摘要 |
<p>MANUFACTURING PROCESS FOR CHANNEL SEAL Molten thermoplastic, such as polyethylene, and a hot melt adhesive are coextruded through a channel shaped profile die. While still molten, the channel shaped strip, having adhesive between the ribs thereof, is brought into contact with a moving web of a thermoplastic e.g. polyethylene film, which is backed up by a roll at a controlled temperature. The temperature differential between the roll and the molten thermoplastic is maintained so that the thermoplastic adheres to the moving web upon contact and thereafter cools to set the thermoplastic in the channel shaped profile. The web is under tension so that contraction of the film upon release compensates for the contraction of the channel shaped strip as it cools.</p> |