Method and apparatus for applying pressure sensitive labels to hollow containers

In a method for applying pressure sensitive labels to products such as hollow articles by moving the label carried on a label web and providing for an acute bend of the label web to transfer the label to a hollow article, the improvement comprises heating said label directly to elevate the temperature above ambient temperature before the acute bend to warm the label sufficiently to permit the pressure sensitive adhesive on the label to flow sufficiently to enter the microscopic surfaces of the hollow article. In one form, the heating comprises directing warm air directly against the label while it is on the label web. In another form, heating said label comprises providing a heating plate in direct contact with the label web on the surface of the label web opposite to that on which said label is carried. The apparatus comprises means in advance of the acute bend for heating said label while it is carried by the label web directly to elevate the temperature above ambient temperature before the acute bend to warm the label sufficiently to permit the pressure sensitive adhesive on the label to flow sufficiently to enter the microscopic surface irregularities of the surfaces of the hollow article. In one form, the heating means comprises plenum means for directing warm air directly against the label while it is on the label web. In another form the heating means comprises a heating plate means in direct contact with the label web on the surface of the label web opposite to that on which said label is carried. The apparatus includes means for moving the heating plate means into and out of contact with the web.