A method of manufacturing a bituminous coating sheet, wherein a bitumen-impregnated core material provided with a layer of backface bitumen is caused to be in contact with one or more rotating bodies during the manufacture. A slip material dispersed/emulsified or dissolved in a liquid is applied onto the bituminous backface layer on the side that is to be brought into contact with a rotating body; and that the liquid is evaporated prior to contact with the rotating body; and that subsequently a further bituminous layer is applied onto the side which is provided with said slip material.
展开▼