Patent ID: 6322657
Filing Date: 2001-11-27
Classification: B29C,B29K,G09F,Y10T

Abstract:
A method of joining at least two translucent sign face substrates with a seam tape to form a seam having a transmissive optical density within.+-.about 25% of the transmissive optical density of the sign face substrate when the sign face is illuminated from behind the sign face substrate, said method comprising the steps of:(a) providing at least two sheets of sign face material, such that each sheet comprises a composite of two layers of a thermoplastic material and a scrim layer sandwiched between the two layers of thermoplastic material;(b) aligning said two sheets such that an edge of each sheet is in an adjoining position and defines an adjoining region without any gaps between the adjoining sheets of sign face material;(c) positioning a seam tape in said adjoining region such that a portion of said tape simultaneously overlays and contacts each sheet within the adjoining region and extends substantially the length of the adjoining region, said tape comprising a seam scrim substantially embedded in a seam thermoplastic material having an index of refraction similar to the scrim of the seam tape, said seam scrim capable of being substantially wetted out by said seam thermoplastic material;(d) heating said adjoining region to a temperature which exceeds the melting temperature of said seam thermoplastic material;(e) exerting sufficient pressure to said heated region to substantially wet out said scrim; and(f) allowing said region to cool.