Easydrop standard goniometer model fm140

A Konica CM-3600d Colorflex-DIFF2, from Hunter Associates Laboratory, Inc. (Reston, Virginia, USA) was used for the colour measurement. Colour coordinates (L*a*b*) were measured according to the following criteria: L* = 0, darkness; L* = 100, lightness; a* represents the green (a* < 0) to red (a* > 0); b* stands for the blue (b* < 0) to yellow (b* > 0) coordinate. The yellowness index for each sample was calculated according to ASTM E313. Colour measurements were carried out on standard tensile samples and, at least five different measurements of the colour coordinates were obtained and averaged.
Contact angle measurements were carried out with an EasyDrop Standard goniometer model FM140 (KRÜSS GmbH, Hamburg, Deutschland) which is equipped with a video capture kit and analysis software (Drop Shape Analysis SW21; DSA1). Double distilled water was used as test liquid. The wetting properties were evaluated on the surface of rectangular 80 × 10 × 4 mm³ samples. At least 10 measurements of the water contact angle were collected and averaged.

The interaction of the surface of the samples with the test liquid was measured by monitoring the wetting angles using an EasyDrop Standard goniometer, model FM140, supplied by KRÜSS GmbH (Hamburg, Germany). The equipment can measure contact angles from 1 to 180° with an accuracy of ±0.1°, using analysis software (Drop Shape Analysis SW21; DSA1).
In order to measure the contact angle in the equipment, the samples of the different fabrics were cut with a surface area of 25 × 25 mm². A drop of distilled water is deposited on their surface using a microsyringe. The contact angle is measured continuously until the drop is completely absorbed into the sample. At least ten measurements by drop and five different drops of distilled water were carried out for each fabric, and average values were calculated. The maximum error did not exceed 3%. The contact angle measurement over time (∆Θ·min⁻¹) was determined. To evaluate this value, the initial contact angle (Θ₀), the final contact angle (Θ_f), and the time elapsed in the test were measured. The experiment ended when the water droplet was completely absorbed or its contact angle decreased by at least 30°.

A Konica CM-3600d Colorflex-DIFF2 from the Hunter Associates Laboratory, Inc. (Reston, VA, USA) was used for the color measurement. The color coordinates (L*a*b*) were measured, with the illuminant D65 and observer 10°, according to the following criteria: L* = 0, darkness; L* = 100, lightness; a* represents the green (a* < 0)-to-red coordinate (a* > 0); and b* represents the blue (b* < 0)-to-yellow coordinate (b* > 0). The tests were run in triplicate.
Contact angle measurements were performed with an EasyDrop Standard goniometer model FM140 (KRÜSS GmbH, Hamburg, Germany), which was equipped with a video capture kit and analysis software (Drop Shape Analysis SW21; DSA1). Double distilled water was used as the test liquid. The tests were replicated 10 times.