There are many methods of applying printed images to corrugated boxes. All below methods are commonly used, but serve different purposes and budgets.
FLEXOGRAPHIC PRINTING
This method of printing on corrugated board is often executed on the same machine and at the same time in-line as it converts a corrugated pad into a box. Flexography uses flexible rubber or polymer plates to transfer an image onto corrugated board much like a mechanized rubber stamp. Fast-drying, water-based inks are generally used, which allow for fast running speeds. The print quality is dependent on many variables, and is influenced by the absorbency of the material being printed. By nature, corrugated material is highly absorbent and thus flexo printing is used for straight text or 1-2 colour graphical images and not recommended for high definition graphics.
SCREEN PRINTING
Screen printing is a process of forcing ink through a tight screen which is mounted on a frame. The screen carries a stencil which defines the image area and is made of porous material which allows for full ink coverage on corrugated board. The board is generally screen printed prior to its conversion into a box or display.
LITHO-LAMINATING
The method of litho-laminating involves the printing of a sheet of paper by an offset or digital printer. A wide range of embellishments, such as laminating, varnishing, foil stamping, embossing/debossing, spot UV, can also be applied. The printed paper is later glued to the corrugated board using a water-based adhesive. The litho-laminated board is then converted into the box. This process results in very high definition, sharp images with the ability to produce bright colours. Litho-laminated boxes are appropriate for those who are looking for a high quality finish to their corrugated packaging and is often used for retail packaging or Point-of-Sale displays.
PRE-PRINT
This is where the outside liner is printed (in roll form) before it is converted into corrugated sheets. By preprinting the liner before it is converted, this process provides high-quality images, color consistency and good color saturation. However, this process is most suitable only in very high volume runs since a lot of investment goes into the process. This i one of most popular mediums of printing on corrugated boxes in the food and beverage industry.
LABEL STICKERS
If you work on low quantity runs, label stickers are one of your best options. Printed label sheets are glued to the outer surface of the corrugated material. A glossy finish to the print can be achieved and hence a neat professional appearance can be observed.