Color Measurement in Coating Industry, Plastic Industry, Textile and Food Instustry

In the painting and coating industry as well as in the textile and plastic industries colorimeters have been in use for many years. The processing industries are discovering the advantage of colorimeters more and more. Colorimeters have a favorable effect on production monitoring and quality control.

Judging colors is a very subjective matter. Moreover one cannot sense colors with the same sensitivity everyday. Sometimes they are more or sometimes less differentiated. The usage of colorimeter allows an objective control of colors. This is especially required when different suppliers have to provide components of the same color. Colorimeters are available for various purposes and requirements in different categories and different price ranges.

Individual coordinated colorimeters are offered for different, industrial requirements.
The following colorimeters permit - unless differently specified - both an absolute difference and a measuring difference for various colorimetric systems:

  • CIE xyY
  • Hunter
  • CMC

In addition, white and yellow degrees according to ASTM E313-98 and the metamerism index according to DIN 6172 can be determined. 

All described colorimeter can be connected to a computer with the operating system of Windows and they can also be controlled by it. Either it is connected through the serial interface or via a USB port. You cannot only store color standards, but also the color standard’s individual pass/fail tolerances. This is a very important criterion because there are no universal color tolerances.

The relative acceptable tolerance size depends on several factors. Several factors are, for example, color, materials or surface texture, but also the application area of the colored product or the customer requirements. Everyone who is using color measuring technologies in quality control, is recommended, to determine pass/fail patterns after visual aspects considering its own individual requirements. Then the samples should be measured. Resulting color distances to the origin pattern form the tolerances that are deposited in the  colorimeter.

Colorimetry allows a consistent quality by objective examination, also of different people. The main difference between the different devices is the measuring geometries. On the one hand there are  devices that illuminate the sample with diffuse light and measure the reflected light at an angle of 8° and on the other hand, those which bring an adjusted ray under 0 ° (vertical) to the sample and measure the light  eflected under 45 °.

The d/8 measuring geometry (diffused light) is popular primarily in the painting and coating industry. This measuring method is particularly an advantage when comparing patterns with differentiated surface conditions (such as gloss) regarding to the hue but the surface effects disarrange the results of the color measurement.
The 0°/45° measuring geometry is particularly suitable for high-gloss surfaces, for matte textile patterns and when it comes to the point, to achieve visual optimal matching.