Measuring recycled plastic: Accurately automated control due to LAB color measurement system

For the plastic recycling industry applies: the better sorted on detail level, the higher the decrease of the end product. Checking the quality and color is essential in the business. To guarantee the quality a LAB color measurement system can offer the solution.

What is a LAB color measurement system?

For the quality of an end product you are dependent on the quality of the recycled plastic. Here the color difference is often large. The question is what needs to be mixed with each other to end up with the correct result. The LAB color measurement system monitors and recognizes deviations in color and clarity.

How does the LAB color measurement system?

The LAB color measurement system determines the exact color of different recycled plastic material, so that the correct mix can then be made for a particular RAL-color

Components of the color measurement system

  • The laboratory measuring instrument in a stainless steel housing with a PC-panel, keyboard, mouse and 24V supply.
  • An external label printer
  • Supplied accessories
    • 12 sample containers
    • 3 RAL calibration cards (extra options are possible)
    • Pre-installed software package for measurement, logging and calibration of the measurement instrument.

The method

The measurement starts to pour the chosen pellets (recycled plastic that is added together and is usually stored in a silo) in a funnel. The integrated sensor measures the color, behind a glass plate, within a second. The sensor has a large diameter (20 mm) so that the differene in the position of the pellets with multiple samples has minimal infuence on the measuring result. After the measurement, the content in the funnel ends up in the sample container via a slider.


The correct observation

People can see colors with a wave length between the 750 and 400 nanometer. To simulate this observation the LAB colour measurement system uses the 0°/45° method.

Improved calibration

The LAB color measurement system is capable to measure similar values for products with different shapes and dimensions. This way the minimal color differences are detected and monitored immediately.

Immediate insight

The outcome of every measurement is immediately retrievable in the connected software. This can be seen via the connected screen and can be printed out with a simple push on the button. In the results are for example described what the L*a*b* color values are and which deviations these has in the delta (dL*da*db*). The dE-values are shown numerically. The dL*da*db*- values are displayed graphically on the screen as a trenddisplay of the last 100 registered values.

The system saves the measured values. It is possible to complete the information with extra insight in for example recyclate designation and date and time of the taken granulate sample.

With a LAB color measurement system you are assured of:

Quality - The system measures and sorts plastic products in different shapes and dimensions extremely accurate.

Continuity - By measuring at different wave lengths the results of the LAB color measurement system are very correct and constant.

Productivity - The outcomes of the measurements are clear, concrete and are printed out with one push on the button.

Stricter requirements in the plastic recycling industry for producer and end customer

The requirements in the plastic industry are becoming increasingly strict. In the near future a plastic end product needs to consist for a minimum of 55% out of recycled plastic.

Furthermore the demands for the quality will be stricter. End customers are soon mandatory to offer food and beverages in plastic that for 95% consists of recycled material which is never used for non-food articles.

These stricter requirements make it trickier to deliver the desired products. The more recycled plastic, the harder it is to offer the correct color. This results in the increasing importance of accurate color measurement for the future.

Contact product specialist

Our employees are ready to provide you with the best advice. Fill in the contact form and describe your desired application with as much detail as possible! Our experts get to work immediately.