Applying heated polymer composition, e.g. hot melt adhesive, to substrate - passing composition through nozzle that combiners flow path of compostion with optical path of beam of electromagnetic energy obtained from YAG laser

摘要

Method and apparatus for applying a hot composition to a substrate. The method includes providing a flow path through which the composition is distributed over the substrate, irradiating said composition with a flash of energy directed along the length of the flow path. The apparatus includes the flow patch (11) for an extrudable material (1), which is applied through the nozzle (13) a radiation source (8) gives a flash (9) through the optical window (12) to the composition supplied through the flow patch (11). IMAGE An extrudable material (1), e.g. a hot melt adhesive, is applied to a substrate with simultaneous irradiation by a laser beam (9). The energy of the laser is absorbed by the adhesive and the substrate to cause the adhesive to spread into the fabric. When applied to a gap between two substrate sheets, the extrudable material creates a very strong bond. When one of the substrate materials is porous, the extrudable material will penetrate the thickness of the material and contact a lower layer to form a bond. The extrudable material is applied through a nozzle, and the laser beam is directed through the nozzle to be coaxial with the flow path (11) of the excludable material. The coaxial arrangement facilitates movement of the nozzle and beam in complicated patterns and ensures simultaneous application of the extrudable material and the laser beam. Pref. the substrate is attached to an X-Y table that is driven by digital linear motors and controlled by a computer.