principally shifts the center control better into the arc of reach of the driver’s right hand. This makes the functions integrated in the center console display more ergonomic. The possibility of additionally generating three-dimensional structures on the surface of the panel makes operation during driving even safer and more intuitive. And finally, the process permits the seamless integration of individual AMOLED displays without visible transitions between the screen and panel surface. The result is a harmonious cockpit with attractive flowing curves. The innovative manufacturing technology with purpose-adapted machines has proven its effectiveness in the manufacture of prototype panels. The innovative process is therefore suitable for future series deployment.

Continental Automotive Technologies GmbH  

https://www.continental-corporation.com

Ausgabenartikel

Fig. 3. The twelve-part tensioning frame for positioning the IMD film ensures precision fixing of the film before backmolding

Two displays are seamlessly integrated into the continuously 3D-formed instrument panel

Fig. 1. The plastic panel is manufactured in two separate processes, which are then merged together

Fig. 2. The FIM machine for 3D heat forming of large-size polycarbonate arcs operates at 60 bar

Fig. 4. Surface topographies on the panel make blind operation of functions in the display easier

Continental - Hauptartikel

Martin Lenz is Expert Plastic-Design for Manufacturability and technical project manager for the 3D plastic panel at Continental; <a href="mailto:Martin.Lenz@continental.com">Martin.Lenz@continental.com</a>

Kai Hohmann works as a product manager for display products at Continental; <a href="mailto:Kai.Hohmann@continental.com">Kai.Hohmann@continental.com</a>

Read the German version of the  article in our magazine Kunststoffe or at  <a href="http://www.kunststoffe.de">www.kunststoffe.de</a>