Influence of Physical Properties of Water-Adjuvant Mixture on the Droplet Stains Depositing on an Artificial Target

The study was designed to determine the effect of adding different concentration of the adjuvant (0, 50 and 100% as compared to the recommended concentration from the adjuvant producer) on the surface tension of water from different sources and at different liquid temperature. As well as determining the stains spreading properties (area, diameter and coverage) on water-sensitive papers (WSP’s) after the drops from different mixtures released from two heights. The volume of the released drops during the test of stains spreading was kept unchanged and irrespective of the surface tension obtained. The results show that adding the adjuvant produced a change in surface tension of the working liquid. As the adjuvant concentration increased, the surface tension decreased which in turn increased the spreading (area, diameter and coverage) of the stain on the WSP’s especially at temperature of 10 ⁰C.