This Standard describes a procedure for measuring the Euler number of coating colors using a High-Shear Viscometer with an orifice configuration. In this method, the extensional viscosity is evaluated by calculating the Euler number when the coating color flows through an orifice at a velocity of 15 m/s. The method is applicable for water-based coating colors used in various coating processes such as in blade, rod, and curtain coating. Typically, suitable coating colors have a solids content between 30 % and 80 %, and they contain mineral pigments, synthetic and / or natural polymers, and coating additives. A Euler number of 1-2 signifies a lack of extensional viscosity in the sample. Euler numbers of 2-5 signify moderate amounts of extensional viscosity, while numbers over 5 signify high extensional viscosity. Typical extensional viscosity values can be seen in Appendix E.

Date of Publication: May 16, 2024

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Working Group Chair: Martti Tuomisto, EPIQ - Advanced Dynamics Corp.

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