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Different behavior of two coatings in the regeneration phase is illustrated by Table 3.3.

Analysis: Coating 1 shows complete regeneration within 120 s already (related to the viscosity value). This may facilitate to obtain the required wet layer thickness. Here, with 87 % structural recovery attained after 30 s the final structural strength has almost been reached already. Coating 2 displays a slower structural regeneration, showing a long lasting and therefore good leveling behavior. However, this coating may show a certain tendency to sagging on vertical areas, which may prevent to achieve the desired layer thickness.

For more information on tests to evaluate thixotropic behavior, see Chapter 8.5.2.2 (using oscillatory tests). Corresponding analysis can be performed in an adapted form for rheopexy and rheopectic behavior. However, this behavior is hardly occurring in industrial practice (see also the Note in Chapter 3.4.2.1c: shear-induced increase in viscosity).

Table 3.3: Regeneration of two coatings in terms of η(t) and in % (after a high-shear interval)
	Coating 1	Coating 2
	η [Pas]	Reg. [%]	η [Pas]	Reg. [%]
at the end of the first interval, at low-shear conditions; the reference value of the viscosity-at-rest	15	100	30	100
at the end of the second interval, at high-shear conditions	0.5	(3)	1.0	(3)
regeneration in the third intervalafter t = 30 safter t = 60 safter t = 120 s	131415	8793100	41015	133350

Figure 3.42: Preset of a time-dependent shear rate profile consisting of three test intervals: upward ramp, high-shear phase, and downward ramp