Vent opening scoring in container lid

Abstract From the Canadian patent

A paperboard lid having first and second weakened score lines formed in the upper and lower faces thereof respectively. The score lines extend obliquely across the lid at a corner to form a frangible corner panel. The first score line is located between the corner and the second score line. A third weakened score line extends inwardly from the corner to the second score line. The path of the first and third score lines intersect one another at an intersection point, one of the first and second score lines is a discontinuous score line and the other is a continuous score line. The discontinuous score line is interrupted closely adjacent the intersection point such that the first and third …