An apparatus for applying a liquid to threads of a yarn sheet comprising multiple thread wetting elements, multiple thread guide grooves each having a thread feed end and a thread exit end, each of said thread wetting elements having associated with it at least one of said thread guide grooves, multiple liquid feed bores or grooves for supplying said liquid one of which terminates in each of said thread guide grooves, a liquid distributor which is implemented as a support to which said thread wetting elements are attached and which supplies liquid feed to each said liquid bore or groove, each of said threads of said yarn sheet traveling within one of said thread guide grooves with said liquid, the direction of travel of said threads being from said thread feed end to said thread exit end of said thread guide grooves, there being a separation of adjacent thread guide grooves of from 2 to 30 mm, and adjacent thread guide grooves being different distances from said liquid distributor such that said thread guide grooves are offset in an alternating manner.