Method of forming single face corrugated board

A method of transferring discrete droplets of an adhesive to a corrugated sheet material comprising:

• applying said adhesive to a roller at an ambient temperature of 5° C. to 30° C., and
• transferring said adhesive to said corrugated sheet material,
• wherein the roller comprises a contoured outer surface having a series of grooves and ridges alternately positioned there along and encircling the outer surface of the roller;
• wherein a depth of the grooves is substantially 0.5 mm and a width of the grooves is substantially 1 mm, wherein an axis of the grooves intersects an axis of the corrugations of the sheet material such that discrete pear shaped or round shaped droplets of adhesive having a predetermined size are applied to crests on the corrugated sheet material, via troughs of the roller, upon contact being made there between, and wherein the discrete droplets applied to the crests on the corrugated sheet material are spaced with gaps between the droplets, such that compression of the droplets between the corrugated sheet material and a planar sheet results in the compressed droplets just meeting each other.