Extrusion International 1-2026

22 Extrusion International 1/2026 INDUSTRY NEWS Quality Assurance in the Colouring of Recycled Plastics Recyclates pose an enormous challenge when it comes to colouring plastic products. The SKZ Plastics Centre has responded to the demands of the industry by creating a course that teaches the basics and provides solutions.

 Colouring plastics is considered challenging even with new materials – process parameters, materials and co- lourants must interact perfectly. However, in order to achieve precise colouring, e.g. due to OEM specifications or for corporate identity reasons, it is extremely important to be able to match colours accurately and consistently. With increasing requirements regarding the circular economy, the use of recycled plastics is also becoming increasingly important. This means that the challenge is growing: despite fluctuating material quality, foreign polymers and colour deviations in the input material, the visual and functional quality of the products must not suf- fer.

 To support companies in this demanding task, the SKZ Plastics Centre offers the continuing education course Quality Assurance in the Colouring of Recycled Plastics. Participants gain practical insights into current processes, tools and control techniques that enable stable colour quality even with fluctuating material properties of the recyclates.

The course content includes:
 • Current challenges in material and colour sorting
 • The problem of black plastics and new approaches to solving it
 • Colourants for the circular economy (e.g. alternatives to carbon black, masterbatch based on recycled materials)
 • Modern measurement and control technology for pro- cess-oriented colour control and foreign material detection
 • Ecological aspects of recyclate use

 Practical demonstrations and video examples make the content tangible: participants experience measurement systems for colour prediction, material determination and automatic colour adjustment live in action, enabling them to efficiently transfer what they have learned into indus - trial practice.

 „A fully circular economy can only succeed if the quality characteristics of plastic moulded parts are not compro- mised. This requires competent specialists who are able to accurately assess the technical possibilities and limitations. Our course offers concrete methods for this and presents practical solutions,“ emphasises Christoph Kreutz, expert trainer at the SKZ Quality Management Training Centre.

 SKZ Plastics Centre Christoph Kreutz 
c.kreutz@skz.de Extruder with different colour strands (fictitious) (Photo: SKZ) New 500 Series Rubber/ Silicone Extrusion Crosshead Guill Tool introduces the NEW 500 Series crosshead with MAGS gum space adjustment. The 500 Series is designed specifically for the flow characteristics and unique pro - cessing challenges of elastomeric compounds. One of the key features engineered by Guill on this new crosshead design is the mechanically assisted gum space (MAGS) ad - justment system. This new method of gum space adjust- ment allows the operator to make an effortless adjust- ment from a single point using a common socket wrench. No more need to struggle with multiple nuts and bolts in order to adjust gum space, which leads to faster adjust- ments. The visual indicator on the core tube allows the operator to see how far the gum space has been moved, making those adjustments much more accurate and re- peatable. The hardware-free and patented cam lock design of the new 500 Series from Guill means no time is wasted unbolt- ing and re-securing fasteners for disassembly and re-as- sembly. Only half of a rotation of the cam nut is required to loosen and automatically extract the deflector from the head body, which is another time saver. Also, with no un- Guill Series 500 crosshead with Mechanically Assisted Gum Space (MAGS) adjustment, specially designed for the flow characteristics of elastomeric compounds