ColVisTec AG
Inline Prozess Monitoring

"Color Probe" is designed as an immersion probe, suitable for applications on liquid, paste, powder and pellet type of media. The housing is made of stainless steel (D = 3/4" = 19.05mm) and can be very easily integrated into pipelines, stirred vessels etc. and also used in laboratory applications. The probe tip is also equipped with a self-cleaning sapphire window like the other probes from COLVISTEC.

In combination with the spectrophotometer "InSpectro X" the spectrum of paints, varnishes, printing inks, chemicals, paper, cosmetics, beverages, food etc. is measured.

COST REDUCTION through process monitoring by means of inline UV-VIS spectrophotometry, e.g. in powder coating production or in extrusion.

Continuous spectral measurement directly in the process/material e.g. in the mixer, in the extruder, in pipelines - on liquid, paste, powder or molten media - results in complete documentation of changes in the process/process parameters and immediate intervention in case of deviation from the reference value or permitted tolerances.

EXAMPLE: Powder coating production

There are two critical steps that determine the quality of the end product: mixing and subsequent extrusion. Our inline technology is designed for precisely these two process steps. In the mixing stage, it can immediately detect the mixing quality or faulty mixing, and in the extrusion stage, the dispersion, homogeneity and stability of the process and thus the quality of the end product. Fluctuations in the dosage and quality of the raw materials used as well as changes in the process parameters are always reflected in a color change on the product, this is detected in real time with the COLVISTEC Inline technology. The result is the avoidance of faulty batches and contamination.

Inline process monitoring is also increasingly used e.g. in process development. It stands for the minimization of rejects and avoidance of immense costs, e.g. for working time, delays in delivery dates, raw material usage, recipe optimization and complete quality proof.

Reflection probe RPMP for opaque media and transmission probe TPMP for transparent/clear media are melt measuring probes specially developed for use in extruders, for temperatures up to 400 °C. Both probes can be easily integrated into any extruder. All that is required for the RPMP is a free 1/2"-20UNF threaded hole (typ. Dynisco) and two opposite threaded holes for the TPMP.

RPMP stands for "Reflection Polymer Melt Probe", it is a reflection probe for use on opaque melts. The probe has six illumination fibers arranged in a ring and a central detection fiber for the reflected light from the melt. 

TPMP stands for "Transmission Polymer Melt Probe" and is a transmission probe for use on transparent melts. Two probes are positioned directly opposite each other. One transmits the light, the opposite one detects the incoming light through the melt (transmitted light method).

In both variants, the probe tips are equipped with self-cleaning sapphire windows. Connected via fiber optic cable to the spectrophotometer "InSpectro X", the spectrum of the plastic melt is continuously recorded and displayed as a trend diagram to the reference value, e.g. with the color values (L*, a*, b*, dE*, yellowness etc.). It thus provides complete information on the homogeneity and stability of the plastic melt in the process, without loss of process control. This avoids contamination, false batch or drift. Deviations of this kind can be caused by variations in process parameters (temperature, pressure, speed, etc.) or by the wrong selection of screw components, variations in dosing and quality of raw materials used.

COLVISTEC Inline technology allows continuous monitoring of the production process and immediate intervention to prevent losses in the production and further development of production processes.

Is the API dispersed and homegenically distributed in the polymer matrix?

What is the residence time and what influence does it have on the API?

Is the dosage of the API constant and uniform?

Crystalline or amorphous which is present?

These questions and many more in hot melt extrusion of pharmaceuticals and formulation development can be realized with InSpectro X our UV-Vis inline spectrophotometer in R&D work. It saves enormous time and offers fast data analysis capabilities.

Beside the UV-Vis, we also offer NIR and RAMAN as inline spectrometers for hot melt extrusion with the appropriate fiber optic probes and as „GiANT“ the world’s first „3in1“ spectrometer platform.

The centerpiece of the inline process monitoring is the UV-VIS spectrophotometer "InSpectro X", this covers the wavelength range from 220 to 820 nm and this with a resolution of 1 nm over the entire spectrum. "InSpectro X" is designed with all its components to be robust enough to produce accurate and continuous measurements in the industrial production environment. The stainless steel housing is IP66 rated for protection against splashing water and dust. An integrated, powerful thermo-electric heating and cooling unit ensures constant temperature conditions inside the housing and thus for the optical components. It has two optical interfaces for the connection of two measuring probes for the simultaneous monitoring of two processes with one system. All COLVISTEC optical fiber probes (CP, RPMP, TPMP and others) can be connected to the "InSpectro X". The complete system is completed with a comprehensive software designed for process monitoring. This is easy to operate and easy to integrate into the process control, e.g. via software interface (OPC UA) or analog as current/voltage signals. Other software packages such as the residence time analysis (ReTA) software are also available. With ReTA it is easy to perform residence time measurements elegantly and to analyze them directly after the measurement. All this without taking samples and the associated time-consuming analytical work in the laboratory. All residence time relevant data (numerical as well as graphical) are available with one mouse click directly after the measurement, e.g. mean residence time, Bodenstein number, distribution of tracer amount over time, etc.