The quality requirements for box gluing are: accurate gluing alignment, no skew, firm gluing, no debonding, no inner or outer overlap, no scratches on the printed surface or obvious scratches and stains, easy to open, no cracked lines or corners.
(1) The interface position of the box gluing machine must be aligned, especially for boxes with matching patterns. This should be paid more attention to, otherwise it will affect the appearance of the box. Some paper boxes are shorter than their width and length (flat type), which can easily cause paper feed skew during gluing, making the overlap misaligned.
(2) Firm gluing, no debonding. About 12 hours after gluing, when the glue is completely dry, tear off the edge of the gluing paper and tear off one side of the paper (usually the fiber on the back of the paper, commonly known as breaking the skin) to pass. Otherwise, it proves that the gluing is not firm. Nowadays, many printed surfaces have been treated with varnishing, calendering, UV varnish, lamination and other surface treatments. If this is not paid enough attention to or not specially treated during the pasting process, it is very easy to cause poor adhesion and debonding.
(3) Inner and outer bridging. Inner bridging means that after pasting, glue overflows from the inner edge of the box, causing the inner and outer sides of the box to stick together, making the box difficult or impossible to open. Outer bridging means that after pasting, glue overflows from the outer edge of the box, causing the boxes to stick together, leaving glue marks on the box surface after separation. If the outer bridging is serious, the printed surface will be torn when it is separated. Therefore, both inner and outer bridging will have a serious impact on the quality of the box. If it is delivered to the customer, it will cause trouble for the customer to use it, especially if it cannot be used on the automatic packaging machine, which will inevitably lead to returns and is extremely difficult to rework. It will cause great losses to the company.
(4) The box gluing machine scratches the printed surface or leaves scratches or dirt. During automatic box gluing, mechanical friction can easily scratch the ink layer on the box surface, leaving scratches and sometimes dragging ink onto blank areas, causing stains. Some products are printed on both sides. During box gluing, it's very easy for the reverse ink to rub onto the front of the box at the front, causing stains. In severe cases, the product must be scrapped.