DEVICE FOR STRETCHING LAMINATING INTERLAYERS

摘要

DEVICE FOR STRETCHING LAMINATING INTERLAYERS An apparatus for expanding a laminating interlayer includes structure for feeding and heating a continuous web of interlayer material. The heated interlayer is fed from the heating structure to a cooling roll rotatably driven by a drive structure. The cooling roll is mounted adjacent the heating structure in a position in which the web may pass from the heating structure to the cooling roll through a gap in which the web is unsupported. The drive applied to the cooling roll is effective to apply a stretching force on the web in the unsupported gap to expand the web in a controlled manner. The cooling roll has a surface shape in its axial direction which is in the form of a gradually changing or generally curved shape in which over a substantial length of the surface any tangent point on the surface projects to a different apex than the apex to which any other tangent point on the surface projects. This shape on the cooling roll allows its use in a stretching process to produce an interlayer having a selected radius of curvature.