biostudies-literatureSaiseau REuropean Research CouncilAgence Nationale de la Recherche (French National Research Agency)7442https://www.ebi.ac.uk/biostudies/studies/S-EPMC9718839biostudies-literatureUnknown13(1)We study the spreading of droplets in a near-critical phase-separated liquid mixture, using a combination of experiments, lubrication theory and finite-element numerical simulations. The classical Tanner's law describing the spreading of viscous droplets is robustly verified when the critical temperature is neared. Furthermore, the microscopic cut-off length scale emerging in this law is obtained as a single free parameter for each given temperature. In total-wetting conditions, this length is interpreted as the thickness of the thin precursor film present ahead of the apparent contact line. The collapse of the different evolutions onto a single Tanner-like master curve demonstrates the universality of viscous spreading before entering in the fluctuation-dominated regime. Finally, our resuNature communicationsNear-critical spreading of droplets.PMC9718839101039103ANR-21-CE06-0029ANR-21-CE06-0039ERCCoG-101039103ANR-21-ERCC-0010-01ANR-15-CE30-0015-01Delabre UBenjana ADelville JPSaiseau RPedersen CSalez TCarlson AfalseNear-critical spreading of droplets.We study the spreading of droplets in a near-critical phase-separated liquid mixture, using a combination of experiments, lubrication theory and finite-element numerical simulations. The classical Tanner's law describing the spreading of viscous droplets is robustly verified when the critical temperature is neared. Furthermore, the microscopic cut-off length scale emerging in this law is obtained as a single free parameter for each given temperature. In total-wetting conditions, this length is interpreted as the thickness of the thin precursor film present ahead of the apparent contact line. The collapse of the different evolutions onto a single Tanner-like master curve demonstrates the universality of viscous spreading before entering in the fluctuation-dominated regime. Finally, our resu2022-01-01T00:00:00Z2022 Dec2025-04-21T16:41:26.198Z2025-04-21T16:41:26.198ZS-EPMC97188393646063310.1038/s41467-022-35047-1