In the page die creasing and perforating machines, we had widely explained what is required to obtain quality die creased and perforated jobs. When doing high quality jobs, using heavyweight paper (for automobile and furniture catalogues or mobile phones and computer brochures etc …) sheets generally make up a booklet with a pattern of parallel folds and not with signatures.
For high-quality and accurate results, sheets must be creased and folded. Usually creasing operations are done by typo machines or die cutters, and folding operations are carried out manually.
Petratto’s CORDOBA line of machines is able to crease and fold all these kinds of jobs in a perfect way, even when thickness is up to 600 g.
Sometimes, it may happen that inner sheets have folding patterns that cause paper jams in the next processing steps; for example a Z-fold sheet may cause a paper jam if the flap opens when crossing over the transportation chain.
high-stock covers* with flaps, or too short flaps that tend to open, cause problems as the one described above.
The machines belonging to CORDOBA line crease, fold and apply a small line of glue on one edge. In this way, the flaps are kept closed while the sheet is moving; this line of glue is eliminated during the trimming phase.
The CORDOBA line of machines has been designed to die crease face down and face up, to process many types of paper and cardboard with the fiber both on the short and long side, and generally any type of paper and cardboard, even laminated, UV-varnished or digitally printed papers.
*A cover with flaps is typical of perfect bound books. It is different from a traditional cover that has the same size of the book and will be trimmed, in the finishing phase, together with the book block itself. In perfect bound books, flaps are two lateral stripes whose width generally varies from a few centimeters (6-10) to almost the entire width of the cover. These flaps fold up inside the cover and here the book presentation is printed, sometimes with also the caption of the cover illustration and a biographic or bibliographic note of the author.