Patent ID: 6871477

Claim:
A continuous process for forming a transdermal patch holding an active substance, said process comprising the steps of: continuously feeding at a linear speed a first strip of materials comprising a disposable layer, a layer of adhesive and a layer of a permeable membrane permeable to the active substance; continuously feeding in close proximity and in face-to-face relationship with the first strip at least one second strip formed of impermeable backing material(s), at the same linear speed; passing the first and second strips together through a first sealing station at which at least the opposed longitudinal edge regions of the strips are secured together; passing the first and second strips joined at least at their longitudinal edges, through a second sealing station at which the strips are sealed to each other transversely at intervals along the strips, whereby the or each chamber becomes an open-topped pouch; introducing an accurate predetermined dosage of a liquid or gel containing an active substance into the pouch or pouches, once formed, in synchronous with the linear speed; and sealing the pouches along their previously open edges so as to form completely sealed pouches thereby forming the transdermal patch.