Abstract A closed edge corrugated core paperboard in which the corrugated core of the board is closed by slitting and compressing the corrugated core edge and by folding the edges of the facing sheets, left projecting after the core is crushed, one folded extending edge folded over the other folded extending edge, and adhesively securing the folded edges together; the method for producing such board including the steps of slitting and crushing the end of the core, folding the edges of the facing sheets, one over the other, and adhesively securing the folded edges of the facing sheets to each other; and, the apparatus for producing such board and for carrying out such method, which apparatus includes rotating slitter knives for slitting the end of the corrugated core, means for compressing the slit end and means for folding the extending facing sheet edges, one over the other, and for adhesively securing the folded edges to each other.
A method for forming an end closure on a paperboard having a corrugated core and facing sheets secured to the opposite sides of said corrugated core, the steps comprising, slitting the end of said corrugated core inwardly and substantially parallel to said facing sheets, compressing the slit end of said corrugated core inwardly so that, at said slit end, said facing sheets extend outwardly beyond said core, folding first one, and then the other, of said extensions of said facing sheets over said compressed end of said corrugated core so that the extension of one of said facing sheets is in contact with the compressed end of said core and the extension of the other of said facing sheets is in contact with and overlapping said folded extension of said one of said facing sheets, said folded extensions of said facing sheets being in a plane substantially normal to the planes of said facing sheets.
Claim 2
Dependent Claim
46 words
A method as recited in claim 2 including the further step of applying an adhesive to the outer side of said folded extension of said one of said facing sheets before the extending portion of the other of said facing sheets is folded into contact therewith.