Contact angle measurement
Video-Based Optical Contact Angle Meter OCA 15+ from DataPhysics
For the software-controlled measurement and analysis of
- the static and dynamic contact angle according to the Sessile and Captive Drop method
- the analysis of the drop shape according to the Pendant Drop method
- the wetting behavior on solid surfaces
- the surface free energy of solids and their components
- the surface and interfacial tension out of the analysis of the drop shape
Consists of
- a dosing bay (with max. 4 syringe units)
- a single or multiple (max. 4) needle support
- a measuring stage, adjustable in three axis
- a lens mount with adjustable tilt
- a high-performance six-fold power zoom lens
- a video system with adapter and CCD-camera
- a high-performance video digitizing board (frame grabber)
- a illumination electronic system
- the SCA 20 software
Example
This measurement method makes it possible to evaluate the quality of surface pretreatment methods. For example the quality of an "easy to clean" coating can be analysed by the determination of the water contact angle as well as with the determination of the surface energy. With systematic analyses of coating substrates it is possible to optimise the surface pretreatment so that the hydrophobic properties of the coating layer correlate with the water contact angle, see the right figure.
without pretreatment
with pretreatment