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(11) | EP 0 279 609 A3 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Manufacturing corrugated board |
| (57) A conventional single faced corrugated board manufacturing plant is modified to produce
corrugated board having two fluted mediums bonded at their flute tips. In addition
to the existing corrugating rolls (10, 11) a further pair of corrugating rolls (34,
35) synchronized with the existing pair are provided so that the corrugated mediums
(22, 23) are contacted at their flute tips. An additional mill roll stand is provided
for the second fluted medium. A carrier roll (36) is provided adjacent to the pairs
of corrugating rolls to take off the bonded fluted mediums and provide support and
prevent uncontrolled movement of the flute to flute structure during the development
of the adhesion bond. Adhesive applicators (37) are provided to apply adhesive to
one of the mediums prior to the flute tip to flute tip bonding and to coat the flute
tips of the bonded fluted structure on the carrier roll for bonding to the inner (21).
An additional guide roll (38) is provided to allow tangential approach for the liner
onto the flute to flute structure carried by the carrier roll. Radiant energy is used
to assist in bonding the inner to the flute to flute tip structure enabling a low
pressure bonding technique to be used. |