Reinforced pocket structure for thermo-adhesive materials

A photo finisher wallet comprising:

• a first flexible thermo-adhesive sheet foldable to form a front cover portion and a rear cover portion, one of said cover portions being substantially rectangular and having a welded seam along three edges thereof;
• a substantially rectangular second flexible thermo-adhesive sheet sealed along three edges thereof to the inner surface of said substantially rectangular one cover portion by said seam and having an unsealed edge to form a pocket having an opening;
• a first reinforcing weld sealing said sheets at a first corner of said pocket at said opening, said first weld inwardly extending from said seam and having at least a portion thereof inwardly tapered toward a thickened termination of said first weld;
• and
• a second reinforcing weld sealing said sheets at a second corner of said pocket at said opening, said second weld inwardly extending from said seam and having at least a portion thereof inwardly tapered toward a thickened termination of said second weld.

A reinforced pocket structure comprising:

• a substantially rectangular first flexible thermoadhesive sheet having a welded seam along three edges thereof;
• a substantially rectangular second flexible thermo-adhesive sheet sealed along three edges thereof to said first sheet by said seam and having an unsealed edge to form a pocket having an opening along said unsealed edge;
• a first reinforcing weld sealing said sheets at a first corner of said pocket at said opening, said first weld inwardly extending from said seam and having at least a portion thereof inwardly tapered toward a thickened termination of said first weld;
• and
• a second reinforcing weld sealing said sheets at a second corner of said pocket at said opening, said second weld inwardly extending from said seam and having at least a portion thereof inwardly tapered toward a thickened termination of said second weld.

A reinforced pocket structure comprising:

• a substantially rectangular first flexible thermoadhesive sheet having a welded seam along three edges thereof;
• a substantially rectangular second flexible thermo-adhesive sheet sealed along three edges thereof to said first sheet by said seam;
• a substantially rectangular third flexible thermoadhesive sheet sealed along three edges thereof to said second sheet by said seam and having an unsealed edge to form a pocket having an opening along said unsealed edge;
• a first reinforcing weld sealing said sheets at a first corner of said pocket at said opening, said first weld inwardly extending from said seam and having at least a portion thereof inwardly tapered toward a thickened termination of said first weld;
• and
• a second reinforcing weld sealing said sheets at a second corner of said pocket at said opening, said second weld inwardly extending from said seam and having at least a portion thereof inwardly tapered toward a thickened termination of said second weld.

A high frequency welding method for sealing two thermo-adhesive sheets along a welded seam to form a pocket having an opening, comprising the steps of:

• providing a high frequency welding press having a lower electrode platen and an upper electrode die, said upper electrode die having a seam producing die surface for producing said welded seam, said die surface including a first widened die surface portion inwardly extending and downwardly inclined from said seam producing die surface and a second widened die surface portion inwardly extending and downwardly inclined from said seam producing die surface;
• superposing said thermo-adhesive sheets and interposing said sheets between said lower electrode platen and said upper electrode die with an edge of one of said sheets positioned such that said first widened die surface portion overlies a first junction of said edge and said seam when produced and said second widened die surface portion overlies a second junction of said edge and said seam when produced;
• and
• engaging said upper die surface portion into pressure contact with said interposed sheets while applying a high frequency dielectric field between said electrode platen and said electrode die and thereafter releasing said die to produce said seam.