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for η1 = 100 mPas after t1 = 10 s, and η2 = 300 mPas after t1 = 60 s, results:

VR = 100/300 = 0.333

M2) The total thixotropy time

The total thixotropy time is determined as the time difference between t2 at the end of the second interval indicating structural decomposition in terms of ηmin, and the time point in the third test interval when reaching the maximum value ηmax after structural regeneration. Thus, the total thixotropy time is the period of time required for the complete (100 %) regeneration, i. e. when reaching again the reference value of the viscosity-at-rest which was determined in the first test interval. Of course, this period of time might be shorter than (t3 – t2) if regeneration is finished already before time point t3 is reached.

M3) The relative thixotropy time required to reach a certain percentage of regeneration

For QC tests, analysis of the total thixotropy time according to method M2 may take a too long time. Therefore, then in the third test interval, the relative thixotropy time is determined as the period of time for the η-value to reach the relative value of, for example, 75 or 90 % compared to the reference value obtained in the first interval (which counts as the “100 % η-value” here).