摘要 |
In a carton for liquids folded from a sheet of packaging material wherein the carton has a lapped seam with a protected edge, the improvement which comprises providing the protected edge with a wedge-like tapered profile, whereby the thickness of the sheet material is reduced along the protected edge. The sheet material carries a thicker protective coating on the inside of the carton and a thinner coating on the outside. The seams are lapped by various configurations of the wedge, depending upon which face is undercut. |