Breathing sheet material having an adhesive coating layer and manufacturing method therefor

The invention relates to a breathing adhesive sheet material comprising a sheet layer having apertures and an adhesive coating layer with apertures corresponding to at least part of the apertures of said sheet layer, provided on one side of said sheet layer having apertures, wherein said apertures in said adhesive coating layer constitute portions of a substantially continuous adhesive coating layer separated there from by remaining adhered to a protective sheet layer upon removal thereof. The invention also relates to a composite sheet material comprising such adhesive sheet material with a removable protective sheet layer provided to separate portions from the continuous adhesive layer upon separation thereof from the adhesive sheet material. The invention also relates to a method for manufacturing such an adhesive sheet material comprising the steps of applying a layer of uncured adhesive material to a sheet layer having apertures and a layer of protective sheet material, and submitting the sheet layer having apertures, the layer of protective sheet material and the layer of uncured adhesive material to a curing operation, thereby causing the layer of adhesive material to preferentially adhere to the sheet layer having apertures outside the apertures, and to adhere to the protective sheet layer at said apertures.