US 12,360,030 B2
Method and apparatus for measuring a receding contact angle
Thomas Willers, Hamburg (DE); and Katrin Oetjen, Schenefeld (DE)
Assigned to KRÜSS GmbH, Hamburg (DE)
Filed by KRÜSS GmbH, Wissenschaftliche Laborgeräte, Hamburg (DE)
Filed on Jun. 22, 2022, as Appl. No. 17/846,108.
Claims priority of application No. 21181439 (EP), filed on Jun. 24, 2021.
Prior Publication US 2022/0412863 A1, Dec. 29, 2022
Int. Cl. G01N 13/02 (2006.01)
CPC G01N 13/02 (2013.01) [G01N 2013/0208 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A method for measuring a receding contact angle between a sample surface and a drop of a liquid, the method comprising:
ejecting a dosing volume of the liquid from an opening onto the sample surface, wherein the liquid is ejected as a continuous jet at a defined flow rate for a defined dosing time period, wherein the opening comprises an opening diameter;
allowing the dosing volume of the liquid to form a drop on the sample surface;
measuring at least one geometrical parameter of the drop formed on the sample surface; and
determining the receding contact angle between the sample surface and the drop based on the at least one geometrical parameter,
wherein the flow rate and the dosing time period are selected such that the dosing volume does not exceed the flow rate multiplied by 0.11 s.