2. Material selection: the choice of cardboard material is an important part of the strength design, it not only affects the printing effect, but also has a bearing on the physical properties of the finished corrugated boxes. For example, there is a close relationship between the water content of the paper and the strength of the carton. While choosing paper to use, different weather conditions must be considered. And paperboard produced must also meet the requirements in terms of physical properties such as breakage resistance, side pressure and adhesion.
An important reason for the popularity of cardboard packaging is their environmental benefits. Thus the use of consumables like ink, additives, polishes, and the recycling properties of paperboard itself must be in compliance with environmental requirements. And when used for packaging food, medicine or children's toys, the cardboard boxes must also meet the requirements of hygiene, health and safety. Of course, in case of export, it is necessary to consider the relevant laws and regulations of the destination country.
3. Size: In designing the box size, in addition to the reasonable length, width and height ratio according to the contents, designers should also consider the right container types to make full use of packaging space.
4. Printing process problems: designers need to pay attention to the difference between various printing processes. The printing methods commonly used in corrugated boxes in China mainly include offset printing, silkscreen printing, flexo printing, and gravure printing etc. Changes in printing methods directly affect other processes, and even result in change of print materials. For example, it’s difficult to use water-based ink flexographic printing over coated paper. When using the popular flexo printing process, it is necessary to pay attention to the layout.
With flexo printing, thin lines, small texts, and patterns with dots should not be arranged on a layout with a large-area flush color background. Because the full-page flush color background printing requires a larger printing pressure, it is easy to make small text and pattern deformation, causes printing problems like blurring, broken lines, missing font strokes, and dot loss, etc. and will result in premature wearing or damage of the printing plate. If they had to be in the same page, then the exposure time should be extended to improve the hardness and printing durability of the plate at the fine image.
In order to overcome the unevenness and roughness of the cardboard surface, the printing plate is required to be wear-resistant, strong in impact resistance, moderate in hardness, good in resilience after being pressed, uniform in ink and thickness. Based on the pattern, the size of the text, lines and the material of the corrugated board, change the layout, hardness and making methods of the flexo plates accordingly. When the corrugated board is of poor quality or with full page background printing, thicker and softer flexo plate should be used. When the corrugated board has good quality or printing fine patterns and small characters, choose harder and thinner or resin flexo plates.
If the printing surface of the corrugated board is uneven, rough, warping and with other problems, it may cause filling in(糊版), crush, wearing or damage to the flexographic resin plate. Therefore, the quality of the base paper should be strictly controlled in the printing process of cardboard gift boxes.