Corrugated board printing and post-processing technology

Whether using a single combination machine or a more advanced combination unit, corrugated board into different specifications of corrugated boxes, nothing more than printing, pressure lines, slotting, cut corners and joints. It can also be printed, die-cut and joined.

Before the formation of corrugated board, a single combination machine had already printed the good side directly on the corrugated paper through the glue daffodil. Therefore, it only needs to complete the forming process of the corrugated box through the slitting machine, the crimping machine, the angle cutter, and the nail box machine. Since the 1980s, in order to ensure the overall quality of corrugated boxes, to increase production efficiency and reduce consumption in the stand-alone production process, integrated units such as integrated slitting, pressing lines, slotting and angle cutting have been used. Seven). Phase-cut production lines such as slitting, pressing lines and angle cutting were gradually phased out.

The single-faced corrugated board made by a single-faced machine must also be produced through a single unit and combined production before the molding process can be completed. However, unlike a single combination machine, the corrugated board that is produced by a single-sided mechanism and recovered by a single assembly machine can be printed on corrugated paper or corrugated board printing slot machines, corrugated board printing and die cutting machines, etc. Complete the molding process before the nail box or the complete connection.

The equipment that completes the molding process for the automatic corrugated board production line is only the large-scale printing slotting unit or the printing die-cutting unit.

A brief description of these two types of equipment is given below:

First, printing slotting unit

The equipment consists of feeding, printing (once, twice or more), grooving, indentation, cut corners, slitting, evacuation and stacking. Its device structure is illustrated (see Figure 18).

The structure of the printing slotting unit is described one by one.

1, feeding part

This part consists of jaws, feed rollers, vacuum adsorption and other parts. Mainly flat and accurate corrugated board is sent to the printing system.

2, printing part

This part is composed of an aniline ink circulation system, an inking rubber roller, an inker roller, a plate roller, and a gap adjuster for each part. The working status of the lash adjuster is accomplished by pneumatic components, electrical components and mechanical actions, respectively.

At present, the printing equipment used by the corrugated box manufacturers is different in the structure of the equipment due to the different nature of the ink used. A corrugated board printing machine using inkless printing can not only print corrugated board but also print general board. Its ink system is more complex than a flexographic printer. Millions of printed characters are close to the offset press. The use of aniline ink printing equipment is characterized by the use of a small viscosity of aniline ink, so the printer ink delivery structure is very simple.

The use of aniline ink to print corrugated cardboard makes it easy to deliver ink to the surface of the corrugated board. Not only is the breakage rate low, the quality of the printed design is very high. With this type of printing equipment, since the evaporation of moisture during the high-speed printing process causes a change in the concentration of aniline ink, the Universe adjusts the hue of printing by constantly adjusting the viscosity of the ink.

The printing plate used in the printing slotting machine mainly includes a rubber plate and a resin plate. Because the rubber plate is artificially engraved, it can only be used as an ordinary printing plate. The fine pattern text is printed using a resin plate.

3, pressure line, slotting, cutting angle, cut part

This part is mainly composed of upper and lower roller wheels, upper and lower slotted knives, upper and lower corner cutters, and slitting knives. The upper and lower roller wheels mainly complete the vertical pressure line of the corrugated board. The upper and lower slitting blades cut the lower concave knife to complete the opening of the corrugated cardboard; the upper and lower corner cutting blades pass through the upper corner cutting blades and the lower ones. The knife pad completes the formation of the tongue at the joint of the corrugated cardboard box, and is trimmed and trimmed according to the specified size.

In the printing and printing of the multicolor printing unit, and between the press line and the slot, the surface is provided with a netted pattern and the lower wheel is used as a transmission device, so that the corrugated cardboard is synchronously and accurately passed through each process.

4, waste and accumulation part

The main function of this section is to reverse slot, cut corners, and cut down the paper scraps through the pipe to collect and crush, and maintain the working environment of the site. The stacking section picks up the printed corrugated board, which is printed and then processed by the up-down adjustable conveying platform to accumulate the corrugated board for printing and grooving on the rack, and enters the next process.

5, nail box combination

The bonding part is mainly two methods of nailing and bonding. In addition to the traditional single nail box machine to complete the combination of corrugated box molding, in recent years, China has developed automatic, semi-automatic nail box machine. The structure of the head of the nail box device head arranged according to the box nails is divided into single oblique nails, double oblique nails, single straight nails, double straight nails, single horizontal nails and double horizontal nails. The current use of double oblique nails is more common, because of its arrangement structure enhances the binding strength of corrugated boxes. The box nail used for the nail box is a low-carbon steel flat tape with a coating. Specifications are divided into 16#, 18#, and 20#. 20# box nail flat yarn is used for the combination of corrugated cardboard.

Corrugated cartons and corrugated paper used in many merchandises must be packaged together because they are packaged directly in the process of merchandising. Some of the commodity packaging also requires the use of adhesive and bonding because of the requirements of its internal products. In recent years, China has successively developed and produced a semi-automatic or fully-automatic adhesive box machine (Figure 19). Paste combined with the use of sticky agent is mostly polyvinyl acetate emulsion, polyvinyl chloride solution, animal glue and starch adhesive.

Automatic sticking machine is a hi-tech product developed by China. It is mainly composed of paper feeding system, gluing system, folding forming correction system, counting accumulation and output system. Integrate light, electricity, gas as one of the high-precision timing control. High efficiency and high degree of automation ensure a high quality combination of corrugated boxes.

Excerpt from - Jiagong Machine Grid