Discussion on Offset Printing Technology of Micro-Corrugated Cardboard

First , the characteristics of direct offset printing micro-corrugated cardboard

The direct offset printing technology of micro-corrugated board has gradually matured with the development of new fine and fine corrugated cardboard, special blankets and inks. Offset printing is the most popular and most mature printing method in China, and the quality of printing is also widely recognized. We believe that this direct offset printing method will become a very strong marketing tool in China. However, this new technology is only applicable to fine corrugated cardboard, especially G-type and F-type micro-corrugated cardboard.

The direct printing of micro-corrugated cardboard has the advantages of high production efficiency, low material consumption, low production cost, large product specifications, wide application range, high strength of the carton, neat appearance, and favorable environmental protection, and is a main process for corrugated box printing. The global demand for this technology shows that it is increasingly accepted in offset printing and flexo printing. Even in the future, the print quality that can not be achieved by flexographic printing can be achieved in offset printing, because the letterpress printing has its limitations after all. The packaging industry continues to increase its print quality requirements. The packaging design further promotes the offset printing of fine corrugated cardboard in the performance of excellent product transportation and external packaging.

Pre-printing can be processed by printing methods such as flexo and gravure. This method can guarantee high printing quality and overprinting accuracy. The printing speed is fast and the yield is high. However, after printing, the web must be re-formed to form a roll print and then finely corrugated. The corrugated paperboard production line is used for the cutting of fine-cutting corrugated cardboard production lines. The cutting precision and requirements are therefore high, and this method is suitable for large quantities of products in the same batch. If the product variety is large, the batch size of the single product is not large. When using preprints, it is not ideal.

Corrugated carton industry in China is familiar with printing methods for printing corrugated and flexo-printed corrugated cartons, and the application is common, but it is relatively unfamiliar to preprinting and offset printing. However, with the gradual perfection of the market and the gradual maturity of the process, direct offset printing is based on the superior quality of its own four-color printing, coupled with the development of modern offset printing technology of the manufacturer in this field, direct offset printing of fine corrugated cardboard shows a good market expectation.

Offset printing can enter the field of direct color printing on micro-corrugated board, benefiting from the following two aspects: First, the successful development of new micro-corrugated cardboard has made important contributions to the realization of direct offset printing on micro-corrugated cardboard. Secondly, offset printing meets the need for the development of color printing on fine corrugated paperboard, while fine corrugated cardboard is also suitable for direct printing on offset printing presses, in which G-type and F-type micro-corrugated cardboard have good stability and can also be printed in the field. In particular, offset presses are now equipped with offset printing units and are no longer used for printing. This is also more conducive to the development of direct offset printing on fine corrugated board.

Second, the advantages of micro-corrugated paper directly offset printing

With the development of direct-printing micro-corrugated board technology with offset printing, it will replace flexo printing in certain areas of corrugated box printing. Figure 1 is a comparison of the quality and cost distribution of offset corrugated printing with direct offset printing of micro-corrugated cardboard with flexo and offset printing. As can be seen from Figure 1, direct offset printing is better than flexo printing and the cost is lower. In terms of quality and cost, direct offset printing is between flexo printing and offset printing between two processing methods.

Relative to the traditional color flexo printing process, direct offset printing has obvious advantages

â–  Excellent print quality, prints fine text and lines.

â–  Low printing cost, offset printing using conventional PS plates, low cost, and high standardization of offsets helps reduce production costs.

â–  Various special promotional information can improve printability.

â–  Short setup and adjustment time, more economical for short version.

Compared with the processing method of offsetting with cotton paper and corrugated paper, the advantages of direct printing of fine corrugated cardboard are:

â–  Eliminating the cost of counterfeiting, the reduction in the number of processes leads to a corresponding reduction in material waste.

â–  The amount of paper is small.

â–  Because there is no need for additional work process, the entire printing process time is relatively shortened, and the efficiency and resolution of the direct offset printing of fine corrugated cardboard are improved.

The first thing that should be considered in the direct offset printing of micro-corrugated cardboard is the uneven surface of micro-corrugated cardboard. Unlike the printing of plain paperboard, the printing of fine corrugated cardboard must take place on uneven surfaces caused by corrugations and troughs. Offset printing on uneven substrates is difficult to perform, and printing quality is difficult to guarantee.

Substrate irregularities are a major challenge for fine corrugated board printing. The structure that the printer must handle the grooves and backs corresponds to the three-dimensional plate structure. Another difficulty lies in the fact that in fact the pressure required for the transfer of ink from the blanket to the corrugated paper is a certain contact pressure in order to achieve a clear image in the grooved portion. This pressure is higher than the effective printing pressure on the smooth surface of the ridge, and it does not weaken the structure and stability of the fine corrugated cardboard. This condition is the starting point for direct offset printing on fine corrugated cardboard. Many corrugated paper suppliers already provide the necessary material quality to accommodate non-stop printing.

The blankets needed for direct offset printing on micro-corrugated cardboard should be quite flexible. It enables the printing process to use the highest printing pressure without causing too much pressure on the spine. This avoids excessive compression of the groove. In order to maintain the color of the fine corrugated cardboard and the stability of the box type. Due to the optimization of the blanket, the ink can be well transferred to the highest quality of fine corrugated board printing (to be continued)