Drop Shape Analyzer

From one-click wettability measurement to analysis of solid-liquid adhesion

In its Expert configuration, the DSA25 Drop Shape Analyzer is designed for determining the wettability of solids by means of the contact angle as well as the surface tension of liquids such as coating substances or adhesives. Thanks to the combination of speed and versatile evaluation options, the analyses give quick feedback to pretreatment steps in quality control but also allow assessing the resulting adhesion.

Applications

• Quality assurance of activation processes such as plasma treatment, flame treatment, or corona treatment

• Checking wettability of plastics, glass, ceramics, wood, paper, or metal

• Testing the effectiveness of hydrophobic coatings and other coatings

• Analyzing coating liquids and adhesives and assessing their adhesion

• Assessing long-term stability of coatings

• Analyzing (super-) hydrophobic and self-cleaning surfaces

• Wetting analysis at controlled temperature and/or humidity

Measuring methods

• Contact angle of a drop on a solid surface
• Contact angles of two drops dosed in parallel
• Contact angle using a gas bubble beneath a solid surface in a liquid
• Roll-off behavior and advancing/receding contact angle of a drop on a tilted surface
• Surface free energy of a solid using contact angle data
• Surface or interfacial tension using the curvature of a drop or bubble at the tip of a needle
• Surface tension using the curvature of a perfectly symmetrical drop on a circular sample pedestal
• Calculating adhesion-related scientific parameters for the interfacial contact
• Calculating the polar and disperse part of the surface tension from contact angle and surface tension data
• Contact angle at an immersed, cylindrical sample, usually a fiber
• Carrying out a measurement up to 20 consecutive times and displaying the results together
• Measuring the recently receded contact angle to characterize dewetting behavior

Measuring results

• Static contact angle

• Advancing and receding contact angle

• Contact angle using a bubble in a liquid

• Roll-off angle

• Surface free energy (SFE) according to the following models: Owens-Wendt-Rabel-Kaelble (OWRK), Fowkes, Wu, Zisman, Equation of State

• Surface tension of a liquid and interfacial tension between two liquids

• Work of adhesion, solid/liquid interfacial tension, spreading coefficient

• Temperature