PURPOSE: In a coating head to coat a web (continuously running and broad material such as plastic film) with a coating fluid, to uniformly spread the coating fluid in the direction of the coating width, by allowing the flow of the coating fluid in the coating head to expand temporarily by means of specific hollow portion provided at the passage of the coating fluid.
CONSTITUTION: A coating fluid 2 enters a coating head 1 at a feed orifice 4 through a supplying pipe 3 extending from a flow-regulating pump 9. The fluid is then spread along a spreading slot 6a into an inverted triangular shape with the feed orifice as its lower peak, so that the upper side of the inverted triangle has a width equal to an intended coating width. The coating fluid thus spread changes its direction along a parallel slot 6b while being spread over the width of the parallel slot 6b, passes through a slot opening 7, and is then applied to a web 8 on a coating roller 10. In this apparatus, around the upper terminal of the spreading slot 6a, a hollow portion 12 is provided as a chamber for distributing the coating fluid in the direction of the coating width, whereby the flow of the coating fluid is expanded temporarily and, hence, the coating fluid is spread uniformly in the direction of the coating width. Accordingly, formation of agglomerates and uneven coating with formation of lines therein can be prevented.
YUGAWA KIMIO
SUEFUJI MINEO
