Paperboard cartons with laminated reinforcing ribbons and method of printing same
View Patent ↗A method of making reinforced cartons comprises the steps of advancing a length of carton material along a path and progressively laminating at least one ribbon of reinforcing material to the advancing length of carton material. The ribbon of reinforcing material generally has a width less than the width of the length of carton material and is applied with adhesive at a selected location(s) across the width of the length of carton material. The web and its laminated ribbon are cut into sheets of a predetermined size and the sheets are die-cut and scored with fold lines to form carton blanks. The fold lines may transition from non-reinforced to reinforced portions of the blank and a special transition zone is contemplated to accommodate the transition. The carton blanks are subsequently formed into cartons for receiving articles, the laminated reinforcing material providing reinforcement in selected portions of the cartons. Multiple ribbons and multiple layers of ribbons may be laminated to the web in respective selected locations to provide reinforcement in more than one portion of the cartons. Reinforcing ribbons may be deformed or altered to exhibit, for instance, corrugations or perforations prior to being adhered to the base sheet.
1. A method of preparing reinforced carton blanks, comprising:
moving a series of carton sheets toward an engaging position along a processing path, with each of the sheets having a desired grain orientation to enable an optimal number of press repeats per carton sheet;
moving at least one strip of a reinforcing material toward registration with each of the sheets, with the at least one strip of reinforcing material having a grain orientation aligned with the grain orientation of the carton sheets;
applying an adhesive material between each sheet and an associated strip of reinforcing material;
attaching each sheet to its at least one associated strip of reinforcing material; and
cutting the attached carton sheet and the associated reinforcing material to form carton blanks.
2. The method of claim 1 and wherein applying an adhesive material comprises applying the adhesive to an upper surface of the strip of reinforcing material prior to the strip and sheet moving into registration.
3. The method of claim 2 and wherein applying the adhesive comprises spraying the adhesive onto the strip of reinforcing material.
4. The method of claim 2 and wherein applying the adhesive comprises passing the at least one strip of reinforcing material adjacent an applicator roller and engaging the upper surface of the strip of reinforcing material with the applicator roller to apply the adhesive thereto.
5. The method of claim 1 and wherein moving the series of sheets comprises placing a stock of sheets in a hopper and feeding each sheet from the hopper toward its associated strip of reinforcing material.
6. The method of claim 1 and further comprising feeding a reinforcing material from a supply, cutting the reinforcing material into desired widths and segmenting the reinforcing material at desired lengths to form the strips of reinforcing material.
7. The method of claim 1 and wherein moving at least one strip of reinforcing material comprises guiding a series of spaced strips of reinforcing material along a processing path toward the sheet, with each of the strips maintained in a spaced relationship separated from each other by a series of spaced guides.
8. The method of claim 1 and wherein attaching each sheet to its at least one associated strip of reinforcing material comprises passing each sheet and its at least one associated strip of reinforcing material between variable pressure rollers and urging the sheet and its at least one associated strip into adhesive engagement.
9. The method of claim 8 and wherein urging each sheet and its at least one associated strip of reinforcing material together comprises applying a minimum pressure sufficient to cause adhesion to the sheet and its at least one associated strip of reinforcing material.
10. The method of claim 1 and further comprising stripping excess sheet and reinforcing material from the formed carton blanks.
11. The method of claim 1 and further comprising printing on at least one surface of the sheets.
12. The method of claim 11 and wherein the step of printing comprises passing the sheets with the strips of reinforcing material between at least one print roll and at least one impression roll having a recessed portion in which the strips of reinforcing material are received and pass as the print roll engages the sheets.