A method of spraying patterns on a web that includes directing at least
one intermittent spray of liquid onto the web to form a pattern on the
web; sensing a position of a leading edge of at least one of the spray
and the pattern relative to one or more references on the web; generating
a first correction signal when the leading edge is out of position; and
adjusting the spray of liquid in response to the first correction signal
to correctly position a leading edge of a subsequent pattern. The method
further includes sensing a position of a trailing edge of at least one of
the spray and the pattern relative to one or more references on the web;
generating a second correction signal when the trailing edge is out of
position; and adjusting the spray of liquid in response to the second
correction signal to correctly position a trailing edge of subsequent
patterns.