Wetting measurements at high temperatures with the MobileDrop HT

For cooking utensil coatings the usual test methods are both natural and casual: The tester fries eggs or steaks and checks their adhesion. There is no trace of a quality assurance standard. The disadvantages are obvious: From a chemical viewpoint one egg is not the same as the next one – the result depends on uncontrollable factors. The test also only provides two results: The fried food either sticks to the coating, or it doesn’t.

In contrast, contact angle measurements on the coated surface with the MobileDrop permit a quantifiable check of wettability using test liquids that are always chemically identical - either hydrophobic or hydrophilic, as required. In order to make measurements on the base area, which is surrounded by the sidewalls, the instrument utilizes a special optical arrangement which reduces the space requirements to a few square centimeters. New in the KRÜSS range is the high-temperature version MobileDrop HT for wetting measurements under conditions of use - for comfortable measurements for five to ten seconds at temperatures up to 250°C . 

Fine dosing device DS3601 for the MobileDrop contact angle measuring instrument

The contact angle is an intrinsic parameter of the solid/liquid phase boundary that does not depend on the amount of substances in the participating phases. Notwithstanding this, measuring procedures and standards frequently require an accurately reproducible drop volume. These demands are met by KRÜSS, who now provides the new fine dosing device DS3601 for the MobileDrop mobile contact angle measuring instrument. By using a micrometer a variable and exact dosing volume is generated and then deposited on the sample.  

The DSA14 is the basic instrument for manual wetting tests

The DSA14 basic instrument offers professional contact angle measurements at a low initial cost threshold. The smaller brother of the EasyDrop is the ideal instrument for manual material tests using static drops.

The drop volume is set manually and positioned on the sample by finger pressure using the new push-and-drop dosing*. The sample table height, illumination and focus of the lens are manually adjustable together with the viewing angle.

Even more measuring comfort is provided by the versatile possibilities of extending the DSA14. These include a pick-up table for detaching the drop from the needle, a manual dosing system for two liquids or a positioning table for fine adjustment of the horizontal sample position.

For analyzing the shape of static drops and calculating the surface free energy the DSA14 offers the same possibilities as high-performance KRÜSS instruments – this is ensured by the inclusion of the well-proven DSA software.

DSA14 in overview

• Manual single or double dosing
• Lens with fixed focal length and adjustable image sharpness (optionally with 6-fold zoom)
• Camera with IEEE1394 interface with 20 fps (optionally with 60 fps)
• Manual control of sample height, optionally as pick-up table or with lifting table
• Manual illumination controller
• DSA software with five different drop shape analysis methods and various models for calculating the surface free energy

* Also available for the EasyDrop series