Patent ID: 8403820

Claim:
A method of making reinforced paperboard cartons comprising the steps of: (a) advancing a web of paperboard along a path, the web of paperboard having a width; (b) progressively applying at least one ribbon of reinforcing material to the advancing web of paperboard to form a reinforced region for the carton, the ribbon having a width less than the width of the web of paperboard and an edge; (c) forming at least one fold line in the web of paperboard, the at least one fold line extending transversely to the reinforcing region and crossing the edge of the ribbon of reinforcing material to define (1) a first section within the reinforced region and a second section outside the reinforced region, the first section of the at least one fold line being wider than the second section of the at least one fold line, and (2) a transition zone between the first and second sections of the at least one fold line; (d) the at least one fold line being formed by (i) positioning the paperboard between a multi-point scoring rule having a narrower scoring rule section outside the reinforced region and a wider scoring rule section inside the reinforced region and a counter plate located beneath the scoring rule, the counter plate including a groove aligned with the scoring rule, the groove having a narrower groove section aligned with the narrower scoring rule section, and a wider groove section aligned with the wider scoring rule section, the groove gradually widening from the narrower groove section to the wider groove section to form the transition zone, and (ii) impressing the paperboard with the multi-point scoring rule to form the at least one fold line.