Color measurement of solid colors in the laboratory: spectro2guide and color2view with smart-lab Color

1. Management of color specifications

For efficient quality control, an easy to recognize Pass/Fail indication is a major benefit. Therefore, smart-lab offers a comprehensive standard management to define color & gloss tolerances.

1.1    Setup of master standards with tolerances

Color & gloss specifications can be defined by setting up product families with Pass/Fail limits. If needed “yellow” warning ranges can be input giving the user enough reaction time before the product is out of specification. Weighted color difference equations (e.g. ?ECMC, ?E*94, ?E00) are included to ensure excellent agreement with visual perception.

1.2    Exchange of digital standards for a seamless workflow

Thanks to the outstanding inter-instrument agreement of spectro2guide and color2view “digital standards” can be distributed on a global basis – even between portable and benchtop instruments! Color standards can be exported in xml file format and send by email to the entire supply chain, making sure that everybody is using the same target and tolerances.

Abbildung 1 Definition of digital master with tolerances and limits

2. Project management of test series

smart-lab uses projects to organize measurement data. In R&D studies are performed to evaluate the influence of material properties, raw material concentration levels and changes of process parameters that can affect color and gloss data. Weathering studies for new colors and materials investigate how color and gloss might vary. For paint batch QC the different corrections steps need to be recorded until color and gloss specs are met.

2.1    Online measurement in the lab

Just connect the spectro2guide/color2view with the PC, measure the master panel, apply the respective tolerances and compare the actual samples against the standard. Alternatively, you can recall a standard and samples from a database and quickly add new readings. The data are instantly displayed in a data table with Pass/Fail information and shown in various color graphs.

2.2    Transfer saved data for detailed analysis  

Or do you want to take the spectro2guide with you to the production line? No problem either! The spectro2guide stores up-to 4.0000 standards and 10.000 samples and offers onboard analysis tools like statistic and difference mode. For further evaluation and documentation, the stored readings can be transferred to smart-lab Color.

Abbildung 2 List with recently used projects

3. Analysis of color and gloss data

smart-lab Color offers a variety of professional QC reports to make data analysis easy and comprehensible: data table, CIELAB scatter plot, trend line and spectral curve.

3.1    CIELAB plot with data table and traffic light function

Color difference data are charted in a common CIELAB scatter plot. Tolerances are shown as red and green lines indicating the FAIL and WARNING level. An easy-to-read data table displays the numerical values of the test series. If individual color components are out of specification, the data is colored to indicate the direction of the deviation. Additionally, the Pass/Fail result is symbolized by a green – yellow – red traffic light.

3.2    Color data under different illuminants

Color consistency under different light sources is important especially for multi-component products. Thus, smart-lab allows to display individual CIELAB scatter plots for up-to 3 illuminants. Additionally, samples can be organized in different groups e.g. all samples that are visually Pass can be grouped together. For ease of visualization each group is displayed in the same color in the graphs.

Abbildung 3 CIELAB plot for three illuminants with Pass/Fail indication

4. Special indices analysis

Besides conventional color and gloss control, there are also special applications that need to be mastered in a laboratory. 

4.1    Evaluation of fluorescent materials

Quality control of fluorescent materials is a major challenge. spectro2guide and color2view offer for the first time a built-in fluorimeter, which supports in this task. The new dE Fl index, shown in the data table, provides a prediction of how much a fluorescent sample is likely to change due to exposure to sunlight. The “fluorescent slider” allows analyzing the fluorescent data in detail.

4.2    Evaluation of Deepest Black (Jetness)

Measuring deep black colors puts the quality of a spectrophotometer to the ultimate test. smart-lab Color with the Pro-family analyzes the lightness and undertone of blacks with special indices (M_Y, M_C, dM). Combined with the tristimulus values XYZ reliable quality control of black colors can be achieved.

Abbildung 4 Fluorescent slider to compare different materials

Abbildung 5 Data table and line chart displaying Jetness indices

5. Powerful SQC database with data sharing

In a global world, efficient data sharing between different production sites and among the supply chain is essential. Thus, when a project has been completed, the measurement data can be saved in a powerful SQL database which allows handling of large data sets over a long period. The database can either be stored locally or recite on a SQL server with defined access rights for the individual users. All reports can be sent to Excel, printed out or sent by email as a PDF file.

6. Summary

Color and gloss control in the laboratory requires a high degree of flexibility in data analysis on the one hand, but also efficient data handling of large data sets on the other. 
BYK-Gardner’s software smart-chart offers unsurpassed functionality to make you ready for professional BIG DATA management: 

• Powerful standard management with digital master standard distribution
• Measurements can be taken online or transferred from the instrument memory
• Professional project management to organize measurement data
• Standard QC reports: data table, CIELAB scatter plot, trend line and spectral curve
• Powerful SQL database for efficient data handling over a long period

smart-chart has all the tools to make the world of data analysis transparent, easy to interpret and efficient. Make sure to always have the latest version installed on your computer: https://www.byk-instruments.com/en/software.