Extrusion method and apparatus

A process for extruding a thermally activatable material onto a substrate comprising:

• (a) feeding the thermally activatable material into an extruder via a feed section, which compresses and moves the thermally activatable material to an extrusion screw;
• (b) moving the thermally activatable material along the extrusion screw, operating at 10 to 50 revolutions per minute, within a barrel of the extruder, the barrel having a length to diameter ratio of 20 to 16, through one or more zones by rotating the extrusion screw;
• (c) passing the thermally activatable material from the extrusion screw through an extrusion die as a molten material;
• and
• (d) extruding the thermally activatable material onto the substrate at a temperature below an activation temperature, where the thermally activatable material bonds to the substrate and cools;
• wherein the extrusion screw rotates in a clockwise direction and a counterclockwise direction to create a discontinuous pattern or array of the thermally activatable material having one or more gaps free of the thermally activatable material;
• wherein the thermally activatable material is engages with grooves formed in the barrel and;
• equally spaced around an internal diameter of the barrel along a length of the extrusion screw;
• and
• wherein a residence time of the thermally activatable material in the barrel is less than 10 minutes.