接触角的测量-微小水滴在纸上

The FTÅ4000 can place very small drops on a sample and measure the contact angle. To
produce small drops, the instrument uses glass capillary needles and a piezo electric pump to
control the small volumes required. Two cameras are provided so the user can place the drops at
a precise location on the sample. Figure 1 shows a small drop ready to be placed on the sample,
which in this case is a printed business card. The width of the printing is measured to illustrate
the size of the drop (in the bottom of the "2"). The instrument can produce drops which are
considerable smaller than the one illustrated, but then the "weave" or roughness of the paper
becomes an issue in making contact angle measurements.